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1.
Nature ; 615(7950): 134-142, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36470304

RESUMO

Preventing SARS-CoV-2 infection by modulating viral host receptors, such as angiotensin-converting enzyme 2 (ACE2)1, could represent a new chemoprophylactic approach for COVID-19 that complements vaccination2,3. However, the mechanisms that control the expression of ACE2 remain unclear. Here we show that the farnesoid X receptor (FXR) is a direct regulator of ACE2 transcription in several tissues affected by COVID-19, including the gastrointestinal and respiratory systems. We then use the over-the-counter compound z-guggulsterone and the off-patent drug ursodeoxycholic acid (UDCA) to reduce FXR signalling and downregulate ACE2 in human lung, cholangiocyte and intestinal organoids and in the corresponding tissues in mice and hamsters. We show that the UDCA-mediated downregulation of ACE2 reduces susceptibility to SARS-CoV-2 infection in vitro, in vivo and in human lungs and livers perfused ex situ. Furthermore, we reveal that UDCA reduces the expression of ACE2 in the nasal epithelium in humans. Finally, we identify a correlation between UDCA treatment and positive clinical outcomes after SARS-CoV-2 infection using retrospective registry data, and confirm these findings in an independent validation cohort of recipients of liver transplants. In conclusion, we show that FXR has a role in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the way for future clinical trials.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Receptores Virais , Ácido Ursodesoxicólico , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/prevenção & controle , Receptores Virais/genética , Receptores Virais/metabolismo , Estudos Retrospectivos , SARS-CoV-2/metabolismo , Tratamento Farmacológico da COVID-19 , Cricetinae , Transcrição Gênica , Ácido Ursodesoxicólico/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Organoides/efeitos dos fármacos , Organoides/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , Sistema de Registros , Reprodutibilidade dos Testes , Transplante de Fígado
2.
PLoS Pathog ; 20(5): e1011675, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38696531

RESUMO

Persons living with HIV are known to be at increased risk of developing tuberculosis (TB) disease upon infection with Mycobacterium tuberculosis (Mtb). However, it has remained unclear how HIV co-infection affects subsequent Mtb transmission from these patients. Here, we customized a Bayesian phylodynamic framework to estimate the effects of HIV co-infection on the Mtb transmission dynamics from sequence data. We applied our model to four Mtb genomic datasets collected in sub-Saharan African countries with a generalized HIV epidemic. Our results confirm that HIV co-infection is a strong risk factor for developing active TB. Additionally, we demonstrate that HIV co-infection is associated with a reduced effective reproductive number for TB. Stratifying the population by CD4+ T-cell count yielded similar results, suggesting that, in this context, CD4+ T-cell count is not a better predictor of Mtb transmissibility than HIV infection status alone. Together, our genome-based analyses complement observational household contact studies, and more firmly establish the negative association between HIV co-infection and Mtb transmissibility.


Assuntos
Coinfecção , Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Humanos , África Subsaariana/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/transmissão , Infecções por HIV/epidemiologia , Coinfecção/microbiologia , Coinfecção/epidemiologia , Tuberculose/epidemiologia , Tuberculose/transmissão , Tuberculose/microbiologia , Masculino , Contagem de Linfócito CD4 , Feminino , Teorema de Bayes , Adulto , Fatores de Risco
3.
PLoS Pathog ; 19(4): e1010893, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014917

RESUMO

In settings with high tuberculosis (TB) endemicity, distinct genotypes of the Mycobacterium tuberculosis complex (MTBC) often differ in prevalence. However, the factors leading to these differences remain poorly understood. Here we studied the MTBC population in Dar es Salaam, Tanzania over a six-year period, using 1,082 unique patient-derived MTBC whole-genome sequences (WGS) and associated clinical data. We show that the TB epidemic in Dar es Salaam is dominated by multiple MTBC genotypes introduced to Tanzania from different parts of the world during the last 300 years. The most common MTBC genotypes deriving from these introductions exhibited differences in transmission rates and in the duration of the infectious period, but little differences in overall fitness, as measured by the effective reproductive number. Moreover, measures of disease severity and bacterial load indicated no differences in virulence between these genotypes during active TB. Instead, the combination of an early introduction and a high transmission rate accounted for the high prevalence of L3.1.1, the most dominant MTBC genotype in this setting. Yet, a longer co-existence with the host population did not always result in a higher transmission rate, suggesting that distinct life-history traits have evolved in the different MTBC genotypes. Taken together, our results point to bacterial factors as important determinants of the TB epidemic in Dar es Salaam.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Tanzânia/epidemiologia , Tuberculose/epidemiologia , Genótipo , Virulência
4.
Brain ; 147(7): 2471-2482, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38386308

