Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Physiol Plant ; 176(3): e14399, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38894599

RESUMEN

Salicylic acid (SA) is an important phytohormone, well-known for its regulatory role in shaping plant immune responses. In recent years, significant progress has been made in unravelling the molecular mechanisms underlying SA biosynthesis, perception, and downstream signalling cascades. Through the concerted efforts employing genetic, biochemical, and omics approaches, our understanding of SA-mediated defence responses has undergone remarkable expansion. In general, following SA biosynthesis through Avr effectors of the pathogens, newly synthesized SA undergoes various biochemical changes to achieve its active/inactive forms (e.g. methyl salicylate). The activated SA subsequently triggers signalling pathways associated with the perception of pathogen-derived signals, expression of defence genes, and induction of systemic acquired resistance (SAR) to tailor the intricate regulatory networks that coordinate plant immune responses. Nonetheless, the mechanistic understanding of SA-mediated plant immune regulation is currently limited because of its crosstalk with other signalling networks, which makes understanding this hormone signalling more challenging. This comprehensive review aims to provide an integrated overview of SA-mediated plant immunity, deriving current knowledge from diverse research outcomes. Through the integration of case studies, experimental evidence, and emerging trends, this review offers insights into the regulatory mechanisms governing SA-mediated immunity and signalling. Additionally, this review discusses the potential applications of SA-mediated defence strategies in crop improvement, disease management, and sustainable agricultural practices.


Asunto(s)
Inmunidad de la Planta , Ácido Salicílico , Transducción de Señal , Ácido Salicílico/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Plantas/inmunología , Plantas/metabolismo , Plantas/genética
2.
Brain Commun ; 6(3): fcae139, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715715

RESUMEN

Delirium, memory loss, attention deficit and fatigue are frequently reported by COVID survivors, yet the neurological pathways underlying these symptoms are not well understood. To study the possible mechanisms for these long-term sequelae after COVID-19 recovery, we investigated the microstructural properties of white matter in Indian cohorts of COVID-recovered patients and healthy controls. For the cross-sectional study presented here, we recruited 44 COVID-recovered patients and 29 healthy controls in New Delhi, India. Using deterministic whole-brain tractography on the acquired diffusion MRI scans, we traced 20 white matter tracts and compared fractional anisotropy, axial, mean and radial diffusivity between the cohorts. Our results revealed statistically significant differences (PFWE < 0.01) in the uncinate fasciculus, cingulum cingulate, cingulum hippocampus and arcuate fasciculus in COVID survivors, suggesting the presence of microstructural abnormalities. Additionally, in a subsequent subgroup analysis based on infection severity (healthy control, non-hospitalized patients and hospitalized patients), we observed a correlation between tract diffusion measures and COVID-19 infection severity. Although there were significant differences between healthy controls and infected groups, we found no significant differences between hospitalized and non-hospitalized COVID patients. Notably, the identified tracts are part of the limbic system and orbitofrontal cortex, indicating microstructural differences in neural circuits associated with memory and emotion. The observed white matter alterations in the limbic system resonate strongly with the functional deficits reported in Long COVID. Overall, our study provides additional evidence that damage to the limbic system could be a neuroimaging signature of Long COVID. The findings identify targets for follow-up studies investigating the long-term physiological and psychological impact of COVID-19.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38082780

RESUMEN

Damage to the inferior frontal gyrus (Broca's area) can cause agrammatic aphasia wherein patients, although able to comprehend, lack the ability to form complete sentences. This inability leads to communication gaps which cause difficulties in their daily lives. The usage of assistive devices can help in mitigating these issues and enable the patients to communicate effectively. However, due to lack of large scale studies of linguistic deficits in aphasia, research on such assistive technology is relatively limited. In this work, we present two contributions that aim to re-initiate research and development in this field. Firstly, we propose a model that uses linguistic features from small scale studies on aphasia patients and generates large scale datasets of synthetic aphasic utterances from grammatically correct datasets. We show that the mean length of utterance, the noun/verb ratio, and the simple/complex sentence ratio of our synthetic datasets correspond to the reported features of aphasic speech. Further, we demonstrate how the synthetic datasets may be utilized to develop assistive devices for aphasia patients. The pre-trained T5 transformer is fine-tuned using the generated dataset to suggest 5 corrected sentences given an aphasic utterance as input. We evaluate the efficacy of the T5 model using the BLEU and cosine semantic similarity scores. Affirming results with BLEU score of 0.827/1.00 and semantic similarity of 0.904/1.00 were obtained. These results provide a strong foundation for the concept that a synthetic dataset based on small scale studies on aphasia can be used to develop effective assistive technology.Clinical relevance- We demonstrate the utilization of Natural Language Processing (NLP) for developing assistive technology for Aphasia patients. While disorders like Broca's aphasia offer a small sample size of patients and data, synthetic linguistic models like ours offer extensive scope for developing assistive technology and rehabilitation monitoring.


