High SARS-CoV-2 Prevalence among Healthcare Workers in Cochabamba,Bolivia

Healthcare workers (HCWs) are at increased risk of SARS-CoV-2 infection. The aim of the study was to estimate the SARS-CoV-2 seroprevalence among HCWs in Cochabamba, Bolivia and to determine the potential risk factors. In January 2021, a cross-sectional SARS-CoV-2 seroprevalence study was conducted in 783 volunteer clinical and non-clinical HCWs in tertiary care facilities. It was based on IgG detection using ELISA, chemiluminiscence, and seroneutralisation tests from dried blood spots. Analysis revealed a high seroprevalence (43.4%) of SARS-CoV-2 IgG antibodies. The combination of anosmia and ageusia (OR: 68.11; 95%-CI 24.83–186.80) was predictive of seropositivity. Belonging to the cleaning staff (OR: 1.94; 95%-CI 1.09–3.45), having more than two children in the same house (OR: 1.74; 95%-CI 1.12–2.71), and having been in contact with a close relative with COVID-19 (OR: 3.53; 95%-CI 2.24–5.58) were identified as risk factors for seropositivity in a multivariate analysis. A total of 47.5% of participants had received medication for COVID-19 treatment or prevention, and only ~50% of symptomatic subjects accessed PCR or antigenic testing. This study confirms a massive SARS-CoV-2 attack rate among HCWs in Cochabamba by the end of January 2021. The main risk factors identified are having a low-skilled job, living with children, and having been in contact with an infected relative in the household.     

Diagnosis and Management of Internal Hernias after Laparoscopic Gastric Bypass

BACKGROUND: Internal hernia is a known complication of laparoscopic Roux-en-Y gastric bypass (LRYGBP). However, no consensus exists regarding optimal diagnostic modality and management. We reviewed the literature and our own experience, and present an algorithm for the diagnosis and management of internal hernia after LRYGBP. METHODS: A retrospective review of 290 retrocolic LRYGBPs was performed to identify those who developed postoperative small bowel obstruction due to internal hernia. Demographics, clinical symptoms, radiologic characteristics, and operative outcomes were analyzed to determine clinical and radiological diagnostic accuracy. RESULTS: Over a 43-month period, 11 out of 290 (3.79%) post-LRYGBP patients with symptoms suggestive of a small bowel obstruction underwent operative exploration. The most common clinical symptoms included intermittent abdominal pain, and/or nausea/vomiting. All patients were initially explored laparoscopically. Etiology of obstructions included internal hernias--6 [at the transverse mesocolon (n = 1), Petersen's space (n = 2), and at the jejunojejunostomy (n = 3)], adhesions (n = 4) and a negative laparoscopy (n = 1). The mean time for development of internal hernias was 13.7 months. Mean loss of BMI units at time of re-operation was 17 kg/m2. Of the 6 patients with internal hernia, 2 (30%) had normal preoperative radiological work-up. On review of the preoperative films by the surgeon, signs of internal herniation were seen in all the patients. Management included initial laparoscopic exploration, lysis of adhesions, reduction of internal hernia and closure of mesenteric defects in all the patients. There were 2 conversions to laparotomy. CONCLUSION: Small bowel obstruction in the post-LRYGBP patient is difficult to diagnose, especially when due to an internal hernia. Most patients present with intermittent abdominal pain and/or nausea. The most frequently used radiologic study is CT scan, which is most accurate when reviewed by the bariatric surgeon preoperatively.     

Recent advances in cardiac positron emission tomography in the clinical management of the cardiac patient

Despite being primarily a research tool, positron emission tomography (PET) has seen slow but steady growth in the clinical management of the cardiac patient. The two major clinical applications of cardiac PET are regional myocardial perfusion imaging to determine the presence and severity of coronary artery disease and metabolic imaging to differentiate viable from nonviable myocardium in patients with ischemic left ventricular dysfunction. Indeed, PET with either nitrogen 13 ammonia or rubidium 82 may offer advantages over current single photon emission computed tomography approaches to assess myocardial perfusion. PETwith fluorine 18 fluorodeoxyglucose is considered the current gold standard for identifying viable myocardium. Finally, the use of PET to quantify myocardial perfusion, metabolism, and innervation has led to key insights into the role of altered microvascular function, substrate metabolism, and neuronal function in a variety of cardiac disease processes.     

Arginine deprivation alters microglial polarity and synergizes with radiation to eradicate non-arginine-auxotrophic glioblastoma tumors

New approaches for the management of glioblastoma (GBM) are an urgent and unmet clinical need. Here, we illustrate that the efficacy of radiotherapy for GBM is strikingly potentiated by concomitant therapy with the arginine-depleting agent ADI-PEG20 in a non-arginine-auxotrophic cellular background (argininosuccinate synthetase 1 positive). Moreover, this combination led to durable and complete radiological and pathological response, with extended disease-free survival in an orthotopic immune-competent model of GBM, with no significant toxicity. ADI-PEG20 not only enhanced the cellular sensitivity of argininosuccinate synthetase 1–positive GBM to ionizing radiation by elevated production of nitric oxide (˙NO) and hence generation of cytotoxic peroxynitrites, but also promoted glioma-associated macrophage/microglial infiltration into tumors and turned their classical antiinflammatory (protumor) phenotype into a proinflammatory (antitumor) phenotype. Our results provide an effective, well-tolerated, and simple strategy to improve GBM treatment that merits consideration for early evaluation in clinical trials.     

Presence of Oil Mineral Aggregates (OMAs) in Surface Sediments from Mexico’s Exclusive Economic Zone,NW Gulf of Mexico

We assessed the presence and distribution of oil mineral aggregates (OMAs) in surficial sediments of Mexican waters in the NW Gulf of Mexico, their potential sources and their correlation with polycyclic aromatic hydrocarbons (PAH). In summer of 2010, OMAs were detected in three shallow sites. In winter of 2011, OMAs were observed in ten sites, two of them in the northernmost area at >?1500 m depth. These particles were possibly advected from the north Gulf and Mississippi area following the deep-water currents of the zone. The OMAs from shallower sites may reflect local pollution sources. PAHs displayed low concentrations in both surveys (from 0.01 to 0.7 µg g^?1 in summer, and from 0.01 to 0.51 µg g^?1 in winter), and showed rather a local origin. The expansion of the oil and port industry in the region is accountable for most of the OMAs detected.     

Evaluation of API Coryne system for identifying coryneform bacteria.

AIM--To identify rapidly and accurately coryneform bacteria, using a commercial strip system. METHODS--Ninety eight strains of Corynebacterium species and 62 additional strains belonging to genera Erysipelothrix, Oerskovia, Rhodococcus, Actinomyces, Archanobacterium, Gardnerella and Listeria were studied. Bacteria were identified using conventional biochemical tests and a commercial system (API-Coryne, BioMèrieux, France). Fresh rabbit serum was added to fermentation tubes for Gardnerella vaginalis isolates. RESULTS--One hundred and five out of the 160 (65.7%) organisms studied were correctly and completely identified by the API Coryne system. Thirty five (21.8%) more were correctly identified with additional tests. Seventeen (10.6%) organisms were not identified by the system and three (1.9%) were misidentified. CONCLUSIONS--The system was a good alternative for identification of coryneform organisms. When occasionally performed with some additional tests, this method permits reliable and rapid identification of coryneform organisms compared with conventional methods.