Artículos Ciencias de la Salud

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Degeneracy in the neurological model of auditory speech repetition
(2023) Sajid, Noor; Gajardo-Vidal, Andrea; Ekert, Justyna O.; Lorca-Puls, Diego L.; Hope , Thomas M. H.; Green, David W.; Friston, Karl J.; Price, Cathy J.
Both classic and contemporary models of auditory word repetition involve at least four left hemisphere regions: primary auditory cortex for processing sounds; pSTS (within Wernicke’s area) for processing auditory images of speech; pOp (within Broca’s area) for processing motor images of speech; and primary motor cortex for overt speech articulation. Previous functional-MRI (fMRI) studies confirm that auditory repetition activates these regions, in addition to many others. Crucially, however, contemporary models do not specify how regions interact and drive each other during auditory repetition. Here, we used dynamic causal modelling, to test the functional interplay among the four core brain regions during single auditory word and pseudoword repetition. Our analysis is grounded in the principle of degeneracy—i.e., many-to-one structure-function relationships—where multiple neural pathways can execute the same function. Contrary to expectation, we found that, for both word and pseudoword repetition, (i) the effective connectivity between pSTS and pOp was predominantly bidirectional and inhibitory; (ii) activity in the motor cortex could be driven by either pSTS or pOp; and (iii) the latter varied both within and between individuals. These results suggest that different neural pathways can support auditory speech repetition. This degeneracy may explain resilience to functional loss after brain damage.
Network anatomy in logopenic variant of primary progressive aphasia
(2022) Mandelli, Maria Luisa; Lorca-Puls, Diego L.; Lukic, Sladjana; Montembeault, Maxime; Gajardo-Vidal, Andrea; Licata, Abigail; Scheffler, Aaron; Battistella, Giovanni; Grasso, Stephanie M.; Bogley, Rian; Ratnasiri, Buddhika M.; Joie, Renaud La; Mundada, Nidhi S.; Europa, Eduardo; Rabinovici, Gil; Miller, Bruce L.; Leon , Jessica De; Henry, Maya L.; Miller, Zachary; Gorno-Tempini, Maria Luisa
The logopenic variant of primary progressive aphasia (lvPPA) is a neurodegenerative syndrome characterized linguistically by gradual loss of repetition and naming skills resulting from left posterior temporal and inferior parietal atrophy. Here, we sought to identify which specific cortical loci are initially targeted by the disease (epicenters) and investigate whether atrophy spreads through predetermined networks. First, we used cross-sectional structural MRI data from individuals with lvPPA to define putative disease epicenters using a surface-based approach paired with an anatomically fine-grained parcellation of the cortical surface (i.e., HCP-MMP1.0 atlas). Second, we combined cross-sectional functional MRI data from healthy controls and longitudinal structural MRI data from individuals with lvPPA to derive the epicenter-seeded resting-state networks most relevant to lvPPA symptomatology and ascertain whether functional connectivity in these networks predicts longitudinal atrophy spread in lvPPA. Our results show that two partially distinct brain networks anchored to the left anterior angular and posterior superior temporal gyri epicenters were preferentially associated with sentence repetition and naming skills in lvPPA. Critically, the strength of connectivity within these two networks in the neurologically-intact brain significantly predicted longitudinal atrophy progression in lvPPA. Taken together, our findings indicate that atrophy progression in lvPPA, starting from inferior parietal and temporoparietal junction regions, predominantly follows at least two partially nonoverlapping pathways, which may influence the heterogeneity in clinical presentation and prognosis.
Enhanced left superior parietal activation during successful speech production in patients with left dorsal striatal damage and error-prone neurotypical participants
(2023) Geva, Sharon; Schneider, Letitia M.; Khan, Shamima; Lorca-Puls, Diego L.; gajardo vidal; Gajardo-Vidal, Andrea; PLORAS team; Hope, Thomas M. H.; Green, David W.; Price, Cathy J.
Functional imaging studies of neurotypical adults report activation in the left putamen during speech production. The current study asked how stroke survivors with left putamen damage are able to produce correct spoken responses during a range of speech production tasks. Using functional magnetic resonance imaging, activation during correct speech production responses was assessed in 5 stroke patients with circumscribed left dorsal striatal lesions, 66 stroke patient controls who did not have focal left dorsal striatal lesions, and 54 neurotypical adults. As a group, patients with left dorsal striatal damage (our patients of interest) showed higher activation than neurotypical controls in the left superior parietal cortex during successful speech production. This effect was not specific to patients with left dorsal striatal lesions as we observed enhanced activation in the same region in some patient controls and also in more error-prone neurotypical participants. Our results strongly suggest that enhanced left superior parietal activation supports speech production in diverse challenging circumstances, including those caused by stroke damage. They add to a growing body of literature indicating how upregulation within undamaged parts of the neural systems already recruited by neurotypical adults contributes to recovery after stroke.
The effect of right temporal lobe gliomas on left and right hemisphere neural processing during speech perception and production tasks
(2022) Yamamoto, Adam Kenji; Gajardo-Vidal, Andrea; Sanjuán, Ana; Pope, Rebecca; Parker Jones, Oiwi; Hope, Thomas M. H.; Prejawa, Susan; Oberhuber, Marion; Mancini, Laura; Ekert, Justyna O.; Creasey, Megan; Yousry , Tarek A.; Green, David W.; Price, Cathy J.
Using fMRI, we investigated how right temporal lobe gliomas affecting the posterior superior temporal sulcus alter neural processing observed during speech perception and production tasks. Behavioural language testing showed that three pre-operative neurosurgical patients with grade 2, grade 3 or grade 4 tumours had the same pattern of mild language impairment in the domains of object naming and written word comprehension. When matching heard words for semantic relatedness (a speech perception task), these patients showed under-activation in the tumour infiltrated right superior temporal lobe compared to 61 neurotypical participants and 16 patients with tumours that preserved the right postero-superior temporal lobe, with enhanced activation within the (tumour-free) contralateral left superior temporal lobe. In contrast, when correctly naming objects (a speech production task), the patients with right postero-superior temporal lobe tumours showed higher activation than both control groups in the same right postero-superior temporal lobe region that was under-activated during auditory semantic matching. The task dependent pattern of under-activation during the auditory speech task and over-activation during object naming was also observed in eight stroke patients with right hemisphere infarcts that affected the right postero-superior temporal lobe compared to eight stroke patients with right hemisphere infarcts that spared it. These task-specific and site-specific cross-pathology effects highlight the importance of the right temporal lobe for language processing and motivate further study of how right temporal lobe tumours affect language performance and neural reorganisation. These findings may have important implications for surgical management of these patients, as knowledge of the regions showing functional reorganisation may help to avoid their inadvertent damage during neurosurgery.
