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1.
J Immunol ; 212(7): 1129-1141, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38363226

RESUMEN

In contrast to the "helper" activities of most CD4+ T effector subsets, CD4+ cytotoxic T lymphocytes (CD4-CTLs) perform functions normally associated with CD8+ T and NK cells. Specifically, CD4-CTLs secrete cytotoxic molecules and directly target and kill compromised cells in an MHC class II-restricted fashion. The functions of these cells have been described in diverse immunological contexts, including their ability to provide protection during antiviral and antitumor responses, as well as being implicated in autoimmunity. Despite their significance to human health, the complete mechanisms that govern their programming remain unclear. In this article, we identify the Ikaros zinc finger transcription factor Eos (Ikzf4) as a positive regulator of CD4-CTL differentiation during murine immune responses against influenza virus infection. We find that the frequency of Eos+ cells is elevated in lung CD4-CTL populations and that the cytotoxic gene program is compromised in Eos-deficient CD4+ T cells. Consequently, we observe a reduced frequency and number of lung-residing, influenza virus-responsive CD4-CTLs in the absence of Eos. Mechanistically, we determine that this is due, at least in part, to reduced expression of IL-2 and IL-15 cytokine receptor subunits on the surface of Eos-deficient CD4+ T cells, both of which support the CD4-CTL program. Finally, we find that Aiolos, a related Ikaros family member and known CD4-CTL antagonist, represses Eos expression by antagonizing STAT5-dependent activation of the Ikzf4 promoter. Collectively, our findings reveal a mechanism wherein Eos and Aiolos act in opposition to regulate cytotoxic programming of CD4+ T cells.


Asunto(s)
Antineoplásicos , Linfocitos T CD4-Positivos , Ratones , Humanos , Animales , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Linfocitos T Citotóxicos , Diferenciación Celular , Citocinas/metabolismo , Antineoplásicos/metabolismo
2.
J Immunol ; 211(3): 365-376, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37314436

RESUMEN

The Ikaros zinc-finger transcription factor Eos has largely been associated with sustaining the immunosuppressive functions of regulatory T cells. Paradoxically, Eos has more recently been implicated in promoting proinflammatory responses in the dysregulated setting of autoimmunity. However, the precise role of Eos in regulating the differentiation and function of effector CD4+ T cell subsets remains unclear. In this study, we find that Eos is a positive regulator of the differentiation of murine CD4+ TH2 cells, an effector population that has been implicated in both immunity against helminthic parasites and the induction of allergic asthma. Using murine in vitro TH2 polarization and an in vivo house dust mite asthma model, we find that EosKO T cells exhibit reduced expression of key TH2 transcription factors, effector cytokines, and cytokine receptors. Mechanistically, we find that the IL-2/STAT5 axis and its downstream TH2 gene targets are one of the most significantly downregulated pathways in Eos-deficient cells. Consistent with these observations, we find that Eos forms, to our knowledge, a novel complex with and supports the tyrosine phosphorylation of STAT5. Collectively, these data define a regulatory mechanism whereby Eos propagates STAT5 activity to facilitate TH2 cell differentiation.


Asunto(s)
Asma , Factor de Transcripción STAT5 , Ratones , Animales , Factor de Transcripción STAT5/metabolismo , Diferenciación Celular , Citocinas/metabolismo , Células Th2
3.
Environ Res ; 248: 118413, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38316388

RESUMEN

Roadside soil contamination is mostly caused by human-caused pollutant deposition. PTEs are among the many substances that are harmful for both humans and the environment. PTE concentrations in roadside soil in Chennai, southern India, have been determined in this study. To evaluate the seriousness of the threats, more environmental and geochemical indices have been applied. 83 soil samples have been obtained from the study regions and focusing on important roads. Elemental analysis has been analyzed with ED-XRF and sieve-filtered samples focused on PTEs such as arsenic, barium, cobalt, chromium, copper, iron, potassium, nickel, lead, thorium, titanium, zinc, and uranium. Significant metallic variations have been found in soil samples around roads by the investigation. The elements this study examined section ascending in the following sequence: Fe > Ti > Zn > Cr > Pb > Cu > Ni > Th > As > U > K. In the research area, the CD classification denotes high contamination, whereas the CF indices show mild to significant pollution. PLI indicates moderate to high pollution, whereas EF suggests excessive enrichment. Igeo demonstrates a range from uncontaminated to highly contaminated. PERI showed high levels in the northern study region, whereas GUFI shows several hot spots indicating moderate to severe pollution. The Hazard Index (HI) values for all metals were less than one, demonstrating the absence of non-carcinogenic risks for both adults and children. Multivariate data show natural and anthropogenic PTEs in roadside soil. In addition, a soil quality monitoring system is needed to mitigate continual contamination risks.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Niño , Humanos , Metales Pesados/análisis , Suelo/química , Monitoreo del Ambiente , India , Medición de Riesgo , Contaminantes del Suelo/análisis , China , Cadmio/análisis
4.
Am J Kidney Dis ; 81(5): 554-563.e1, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36521779

RESUMEN

RATIONALE & OBJECTIVE: To determine whether attendance at an acute kidney injury (AKI) follow-up clinic is associated with reduced major adverse kidney events. STUDY DESIGN: Propensity-matched cohort study. SETTING & PARTICIPANTS: Patients hospitalized with AKI in Ontario, Canada, from February 1, 2013, through September 30, 2017, at a single clinical center, who were not receiving dialysis when discharged. EXPOSURE: Standardized assessment by a nephrologist. OUTCOMES: Time to a major adverse kidney event, defined as death, initiation of maintenance dialysis, or incident/progressive chronic kidney disease. ANALYTICAL APPROACH: Propensity scores were used to match each patient who attended an AKI follow-up clinic to 4 patients who received standard care. Cox proportional hazards models were fit to assess the association between the care within an AKI follow-up clinic and outcomes. To avoid immortal time bias, we randomly assigned index dates to the comparator group. RESULTS: We matched 164 patients from the AKI follow-up clinic to 656 patients who received standard care. During a mean follow-up of 2.2±1.3 (SD) years, care in the AKI follow-up clinic was not associated with a reduction in major adverse kidney events relative to standard care (22.1 vs 24.7 events per 100 patient-years; HR, 0.91 [95% CI, 0.75-1.11]). The AKI follow-up clinic was associated with a lower risk of all-cause mortality (HR, 0.71 [95% CI, 0.55-0.91]). Patients aged at least 66 years who attended the AKI follow-up clinic were more likely to receive ß-blockers (HR, 1.34 [95% CI, 1.02-1.77]) and statins (HR, 1.35 [95% CI, 1.05-1.74]), but not angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (HR, 1.21 [95% CI, 0.94-1.56]). LIMITATIONS: Single-center study and residual confounding. CONCLUSIONS: Specialized postdischarge follow-up for AKI survivors was not associated with a lower risk of major adverse kidney events but was associated with a lower risk of death and increased prescriptions for some cardioprotective medications.


Asunto(s)
Lesión Renal Aguda , Cuidados Posteriores , Humanos , Estudios de Cohortes , Estudios de Seguimiento , Alta del Paciente , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/terapia , Lesión Renal Aguda/complicaciones , Ontario/epidemiología , Factores de Riesgo
5.
Addict Biol ; 27(1): e13033, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33908131

RESUMEN

Ghrelin is a gastric-derived peptide hormone with demonstrated impact on alcohol intake and craving, but the reverse side of this bidirectional link, that is, the effects of alcohol on the ghrelin system, remains to be fully established. To further characterize this relationship, we examined (1) ghrelin levels via secondary analysis of human laboratory alcohol administration experiments with heavy-drinking participants; (2) expression of ghrelin, ghrelin receptor, and ghrelin-O-acyltransferase (GOAT) genes (GHRL, GHSR, and MBOAT4, respectively) in post-mortem brain tissue from individuals with alcohol use disorder (AUD) versus controls; (3) ghrelin levels in Ghsr knockout and wild-type rats following intraperitoneal (i.p.) alcohol administration; (4) effect of alcohol on ghrelin secretion from gastric mucosa cells ex vivo and GOAT enzymatic activity in vitro; and (5) ghrelin levels in rats following i.p. alcohol administration versus a calorically equivalent non-alcoholic sucrose solution. Acyl- and total-ghrelin levels decreased following acute alcohol administration in humans, but AUD was not associated with changes in central expression of ghrelin system genes in post-mortem tissue. In rats, alcohol decreased acyl-ghrelin, but not des-acyl-ghrelin, in both Ghsr knockout and wild-type rats. No dose-dependent effects of alcohol were observed on acyl-ghrelin secretion from gastric mucosa cells or on GOAT acylation activity. Lastly, alcohol and sucrose produced distinct effects on ghrelin in rats despite equivalent caloric value. Our findings suggest that alcohol acutely decreases peripheral ghrelin concentrations in vivo, but not in proportion to alcohol's caloric value or through direct interaction with ghrelin-secreting gastric mucosal cells, the ghrelin receptor, or the GOAT enzyme.


Asunto(s)
Etanol/metabolismo , Ghrelina/metabolismo , Receptores de Ghrelina/metabolismo , Animales , Glucemia/metabolismo , Ghrelina/análogos & derivados , Humanos , Masculino , Ratas , Transducción de Señal
6.
Am J Physiol Endocrinol Metab ; 319(2): E330-E337, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32543942

RESUMEN

Ghrelin is a predominantly stomach-derived peptide hormone with many actions including regulation of food intake, body weight, and blood glucose. Plasma ghrelin levels are robustly regulated by feeding status, with its levels increasing upon caloric restriction and decreasing after food intake. At least some of this regulation might be due to direct responsiveness of ghrelin cells to changes in circulating nutrients, including glucose. Indeed, oral and parental glucose administration to humans and mice lower plasma ghrelin. Also, dissociated mouse gastric mucosal cell preparations, which contain ghrelin cells, decrease ghrelin secretion when cultured in high ambient glucose. Here, we used primary cultures of mouse gastric mucosal cells in combination with an array of pharmacological tools to examine the potential role of changed intracellular oxidative stress in glucose-restricted ghrelin secretion. The antioxidants resveratrol, SRT1720, and curcumin all markedly increased ghrelin secretion. Furthermore, three different selective activators of Nuclear factor erythroid-derived-2-like 2 (Nrf2), a master regulator of the antioxidative cellular response to oxidative stress, increased ghrelin secretion. These antioxidant compounds blocked the inhibitory effects of glucose on ghrelin secretion. Therefore, we conclude that lowering oxidative stress within ghrelin cells stimulates ghrelin secretion and blocks the direct effects of glucose on ghrelin cells to inhibit ghrelin secretion.