RESUMO

Neurodevelopmental disorders are major indications for genetic referral and have been linked to more than 1500 loci including genes encoding transcriptional regulators. The dysfunction of transcription factors often results in characteristic syndromic presentations; however, at least half of these patients lack a genetic diagnosis. The implementation of machine learning approaches has the potential to aid in the identification of new disease genes and delineate associated phenotypes. Next generation sequencing was performed in seven affected individuals with neurodevelopmental delay and dysmorphic features. Clinical characterization included reanalysis of available neuroimaging datasets and 2D portrait image analysis with GestaltMatcher. The functional consequences of ZSCAN10 loss were modelled in mouse embryonic stem cells (mESCs), including a knockout and a representative ZSCAN10 protein truncating variant. These models were characterized by gene expression and western blot analyses, chromatin immunoprecipitation and quantitative PCR (ChIP-qPCR) and immunofluorescence staining. Zscan10 knockout mouse embryos were generated and phenotyped. We prioritized bi-allelic ZSCAN10 loss-of-function variants in seven affected individuals from five unrelated families as the underlying molecular cause. RNA-sequencing analyses in Zscan10-/- mESCs indicated dysregulation of genes related to stem cell pluripotency. In addition, we established in mESCs the loss-of-function mechanism for a representative human ZSCAN10 protein truncating variant by showing alteration of its expression levels and subcellular localization, interfering with its binding to DNA enhancer targets. Deep phenotyping revealed global developmental delay, facial asymmetry and malformations of the outer ear as consistent clinical features. Cerebral MRI showed dysplasia of the semicircular canals as an anatomical correlate of sensorineural hearing loss. Facial asymmetry was confirmed as a clinical feature by GestaltMatcher and was recapitulated in the Zscan10 mouse model along with inner and outer ear malformations. Our findings provide evidence of a novel syndromic neurodevelopmental disorder caused by bi-allelic loss-of-function variants in ZSCAN10.


Assuntos
Camundongos Knockout , Transtornos do Neurodesenvolvimento , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Camundongos , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia , Fatores de Transcrição/genética
5.
BMC Infect Dis ; 24(1): 657, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956461

RESUMO

BACKGROUND: Multi-drug or rifamycin-resistant tuberculosis (MDR/RR-TB) is an important public health concern, including in settings with high HIV prevalence. TB drug resistance can be directly transmitted or arise through resistance acquisition during first-line TB treatment. Limited evidence suggests that people living with HIV (PLHIV) might have an increased risk of acquired rifamycin-resistance (ARR). METHODS: To assess HIV as a risk factor for ARR during first-line TB treatment, a systematic review and meta-analysis was conducted. ARR was defined as rifamycin-susceptibility at treatment start with rifamycin-resistance diagnosed during or at the end of treatment, or at recurrence. PubMed/MEDLINE, CINAHL, Cochrane Library, and Google Scholar databases were searched from inception to 23 May 2024 for articles in English; conference abstracts were also searched from 2004 to 2021. The Mantel-Haenszel random-effects model was used to estimate the pooled odds ratio of any association between HIV and ARR among individuals receiving first-line TB treatment. RESULTS: Ten studies that included data collected between 1990 and 2014 were identified: five from the United States, two from South Africa and one each from Uganda, India and Moldova. A total of 97,564 individuals were included across all studies, with 13,359 (13.7%) PLHIV. Overall, 312 (0.32%) acquired rifamycin-resistance, among whom 115 (36.9%) were PLHIV. The weighted odds of ARR were 4.57 (95% CI, 2.01-10.42) times higher among PLHIV compared to HIV-negative individuals receiving first-line TB treatment. CONCLUSION: The available data, suggest that PLHIV have an increased ARR risk during first-line TB treatment. Further research is needed to clarify specific risk factors, including advanced HIV disease and TB disease severity. Given the introduction of shorter, 4-month rifamycin-based regimens, there is an urgent need for additional data on ARR, particularly for PLHIV. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022327337.


