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1.
Tzu Chi Med J ; 36(1): 98-102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406574

RESUMO

Objectives: The objective of the study is to study the fetomaternal outcome associated with folic acid deficiency in pregnancy. Materials and Methods: This hospital-based observational study was conducted in the Department of Obstetrics and Gynaecology at Base Hospital, Delhi Cantt, and a total of 351 participants were enrolled who were fulfilling the inclusion criteria. The plasma folic acid level of the selected patients was measured in the booking visit by automated chemiluminescence assay. The cutoff levels of folic acid were taken at 8.6 ng/mL. Based on these values, the study population was divided into two groups, one with folic acid values <8.6 ng/mL and the other with values ≥8.6 ng/mL. Plasma Vitamin B12 levels were measured to check for any concurrent deficiencies. Obstetric outcomes included first- and second-trimester miscarriages, development of anemia, gestational hypertension/preeclampsia, gestational diabetes mellitus, hypothyroidism, placental abruption, and intrauterine fetal growth restriction (FGR). Furthermore, the period of gestation at delivery, fetal weights, APGAR scores at 5 min were documented. The study also considered fetal neural tube defects, intrauterine fetal demise for data collection. Collected data were analyzed statistically to find the association of the above-mentioned outcomes with levels of folic acid. Results: The rate of preterm deliveries was significantly higher in the folic acid group with levels <8.6 ng/mL (16.94%). The incidence of small for gestational age/FGR was higher in the folic acid group with levels <8.6 ng/mL (27.11%) compared to the high folic acid group with levels ≥8.6 ng/mL (13.38%). The differences in the incidence of anemia, gestational hypertension, gestational diabetes, and preeclampsia between the two groups were not statistically significant and no cases of intrauterine fetal demise or placental abruption were observed in either group. Moreover, there was no significant difference in the relative risk of low Apgar scores at 5 min between the two groups. Conclusion: The present study suggests that low folic acid levels during pregnancy are associated with a higher risk of adverse pregnancy outcomes such as anemia, miscarriages, preterm delivery, and FGR. Therefore, adherence to nutritional recommendation of folic acid supplementation during pregnancy is essential to prevent these adverse outcomes.

2.
J Pharm Bioallied Sci ; 15(Suppl 2): S1215-S1217, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694097

RESUMO

Background: Human skull consists of various bones. One of them is mandible which is quite resistant, tough and shows systemic differences in form between individuals of different sex. It resists putrefaction also. There are characteristic features in the mandible that help us to differentiate sex in case of unknown victims like in mass disasters or in case fragmentary remains of the skeleton are found. Analysis of mandible with regard to its features is of great assistance in the determination of sex. Materials and Methods: A total of 80 dry mandible bones were collected. Morphological and morphometric parameters were studied to determine their sex. A total of nine parameters, i.e., three non-metric and six metric parameters were observed for each mandible. Data was collected for each parameter. Results: Among 80 dry mandible bones, 55 were males and 25 were females. 81.2% males bones had a square chin whereas, 80% females had a rounded chin. Gonial flare was everted in 89% males and inverted in 68% females. Conclusion: Mandible exhibits significant sexual differences. Various morphological and morphometric parameters are essential for sex determination in case of mandible bone.

3.
J Med Virol ; 94(5): 1761-1765, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35014038

RESUMO

The emergence of Omicron (B.1.1.529) variant of SARS-CoV-2 has resulted into a very massive surge in COVID-19 cases worldwide. Due to continuous emergence of multiple variants of SARS-CoV-2, the ongoing pandemic has caused severe morbidity and mortality in last two years. The rate of infectivity of Omicron variant is much higher than Delta variant and in a very quick time Omicron has displaced the Delta variant and now become a dominant variant across the globe. The twin combination of Omicron and Delta variant is triggering a Tsunami wave of ever high surges in COVID-19 cases worldwide. This article highlights the global threats and challenges posed by Omicron, and strategies to counter it with a particular focus on Indian sub-continent.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/virologia , Humanos , Índia/epidemiologia , Pandemias , SARS-CoV-2/genética
4.
J Vector Borne Dis ; 57(3): 213-220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34472504

