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1.
Front Mol Biosci ; 11: 1342011, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38375508

RESUMEN

Reprogramming human somatic cells into a pluripotent state, achieved through the activation of well-defined transcriptional factors known as OSKM factors, offers significant potential for regenerative medicine. While OSKM factors are a robust reprogramming method, efficiency remains a challenge, with only a fraction of cells undergoing successful reprogramming. To address this, we explored genes related to genomic integrity and cellular survival, focusing on iPSCs (A53T-PD1) that displayed enhanced colony stability. Our investigation had revealed three candidate genes CCN3, POSTN, and PTHLH that exhibited differential expression levels and potential roles in iPSC stability. Subsequent analyses identified various protein interactions for these candidate genes. POSTN, significantly upregulated in A53T-PD1 iPSC line, showed interactions with extracellular matrix components and potential involvement in Wnt signaling. CCN3, also highly upregulated, demonstrated interactions with TP53, CDKN1A, and factors related to apoptosis and proliferation. PTHLH, while upregulated, exhibited interactions with CDK2 and genes involved in cell cycle regulation. RT-qPCR validation confirmed elevated CCN3 and PTHLH expression in A53T-PD1 iPSCs, aligning with RNA-seq findings. These genes' roles in preserving pluripotency and cellular stability require further exploration. In conclusion, we identified CCN3, POSTN, and PTHLH as potential contributors to genomic integrity and pluripotency maintenance in iPSCs. Their roles in DNA repair, apoptosis evasion, and signaling pathways could offer valuable insights for enhancing reprogramming efficiency and sustaining pluripotency. Further investigations are essential to unravel the mechanisms underlying their actions.

2.
Front Immunol ; 14: 1146443, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37122708

RESUMEN

Background: The cross-protective nature of Bacillus Calmette-Guerin (BCG) vaccine against SARS-CoV-2 virus was previously suggested, however its effect in COVID-19 patients with type 2 diabetes (T2D) and the underlying metabolic pathways has not been addressed. This study aims to investigate the difference in the metabolomic patterns of type 2 diabetic patients with BCG vaccination showing different severity levels of COVID-19 infection. Methods: Sixty-seven COVID-19 patients were categorized into diabetic and non-diabetic individuals who had been previously vaccinated or not with BCG vaccination. Targeted metabolomics were performed from serum samples from all patients using tandem mass spectrometry. Statistical analysis included multivariate and univariate models. Results: Data suggested that while BCG vaccination may provide protection for individuals who do not have diabetes, it appears to be linked to more severe COVID-19 symptoms in T2D patients (p = 0.02). Comparing the metabolic signature of BCG vaccinated T2D individuals to non-vaccinated counterparts revealed that amino acid (sarcosine), cholesterol esters (CE 20:0, 20:1, 22:2), carboxylic acid (Aconitic acid) were enriched in BCG vaccinated T2D patients, whereas spermidine, glycosylceramides (Hex3Cer(d18:1_22:0), Hex2Cer(d18:1/22:0), HexCer(d18:1/26:1), Hex2Cer(d18:1/24:0), HexCer(d18:1/22:0) were higher in BCG vaccinated non- T2D patients. Furthermore, data indicated a decrease in sarcosine synthesis from glycine and choline and increase in spermidine synthesis in the BCG vaccinated cohort in T2D and non-T2D groups, respectively. Conclusion: This pilot study suggests increased severity of COVID-19 in BCG vaccinated T2D patients, which was marked by decreased sarcosine synthesis, perhaps via lower sarcosine-mediated removal of viral antigens.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Vacuna BCG , Estudios Retrospectivos , SARS-CoV-2 , Vacunas contra la COVID-19 , Proyectos Piloto , Sarcosina , Espermidina , Vacunación/métodos
3.
Ann Med Surg (Lond) ; 85(5): 1590-1593, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37228930

