Chromosome 2p14 Is Linked to Susceptibility to Leprosy

BACKGROUND: A genetic component to the etiology of leprosy is well recognized but the mechanism of inheritance and the genes involved are yet to be fully established. METHODOLOGY: A genome-wide single nucleotide polymorphism (SNP) based linkage analysis was carried out using 23 pedigrees, each with 3 to 7 family members affected by leprosy. Multipoint parametric and non-parametric linkage analyses were performed using MERLIN 1.1.1. PRINCIPAL FINDINGS: Genome-wide significant evidence for linkage was identified on chromosome 2p14 with a heterogeneity logarithm of odds (HLOD) score of 3.51 (rs1106577) under a recessive model of inheritance, while suggestive evidence was identified on chr.4q22 (HLOD 2.92, rs1349350, dominant model), chr. 8q24 (HLOD 2.74, rs1618523, recessive model) and chr.16q24 (HLOD 1.93, rs276990 dominant model). Our study also provided moderate evidence for a linkage locus on chromosome 6q24-26 by non-parametric linkage analysis (rs6570858, LOD 1.54, p = 0.004), overlapping a previously reported linkage region on chromosome 6q25-26. CONCLUSION: A genome-wide linkage analysis has identified a new linkage locus on chromosome 2p14 for leprosy in Pedigrees from China

An integrated and sustainable hydrometallurgical process for enrichment of precious metals and selective separation of copper, zinc, and lead from a roasted sand

This study developed an efficient and sustainable hydrometallurgical process for the enrichment of gold and silver and the stepwise separation of copper, zinc, and lead from sulfated roasted sand of waste printed circuit board smelting ash. Selective separation of copper and zinc was achieved by water leaching, and silver dispersion was reduced by controlling the amount of NaCl added during the leaching process. The results of the water leaching showed that the copper and zinc leaching rates were 99.85% and 99.47%, respectively, whereas the loss rate of silver was 2.1% with optimal leaching parameters. The high-chloride-complex method was used to study the efficient conversion and separation of lead from the leached residue, and the leaching kinetics and conversion mechanism of lead were discussed. The results showed that under the optimal conditions, the leaching rate of lead was 99.79%. Leaching kinetics analysis showed that lead leaching in the high - chlorine system was controlled by a chemical reaction; the apparent activation energy was 53.63 kJ/mol. After the leaching of copper, zinc, and lead, 1.66% Ag and 213 g/t Au were enriched in the leached residue; and the precious metal enrichment goal was reached. The chlorinated leachate showed good recycling performance, and a lead leaching rate of 97.93% was obtained after three circulations. After cooling, crystallization, and purification, lead chloride with a purity of 99.89% and high economic and industrial value was obtained from the lead-rich leachate. This process has favorable and sustainable industrial application prospects

Tuberculosis risk-associated single nucleotide polymorphisms do not show association with leprosy in Chinese population

Objective: Leprosy and tuberculosis (TB) are chronic granulomatous infectious diseases. As well as pathogen and environmental factors, host genetic factors make a substantial contribution to susceptibility to both diseases. More importantly, leprosy and TB also have pathogenic mechanisms and clinical features in common. In this study, the genetic association between leprosy and TB was investigated in a Chinese Han population. Methods: A genetic association study that included 46 TB susceptibility single nucleotide polymorphisms (SNPs) was performed, involving 1150 leprosy cases and 1150 controls from the Chinese Han population. The Sequenom MassARRAY system was used. Results: No significant association was found between the 46 SNPs and leprosy. Therefore, according to the present study, there is no shared susceptibility locus between leprosy and TB in the Chinese Han population. Conclusions: Although leprosy and TB have a number of similar characteristics, no shared susceptibility loci were found in the Chinese Han population. Thus, this study demonstrated that the genetic basis of the pathogenesis of the two diseases may vary greatly

Identification of a Single Nucleotide Polymorphism in NFKBIA with Different Effects on Psoriatic Arthritis and Cutaneous Psoriasis in China