RESUMO

BACKGROUND & OBJECTIVES: In India, the burden of Plasmodium vivax malaria has been projected to be highest in some areas. This study investigated the efficacy and safety of fixed dose combination (FDC) of arterolane maleate (AM) 37.5 mg and piperaquine phosphate 187.5 mg (PQP) dispersible tablets and (not with) chloroquine in the treatment of uncomplicated vivax malaria in pediatric patients. METHODS: This multicentric, open-label trial was carried out at 12 sites in India. A total of 164 patients aged 6 months to 12 years with P. vivax malaria were randomized in a ratio of 2:1 to AM-PQP (111 patients) or chloroquine (53 patients) arms. The duration of follow up was 42 days. RESULTS: At 72 hours, the proportion of a parasitaemic and afebrile patients was 100% in both treatment arms in per protocol (PP) population, and 98.2% and 100% [95% CI: -1.8 (-6.33 to 5.08)] in AM-PQP and chloroquine arms, respectively, in intent to treat (ITT) population. The efficacy and safety of AM-PQP was found to be comparable to chloroquine in the treatment of uncomplicated P. vivax malaria in pediatric patients. Overall, the cure rate at Day 28 and 42 was >95% for both AM-PQP or CQ. The commonly reported clinical adverse event was vomiting. No patient was discontinued for any QTc abnormality. INTERPRETATION & CONCLUSION: The efficacy and safety of FDC of arterolane maleate and piperaquine phosphate was found to be comparable to chloroquine for treatment of uncomplicated P. vivax malaria in pediatric patients.


Assuntos
Antimaláricos , Malária Falciparum , Malária Vivax , Antimaláricos/efeitos adversos , Criança , Cloroquina/efeitos adversos , Cloroquina/análogos & derivados , Compostos Heterocíclicos com 1 Anel , Humanos , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Maleatos/uso terapêutico , Peróxidos , Fosfatos/uso terapêutico , Plasmodium vivax , Quinolinas , Compostos de Espiro
5.
Clin Infect Dis ; 65(10): 1711-1720, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29020247

RESUMO

BACKGROUND: Administration of artemisinin-based combination therapy (ACT) to infant and young children can be challenging. A formulation with accurate dose and ease of administration will improve adherence and compliance in children. The fixed-dose combination dispersible tablet of arterolane maleate (AM) 37.5 mg and piperaquine phosphate (PQP) 187.5 mg can make dosing convenient in children. METHODS: This multicenter (India and Africa), comparative, parallel-group trial enrolled 859 patients aged 6 months to 12 years with Plasmodium falciparum malaria. Patients were randomized in a ratio of 2:1 to AM-PQP (571 patients) once daily and artemether-lumefantrine (AL) (288 patients) twice daily for 3 days and followed for 42 days. RESULTS: The cure rate (ie, polymerase chain reaction-corrected adequate clinical and parasitological response) in the per-protocol population at day 28 was 100.0% and 98.5% (difference, 1.48% [95% confidence interval {CI}, .04%-2.91%]) in the AM-PQP and AL arms, respectively, and 96.0% and 95.8% (difference, 0.14% [95% CI, -2.68% to 2.95%]) in the intention-to-treat (ITT) population. The cure rate was comparable at day 42 in the ITT population (AM-PQP, 94.4% vs AL, 93.1%). The median parasite clearance time was 24 hours in both the arms. The median fever clearance time was 6 hours in AM-PQP and 12 hours in the AL arm. Both the treatments were found to be safe and well tolerated. Overall, safety profile of both the treatments was similar. CONCLUSIONS: The efficacy and safety of fixed-dose combination of AM and PQP was comparable to AL for the treatment of uncomplicated P. falciparum malaria in pediatric patients. CLINICAL TRIALS REGISTRATION: CTRI/2014/07/004764.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Compostos Heterocíclicos com 1 Anel/uso terapêutico , Malária Falciparum/tratamento farmacológico , Peróxidos/uso terapêutico , Quinolinas/uso terapêutico , Compostos de Espiro/uso terapêutico , África , Antimaláricos/efeitos adversos , Antimaláricos/sangue , Antimaláricos/farmacocinética , Combinação Arteméter e Lumefantrina , Artemisininas/efeitos adversos , Artemisininas/sangue , Artemisininas/farmacocinética , Criança , Pré-Escolar , Combinação de Medicamentos , Etanolaminas/efeitos adversos , Etanolaminas/sangue , Etanolaminas/farmacocinética , Feminino , Fluorenos/efeitos adversos , Fluorenos/sangue , Fluorenos/farmacocinética , Compostos Heterocíclicos com 1 Anel/efeitos adversos , Compostos Heterocíclicos com 1 Anel/sangue , Compostos Heterocíclicos com 1 Anel/farmacocinética , Humanos , Índia , Lactente , Malária Falciparum/mortalidade , Masculino , Peróxidos/efeitos adversos , Peróxidos/sangue , Peróxidos/farmacocinética , Quinolinas/efeitos adversos , Quinolinas/sangue , Quinolinas/farmacocinética , Compostos de Espiro/efeitos adversos , Compostos de Espiro/sangue , Compostos de Espiro/farmacocinética , Análise de Sobrevida , Comprimidos
6.
Front Plant Sci ; 8: 1523, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28928758

RESUMO

Mobilization of unavailable phosphorus (P) to plant available P is a prerequisite to sustain crop productivity. Although most of the agricultural soils have sufficient amounts of phosphorus, low availability of native soil P remains a key limiting factor to increasing crop productivity. Solubilization and mineralization of applied and native P to plant available form is mediated through a number of biological and biochemical processes that are strongly influenced by soil carbon/organic matter, besides other biotic and abiotic factors. Soils rich in organic matter are expected to have higher P availability potentially due to higher biological activity. In conventional agricultural systems mineral fertilizers are used to supply P for plant growth, whereas organic systems largely rely on inputs of organic origin. The soils under organic management are supposed to be biologically more active and thus possess a higher capability to mobilize native or applied P. In this study we compared biological activity in soil of a long-term farming systems comparison field trial in vertisols under a subtropical (semi-arid) environment. Soil samples were collected from plots under 7 years of organic and conventional management at five different time points in soybean (Glycine max) -wheat (Triticum aestivum) crop sequence including the crop growth stages of reproductive significance. Upon analysis of various soil biological properties such as dehydrogenase, ß-glucosidase, acid and alkaline phosphatase activities, microbial respiration, substrate induced respiration, soil microbial biomass carbon, organically managed soils were found to be biologically more active particularly at R2 stage in soybean and panicle initiation stage in wheat. We also determined the synergies between these biological parameters by using the methodology of principle component analysis. At all sampling points, P availability in organic and conventional systems was comparable. Our findings clearly indicate that owing to higher biological activity, organic systems possess equal capabilities of supplying P for crop growth as are conventional systems with inputs of mineral P fertilizers.

7.
Water Res ; 92: 22-37, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26827255

RESUMO

Pollution by metal and metalloid ions is one of the most widespread environmental concerns. They are non-biodegradable, and, generally, present high water solubility facilitating their environmental mobilisation interacting with abiotic and biotic components such as adsorption onto natural colloids or even accumulation by living organisms, thus, threatening human health and ecosystems. Therefore, there is a high demand for effective removal treatments of heavy metals, making the application of adsorption materials such as polymer-functionalized nanocomposites (PFNCs), increasingly attractive. PFNCs retain the inherent remarkable surface properties of nanoparticles, while the polymeric support materials provide high stability and processability. These nanoparticle-matrix materials are of great interest for metals and metalloids removal thanks to the functional groups of the polymeric matrixes that provide specific bindings to target pollutants. This review discusses PFNCs synthesis, characterization and performance in adsorption processes as well as the potential environmental risks and perspectives.


Assuntos
Metais/isolamento & purificação , Nanocompostos/química , Polímeros/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Água/química , Polímeros/síntese química
8.
J Reconstr Microsurg ; 28(5): 301-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22547258

RESUMO

Free flaps to the scalp, calvaria, and anterior and middle cranial fossae are typically transferred to the superficial temporal artery and vein. Occasionally the superficial temporal vein is unsuitable for microvascular anastomosis. In such cases, we have had success using the sentinel vein, a perforating vein located in the anterior aspect of the deep temporal fat pad. This article describes the pertinent anatomy, our clinical experience, and the advantages of the sentinel vein as a microsurgical recipient vessel.


