Death trends based on autopsy data compared to the beginning of the coronavirus pandemic in Brazil.

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.

Death trends based on autopsy data compared to the beginning of the coronavirus pandemic in Brazil

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.

Pathoarchitectonics of the cerebral cortex in chorea-acanthocytosis and Huntington's disease.

AIMS: Quantitative estimation of cortical neurone loss in cases with chorea-acanthocytosis (ChAc) and its impact on laminar composition. METHODS: We used unbiased stereological tools to estimate the degree of cortical pathology in serial gallocyanin-stained brain sections through the complete hemispheres of three subjects with genetically verified ChAc and a range of disease durations. We compared these results with our previous data of five Huntington's disease (HD) and five control cases. Pathoarchitectonic changes were exemplarily documented in TE1 of a 61-year-old female HD-, a 60-year-old female control case, and ChAc3. RESULTS: Macroscopically, the cortical volume of our ChAc cases (ChAc1-3) remained close to normal. However, the average number of neurones was reduced by 46% in ChAc and by 33% in HD (P = 0.03 for ChAc & HD vs. controls; P = 0.64 for ChAc vs. HD). Terminal HD cases featured selective laminar neurone loss with pallor of layers III, V and VIa, a high density of small, pale, closely packed radial fibres in deep cortical layers VI and V, shrinkage, and chromophilia of subcortical white matter. In ChAc, pronounced diffuse astrogliosis blurred the laminar borders, thus masking the complete and partial loss of pyramidal cells in layer IIIc and of neurones in layers III, V and VI. CONCLUSION: ChAc is a neurodegenerative disease with distinct cortical neurodegeneration. The hypertrophy of the peripheral neuropil space of minicolumns with coarse vertical striation was characteristic of ChAc. The role of astroglia in the pathogenesis of this disorder remains to be elucidated.

Prevalence of transactive response DNA-binding protein 43 (TDP-43) proteinopathy in cognitively normal older adults: systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review and meta-analysis on the prevalence of transactive response DNA-binding protein 43 (TDP-43) proteinopathy in cognitively normal older adults. METHODS: We systematically reviewed and performed a meta-analysis on the prevalence of TDP-43 proteinopathy in older adults with normal cognition, evaluated by the Mini-Mental State Examination or the Clinical Dementia Rating. We estimated the overall prevalence of TDP-43 using random-effect models, and stratified by age, sex, sample size, study quality, antibody used to assess TDP-43 aggregates, analysed brain regions, Braak stage, Consortium to Establish a Registry for Alzheimer's Disease score, hippocampal sclerosis and geographic location. RESULTS: A total of 505 articles were identified in the systematic review, and 7 were included in the meta-analysis with 1196 cognitively normal older adults. We found an overall prevalence of TDP-43 proteinopathy of 24%. Prevalence of TDP-43 proteinopathy varied widely across geographic location (North America: 37%, Asia: 29%, Europe: 14%, and Latin America: 11%). Estimated prevalence of TDP-43 proteinopathy also varied according to study quality (quality score >7: 22% vs. quality score <7: 42%), antibody used to assess TDP-43 proteinopathy (native: 18% vs. hyperphosphorylated: 24%) and presence of hippocampal sclerosis (without 24% vs. with hippocampal sclerosis: 48%). Other stratified analyses by age, sex, analysed brain regions, sample size and severity of AD neuropathology showed similar pooled TDP-43 prevalence. CONCLUSIONS: Different methodology to access TDP-43, and also differences in lifestyle and genetic factors across different populations could explain our results. Standardization of TDP-43 measurement, and future studies about the impact of genetic and lifestyle characteristics on the development of neurodegenerative diseases are needed.

Magnetic resonance diffusion tensor imaging for the pedunculopontine nucleus: proof of concept and histological correlation.

The pedunculopontine nucleus (PPN) has been proposed as target for deep brain stimulation (DBS) in patients with postural instability and gait disorders due to its involvement in muscle tonus adjustments and control of locomotion. However, it is a deep-seated brainstem nucleus without clear imaging or electrophysiological markers. Some studies suggested that diffusion tensor imaging (DTI) may help guiding electrode placement in the PPN by showing the surrounding fiber bundles, but none have provided a direct histological correlation. We investigated DTI fractional anisotropy (FA) maps from in vivo and in situ post-mortem magnetic resonance images (MRI) compared to histological evaluations for improving PPN targeting in humans. A post-mortem brain was scanned in a clinical 3T MR system in situ. Thereafter, the brain was processed with a special method ideally suited for cytoarchitectonic analyses. Also, nine volunteers had in vivo brain scanning using the same MRI protocol. Images from volunteers were compared to those obtained in the post-mortem study. FA values of the volunteers were obtained from PPN, inferior colliculus, cerebellar crossing fibers and medial lemniscus using histological data and atlas information. FA values in the PPN were significantly lower than in the surrounding white matter region and higher than in areas with predominantly gray matter. In Nissl-stained histologic sections, the PPN extended for more than 10 mm in the rostro-caudal axis being closely attached to the lateral parabrachial nucleus. Our DTI analyses and the spatial correlation with histological findings proposed a location for PPN that matched the position assigned to this nucleus in the literature. Coregistration of neuroimaging and cytoarchitectonic features can add value to help establishing functional architectonics of the PPN and facilitate neurosurgical targeting of this extended nucleus.