Factores pronósticos que influyen en los resultados de tratamiento de la periimplantitis: Una revisión sistemática
(2023) Sánchez, Camila; Asenjo, Claudia; Jofré, Jorge
Objetivo: Esta revisión sistemática tiene como objetivo identificar los factores pronósticos y/o determinantes del éxito del tratamiento de la periimplantitis. Materiales y métodos: Se realizó una búsqueda bibliográfica estructurada y exhaustiva para identificar referencias relevantes en las bases de datos MEDLINE (PubMed), Scielo y Springerlik. La estrategia de búsqueda se realizó combinando los términos periimplantitis con factores pronósticos y / o determinantes del éxito del tratamiento como MeSH y texto libre combinando con los operadores booleanos AND y OR. Se utilizó la clasificación de SIGN (Scottish Intercollegiate Guidelines Network) para analizar el nivel de evidencia. Resultados: De los 239 artículos revisados, 17 cumplieron con los criterios de selección para el análisis cualitativo de la evidencia. Conclusiones: El tipo de implante (macro y microgeometría) y la morfología del defecto, los cuales dificulta el acceso a las superficies contaminadas, son factores que influyen en el resultado del tratamiento de la periimplantitis. No hay evidencia sobre el método de descontaminación más eficaz. Las condiciones generales como la diabetes mellitus y la presencia de enfermedad periodontal activa afectan el resultado del tratamiento, así como la frecuencia de un programa de mantención de higiene profesional postquirúrgica, la cual mejora la sobrevida del implante. Objective: This systematic review aimed at identifying prognostic factors influencing periimplantitis treatment outcomes. Materials and methods: A structured and comprehensive literature search was performed to identify relevant references from MEDLINE (PubMed), Scielo and Springerlik databases. The search strategy was carried out combining the search terms periimplantitis with prognostic factors and/or determinants of treatment success as MeSH and free text combining with the boolean logical operators AND and OR. The SIGN (Scottish Intercollegiate Guidelines Network) was used to analyze the level of evidence. Results: From 239 articles reviewed, 18 fulfilled the selection criteria for the qualitative analysis of the evidence. Conclusions: The type of implant (macro and microgeometry) and the defect morphology, which make access to contaminated surfaces difficult, are factors that influence the outcome of peri-implantitis treatment. There is no evidence on the most effective decontamination method. General conditions such as diabetes mellitus and the presence of active periodontal disease affect the outcome of the treatment. as Also, the frequency of a post-surgical professional hygiene maintenance program improves the dental implant survival post-treatment
Mental training in dentistry: A scoping review
(2023) Jofré, Jorge; Michel, Manuel; Quintana, Paula; Fuentes, Jeannette; Conrady, Yuri; Valenzuela, Daniela; Asenjo, Claudia
Introduction: Clinical motor skills are essential to train dental students. There is evidence that imagery serves to acquire and improve motor skills, but there is scarce information on its application in dental education. In order to broadly map the available evidence and to detect knowledge gaps in the mental training used to develop motor skills in dentistry, a scoping review was conducted. Materials and methods: A structured search was conducted to identify relevant references from the Web of Science, Scopus and MEDLINE/PubMed databases for studies addressing mental training methods applied to develop motor skills in dentistry. Results: A total of 758 articles were screened and four were selected, all of which were randomized clinical trials. Three studies investigated the effectiveness of visual imagery, and one investigated kinesthetic imagery. The research theme identified was motor skill acquisition. Conclusion: The reviewed studies indicate the usefulness of mental training for skill acquisition in dentistry. To improve the generalizability of the results, further research with standardized mental training on motor skills in dentistry is needed.
Remodelación de papila gingival interdental con ácido hialurónico. Una solución estética.
(2019) Iribarra-Leigh, Javiera; Soto-Royo, María; Rubio-Muñoz, María; Torres-Castillo, Oscar; Baldeig, Loreta; Gómez-Morales, Andrés
El objetivo de este trabajo es evaluar el efecto de remodelación y relleno mediante aplicación de ácido hialurónico en papilas gingivales de sector estético con defectos de triángulo negro en un paciente tratado periodontalmente. Se inyectaron 0.15 ml de gel de ácido hialurónico dividido en 3 sesiones. Clínicamente se observó aumento de volumen y aumento de dimensiones verticales y horizontales en las papilas, mejorando así los parámetros estéticos. Como conclusión la aplicación de ácido hialurónico es efectiva en la remodelación y relleno en pérdidas de papila clase I de Nordland y Tarnow.
Generalizing post-stroke prognoses from research data to clinical data
(2019) Loughnan, Robert; Lorca, Diego; Gajardo, Andrea; Espejo, Valeria; Gillebert, Céline; Mantini, Dante; Price, Cathy; Hope, Thomas
Around a third of stroke survivors suffer from acquired language disorders (aphasia), but current medicine cannot predict whether or when they might recover. Prognostic research in this area increasingly draws on datasets associating structural brain imaging data with outcome scores for ever-larger samples of stroke patients. The aim is to learn brain-behaviour trends from these data, and generalize those trends to predict outcomes for new patients. The practical significance of this work depends on the expected breadth of that generalization. Here, we show that these models can generalize across countries and native languages (from British patients tested in English to Chilean patients tested in Spanish), across neuroimaging technology (from MRI to CT), and from scans collected months or years after stroke for research purposes, to scans collected days or weeks after stroke for clinical purposes. Our results suggest one important confound, in attempting to generalize from research data to clinical data, is the delay between scan acquisition and language assessment. This delay is typically small for research data, where scans and assessments are often acquired contemporaneously. But the most natural, clinical application of these predictions will employ acute prognostic factors to predict much longer-term outcomes. We mitigated this confound by projecting the clinical patients' lesions from the time when their scans were acquired, to the time when their language abilities were assessed; with this projection in place, there was strong evidence that prognoses derived from research data generalized equally well to research and clinical data. These results encourage attention to the confounding role that lesion growth may play in other types of lesion-symptom analysis.
