Chagas disease in rural areas of Chaco Province, Argentina: epidemiologic survey in humans, reservoirs, and vectors

We studied the seroprevalence of antibodies against Trypanosoma cruzi in the human population along with domiciliary infestation by triatomine bugs in an area endemic for Chagas disease in the Chaco Province of Argentina. In addition, we carried out parasitologic surveys in patients, dogs, wild mammals, and vectors. The mean seroprevalence in humans was 27.81% (109 of 392) and 24.14% (63 of 261) in 1-15-year-old children. The minimum domiciliary infestation rate was 13.33%, with certain areas reaching 53.85%. The prevalence was 15.09% (16 of 106) in dogs and 35.71% (10 of 28) in opossums. Infection with T. cruzi was detected in 30.10% (59 of 196) of the Triatoma infestans tested. Compared with nationwide studies, our data suggest that 1) there are zones requiring immediate sanitary action, and 2) nationwide estimates are based on very heterogeneous epidemiologic situations. This heterogeneity emphasizes the importance of in-depth studies of restricted areas to provide additional information for a better understanding of the present status of Chagas disease in Argentina.     

Physiological concentrations of melatonin inhibit the nitridergic pathway in the Syrian hamster retina

In the present work, the effect of melatonin on the hamster retinal nitridergic pathway was examined. When the retinas were incubated in the presence of low concentrations (1 pM-10 nM) of melatonin for 15 min, a significant decrease of nitric oxide synthase (NOS) activity was observed. However, when crude retinal homogenates were preincubated with melatonin for 15 min, no changes in NOS activity were detected, despite the fact that under the same conditions trifluoperazine, a calmodulin inhibitor, significantly decreased enzymatic activity. Kinetic analysis showed that melatonin decreased the V(max) of retinal NOS without changes in the K(m). On the other hand, low concentrations (100 pM) of melatonin significantly reduced retinal L-arginine influx. A decrease in the V(max) of L-arginine uptake was observed in the presence of melatonin, whereas the K(m) remained unchanged. Melatonin significantly inhibited the accumulation of cyclic guanosine monophosphate (cGMP) levels induced by both L-arginine and sodium nitroprusside (SNP). In summary, the present results indicate that melatonin could be a potent inhibitor of the retinal nitridergic pathway.     

Rectovaginal septum endometriosis: a disease with specific diagnosis and treatment

BACKGROUND: The involvement of the rectovaginal septum, of rectum and sigmoid by endometriosis leads to intense symptoms as dysmenorrhea, pelvic pain, deep dyspareunia, tenesmus and hematochezia in young and middle aged women during periods. The diagnosis can be made by tipycal history and vaginal examination, rectal examination, barium enema, proctoscopy and so on. The indications of operation include severe clinic symptoms and failed conservative therapy. The treatment of choice for this type of endometriosis is the surgical resection of affected tissue, in order to relieve patient symptoms, and avoid disease progression. The correct assessment as to the presence and extension of the endometriosis-affected sites such as the rectum, uterosacral ligaments and rectovaginal septum is extremely important to provide better results with the surgical treatment of endometriosis. AIM: To describe the main aspects related to rectovaginal septum endometriosis and offer the general surgeon some information about this enigmatic disease. CONCLUSION: Rectovaginal septum endometriosis is a frequent disease, with specific diagnosis and treatment.     

Increased Prevalence of Myocardial Injury in Patients with SARS-CoV-2 Viremia

BackgroundPatients with coronavirus disease 2019 (COVID-19) have a high prevalence of detectable troponin and myocardial injury. In addition, a subset of patients with COVID-19 has detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral loads. The objective of this study was to understand the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in hospitalized patients with COVID-19.MethodsSARS-CoV-2 plasma viral load was measured in plasma samples drawn from patients hospitalized for COVID-19 at 2 academic medical centers. Baseline characteristics and clinically obtained high-sensitivity cardiac troponin T (hs-cTnT) values were abstracted from the medical record. The main outcome was detectable hs-cTnT (≥6 ng/mL) and myocardial injury (hs-cTnT ≥14 ng/mL; >99th percentile for assay).ResultsA total of 70 hospitalized patients with COVID-19 were included in this study, with 39% females and median age 58 ± 17 years; 21 patients (30%) were found to have detectable SARS-CoV-2 viral load and were classified in the viremia group. Patients with viremia were significantly older than those without viremia. All of the patients with viremia (100%) had detectable troponin during hospitalization compared with 59% of patients without viremia (P = 0.0003). Myocardial injury was seen in 76% of patients with viremia and 38% of those patients without viremia (P = 0.004).ConclusionsHospitalized patients with COVID-19 with SARS-CoV-2 viremia have a significantly higher prevalence of detectable troponin and myocardial injury during their hospitalization compared with patients who did not. This first report of the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in patients with COVID-19 points to additional mechanistic pathways that require deeper study to understand the complex interplay among these unique findings, cardiovascular outcomes, and mortality in COVID-19.     

Acute Nicotine Administration Increases BOLD fMRI Signal in Brain Regions Involved in Reward Signaling and Compulsive Drug Intake in Rats

Background:

Acute nicotine administration potentiates brain reward function and enhances motor and cognitive function. These studies investigated which brain areas are being activated by a wide range of doses of nicotine, and if this is diminished by pretreatment with the nonselective nicotinic receptor antagonist mecamylamine.

Methods:

Drug-induced changes in brain activity were assessed by measuring changes in the blood oxygen level dependent (BOLD) signal using an 11.1-Tesla magnetic resonance scanner. In the first experiment, nicotine naïve rats were mildly anesthetized and the effect of nicotine (0.03–0.6mg/kg) on the BOLD signal was investigated for 10min. In the second experiment, the effect of mecamylamine on nicotine-induced brain activity was investigated.

Results:

A high dose of nicotine increased the BOLD signal in brain areas implicated in reward signaling, such as the nucleus accumbens shell and the prelimbic area. Nicotine also induced a dose-dependent increase in the BOLD signal in the striato-thalamo-orbitofrontal circuit, which plays a role in compulsive drug intake, and in the insular cortex, which contributes to nicotine craving and relapse. In addition, nicotine induced a large increase in the BOLD signal in motor and somatosensory cortices. Mecamylamine alone did not affect the BOLD signal in most brain areas, but induced a negative BOLD response in cortical areas, including insular, motor, and somatosensory cortices. Pretreatment with mecamylamine completely blocked the nicotine-induced increase in the BOLD signal.

Conclusions:

These studies demonstrate that acute nicotine administration activates brain areas that play a role in reward signaling, compulsive behavior, and motor and cognitive function.     

Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice

Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB⁺), neutral (PAS⁺), or mixed (AB/PAS⁺) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015.     

Sobrevida de Pacientes com Insuficiência Cardíaca Aguda e Fração de Ejeção Intermediária em um País em Desenvolvimento – Estudo de Coorte no Sul do Brasil

BackgroundHeart Failure with mid-range Ejection Fraction (HFmEF) was recently described by European and Brazilian guidelines on Heart Failure (HF). The ejection fraction (EF) is an important parameter to guide therapy and prognosis. Studies have shown conflicting results without representative data from developing countries.ObjectiveTo analyze and compare survival rate in patients with HFmEF, HF patients with reduced EF (HFrEF), and HF patients with preserved EF (HFpEF), and to evaluate the clinical characteristics of these patients.MethodsA cohort study that included adult patients with acute HF admitted through the emergency department to a tertiary hospital, reference in cardiology, in south Brazil from 2009 to 2011. The sample was divided into three groups according to EF: reduced, mid-range and preserved. A Kaplan-Meier curve was analyzed according to the EF, and a logistic regression analysis was done. Statistical significance was established as p < 0.05.ResultsA total of 380 patients were analyzed. Most patients had HFpEF (51%), followed by patients with HFrEF (32%) and HFmEF (17%). Patients with HFmEF showed intermediate characteristics related to age, blood pressure and ventricular diameters, and most patients were of ischemic etiology. Median follow-up time was 4.0 years. There was no statistical difference in overall survival or cardiovascular mortality (p=.0031) between the EF groups (reduced EF: 40.5% mortality; mid-range EF 39.7% and preserved EF 26%). Hospital mortality was 7.6%.ConclusionThere was no difference in overall survival rate between the EF groups. Patients with HFmEF showed higher mortality from cardiovascular diseases in comparison with HFpEF patients. (Arq Bras Cardiol. 2021; 116(1):14-23)     

Computer-Aided Methodology for Syndromic Strabismus Diagnosis

Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist.