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1.
Am Surg ; 89(12): 5570-5576, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36866816

RESUMEN

INTRODUCTION: Clinical hypocalcemia (CH) following total thyroidectomy (TT) is a potentially life-threatening condition if left untreated. This study aimed at evaluating the accuracy of parathyroid hormone (PTH) measured in the early morning of the first postoperative day (POD-1) in predicting CH, and determining the cutoff values of PTH that can predict the development of CH. METHODS: We performed a retrospective review of patients undergoing TT between February 2018 and July 2022. Serum PTH, calcium, and albumin levels were measured on morning (6-8 AM) of postoperative day one (POD-1), and serum calcium level was measured from POD-2 onwards. We performed ROC curve analysis to determine the accuracy of PTH in predicting postoperative CH, and cutoff values of PTH to predict CH. RESULTS: Ninety-one patients, 52 (57.1%) with benign and 39 (42.9%) with malignant goiter were included. The incidence of biochemical, and clinical hypocalcemia was 24.2% and 30.8%, respectively. In our study serum, PTH measured in the early morning of first postoperative day following TT was found to have good accuracy (AUC = .88) in predicting CH. A PTH value of ≥27.15 pg/mL was found to have a 96.4% sensitivity in ruling out CH, while a serum PTH value <10.65 pg/mL had a specificity of 95.2% in predicting CH. DISCUSSION: Patients with a serum PTH value of ≥27.15 pg/mL can be discharged without any supplements, those with PTH <10.65 pg/mL should be started on calcium and calcitriol supplements, while patients having PTH values between 10.65 and 27.15 pg/mL should be monitored for the development of signs and/or symptoms of hypocalcemia.


Asunto(s)
Hipocalcemia , Hormona Paratiroidea , Humanos , Hipocalcemia/diagnóstico , Hipocalcemia/etiología , Calcio , Tiroidectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Estudios Prospectivos
2.
Cell Rep ; 37(11): 110109, 2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34910907

RESUMEN

This study addresses the roles of nuclear receptor corepressor 2 (NCOR2) in prostate cancer (PC) progression in response to androgen deprivation therapy (ADT). Reduced NCOR2 expression significantly associates with shorter disease-free survival in patients with PC receiving adjuvant ADT. Utilizing the CWR22 xenograft model, we demonstrate that stably reduced NCOR2 expression accelerates disease recurrence following ADT, associates with gene expression patterns that include neuroendocrine features, and induces DNA hypermethylation. Stably reduced NCOR2 expression in isogenic LNCaP (androgen-sensitive) and LNCaP-C4-2 (androgen-independent) cells revealed that NCOR2 reduction phenocopies the impact of androgen treatment and induces global DNA hypermethylation patterns. NCOR2 genomic binding is greatest in LNCaP-C4-2 cells and most clearly associates with forkhead box (FOX) transcription factor FOXA1 binding. NCOR2 binding significantly associates with transcriptional regulation most when in active enhancer regions. These studies reveal robust roles for NCOR2 in regulating the PC transcriptome and epigenome and underscore recent mutational studies linking NCOR2 loss of function to PC disease progression.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Andrógenos/deficiencia , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Recurrencia Local de Neoplasia/patología , Co-Represor 2 de Receptor Nuclear/antagonistas & inhibidores , Neoplasias de la Próstata/patología , Animales , Apoptosis , Biomarcadores de Tumor/genética , Proliferación Celular , Humanos , Masculino , Ratones , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/metabolismo , Co-Represor 2 de Receptor Nuclear/genética , Co-Represor 2 de Receptor Nuclear/metabolismo , Pronóstico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
3.
J Circadian Rhythms ; 19: 8, 2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34221066

