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1.
Sci Rep ; 11(1): 16770, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408165

RESUMO

In water scarce regions of South Asia, diversification of rice with maize is being advocated towards sustainability of cereal-based cropping systems. Adoption of innovative agronomic management practices, i.e., conservation agriculture (CA) and sub-surface drip irrigation (SSDI) are considered as key strategies for much needed interventions to address the challenges of water scarcity under projected climate change. Benefits from CA and SSDI concerning water economy are well-established, however, information about their complementarity and water budgeting in cereal-based systems are lacking. A field study was conducted with process-based model (HYDRUS-2D) to understand water transport, root water uptake and components of soil water balance in maize grown in rotation with wheat after five years of continuous adoption of conservation agriculture. In this study, altogether eight treatments comprising of 6 CA+ treatments (CA coupled with SSDI); permanent beds using sub-surface drip (PB-SSD) with (WR) and without (WOR) crop residue at different N rates, 0, 120 and 150 kg N ha-1 were compared with CA (PB using furrow irrigation-FI with crop residue-120 kg N ha-1) and conventional tillage practices (CT) (CT using FI without crop residue-120 kg N ha-1). Results showed that the model could simulate the daily changes in profile soil water content with reasonable accuracy in all the treatments. Simulated soil water balance indicated higher cumulative root water uptake (CRWU), lower cumulative evaporation (CE) and higher soil water retention in CA+ (PB-SSD+ crop residue at 150 and 120 kg N ha-1) than CA and CT plots. Hydrus-2D model efficiency > 0, RMSE between 0.009-0.026 and R2 value between 0.80-0.92 at P < 0.01 indicates that the model is performing efficiently. The mean evaporation from CA+ treatments was 10 and 36% less than CA and CT treatments, respectively. On average, CRWU under CA+ treatments were 14-48% higher than FI treatments. The mean cumulative deep drainage in CA+ plots was 80-100 mm less than CA and CT plots. In CA+ based plots significantly higher biomass production and radiation use efficiency were observed with reduced water use than CA and CT. Therefore, the study justifies the water-saving nature of CA+, while maintaining higher productivity and meeting the transpiration demand of crops and halting unnecessary evaporation and deep drainage losses.

2.
Theriogenology ; 139: 167-177, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31419703

RESUMO

Kisspeptin (Kiss1), neurokinin-B (NKB) and dynorphin (Dyn) neurons regulate the surge and pulsatile centres of gonadotropin releasing hormone (GnRH) in the hypothalamus and are modulated by the ovarian steroids. Accordingly, we studied the temporospatial expression of Kiss1, its receptor and other genes that regulate GnRH in the preoptic area (POA) and arcuate (ARC) regions of hypothalamus at different phases of bubaline estrous cycle. Brain of buffalo (n = 32) was collected immediately after exsanguination and categorized into early luteal (EL), mid luteal (ML), follicular (FL) stages and acyclic (n = 8/group). Total RNA was extracted from the POA and ARC of each stage and real time PCR amplification of Kiss1, Kiss1r, NKB, NKB receptor (NKBR), Dyn, Dyn receptor (OPRK1), GnRH1, ERα, PR, LEPR and GHSR was done using GAPDH as endogenous control and acyclic stage as calibrator group. Further, immunolocalization of Kiss1 and Kiss1r was done on the hypothalamus. In the POA, significant up-regulation of Kiss1 and NKB with a concomitant down-regulation of Dyn transcripts was recorded at FL stage. There was, however, down-regulation of Kiss1 and Kiss1r during the EL perhaps due to the loss of estradiol as a consequence of ovulation. On the other hand, in the ARC, there was a significant up-regulation of Kiss1 and Dyn at FL and ML, while NKB transcript was consistently down-regulated at any stage of estrous cycle. In the POA, expression of ERα was not modulated; however, PR was down-regulated in the EL. In the ARC, the ERα expression was significantly up-regulated in the EL, whereas, PR was moderately expressed irrespective of the stage of estrous cycle. The immunolocalization study revealed the presence of Kiss1 and Kiss1r in the POA and ARC in the cyclic buffalo with relative abundance at FL. The transcriptional profile of the genes suggests that there is estrous cycle stage specific expression of Kiss1, Kiss1r and other GnRH regulating genes in the POA and ARC regions of hypothalamus in the buffalo. Up-regulation of Kiss1r in the POA during ML and ARC during EL indicates the involvement of kisspeptinergic system in the regulation of low LH pulse frequencies during the early and mid luteal phases in the cyclic buffalo.


