Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 93
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Indian J Med Res ; 157(2&3): 204-210, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37202939

RESUMEN

Background & objectives: Chest X-ray (CXR) is an important screening tool for pulmonary tuberculosis (TB). Accessibility to CXR facilities in difficult-to-reach and underserved populations is a challenge. This can potentially be overcome by deploying digital X-ray machines that are portable. However, these portable X-ray machines need to be validated before their deployment in the field. Here, we compare the image quality of CXR taken by a newly developed handheld X-ray machine with routinely used reference digital X-ray machine through the conduct of a feasibility study. Methods: A total of 100 participants with suspected pulmonary TB were recruited from the outpatient departments of a medical college and a community health centre in Agra. Each participant underwent CXR twice, once with each machine. Both sets of de-identified images were independently read by two radiologists, who were blinded to the type of X-ray machine used. The primary outcome was agreement between image qualities produced by these two machines. Results: The intra-observer (radiologist) agreements regarding the status of the 15 CXR parameters ranged between 74 per cent and 100 per cent, with an unweighted mean of 87.2 per cent (95% confidence interval: 71.5-100). The median Cohen's kappa values for intra-observer agreement were 0.62 and 0.67 for radiologists 1 and 2, respectively. In addition, on comparison of the overall median score of quality of the image, the handheld machine images had a higher score for image quality. Interpretation & conclusions: The current study shows that a handheld X-ray machine, which is easy to use and can potentially be carried to any area, produces X-ray images with quality that is comparable to digital X-ray machines routinely used in health facilities.


Asunto(s)
Radiografía Torácica , Tuberculosis Pulmonar , Humanos , Radiografía Torácica/métodos , Rayos X , Sensibilidad y Especificidad , Tuberculosis Pulmonar/diagnóstico por imagen
2.
ORL J Otorhinolaryngol Relat Spec ; 84(2): 103-113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34161952

RESUMEN

INTRODUCTION: Oral mucositis is the most common toxicity of chemoradiotherapy treatment of head and neck cancers. The present study was performed to evaluate the effect of a researched turmeric formulation on oral mucositis in patients receiving chemoradiotherapy for oral cancer. METHODS: This randomized double-blinded placebo-controlled trial included 60 patients with oral cancer who had undergone radical surgery. Patients were equally randomized into 3 arms. Bio-enhanced turmeric formulation (BTF) capsules (low dose [1 g/day] or high dose [1.5 g/day]) or placebo was administered daily for 6 weeks with concurrent chemoradiotherapy. Study endpoints included the impact of the treatment on chemoradiotherapy-induced oral mucositis along with dysphagia, oral pain, dermatitis, and weight loss. RESULTS: The incidence of grade 3 toxicity of oral mucositis, oral pain, dysphagia, and dermatitis was significantly lower in patients who received BTF than placebo. Twenty-five and 20% patients in BTF 1 g/day (p = 0.011) and 1.5 g/day (p = 0.004) arms, respectively, developed grade 3 oral mucositis compared to 65% patients in the placebo arm. Thirty-five and 30% patients in BTF 1 g/day (p = 0.027) and 1.5 g/day (p = 0.011) arms, respectively, developed grade 3 oral pain compared to 70% patients in the placebo arm. Twenty-five and 20% patients in BTF 1 g/day (p = 0.025) and 1.5 g/day (p = 0.010) arms, respectively, developed grade 3 dysphagia compared to 60% patients in the placebo arm. Ten and 5% patients in BTF 1 g/day (p = 0.114) and 1.5 g/day (p = 0.037) arms. respectively, developed grade 3 dermatitis compared to 30% patients in the placebo arm. Patients under BTF supplementation experienced significantly less weight loss and greater compliance with treatment than placebo. CONCLUSION: BTF (BCM-95®) can significantly reduce chemoradiotherapy-induced severe oral mucositis, dysphagia, oral pain, and dermatitis in oral cancer patients. TRIAL REGISTRATION: Clinical Trials Registry, India (Registration No. CTRI) (CTRI/2015/12/006413 dated December 4, 2015).