Asunto(s)
Afasia de Broca , Procesamiento de Lenguaje Natural , Humanos , Lingüística , Lenguaje , Semántica
4.
Artículo en Inglés | MEDLINE | ID: mdl-38082828

RESUMEN

Even after recovery from the COVID-19 infection, there have been a multitude of cases reporting post-COVID neurological symptoms including memory loss, brain fog, and attention deficit. Many studies have observed localized microstructural damages in the white matter regions of COVID survivors, indicating potential damage to the axonal pathways in the brain. Therefore, in this study, we have investigated the global impact of localized damage to white matter tracts using graph theoretical analysis of the structural connectome of 45 COVID-recovered subjects and 30 Healthy Controls (HCs). We have implemented Diffusion Tensor Imaging based reconstruction followed by deterministic tractography to extract structural connections among different regions of the brain. Interpreting this structural connectivity as weighted undirected graphs, we have used graph theoretical measures like global efficiency, characteristic path length (CPL), clustering coefficient (CC), modularity, Fiedler value, and assortativity coefficient to quantify the global integration, segregation, and robustness of the brain networks. We statistically compare the cohorts based on these graph measures by employing permutation testing for 100,000 permutations. Post multiple comparisons error correction, we find that the COVID-recovered cohort shows a reduction in global efficiency and CC while they exhibit higher modularity and CPL. This disruption of the balance between global integration and segregation indicates the loss of small-world property in COVID survivors' connectomes which has been linked with other disorders such as cognitive impairment and Alzheimer's. Overall, our study sheds light on the alterations in structural connectivity and its role in post-COVID symptoms.


Asunto(s)
COVID-19 , Conectoma , Sustancia Blanca , Humanos , Conectoma/métodos , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
5.
bioRxiv ; 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35132408

RESUMEN

The Coronavirus Disease 2019 (COVID-19) has affected all aspects of life around the world. Neuroimaging evidence suggests the novel coronavirus can attack the central nervous system (CNS), causing cerebro-vascular abnormalities in the brain. This can lead to focal changes in cerebral blood flow and metabolic oxygen consumption rate in the brain. However, the extent and spatial locations of brain alterations in COVID-19 survivors are largely unknown. In this study, we have assessed brain functional connectivity (FC) using resting-state functional MRI (RS-fMRI) in 38 (25 males) COVID patients two weeks after hospital discharge, when PCR negative and 31 (24 males) healthy subjects. FC was estimated using independent component analysis (ICA) and dual regression. When compared to the healthy group, the COVID group demonstrated significantly enhanced FC in the basal ganglia and precuneus networks (family wise error (fwe) corrected, pfwe < 0.05), while, on the other hand, reduced FC in the language network (pfwe < 0.05). The COVID group also experienced higher fatigue levels during work, compared to the healthy group (p < 0.001). Moreover, within the precuneus network, we noticed a significant negative correlation between FC and fatigue scores across groups (Spearman's ρ = -0.47, p = 0.001, r2 = 0.22). Interestingly, this relationship was found to be significantly stronger among COVID survivors within the left parietal lobe, which is known to be structurally and functionally associated with fatigue in other neurological disorders.