RESUMEN

Mycetoma is a chronic specific granulomatous progressive and disfiguring subcutaneous inflammatory disease. It is caused by true fungi (Eumycetoma) or by higher bacteria (actinomycetoma). Mycetoma mainly affects the lower limbs, followed by the upper limbs, back, and rarely the head and neck. Mycetoma is mainly transmitted through trauma with infected sharp objects. Herein, we want to determine the neurological manifestations of mycetoma in Sudanese patients. Methodology: A descriptive cross-sectional community-based study included 160 patients with mycetoma seen in the White Nile state. A team of doctors collected data using standardized questionnaires that included clinical history, neurological examination, investigations including laboratory, neurophysiological studies, and imaging. Results: Almost 160 patients were included in the study; 90% of them were male. Two patients presented with entrapment neuropathy, one presented with proximal neuropathy, one had peripheral neuropathy, one had dorsal spine involvement and presented with spastic paraplegia with sensory level, one had cervical cord compression, and one patient had repeated attacks of convulsion. Conclusion: Although it is rare, clinicians should highly suspect neurological involvement in mycetoma patients.

4.
Ann Med Surg (Lond) ; 82: 104653, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36268312

RESUMEN

Introduction: As it is a disseminated disease, HIV infection can be associated with significant cardiovascular and neurological complications; however, this commonly occurs late. Here, we highlight the unusual initial presentation of HIV infection, which is myocardial infarction complicated by stroke. Case presentation: A 30 years old male with a clear medical background presented with severe chest pain with evidence of ischemia on ECG and positive serum troponin. he received anti-ischemic drugs, and was prepared for coronary angiography with routine investigations tested positive for HIV; however, his condition was later complicated by stroke. Discussion: Antiretroviral medication, HIV disease characteristics, female gender, and HCV co-infection are risk factors for coronary artery disease (CAD) in HIV patients. Patients living with HIV are also at risk of developing stroke, which can be caused by atherosclerosis of the major arteries, small artery disease, cardiac embolism, CNS infections, coagulation issues, and non-atherosclerotic vasculopathy. Conclusion: The presentation of an acute coronary syndrome in a young patient should raise suspicion of uncommon causes and needs a prompt evaluation from digging up in history, detailed examination, and investigations with close follow-up to prevent the complications that may occur. on the other hand, known HIV Patients should be screened periodically with an electrocardiogram.

5.
Ann Med Surg (Lond) ; 82: 104712, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36268419

RESUMEN

Background: Epilepsy can be associated with functional seizures. Our main aim is to assess functional seizures' prevalence and risk factors among adult Sudanese patients with epilepsy. Methods: This cross-sectional clinic-based study was conducted from January to February 2021 at Daoud Charity Clinic in Omdurman city, Sudan. Ninety-nine adult Sudanese patients with epilepsy were included. Data were collected using a validated interview-based semi-structured questionnaire. A senior consultant neurologist and a consultant psychiatrist diagnosed the functional seizures based on full clinical history and investigations. The diagnosis was performed according to International League against epilepsy (ILAE) classification. Results: This study included 99 patients with epilepsy, 57% were females, 79% reside in Khartoum state, and 32% reached secondary school. The main types of epilepsy were generalized tonic-clonic (68%), followed by focal seizures with impaired awareness (11%). The majority of the patients have been diagnosed with epilepsy for over three years (65%). Comorbid epilepsy and functional seizures were found in 29% of the patients, with a significantly higher prevalence in patients with social problems and depression (p = 0.005 and p < 0.01, respectively). Patients with depression had a 14 times higher risk of functional seizures than those without depression, 95% CI [3.8, 52.3]. Conclusion: A remarkably high prevalence of functional seizures was found among adult patients with epilepsy. Patients suffering from social problems and/or depression and poor economic status had a higher tendency to develop functional seizures, especially after two to three years of treatment and above.