RESUMEN

BACKGROUND: To address a critical gap for application of cancer chronotherapy of when would be the best time(s) for treating an individual cancer patient, we conducted a pilot study to characterize diurnal variations of gene expression in oral mucosal tissue, which is vulnerable to damage from cancer therapies. METHODS: We conducted RNA-seq assay on individual oral mucosal samples collected from 11 healthy volunteers every 4 hours (6 time points). Using a cosine-based method, we estimated the individual and average values of peak-time and amplitude for each gene. Correlations between gene expression peak-times and age was examined, adjusting for individual's sleep timing. RESULTS: Among candidate gene pathways that are relevant to treatment response, 7 of 16 genes (PER3, CIART, TEF, PER1, PER2, CRY2, ARNTL) involved in circadian regulation and 1 of 118 genes (WEE1) involved in cell cycle regulation achieved p-value ≤ 0.1 and relative amplitude>0.1. The average peak times were approximately 10:15 for PER3, CIART and TEF, 10:45 for PER1, 13:00 for WEE1, PER2 and CRY2, and 19:30 for ARNTL. Ranges in peak times across individuals differed by gene (e.g., 8 hours for PER1; 16.7 hours for WEE1). Older people had later peak times for PER1 (r = 0.77, p = 0.03) and PER3 (r = 0.69, p-value = 0.06). CONCLUSION: In oral mucosa, expression of some genes relevant to treatment response displayed diurnal variation. These genes may be candidates for development of biomarkers for optimizing individual timing of cancer therapy using non-invasively collected oral mucosa.

4.
J Inorg Biochem ; 220: 111461, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33882424

RESUMEN

Lactoperoxidase (LPO) is a mammalian heme peroxidase which catalyzes the conversion of thiocyanate (SCN¯) and iodide (I-) by hydrogen peroxide (H2O2) into antimicrobial hypothiocyanite (OSCN¯) and hypoiodite (IO-). The prosthetic heme group is covalently attached to LPO through two ester linkages involving conserved glutamate and aspartate residues. On the proximal side, His351 is coordinated to heme iron while His 109 is located in the substrate binding site on the distal heme side. We report here the first structure of the ternary complex of LPO with iodide (I-) and H2O2 at 1.77 Å resolution. LPO was crystallized with ammonium iodide and the crystals were soaked in the reservoir solution containing H2O2. Structure determination showed the presence of an iodide ion and a H2O2 molecule in the substrate binding site. The iodide ion occupied the position which is stabilized by the interactions with heme moiety, His109, Arg255 and Glu258 while H2O2 was held between the heme iron and His109. The presence of I- in the distal heme cavity seems to screen the positive charge of Arg255 thus suppressing the proton transfer from H2O2 to His109. This prevents compound I formation and allows trapping of a stable enzyme-substrate (LPO-I--H2O2) ternary complex. This stable geometrical arrangement of H2O2 in the distal heme cavity of LPO is similar to that of H2O2 in the structure of the transient intermediate of the palm tree heme peroxidase. The biochemical studies showed that the catalytic activity of LPO decreased when the samples of LPO were preincubated with ammonium iodide.


Asunto(s)
Peróxido de Hidrógeno/metabolismo , Yoduros/metabolismo , Lactoperoxidasa/metabolismo , Animales , Sitios de Unión , Bovinos , Calostro/enzimología , Cristalografía por Rayos X , Peróxido de Hidrógeno/química , Yoduros/química , Lactoperoxidasa/química , Unión Proteica , Estructura Terciaria de Proteína
5.
J Biol Inorg Chem ; 26(1): 149-159, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33427997

RESUMEN

Lactoperoxidase, a heme-containing glycoprotein, catalyzes the oxidation of thiocyanate by hydrogen peroxide into hypothiocyanite which acts as an antibacterial agent. The prosthetic heme moiety is attached to the protein through two ester linkages via Glu258 and Asp108. In lactoperoxidase, the substrate-binding site is formed on the distal heme side. To study the effect of physiologically important potassium ion on the structure and function of lactoperoxidase, the fresh protein samples were isolated from yak (Bos grunniens) colostrum and purified to homogeneity. The biochemical studies with potassium fluoride showed a significant reduction in the catalytic activity. Lactoperoxidase was crystallized using 200 mM ammonium nitrate and 20% PEG-3350 at pH 6.0. The crystals of LPO were soaked in the solution of potassium fluoride and used for the X-ray intensity data collection. Structure determination at 2.20 Å resolution revealed the presence of a potassium ion in the distal heme cavity. Structure determination further revealed that the propionic chain attached to pyrrole ring C of the heme moiety, was disordered into two components each having an occupancy of 0.5. One component occupied a position similar to the normally observed position of propionic chain while the second component was found in the distal heme cavity. The potassium ion in the distal heme cavity formed five coordinate bonds with two oxygen atoms of propionic moiety, Nε2 atom of His109 and two oxygen atoms of water molecules. The presence of potassium ion in the distal heme cavity hampered the catalytic activity of lactoperoxidase.


