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Essai clinique et expérimental sur la fièvre des tuberculeux (toxicité des crachats, toxicité des urines) / par Le Docteur Edouard Chretien.

Paris : Steinheil, 1896.




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Essai sur la puberté chez la femme : psychologie, physiologie, pathologie / par Marthe Francillon.

Paris : F. Alcan, 1906.




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Anti-tuberculosis measures in England / F. J. H. Coutts.

England : Society of Medical Officers of Health, [192-?]




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Tuberculosis statistics : summary of the report / addressed by Dr. S. Rosenfeld (Vienna) to the Health Committee of the Leage of Nations.

England : League of Nations, 1925.




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Adaptive Resetting of Tuberoinfundibular Dopamine (TIDA) Network Activity during Lactation in Mice

Giving birth triggers a wide repertoire of physiological and behavioral changes in the mother to enable her to feed and care for her offspring. These changes require coordination and are often orchestrated from the CNS, through as of yet poorly understood mechanisms. A neuronal population with a central role in puerperal changes is the tuberoinfundibular dopamine (TIDA) neurons that control release of the pituitary hormone, prolactin, which triggers key maternal adaptations, including lactation and maternal care. Here, we used Ca2+ imaging on mice from both sexes and whole-cell recordings on female mouse TIDA neurons in vitro to examine whether they adapt their cellular and network activity according to reproductive state. In the high-prolactin state of lactation, TIDA neurons shift to faster membrane potential oscillations, a reconfiguration that reverses upon weaning. During the estrous cycle, however, which includes a brief, but pronounced, prolactin peak, oscillation frequency remains stable. An increase in the hyperpolarization-activated mixed cation current, Ih, possibly through unmasking as dopamine release drops during nursing, may partially explain the reconfiguration of TIDA rhythms. These findings identify a reversible plasticity in hypothalamic network activity that can serve to adapt the dam for motherhood.

SIGNIFICANCE STATEMENT Motherhood requires profound behavioral and physiological adaptations to enable caring for offspring, but the underlying CNS changes are poorly understood. Here, we show that, during lactation, neuroendocrine dopamine neurons, the "TIDA" cells that control prolactin secretion, reorganize their trademark oscillations to discharge in faster frequencies. Unlike previous studies, which typically have focused on structural and transcriptional changes during pregnancy and lactation, we demonstrate a functional switch in activity and one that, distinct from previously described puerperal modifications, reverses fully on weaning. We further provide evidence that a specific conductance (Ih) contributes to the altered network rhythm. These findings identify a new facet of maternal brain plasticity at the level of membrane properties and consequent ensemble activity.




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Zuberbühler aids Nyon festival

Former Swiss internationals including Pascal Zuberbühler helped turn the UEFA European Women's Under-17 Championship semi-finals into a family-orientated festival of football.




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Risk Factors for In-Hospital Mortality Among Children With Tuberculosis: The 25-Year Experience in Peru

Because most childhood tuberculosis cases are sputum smear-negative, diagnosis relies largely upon clinical presentation, tuberculin skin testing, and chest radiograph. Diagnostic limitations contribute to treatment delays and high mortality. However, childhood tuberculosis (TB) mortality risk factors are not well documented.

This study demonstrates that false-negative TST is common in children with active TB and is associated with increased risk of death. A negative TST should not delay anti-TB therapy. Improved diagnostic modalities are urgently needed in resource-limited settings. (Read the full article)




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Breastfeeding, Childhood Milk Consumption, and Onset of Puberty

Early life nutrition may program pubertal timing. Limited evidence suggests breastfeeding is associated with later puberty and childhood milk consumption with earlier puberty; whether these observations are biologically mediated or confounded by socioeconomic position is unclear.

