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1.
Lancet Microbe ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38964359

RESUMO

Tuberculosis is a leading cause of death from an infectious agent globally. Infectious subclinical tuberculosis accounts for almost half of all tuberculosis cases in national tuberculosis prevalence surveys, and possibly contributes to transmission and might be associated with morbidity. Modelling studies suggest that new tuberculosis vaccines could have substantial health and economic effects, partly based on the assumptions made regarding subclinical tuberculosis. Evaluating the efficacy of prevention of disease tuberculosis vaccines intended for preventing both clinical and subclinical tuberculosis is a priority. Incorporation of subclinical tuberculosis as a composite endpoint in tuberculosis vaccine trials can help to reduce the sample size and duration of follow-up and to evaluate the efficacy of tuberculosis vaccines in preventing clinical and subclinical tuberculosis. Several design options with various benefits, limitations, and ethical considerations are possible in this regard, which would allow for the generation of the evidence needed to estimate the positive global effects of tuberculosis vaccine trials, in addition to informing policy and vaccination strategies.

2.
JMIR Pediatr Parent ; 7: e51743, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949860

RESUMO

BACKGROUND: Tuberculosis (TB) remains a major cause of morbidity and death worldwide, with a significant impact on children, especially those under the age of 5 years. The complex diagnosis of pediatric TB, compounded by limited access to more accurate diagnostic tests, underscores the need for improved tools to enhance diagnosis and care in resource-limited settings. OBJECTIVE: This study aims to present a telemedicine web platform, BITScreen PTB (Biomedical Image Technologies Screen for Pediatric Tuberculosis), aimed at improving the evaluation of pulmonary TB in children based on digital chest x-ray (CXR) imaging and clinical information in resource-limited settings. METHODS: The platform was evaluated by 3 independent expert readers through a retrospective assessment of a data set with 218 imaging examinations of children under 3 years of age, selected from a previous study performed in Mozambique. The key aspects assessed were the usability through a standardized questionnaire, the time needed to complete the assessment through the platform, the performance of the readers to identify TB cases based on the CXR, the association between the TB features identified in the CXRs and the initial diagnostic classification, and the interreader agreement of the global assessment and the radiological findings. RESULTS: The platform's usability and user satisfaction were evaluated using a questionnaire, which received an average rating of 4.4 (SD 0.59) out of 5. The average examination completion time ranged from 35 to 110 seconds. In addition, the study on CXR showed low sensitivity (16.3%-28.2%) but high specificity (91.1%-98.2%) in the assessment of the consensus case definition of pediatric TB using the platform. The CXR finding having a stronger association with the initial diagnostic classification was air space opacification (χ21>20.38, P<.001). The study found varying levels of interreader agreement, with moderate/substantial agreement for air space opacification (κ=0.54-0.67) and pleural effusion (κ=0.43-0.72). CONCLUSIONS: Our findings support the promising role of telemedicine platforms such as BITScreen PTB in enhancing pediatric TB diagnosis access, particularly in resource-limited settings. Additionally, these platforms could facilitate the multireader and systematic assessment of CXR in pediatric TB clinical studies.

3.
Trends Mol Med ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886138

RESUMO

Herpes simplex virus type 1 (HSV-1) is a DNA virus and human pathogen used to construct promising therapeutic vectors. HSV-1 vectors fall into two classes: replication-selective oncolytic vectors for cancer therapy and defective non-replicative vectors for gene therapy. Vectors from each class can accommodate ≥30 kb of inserts, have been approved clinically, and demonstrate a relatively benign safety profile. Despite oncolytic HSV (oHSV) replication in tumors and elicited immune responses, the virus is well tolerated in cancer patients. Current non-replicative vectors elicit only limited immune responses. Seropositivity and immune responses against HSV-1 do not eliminate either the vector or infected cells, and the vectors can therefore be re-administered. In this review we highlight vectors that have been translated to the clinic and host-virus immune interactions that impact on the safety and efficacy of HSVs.

