The global, regional, and national burden of tuberculosis in 204 countries and territories, 1990-2019

Structure-guided identification and characterization of potent inhibitors targeting PhoP and MtrA to combat mycobacteria

Mycobacteria are causative agents of tuberculosis (TB), which is a global health concern. Drug-resistant TB strains are rapidly emerging, thereby necessitating the urgent development of new drugs. Two-component signal transduction systems (TCSs) are signaling pathways involved in the regulation of various bacterial behaviors and responses to environmental stimuli. Applying specific inhibitors of TCSs can disrupt bacterial signaling, growth, and virulence, and can help combat drug-resistant TB. We conducted a comprehensive pharmacophore-based inhibitor screening and biochemical and biophysical examinations to identify, characterize, and validate potential inhibitors targeting the response regulators PhoP and MtrA of mycobacteria. The constructed pharmacophore model Phar-PR-n4 identified effective inhibitors of formation of the PhoP-DNA complex: ST132 (IC50 = 29 ± 1.6 µM) and ST166 (IC50 = 18 ± 1.3 µM). ST166 (KD = 18.4 ± 4.3 μM) and ST132 (KD = 14.5 ± 0.1 μM) strongly targeted PhoP in a slow-on, slow-off manner. The inhibitory potency and binding affinity of ST166 and ST132 for MtrAC were comparable to those of PhoP. Structural analyses and molecular dynamics simulations revealed that ST166 and ST132 mainly interact with the α8-helix and C-terminal β-hairpin of PhoP, with functionally essential residue hotspots for structure-based inhibitor optimization. Moreover, ST166 has in vitro antibacterial activity against Macrobacterium marinum. Thus, ST166, with its characteristic 1,2,5,6-tetrathiocane and terminal sulphonic groups, has excellent potential as a candidate for the development of novel antimicrobial agents to combat pathogenic mycobacteria.

Host Cell Death and Modulation of Immune Response against Mycobacterium tuberculosis Infection

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), a prevalent infectious disease affecting populations worldwide. A classic trait of TB pathology is the formation of granulomas, which wall off the pathogen, via the innate and adaptive immune systems. Some key players involved include tumor necrosis factor-alpha (TNF-α), foamy macrophages, type I interferons (IFNs), and reactive oxygen species, which may also show overlap with cell death pathways. Additionally, host cell death is a primary method for combating and controlling Mtb within the body, a process which is influenced by both host and bacterial factors. These cell death modalities have distinct molecular mechanisms and pathways. Programmed cell death (PCD), encompassing apoptosis and autophagy, typically confers a protective response against Mtb by containing the bacteria within dead macrophages, facilitating their phagocytosis by uninfected or neighboring cells, whereas necrotic cell death benefits the pathogen, leading to the release of bacteria extracellularly. Apoptosis is triggered via intrinsic and extrinsic caspase-dependent pathways as well as caspase-independent pathways. Necrosis is induced via various pathways, including necroptosis, pyroptosis, and ferroptosis. Given the pivotal role of host cell death pathways in host defense against Mtb, therapeutic agents targeting cell death signaling have been investigated for TB treatment. This review provides an overview of the diverse mechanisms underlying Mtb-induced host cell death, examining their implications for host immunity. Furthermore, it discusses the potential of targeting host cell death pathways as therapeutic and preventive strategies against Mtb infection.

Global, regional and national burdens of occupational injuries, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

OBJECTIVES

Occupational injuries pose a significant challenge to global health and development. This study aimed to quantify the international and regional burdens of occupational injuries from 1990 to 2019, stratified by specific causes.

METHODS

We analysed global trends in deaths, disability-adjusted life years (DALYs), age-standardised mortality rates (ASMR) and age-standardised DALY rates (ASDR) related to occupational injuries. Specific injuries, including animal contact, drowning, mechanical forces, falls, fire, heat, hot substances, foreign bodies, poisoning and road injuries, were evaluated. Age-stratified and regional analyses were also performed.

RESULTS

Globally, the number of deaths, DALYs, ASMR and ASDR related to occupational injuries declined from 1990 to 2019. The middle Socio-demographic Index (SDI) region exhibited the highest burden, whereas the high SDI region showed the least burden. China and India had the highest occupational injury-related death rates in 2019. Males, particularly those aged 25-44 years, were found to be more vulnerable. Road injuries were the leading cause of death in all age groups. Compared with 1990, mortality numbers and rates decreased significantly by 2019, with the highest burdens experienced in East Asia, South Asia and Southeast Asia.

CONCLUSION

The global decline in occupational injuries is promising; however, certain regions and demographics remain disproportionately affected. Targeted interventions in high-burden areas are crucial to further reduce the impact of occupational injuries.

