Search

Several biomarkers have been evaluated as predictors of severity or in directing the treatment of COVID-19, however there are no conclusive results with prediction of the pathobiology of the infection. In this study, we evaluated serum levels of cytokines, chemokines, and cell growth factors in association with the pathobiology of mild to moderate SARS-CoV-2 infection. Those markers may act as immuno-inflammatory biomarkers in adults with mild to moderate flu syndrome who sought care at health units. Serum levels of SARS-CoV-2 infected patients (n=113) and flu symptoms individuals negative for SARS-CoV-2 (n=58), tested by the RT-qPCR test - nasal swab were compared to healthy controls (n=53). Participants who were symptomatic but negative for SARS-CoV-2 were tested for Influenza A/B and Respiratory Syncytial Virus (RSV). Results showed that the pro-inflammatory cytokines IL-1β, MCP-3, TNF-α and G-CSF were increased in symptomatic patients and the cytokines IL-6 and IL-10 were associated with patients positive for SARS-CoV-2 when compared to healthy controls. Symptoms associated with COVID-19 were fever, anosmia, ageusia and myalgia. For patients without SARS-CoV-2 infection their major symptom was sore throat. Five percent (4/83) of SARS-CoV-2 negative patients were positive for RSV. The pathobiology of mild to moderate SARS-CoV-2 infection was associated with increasing pro-inflammatory cytokines and also a pleiotropic IL-6 and anti-inflammatory IL-10 cytokines compared to healthy controls.

We adopted the reverse-transcriptase-loop-mediated isothermal amplification (RT-LAMP) to detect severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) in patient samples. Two primer sets for genes N and Orf1ab were designed to detect SARS-CoV-2, and one primer set was designed to detect the human gene Actin. We collected prospective 138 nasopharyngeal swabs, 70 oropharyngeal swabs, 69 salivae, and 68 mouth saline wash samples from patients suspected to have severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 to test the RT-LAMP in comparison with the gold standard technique reverse-transcription quantitative polymerase chain reaction (RT-qPCR). The accuracy of diagnosis using both primers, N5 and Orf9, was evaluated. Sensitivity and specificity for diagnosis were 96% (95% confidence interval [CI]: 87-99) and 85% (95% CI: 76-91) in 138 samples, respectively. Accurate diagnosis results were obtained only in nasopharyngeal swabs processed via extraction kit. Accurate and rapid diagnosis could aid coronavirus disease 2019 (COVID-19) pandemic management by identifying, isolating, and treating patients rapidly.

Few studies have focused on nutrient-deficient diets and associated pathobiological dynamics of body composition and intestinal barrier function. This study evaluated the impact of a nutrient-deficient diet on physical development and intestinal morphofunctional barrier in mice. C57BL/6 (21 days of age) mice were fed a Northeastern Brazil regional basic diet (RBD) or a control diet for 21 d. The animals were subjected to bioimpedance analysis, lactulose test, morphometric analysis and quantitative reverse transcription-PCR to evaluate tight junctions and intestinal transporters. RBD feeding significantly reduced weight (P < 0·05) from day 5, weight gain from day 3 and tail length from day 14. The intake of RBD reduced total body water, extracellular fluid, fat mass and fat-free mass from day 7 (P < 0·05). RBD induced changes in the jejunum, with an increase in the villus:crypt ratio on day 7, followed by reduction on days 14 and 21 (P < 0·05). Lactulose:mannitol ratio increased on day 14 (P < 0·05). Changes in intestinal barrier function on day 14 were associated with reductions in claudin-1 and occludin, and on day 21, there was a reduction in the levels of claudin-2 and occludin. SGLT-1 levels decreased on day 21. RBD compromises body composition and physical development with dynamic changes in intestinal barrier morphofunctional. RBD is associated with damage to intestinal permeability, reduced levels of claudin-1 and occludin transcripts and return of bowel function in a chronic period.

Acrolein is the main toxic metabolite of Ifosfamide (IFO) that causes urothelial damage by oxidative stress and inflammation. Here we investigate the molecular mechanism of action of gingerols, Zingiber officinale bioactive molecules, as an alternative treatment for ifosfamide-induced hemorrhagic cystitis. Female Swiss mice were randomly divided into 5 groups: control; IFO; IFO + Mesna; and IFO + [8]- or [10]-gingerol. Mesna (80 mg/kg, i.p.) was given 5 minutes before, 4 and 8 hours after IFO (400mg/kg, i.p.). Gingerols (25 mg/Kg, p.o.) were given 1 hour before and 4 and 8 hours after IFO. Animals were euthanized 12 hours after IFO injection. Bladders were submitted to macroscopic and histological evaluation. Oxidative stress and inflammation were assessed by malondialdehyde (MDA) or myeloperoxidase assays, respectively. mRNA gene expression was performed to evaluate Mesna and gingerols mechanisms of action. Mesna was able to protect bladder tissue by activating NF-κB and NrF2 pathways. However, we demonstrated that gingerols acted as an antioxidant and anti-inflammatory agent stimulating the production of IL-10, which intracellularly activated JAK/STAT/FOXO signaling pathway.

Lactulose and mannitol have been used to assess intestinal permeability and several methodologies have been used.ObjectivesThis study aimed to validate the high-performance liquid chromatography method coupled with tandem mass spectrometry to measure mannitol and lactulose sugars.Material and MethodsWe used a high-performance liquid chromatography (HPLC) system coupled to an ABsciex Q-TRAP 5500 triple quadrupole mass spectrometer (MS/MS) with an ABSciex Electro Nebulization Interface (ESI) (Framingham, MA, USA). For the separation of lactulose and mannitol compounds in the HLPC, the analytical column HILIC-ZIC® from ES Industries (West Berlin, USA) was used. The parameters analyzed for analytical validation were specificity/selectivity, linearity, LD, LQ accuracy, precision (repeatability and intermediate precision) and matrix effect.ResultsThe accuracy was demonstrated from the recovery at three concentration levels (100, 500 and 1000 ng/mL) and in triplicate, which showed recovery values above the recommended (>120%). Intermediate precision was determined at 24-hour intervals and the coefficients of variation found were less than 8.7%. The matrix effect was measured through the retention times in the standard samples and in the samples of the spiked standards in dilutions with urine samples, which varied between 99.3% and 100.3%. Urine samples from malnourished and healthy children were analyzed. The L:M ratio was considerably lower in the control group compared to the MN group (pConclusionsThe results showed that the HPLC-MS/MS method was sensitive, specific, and accurate for the determination of molecular biomarkers of lactulose and mannitol. In addition, the L:M test is a functional test capable of determining with high sensitivity the barrier function damage of the intestinal epithelium in children with malnutrition compared to health control children.

Background: A dysregulated inflammatory response contributes to decline in patients with COVID-19. This cross-sectional study evaluated biomarkers of unvaccinated patients admitted to the intensive care unit of a hospital in Fortaleza, Brazil. Methods: Twenty cytokines were quantified upon hospital admission; clinical and laboratory data were analyzed, as well as sociodemographic data, to search for an association with clinical outcomes, including fatal (n = 40) or recovered cases (n = 38). Results: Fatal cases exhibited significantly higher levels of IL-18 (p = 0.009); deceased patients were older (p = 0.0001), had a lower number of platelets (p = 0.0063) and higher neutrophil–lymphocyte ratio (p = 0.0230) than those who recovered. Conclusion: These findings indicate that IL-18 is a possible marker to predict poor prognosis in critically ill patients with COVID-19.

In Colombia, Lachesis acrochorda causes 2-3% of all snake envenomations. The accidents promote a high mortality rate (90%) due to blood and cardiovascular complications. Here, the effects of the snake venom of L. acrochorda (SVLa) were analyzed on human blood cells and on cardiovascular parameters of rats. SVLa induced blood coagulation, as measured by the prothrombin time test, but did not reduce the cell viability of neutrophils and platelets evaluated by the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and by the lactate dehydrogenase (LDH) enzyme assay. In fact, SVLa increased the absorbance in tests made with platelets subjected to the MTT assay. SVLa induced platelet aggregation whose magnitude was comparable to that of the positive control adenosine diphosphate (ADP), and occurred earlier with increasing SVLa concentration. Acetylsalicylic acid (ASA, a cyclooxygenase inhibitor) or clopidogrel (an ADP receptor blocker) inhibited the aggregating effect of SVLa. Inhibition of SVLa-elicited platelet aggregation also resulted from the treatment with disodium ethylenediaminetetraacetate (Na2-EDTA; metalloproteinase inhibitor) and with 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF, serine protease inhibitor). In isolated right atrium of rats, SVLa increased slightly, but significantly, the magnitude of the spontaneous contractions and, in isolated rat aorta, SVLa relaxed KCl- or phenylephrine-induced contractions. In vivo, SVLa induced hypotension and bradycardia in rats, with detection of hemorrhage in pulmonary and renal tissues. Altogether, under experimental conditions, SVLa induced blood coagulation, platelet aggregation, hypotension and bradycardia. Part of the effects presented here may be explained by the presence of snake venom metalloproteinases (SVMPs) and snake venom serine proteases (SVSPs), constituents of SVLa.