Autohemotherapy with ozone as a possible effective treatment for Fibromyalgia
(2019) Moreno, Ana; Macías, Laura; Valverde, Rocío; Ortiz, Tamara; Fernández, Ana; Moliní, Angel; De Miguel, Manuel
Objective: The objective of this study is to evaluate the effectiveness of autohemotherapy with ozone in the management of fibromyalgia (FM). Design: 20 FM patients (according to the criteria of the American College of Rheumatology), were treated with 10 sessions of ozone hemotherapy (2 sessions per week) with a concentration of 30-60 mcgr/ml. The health condition of the patients was evaluated before and after treatment, through the Fibromyalgia Impact Questionnaire (FIQ). Blood samples were obtained from all patients by venous puncture for biochemical routine analysis and serotonin levels in serum and the following peripheral blood mononuclear cells (BMCs) were isolated for oxidative stress quantification: reactive oxygen species (ROS) generation, and lipid peroxidation (LP) and protein carbonyl (PC) content, as these are signs of oxidative cell damage. Results: All patients treated with ozone reported an improvement in sleep and mental alertness, a marked decrease of asthenia accompanied by a decrease of FIQ as well as tender points, and a moderate increase of serotonin levels. Also, an important decrease of LP and PC was observed; ROS also decreased, although less obvious, which indicates a reduction in oxidative stress levels. Conclusions: The autohemotherapy with ozone in patients with FM showed an important decline of tender points and FIQ score, as well as a decrease of oxidative stress levels. This treatment allows patients to face life with greater vitality and less drug use, diminishing harmful side effects. Further investigation should be carried out, including groups with more patients and clinical trials, to elucidate the effect of ozone therapy in patients suffering from FM.
Sistemas Híbridos de Saúde: uma análise comparada internacional de políticas de proteção e equidade: Chile
(2019) Oliva, Patricio; Narváez, Carmen
Este livro é produto da pesquisa ‘Análise Comparada de Políticas e Sistemas Nacionais de Saúde: problemas, agendas e políticas, no âmbito do Projeto QGEP – Qualiﬁcação da Gestão Estratégica e Participativa do Sistema Único de Saúde (SUS)’. Reúne, além desta Introdução, dez capítulos de estudos de caso de países latino-americanos e europeus e um capítulo no qual se analisa os casos internacionais comparativamente à luz da experiência brasileira. Os estudos dos países – executados por meio de cooperação entre pesquisadores do Departamento de Ciências Sociais da Escola Nacional de Saúde Pública Sergio Arouca da Fundação Oswaldo Cruz (DCS/ Ensp/Fiocruz) e a Secretaria de Gestão Estratégica e Participativa do SUS e do Ministério da Saúde (SGEP/MS) – envolveram a parceria com pesquisadores da Argentina, do Chile, do Uruguai, da Colômbia, da França, da Inglaterra, da Irlanda, da Escócia e de Portugal. A ideia de fazer um estudo comparado em perspectiva internacional teve como ponto de partida algumas questões que, no sistema de saúde brasileiro, apareciam como problemas decorrentes de seus limites institucionais e políticos para fazer frente aos problemas de saúde com equidade. A ideia central do projeto consistia em produzir, com o apoio de evidências e análise, uma compreensão maior dos processos que, nos países selecionados, produziam certas conﬁgurações e resultados dos sistemas de saúde e, com isso, propor uma agenda de reformas visando efetivar um sistema universal de qualidade e resolutivo. Comparar sistemas e políticas de saúde signiﬁcou, em termos de fundamentos teóricos, reconhecer o caráter singular de cada país e das suas trajetórias históricas e identiﬁcar os elementos de comparação por meio das agendas políticas (nas quais se expressam os problemas), das soluções (pelas quais se depreendem as respostas políticas e os aprendizados institucionais) e do modo de organização dos mecanismos de governança desses sistemas. Na perspectiva dos valores e da normatividade que regem os sistemas de saúde, a pesquisa partiu da premissa de que as sociedades democráticas implicam instituições que viabilizem a participação política dos cidadãos e garantam a proteção dos direitos de minorias e de grupos vulneráveis. As análises das estruturas e processos conformando os sistemas nacionais de saúde abordam, com base nas trajetórias nacionais, certas convergências, mas também as escolhas singulares no enfrentamento das vulnerabilidades sociais. Os sistemas de saúde em países industrializados, particularmente nos casos em que os sistemas políticos são abertos, competitivos e dotados de elevado ativismo societário, possuem características dinâmicas e adaptativas. A mudança é constante, porém delimitada pelas suas conﬁgurações essenciais em termos de titularidade de direitos, mecanismos de ﬁnanciamento e estruturas de governança. Os principais mecanismos de mudança, usualmente de caráter incrementalista, ocorrem por meio de agendas políticas e da forma como interagem com os padrões institucionais pelos quais ﬂuem as políticas. Um foco privilegiado trata das funções do setor público e da capacidade de governo em promover proteção social no âmbito das políticas de saúde, especialmente em termos de redução das desigualdades sociais, desenvolvimento de políticas de equidade, fortalecimento da capacidade política de indivíduos e grupos sociais. As respostas dos países a problemas e crises fazem parte do repertório das alternativas que se colocam nos diversos contextos e trajetórias nacionais. Considerando a crise setorial do Brasil acirrada também pelas condições políticas após 2015, este estudo considerou as oportunidades de produzir conhecimento, informação, evidência, subsídio, reﬂexão e propostas reformadoras orientadas a efetivar a saúde como direito do cidadão. Os espaços acadêmicos, institucionais e políticos que a pesquisa deve ocupar, portanto, são os de uma pesquisa que pretende ser efetivamente relevante, marco referencial para o diálogo e o debate entre os atores políticos interessados em uma agenda progressista e de justiça social. O mesmo roteiro para o desenvolvimento dos estudos de caso foi seguido, para que se pudesse acompanhar como problemas similares são enfrentados em distintos contextos nacionais. Os casos utilizaram fontes primárias e secundárias; e o