Assuntos
Veias Cerebrais/anatomia & histologia , Veias Cerebrais/cirurgia , Retalhos de Tecido Biológico/irrigação sanguínea , Lobo Temporal/irrigação sanguínea , Anastomose Cirúrgica , Humanos , Microcirurgia
9.
J Reconstr Microsurg ; 27(4): 215-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21337298

RESUMO

The negative pressure dressing is a highly effective modality for coverage and bolstering of skin grafts in the early postoperative period. In the situation of a skin graft over a free flap, the surgeon might be inclined to avoid this modality out of concern that the dressing would deleteriously effect flap survival or impede flap monitoring. This case series supports the safety of the negative pressure dressing and demonstrates a technical modification that permits external Doppler monitoring of the flap through the dressing. Thus, this technique provides an ideal environment for skin graft healing while maintaining the ability to monitor the flap in a straightforward manner and also simplifies nursing care.


Assuntos
Retalhos de Tecido Biológico/irrigação sanguínea , Tratamento de Ferimentos com Pressão Negativa , Procedimentos de Cirurgia Plástica/métodos , Ultrassonografia Doppler/métodos , Ferimentos e Lesões/cirurgia , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Cuidados Pós-Operatórios/métodos , Procedimentos de Cirurgia Plástica/efeitos adversos , Estudos Retrospectivos , Estudos de Amostragem , Fatores de Tempo , Cicatrização/fisiologia , Ferimentos e Lesões/diagnóstico , Adulto Jovem
10.
Clin Drug Investig ; 29(9): 559-75, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19663519

RESUMO

BACKGROUND AND OBJECTIVE: Advanced glycation end-products (AGEs) have been implicated in the pathogenesis of diabetic complications through a variety of mechanisms including endothelial dysfunction and structural abnormalities in the vasculature and myocardium. Reducing the AGEs burden and their ensuing pro-inflammatory, pro-oxidative and pro-coagulant effect with associated dysfunctional proteins in various target tissues may retard the progression of and even reverse diabetic macro- and microvascular complications. Pyridinium, 3-[[2-(methylsulfonyl) hydrazino] carbonyl]-1-[2-oxo-2-2-thienyl) ethyl]-chloride (TRC4186) has demonstrated AGE-breaking activities in in vitro experiments and improvement in the endothelial and myocardial function in animal models of diabetes mellitus with reduction of AGEs accumulation in tissues over time. The safety of TRC4186 has been established in in vitro and in vivo preclinical studies. Thus, this drug is being developed for the treatment of complications associated with diabetes. This investigation set out to evaluate the safety, tolerability and pharmacokinetics of TRC4186 in healthy human subjects after single and multiple ascending doses, fixed doses in elderly male and female subjects, and with food and different formulations of the compound. METHODS: Four studies were conducted during phase I clinical development of TRC4186. These were: (i) a randomized, double-blind, placebo-controlled, single-dose, dose-ascending study in healthy male subjects with doses of TRC4186 ranging from 250 to 2500 mg administered as an oral solution (total six doses); (ii) a randomized, double-blind, placebo-controlled, multiple-dose, dose-ascending study in healthy male subjects with three doses of TRC4186 ranging from 500 to 2000 mg twice daily for 6 days with a final single dose on day 7; (iii) a randomized, open-label, three-way crossover study to assess the effect of food (fasted vs fed) and formulation (solution vs tablet) with TRC4186 500 mg; (iv) a randomized, double-blind, placebo-controlled, single-dose, dose-ascending study in elderly male and female subjects at a dose of TRC4186 500 mg followed by TRC4186 1000 mg after a 7-day washout period. The safety and tolerability of TRC4186 were assessed by considering adverse events (AEs), ECG findings, vital signs and laboratory investigation results. RESULTS: TRC4186 was rapidly absorbed, with maximum plasma concentrations (C(max)) attained within 1-4 hours. C(max) and area under the plasma concentration-time curve (AUC) were dose proportional over the range 250-2500 mg for a single dose and 500-2000 mg for multiple doses with twice-daily administration. Steady-state conditions were attained within 6 days at different dose levels. C(max) and AUC were not affected by age, sex, race or type of formulation. The tablet formulation of TRC4186 was bioequivalent with the solution form of the drug under fasting conditions and systemic availability of the tablet formulation was reduced by 40% when administered under fed conditions. Terminal elimination and renal clearance in the elderly male (age 69.1 +/- 6.0 years) were not significantly different compared with younger subjects (age 31 +/- 8.6 years). CONCLUSION: TRC4186 was safe and well tolerated when administered orally with either a single or multiple doses across the different ages, sexes, races and formulations studied. A dose-proportional increase in plasma TRC4186 concentration was seen, with steady state being achieved within 6 days.