Assuntos
Antituberculosos , Infecções por HIV , Rifamicinas , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/complicações , Rifamicinas/uso terapêutico , Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Fatores de Risco , Mycobacterium tuberculosis/efeitos dos fármacos , África do Sul/epidemiologia
6.
BMC Infect Dis ; 24(1): 831, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148008

RESUMO

INTRODUCTION: Tuberculosis (TB) is an important cause of morbidity and mortality among people living with HIV (PLHIV). Current WHO-recommended strategies for diagnosing TB among hospitalized PLHIV rely on symptom screening and disease severity to assess eligibility for urine lipoarabinomannan lateral flow (LF-LAM) and molecular testing. Despite these recommendations, autopsy studies show a large burden of undiagnosed TB among admitted PLHIV. The EXULTANT trial aims to assess the impact of an expanded screening strategy using three specimens (sputum, stool, and urine) for TB diagnosis among PLHIV admitted to hospitals in two high HIV and TB burden African countries. METHODS: This is a multicenter, pragmatic, individually randomized controlled trial conducted across eleven hospitals in Tanzania and Mozambique. Participants in the intervention arm will be tested with Xpert MTB/RIF Ultra® from expectorated sputum, stool, and urine samples, with additional urine LF-LAM testing in the first 24 h after hospital admission, irrespective of the presence of the symptoms. The control arm will implement the WHO standard of care recommendations. Hospitalized adults (≥ 18 years) with a confirmed HIV-diagnosis, irrespective of antiretroviral (ART) therapy status or presence of TB symptoms will be assessed for eligibility at admission. Patients with a pre-existing TB diagnosis, those receiving anti-tuberculosis therapy or tuberculosis preventive treatment in the 6 months prior to enrolment, and those transferred from other hospitals will not be eligible. Also, participants admitted for traumatic reasons such as acute abdomen, maternal conditions, scheduled surgery, having a positive SARS-CoV2 test will be ineligible. The primary endpoint is the proportion of participants with microbiologically confirmed TB starting treatment within 3 days of enrolment. DISCUSSION: The EXULTANT trial investigates rapid implementation after admission of a new diagnostic algorithm using Xpert MTB/RIF Ultra® in several non-invasive specimens, in addition to LF-LAM, in hospitalized PLHIV regardless of TB symptoms. This enhanced strategy is anticipated to detect frequently missed TB cases in this population and is being evaluated as an implementable and scalable intervention. TRIAL REGISTRATION: Trial reference number: NCT04568967 (ClinicalTrials.gov) registered on 2020-09-29.


Assuntos
Infecções por HIV , Tuberculose , Humanos , Moçambique , Tanzânia , Infecções por HIV/complicações , Adulto , Tuberculose/diagnóstico , Tuberculose/complicações , Tuberculose/tratamento farmacológico , Masculino , Feminino , Escarro/microbiologia , Lipopolissacarídeos/urina , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/efeitos dos fármacos , Fezes/microbiologia , Fezes/virologia , Hospitalização
7.
Am J Hum Genet ; 106(3): 338-355, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32109419

RESUMO

The Rho-guanine nucleotide exchange factor (RhoGEF) TRIO acts as a key regulator of neuronal migration, axonal outgrowth, axon guidance, and synaptogenesis by activating the GTPase RAC1 and modulating actin cytoskeleton remodeling. Pathogenic variants in TRIO are associated with neurodevelopmental diseases, including intellectual disability (ID) and autism spectrum disorders (ASD). Here, we report the largest international cohort of 24 individuals with confirmed pathogenic missense or nonsense variants in TRIO. The nonsense mutations are spread along the TRIO sequence, and affected individuals show variable neurodevelopmental phenotypes. In contrast, missense variants cluster into two mutational hotspots in the TRIO sequence, one in the seventh spectrin repeat and one in the RAC1-activating GEFD1. Although all individuals in this cohort present with developmental delay and a neuro-behavioral phenotype, individuals with a pathogenic variant in the seventh spectrin repeat have a more severe ID associated with macrocephaly than do most individuals with GEFD1 variants, who display milder ID and microcephaly. Functional studies show that the spectrin and GEFD1 variants cause a TRIO-mediated hyper- or hypo-activation of RAC1, respectively, and we observe a striking correlation between RAC1 activation levels and the head size of the affected individuals. In addition, truncations in TRIO GEFD1 in the vertebrate model X. tropicalis induce defects that are concordant with the human phenotype. This work demonstrates distinct clinical and molecular disorders clustering in the GEFD1 and seventh spectrin repeat domains and highlights the importance of tight control of TRIO-RAC1 signaling in neuronal development.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Transtornos do Neurodesenvolvimento/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Sequência de Aminoácidos , Estudos de Coortes , Feminino , Fatores de Troca do Nucleotídeo Guanina/química , Células HEK293 , Humanos , Masculino , Fenótipo , Proteínas Serina-Treonina Quinases/química , Homologia de Sequência de Aminoácidos
8.
Clin Infect Dis ; 75(12): 2145-2152, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35579497

