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Introduction: Several studies explored the effects of exposure to radiofrequency-electromagnetic field (RF-EMF) and extremely low frequency (ELF) EMF emitted from mobile phones on meningioma among adults. However, the results could not reach an agreement. This meta-analysis was conducted to confirm the relationship between adult meningioma risk and the use of a wireless phone. Methods: Pertinent studies were identified by searching PubMed and Embase up to August 2018. The random- or fixed-effects model was used to combine the results depending on the heterogeneity of the analysis. The publication bias was evaluated using Egger's regression asymmetry test. The subgroup analysis was performed by time since the first use of wireless phone and laterality (ipsilateral/contralateral). Results: Eight studies were enrolled in this meta-analysis. The pooled results suggested that the ever use of wireless phone led to a borderline decreased adult meningioma risk [odds ratio (OR) 0.90; 95% confidence interval (CI) 0.83–0.99] with no heterogeneity (I2 = 5.3%; p = 0.391). A decreased risk of meningioma was seen in short-term (OR = 0.85; 95% CI = 0.77–0.94) users. Neither decreased nor increased risk of meningioma was observed in mid-term (OR = 0.93, 95% CI = 0.75–1.16) and long-term (OR = 1.05, 95% CI = 0.93–1.19) users. Neither ipsilateral (OR = 1.05, 95% CI = 0.90–1.22) nor contralateral (OR = 0.86, 95% CI = 0.62–1.18) wireless phone use was associated with the risk of meningioma. Conclusions: This meta-analysis suggested a relationship between decreased meningioma risk and wireless phone use. However, the findings need further validation. [ABSTRACT FROM AUTHOR]

Animal models have long been used in tuberculosis research to understand disease pathogenesis and to evaluate novel vaccine candidates and anti-mycobacterial drugs. However, all have limitations and there is no single animal model which mimics all the aspects of mycobacterial pathogenesis seen in humans. Importantly mice, the most commonly used model, do not normally form granulomas, the hallmark of tuberculosis infection. Thus there is an urgent need for the development of new alternative in vivo models. The insect larvae, Galleria mellonella has been increasingly used as a successful, simple, widely available and cost-effective model to study microbial infections. Here we report for the first time that G. mellonella can be used as an infection model for members of the Mycobacterium tuberculosis complex. We demonstrate a dose-response for G. mellonella survival infected with different inocula of bioluminescent Mycobacterium bovis BCG lux, and demonstrate suppression of mycobacterial luminesence over 14 days. Histopathology staining and transmission electron microscopy of infected G. mellonella phagocytic haemocytes show internalization and aggregation of M. bovis BCG lux in granuloma-like structures, and increasing accumulation of lipid bodies within M. bovis BCG lux over time, characteristic of latent tuberculosis infection. Our results demonstrate that G. mellonella can act as a surrogate host to study the pathogenesis of mycobacterial infection and shed light on host-mycobacteria interactions, including latent tuberculosis infection. [ABSTRACT FROM AUTHOR]

Abstract Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), is a leading cause of infectious disease mortality. Animal infection models have contributed substantially to our understanding of TB, yet their biological and non-biological limitations are a research bottleneck. There is a need for more ethically acceptable, economical, and reproducible TB infection models capable of mimicking key aspects of disease. Here we demonstrate and present a basic description of how Galleria mellonella (the greater wax moth, Gm) larvae can be used as a low cost, rapid and ethically more acceptable model for TB research. This is the first study to infect Gm with the fully virulent MTB H37Rv, the most widely used strain in research. Infection of Gm with MTB resulted in a symptomatic lethal infection, the virulence of which differed from both attenuated Mycobacterium bovis BCG and auxotrophic MTB strains. The Gm-MTB model can also be used for anti-TB drug screening, although CFU enumeration from Gm is necessary for confirmation of mycobacterial load reducing activity of the tested compound. Furthermore, comparative virulence of MTB isogenic mutants can be determined in Gm. However, comparison of mutant phenotypes in Gm against conventional models must consider the limitations of innate immunity. Our findings indicate that Gm will be a practical, valuable and advantageous additional model to be used alongside existing models to advance tuberculosis research. [ABSTRACT FROM AUTHOR]

Mammalian infection models have contributed significantly to our understanding of the host-mycobacterial interaction, revealing potential mechanisms and targets for novel antimycobacterial therapeutics. However, the use of conventional mammalian models such as mice, are typically expensive, high maintenance, require specialised animal housing, and are ethically regulated. Furthermore, research using Mycobacterium tuberculosis (MTB), is inherently difficult as work needs to be carried out at biosafety level 3 (BSL3). The insect larvae of Galleria mellonella (greater wax moth), have become increasingly popular as an infection model, and we previously demonstrated its potential as a mycobacterial infection model using Mycobacterium bovis BCG. Here we present a novel BSL2 complaint MTB infection model using G. mellonella in combination with a bioluminescent ΔleuDΔpanCD double auxotrophic mutant of MTB H37Rv (SAMTB lux) which offers safety and practical advantages over working with wild type MTB. Our results show a SAMTB lux dose dependent survival of G. mellonella larvae and demonstrate proliferation and persistence of SAMTB lux bioluminescence over a 1 week infection time course. Histopathological analysis of G. mellonella, highlight the formation of early granuloma-like structures which matured over time. We additionally demonstrate the drug efficacy of first (isoniazid, rifampicin, and ethambutol) and second line (moxifloxacin) antimycobacterial drugs. Our findings demonstrate the broad potential of this insect model to study MTB infection under BSL2 conditions. We anticipate that the successful adaptation and implementation of this model will remove the inherent limitations of MTB research at BSL3 and increase tuberculosis research output. [ABSTRACT FROM AUTHOR]

AbstractAcetone is produced from fat metabolism which is increased in diabetic patients due to the disruption of glucose metabolism. Therefore, urinary acetone is expected to be a biomarker for noninvasive diagnosis of diabetes. Although several techniques have been developed for urinary acetone, none meet the clinical needs of automated multi-injection for numerous samples. In this study, we developed automated multi-injection gas chromatography-photoionization detection (AMI-GC-PID) to determine urinary acetone. First, we optimized the sample preprocessing during urine collection and storage before detection and established a standard protocol. The urine was immediately sealed in headspace bottles, stored at 20 °C for 1 h, and equilibrated for 20 min at 80 °C before analysis. Next we evaluated the repeatability of the method and the influence of the urine matrix. The relative standard deviations (RSDs) of the intra-day (nine measurements) and inter-day (three days) measurements were less than 5%. The recovery rate was 97.4% ± 4.6%. AMI-GC-PID was applied to determine urinary acetone in 44 diabetic patients and 29 healthy subjects. The median concentration of urinary acetone was much higher in diabetic patients than in healthy controls (2019 μg/L compared 699 μg/L). The results show that AMI-GC-PID possesses suitable analytical figures of merit for urinary acetone with broad applications in the noninvasive diagnosis of diabetes. [ABSTRACT FROM AUTHOR]