We adopted the reverse transcriptase - loop mediated isothermal amplification (RT-LAMP) to detect SARS-Cov-2 in patient samples. Two primer sets for genes N and Orf1ab were designed to detect SARS-CoV-2, and one primer set was designed to detect the human gene Actin. We collected prospective 138 nasopharyngeal swabs, 70 oropharyngeal swabs, 69 saliva, and 68 mouth saline wash samples from patients suspected to have severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 to test the RT-LAMP in comparison with the golden standard technique RT-qPCR. Accuracy of diagnosis using both primers, N5 and Orf9, was evaluated. Sensitivity and specificity for diagnosis was 96% (95% CI 87-99) and 85% (95% CI 76-91) in 138 samples, respectively. Accurate diagnosis results were obtained only in nasopharyngeal swab processed via extraction kit. Accurate and rapid diagnosis could aid COVID-19 pandemic management by identifying, isolating, and treating patients rapidly.HighlightsNew nucleic acid amplification test for the diagnosis of SARS-CoV-2 using the RT-LAMPN5 primer set showed mutations in strains of interest, such as the gamma strain (P.1) of SARS-CoV-2When evaluated in combination N5 and Orf9 primer sets maintained high sensitivity and specificity

This study aimed to evaluate the efficacy and toxicity of tenofovir (TDF) and TDF combined with emtricitabine (TDF/FTC) in patients with mild to moderate COVID-19 infections. We conducted a randomized, double-blind, placebo-controlled clinical trial in patients with clinical suspicion of mild to moderate respiratory infection caused by SARS-CoV-2 who were treated at an outpatient clinic. Patients were randomly recruited to take 10 days of TDF (300 mg/day), TDF (300 mg/day) combined with FTC (200 mg/day) or placebo Vitamin C (500 mg/day). The primary parameter was the score of symptoms and predictive signs of COVID-19, assessed on the seventh day of patient follow-up. From a total of 309 patients with clinical suspicion of SARS-CoV-2, 227 met the inclusion criteria and were randomly distributed into the following groups: (a) 75 (one did not initiate treatment) in the TDF group; (b) 74 in the TDF combined with FTC group; and (c) 77 in the Vitamin C group (placebo). Of the 226 patients, 139 (62%) were positive for SARS-CoV-2. Fever (≥37.8°C), ageusia or dysgeusia, anosmia or dysosmia, and two or more clinical symptoms or signs were significantly associated with SARS-CoV-2 infection. There was no significant change in clinical score based on clinical symptoms and signs between treatment groups. Patients with mild to moderate infection by SARS-CoV-2 had higher concentrations of G-CSF, IL-1β, IL-6 and TNF-α compared to patients without infection. Patients with mild to moderate respiratory infection, with fever (≥37.8°C), loss of smell, loss of taste and two or more symptoms, have a better prediction for the diagnosis of COVID-19. Patients with SARS-CoV-2 showed higher and more persistent proinflammatory cytokines profile compared to patients not infected with SARS-CoV-2. Pharmacological intervention with TDF or TDF combined with FTC did not change the clinical signs and symptoms score in mild to moderate respiratory infection in patients with SARS-CoV-2 compared to the Vitamin C group (placebo).

Background:Scorpion venom causes renal injury and affects vascular ion-channels function. Centruroides margaritatus scorpion is found in Colombia and is frequently the cause of envenomation accidents; however, its renal impact has never been investigated.Objective:To evaluate the effects of C. margaritatus venom (CmV) on renal parameters using isolated rat kidney and renal cell culture models.Methods:Wistar rats (n = 5, weighing 240-300 g) were first perfused with Krebs-Henseleit solution containing 6 g 100 mL-1 bovine serum albumin. After 30 minutes, the kidneys were perfused with CmV to a final concentration of 10 μgmL-1; evaluation was performed by measuring Perfusion Pressure (PP), Renal Vascular Resistance (RVR), Urinary Flow (UF), Glomerular Filtration Rate (GFR), and percentage of electrolyte tubular transport. Moreover, kidney histological analyses and cell cytotoxicity in renal tubule epithelial cells (MDCK) and proximal tubular cells (LLC-MK2) were assessed.Results:CmV increased PP and RVR 60 min after perfusion. On the other hand, UF, GFR, and the percentages of sodium, potassium and chloride tubular transport decreased after experimental envenomation. UF dropped after 120 min, while GFR and percentage of electrolyte tubular transport diminished after 60, 90 and 120 min. CmV was not toxic to MDCK cell line but reduced the viability of LLC-MK2 cells at concentrations ranging from 6.25 to 200 μgmL-1. Histological analyses disclosed hydropic degeneration, edema, and protein deposits. Flow cytometry disclosed that cell death occurred predominantly by necrosis.Conclusion:Our results suggest that C. margaritatus venom can trigger renal impairment, mainly in the proximal kidney tubule.

RESUMO A ordem dos Passeriformes é uma das mais pressionadas pelas ações antrópicas, especialmente as relativas ao tráfico de animais, que, devido às más condições de manejo e higiênico-sanitárias, favorecem a infecção dos espécimes por patógenos virulentos e zoonóticos, como cepas de Escherichia coli e Salmonella spp., cujo isolamento em suabes cloacais, bem como a análise dos genes de virulência das cepas de E. coli foram objetivos do estudo. Para isso, 120 Passeriformes silvestres nativos, recebidos pelo Cetas/CE, foram avaliados individualmente. As cepas isoladas foram submetidas a teste de disco difusão para determinação da sensibilidade aos antimicrobianos. Em etapa posterior, foi realizada PCR para a detecção de oito genes de virulência dos principais patotipos diarreiogênicos de E. coli. Quanto aos resultados, nenhuma cepa de Salmonella spp. foi isolada, no entanto a ocorrência de E. coli foi de 40,8%. Foi observada elevada resistência, principalmente aos antimicrobianos tetraciclina, ampicilina e sulfazotrim, ocorrendo multirresistência em 42,8% das cepas. Pela análise molecular, foram diagnosticados quatro entre os nove genes pesquisados, com a identificação de EPEC típicas, EPEC atípicas, ETEC, EHEC e EAEC. Os resultados apontam para a importância de Passeriformes como possíveis disseminadores de zoonoses.

Background Environmental enteric dysfunction (EED) is thought to increase the risk of micronutrient deficiencies, but few studies adjust for dietary intakes and systemic inflammation. Objective We tested whether EED is associated with micronutrient deficiency risk independent of diet and systemic inflammation, and whether it mediates the relation between intake and micronutrient status. Methods Using data from 1283 children in the MAL-ED (Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health) birth cohort we evaluated the risk of anemia, low retinol, zinc, and ferritin, and high transferrin receptor (TfR) at 15 mo. We characterized gut inflammation and permeability by myeloperoxidase (MPO), neopterin (NEO), and α-1-antitrypsin (AAT) concentrations from asymptomatic fecal samples averaged from 9 to 15 mo, and averaged the lactulose:mannitol ratio z-score (LMZ) at 9 and 15 mo. Nutrient intakes from complementary foods were quantified monthly from 9 to 15 mo and densities were averaged for analyses. α-1-Acid glycoprotein at 15 mo characterized systemic inflammation. Relations between variables were modeled using a Bayesian network. Results A greater risk of anemia was associated with LMZ [1.15 (95% CI: 1.01, 1.31)] and MPO [1.16 (1.01, 1.34)]. A greater risk of low ferritin was associated with AAT [1.19 (1.03, 1.37)] and NEO [1.22 (1.04, 1.44)]. A greater risk of low retinol was associated with LMZ [1.24 (1.08, 1.45)]. However, MPO was associated with a lower risk of high transferrin receptor [0.86 (0.74, 0.98)], NEO with a lower risk of low retinol [0.75 (0.62, 0.89)], and AAT with a lower risk of low plasma zinc [0.83 (0.70, 0.99)]. Greater nutrient intake densities (vitamins A and B6, calcium, protein, and zinc) were negatively associated with EED. Inverse associations between nutrient densities and micronutrient deficiency largely disappeared after adjustment for EED, suggesting that EED mediates these associations. Conclusions EED is independently associated with an increased risk of low ferritin, low retinol, and anemia. Greater nutrient density from complementary foods may reduce EED, and the control of micronutrient deficiencies may require control of EED.