RESUMO

BACKGROUND: Microbiologic diagnosis of childhood tuberculosis may be difficult. Oral swab specimens are a potential noninvasive alternative to sputum specimens for diagnosis. METHODS: This was a prospective diagnostic accuracy study of oral swab specimens (buccal and tongue) for pulmonary tuberculosis diagnosis in children (aged ≤ 15 years) in 2 South African hospital sites. Children with cough of any duration as well as a positive tuberculin skin test result, tuberculosis contact, loss of weight, or chest radiograph suggestive of pulmonary tuberculosis were enrolled. Two induced sputum specimens were tested with Xpert MTB/RIF (or Xpert MTB/RIF Ultra) assay and liquid culture. Oral swab specimens were obtained before sputum specimens, frozen, and later tested with Xpert MTB/RIF Ultra. Children were classified as microbiologically confirmed tuberculosis, unconfirmed tuberculosis (receipt of tuberculosis treatment), or unlikely tuberculosis according to National Institutes of Health consensus definitions based on sputum microbiologic results. RESULTS: Among 291 participants (median age [interquartile range], 32 [14-73] months), 57 (20%) had human immunodeficiency virus (HIV), and 87 (30%) were malnourished; 90 (31%) had confirmed pulmonary tuberculosis (rifampicin resistant in 6 [7%] ), 157 (54%), unconfirmed pulmonary tuberculosis, and 44 (15%), unlikely tuberculosis. A single oral swab specimen was obtained from 126 (43%) of the participants (tongue in 96 and buccal in 30) and 2 swab specimens from 165 (57%) (tongue in 110 and buccal in 55). Sensitivity was low (22% [95% confidence interval, 15%-32%]) for all swab specimens combined (with confirmed pulmonary tuberculosis as reference), but specificity was high (100% [91%-100%]). The highest sensitivity was 33% (95% confidence interval, 15%-58%) among participants with HIV. The overall yield was 6.9% with 1 oral swab specimen and 7.2% with 2. CONCLUSIONS: Use of the Xpert MTB/RIF Ultra assay with oral swab specimens provides poor yield for microbiologic pulmonary tuberculosis confirmation in children.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Criança , Humanos , Pré-Escolar , Rifampina/farmacologia , Estudos Prospectivos , Sensibilidade e Especificidade , Tuberculose Pulmonar/diagnóstico , Escarro/microbiologia
9.
Am J Hum Genet ; 104(6): 1210-1222, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31079897

RESUMO

We delineate a KMT2E-related neurodevelopmental disorder on the basis of 38 individuals in 36 families. This study includes 31 distinct heterozygous variants in KMT2E (28 ascertained from Matchmaker Exchange and three previously reported), and four individuals with chromosome 7q22.2-22.23 microdeletions encompassing KMT2E (one previously reported). Almost all variants occurred de novo, and most were truncating. Most affected individuals with protein-truncating variants presented with mild intellectual disability. One-quarter of individuals met criteria for autism. Additional common features include macrocephaly, hypotonia, functional gastrointestinal abnormalities, and a subtle facial gestalt. Epilepsy was present in about one-fifth of individuals with truncating variants and was responsive to treatment with anti-epileptic medications in almost all. More than 70% of the individuals were male, and expressivity was variable by sex; epilepsy was more common in females and autism more common in males. The four individuals with microdeletions encompassing KMT2E generally presented similarly to those with truncating variants, but the degree of developmental delay was greater. The group of four individuals with missense variants in KMT2E presented with the most severe developmental delays. Epilepsy was present in all individuals with missense variants, often manifesting as treatment-resistant infantile epileptic encephalopathy. Microcephaly was also common in this group. Haploinsufficiency versus gain-of-function or dominant-negative effects specific to these missense variants in KMT2E might explain this divergence in phenotype, but requires independent validation. Disruptive variants in KMT2E are an under-recognized cause of neurodevelopmental abnormalities.


Assuntos
Proteínas de Ligação a DNA/genética , Epilepsia/etiologia , Variação Genética , Heterozigoto , Transtornos do Neurodesenvolvimento/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Epilepsia/patologia , Feminino , Haploinsuficiência , Humanos , Lactente , Masculino , Transtornos do Neurodesenvolvimento/patologia , Linhagem , Fenótipo , Adulto Jovem
10.
J Clin Microbiol ; 60(3): e0236221, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35170980

RESUMO

Treatment of multidrug-resistant or rifampicin-resistant tuberculosis (MDR/RR-TB), although improved in recent years with shorter, more tolerable regimens, remains largely standardized and based on limited drug susceptibility testing (DST). More individualized treatment with expanded DST access is likely to improve patient outcomes. To assess the potential of TB drug resistance prediction based on whole-genome sequencing (WGS) to provide more effective treatment regimens, we applied current South African treatment recommendations to a retrospective cohort of MDR/RR-TB patients from Khayelitsha, Cape Town. Routine DST and clinical data were used to retrospectively categorize patients into a recommended regimen, either a standardized short regimen or a longer individualized regimen. Potential regimen changes were then described with the addition of WGS-derived DST. WGS data were available for 1274 MDR/RR-TB patient treatment episodes across 2008 to 2017. Among 834 patients initially eligible for the shorter regimen, 385 (46%) may have benefited from reduced drug dosage or removing ineffective drugs when WGS data were considered. A further 187 (22%) patients may have benefited from more effective adjusted regimens. Among 440 patients initially eligible for a longer individualized regimen, 153 (35%) could have been switched to the short regimen. Overall, 305 (24%) patients had MDR/RR-TB with second-line TB drug resistance, where the availability of WGS-derived DST would have allowed more effective treatment individualization. These data suggest considerable benefits could accrue from routine access to WGS-derived resistance prediction. Advances in culture-free sequencing and expansion of the reference resistance mutation catalogue will increase the utility of WGS resistance prediction.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Estudos de Coortes , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Estudos Retrospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , África do Sul , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
11.
Brain ; 144(12): 3597-3610, 2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34415310

RESUMO

Phosphatidylinositol 4-kinase IIIα (PI4KIIIα/PI4KA/OMIM:600286) is a lipid kinase generating phosphatidylinositol 4-phosphate (PI4P), a membrane phospholipid with critical roles in the physiology of multiple cell types. PI4KIIIα's role in PI4P generation requires its assembly into a heterotetrameric complex with EFR3, TTC7 and FAM126. Sequence alterations in two of these molecular partners, TTC7 (encoded by TTC7A or TCC7B) and FAM126, have been associated with a heterogeneous group of either neurological (FAM126A) or intestinal and immunological (TTC7A) conditions. Here we show that biallelic PI4KA sequence alterations in humans are associated with neurological disease, in particular hypomyelinating leukodystrophy. In addition, affected individuals may present with inflammatory bowel disease, multiple intestinal atresia and combined immunodeficiency. Our cellular, biochemical and structural modelling studies indicate that PI4KA-associated phenotypical outcomes probably stem from impairment of PI4KIIIα-TTC7-FAM126's organ-specific functions, due to defective catalytic activity or altered intra-complex functional interactions. Together, these data define PI4KA gene alteration as a cause of a variable phenotypical spectrum and provide fundamental new insight into the combinatorial biology of the PI4KIIIα-FAM126-TTC7-EFR3 molecular complex.


Assuntos
Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Atresia Intestinal/genética , Antígenos de Histocompatibilidade Menor/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Doenças da Imunodeficiência Primária/genética , Feminino , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único
12.
Antimicrob Agents Chemother ; 65(11): e0036421, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34460307

