Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
J Immunol ; 204(4): 819-831, 2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-31900339

RESUMEN

IL-3, a cytokine secreted by activated T lymphocytes, is known to regulate the proliferation, survival, and differentiation of hematopoietic cells. However, the role of IL-3 in regulation of T cell functions is not fully delineated. Previously, we have reported that IL-3 plays an important role in development of regulatory T cells in mice. In this study, we investigated the regulation of IL-3R expression on human Th cells and also examined the role of IL-3 in effector functions of these cells. We found that human peripheral blood Th cells in resting state do not show surface expression of IL-3R; however, its expression was observed at transcript and intracellular protein levels. The functional IL-3R expression on the surface was seen only after antigenic stimulation. When naive Th cells were activated in the presence of various cytokines, we found that IL-4 significantly increases the surface expression of IL-3R and also increases the number of IL-3R+ Th cells. Interestingly, IL-3R+ cells exhibit a Th2 cell-like phenotype and show high GATA-3 expression. Moreover, Th2 cells in presence of IL-3 show increased expression of type 2 effector cytokines, such as IL-4, IL-5, and IL-13. Furthermore, IL-3R expressing and IL-3-secreting Th cells were high in house dust mite-allergic patients. Thus, to our knowledge, we provide the first evidence that the expression of IL-3R on activated human Th cells is modulated by IL-4, and IL-3 regulates the effector functions of Th2 cells. Our results suggest that IL-3 may play an important role in regulating allergic immune responses.


Asunto(s)
Diferenciación Celular/inmunología , Interleucina-3/inmunología , Interleucina-4/inmunología , Receptores de Interleucina-3/inmunología , Células Th2/inmunología , Humanos , Hipersensibilidad/inmunología , Interleucina-3/metabolismo , Interleucina-4/metabolismo , Activación de Linfocitos/inmunología , Receptores de Interleucina-3/metabolismo
2.
Toxicol Pathol ; 49(4): 872-887, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33252007

RESUMEN

In preclinical toxicology studies, a "stage-aware" histopathological evaluation of testes is recognized as the most sensitive method to detect effects on spermatogenesis. A stage-aware evaluation requires the pathologist to be able to identify the different stages of the spermatogenic cycle. Classically, this evaluation has been performed using periodic acid-Schiff (PAS)-stained sections to visualize the morphology of the developing spermatid acrosome, but due to the complexity of the rat spermatogenic cycle and the subtlety of the criteria used to distinguish between the 14 stages of the cycle, staging of tubules is not only time consuming but also requires specialized training and practice to become competent. Using different criteria, based largely on the shape and movement of the elongating spermatids within the tubule and pooling some of the stages, it is possible to stage tubules using routine hematoxylin and eosin (H&E)-stained sections, thereby negating the need for a special PAS stain. These criteria have been used to develop an automated method to identify the stages of the rat spermatogenic cycle in digital images of H&E-stained Wistar rat testes. The algorithm identifies the spermatogenic stage of each tubule, thereby allowing the pathologist to quickly evaluate the testis in a stage-aware manner and rapidly calculate the stage frequencies.


Asunto(s)
Aprendizaje Profundo , Testículo , Animales , Eosina Amarillenta-(YS) , Hematoxilina , Humanos , Masculino , Ratas , Ratas Wistar , Espermatogénesis
3.
Sleep Breath ; 25(2): 737-748, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32865729

RESUMEN

PURPOSE: In recent years, point-of-care (POC) devices, especially smart wearables, have been introduced to provide a cost-effective, comfortable, and accessible alternative to polysomnography (PSG)-the current gold standard-for the monitoring, screening, and diagnosis of obstructive sleep apnea (OSA). Thorough validation and human subject testing are essential steps in the translation of these device technologies to the market. However, every device development group tests their device in their own way. No standard guidelines exist for assessing the performance of these POC devices. The purpose of this paper is to critically distill the key aspects of the various protocols reported in the literature and present a protocol that unifies the best practices for testing wearable and other POC devices for OSA. METHODS: A limited review and graphical descriptive analytics of literature-including journal articles, web sources, and clinical manuscripts by authoritative agencies in sleep medicine-are performed to glean the testing and validation methods employed for POC devices, specifically for OSA. RESULTS: The analysis suggests that the extent of heterogeneity of the demographics, the performance metrics, subject survey, hypotheses, and statistical analyses need to be carefully considered in a systematic protocol for testing POC devices for OSA. CONCLUSION: We provide a systematic method and list specific recommendations to extensively assess various performance criteria for human subject testing of POC devices. A rating scale of 1-3 is provided to encourage studies to put a focus on addressing the key elements of a testing protocol.


Asunto(s)
Pruebas en el Punto de Atención/normas , Apnea Obstructiva del Sueño/diagnóstico , Humanos
4.
J Immunol ; 195(11): 5136-48, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26538398

RESUMEN

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammatory synovitis leading to joint destruction and systemic bone loss. The inflammation-induced bone loss is mediated by increased osteoclast formation and function. Current antirheumatic therapies primarily target suppression of inflammatory cascade with limited or no success in controlling progression of bone destruction. Mesenchymal stem cells (MSCs) by virtue of their tissue repair and immunomodulatory properties have shown promising results in various autoimmune and degenerative diseases. However, the role of MSCs in prevention of bone destruction in RA is not yet understood. In this study, we investigated the effect of adipose-derived MSCs (ASCs) on in vitro formation of bone-resorbing osteoclasts and pathological bone loss in the mouse collagen-induced arthritis (CIA) model of RA. We observed that ASCs significantly inhibited receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis in both a contact-dependent and -independent manner. Additionally, ASCs inhibited RANKL-induced osteoclastogenesis in the presence of proinflammatory cytokines such as TNF-α, IL-17, and IL-1ß. Furthermore, treatment with ASCs at the onset of CIA significantly reduced clinical symptoms and joint pathology. Interestingly, ASCs protected periarticular and systemic bone loss in CIA mice by maintaining trabecular bone structure. We further observed that treatment with ASCs reduced osteoclast precursors in bone marrow, resulting in decreased osteoclastogenesis. Moreover, ASCs suppressed autoimmune T cell responses and increased the percentages of peripheral regulatory T and B cells. Thus, we provide strong evidence that ASCs ameliorate inflammation-induced systemic bone loss in CIA mice by reducing osteoclast precursors and promoting immune tolerance.


Asunto(s)
Artritis Experimental/inmunología , Artritis Reumatoide/inmunología , Resorción Ósea/inmunología , Células Madre Mesenquimatosas/inmunología , Osteoclastos/inmunología , Ligando RANK/antagonistas & inhibidores , Tejido Adiposo/citología , Animales , Artritis Experimental/patología , Artritis Reumatoide/patología , Autoinmunidad/inmunología , Linfocitos B/inmunología , Huesos/inmunología , Huesos/patología , Diferenciación Celular/inmunología , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Tolerancia Inmunológica/inmunología , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Recuento de Linfocitos , Masculino , Ratones , Ratones Endogámicos DBA , Linfocitos T Reguladores/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
5.
Biochem Biophys Res Commun ; 455(1-2): 133-8, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25450704

RESUMEN

The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (µ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet.


Asunto(s)
Densidad Ósea , Dieta Alta en Grasa , Obesidad/etiología , Animales , Huesos/diagnóstico por imagen , Dieta Alta en Grasa/efectos adversos , Masculino , Radiografía , Ratas , Ratas Wistar
6.
J Food Sci Technol ; 51(10): 2508-16, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25328190