In a developed non-Western setting with little socioeconomic patterning of pubertal timing, neither breastfeeding nor childhood milk consumption was associated with pubertal timing, suggesting nutritional exposures during potentially critical periods may not have long-term effects on rates of maturation. (Read the full article)




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Pediatric and Adolescent Tuberculosis in the United States, 2008-2010

Foreign-born children and adolescents in the United States experience higher tuberculosis (TB) morbidity rates than US-born children and adolescents. Pediatric risk assessment should account for country of birth, contact with a known TB case, or travel to TB-endemic countries.

Our study reports national data on parental/guardian countries of origin and international residence of pediatric patients with TB. Two-thirds of US-born children with TB have international family connections, and many have lived in countries with increased risk for TB acquisition. (Read the full article)




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Pediatric Tuberculosis at Beijing Children's Hospital: 2002-2010

Pediatric tuberculosis is significant for public health professionals because it is an indicator of the recent transmission of tuberculosis in the community. Data on incidence and clinical features of pediatric tuberculosis from China are scarce.

We conducted this study to describe the patient characteristics, clinical–epidemiological profile, and treatment outcomes for pediatric tuberculosis in a referral hospital setting in China. (Read the full article)




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Early Puberty, Negative Peer Influence, and Problem Behaviors in Adolescent Girls

Early timing of puberty and affiliation with deviant friends are associated with higher levels of delinquent and aggressive behavior. Early-maturing adolescents tend to affiliate with more-deviant peers and appear more susceptible to negative peer influences.

Young early-maturing girls do not yet associate with deviant friends but are more susceptible to negative peer influences. Early puberty effects are stable over time for delinquency but dissipate for aggression. Most of these relationships are invariant across race/ethnicity. (Read the full article)




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Epidemiology of Tuberculosis in Young Children in the United States

More than 60% of all US tuberculosis cases occur among foreign-born persons, but ~90% of cases in young children occur among US-born; many of these children have foreign-born parents, suggesting that this is an important population for prevention.

This is the first study to calculate tuberculosis rates in US-born children by parental nativity. Compared with US-born children with US-born parents, rates were 32 times higher in foreign-born children and 6 times higher in US-born children with foreign-born parents. (Read the full article)




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Impact of the FITKids Physical Activity Intervention on Adiposity in Prepubertal Children

Physical activity interventions aimed at improving body composition in childhood have had limited success and often targeted overweight children. Therefore, the efficacy of physical activity randomized controlled trials in improving body composition among children with varying adiposity levels remains unknown.

This randomized controlled trial demonstrated that a physical activity program designed to meet daily physical activity recommendations can improve cardiorespiratory fitness, decrease total fat mass, and prevent accumulation of central adiposity in a group of children with varying adiposity levels. (Read the full article)




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Cardiovascular Responses to Caffeine by Gender and Pubertal Stage

Caffeine has predictable effects on cardiovascular function in both adults and children. Our previous work has shown that there are gender differences in this cardiovascular response, with boys having a greater change in heart rate and blood pressure than girls.

This study shows that the gender differences in cardiovascular response to caffeine emerge after puberty and there are some differences in postpubertal girls across the menstrual cycle. (Read the full article)




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Young Adult Psychological Outcome After Puberty Suppression and Gender Reassignment

Puberty suppression has rapidly become part of the standard clinical management protocols for transgender adolescents. To date, there is only limited evidence for the long-term effectiveness of this approach after gender reassignment (cross-sex hormones and surgery).

In young adulthood, gender dysphoria had resolved, psychological functioning had steadily improved, and well-being was comparable to same-age peers. The clinical protocol including puberty suppression had provided these formerly gender-dysphoric youth the opportunity to develop into well-functioning young adults. (Read the full article)




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A Comparison of Interferon-{gamma} and IP-10 for the Diagnosis of Tuberculosis

IP-10 is a novel immunologic marker for tuberculosis (TB) infection. It has been suggested that IP-10 may perform better in children compared with the QuantiFERON test, but only a few studies have investigated IP-10 for diagnosing active TB in children.

This study is the first to investigate IP-10 and QuantiFERON for diagnosing TB in children by using consensus classifications. Both IP-10 and QuantiFERON exhibited poor performance in children from a high-burden setting, and performance was especially compromised in young children. (Read the full article)




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Validity of Self-Assessment of Pubertal Maturation

Many population-based studies including pubertal children are based on self-assessment of pubertal maturation, the reliability of which is uncertain.

Self-assessment is not reliable for precise pubertal staging. Simple distinctions between prepuberty and puberty showed moderate agreement with clinical examinations. Parents and girls tended to underestimate and boys to overestimate pubertal development by up to 50% and 30%, respectively. (Read the full article)




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Global and Regional Burden of Isoniazid-Resistant Tuberculosis

Fifteen percent of tuberculosis cases globally are resistant to the drug isoniazid. Isoniazid resistance puts patients with tuberculosis at risk for poor treatment outcomes and threatens the effectiveness of isoniazid preventive therapy in people with latent tuberculosis infection.

We present the first global and regional estimates of the proportion of children with tuberculosis who have isoniazid-resistant disease, showing large geographic variations in risk of resistance. We estimate the number of annual incident cases of isoniazid-resistant tuberculosis in children. (Read the full article)




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Risk Factors for Central Nervous System Tuberculosis

Central nervous system (CNS) tuberculosis has high morbidity and mortality, and it frequently affects children aged <5 years.

In California, children who were US-born, Hispanic, and aged <5 years were at increased risk of CNS tuberculosis. Children with CNS tuberculosis were more likely to die. Specific populations of US-born infants might benefit from additional prevention measures. (Read the full article)




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OPC-167832, a novel carbostyril derivative with potent anti-tuberculosis activity as a DprE1 inhibitor [Pharmacology]

There is an urgent need for new, potent anti-tuberculosis (TB) drugs with novel mechanisms of action that can be included in new regimens to shorten the treatment period for TB. After screening a library of carbostyrils, we optimized 3, 4-dihydrocarbostyril derivatives and identified OPC-167832 as having potent anti-tuberculosis activity. The minimum inhibitory concentrations of the compound for Mycobacterium tuberculosis ranged from 0.00024 to 0.002 μg/mL. It had bactericidal activity against both growing and intracellular bacilli, and the frequency of spontaneous resistance for Mycobacterium tuberculosis H37Rv was less than 1.91 x 10-7. It did not show antagonistic effects with other anti-TB agents in an in vitro checkerboard assay. Whole genome and targeted sequencing of resistant isolates to OPC-167832 identified the decaprenylphosphoryl-β-D-ribose 2'-oxidase (DprE1), an essential enzyme for cell wall biosynthesis, as the target of this compound, and further studies demonstrated inhibition of the DprE1 enzymatic activity by OPC-167832. In a mouse model of chronic TB, OPC-167832 showed potent bactericidal activities starting at a dose of 0.625 mg/kg. Further, it exhibited significant combination effects in 2-drug combinations with delamanid, bedaquiline, or levofloxacin. Finally, 3-4 drug regimens comprised of delamanid and OPC-167832 as the core along with bedaquiline, moxifloxacin, or linezolid showed superior efficacy in reducing bacterial burden and preventing relapse compared to the standard treatment regimen. In summary, these results suggest that OPC-167832 is a novel and potent anti-TB agent and regimens containing OPC-167832 and new or repurposed anti-TB drugs may have the potential to shorten the duration of treatment for TB.




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Genetic Mutations Associated with Isoniazid Resistance in Mycobacterium tuberculosis in Mongolia [Epidemiology and Surveillance]

Globally, mutations in the katG gene account for the majority of isoniazid-resistant strains of Mycobacterium tuberculosis. Buyankhishig et al analyzed a limited number of Mycobacterium tuberculosis strains in Mongolia and found that isoniazid resistance was mainly attributable to inhA mutations. The GenoType® MTBDRplus assay was performed for isolates collected in the First National Tuberculosis Prevalence Survey and the Third Anti-Tuberculosis Drug Resistance Survey to investigate genetic mutations associated with isoniazid resistance in Mycobacterium tuberculosis in Mongolia. Of the 409 isoniazid-resistant isolates detected by the GenoType® MTBDRplus assay, 127 (31.1%) were resistant to rifampicin, 294 (71.9%) had inhA mutations without katG mutations, 113 (27.6%) had katG mutations without inhA mutations, and two (0.5%) strains had mutations in both the inhA and katG genes. Of the 115 strains with any katG mutation, 114 (99.1%) had mutations in codon 315 (S315T). Of the 296 trains with any inhA mutation, 290 (98.0%) had a C–15T mutation. The proportion of isoniazid-resistant strains with katG mutations was 25.3% among new cases and 36.2% among retreatment cases (p=0.03), as well as 17.0% among rifampicin-susceptible strains and 52.8% among rifampicin-resistant strains (p<0.01). Rifampicin resistance was significantly associated with the katG mutation (adjusted odds ratio 5.36, 95% CI 3.3–8.67, p<0.001). Mutations in inhA predominated in isoniazid-resistant tuberculosis in Mongolia. However, the proportion of katG mutations in isolates from previously treated cases was higher than that among new cases, and that in cases with rifampicin resistance was higher than that in cases without rifampicin resistance.




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Advanced quantification methods to improve the 18b dormancy model for assessing the activity of tuberculosis drugs in vitro. [Clinical Therapeutics]

One of the reasons for the lengthy tuberculosis (TB) treatment is the difficult to treat non-multiplying mycobacterial subpopulation. In order to assess the ability of (new) TB drugs to target this subpopulation, we need to incorporate dormancy models in our pre-clinical drug development pipeline. In most available dormancy models it takes a long time to create a dormant state and it is difficult to identify and quantify this non-multiplying condition.

The Mycobacterium tuberculosis 18b strain might overcome some of these problems, because it is dependent on streptomycin for growth and becomes non-multiplying after 10 days of streptomycin starvation, but still can be cultured on streptomycin-supplemented culture plates. We developed our 18b dormancy time-kill kinetic model to assess the difference in the activity of isoniazid, rifampicin, moxifloxacin and bedaquiline against log-phase growth compared to the non-multiplying M. tuberculosis subpopulation by CFU counting including a novel AUC-based approach as well as time-to-positivity (TTP) measurements.

We observed that isoniazid and moxifloxacin were relatively more potent against replicating bacteria, while rifampicin and high dose bedaquiline were equally effective against both subpopulations. Moreover, the TTP data suggest that including a liquid culture-based method could be of additional value as it identifies a specific mycobacterial subpopulation that is non-culturable on solid media.

In conclusion, the results of our study underline that the time-kill kinetics 18b dormancy model in its current form is a useful tool to assess TB drug potency and thus has its place in the TB drug development pipeline.




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Optimal dose or optimal exposure? Consideration for linezolid in tuberculosis treatment [Letters]

Exploring different ways of minimising linezolid toxicity without compromising efficacy is a major quest in the treatment of drug resistant tuberculosis (TB)....




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Distribution of linezolid in tuberculosis lesions in patients with spinal multidrug-resistant tuberculosis [Pharmacology]

Linezolid has strong antimicrobial activity against the multidrug-resistant (MDR) strains of Mycobacterium tuberculosis. Little is known about the distribution of linezolid in tuberculosis (TB) lesions in patients with MDR-TB. The aim of this study is to evaluate the distribution of linezolid in TB lesions in patients with spinal MDR-TB. Nine patients with spinal MDR-TB were enrolled prospectively from August 2019 to February 2020. The patients received a linezolid-containing anti-TB treatment regimen and needed surgery for the removal of TB lesions. During the operation, nine blood samples, eight diseased bone tissue samples, seven pus samples and four granulation tissue samples were collected simultaneously and 2 h after the oral administration of 600 mg of linezolid. Linezolid concentrations in plasma, diseased bone tissue, pus, and granulation tissue samples were subjected to high-performance liquid chromatography–tandem mass spectrometry. At sample collection, the mean concentrations of linezolid in plasma, diseased bone tissue, pus, and granulation tissue samples of the nine patients were 11.14 ± 5.82, 5.94 ± 4.27, 11.09 ± 4.58, 14.08 ± 10.61 mg/L, respectively. The mean ratios of linezolid concentration in diseased bone/plasma, pus/plasma, and granulation/plasma were 53.84%, 91.69%, and 103.57%, respectively. The mean ratios of linezolid concentration in pus/plasma and granulation/plasma were higher than those in diseased bone/plasma, and the difference was statistically significant (t =-2.810, p = 0.015; t =-4.901, p = 0.001). In conclusion, linezolid had different concentration distributions in different types of TB infected tissues in patients with spinal MDR-TB.




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Reply to Kim et al., "Optimal Dose or Optimal Exposure? Consideration for Linezolid in Tuberculosis Treatment" [Author Reply]

We thank Kim and colleagues for their interest in our study....




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The Efficacy of Bacillus Calmette-Guerin Vaccination of Newborns and Infants in the Prevention of Tuberculosis: Meta-Analyses of the Published Literature

Graham A. Colditz
Jul 1, 1995; 96:29-35
ARTICLES




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COVID-19: Uber India to offer free rides to healthcare workers, govt officials of Chennai Corporation

To ensure hygiene while transporting, the drivers of UberMedic were trained in safety procedures and also provided with personal protective equipment and disinfectants, it said.




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The truly autonomous car is here: Volvo, Uber unveil production ready self-driving vehicle

The Volvo XC90 SUV presented this week is the first production car that in combination with Uber’s self-driving system is capable of fully driving itself.




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Formula 1 Racing: F1 is safer than ever, Anthoine Hubert’s was one of case

During the 1950s and 1960s, Formula racing lost more drivers than the next three decades. Instead, in the 1980s, accident-related deaths were four, which is still higher than the last three decades of Formula racing.




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Uber scraps post-trip tracking feature via app; how empowering was that? Find out

Uber doing away with the post-trip tracking feature that had drawn the ire of users is a sign of the torsion privacy concerns create when faced with the demands of a data-driven world.




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Lyft to woo investors with fast US growth in IPO race with Uber

Lyft will pitch investors on its fast growth in the United States as it seeks to beat out Uber to become the first publicly listed ride-hailing company, according to people familiar with the matter.




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Uber resumes operations in green, orange zones amid lockdown

In a bid to curb the transmission of novel Coronavirus, India suspended public transport services and enforced a nearly two-month country-wide lockdown that is currently set to end on May 17.




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Uber ડ્રાઇવરે યુવતીને સંભળવાવ્યું સુરીલું ગીત, ઇન્ટરનેટ પર વીડિયો થયો વાયરલ

ઉબર ડ્રાઇવરના વાયરલ વીડિયોને 50 હજારથી વ્યૂ મળી ચૂક્યા છે, આ કારણે આવી રહ્યો છે પસંદ




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দেশের অন্যতম সেরা ই-হেলথ প্ল্যাটফর্মের সঙ্গে গাঁটছড়া, লকডাউনে বাড়ি বাড়ি ওষুধ পৌঁছে দিচ্ছে Uber





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Uber lays off 40% of Cairo office, largest in Middle East

The layoffs come amid global cuts as the coronavirus pandemic sees revenues drop.




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Tuberculosis BCG vaccine gets into global Covid-19 trial

South Africa vaccinates health workers in response to the pandemic.




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Millions at risk of tuberculosis amid COVID-19 lockdowns, warns study

1





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After being kidnapped and threatened, Mozambican YouTuber has his channel suspended

In early February, he was kidnapped for 24 hours, before he was freed by the police. A self-proclaimed prophet named Joe Williams is suspected of ordering the kidnapping.