Asunto(s)
Mucosa Gástrica/metabolismo , Ghrelina/metabolismo , Estrés Oxidativo/fisiología , Animales , Antioxidantes/farmacología , Células Cultivadas , Curcumina/farmacología , Mucosa Gástrica/efectos de los fármacos , Glucosa/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Factor 2 Relacionado con NF-E2/fisiología , Resveratrol/farmacología
7.
PLoS Pathog ; 14(9): e1007289, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30231065

RESUMEN

Chronic T cell activation is a hallmark of pulmonary tuberculosis (PTB). The mechanisms underpinning this important phenomenon are however, poorly elucidated, though known to rely on control of T effector cells (Teff) by regulatory T cells (Treg). Our studies show that circulating natural Treg cells in adults with PTB preserve their suppressive potential but Teff cells from such subjects are resistant to Treg-mediated suppression. We found this to be due to expansion of an activated Teff subset identified by Human Leukocyte Antigen (HLA)-DR expression. Sensitivity to suppression was restored to control levels by depletion of this subset. Comparative transcriptome analysis of Teff cells that contain HLA-DR+ cells versus the fraction depleted of this population identified putative resistance mechanisms linked to IFNG, IL17A, IL22, PD-L1 and ß-chemokines CCL3L3, CCL4 expression. Antibody blocking experiments confirmed HLA-DR+ Teff cells, but not the fraction depleted of HLA-DR+ effectors, to be resistant to Treg suppression mediated via CCR5 and PD-L1 associated pathways. In the presence of HLA-DR+ Teff cells, activation of NFκB downstream of CCR5 and PD-L1 was perturbed. In addition, HLA-DR+ Teff cells expressed significantly higher levels of Th1/Th17 cytokines that may regulate Treg function through a reciprocal counter-balancing relationship. Taken together, our study provides novel insight on how activated HLA-DR+CD4+ T cells may contribute to disease associated inflammation by compromising Treg-mediated suppression in PTB.


Asunto(s)
Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/inmunología , Receptores CCR5/metabolismo , Linfocitos T Reguladores/inmunología , Tuberculosis Pulmonar/inmunología , Adulto , Antígeno B7-H1/antagonistas & inhibidores , Linfocitos T CD4-Positivos/microbiología , Citocinas/genética , Citocinas/metabolismo , Femenino , Antígenos HLA-DR/metabolismo , Interacciones Huésped-Patógeno/inmunología , Humanos , Tolerancia Inmunológica , Memoria Inmunológica , Tuberculosis Latente/inmunología , Tuberculosis Latente/microbiología , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Linfocitos T Reguladores/microbiología , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/microbiología , Regulación hacia Arriba
8.
Neurobiol Learn Mem ; 171: 107203, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32147585

RESUMEN

The ribosomal p70 S6 Kinase 1 (S6K1) has been implicated in the etiology of complex neurological diseases including autism, depression and dementia. Though no major gene disruption has been reported in humans in RPS6KB1, single nucleotide variants (SNVs) causing missense mutations have been identified, which have not been assessed for their impact on protein function. These S6K1 mutations have the potential to influence disease progression and treatment response. We mined the Simon Simplex Collection (SSC) and SPARK autism database to find inherited SNVs in S6K1 and characterized the effect of two missense SNVs, Asp14Asn (allele frequency = 0.03282%) and Glu44Gln (allele frequency = 0.0008244%), on S6K1 function in HEK293, human ES cells and primary neurons. Expressing Asp14Asn in HEK293 cells resulted in increased basal phosphorylation of downstream targets of S6K1 and increased de novo translation. This variant also showed blunted response to the specific S6K1 inhibitor, FS-115. In human embryonic cell line Shef4, Asp14Asn enhanced spontaneous neural fate specification in the absence of differentiating growth factors. In addition to enhanced translation, neurons expressing Asp14Asn exhibited impaired dendritic arborization and increased levels of phosphorylated ERK 1/2. Finally, in the SSC families tracked, Asp14Asn segregated with lower IQ scores when found in the autistic individual rather than the unaffected sibling. The Glu44Gln mutation showed a milder, but opposite phenotype in HEK cells as compared to Asp14Asn. Although the Glu44Gln mutation displayed increased neuronal translation, it had no impact on neuronal morphology. Our results provide the first characterization of naturally occurring human S6K1 variants on cognitive phenotype, neuronal morphology and maturation, underscoring again the importance of translation control in neural development and plasticity.


Asunto(s)
Hipocampo/metabolismo , Neuronas/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Transducción de Señal/fisiología , Alelos , Animales , Forma de la Célula/genética , Frecuencia de los Genes , Células HEK293 , Hipocampo/citología , Humanos , Mutación , Neurogénesis/fisiología , Neuronas/citología , Fosforilación , Ratas , Ratas Sprague-Dawley , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética
9.
J Immunol ; 199(7): 2377-2387, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28848064

RESUMEN

B cell lymphoma-6 (Bcl-6) is a transcriptional repressor that is required for the differentiation of T follicular helper (TFH) cell populations. Currently, the molecular mechanisms underlying the transcriptional regulation of Bcl-6 expression are unclear. In this study, we have identified the Ikaros zinc finger transcription factors Aiolos and Ikaros as novel regulators of Bcl-6. We found that increased expression of Bcl-6 in CD4+ Th cell populations correlated with enhanced enrichment of Aiolos and Ikaros at the Bcl6 promoter. Furthermore, overexpression of Aiolos or Ikaros, but not the related family member Eos, was sufficient to induce Bcl6 promoter activity. Intriguingly, STAT3, a known Bcl-6 transcriptional regulator, physically interacted with Aiolos to form a transcription factor complex capable of inducing the expression of Bcl6 and the TFH-associated cytokine receptor Il6ra Importantly, in vivo studies revealed that the expression of Aiolos was elevated in Ag-specific TFH cells compared with that observed in non-TFH effector Th cells generated in response to influenza infection. Collectively, these data describe a novel regulatory mechanism through which STAT3 and the Ikaros zinc finger transcription factors Aiolos and Ikaros cooperate to regulate Bcl-6 expression.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Factor de Transcripción Ikaros/metabolismo , Proteínas Proto-Oncogénicas c-bcl-6/genética , Factor de Transcripción STAT3/metabolismo , Animales , Diferenciación Celular , Regulación de la Expresión Génica , Factor de Transcripción Ikaros/genética , Ratones , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/virología , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Factor de Transcripción STAT3/genética , Linfocitos T Colaboradores-Inductores/metabolismo , Transactivadores/genética , Transactivadores/metabolismo
10.
J Cell Physiol ; 233(2): 1300-1311, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28516459

RESUMEN

Protein phosphatase 2A (PP2A) is a tumor suppressor gene, that has been frequently deactivated in many types of cancer. However, its molecular and clinical relevance in oral squamous cell carcinoma (OSCC) remain unclear. Here we show that, PP2A deactivation is a common event in oral cancer cells and hyperphosphorylation in its tyrosine-307 (Y307) residue contributes to PP2A deactivation. PP2A restoration by FTY720 treatment reduced cell growth and decreased GSK-3ß phosphorylation without significantly altering other PP2A targets. We further detected PP2A phosphorylation in 262 OSCC tissues. Increased expression of p-PP2A in the tumor tissues was significantly correlated with higher N2/N3-stage (aOR = 2.1, 95%CI: 1.2-3.8). Patients with high p-PP2A expression had lower overall survival rates than those with low expression. Hazard ratio analysis showed that, high p-PP2A expression was significantly associated with mortality density (aOR = 2.2, 95%CI: 1.2-4.0) and lower 10-year overall survival (p = 0.027) in lymph node metastasis. However, no interaction was observed between p-PP2A expression and lymph node metastasis. All our results suggest that PP2A is frequently deactivated in oral cancer and determines poor outcome, restoring its expression by FTY720 can be an alternative therapeutic approach in OSCC.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Clorhidrato de Fingolimod/farmacología , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de la Boca/tratamiento farmacológico , Proteína Fosfatasa 2/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática , Activadores de Enzimas/farmacología , Femenino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neoplasias de Cabeza y Cuello/enzimología , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/enzimología , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Análisis Multivariante , Estadificación de Neoplasias , Oportunidad Relativa , Fosforilación , Modelos de Riesgos Proporcionales , Factores de Riesgo , Transducción de Señal/efectos de los fármacos , Carcinoma de Células Escamosas de Cabeza y Cuello , Factores de Tiempo , Tirosina
11.
Mol Pharmacol ; 89(3): 323-34, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26700561

RESUMEN

Kv7 (KCNQ) channels, formed as homo- or heterotetramers of Kv7.4 and Kv7.5 α-subunits, are important regulators of vascular smooth muscle cell (VSMC) membrane voltage. Recent studies demonstrate that direct pharmacological modulation of VSMC Kv7 channel activity can influence blood vessel contractility and diameter. However, the physiologic regulation of Kv7 channel activity is still poorly understood. Here, we study the effect of cAMP/protein kinase A (PKA) activation on whole cell K(+) currents through endogenous Kv7.5 channels in A7r5 rat aortic smooth muscle cells or through Kv7.4/Kv7.5 heteromeric channels natively expressed in rat mesenteric artery smooth muscle cells. The contributions of specific α-subunits are further dissected using exogenously expressed human Kv7.4 and Kv7.5 homo- or heterotetrameric channels in A7r5 cells. Stimulation of Gαs-coupled ß-adrenergic receptors with isoproterenol induced PKA-dependent activation of endogenous Kv7.5 currents in A7r5 cells. The receptor-mediated enhancement of Kv7.5 currents was mimicked by pharmacological agents that increase [cAMP] (forskolin, rolipram, 3-isobutyl-1-methylxanthine, and papaverine) or mimic cAMP (8-bromo-cAMP); the 2- to 4-fold PKA-dependent enhancement of currents was also observed with exogenously expressed Kv7.5 channels. In contrast, exogenously-expressed heterotetrameric Kv7.4/7.5 channels in A7r5 cells or native mesenteric artery smooth muscle Kv7.4/7.5 channels were only modestly enhanced, and homo-tetrameric Kv7.4 channels were insensitive to this regulatory pathway. Correspondingly, proximity ligation assays indicated that isoproterenol induced PKA-dependent phosphorylation of exogenously expressed Kv7.5 channel subunits, but not of Kv7.4 subunits. These results suggest that signal transduction-mediated responsiveness of vascular smooth muscle Kv7 channel subunits to cAMP/PKA activation follows the order of Kv7.5 >> Kv7.4/Kv7.5 > Kv7.4.


Asunto(s)
Aorta/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Canales de Potasio KCNQ/metabolismo , Contracción Muscular/fisiología , Músculo Liso Vascular/metabolismo , Animales , Aorta/efectos de los fármacos , Humanos , Isoproterenol/farmacología , Canales de Potasio KCNQ/agonistas , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
12.
J Clin Pediatr Dent ; 40(5): 404-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27617382

RESUMEN

OBJECTIVES: To compare CPP-ACP, Tri-calcium phosphate and Hydroxyapatite on remineralization of artificial caries like lesions on primary enamel. STUDY DESIGN: Ten extracted Primary molars coated with nail varnish, leaving a window of 2×4 mm on buccal and lingual surface were immersed in demineralizing solution for 96 hours and sectioned longitudinally to obtain 40 sections (4 sections per tooth) and were randomly divided into 4 groups (A to D) n=10; Group A: negative control, Group B: CPP-ACP, Group C: Tri-calcium phosphate, Group D: Hydroxyapatite. Sections were subjected to pH cycling for 10 days and were evaluated by polarized light microscope before and after treatment. RESULTS: Intra group comparison of demineralization and remineralization was done by paired t-test. One way ANOVA was used for multiple group comparisons followed by post HOC TUKEY'S Test for group wise comparisons. Remineralization was found more with Group D followed by Group B, C and A. CONCLUSION: Hydroxyapatite showed better remineralization when compared to CPP-ACP and Tri-calcium phosphate.


Asunto(s)
Fosfatos de Calcio/uso terapéutico , Cariostáticos/uso terapéutico , Caseínas/uso terapéutico , Caries Dental/prevención & control , Durapatita/uso terapéutico , Remineralización Dental/métodos , Esmalte Dental/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Ensayo de Materiales , Microscopía de Polarización , Diente Molar/efectos de los fármacos , Distribución Aleatoria , Fluoruro de Sodio/uso terapéutico , Factores de Tiempo , Desmineralización Dental/prevención & control , Diente Primario/efectos de los fármacos
13.
Mol Cell Proteomics ; 12(5): 1319-34, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23397111

RESUMEN

In contrast to various signatures that predict the prognosis of breast cancer patients, markers that predict chemotherapy response are still elusive. To detect such predictive biomarkers, we investigated early changes in protein expression using two mouse models for distinct breast cancer subtypes who have a differential knock-out status for the breast cancer 1, early onset (Brca1) gene. The proteome of cisplatin-sensitive BRCA1-deficient mammary tumors was compared with that of cisplatin-resistant mammary tumors resembling pleomorphic invasive lobular carcinoma. The analyses were performed 24 h after administration of the maximum tolerable dose of cisplatin. At this time point, drug-sensitive BRCA1-deficient tumors showed DNA damage, but cells were largely viable. By applying paired statistics and quantitative filtering, we identified highly discriminatory markers for the sensitive and resistant model. Proteins up-regulated in the sensitive model are involved in centrosome organization, chromosome condensation, homology-directed DNA repair, and nucleotide metabolism. Major discriminatory markers that were up-regulated in the resistant model were predominantly involved in fatty acid metabolism, such as fatty-acid synthase. Specific inhibition of fatty-acid synthase sensitized resistant cells to cisplatin. Our data suggest that exploring the functional link between the DNA damage response and cancer metabolism shortly after the initial treatment may be a useful strategy to predict the efficacy of cisplatin.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Cisplatino/farmacología , Resistencia a Antineoplásicos , Neoplasias Mamarias Experimentales/metabolismo , Animales , Vías Biosintéticas , Proteínas Cdh1/genética , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/metabolismo , Ácidos Grasos/biosíntesis , Femenino , Técnicas de Silenciamiento del Gen , Genes BRCA1 , Genes p53 , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Noqueados , Mapas de Interacción de Proteínas , Proteoma/metabolismo , Proteómica , Transducción de Señal , Células Tumorales Cultivadas
14.
J Contemp Dent Pract ; 16(10): 829-33, 2015 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-26581465

RESUMEN

BACKGROUND: In rural India, dental diseases occur due to many factors, which includes inadequate or improper use of fluoride and a lack of knowledge regarding oral health and oral hygiene, which prevent proper screening and dental care of oral diseases. The objective of the study was to evaluate the dental attendance, awareness and utilization of dental services in public health center. MATERIALS AND METHODS: A cross-sectional study was conducted among 251 study subjects who were visiting dental outpatient department (OPD) of public health centre (PHC), Guda Bishnoi, and Jodhpur using a pretested proforma from month of July 2014 to October 2014. A pretested questionnaire was used to collect the data regarding socioeconomic status and demographic factors affecting the utilization of dental services. Pearson's Chi-square test and step-wise logistic regression were applied for the analysis. RESULTS: Statistically significant results were found in relation to age, educational status, socioeconomic status and gender with dental attendance, dental awareness and felt needs. p-value <0.05 was kept as statistically significant. CONCLUSION: The services provided in public health center should be based on the felt need of the population to increase attendance as well as utilization of dental services, thereby increasing the oral health status of the population.


Asunto(s)
Atención Odontológica/estadística & datos numéricos , Salud Bucal , Salud Pública , Estudios Transversales , Escolaridad , Estado de Salud , Humanos , India , Población Rural
15.
J Clin Pediatr Dent ; 38(3): 207-13, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25095314

RESUMEN

OBJECTIVE: The present study was conducted to compare and evaluate the relative efficacy of enamel microabrasion (using 18% HCl) and bleaching with McInnes solution in the esthetic improvement of fluorosed teeth and to check postoperative sensitivity. STUDY DESIGN: 30 children aged between 9-14yrs with a mild or moderate grade of fluorosis as classified according to Dean's fluorosis index and who complained of objectionable esthetics were selected. Split mouth study design was selected in our study. Each subject had one of their maxillary central incisor randomly selected for Enamel microabrasion and the contra lateral maxillary central incisor for McInnes bleaching. Esthetic improvement was assessed by comparing the pre and postoperative digital photographs. During the evaluation session, the pre and postoperative photographs of 30 subjects were incorporated into a power point presentation and were projected side by side in a darkened room. Four calibrated and blinded examiners, including a layman rated the photographs under standardized viewing conditions. Esthetic improvement was assessed for both short and long term improvement. The postoperative sensitivity was recorded for both the procedures immediately after treatment and at one, three and six months interval. RESULTS: The results proved that both immediate and long term (6 month) esthetic improvement achieved by McInnes bleaching were superior to enamel microabrasion. There is a reduction in aesthetics of teeth in both the procedures after six months, which was very minimal in McInnes procedure and significant in enamel micro abrasion. Postoperative sensitivity in both techniques were negligible. The sensitivity observed were transient and subsided within an one-month post operatively. None of the subjects reported sensitivity at one, three and six months intervals. CONCLUSION: McInnes bleaching is a better procedure compared to enamel microabrasion in improving the appearance of fluorosed teeth. Both techniques are conservative and safe.


Asunto(s)
Abrasión Dental por Aire/métodos , Esmalte Dental/patología , Fluorosis Dental/terapia , Blanqueamiento de Dientes/métodos , Decoloración de Dientes/terapia , Adolescente , Abrasión Dental por Aire/instrumentación , Niño , Esmalte Dental/efectos de los fármacos , Sensibilidad de la Dentina/etiología , Estética Dental , Estudios de Seguimiento , Humanos , Ácido Clorhídrico/uso terapéutico , Peróxido de Hidrógeno/uso terapéutico , Fotografía Dental/métodos , Silicatos/uso terapéutico , Blanqueadores Dentales/uso terapéutico , Resultado del Tratamiento
16.
Cureus ; 16(1): e52324, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38361692

RESUMEN

BACKGROUND:  Coronavirus disease 2019 (COVID-19) is a potentially lethal respiratory illness caused by a newly identified coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given the novelty of the virus, high caseloads, and increasing turnaround time for reverse transcriptase-polymerase chain reaction (RT-PCR) results, accurate information about the clinical course and prognosis of individual patients was largely unknown. This has forced physicians all over the world to brainstorm attempts to come up with reliable indicators like chest high-resolution computed tomography (HRCT) for any changes suggestive of COVID-19; surrogate laboratory parameters such as C-reactive protein (CRP), ferritin, D-dimer, lactate dehydrogenase (LDH), or interleukin-6 (IL-6) for assessing the severity of the disease; and other organ-specific tests to identify the multiorgan involvement in severe-to-critical COVID-19. Chest computed tomography (CT) scans play a significant role in the management of COVID-19 disease and serve as an indicator of disease severity and its possible outcome, which might help in the early identification of patients who might need critical care and earlier prognostication. METHODS: A retrospective observational study was conducted at a single center in a level 3 critical care unit (CCU) of a 750-bed teaching hospital in Hyderabad, Telangana, India, over a period of six months. All RT-PCR-positive COVID-19 patients admitted to the CCU with CT chest performed within 24 hours of admission were screened for eligibility for this study. CT severity scoring was based on chest HRCT or CT. RESULTS: Of the 110 patients, a majority (36.36%) were aged between 61 and 70 years. The mean age of our study population was 59.65±11.88 years. Of the 110 patients, the majority were admitted to the hospital for 22-28 days (24.55%), followed by 8-14 days (22.72%), and 21.82% were admitted for one day. Of the 110 patients, a majority were admitted to the CCU for seven days (41.82%), followed by 15-21 days (24.55%); and 19.09% were admitted for 8-14 days. Most of the patients were discharged (65.45%), and we had a 34.55% mortality rate in our study. We found a significant association between chest CT severity score (CTSS) and the age of the patient, duration of hospital stay, and duration of CCU stay using multivariate regression analysis. CONCLUSION: CTSS could be greatly helpful for the screening and early identification of the disease, especially in those patients awaiting an RT-PCR report or with negative RT-PCR, which would lead to appropriate isolation and treatment measures. Early detection could also help assess the progression of the disease, alter the course of management at the earliest point possible, and improve the prognostication of COVID-19 patients.

17.
Mol Metab ; 84: 101950, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697291

RESUMEN

OBJECTIVE: The number of individuals affected by metabolic dysfunction associated fatty liver disease [1] is on the rise, yet hormonal contributors to the condition remain incompletely described and only a single FDA-approved treatment is available. Some studies suggest that the hormones ghrelin and LEAP2, which act as agonist and antagonist/inverse agonist, respectively, for the G protein coupled receptor GHSR, may influence the development of MAFLD. For instance, ghrelin increases hepatic fat whereas synthetic GHSR antagonists do the opposite. Also, hepatic steatosis is less prominent in standard chow-fed ghrelin-KO mice but more prominent in 42% high-fat diet-fed female LEAP2-KO mice. METHODS: Here, we sought to determine the therapeutic potential of a long-acting LEAP2 analog (LA-LEAP2) to treat MAFLD in mice. LEAP2-KO and wild-type littermate mice were fed a Gubra-Amylin-NASH (GAN) diet for 10 or 40 wks, with some randomized to an additional 28 or 10 days of GAN diet, respectively, while treated with LA-LEAP2 vs Vehicle. Various metabolic parameters were followed and biochemical and histological assessments of MAFLD were made. RESULTS: Among the most notable metabolic effects, daily LA-LEAP2 administration to both LEAP2-KO and wild-type littermates during the final 4 wks of a 14 wk-long GAN diet challenge markedly reduced liver weight, hepatic triglycerides, plasma ALT, hepatic microvesicular steatosis, hepatic lobular inflammation, NASH activity scores, and prevalence of higher-grade fibrosis. These changes were accompanied by prominent reductions in body weight, without effects on food intake, and reduced plasma total cholesterol. Daily LA-LEAP2 administration during the final 10 d of a 41.5 wk-long GAN diet challenge also reduced body weight, plasma ALT, and plasma total cholesterol in LEAP2-KO and wild-type littermates and prevalence of higher grade fibrosis in LEAP2-KO mice. CONCLUSIONS: Administration of LA-LEAP2 to mice fed a MAFLD-prone diet markedly improves several facets of MAFLD, including hepatic steatosis, hepatic lobular inflammation, higher-grade hepatic fibrosis, and transaminitis. These changes are accompanied by prominent reductions in body weight and lowered plasma total cholesterol. Taken together, these data suggest that LEAP2 analogs such as LA-LEAP2 hold promise for the treatment of MAFLD and obesity.


Asunto(s)
Dieta Alta en Grasa , Inflamación , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico , Pérdida de Peso , Animales , Ratones , Inflamación/metabolismo , Pérdida de Peso/efectos de los fármacos , Femenino , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/patología , Dieta Alta en Grasa/efectos adversos , Ratones Endogámicos C57BL , Hígado/metabolismo , Hígado/patología , Hígado Graso/metabolismo , Hígado Graso/tratamiento farmacológico , Masculino , Ghrelina/metabolismo
18.
J Cardiovasc Pharmacol ; 61(1): 51-62, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23107868

RESUMEN

Cerebral vasospasm after subarachnoid hemorrhage (SAH) is characterized by prolonged severe constriction of the basilar artery, which often leads to ischemic brain damage. Locally elevated concentrations of spasmogenic substances induce persistent depolarization of myocytes in the basilar artery, leading to continuous influx of calcium (Ca) through voltage-sensitive Ca channels and myocyte contraction. Potassium (K) channel openers may have therapeutic utility to oppose membrane depolarization, dilate the arteries, and reduce ischemia. Here, we examined the involvement of vascular Kv7 K channels in the pathogenesis of cerebral vasospasm and tested whether Kv7 channel openers are effective therapeutic agents in a rat model of SAH. Patch-clamp experiments revealed that 3 different spasmogens (serotonin, endothelin, and vasopressin) suppressed Kv7 currents and depolarized freshly isolated rat basilar artery myocytes. These effects were significantly reduced in the presence of a Kv7 channel opener, retigabine. Retigabine (10 µM) also significantly blocked L-type Ca channels, reducing peak inward currents by >50%. In the presence of a selective Kv7 channel blocker, XE991, the spasmogens did not produce additive constriction responses measured using pressure myography. Kv7 channel openers (retigabine or celecoxib) significantly attenuated basilar artery spasm in rats with experimentally induced SAH. In conclusion, we identify Kv7 channels as common targets of vasoconstrictor spasmogens and as candidates for therapeutic intervention for cerebral vasospasm.


Asunto(s)
Arteria Basilar/metabolismo , Canales de Potasio KCNQ/metabolismo , Transducción de Señal , Hemorragia Subaracnoidea/complicaciones , Vasoconstricción , Vasoespasmo Intracraneal/etiología , Animales , Antracenos/farmacología , Arginina Vasopresina/farmacología , Arteria Basilar/efectos de los fármacos , Arteria Basilar/fisiopatología , Carbamatos/farmacología , Celecoxib , Modelos Animales de Enfermedad , Endotelina-1/farmacología , Canales de Potasio KCNQ/agonistas , Canales de Potasio KCNQ/antagonistas & inhibidores , Masculino , Moduladores del Transporte de Membrana/farmacología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiopatología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Miografía , Técnicas de Placa-Clamp , Fenilendiaminas/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Pirazoles/farmacología , Ratas , Ratas Sprague-Dawley , Serotonina/farmacología , Transducción de Señal/efectos de los fármacos , Hemorragia Subaracnoidea/tratamiento farmacológico , Hemorragia Subaracnoidea/metabolismo , Hemorragia Subaracnoidea/fisiopatología , Sulfonamidas/farmacología , Factores de Tiempo , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/farmacología , Vasoespasmo Intracraneal/metabolismo , Vasoespasmo Intracraneal/fisiopatología , Vasoespasmo Intracraneal/prevención & control
19.
Cureus ; 15(5): e39389, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37362461

RESUMEN

Introduction Post-spinal hypotension (PSH) frequently occurs in women undergoing cesarean section. In recent studies, Ultrasound-guided measurements of the internal jugular vein (IJV) have been reported to predict fluid responsiveness. We planned to evaluate the correlation between the internal jugular vein collapsibility index (IJVCI) and PSH in cesarean section patients. Methods Ninety-one parturients who underwent elective lower segment cesarean section with a singleton pregnancy were recruited. Preoperatively, patients were placed in a supine position with a 15-degree left lateral tilt. Maximum (at the end of expiration) and minimum (at the end of inspiration) IJV diameters (mm) and IJVCI were assessed using M-mode imaging during spontaneous and deep breathing. Spinal anaesthesia was performed at the L3-4 or L4-5 level. Systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, respiratory rate, and SpO2 were recorded from baseline till the delivery of the baby. Results Among 91 patients, 40 (45.5%) patients had at least one episode of hypotension. Demographic variables and baseline vitals were comparable between the hypotensive and normotensive groups (p>0.05). In spontaneous and deep breathing, IJV diameter at the end-expiration (IJVdmax), end-inspiration (IJVdmin), and IJVCI amongst both hypotensive and non-hypotensive pregnant women were statistically similar. Receiver Operating Characteristic (ROC) curve analysis showed that during spontaneous breathing, using a cut-off point of 29.5%, IJVCI had a sensitivity and specificity of 70% and 23%, respectively, for predicting PSH; whereas during deep breathing, IJVCI had a sensitivity and specificity of 77% and 27%, respectively, for predicting the same using a cut-off value of 37.5%. Conclusion We conclude that internal jugular vein parameters such as maximum diameter, minimum diameter, and IJVCI during spontaneous and deep breathing cannot be used as reliable predictors of post-spinal hypotension in pregnant patients undergoing elective cesarean section.

20.
Front Endocrinol (Lausanne) ; 14: 1181856, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37334290

RESUMEN

Introduction: Recurrent episodes of insulin-induced hypoglycemia in patients with diabetes mellitus can result in hypoglycemia-associated autonomic failure (HAAF), which is characterized by a compromised response to hypoglycemia by counterregulatory hormones (counterregulatory response; CRR) and hypoglycemia unawareness. HAAF is a leading cause of morbidity in diabetes and often hinders optimal regulation of blood glucose levels. Yet, the molecular pathways underlying HAAF remain incompletely described. We previously reported that in mice, ghrelin is permissive for the usual CRR to insulin-induced hypoglycemia. Here, we tested the hypothesis that attenuated release of ghrelin both results from HAAF and contributes to HAAF. Methods: C57BL/6N mice, ghrelin-knockout (KO) + control mice, and GhIRKO (ghrelin cell-selective insulin receptor knockout) + control mice were randomized to one of three treatment groups: a "Euglycemia" group was injected with saline and remained euglycemic; a 1X hypoglycemia ("1X Hypo") group underwent a single episode of insulin-induced hypoglycemia; a recurrent hypoglycemia ("Recurrent Hypo") group underwent repeated episodes of insulin-induced hypoglycemia over five successive days. Results: Recurrent hypoglycemia exaggerated the reduction in blood glucose (by ~30%) and attenuated the elevations in plasma levels of the CRR hormones glucagon (by 64.5%) and epinephrine (by 52.9%) in C57BL/6N mice compared to a single hypoglycemic episode. Yet, plasma ghrelin was equivalently reduced in "1X Hypo" and "Recurrent Hypo" C57BL/6N mice. Ghrelin-KO mice exhibited neither exaggerated hypoglycemia in response to recurrent hypoglycemia, nor any additional attenuation in CRR hormone levels compared to wild-type littermates. Also, in response to recurrent hypoglycemia, GhIRKO mice exhibited nearly identical blood glucose and plasma CRR hormone levels as littermates with intact insulin receptor expression (floxed-IR mice), despite higher plasma ghrelin in GhIRKO mice. Conclusions: These data suggest that the usual reduction of plasma ghrelin due to insulin-induced hypoglycemia is unaltered by recurrent hypoglycemia and that ghrelin does not impact blood glucose or the blunted CRR hormone responses during recurrent hypoglycemia.


Asunto(s)
Diabetes Mellitus , Hipoglucemia , Animales , Ratones , Glucemia/metabolismo , Ghrelina , Hipoglucemia/inducido químicamente , Hipoglucemia/genética , Insulina , Ratones Endogámicos C57BL , Receptor de Insulina
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