When is Helicobacter pylori acquired in populations in developing countries? A birth-cohort study in Bangladeshi children

Helicobacter pylori colonization is prevalent throughout the world, and is predominantly acquired during childhood. In developing countries, >70% of adult populations are colonized with H. pylori and >50% of children become colonized before the age of 10 years. However, the exact timing of acquisition is unknown. We assessed detection of H. pylori acquisition among a birth cohort of 105 children in Mirzapur, Bangladesh. Blood samples collected at time 0 (cord blood), and at 6, 12, 18, and 24 months of life were examined for the presence of IgG and IgA antibodies to whole cell H. pylori antigen and for IgG antibodies to the CagA antigen using specific ELISAs and immunoblotting. Breast milk samples were analyzed for H. pylori-specific IgA antibodies. Cord blood was used to establish maternal colonization status. H. pylori seroprevalence in the mothers was 92.8%. At the end of the two-year follow-up period, 50 (47.6%) of the 105 children were positive for H. pylori in more than one assay. Among the colonized children, CagA prevalence was 78.0%. A total of 58 children seroconverted: 50 children showed persistent colonization and 8 (7.6%) children showed transient seroconversion, but immunoblot analysis suggested that the transient seroconversion observed by ELISA may represent falsely positive results. Acquisition of H. pylori was not influenced by the mother H. pylori status in serum or breastmilk. In this population with high H. pylori prevalence, we confirmed that H. pylori in developing countries is detectable mainly after the first year of life.     

Langerhans cell hyperplasia in scabies: a mimic of Langerhans cell histiocytosis

AIM: In the absence of mites, the histologic diagnosis of human scabies can be difficult. Scabies can mimic a variety of inflammatory and lymphoproliferative disorders. It is under-recognized that scabies can also mimic Langerhans cell histiocytosis. METHODS: Sixteen examples of scabies were reviewed histologically and immunohistochemically (CD1a, CD3, CD20, CD30 and S100). RESULTS: Immunohistochemical labeling showed florid CD1a and S100 positivity in most cases, indicative of Langerhans cell hyperplasia. Scattered CD30+ lymphocytes were also typically present, within a dense infiltrate, primarily composed of T lymphocytes and eosinophils. CONCLUSION: Because of the prominent CD1a+/S100+ component, scabies can mimic Langerhans cell histiocytosis. This finding should be considered in conjunction with scattered CD30+ cells and clinical features to avoid misdiagnosis.     

Highly economical and direct amination of sp3 carbon using low-cost nickel pincer catalyst

Developing more efficient routes to achieve C–N bond coupling is of great importance to industries ranging from products in pharmaceuticals and fertilizers to biomedical technologies and next-generation electroactive materials. Over the past decade, improvements in catalyst design have moved synthesis away from expensive metals to newer inexpensive C–N cross-coupling approaches via direct amine alkylation. For the first time, we report the use of an amide-based nickel pincer catalyst (1) for direct alkylation of amines via activation of sp³ C–H bonds. The reaction was accomplished using a 0.2 mol% catalyst and no additional activating agents other than the base. Upon optimization, it was determined that the ideal reaction conditions involved solvent dimethyl sulfoxide at 110 °C for 3 h. The catalyst demonstrated excellent reactivity in the formation of various imines, intramolecularly cyclized amines, and substituted amines with a turnover number (TON) as high as 183. Depending on the base used for the reaction and the starting amines, the catalyst demonstrated high selectivity towards the product formation. The exploration into the mechanism and kinetics of the reaction pathway suggested the C–H activation as the rate-limiting step, with the reaction second-order overall, holding first-order behavior towards the catalyst and toluene substrate.

Developing more efficient routes to achieve efficient C–N bond coupling is of great importance to industries ranging from products in pharmaceuticals and fertilizers to biomedical technologies and next-generation electroactive materials.     

Seasonal Variation in Contact Hypersensitivity to Parthenium in Patients of Parthenium Dermatitis

Background:Titer of contact hypersensitivity (TCH) is a measure of contact hypersensitivity to an allergen in an individual. Clinical severity of Parthenium dermatitis varies with season. However, the effect of seasonal variation on the TCH as determined by patch test to Parthenium has not been studied. Objective: To study the effect of seasonal variation on TCH to Parthenium hysterophorus in patients with Parthenium dermatitis.Results:The study had 47 patients, of which 23 were in Group I and 24 in Group II. Mean TCH in Group, I (summer to winter) in period I (summer) was 0.11 ± 0.28 whereas that in period II (winter), was 0.76± 0.41. Similarly, mean TCH in Group II (winter to summer) in period I (winter) and period II (summer) were 0.34± 0.44 and 0.166± 0.32, respectively. The difference in TCH values (95% confidence interval) in the two groups with a change of season was −0.41 (−0.58, −0.24) (P < 0.0001).Conclusions:TCH values in Parthenium dermatitis are lower in the summer season, indicating increased sensitivity to Parthenium allergen in summer.     

Use of Neuroimaging for Children With Seizure in General and Pediatric Emergency Departments

BackgroundSeizure is a common reason for children to visit the emergency department (ED). Pediatric and general EDs may obtain computed tomography (CT) scans of the head for seizure at different rates.ObjectiveTo compare rates of head CT for pediatric seizure between general and pediatric EDs.MethodsThis was a retrospective cohort study using the National Hospital Ambulatory Medical Care Survey for patients <21 years of age presenting to an ED with a chief complaint or diagnosis of seizure between 2006 to 2017. Of these patients, we compared head CT use between general and pediatric EDs among patients with fever, trauma, and co-diagnosis of epilepsy using univariable risk differences and in a multivariable logistic regression model.ResultsMore than 5 (5.4) million (78.8%) and 1.5 million (21.2%) pediatric patients with seizure presented to general and pediatric EDs, respectively. Of those, 22.4% (1.21 million) and 13.2% (192,357) underwent CT scans of the head, respectively, a risk difference of 9.2% (95% confidence interval [CI] 2.3–16.1). General EDs obtained CT scans of the head more often in patients with epilepsy (risk difference 17.9% [95% CI 4.0–31.9]), without fever (12.2% [95% CI 3.1–21.4]), and without trauma (10.6% [95% CI 4.4–16.8]). Presenting to a general ED, being afebrile, or having trauma were associated with head CT with adjusted odds ratios of 1.7 (95% CI 1.0–3.2), 4.9 (95% CI 2.6–9.2), and 2.0 (95% CI 1.2–3.4), respectively. Age, gender, and epilepsy were not associated with head CT among all patients with seizure.ConclusionsChildren with seizure are more likely to undergo CT scans of the head at general EDs compared with pediatric EDs.     

Successful angiographic embolisation of bleeding into the chest wall after chest drain insertion

Peripheral arterial injuries after blunt or penetrating trauma commonly follow injuries to adjacent soft tissue and bone. The traditional approach to these injuries is by open exploration, with identification and ligation of the bleeding vessel. We describe the case of a type II respiratory failure patient who had an enormous pectoral muscle haematoma following chest drain insertion, in whom the bleeding was only controlled by angiographic embolisation following failure of surgical exploration.