Asunto(s)
Trastornos de Deglución , Dermatitis , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Estomatitis , Quimioradioterapia/efectos adversos , Curcuma , Trastornos de Deglución/complicaciones , Trastornos de Deglución/tratamiento farmacológico , Dermatitis/complicaciones , Dermatitis/tratamiento farmacológico , Método Doble Ciego , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Dolor/complicaciones , Dolor/tratamiento farmacológico , Estomatitis/tratamiento farmacológico , Estomatitis/epidemiología , Estomatitis/etiología , Pérdida de Peso
3.
Parasitol Res ; 120(8): 2969-2971, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34269870

RESUMEN

Here, we report a simple, economic and autoclavable monophasic LGPY medium supplemented with 10% fetal bovine serum (FBS), for routine maintenance of Leishmania donovani promastigotes for laboratory use. In comparison to commercially available M199 and RPMI-1640 media, LGPY has shown approximately seven fold more cell growth. The parasite has been observed to survive in the medium for at least 15 days post-inoculation. The medium also supports long-term sub-passaging of the promastigotes and can also be stored at 4 °C or room temperature for 14 months and 45 days, respectively.


Asunto(s)
Medios de Cultivo , Leishmania donovani , Leishmania donovani/crecimiento & desarrollo
4.
Technol Forecast Soc Change ; 167: 120679, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33642623

RESUMEN

This study investigates the influence of climate variables (pressure, relative humidity, temperature and wind speed) in inducing risk due to COVID 19 at rural, urban and total (rural and urban) population scale in 623 pandemic affected districts of India incorporating the socioeconomic vulnerability factors. We employed nonstationary extreme value analysis to model the different quantiles of cumulative COVID 19 cases in the districts by using climatic factors as covariates. Wind speed was the most dominating climatic factor followed by relative humidity, pressure, and temperature in the evolution of the cases. The results reveal that stationarity, i.e., the COVID 19 cases which are independent of pressure, relative humidity, temperature and wind speed, existed only in 148 (23.7%) out of 623 districts. Whereas, strong nonstationarity, i.e., climate dependence, was detected in the cases of 474 (76.08%) districts. 334 (53.6%), 200 (32.1%) and 336 (53.9%) districts out of 623 districts were at high risk (or above) at rural, urban and total population scales respectively. 19 out of 35 states were observed to be under high (or above) Kerala, Maharashtra, Goa and Delhi being the most risked ones. The study provides high-risk maps of COVID 19 pandemic at the district level and is aimed at supporting the decision-makers to identify climatic and socioeconomic factors in augmenting the risks.

5.
Indian J Public Health ; 65(3): 321-323, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34558501

RESUMEN

There were many challenges faced by both health-care workers and the common population during the COVID-19 pandemic. One such case was witnessed where a migrant worker abandoned his child in a tertiary care hospital, while he was undergoing treatment for acute liver disease and was reported COVID-19 positive. The child was treated for COVID-19 in the dedicated isolation facility of the hospital as per the guidelines. Later, when the child was declared COVID-19 negative and was ready to discharge, treating doctors found it difficult to hand over the child. The timely intervention and extraordinary efforts by the department of hospital administration and child welfare committee reunited the child with his family.


Asunto(s)
COVID-19 , Niño Abandonado , Niño , Humanos , India , Masculino , Pandemias , SARS-CoV-2 , Centros de Atención Terciaria
6.
Bioorg Med Chem Lett ; 30(1): 126759, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31711783

RESUMEN

A series of substituted 8,8-dimethyl-8H-pyrano[2,3-f]chromen-2-ones (chromeno-coumarin hybrids) was synthesized from scopoletin (11) as vasorelaxing agents. The synthesized compounds 21a-f, 22, 23a-e and scopoletin (11) were evaluated for vasorelaxation in endothelium intact rat main mesenteric artery (MMA). Compounds 11, 21a, 21c-f and 22 showed significant vasorelaxation in precontracted MMA within the range of EC50 value 1.58-5.02 µM. These derivatives presented 29.40-70.89 fold increased sensitivity for experimental tissue compared to scopoletin (11), the parent molecule. Among others, 22 was found to be the most active compound which had EC50 1.58 µM with 70.89 fold increased sensitivity. The mechanistic evaluation of 22 showed that it exerted vasorelaxation through Ca2+-activated K+ (BKca) channel and the effect was endothelium-independent.


