Multidrug-resistant TB (MDR TB) disease is caused by TB bacteria that are resistant to at least isoniazid and rifampicin, the most effective first-line TB treatment drugs. MDR-TB poses a significant global health challenge due to its resistance to multiple antibiotics. World Health Organization (WHO) and other global health agencies have initiated targeted efforts to control its spread. The recent initiative taken by WHO is ENDTB Universal access to TB prevention and care. However, the eradication of the TB epidemic remains a challenging problem due to the emergence of specialized and modified drug resistance mechanisms. Among these mechanisms, the major facilitator superfamily (MFS) transporters play a crucial role in mediating drug resistance. The Rv0191 efflux transporter protein, a putative member of the MFS, has recently emerged as a potential target for investigating the molecular mechanisms behind the multidrug resistance (MDR) mechanism in Mtb, as it is involved in the efflux of PZA. To investigate the detailed molecular mechanism of Rv0191-mediated drug efflux, two conformations were studied: an outward-open (protonated) conformation for protonation analysis and an inward-open (unprotonated) conformation to examine substrate efflux. Pyrazinamide (PZA), a first-line anti-tuberculosis drug, was selected as the model substrate. Both conformations revealed a central tunnel with a single, distinct binding pocket. The efflux process was explored through a protonation-driven mechanism, highlighting the functional distinctions between the two conformational states. The systems were embedded in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine lipid bilayer, and 500 ns of molecular dynamics simulations in triplicate were conducted for the PZA-docked structure. Trajectory-based structural analyses revealed specific interactions between PZA and the binding pocket, accompanied by conformational changes in Rv0191 that MD simulations indicate substrate movement. The observed structural dynamics suggest a plausible efflux pathway, allowing translocation of PZA from the cytoplasmic to the periplasmic side through the central tunnel, thereby suggesting a plausible mechanism of MFS-mediated drug resistance.

Pneumoconiosis complicated with pulmonary tuberculosis is characterized by high prevalence and disability rates, as well as difficulty in early diagnosis, constituting a serious public health problem. The Chinese Society of Tuberculosis (Chinese Medical Association) and the Society of Labor Hygiene and Occupational Diseases (Chinese Preventive Medicine Association) organized multidisciplinary experts in respiratory diseases, occupational diseases, tuberculosis and other related fields to formulate the Chinese expert consensus on the diagnosis and treatment of pneumoconiosis complicated with tuberculosis. This consensus aims to enhance professional practitioners' understanding of the disease, improve the capacity for early clinical diagnosis, and further advance the prevention and treatment of pneumoconiosis complicated with pulmonary tuberculosis in China. It summarizes 12 key clinical issues and proposes 13 targeted recommendations to address difficulties and misconceptions in clinical practice. This consensus was registered on the International Practice Guidelines Registry Platform (PREPARE-2024CN271). It aims to enhance the standardized diagnosis and treatment of pneumoconiosis complicated by pulmonary tuberculosis, improve patient outcomes, and provide practical guidance for the prevention and control of occupational and infectious diseases in China. The main recommendations are as follows.Recommendation 1: Clinicians and pathologists are advised to pay attention to the mixed pathological features of pneumoconiosis complicated with pulmonary tuberculosis. For patients with pneumoconiosis presenting atypical imaging manifestations or poor response to conventional treatment, pathological specimens should be actively obtained to confirm the diagnosis. Combined use of acid-fast staining, Mycobacterium tuberculosis culture or molecular pathological detection is recommended to increase the detection rate (2C).Recommendation 2: When performing chest CT examinations and dynamic follow-up for pneumoconiosis patients, clinicians and radiologists should focus on multifocal and polymorphic lesions, as well as short-term imaging changes suggestive of active tuberculosis (2C).Recommendation 3: For patients with suspected pulmonary tuberculosis complicated with pneumoconiosis: (1) Be aware that sputum bacteriological tests may yield false-negative results due to dust interference. Repeated sampling or combined detection methods are recommended, including bacteriological and molecular tests on bronchoalveolar lavage fluid (BALF) obtained via bronchoscopy. Results of immunological assays such as the interferon-γ release assay (IGRA) and tuberculin skin test (TST)shall also be combined for comprehensive judgment. (2) In cases with atypical imaging findings and clinical symptoms, bronchoscopy-guided pathological sampling (e.g., EBUS-GS [endobronchial ultrasound with guide sheath], ENB [electromagnetic navigation bronchoscopy]) is prioritized. When microbiological evidence is insufficient, percutaneous lung biopsy or pleural biopsy (for patients with pleural effusion) is suggested to clarify the diagnosis (2B).Recommendation 4: The diagnosis of pneumoconiosis complicated with pulmonary tuberculosis shall follow the integrated diagnostic principle. Provided that patients meet the national diagnostic criteria for pneumoconiosis and pulmonary tuberculosis respectively, a comprehensive assessment shall be conducted combining occupational exposure history, dynamic imaging changes and laboratory results. Patients shall be stratified for managementaccording to the activity of tuberculosis (2C).Recommendation 5: For differential diagnosis between pneumoconiosis complicated with pulmonary tuberculosis and non-tuberculous mycobacterial (NTM) lung disease: (1) NTM lung disease commonly involves the apical and anterior segments of the upper lobes, the right middle lobe and the lingular segment of the left upper lobe. Typical imaging manifestations include a combination of centrilobular nodules and bronchiectasis. (2) Multiple thin-walled cavities are frequently seen in silicosis complicated with NTM lung disease. (3) Pathologically, NTM lesions are dominated by epithelioid granulomas with inconspicuous caseous necrosis. (4) Definitive diagnosis relies on mycobacterial culture and species identification, complying with combined clinical, imaging and microbiological criteria (2C).Recommendation 6: For patients with pneumoconiosis complicated with pulmonary tuberculosis who present progressively enlarged cavities or newly developed cavities accompanied by aggravated symptoms after anti-tuberculosis treatment, radiologists shall evaluate imaging signs of pulmonary aspergillosis, such as the early halo sign and the late air crescent sign within cavities (2C).Recommendation 7: For patients with suspected pneumoconiosis complicated with pulmonary aspergillosis: (1) Bronchoscopy is performed to collect BALF or tissue specimens for fungal culture and pathological examination (gold standard). (2) Conduct BALF galactomannan (GM) test, metagenomic next-generation sequencing (mNGS) or other DNA detection assays. (3) Detect serum specific antibodies against Aspergillus fumigatus (e.g., IgE-m3, IgM) (1A).Recommendation 8: For patients with pneumoconiosis complicated with drug-susceptible pulmonary tuberculosis: (1) Adopt the standard first-line four-drug anti-tuberculosis regimen. (2) Ensure a sufficient treatment course (generally ≥6-8 months). (3) Extend the treatment course to≥9-12 months for patients with severe lesions or concomitant tracheal, pleural or extrapulmonary tuberculosis, so as to improve clinical outcomes and reduce recurrence (2A).Recommendation 9: For patients receiving concurrent treatment for pneumoconiosis (including tetrandrine, nintedanib, pirfenidone, glucocorticoids, bronchodilators, etc.) and rifampicin-containing anti-tuberculosis regimens: (1) Be aware that rifampicin, a potent hepatic enzyme inducer, may accelerate the metabolism of concomitant drugs such as glucocorticoids and nintedanib and reduce their efficacy. (2) Adjust the dose of affected drugs accordingly when rifampicin is initiated or discontinued (1B).Recommendation 10: Extracorporeal membrane oxygenation (ECMO) may be used as a bridge to lung transplantation only for end-stage pneumoconiosis patients complicated with pulmonary tuberculosis awaiting transplantation (2D).Recommendation 11: For end-stage patients with pneumoconiosis complicated with pulmonary tuberculosis who have received adequate and standard anti-tuberculosis therapy, the feasibility of lung transplantation shall be evaluated. Pre-transplant precautions: (1) Ensure complete control of active tuberculosis. (2) Optimize the anti-tuberculosis regimen (e.g., replace rifampicin with rifabutin) to maintain the effective concentration of immunosuppressants (2D).Recommendation 12: For patients with severe, end-stage pneumoconiosis complicated with pulmonary tuberculosis who no longer benefit from active treatment, palliative care and hospice care shall be initiated. Clinicians and medical teams shall communicate fully with patients and their families about the condition, prognosis, treatment options and medical burden. The core goals are to relieve symptoms, alleviate suffering and improve quality of life (2D).Recommendation 13: For patients with pneumoconiosis complicated with tuberculosis who meet the indications for surgical or interventional therapy, a multidisciplinary team shall conduct joint decision-making and implement treatment in a timely manner after full assessment of pulmonary function, nutritional status and surgical risks. Surgical treatment is mainly indicated for patients with drug-resistant tuberculosis with localized lesions, persistent cavitary lesions with ongoing mycobacterial excretion, destroyed lung, massive hemoptysis unresponsive to medical treatment, tuberculous empyema and other critical conditions. Interventional therapy can be applied for emergency treatment of massive hemoptysis, as well as palliative treatment for pulmonary artery stenosis secondary to tuberculosis or pneumoconiosis (2C).

Hydrazine (N2H4) has been extensively utilized during industrial production, while its excessive usage presents substantial risks to human health and ecological systems. In this paper, a new red-emitting camphor-derived benzothiazole-based ratiometric fluorescent probe BTMI-AC was synthesized for selectively and sensitively detecting N2H4 with the large Stokes shift of 223 nm. BTMI-AC exhibited a remarkable fluorescence emission shift from 506 nm to 613 nm after reaction with N2H4, and its ratiometric fluorescence signal ratio (I613/I506) showed a favorable linear relationship with N2H4 concentration with the detection limit as low as 33 nM. The quantitative determination of N2H4 in different soil samples was achieved by using BTMI-AC, suggesting its potential application in the on-site monitoring of N2H4 pollution in the environment. BTMI-AC was also immobilized onto test strips and hydrogel matrices to fabricate the portable solid-state sensing platforms for rapid and visual detection of gaseous and liquid N2H4 through the distinct fluorescence color changes from green to red. Moreover, BTMI-AC was employed for tracking the exogenous concentrations of N2H4 in the live cells, zebrafish and Arabidopsis thaliana. Considering that the metabolism of antituberculosis drugs such as isoniazid (INH) may increase N2H4 levels by enzyme induction and bring potential biological toxicity risk, BTMI-AC could successfully realize the fluorescence imaging of endogenous N2H4 distribution in live cells and zebrafish. We expected that BTMI-AC can offer a sensitive, visual and multi-scenario applicable analytical tool for monitoring N2H4 levels in the environmental samples and biological systems.

Mycobacterium tuberculosis (M. tb), the causative agent of tuberculosis, forms biofilms that contribute significantly to enhanced drug resistance. This study aimed to investigate the role of Rv1904 in the biofilm formation of M. tb. Recombinant strains were constructed for both Mycobacterium smegmatis and M. tb, followed by systematic biological characterization in terms of colony morphology, biofilm-forming ability, sliding motility and aggregation phenotypes, transcription levels of specific genes, tolerance to environmental stresses, intracellular survival capacity, and susceptibility to multiple compounds. The results demonstrated that Rv1904 markedly promoted biofilm formation, upregulated the transcription of the fatty acid synthesis gene fabg4, and enhanced bacterial tolerance to abiotic stresses such as temperature fluctuations, oxidative damage, and nutrient deprivation. These effects collectively improved intracellular survival within host cells. Among the seven tested compounds, thioacetazone (TB1) exhibited the strongest inhibitory effect on biofilm formation. In conclusion, Rv1904 enhances the environmental adaptation and survival advantage of M. tb by promoting biofilm formation, whereas TB1 effectively suppresses Rv1904-mediated biofilm formation. This study reveals the critical role of Rv1904 in biofilm regulation and provides a potential new target for the development of anti-tuberculosis drugs targeting biofilms.

Tuberculosis (TB) pathogenesis is driven by the rapid proliferation of Mycobacterium tuberculosis bacilli, which breach host defenses to invade pulmonary tissue and precipitate active disease. While both natural and synthetic compounds have contributed to successful Mycobacterium tuberculosis (Mtb) therapies, researchers should now prioritize harnessing the synergistic effects of complementary treatments to maximize efficacy. Deploying natural and synthetic small molecules offers a powerful strategy to circumvent drug resistance, enhance Mycobacterium tuberculosis (MTB) therapeutic efficacy, and minimize the toxicities associated with conventional regimens and emerging PROTAC modalities. Consequently, clarifying how these natural and synthetic agents target resistant strains and alter associated genetic biomarkers is essential. This paper reviews recent advancements in natural and synthetic drugs, highlighting their structure-activity relationships to enhance anti-tuberculosis (TB) therapies. Additionally, we present a novel computational framework utilizing target prediction and probability scoring to identify high-potential synthetic compounds for future first-line TB regimens.

The interpretation of genetic variants' association (or not) with phenotypic resistance to newly introduced and repurposed antituberculosis drugs remains challenging, as many mutations detected by whole-genome sequencing (WGS) are classified as of uncertain significance (group 3) or not associated with resistance-interim (group 4) by the World Health Organization (WHO) mutation catalog v2. We evaluated the phenotypic impact of such variants on minimum inhibitory concentrations (MICs) for bedaquiline (BDQ), clofazimine (CFZ), delamanid (DLM), and pretomanid (PA) in Mycobacterium tuberculosis complex isolates from the multi-country DIAMA cohort in sub-Saharan Africa (SSA), which recruited RR/RS-TB patients naïve to these drugs. Among 1,475 isolates with available WGS data, 163 variants met eligibility criteria; due to viable strain unavailability, 89 isolates carrying 29 unique BDQ/CFZ-related and 60 unique DLM/PA-related variants were tested for MIC determination using broth microdilution. Additional structural modeling was performed to explore potential effects of amino-acid substitutions on protein stability. Among BDQ/CFZ-related variants, MICs above the critical concentrations (CCs) were consistently associated with mmpR5 variants, whereas variants in atpE, pepQ, and Rv1979c were not. DLM/PA variants (ddn, fbiA-D, and fgd1) were frequently detected as non-fixed populations, yet rarely yielding MIC values above the CC. Predicted structural destabilization showed no consistent association with MIC values or variant fixation status. Under the conditions tested, phenotypic resistance was not detected for most group 3 and 4 variants detected by WGS. Our data provide evidence from SSA to support improved interpretation of resistance-associated mutations for new and repurposed antituberculosis drugs.IMPORTANCEWhole-genome sequencing increasingly detects Mycobacterium tuberculosis complex mutations classified by the World Health Organization (WHO) mutation catalog v2 as group 3 variants of uncertain significance or group 4 variants not associated with resistance-interim, limiting reliable prediction of resistance to new and repurposed antituberculosis drugs. By generating minimum inhibitory concentration (MIC) data for such variants identified in a multi-country sub-Saharan African cohort, this study provides phenotypic evidence to support future refinement and expansion of the WHO mutation catalog v2. Notably, mmpR5 variants associated with elevated bedaquiline/clofazimine MICs were identified in eight isolates, suggesting that some patients in this cohort may have harbored pre-existing resistance-associated variants yet remained potentially eligible for bedaquiline-containing regimens. These findings contribute to improving the interpretation of genomic resistance data and strengthening surveillance of resistance to bedaquiline, clofazimine, delamanid, and pretomanid.

Chronic liver disease (CLD) constitutes a major global health burden, with high morbidity and mortality, limited treatment options for several etiologies, and an urgent need for novel therapeutic targets. Fibroblast growth factor 1 (FGF1) is a unique member of the FGF family capable of binding all four FGFR subtypes, thereby regulating multiple signaling pathways including PI3K/AKT, Ras/MAPK, and PLCγ, which are involved in metabolism, cell survival, proliferation, and tissue repair. Emerging evidence highlights the multifaceted and context-dependent roles of FGF1 in CLD. In drug-induced liver injury (DILI) caused by anti-tuberculosis drugs, acetaminophen, or doxorubicin, FGF1 confers protection by restoring bile acid homeostasis, reducing oxidative stress, inflammation, and apoptosis. In Metabolic dysfunction-associated steatotic liver disease (MASLD), FGF1 ameliorates hepatic steatosis, oxidative injury, and insulin resistance through downregulation of SREBP1, upregulation of PPARα, and activation of Nrf2-mediated antioxidant responses. Conversely, in primary sclerosing cholangitis (PSC), FGF1 aggravates ductular reaction, biliary senescence, and liver fibrosis via upregulation of SASP and TGF-β1, suggesting that inhibition of the FGF1/FGFR axis may be therapeutic. For alcohol-related liver disease (ALD), although direct experimental evidence is lacking, FGF1 is hypothesized to confer protection given its known activities against oxidative stress, lipid dysregulation, and cell death. Despite its promise, the mitogenic potential of FGF1 raises safety concerns; however, N-terminally modified FGF1 analogs (e.g., FGF1Δ) retain metabolic benefits with reduced proliferative activity. Collectively, FGF1 represents a versatile and disease-dependent regulator in CLD, warranting further mechanistic studies, safety evaluations, and development of targeted analogs as a novel therapeutic strategy for difficult-to-treat liver diseases.