RESUMEN

Enzymes have been the centre of attention for researchers/industrialists worldwide due to their wide range of physiological, analytical, food/feed and industrial based applications. Among the enzymes explored for industrial applications, xylanases play an instrumental role in food/feed, textile/detergent, paper and biorefinery based application sectors. This study deals with the statistical optimization of xylanase production by Thielaviopsis basicola MTCC 1467 under submerged fermentation conditions using rice straw, as sole carbon source. Different fermentation parameters such as carbon source, nitrogen source, inorganic salts like KH2PO4, MgSO4 and pH of the medium were optimized at the individual and interactive level by Taguchi orthogonal array methodology (L16). All selected fermentation parameters influenced the enzyme production. Rice straw, the major carbon source mainly influenced the production of xylanase (~34 %). After media optimization, the yield of enzyme improved from 38 to ~60 IU/ml (161.5 %) indicating the commercial production of xylanase by T. basicola MTCC 1467. This study shows the potential of T. basicola MTCC 1467 for the efficient xylanase production under the optimized set of conditions.

7.
Indian J Dent Res ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39171687

RESUMEN

ABSTRACT: Trichofolliculoma is a rare benign, hamartomatous adnexal tumour of the skin. Aetiology seems to be unclear. It is usually seen in adults, with no gender predilection. The most commonly involved sites are the face and scalp. It appears as a papule or nodule with small protruding hairs, which is a classic feature of the tumour. It has unique diagnostic and histopathological features that help in making a definitive diagnosis. Here, we report an exemplary case of an adult male patient aged 45 years with a gradual progressive diffuse swelling on the left side of the face for 1.5 years. Clinically, it was diagnosed as a sebaceous cyst, but after the biopsy histopathological evaluation was performed, and the diagnosis was confirmed as trichofolliculoma.

8.
J Immunol ; 186(4): 2262-72, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21242512

RESUMEN

IL-3, a cytokine secreted by Th cells, functions as a link between the immune and the hematopoietic system. We previously demonstrated the potent inhibitory role of IL-3 on osteoclastogenesis, pathological bone resorption, and inflammatory arthritis. In this study, we investigated the novel role of IL-3 in development of regulatory T (Treg) cells. We found that IL-3 in a dose-dependent manner increases the percentage of Foxp3(+) Treg cells indirectly through secretion of IL-2 by non-Treg cells. These IL-3-expanded Treg cells are competent in suppressing effector T cell proliferation. Interestingly, IL-3 treatment significantly reduces the severity of arthritis and restores the loss of Foxp3(+) Treg cells in thymus, lymph nodes, and spleen in collagen-induced arthritis mice. Most significantly, we show that IL-3 decreases the production of proinflammatory cytokines IL-6, IL-17A, TNF-α, and IL-1 and increases the production of anti-inflammatory cytokines IFN-γ and IL-10 in collagen-induced arthritis mice. Thus, to our knowledge, we provide the first evidence that IL-3 play an important role in modulation of Treg cell development in both in vitro and in vivo conditions, and we suggest its therapeutic potential in the treatment of rheumatoid arthritis and other autoimmune diseases.


Asunto(s)
Artritis Experimental/inmunología , Artritis Experimental/terapia , Diferenciación Celular/inmunología , Colágeno/administración & dosificación , Factores de Transcripción Forkhead/biosíntesis , Interleucina-3/uso terapéutico , Linfocitos T Reguladores/inmunología , Animales , Artritis Experimental/patología , Artritis Reumatoide/inmunología , Artritis Reumatoide/patología , Artritis Reumatoide/terapia , Interleucina-3/administración & dosificación , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Linfocitos T Reguladores/patología
9.
Artif Intell Med ; 145: 102685, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37925216

RESUMEN

Reflectance-based photoplethysmogram (PPG) sensors provide flexible options of measuring sites for blood oxygen saturation (SpO2) measurement. But they are mostly limited by accuracy, especially when applied to different subjects, due to the diverse human characteristics (skin colors, hair density, etc.) and usage conditions of different sensor settings. This study addresses the estimation of SpO2 at non-standard measuring sites employing reflectance-based sensors. It proposes an automated construction of subject inclusion-exclusion criteria for SpO2 measuring devices, using a combination of unsupervised clustering, supervised regression, and model explanations. This is perhaps among the first adaptation of SHAP to explain the clusters gleaned from unsupervised learning methods. As a wellness application case study, we developed a pillow-based wearable device to collect reflectance PPGs from both the brachiocephalic and carotid arteries around the neck. The experiment was conducted on 33 subjects, each under totally 80 different sensor settings. The proposed approach addressed the variations of humans and devices, as well as the heterogeneous mapping between signals and SpO2 values. It identified effective device settings and characteristics of their applicable subject groups (i.e., subject inclusion-exclusion criteria). Overall, it reduced the root mean squared error (RMSE) by 16%, compared to an empirical formula and a plain SpO2 estimation model.