Asunto(s)
Lactoperoxidasa/metabolismo , Potasio/metabolismo , Animales , Sitios de Unión , Biocatálisis , Calcio/química , Calcio/metabolismo , Bovinos , Calostro/enzimología , Cristalografía por Rayos X , Hemo/química , Hemo/metabolismo , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Lactoperoxidasa/química , Potasio/química , Unión Proteica
6.
Front Plant Sci ; 8: 1, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28220127

RESUMEN

The present study investigates ameliorative effects of nitric oxide (NO) against zinc oxide nanoparticles (ZnONPs) phytotoxicity in wheat seedlings. ZnONPs exposure hampered growth of wheat seedlings, which coincided with reduced photosynthetic efficiency (Fv/Fm and qP), due to increased accumulation of zinc (Zn) in xylem and phloem saps. However, SNP supplementation partially mitigated the ZnONPs-mediated toxicity through the modulation of photosynthetic activity and Zn accumulation in xylem and phloem saps. Further, the results reveal that ZnONPs treatments enhanced levels of hydrogen peroxide and lipid peroxidation (as malondialdehyde; MDA) due to severely inhibited activities of the following ascorbate-glutatione cycle (AsA-GSH) enzymes: ascorbate peroxidase, glutathione reductase, monodehydroascorbate reductase and dehydroascorbate reductase, and its associated metabolites ascorbate and glutathione. In contrast to this, the addition of SNP together with ZnONPs maintained the cellular functioning of the AsA-GSH cycle properly, hence lesser damage was noticed in comparison to ZnONPs treatments alone. The protective effect of SNP against ZnONPs toxicity on fresh weight (growth) can be reversed by 2-(4carboxy-2-phenyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl-3-oxide, a NO scavenger, and thus suggesting that NO released from SNP ameliorates ZnONPs toxicity. Overall, the results of the present study have shown the role of NO in the reducing of ZnONPs toxicity through the regulation of accumulation of Zn as well as the functioning of the AsA-GSH cycle.

7.
Horm Cancer ; 4(4): 242-50, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23456391

RESUMEN

Cholecalciferol (D(3)) supplementation results in variable increases in serum 25(OH)D(3) levels, however, the influence of genetic polymorphisms on these variable responses is unclear. We measured serum 25(OH)D(3), 24,25(OH)(2)D(3), 1,25(OH)2D(3) and VDBP levels in 50 colorectal cancer (CRC) patients before and during 2,000 IU daily oral D(3) supplementation for six months and in 263 archived CRC serum samples. Serum PTH levels and PBMC 24-OHase activity were also measured during D(3) supplementation. TagSNPs in CYP2R1, CYP27A1, CYP27B1, CYP24A1, VDR, and GC genes were genotyped in all patients, and the association between these SNPs and serum vitamin D(3) metabolites levels before and after D(3) supplementation was analyzed. The mean baseline serum 25(OH)D(3) level was less than 32 ng/mL in 65 % of the 313 CRC patients. In the 50 patients receiving D(3) supplementation, serum levels of 25(OH)D(3) increased (p = 0.008), PTH decreased (p = 0.036) and 24,25(OH)(2)D(3), 1,25(OH)(2)D(3), VDBP levels and PBMC 24-OHase activity were unchanged. GC SNP rs222016 was associated with high 25(OH)D(3) and 1,25(OH)(2)D(3) levels at baseline while rs4588 and rs2282679 were associated with lower 25(OH)D(3) and 1,25(OH)(2)D(3) levels both before and after D(3) supplementation. CYP2R1 rs12794714 and rs10500804 SNPs were significantly associated with low 25(OH)D(3) levels after supplementation but not with baseline 25(OH)D(3). Our results show that D(3) supplementation increased 25(OH)D(3) levels in all patients. GC rs4588 and rs2283679 SNPs were associated with increased risk of vitamin D(3) insufficiency and suboptimal increase in 25(OH)D(3) levels after D(3) supplementation. Individuals with these genotypes may require higher D(3) supplementation doses to achieve vitamin D(3) sufficiency.


Asunto(s)
Colecalciferol/farmacocinética , Neoplasias Colorrectales/complicaciones , Esteroide Hidroxilasas/genética , Deficiencia de Vitamina D/genética , Proteína de Unión a Vitamina D/genética , Vitaminas/farmacocinética , Adulto , Anciano , Colecalciferol/administración & dosificación , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/tratamiento farmacológico , Suplementos Dietéticos , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Leucocitos Mononucleares/enzimología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Polimorfismo de Nucleótido Simple , Receptores de Calcitriol/genética , Análisis de Secuencia de ADN , Esteroide Hidroxilasas/metabolismo , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/tratamiento farmacológico , Proteína de Unión a Vitamina D/sangre , Vitamina D3 24-Hidroxilasa , Vitaminas/administración & dosificación
8.
Vaccine ; 30(6): 1083-93, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22182427

RESUMEN

Withania somnifera (Ashwagandha) is a plant with known ethnomedicinal properties and its use in Ayurvedic medicine in India is well documented. The present investigation reports on immunomodulatory efficacy of aqueous-ethanol extracts of roots of three selected Withania somnifera chemotypes designated as NMITLI 101R, NMITLI 118R and NMITLI 128R. Each chemotype was administered 10-100 mg/kg orally to BALB/c mice once daily for 14 days. The immunomodulatory consequences were recorded by determining the humoral immune response with the help of hemagglutination, plaque forming cell assay and cellular response by measuring delayed type hypersensitivity reaction. Additionally, other immune parameters such as proliferation of T and B cells, intracellular and secreted Th1 and Th2 cytokines along with modulation in ROS production by peritoneal macrophages were monitored after feeding with lower doses (3-30 mg/kg/day) of these three chemotypes individually. NMITLI 101R incited both humoral and cellular immune response in terms of higher number of antibody producing cells and enhanced foot pad swelling at the 10mg dose as also dose dependent B and T cell proliferations. Levels of intracellular and secreted cytokines post-NMITLI 101R treatment illustrated generation of mixed Th1/Th2 response that remained more polarized towards Th1. This chemotype also generated maximum reactive oxygen species. NMITLI 118R provoked comparatively reduced immune response in all humoral and cellular parameters at lower doses but induced highly polarized Th1 cytokine response. In contrast, NMITLI 128R led to enhanced antibody production with minimal cellular response demonstrating marginally Th2 dominance at a lower dose. Taken together, it may therefore be concluded that there were distinct modulation in the immune response exhibited by the three chemotypes of Withania somnifera and NMITLI 101R appeared to possess a better immunostimulatory activity than the other chemotypes at lower doses.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Formación de Anticuerpos , Inmunidad Celular , Extractos Vegetales/administración & dosificación , Withania/química , Adyuvantes Inmunológicos/aislamiento & purificación , Animales , Eritrocitos/inmunología , Femenino , India , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/aislamiento & purificación , Ovinos
9.
Proc Natl Acad Sci U S A ; 107(44): 18961-6, 2010 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-20956315

RESUMEN

It is being realized that identification of subgroups within normal controls corresponding to contrasting disease susceptibility is likely to lead to more effective predictive marker discovery. We have previously used the Ayurvedic concept of Prakriti, which relates to phenotypic differences in normal individuals, including response to external environment as well as susceptibility to diseases, to explore molecular differences between three contrasting Prakriti types: Vata, Pitta, and Kapha. EGLN1 was one among 251 differentially expressed genes between the Prakriti types. In the present study, we report a link between high-altitude adaptation and common variations rs479200 (C/T) and rs480902 (T/C) in the EGLN1 gene. Furthermore, the TT genotype of rs479200, which was more frequent in Kapha types and correlated with higher expression of EGLN1, was associated with patients suffering from high-altitude pulmonary edema, whereas it was present at a significantly lower frequency in Pitta and nearly absent in natives of high altitude. Analysis of Human Genome Diversity Panel-Centre d'Etude du Polymorphisme Humain (HGDP-CEPH) and Indian Genome Variation Consortium panels showed that disparate genetic lineages at high altitudes share the same ancestral allele (T) of rs480902 that is overrepresented in Pitta and positively correlated with altitude globally (P < 0.001), including in India. Thus, EGLN1 polymorphisms are associated with high-altitude adaptation, and a genotype rare in highlanders but overrepresented in a subgroup of normal lowlanders discernable by Ayurveda may confer increased risk for high-altitude pulmonary edema.


Asunto(s)
Adaptación Fisiológica/genética , Alelos , Genoma Humano , Polimorfismo Genético , Procolágeno-Prolina Dioxigenasa/genética , Adolescente , Adulto , Mal de Altura/genética , Femenino , Humanos , Prolina Dioxigenasas del Factor Inducible por Hipoxia , India , Masculino , Medicina Ayurvédica , Edema Pulmonar/genética
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