6.
Front Cell Infect Microbiol ; 12: 929689, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937683

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection currently remains one of the biggest global challenges that can lead to acute respiratory distress syndrome (CARDS) in severe cases. In line with this, prior pulmonary tuberculosis (TB) is a risk factor for long-term respiratory impairment. Post-TB lung dysfunction often goes unrecognized, despite its relatively high prevalence and its association with reduced quality of life. In this study, we used a metabolomics analysis to identify potential biomarkers that aid in the prognosis of COVID-19 morbidity and mortality in post-TB infected patients. This analysis involved blood samples from 155 SARS-CoV-2 infected adults, of which 23 had a previous diagnosis of TB (post-TB), while 132 did not have a prior or current TB infection. Our analysis indicated that the vast majority (~92%) of post-TB individuals showed severe SARS-CoV-2 infection, required intensive oxygen support with a significantly high mortality rate (52.2%). Amongst individuals with severe COVID-19 symptoms, we report a significant decline in the levels of amino acids, notably the branched chains amino acids (BCAAs), more so in the post-TB cohort (FDR <= 0.05) in comparison to mild and asymptomatic cases. Indeed, we identified betaine and BCAAs as potential prognostic metabolic biomarkers of severity and mortality, respectively, in COVID-19 patients who have been exposed to TB. Moreover, we identified serum alanine as an important metabolite at the interface of severity and mortality. Hence, our data associated COVID-19 mortality and morbidity with a long-term metabolically driven consequence of TB infection. In summary, our study provides evidence for a higher mortality rate among COVID-19 infection patients who have history of prior TB infection diagnosis, which mandates validation in larger population cohorts.


Asunto(s)
COVID-19 , Tuberculosis , Adulto , Alanina , Humanos , Morbilidad , Pronóstico , Calidad de Vida , SARS-CoV-2 , Tuberculosis/complicaciones , Tuberculosis/diagnóstico , Tuberculosis/epidemiología
7.
Arch Virol ; 167(9): 1773-1783, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35723757

RESUMEN

Currently, health authorities around the world are struggling to limit the spread of COVID-19. Since the beginning of the pandemic, social distancing has been the most important strategy used by most countries to control disease spread by flattening and elongating the epidemic curve. Another strategy, herd immunity, was also applied by some countries through relaxed control measures that allow the free spread of natural infection to build up solid immunity within the population. In 2021, COVID-19 vaccination was introduced with tremendous effort as a promising strategy for limiting the spread of disease. Therefore, in this review, we present the current knowledge about social distancing, herd immunity strategies, and aspects of their implementation to control the COVID-19 pandemic in the presence of the newly developed vaccines. Finally, we suggest a short-term option for controlling the pandemic during vaccine application.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunidad Colectiva , Pandemias/prevención & control , Distanciamiento Físico , SARS-CoV-2
8.
J Med Virol ; 94(8): 3685-3697, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35415939

RESUMEN

Malaria and coronavirus disease 2019 (COVID-19) share several characteristics that could lead to cross-infection, particularly in malaria-endemic areas. Early COVID-19 symptoms might be misdiagnosed for malaria in clinical settings. Also, both diseases can cause fatal complications. So, laboratory testing for both diseases was recommended by the World Health Organization. To study the clinical characteristics and outcomes of Adult Sudanese patients with COVID-19 and malaria coinfection. This retrospective cross-sectional study was conducted from January 2021 to October 2021 in Wad Medani. Total coverage of all Sudanese patients above 18 years old with a confirmed diagnosis of coinfection with COVID-19 and malaria was included, and data were collected using a data collection sheet. Data were analyzed using R software version 4.0.2. Data were described and presented as mean, standard deviation, and number (percentage). To find associated factors with in-hospital outcome, χ2 test, fisher exact test, and independent t test or Wilcoxon rank-sum test were used. In this study, 156 participants were diagnosed with COVID-19 and malaria coinfection. Most of them were between 60 and 70 years (30.8%), the majority were males (59%). Shortness of breath (76.3%) and acute respiratory distress syndrome (35.3%) were the most common symptom and complications among coinfected patients, respectively. Ground glass opacity (n = 47/49, 95.9%) is the most common result for computed tomography scan. Atrial fibrillation was the most common abnormal electrocardiogram finding (n = 6/62, 9.7%). Overall mortality among all participants was (63/156, 40.4%). High mortality rate was found among the coinfected patients. More attention is needed towards fighting COVID-19 and malaria coinfection. There may be a link between malaria and COVID-19.


Asunto(s)
COVID-19 , Coinfección , Malaria , Adolescente , Adulto , COVID-19/complicaciones , COVID-19/diagnóstico , Coinfección/epidemiología , Estudios Transversales , Femenino , Humanos , Malaria/complicaciones , Malaria/diagnóstico , Malaria/epidemiología , Masculino , Estudios Retrospectivos , Sudán/epidemiología
9.
Front Med (Lausanne) ; 8: 788687, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35083246

RESUMEN

Introduction: Increased COVID-19 disease severity is higher among patients with type 2 diabetes mellitus and hypertension. However, the metabolic pathways underlying this association are not fully characterized. This study aims to identify the metabolic signature associated with increased COVID-19 severity in patients with diabetes mellitus and hypertension. Methods: One hundred and fifteen COVID-19 patients were divided based on disease severity, diabetes status, and hypertension status. Targeted metabolomics of serum samples from all patients was performed using tandem mass spectrometry followed by multivariate and univariate models. Results: Reduced levels of various triacylglycerols were observed with increased disease severity in the diabetic patients, including those containing palmitic (C16:0), docosapentaenoic (C22:5, DPA), and docosahexaenoic (C22:6, DHA) acids (FDR < 0.01). Functional enrichment analysis revealed triacylglycerols as the pathway exhibiting the most significant changes in severe COVID-19 in diabetic patients (FDR = 7.1 × 10-27). Similarly, reduced levels of various triacylglycerols were also observed in hypertensive patients corresponding with increased disease severity, including those containing palmitic, oleic (C18:1), and docosahexaenoic acids. Functional enrichment analysis revealed long-chain polyunsaturated fatty acids (n-3 and n-6) as the pathway exhibiting the most significant changes with increased disease severity in hypertensive patients (FDR = 0.07). Conclusions: Reduced levels of triacylglycerols containing specific long-chain unsaturated, monounsaturated, and polyunsaturated fatty acids are associated with increased COVID-19 severity in diabetic and hypertensive patients, offering potential novel diagnostic and therapeutic targets.

10.
BMC Med Genomics ; 13(1): 103, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32680510

RESUMEN

BACKGROUND: Testing strategies is crucial for genetics clinics and testing laboratories. In this study, we tried to compare the hit rate between solo and trio and trio plus testing and between trio and sibship testing. Finally, we studied the impact of extended family analysis, mainly in complex and unsolved cases. METHODS: Three cohorts were used for this analysis: one cohort to assess the hit rate between solo, trio and trio plus testing, another cohort to examine the impact of the testing strategy of sibship genome vs trio-based analysis, and a third cohort to test the impact of an extended family analysis of up to eight family members to lower the number of candidate variants. RESULTS: The hit rates in solo, trio and trio plus testing were 39, 40, and 41%, respectively. The total number of candidate variants in the sibship testing strategy was 117 variants compared to 59 variants in the trio-based analysis. We noticed that the average number of coding candidate variants in trio-based analysis was 1192 variants and 26,454 noncoding variants, and this number was lowered by 50-75% after adding additional family members, with up to two coding and 66 noncoding homozygous variants only, in families with eight family members. CONCLUSION: There was no difference in the hit rate between solo and extended family members. Trio-based analysis was a better approach than sibship testing, even in a consanguineous population. Finally, each additional family member helped to narrow down the number of variants by 50-75%. Our findings could help clinicians, researchers and testing laboratories select the most cost-effective and appropriate sequencing approach for their patients. Furthermore, using extended family analysis is a very useful tool for complex cases with novel genes.