6.
Neuroimage Rep ; 2(2): 100095, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35496469

RESUMEN

Background: Among systemic abnormalities caused by the novel coronavirus, little is known about the critical attack on the central nervous system (CNS). Few studies have shown cerebrovascular pathologies that indicate CNS involvement in acute patients. However, replication studies are necessary to verify if these effects persist in COVID-19 survivors more conclusively. Furthermore, recent studies indicate fatigue is highly prevalent among 'long-COVID' patients. How morphometry in each group relate to work-related fatigue need to be investigated. Method: COVID survivors were MRI scanned two weeks after hospital discharge. We hypothesized, these survivors will demonstrate altered gray matter volume (GMV) and experience higher fatigue levels when compared to healthy controls, leading to stronger correlation of GMV with fatigue. Voxel-based morphometry was performed on T1-weighted MRI images between 46 survivors and 30 controls. Unpaired two-sample t-test and multiple linear regression were performed to observe group differences and correlation of fatigue with GMV. Results: The COVID group experienced significantly higher fatigue levels and GMV of this group was significantly higher within the Limbic System and Basal Ganglia when compared to healthy controls. Moreover, while a significant positive correlation was observed across the whole group between GMV and self-reported fatigue, COVID subjects showed stronger effects within the Posterior Cingulate, Precuneus and Superior Parietal Lobule. Conclusion: Brain regions with GMV alterations in our analysis align with both single case acute patient reports and current group level neuroimaging findings. We also newly report a stronger positive correlation of GMV with fatigue among COVID survivors within brain regions associated with fatigue, indicating a link between structural abnormality and brain function in this cohort.

7.
Int J Mol Sci ; 23(7)2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35409386

RESUMEN

Liberibacter is a group of plant pathogenic bacteria, transmitted by insect vectors, psyllids (Hemiptera: Psylloidea), and has emerged as one of the most devastating pathogens which have penetrated into many parts of the world over the last 20 years. The pathogens are known to cause plant diseases, such as Huanglongbing (citrus greening disease), Zebra chip disease, and carrot yellowing, etc., threatening some very important agricultural sectors, including citrus, potato and others. Candidatus Liberibacter asiaticus (CLas), the causative agent of citrus greening disease, is one of the most important pathogens of this group. This pathogen has infected most of the citrus trees in the US, Brazil and China, causing tremendous decline in citrus productivity, and, consequently, a severely negative impact on economic and personnel associated with citrus and related industries in these countries. Like other members in this group, CLas is transmitted by the Asian citrus psyllid (ACP, Diaphorina citri) in a persistent circulative manner. An additional important member of this group is Ca. L. solanacearum (CLso), which possesses nine haplotypes and infects a variety of crops, depending on the specific haplotype and the insect vector species. Ongoing pathogen control strategies, that are mainly based on use of chemical pesticides, lack the necessary credentials of being technically feasible, and environmentally safe. For this reason, strategies based on interference with Liberibacter vector transmission have been adopted as alternative strategies for the prevention of infection by these pathogens. A significant amount of research has been conducted during the last 10-15 years to understand the aspects of transmission of these bacterial species by their psyllid vectors. These research efforts span biological, ecological, behavioural and molecular aspects of Liberibacter-psyllid interactions, and will be reviewed in this manuscript. These attempts directed towards devising new means of disease control, endeavoured to explore alternative strategies, instead of relying on using chemicals for reducing the vector populations, which is the sole strategy currently employed and which has profound negative effects on human health, beneficial organisms and the environment.


Asunto(s)
Citrus , Hemípteros , Rhizobiaceae , Animales , Citrus/microbiología , Hemípteros/microbiología , Liberibacter , Enfermedades de las Plantas/microbiología
8.
medRxiv ; 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34845462

RESUMEN

Background: Among systemic abnormalities caused by the novel coronavirus, little is known about the critical attack on the central nervous system (CNS). Few studies have shown cerebrovascular pathologies that indicate CNS involvement in acute patients. However, replication studies are necessary to verify if these effects persist in COVID-19 survivors more conclusively. Furthermore, recent studies indicate fatigue is highly prevalent among 'long-COVID' patients. How morphometry in each group relate to work-related fatigue need to be investigated. Method: COVID survivors were MRI scanned two weeks after hospital discharge. We hypothesized, these survivors will demonstrate altered gray matter volume (GMV) and experience higher fatigue levels when compared to healthy controls, leading to stronger correlation of GMV with fatigue. Voxel-based morphometry was performed on T1-weighted MRI images between 46 survivors and 30 controls. Unpaired two-sample t-test and multiple linear regression were performed to observe group differences and correlation of fatigue with GMV. Results: The COVID group experienced significantly higher fatigue levels and GMV of this group was significantly higher within the Limbic System and Basal Ganglia when compared to healthy controls. Moreover, while a significant positive correlation was observed across the whole group between GMV and self-reported fatigue, COVID subjects showed stronger effects within the Posterior Cingulate, Precuneus and Superior Parietal Lobule . Conclusion: Brain regions with GMV alterations in our analysis align with both single case acute patient reports and current group level neuroimaging findings. We also newly report a stronger positive correlation of GMV with fatigue among COVID survivors within brain regions associated with fatigue, indicating a link between structural abnormality and brain function in this cohort.

9.
Indian J Occup Environ Med ; 26(4): 255-260, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37033750

RESUMEN

Context: The precarious nature of the work in the unorganized e-waste processing sector poses a threat to workers' health by making them vulnerable to occupational injuries as well as other work-related diseases in addition to job insecurity and related issues. Aims: To systematically explore and quantify employment and working conditions along with the occupational health problems and healthcare-seeking practices of workers processing e-waste in the slums of a south Indian city. Settings and Design: Cross-sectional study conducted in the slums of a south Indian city. Methods and Material: We used a structured interview schedule among 248 randomly selected workers. Statistical Analysis Used: Descriptive statistics were utilized to summarize the results. 95% CI was calculated for select proportions. Chi-square tests were used to determine statistical significance. Results: We found a predominance of self-employment; unclear employment relationship; no paid holidays; long working hours; unequal wages; absence of work-related social security; absent workers' organization; rented units; minimal/no use of safety equipment, no concept of good ergonomic practices. The commonest occupational health concerns were injuries (17% & 41% respectively) and musculoskeletal problems (43.5%). Private/charitable clinics were the commonest source of seeking healthcare which contributed to 'irrational' practices in the form of repeated TT injections. Conclusions: Findings suggest that the precarious work in the unorganized e-waste processing sector could not only give rise to health problems but also make workers undermine the severity of their health problems. The non-responsiveness of the local public healthcare system compels them to rely on private and charitable clinics and pay for services that are otherwise freely available in UPHCs.

10.
Indian J Med Ethics ; VI(3): 1-5, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34287203

RESUMEN

Ethical guidelines mandate that the researcher must obtain written informed consent either from the participant or from an impartial witness before commencing data collection. This case study describes some issues faced in trying to put this into practice. The research project in which these issues arose aimed to study occupational health problems and healthcare-seeking practices among workers in the unorganised e-waste sector in a south Indian city. The process of collecting written informed consent proceeded smoothly until the passage of the Citizenship Amendment Act. This made these workers extremely anxious. They were ready to participate but refused to sign any document. In these circumstances, identifying an "impartial witness" or a "study independent person", the recommended alternative to written consent by the institutional ethics committee, was impossible, given the close-knit community that was being studied and the fact that everyone was involved in one way or the other with e-waste related work.

.


Asunto(s)
Consentimiento Informado , Investigadores , Comités de Ética , Humanos , Proyectos de Investigación
11.
Int J Health Serv ; 51(1): 107-114, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33092455

RESUMEN

During the nationwide lockdown as part of the state response to the COVID-19 pandemic, the predicament of interstate migrant laborers in India, caught in crowded cities without means of livelihood and basic resources needed to sustain life, gained national and international attention. This article explores the context of the current migrant crisis through the historical trajectories and political roots of internal migration in India and its relationship with the urban informal labor market and the structural determinants of precarious employment. We argue that the both the response to the pandemic and the disproportionate impact on migrant laborers are reflections and consequences of an established pattern of neglect and poor accountability of the state toward the employment and living conditions of migrant workers who toil precariously in the informal labor market.


Asunto(s)
COVID-19/epidemiología , Control de Enfermedades Transmisibles/organización & administración , Migrantes , Países en Desarrollo , Política de Salud , Humanos , India/epidemiología , Pandemias , Política , Dinámica Poblacional , Vigilancia de la Población/métodos , Práctica de Salud Pública , SARS-CoV-2
12.
Indian J Occup Environ Med ; 23(1): 7-14, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31040583

RESUMEN

E-waste being hazardous in nature demands scientific management thereby protecting and safeguarding the health of the workers. A major chunk of e-waste ends up in informal sectors where crude methods are employed thereby risking the health of workers. The current scoping review, Based on Arksey and O'Malley's framework was done to explore the available literature to summarize the perceived and manifested health problems among informal e-waste workers. A literature search was done in three databases namely PubMed, Web of Science and ScienceDirect between 1/01/2010 and 1/01/2018. All the titles and abstracts were scrutinized to include only those studies on the basis of health symptoms/problems among workers. Health problems, thus explored, were categorized into five broad categories- physical injuries, respiratory, skin, musculoskeletal, and other general health problems. Major factors which could be related to health problems were job designation, age, non-usage of personal protective equipment, exposure to dust, and hazardous chemicals.

13.
Environ Sci Pollut Res Int ; 24(31): 24714-24724, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28936573

RESUMEN

Beauveria bassiana plays a prominent role in biocontrol of houseflies, Musca domestica (L.). Thus, a deeper insight into immune response of M. domestica during B. bassiana infection was warranted to assist the production of more efficient mycoinsecticides. The present study investigates changes in protein profile of M. domestica hemolymph serum post B. bassiana infection using two-dimensional difference gel electrophoresis (2D-DIGE) followed by identification of selected proteins by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). The non-infected or control group of flies showed an expression of 54 proteins, while M. domestica infected with B. bassiana expressed a total of 68 hemolymph serum proteins. Thirty three proteins were expressed in both groups of houseflies, whereas 35 proteins were exclusively expressed in infected flies and 21 proteins were exclusively expressed in control flies. Among the 33 proteins which were expressed in both groups of houseflies, 17 proteins showed downregulation, while16 proteins were upregulated in the infected flies compared to the non-infected ones. The results from this study are expected to facilitate better understanding of insect's immune response mechanism.


Asunto(s)
Beauveria/fisiología , Proteínas Sanguíneas/metabolismo , Moscas Domésticas/microbiología , Animales , Electroforesis en Gel Bidimensional , Hemolinfa/metabolismo , Moscas Domésticas/inmunología , Control Biológico de Vectores/métodos
14.
Environ Sci Pollut Res Int ; 24(27): 21948-21959, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28782085

RESUMEN

Contamination of environment and food from the prevalent spores and mycotoxins of Aspergillus niger has led to several diseases in humans and other animals. The present study investigated the control activity of plant essential oils against three strains of A. niger. In the elaborate assays done through microdilution plate assay and agar disk diffusion assay in the lab condition and in vivo assay on the stored wheat grains, the essential oil of Thymus vulgaris depicted overall superior efficacy. In microdilution plate assay, the oil of Anethum graveolens showed best fungistatic activity, while best fungicidal activity was depicted by Syzygium aromaticum oil. The oil of T. vulgaris showed moderate control efficacy against A. niger strains with its antifungal activity resulting mainly due to killing of microorganism rather than growth inhibition. In agar disk diffusion assay, T. vulgaris oil with a zone of inhibition (ZOI) of 23.3-61.1% was the most effective fungicide. The in vivo assay to evaluate the protection efficacy of oils for stored wheat grains against A. niger (AN1) revealed T. vulgaris (90.5-100%) to be the best control agent, followed by the oil of S. aromaticum (61.9-100%). The GC-MS analysis of T. vulgaris oil indicated the presence of thymol (39.11%), γ-terpinene (19.73%), o-cymene (17.21%), and ß-pinene (5.38%) as major oil components. Phytotoxic effects of the oils on wheat seeds showed no significant phytotoxic effect of oils in terms of seed germination or seedling growth. The results of the study demonstrated control potentiality of essential oils for the protection of stored wheat against A. niger with prospect for development of eco-friendly antifungal products.


Asunto(s)
Aspergillus niger/efectos de los fármacos , Fungicidas Industriales/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Timol/química , Animales , Grano Comestible/microbiología , Fungicidas Industriales/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Triticum/microbiología
15.
J Parasit Dis ; 41(2): 543-550, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28615876

RESUMEN

Microscopic investigation was done to determine the effect of entomopathogenic fungi, Beauveria bassiana and essential oil of Cymbopogon citratus on different life stages of Musca domestica. Scanning electron microscopy investigation of fungal infected larvae showed sluggish movement, rigor, and failure of body to balance in water. Treated larvae also revealed varied level of cuticle shrinkage and extreme dehydration. Surface of B. bassiana infected pupae showed varied stage of mycelial growth, while the cadaver of adult fly was observed to have extensive fungal growth covering their entire body surface. The application of C. citratus oils on M. domestica larvae resulted in skin shrinkage, spinous cells proliferation and bleb formation, while the treated pupae showed high incidence of incomplete emergence and malformation in emerged adult flies. The current study establishes effect of C. citratus essential oil and B. bassiana infection on different life stages of M. domestica.

16.
Indian J Occup Environ Med ; 21(3): 143-148, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29618915

RESUMEN

INTRODUCTION: Occupational Health hazards of handling and management of electronic waste is a nascent subject. Improper and unscientific handling of e-waste can invite significant human and environmental health risks. OBJECTIVE: To study the level of awareness about electronic waste and its health hazards amongst informal handlers in Musheerabad, Hyderabad. METHODOLOGY: Ethical approval and informed consents were obtained from Institutional Ethical Committee, University of Hyderabad and from the participants respectively before the commencement of study. This was a descriptive cross-sectional study conducted in randomly selected twenty-six waste handling centers from sixty of them in the locality. From each of the centers four handlers agedbetween 18 and 45 were randomly selected. Total of 104 handlers were interviewed using semi-structured schedule. Interviews were also conducted among 10 owners of such centres on the waste management practices. RESULTS: About 72% of the handlers did not know the meaning of electronic waste and 71% were not aware of associated health risks, 85% did not use any protective gears, while 16% acknowledged health issues attributed to improper handling of e-waste, 77% felt their handling of e-waste was appropriate. Majority of center owners felt that informal e-waste handling does not pose any health risks, and reported that there was no awareness campaign by any agency as of then. CONCLUSION: This study highlights the need for awareness campaigns on proper e-waste management practices to ensure occupational safety among the waste handlers who belong to lower socio-economic strata.

17.
J Food Sci Technol ; 53(10): 3725-3734, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28017987

RESUMEN

The control potential of seven plant essential oils was evaluated against Fusarium proliferatum (Matsushima) Nirenberg and Fusarium verticillioides Sheldon. The fungicidal activity was assessed through microtiter plate assay to determine the minimum inhibitory and fungicidal concentration of essential oils. The essential oil of Mentha arvensis was adjudged as best for inhibiting the fungal growth, while oil of Thymus vulgaris and Anethum graveolens showed high efficacy in terms of fungicidal activity. The oil of M. arvensis and T. vulgaris also showed good inhibition activity in agar disc diffusion assay. M. arvensis essential oil was analysed for its composition using gas chromatography/mass spectrometry revealing menthol (63.18 %), menthone (15.08 %), isomenthyl acetate (5.50 %) and limonene (4.31 %) as major components. Significant activity of M. arvensis essential oil against F. proliferatum and F. verticillioides isolates obtained, pave the way for its use as antifungal control agents.

18.
J Parasit Dis ; 39(4): 697-704, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26688637

RESUMEN

Beauveria bassiana HQ917687 virulence to housefly larvae and adult was assessed at different relative humidity, RH (50, 75, 90, and 100 %) and temperature (15, 20, 25, 30, 35, 40, 45 °C) conditions at the fungal dose of 10(8) conidia/ml. Depending on the temperature and RH regime tested, difference in mortality rates of housefly adult and larvae were detected. During assay on adult housefly, 100 % mortality was achieved at RH, 90 and 100 % while the temperature of 30 °C showed maximum mortality at all the tested humidity conditions. Lethal time, LT50 was 2.9 days at 100 % RH. Larval mortality at different humidity conditions varied between 30 and 74 %, with maximum mortality at 100 % RH and 30 °C. Optimum temperature for B. bassiana virulence to housefly larvae was also found to be 30 °C. The interaction between temperature and RH revealed significant effect of RH at moderate temperature range (20-35 °C), while such an interaction was not observed at extreme temperatures. The results obtained in this study have useful implications in understanding the pathogen behavior under actual field conditions. This in turn may help devising suitable entomopathogen release schedules for maximum fungal infection.

19.
Environ Sci Pollut Res Int ; 22(19): 15171-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26233748

RESUMEN

Entomopathogenic fungi that manifest infections by overcoming insect's immune response could be a successful control agent for the house fly, Musca domestica L. which is a major domestic, medical, and veterinary pest. In this study, the immune response of house fly to Beauveria bassiana infection was investigated to reveal fundamental aspects of house fly hemocyte biology, such as hemocyte numbers and size, which is poorly understood. The total hemocyte counts (THCs) in B. bassiana-infected house fly showed an initial increase (from 6 to 9 h), followed by subsequent decrease (9 to 12 h) with increase in time of infection. The THCs was slightly greater in infected flies than the non-infected ones. Insight into relative hemocyte counts depicted a significant increase in prohemocyte (PR) and decrease in granulocyte (GR) in infected house flies compared to non-infected ones. The relative cell area of hemocyte cells showed a noticeable increase in PR and intermediate cells (ICs), while a considerable reduction was observed for plasmatocyte (PL) and GR. The considerable variation in relative cell number and cell area in the B. bassiana-infected house flies indicated stress development during infection. The present study highlights changes occurring during B. bassiana invasion to house fly leading to establishment of infection along with facilitation in understanding of basic hemocyte biology. The results of the study is expected to help in better understanding of house fly immune response during fungal infection, so as to assist production of more efficient mycoinsecticides for house fly control using B. bassiana.


Asunto(s)
Beauveria/inmunología , Hemocitos/inmunología , Moscas Domésticas/inmunología , Moscas Domésticas/microbiología , Inmunidad Celular , Inmunidad Humoral , Animales , Recuento de Células , Tamaño de la Célula , Control Biológico de Vectores
20.
Environ Sci Pollut Res Int ; 22(19): 14793-800, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25989859

RESUMEN

The hexane and ether extracts of leaves, bark and roots of Jatropha curcas were screened for their toxicity against different developmental stages of housefly. The larvicidal, pupicidal and adulticidal activities were analysed at various concentrations (0.78-7.86 mg/cm(2)) of hexane and ether extracts. The lethal concentration values (LC50) of hexane extract of J. curcas leaves were 3.0 and 0.27 mg/cm(2) for adult and larval stages of housefly, respectively, after 48 h. Similarly, the ether extract of leaf showed the LC50 of 2.20 and 4.53 mg/cm(2) for adult and larval stages of housefly. Least toxicity was observed with hexane root extract of J. curcas with LC50 values of 14.18 and 14.26 mg/cm(2) for adult and larvae of housefly, respectively, after 48 h. The variation in LC50 against housefly pupae was found to be 8.88-13.10 mg/cm(2) at various J. curcas extract concentrations. The GC-MS analysis of J. curcas leaf extract revealed the presence of trans-phytol (60.81 %), squalene (28.58 %), phytol (2.52 %) and nonadecanone (1.06 %) as major components that could be attributed for insecticidal activity of J. curcas extracts.


Asunto(s)
Moscas Domésticas/efectos de los fármacos , Insecticidas/farmacología , Jatropha/química , Extractos Vegetales/farmacología , Animales , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Insecticidas/química , Insecticidas/aislamiento & purificación , Larva/efectos de los fármacos , Dosificación Letal Mediana , Fitol/química , Fitol/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Raíces de Plantas/química , Pupa/efectos de los fármacos , Escualeno/química , Escualeno/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA