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Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa1-4. Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations3,5. Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80-20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch.
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População Negra , DNA Antigo , Genética Populacional , África Subsaariana , Arqueologia , População Negra/genética , População Negra/história , DNA Antigo/análise , Fluxo Gênico/genética , Genoma Humano/genética , História Antiga , HumanosRESUMO
The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease.
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Evolução Biológica , Ecologia/métodos , Hominidae/microbiologia , Metagenoma/genética , Microbiota/genética , Boca/microbiologia , África , Animais , Bactérias/classificação , Bactérias/genética , Biofilmes , Placa Dentária/microbiologia , Geografia , Gorilla gorilla/microbiologia , Hominidae/classificação , Humanos , Pan troglodytes/microbiologia , FilogeniaRESUMO
As management of upper gastrointestinal malignancies improves, and with popularization of bariatric surgery, endoscopists are likely to meet patients with altered upper gastrointestinal anatomy. Short-term, the surgery can cause complications like bleeding, leaks, and fistulas, and longer-term problems such as intestinal or biliary anastomotic strictures or biliary stones can arise, all necessitating endoscopy. In addition, the usual upper gastrointestinal pathologies can also still occur. These patients pose unique challenges. To proceed, understanding the new layout of the upper gastrointestinal tract is essential. The endoscopist, armed with a clear plan for navigation, can readily diagnose and manage most commonly occurring conditions, such as marginal ulcers and proximal anastomotic strictures with standard endoscopic instruments. With complex reconstructions involving long segments of small bowel, such as Roux-en-Y gastric bypass, utilization of balloon-assisted enteroscopy may be necessary, mandating modification of procedures such as endoscopic retrograde cholangiopancreatography. Successful endoscopic management of patients with altered anatomy will require prior planning and preparation to ensure the appropriate equipment, setting, and skill set is provided.
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Multiple autoantigens have been identified in membranous nephropathy (MN) by tissue-based proteomics. However, antigenic targets of disease are unknown for over 10% of patients with MN and over half of those with membranous lupus nephritis (MLN). Here, we identified multiple new targets in PLA2R-/THSD7A-/EXT-/NELL1-quadruple negative MN biopsies through mass spectrometry of immune complexes recovered from biopsy tissue of patients with MN. Patients with MN negative for these four antigens were identified from Arkana Laboratories case archives. Protein G immunoprecipitation recovered immune complexes from frozen biopsy tissue from 142 quadruple-negative cases and 278 cases of known antigen type, followed by interrogation by mass spectrometry. Potential putative antigens were confirmed through paraffin immunofluorescence and co-localization with IgG within immune deposits. Consecutive series of 165 cases of PLA2R-negative MN and 142 MLN biopsies were screened to determine the frequency for each potential antigen. Seven putative antigens were discovered within immune complexes from biopsies of patients with MN including FCN3, CD206, EEA1, SEZ6L2, NPR3, MST1, and VASN. Peptides from these proteins were not enriched in the 278 cases of known antigen type. Between three to 30 unique peptides were detected for each new target. Frequencies of each biomarker, determined by staining consecutive case series, ranged from under 1 to 4.9%. NPR3 and CD206 were only positive in index cases. All cases showed co-localization of IgG within the immune deposits. Thus, seven putative antigens were newly identified in MN and MLN. Due to the number of antigens identified, it is becoming impractical to type PLA2R-negative MN or MLN cases through immunostaining alone. A multiplex approach is needed for subtyping of these diseases.