Asunto(s)
Consanguinidad , Exoma , Familia , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Variación Genética , Adulto , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Secuenciación del Exoma
11.
Artículo en Inglés | MEDLINE | ID: mdl-32266172

RESUMEN

Mycobacterium kansasii is an important opportunistic pathogen of humans and has a close phylogenetic relationship with Mycobacterium tuberculosis. Seven subtypes (I-VII) have been identified using molecular biology approaches, of which subtype I is the most frequent causative agent of human disease. To investigate the genotypes and pathogenic components of M. kansasii, we sequenced and compared the complete base-perfect genomes of different M. kansasii subtypes. Our findings support the proposition that M. kansasii "subtypes" I-VI, whose assemblies are currently available, should be considered as different species. Furthermore, we identified the exclusive presence of the espACD operon in M. kansasii subtype I, and we confirmed its role in the pathogenicity of M. kansasii in a cell infection model. The espACD operon is exclusively present in mycobacterial species that induce phagosomal rupture in host phagocytes and is known to be a major determinant of ESX1-mediated virulence in pathogenic mycobacteria. Comparative transcriptome analysis of the M. kansasii I-V strains identified genes potentially associated with virulence. Using a comparative genomics approach, we designed primers for PCR genotyping of M. kansasii subtypes I-V and tested their efficacy using clinically relevant strains of M. kansasii.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Mycobacterium kansasii , Perfilación de la Expresión Génica , Genómica , Humanos , Mycobacterium kansasii/genética , Filogenia , Transcriptoma , Virulencia
12.
Mol Microbiol ; 112(1): 81-98, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30983025

RESUMEN

Disarming pathogens by targeting virulence factors is a promising alternative to classic antibiotics. Many virulence factors in Gram-negative bacteria are secreted via the autotransporter (AT) pathway, also known as Type 5 secretion. These factors are secreted with the assistance of two membrane-based protein complexes: Sec and Bam. To identify inhibitors of the AT pathway, we used transcriptomics analysis to develop a fluorescence-based high-throughput assay that reports on the stress induced by the model AT hemoglobin protease (Hbp) when its secretion across the outer membrane is inhibited. Screening a library of 1600 fragments yielded the compound VUF15259 that provokes cell envelope stress and secretion inhibition of the ATs Hbp and Antigen-43. VUF15259 also impairs ß-barrel folding activity of various outer membrane proteins. Furthermore, we found that mutants that are compromised in outer membrane protein biogenesis are more susceptible to VUF15259. Finally, VUF15259 induces the release of vesicles that appear to assemble in short chains. Taken together, VUF15259 is the first reported compound that inhibits AT secretion and our data are mostly consistent with VUF15259 interfering with the Bam-complex as potential mode of action. The validation of the presented assay incites its use to screen larger compound libraries with drug-like compounds.


Asunto(s)
Sistemas de Secreción Tipo V/antagonistas & inhibidores , Sistemas de Secreción Tipo V/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Endopeptidasas/metabolismo , Bacterias Gramnegativas , Proteínas de Transporte de Membrana/metabolismo , Modelos Moleculares , Pliegue de Proteína , Estructura Terciaria de Proteína , Transporte de Proteínas/fisiología , Canales de Translocación SEC/antagonistas & inhibidores , Canales de Translocación SEC/metabolismo , Factores de Virulencia/metabolismo
13.
PLoS One ; 14(1): e0211003, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30673778

RESUMEN

The mycobacterial type VII secretion system ESX-1 is responsible for the secretion of a number of proteins that play important roles during host infection. The regulation of the expression of secreted proteins is often essential to establish successful infection. Using transcriptome sequencing, we found that the abrogation of ESX-1 function in Mycobacterium marinum leads to a pronounced increase in gene expression levels of the espA operon during the infection of macrophages. In addition, the disruption of ESX-1-mediated protein secretion also leads to a specific down-regulation of the ESX-1 substrates, but not of the structural components of this system, during growth in culture medium. This effect is observed in both M. marinum and M. tuberculosis. We established that down-regulation of ESX-1 substrates is the result of a regulatory process that is influenced by the putative transcriptional regulator whib6, which is located adjacent to the esx-1 locus. In addition, the overexpression of the ESX-1-associated PE35/PPE68 protein pair resulted in a significantly increased secretion of the ESX-1 substrate EsxA, demonstrating a functional link between these proteins. Taken together, these data show that WhiB6 is required for the secretion-dependent regulation of ESX-1 substrates and that ESX-1 substrates are regulated independently from the structural components, both during infection and as a result of active secretion.