Shigella/Enteroinvasive Escherichia coli (EIEC) pathotype is a major enteropathogen associated with diarrhea and malnutrition in children from developing countries. This study aimed to correlate Shigella/EIEC virulence-related genes (VRGs) with clinical symptoms, nutritional status and coenteropathogens in children from the Brazilian semiarid region. We designed a case-control study of community diarrhea in six cities of the Brazil semiarid region with 1200 children aging 2-36 months. Standardized questionnaire was applied for collecting sociodemographic, nutritional status and clinical information of the children. DNA samples were extracted from stools and diagnosed for Shigella/EIEC using PCR-based approaches. Positive samples were tested for 28 VRGs using four multiplex PCRs. Intestinal inflammation was determined by measuring fecal myeloperoxidase (MPO). Shigella/EIEC pathotype was detected in 5% of the children and was significantly associated with diarrhea. The genes sen (encoding Shigella enterotoxin 2), ipgB2, ipgB1 (both encoding type 3 secretion system-T3SS effectors that modulate actin filament), and ospF (encoding a T3SS effector involved in suppression of host responses) were further associated with diarrhea in Shigella/EIEC positive children. Among children presenting diarrhea, virA gene (encoding a T3SS effector that promotes microtubule destabilization) was associated with fever, while virB (encoding a major transcriptional activator) was associated with low height-for-age z-score. In addition, these VRGs were associated with increased fecal MPO, and coinfection with Salmonella spp. was associated with increased abdominal pain. These data reinforce the impact of Shigella/EIEC on diarrhea in children from Brazilian semiarid region and highlighted the contributions of specific virulence genes for its pathobiology.

Background Enteroaggregative Escherichia coli (EAEC) is an important pathogen causing enteric infections worldwide. This pathotype is linked to malnutrition in children from developing countries. Alanyl-glutamine (Ala-Gln) is an immune modulator nutrient that acts during intestinal damage and/or inflammation. This study investigated the effect of EAEC infection and Ala-Gln on cell viability, cell death, and inflammation of intestinal epithelium cells (IEC-6). Methods Cells were infected with an EAEC prototype 042 strain, an EAEC wild-type strain isolated from a Brazilian malnourished child, and a commensal E coli HS. Gene transcription and protein levels of caspases-3, -8, and -9 and cytokine-induced neutrophil chemoattractant 1 (CINC-1/CXCL1) were evaluated using RT-qPCR, western blot analysis, and ELISA. Results Infections with both EAEC strains decreased cell viability and induced apoptosis and necrosis after 24 hours. Ala-Gln supplementation increased cell proliferation and reduced cell death in infected cells. Likewise, EAEC strain 042 significantly increased the transcript levels of caspases-3, -8, and -9 when compared to the control group, and Ala-Gln treatment reversed this effect. Furthermore, EAEC induced CXCL1 protein levels, which were also reduced by Ala-Gln supplementation. Conclusion These findings suggest that EAEC infection promotes apoptosis, necrosis, and intestinal inflammation with involvement of caspases. Supplementation of Ala-Gln inhibits cell death, increases cell proliferation, attenuates mediators associated with cell death, and inflammatory pathways in infected cells.

Vigorous exercise can induce gastrointestinal disorders such decreased gastric emptying pace, while low-intensity exercise can accelerate gastric motility. However, the mechanisms of these effects are still unknown. We investigated the possible neurohumoral mechanisms involved in these phenomena. In sedentary (Sed) and acute exercise (Ex) groups of rats, we assessed the activation of c-Fos in NTS and DVMN and the plasma levels of CCK and OXT. Separate groups received pretreatment with the oxytocin antagonist atosiban (AT), the cholecystokinin antagonist devazepide (DVZ), or the TRPV1 receptor inhibitor capsazepine (CAPZ). AT, DVZ and CAPZ treatments prevented (p

Aim The aim of the present study was to investigate the anti-inflammatory response mediated of the M1 muscarinic acetylcholine receptor (mAChR) during experimental colitis. Material and methods After the induction of 6% acetic acid colitis, mice were treated with McN-A-343 0.5, 1.0, and 1.5 mg/kg or dexamethasone (DEXA, 2.0 mg/kg) or pirenzepine (PIR, 10 mg/kg; M1 mAChR antagonist). Colonic inflammation was assessed by macroscopic and microscopic lesion scores, colonic wet weight, myeloperoxidase (MPO) activity, interleukin-1 beta (IL1-β) levels and tumor necrosis factor alpha (TNF-α), glutathione (GSH), malondialdehyde (MDA) and nitrate and nitrite (NO3/NO2), mRNA expression of IKKα, nuclear factor kappa beta (NF-kB) and cyclooxygenase-2 (COX-2), as well protein expression of NF-kB and COX-2. Results Treatment with McN-A-343 at a concentration of 1.5 mg/kg showed a significant reduction in intestinal damage as well as a decrease in wet weight, MPO activity, pro-inflammatory cytokine concentration, markers of oxidative stress and expression of inflammatory mediators. The action of the M1 agonist by the administration of pirenzepine, which promoted the blocking of the mAChR M1-mediated anti-inflammatory response, has also been proven. Conclusion The results suggest that peripheral colonic M1 mAChR is involved in reversing the pro-inflammatory effect of experimentally induced colitis, which may represent a promising therapeutic alternative for patients with ulcerative colitis.

Introdução: Vários fármacos têm sido avaliados para o tratamento da COVID-19, mas somente o antiviral remdesivir foi registrado nos órgãos regulatórios dos principais países desenvolvidos para esse fim. TDF e FTC demonstraram atividade contra o SARS-CoV-2 in vitro. Objetivos: Avaliar a eficácia e toxicidade de TDF e TDF/FTC em pacientes com infecção leve a moderada por COVID-19. Secundariamente, avaliamos biomarcadores de citocinas, quimiocinas e fatores de crescimento celular, associados à fisiopatogenia da COVID-19. Métodos: Ensaio clínico randomizado, duplo-cego, controlado por placebo, em pacientes com suspeita clínica de infecção respiratória leve a moderada por SARS-CoV-2. O estudo foi aprovado pela CONEP e registrado no ClinicalTrials.gov. Pacientes foram aleatoriamente recrutados para tomarem TDF (300 mg/dia) ou TDF/FTC (300/200 mg/dia) ou placebo (Vit. C - 500 mg/dia), por 10 dias. O parâmetro primário foi o escore de sintomas e sinais preditivos de COVID-19, avaliado no sétimo dia de acompanhamento dos pacientes. Resultados: 309 pacientes foram recrutados e 226 foram randomizados nos seguintes grupos: (a) 74 no grupo TDF; (b) 74 no grupo TDF/FTC; e (c) 77 no grupo placebo. Dos 226 pacientes, 139 (62%) foram positivos para o teste RT-PCR para SARS-CoV-2. Febre (≥ 37,8°C), ageusia ou disgeusia, anosmia ou disosmia e dois ou mais sintomas ou sinais clínicos foram significativamente associados com a infecção por SARS-CoV-2. Não houve alteração significativa no escore clínico baseado nos sintomas e sinais clínicos entre os grupos de tratamento. Também não houve diferença quanto aos eventos adversos e eventos adversos graves entre os grupos de tratamentos. Nenhum paciente faleceu durante o período total de 28 dias de acompanhamento do protocolo no estudo. Nos parâmetros secundários, pacientes com infecções respiratórias leve a moderadas por SARS-CoV-2 apresentaram maiores concentrações do fator de crescimento celular e citocinas pró-inflamatórias (G-CSF, IL-1β, IL-6 e TNF-α) em relação aos pacientes sem infecção por SARS-CoV-2. Conclusões: Febre (≥37,8°C), perda de olfato, perda de paladar e dois ou mais sintomas, têm maior predição para o diagnóstico de COVID-19 leve a moderada. A intervenção farmacológica com TDF ou TDF/FTC não alterou o escore de sintomas e sinais clínicos na infeção respiratória leve a moderada em pacientes com SARS-CoV-2 comparados ao grupo placebo.

Campylobacter spp. have been associated with anthropometric Z-score decrements, but the role of specific virulence genes associated with these outcomes has not been explored. This study aimed to investigate whether specific Campylobacter jejuni virulence-related gene and immune-inflammatory biomarkers are associated with malnutrition in children from Northeastern Brazil. A case-control study was performed in Fortaleza, Brazil. Children aging 6-24 months were characterized as malnourished (cases) if weight-for-age Z-score (WAZ) = 2 and as nourished (controls) if WAZ ≥ 1. DNA samples were extracted from stools and screened for C. jejuni/coli by real-time PCR. A subsequent C. jejuni-specific PCR was employed and positive samples were evaluated for 18 C. jejuni virulence genes by using four multiplex PCRs. C. jejuni was detected in 9.71% (33/340) of the children's samples, being 63.63% (21/33) from nourished and 37.37% (12/33) from malnourished children. The cadF, iamA, cheW, and sodB genes were the most frequent genes (100%, 90.9%, 87.9%, and 75.8%, respectively), while some others (ceuE, jlpA, pldA, and pVir) showed low rates (all below 6%). Malnourished children were significantly associated with infection with C. jejuni strains lacking cdtB gene (active subunit of cytolethal distending toxin) and harboring flgE gene (flagellar hook protein). These strains were also associated with children presenting increased serum SAA and sCD-14, but decreased IgG anti-LPS. These data reinforce the impact of Campylobacter jejuni infection on children without diarrhea and highlight the contribution of a specific virulence gene profile, cdtB(-)flgE(+) and increased systemic response in malnutrition children.

New Findings What is the central question of this study? Acute acidosis that results from short-term exercise is involved in delayed gastric emptying in rats and the lower responsiveness of gastric fundus strips to carbachol. Does extracellular acidosis decrease responsiveness to carbachol in tissues of sedentary rats? How? What is the main finding and its importance? Extracellular acidosis inhibits cholinergic signalling in the rat gastric fundus by selectively influencing the Gq/11 protein signalling pathway. Acute acidosis that results from short-term exercise delays gastric emptying in rats and decreases the responsiveness to carbachol in gastric fundus strips. The regulation of cytosolic Ca2+ concentrations appears to be a mechanism of action of acidosis. The present study investigated the way in which acidosis interferes with gastric smooth muscle contractions. Rat gastric fundus isolated strips at pH 6.0 presented a lower magnitude of carbachol-induced contractions compared with preparations at pH 7.4. This lower magnitude was absent in carbachol-stimulated duodenum and KCl-stimulated gastric fundus strips. In Ca2+-free conditions, repeated contractions that were induced by carbachol progressively decreased, with no influence of extracellular pH. In fundus strips, CaCl2-induced contractions were lower at pH 6.0 than at pH 7.4 but only when stimulated in the combined presence of carbachol and verapamil. In contrast, verapamil-sensitive contractions that were induced by CaCl2 in the presence of KCl did not change with pH acidification. In Ca2+ store-depleted preparations that were treated with thapsigargin, the contractions that were induced by extracellular Ca2+ restoration were smaller at pH 6.0 than at pH 7.4, but relaxation that was induced by SKF-96365 (an inhibitor of store-operated Ca2+ entry) was unaltered by extracellular acidification. At pH 6.0, the phospholipase C inhibitor U-73122 relaxed carbachol-induced contractions less than at pH 7.4, and this phenomenon was absent in tissue that was treated with the RhoA kinase blocker Y-27632. Thus, extracellular acidosis inhibited pharmacomechanical coupling in gastric fundus by selectively inhibiting the Gq/11 protein signalling pathway, whereas electromechanical coupling remained functionally preserved.

Objective Justicia pectoralis is a plant useful for the treatment of respiratory diseases. Here, we studied the antiasthmatic properties of a standardized extract of J. pectoralis (Jp). Methods Ovalbumin (OVA)-sensitized rats were actively challenged with saline or OVA to study airway hyper-responsiveness after oral treatment with saline or Jp. The ability of Jp to inhibit hyper-reactivity was evaluated in isolated trachea mounted in isolated organ bath chamber. Key findings Using KCl or carbachol as contractile agents, tracheal rings of OVA-challenged rats contracted with higher magnitude than trachea of rats challenged with saline. Such hyper-responsive phenotype of OVA-challenged tissues decreased with Jp administration. In Ca+-free medium, Jp or its major constituent coumarin inhibited preferentially the contractions induced by Ca2+ addition in tissues of OVA-challenged rats stimulated with KCl or acetylcholine. In tissues depleted of their internal Ca+ stores in the presence of thapsigargin, Jp inhibited the contraction induced by capacitative Ca2+ entry. By gavage, Jp abolished the increase caused by challenge with OVA on the levels of IL-1β and TNF-α in the bronchoalveolar fluid and also impaired the changes in gene expression of canonical transient receptor proteins. Conclusions Jp has antiasthmatic properties in an experimental model that reproduces tracheal hyper-reactivity.

Background Rotavirus A (RVA) is one of the leading causes of acute gastroenteritis worldwide; however, few studies assessed RVA genetics with community surveillance. Objectives This study aimed to investigate clinical data, genetic diversity, and coinfection patterns of RVA infections in children from 2 to 36 months old with or without community childhood diarrhea in the Brazilian semiarid region during postvaccination era. Methods We enrolled and collected socioeconomic/clinical information using a standardized questionnaire and fecal samples from 291 children. Viral RNA samples were extracted and analyzed using quantitative reverse transcription polymerase chain reaction to establish the diagnosis of RVA. Sequencing of VP7 and VP4 (VP8*) regions and phylogenetic analysis were performed. Results RVA-negative diagnosis was associated with children 24 to 36 months old with complete vaccination schedule. Genotype G1P[8] was the most prevalent (57%), whereas unusual genotypes including G1P[4], G2P[8], and G3P[9] were also detected. G1- and P[8]-positive samples showed high degrees of similarity with the vaccine strain. RVA coinfections were frequently observed, and enteroaggregative Escherichia coli was the most prevalent copathogen. Conclusions These results demonstrate that genotype G1P[8] is the most prevalent strain. VP7 and/or VP8* gene segments arising from RV1 vaccine strain were documented in these children, suggesting shedding or herd vaccination. Moreover, our study indicates full vaccination is important for protection against RVA infections.

Summary Cardiovascular diseases are among the main causes of mortality worldwide, and dyslipidemia is a principal factor risk. Hence the study of biochemical markers is necessary for early diagnosis. Objectives Evaluate biomarkers to diagnose the risks of cardiovascular diseases in healthy Brazilian and African young adults. Design & Methods Weight, height, waist circumference, percentage of body fat and systemic blood pressure were measured; and fasting blood samples were taken for biochemical analysis. Triglycerides, total cholesterol, HDL-c, and apolipoproteins A-I and B were measured on automated equipment using commercially available kits, in addition to the tests of antioxidant capacity of HDL and the enzymatic activity of Paraoxonase 1. Results After statistical analysis, it was found that BMI, WC, fat (%), triglycerides, ApoB/ApoA-I ratio and Vmax were higher in Brazilians, while HDL-c, ApoA-I, Lag Time, Vmax and PON1 activity were higher in Africans. In Brazilians, the ApoB/ApoA-I ratio was related to obesity factors and lipid profile, but in Africans it was related only to lipids. The antioxidant capacity of HDL and PON1 activity was better in Africans. Through independence testing, we observed an association with moderate risk of myocardial infarction with gender in Africans. In the binary logistic regression analysis, it was found that men in general – and particularly African men – have higher risk of myocardial infarction than women; Odds Ratio 2144 (CI95%: 1343–3424) and 2281 (CI95%: 1082–4811), respectively. Conclusions The anthropometric and biochemical parameters of Brazilians, especially men, predispose them to greater risks of cardiovascular diseases.

Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrhea in children from developing countries and presents high genetic variability. We aimed to characterize the EPEC virulence-related gene (VRG) distribution and copathogens associated with diarrhea and nutrition-related outcomes in children from the low-income Brazilian semiarid region. A cross-sectional case-control study of diarrhea was conducted in 1,191 children aged 2 to 36 months from the northeast region of Brazil. Stool samples were collected and clinical, epidemiological, and anthropometric data were identified from each child. A broad molecular evaluation of enteropathogens was performed, and EPEC-positive samples were further investigated for 18 VRGs using five multiplex PCRs. EPEC was detected in 28.2% of the study population, with similar proportions among cases and controls. Typical EPEC (tEPEC) infections were more often associated with diarrhea than atypical EPEC (aEPEC) infections, while aEPEC infections presented a higher prevalence. The VRG ler, a negative regulator of the locus of enterocyte effacement, was associated with the absence of diarrhea in aEPEC-positive children; espB, a major component of the type 3 secretion system, was associated with diarrhea in tEPEC-positive children; the presence of procolonization VRGs—the combination of cesT positivity, espP negativity, and the presence of the map gene—was associated with undernutrition; and Campylobacter spp., norovirus, and enteroaggregative E. coli (EAEC) coinfections were associated with increased clinical severity in EPEC-infected children. These data identified tEPEC strains associated with diarrhea and specific VRGs of EPEC (ler, espB, cesT, and map genes) and Campylobacter spp., norovirus, and EAEC to be major contributors to diarrhea and undernutrition in children from a low-income Brazilian region.

Made available in DSpace on 2019-10-04T12:33:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2019-10-09T18:33:45Z : No. of bitstreams: 1 S0100-879X2019000100608.pdf: 1777134 bytes, checksum: c4fdd0be10e8456a9b1e3b6cdde7a919 (MD5) Bredemeyera floribunda roots are popularly used to treat snakebites in the semiarid region of Northeast Brazil, and previous studies indicate the anti-ophidian actions of triterpenoid saponins found in its roots. To assess B. floribunda root extract (BFRE) activity against the effects of Bothrops jararacussu venom (BjuV), antiphospholipasic, antiproteolytic, antihemorrhagic, antinecrotic, and anti-edematogenic activities were investigated in mice. Phytochemical analysis revealed the presence of saponins, flavonoids, and sugars, with rutin and saccharose being the major constituents of BFRE. Acute toxicity was determined and BFRE was nontoxic to mice. Phospholipase A2 and proteolytic activities induced by BjuV were inhibited in vitro by BFRE at all concentrations tested herein. BFRE (150 mg/kg) inhibited paw edema induced by BjuV (50 mu g/animal), reducing total edema calculated by area under the curve, but carrageenan-induced paw edema was unchanged. Hemorrhagic and necrotizing actions of BjuV (50 mu g/animal) were considerably decreased by BFRE treatment. Thus, BFRE blocked the toxic actions of B. jararacussu venom despite having no anti-inflammatory activity, which points to a direct inhibition of venom's toxins, as demonstrated in the in vitro assays. The larger amounts of rutin found in BFRE may play a role in this inhibition, since 3',4'-OH flavonoids are known inhibitors of phospholipases A2. Univ Fed Ceara, Dept Fisiol & Farmacol, Fortaleza, Ceara, Brazil Univ Fed Pernambuco, Dept Antibiot, Recife, PE, Brazil Univ Fed Pernambuco, Ctr Acad Vitoria, Vitoria De Santo Antao, PE, Brazil Univ Estadual Ceara, Fac Vet, Fortaleza, Ceara, Brazil Univ Paulista, Campus Jundiai, Jundiai, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Sao Vicente, SP, Brazil Univ Fed Rio Grande do Norte, Inst Quim, Natal, RN, Brazil Univ Fed Ceara, Dept Anal Clin & Toxicol, Fortaleza, Ceara, Brazil Univ Estadual Paulista, Inst Biociencias, Sao Vicente, SP, Brazil

Objective Vitamin A is commonly recommended as a treatment for diarrhea and undernutrition; however, little is known about the underlying cellular mechanisms. The aim of this study was to investigate the modulation of cell cycle by vitamin A derivatives (retinyl palmitate or retinol) in undernourished intestinal epithelial crypts (IEC-6). Methods IEC-6 cells were exposed to nutrient deprivation (no serum and no glutamine) and supplemented with retinyl palmitate or retinol at a range of 2 to 20 μM. Proliferation, apoptosis/necrosis, cell cycle process, and gene transcription were assessed. Results Nutrient deprivation for 6, 12, 24, or 48 h decreased cell proliferation, and retinyl palmitate further decreased it after 24 and 48 h. Apoptosis rates were reduced by undernourishment and further reduced by retinyl palmitate after 48 h; whereas necrosis rates were unaltered. Undernourishment induced overall cell quiescence, increased percentage of cells in G0/G1 phase and decreased percentage of cells in S phase after 12 h and in G2/M phases at 6, 12, and 24 h after treatment. Both retinoids also showed cell quiescence induction with less cells in G2/M phases after 48 h, whereas only retinol showed significant modulation of G0/G1 and S phases. Both retinoids also increased markers of cell differentiation Fabp and Iap gene transcriptions in about fivefold rates after 42 h. Furthermore, specific gene transcriptions related to MAP kinase signaling pathway regulation of cell differentiation and cell cycle regulation were triggered by retinoids in undernourished IEC-6, with higher levels of expression for Atf2 and C-jun genes. Conclusions These findings indicated that both vitamin A derivatives induce further survival mechanisms in undernourished intestinal epithelial crypt cells. These mechanisms include increased cell quiescence, decreased apoptosis, increased cell differentiation, and transcription of genes related to MAP kinase signaling pathway.

Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrhea in children from developing countries and presents high genetic variability. We aimed to characterize the EPEC virulence-related gene (VRG) distribution and copathogens associated with diarrhea and nutrition-related outcomes in children from the low-income Brazilian semiarid region. A cross-sectional case-control study of diarrhea was conducted in 1,191 children aged 2 to 36 months from the northeast region of Brazil. Stool samples were collected and clinical, epidemiological, and anthropometric data were identified from each child. A broad molecular evaluation of enteropathogens was performed, and EPEC-positive samples were further investigated for 18 VRGs using five multiplex PCRs. EPEC was detected in 28.2% of the study population, with similar proportions among cases and controls. Typical EPEC (tEPEC) infections were more often associated with diarrhea than atypical EPEC (aEPEC) infections, while aEPEC infections presented a higher prevalence. The VRG ler, a negative regulator of the locus of enterocyte effacement, was associated with the absence of diarrhea in aEPEC-positive children; espB, a major component of the type 3 secretion system, was associated with diarrhea in tEPEC-positive children; the presence of procolonization VRGs—the combination of cesT positivity, espP negativity, and the presence of the map gene—was associated with undernutrition; and Campylobacter spp., norovirus, and enteroaggregative E. coli (EAEC) coinfections were associated with increased clinical severity in EPEC-infected children. These data identified tEPEC strains associated with diarrhea and specific VRGs of EPEC (ler, espB, cesT, and map genes) and Campylobacter spp., norovirus, and EAEC to be major contributors to diarrhea and undernutrition in children from a low-income Brazilian region.

PURPOSE OF REVIEW The current review is to update the results on epidemiology, pathobiology, and genes related to virulence, clinical presentation, molecular diagnosis, antimicrobial resistance, and extraintestinal infection of enteroaggregative Escherichia coli (EAEC). RECENT FINDINGS EAEC subclinical infection was significantly associated with reduced length at 2 years of age and EAEC and coinfections were associated with reduced delta weight-for-length and weight-for-age z-scores in the first 6 months of age in the MAL-ED birth cohort study. EAEC was associated with malnutrition in children 6-24 months of age in prospective case-control studies in Bangladesh and Brazil. Virulence gene-based studies have suggested aggregative fimbriae II may be a major contributor to disease, whereas AggR-activated regulator a marker of less severe disease. The high ability of EAEC colonization likely exacerbates effects of other microbial virulence strategies. Molecular diagnosis has been useful for understanding EAEC burden, although different criteria may relate to different pathogenic outcomes. SUMMARY EAEC gained special interest in the past few years, especially due to association with growth decrements in children with subclinical infections and its important role as a copathogen. Understanding of EAEC pathogenesis advanced but further research is needed for elucidating both microbial and host factors influencing infection outcomes.