Asunto(s)
Descubrimiento de Drogas/métodos , Vasodilatación/efectos de los fármacos , Humanos , Relación Estructura-Actividad
7.
Eur J Clin Pharmacol ; 75(1): 21-31, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30264164

RESUMEN

PURPOSE: Increasing resistance towards antibiotics has augmented the use of probiotics for the treatment of diarrhea and associated symptoms. Probiotics are active microorganisms which exert some health benefits when consumed in the right amount. This randomized, double-blind, placebo-controlled clinical trial was conducted on 60 "intention to treat" subjects to evaluate the safety and efficacy of probiotic preparation Lactic Acid Bacillus (LAB containing active ingredient Bacillus coagulans strain LBSC) for the treatment of acute diarrhea with abdominal discomfort. METHODS: The Test-A arm (n = 30) was on B. coagulans LBSC [2 billion/g] and Placebo-B arm (n = 30) was on the carrier. The primary outcomes were the time to last unformed stool (TTLUS), number of unformed stools, change in severity of abdominal pain, time to complete resolution of abdominal discomfort, complete remission of diarrhea, and quality of life (QoL). The secondary outcomes were physical examination and vitals, hematological analysis, and assessment of reported adverse events (AEs) or serious adverse events (SAEs). RESULTS: Trial data showed that the LAB was well-tolerated by participants at the dose provided. The LAB was effective in recovering from acute diarrhea with abdominal pain and discomforts and exhibited improved cluster of QoL. No AEs or SAEs were reported during the trial. CONCLUSIONS: It is evident that the test drug, i.e., LAB (B. coagulans strain LBSC) is safe and effective for improving the pathophysiological conditions related to acute diarrhea and abdominal discomfort evaluated through stage-II clinical trial.


Asunto(s)
Dolor Abdominal/terapia , Bacillus coagulans , Diarrea/terapia , Probióticos/administración & dosificación , Dolor Abdominal/etiología , Adolescente , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Probióticos/efectos adversos , Estudios Prospectivos , Calidad de Vida , Resultado del Tratamiento , Adulto Joven
8.
Environ Monit Assess ; 190(3): 154, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29464403

RESUMEN

Hydrological regimes of most of the Himalayan river catchments are poorly studied due to sparse hydro-meteorological data. Hence, stream runoff assessment becomes difficult for various socio-industrial activities in the Himalaya. Therefore, an attempt is made in this study to assess the stream runoff of Baspa River in Himachal Pradesh, India, by evaluating the contribution from snow-ice melt and rainfall runoff. The total volume of flow was computed for a period of 15 years, from 2000 to 2014, and validated with the long-term field discharge measurements, obtained from Jaipee Hydropower station (31° 32' 35.53″ N, 78° 00' 54.80″ E), at Kuppa barrage in the basin. The observations suggest (1) a good correlation (r2 > 0.80) between the modeled runoff and field discharge measurements, and (2) out of the total runoff, 81.2% are produced by snowmelt, 11.4% by rainfall, and 7.4% from ice melt. The catchment receives ~75% of its total runoff in the ablation period (i.e., from May to September). In addition, an early snowmelt is observed in accumulation season during study period, indicating the significant influence of natural and anthropogenic factors on high-altitude areas.


Asunto(s)
Monitoreo del Ambiente , Cubierta de Hielo , Lluvia , Hidrología , India , Ríos , Estaciones del Año , Nieve , Movimientos del Agua
9.
Cytokine ; 96: 54-58, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28324803

RESUMEN

Visceral leishmaniasis (VL) is a disease that is associated with compromised immunity and drug un-responsiveness as well as with the emergence of drug resistance in Leishmania donovani (Ld). Ld down-modulates cellular immunity by manipulating signaling agents, including a higher expression of the adhesion molecule CD58. The expression of CD58 and CD2 on natural killer (NK) cells facilitates intercellular adhesion and signaling. The influence of drug-resistant Ld on the expression of CD58 and CD2 was addressed in this study. The mean florescence intensity (MFI) of CD58 but not of CD2 was twofold higher on CD56+ cells during VL, but was down-regulated after treatment. In addition, MFI of CD58 on CD56+ cells was further exacerbated in VL subjects who had relapsed after Ambisome or Miltefosine treatment. The same pattern of CD58 expression was also obtained upon stimulation of healthy peripheral blood mononuclear cells with Miltefosine- or Ambisome-resistant Ld. The ratio of CD56+CD58+IFN-γ+/CD56+CD58+IL-10+ cells was reduced by 6.98-fold after stimulation with Ld. Further, an antagonist to CD58 or its counter-receptor CD2 down-regulated CD56+ NK cell recruitment across a polycarbonate trans-membrane at Ld infection sites. This study reports that factors associated with drug resistance in Ld probably promote higher expression of CD58 on CD56+ cells and their migration to the infection site in association with CD2.