Assuntos
Produtos Finais de Glicação Avançada/antagonistas & inibidores , Compostos de Piridínio/administração & dosagem , Sulfonamidas/administração & dosagem , Adolescente , Adulto , Fatores Etários , Idoso , Formas de Dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Avaliação de Medicamentos , Eletrocardiografia/efeitos dos fármacos , Feminino , Interações Alimento-Droga , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Piridínio/efeitos adversos , Compostos de Piridínio/farmacocinética , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Equivalência Terapêutica
11.
Bioorg Med Chem Lett ; 18(20): 5563-6, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18815032

RESUMO

Synthesis of 4-amino-4,6-androstadiene-3,17-dione 7, an analog of formestane used in breast cancer therapy as an aromatase inhibitor, from 4-acetoxy-4-androstene-3,17-dione 2 is described. This is the first report of a 4-amino diene (4,6) system in this series of molecules. The new (7) and reported molecules were screened by the National Cancer Institute (NCI, Bethesda, USA) for in vitro antitumor activity against 60 human cancer cell lines. Molecule 7 showed best activity against breast cancer cell line (MCF-7).


Assuntos
Androstadienos/química , Androstenodiona/análogos & derivados , Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Química Farmacêutica/métodos , Androstenodiona/síntese química , Androstenodiona/química , Androstenodiona/farmacologia , Antineoplásicos/farmacologia , Aromatase/metabolismo , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Químicos
12.
J Biol Chem ; 283(27): 18821-31, 2008 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-18456663

RESUMO

SGK-1 (serum- and glucocorticoid-regulated kinase-1), a member of the AGC protein kinase family, plays an important role in regulating ion channel expression and contributes to malignant epithelial cell proliferation and survival. SGK-1 activity is regulated on three levels: transcriptional induction following a variety of environmental and intracellular stresses, proteasomal degradation, and phosphorylation. Here we report that phosphoinositide 3-kinase (PI3K)-dependent phosphorylation of SGK-1 requires formation of a complex between SGK-1 and heat-shock protein 90 (Hsp90). Inactivation of Hsp90 by geldanamycin led to decreased SGK-1 phosphorylation independently of increased proteasomal protein degradation, and inhibition of PI3K activity by LY294002 appeared to eliminate SGK-1 phosphorylation at the same residues as those affected by geldanamycin treatment. Interestingly, geldanamycin-targeted phosphorylation sites were not limited to the known conserved PI3K-dependent sites Thr-256 and Ser-422 in SGK-1 but included additional unknown PI3K-dependent residues. Inhibition of Hsp90 also resulted in a complete loss of SGK-1 kinase activity, suggesting that Hsp90 activity is essential for regulating the PI3K/SGK-1 pathway.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Benzoquinonas/farmacologia , Células COS , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP90/genética , Humanos , Proteínas Imediatamente Precoces/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Morfolinas/farmacologia , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias Epiteliais e Glandulares/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores
13.
Nat Chem Biol ; 4(4): 241-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18344977

RESUMO

Our understanding of how steroid hormones regulate physiological functions has been significantly advanced by structural biology approaches. However, progress has been hampered by misfolding of the ligand binding domains in heterologous expression systems and by conformational flexibility that interferes with crystallization. Here, we show that protein folding problems that are common to steroid hormone receptors are circumvented by mutations that stabilize well-characterized conformations of the receptor. We use this approach to present the structure of an apo steroid receptor that reveals a ligand-accessible channel allowing soaking of preformed crystals. Furthermore, crystallization of different pharmacological classes of compounds allowed us to define the structural basis of NFkappaB-selective signaling through the estrogen receptor, thus revealing a unique conformation of the receptor that allows selective suppression of inflammatory gene expression. The ability to crystallize many receptor-ligand complexes with distinct pharmacophores allows one to define structural features of signaling specificity that would not be apparent in a single structure.