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Venture firm Benchmark raises new fund without early Uber investor: source

The Silicon Valley venture capital firm known for its early backing of companies such as Uber Technologies Inc is raising a new fund, but without one of its most prominent general partners, a source...




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Peptidoglycan Hydrolases RipA and Ami1 Are Critical for Replication and Persistence of Mycobacterium tuberculosis in the Host

ABSTRACT

Synthesis and cleavage of the cell wall polymer peptidoglycan (PG) are carefully orchestrated processes and are essential for the growth and survival of bacteria. Yet, the function and importance of many enzymes that act on PG in Mycobacterium tuberculosis remain to be elucidated. We demonstrate that the activity of the N-acetylmuramyl-l-alanine amidase Ami1 is dispensable for cell division in M. tuberculosis in vitro yet contributes to the bacterium’s ability to persist during chronic infection in mice. Furthermore, the d,l-endopeptidase RipA, a predicted essential enzyme, is dispensable for the viability of M. tuberculosis but required for efficient cell division in vitro and in vivo. Depletion of RipA sensitizes M. tuberculosis to rifampin and to cell envelope-targeting antibiotics. Ami1 helps sustain residual cell division in cells lacking RipA, but the partial redundancy provided by Ami1 is not sufficient during infection, as depletion of RipA prevents M. tuberculosis from replicating in macrophages and leads to dramatic killing of the bacteria in mice. Notably, RipA is essential for persistence of M. tuberculosis in mice, suggesting that cell division is required during chronic mouse infection. Despite the multiplicity of enzymes acting on PG with redundant functions, we have identified two PG hydrolases that are important for M. tuberculosis to replicate and persist in the host.

IMPORTANCE Tuberculosis (TB) is a major global heath burden, with 1.6 million people succumbing to the disease every year. The search for new drugs to improve the current chemotherapeutic regimen is crucial to reducing this global health burden. The cell wall polymer peptidoglycan (PG) has emerged as a very successful drug target in bacterial pathogens, as many currently used antibiotics target the synthesis of this macromolecule. However, the multitude of genes encoding PG-synthesizing and PG-modifying enzymes with apparent redundant functions has hindered the identification of novel drug targets in PG synthesis in Mycobacterium tuberculosis. Here, we demonstrate that two PG-cleaving enzymes are important for virulence of M. tuberculosis. In particular, the d,l-endopeptidase RipA represents a potentially attractive drug target, as its depletion results in the clearance of M. tuberculosis from the host and renders the bacteria hypersusceptible to rifampin, a frontline TB drug, and to several cell wall-targeting antibiotics.




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Mycobacterium tuberculosis Reactivates HIV-1 via Exosome-Mediated Resetting of Cellular Redox Potential and Bioenergetics

ABSTRACT

The synergy between Mycobacterium tuberculosis and human immunodeficiency virus-1 (HIV-1) interferes with therapy and facilitates the pathogenesis of both human pathogens. Fundamental mechanisms by which M. tuberculosis exacerbates HIV-1 infection are not clear. Here, we show that exosomes secreted by macrophages infected with M. tuberculosis, including drug-resistant clinical strains, reactivated HIV-1 by inducing oxidative stress. Mechanistically, M. tuberculosis-specific exosomes realigned mitochondrial and nonmitochondrial oxygen consumption rates (OCR) and modulated the expression of host genes mediating oxidative stress response, inflammation, and HIV-1 transactivation. Proteomics analyses revealed the enrichment of several host factors (e.g., HIF-1α, galectins, and Hsp90) known to promote HIV-1 reactivation in M. tuberculosis-specific exosomes. Treatment with a known antioxidant—N-acetyl cysteine (NAC)—or with inhibitors of host factors—galectins and Hsp90—attenuated HIV-1 reactivation by M. tuberculosis-specific exosomes. Our findings uncover new paradigms for understanding the redox and bioenergetics bases of HIV-M. tuberculosis coinfection, which will enable the design of effective therapeutic strategies.

IMPORTANCE Globally, individuals coinfected with the AIDS virus (HIV-1) and with M. tuberculosis (causative agent of tuberculosis [TB]) pose major obstacles in the clinical management of both diseases. At the heart of this issue is the apparent synergy between the two human pathogens. On the one hand, mechanisms induced by HIV-1 for reactivation of TB in AIDS patients are well characterized. On the other hand, while clinical findings clearly identified TB as a risk factor for HIV-1 reactivation and associated mortality, basic mechanisms by which M. tuberculosis exacerbates HIV-1 replication and infection remain poorly characterized. The significance of our research is in identifying the role of fundamental mechanisms such as redox and energy metabolism in catalyzing HIV-M. tuberculosis synergy. The quantification of redox and respiratory parameters affected by M. tuberculosis in stimulating HIV-1 will greatly enhance our understanding of HIV-M. tuberculosis coinfection, leading to a wider impact on the biomedical research community and creating new translational opportunities.




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Erratum for Dai et al., "Autoantibody-Mediated Erythrophagocytosis Increases Tuberculosis Susceptibility in HIV Patients"




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Ahmed A, Fend PI, Gaensbauer JT, Reves RR, Khurana R, Salcedo K, Punnoose R, Katz DJ, for the TUBERCULOSIS EPIDEMIOLOGIC STUDIES CONSORTIUM. Interferon-{gamma} Release Assays in Children <15 Years of Age. Pediatrics. 2020:145(1):e20191930




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A single amino acid substitution uncouples catalysis and allostery in an essential biosynthetic enzyme in Mycobacterium tuberculosis [Enzymology]

Allostery exploits the conformational dynamics of enzymes by triggering a shift in population ensembles toward functionally distinct conformational or dynamic states. Allostery extensively regulates the activities of key enzymes within biosynthetic pathways to meet metabolic demand for their end products. Here, we have examined a critical enzyme, 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (DAH7PS), at the gateway to aromatic amino acid biosynthesis in Mycobacterium tuberculosis, which shows extremely complex dynamic allostery: three distinct aromatic amino acids jointly communicate occupancy to the active site via subtle changes in dynamics, enabling exquisite fine-tuning of delivery of these essential metabolites. Furthermore, this allosteric mechanism is co-opted by pathway branchpoint enzyme chorismate mutase upon complex formation. In this study, using statistical coupling analysis, site-directed mutagenesis, isothermal calorimetry, small-angle X-ray scattering, and X-ray crystallography analyses, we have pinpointed a critical node within the complex dynamic communication network responsible for this sophisticated allosteric machinery. Through a facile Gly to Pro substitution, we have altered backbone dynamics, completely severing the allosteric signal yet remarkably, generating a nonallosteric enzyme that retains full catalytic activity. We also identified a second residue of prime importance to the inter-enzyme communication with chorismate mutase. Our results reveal that highly complex dynamic allostery is surprisingly vulnerable and provide further insights into the intimate link between catalysis and allostery.




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Identification of Novel Antigens Recognized by Serum Antibodies in Bovine Tuberculosis [Diagnostic Laboratory Immunology]

Bovine tuberculosis (TB), caused by Mycobacterium bovis, remains an important zoonotic disease posing a serious threat to livestock and wildlife. The current TB tests relying on cell-mediated and humoral immune responses in cattle have performance limitations. To identify new serodiagnostic markers of bovine TB, we screened a panel of 101 recombinant proteins, including 10 polyepitope fusions, by a multiantigen print immunoassay (MAPIA) with well-characterized serum samples serially collected from cattle with experimental or naturally acquired M. bovis infection. A novel set of 12 seroreactive antigens was established. Evaluation of selected proteins in the dual-path platform (DPP) assay showed that the highest diagnostic accuracy (~95%) was achieved with a cocktail of five best-performing antigens, thus demonstrating the potential for development of an improved and more practical serodiagnostic test for bovine TB.