RESUMO

Rifampin monoresistance (RMR; rifampin resistance and isoniazid susceptibility) accounts for 38% of all rifampin-resistant tuberculosis (RR-TB) in South Africa and is increasing. We aimed to compare RMR-TB with multidrug-resistant TB (MDR-TB) in a setting with high TB, RR-TB, and HIV burdens. Patient-level clinical data and stored RR Mycobacterium tuberculosis isolates from 2008 to 2017 with available whole-genome sequencing (WGS) data were used to describe risk factors associated with RMR-TB and to compare RR-conferring mutations between RMR-TB and MDR-TB. A subset of isolates with particular RR-conferring mutations were subjected to semiquantitative rifampin phenotypic drug susceptibility testing. Among 2,041 routinely diagnosed RR-TB patients, 463 (22.7%) had RMR-TB. HIV-positive individuals (adjusted odds ratio [aOR], 1.4; 95% confidence interval [CI], 1.1 to 1.9) and diagnosis between 2013 and 2017 versus between 2008 and 2012 (aOR, 1.3; 95% CI, 1.1 to 1.7) were associated with RMR-TB. Among 1,119 (54.8%) patients with available WGS data showing RR-TB, significant differences in the distribution of rpoB RR-conferring mutations between RMR and MDR isolates were observed. Mutations associated with high-level RR were more commonly found among MDR isolates (811/889 [90.2%] versus 162/230 [70.4%] among RMR isolates; P < 0.0001). In particular, the rpoB L430P mutation, conferring low-level RR, was identified in 32/230 (13.9%) RMR isolates versus 10/889 (1.1%) in MDR isolates (P < 0.0001). Among 10 isolates with an rpoB L430P mutation, 7 were phenotypically susceptible using the critical concentration of 0.5 µg/ml (range, 0.125 to 1 µg/ml). The majority (215/230 [93.5%]) of RMR isolates showed susceptibility to all other TB drugs, highlighting the potential benefits of WGS for simplified treatment. These data suggest that the evolution of RMR-TB differs from MDR-TB with a potential contribution from HIV infection.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Antituberculosos/farmacologia , Infecções por HIV/tratamento farmacológico , Humanos , Isoniazida , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Rifampina , África do Sul , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
13.
Genet Med ; 23(2): 408-414, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33033404

RESUMO

PURPOSE: Lamins are the major component of nuclear lamina, maintaining structural integrity of the nucleus. Lamin A/C variants are well established to cause a spectrum of disorders ranging from myopathies to progeria, termed laminopathies. Phenotypes resulting from variants in LMNB1 and LMNB2 have been much less clearly defined. METHODS: We investigated exome and genome sequencing from the Deciphering Developmental Disorders Study and the 100,000 Genomes Project to identify novel microcephaly genes. RESULTS: Starting from a cohort of patients with extreme microcephaly, 13 individuals with heterozygous variants in the two human B-type lamins were identified. Recurrent variants were established to be de novo in nine cases and shown to affect highly conserved residues within the lamin ɑ-helical rod domain, likely disrupting interactions required for higher-order assembly of lamin filaments. CONCLUSION: We identify dominant pathogenic variants in LMNB1 and LMNB2 as a genetic cause of primary microcephaly, implicating a major structural component of the nuclear envelope in its etiology and defining a new form of laminopathy. The distinct nature of this lamin B-associated phenotype highlights the strikingly different developmental requirements for lamin paralogs and suggests a novel mechanism for primary microcephaly warranting future investigation.


Assuntos
Laminopatias , Microcefalia , Humanos , Lamina Tipo B/genética , Microcefalia/genética
14.
Brain ; 143(8): 2380-2387, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32658972

RESUMO

The SLC12 gene family consists of SLC12A1-SLC12A9, encoding electroneutral cation-coupled chloride co-transporters. SCL12A2 has been shown to play a role in corticogenesis and therefore represents a strong candidate neurodevelopmental disorder gene. Through trio exome sequencing we identified de novo mutations in SLC12A2 in six children with neurodevelopmental disorders. All had developmental delay or intellectual disability ranging from mild to severe. Two had sensorineural deafness. We also identified SLC12A2 variants in three individuals with non-syndromic bilateral sensorineural hearing loss and vestibular areflexia. The SLC12A2 de novo mutation rate was demonstrated to be significantly elevated in the deciphering developmental disorders cohort. All tested variants were shown to reduce co-transporter function in Xenopus laevis oocytes. Analysis of SLC12A2 expression in foetal brain at 16-18 weeks post-conception revealed high expression in radial glial cells, compatible with a role in neurogenesis. Gene co-expression analysis in cells robustly expressing SLC12A2 at 16-18 weeks post-conception identified a transcriptomic programme associated with active neurogenesis. We identify SLC12A2 de novo mutations as the cause of a novel neurodevelopmental disorder and bilateral non-syndromic sensorineural hearing loss and provide further data supporting a role for this gene in human neurodevelopment.


Assuntos
Vestibulopatia Bilateral/genética , Perda Auditiva Neurossensorial/genética , Transtornos do Neurodesenvolvimento/genética , Membro 2 da Família 12 de Carreador de Soluto/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mutação , Adulto Jovem
15.
Nature ; 520(7545): 94-8, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25600267

RESUMO

The regulated release of anorexigenic α-melanocyte stimulating hormone (α-MSH) and orexigenic Agouti-related protein (AgRP) from discrete hypothalamic arcuate neurons onto common target sites in the central nervous system has a fundamental role in the regulation of energy homeostasis. Both peptides bind with high affinity to the melanocortin-4 receptor (MC4R); existing data show that α-MSH is an agonist that couples the receptor to the Gαs signalling pathway, while AgRP binds competitively to block α-MSH binding and blocks the constitutive activity mediated by the ligand-mimetic amino-terminal domain of the receptor. Here we show that, in mice, regulation of firing activity of neurons from the paraventricular nucleus of the hypothalamus (PVN) by α-MSH and AgRP can be mediated independently of Gαs signalling by ligand-induced coupling of MC4R to closure of inwardly rectifying potassium channel, Kir7.1. Furthermore, AgRP is a biased agonist that hyperpolarizes neurons by binding to MC4R and opening Kir7.1, independently of its inhibition of α-MSH binding. Consequently, Kir7.1 signalling appears to be central to melanocortin-mediated regulation of energy homeostasis within the PVN. Coupling of MC4R to Kir7.1 may explain unusual aspects of the control of energy homeostasis by melanocortin signalling, including the gene dosage effect of MC4R and the sustained effects of AgRP on food intake.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/citologia , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Receptor Tipo 4 de Melanocortina/metabolismo , Potenciais de Ação , Proteína Relacionada com Agouti/metabolismo , Animais , Ingestão de Alimentos/genética , Metabolismo Energético , Feminino , Células HEK293 , Homeostase/genética , Humanos , Ligantes , Masculino , Melanocortinas/metabolismo , Camundongos , Receptor Tipo 4 de Melanocortina/genética , Transdução de Sinais/genética , alfa-MSH/metabolismo
16.
Hum Mutat ; 41(5): 1042-1050, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32097528

RESUMO

Pathogenic variants in ZMYND11, which acts as a transcriptional repressor, have been associated with intellectual disability, behavioral abnormalities, and seizures. Only 11 affected individuals have been reported to date, and the phenotype associated with pathogenic variants in this gene have not been fully defined. Here, we present 16 additional patients with predicted pathogenic heterozygous variants in including four individuals from the same family, to further delineate and expand the genotypic and phenotypic spectrum of ZMYND11-related syndromic intellectual disability. The associated phenotype includes developmental delay, particularly affecting speech, mild-moderate intellectual disability, significant behavioral abnormalities, seizures, and hypotonia. There are subtle shared dysmorphic features, including prominent eyelashes and eyebrows, a depressed nasal bridge with bulbous nasal tip, anteverted nares, thin vermilion of the upper lip, and wide mouth. Novel features include brachydactyly and tooth enamel hypoplasia. Most identified variants are likely to result in premature truncation and/or nonsense-mediated decay. Two ZMYND11 variants located in the final exon-p.(Gln586*) (likely escaping nonsense-mediated decay) and p.(Cys574Arg)-are predicted to disrupt the MYND-type zinc-finger motif and likely interfere with binding to its interaction partners. Hence, the homogeneous phenotype likely results from a common mechanism of loss-of-function.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Correpressoras/genética , Proteínas de Ligação a DNA/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Alelos , Criança , Pré-Escolar , Fácies , Feminino , Estudos de Associação Genética/métodos , Genótipo , Haploinsuficiência , Humanos , Masculino , Mutação , Degradação do RNAm Mediada por Códon sem Sentido , Fenótipo , Síndrome , Dedos de Zinco
17.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32718966

RESUMO

We analyzed 312 drug-resistant genomes of Mycobacterium tuberculosis isolates collected from HIV-coinfected and HIV-negative TB patients from nine countries with a high tuberculosis burden. We found that rifampicin-resistant M. tuberculosis strains isolated from HIV-coinfected patients carried disproportionally more resistance-conferring mutations in rpoB that are associated with a low fitness in the absence of the drug, suggesting these low-fitness rpoB variants can thrive in the context of reduced host immunity.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Rifampina
18.
Am J Hum Genet ; 100(1): 138-150, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28017370

RESUMO

Early B cell factor 3 (EBF3) is an atypical transcription factor that is thought to influence the laminar formation of the cerebral cortex. Here, we report that de novo mutations in EBF3 cause a complex neurodevelopmental syndrome. The mutations were identified in two large-scale sequencing projects: the UK Deciphering Developmental Disorders (DDD) study and the Canadian Clinical Assessment of the Utility of Sequencing and Evaluation as a Service (CAUSES) study. The core phenotype includes moderate to severe intellectual disability, and many individuals exhibit cerebellar ataxia, subtle facial dysmorphism, strabismus, and vesicoureteric reflux, suggesting that EBF3 has a widespread developmental role. Pathogenic de novo variants identified in EBF3 include multiple loss-of-function and missense mutations. Structural modeling suggested that the missense mutations affect DNA binding. Functional analysis of mutant proteins with missense substitutions revealed reduced transcriptional activities and abilities to form heterodimers with wild-type EBF3. We conclude that EBF3, a transcription factor previously unknown to be associated with human disease, is important for brain and other organ development and warrants further investigation.


Assuntos
Mutação , Transtornos do Neurodesenvolvimento/genética , Fatores de Transcrição/genética , Adolescente , Idade de Início , Ataxia/genética , Canadá , Criança , DNA/metabolismo , Deficiências do Desenvolvimento/genética , Face/anormalidades , Feminino , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/genética , Masculino , Mutação de Sentido Incorreto/genética , Estrabismo/genética , Síndrome , Fatores de Transcrição/metabolismo , Reino Unido
19.
Lancet ; 393(10181): 1642-1656, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30904262

RESUMO

Tuberculosis remains the leading cause of death from an infectious disease among adults worldwide, with more than 10 million people becoming newly sick from tuberculosis each year. Advances in diagnosis, including the use of rapid molecular testing and whole-genome sequencing in both sputum and non-sputum samples, could change this situation. Although little has changed in the treatment of drug-susceptible tuberculosis, data on increased efficacy with new and repurposed drugs have led WHO to recommend all-oral therapy for drug-resistant tuberculosis for the first time ever in 2018. Studies have shown that shorter latent tuberculosis prevention regimens containing rifampicin or rifapentine are as effective as longer, isoniazid-based regimens, and there is a promising vaccine candidate to prevent the progression of infection to the disease. But new tools alone are not sufficient. Advances must be made in providing high-quality, people-centred care for tuberculosis. Renewed political will, coupled with improved access to quality care, could relegate the morbidity, mortality, and stigma long associated with tuberculosis, to the past.


Assuntos
Carga Global da Doença , Tuberculose , Antituberculosos/uso terapêutico , Resistência a Medicamentos/efeitos dos fármacos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
20.
Genet Med ; 22(7): 1215-1226, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32376980

RESUMO

PURPOSE: Somatic variants in tumor necrosis factor receptor-associated factor 7 (TRAF7) cause meningioma, while germline variants have recently been identified in seven patients with developmental delay and cardiac, facial, and digital anomalies. We aimed to define the clinical and mutational spectrum associated with TRAF7 germline variants in a large series of patients, and to determine the molecular effects of the variants through transcriptomic analysis of patient fibroblasts. METHODS: We performed exome, targeted capture, and Sanger sequencing of patients with undiagnosed developmental disorders, in multiple independent diagnostic or research centers. Phenotypic and mutational comparisons were facilitated through data exchange platforms. Whole-transcriptome sequencing was performed on RNA from patient- and control-derived fibroblasts. RESULTS: We identified heterozygous missense variants in TRAF7 as the cause of a developmental delay-malformation syndrome in 45 patients. Major features include a recognizable facial gestalt (characterized in particular by blepharophimosis), short neck, pectus carinatum, digital deviations, and patent ductus arteriosus. Almost all variants occur in the WD40 repeats and most are recurrent. Several differentially expressed genes were identified in patient fibroblasts. CONCLUSION: We provide the first large-scale analysis of the clinical and mutational spectrum associated with the TRAF7 developmental syndrome, and we shed light on its molecular etiology through transcriptome studies.


Assuntos
Deficiência Intelectual , Transcriptoma , Exoma , Células Germinativas , Humanos , Deficiência Intelectual/genética , Mutação de Sentido Incorreto , Fenótipo , Transcriptoma/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral
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