BACKGROUND AND OBJECTIVE Norovirus (NoV) infections are known to have high-morbidity and mortality rates and are a major health problem globally. The impact of NoV on child development is, however, poorly understood. We evaluated the distribution of NoV genotypes in children from a low-income Brazilian semiarid region, in relation with their clinical symptoms, nutritional status, and co-pathogens. METHODS The test population included children aged 2 to 36 months from 6 cities of the Brazilian semiarid region. Fecal samples were collected from each child, along with the information regarding their socioeconomic/clinical conditions using a standardized questionnaire. Detection and quantification of NoV were performed by reverse-transcription quantitative polymerase chain reaction, followed by molecular and phylogenetic analyses. RESULTS The NoV detection rate was 45.2%. Presence of NoV was associated with lower z scores for weight-for-age (P = 0.03), weight-for-height (P = 0.03), and body mass index-for-age (P = 0.03). NoV infection was associated with more frequent respiratory illnesses (P

Summary Background Enteropathogen infections in early childhood not only cause diarrhoea but contribute to poor growth. We used molecular diagnostics to assess whether particular enteropathogens were associated with linear growth across seven low-resource settings. Methods We used quantitative PCR to detect 29 enteropathogens in diarrhoeal and non-diarrhoeal stools collected from children in the first 2 years of life obtained during the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) multisite cohort study. Length was measured monthly. We estimated associations between aetiology-specific diarrhoea and subclinical enteropathogen infection and quantity and attained length in 3 month intervals, at age 2 and 5 years, and used a longitudinal model to account for temporality and time-dependent confounding. Findings Among 1469 children who completed 2 year follow-up, 35 622 stool samples were tested and yielded valid results. Diarrhoeal episodes attributed to bacteria and parasites, but not viruses, were associated with small decreases in length after 3 months and at age 2 years. Substantial decrements in length at 2 years were associated with subclinical, non-diarrhoeal, infection with Shigella (length-for-age Z score [LAZ] reduction −0·14, 95% CI −0·27 to −0·01), enteroaggregative Escherichia coli (−0·21, −0·37 to −0·05), Campylobacter (−0·17, −0·32 to −0·01), and Giardia (−0·17, −0·30 to −0·05). Norovirus, Cryptosporidium, typical enteropathogenic E coli, and Enterocytozoon bieneusi were also associated with small decrements in LAZ. Shigella and E bieneusi were associated with the largest decreases in LAZ per log increase in quantity per g of stool (−0·13 LAZ, 95% CI −0·22 to −0·03 for Shigella; −0·14, −0·26 to −0·02 for E bieneusi). Based on these models, interventions that successfully decrease exposure to Shigella, enteroaggregative E coli, Campylobacter, and Giardia could increase mean length of children by 0·12–0·37 LAZ (0·4–1·2 cm) at the MAL-ED sites. Interpretation Subclinical infection and quantity of pathogens, particularly Shigella, enteroaggregative E coli, Campylobacter, and Giardia, had a substantial negative association with linear growth, which was sustained during the first 2 years of life, and in some cases, to 5 years. Successfully reducing exposure to certain pathogens might reduce global stunting. Funding Bill & Melinda Gates Foundation.

Optimum management of childhood diarrhoea in low-resource settings has been hampered by insufficient data on aetiology, burden, and associated clinical characteristics. We used quantitative diagnostic methods to reassess and refine estimates of diarrhoea aetiology from the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study.We re-analysed stool specimens from the multisite MAL-ED cohort study of children aged 0-2 years done at eight locations (Dhaka, Bangladesh; Vellore, India; Bhaktapur, Nepal; Naushero Feroze, Pakistan; Venda, South Africa; Haydom, Tanzania; Fortaleza, Brazil; and Loreto, Peru), which included active surveillance for diarrhoea and routine non-diarrhoeal stool collection. We used quantitative PCR to test for 29 enteropathogens, calculated population-level pathogen-specific attributable burdens, derived stringent quantitative cutoffs to identify aetiology for individual episodes, and created aetiology prediction scores using clinical characteristics.We analysed 6625 diarrhoeal and 30 968 non-diarrhoeal surveillance stools from 1715 children. Overall, 64·9% of diarrhoea episodes (95% CI 62·6-71·2) could be attributed to an aetiology by quantitative PCR compared with 32·8% (30·8-38·7) using the original study microbiology. Viral diarrhoea (36·4% of overall incidence, 95% CI 33·6-39·5) was more common than bacterial (25·0%, 23·4-28·4) and parasitic diarrhoea (3·5%, 3·0-5·2). Ten pathogens accounted for 95·7% of attributable diarrhoea: Shigella (26·1 attributable episodes per 100 child-years, 95% CI 23·8-29·9), sapovirus (22·8, 18·9-27·5), rotavirus (20·7, 18·8-23·0), adenovirus 40/41 (19·0, 16·8-23·0), enterotoxigenic Escherichia coli (18·8, 16·5-23·8), norovirus (15·4, 13·5-20·1), astrovirus (15·0, 12·0-19·5), Campylobacter jejuni or C coli (12·1, 8·5-17·2), Cryptosporidium (5·8, 4·3-8·3), and typical enteropathogenic E coli (5·4, 2·8-9·3). 86·2% of the attributable incidence for Shigella was non-dysenteric. A prediction score for shigellosis was more accurate (sensitivity 50·4% [95% CI 46·7-54·1], specificity 84·0% [83·0-84·9]) than current guidelines, which recommend treatment only of bloody diarrhoea to cover Shigella (sensitivity 14·5% [95% CI 12·1-17·3], specificity 96·5% [96·0-97·0]).Quantitative molecular diagnostics improved estimates of pathogen-specific burdens of childhood diarrhoea in the community setting. Viral causes predominated, including a substantial burden of sapovirus; however, Shigella had the highest overall burden with a high incidence in the second year of life. These data could improve the management of diarrhoea in these low-resource settings.BillMelinda Gates Foundation.

We evaluated the impact of subclinical enteroaggregative Escherichia coli (EAEC) infection alone and in combination with other pathogens in the first 6 months of life on child growth.Nondiarrheal samples from 1684 children across 8 Multisite Birth Cohort Study, Malnutrition and Enteric Diseases (MAL-ED) sites in Asia, Africa, and Latin America were tested monthly; more than 90% of children were followed-up twice weekly for the first 6 months of life.Children with subclinical EAEC infection did not show altered growth between enrollment and 6 months. Conversely, EAEC coinfection with any other pathogen was negatively associated with delta weight-for-length (P 0.05) and weight-for-age (P 0.05) z scores between 0 and 6 months. The presence of 2 or more pathogens without EAEC was not significantly associated with delta weight-for-length and weight-for-age. The most frequent EAEC coinfections included Campylobacter spp, heat-labile toxin-producing enterotoxigenic E coli, Cryptosporidium spp, and atypical enteropathogenic E coli. Myeloperoxidase levels were increased with EAEC coinfection (P 0.05). EAEC pathogen codetection was associated with lower neopterin levels compared to those of no-pathogen control children (P 0.05). Mothers of children with EAEC coinfections had lower levels of education, poorer hygiene and sanitation, lower socioeconomic status, and lower breast-feeding rates compared to mothers of children in whom no pathogen was detected (P 0.05).These data emphasize the public health importance of subclinical EAEC infection in early infancy in association with other pathogens and the need for improved maternal and child care, hygiene, sanitation, and socioeconomic factors.

Mycobacterium leprae bacilli are mainly transmitted by the dissemination of nasal aerosols from multibacillary (MB) patients to susceptible individuals through inhalation. The upper respiratory tract represents the main entry and exit routes of M. leprae. Therefore, this study aimed to evaluate the sensitivity and specificity of real-time quantitative polymerase chain reaction (qPCR) in detecting M. leprae in nasal secretion (NS) and skin biopsy (SB) samples from MB and paucibacillary (PB) cases. Fifty-four NS samples were obtained from leprosy patients at the Dona Libânia National Reference Centre for Sanitary Dermatology in Ceará, Brazil. Among them, 19 MB cases provided both NS and SB samples. Bacilloscopy index assays were conducted and qPCR amplification was performed using specific primers for M. leprae 16S rRNA gene, generating a 124-bp fragment. Primer specificity was verified by determining the amplicon melting temperature (T(m) = 79.5 °C) and detection limit of qPCR was 20 fg of M. leprae DNA. Results were positive for 89.7 and 73.3% of NS samples from MB and PB cases, respectively. SB samples from MB patients were 100% positive. The number of bacilli detected in NS samples were 1.39 × 10(3)–8.02 × 10(5), and in SB samples from MB patients were 1.87 × 10(3)–1.50 × 10(6). Therefore, qPCR assays using SYBR Green targeting M. leprae 16S rRNA region can be employed in detecting M. leprae in nasal swabs from leprosy patients, validating this method for epidemiological studies aiming to identify healthy carriers among household contacts or within populations of an endemic area.

Purpose of review Shigella spp. are important etiologic agents of diarrhea worldwide. This review summarizes the recent findings on the epidemiology, diagnosis, virulence genes, and pathobiology of Shigella infection. Recent findings Shigella flexneri and Shigella sonnei have been identified as the main serogroups circulating in developing and developed countries, respectively. However, a shift in the dominant species from S. flexneri to S. sonnei has been observed in countries that have experienced recent improvements in socioeconomic conditions. Despite the increasing usage of molecular methods in the diagnosis and virulence characterization of Shigella strains, researchers have been unsuccessful in finding a specific target gene for this bacillus. New research has demonstrated the role of proteins whose expressions are temperature-regulated, as well as genes involved in the processes of adhesion, invasion, dissemination, and inflammation, aiding in the clarification of the complex pathobiology of shigellosis. Summary Knowledge about the epidemiologic profile of circulating serogroups of Shigella and an understanding of its pathobiology as well as of the virulence genes is important for the development of preventive measures and interventions to reduce the worldwide spread of shigellosis.

What is the central question of this study? Acute acidosis that results from short-term exercise is involved in delayed gastric emptying in rats and the lower responsiveness of gastric fundus strips to carbachol. Does extracellular acidosis decrease responsiveness to carbachol in tissues of sedentary rats? How? What is the main finding and its importance? Extracellular acidosis inhibits cholinergic signalling in the rat gastric fundus by selectively influencing the G

Molecular characterization of virulence and antimicrobial resistance profiles were determined for Shigella species isolated from children with diarrhea in Fortaleza, Brazil. Fecal specimens were collected along with socioeconomic and clinical data from children with moderate to severe diarrhea requiring emergency care. Shigella spp. were isolated by standard microbiological techniques, and we developed 4 multiplex polymerase chain reaction assays to detect 16 virulence-related genes (VRGs). Antimicrobial susceptibility tests were performed using disk diffusion assays. S. flexneri and S. sonnei were the predominant serogroups. S. flexneri was associated with low monthly incomes; more severe disease; higher number of VRGs; and presence of pic, set, and sepA genes. The SepA gene was associated with more intense abdominal pain. S. flexneri was correlated with resistance to ampicillin and chloramphenicol, whereas S. sonnei was associated with resistance to azithromycin. Strains harboring higher numbers of VRGs were associated with resistance to more antimicrobials. We highlight the correlation between presence of S. flexneri and sepA, and increased virulence and suggest a link to socioeconomic change in northeastern Brazil. Additionally, antimicrobial resistance was associated with serogroup specificity in Shigella spp. and increased bacterial VRGs.

The impact of enteroaggregative E. coli (EAEC) infection on childhood malnutrition and inflammation has been suggested, regardless of diarrhea. We investigated whether EAEC and its virulence-related genes (VRGs) are associated with malnutrition in a case–control study. Children aged 6–24 months from Brazil were enrolled as malnourished if weight-for-age Z-score (WAZ) ≤ −2 and nourished if WAZ > −1. Stools were cultured and examined for E. coli. DNA was extracted from fecal isolates and tested for EAEC by polymerase chain reaction (PCR). Positive samples were analyzed by 5 multiplex PCRs to identify 20 EAEC VRGs. Biomarkers of intestinal barrier function and inflammation were measured. The prevalence of EAEC was 39.94%. Samples that presented both aaiC and aatA genes were associated with malnutrition (P = 0.045). A high prevalence of VRGs was observed and the aafC gene was significantly associated with malnourished (P = 0.0101). Strains lacking aar and pic genes were associated with malnutrition (P = 0.018), while the concomitant presence of aar, pic, agg4A, and capU genes was associated with nourished (P = 0.031). These data reinforce the EAEC impact on malnutrition, the importance of aar as negative regulator and the great contribution of AAF/II fimbria for the pathobiology of EAEC.

Malnutrition results in serious consequences for growth and cognitive development in children. We studied select child and maternal biologic factors, socioeconomic factors, enteric pathogenic burden and gut function biomarkers in 402 children 6-24 months of age in Northeastern Brazil. In this prospective case-control study, not being fed colostrum [odds ratio (OR): 3.29, 95% confidence interval (CI): 1.73-6.26], maternal age ≥18 years (OR: 1.88, 95% CI: 1.10-3.22) and no electric fan (OR: 2.46, 95% CI: 1.22-4.96) or bicycle (OR: 1.80, 95% CI: 1.10-2.95) in the household were positively associated, and higher birth weight (OR: 0.27, 95% CI: 0.19-0.38), larger head circumference (OR: 0.74, 95% CI: 0.66-0.82) and shortness of breath in the last 2 weeks (OR: 0.49, 95% CI: 0.27-0.90) were negatively associated with malnutrition. Subclinical enteric pathogen infections were common, and enteroaggregative Escherichia coli infections were more prevalent in malnourished children (P = 0.045). Biomarkers such as the lactulose-mannitol test, myeloperoxidase, neopterin and calprotectin were highly elevated in both malnourished and nourished children. Nourished children had a better systemic immune response than the malnourished children, as detected by elevated serum amyloid A-1 and soluble cluster of differentiation protein 14 biomarkers (P < 0.001). Serum amyloid A-1 and soluble cluster of differentiation protein 14 were also associated with better nutritional Z scores. Neonatal, maternal and socioeconomic factors were associated with malnutrition in children. There was a substantial subclinical enteric pathogen burden, particularly with enteroaggregative E. coli, in malnourished children.

Despite its population, geographic size, and emerging economic importance, disproportionately little genome-scale research exists into genetic factors that predispose Brazilians to disease, or the population genetics of risk. After identification of suitable proxy populations and careful analysis of tri-continental admixture in 1,538 North-Eastern Brazilians to estimate individual ancestry and ancestral allele frequencies, we computed 400,000 genome-wide locus-specific branch length (LSBL) Fst statistics of Brazilian Amerindian ancestry compared to European and African; and a similar set of differentiation statistics for their Amerindian component compared with the closest Asian 1000 Genomes population (surprisingly, Bengalis in Bangladesh). After ranking SNPs by these statistics, we identified the top 10 highly differentiated SNPs in five genome regions in the LSBL tests of Brazilian Amerindian ancestry compared to European and African; and the top 10 SNPs in eight regions comparing their Amerindian component to the closest Asian 1000 Genomes population. We found SNPs within or proximal to the genes CIITA (rs6498115), SMC6 (rs1834619), and KLHL29 (rs2288697) were most differentiated in the Amerindian-specific branch, while SNPs in the genes ADAMTS9 (rs7631391), DOCK2 (rs77594147), SLC28A1 (rs28649017), ARHGAP5 (rs7151991), and CIITA (rs45601437) were most highly differentiated in the Asian comparison. These genes are known to influence immune function, metabolic and anthropometry traits, and embryonic development. These analyses have identified candidate genes for selection within Amerindian ancestry, and by comparison of the two analyses, those for which the differentiation may have arisen during the migration from Asia to the Americas.

Mycobacterium leprae bacilli are mainly transmitted by the dissemination of nasal aerosols from multibacillary (MB) patients to susceptible individuals through inhalation. The upper respiratory tract represents the main entry and exit routes of M. leprae. Therefore, this study aimed to evaluate the sensitivity and specificity of real-time quantitative polymerase chain reaction (qPCR) in detecting M. leprae in nasal secretion (NS) and skin biopsy (SB) samples from MB and paucibacillary (PB) cases. Fifty-four NS samples were obtained from leprosy patients at the Dona Libânia National Reference Centre for Sanitary Dermatology in Ceará, Brazil. Among them, 19 MB cases provided both NS and SB samples. Bacilloscopy index assays were conducted and qPCR amplification was performed using specific primers for M. leprae 16S rRNA gene, generating a 124-bp fragment. Primer specificity was verified by determining the amplicon melting temperature (Tm = 79.5 °C) and detection limit of qPCR was 20 fg of M. leprae DNA. Results were positive for 89.7 and 73.3% of NS samples from MB and PB cases, respectively. SB samples from MB patients were 100% positive. The number of bacilli detected in NS samples were 1.39 × 103–8.02 × 105, and in SB samples from MB patients were 1.87 × 103–1.50 × 106. Therefore, qPCR assays using SYBR Green targeting M. leprae 16S rRNA region can be employed in detecting M. leprae in nasal swabs from leprosy patients, validating this method for epidemiological studies aiming to identify healthy carriers among household contacts or within populations of an endemic area.