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Glomerulonefrite Membranosa , Nefrite Lúpica , Humanos , Complexo Antígeno-Anticorpo , Espectrometria de Massas , Imunoglobulina G , Autoanticorpos , Receptores da Fosfolipase A2 , Proteínas de MembranaRESUMO
BACKGROUND: Human immunodeficiency virus (HIV) severely damages the epithelial cells of the gut lining leading to an inflamed leaky gut, translocation of microbial products, and dysbiosis resulting in systemic immune activation. Also, microbiota composition and maternal gut function can be altered in pregnancy through changes in the immune system and intestinal physiology. The aim of this study was to investigate the gut microbiota in HIV-infected and HIV-uninfected pregnant women and to compare and identify the association between gut microbial composition and adverse birth outcomes. RESULTS: A total of 94 pregnant women (35 HIV-infected and 59 HIV-uninfected controls) were recruited in Harare from 4 polyclinics serving populations with relatively poor socioeconomic status. Women were of a median age of 28 years (interquartile range, IQR: 22.3-32.0) and 55% of women were 35 weeks gestational age at enrolment (median 35.0 weeks, IQR: 32.5-37.2). Microbiota profiling in these participants showed that species richness was significantly lower in the HIV-infected pregnant women compared to their HIV-uninfected peers and significant differences in ß-diversity using Bray-Curtis dissimilarity were observed. In contrast, there was no significant difference in α-diversity between immune-compromised (CD4+ < 350 cells/µL) and immune-competent HIV-infected women (CD4+ ≥ 350 cells/µL) even after stratification by viral load suppression. HIV infection was significantly associated with a reduced abundance of Clostridium, Turicibacter, Ruminococcus, Parabacteroides, Bacteroides, Bifidobacterium, Treponema, Oscillospira, and Faecalibacterium and a higher abundance of Actinomyces, and Succinivibrio. Low infant birth weight (< 2500 g) was significantly associated with high abundances of the phylum Spirochaetes, the families Spirochaeteceae, Veillonellaceae, and the genus Treponema. CONCLUSION: The results reported here show that the species richness and taxonomy composition of the gut microbiota is altered in HIV-infected pregnant women, possibly reflecting intestinal dysbiosis. Some of these taxa were also associated with low infant birth weight.
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Microbioma Gastrointestinal , Infecções por HIV , Lactente , Gravidez , Humanos , Feminino , HIV , Resultado da Gravidez , Infecções por HIV/microbiologia , Peso ao Nascer , Disbiose , Região de Recursos Limitados , ZimbábueRESUMO
BACKGROUND: Despite the availability of an effective vaccine, chronic hepatitis B virus (HBV) infections remain a major cause of liver cirrhosis and hepatocellular carcinoma. HBV burden in pregnancy, risk factors and the timing of mother to child transmission remain poorly described especially during this era of lifelong use of Tenofovir/Lamivudine/Efavirenz as firstline for HIV treatment. We aimed to determine the burden of HBV in pregnancy and infants receiving their first dose of HBV vaccine 6 weeks after birth in a high HIV-prevalence setting. METHODS: Pregnant women ≥ 20 weeks' gestational age were enrolled and followed up as mother-infant dyads from delivery, 6, 24 and 96 weeks after birth. HBV surface antigen (HBsAg) was tested (fresh plasma, immunochromatography) in pregnancy. Women testing HBsAg-seropositive were further evaluated for other four HBV-biomarkers. Maternally HBV exposed babies were tested for HBsAg from birth and HBs-antibodies from 6 months of age. Maternal-infant factors were tested in univariable and multivariable analyses for predictors of HBsAg-seropositivity. RESULTS: Six hundred HIV-uninfected and 608 HIV-infected women on Tenofovir/Lamivudine/Efavirenz-regimen with median (interquartile range) 350: (87-1477) days of therapy use were enrolled. The overall HBsAg-seroprevalence was 32/1208: 2.65%, 95% confidence interval (CI) [1.74, 3.55]; being 7/600: 1.17%, 95% CI [0.37, 1.97] and 25/608: 4.11%, 95% CI [2.52, 5.68] in HBsAg-monoinfected and HBsAg/HIV-coinfected respectively, disproportionately detected in 31/32: 96.9%, 95% CI [90.8, 100] women presumably HBV-unvaccinated in infancy. HBV exposed babies tended to be born prematurely (< 37 weeks); 15.2% versus 9.9% in the HBV-unexposed, p = 0.009. In multivariate logistic regression-models with variable elimination, HIV-infection and reported tooth extractions predicted antenatal HBsAg-seropositivity; odds ratios (CI): 3.85 (1.61-10.7) and 2.46 (1.07-5.34), respectively. None of the exposed infants were HBsAg-seropositive neither before nor after 6 weeks of age. No HBs-antibodies were detected in 23.3% of HBsAg-exposed infants at two years despite having successfully completed the HBV vaccination schedule. CONCLUSION: Low and moderate HBV endemics were observed in HIV-uninfected and HIV-infected pregnant women, respectively. This underscores the need to routinely screen for HBV in pregnancy, especially the HIV-infected attending antenatal-care. Being HIV-infected and reported tooth extractions were independent risk factors for maternal HBsAg-seropositivity. Vertical and child horizontal transmissions were both absent, probably due to ~ the 50% frequency of antenatal anti-HBe-antibodies observed. Of concern was the absence of anti-HBs-antibodies in 23.3% of fully vaccinated/maternally HBV-exposed infants by two years. Absence of molecular diagnosis may have underestimated HBV burden. TRIAL REGISTRATION: www. CLINICALTRIALS: gov , trial registration number: NCT04087239.