Asunto(s)
Anfotericina B/farmacología , Antígenos CD2/genética , Antígenos CD58/genética , Células Asesinas Naturales/inmunología , Leishmania donovani/efectos de los fármacos , Leishmaniasis Visceral/inmunología , Fosforilcolina/análogos & derivados , Antígenos CD2/antagonistas & inhibidores , Antígenos CD2/metabolismo , Antígeno CD56/genética , Resistencia a Medicamentos , Humanos , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/parasitología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/parasitología , Activación de Linfocitos/efectos de los fármacos , Fosforilcolina/farmacología
10.
Physiol Mol Biol Plants ; 23(1): 99-114, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28250587

RESUMEN

Antioxidant enzymes are known to play a significant role in scavenging reactive oxygen species and maintaining cellular homeostasis. Activity of four antioxidant enzymes viz., superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) was examined in the flag leaves of nine Aegilops tauschii and three Triticum dicoccoides accessions along with two bread wheat cultivars under irrigated and rain-fed conditions. These accessions were shortlisted from a larger set on the basis of field performance for a set of morpho-physiological traits. At anthesis, significant differences were observed in enzyme activities in two environments. A 45% elevation in average GR activity was observed under rain-fed conditions. Genotypic variation was evident within each environment as well as in terms of response to stress environment. Aegilops tauschii accession 3769 (86% increase in SOD, 41% in CAT, 72% in APX, 48% in GR activity) and acc. 14096 (37% increase in SOD, 32% CAT, 25% APX, 42% GR) showed up-regulation in the activity of all the four studied antioxidant enzymes. Aegilops tauschii accessions-9809, 14189 and 14113 also seemed to have strong induction mechanism as elevated activity of at least three enzymes was observed in them under rain-fed conditions. T. dicoccoides, on the other hand, maintained active antioxidative machinery under irrigated condition with relatively lower induction under stress. A significant positive correlation (r = 0.760) was identified between change in the activity of CAT and GR under stress. Changes in plant height, spike length and grain weight were recorded under stress and non-stress conditions on the basis of which a cumulative tolerance index was deduced and accessions were ranked for drought tolerance. Overall, Ae. tauschii accession 3769, 14096, 14113 (DD-genome) and T. dicoccoides accession 7054 (AABB-genome) may be used as donors to combine beneficial stress adaptive traits of all the three sub-genomes into a synthetic hexaploid for improving wheat for water stress conditions.

11.
Lepr Rev ; 87(1): 71-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27255060

RESUMEN

BACKGROUND: Chronic planter ulcer, also known as trophic ulcer, shows no tendency towards healing. It is usually seen in sensory deficient foot. The clinical result of a sensory, motor or autonomic loss of a nerve function is frequently the same--ulceration, although the exact cause may vary. The treatment principle involves dressing and avoiding pressure on the ulcerated site called 'offloading' and patient education for prevention. AIM OF THE STUDY: To determine the outcome of non-healing planter ulcers in an anaesthetic foot treated with offloading, total contact casting (TCC), in terms of rate and duration of healing and percentage of ulcers healed based on improvement of Wagner's grading with respect to the clinical profile of the patient. METHOD: Detailed examination of the patients was done, and neuropathic foot confirmed. Surgical debridement of the ulcer was done to take off all the necrotic tissues, periwound callus, and infected material down to viable tissues. Once the ulcer became clean, a total contact cast was applied with a walking iron for ambulation. TCC was renewed every 2 weeks and rate of healing was assessed. RESULT: 80% of the cases healed within 8 weeks, healing defined by complete re-epithelisation of wound. Average duration of healing of an ulcer was 6.73 ±1.92 weeks. LIMITATIONS OF THE STUDY: Small sample size and the lack of control subjects for comparison. CONCLUSION: Offloading with total contact casts is believed to be the gold standard method with better and faster healing rates.


