External Bacterial Flora and Antimicrobial Susceptibility Patterns of Staphylococcus spp. and Pseudomonas spp. Isolated from Two Household Cockroaches, Blattella germanica and Blatta orientalis.

A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches (Blattella germanica and Blatta orientalis) collected from households in Tebessa (northeast Algeria). Three major bacterial groups were cultured (total aerobic, enterobacteria, and staphylococci) from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable (P<0.001) and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of (2.1 × 105 CFU/insect), whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second-generation antibiotic cephalosporin cefuroxime.

A short course of corticosteroids reduces the risk of mechanical ventilation and death in patients with moderate to severe COVID 19 pneumonia: results of a retrospective monocentric cohort.

BACKGROUND: Reduced mortality at 28 days in patients treated with corticosteroids was demonstrated, but this result was not confirmed by certain large epidemiological studies. Our aim was to determine whether corticosteroids improve the outcomes of our patients hospitalized with COVID-19 pneumonia. METHODS: Our retrospective, single centre cohort study included consecutive patients hospitalized for moderate to severe COVID-19 pneumonia between March 15 and April 15 2020. An early short course of corticosteroids was given during the second phase of the study. The primary composite endpoint was the need for mechanical ventilation or mortality within 28 days of admission. A multivariate logistic regression model was used to estimate the propensity score, i.e. the probability of each patient receiving corticosteroid therapy based on the initial variables. RESULTS: About 120 consecutive patients were included, 39 in the "corticosteroids group", 81 in the "no corticosteroids group"; their mean ages (±SD) were 66.4 ± 14.1 and 66.1 ± 15.2 years, respectively. Mechanical ventilation-free survival at 28 days was higher in the "corticosteroids group" than in the "no corticosteroids group" (71% and 29% of cases, respectively, p < .0001). The effect of corticosteroids was confirmed with HR .28 (95%CI .10-.79), p = .02. In older and comorbid patients who were not eligible for intensive care, the effect of corticosteroid therapy was also beneficial (HR .36 (95%CI .16-.80), p = .01). CONCLUSION: A short course of corticosteroids reduced the risks of death or mechanical ventilation in patients with moderate to severe COVID-19 pneumonia in all patients and also in older and comorbid patients not eligible for intensive care.

The postischemic environment differentially impacts teratoma or tumor formation after transplantation of human embryonic stem cell-derived neural progenitors.

BACKGROUND AND PURPOSE: Risk of tumorigenesis is a major obstacle to human embryonic and induced pluripotent stem cell therapy. Likely linked to the stage of differentiation of the cells at the time of implantation, formation of teratoma/tumors can also be influenced by factors released by the host tissue. We have analyzed the relative effects of the stage of differentiation and the postischemic environment on the formation of adverse structures by transplanted human embryonic stem cell-derived neural progenitors. METHODS: Four differentiation stages were identified on the basis of quantitative polymerase chain reaction expression of pluripotency, proliferation, and differentiation markers. Neural progenitors were transplanted at these 4 stages into rats with no, small, or large middle cerebral artery occlusion lesions. The fate of each transplant was compared with their pretransplantation status 1 to 4 months posttransplantation. RESULTS: The influence of the postischemic environment was limited to graft survival and occurrence of nonneuroectodermal structures after transplantation of very immature neural progenitors. Both effects were lost with differentiation. We identified a particular stage of differentiation characterized in vitro by a rebound of proliferative activity that produced highly proliferative grafts susceptible to threaten surrounding host tissues. CONCLUSIONS: The effects of the ischemic environment on the formation of teratoma by transplanted human embryonic stem cell-derived neural progenitors are limited to early differentiation stages that will likely not be used for stem cell therapy. In contrast, hyperproliferation observed at later stages of differentiation corresponds to an intrinsic activity that should be monitored to avoid tumorigenesis.

Bacterial load of German cockroach (Blattella germanica) found in hospital environment.

BACKGROUND: Cockroaches are among the most common pests in public dwellings and health facilities. Their presence can raise safety concerns, especially as they maybe carriers of pathogenic organisms. METHODS: This study was carried out to isolate and identify the bacterial flora from German cockroaches (Blattella germanica). Cockroaches collected by hand catches from two public hospital environments in Tebessa city (northeast Algeria) were screened for microbial load from their external surfaces and alimentary tract using standard bacterial protocols. RESULTS: A total of 174 bacterial isolates were isolated from 39 German cockroach specimens. The most common and abundant bacterial species belonged to the Pseudomonas group (23.5%) and Serratia (13.2%). Pathogens like Staphylococcus aureus were also isolated, as well as opportunistic pathogens like Klebsiella species and food spoilage bacteria such as Enterobacter and Citrobacter species were isolated from both external surface and digestive tract of the insect. Generalized linear models (GLM) were performed to analyze the variation of abundances and occurrences of bacterial isolates harboured by B. germanica. The GLMs revealed that the main factors affecting variation of bacterial diversity and abundance were sex and hospital (P < 0.001). CONCLUSION: The findings of this study suggest that German cockroach acts as reservoir and potential vector of some bacterial pathogens.