projeto procurou se alinhar ao estado da arte de análise de políticas, agendas e processos decisórios de acordo com a literatura especializada. Como parte da metodologia que orientou os estudos, um modelo de análise inspirado na tradição de análise institucional foi desenhado segundo as necessidades que se colocavam para o projeto. A partir de problemas identiﬁcados para o sistema brasileiro, um conjunto de aspectos relativos à agenda política setorial, a soluções e a respostas políticas foi abordado em cada uma das experiências nacionais selecionadas. Além da conﬁguração dos mecanismos de governança, envolvendo a gestão local, regional e participativa, também tomamos como objeto de análise outros problemas enfrentados pelos sistemas de saúde. Expressando-se por meio de agendas políticas, as soluções propostas a esses problemas traduzem as respostas políticas e os aprendizados institucionais, além dos mecanismos vigentes de governança desses sistemas. A pesquisa envolveu duas questões teóricas centrais. A primeira se refere aos processos adaptativos que os sistemas nacionais de saúde apresentam ante as mudanças de caráter social, econômico, demográﬁco e de inovação tecnológica observadas e sua manifestação na forma de agendas políticas. A outra questão trata da formulação de um modelo de comparação de processos políticos entre países de naturezas distintas. Como o estudo comparado foi concebido a partir da experiência brasileira, em que o sistema de saúde, a partir da Constituição Cidadã de 1988, incorporou a participação pública e políticas especíﬁcas para grupos vulneráveis, como indígenas, quilombolas, discriminados por gênero (mulheres, LGBTQIA+) e portadores de patologias negligenciadas, achamos importante abordar esses temas, também nos outros países. Procuramos entender a conﬁguração da participação pública nos sistemas de saúde analisados e o signiﬁcado das políticas de equidade que, nos diferentes países, articulam-se às políticas que, de modo geral, orientam-se à redução das desigualdades sociais. Aqui, encontramos diferenças marcantes no próprio signiﬁcado de vulnerabilidade para as políticas de saúde, entre contextos latino-americano e europeu. Identiﬁcamos, de certa forma, avanços substantivos nos países latino-americanos, nos quais a capacidade política dos grupos vulneráveis impulsionando a agenda dos direitos à diferença foi incorporada pelos sistemas e políticas do setor saúde, e não apenas pelo sistema jurídico. Nos países europeus e de universalismo consolidado no pós-guerra, minorias e grupos identitários não têm sido objeto de políticas de saúde especíﬁcas, como se deu nas duas primeiras décadas deste século nos países latino-americanos abordados. Nesses países, embora muito mais fragmentados e desiguais, a atuação dos movimentos sociais e as conquistas democráticas foram decisivas para que as políticas de saúde incorporassem uma deﬁnição de vulnerabilidade que também incluísse as diferenças identitárias. Da mesma forma, a gestão participativa da política de saúde envolve a institucionalização de mecanismos que, na América Latina, canalizam a participação pública (como os conselhos de saúde) e fortalecem a atuação dos grupos e das coalizões de defesa dos grupos que, apesar de numerosos, são política e socialmente vulneráveis. As formas de articulação entre vulnerabilidades sociais que demandam proteção especíﬁca e necessidades em saúde que demandam proteção de caráter universal, típicas dos sistemas públicos de caráter redistributivo, assumem, em cada contexto nacional, distintas formas e traduções institucionais. No primeiro capítulo, a partir de teorias do campo, discutimos as diﬁculdades e os limites de comparar situações, trajetórias e contextos históricos que sempre são singulares. Ainda que os sistemas de saúde possam ser classiﬁcados por meio de tipologias, e este foi o procedimento clássico dos primeiros estudos comparados, as tipologias são modelos – tipos ideais – que apreendem certas conﬁgurações em um determinado momento do tempo. No entanto, são limitadas para capturar os processos de mudança dinâmicos produzidos como respostas incrementais e adaptativas vinculadas a contextos especíﬁcos. É possível, contudo, comparar como vários problemas comuns aos sistemas de saúde em diferentes países se traduzem em agendas e políticas deﬁnidas para enfrentá-los. Essa foi a proposta desenvolvida nos dez capítulos apresentando os estudos de caso, estruturados com base em um roteiro comum deﬁnido para permitir alguma comparação entre os países. Além das características básicas do contexto político e institucional e do sistema de saúde de cada país, o roteiro incluiu a abordagem dos seguintes tópicos: políticas de descentralização, de ﬁnanciamento, de participação social e de equidade. A obtenção de consenso entre pesquisadores de nove instituições internacionais para que elaborassem a pesquisa com base em um roteiro comum predeﬁnido pelos coordenadores do projeto para o desenvolvimento dos estudos foi resultado de uma metodologia de trabalho. Uma proposta preliminar foi enviada para os pesquisadores convidados, os quais, após o aceite de participação, ﬁcaram responsáveis pelo estudo e, a seu critério, pela organização de uma equipe. Após uma primeira versão de cada estudo, foram realizadas oﬁcinas – a maior parte no Brasil – especíﬁcas para cada país, com cada uma das equipes ou parte delas, para discutir avanços e lacunas, sempre tendo em vista as possibilidades de comparação e a compreensão das convergências e particularidades de cada caso. O roteiro comum seguido nos estudos de caso, entretanto, não foi tomado pelos coordenadores do projeto nem pelos pesquisadores dos países selecionados como uma camisa de força constrangendo o desenvolvimento dos estudos segundo uma visão própria dos autores sobre os processos e atores mais relevantes nos cenários nacionais. Se, por um lado, todos os estudos deveriam abordar certas questões previamente deﬁnidas como comuns aos sistemas de saúde; por outro, o caráter singular e as abordagens especíﬁcas dos textos implicaram diversidade de ênfases e análises nos estudos. Algumas questões foram colocadas em relevo por um estudo, mas não por outros, o que não impediu, mas delimitou o escopo da análise comparada. Colocamos isso como uma espécie de aviso aos leitores, ressaltando, ao mesmo tempo, o desaﬁo que consistiu este