The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort in the study's Fortaleza, Brazil, catchment area has a population of approximately 82 300 inhabitants. Most of the households (87%) have access to clean water, 98% have electricity, and 69% have access to improved toilet/sanitation. Most childbirths occur at the hospital, and the under-5 mortality rate is 20 per 1000 live births. The MAL-ED case-control study population, identified through the Institute for the Promotion of Nutrition and Human Development (IPREDE), serves 600 000 inhabitants from areas totaling about 42% of the city of Fortaleza. IPREDE receives referrals from throughout the state of Ceará for infant nutrition, and provides services including teaching activities and the training of graduate students and health professionals, while supporting research projects on child nutrition and health. In this article, we describe the geographic, demographic, socioeconomic, anthropometric, and environmental status of the MAL-ED cohort and case-control study populations in Fortaleza, Brazil.

Describing the early life associations between infectious disease episodes and growth, cognitive development, and vaccine response in the first 2 years of life is one of the primary goals of the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study. To collect high-resolution data during a critical early period of development, field staff visit each study participant at their house twice weekly from birth to 2 years of age to collect daily reported illness and treatment data from caregivers. Detailed infectious disease histories will not only allow us to relate the overall burden of infectious disease with the primary outcomes of the study, but will also allow us to describe the ages at which infectious diseases have the greatest effect on child health. In addition, twice-weekly visits allow for sample collection when diarrhea episodes are identified. This article describes the methods used to collect illness and treatment history data and discusses the a priori definitions of diarrhea and acute lower respiratory illness episodes.

The overall goal of The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study is to evaluate the roles of repeated enteric infection and poor dietary intakes on the development of malnutrition, poor cognitive development, and diminished immune response. The use of 8 distinct sites for data collection from Latin America, sub-Saharan Africa, and South Asia allow for an examination of these relationships across different environmental contexts. Key to testing study hypotheses is the collection of appropriate data to characterize the dietary intakes and nutritional status of study children from birth through 24 months of age. The focus of the current article is on the collection of data to describe the nature and adequacy of infant feeding, energy and nutrient intakes, and the chosen indicators to capture micronutrient status in children over time.

Temporomandibular joint (TMJ) arthritis is a common cause of orofacial pain. In the present study, the modulatory effects of N-methyl-d-aspartate receptors (NMDA-Rs) and magnesium were investigated in TMJ arthritis hypernociception. Male Wistar rats received an intra-articular injection of carrageenan (Cg) in the TMJ, and mechanical hypernociception was measured. The NMDA-R antagonist, MK-801, and magnesium chloride (MgCl₂ ) were administered before arthritis induction. Magnesium deficiency was promoted by feeding rats a synthetic magnesium-free diet for 9 d before injection of Cg. The Cg induced mechanical hypernociception that lasted for 120 h. MK-801 inhibited this hypernociceptive state. MgCl₂ pretreatment prevented Cg-induced hypernociception and altered the nociceptive threshold in the absence of Cg. Magnesium deficiency increased hypernociception and induced spontaneous hypernociceptive behavior. TMJ arthritis increased the expression of mRNA for all NMDA-R subunits and immunostaining of phosphorylated NR1 (phospho-NR1). MgCl₂ inhibited expression of NR2B mRNA and phospho-NR1 immunostaining and increased expression of NR3 mRNA. Magnesium deficiency increased expression of both NR1 and NR3 mRNAs and phospho-NR1 immunostaining in the trigeminal subnucleus caudalis. We found that magnesium modulates nociceptive behavior and induces NMDA-R subunit rearrangement in the subnucleus caudalis. The present results may lead to a better understanding of central processing in the nociceptive trigeminal pathway and the development of new approaches to treat orofacial pain with a TMJ origin.

Arthropod venoms are potential sources of neuroactive substances, providing new tools for the design of drugs. The aim of this study was to evaluate the effects of Dinoponera quadriceps venom (DqV) on seizure models in mice induced by pentylenetetrazole (PTZ), pilocarpine, and strychnine. In the PTZ model, intraperitoneal treatment with DqV (0.5 mg/kg) increased the time until the first seizure and the percentage of survival (155.4 ± 27.7 s/12.5%, p < 0.05) compared to the control group (79.75 ± 3.97 s/0%), whereas endovenous treatment (0.1 and 0.5 mg/kg) decreased the time until the first seizure (0.1 mg/kg: 77.83 ± 5.3 s versus 101.0 ± 3.3 s in the control group; 0.5 mg/kg: 74.43 ± 3.9 s versus 101.0 ± 3.3 s for the control group, p < 0.05). We did not observe significant changes in the pilocarpine- and strychnine-induced seizure models. In assays that measured oxidative parameters in the PTZ model, intraperitoneal treatment with DqV (0.5 and 2.0 mg/kg) only decreased the levels of MDA and nitrite in the cortex. However, endovenous treatment with DqV (0.1 and 0.5 mg/kg) increased the levels of MDA in the cortex and hippocampus and at a dose of 0.5 mg/kg in the striatum. Moreover, increased in nitrite content was observed in all three of the brain regions analyzed. Taken together, the D. quadriceps venom caused both neuroprotective and neurotoxic effects in a PTZ-induced seizure model, and this effect was dependent on the route of administration used.

Bites from snake (Bothrops genus) cause local tissue damage and systemic complications, which include alterations such as hemostatic system and acute renal failure (ARF). Recent studies suggest that ARF pathogenesis in snakebite envenomation is multifactorial and involves hemodynamic disturbances, immunologic reactions and direct nephrotoxicity. The aim of the work was to investigate the effects of the Bothrops leucurus venom (BlV) in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin-Darby Canine kidney). BlV (10 μg/mL) reduced the perfusion pressure at 90 and 120 min. The renal vascular resistance (RVR) decreased at 120 min of perfusion. The effect on urinary flow (UF) and glomerular filtration rate (GFR) started 30 min after BlV infusion, was transient and returned to normal at 120 min of perfusion. It was also observed a decrease on percentual tubular transport of sodium (%TNa(+)) at 120 min and of chloride (%TCl(-)) at 60 and 90 min. The treatment with BlV caused decrease in cell viability to the lowest concentration tested with an IC(50) of 1.25 μg/mL. Flow cytometry with annexin V and propidium iodide showed that cell death occurred predominantly by necrosis. However, a cell death process may involve apoptosis in lower concentrations. BlV treatment (1.25 μg/mL) led to significant depolarization of the mitochondrial membrane potential and, indeed, we found an increase in the expression of cell death genes in the lower concentrations tested. The venom also evoked an increase in the cytosolic Ca(2+) in a concentration dependent manner, indicating that Ca(2+) may participate in the venom of B. leucurus effect. The characterization of the effects in the isolated kidney and renal tubular cells gives strong evidences that the acute renal failure induced by this venom is a result of the direct nephrotoxicity which may involve the cell death mechanism.

Enteroaggregative Escherichia coli (EAEC) is a common cause of infectious diarrhea, especially in children living in poor-resource countries. In this article, we present a SYBR Green-based real-time polymerase chain reaction (qPCR) method for quantitative detection of EAEC in DNA directly extracted from human stool samples. To test the proposed qPCR system, we examined specificity, sensitivity, repeatability, and also the degree of DNA extraction efficiency using EAEC strain 042 spiked into EAEC-free stool sample. The specificity of this assay was proved using six strains of EAEC, seven strains of other E. coli types, and one strain of Shigella. The detection limit of qPCR was 67 CFU/reaction. In naturally infected stool samples, we found EAEC in quantities varying from 6.7 × 10(5) to 2 × 10(9 ) CFU/g of feces. We could not detect any reduction after stool DNA extraction for the amounts of 10(7) and 10(6) CFU/mL of spiked EAEC. This qPCR assay is simple, rapid, reproducible, sensitive, specific, and allows rapid EAEC quantification to be used in a variety of further EAEC studies. This new quantitative method provides a relatively simple means to quantify EAEC, which will likely be key to understanding the pathophysiology and impact of EAEC infection.