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Background: High-level expression of the Fcγ receptor, CD32hi, on CD4+ T cells was associated with enhanced human immunodeficiency virus (HIV) infection of the latent reservoir in a study of adults receiving antiretroviral therapy. We tested the hypothesis that CD32 was the preferential marker of the latent HIV reservoir in virally suppressed, perinatally HIV-infected adolescents. Methods: The frequency of CD32hiCD4+ T cells was determined by flow cytometry (N = 5) and the inducible HIV reservoir in both CD32hi and CD32-CD4+ T cells was quantified (N = 4) with a quantitative viral outgrowth assay. Viral outgrowth was measured by the standard p24 enzyme-linked immunosorbent assay and an ultrasensitive p24 assay (Simoa; Quanterix) with lower limits of quantitation. Results: We found a 59.55-fold enrichment in the absolute number of infectious cells in the CD32- population compared with CD32hi cells. Exponential HIV replication occurred exclusively in CD32-CD4+ T cells (mean change, 17.46 pg/mL; P = .04). Induced provirus in CD32hiCD4+ T cells replicated to substantially lower levels, which did not increase significantly over time (mean change, 0.026 pg/mL; P = .23) and were detected only with the Simoa assay. Conclusions: Our data suggests that the latent HIV reservoir resides mainly in CD32-CD4+ T cells in virally suppressed, perinatally HIV-infected adolescents, which has implications for reservoir elimination strategies.
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Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , Receptores de IgG/imunologia , Latência Viral/imunologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adolescente , Adulto , Antirretrovirais/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1 , Humanos , Masculino , Adulto JovemRESUMO
Monitoring human immunodeficiency virus type 1 (HIV-1) drug resistance is critical for assessing ART effectiveness and treatment outcomes for HIV-1-infected individuals, including children, worldwide. Traditionally, testing for HIV-1 drug resistance has primarily been performed on plasma samples, and with commercially available, clinically validated assays that are costly and difficult to access. While plasma is the preferred sample for HIV-1 drug resistance genotyping, plasma analysis requires sophisticated laboratory equipment, personnel, space, and stringent storage conditions for maintenance of sample integrity and transport. With the limitations in feasibility and affordability of providing these ideal conditions for plasma genotyping in resource-constrained settings, the field has gained substantial experience with the dried blood spot (DBS) technique as an alternative. Moreover, DBS analysis can be used to comprehensively monitor the spread of the epidemic with applications to more-sensitive and quantitative technologies to assess HIV-1 globally.
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HIV-1/efeitos dos fármacos , Fármacos Anti-HIV/uso terapêutico , Teste em Amostras de Sangue Seco/métodos , Farmacorresistência Viral/genética , Técnicas de Genotipagem/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/genética , Humanos , Vigilância da População/métodosRESUMO
Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis. These cells are classically defined as a subset of morphologically defined A single (As) spermatogonia, which can produce more SSCs or they can give rise to nonstem As cells that, upon replication, generate A paired (Apr) and then A aligned (Aal) spermatogonia. These latter two cell types, along with the nonstem As cells, function as transit-amplifying progenitor cells. It is known that glial cell line-derived neurotrophic factor (GDNF) is essential for maintaining all of these cells, but it is unknown if or how the responses of these cells change as they progress down the pathway to differentiated type A1 spermatogonia. We address this issue by using a chemical-genetic approach to inhibit GDNF signaling in vivo and an in vitro approach to increase GDNF stimulation. We show that inhibition for 2 days suppresses replication of As, Apr, and Aal spermatogonia to an equal extent, whereas stimulation by GDNF preferentially increases replication of As and Apr spermatogonia. We also test if inhibiting GDNF signaling causes As, Apr, and Aal spermatogonia to express Kit, an essential step in their differentiation into type A1 spermatogonia. Inhibition for 3 or 7 days produces a progressive increase in the percentages of As, Apr, and Aal undergoing differentiation, with the largest increase observed in Aal spermatogonia. Finally, we demonstrate that numbers of SSCs decrease more slowly than numbers of progenitor spermatogonia when GDNF signaling is inhibited. Taken together, these data suggest that there are significant changes in the responses to GDNF as SSCs give rise to progenitor spermatogonia, which replicate and gradually differentiate into type A1 spermatogonia.
