Association of Mycobacterium africanum Infection with Slower Disease Progression Compared with Mycobacterium tuberculosis in Malian Patients with Tuberculosis.
- 作者列表："Baya B","Diarra B","Diabate S","Kone B","Goita D","Sarro YDS","Cohen K","Holl JL","Achenbach CJ","Tolofoudie M","Togo ACG","Sanogo M","Kone A","Kodio O","Dabitao D","Coulibaly N","Siddiqui S","Diop S","Bishai W","Dao S","Doumbia S","Murphy RL","Diallo S","Maiga M
:Mycobacterium africanum (MAF) is known to endemically cause up to 40-50% of all pulmonary TB in West Africa. The aim of this study was to compare MAF with Mycobacterium tuberculosis (MTB) with regard to time from symptom onset to TB diagnosis, and clinical and radiological characteristics. A cross-sectional study was conducted in Bamako, Mali, between August 2014 and July 2016. Seventy-seven newly diagnosed pulmonary TB patients who were naive to treatment were enrolled at Mali's University Clinical Research Center. Sputum cultures were performed to confirm the diagnosis and spoligotyping to identify the mycobacterial strain. Univariate and multivariate analyses were used to identify factors associated with disease progression. Overall, the frequency of female patients was 25% in MAF infection and only 10.0% in MTB infection (OR = 2.9), and MAF was more represented in patients aged ≥ 30 years (57.1% versus 36.7% [OR = 2.3]). More MAF- than MTB-infected patients had a history of a prior TB contact (32.1% versus 14.3% [OR = 2.8]). The mean duration between cough onset and TB diagnosis was 111 days (∼3.7 months) for MAF and 72 days (∼2.4 months) for MTB (P = 0.007). In a multivariate regression, weight loss (body mass index [BMI] < 18.5 kg/m2) and cough duration (> 4 months) were strongly associated with MAF infection (OR = 5.20 [1.49-18.26], P = 0.010, and 4.74 [1.2-18.58], P = 0.02), respectively. Our data show that MAF infection was significantly associated with lower BMI and a longer time between symptom onset and TB diagnosis than MTB. This supports the concept that MAF infection may have slower disease progression and less severe cough symptoms than MTB.
: 已知非洲分枝杆菌 (MAF) 在西非可导致高达 40-50% 的所有肺结核。本研究的目的是比较 MAF 与结核分枝杆菌 (MTB) 从症状发作到结核病诊断的时间，以及临床和影像学特征。2014年8月至 2016年7月在马里巴马科进行了一项横断面研究。在马里大学临床研究中心入组了 77 例初治的新诊断肺结核患者。进行痰培养以确定诊断，并进行分支杆菌分型以鉴定分枝杆菌菌株。使用单变量和多变量分析确定与疾病进展相关的因素。总体而言，女性患者 MAF 感染的频率为 25%，MTB 感染的频率仅为 10.0% (OR = 2.9), MAF 在年龄 ≥ 30 岁的患者中代表更多 (57.1% vs 36.7% [OR = 2.3])。MAF 感染患者比 MTB 感染患者有更多的既往 TB 接触史 (32.1% vs 14.3% [OR = 2.8])。MAF 的咳嗽发作和结核病诊断之间的平均持续时间为 111 天 (3.7 个月)，MTB 为 72 天 (2.4 个月) (P = 0.007)。在多变量回归中，体重减轻 (体重指数 [BMI] 4 个月) 与 MAF 感染强相关 (OR = 5.20 [1.49-18.26]，P = 0.010，4.74 [1.2-18.58]，P = 0.02)。我们的数据显示，与 MTB 相比，MAF 感染与较低的 BMI 和较长的症状发作和结核病诊断之间的时间显著相关。这支持了 MAF 感染的疾病进展可能比 MTB 慢、咳嗽症状不严重的概念。
METHODS:BACKGROUND AND PURPOSE:A critical role for sphingosine kinase/sphingosine-1-phosphate (S1P) pathway in the control of airway function has been demonstrated in respiratory diseases. Here, we address S1P contribution in a mouse model of mild chronic obstructive pulmonary disease (COPD). EXPERIMENTAL APPROACH:C57BL/6J mice have been exposed to room air or cigarette smoke up to 11 months and killed at different time points. Functional and molecular studies have been performed. KEY RESULTS:Cigarette smoke caused emphysematous changes throughout the lung parenchyma coupled to a progressive collagen deposition in both peribronchiolar and peribronchial areas. The high and low airways showed an increased reactivity to cholinergic stimulation and α-smooth muscle actin overexpression. Similarly, an increase in airway reactivity and lung resistances following S1P challenge occurred in smoking mice. A high expression of S1P, Sph-K2 , and S1P receptors (S1P2 and S1P3 ) has been detected in the lung of smoking mice. Sphingosine kinases inhibition reversed the increased cholinergic response in airways of smoking mice. CONCLUSIONS AND IMPLICATIONS:S1P signalling up-regulation follows the disease progression in smoking mice and is involved in the development of airway hyperresponsiveness. Our study defines a therapeutic potential for S1P inhibitors in management of airways hyperresponsiveness associated to emphysema in smokers with both asthma and COPD.
METHODS::The interim results from this 90-day multi-dose, inhalation toxicology study with life-time post-exposure observation has shown an important fundamental difference in persistence and pathological response in the lung between brake dust derived from brake-pads manufactured with chrysotile, TiO2 or chrysotile alone in comparison to the amphiboles, crocidolite and amosite asbestos. In the brake dust exposure groups no significant pathological response was observed at any time. Slight macrophage accumulation of particles was noted. Wagner-scores, were from 1 to 2 (1 = air-control group) and were similar to the TiO2 group. Chrysotile being biodegradable, shows a weakening of its matrix and breaking into short fibers & particles that can be cleared by alveolar macrophages and continued dissolution. In the chrysotile exposure groups, particle laden macrophage accumulation was noted leading to a slight interstitial inflammatory response (Wagner-score 1-3). There was no peribronchiolar inflammation and occasional very slight interstitial fibrosis. The histopathology and the confocal analyses clearly differentiate the pathological response from amphibole asbestos, crocidolite and amosite, compared to that from the brake dust and chrysotile. Both crocidolite and amosite induced persistent inflammation, microgranulomas, and fibrosis (Wagner-scores 4), which persisted through the post exposure period. The confocal microscopy of the lung and snap-frozen chestwalls quantified the extensive inflammatory response and collagen development in the lung and on the visceral and parietal surfaces. The interim results reported here, provide a clear basis for differentiating the effects from brake dust exposure from those following amphibole asbestos exposure. The subsequent results through life-time post-exposure will follow.
METHODS::The respiratory tract is lined by a pseudo-stratified epithelium from the nose to terminal bronchioles. This first line of defense of the lung against external stress includes five main cell types: basal, suprabasal, club, goblet and multiciliated cells, as well as rare cells such as ionocytes, neuroendocrine and tuft/brush cells. At homeostasis, this epithelium self-renews at low rate but is able of fast regeneration upon damage. Airway epithelial cell lineages during regeneration have been investigated in the mouse by genetic labeling, mainly after injuring the epithelium with noxious agents. From these approaches, basal cells have been identified as progenitors of club, goblet and multiciliated cells, but also of ionocytes and neuroendocrine cells. Single-cell RNA sequencing, coupled to lineage inference algorithms, has independently allowed the establishment of comprehensive pictures of cell lineage relationships in both mouse and human. In line with genetic tracing experiments in mouse trachea, studies using single-cell RNA sequencing (RNAseq) have shown that basal cells first differentiate into club cells, which in turn mature into goblet cells or differentiate into multiciliated cells. In the human airway epithelium, single-cell RNAseq has identified novel intermediate populations such as deuterosomal cells, 'hybrid' mucous-multiciliated cells and progenitors of rare cells. Novel differentiation dynamics, such as a transition from goblet to multiciliated cells have also been discovered. The future of cell lineage relationships in the respiratory tract now resides in the combination of genetic labeling approaches with single-cell RNAseq to establish, in a definitive manner, the hallmarks of cellular lineages in normal and pathological situations.