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GI-19007, a Novel Saccharomyces cerevisiae-Based Therapeutic Vaccine against Tuberculosis [Vaccines]

As yet, very few vaccine candidates with activity in animals against Mycobacterium tuberculosis infection have been tested as therapeutic postexposure vaccines. We recently described two pools of mycobacterial proteins with this activity, and here we describe further studies in which four of these proteins (Rv1738, Rv2032, Rv3130, and Rv3841) were generated as a fusion polypeptide and then delivered in a novel yeast-based platform (Tarmogen) which itself has immunostimulatory properties, including activation of Toll-like receptors. This platform can deliver antigens into both the class I and class II antigen presentation pathways and stimulate strong Th1 and Th17 responses. In mice this fusion vaccine, designated GI-19007, was immunogenic and elicited strong gamma interferon (IFN-) and interleukin-17 (IL-17) responses; despite this, they displayed minimal prophylactic activity in mice that were subsequently infected with a virulent clinical strain. In contrast, in a therapeutic model in the guinea pig, GI-19007 significantly reduced the lung bacterial load and reduced lung pathology, particularly in terms of secondary lesion development, while significantly improving survival in one-third of these animals. In further studies in which guinea pigs were vaccinated with BCG before challenge, therapeutic vaccination with GI-19007 initially improved survival versus that of animals given BCG alone, although this protective effect was gradually lost at around 400 days after challenge. Given its apparent ability to substantially limit bacterial dissemination within and from the lungs, GI-19007 potentially can be used to limit lung damage as well as facilitating chemotherapeutic regimens in infected individuals.




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Mobilising community networks for early identification of tuberculosis and treatment initiation in Cambodia: an evaluation of a seed-and-recruit model

Background and objectives

The effects of active case finding (ACF) models that mobilise community networks for early identification and treatment of tuberculosis (TB) remain unknown. We investigated and compared the effect of community-based ACF using a seed-and-recruit model with one-off roving ACF and passive case finding (PCF) on the time to treatment initiation and identification of bacteriologically confirmed TB.

Methods

In this retrospective cohort study conducted in 12 operational districts in Cambodia, we assessed relationships between ACF models and: 1) the time to treatment initiation using Cox proportional hazards regression; and 2) the identification of bacteriologically confirmed TB using modified Poisson regression with robust sandwich variance.

Results

We included 728 adults with TB, of whom 36% were identified via the community-based ACF using a seed-and-recruit model. We found community-based ACF using a seed-and-recruit model was associated with shorter delay to treatment initiation compared to one-off roving ACF (hazard ratio 0.81, 95% CI 0.68–0.96). Compared to one-off roving ACF and PCF, community-based ACF using a seed-and-recruit model was 45% (prevalence ratio (PR) 1.45, 95% CI 1.19–1.78) and 39% (PR 1.39, 95% CI 0.99–1.94) more likely to find and detect bacteriologically confirmed TB, respectively.

Conclusion

Mobilising community networks to find TB cases was associated with early initiation of TB treatment in Cambodia. This approach was more likely to find bacteriologically confirmed TB cases, contributing to the reduction of risk of transmission within the community.




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The Bewildering Antitubercular Action of Pyrazinamide [Review]

Pyrazinamide (PZA) is a cornerstone antimicrobial drug used exclusively for the treatment of tuberculosis (TB). Due to its ability to shorten drug therapy by 3 months and reduce disease relapse rates, PZA is considered an irreplaceable component of standard first-line short-course therapy for drug-susceptible TB and second-line treatment regimens for multidrug-resistant TB. Despite over 60 years of research on PZA and its crucial role in current and future TB treatment regimens, the mode of action of this unique drug remains unclear. Defining the mode of action for PZA will open new avenues for rational design of novel therapeutic approaches for the treatment of TB. In this review, we discuss the four prevailing models for PZA action, recent developments in modulation of PZA susceptibility and resistance, and outlooks for future research and drug development.