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Células-Tronco Adultas/citologia , Células-Tronco Adultas/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Células-Tronco Adultas/fisiologia , Animais , Diferenciação Celular , Proliferação de Células , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Túbulos Seminíferos/citologia , Transdução de Sinais , Técnicas de Cultura de TecidosRESUMO
Maintaining adequate numbers of spermatogonial stem cells is required for the production of the millions of sperm required for male fertility. To date, however, the mechanisms that regulate the size of this pool in the adult are poorly defined. Glial cell line-derived neurotrophic factor (GDNF) is required for establishing this pool in the prepubertal animal, but its in vivo function in the normal adult testis has never been examined directly. We used a chemical-genetic approach to address this issue. We generated mice carrying a single amino acid mutation (V805A) in Ret, the kinase subunit of the GDNF receptor. This mutation does not affect normal GDNF signaling but renders it susceptible to inhibition by the ATP competitive inhibitor, NA-PP1. When GDNF signaling was blocked in adults for 11 days, only a few cells remained that expressed the stem spermatogonial markers, Gfrα1 and Zbtb16, and testicular Ret mRNA content was reduced markedly. These decreases were associated with depletion of functional stem spermatogonia; some were lost when GDNF signaling was inhibited for only 2 days while others survived for up to 11 days. However, when signaling was restored, the remaining stem cells proliferated, initiating tissue restoration. In conclusion, these results provide the first direct proof that GDNF acutely regulates the number of spermatogonial stem cells in the normal adult testis. Additionally, these results demonstrate different sensitivities among subpopulation of these stem cells to inhibition of GDNF signaling.
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Envelhecimento/fisiologia , Diferenciação Celular , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Transdução de Sinais , Espermatogônias/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Substituição de Aminoácidos/genética , Animais , Biomarcadores/metabolismo , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-ret/metabolismo , Espermatogônias/metabolismo , Testículo/citologia , Testículo/metabolismoRESUMO
BACKGROUND: Epilepsy is one of the most common chronic disorders of the central nervous system. The quality of life of children with epilepsy is influenced by various factors including their sleep. To assess the quality of life and sleep habits among children with epilepsy and to determine the association of QOL and sleep habits, with sociodemographic and clinical variables. MATERIALS AND METHODS: A cross-sectional study was carried out among 50 epileptic children aged 4-18 years, recruited using a convenient sampling technique from the IPDs and OPDs of the Paediatrics department of a tertiary care hospital in Eastern India. The data were collected using QOLCE-16 and CSHQ from parents of children with epilepsy. The collected data were analyzed using descriptive and inferential statistics such as ANOVA and Pearson correlation test. RESULTS: The overall mean score of QOL was 50.78 ± 17.98, with the cognitive domain having the highest mean score of 65.50 ± 27.79 and the social domain having the lowest mean score of 29.87 ± 22.81. The overall mean sleep score was found to be 56.98 ± 8.13. Daytime sleepiness, parasomnias, and bedtime resistance were found to be frequent sleep problems in children with epilepsy. There was a significant negative correlation between QOL and sleep disturbances in children with epilepsy (r = -0.65, P ≤ 0.001). CONCLUSION: The QOL of children with epilepsy should be improved to reduce the effect of sleep problems. Epilepsy children should be treated appropriately with due focus on medication compliance as it was found to be one of the determinants in improving their QOL.
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BACKGROUND: In HIV-1-exposed infants, nucleic acid testing (NAT) is required to diagnose infection since passively transferred maternal antibodies preclude antibody testing. The sensitivity of clinical NAT assays is lowered with infant antiretroviral prophylaxis and, with empiric very early antiretroviral treatment of high-risk infants, thereby impacting early infant diagnosis. Similarly, adult HIV-1 infections acquired under pre-exposure prophylaxis may occur at low levels, with undetectable plasma viremia and indeterminate antibody tests, for which HIV-1 DNA testing maybe a useful adjunct. Cell-associated HIV-1 DNA concentrations are also used to monitor HIV-1 persistence in viral reservoirs with relevance to HIV-1 cure therapeutics, particularly in perinatal infections. OBJECTIVES: We clinically validated an HIV-1 DNA quantitative assay using droplet digital PCR (ddPCR), across different HIV-1 subtypes. STUDY DESIGN: The analytical sensitivity and specificity of an HIV-1 DNA ddPCR assay was determined using serial dilutions of a plasmid containing HIV-1 LTR-gag spiked into peripheral blood mononuclear cells (PBMCs), with MOLT-4 cells or PBMCs infected with different HIV-1 subtypes (A, B and C), and U1 cells spiked into PBMCs. Inter- and intra-run variability were used to determine assay precision. RESULTS: The HIV-1 LTR-gag ddPCR assay was reliable and reproducible, and exhibited high analytical specificity with sensitivity to near single copy level, across multiple HIV-1 subtypes, and a limit of detection of 4.09 copies/million PBMCs. CONCLUSIONS: This assay has applications for detecting occult HIV-1-infection in the setting of combination and long-acting regimens used for HIV-1 prevention, across different HIV-1 subtypes, in infants and adults, and in HIV-1 cure interventions.
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Infecções por HIV , HIV-1 , Antirretrovirais/uso terapêutico , DNA Viral/genética , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Leucócitos Mononucleares , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Carga ViralRESUMO
Background Myocardial infarction and premature death have been observed in patients with psoriasis. Although inflammation-driven accelerated atherosclerosis has been proposed as a mechanism, the relationship between subclinical noncalcified coronary burden (NCB), functional coronary flow impairment, and myocardial injury is unclear. Methods and Results In an ongoing longitudinal cohort study, 202 consecutive patients with psoriasis (168 at 1 year) underwent coronary computed tomography angiography to identify coronary plaque, quantify NCB, and calculate coronary fractional flow reserve by computed tomography. Serum high-sensitivity troponin-T (hs-cTn-T) was measured using a fifth-generation assay. Overall, patients were middle-aged, predominantly male, and low cardiovascular risk. A higher than median NCB associated with a positive hs-cTn-T (fully adjusted model [odds ratio (OR), 1.72; 95% CI, 1.10-2.69, P=0.018]) at baseline. Additionally, patients with a higher than median baseline NCB had higher odds of positive hs-cTn-T at 1 year in fully adjusted analyses (adjusted OR, 2.36; 95% CI, 1.47-3.79, P<0.001). Higher NCB was associated with a higher frequency of fractional flow reserve by computed tomography ≤0.80 (36.11% versus 25.11%, Pearson χ2=6.84, P=0.009, unadjusted OR, 2.09; 95% CI, 1.36-3.22, P<0.001) and higher frequency of a positive hs-cTn-T (54.36% versus 27.54%, Pearson χ2=32.23, P<0.001) in adjusted models (OR, 2.63; 95% CI, 1.56-4.42, P<0.001). Conclusions NCB was associated with hs-cTn-T at baseline as well as at 1 year. Furthermore, patients with high NCB had higher prevalence of fractional flow reserve by computed tomography ≤0.80 and a >2- fold higher odds of positive hs-cTn-T. These findings underscore the importance of early vascular disease in driving myocardial injury, and support conduct of myocardial perfusion studies to better understand these findings.
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Doença da Artéria Coronariana/epidemiologia , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Psoríase/complicações , Adulto , Angiografia por Tomografia Computadorizada , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Psoríase/sangue , Psoríase/diagnóstico por imagem , Troponina T/sangueRESUMO
Injury or damage to tissue and organs is a major health problem, resulting in about half of the world's annual healthcare expenditure every year. Advances in the fields of stem cells (SCs) and biomaterials processing have provided a tremendous leap for researchers to manipulate the dynamics between these two, and obtain a skin substitute that can completely heal the wounded areas. Although wound healing needs a coordinated interplay between cells, extracellular proteins and growth factors, the most important players in this process are the endogenous SCs, which activate the repair cascade by recruiting cells from different sites. Extra cellular matrix (ECM) proteins are activated by these SCs, which in turn aid in cellular migrations and finally secretion of growth factors that can seal and heal the wounds. The interaction between ECM proteins and SCs helps the skin to sustain the rigors of everyday activity, and in an attempt to attain this level of functionality in artificial three-dimensional (3D) constructs, tissue engineered biomaterials are fabricated using more advanced techniques such as bioprinting and laser assisted printing of the organs. This review provides a concise summary of the most recent advances that have been made in the area of polymer bio-fabrication using 3D bio printing used for encapsulating stem cells for skin regeneration. The focus of this review is to describe, in detail, the role of 3D architecture and arrangement of cells within this system that can heal wounds and aid in skin regeneration.
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Ehlers-Danlos syndrome (EDS) is a generalized disorder of one element of connective tissue manifesting clinically by fragility and hyperelasticity of the skin and joint laxity. It is a hereditary disorder, the inheritance being usually autosomal dominant with low penetrance. Autosomal recessive and X-linked recessive varieties are also known. First described by Hippocrates in 4(th) century B.C., the various clinical types with variable penetrance have been described lately. The number of cases EDS reported in the literature is very meagre. With the available information only about six publications of classic EDS in siblings had been reported in Indian literature.
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Nanostructured biomimetics have recently shown great promise in the field of tissue engineering. They can be used as nanoscaffolds and tailored at the molecular level. The scaffold topography closely resembles the native extracellular matrix in terms of framing, porosity and bio-functionality. This review covers the approaches used for biomimetic fabrication, including soft lithography, the plasmonic nanohybrid matrix method and multilayer self-assembly scaffolds for tissue regeneration. It brings together knowledge from different arenas about the synthesis, characterization and functionalization of matrices to accelerate the tissue regeneration process. Every tissue in the body presents different challenges and requires a specific fabrication process designed to identify and mirror the particular organ. For example, microfluidics systems aim to mimic the extracellular matrix of vascular and cartilage tissue, and these systems have different parts with completely different mechanical strength, cellular adhesion and interplay between matrix and cells. A fully functional nanomatrix designed by a self-assembling methodology for use as a vascular tissue engineering scaffold needs to have intrinsic microvessels that facilitate the transportation of metabolites and nutrients. Similarly, in the case of peripheral nerve regeneration, a scaffold needs to have sufficient mechanical strength to protect the regenerating tissue, yet be biodegradable enough to avoid a possible second surgery. To enhance the functionality of scaffolds, increasing focus has been placed on in vitro and in vivo research to achieve optimal scaffold design. Nanobiomimetics unarguably offer the most suitable physicochemical scaffold properties for tissue regeneration.
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Materiais Biomiméticos/farmacologia , Nanopartículas/química , Regeneração/efeitos dos fármacos , Animais , Humanos , Nanofibras , Pontos Quânticos/química , Alicerces Teciduais/químicaRESUMO
Engineering three-dimensional (3-D) porous scaffolds with precise bio-functional properties is one of the most important issues in tissue engineering. In the present study, a three-dimensional gelatin-hyaluronic acid-alginate (GHA) polymeric composite was synthesized by freeze-drying, which was followed by ionic crosslinking using CaCl2, and evaluated for its suitability in bone tissue engineering applications. The obtained matrix showed high porosity (85%), an interconnected pore morphology and a rapid swelling behavior. The rheological analysis of GHA showed a viscoelastic characteristic, which suggested a high load bearing capacity without fractural deformation. The influence of the GHA matrix on cell growth and on modulating the differentiation ability of mesenchymal stem cells was evaluated by different biochemical and immunostaining assays. The monitoring of cells over a period of four weeks showed increased cellular proliferation and osteogenic differentiation without external growth factors, compared with control (supplemented with osteogenic differentiation medium). The in vivo matrix implantation showed higher matrix-tissue integration and cell infiltration as the duration of the implant increased. These results suggest that a porous GHA matrix with suitable mechanical integrity and tissue compatibility is a promising substrate for the osteogenic differentiation of stem cells for bone tissue engineering applications.
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Alginatos/química , Gelatina/química , Ácido Hialurônico/química , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
Terminalia chebula is one of the traditional medicines used in the treatment of many diseases. In the present work, different concentrations of various organic and aqueous extracts (solvent-free) of T. chebula were tested on fibroblast (L929) and keratinocytes cells to evaluate its biocompatible concentration by using MTT and live-dead viability/cytotoxic assay. These extracts were found to be effective in decreasing the ammonia accumulation in the media, thereby reducing its toxic effect on cells. DPPH assay further confirmed the free-radical scavenging ability of the extracts which increased with the increase in concentration of each extract. Cell proliferation/apoptosis, cytoskeletal structure, and ECM production were further evaluated by live-dead assay and phalloidin/cytokeratin staining, respectively. The cytoskeletal structure and ECM secretion of the cells treated with extracts showed higher cellular activity in comparison to control. In conclusion, we have demonstrated the effect of these extracts of T. chebula on both types of skin cells and optimized concentration in which it could be used as a bioactive component for wound healing applications by increasing cell proliferation and decreasing free-radical production without affecting the normal cellular matrix. It can also find applications in other therapeutics applications where ammonia toxicity is a limiting factor.