4.
Am J Hum Genet ; 111(6): 1061-1083, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38723632

RESUMO

To identify credible causal risk variants (CCVs) associated with different histotypes of epithelial ovarian cancer (EOC), we performed genome-wide association analysis for 470,825 genotyped and 10,163,797 imputed SNPs in 25,981 EOC cases and 105,724 controls of European origin. We identified five histotype-specific EOC risk regions (p value <5 × 10-8) and confirmed previously reported associations for 27 risk regions. Conditional analyses identified an additional 11 signals independent of the primary signal at six risk regions (p value <10-5). Fine mapping identified 4,008 CCVs in these regions, of which 1,452 CCVs were located in ovarian cancer-related chromatin marks with significant enrichment in active enhancers, active promoters, and active regions for CCVs from each EOC histotype. Transcriptome-wide association and colocalization analyses across histotypes using tissue-specific and cross-tissue datasets identified 86 candidate susceptibility genes in known EOC risk regions and 32 genes in 23 additional genomic regions that may represent novel EOC risk loci (false discovery rate <0.05). Finally, by integrating genome-wide HiChIP interactome analysis with transcriptome-wide association study (TWAS), variant effect predictor, transcription factor ChIP-seq, and motifbreakR data, we identified candidate gene-CCV interactions at each locus. This included risk loci where TWAS identified one or more candidate susceptibility genes (e.g., HOXD-AS2, HOXD8, and HOXD3 at 2q31) and other loci where no candidate gene was identified (e.g., MYC and PVT1 at 8q24) by TWAS. In summary, this study describes a functional framework and provides a greater understanding of the biological significance of risk alleles and candidate gene targets at EOC susceptibility loci identified by a genome-wide association study.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Ovarianas , Polimorfismo de Nucleotídeo Único , Humanos , Feminino , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário/genética , Transcriptoma , Fatores de Risco , Genômica/métodos , Estudos de Casos e Controles , Multiômica
5.
Glob Chang Biol ; 30(5): e17295, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38804108

RESUMO

Plant-soil biodiversity interactions are fundamental for the functioning of terrestrial ecosystems. Yet, the existence of a set of globally distributed topsoil microbial and small invertebrate organisms consistently associated with land plants (i.e., their consistent soil-borne microbiome), together with the environmental preferences and functional capabilities of these organisms, remains unknown. We conducted a standardized field survey under 150 species of land plants, including 58 species of bryophytes and 92 of vascular plants, across 124 locations from all continents. We found that, despite the immense biodiversity of soil organisms, the land plants evaluated only shared a small fraction (less than 1%) of all microbial and invertebrate taxa that were present across contrasting climatic and soil conditions and vegetation types. These consistent taxa were dominated by generalist decomposers and phagotrophs and their presence was positively correlated with the abundance of functional genes linked to mineralization. Finally, we showed that crossing environmental thresholds in aridity (aridity index of 0.65, i.e., the transition from mesic to dry ecosystems), soil pH (5.5; i.e., the transition from acidic to strongly acidic soils), and carbon (less than 2%, the lower limit of fertile soils) can result in drastic disruptions in the associations between land plants and soil organisms, with potential implications for the delivery of soil ecosystem processes under ongoing global environmental change.


Assuntos
Embriófitas , Microbiota , Microbiologia do Solo , Biodiversidade , Solo/química
6.
Adv Healthc Mater ; : e2302362, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563704

RESUMO

Cerebral neural electronics play a crucial role in neuroscience research with increasing translational applications such as brain-computer interfaces for sensory input and motor output restoration. While widely utilized for decades, the understanding of the cellular mechanisms underlying this technology remains limited. Although two-photon microscopy (TPM) has shown great promise in imaging superficial neural electrodes, its application to deep-penetrating electrodes is technically difficult. Here, a novel device integrating transparent microelectrode arrays with glass microprisms, enabling electrophysiology recording and stimulation alongside TPM imaging across all cortical layers in a vertical plane, is introduced. Tested in Thy1-GCaMP6 mice for over 4 months, the integrated device demonstrates the capability for multisite electrophysiological recording/stimulation and simultaneous TPM calcium imaging. As a proof of concept, the impact of microstimulation amplitude, frequency, and depth on neural activation patterns is investigated using the setup. With future improvements in material stability and single unit yield, this multimodal tool greatly expands integrated electrophysiology and optical imaging from the superficial brain to the entire cortical column, opening new avenues for neuroscience research and neurotechnology development.

