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1.
Physiol Mol Biol Plants ; 30(3): 417-433, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38633277

RESUMO

Allelopathy is a natural phenomenon of competing and interfering with other plants or microbial growth by synthesizing and releasing the bioactive compounds of plant or microbial origin known as allelochemicals. This is a sub-discipline of chemical ecology concerned with the effects of bioactive compounds produced by plants or microorganisms on the growth, development and distribution of other plants and microorganisms in natural communities or agricultural systems. Allelochemicals have a direct or indirect harmful effect on one plant by others, especially on the development, survivability, growth, and reproduction of species through the production of chemical inhibitors released into the environment. Cultivation systems that take advantage of allelopathic plants' stimulatory/inhibitory effects on plant growth and development while avoiding allelopathic autotoxicity is critical for long-term agricultural development. Allelopathy is one element that defines plant relationships and is involved in weed management, crop protection, and microbial contact. Besides, the allelopathic phenomenon has also been reported in the forest ecosystem; however, its presence depends on the forest type and the surrounding environment. In the present article, major aspects addressed are (1) literature review on the impacts of allelopathy in agroecosystems and underpinning the research gaps, (2) chemical, physiological, and ecological mechanisms of allelopathy, (3) genetic manipulations, plant defense, economic benefits, fate, prospects and challenges of allelopathy. The literature search and consolidation efforts in this article shall pave the way for future research on the potential application of allelopathic interactions across various ecosystems.

2.
Int J Neurosci ; 133(6): 642-647, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34275423

RESUMO

Rosette-forming glioneuronal tumor (RGNT) of the 4th ventricle is a newly described WHO grade I brain tumor included in recent WHO classification of CNS tumors. It is a biphasic tumor thought to originate from pluripotent progenitor cells of subependymal plate. Intra-operative diagnosis plays an important role, as complete surgical excision is the treatment of choice. We are reporting a case of RGNT in a 19 years-old young male emphasizing the intra-operative pathological pointers and their role in accurate diagnosis for the suitable surgical intervention.


Assuntos
Neoplasias Encefálicas , Neoplasias do Ventrículo Cerebral , Masculino , Humanos , Adulto Jovem , Adulto , Neoplasias do Ventrículo Cerebral/diagnóstico por imagem , Neoplasias do Ventrículo Cerebral/cirurgia , Quarto Ventrículo/diagnóstico por imagem , Quarto Ventrículo/cirurgia , Quarto Ventrículo/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Técnicas Citológicas , Formação de Roseta
4.
Br J Neurosurg ; 37(1): 35-40, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33349075

RESUMO

BACKGROUND: Gliomas are the most aggressive form of brain tumors responsible for the majority of brain cancer related deaths. Interleukin (IL)-6, 10 and tumor necrosis factor (TNF)- α are tumor specific proteins that are expressed in gliomas. This study aims to estimate the pre- and postoperative levels of serum markers of these cytokines to evaluate any bearing with its grade and volume. METHODS: Prospective analysis of 80 patients of newly-diagnosed gliomas of any grade was carried out. Pre- and postoperative blood samples day one, one month and at 3rd month of surgery was taken and levels of IL-6, 10 and TNF- α measured and matched with 20 healthy controls. RESULTS: Of the 80 patients, 3 patients had pilocytic astrocytoma, 4 had ganglioglioma, 9 had oligodendroglioma, 17 had diffuse astrocytoma, 5 had anaplastic astrocytoma while 43 had glioblastoma. Preoperative levels of IL-6 and TNF- α was found to be markedly raised in high grade gliomas. Positive correlation was seen between IL-6 with the grade of tumor and high-grade tumors were seen to be more significantly correlated with IL-6. However, preoperative IL-10 in both low and high grade of gliomas did not show any correlation with the volume and grade of tumor. CONCLUSION: High level of IL-6 and TNF-α in peripheral blood in patients of high-grade gliomas provides clue to the invasiveness of the disease which can be useful for understanding the premorbid development of tumor and perhaps extrapolating to ongoing tumor response to treatment.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Humanos , Estudos Prospectivos , Citocinas , Interleucina-6 , Astrocitoma/cirurgia , Astrocitoma/patologia , Glioma/cirurgia , Glioma/patologia , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Fator de Necrose Tumoral alfa
5.
Br J Neurosurg ; 36(1): 94-97, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29745260

RESUMO

Rhinosporidiosis is a chronic fungal inflammatory disease prevalent in India and Sri Lanka. Its manifestations are mostly nasal and extranasal lesions are relatively rare. Occasional atypical presentations of this disease lead to diagnostic dilemma. Herein we report on a case of nasopharyngeal rhinosporidiosis having extensive involvement of paranasal sinuses along with intracranial extension which mimicked radiologically as juvenile nasopharyngeal angiofibroma. To our knowledge, this is the first reported case of rhinosporidiosis having intracranial extension. We discuss the pathology, treatment and briefly review the literature of this rare disease.