projeto, com uma abordagem histórica e qualitativa de processos e políticas, o que já estabelece, desde o início, o problema da ‘comparação entre diferentes’. O que se procurou foi iluminar e analisar convergências e singularidades, focalizando justamente entender como os ‘diferentes’ tratam os mesmos problemas por meio de políticas. Estas questões são discutidas no último capítulo: como países tão heterogêneos, com trajetórias históricas e conﬁgurações institucionais tão especíﬁcas, ao lidar com problemas similares na saúde, constroem suas respostas, reformas e inovações, sob os impactos da ação de atores e coalizões políticas? Os sistemas de saúde foram adaptando seus componentes e seu modo de organização e governança às mudanças às condições sociais, econômicas, políticas e epidemiológicas, incrementalmente, sem metamorfoses radicais, produzindo conﬁgurações híbridas. Além dessas considerações sobre os estudos de caso, da perspectiva comparada adotada, das conﬁgurações institucionais e dos eixos de políticas tratados neste livro, cabe efetuar algumas considerações signiﬁcativas sobre importantes eventos de repercussão global ocorridos desde a ﬁnalização da pesquisa. Nos países incluídos na pesquisa deste livro, esses eventos afetam o modo como as políticas públicas, enquanto um terreno de disputas e de mudanças institucionais, adaptam-se a mudanças de contextos históricos. Estamos nos referindo, principalmente, às massivas manifestações sociais no Chile, aos resultados das eleições gerais no Brasil em 2018 e à recente pandemia de Covid-19. Esses eventos afetam diretamente elementos tratados em perspectiva comparada nesta pesquisa – conﬁgurações dos sistemas de saúde, padrões de descentralização, políticas de equidade e participação social. No caso do Chile – e, apesar das diferenças de agenda política, também como emulação dos eventos em Hong Kong –, as manifestações massivas, de início coordenadas e, em seguida, expandidas para uma ampla pauta de mudanças na conﬁguração do próprio aparelho de Estado, deram as feições do protagonismo de conﬂitos extrainstitucionais no País. Tais manifestações, em dimensões e diversidade, são inéditas na América do Sul. Elas trouxeram para a pauta política todos os itens de política pública de proteção social represadas no Chile desde a sua redemocratização. A forma descentralizada de organização de atos públicos e de adoção de temas afetou o modo como coalizões progressistas e voltadas a mudanças sociais redistributivas atuam ou como foram atravessadas por ações não coordenadas. Seu desfecho por meio de um consenso em torno de uma nova Constituição foi congelado pela emergência da pandemia de Covid-19. No Brasil, os resultados eleitorais do ﬁnal de 2018 explicitaram o conﬂito elevado observado entre os valores da coalizão política vencedora e os principais elementos ressaltados por este estudo comparativo. Essa coalizão expressou um ideário autoritário sempre latente no Brasil e de presença política visível também nos Estados Unidos e em importantes países europeus. Esses ideários reagem aos avanços sociais e políticos em prol de maior equidade e proteção social a minorias e grupos vulneráveis. Esse tipo de coalizão acessou o poder pela primeira vez no Brasil por via eleitoral. A agenda política do governo atual afeta a conﬁguração do sistema sanitário em função da perda de protagonismo do sistema público e de seu esvaziamento quanto ao ﬁnanciamento setorial e desmonte de estruturas de governança federativa horizontal e vertical. Em termos de descentralização política, há elementos de ruptura federativa com relação aos governadores e de conﬂito com os aspectos cooperativos, embora não dominantes, do federalismo no sistema público de saúde. Quanto à participação social, além do fechamento e/ou esvaziamento de organismos colegiados de governança do SUS, o apoio de camadas pobres da população e de diversas igrejas pentecostais enraizadas nessas comunidades afeta diretamente a dimensão consensuada dos conselhos de saúde e a atuação de movimentos sociais. Por ﬁm, a agenda observada nas políticas de equidade representa um dos principais alvos da nova coalizão de governo. Os elementos sociotrópicos relacionados com o combate à violência racial, de gênero e de proteção de vulneráveis são atacados em nome de um combate cultural que recupera traços medievais. A pauta de costumes, parte importante dos discursos da coalizão que alcança o poder, é expressa em narrativas como combate a ‘ideologia de gênero’, desmonte das estruturas do Ministério da Saúde que centralizavam a gestão das políticas de equidade para grupos vulneráveis e programas de formação que se adequem ao escopo do que se chama ‘escola sem partido’. Com relação à pandemia de Covid-19, os efeitos sobre os sistemas sanitários de todos os países estudados são devastadores. A capacidade nacional de vigilância sanitária, de proteção de vulneráveis e de oferta e acesso a serviços emergenciais de saúde foi a tônica nos países ocidentais. Temas tradicionais da atenção à saúde são afetados enquanto projetos de mudança. A atenção primária passa a dividir com os investimentos elevados em capacidade hospitalar. Os componentes de vigilância sanitária envolvidos com a atenção primária devem mudar de conﬁguração com o retorno de práticas de rastreamento e controle de indivíduos e famílias pelo Estado nacional. A estratégia industrial dos países para o setor saúde, fundada na exportação de plantas industriais para países com mecanismos limitados de proteção social e ao trabalho, deverá ser adaptada para modelos tradicionais de incentivos de políticas de desenvolvimento local. O conﬂito em curso, em que um dos polos visa ao enfraquecimento de governanças globais, recebe novamente, como no ocorrido após as últimas guerras mundiais, o incentivo e o movimento na direção de proteção global mútua e cooperativa perante a vulnerabilidade que novas ameaças biológicas e ambientais estabelecem para a humanidade. Todos esses aspectos considerados, este projeto foi um desaﬁo e um aprendizado que esperamos que tenha continuidade. Em especial, a dimensão comparativa entre unidades e identidades muito diferenciadas merece a atenção que as fronteiras do conhecimento esperam e exigem de intelectuais, cientistas, dirigentes e lideranças políticas em favor de maior solidariedade e proteção nas nações e entre nações.