d-serine levels in Alzheimer's disease: implications for novel biomarker development.

Alzheimer's disease (AD) is a severe neurodegenerative disorder still in search of effective methods of diagnosis. Altered levels of the NMDA receptor co-agonist, d-serine, have been associated with neurological disorders, including schizophrenia and epilepsy. However, whether d-serine levels are deregulated in AD remains elusive. Here, we first measured D-serine levels in post-mortem hippocampal and cortical samples from nondemented subjects (n=8) and AD patients (n=14). We next determined d-serine levels in experimental models of AD, including wild-type rats and mice that received intracerebroventricular injections of amyloid-ß oligomers, and APP/PS1 transgenic mice. Finally, we assessed d-serine levels in the cerebrospinal fluid (CSF) of 21 patients with a diagnosis of probable AD, as compared with patients with normal pressure hydrocephalus (n=9), major depression (n=9) and healthy controls (n=10), and results were contrasted with CSF amyloid-ß/tau AD biomarkers. d-serine levels were higher in the hippocampus and parietal cortex of AD patients than in control subjects. Levels of both d-serine and serine racemase, the enzyme responsible for d-serine production, were elevated in experimental models of AD. Significantly, d-serine levels were higher in the CSF of probable AD patients than in non-cognitively impaired subject groups. Combining d-serine levels to the amyloid/tau index remarkably increased the sensitivity and specificity of diagnosis of probable AD in our cohort. Our results show that increased brain and CSF d-serine levels are associated with AD. CSF d-serine levels discriminated between nondemented and AD patients in our cohort and might constitute a novel candidate biomarker for early AD diagnosis.

African ancestry protects against Alzheimer's disease-related neuropathology.

Previous studies in dementia epidemiology have reported higher Alzheimer's disease rates in African-Americans when compared with White Americans. To determine whether genetically determined African ancestry is associated with neuropathological changes commonly associated with dementia, we analyzed a population-based brain bank in the highly admixed city of São Paulo, Brazil. African ancestry was estimated through the use of previously described ancestry-informative markers. Risk of presence of neuritic plaques, neurofibrillary tangles, small vessel disease, brain infarcts and Lewy bodies in subjects with significant African ancestry versus those without was determined. Results were adjusted for multiple environmental risk factors, demographic variables and apolipoprotein E genotype. African ancestry was inversely correlated with neuritic plaques (P=0.03). Subjects with significant African ancestry (n=112, 55.4%) showed lower prevalence of neuritic plaques in the univariate analysis (odds ratio (OR) 0.72, 95% confidence interval (CI) 0.55-0.95, P=0.01) and when adjusted for age, sex, APOE genotype and environmental risk factors (OR 0.43, 95% CI 0.21-0.89, P=0.02). There were no significant differences for the presence of other neuropathological alterations. We show for the first time, using genetically determined ancestry, that African ancestry may be highly protective of Alzheimer's disease neuropathology, functioning through either genetic variants or unknown environmental factors. Epidemiological studies correlating African-American race/ethnicity with increased Alzheimer's disease rates should not be interpreted as surrogates of genetic ancestry or considered to represent African-derived populations from the developing nations such as Brazil.

Brazilian psychiatric brain bank: a new contribution tool to network studies.

There is an urgent need for expanding the number of brain banks serving psychiatric research. We describe here the Psychiatric Disorders arm of the Brain Bank of the Brazilian Aging Brain Study Group (Psy-BBBABSG), which is focused in bipolar disorder (BD) and obsessive compulsive disorder (OCD). Our protocol was designed to minimize limitations faced by previous initiatives, and to enable design-based neurostereological analyses. The Psy-BBBABSG first milestone is the collection of 10 brains each of BD and OCD patients, and matched controls. The brains are sourced from a population-based autopsy service. The clinical and psychiatric assessments were done by an expert team including psychiatrists, through an informant. One hemisphere was perfused-fixed to render an optimal fixation for conducting neurostereological studies. The other hemisphere was comprehensively dissected and frozen for molecular studies. In 20 months, we collected 36 brains. A final report was completed for 14 cases: 3 BDs, 4 major depressive disorders, 1 substance use disorder, 1 mood disorder NOS, 3 obsessive compulsive spectrum symptoms, 1 OCD and 1 schizophrenia. The majority were male (64%), and the average age at death was 67.2 ± 9.0 years. The average postmortem interval was 16 h. Three matched controls were collected. The pilot stage confirmed that the protocols are well fitted to reach our goals. Our unique autopsy source makes possible to collect a fairly number of high quality cases in a short time. Such a collection offers an additional to the international research community to advance the understanding on neuropsychiatric diseases.

Simulation of endoscopic third ventriculostomy in fresh cadaveric specimens.

OBJECTIVE: The purpose of this research is to describe and analyze the endoscopic anatomy of cerebral ventricles, especially of the lateral ventricle and third ventricle. METHODS: 47 brains of adult human cadavers were studied at the Death Check Unit (DCU) of São Paulo. Age, sex, day and approximate time of death, day and time of study, cause of death, outcome of puncture and number of attempts were recorded. A rigid neuroendoscope was utilized. The approach to the ventricular system was via the pre-coronal point on the right side. RESULTS: The number of individuals studied was 47, of which 22 (47%) were women and 25 (53%) were men. Age ranged from 20 to 95 years. The minimum time lag between the death and the study was 8 h and the maximum time was 29 h. Of the cadavers studied, three presented alterations in the central nervous system as the cause of death. Successful puncture was obtained in 42 (89%) being 72% in the first attempt. In the analysis performed by Fisher's exact test with a 5% level of significance, an association between the number of attempts (2) and the cause of cerebral death was found (p=0.018). CONCLUSIONS: The visualization of neural structures without bleeding, the possibility of training techniques such as third ventriculostomy, the development of new techniques and to help sctructure new concepts about anatomic landmarks have by far overcome the difficulties.

Hydroxyethyl starch is superior to lactated Ringer as a replacement fluid in a pig model of acute normovolaemic haemodilution.

BACKGROUND: Tissue tolerance to oxygen privation during acute normovolaemic haemodilution with different fluids remains unclear. We tested the hypothesis that hydroxyethyl starch (HES) is superior to lactated Ringer's solution in pigs for preserving tissue perfusion during acute normovolaemic haemodilution. METHODS: Twenty-four animals were randomized into control, lactated Ringer's solution and HES groups. All groups, except the control, underwent acute normovolaemic haemodilution. Haemodynamics, oxygen parameter indices, global anaerobic metabolic markers, echocardiographic parameters, gastric tonometry and serum osmolarity were monitored at baseline, immediately after (0 min) and 60 and 120 min after the end of haemodilution. Myocardial, liver, stomach and intestine samples were collected for further evaluation. RESULTS: Cardiac and oxygen parameter index responses to acute normovolaemic haemodilution were comparable. However, the increment in cardiac index, stroke volume index, and left ventricular stroke work index were more sustained in the starch group. In the lactated Ringer's group, gastric pH decreased significantly and was accompanied by a significant increase in lactate. Myocardial ultrastructure was better preserved in the starch group. The other tissue samples presented no change. CONCLUSIONS: In this model of ANH, the starch group had a superior haemodynamic response. Minor loss of myocardial cellular integrity and preserved gastric pHi reinforce these findings.

Oxidized thiols markedly amplify the vascular response to balloon injury in rabbits through a redox active metal-dependent pathway.

OBJECTIVE: Our aim was to assess whether exposure to oxidized thiols--a known usual consequence of oxidant stress--has the potential to affect the vascular repair response to angioplasty-induced injury. In addition, we also assessed the role of redox active metals in disulfide effects. METHODS: In 82 rabbits submitted to overdistention of iliac arteries, the following variables were analyzed: neointimal thickening, immunoreactivity to Proliferating Cell Nuclear Antigen, and cellular and collagen densities. RESULTS: A single intraarterial challenge of oxidized glutathione (GSSG, 6.5 mumol/kg) during and immediately after injury triggered a marked increase of the vascular repair reaction, as follows: (A) at day 7 after injury, there was a 2.7-fold increase in proliferation (p < 0.001 vs. control); (B) at day 14, there was increase of intimal/medial area ratio to 1.35 +/- 0.14, vs. 0.56 +/- 0.08 in controls. Proliferating cells increased to 5.5 +/- 0.8 cells/mm2, vs. 2.2 +/- 0.5 in controls (p < 0.002 for both variables). Overall cellularity was enhanced 2.2-fold; (C) at day 28, there was ongoing vessel wall proliferation, contrarily to controls. All GSSG effects were completely prevented by co-infusion of reduced glutathione (GSH) and were mimicked by cystine (6.5 mumol/kg). The uninjured artery showed no response to disulfides. To assess the role of redox active metals in GSSG action, the effects of 1,10-phenanthroline or N-CBZ-Pro-Leu-Gly hydroxamic acid (HXA), metal chelators with metalloproteinase inhibitor properties, were evaluated. Both compounds totally blocked the GSSG-induced amplification of vascular responses. In rabbits not exposed to GSSG, HXA decreased neointimal thickening by 50% (p < 0.05). CONCLUSIONS: Exposure to excess disulfide levels early after vascular balloon injury markedly amplified the late cellular response through interaction with redox active metals. These pathways can potentially mediate noxious effects of oxidative stress in vessels.

Effects of a single heparin bolus on neointimal growth after arterial injury in intact rabbits.

Heparinization is a routine procedure during angioplasty; however, its consequences on the late vascular response to a severe injury are unclear. The authors' objective was to explore the effect of a single heparin bolus at the time of a severe vascular injury on late intimal proliferation and neointimal thickening. The iliac artery of 57 normolipemic rabbits was overdistended with a balloon catheter. Heparin (250 IU/kg i.v.) was given to 29 rabbits ten minutes before angioplasty, whereas 28 rabbits served as untreated controls. Neointimal thickening was prominent at fourteen days after injury and reached near-maximal values at day 28. The intimal/medial area ratio was reduced by an average 28.3% with heparin (at day 28: 2.19 +/- 0.51 vs 1.57 +/- 0.59, control vs heparin, P = 0.02). Neointimal cells stained positively for HHF-35 antibody, directed against smooth muscle cell antigens. Neointimal proliferation, quantified through the number of cell nuclei peroxidase-stained for PCNA/cyclin antigen, was significantly decreased by 43% and 49% with heparin, respectively, at days 7 and 14 after injury. These data suggest that early exposure even to low doses of heparin accounts for much of its inhibitory effect in vascular response to injury; such an effect might prove important in interpreting results of human trials of interventions against restenosis.

[Medical pedagogy and special didactics in graduate courses at the medical school of the University of São Paulo, Brazil]. / As disciplinas de didática especial e de pedagogia médica no curso de pós-graduação da Faculdade de Medicina da Universidade de S. Paulo.

Graduate courses of medical pedagogy and special didactics at S. Paulo University Medical School are analysed. The authors present objectives, subject matters and methodologies of both courses, as well as their evaluation by the graduate students. After an initial rejection, the evaluation became very positive (67% in medical pedagogy and 82% in special didactics). Some future perspectives are discussed.

Biological effects of air pollution in São Paulo and Cubatão.

Rats were used as biological indicators of air quality in two heavily polluted Brazilian towns: São Paulo and Cubatão. They were exposed for 6 months to ambient air in areas where the pollution was known to be severe. The following parameters were studied and compared to those of control animals: respiratory mechanics, mucociliary transport, morphometry of respiratory epithelium and distal air spaces, and general morphological alterations. The results showed lesions of the distal and upper airways in rats exposed in Cubatão, whereas the animals from São Paulo showed only alterations of the upper airways but of greater intensity than those observed in the Cubatão group. There are both qualitative and quantitative differences in the pollutants of these places: in São Paulo automobile exhaust gases dominate and in Cubatão the pollution is due mainly to particulates of industrial sources. The correlation of the pathological findings with the pollutants is discussed and it is concluded that biological indicators are useful to monitor air pollutions which reached dangerous levels in São Paulo and Cubatão.

Laser surgery in enclosed spaces: a review.

We describe the results of experiments carried out in the arteries of dogs, rabbits, guinea pigs, and humans, normal or atheromatous, calcified, or not, with the application of the argon and CO2 laser, in vitro or in vivo, directly or indirectly. Similarly, we present the results of laser effects when radiation is delivered through a special catheter with the purpose of producing aortic insufficiency, opening pulmonary valvular stenosis, desobstructing carotid and coronary obstruction induced in dogs as well as atheromatous obstructions in human amputated legs. Arterial wall perforation was present in 50% of all cases. We suggest four options in order to diminish this adverse result: (1) the use of coherent optical bundles which will allow the proper guiding of the laser beam, (2) the construction of a special catheter for proper handling of the laser-carrying fiber, (3) a combination of optical and computer programs which will aid to identify calcified regions, and (4) the use of dyes which will be strongly and selectively absorbed by the atheromas and which will thus allow their destruction at low laser powers.