Assuntos
Búfalos , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Receptores de Kisspeptina-1/metabolismo , Animais , Estro/metabolismo , Feminino , Kisspeptinas/genética , Receptores de Kisspeptina-1/genética
3.
Sci Total Environ ; 640-641: 1382-1392, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30021305

RESUMO

Given the increasing scarcity of production resources such as water, energy and labour coupled with growing climatic risks, maize-based production systems could be potential alternatives to intensive rice-wheat (RW) rotation in western Indo-Gangetic Plains (IGP). Conservation agriculture (CA) in maize systems has been widely promoted for minimizing soil degradation and ensuring sustainability under emerging climate change scenario. Such practices are also believed to provide mitigation co-benefits through reduced GHG emission and increased soil carbon sequestration. However, the combined effects of diversified crop rotations and CA-based management on GHG mitigation potential and other co-benefits are generally over looked and hence warrant greater attention. A field trial was conducted for 5-years to assess the changes in soil organic carbon fractions, mineral-N, N2O emission and global warming potential (GWP) of maize-based production systems under different tillage & crop establishment methods. Four diversified cropping systems i.e. maize-wheat-mungbean (MWMb), maize-chickpea-Sesbania (MCS), maize-mustard-mungbean (MMuMb) and maize-maize-Sesbania (MMS) were factorially combined with three tillage & crop establishment methods i.e. zero tilled permanent beds (PB), zero-tillage flat (ZT) and conventional tillage (CT) in a split-plot design. After 5-years of continued experimentation, we recorded that across the soil depths, SOC content, its pools and mineral-N fractions were greatly affected by tillage & crop establishment methods and cropping systems. ZT and PB increased SOC stock (0-30 cm depth) by 7.22-7.23 Mg C ha-1 whereas CT system increased it only by 0.88 Mg C ha-1as compared to initial value. Several researchers reported that SOC & mineral-N fraction contents in the top 30 cm soil depth are correlated with N2O-N emission. In our study, global warming potential (GWP) under CT system was higher by 18.1 and 17.4%, compared to CA-based ZT and PB, respectively. Among various maize systems, GWP of MMS were higher by 11.2, 6.7 and 6.6%, compared that of MWMb (1212 kg CO2-eq. ha-1), MCS (1274 kg CO2-eq. ha-1) and MMuMb (1275 kg CO2-eq. ha-1), respectively. The results of our study suggest that CA and diversified crop rotations should be promoted in north-western IGP and other similar agro-ecologies across the globe for ensuring food security, restoration of soil health and climate change mitigation, the key sustainable development goals (SDGs).


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Solo/química , Carbono/análise , Produtos Agrícolas , Índia , Minerais , Nitrogênio/análise , Óxido Nitroso/análise , Zea mays/crescimento & desenvolvimento
4.
Natl Med J India ; 24(3): 151-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21786844

RESUMO

Lithium-induced cardiotoxicity, though rare at therapeutic levels, has been reported frequently in overdoses. We report a patient who developed sinus bradycardia while being treated with lithium carbonate even though the serum lithium levels were within the therapeutic range. It reversed following withdrawal of lithium and did not reappear with subsequent treatment with valproate.


Assuntos
Antimaníacos/efeitos adversos , Compostos de Lítio/efeitos adversos , Lítio/sangue , Síndrome do Nó Sinusal/induzido quimicamente , Sulfatos/efeitos adversos , Adulto , Antimaníacos/uso terapêutico , Humanos , Compostos de Lítio/uso terapêutico , Masculino , Sulfatos/uso terapêutico
5.
Indian J Nephrol ; 21(2): 112-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21769174