Assuntos
Compostos Bicíclicos com Pontes/química , NF-kappa B/química , Pirazóis/química , Pirimidinas/química , Receptores de Estrogênio/química , Sítios de Ligação , Compostos Bicíclicos com Pontes/farmacologia , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Mutação , NF-kappa B/efeitos dos fármacos , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Pirazóis/farmacologia , Pirimidinas/farmacologia , Receptores de Estrogênio/agonistas , Sensibilidade e Especificidade , Transdução de Sinais , Relação Estrutura-Atividade
14.
Steroids ; 73(1): 59-68, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17949766

RESUMO

Conjugated equine estrogens (CEEs) are routinely used for hormone replacement therapy (HRT), making it important to understand the activities of individual estrogenic components. Although 17beta-estradiol (17beta-E2), the most potent estrogen in CEE, has been extensively characterized, the actions of nine additional less potent estrogens are not well understood. Structural differences between CEEs and 17beta-E2 result in altered interactions with the two estrogen receptors (ERalpha and ERbeta) and different biological activities. To better understand these interactions, we have determined the crystal structure of the CEE analog, 17beta-methyl-17alpha-dihydroequilenin (NCI 122), in complex with the ERalpha ligand-binding domain and a peptide from the glucocorticoid receptor-interacting protein 1 (GRIP1) coactivator. NCI 122 has chemical properties, including an unsaturated B-ring and 17alpha-hydroxyl group, which are shared with some of the estrogens found in CEEs. Structural analysis of the NCI 122-ERalpha LBD-GRIP1 complex, combined with biochemical and cell-based comparisons of CEE components, suggests that factors such as decreased ligand flexibility, decreased ligand hydrophobicity and loss of a hydrogen bond between the 17-hydroxyl group and His524, contribute significantly to the reduced potency of CEEs on ERalpha.


Assuntos
Estrogênios Conjugados (USP)/química , Estrogênios/química , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Dimerização , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/química , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Estrogênios Conjugados (USP)/metabolismo , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica , Receptores Androgênicos/química , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transcrição Gênica
15.
Bioorg Med Chem Lett ; 17(14): 4066-9, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17502140

RESUMO

8-Iodo-11-(4-methylpiperazino)-5H-dibenzo[b,e][1,4]-diazepine: Iozapine, a potential D(4)-receptor ligand was synthesized using oxidative iodo-destannylation reaction. The preliminary biodistribution studies of radioiodinated iozapine have shown that the compound is taken up in the brains of mice and rabbits.


Assuntos
Encéfalo/metabolismo , Clozapina/análogos & derivados , Animais , Clozapina/síntese química , Clozapina/metabolismo , Clozapina/farmacocinética , Camundongos , Coelhos , Receptores de Dopamina D4/metabolismo , Distribuição Tecidual
16.
J Nucl Med Technol ; 34(3): 169-73, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16951286

RESUMO

UNLABELLED: Radiation doses to the fingers of occupational workers handling 99mTc-labeled compounds and 131I for diagnostic and therapeutic procedures in nuclear medicine were measured by thermoluminescence dosimetry. METHODS: The doses were measured at the base of the ring finger and the index finger of both hands in 2 groups of workers. Group 1 (7 workers) handled 99mTc-labeled radiopharmaceuticals, and group 2 (6 workers) handled 131I for diagnosis and therapy. Radiation doses to the fingertips of 3 workers also were measured. Two were from group 1, and 1 was from group 2. RESULTS: The doses to the base of the fingers for the radiopharmacy staff and physicians from group 1 were observed to be 17+/-7.5 (mean+/-SD) and 13.4+/-6.5 microSv/GBq, respectively. Similarly, the dose to the base of the fingers for the 3 physicians in group 2 was estimated to be 82.0+/-13.8 microSv/GBq. Finger doses for the technologists in both groups could not be calculated per unit of activity because they did not handle the radiopharmaceuticals directly. Their doses were reported in millisieverts that accumulated in 1 wk. The doses to the fingertips of the radiopharmacy worker and the physician in group 1 were 74.3+/-19.8 and 53.5+/-21.9 microSv/GBq, respectively. The dose to the fingertips of the physician in group 2 was 469.9+/-267 microSv/GBq. CONCLUSION: The radiation doses to the fingers of nuclear medicine staff at our center were measured. The maximum expected annual dose to the extremities appeared to be less than the annual limit (500 mSv/y), except for a physician who handled large quantities of 131I for treatment. Because all of these workers are on rotation and do not constantly handle radioactivity throughout the year, the doses to the base of the fingers or the fingertips should not exceed the prescribed annual limit of 500 mSv.


Assuntos
Dedos , Serviço Hospitalar de Medicina Nuclear , Exposição Ocupacional/análise , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Compostos Radiofarmacêuticos/análise , Medição de Risco/métodos , Carga Corporal (Radioterapia) , Humanos , Índia , Doses de Radiação , Radioisótopos/análise , Eficiência Biológica Relativa
17.
J Biol Chem ; 281(26): 17909-19, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16648639

RESUMO

Estrogen receptors alpha (ERalpha) and beta (ERbeta) have distinct functions and differential expression in certain tissues. These differences have stimulated the search for subtype-selective ligands. Therapeutically, such ligands offer the potential to target specific tissues or pathways regulated by one receptor subtype without affecting the other. As reagents, they can be utilized to probe the physiological functions of the ER subtypes to provide information complementary to that obtained from knock-out animals. A fluorescence resonance energy transfer-based assay was used to screen a 10,000-compound chemical library for ER agonists. From the screen, we identified a family of ERbeta-selective agonists whose members contain bulky oxabicyclic scaffolds in place of the planar scaffolds common to most ER ligands. These agonists are 10-50-fold selective for ERbeta in competitive binding assays and up to 60-fold selective in transactivation assays. The weak uterotrophic activity of these ligands in immature rats and their ability to stimulate expression of an ERbeta regulated gene in human U2OS osteosarcoma cells provides more physiological evidence of their ERbeta-selective nature. To provide insight into the molecular mechanisms of their activity and selectivity, we determined the crystal structures of the ERalpha ligand-binding domain (LBD) and a peptide from the glucocorticoid receptor-interacting protein 1 (GRIP1) coactivator complexed with the ligands OBCP-3M, OBCP-2M, and OBCP-1M. These structures illustrate how the bicyclic scaffolds of these ligands are accommodated in the flexible ligand-binding pocket of ER. A comparison of these structures with existing ER structures suggests that the ERbeta selectivity of OBCP ligands can be attributed to a combination of their interactions with Met-336 in ERbeta and Met-421 in ERalpha. These bicyclic ligands show promise as lead compounds that can target ERbeta. In addition, our understanding of the molecular determinants of their subtype selectivity provides a useful starting point for developing other ER modulators belonging to this relatively new structural class.


Assuntos
Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/agonistas , Receptor beta de Estrogênio/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/química , Receptor beta de Estrogênio/genética , Feminino , Genisteína/química , Genisteína/metabolismo , Inibidores do Crescimento/química , Inibidores do Crescimento/metabolismo , Humanos , Ligantes , Metionina/metabolismo , Osteossarcoma , Fenol/química , Fenol/metabolismo , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/metabolismo , Transfecção , Útero/fisiologia
18.
Brain Res ; 1064(1-2): 119-25, 2005 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-16298351

RESUMO

Vagotomy and capsaicin treatment attenuate dorsal vagal complex (DVC) but not myenteric Fos-like immunoreactivity (Fos-LI) induced by cholecystokinin-8 (CCK-8). The goal of this experiment is to test the role of the sympathetic nervous system in the pathway by which CCK-8 increases myenteric Fos-LI. Adult male Sprague-Dawley rats were pretreated with guanethidine sulfate (40 mg/kg daily for 5 weeks) or vehicle intraperitoneally (IP), and injected with CCK-8 (40 microg/kg) or saline IP. Fos-LI was then quantified in the DVC and the myenteric neurons of the duodenum and jejunum using a diaminobenzidine reaction. Guanethidine pretreatment attenuated myenteric but not DVC Fos-LI induced by CCK-8. These findings demonstrate that sympathetic neurons play a role in mediating the myenteric Fos-LI response to CCK. They also suggest differential mediation of myenteric and DVC responses to CCK.


Assuntos
Colecistocinina/fisiologia , Plexo Mientérico/metabolismo , Fragmentos de Peptídeos/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fibras Simpáticas Pós-Ganglionares/metabolismo , Nervo Vago/metabolismo , Análise de Variância , Animais , Guanetidina/farmacologia , Imuno-Histoquímica , Masculino , Plexo Mientérico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Simpatectomia Química , Fibras Simpáticas Pós-Ganglionares/efeitos dos fármacos , Simpatolíticos/farmacologia , Vagotomia , Nervo Vago/efeitos dos fármacos
19.
Am J Vet Res ; 66(8): 1308-13, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16173470

RESUMO

OBJECTIVE: To evaluate the role of cholecystokinin (CCK)-receptor antagonists in the activation of enteric and hindbrain neurons by sulfated CCK-8. ANIMALS: 81 male Sprague-Dawley rats. PROCEDURE: Rats were allocated to 10 groups (5 to 22 rats/group). Each rat received 2 IP injections (15 minutes between injections). The first injection consisted of a specific CCK2-receptor (CCK2R) antagonist (L365,260; 150, 500, or 1,000 microg/kg), a specific CCK1-receptor (CCK1R) antagonist (devazepide; 150 microg/kg), or 1% dimethyl sulfoxide (DMSO [ie, vehicle]), and the second injection consisted of sulfated CCK-8 (10 microg/kg) or saline (0.9% NaCl) solution. Rats were anesthetized and perfused with 500 mL of Krebs saline solution, and the myenteric plexuses of the duodenum and jejunum were collected. Rats were then perfused with 500 mL of phosphate-buffered 4% formaldehyde solution; rats were then euthanatized, and the hindbrain of each was harvested. Tissues were stained by use of a diaminobenzidine reaction enhanced with nickel to reveal Fos-like immunoreactivity (Fos-LI), a marker of neuronal activation, in the aforementioned neurons. RESULTS: Sulfated CCK-8 significantly increased Fos-LI in the myenteric and hindbrain neurons, compared with values for the DMSO injections. All dosages of L365,260 failed to attenuate this increase; however, injection of devazepide attenuated the increase in Fos-LI. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the results of this study reveals that sulfated CCK-8 activates myenteric and hindbrain neurons of rats primarily through CCK1 R. It provides evidence that CCK2R are lacking or not functional in the gastrointestinal tract of rats.


Assuntos
Plexo Mientérico/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Receptores da Colecistocinina/fisiologia , Rombencéfalo/metabolismo , Sincalida/análogos & derivados , Animais , Expressão Gênica/efeitos dos fármacos , Masculino , Plexo Mientérico/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores da Colecistocinina/antagonistas & inibidores , Rombencéfalo/efeitos dos fármacos , Sincalida/farmacologia
20.
Brain Res ; 1058(1-2): 109-19, 2005 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-16169531

RESUMO

We utilized a diaminobenzidine reaction enhanced with nickel to compare dorsal vagal complex (DVC) and myenteric neuronal Fos-Like immunoreactivity (Fos-LI), in response to sulfated cholecystokinin-8 (CCK-8) (5, 10, 20, 40 microg/kg), among Sprague-Dawley (SD), Standard Long-Evans (SLE), Otsuka Long-Evans Tokushima Fatty (OLETF), and Long-Evans Tokushima Otsuka (LETO) rats. All rat strains but OLETF expressed Fos-LI in response to CCK-8. In addition, SD rats expressed more Fos-LI in the area postrema and myenteric neurons than SLE and LETO rats. To investigate the basis for these differences, we utilized cuprolinic blue staining, which stains neuronal cell bodies, to quantify the number of myenteric neurons, and a reverse transcriptase chain polymerase reaction to measure the gene expression of CCK(1) receptor in the gut. We found that SD rats have significantly more duodenal myenteric neurons than the other strains. In addition, this strain expressed significantly higher levels of the CCK(1) gene in both the duodenum and jejunum than the other strains. In conclusion, SD rats may express more myenteric Fos-LI in response to CCK due to increased numbers of myenteric neurons or more intestinal CCK(1) receptors than the other strains of rats.


Assuntos
Colecistocinina/metabolismo , Regulação da Expressão Gênica/genética , Plexo Mientérico/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Receptores da Colecistocinina/genética , Receptores da Colecistocinina/metabolismo , Animais , Contagem de Células , Colecistocinina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Plexo Mientérico/citologia , Plexo Mientérico/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos OLETF , Ratos Long-Evans , Ratos Sprague-Dawley , Sincalida/metabolismo , Sincalida/farmacologia , Especificidade da Espécie
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