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Infecções por HIV , Hepatite B Crônica , Hepatite B , Complicações Infecciosas na Gravidez , Lactente , Criança , Feminino , Gravidez , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/tratamento farmacológico , Resultado da Gravidez , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Lamivudina/uso terapêutico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Prevalência , Estudos Soroepidemiológicos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Fatores de Risco , Tenofovir/uso terapêutico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Vacinas contra Hepatite B , Anticorpos Anti-Hepatite B , MãesRESUMO
BACKGROUND: Acute kidney injury (AKI) is a major burden among hospitalized and critical care patients. Among hospitalized patients that progress to severe AKI there is increased risk for morbidity, mortality, and the need for renal replacement therapy (RRT). As there are no specific treatments for AKI, the discovery of novel biomarkers that predict the progression of AKI may aid in timely implementation of supportive care to improve outcomes. METHODS: We collected urine from 204 patients that developed Stage 1 AKI by AKIN criteria within 72 h following cardiothoracic surgery. Urine samples were collected at the time of the initial diagnosis of AKI and stored at -80° C. Among the 204 patients, 25 progressed to a composite primary outcome of Stage 3 AKI, requirement of RRT, or 30-day mortality. The remaining 179 patients did not progress beyond Stage 2 AKI and were considered controls. Urinary concentrations of SOD1 and SOD1 activity were measured following collection of all samples. Samples were thawed and urinary superoxide dismutase 1 (SOD1) concentrations were measured by sandwich ELISA and urinary SOD1 activity was measured through a commercially available colorimetric assay. RESULTS: Urinary concentrations of SOD1 were significantly elevated (67.0 ± 10.1 VS 880.3 ± 228.8 ng/ml, p < 0.0001) in patients that progressed to severe AKI and were able to predict the progression to severe AKI (AUC - 0.85, p < 0.0001). Furthermore, total SOD activity also increased in the urine of patients that required RRT (77.6% VS 49.81% median inhibition, p < 0.01) and was able to predict the need for RRT (AUC: 0.83, p < 0.01). CONCLUSION: These findings show that urinary SOD1 concentrations and SOD activity are novel prognostic biomarkers for severe AKI following cardiothoracic surgery.
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Injúria Renal Aguda , Humanos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Biomarcadores/urina , Prognóstico , Terapia de Substituição Renal , Superóxido Dismutase-1RESUMO
Platelet-dependent mechanisms for excessive clotting and bleeding in CKD remain undefined. Moreover, platelets' contribution to inflammation, and specifically to CKD, are equally elusive. To date, descriptions of changes in the functional properties of circulating platelets during CKD have provided confusing interpretations. Experimental approaches that can advance our understanding of platelet dysfunction in CKD are needed, and studies that provide mechanistic insights into the dynamic relationships between thrombosis, bleeding, and inflammation associated with CKD will be essential to improve clinical management and outcomes for this vulnerable population. This article summarizes existing literature characterizing platelets in CKD and identifies areas that need further investigation.
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BACKGROUND: Identification of target antigens PLA2R, THSD7A, NELL1, or Semaphorin-3B can explain the majority of cases of primary membranous nephropathy (MN). However, target antigens remain unidentified in 15%-20% of patients. METHODS: A multipronged approach, using traditional and modern technologies, converged on a novel target antigen, and capitalized on the temporal variation in autoantibody titer for biomarker discovery. Immunoblotting of human glomerular proteins followed by differential immunoprecipitation and mass spectrometric analysis was complemented by laser-capture microdissection followed by mass spectrometry, elution of immune complexes from renal biopsy specimen tissue, and autoimmune profiling on a protein fragment microarray. RESULTS: These approaches identified serine protease HTRA1 as a novel podocyte antigen in a subset of patients with primary MN. Sera from two patients reacted by immunoblotting with a 51-kD protein within glomerular extract and with recombinant human HTRA1, under reducing and nonreducing conditions. Longitudinal serum samples from these patients seemed to correlate with clinical disease activity. As in PLA2R- and THSD7A- associated MN, anti-HTRA1 antibodies were predominantly IgG4, suggesting a primary etiology. Analysis of sera collected during active disease versus remission on protein fragment microarrays detected significantly higher titers of anti-HTRA1 antibody in active disease. HTRA1 was specifically detected within immune deposits of HTRA1-associated MN in 14 patients identified among three cohorts. Screening of 118 "quadruple-negative" (PLA2R-, THSD7A-, NELL1-, EXT2-negative) patients in a large repository of MN biopsy specimens revealed a prevalence of 4.2%. CONCLUSIONS: Conventional and more modern techniques converged to identify serine protease HTRA1 as a target antigen in MN.