RESUMO

Data on non-infectious complications of continuous ambulatory peritoneal dialysis (CAPD) are sparingly reported from different centres of the country. We studied the non-infectious complications in patients of end stage-renal disease (ESRD) undergoing CAPD. Double-cuffed straight catheter was inserted in all patients using the surgical method and CAPD was started on the 15(th) day of catheter insertion. The nature of non-infectious complications was noted during follow-up in these patients. Forty-five (male 31, female 14) patients with the mean age of 54.5±11.6 years were studied. Diabetic nephropathy was the most common (59.5%) cause of ESRD. Overall, non-infectious complications were noted in 18/45 (40%) cases. Ultrafiltration failure was the most common (15.5%) followed by incisional hernia (6.6%), exit site leak (4.4%), hydrothorax (4.4%), catheter malposition (4.4%), scrotal swelling (2.2%) and hemoperitoneum (2.2%). Patients with ultrafiltration failure were either shifted to hemodialysis or underwent renal transplantation. The remaining (62%) non-infectious complications did not affect the catheter survival and CAPD could be continued. Non-infectious complications occurred in 40% of our CAPD patients and ultrafiltration failure was the most common (15.5%). A majority (62%) of the complications did not affect catheter survival.

6.
Curr Med Chem ; 18(14): 2174-85, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21521163

RESUMO

Lymphatic filariasis, onchocerciasis and loiasis caused by human filarial nematodes are diseases of tropical and subtropical countries causing considerable morbidity. The available control strategies have significant limitations such that current drugs are ineffective against macrofilariae (adult worms), require repeated and prolonged treatment over years and are threatened by emergence of drug resistance. Due to this concern, these diseases are the focus of renewed scientific interest and much has been done in filariasis research in the past decade. This review summarizes the current status of filariasis, different control strategies, recent advances in antifilarial chemotherapy including currently used drugs, their pros and cons, their mechanism of action, and recently discovered targets and prototypes.


Assuntos
Descoberta de Drogas/tendências , Filariose/tratamento farmacológico , Filaricidas/química , Filaricidas/uso terapêutico , Filarioidea/efeitos dos fármacos , Animais , Descoberta de Drogas/métodos , Filariose/prevenção & controle , Filaricidas/farmacologia , Humanos
8.
Bioresour Technol ; 100(13): 3293-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19297151

RESUMO

Fermentation of acid hydrolysate of water-hyacinth (Eichhornia crassipes), a free floating aquatic plant has been investigated for ethanol production. The dilute acid treatment has been applied to utilize the maximum hemicellulosic content of the water-hyacinth. The goal of this work was to investigate, both experimentally and theoretically using mathematical tools, a fermentative system utilizing water-hyacinth (Eichhornia crassipes) hemicellulose acid hydrolysate as a substrate for ethanol production using Pichia stipitis. It was found that 72.83% of xylose was converted to ethanol with a yield of 0.425 g(p)/g(s) and productivity of 0.176 g(p)/L/h. An appropriate mathematical model was developed to explain theoretically the bioconversion of this hemicellulose acid hydrolysate to ethanol and the model was tested statistically to check the validity of the model.


Assuntos
Biotecnologia/métodos , Eichhornia/metabolismo , Etanol/síntese química , Etanol/metabolismo , Fermentação , Oxigênio/metabolismo , Pichia/metabolismo , Plantas/metabolismo , Polissacarídeos/metabolismo , Biomassa , Etanol/análise , Gasolina , Hidrólise , Cinética , Oxigênio/farmacologia , Pichia/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Assoc Physicians India ; 52: 743-5, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15839455

RESUMO

Three cases of acute renal failure following consumption of raw grass gall bladder are reported here from NE State, Manipur.


Assuntos
Peixes , Doenças Transmitidas por Alimentos/complicações , Necrose Tubular Aguda/etiologia , Toxinas Marinhas/intoxicação , Adolescente , Adulto , Animais , Bile , Carpas , Criança , Água Doce , Humanos , Índia , Masculino
10.
Dermatology ; 203(2): 157-61, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11586016

RESUMO

BACKGROUND: Recent evidence indicates that acute stress can precipitate a number of dermatological conditions, including alopecia areata. This effect may be mediated by corticotropin-releasing hormone (CRH) released locally in the skin from dorsal root ganglia or immune cells. CRH typically acts through activation of specific receptors that are either type 1 or types 2 alpha and 2 beta. CRH, or related peptides such as urocortin, could have proinflammatory effects directly or through activation of mast cells leading to destruction of the hair root. OBJECTIVES: To investigate the expression of CRH receptors on the affected skin of patients who developed alopecia areata following acute emotional stress. METHODS: Scalp skin biopsies were obtained from 1 normal volunteer and 3 patients after ring infiltration of the relevant site with lidocaine. The biopsies were frozen and were later processed for in situ hybridization for CRH receptors type 1 or types 2 alpha and 2 beta. Sections showing positive results were photographed. RESULTS: The skin from the normal volunteer showed weak background expression of all three receptor types. However, skin from the affected sites of all 3 patients studied showed intense expression only on the type 2 beta receptor around the hair follicles. CONCLUSION: Acute emotional stress may precipitate alopecia areata by activation of overexpressed type 2 beta CRH receptors around the hair follicles leading to intense local inflammation.


Assuntos
Alopecia em Áreas/etiologia , Hormônio Liberador da Corticotropina/genética , Pele/metabolismo , Estresse Psicológico/complicações , Adulto , Alopecia em Áreas/genética , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica , Folículo Piloso/metabolismo , Humanos , Hibridização In Situ , Masculino , RNA/genética , RNA/metabolismo , Regulação para Cima
11.
Brain Behav Immun ; 13(3): 225-39, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10469524

RESUMO

Many skin disorders, such as atopic dermatitis and psoriasis, worsen during stress and are associated with increased numbers and activation of mast cells which release vasoactive, nociceptive, and proinflammatory mediators. Nontraumatic acute psychological stress by immobilization has been shown to induce mast cell degranulation in the rat dura and colon. Moreover, intradermal injection of corticotropin-releasing hormone (CRH) or its analogue urocortin (10(-5)-10(-7) M) induced skin mast cell degranulation and increased vascular permeability. Here, we investigated the effect of acute immobilization stress on skin mast cell degranulation by light microscopy and electron microscopy. Immobilization for 30 min resulted (P < 0.05) in degranulation of 40.7 +/- 9.1% of skin mast cells compared to 22.2 +/- 7.3% in controls killed by CO(2) or 17.8 +/- 2.4% in controls killed by pentobarbital. Pretreatment intraperitoneally (ip) with antiserum to CRH for 60 min prior to stress reduced (P < 0.05) skin mast cell degranulation to 21.0 +/- 3. 3%. Pretreatment with the neurotensin (NT) receptor antagonist SR48692 reduced (P < 0.05) mast cell degranulation to 12.5 +/- 3.4%, which was significantly (P < 0.05) below control levels. In animals treated neonatally with capsaicin to deplete their sensory neurons of their neuropeptides, such as substance P (SP), mast cell degranulation due to immobilization stress was reduced to about 15%. This is the first time that stress has been shown to trigger skin mast cell degranulation, an action not only dependent on CRH, but apparently also involving NT and SP. These findings may have implications for the pathophysiology and possible therapy of neuroinflammatory skin disorders such as atopic dermatitis, neurogenic pruritus, or psoriasis, which are induced or exacerbated by stress.


Assuntos
Degranulação Celular/imunologia , Mastócitos/imunologia , Neuropeptídeos/imunologia , Psoríase/imunologia , Estresse Fisiológico/imunologia , Doença Aguda , Animais , Anticorpos/farmacologia , Capsaicina/farmacologia , Hormônio Liberador da Corticotropina/imunologia , Masculino , Mastócitos/ultraestrutura , Microscopia Eletrônica , Microtomia , Inflamação Neurogênica/imunologia , Inflamação Neurogênica/patologia , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/imunologia , Neurotensina/imunologia , Psoríase/patologia , Pirazóis/farmacologia , Quinolinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Neurotensina/antagonistas & inibidores , Restrição Física , Pele/imunologia , Pele/patologia , Substância P/imunologia , Urticária/imunologia , Urticária/patologia
12.
J Pharmacol Exp Ther ; 288(3): 1349-56, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10027877

RESUMO

Urocortin (Ucn) is related to corticotropin-releasing hormone (CRH), and both are released in the brain under stress where they stimulate CRH 1 and 2 receptors (CRHR). Outside the brain, they may have proinflammatory actions through activation of mast cells, which are located perivascularly close to nerve endings and degranulate in response to acute psychological stress. Here, we report that a concentration of intradermal Ucn as low as 10 nM induced dose-dependent rat skin mast cell degranulation and increased vascular permeability. This effect appeared to be equipotent to that of calcitonin gene-related peptide and neurotensin. Ucn-induced skin vasodilation was inhibited by pretreatment with the mast cell stabilizer disodium cromoglycate (cromolyn) and was absent in the mast cell-deficient W/Wv mice. The selective nonpeptide CRH receptor 1 antagonist, antalarmin and the nonselective peptide antagonist astressin both reduced vascular permeability triggered by Ucn but not that by Substance P or histamine. In contrast, the peptide antagonist alpha-helical CRH-(9-41) reduced the effect of all three. The vasodilatory effect of Ucn was largely inhibited by pretreatment with H1 receptor antagonists, suggesting that histamine is the major mediator involved in vitro. Neuropeptide depletion of sensory neurons, treatment with the ganglionic blocker hexamethonium, or in situ skin infiltration with the local anesthetic lidocaine did not affect Ucn-induced vascular permeability, indicating that its in situ effect was not mediated through the peripheral nervous system. These results indicate that Ucn is one of the most potent triggers of rat mast cell degranulation and skin vascular permeability. This effect of Ucn may explain stress-induced disorders, such as atopic dermatitis or psoriasis, and may lead to new forms of treatment.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Hormônio Liberador da Corticotropina/farmacologia , Mastócitos/efeitos dos fármacos , Receptores de Hormônio Liberador da Corticotropina/efeitos dos fármacos , Pele/efeitos dos fármacos , Animais , Degranulação Celular , Azul Evans , Histamina/farmacologia , Masculino , Mastócitos/metabolismo , Mastócitos/patologia , Camundongos , Ratos , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Pele/metabolismo , Pele/patologia , Urocortinas
13.
Endocrinology ; 139(1): 403-13, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9421440

RESUMO

Mast cells are involved in atopic disorders, often exacerbated by stress, and are located perivascularly close to sympathetic and sensory nerve endings. Mast cells are activated by electrical nerve stimulation and millimolar concentrations of neuropeptides, such as substance P (SP). Moreover, acute psychological stress induces CRH-dependent mast cell degranulation. Intradermal administration of rat/human CRH (0.1-10 microM) in the rat induced mast cell degranulation and increased capillary permeability in a dose-dependent fashion. The effect of CRH on Evans blue extravasation was stronger than equimolar concentrations of the mast cell secretagogue compound 48/80 or SP. The free acid analog of CRH, which does not interact with its receptors (CRHR), had no biological activity. Moreover, systemic administration of antalarmin, a nonpeptide CRHR1 antagonist, prevented vascular permeability only by CRH and not by compound 48/80 or SP. CRHR1 was also identified in cultured leukemic human mast cells using RT-PCR. The stimulatory effect of CRH, like that of compound 48/80 on skin vasodilation, could not be elicited in the mast cell deficient W/Wv mice but was present in their +/+ controls, as well as in C57BL/6J mice; histamine could still induce vasodilation in the W/Wv mice. Treatment of rats neonatally with capsaicin had no effect on either Evans blue extravasation or mast cell degranulation, indicating that the effect of exogenous CRH in the skin was not secondary to or dependent on the release of neuropeptides from sensory nerve endings. The effect of CRH on Evans blue extravasation and mast cell degranulation was inhibited by the mast cell stabilizer disodium cromoglycate (cromolyn), but not by the antisecretory molecule somatostatin. To investigate which vasodilatory molecules might be involved in the increase in vascular permeability, the CRH injection site was pretreated with the H1-receptor antagonist diphenhydramine, which largely inhibited the CRH effect, suggesting that histamine was involved in the CRH-induced vasodilation. The possibility that nitric oxide might also be involved was tested using pretreatment with a nitric oxide synthase inhibitor that, however, increased the effect of CRH. These findings indicate that CRH activates skin mast cells at least via a CRHR1-dependent mechanism leading to vasodilation and increased vascular permeability. The present results have implications for the pathophysiology and possible therapy of skin disorders, such as atopic dermatitis, eczema, psoriasis, and urticaria, which are exacerbated or precipitated by stress.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Degranulação Celular/efeitos dos fármacos , Hormônio Liberador da Corticotropina/farmacologia , Dermatite/etiologia , Mastócitos/efeitos dos fármacos , Pele/efeitos dos fármacos , Animais , Humanos , Masculino , Mastócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/fisiologia , Ratos , Ratos Sprague-Dawley
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