Genome-wide association studies have recently identified a number of non-major histocompatibility complex regions associated with psoriatic arthritis. However, data on Chinese patients with psoriatic arthritis and the differences between psoriatic arthritis and cutaneous psoriasis are limited. This study genotyped 12 single nucleotide polymorphisms in 379 patients with psoriatic arthritis, 376 with cutaneous psoriasis, and 760 healthy controls using Sequenom’s Mass ARRAY system. The aim of the study was to expand the database for psoriatic arthritis and cutaneous psoriasis, and develop a genetic prediction system for the early diagnosis of psoriatic arthritis in the Chinese population. One variant in NFKBIA, rs12883343, had a significantly different association with psoriatic arthritis than with cutaneous psoriasis (p = 4.93×10–10, odds ratio 2.371). This suggests that there are differences in the pathogenesis of psoriatic arthritis and cutaneous psoriasis

Development and evaluation of a droplet digital PCR assay for the diagnosis of paucibacillary leprosy in skin biopsy specimens.

BACKGROUND:The reduced amounts of Mycobacterium leprae (M. leprae) among paucibacillary (PB) patients reflect the need to further optimize methods for leprosy diagnosis. An increasing number of reports have shown that droplet digital polymerase chain reaction (ddPCR) is a promising tool for diagnosis of infectious disease among samples with low copy number. To date, no publications have investigated the utility of ddPCR in the detection of M. leprae. The aim of this study was to develop and evaluate a ddPCR assay for the diagnosis of PB leprosy. METHODOLOGY:The two most sensitive DNA targets for detection of M. leprae were selected from electronic databases for assessment of sensitivity and specificity by quantitative polymerase chain reaction (qPCR) and ddPCR. Control patients (n = 59) suffering from other dermatological diseases were used to define the cut-off of the duplex ddPCR assay. For comparative evaluation, qPCR and ddPCR assays were performed in 44 PB patients and 68 multibacillary (MB) patients. PRINCIPAL FINDINGS:M. leprae-specific repetitive element (RLEP) and groEL (encoding the 65 kDa molecular chaperone GroEL) were used to develop the ddPCR assay by systematically analyzing specificity and sensitivity. Based on the defined cut-off value, the ddPCR assay showed greater sensitivity in detecting M. leprae DNA in PB patients compared with qPCR (79.5% vs 36.4%), while both assays have a 100% sensitivity in MB patients. CONCLUSIONS/SIGNIFICANCE:We developed and evaluated a duplex ddPCR assay for leprosy diagnosis in skin biopsy samples from leprosy patients. While still costly, ddPCR might be a promising diagnostic tool for detection of PB leprosy

HLA-C*15:02 and epidermal growth factor receptor inhibitor-induced erosive pustular dermatosis of the scalp.

Epidermal growth factor receptor inhibitors (EGFRIs) are widely used to treat various types of malignancies. One of the common adverse reactions is cutaneous toxicity, mostly presenting as acneiform eruptions, paronychia and xerosis. Erosive pustular dermatosis of the scalp (EPDS) is a rare cutaneous adverse reaction that develops during treatment with EGFRIs. The pathogenesis of EGFRI-induced EPDS is poorly understood. Here we present three cases of EPDS induced by EGFRIs. The proteins LTA4H (leukotriene A-4 hydrolase), METAP1 (methionine aminopeptidase 1), BID (BH3-interacting domain death agonist), SMAD1 (mothers against decapentaplegic homologue), PRKRA (interferon-inducible double-stranded RNA-dependent protein kinase activator A), YES1 (tyrosine-protein kinase Yes) and EGFL7 (epidermal growth factor-like protein 7) were significantly upregulated in EGFRI-stimulated peripheral blood mononuclear cell cultures, and validated in the lesions. All of the proteins colocalized with CD4+ and CD8+ T-cell expression. Next-generation-based human leucocyte antigen (HLA) typing showed all patients carried HLA-C*15:02, and modelling studies showed that afatinib and erlotinib bound well within the E/F binding pockets of HLA-C*15:02. Moreover, T cells were preferentially activated by EGFRIs in individuals carrying HLA-C*15:02. The case series revealed that EGFRI-induced EPDS may be mediated by drug-specific T cells

Genome-wide linkage results.

<p>Genomic position is shown on the horizontal axis; HLOD(parametric Model)/LOD(non-parametric model) score on the left vertical axis.; Information content on the right vertical axis. Red line indicates results under a recessive model; blue line indicates a dominant model, dashed line indicates nonparametric analysis, and green line indicates information content.</p