Asunto(s)
Antígenos Bacterianos , Proteínas Bacterianas , Regulación hacia Abajo , Regulación Bacteriana de la Expresión Génica , Mycobacterium marinum , Mycobacterium tuberculosis , Transcriptoma , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Humanos , Mutación , Mycobacterium marinum/genética , Mycobacterium marinum/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Células THP-1
14.
Artículo en Inglés | MEDLINE | ID: mdl-31998707

RESUMEN

Whereas, bacterial inclusion bodies (IBs) for long were regarded as undesirable aggregates emerging during recombinant protein production, they currently receive attention as promising nanoparticulate biomaterials with diverse applications in biotechnology and biomedicine. We previously identified ssTorA, a signal sequence that normally directs protein export via the Tat pathway in E. coli, as a tag that induces the accumulation of fused proteins into IBs under overexpression conditions. Here, we used targeted mutagenesis to identify features and motifs being either critical or dispensable for IB formation. We found that IB formation is neither related to the function of ssTorA as a Tat-signal sequence nor is it a general feature of this family of signal sequences. IB formation was inhibited by co-overexpression of ssTorA binding chaperones TorD and DnaK and by amino acid substitutions that affect the propensity of ssTorA to form an α-helix. Systematic deletion experiments identified a minimal region of ssTorA required for IB formation in the center of the signal sequence. Unbiased genetic screening of a library of randomly mutagenized ssTorA sequences for reduced aggregation properties allowed us to pinpoint residues that are critical to sustain insoluble expression. Together, the data point to possible mechanisms for the aggregation of ssTorA fusions. Additionally, they led to the design of a tag with superior IB-formation properties compared to the original ssTorA sequence.

15.
Artículo en Inglés | MEDLINE | ID: mdl-29661879

RESUMEN

Due to the rise of drug-resistant forms of tuberculosis, there is an urgent need for novel antibiotics to effectively combat these cases and shorten treatment regimens. Recently, drug screens using whole-cell analyses have been shown to be successful. However, current high-throughput screens focus mostly on stricto sensu life/death screening that give little qualitative information. In doing so, promising compound scaffolds or nonoptimized compounds that fail to reach inhibitory concentrations are missed. To accelerate early tuberculosis (TB) drug discovery, we performed RNA sequencing on Mycobacterium tuberculosis and Mycobacterium marinum to map the stress responses that follow upon exposure to subinhibitory concentrations of antibiotics with known targets, ciprofloxacin, ethambutol, isoniazid, streptomycin, and rifampin. The resulting data set comprises the first overview of transcriptional stress responses of mycobacteria to different antibiotics. We show that antibiotics can be distinguished based on their specific transcriptional stress fingerprint. Notably, this fingerprint was more distinctive in M. marinum We decided to use this to our advantage and continue with this model organism. A selection of diverse antibiotic stress genes was used to construct stress reporters. In total, three functional reporters were constructed to respond to DNA damage, cell wall damage, and ribosomal inhibition. Subsequently, these reporter strains were used to screen a small anti-TB compound library to predict the mode of action. In doing so, we identified the putative modes of action for three novel compounds, which confirms the utility of our approach.