Global burden of MDR-TB and XDR-TB attributable to high fasting plasma glucose from 1990 to 2019: a retrospective analysis based on the global burden of disease study 2019

PURPOSE

High fasting plasma glucose (HFPG) has been identified as a risk factor for drug-resistant tuberculosis incidence and mortality. However, the epidemic characteristics of HFPG-attributable multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) remain unclear. We aimed to analyze the global spatial patterns and temporal trends of HFPG-attributable MDR-TB and XDR-TB from 1990 to 2019.

METHODS

Utilizing data from the Global Burden of Disease 2019 project, annual deaths and disability-adjusted life years (DALYs) of HFPG-attributable MDR-TB and XDR-TB were conducted from 1990 to 2019. Joinpoint regression was employed to quantify trends over time.

RESULTS

From 1990 to 2019, the deaths and DALYs due to HFPG-attributable MDR-TB and XDR-TB globally showed an overall increasing trend, with a significant increase until 2003 to 2004, followed by a gradual decline or stability thereafter. The low sociodemographic index (SDI) region experienced the most significant increase over the past 30 years. Regionally, Sub-Saharan Africa, Central Asia and Oceania remained the highest burden. Furthermore, there was a sex and age disparity in the burden of HFPG-attributable MDR-TB and XDR-TB, with young males in the 25-34 age group experiencing higher mortality, DALYs burden and a faster increasing trend than females. Interestingly, an increasing trend followed by a stable or decreasing pattern was observed in the ASMR and ASDR of HFPG-attributable MDR-TB and XDR-TB with SDI increasing.

CONCLUSION

The burden of HFPG-attributable MDR-TB and XDR-TB rose worldwide from 1990 to 2019. These findings emphasize the importance of routine bi-directional screening and integrated management for drug-resistant TB and diabetes.

Global prevalence and burden of multidrug-resistant tuberculosis from 1990 to 2019

BACKGROUND

Tuberculosis(TB) remains a pressing public health challenge, with multidrug-resistant tuberculosis (MDR-TB) emerging as a major threat. And healthcare authorities require reliable epidemiological evidence as a crucial reference to address this issue effectively. The aim was to offer a comprehensive epidemiological assessment of the global prevalence and burden of MDR-TB from 1990 to 2019.

METHODS

Estimates and 95% uncertainty intervals (UIs) for the age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR), age-standardized disability-adjusted life years rate (ASR of DALYs), and age-standardized death rate (ASDR) of MDR-TB were obtained from the Global Burden of Disease (GBD) 2019 database. The prevalence and burden of MDR-TB in 2019 were illustrated in the population and regional distribution. Temporal trends were analyzed by using Joinpoint regression analysis to calculate the annual percentage change (APC), average annual percentage change (AAPC) and its 95% confidence interval(CI).

RESULTS

The estimates of the number of cases were 687,839(95% UIs: 365,512 to 1223,262), the ASPR were 8.26 per 100,000 (95%UIs: 4.61 to 15.20), the ASR of DALYs were 52.38 per 100,000 (95%UIs: 22.64 to 97.60) and the ASDR were 1.36 per 100,000 (95%UIs: 0.54 to 2.59) of MDR-TB at global in 2019. Substantial burden was observed in Africa and Southeast Asia. Males exhibited higher ASPR, ASR of DALYs, and ASDR than females across most age groups, with the burden of MDR-TB increasing with age. Additionally, significant increases were observed globally in the ASIR (AAPC = 5.8; 95%CI: 5.4 to 6.1; P < 0.001), ASPR (AAPC = 5.9; 95%CI: 5.4 to 6.4; P < 0.001), ASR of DALYs (AAPC = 4.6; 95%CI: 4.2 to 5.0; P < 0.001) and ASDR (AAPC = 4.4; 95%CI: 4.0 to 4.8; P < 0.001) of MDR-TB from 1990 to 2019.

CONCLUSIONS

This study underscored the persistent threat of drug-resistant tuberculosis to public health. It is imperative that countries and organizations worldwide take immediate and concerted action to implement measures aimed at significantly reducing the burden of TB.

Disseminated tuberculosis in a migrant child

Tuberculosis (TB) poses a major global health threat, substantially affecting children, who contribute notably to new cases and deaths. Diagnosing TB in kids is challenging due to collection issues and the paucibacillary nature of the disease. Disseminated TB, uncommon in children in low TB incidence countries, remains a significant cause of morbidity in migrant populations. We illustrate a rare case of disseminated TB in a middle-childhood boy who migrated from Angola to France, displaying chronic cough, fatigue, weight loss and persistent fever. Investigations revealed widespread TB affecting several organs (lungs, heart, bones and lymph nodes). Prompt diagnosis led to a treatment regimen of four antibiotics (isoniazid, rifampin, pyrazinamide, ethambutol) and corticosteroids, resulting in substantial improvement after 2 months. Subsequent treatment involved two antibiotics (isoniazid and rifampin) for 10 more months. This case underscores the criticality of early identification and comprehensive treatment for disseminated TB, ensuring improved outcomes and reduced risks.