7.
medRxiv ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38645191

RESUMO

Background: Globally, over one-third of pulmonary tuberculosis (TB) disease diagnoses are made based on clinical criteria after a negative diagnostic test result. Understanding factors associated with clinicians' decisions to initiate treatment for individuals with negative test results is critical for predicting the potential impact of new diagnostics. Methods: We performed a systematic review and individual patient data meta-analysis using studies conducted between January/2010 and December/2022 (PROSPERO: CRD42022287613). We included trials or cohort studies that enrolled individuals evaluated for TB in routine settings. In these studies participants were evaluated based on clinical examination and routinely-used diagnostics, and were followed for ≥1 week after the initial test result. We used hierarchical Bayesian logistic regression to identify factors associated with treatment initiation following a negative result on an initial bacteriological test (e.g., sputum smear microscopy, Xpert MTB/RIF). Findings: Multiple factors were positively associated with treatment initiation: male sex [adjusted Odds Ratio (aOR) 1.61 (1.31-1.95)], history of prior TB [aOR 1.36 (1.06-1.73)], reported cough [aOR 4.62 (3.42-6.27)], reported night sweats [aOR 1.50 (1.21-1.90)], and having HIV infection but not on ART [aOR 1.68 (1.23-2.32)]. Treatment initiation was substantially less likely for individuals testing negative with Xpert [aOR 0.77 (0.62-0.96)] compared to smear microscopy and declined in more recent years. Interpretation: Multiple factors influenced decisions to initiate TB treatment despite negative test results. Clinicians were substantially less likely to treat in the absence of a positive test result when using more sensitive, PCR-based diagnostics.

8.
Cell Rep ; 43(4): 113970, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38512868

RESUMO

To meet the high energy demands of brain function, cerebral blood flow (CBF) parallels changes in neuronal activity by a mechanism known as neurovascular coupling (NVC). However, which neurons play a role in mediating NVC is not well understood. Here, we identify in mice and humans a specific population of cortical GABAergic neurons that co-express neuronal nitric oxide synthase and tachykinin receptor 1 (Tacr1). Through whole-tissue clearing, we demonstrate that Tacr1 neurons extend local and long-range projections across functionally connected cortical areas. We show that whisker stimulation elicited Tacr1 neuron activity in the barrel cortex through feedforward excitatory pathways. Additionally, through optogenetic experiments, we demonstrate that Tacr1 neurons are instrumental in mediating CBF through the relaxation of mural cells in a similar fashion to whisker stimulation. Finally, by electron microscopy, we observe that Tacr1 processes contact astrocytic endfeet. These findings suggest that Tacr1 neurons integrate cortical activity to mediate NVC.


Assuntos
Acoplamento Neurovascular , Animais , Camundongos , Acoplamento Neurovascular/fisiologia , Humanos , Neurônios/metabolismo , Neurônios/fisiologia , Vibrissas/fisiologia , Camundongos Endogâmicos C57BL , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Masculino , Córtex Cerebral/fisiologia , Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Óxido Nítrico Sintase Tipo I/metabolismo
10.
Lancet Microbe ; 5(5): e433-e441, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461830

RESUMO

BACKGROUND: Despite increasing availability of rapid molecular tests for the diagnosis of tuberculosis in high-burden settings, many people with tuberculosis are undiagnosed. Reliance on sputum as the primary specimen for tuberculosis diagnostics contributes to this diagnostic gap. We evaluated the diagnostic accuracy and additive yield of a novel stool quantitative PCR (qPCR) assay for the diagnosis of tuberculosis in three countries in Africa with high tuberculosis burdens. METHODS: We undertook a prospective diagnostic accuracy study in Eswatini, Mozambique, and Tanzania from Sept 21, 2020, to Feb 2, 2023, to compare the diagnostic accuracy for tuberculosis of a novel stool qPCR test with the current diagnostic standard for Mycobacterium tuberculosis DNA detection from sputum and stool, Xpert-MTB/RIF Ultra (Xpert Ultra). Sputum, stool, and urine samples were provided by a cohort of participants, aged 10 years or older, diagnosed with tuberculosis. Participants with tuberculosis (cases) were enrolled within 72 h of treatment initiation for tuberculosis diagnosed clinically or following laboratory confirmation. Participants without tuberculosis (controls) consisted of household contacts of the cases who did not develop tuberculosis during a 6-month follow-up. The performance was compared with a robust composite microbiological reference standard (CMRS). FINDINGS: The cohort of adolescents and adults (n=408) included 268 participants with confirmed or clinical tuberculosis (cases), 147 (55%) of whom were living with HIV, and 140 participants (controls) without tuberculosis. The sensitivity of the novel stool qPCR was 93·7% (95% CI 87·4-97·4) compared with participants with detectable growth on M tuberculosis culture, and 88·1% (81·3-93·0) compared with sputum Xpert Ultra. The stool qPCR had an equivalent sensitivity as sputum Xpert Ultra (94·8%, 89·1-98·1) compared with culture. Compared with the CMRS, the sensitivity of the stool qPCR was higher than the current standard for tuberculosis diagnostics on stool, Xpert Ultra (80·4%, 73·4-86·2 vs 73·5%, 66·0-80·1; p=0·025 on paired comparison). The qPCR also identified 17-21% additional tuberculosis cases compared to sputum Xpert Ultra or sputum culture. In controls without tuberculosis, the specificity of the stool qPCR was 96·9% (92·2-99·1). INTERPRETATION: In this study, a novel qPCR for the diagnosis of tuberculosis from stool specimens had a higher accuracy in adolescents and adults than the current diagnostic PCR gold standard on stool, Xpert-MTB/RIF Ultra, and equivalent sensitivity to Xpert-MTB/RIF Ultra on sputum. FUNDING: National Institutes of Health (NIH) Allergy and Infectious Diseases, and NIH Fogarty International Center.