The Presence of Lingual Foramina and Canals on CBCT on Patients over 18 Years of Age
(2018) Sanhueza, Álvaro; Briner, Michelle; Calvo, Magdalena; Cisternas, Alejandra
Lingual foramina and canals are located in the midline of the jaw, which are important due to their neurovascular content. The location of the lingual foramina and canals can be classified according to their relationship to the mental spines; upper, middle or lower. The objective of the study was to determine the prevalence, size and anatomic location of the lingual foramina and canals and in patients older than 18 years of age that were patients at the Universidad de Los Andes, Dentistry Clinic, San Bernardo, Santiago, Chile. Furthermore, to establish sex differences regarding the presence, location and diameter of lingual foramina. From the sample total, 296 foramina were found, from which 133 (45 %) were upper foramina, 43 (15 %) middle foramina and 120 (40 %) lower foramina. In both sexes the prevalence of upper foramina was higher. Regarding the vertical diameter of the foramina, the median of the upper foramina was 0.76 mm, the median of the middle foramina was 0.52 mm and the median of the lower foramina was 0.55 mm. As for the length of the lingual canals, the middle canal was the largest (7.48 mm), followed by the upper (7.53 mm) and the lower (6.83 mm). There was no statistically significant difference between sexes regarding the amount and size of the lingual foramina, neither regarding the size and age of the patients, but there was a difference between the lengths of the canals, being the male patients the ones that presented longer canals in the 3 different kinds. Because of the high prevalence of foramina and canals in the sample, it is recommended to consider them in the planning of surgical procedures on the mandible midline.
Factorial structure and internal consistency of Clinic Teachers Assessment Questionnaire in Speech Therapy Internship
(2018) Martínez Cifuentes, Renato; Pérez Villalobos, Cristhian; León Valdés, Hernán; Carmona, Lorena
Introduction : Final year Speech Therapy students are supervised by a tutor in the clinic, who plays a role of teacher without necessarily being qualified. There are not instruments available to evaluate if these tutors teaching is proven to be reliable. Objective: The aim is to evaluate the psychometric properties of "Clinic Teachers Assessment Questionnaire (CTAQ)" in Speech Therapy degree internships in a traditional university in Concepción. Method : Analytical, relational and mixed studies, using surveys. The surveys were answered by 43 students who were selected using a sampling method that was not probabilistic in terms of accessibility. These students carried out 137 reviews using the CTAQ, evaluating 38 tutors. Informed consent was given and it was authorized by the person in charge of the major. Results : An exploratory factor analysis was carried out using the Kaiser-Meyer- Olkin=0,95 statistical calculation of sampling adequacy and Bartlett's test of sphericity c2(325)=4092,05; p<0,001. The Kaiser-Guttman criterion was used when estimating the number of factors, identifying three factors with eigenvalues of 16,71, 1,23 and 1,07. These factors displayed reliability with Cronbach's alpha coefficients a=0,97, a=0,93 and a=0,89. They also displayed a direct correlation with the teacher's overall score of that were statistically significant. Conclusions : The CTAQ shows signs of reliability and validity of design and criteria. The CTAQ displays the following factors: "promotes ongoing dialogue", "promotes conditions for safe performance" and "teaches techniques". The CTAQ allows the clinical teachers to be characterized, and enables teaching innovation in the internships.
Damage to Broca's area does not contribute to long-term speech production outcome after stroke
(2021) Gajardo-Vidal, Andrea; Lorca, Diego; Team, Ploras; Warner, Holly; Pshdary, Bawan; Crinion, Jennifer; Leff, Alexander; Hope, Thomas; Geva, Sharon; Seghier, Mohamed; Green, David; Bowman, Howard; Price, Cathy
Broca's area in the posterior half of the left inferior frontal gyrus has long been thought to be critical for speech production. The current view is that long-term speech production outcome in patients with Broca's area damage is best explained by the combination of damage to Broca's area and neighbouring regions including the underlying white matter, which was also damaged in Paul Broca's two historic cases. Here, we dissociate the effect of damage to Broca's area from the effect of damage to surrounding areas by studying long-term speech production outcome in 134 stroke survivors with relatively circumscribed left frontal lobe lesions that spared posterior speech production areas in lateral inferior parietal and superior temporal association cortices. Collectively, these patients had varying degrees of damage to one or more of nine atlas-based grey or white matter regions: Brodmann areas 44 and 45 (together known as Broca's area), ventral premotor cortex, primary motor cortex, insula, putamen, the anterior segment of the arcuate fasciculus, uncinate fasciculus and frontal aslant tract. Spoken picture description scores from the Comprehensive Aphasia Test were used as the outcome measure. Multiple regression analyses allowed us to tease apart the contribution of other variables influencing speech production abilities such as total lesion volume and time post-stroke. We found that, in our sample of patients with left frontal damage, long-term speech production impairments (lasting beyond 3 months post-stroke) were solely predicted by the degree of damage to white matter, directly above the insula, in the vicinity of the anterior part of the arcuate fasciculus, with no contribution from the degree of damage to Broca's area (as confirmed with Bayesian statistics). The effect of white matter damage cannot be explained by a disconnection of Broca's area, because speech production scores were worse after damage to the anterior arcuate fasciculus with relative sparing of Broca's area than after damage to Broca's area with relative sparing of the anterior arcuate fasciculus. Our findings provide evidence for three novel conclusions: (i) Broca's area damage does not contribute to long-term speech production outcome after left frontal lobe strokes; (ii) persistent speech production impairments after damage to the anterior arcuate fasciculus cannot be explained by a disconnection of Broca's area; and (iii) the prior association between persistent speech production impairments and Broca's area damage can be explained by co-occurring white matter damage, above the insula, in the vicinity of the anterior part of the arcuate fasciculus.
Brain regions that support accurate speech production after damage to Broca’s area
(2021) Lorca-Puls, Diego L.; Gajardo-Vidal, Andrea; PLORAS Team; Oborhuber, Marion; Prejawa, Susan; Hope, Thomas M.H.; Leff, Alexander P.; Green, David W.; Price, Cathy J.
Broca’s area in the posterior half of the left inferior frontal gyrus has traditionally been considered an important node in the speech production network. Nevertheless, recovery of speech production has been reported, to different degrees, within a few months of damage to Broca’s area. Importantly, contemporary evidence suggests that, within Broca’s area, its posterior part (i.e. pars opercularis) plays a more prominent role in speech production than its anterior part (i.e. pars triangularis). In this study, we therefore investigated the brain activation patterns that underlie accurate speech production following stroke damage to the opercular part of Broca’s area. By combining functional MRI and 13 tasks that place varying demands on speech production, brain activation was compared in (i) seven patients of interest with damage to the opercular part of Broca’s area; (ii) 55 neurologically intact controls; and (iii) 28 patient controls with left-hemisphere damage that spared Broca’s area. When producing accurate overt speech responses, the patients with damage to the left pars opercularis activated a substantial portion of the normal bilaterally distributed system. Within this system, there was a lesion-site-dependent effect in a specific part of the right cerebellar Crus I where activation was significantly higher in the patients with damage to the left pars opercularis compared to both neurologically intact and patient controls. In addition, activation in the right pars opercularis was significantly higher in the patients with damage to the left pars opercularis relative to neurologically intact controls but not patient controls (after adjusting for differences in lesion size). By further examining how right Crus I and right pars opercularis responded across a range of conditions in the neurologically intact controls, we suggest that these regions play distinct roles in domain-general cognitive control. Finally, we show that enhanced activation in the right pars opercularis cannot be explained by release from an inhibitory relationship with the left pars opercularis (i.e. dis-inhibition) because right pars opercularis activation was positively related to left pars opercularis activation in neurologically intact controls. Our findings motivate and guide future studies to investigate (i) how exactly right Crus I and right pars opercularis support accurate speech production after damage to the opercular part of Broca’s area and (ii) whether non-invasive neurostimulation to one or both of these regions boosts speech production recovery after damage to the opercular part of Broca’s area.
Right cerebral motor areas that support accurate speech production following damage to cerebellar speech areas
(2021) Geva, Sharon; Schneider, Letitia; Roberts, Sophie; Khan, Shamima; Gajardo-Vidal, Andrea; Lorca, Diego; PLORAS team; Hope, Thomas; Green, David; Price, Cathy
Specific regions of the cerebellum are activated when neurologically intact adults speak, and cerebellar damage can impair speech production early after stroke, but how the brain supports accurate speech production years after cerebellar damage remains unknown. We investigated this in patients with cerebellar lesions affecting regions that are normally recruited during speech production. Functional MRI activation in these patients, measured during various single word production tasks, was compared to that of neurologically intact controls, and patient controls with lesions that spared the cerebellar speech production regions. Our analyses revealed that, during a range of speech production tasks, patients with damage to cerebellar speech production regions had greater activation in the right dorsal premotor cortex (r-PMd) and right supplementary motor area (r-SMA) compared to neurologically intact controls. The loci of increased activation in cerebral motor speech areas motivate future studies to delineate the functional contributions of different parts of the speech production network, and test whether non-invasive stimulation to r-PMd and r-SMA facilitates speech recovery after cerebellar stroke.
Better long-term speech outcomes in stroke survivors who received early clinical speech and language therapy: What’s driving recovery?
(2021) Roberts, Sophie; Bruce, Rachel M.; Lim, Louise; Woodgate, Hayley; Ledingham, Kate; Anderson, Storm; Lorca-Puls, Diego L.; Gajardo-Vidal, Andrea; Leff, Alexander P.; Hope, Thomas M.H.; Green, David W.; Crinion, Jennifer T.; Price, Cathy J.
Establishing whether speech and language therapy after stroke has beneficial effects on speaking ability is challenging because of the need to control for multiple non-therapy factors known to influence recovery. We investigated how speaking ability at three time points post-stroke differed in patients who received varying amounts of clinical therapy in the first month post-stroke. In contrast to prior studies, we factored out variance from: initial severity of speaking impairment, amount of later therapy, and left and right hemisphere lesion size and site. We found that speaking ability at one month post-stroke was significantly better in patients who received early therapy (n = 79), versus those who did not (n = 64), and the number of hours of early therapy was positively related to recovery at one year post-stroke. We offer two non-mutually exclusive interpretations of these data: (1) patients may benefit from the early provision of self-management strategies; (2) therapy is more likely to be provided to patients who have a better chance of recovery (e.g., poor physical and/or mental health may impact suitability for therapy and chance of recovery). Both interpretations have implications for future studies aiming to predict individual patients’ speech outcomes after stroke, and their response to therapy.
Lesions that do or do not impair digit span: a study of 816 stroke survivors
(2021) Geva, Sharon; Truneh, Teodros; Seghier, Mohamed; Hope, Thomas; Crinion, Jennifer; Gajardo-Vidal, Andrea; Lorca, Diego; Green, David; PLORAS Team; Cathy J Price
Prior studies have reported inconsistency in the lesion sites associated with verbal short-term memory impairments. Here we asked: How many different lesion sites can account for selective impairments in verbal short-term memory that persist over time, and how consistently do these lesion sites impair verbal short-term memory? We assessed verbal short-term memory impairments using a forward digit span task from the Comprehensive Aphasia Test. First, we identified the incidence of digit span impairments in a sample of 816 stroke survivors (541 males/275 females; age at stroke onset 56 ± 13 years; time post-stroke 4.4 ± 5.2 years). Second, we studied the lesion sites in a subgroup of these patients (n = 39) with left hemisphere damage and selective digit span impairment-defined as impaired digit span with unimpaired spoken picture naming and spoken word comprehension (tests of speech production and speech perception, respectively). Third, we examined how often these lesion sites were observed in patients who either had no digit span impairments or digit span impairments that co-occurred with difficulties in speech perception and/or production tasks. Digit span impairments were observed in 222/816 patients. Almost all (199/222 = 90%) had left hemisphere damage to five small regions in basal ganglia and/or temporo-parietal areas. Even complete damage to one or more of these five regions was not consistently associated with persistent digit span impairment. However, when the same regions were spared, only 5% (23/455) presented with digit span impairments. These data suggest that verbal short-term memory impairments are most consistently associated with damage to left temporo-parietal and basal ganglia structures. Sparing of these regions very rarely results in persistently poor verbal short-term memory. These findings have clinical implications for predicting recovery of verbal short-term memory after stroke.