Asunto(s)
Moldes Quirúrgicos , Úlcera del Pie/etiología , Úlcera del Pie/terapia , Lepra/complicaciones , Aparatos Ortopédicos , Adolescente , Adulto , Niño , Preescolar , Femenino , Úlcera del Pie/patología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
12.
World Hosp Health Serv ; 52(2): 13-18, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30716236

RESUMEN

BACKGROUND: Hospital bed utilization is influenced by various factors which can be divided into patient, physician and administration related. These factors should be seen from the eyes of healthcare providers so that any improvement initiative taken by the administration is matched with the health worker's perception which ultimately affect the hospital efficiency and quality of care. AIM AND OBJECTIVE: To ascertain the factors influencing hospital bed utilization from the perspective of healthcare providers. METHODS: This cross sectional study was conducted in an apex tertiary care public institution in northern region of India. All the resident doctors and nurses in the 18 wards of 7 specialties and 7 super specialties were interviewed using a structured validated self-administered questionnaire. RESULTS: A total of 279 participants (117 doctors and 162 nurses) were enrolled in the study. The factors significantly influencing bed utilization with regard to doctors are patients (2.34, 0.36), physician (2.47, 0.32), administrative (2.61, 0.29) and with regard to nurses are patient (1.97, 0.40), physician (1.97, 0.46), administrative (2.39, 0.40). CONCLUSION: Changing healthcare trends in the recent past (innovations in policy decisions, technological advances, business sustainability aspect, quality initiatives etc.), gave an insight to policy makers (administrators) to consider the perception of healthcare providers (human resource) regarding bed utilization as an important component of healthcare delivery system.


Asunto(s)
Eficiencia Organizacional , Capacidad de Camas en Hospitales , Cuerpo Médico de Hospitales/psicología , Aceptación de la Atención de Salud , Mejoramiento de la Calidad , Adulto , Estudios Transversales , Femenino , Encuestas de Atención de la Salud , Conocimientos, Actitudes y Práctica en Salud , Humanos , India , Masculino , Adulto Joven
13.
AIDS Care ; 26(2): 137-41, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24364397

RESUMEN

Under National TB/HIV framework, all TB patients are referred by Revised National Tuberculosis Programme (RNTCP) service providers to Integrated Counseling and Testing Centers (ICTCs) for voluntary counseling and testing (C&T) and ICTC "TB-suspects" are referred to RNTCP facilities for TB diagnosis and treatment. HIV-TB coinfected patients are then referred to Anti Retroviral Treatment (ART) center for initiation of ART between two weeks and two months of initiating TB treatment. During the third phase of National AIDS Control Programme (NACP-III, April 2007-April 2012), 30749/130503 (23.6%) TB/HIV cross-referrals were lost to follow up (LTFU) and there was missed opportunity for 940/1884 (49.9%) HIV-TB coinfected patients for initiation of ART during TB treatment. This motivated Delhi State AIDS Control Society (DSACS) and State TB Cell (STC) to revise existing cross-referral strategy. The new strategy was launched in May 2012, wherein HIV-TB coinfected and HIV-positive "TB-suspects" were referred to nearest ART center for HIV care and investigations of TB at Chest Clinic/Designated Microscopy Centre (DMC) located within the same hospital instead of referral to area RNTCP facility. Outcome of the strategy was evaluated in March 2013. The new HIV-TB cross-referral strategy in Delhi has shown advantage over national strategy: first, improved retention of coinfected clients in HIV care; second, ensured timely initiation of TB-treatment and ART; and third, significantly improved survival of HIV-TB coinfected patients.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Antituberculosos/uso terapéutico , Servicios de Salud Comunitaria/organización & administración , Consejo , Infecciones por VIH/terapia , Derivación y Consulta , Tuberculosis/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Coinfección , Femenino , Programas de Gobierno/organización & administración , Infecciones por VIH/mortalidad , Conocimientos, Actitudes y Práctica en Salud , Política de Salud , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Evaluación de Programas y Proyectos de Salud , Tuberculosis/mortalidad
14.
BMC Public Health ; 14: 325, 2014 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-24708892

RESUMEN

BACKGROUND: This qualitative investigation was conducted to determine the socio-epidemiological factors related to the plague outbreak (2002) in Himachal Pradesh (HP), India. METHODS: The data for socio-epidemiological factors related to the plague outbreak (2002) in HP was obtained from residents through 150 in-depth Interviews (IDI) and 30 Focus Group Discussions (FGD) during six visits (from May 2011 to April 2012) by the research team. Natives, health officials and the nomadic population were interviewed. According to their opinion and viewpoints data was collected and their lifestyle and hunting practices were studied in detail. Tape recorders were used during various FGDs and IDIs. The interviews and FGDs were later transcribed and coded. In-depth analysis of the recorded data was done using an inductive thematic analysis approach. RESULTS: The study reports that the outbreak in 2002 in a few villages of Himachal Pradesh was that of plague and it occurred by the contact of an index case with wild animals after hunting and de-skinning. The first wave of plague transmission which took 16 lives of residents was followed by a second wave of transmission in a ward of a tertiary care hospital where one visitor acquired it from relatives of the index case and succumbed. The life-style practices of residents (hunting behavior, long stay in caves and jungles, overcrowding in houses, poor hygiene and sanitation, belief in 'God' and faith healers for cure of diseases) was optimal for the occurrence and rapid spread of such a communicable disease. The man-rodent contact is intensified due to the practice of hunting in such a rodent-ridden environment. The residents harbor a strong belief that plague occurs due to the wrath of gods. Various un-reported outbreaks of plague were also observed by officials, residents and old folk. The persistence of plague in HP is favoured by its hilly terrain, inaccessible areas, inclement weather (snow) in winters, unhygienic lifestyle, hunting practices of residents, and treatment practices through faith healers. CONCLUSIONS: This study suggests that the lifestyle of the natives of HP and other socio-epidemiological factors played a role in the outbreak of plague in that area.


Asunto(s)
Brotes de Enfermedades , Peste/epidemiología , Animales , Grupos Focales , Humanos , India/epidemiología , Entrevistas como Asunto , Estilo de Vida , Masculino , Peste/etiología , Peste/transmisión , Investigación Cualitativa , Roedores/microbiología , Saneamiento
15.
Pestic Biochem Physiol ; 115: 39-47, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25307464

RESUMEN

Amylase inhibitors serve as attractive candidates of defense mechanisms against insect attack. Therefore, the impediment of Helicoverpa armigera digestion can be the effective way of controlling this pest population. Nitrite was found to be a potent mixed non-competitive competitive inhibitor of partially purified α-amylase of H. armigera gut. This observation impelled us to determine the response of nitrite and nitrate reductase (NR) towards H. armigera infestation in nine pigeonpea genotypes (four moderately resistant, three intermediate and two moderately susceptible). The significant upregulation of NR in moderately resistant genotypes after pod borer infestation suggested NR as one of the factors that determine their resistance status against insect attack. The pod borer attack caused greater reduction of nitrate and significant accumulation of nitrite in moderately resistant genotypes. The activity of nitrite reductase (NiR) was also enhanced more in moderately resistant genotypes than moderately susceptible genotypes on account of H. armigera herbivory. Expression of resistance to H. armigera was further revealed when significant negative association between NR, NiR, nitrite and percent pod damage was observed. This is the first report that suggests nitrite to be a potent inhibitor of H. armigera α-amylase and also the involvement of nitrite and NR in providing resistance against H. armigera herbivory.


Asunto(s)
Cajanus/enzimología , Cajanus/parasitología , Mariposas Nocturnas/fisiología , Nitrato-Reductasa/metabolismo , Nitritos/metabolismo , Proteínas de Plantas/metabolismo , Animales , Cajanus/genética , Conducta Alimentaria , Herbivoria , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/metabolismo , Mariposas Nocturnas/enzimología , Nitrato-Reductasa/genética , Nitrato Reductasas/genética , Nitrato Reductasas/metabolismo , Proteínas de Plantas/genética , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo
16.
Pestic Biochem Physiol ; 116: 83-93, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25454524

RESUMEN

BACKGROUND: α-Amylase is an important digestive enzyme required for the optimal growth and development of insects. Several insect α-amylases had been purified and their physical and chemical properties were characterized. Insect α-amylases of different orders display variability in structure, properties and substrate specificity. Such diverse properties of amylases could be due to different feeding habits and gut environment of insects. KEY POINTS: In this review, structural features and properties of several insect α-amylases were compared. This could be helpful in exploring the diversity in characteristics of α-amylase between the members of the same class (insecta). Properties like pH optima are reflected in enzyme structural features. In plants, α-amylase inhibitors (α-AIs) occur as part of natural defense mechanisms against pests by interfering in their digestion process and thus could also provide access to new pest management strategies. AIs are quite specific in their action; therefore, these could be employed according to their effectiveness against target amylases. Potential of transgenics with α-AIs has also been discussed for insect resistance and controlling infestation. CONCLUSIONS: The differences in structural features of insect α-amylases provided reasons for their efficient functioning at different pH and the specificity towards various substrates. Various proteinaceous and non-proteinaceous inhibitors discussed could be helpful in controlling pest infestation. In depth detailed studies are required on proteinaceous α-AI-α-amylase interaction at different pH's as well as the insect proteinase action on these inhibitors before selecting the α-AI for making transgenics resistant to particular insect.


Asunto(s)
Proteínas de Insectos , Isoenzimas , alfa-Amilasas , Animales , Inhibidores Enzimáticos/farmacología , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Insectos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Isoenzimas/metabolismo , Plantas Modificadas Genéticamente , Especificidad por Sustrato , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/química , alfa-Amilasas/metabolismo
17.
J Environ Biol ; 35(6): 1037-45, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25522503

RESUMEN

Antioxidative compounds were quantified from the leaves of nine black gram (Vigna mungo (L.) Hepper) genotypes over a period of two years, for potential whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleryrodidae) resistance. Oviposition preference, nymphal and adult development were evaluated under screen-house conditions. Biochemical analysis revealed that higher per cent increase in the total phenol and o-dihydroxy phenol contents both at 30 and 50 days after sowing was evident in moderately resistant genotypes NDU 5-7 (49.6 and 50.8%, respectively) and KU 99-20 (47.8 and 50.8%, respectively) under whitefly stress conditions as compared to non-stressed plants. Tannin and flavonol contents in leaves increased to varying degrees (up to 11.1 and 7.1%, respectively) in resistant plants after whitefly infestation, indicating that the changes in tannin and flavonol contents were closely associated with the resistance to whitefly. Correlation studies relating leaf content of black gram antioxidative compounds from different genotypes with whitefly population were also worked out. Total phenols (r = -0.71 & -0.88), o- dihydroxy phenols (r = -0.56 & -0.76), flavonols (r = -0.80 & -0.81) and tannins (r= -0.16 & -0.26) showed significant negative correlation with whitefly population (nymphs and adults) suggesting that enhanced level of these biochemicals may contribute to bioprotection of black gram plants against B. tabaci infestation. Comparatively higher level of resistance in genotype NDU 5-7 and KU 99-20 can serve as base for genetic improvement of black gram, focusing on the development of resistant varieties to B. tabaci.


Asunto(s)
Antioxidantes/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Animales , Conducta Alimentaria/fisiología , Genotipo , Hemípteros/fisiología , Hojas de la Planta/enzimología
18.
Sci Rep ; 14(1): 3020, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321045

RESUMEN

Over the past century, the average surface temperature and recurrent heatwaves have been steadily rising, especially during the summer season, which is affecting the yield potential of most food crops. Hence, diversification in cropping systems with suitable fertilizer management is an urgent need to ensure high yield potential during the summer season. Since intercropping has emerged as an important strategy to increase food production, the present study comprises five intercropping systems in the main plot (sole cowpea, sole baby corn, cowpea + baby corn in 2:1, 3:1, and 4:1 row ratio), three levels of fertilizer viz. 100 (N20 P40), 125 (N25 P50), and 150% (N30 P60) recommended dose of fertilizer (RDF) in the subplot, along with two stress-mitigating chemicals (0.5% CaCl2 and 1% KNO3) in the sub-sub plots. A split-split plot system with four replications was established to carry out the field experiment. The effect of intercropping, fertilizer levels, and stress-mitigating chemicals on crop growth rate (CGR), relative growth rate (RGR), plant temperature, relative water content (RWC) and chlorophyll content of cowpea and baby corn, as well as cowpea equivalent yield (CEY), was investigated during the summer seasons of 2019 and 2020. The experiment was conducted at Agriculture University, Kota (Rajasthan), India. Results showed that CGR, RGR, RWC and chlorophyll content of both crops and CEY were maximum under intercropping of cowpea and baby corn in a 2:1 row ratio compared to other intercropping systems. However, the plant temperature of both crops was significantly lower under this system. CEY, CGR, RGR, and chlorophyll content were considerably greater in the subplots with a fertilizer application of 150% RDF compared to lower levels of fertilizer (100 and 125% RDF). Our findings further show that foliar application of CaCl2 0.5% at the flowering and pod-developing stages of cowpea dramatically boosted CEY, CGR, RGR, RWC, and chlorophyll content of both crops and lowered the plant temperature.


Asunto(s)
Vigna , Humanos , Estaciones del Año , Zea mays , Fertilizantes , Cloruro de Calcio , India , Agricultura/métodos , Productos Agrícolas , Fertilidad , Clorofila
19.
J Med Chem ; 67(4): 2369-2378, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38335279

RESUMEN

There remains a need to develop novel SARS-CoV-2 therapeutic options that improve upon existing therapies by an increased robustness of response, fewer safety liabilities, and global-ready accessibility. Functionally critical viral main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target due to its homology within the coronaviral family, and lack thereof toward human proteases. In this disclosure, we outline the advent of a novel SARS-CoV-2 3CLpro inhibitor, CMX990, bearing an unprecedented trifluoromethoxymethyl ketone warhead. Compared with the marketed drug nirmatrelvir (combination with ritonavir = Paxlovid), CMX990 has distinctly differentiated potency (∼5× more potent in primary cells) and human in vitro clearance (>4× better microsomal clearance and >10× better hepatocyte clearance), with good in vitro-to-in vivo correlation. Based on its compelling preclinical profile and projected once or twice a day dosing supporting unboosted oral therapy in humans, CMX990 advanced to a Phase 1 clinical trial as an oral drug candidate for SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Diferenciación Celular , Revelación , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Antivirales/farmacología
20.
Indian J Exp Biol ; 51(9): 746-57, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24377135

RESUMEN

Two wheat cultivars, C306 and PBW343 contrasting in drought tolerance were compared for their antioxidant response and Lea genes' expression under salt stress (SS) and combined stress (CS) of salt stress plus water stress during seedlings growth. The drought susceptible cultivar (PBW343) behaved different towards SS/CS than towards WS. It accumulated more dry masses in shoots, more ascorbate, had higher ascorbate to dehydroascorbate ratio, lesser dehydroascorbate, lesser malondialdehyde (MDA), more proline and higher antioxidant enzymes under SS than under WS. CS increased dry masses, ascorbate, ascorbate to dehydroascorbate ratio, antioxidant enzymes and decreased dehydroascorbate and MDA contents from levels under WS. The drought tolerant cultivar (C306) though showed higher levels of ascorbate, ascorbate to dehydroascorbate ratio, lower levels of dehydroascorbate, showed lesser dry biomasses in shoots, higher MDA and lesser ascorbate peroxidase and catalase activities under SS than under WS and these features were improved on combining WS with SS. All lea genes were induced under all stresses in both cultivars except Wrab17 in C306 only, was not induced under any stress. Eight Lea genes out of ten were induced higher under WS than SS in C306 but induced same in PBW343. Wdhn13 gene was higher salt-responsive than other lea genes in both cultivars.


Asunto(s)
Adaptación Fisiológica , Antioxidantes/metabolismo , Sequías , Expresión Génica , Genes de Plantas , Cloruro de Sodio , Triticum/fisiología , Catalasa/metabolismo , Glutatión Reductasa/metabolismo , Malondialdehído/metabolismo , Triticum/crecimiento & desarrollo , Triticum/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA