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Abstract Background For definitive diagnosis of cryptococcal meningitis, Cryptococcus neoformans and/or C. gattii must be identified within cerebral spinal fluid from the patients. The traditional methods for detecting Cryptococcus spp. such as India ink staining and culture are not ideal. Although sensitive and specific enough, detection of cryptococcal antigen polysaccharide has a high dose hook effect. Therefore, the aim of this study was to introduce a new rapid and simple detection method of Cryptococcus neoformans and C. gattii in cerebral spinal fluid. Methods The lateral flow strips combined with recombinase polymerase amplification (LF-RPA) assay was constructed to detect the specific DNA sequences of C. neoformans and C. gattii. The detection limit was evaluated using serial dilutions of C. neoformans and C. gattii genomic DNA. The specificity was assessed by excessive amount of other pathogens genomic DNA. The optimal detection time and amplification temperature were also analyzed. The diagnostic parameters were first calculated using 114 clinical specimens and then compared with that of other diagnostic method. A brief analysis and comparison of different DNA extraction methods was discussed, too. Results The LF-RPA assay could detect 0.64 pg of genomic DNA of C. neoformans per reaction within 10 min and was highly specific for Cryptococcus spp.. The system could work well at a wide range of temperature from 25 to 45 °C. The overall sensitivity and specificity were 95.2 and 95.8% respectively. As amplification template for LF-RPA assay, both cell lysates and genomic DNA produce similar experimental results. Conclusions The LF-RPA system described here is shown to be a sensitive and specific method for the visible, rapid, and accurate detection of Cryptococcus spp. in cerebral spinal fluid and might be useful for clinical preliminary screening of cryptococcal meningitis.

Abstract During China’s urbanization process, rural labor migrants have been suggested to be one important bridge population to change urban-rural distribution on tuberculosis (TB) burden. Aiming to estimate the prevalence of TB infection and to track the active disease development in rural labor migrants, a prospective study was conducted in Shenzhen city, southern China. TB infection was detected using interferon-γ release assay (IGRA). Here we mainly report the characteristics of TB infection in the study population based on the baseline survey. A total of 4,422 eligible participants completed baseline survey in July 2013. QuantiFERON (QFT) positivity rates 17.87% (790/4,422) and was found to be consistent with the local TB epidemic of the areas where the participants immigrated from. Age, smoking, residence registered place, and present of BCG scars were found to be independently associated with QFT positivity. Additionally, evidence for interaction between smoking and age was observed (p for likelihood ratio test

Polysaccharide nucleic acid fractions of bacillus Calmette–Guérin, termed BCG-PSN, have traditionally been used as immunomodulators in the treatment of dermatitis and allergic diseases. While the sales of injectable BCG-PSN have shown steady growth in recent years, no reports of using BCG-PSN powder or its immunotherapeutic effects exist. Here, BCG-PSN powder was applied directly to the skin to evaluate the immunotherapeutic effects on mice infected with Mycobacterium tuberculosis (MTB). In total, 34 μg of BCG-PSN powder could be loaded into a microneedle patch (MNP). Mice receiving BCG-PSN powder delivered via MNP exhibited significantly increased IFN-γ and TNF-α production in peripheral blood CD4 + T cells and improved pathological changes in their lungs and spleens compared to control group mice. The immunotherapeutic effect of BCG-PSN powder delivered via MNP was better than that delivered via intramuscular injection to some extent. Furthermore, MNPs eliminate the side effects of syringes, and this study demonstrated that BCG-PSN can be clinically administrated in powder form.

Background: Perturbed iron homeostasis is a risk factor for tuberculosis (TB) progression and an indicator of TB treatment failure and mortality. Few studies have evaluated iron homeostasis as a TB diagnostic biomarker.Methods: We recruited participants with TB, latent TB infection (LTBI), cured TB (RxTB), pneumonia (PN) and healthy controls (HCs). We measured serum levels of three iron biomarkers including serum iron, ferritin and transferrin, then established and validated our prediction model.Results: We observed and verified that the three iron biomarker levels correlated with patient status (TB, HC, LTBI, RxTB or PN) and with the degree of lung damage and bacillary load in patients with TB. We then built a TB prediction model, neural network (NNET), incorporating the data of the three iron biomarkers. The model showed good performance for diagnosis of TB, with 83% (95% CI 77 to 87) sensitivity and 86% (95% CI 83 to 89) specificity in the training data set (n=663) and 70% (95% CI 58 to 79) sensitivity and 92% (95% CI 86 to 96) specificity in the test data set (n=220). The area under the curves (AUCs) of the NNET model to discriminate TB from HC, LTBI, RxTB and PN were all >0.83. Independent validation of the NNET model in a separate cohort (n=967) produced an AUC of 0.88 (95% CI 0.85 to 0.91) with 74% (95% CI 71 to 77) sensitivity and 92% (95% CI 87 to 96) specificity.Conclusions: The established NNET TB prediction model discriminated TB from HC, LTBI, RxTB and PN in a large cohort of patients. This diagnostic assay may augment current TB diagnostics. [ABSTRACT FROM AUTHOR]

The present cross-sectional study consisted of 18,265 Chinese patients not previously diagnosed with diabetes mellitus, and who underwent physical examination at the Third People's Hospital of Shenzhen between June 2014 and May 2015 (mean patient age, 51.312±15.252 years). The study was composed of 11,770 males and 6,495 females. The aim was to investigate the association between glycated hemoglobin A1c (HbA1c) levels, gender and age. HbA1c values were measured using a Bio-Rad VARIANT? II HbA1c Reorder Pack. All data was collected for analysis of the HbA1c levels in different gender and age groups, in order to investigate the association between HbA1c levels and age. Analysis of the 18,265 total cases and 16,734 cases with HbA1c levels <6.5%, demonstrated a positive correlation between levels of HbA1c and patient age. Linear regression for patient age and HbA1c levels demonstrated that HbA1c (%) = 0.020 x age (years) + 4.523 (r=0.369, P<0.0001) and HbA1c (%) = 0.014 x age (years) + 4.659 (r=0.485, P<0.0001), respectively. HbA1c levels of the male group were significantly higher than those of the female group (P<0.0001). Furthermore, in different gender groups, HbA1c levels gradually rose with increasing age. Therefore, HbA1c levels are associated with age and gender in Chinese populations, and this should be considered when selecting HbA1c as a criterion for future diabetes screening. [ABSTRACT FROM AUTHOR]