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Membranous lupus nephritis is a frequent cause of nephrotic syndrome in patients with systemic lupus erythematosus. It has been shown in phospholipase A2 receptor positive membranous nephropathy that known antibodies can be detected within sera, determination of the target autoantigen can have diagnostic significance, inform prognosis, and enable non-invasive monitoring of disease activity. Here we utilized mass spectrometry for antigen discovery in laser captured microdissected glomeruli from formalin-fixed paraffin embedded tissue and tissue protein G immunoprecipitation studies to interrogate immune complexes from frozen kidney biopsy tissue. We identified neural cell adhesion molecule 1 (NCAM1) to be a target antigen in some cases of membranous lupus nephritis and within rare cases of primary membranous nephropathy. The prevalence of NCAM1 association was 6.6% of cases of membranous lupus nephritis and in 2.0% of primary membranous nephropathy cases. NCAM1 was found to colocalize with IgG within glomerular immune deposits by confocal microscopy. Additionally, serum from patients with NCAM1-associated membranous nephropathy showed reactivity to NCAM1 recombinant protein on Western blotting and by indirect immunofluorescence assay, demonstrating the presence of circulating antibodies. Thus, we propose that NCAM1 is a target autoantigen in a subset of patients with membranous lupus nephritis. Future studies are needed to determine whether anti-NCAM1 antibody levels correlate with disease activity or response to therapy.
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Glomerulonefrite Membranosa , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Autoantígenos , Antígeno CD56 , Glomerulonefrite Membranosa/diagnóstico , Humanos , Moléculas de Adesão de Célula NervosaRESUMO
Patients with membranous nephropathy have an increased risk of malignancy compared to the general population, but the target antigen for malignancy-associated membranous nephropathy is unknown. To explore this, we utilized mass spectrometry for antigen discovery in malignancy-associated membranous nephropathy examining immune complexes eluted from frozen kidney biopsy tissue using protein G bead immunoglobulin capture. Antigen discovery was performed comparing cases of membranous nephropathy of unknown and known type. Mass spectrophotometric analysis revealed that nerve epidermal growth factor-like 1 (NELL1) immune complexes were uniquely present within the biopsy tissue in membranous nephropathy. Additional NELL1-positive cases were subsequently identified by immunofluorescence. In a consecutive series, 3.8% of PLA2R- and THSD7A-negative cases were NELL1-positive. These NELL1-positive cases had segmental to incomplete IgG capillary loop staining (93.4%) and dominant or co-dominant IgG1-subclass staining (95.5%). The mean age of patients with NELL1-positive membranous nephropathy was 66.8 years, with a slight male predominance (58.2%) and 33% had concurrent malignancy. Compared with PLA2R- and THSD7A-positive cases of membranous nephropathy, there was a greater proportion of cases with malignancies in the NELL1-associated group. Thus, NELL1-associated membranous nephropathy has a unique histopathology characterized by incomplete capillary loop staining, IgG1-predominance, and is more often associated with malignancy than other known types of membranous nephropathy.
