BMC Research Notes最新文献

Objective: Frequently touched public surfaces represent fomites. Interestingly, little is known about the microbial contamination of self-ordering touchscreens in fast food restaurants, despite the fact that food is usually consumed with hands shortly after ordering. To bridge this gap, we investigated the bacterial load of self-ordering touchscreens by surface sampling and subsequent identification of dominant morphotypes using MALDI-biotyping. We repeatedly (n = 5) sampled touchscreens in three different restaurants in the greater area of Villingen-Schwenningen, Germany, at times of low (≤ 5 guests) and high occupancy (≥ 20 guests), respectively.

Results: Sampling with Violet Red Bile Agar plates indicated no contamination with Enterobacteriaceae. Sampling with Tryptic Soy Agar plates showed contamination for 28 out of 30 investigated screens, ranging from about 0.07 to 5.7 CFU/cm² (absolute minimum and maximum, respectively). For all restaurants, median bacterial contamination during high occupancy times was 2.8 to 7.5 times higher than during low occupancy. Across all samples, 126 isolates were identified at least on genus level. Samples were dominated by staphylococci and micrococci, indicating human skin microbiota as main source of contamination. The results underline the need for regular touchscreen cleaning and hand hygiene before the meal, in particular at times of high occupancy.

Objective: This pilot study aimed to evaluate whether urine lipoarabinomannan (LAM) testing can be used to monitor tuberculosis treatment response in people living with HIV.

Results: Seventy-five participants were enrolled, of whom 51 (68%) were women, and 43 (57.4%) were antiretroviral therapy naïve. CD4 cell counts were available for 49 participants with a median of 58 cells/mm³ (Interquartile range: 22-175). All participants initially tested positive for urine LAM; however, 12 (16%) converted to negative within two days of starting tuberculosis treatment. During the eight-week follow-up, 49 participants (65.3%) reverted from negative to positive at least once, primarily within the first two weeks, with notable peaks on day 4 (14, 28.6%) and day 5 (10, 20.4%). Of the 53 participants with urine LAM results at eight weeks, 26 participants (49.1%) had sustained urine LAM negativity. There was a significant LAM negativity trend from baseline to week 8 (Cochran-Armitage test for trend, p = 0.002). Urine LAM negativity did not significantly correlate with sputum smear or culture negativity (p = 0.521). These findings indicate that urine lipoarabinomannan testing is unreliable for monitoring tuberculosis treatment in people living with HIV, although repeated measurements offer insight into its performance in real-world settings.

Background: Female genital mutilation/cutting (FGM/C) is a harmful practice that is performed in various parts of the world, especially in Africa, the Middle East, and Asia. Although the Federal Government of Nigeria signed the Violence Against Persons Prohibition (VAPP) Act into law in 2015, little is known about the extent to which the law has contributed to reducing the practice of FGM/C in Nigeria. Therefore, this paper seeks to compare the prevalence of FGM/C before and after the enactment of legislation prohibiting it in Nigeria using data from the Multiple Indicator Cluster Surveys (MICS) of 2007, 2011, 2016/2017, and 2021 (individual recode file), which collected data from women aged 15-49 years across the 36 states of Nigeria, including the Federal Capital Territory (FCT).

Results: The study findings showed that awareness of FGM/C was high across the four (4) rounds of MICS survey datasets, while the prevalence of mothers and their daughters being circumcised has declined. The prevalence of FGM/C practice is lowest in the northeastern region and has been declining steadily in the southwestern region. FGM/C practices are still relatively high in the southeast, southwest, north-central, and northwest, respectively. The findings indicate statistically significant differences in awareness and prevalence of FGM/C before and after the enactment of the VAPP Act, with heterogeneous patterns across geopolitical regions. While these trends are consistent with a potential policy effect, the results should be interpreted as associative rather than causal.

Objective: DNA repair pathways have been leveraged for genetic engineering strategies, including self-eliminating transgenes in insects. In effort towards establishing a self-eliminating transgenic system that leaves desired cargoes like antibodies or anti-viral molecules in Aedes aegypti, steps were taken to generate a plasmid with direct repeats and other necessary transgenic components. Here, we present an account of series of recombination events in E. coli that were encountered during the building of a multi-component plasmid for achieving a cargo-leaving self-eliminating transgenic system in Ae. aegypti.

Results: Step-wise construction of the multi-component plasmid in Stellar™ E. coli competent cells achieved successful modifications of a parent plasmid from a previous study by removing some DNA fragments, incorporating direct repeats and incorporating fluorescent marker gene cassettes (3xP3-DsRed and 3xP3-BFP) in desired locations. However, recombination events resulting in precise and repeatable deletions of small and large DNA fragments were obtained following incorporation of a target site for the in-cis-located I-SceI homing endonuclease into the plasmid. These events were also observed using other E. coli strains like SURE and NEB^® Stable competent cells, although one clone from the NEB^® Stable cells eventually yielded the expected plasmid construct. Analysis of the incorrect plasmids revealed that SSA-like and MMEJ-like DNA repair pathways appeared responsible for the recombination events encountered, suggesting that Aedes aegypti regulatory elements used for control of the homing endonuclease might be leaky in E. coli.