Asunto(s)
Antituberculosos/farmacología , Descubrimiento de Drogas/métodos , Mycobacterium marinum/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Pulmonar/tratamiento farmacológico , Animales , Secuencia de Bases , Línea Celular , Ciprofloxacina/farmacología , Etambutol/farmacología , Humanos , Isoniazida/farmacología , Macrófagos/efectos de los fármacos , Ratones , Mycobacterium marinum/genética , Mycobacterium tuberculosis/genética , Células RAW 264.7 , ARN Bacteriano/genética , Rifampin/farmacología , Análisis de Secuencia de ARN , Estreptomicina/farmacología , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética , Tuberculosis Pulmonar/microbiología
17.
Nat Genet ; 50(2): 307-316, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29358649

RESUMEN

To characterize the genetic determinants of resistance to antituberculosis drugs, we performed a genome-wide association study (GWAS) of 6,465 Mycobacterium tuberculosis clinical isolates from more than 30 countries. A GWAS approach within a mixed-regression framework was followed by a phylogenetics-based test for independent mutations. In addition to mutations in established and recently described resistance-associated genes, novel mutations were discovered for resistance to cycloserine, ethionamide and para-aminosalicylic acid. The capacity to detect mutations associated with resistance to ethionamide, pyrazinamide, capreomycin, cycloserine and para-aminosalicylic acid was enhanced by inclusion of insertions and deletions. Odds ratios for mutations within candidate genes were found to reflect levels of resistance. New epistatic relationships between candidate drug-resistance-associated genes were identified. Findings also suggest the involvement of efflux pumps (drrA and Rv2688c) in the emergence of resistance. This study will inform the design of new diagnostic tests and expedite the investigation of resistance and compensatory epistatic mechanisms.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Tuberculosis Extensivamente Resistente a Drogas/microbiología , Genoma Bacteriano , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Antituberculosos/uso terapéutico , ADN Bacteriano/análisis , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Variación Genética , Estudio de Asociación del Genoma Completo , Geografía , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
18.
Adv Exp Med Biol ; 1019: 155-169, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29116634

RESUMEN

BCG vaccines were derived by in vitro passage, during the years 1908-1921, at the Pasteur Institute of Lille. Following the distribution of stocks of BCG to vaccine production laboratories around the world, it was only a few decades before different BCG producers recognized that there were variants of BCG, likely due to different passaging conditions in the different laboratories. This ultimately led to the lyophilization of stable BCG products in the 1950s and 1960s, but not before considerable evolution of the different BCG strains had taken place. The application of contemporary research methodologies has now revealed genomic, transcriptomic and proteomic differences between BCG strains. These molecular differences in part account for phenotypic differences in vitro between BCG strains, such as their variable secretion of antigenic proteins. Yet, the relevance of BCG variability for immunization policy remains elusive. In this chapter we present an overview of what is known about BCG evolution and its resulting strain variability, and provide some speculation as to the potential relevance for a vaccine given to over 100 million newborns each year.


Asunto(s)
Variación Antigénica , Vacuna BCG/inmunología , Vacunación Masiva , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/prevención & control , Animales , Vacuna BCG/administración & dosificación , Vacuna BCG/química , Vacuna BCG/historia , Bovinos , Evolución Molecular , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Recién Nacido , Mycobacterium bovis/química , Mycobacterium bovis/clasificación , Mycobacterium bovis/inmunología , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/inmunología , Fenotipo , Filogenia , Proteómica , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/microbiología
19.
Lancet Respir Med ; 5(4): 269-281, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28109869

RESUMEN

BACKGROUND: The emergence of programmatically incurable tuberculosis threatens to destabilise control efforts. The aim of this study was to collect prospective patient-level data to inform treatment and containment strategies. METHODS: In a prospective cohort study, 273 South African patients with extensively drug-resistant tuberculosis, or resistance beyond extensively drug-resistant tuberculosis, were followed up over a period of 6 years. Transmission dynamics, infectiousness, and drug susceptibility were analysed in a subset of patients from the Western Cape using whole-genome sequencing (WGS; n=149), a cough aerosol sampling system (CASS; n=26), and phenotypic testing for 18 drugs (n=179). FINDINGS: Between Oct 1, 2008, and Oct 31, 2012, we enrolled and followed up 273 patients for a median of 20·3 months (IQR 9·6-27·8). 203 (74%) had programmatically incurable tuberculosis and unfavourable outcomes (treatment failure, relapse, default, or death despite treatment with a regimen based on capreomycin, aminosalicylic acid, or both). 172 (63%) patients were discharged home, of whom 104 (60%) had an unfavourable outcome. 54 (31%) home-discharged patients had failed treatment, with a median time to death after discharge of 9·9 months (IQR 4·2-17·4). 35 (20%) home-discharged cases were smear-positive at discharge. Using CASS, six (23%) of 26 home-discharged cases with data available expectorated infectious culture-positive cough aerosols in the respirable range (<5 µm), and most reported inter-person contact with suboptimal protective mask usage. WGS identified 17 (19%) of the 90 patients (with available sequence data) that were discharged home before the diagnosis of 20 downstream cases of extensively drug-resistant tuberculosis with almost identical sequencing profiles suggestive of community-based transmission (five or fewer single nucleotide polymorphisms different and with identical resistance-encoding mutations for 14 drugs). 11 (55%) of these downstream cases had HIV co-infection and ten (50%) had died by the end of the study. 22 (56%) of 39 isolates in patients discharged home after treatment failure were resistant to eight or more drugs. However, five (16%) of 31 isolates were susceptible to rifabutin and more than 90% were likely to be sensitive to linezolid, bedaquiline, and delamanid. INTERPRETATION: More than half of the patients with programmatically incurable tuberculosis were discharged into the community where they remained for an average of 16 months, were at risk of expectorating infectious cough aerosols, and posed a threat of transmission of extensively drug-resistant tuberculosis. Urgent action, including appropriate containment strategies, is needed to address this situation. Access to delamanid, bedaquiline, linezolid, and rifabutin, when appropriate, must be accelerated along with comprehensive drug susceptibility testing. FUNDING: UK Medical Research Council, South African Medical Research Council, South African National Research Foundation, European & Developing Countries Clinical Trials Partnership, Oppenheimer Foundation, Newton Fund, Biotechnology and Biological Sciences Research Council, King Abdullah University of Science & Technology.


Asunto(s)
Tuberculosis Extensivamente Resistente a Drogas/mortalidad , Tuberculosis Extensivamente Resistente a Drogas/transmisión , Alta del Paciente/estadística & datos numéricos , Adulto , Antituberculosos/uso terapéutico , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Fenotipo , Estudios Prospectivos , Sudáfrica , Esputo , Insuficiencia del Tratamiento
20.
Sci Rep ; 5: 15443, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26487098

RESUMEN

Although Bacillus Calmette-Guérin (BCG) vaccines against tuberculosis have been available for more than 90 years, their effectiveness has been hindered by variable protective efficacy and a lack of lasting memory responses. One factor contributing to this variability may be the diversity of the BCG strains that are used around the world, in part from genomic changes accumulated during vaccine production and their resulting differences in gene expression. We have compared the genomes and transcriptomes of a global collection of fourteen of the most widely used BCG strains at single base-pair resolution. We have also used quantitative proteomics to identify key differences in expression of proteins across five representative BCG strains of the four tandem duplication (DU) groups. We provide a comprehensive map of single nucleotide polymorphisms (SNPs), copy number variation and insertions and deletions (indels) across fourteen BCG strains. Genome-wide SNP characterization allowed the construction of a new and robust phylogenic genealogy of BCG strains. Transcriptional and proteomic profiling revealed a metabolic remodeling in BCG strains that may be reflected by altered immunogenicity and possibly vaccine efficacy. Together, these integrated-omic data represent the most comprehensive catalogue of genetic variation across a global collection of BCG strains.


Asunto(s)
Vacuna BCG/genética , Pared Celular/genética , Proteómica , Tuberculosis/genética , Aclimatación/genética , Vacuna BCG/administración & dosificación , Pared Celular/efectos de los fármacos , Variaciones en el Número de Copia de ADN/genética , Regulación de la Expresión Génica , Genoma Bacteriano , Humanos , Mycobacterium bovis/efectos de los fármacos , Mycobacterium bovis/patogenicidad , Filogenia , Polimorfismo de Nucleótido Simple , Tuberculosis/microbiología , Tuberculosis/prevención & control
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