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Glomerulonefrite Membranosa , Neoplasias , Idoso , Autoanticorpos , Proteínas de Ligação ao Cálcio , Humanos , Imunoglobulina G , Masculino , Receptores da Fosfolipase A2 , TrombospondinasRESUMO
AIMS: Using a pre-planned post hoc analysis of patients included in X-VeRT, we evaluated predictors of sinus rhythm at 6 weeks after planned cardioversion. METHODS AND RESULTS: Receiver operating characteristic curves and logistic regression models were used to evaluate continuous and categorical variables as predictors of sinus rhythm 6 at weeks from cardioversion (end of study). The primary analysis was performed in successfully cardioverted patients with an evaluable electrocardiogram at end of study. A second analysis evaluated additional patients who spontaneously restored sinus rhythm before planned cardioversion. Of the 1504 patients with atrial fibrillation of >48 h or of unknown duration who were randomly assigned to either rivaroxaban or vitamin K antagonist, 1039 (64.6 ± 10.3 years, 73.4% male) underwent planned cardioversion and were included in this study. Patients receiving early cardioversion (i.e. between 1 and 5 days from hospitalization) had a 67% higher probability to have sinus rhythm at end of study than those who received delayed cardioversion (i.e. between 21 and 56 days from hospitalization) [odds ratio (OR) 1.67, confidence interval (CI) 1.27-2.18; P < 0.0001]. In a multivariate analysis of 17 baseline variables, patients with a CHADS2 score of 0 were 33% less likely to be in sinus rhythm than those with a CHADS2 score ≥2 (OR 0.66, CI 0.47-0.94; P = 0.0225). In the secondary analysis, spontaneous restoration of sinus rhythm was also found to predict sinus rhythm at end of study (OR 8.62, CI 1.54-48.16; P = 0.0142). CONCLUSION: In X-VeRT, early cardioversion and high CHADS2 scores predicted sinus rhythm at 6 weeks from cardioversion.
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Fibrilação Atrial , Cardioversão Elétrica , Idoso , Anticoagulantes , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rivaroxabana , Resultado do TratamentoRESUMO
Membranous-like glomerulopathy with masked IgG kappa deposits (MGMID) is a recently described pattern of glomerulonephritis with a unique histopathology. The pattern is characterized by subepithelial and/or mesangial immune deposits that are "masked", to immunoglobulin staining by routine immunofluorescence but strongly stain for IgG and kappa light chain after protease digestion. Patients with this pattern of glomerulonephritis are most commonly young females presenting with proteinuria and a vague history of autoimmune disease such as low titer antinuclear antibodies. Here we compared the mass spectrometry profile of laser capture microdissected glomeruli from nine MGMID renal biopsies with eight biopsies showing other patterns of membranous glomerulopathy. The protein most significantly increased in MGMID was serum amyloid P. Immunostaining showed serum amyloid P colocalized with IgG in the glomeruli of MGMID but not with PLA2R-associated membranous glomerulopathy. Serum amyloid P was positive in the glomeruli of all 32 MGMID biopsies but negative in biopsies of other types of membranous glomerulopathies such as those associated with PLA2R and THSD7A. There were four biopsies with glomerular serum amyloid P staining among the 173 biopsies that did not fulfill criteria for MGMID or amyloidosis. All four of these biopsies with positive serum amyloid P staining had a membranous pattern of glomerulopathy with IgG kappa deposits that only differed from MGMID by the lack of "masking". Thus, positive staining within glomerular deposits for serum amyloid P identifies a unique form of glomerulonephritis likely sharing a common pathophysiologic mechanism of disease.
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Glomerulonefrite Membranosa , Glomerulonefrite , Nefropatias , Feminino , Glomerulonefrite Membranosa/diagnóstico , Humanos , Imunoglobulina G , Glomérulos RenaisRESUMO
The gut microbiome is composed of a diverse population of bacteria that have beneficial and adverse effects on human health. The microbiome has recently gained attention and is increasingly noted to play a significant role in health and a number of disease states. Increasing urea concentration during chronic kidney disease (CKD) leads to alterations in the intestinal flora that can increase production of gut-derived toxins and alter the intestinal epithelial barrier. These changes can lead to an acceleration of the process of kidney injury. A number of strategies have been proposed to interrupt this pathway of injury in CKD. The purpose of this review is to summarize the role of the gut microbiome in CKD, tools used to study this microbial population, and attempts to alter its composition for therapeutic purposes.
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Bactérias/metabolismo , Microbioma Gastrointestinal , Intestinos/microbiologia , Rim/metabolismo , Insuficiência Renal Crônica/microbiologia , Ureia/metabolismo , Uremia/microbiologia , Animais , Suplementos Nutricionais , Interações Hospedeiro-Patógeno , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Intestinos/fisiopatologia , Rim/fisiopatologia , Permeabilidade , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/terapia , Uremia/metabolismo , Uremia/fisiopatologia , Uremia/terapiaRESUMO
Deep networks are now able to achieve human-level performance on a broad spectrum of recognition tasks. Independently, neuromorphic computing has now demonstrated unprecedented energy-efficiency through a new chip architecture based on spiking neurons, low precision synapses, and a scalable communication network. Here, we demonstrate that neuromorphic computing, despite its novel architectural primitives, can implement deep convolution networks that (i) approach state-of-the-art classification accuracy across eight standard datasets encompassing vision and speech, (ii) perform inference while preserving the hardware's underlying energy-efficiency and high throughput, running on the aforementioned datasets at between 1,200 and 2,600 frames/s and using between 25 and 275 mW (effectively >6,000 frames/s per Watt), and (iii) can be specified and trained using backpropagation with the same ease-of-use as contemporary deep learning. This approach allows the algorithmic power of deep learning to be merged with the efficiency of neuromorphic processors, bringing the promise of embedded, intelligent, brain-inspired computing one step closer.
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BACKGROUND: Medical practice trends and limitations in trainees' duty hours have diminished the interest and exposure of nephrology fellows to percutaneous kidney biopsy (PKB). We hypothesized that an integrated nephrology-pathology-led simulation may be an effective educational tool. MATERIALS AND METHODS: A 4-hour PKB simulation workshop (KBSW), led by two ultrasonography (US)-trained nephrologists and two nephropathologists, consisted of 6 stations: 1) diagnostic kidney US with live patients, 2) kidney pathology with plasticine models of embedded torso cross-sections, 3) US-based PKB with mannequin (Blue Phantom™), 4) kidney pathology with dissected cadavers, 5) US-based PKB in lightly-embalmed cadavers, and 6) tissue retrieval adequacy examination by microscope. A 10-question survey assessing knowledge acquisition and procedural confidence gain was administered pre- and post-KBSW. RESULTS: 21 participants attended the KBSW and completed the surveys. The overall percentage of correct answers to knowledge questions increased from 55 to 83% (p = 0.016). The number of "extremely confident" answers increased from 0 - 5% to 19 - 28% in all 4 questions (p = 0.02 - 0.04), and the number of "not at all confident" answers significantly decreased from 14 - 62% to 0 - 5% in 3 out of 4 questions (p = 0.0001 - 0.03). Impact of the imparted training on subsequent practice pattern was not assessed. CONCLUSION: A novel KBSW is an effective educational tool to acquire proficiency in PKB performance and could help regain interest among trainees in performing PKBs.â©.
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Competência Clínica , Rim/diagnóstico por imagem , Rim/patologia , Nefrologia/educação , Treinamento por Simulação , Biópsia , Cadáver , Bolsas de Estudo , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Manequins , Autoeficácia , Inquéritos e Questionários , Ultrassonografia de IntervençãoRESUMO
Aminopeptidase A (APA) is expressed in glomerular podocytes and tubular epithelia and metabolizes angiotensin II (AngII), a peptide known to promote glomerulosclerosis. In this study, we tested whether APA expression changes in response to progressive nephron loss or whether APA exerts a protective role against glomerular damage and during AngII-mediated hypertensive kidney injury. At advanced stages of FSGS, fawn-hooded hypertensive rat kidneys exhibited distinctly increased APA staining in areas of intact glomerular capillary loops. Moreover, BALB/c APA-knockout (KO) mice injected with a nephrotoxic serum showed persistent glomerular hyalinosis and albuminuria 96 hours after injection, whereas wild-type controls achieved virtually full recovery. We then tested the effect of 4-week infusion of AngII (400 ng/kg per minute) in APA-KO and wild-type mice. Although we observed no significant difference in achieved systolic BP, AngII-treated APA-KO mice developed a significant rise in albuminuria not observed in AngII-treated wild-type mice along with increased segmental and global sclerosis and/or collapse of juxtamedullary glomeruli, microcystic tubular dilation, and tubulointerstitial fibrosis. In parallel, AngII treatment significantly increased the kidney AngII content and attenuated the expression of podocyte nephrin in APA-KO mice but not in wild-type controls. These data show that deficiency of APA increases susceptibility to glomerular injury in BALB/c mice. The augmented AngII-mediated kidney injury observed in association with increased intrarenal AngII accumulation in the absence of APA suggests a protective metabolizing role of APA in AngII-mediated glomerular diseases.