Dissociating the functions of three left posterior superior temporal regions that contribute to speech perception and production
(2021) Ekert, Justyna; Gajardo-Vidal, Andrea; Lorca, Diego; Hope, Thomas; Dick, Fred; Crinionc, Jennifer; Greend, David; Price, Cathy
Prior studies have shown that the left posterior superior temporal sulcus (pSTS) and left temporo-parietal junction (TPJ) both contribute to phonological short-term memory, speech perception and speech production. Here, by conducting a within-subjects multi-factorial fMRI study, we dissociate the response profiles of these regions and a third region - the anterior ascending terminal branch of the left superior temporal sulcus (atSTS), which lies dorsal to pSTS and ventral to TPJ. First, we show that each region was more activated by (i) 1-back matching on visually presented verbal stimuli (words or pseudowords) compared to 1-back matching on visually presented non-verbal stimuli (pictures of objects or non-objects), and (ii) overt speech production than 1-back matching, across 8 types of stimuli (visually presented words, pseudowords, objects and non-objects and aurally presented words, pseudowords, object sounds and meaningless hums). The response properties of the three regions dissociated within the auditory modality. In left TPJ, activation was higher for auditory stimuli that were non-verbal (sounds of objects or meaningless hums) compared to verbal (words and pseudowords), irrespective of task (speech production or 1-back matching). In left pSTS, activation was higher for non-semantic stimuli (pseudowords and hums) than semantic stimuli (words and object sounds) on the dorsal pSTS surface (dpSTS), irrespective of task. In left atSTS, activation was not sensitive to either semantic or verbal content. The contrasting response properties of left TPJ, dpSTS and atSTS was cross-validated in an independent sample of 59 participants, using region-by-condition interactions. We also show that each region participates in non-overlapping networks of frontal, parietal and cerebellar regions. Our results challenge previous claims about functional specialisation in the left posterior superior temporal lobe and motivate future studies to determine the timing and directionality of information flow in the brain networks involved in speech perception and production.
A functional dissociation of the left frontal regions that contribute to single word production tasks
(2021) Ekert, Justyna O.; Lorca-Puls, Diego L.; Gajardo-Vidal, Andrea; Criniond, Jennifer T.; Hope, Thomas M.H.; Greene, David W.; Price, Cathy J.
Controversy surrounds the interpretation of higher activation for pseudoword compared to word reading in the left precentral gyrus and pars opercularis. Specifically, does activation in these regions reflect: (1) the demands on sublexical assembly of articulatory codes, or (2) retrieval effort because the combinations of articulatory codes are unfamiliar? Using fMRI, in 84 neurologically intact participants, we addressed this issue by comparing reading and repetition of words (W) and pseudowords (P) to naming objects (O) from pictures or sounds. As objects do not provide sublexical articulatory cues, we hypothesis that retrieval effort will be greater for object naming than word repetition/reading (which benefits from both lexical and sublexical cues); while the demands on sublexical assembly will be higher for pseudoword production than object naming. We found that activation was: (i) highest for pseudoword reading [P>O&W in the visual modality] in the anterior part of the ventral precentral gyrus bordering the precentral sulcus (vPCg/vPCs), consistent with the sublexical assembly of articulatory codes; but (ii) as high for object naming as pseudoword production [P&O>W] in dorsal precentral gyrus (dPCg) and the left inferior frontal junction (IFJ), consistent with retrieval demands and cognitive control. In addition, we dissociate the response properties of vPCg/vPCs, dPCg and IFJ from other left frontal lobe regions that are activated during single word speech production. Specifically, in both auditory and visual modalities: a central part of vPCg (head and face area) was more activated for verbal than nonverbal stimuli [P&W>O]; and the pars orbitalis and inferior frontal sulcus were most activated during object naming [O>W&P]. Our findings help to resolve a previous discrepancy in the literature, dissociate three functionally distinct parts of the precentral gyrus, and refine our knowledge of the functional anatomy of speech production in the left frontal lobe.
Using transcranial magnetic stimulation of the undamaged brain to identify lesion sites that predict language outcome after stroke
(2017) Lorca-Puls, Diego L.; Gajardo-Vidal, Andrea; Seghier, Mohamed L.; Leff, Alexander P.; Sethi, Varun; Prejawa, Susan; Hope, Thomas M.H.; Devlin, Joseph T.; Price, Cathy J.
.Transcranial magnetic stimulation focused on either the left anterior supramarginal gyrus or opercular part of the left inferior frontal gyrus has been reported to transiently impair the ability to perform phonological more than semantic tasks. Here we tested whether phonological processing abilities were also impaired following lesions to these regions in right-handed, English speaking adults, who were investigated at least 1 year after a left-hemisphere stroke. When our regions of interest were limited to 0.5 cm3 of grey matter centred around sites that had been identified with transcranial magnetic stimulation-based functional localization, phonological impairments were observed in 74% (40/54) of patients with damage to the regions and 21% (21/100) of patients sparing these regions. This classification accuracy was better than that observed when using regions of interest centred on activation sites in previous functional magnetic resonance imaging studies of phonological processing, or transcranial magnetic stimulation sites that did not use functional localization. New regions of interest were generated by redefining the borders of each of the transcranial magnetic stimulation sites to include areas that were consistently damaged in the patients with phonological impairments. This increased the incidence of phonological impairments in the presence of damage to 85% (46/54) and also reduced the incidence of phonological impairments in the absence of damage to 15% (15/100). The difference in phonological processing abilities between those with and without damage to these ‘transcranial magnetic stimulation-guided’ regions remained highly significant even after controlling for the effect of lesion size. The classification accuracy of the transcranial magnetic stimulation-guided regions was validated in a second sample of 108 patients and found to be better than that for (i) functional magnetic resonance imaging-guided regions; (ii) a region identified from an unguided lesion overlap map; and (iii) a region identified from voxel-based lesion-symptom mapping. Finally, consistent with prior findings from functional imaging and transcranial magnetic stimulation in healthy participants, we show how damage to our transcranial magnetic stimulation-guided regions affected performance on phonologically more than semantically demanding tasks. The observation that phonological processing abilities were impaired years after the stroke, suggests that other brain regions were not able to fully compensate for the contribution that the transcranial magnetic stimulation-guided regions make to language tasks. More generally, our novel transcranial magnetic stimulation-guided lesion-deficit mapping approach shows how non-invasive stimulation of the healthy brain can be used to guide the identification of regions where brain damage is likely to cause persistent behavioural effects.

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