Assuntos
Fezes , Mycobacterium tuberculosis , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Escarro , Tuberculose , Humanos , Adolescente , Fezes/microbiologia , Fezes/química , Adulto , Estudos Prospectivos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Feminino , Masculino , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto Jovem , Tuberculose/diagnóstico , Tuberculose/microbiologia , Tuberculose/urina , Escarro/microbiologia , Pessoa de Meia-Idade , Criança , Tanzânia/epidemiologia , DNA Bacteriano/análise , Moçambique/epidemiologia
11.
J Neural Eng ; 21(2)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38537268

RESUMO

Objective. Intracortical microstimulation (ICMS) can be an effective method for restoring sensory perception in contemporary brain-machine interfaces. However, the mechanisms underlying better control of neuronal responses remain poorly understood, as well as the relationship between neuronal activity and other concomitant phenomena occurring around the stimulation site.Approach. Different microstimulation frequencies were investigatedin vivoon Thy1-GCaMP6s mice using widefield and two-photon imaging to evaluate the evoked excitatory neural responses across multiple spatial scales as well as the induced hemodynamic responses. Specifically, we quantified stimulation-induced neuronal activation and depression in the mouse visual cortex and measured hemodynamic oxyhemoglobin and deoxyhemoglobin signals using mesoscopic-scale widefield imaging.Main results. Our calcium imaging findings revealed a preference for lower-frequency stimulation in driving stronger neuronal activation. A depressive response following the neural activation preferred a slightly higher frequency stimulation compared to the activation. Hemodynamic signals exhibited a comparable spatial spread to neural calcium signals. Oxyhemoglobin concentration around the stimulation site remained elevated during the post-activation (depression) period. Somatic and neuropil calcium responses measured by two-photon microscopy showed similar dependence on stimulation parameters, although the magnitudes measured in soma was greater than in neuropil. Furthermore, higher-frequency stimulation induced a more pronounced activation in soma compared to neuropil, while depression was predominantly induced in soma irrespective of stimulation frequencies.Significance. These results suggest that the mechanism underlying depression differs from activation, requiring ample oxygen supply, and affecting neurons. Our findings provide a novel understanding of evoked excitatory neuronal activity induced by ICMS and offer insights into neuro-devices that utilize both activation and depression phenomena to achieve desired neural responses.


Assuntos
Cálcio , Córtex Visual , Camundongos , Animais , Estimulação Luminosa , Oxiemoglobinas , Neurônios/fisiologia , Estimulação Elétrica/métodos
12.
Sci Rep ; 14(1): 6397, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493233

RESUMO

Modular hip implants allow intra-operative adjustments for patient-specific customization and targeted replacement of damaged elements without full implant extraction. However, challenges arise from relative micromotions between components, potentially leading to implant failure due to cytotoxic metal debris. In this study magnitude and directions of micromotions at the taper junction were estimated, aiming to understand the effect of variations in head size and neck length. Starting from a reference configuration adhering to the 12/14 taper standard, six additional implant configurations were generated by varying the head size and/or neck length. A musculoskeletal multibody model of a prothesized lower limb was developed to estimate hip contact force and location during a normal walking task. Following the implant assembly, the multibody-derived loads were imposed as boundary conditions in a finite element analysis to compute the taper junction micromotions as the relative slip between the contacting surfaces. Results highlighted the L-size head as the most critical configuration, indicating a 2.81 µm relative slip at the mid-stance phase. The proposed approach enables the investigation of geometric variations in implants under accurate load conditions, providing valuable insights for designing less risky prostheses and informing clinical decision-making processes.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Desenho de Prótese , Fenômenos Mecânicos , Metais , Corrosão
13.
iScience ; 27(4): 109371, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38510113

RESUMO

Cerebral microbleeds (CMBs) are associated with higher risk for various neurological diseases including stroke, dementia, and Alzheimer's disease. However, the understanding of cellular pathology of CMBs, particularly in deep brain regions, remains limited. Utilizing two-photon microscopy and microprism implantation, we longitudinally imaged the impact of CMBs on neuronal and microglial activities across cortical depths in awake mice. A temporary decline in spontaneous neuronal activity occurred throughout cortical layers, followed by recovery within a week. However, significant changes of neuron-neuron activity correlations persisted for weeks. Moreover, microglial contact with neuron soma significantly increased post-microbleeds, indicating an important modulatory role of microglia. Notably, microglial contact, negatively correlated with neuronal firing rate in normal conditions, became uncorrelated after microbleeds, suggesting a decreased neuron-microglia inhibition. These findings reveal chronic alterations in cortical neuronal networks and microglial-neuronal interactions across cortical depths, shedding light on the pathology of CMBs.

14.
Lancet Reg Health Am ; 31: 100668, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38500958

RESUMO

Background: The increased risk of tuberculosis (TB) among people deprived of liberty (PDL) is due to individual and institution-level factors. We followed a cohort of PDL from 5 prisons in Paraguay to describe the risk of TB during incarceration and after they were released. Methods: We linked a 2013 national census of prisons with TB records from the TB Program from 2010 to 2021 to identify TB notifications among incarcerated and formerly incarcerated individuals. We used multivariable Cox regression models to quantify the risk of TB during and following incarceration and to identify risk factors associated with TB. Findings: Among 2996 individuals incarcerated, 451 (15.1%) were diagnosed with TB. Of these, 262 (58.1%) cases occurred during incarceration and 189 (41.9%) occurred in the community after release. In prison, the hazard ratio of developing TB was 1.97 (95% CI: 1.52-2.61) after six months of incarceration and increased to 2.78 (95% CI: 1.82-4.24) after 36 months compared with the first six months. The overall TB notification rate was 2940 per 100,000 person-years. This rate increased with the duration of incarceration from 1335 per 100,000 person-years in the first year to 8455 per 100,000 person-years after 8 years. Among former prisoners, the rate of TB decreased from 1717 in the first year after release to 593 per 100 000 person-years after 8 years of follow up. Interpretation: Our study shows the alarming risk of TB associated with prison environments in Paraguay, and how this risk persists for years following incarceration. Effective TB control measures to protect the health of people during and following incarceration are urgently needed. Funding: Paraguay National Commission of Science and Technology grant CONACYT PIN 15-705 (GS, GES, SA).

15.
BMC Med ; 22(1): 103, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38454385

RESUMO

BACKGROUND: The emergence of new SARS-CoV-2 variants and the waning of immunity raise concerns about vaccine effectiveness and protection against COVID-19. While antibody response has been shown to correlate with the risk of infection with the original variant and earlier variants of concern, the effectiveness of antibody-mediated protection against Omicron and the factors associated with protection remain uncertain. METHODS: We evaluated antibody responses to SARS-CoV-2 spike (S) and nucleocapsid (N) antigens from Wuhan and variants of concern by Luminex and their role in preventing breakthrough infections 1 year after a third dose of mRNA vaccination, in a cohort of health care workers followed since the pandemic onset in Spain (N = 393). Data were analyzed in relation to COVID-19 history, demographic factors, comorbidities, vaccine doses, brand, and adverse events. RESULTS: Higher levels of anti-S IgG and IgA to Wuhan, Delta, and Omicron were associated with protection against vaccine breakthroughs (IgG against Omicron S antigen HR, 0.06, 95%CI, 0.26-0.01). Previous SARS-CoV-2 infection was positively associated with antibody levels and protection against breakthroughs, and a longer time since last infection was associated with lower protection. In addition, priming with BNT162b2 followed by mRNA-1273 booster was associated with higher antibody responses than homologous mRNA-1273 vaccination. CONCLUSIONS: Data show that IgG and IgA induced by vaccines against the original strain or by hybrid immunization are valid correlates of protection against Omicron BA.1 despite immune escape and support the benefits of heterologous vaccination regimens to enhance antibodies and the prioritization of booster vaccination in individuals without recent infections.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Vacina de mRNA-1273 contra 2019-nCoV , SARS-CoV-2 , Vacina BNT162 , Infecções Irruptivas , Vacinação , Imunoglobulina A , Imunoglobulina G , Anticorpos Antivirais
16.
BMC Infect Dis ; 24(1): 233, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383310

