Effect of incorporation of bead-beating during DNA extraction for quantitative polymerase chain reaction-based detection of Trichuris trichiura in stool samples in community settings: a systematic review.

This meta-analysis was designed to assess the effect of the addition of a bead-beating (BB) step during DNA extraction to effectively isolate Trichuris trichiura DNA from stool samples for quantitative polymerase chain reaction (qPCR)-based diagnosis. qPCR-based molecular studies comparing the inclusion of a bead-beating step during the DNA extraction from stool samples with extraction without the step were included in the analysis. Studies using real patient samples in community settings were included. The PubMed database and Google search engine were searched in December 2019. Risk of bias and applicability were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. Odds ratios (ORs) for individual studies were combined to estimate the random effects model OR. A total of six independent sub-studies were gathered from two published original articles. The division of the two major studies into six sub-studies was indispensable due to the nature of the study carried out. 128 of the total 192 samples (in all studies) were positive for T. trichiura when BB was used during DNA extraction compared to 108/192 when BB was excluded. The combined OR was 1.66 (95% confidence interval: 1.059 to 2.602). Though only two articles were included in the study, six exclusive individual sub-studies were analyzed. Inherent differences in the background prevalence of helminths in the study population could impact the sensitivity of qPCR. It was found that the inclusion of the BB step during DNA extraction significantly increased the sensitivity of the test. This study was not registered in any database.

First-Generation SARS-CoV-2 Vaccines: A Comparative Analysis between Vaccinated and Unvaccinated Hospitalized Patients Infected with SARS-CoV-2.

Background Severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) variants, which have emerged due to several mutations in spike protein, have a potential to escape immune protection provided by the first-generation vaccines, thereby resulting in breakthrough infections. Objective To identify the socio-demographic factors, clinical features, and outcomes in both vaccinated and unvaccinated hospitalized patients infected with SARS-CoV-2. Method Socio-demographic details, clinical features, and the outcomes among fully vaccinated (double for Covishield/AstraZeneca and BBIBP-CorV and single for Janssen), partially vaccinated, and unvaccinated hospitalized patients with coronavirus disease of 2019 (COVID-19) were collected and analyzed using SPSS version 17. Result Among the hospitalized COVID-19 patients (n=299), 175 (58.5%) patients received a single-dose, 82 (27.4%) double-dose, and 124 (41.5%) did not receive any dose of the COVID-19 vaccines. The risk of SARS-CoV-2 infection when compared between vaccinated and unvaccinated patients was found to be associated among professional degree holders (23.4% versus 9.7%) (p<0.05), professional workers (43.4% vs. 25.0%) (p<0.05), hospitalization to general ward (76.6% vs. 72.6%) (p<0.05), and presence of multiple symptoms (> or equel 3) (86.8% vs. 75.0%) (p>0.05) and comorbidities (> or equal 2) (15.5% vs. 13.7%) (p>0.05). Despite such approximate incidences, the risk of in-hospital mortality among the vaccinated patients was reduced (0.6% vs. 3.2%) (p>0.05), when compared to the unvaccinated patients. The risk of in-hospital mortality was associated with the older age and the presence of multiple comorbidities including bronchial asthma, diabetes, and hypertension. Conclusion Full or partial vaccination against the SARS-CoV-2 variants of concerns might be effective in preventing in-hospital mortality among COVID-19 patients.

The chick blastoderm during diapause, a landmark for optimization of preincubation storage conditions.

At the time of oviposition, the chicken embryo is in its blastodermal stage. The blastoderm displays the unique ability to undergo developmental arrest at low temperatures in a process called "embryonic diapause." In the wild, diapause occurs in freshly laid eggs until the last egg of the clutch has been laid, providing an evolutionary advantage to hens that can synchronously hatch their eggs. The poultry industry utilizes the diapause phenomenon to store eggs before incubation, thereby mitigating their logistic problems. The embryos can only be stored at particular embryonic stages-termed "diapause developmental window" (DW)-if they are to continue to develop normally thereafter. Both cellular and molecular mechanisms define the limits of this DW which broadly comply with onset of blastulation to early gastrulation. Storage conditions affect the cellular and molecular characteristics of the embryo during this window and their ability to successfully resume development (SRD). At storage temperatures of ~12°C to 18°C, embryos can undergo diapause for a short period (up to 7 days (d)) without affecting SRD. However, following longer period of diapause (up to 28 d), embryo stored at ~12°C, but not at ~18°C, can resume development normally. Moreover, eggs can be heated before or during the storage period which will lead to their commencing in development; however, unlike the non-heated embryos, the storage temperature for heated embryos, which are more advance in developing, is not clear. Thus, based on SRD, this review brings evidence supporting the notion that a lower storage temperature is beneficial for early-stage blastoderms whereas a higher storage temperature is favorable for later-stage/gastrulating embryos. Our understanding of the molecular mechanisms underlying the relationship between storage temperature and development stage within the DW is rather limited. However, it is expected to become relevant in light of the effect of selective breeding of modern avian birds on the advancement of embryonic development stage. Thus, this review discusses parameters that are regulated during the DW and affect SRD, and presents the need to adopt new storage techniques. The pre-managerial decision of required duration of storage with manipulation of storage temperature in the currently used storage techniques may improve SRD characteristics.

Primary vesicoureteric reflux in Nepalese children.