Asunto(s)
Oxígeno , Fotopletismografía , Humanos , Fotopletismografía/métodos , Oximetría/métodos , Aprendizaje Automático
10.
J Oral Maxillofac Pathol ; 27(3): 489-493, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38033976

RESUMEN

Introduction: Despite advances in diagnostics and therapeutics, two-thirds of oral cancer patients present with advanced disease, which increases both the morbidity and mortality risk. Circulating tumour cells (CTCs) are released in the circulation by primary tumours and have been demonstrated to have significant correlations between their occurrence and disease progression. Objectives: To characterize the circulating tumour cells in subjects with histologically diagnosed oral squamous cell carcinoma (OSCC). Materials and Methods: This pilot study was undertaken with ten fresh blood samples (6 ml each). Five samples from apparently healthy individuals and five OSCC samples were cultured and subjected to flow cytometric analysis for CD44 expression. Immunostaining was done using CD44 and EpCAM markers. Result: Several cells in OSCC samples showed EpCAM and CD44 positivity following immunostaining. However, flow cytometry performed with CD44 alone was not specific for OSCC samples. Hence, proving that CD44 and EpCAM when used in conjunction can help to characterize CTCs. Conclusion: The findings of our study suggest that the demonstration of CTCs is feasible and helps in understanding of disease progression and metastatic risk. Sensitive detection of CTCs from blood samples can serve as an implicit tool in early cancer diagnosis and prognosis through liquid biopsy which in itself is minimally invasive and time-saving.

11.
Biochem Biophys Res Commun ; 418(4): 669-75, 2012 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-22293197

RESUMEN

IL-3 is an important cytokine that regulates hematopoiesis. We have previously demonstrated that IL-3 is a potent inhibitor of osteoclastogenesis and bone resorption. In the present study, we have investigated the role of IL-3 on human osteoblast differentiation and bone formation. We found that IL-3 in a dose-dependent manner increases osteoblast differentiation and matrix mineralization in human mesenchymal stem cells (MSCs). IL-3 significantly enhances the expression of osteoblast specific genes such as alkaline phosphatase, collagen type-I, osteocalcin and osteopontin; and Runx-2 and osterix transcription factors. Moreover, IL-3 induces the expression of bone morphogenetic protein-2 (BMP-2), and activates smad1/5/8. IL-3 enhances osteoblast differentiation and BMP-2 secretion through JAK/STAT pathway. Interestingly, IL-3 promotes in vivo bone regeneration ability of MSCs. Thus, we reveal for the first time that IL-3 enhances human osteoblast differentiation and bone formation in both in vitro and in vivo conditions, and suggest its therapeutic potential for bone formation in important bone diseases.


Asunto(s)
Diferenciación Celular , Interleucina-3/fisiología , Células Madre Mesenquimatosas/citología , Osteoblastos/citología , Osteogénesis , Fosfatasa Alcalina/biosíntesis , Animales , Proteína Morfogenética Ósea 2/biosíntesis , Regeneración Ósea , Colágeno Tipo I/biosíntesis , Subunidad alfa 1 del Factor de Unión al Sitio Principal/biosíntesis , Humanos , Interleucina-3/farmacología , Subunidad alfa del Receptor de Interleucina-3/biosíntesis , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Osteocalcina/biosíntesis , Osteopontina/biosíntesis , Factor de Transcripción Sp7 , Factores de Transcripción/biosíntesis
12.
J Immunol ; 185(4): 2261-72, 2010 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-20644169

RESUMEN

IL-3 is an important cytokine that regulates hematopoiesis and functions as a link between the immune and the hematopoietic system. In this study, we investigated the role and mechanism of IL-3 action on human osteoclast formation and bone resorption using PBMCs. PBMCs differentiate into functional osteoclasts in the presence of M-CSF and receptor activator of NF-kappaB ligand as evaluated by 23c6 expression and bone resorption. We found that IL-3 dose-dependently inhibited formation of 23c6-positive osteoclasts, bone resorption and C-terminal telopeptide of type I collagen, a collagen degradation product. The inhibitory effect of IL-3 on bone resorption was irreversible. To investigate the mechanism of IL-3 action, we analyzed the effect of IL-3 on the receptor activator of NF-kappaB and c-Fms receptors and c-Fos, PU.1, NFAT cytoplasmic 1, and RelB transcription factors essential for osteoclastogenesis. IL-3 significantly inhibited c-Fms and downregulated both PU.1 and c-Fos at both mRNA and protein level. Furthermore, IL-3-treated cells showed increased expression of dendritic cell markers CD1a and CD80 and decreased expression of monocyte/macrophage marker CD14. Interestingly, IL-3 inhibited formation of human osteoclasts derived from blood monocytes and bone marrow cells of osteoporotic individuals. Thus, IL-3 may have therapeutic potential as an antiosteolytic agent in treatment of osteoporosis.


Asunto(s)
Células Dendríticas/efectos de los fármacos , Interleucina-3/farmacología , Osteoclastos/efectos de los fármacos , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Adulto , Anciano , Resorción Ósea/prevención & control , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/metabolismo , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Citometría de Flujo , Expresión Génica/efectos de los fármacos , Humanos , Persona de Mediana Edad , Osteoclastos/citología , Osteoclastos/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligando RANK/farmacología , Receptor de Factor Estimulante de Colonias de Macrófagos/genética , Receptores de Interleucina-3/genética , Receptores de Interleucina-3/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven
13.
Sensors (Basel) ; 12(8): 10851-70, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23112633

RESUMEN

This paper presents the design and testing of a wireless sensor system developed using a Microchip PICDEM developer kit to acquire and monitor human heart sounds for phonocardiography applications. This system can serve as a cost-effective option to the recent developments in wireless phonocardiography sensors that have primarily focused on Bluetooth technology. This wireless sensor system has been designed and developed in-house using off-the-shelf components and open source software for remote and mobile applications. The small form factor (3.75 cm × 5 cm × 1 cm), high throughput (6,000 Hz data streaming rate), and low cost ($13 per unit for a 1,000 unit batch) of this wireless sensor system make it particularly attractive for phonocardiography and other sensing applications. The experimental results of sensor signal analysis using several signal characterization techniques suggest that this wireless sensor system can capture both fundamental heart sounds (S1 and S2), and is also capable of capturing abnormal heart sounds (S3 and S4) and heart murmurs without aliasing. The results of a denoising application using Wavelet Transform show that the undesirable noises of sensor signals in the surrounding environment can be reduced dramatically. The exercising experiment results also show that this proposed wireless PCG system can capture heart sounds over different heart conditions simulated by varying heart rates of six subjects over a range of 60-180 Hz through exercise testing.


Asunto(s)
Fonocardiografía/instrumentación , Fonocardiografía/métodos , Telemedicina/instrumentación , Tecnología Inalámbrica/instrumentación , Humanos , Análisis de Ondículas
14.
J Immunol ; 182(1): 361-70, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19109167

RESUMEN

IL-3, a cytokine secreted by activated T cells is well known to regulate the proliferation, differentiation, and survival of pluripotent hematopoietic stem cells. IL-3 functions as a link between the immune and the hematopoietic system. In this study, we suggest an important new role of IL-3 in inhibition of TNF-alpha-induced bone resorption in vitro and prevention of inflammatory arthritis in mice. We show here that IL-3 potently and irreversibly inhibits TNF-alpha-induced bone resorption in hematopoietic precursors of monocyte/macrophage lineage. IL-3 showed an inhibitory effect on TNF-alpha-induced bone resorption even in the presence of proinflammatory cytokines such as IL-1alpha, TGF-beta(1), TGF-beta(3), IL-6, and PGE(2). We found that IL-3 prevented TNF-alpha-induced c-fos nuclear translocation and AP-1 DNA-binding activity. Interestingly, IL-3 pretreatment prevented the development of inflammatory arthritis in mice induced by a mixture of anti-type II collagen mAbs and LPS. Furthermore, IL-3 prevented cartilage and bone loss in the joints indirectly through inhibition of inflammation. Thus, we provide the first evidence that IL-3, a strong regulator of hematopoiesis, also plays an important role in inhibition of TNF-alpha-induced bone resorption and prevention of inflammatory arthritis in mice.


Asunto(s)
Artritis Experimental/inmunología , Artritis Experimental/prevención & control , Resorción Ósea/inmunología , Resorción Ósea/prevención & control , Mediadores de Inflamación/fisiología , Interleucina-3/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Transporte Activo de Núcleo Celular/inmunología , Animales , Anticuerpos Monoclonales/administración & dosificación , Artritis Experimental/metabolismo , Resorción Ósea/patología , Cartílago Articular/inmunología , Cartílago Articular/metabolismo , Cartílago Articular/patología , Núcleo Celular/inmunología , Núcleo Celular/metabolismo , Células Cultivadas , Colágeno Tipo II/inmunología , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/metabolismo , Mediadores de Inflamación/administración & dosificación , Interleucina-3/administración & dosificación , Lipopolisacáridos/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Técnicas de Cultivo de Órganos , Osteocondritis/inmunología , Osteocondritis/metabolismo , Osteocondritis/prevención & control , Unión Proteica/genética , Unión Proteica/inmunología , Proteínas Proto-Oncogénicas c-fos/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-fos/metabolismo , Factor de Transcripción AP-1/antagonistas & inhibidores , Factor de Transcripción AP-1/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
15.
Biochem Biophys Res Commun ; 399(4): 688-93, 2010 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-20691668

RESUMEN

IL-3, a cytokine secreted by activated T lymphocytes, stimulates the proliferation, differentiation and survival of pluripotent hematopoietic stem cells. In this study, we investigated the mechanism of inhibitory action of IL-3 on osteoclast differentiation. We show here that IL-3 significantly inhibits receptor activator of NF-kappaB (RANK) ligand (RANKL)-induced activation of c-Jun N-terminal kinase (JNK). IL-3 down-regulates expression of c-Fos and nuclear factor of activated T cells (NFATc1) transcription factors. In addition, IL-3 down-regulates RANK expression posttranscriptionally in both purified osteoclast precursors and whole bone marrow cells. Furthermore, the inhibitory effect of IL-3 on RANK expression was irreversible. Interestingly, IL-3 inhibits in vivo RANK expression in mice. Thus, we provide the first evidence that IL-3 irreversibly inhibits RANK expression that results in inhibition of important signaling molecules induced by RANKL.


Asunto(s)
Diferenciación Celular , Interleucina-3/metabolismo , Osteoclastos/citología , Ligando RANK/metabolismo , Receptor Activador del Factor Nuclear kappa-B/biosíntesis , Animales , Células de la Médula Ósea/citología , Células Cultivadas , Interleucina-3/farmacología , MAP Quinasa Quinasa 4/antagonistas & inhibidores , MAP Quinasa Quinasa 4/biosíntesis , Ratones , Factores de Transcripción NFATC/metabolismo , Osteoclastos/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Receptor Activador del Factor Nuclear kappa-B/antagonistas & inhibidores
16.
Biochem Biophys Res Commun ; 393(3): 377-83, 2010 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-20138833

RESUMEN

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into multiple cell lineages. Presently, bone marrow is considered as a prime source of MSCs; however, there are some drawbacks and limitations in use of these MSCs for cell therapy. In this study, we demonstrate that human gingival tissue-derived MSCs have several advantages over bone marrow-derived MSCs. Gingival MSCs are easy to isolate, homogenous and proliferate faster than bone marrow MSCs without any growth factor. Importantly, gingival MSCs display stable morphology and do not loose MSC characteristic at higher passages. In addition, gingival MSCs maintain normal karyotype and telomerase activity in long-term cultures, and are not tumorigenic. Thus, we reveal that human gingiva is a better source of MSCs than bone marrow, and large number of functionally competent clinical grade MSCs can be generated in short duration for cell therapy in regenerative medicine and tissue engineering.


Asunto(s)
Separación Celular/métodos , Encía/citología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Células de la Médula Ósea/fisiología , Regeneración Ósea , Diferenciación Celular , Transformación Celular Neoplásica , Humanos , Cariotipificación , Medicina Regenerativa
17.
Infect Drug Resist ; 13: 1133-1145, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32368104

RESUMEN

INTRODUCTION: Species of genus Candida are part of the common microbiota of humans; however, some of the Candida species are known opportunistic pathogens. Formation of biofilms, resistance to antifungal drugs, and increase in asymptomatic infections demands more studies on isolation, identification and characterization of Candida from clinical samples. METHODS: The present manuscript deals with assessment of authentic yeast identification by three methods viz., DNA sequencing of 28S rRNA gene, protein profiles using MALDI-TOF MS, and colony coloration on chromogenic media. Antifungal susceptibility and in vitro cell invasion assays were performed to further characterize these isolates. RESULTS: Comparison of three methods showed that DNA sequence analysis correctly identified more than 99.4% of the isolates up to species level as compared to 89% by MALDI-TOF MS. In this study, we isolated a total of 176 yeasts from clinical samples and preliminary morphological characters indicated that these yeast isolates belong to the genus Candida. The species distribution of isolates was as follows: 75 isolates of Candida albicans (42.61%), 50 of C. tropicalis (28.40%), 22 of C. glabrata (12.5%), 14 of C. parapsilosis (7.95%) and 4 of Clavispora lusitaniae (2.27%). Other species like Cyberlindnera fabianii, Issatchenkia orientalis, Kluyveromyces marxianus, Kodamaea ohmeri, Lodderomyces sp., and Trichosporon asahii were less than 2%. Antifungal susceptibility assay performed with 157 isolates showed that most of the isolates were resistant to the four azoles viz., clotrimazole, fluconazole, itraconazole, and ketoconazole, and the frequency of resistance was more in non-albicans Candida isolates. The susceptibility to azole drugs ranged from 7% to 48%, while 75% of the tested yeasts were susceptible to nystatin. Moreover, 88 isolates were also tested for their capacity to invade human cells using HeLa cells. In vitro invasion assay showed that most of the C. albicans isolates showed epithelial cell invasion as compared to isolates belonging to C. glabrata, C. parapsilosis and C. tropicalis. DISCUSSION: The identification of yeasts of clinical origin by sequencing of 28S rRNA gene performed better than MALDI-TOF MS. The present study reiterates the world scenario wherein there is a shift from Candida strains to emerging opportunistic pathogens which were earlier regarded as environmental strains. The present study enlightens the current understanding of identification methods for clinical yeast isolates, increased antifungal drug resistance, epithelial cell invasion as a virulence factor, and diversity of yeasts in Indian clinical samples.

18.
J Electrocardiol ; 42(6): 622-30, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19608193

RESUMEN

BACKGROUND: Recent advances in computer graphics and wireless technologies have renewed interest in vectorcardiogram (VCG) signals that use fewer leads than the conventional 12-lead electrocardiogram (ECG) signals for medical diagnostic applications. However, most cardiologists are accustomed to the 12-lead ECG even though some of the leads are either nearly aligned with or derived from the others and consequently contain redundant information. The ability to transform from orthogonal 3-lead VCG to 12-lead ECG enables the use of fewer leads for signal analysis, computer visualization, and wireless transmission of signals. This can also improve mobility, albeit limited, to the patients. MATERIALS AND METHODS: We present a statistical approach to transform 3-lead Frank VCG to 12-lead ECG signals and vice versa, based on Dower's pioneering work on lead transformation. This approach enables compensation of baseline shifts and other constant biases present in long ECG data streams, so that the resulting statistical transforms can be more consistent and accurate. We compare the performance of the affine transform with that of Dower transform (from 3 to 12 and from 12 to 3) using the data from the PhysioNet PTB database. RESULTS: The results show that for both myocardial infarction (MI) and healthy control (HC) subjects, the statistical affine transform presented here maps 3-lead VCG to12-lead ECG more accurately than Dower or other lead transformation matrices of the ECG recordings. DISCUSSION: This investigation also shows the limitations associated with single dipole assumption that underlies Dower's geometric transformation. The results also indicate that lead transformation accuracy can be improved using separate customized transforms to, for example, age or pathologic conditions (here, MI vs HC) than a single statistical or geometric transform. Pertinently, we find that the affine transform coefficients can serve as discriminating features for classification/discrimination of MI patients from HC subjects.


Asunto(s)
Algoritmos , Arritmias Cardíacas/diagnóstico , Diagnóstico por Computador/métodos , Vectorcardiografía/métodos , Interpretación Estadística de Datos , Humanos , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Biomed Eng Lett ; 9(2): 221-231, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31168427

RESUMEN

Brain disorder recognition has becoming a promising area of study. In reality, some disorders share similar features and signs, making the task of diagnosis and treatment challenging. This paper presents a rigorous and robust computer aided diagnosis system for the detection of multiple brain abnormalities which can assist physicians in the diagnosis and treatment of brain diseases. In this system, we used energy of wavelet sub bands, textural features of gray level co-occurrence matrix and intensity feature of MR brain images. These features are ranked using Wilcoxon test. The composite features are classified using back propagation neural network. Bayesian regulation is adopted to find the optimal weights of neural network. The experimentation is carried out on datasets DS-90 and DS-310 of Harvard Medical School. To enhance the generalization capability of the network, fivefold stratified cross validation technique is used. The proposed system yields multi class disease classification accuracy of 100% in differentiating 90 MR brain images into 18 classes and 97.81% in differentiating 310 MR brain images into 6 classes. The experimental results reveal that the composite features along with BPNN classifier create a competent and reliable system for the identification of multiple brain disorders which can be used in clinical applications. The Wilcoxon test outcome demonstrates that standard deviation feature along with energies of approximate and vertical sub bands of level 7 contribute the most in achieving enhanced multi class classification performance results.

20.
Sci Rep ; 9(1): 10617, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31337808

RESUMEN

We present experimental evidence for a new mechanism for how smooth surfaces emerge during repetitive sliding contacts, as in polishing. Electron microscopy observations of Ti-6Al-4V surface with a spherical asperity structure-realized via additive manufacturing-during successive polishing stages suggest that asperity-abrasive contacts exhibit viscous behavior, where the asperity material flows in the form of thin (1-10 µm) fluid-like layers. Subsequent bridging of these layers among neighboring asperities results in progressive surface smoothening. Using analytical asperity-abrasive contact temperature modeling and microstructural characterization, we show that the sliding contacts encounter flash temperatures of the order of 700-900 K which is in the range of the dynamic recrystallization temperature of the material considered, thus supporting the experimental observations. Besides providing a new perspective on the long-held mechanism of polishing, our observations provide a novel approach based on graph theory to quantitatively characterize the evolution of surface morphology. Results suggest that the graph representation offers a more efficient measure to characterize the surface morphology emerging at various stages of polishing. The research findings and observations are of broad relevance to the understanding of plastic flow behavior of sliding contacts ubiquitous in materials processing, tribology, and natural geological processes as well as present unique opportunities to tailor the microstructures by controlling the thermomechanics of the asperity-abrasive contacts.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA