Diagnostic Challenges of Metacarpal Tuberculosis in Paediatrics: A Case Report.

Metacarpal tuberculosis is rare even in endemic areas. This is a report of a 12-year-old girl with gradual, painless swelling of the dorsal aspect of the right hand over a 2-year period. She developed a discharging sinus over the mass after a traumatic incident. The radiographs showed a well-defined, expansile osteolytic lesion. Blood test, fine needle aspiration biopsy and smears were not diagnostic. A second histologic examination with phenotypic test was required for diagnosis and to begin appropriate chemotherapy. Establishing the diagnosis was not straightforward, even though we suspected tuberculosis. Level of Evidence: Level V (Therapeutic).

Retinoic acid induces antimicrobial peptides and cytokines leading to Mycobacterium tuberculosis elimination in airway epithelial cells.

Tuberculosis (TB) is the leading cause of death by a single infectious agent, Mycobacterium tuberculosis (Mtb). Alveolar macrophages and respiratory epithelial cells are the first cells exposed to Mtb during the primary infection, once these cells are activated, secrete cytokines and antimicrobial peptides that are associated with the Mtb contention and elimination. Vitamins are micronutrients that function as boosters on the innate immune system, however, is unclear whether they have any protective activity during Mtb infection. Thus, we investigated the role of vitamin A (retinoic acid), vitamin C (ascorbic acid), vitamin D (calcitriol), and vitamin E (alfa-tocopherol) as inductors of molecules related to mycobacterial infection in macrophages and epithelial cells. Our results showed that retinoic acid promotes the expression of pro- and anti-inflammatory molecules such as Thymic stromal lymphopoietin (TSLP), ß-defensin-2, IL-1ß, CCL20, ß-defensin-3, Cathelicidin LL-37, TGF-ß, and RNase 7, whereas calcitriol, ascorbic acid, and α-tocopherol lead to an anti-inflammatory response. Treatment of Mtb-infected epithelial cells and macrophage-like cells with the vitamins showed a differential response, where calcitriol reduced Mtb in macrophages, while retinoic acid reduced infection in epithelial cells. Thereby, we propose that a combination of calcitriol and retinoic acid supplementation can drive the immune response, and promotes the Mtb elimination by increasing the expression of antimicrobial peptides and cytokines, while simultaneously modulating inflammation.

'TB or not TB': the conundrum of pre-European contact tuberculosis in the Pacific.

Tuberculosis (TB) is a major global health threat, infecting one-third of the world's population. Despite this prominence, the age, origin and spread of the disease have been topics of contentious debate. Molecular studies suggest that Mycobacterium tuberculosis 'sensu stricto', the most common strain of TB infecting humans today, originated in Africa and from there spread into Europe and Asia. The M. tuberculosis strains most commonly found across the Pacific and the Americas today are most closely related to European strains, supporting a hypothesis that the disease only reached these regions relatively recently via European sailors or settlers. However, this hypothesis is inconsistent with palaeopathological evidence of TB-like lesions in human remains from across the Pacific that predate European contact. Similarly, genetic evidence from pre-European South American mummies challenges the notion of a European introduction of the disease into the Pacific. Here, we review the complex evidence for the age and origin of TB in the Pacific, and discuss key gaps in our knowledge and how these may be addressed. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.

Discovery of thienothiazolocarboxamide analogues as novel anti-tubercular agent.

In order to identify anti-tubercular agents with a novel scaffold, commercial libraries of small organic compounds were screened against a fluorescent strain of Mycobacterium tuberculosis H37Rv, using a dual phenotypic assay. Compounds were assessed against bacteria replicating in broth medium, as well as inside macrophages, and thienothiazolocarboxamide (TTCA) scaffold was identified as hit in both assays, with submicromolar inhibitory concentrations. Derivatives of TTCA were further synthesized and evaluated for their inhibitory effects on M.tuberculosis H37Rv. In the present study we report the structure-activity relationship of these TTCA derivatives. Compounds 28, 32 and 42 displayed good anti-tubercular activities, as well as favorable ADME and PK properties. Compound 42 exhibited excellent oral bioavailability in mice with high distribution to lungs, within 1 h. It was found to be efficacious in a dose dependent manner in a murine model of M. tuberculosis infection. Hence, compound 42 is now under evaluation as a potential lead candidate for treatment of tuberculosis.

Macrophage-Targeted Isoniazid-Selenium Nanoparticles Promote Antimicrobial Immunity and Synergize Bactericidal Destruction of Tuberculosis Bacilli.

Pathogenesis hallmarks for tuberculosis (TB) are the Mycobacterium tuberculosis (Mtb) escape from phagolysosomal destruction and limited drug delivery into infected cells. Several nanomaterials can be entrapped in lysosomes, but the development of functional nanomaterials to promote phagolysosomal Mtb clearance remains a big challenge. Here, we report on the bactericidal effects of selenium nanoparticles (Se NPs) against Mtb and further introduce a novel nanomaterial-assisted anti-TB strategy manipulating Ison@Man-Se NPs for synergistic drug-induced and phagolysosomal destruction of Mtb. Ison@Man-Se NPs preferentially entered macrophages and accumulated in lysosomes releasing Isoniazid. Surprisingly, Ison@Man-Se/Man-Se NPs further promoted the fusion of Mtb into lysosomes for synergistic lysosomal and Isoniazid destruction of Mtb. Concurrently, Ison@Man-Se/Man-Se NPs also induced autophagy sequestration of Mtb, evolving into lysosome-associated autophagosomal Mtb degradation linked to ROS-mitochondrial and PI3K/Akt/mTOR signaling pathways. This novel nanomaterial-assisted anti-TB strategy manipulating antimicrobial immunity and Mtb clearance may potentially serve in more effective therapeutics against TB and drug-resistant TB.

A Repurposing Approach for Uncovering the Anti-Tubercular Activity of FDA-Approved Drugs with Potential Multi-Targeting Profiles.

Tuberculosis (TB) is one of the top 10 causes of death worldwide. This scenario is further complicated by the insurgence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. The identification of appropriate drugs with multi-target affinity profiles is considered to be a widely accepted strategy to overcome the rapid development of resistance. The aim of this study was to discover Food and Drug Administration (FDA)-approved drugs possessing antimycobacterial activity, potentially coupled to an effective multi-target profile. An integrated screening platform was implemented based on computational procedures (high-throughput docking techniques on the target enzymes peptide deformylase and Zmp1) and in vitro phenotypic screening assays using two models to evaluate the activity of the selected drugs against Mycobacterium tuberculosis (Mtb), namely, growth of Mtb H37Rv and of two clinical isolates in axenic media, and infection of peripheral blood mononuclear cells with Mtb. Starting from over 3000 FDA-approved drugs, we selected 29 marketed drugs for submission to biological evaluation. Out of 29 drugs selected, 20 showed antimycobacterial activity. Further characterization suggested that five drugs possessed promising profiles for further studies. Following a repurposing strategy, by combining computational and biological efforts, we identified marketed drugs with relevant antimycobacterial profiles.

Identification of a pyrimidinetrione derivative as the potent DprE1 inhibitor by structure-based virtual ligand screening.

Despite the increasing need of new antituberculosis drugs, the number of agents approved for the market has fallen to an all-time low. In response to the emerging drug resistance followed, structurally unique chemical entities will be highlighted. decaprenylphosphoryl-ß-d-ribose oxidase (DprE1) participating in the biosynthesis of mycobacterium cell wall is a highly vulnerable and validated antituberculosis target. On the basis of it, a systematic strategy was applied to identify a high-quality lead compound (compound 50) that inhibits the essential enzyme DprE1, thus blocking the synthesis of the mycobacterial cell wall to kill M. tuberculosis in vitro and in vivo. Correspondingly, the rational design and synthetic strategy for compound 50 was reported. Notably, the compound 50 has been confirmed to be no toxicity. Altogether, our data suggest the compound 50 targeting DprE1 is a promising candidate for the tuberculosis (TB) therapy.

Cigarette Smoking Impairs the Bioenergetic Immune Response to Mycobacterium tuberculosis Infection.

Smoking is a major risk factor driving the tuberculosis epidemic, and smokers' alveolar macrophages (AM) demonstrate significant immune defects after infection. Recently, macrophage glycolytic reprogramming has emerged as crucial in the early host immune response to Mycobacterium tuberculosis (Mtb) infection. In the present study, we sought to compare baseline metabolic characteristics and the glycolytic response to infection of human AM from smokers and nonsmokers. AM were obtained at bronchoscopy, and extracellular flux analyses were performed to determine baseline metabolic characteristics compared with human monocyte-derived macrophages (MDM). Metabolic characterization of AM from smokers and nonsmokers was performed similarly. After infection with Mtb, differences in glycolytic response were measured by extracellular flux analyses and gene expression analyses and correlated with production of glycolysis-driven IL-1ß and prostaglandin E2. Similar experiments were performed in cigarette smoke extract-treated MDM as an alternative model. At baseline, human AM from nonsmokers have a significantly lower extracellular acidification rate/oxygen consumption rate ratio than MDM (P < 0.05), but they retain substantial glycolytic reserve. Compared with nonsmokers' AM, smokers' AM demonstrate reduced metabolic activity, reduced glycolytic reserve (P = 0.051), and reduced spare respiratory capacity (P < 0.01). After infection with Mtb, smokers' AM have significantly reduced glycolytic response, as measured by extracellular flux analyses (P < 0.05) and glycolytic gene expression analyses. Cigarette smoke extract-treated MDM similarly demonstrate reduced metabolic activity and reserves, as well as impaired glycolytic response to infection. Human AM demonstrate metabolic plasticity that allows glycolytic reprogramming to occur after Mtb infection. In smokers, this metabolic reserve is significantly attenuated, with consequent impairment of the glycolytic response to infection.

All-trans Retinoic Acid Augments Autophagy during Intracellular Bacterial Infection.

Vitamin A deficiency strongly predicts the risk of developing tuberculosis (TB) in individuals exposed to Mycobacterium tuberculosis (Mtb). The burden of antibiotic-resistant TB is increasing globally; therefore, there is an urgent need to develop host-directed adjunctive therapies to treat TB. Alveolar macrophages, the niche cell for Mtb, metabolize vitamin A to all-trans retinoic acid (atRA), which influences host immune responses. We sought to determine the mechanistic effects of atRA on the host immune response to intracellular bacterial infection in primary human and murine macrophages. In this study, atRA promoted autophagy resulting in a reduced bacterial burden in human macrophages infected with Mtb and Bordetella pertussis, but not bacillus Calmette-Guérin (BCG). Autophagy is induced by cytosolic sensing of double-stranded DNA via the STING/TBK1/IRF3 axis; however, BCG is known to evade cytosolic DNA sensors. atRA enhanced colocalization of Mtb, but not BCG, with autophagic vesicles and acidified lysosomes. This enhancement was inhibited by blocking TBK1. Our data indicate that atRA augments the autophagy of intracellular bacteria that trigger cytosolic DNA-sensing pathways but does not affect bacteria that evade these sensors. The finding that BCG evades the beneficial effects of atRA has implications for vaccine design and global health nutritional supplementation strategies. The ability of atRA to promote autophagy and aid bacterial clearance of Mtb and B. pertussis highlights a potential role for atRA as a host-directed adjunctive therapy.

GeneChip analysis of resistant Mycobacterium tuberculosis with previously treated tuberculosis in Changchun.

BACKGROUND: With the widespread use of rifampicin and isoniazid, bacterial resistance has become a growing problem. Additionally, the lack of relevant baseline information for the frequency of drug-resistant tuberculosis (TB) gene mutations is a critical issue, and the incidence of this infection in the city of Changchun has not investigated to date. However, compared with the slow traditional methods of drug susceptibility testing, recently developed detection methods, such as rifampicin and isoniazid resistance-related gene chip techniques, allow for rapid, easy detection and simultaneous testing for mutation frequency and drug resistance. METHODS: In this study, the rifampicin and isoniazid resistance-related gene mutation chip method was employed for an epidemiological investigation. To assess the gene mutation characteristics of drug-resistant TB and evaluate the chip method, we tested 2143 clinical specimens from patients from the infectious diseases hospital of Changchun city from January to December 2016. The drug sensitivity test method was used as the reference standard. RESULTS: The following mutation frequencies of sites in the rifampicin resistance gene rpoB were found: Ser531Leu (52.6%), His526Tyr (12.3%), and Leu511Pro (8.8%). The multidrug-resistance (MDR)-TB mutation frequency was 34.7% for rpoB Ser531Leu and katG Ser315Thr, 26.4% for rpoB Ser531Leu and inhA promoter - 15 (C → T), and 10.7% for rpoB His526Tyr and katG Ser315Thr. In addition, drug susceptibility testing served as a reference standard. In previously treated clinical cases, the sensitivity and specificity of GeneChip were 83.1 and 98.7% for rifampicin resistance, 79.9 and 99.6% for isoniazid resistance, and 74.1 and 99.8% for MDR-TB. CONCLUSIONS: Our experimental results show that the chip method is accurate and reliable; it can be used to detect the type of drug-resistant gene mutation in clinical specimens. Moreover, this study can be used as a reference for future research on TB resistance baselines.

Protective efficacy of a lipid antigen vaccine in a guinea pig model of tuberculosis.

The bacillus Calmette Guérin (BCG) vaccine, the only licensed vaccine against TB, displays partial and variable efficacy, thus making the exploitation of novel vaccination strategies a major priority. Most of the current vaccines in pre-clinical or clinical development are based on the induction of T cells recognizing protein antigens. However, a large number of T cells specific for mycobacterial lipids are induced during infection, suggesting that lipid-based vaccines might represent an important component of novel sub-unit vaccines. Here, we investigated whether immunization with defined mycobacterial lipid antigens induces protection in guinea pigs challenged with M. tuberculosis. Two purified mycobacterial lipid antigens, the diacylated sulfoglycolipids (Ac2SGL) and the phosphatidyl-myo-inositol dimannosides (PIM2) were formulated in biophysically characterized liposomes made of dimethyl-dioctadecyl-ammonium (DDA) and synthetic trehalose 6,6'-dibehenate (TDB). In three protection trials, a reduction of bacterial load in the spleen of inoculated animals was consistently observed compared to the unvaccinated group. Moreover, a reduction in the number of lesions and severity of pathology was detected in the lungs and spleen of the lipid vaccine group compared to unvaccinated controls. As the degree of protection achieved is similar to that observed using protein antigens in the same guinea pig model, these promising results pave the way to future investigations of lipid antigens as subunit vaccines.

Evaluation of in vivo antimycobacterial activity of some folklore medicinal plants and enumeration of colony forming unit in murine model.

OBJECTIVES: The present study was carried out to investigate the in vivo antimycobacterial activity of methanol extract of Alstonia scholaris and Mucuna imbricata in murine model. MATERIALS AND METHODS: Female BALB/c mice were infected with the Mycobacterium tuberculosis H37Rv suspension. Extracts were administered orally for 2 weeks from 7th day postinfection at a dose of 200 mg/kg and rifampicin at 20 mg/kg as standard. The synergistic groups were 10 and 100 mg/kg for rifampicin and extract, respectively. RESULTS: The final body weight of mycobacteria-infected group was significantly reduced (15.41 ± 0.42, P < 0.01), but following treatment with the plant extract plus rifampicin could elevate the body weight. Colony forming unit (CFU) count of lung (8.71 ± 0.01) and spleen (8.59 ± 0.01) was significantly higher in infected and untreated group (P < 0.01). It was observed that activity of the synergistic group displayed powerful and maximum response against tuberculosis (TB) infection with lower CFU counts. Histopathology study showed cells such as lymphocytes, epithelioid, Langhans giant cell, and fibrous tissue proliferation in lungs; depletion of lymphocytes in the spleen. CONCLUSIONS: The data indicate that methanol extract of A. scholaris has potential antimycobacterial activity, and the synergistic group consisting of rifampicin and A. scholaris could be a rational choice for the treatment of TB.

Animal Models of Tuberculosis: An Overview.

This article provides an overview of the animal models currently used in tuberculosis research, both for understanding the basic science of the disease process and also for practical issues such as testing new vaccine candidates and evaluating the activity of potential new drugs. Animals range in size, from zebrafish to cattle, and in degrees of similarity to the human disease from both an immunological and pathologic perspective. These models have provided a great wealth of information (impossible to obtain simply from observing infected humans), but we emphasize here that one must use care in interpreting or applying this information, and indeed the true art of animal modeling is in deciding what is pertinent information and what might not be. These ideas are discussed in the context of current approaches in vaccine and drug development, including a discussion of certain limitations the field is currently facing in such studies.

Non-Human Primate Models of Tuberculosis.

Among the animal models of tuberculosis (TB), the non-human primates, particularly rhesus macaques (Macaca fascicularis) and cynomolgus macaques (Macaca mulatta), share the greatest anatomical and physiological similarities with humans. Macaques are highly susceptible to Mycobacterium tuberculosis infection and manifest the complete spectrum of clinical and pathological manifestations of TB as seen in humans. Therefore, the macaque models have been used extensively for investigating the pathogenesis of M. tuberculosis infection and for preclinical testing of drugs and vaccines against TB. This review focuses on published major studies that exemplify how the rhesus and cynomolgus macaques have enhanced and may continue to advance global efforts in TB research.

Tuberculosis in an autosomal recessive case of chronic granulomatous disease due to mutation of the NCF1 gene

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Arabinosylated lipoarabinomannan (Ara-LAM) mediated intracellular mechanisms against tuberculosis infection: involvement of protein kinase C (PKC) mediated signaling.

Tuberculosis causes severe immunosuppression thereby ensuring the loss of the host protective immune responses. During Mycobacterium tuberculosis infection, the pathogen modulates TLR-2 receptor down-stream signaling, indicating the possible involvement of TLR-2 in the regulation of the host immune response. Moreover, different PKC isoforms are also involved in the course of infection. Arabinosylated lipoarabinomannan (Ara-LAM) possesses immuno-modulatory properties which induce the pro-inflammatory responses via induction of TLR-2-mediated signaling. Here, we found that pretreatment of M. tuberculosis-infected macrophages with Ara-LAM caused a significant increase in the conventional PKC expression along with their active association with TLR-2. This association activated the TLR-2 -mediated downstream signaling, facilitating the activation of MAP kinase P38. All these events culminated in the up-regulation of proinflammatory response, which was abrogated by treatment with PKC-α and P38 inhibitors. Moreover, pretreatment of macrophages with Ara-LAM abrogated the IL-10 production while restored MHC-II expression in the infected macrophages. This study demonstrates that Ara-LAM confers protection against tuberculosis via TLR-2/PKC signaling crosstalk which is responsible for the induction of host protective immune response against tuberculosis.

Antituberculosis: synthesis and antimycobacterial activity of novel benzimidazole derivatives.

A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H37Rv (MTB-H37Rv) and INH-resistant M. tuberculosis (INHR-MTB) strains using agar dilution method. Three of them displayed good activity with MIC of less than 0.2 µM. Compound ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-(5-(4-fluorophenyl)pyridin-3-ylphenyl-1H-benzo[d]imidazole-5-carboxylate (5 g) was found to be the most active with MIC of 0.112 µM against MTB-H37Rv and 6.12 µM against INHR-MTB, respectively.

[Paleopathology of Herculaneum's population (79 D.C.)]. / Aspetti di paleopatologia della popolazione di Ercolano (79 D.C.).

In 1982, some occasional excavations in the area corresponding to the ancient beach of Ercolano brought to light the rests of around 250 individuals, victims of the eruption of the Vesuvius. This exceptional recovery constitutes an essential patrimony for the reconstruction of the paleobiology and the paleopathology of the human populations in Roman epoch, in relationship not only to the style of life but also to the social and economic status. Notwithstanding the bone alterations due to the exposition to high temperature, the human remains present traces of illness. Among these we find rheumatic pathologies and arthrosis of the vertebral column. The high frequency of occupational markers (enthesopaties and sindesmopaties) suggests that the most part of the population (juveniles included) exercised hand work. Among the infectious pathologies we report cases of the tuberculosis and brucellosis.

Corticosteroid therapy, vitamin D status, and inflammatory cytokine profile in the HIV-tuberculosis immune reconstitution inflammatory syndrome.

BACKGROUND: Tuberculosis-immune reconstitution inflammatory syndrome (TB-IRIS) in patients coinfected with human immunodeficiency virus (HIV) and tuberculosis starting antiretroviral therapy (ART) is associated with hypercytokinemia. As adjunctive corticosteroid therapy and vitamin D have immunomodulatory properties, we investigated the relationship between cytokine/chemokine profiles, corticosteroid use, and vitamin D deficiency in TB-IRIS patients. METHODS: Plasma from 39 TB-IRIS and 42 non-IRIS patients was collected during a prospective study of HIV-associated tuberculosis patients starting ART. In total, 26% of patients received corticosteroid (CTC) therapy pre-ART for severe tuberculosis. Concentrations of total 25-hydroxyvitamin D (25(OH)D) and 14 cytokines/chemokines were determined at ART initiation and 2 weeks later. RESULTS: Patients prescribed concurrent CTC had lower interferon γ (IFN-γ), IP-10, tumor necrosis factor (TNF), interleukin (IL)-6, IL-8, IL-10, IL-12p40, and IL-18 pre-ART (P ≤ .02). TB-IRIS presented at 12 days (median) of ART, irrespective of CTC use. In patients who developed TB-IRIS (not on CTC) IL-6, IL-8, IL-12p40, IL-18, IP-10, and TNF increased during 2 weeks (P ≤ .04) of ART. Vitamin D deficiency (total 25(OH)D <75 nmol/L) was highly prevalent (89%) at baseline. Although vitamin D deficiency at either baseline or 2 weeks was not associated with TB-IRIS, in those not on CTC the median 25(OH)D decreased during 2 weeks (P = .004) of ART. Severe vitamin D deficiency (total 25(OH)D <25 nmol/L) was associated with higher baseline TNF, IL-6, and IL-8 irrespective of IRIS status. CONCLUSIONS: CTC modifies the inflammatory profile of those who develop TB-IRIS. The association between severe vitamin D deficiency and elevated proinflammatory cytokines support a study of vitamin D supplementation in HIV-TB co-infected patients starting ART.