RESUMO

BACKGROUND: Tuberculosis (TB) is a major cause of mortality worldwide. Children and people living with HIV (PLHIV) have an increased risk of mortality, particularly in the absence of rapid diagnosis. The main challenges of diagnosing TB in these populations are due to the unspecific and paucibacillary disease presentation and the difficulty of obtaining respiratory samples. Thus, novel diagnostic strategies, based on non-respiratory specimens could improve clinical decision making and TB outcomes in high burden TB settings. We propose a multi-country, prospective diagnostic evaluation study with a nested longitudinal cohort evaluation to assess the performance of a new stool-based qPCR, developed by researchers at Baylor College of Medicine (Houston, Texas, USA) for TB bacteriological confirmation with promising results in pilot studies. METHODS: The study will take place in high TB/HIV burden countries (Mozambique, Eswatini and Uganda) where we will enroll, over a period of 30 months, 650 PLHIV (> 15) and 1295 children under 8 years of age (irrespective of HIV status) presenting pressumptive TB. At baseline, all participants will provide clinical history, complete a physical assessment, and undergo thoracic chest X-ray imaging. To obtain bacteriological confirmation, participants will provide respiratory samples (1 for adults, 2 in children) and 1 stool sample for Xpert Ultra MTB/RIF (Cepheid, Sunnyvale, CA, USA). Mycobacterium tuberculosis (M.tb) liquid culture will only be performed in respiratory samples and lateral flow lipoarabinomannan (LF-LAM) in urine following WHO recommendations. Participants will complete 2 months follow-up if they are not diagnosed with TB, and 6 months if they are. For analytical purposes, the participants in the pediatric cohort will be classified into "confirmed tuberculosis", "unconfirmed tuberculosis" and "unlikely tuberculosis". Participants of the adult cohort will be classified as "bacteriologically confirmed TB", "clinically diagnosed TB" or "not TB". We will assess accuracy of the novel qPCR test compared to bacteriological confirmation and Tb diagnosis irrespective of laboratory results. Longitudinal qPCR results will be analyzed to assess its use as treatment response monitoring. DISCUSSION: The proposed stool-based qPCR is an innovation because both the strategy of using a non-sputum based sample and a technique specially designed to detect M.tb DNA in stool. PROTOCOL REGISTRATION DETAILS: ClinicalTrials.gov Identifier: NCT05047315.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Adulto , Criança , Humanos , Essuatíni , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Moçambique , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Sensibilidade e Especificidade , Tuberculose/diagnóstico , Tuberculose Pulmonar/diagnóstico , Uganda
17.
Bone ; 182: 117051, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38382701

RESUMO

Areal bone mineral density (aBMD) currently represents the clinical gold standard for hip fracture risk assessment. Nevertheless, it is characterised by a limited prediction accuracy, as about half of the people experiencing a fracture are not classified as at being at risk by aBMD. In the context of a progressively ageing population, the identification of accurate predictive tools would be pivotal to implement preventive actions. In this study, DXA-based statistical models of the proximal femur shape, intensity (i.e., density) and their combination were developed and employed to predict hip fracture on a retrospective cohort of post-menopausal women. Proximal femur shape and pixel-by-pixel aBMD values were extracted from DXA images and partial least square (PLS) algorithm adopted to extract corresponding modes and components. Subsequently, logistic regression models were built employing the first three shape, intensity and shape-intensity PLS components, and their ability to predict hip fracture tested according to a 10-fold cross-validation procedure. The area under the ROC curves (AUC) for the shape, intensity, and shape-intensity-based predictive models were 0.59 (95%CI 0.47-0.69), 0.80 (95%CI 0.70-0.90) and 0.83 (95%CI 0.73-0.90), with the first being significantly lower than the latter two. aBMD yielded an AUC of 0.72 (95%CI 0.59-0.82), found to be significantly lower than the shape-intensity-based predictive model. In conclusion, a methodology to assess hip fracture risk uniquely based on the clinically available imaging technique, DXA, is proposed. Our study results show that hip fracture risk prediction could be enhanced by taking advantage of the full set of information DXA contains.


Assuntos
Densidade Óssea , Fraturas do Quadril , Humanos , Feminino , Estudos Retrospectivos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/epidemiologia , Fêmur , Modelos Estatísticos , Absorciometria de Fóton/métodos
19.
PLOS Glob Public Health ; 4(2): e0002789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38335231

RESUMO

Prompt diagnosis is critical for tuberculosis (TB) control, as it enables early treatment which in turn, reduces transmission and improves treatment outcomes. We investigated the impact on TB diagnosis of introducing Xpert Ultra as the frontline diagnostic test, combined with an innovative active-case finding (ACF) strategy (based on Xpert Ultra semi-quantitative results and spatial parameters), in a semi-rural district of Southern Mozambique. From January-December 2018 we recruited incident TB-cases (index cases, ICs) and their household contacts (HCs). Recruitment of close community contacts (CCs) depended on IC´s Xpert Ultra results, and the population density of their area. TB-contacts, either symptomatic or people living with HIV, were asked to provide a spot sputum for lab-testing. Trends on TB case notification were compared to the previous years and to those of two districts in the south of the Maputo province (control area), using an interrupted time series analysis with and without control (CITS/ITS). A total of 1010 TB ICs (37.1% laboratory-confirmed) were recruited; 3165 HCs and 4730 CCs were screened for TB. Eighty-nine additional TB cases were identified through the ACF intervention (52.8% laboratory-confirmed). The intervention increased by 8.2% all forms of TB cases detected in 2018. Xpert Ultra trace positive results accounted for a high proportion of laboratory confirmations in the ACF cohort (51.1% vs 13.7% of those passively diagnosed). The Number Needed to Screen to find a TB case differed widely among HCs (55) and CCs (153). During the intervention period, a reversal of the previous negative trend in lab-confirmed case notifications was observed in the district. However, the CITS model did not show any statistically significant difference compared to the control area. Paediatric population benefited the most from the ACF strategy and HCs screening seemed an effective intervention to find microbiological confirmed cases in early stages of the disease.

20.
bioRxiv ; 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38260671

RESUMO

Objective . Intracortical microstimulation can be an effective method for restoring sensory perception in contemporary brain-machine interfaces. However, the mechanisms underlying better control of neuronal responses remain poorly understood, as well as the relationship between neuronal activity and other concomitant phenomena occurring around the stimulation site. Approach . Different microstimulation frequencies were investigated in vivo on Thy1-GCaMP6s mice using widefield and two-photon imaging to evaluate the evoked excitatory neural responses across multiple spatial scales as well as the induced hemodynamic responses. Specifically, we quantified stimulation-induced neuronal activation and depression in the mouse visual cortex and measured hemodynamic oxyhemoglobin and deoxyhemoglobin signals using mesoscopic-scale widefield imaging. Main results . Our calcium imaging findings revealed a preference for lower-frequency stimulation in driving stronger neuronal activation. A depressive response following the neural activation preferred a slightly higher frequency stimulation compared to the activation. Hemodynamic signals exhibited a comparable spatial spread to neural calcium signals. Oxyhemoglobin concentration around the stimulation site remained elevated during the post-activation (depression) period. Somatic and neuropil calcium responses measured by two-photon microscopy showed similar dependence on stimulation parameters, although the magnitudes measured in soma was greater than in neuropil. Furthermore, higher-frequency stimulation induced a more pronounced activation in soma compared to neuropil, while depression was predominantly induced in soma irrespective of stimulation frequencies. Significance . These results suggest that the mechanism underlying depression differs from activation, requiring ample oxygen supply, and affecting neurons. Our findings provide a novel understanding of evoked excitatory neuronal activity induced by intracortical microstimulation and offer insights into neuro-devices that utilize both activation and depression phenomena to achieve desired neural responses.

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