BACKGROUND: Vesicoureteric reflux (VUR) is a common urinary tract abnormality observed in children with urinary tract infection and children with VUR are at risk of reflux nephropathy and renal parenchymal damage. In Nepal, till date there are no published series of VUR in children. AIMS AND OBJECTIVES: To study the incidence of VUR in Nepalese children with Urinary tract infection (UTI), to analyze the age and sex wise distribution and clinical course of children with VUR together with the rate of spontaneous resolution of VUR in children METHODOLOGY: A retrospective hospital based study conducted at Department of Paediatrics Patan Hospital from June 2002 to December 2005. Hospital record files of all the children undergoing micturating cystourethrography (MCUG) as part of UTI work up were traced and the files of children with positive VUR were separated and analyzed. RESULTS: Over the 3 and a half years study period total 145 micturating cystourethrograph were done in children with UTI, out of which 35(24%) were positive for VUR. Among the children with VUR, the most common age group was between two to twelve months and the male female ratio was 1.2:1.More than 60% had bilateral VUR and bilateral grade II VUR was the most common finding. Renal scan (DMSA) was done in only 5 cases and out of those two showed renal scaring. Eight cases underwent repeat MCUG after 1-1 1/2 years and spontaneous resolution of VUR was seen in 5 (62.5%) cases. Six cases were lost in follow up, 5 cases went for surgical intervention. CONCLUSION: The incidence of VUR in children with UTI in our part is almost comparable to western data. Children with VUR need regular and long term follow-up.

Effects of storage conditions on hatchability, embryonic survival and cytoarchitectural properties in broiler from young and old flocks.

Storing eggs at low temperature prior to incubation is common practice in the broiler hatchery industry; however, prolonged storage (beyond 7 d) is known to increase early embryonic mortality and reduce chick quality and performance. To better understand the basis of this mortality, we previously published milestone criteria to evaluate morphological and cellular properties of the freshly laid embryo. Using these criteria, in the present study we checked the effects of storage at 18°C and 12°C for up to 28 d on hatchability and chick quality. Furthermore, using a 3D high-resolution episcopic microscopy (HREM) imaging system combined with standard and confocal microscopy and cell viability markers, we analyzed the effects of the different storage conditions on embryonic developmental stage, cytoarchitectural properties, mitotic index and cell survival. A total of 1,483 eggs from a young flock were divided in 2 groups, 18°C and 12°C, and stored for 7, 14, 21, and 28 d. Following storage, randomly selected 1,222 eggs were incubated, and the hatched chicks were evaluated for chick quality parameters. Nonhatched eggs were also analyzed to determine the stage of embryonic mortality. The remaining 261 eggs were isolated and analyzed for developmental stage, cytoarchitecture, mitotic index, and cell death following storage. Hatchability rates beyond 7 d of storage at 12°C were significantly improved compared to 18°C, and chick quality remained high. Similar results were obtained for an old flock's eggs (n = 1,350). Analyzing the embryos, at each time point, we found that at 12°C, the developmental progression during storage slows significantly, mitotic index-which at this temperature may indicate mitotic arrest-increases and the rate of early apoptosis is half than at 18°C. Moreover, the HREM system and histological sections showed that embryos stored at 18°C for prolonged times undergo dramatic cytoarchitectural changes that may be maladaptive to resuming normal development after diapause. We thus demonstrate the usefulness of the milestone criteria for predicting and studying the storage conditions that will allow for better performance in hatchery practice.

Cellular and morphological characterization of blastoderms from freshly laid broiler eggs.

The pioneering study of Eyal-Giladi and Kochav (EG&K; Eyal-Giladi and Kochav, 1976) on the early developmental stages-from fertilization, through oviposition, to the gastrulation process-set the standard for characterizing chicken embryos, and has been used in numerous studies over the years. During uterine development, the chicken embryo undergoes dramatic changes, extremely rapid cell cycles, massive cell death, and axial determination processes. However, once the egg is laid, the temperature drops and the embryo enters into a diapause-like state. This phenomenon is utilized to store fertile eggs prior to incubation. The ability to resume development to hatching, following storage, relies on several factors, including the number of living cells and the embryonic developmental stage. These factors are highly influenced by the storage conditions-mainly duration and temperature. Thus, to study the effects of storage conditions on embryonic viability, a comprehensive characterization of the starting point-shortly after oviposition-is needed. In this study, we characterized freshly laid broiler eggs from Ross 308 flocks for embryonic developmental stage, total cell count, and cell viability. Using the novel high-resolution episcopic microscopy (HREM) system, we show, for the first time, high-resolution 3D morphological models of blastoderms which allow for highly accurate embryonic staging. Staging was also done under a dissecting microscope thus allowing for a direct side-by-side comparison of the two methods. Analysis of freshly laid blastomeres showed that the total nucleus count increases with developmental stage from ∼60,000 at stage X EG&K to ∼130,000 at stage XIII EG&K, whereas the proportion of mitotic index and dying cells at oviposition are ∼2% and ∼5%, respectively. Moreover, staging embryos from young and old flocks revealed that the blastoderms of the old flocks are more developed. Specifically, the predominant embryonic stages were XI and XII EG&K in young and old flocks, respectively. Collectively, we characterized parameters that can serve to analyze the maladaptive effects of prolonged storage under various conditions on embryo survival.