Assuntos
Angiofibroma , Neoplasias de Cabeça e Pescoço , Rinosporidiose , Angiofibroma/diagnóstico por imagem , Angiofibroma/cirurgia , Animais , Humanos , Nariz , Rinosporidiose/diagnóstico , Rinosporidiose/patologia , Rinosporidiose/cirurgia , Rhinosporidium
6.
Environ Monit Assess ; 194(2): 50, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34984556

RESUMO

Wetlands are emitters of greenhouse gases. However, many of the wetlands remain understudied (like temperate, boreal, and high-altitude wetlands), which constrains the global budgets. Himalayan foothill is one such data-deficient area. The present study reported (for the first time) the greenhouse gas fluxes (CO2, CH4, N2O, and H2O vapor) from the soils of the Nakraunda wetland of Uttarakhand in India during the post-monsoon season (October 2020 to January 2021). The sampling points covered six different types of soil within the wetlands. CO2, CH4, N2O, and H2O vapor emissions ranged from 82.89 to 1052.13 mg m-2 h-1, 0.56 to 2.25 mg m-2 h-1, 0.18 to 0.40 mg m-2 h-1, and 557.96 to 29,397.18 mg m-2 h-1, respectively, during the study period. Except for CO2, the other three greenhouse gas effluxes did not show any spatial variability. Soils close to "swamp proper" emitted substantially higher CO2 than the vegetated soils. Soil temperature exhibited exponential relationships with all the greenhouse gas fluxes, except for H2O vapor. The Q10 values for CO2, CH4, and N2O varied from 3.42 to 4.90, 1.66 to 2.20, and 1.20 to 1.30, respectively. Soil moisture showed positive relationships with all the greenhouse gas fluxes, except for N2O. The fluxes observed from Nakraunda were in parity with global observations. However, this study showed that wetlands experiencing lower temperature regime are also capable of emitting a substantial amount of greenhouse gases and thus, requires more study. Considering the seasonality of greenhouse gas fluxes should improve global wetland emission budgets.


Assuntos
Dióxido de Carbono , Áreas Alagadas , Dióxido de Carbono/análise , Monitoramento Ambiental , Metano/análise , Óxido Nitroso/análise , Solo
8.
Environ Monit Assess ; 191(Suppl 3): 794, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989314

RESUMO

Biological invasion is probably one of the most serious threats to biodiversity after climate change. Landscape distinguished by the heterogeneity of structure, forms, human interferences, and environmental settings plays an important role in the establishment and spread of invasive species. We investigated the effect of the spatial heterogeneity for a selected landscape upon the invasion process through a case study of Hyptis (Hyptis suaveolens) in the Indian Western Himalayan region. The selected study site constitutes a heterogeneous landscape of 32,300 ha in the state of Uttarakhand, placed at the lower elevation of the Indian Himalaya. The landscape has varying levels and patterns of Hyptis invasion. We quantified the spatial heterogeneity in terms of elevation; distance from the canal, river, road, and settlement; and 18 landscape metrics (at the patch and land use class level) to investigate their influence on the invasion; for this purpose, a logistic regression model was developed. The invasion of Hyptis was found to be governed by spatial heterogeneity. The highest probability of invasion was found in the areas adjacent to rivers and roads. The analysis at patch level revealed that the invasion is largely governed by the perimeter-area ratio of patches and is positively correlated. This suggests for greater invasion chances in smaller patches as compared with larger ones. The analysis for the land use class metrics indicated a higher influence of edge density expressed as total edge length of patches per unit area, followed by patch density expresses as a total number of patches per unit area. Hence, the landscapes with larger edges and more number of patches are supposed to be more prone to invasion risks. The results of the study can be used by forest managers in designing a landscape-level system to control invasion.


Assuntos
Ecossistema , Hyptis , Espécies Introduzidas , Biodiversidade , Monitoramento Ambiental , Plantas
9.
Crit Rev Biotechnol ; 37(4): 476-491, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27291252

RESUMO

Proteases are ubiquitous enzymes that occur in various biological systems ranging from microorganisms to higher organisms. Microbial proteases are largely utilized in various established industrial processes. Despite their numerous industrial applications, they are not efficient in hydrolysis of recalcitrant, protein-rich keratinous wastes which result in environmental pollution and health hazards. This paved the way for the search of keratinolytic microorganisms having the ability to hydrolyze "hard to degrade" keratinous wastes. This new class of proteases is known as "keratinases". Due to their specificity, keratinases have an advantage over normal proteases and have replaced them in many industrial applications, such as nematicidal agents, nitrogenous fertilizer production from keratinous waste, animal feed and biofuel production. Keratinases have also replaced the normal proteases in the leather industry and detergent additive application due to their better performance. They have also been proved efficient in prion protein degradation. Above all, one of the major hurdles of enzyme industrial applications (cost effective production) can be achieved by using keratinous waste biomass, such as chicken feathers and hairs as fermentation substrate. Use of these low cost waste materials serves dual purposes: to reduce the fermentation cost for enzyme production as well as reducing the environmental waste load. The advent of keratinases has given new direction for waste management with industrial applications giving rise to green technology for sustainable development.


Assuntos
Bactérias/enzimologia , Queratinas/química , Peptídeo Hidrolases/química , Gerenciamento de Resíduos , Biodegradação Ambiental , Biotecnologia/métodos , Biotecnologia/tendências , Poluição Ambiental , Fermentação , Hidrólise , Peptídeo Hidrolases/genética , Resíduos
10.
Neurol India ; 64(4): 671-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27381112

RESUMO

INTRODUCTION: Infection associated with a ventriculoperitoneal shunt is a severe complication with a high morbidity and substantial mortality. There are no guidelines to choose antibiotics in case of shunt infection. Most surgeons use antibiotics of their choice whereas limited centres follow their own antibiotic policy. An alarming increase in antibiotic resistance has led to rising morbidity and mortality. MATERIALS AND METHODS: This was a retrospective analysis of patients who underwent ventriculoperitoneal shunt surgery between January 2010 and December 2015 at our institution. Shunt tubes and cerebrospinal fluid were sent for culture and sensitivity in patients who were suspected clinically of having shunt tube infections. The processing of the samples was done by standard techniques, and the identification of the organism along with its sensitivity pattern was performed using Vitek 2 system. RESULTS: A total of 1186 ventriculoperitoneal shunt surgeries were performed during this period at our institute in patients of all age groups. There were 757 (63.8%) male and 429 (36.2%) female patients. A total of 156 samples of patients were sent for culture and sensitivity during this period, out of which 79 (50.6%) samples had growth of an organism either in the cerebrospinal fluid [36 (23.1%)], shunt tubing [16 (10.2%)], or in both [27 (17.3%)]. The most common organisms grown in the cultures were Staphylococcus aureus [65 (82.3%)] or coagulase-negative Staphylococcus [22 (25.3%)] in the Gram-positive group and Escherichia coli [17 (21.5%)] in the Gram-negative group. Over the last 6 years, the sensitivity pattern of both Gram-negative and Gram-positive bacteria has shown alarming decreasing sensitivity for various commonly used antibiotics. CONCLUSION: Ventriculoperitoneal shunt infection has become an important concern in cases of hydrocephalus. Due to the development of a high proportion of antibiotic resistance, we recommend an empirical therapy of antibiotic therapy for prophylaxis and suspected infection in ventriculoperitoneal shunt surgery.


Assuntos
Antibacterianos/uso terapêutico , Infecções/tratamento farmacológico , Procedimentos Neurocirúrgicos , Derivação Ventriculoperitoneal/efeitos adversos , Bactérias/isolamento & purificação , Feminino , Humanos , Infecções/etiologia , Masculino , Padrões de Prática Médica
11.
J Craniofac Surg ; 26(4): 1313-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080183

RESUMO

The desired features of a cranioplast include providing an acceptable contour, continuity with the remaining skull (marginal adaptation), improvising the aesthetic outcome, providing a strengthened prosthesis to avoid fracture in case of repeat trauma, and protecting the remaining neurological structures. Combining digital and manual techniques to fabricate a hybrid polymethylmethacrylate cranioplast during the rehabilitation of a pediatric patient with cranial defect has been described. Utilization of digital techniques (rapid prototyping to obtain skull analog) and manual (hand) sculpting of the prosthesis strengthened with glass fiber enabled the authors to fabricate a hybrid cranioplast. Satisfactory outcome was achieved.


Assuntos
Anormalidades Craniofaciais/cirurgia , Metilmetacrilato , Procedimentos de Cirurgia Plástica/métodos , Próteses e Implantes , Crânio/cirurgia , Criança , Desenho Assistido por Computador , Anormalidades Craniofaciais/diagnóstico por imagem , Humanos , Masculino , Desenho de Prótese , Radiografia , Crânio/diagnóstico por imagem
12.
Appl Opt ; 53(28): 6472-81, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25322235

RESUMO

We propose a method for fully phase image encryption based on double random-structured phase mask encoding in the gyrator transform (GT) domain. The security of the system is strengthened by parameters used in the construction of a structured phase mask (SPM) based on a devil's vortex Fresnel lens (DVFL). The input image is recovered using the correct parameters of the SPMs, transform orders of the GT, and conjugate of the random phase masks. The use of a DVFL-based SPM enhances security by increasing the key space for encryption, and also overcomes the problem of axis alignment associated with an optical setup. The proposed scheme can also be implemented optically. The computed values of mean squared error between the retrieved and the original image show the efficacy of the proposed scheme. We have also investigated the scheme's sensitivity to the encryption parameters, and robustness against occlusion and multiplicative Gaussian noise attacks.

13.
Plant Physiol Biochem ; 210: 108610, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615447

RESUMO

In the face of the formidable environmental challenges precipitated by the ongoing climate change, Plant Growth-Promoting Bacteria (PGPB) are gaining widespread acknowledgement for their potential as biofertilizers, biocontrol agents, and microbial inoculants. However, a knowledge gap pertains to the ability of PGPB to improve stress tolerance in forestry species via cross-inoculation. To address this gap, the current investigation centres on PGPBs, namely, Acinetobacter johnsonii, Cronobacter muytjensii, and Priestia endophytica, selected from the phyllosphere of robust and healthy plants thriving in the face of stress-inducing conditions. These strains were selected based on their demonstrated adaptability to saline, arid, and nitrogen-deficient environments. The utilization of PGPB treatment resulted in an improvement of stomatal conductance (gs) and transpiration rate (E) in poplar plants exposed to both salt and drought stress. It also induced an increase in essential biochemical components such as proline (PRO), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). These reactions were accompanied by a decrease in leaf malonaldehyde (MDA) content and electrolyte leakage (EL). Furthermore, the PGPB treatment demonstrated a notable enhancement in nutrient absorption, particularly nitrogen and carbon, achieved through the solubilization of nutrients. The estimation of canopy temperature via thermal imaging proved to be an efficient method for distinguishing stress reactions in poplar than conventional temperature recording techniques. In summation, the utilization of PGPB especially Cronobacter muytjensii in this study, yielded profound improvements in the stress tolerance of poplar plants, manifesting in reduced membrane lipid peroxidation, enhanced photosynthesis, and bolstered antioxidant capacity within the leaves.


Assuntos
Populus , Estresse Fisiológico , Populus/microbiologia , Populus/fisiologia , Endófitos/fisiologia , Folhas de Planta/metabolismo , Secas , Prolina/metabolismo , Adaptação Fisiológica , Acinetobacter/fisiologia
16.
Environ Sci Pollut Res Int ; 30(57): 121224-121235, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37950783

RESUMO

Climate change profoundly impacts ecosystems' function and composition, changing living organisms' habitats. The Indian Himalayan ecosystem (IHE) is particularly susceptible and vulnerable to the effects of climate change. However, our understanding of how climate change affects the habitats of range-restricted and vulnerable avifauna in the IHE still needs to be improved. Hence, we employed ensemble species distribution modelling to examine the potential habitat shift of the cheer pheasant (Catreus wallichii) under climate change scenarios (representative concentration pathways, RCPs) i.e. RCP 4.5, RCP 6.0 and RCP 8.5) by 2050 and 2070. The study revealed a noticeable expansion of climatically suitable habitats, indicating a shift towards higher altitudes that would become more favourable and suitable under future climates. The model predicted an area of very highly suitable habitat (1247.4 km2), followed by highly suitable (2747.9 km2), moderately suitable (4002.3 km2), low suitable (4952.2 km2) and rarely suitable (4236 km2) in the current scenario. The projection of larger areas was falling into the "no change", followed by the "high suitable" and "low suitable" classes, for both the years 2050 and 2070 across all the RCPs. Furthermore, the projections indicated a consistent trend of increasing suitability for the cheer pheasant at higher elevations and a decline at lower elevations across RCPs for 2050 and 2070. Moreover, the mean diurnal temperature range was identified as the crucial driving factor, followed by isothermally and precipitation, influencing the species' shift towards suitable habitats at higher altitudes. The study can aid policymakers in developing effective conservation strategies to protect Himalayan range-restricted bird species in the face of climate change.


Assuntos
Mudança Climática , Ecossistema , Animais , Codorniz
17.
Surg Neurol Int ; 14: 327, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810289

RESUMO

Background: Colloid cysts, common benign lesions of the third ventricle, have rarely been reported in uncommon extraventricular locations such as the pituitary fossa. Even in the sellar region, it is usually seen between the anterior and posterior pituitary lobes (pars intermedia). Case Description: Here, we report a case of a female patient, who was incidentally diagnosed with a sellar colloid cyst, while being evaluated for nonspecific holocranial headache. On imaging, there was a lesion located in the anterior sellar region, compressing the whole pituitary gland posteriorly (first reported case to the best of our knowledge), that was found to be a colloid cyst intraoperatively during microsurgical excision through transnasal transsphenoidal route. Conclusion: This rare entity should be kept in mind while considering lesions of the pituitary region, as evident by typical radiological features, in spite of being located in a less likely site.

18.
Br J Neurosurg ; 26(5): 747-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22591406

RESUMO

OBJECTIVES: Most of our understanding of ventriculoperitoneal (VP) shunt blockage (ventricular end) is based on in vitro studies of blocked VP shunts. Not much information is available regarding the in vivo changes that occur in the tube and in the surrounding ventricle. The primary aim of our study was to observe and analyse these changes, directly, through the endoscope, in patients with blocked shunts undergoing an endoscopic third ventriculostomy (ETV). Based on these findings, we have also suggested criteria for safe removal of the VP shunt tube following ETV. MATERIAL AND METHODS: ETV was performed with standard technique in patients with blocked VP shunt. The ventricular end of the shunt tube was inspected through the endoscope, for changes in ventricle linings as well as in the shunt tube. These changes were correlated with the age of the patient, etiology of HC, type or make of the shunt tube, duration of shunt placement to ETV and the CSF findings. RESULTS: Fifty-three patients of blocked VP shunt underwent ETV from July 2006 to April 2010. Thirty patients had Chhabra (CH) V P Shunt (Surgiwear, India) and 23 had ceredrain (CD) shunt (Hindustan Latex, India). The age of the patients ranged from 2 months to 60 years (mean--13.33 years.). Various causes of hydrocephalus (HC) included congenital hydrocephalus (aqueductal stenosis) in 18 patients, post-meningitis hydrocephalus (PMH) in 32 cases, neuro-cysticercosis (NCC) in 2 patients and intraventricular haemorrhagic (IVH) in 1 patient. Clinical and radiological improvement occurred in 33 (62.21%), and 24 (45%) patients, respectively. Freedom from shunt was attained in 20 (38%) patients. The changes around the shunt tube were seen in 41 (77%). Hyperaemia and neovascularised ependyma was seen in 20 (37%) and 15 (28%) patients. Encasement of the tube was seen in 41%. Ependymal growth and neovascularised shunt tubes were noticed in 15% each. Choroid plexus blocking the tube was seen in only four cases (7%). VP shunt was revised in 14 patients (26.4%). Patient with infective etiology had more changes (p < 0.005). Age, CSF findings and make of shunt tube had no relation with endoscopic observations (p< 0.02). CONCLUSIONS: ETV has a role in shunt failures. It can offer patient a chance of shunt free life. Endoscopic observation of shunt tube and ventricle can unfold several interesting in vivo findings pertaining to shunt obstruction. Shunt should only be removed if there are no adhesions and neovascularisation.


Assuntos
Falha de Equipamento , Neuroendoscopia/métodos , Derivação Ventriculoperitoneal/instrumentação , Adolescente , Adulto , Hemorragia Cerebral/complicações , Criança , Pré-Escolar , Remoção de Dispositivo/métodos , Feminino , Humanos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Lactente , Masculino , Pessoa de Meia-Idade , Neurocisticercose/complicações , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
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