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1.
Abstract Mulberry thrips Pseudodendrothrips mori (Niwa, 1908) is a major pest of mulberry trees recorded from different sericultural regions of the world. The thrips infestation affects the qualitative and quantitative characters of mulberry leaf, by direct feeding damage to leaves and the ingestion of sap, which in turn affects the silkworm cocoon crop. This is most harmful in dry climates and seasons when heavily attacked plants lose moisture heavily. Under these conditions infestation can seriously deplete yields. The seasonal population fluctuation and the degree of damage caused to the host plant are influenced by various environmental factors including climate, host-plant variety, topography, soil type, and management regimes. This article attempts to review all available documents on mulberry thrips and to discuss the practical approaches for best control of this pest. 相似文献
2.
Cristina V. Ariani Robert S. A. Pickles William C. Jordan Gisele Lobo-Hajdu Carlos Frederico D. Rocha 《Conservation Genetics》2013,14(5):943-951
Endemic and endangered species are highly vulnerable to habitat perturbations and may be subject to variations in their population size. Management plan for these species is crucial to avoid population decline, loss of genetic variability, inbreeding and ultimately extinction. The sand lizard, Liolaemus lutzae, is endemic to a habitat of sandy coastal plain (restinga). Its geographical distribution extends for only 200 km stretch of the coast of Rio de Janeiro state, Brazil, one of South America’s most densely populated regions. Extensive development and degradation of the beaches where the species inhabits, have led to the species becoming critically endangered. We used mitochondrial DNA sequences and microsatellite loci to resolve patterns of population connectivity and genetic variation within the species in order to provide a platform for a species management plan. Our results indicate the existence of three main populations, separated from each other by the Guanabara Bay and by the Arraial do Cabo Peninsula. The low microsatellite genetic variation and heterozygosity witnessed in each of the three populations, together with high levels of inbreeding and low effective population sizes suggest that the species is in urgent need of intensive management. Based on the results of this study we propose strong measures to protect existing restinga fragments and the implementation of programmes of captive breeding and reintroduction of individuals from the heavily threatened regions to protected refugia. Such measures may be the only way of ensuring the continuity of the species. 相似文献
3.
Ashwin Belle Sardar Ansari Maxwell Spadafore Victor A. Convertino Kevin R. Ward Harm Derksen Kayvan Najarian 《PloS one》2016,11(2)
Advanced hemodynamic monitoring is a critical component of treatment in clinical situations where aggressive yet guided hemodynamic interventions are required in order to stabilize the patient and optimize outcomes. While there are many tools at a physician’s disposal to monitor patients in a hospital setting, the reality is that none of these tools allow hi-fidelity assessment or continuous monitoring towards early detection of hemodynamic instability. We present an advanced automated analytical system which would act as a continuous monitoring and early warning mechanism that can indicate pending decompensation before traditional metrics can identify any clinical abnormality. This system computes novel features or bio-markers from both heart rate variability (HRV) as well as the morphology of the electrocardiogram (ECG). To compare their effectiveness, these features are compared with the standard HRV based bio-markers which are commonly used for hemodynamic assessment. This study utilized a unique database containing ECG waveforms from healthy volunteer subjects who underwent simulated hypovolemia under controlled experimental settings. A support vector machine was utilized to develop a model which predicts the stability or instability of the subjects. Results showed that the proposed novel set of features outperforms the traditional HRV features in predicting hemodynamic instability. 相似文献
4.
Mortazavi-Haghighat R Taghipour-Khiabani K David S Kerrigan CL Philip A 《American journal of physiology. Cell physiology》2002,282(5):C1161-C1169
Thepathophysiological mechanisms involved in ischemia-reperfusioninjury are poorly understood. Although transforming growth factor(TGF)- has been shown to provide protection againstischemia-reperfusion injury in different organ systems, littleis known about the regulation of TGF- action during this process.Here we analyzed the effect of ischemia and reperfusion on theexpression of TGF- and its receptors in vivo with a pig skin flapmodel. Analysis of unoperated skin, nonischemic control flap,ischemic flap, and reperfused flap by immunohistochemistryindicates that ischemia and reperfusion result in rapid anddynamic regulation of type I, II, and III TGF- receptors andTGF-1 in a cell type-specific manner. Furthermore, hypoxiaupregulates type II TGF- receptor mRNA in skin fibroblasts inculture. Together, our results reveal that TGF- receptors andTGF-1 are markedly increased under acute ischemic conditions in the blood vessels and fibroblasts of the skin. We conclude thatTGF- action is enhanced under ischemic conditions and that it may represent an adaptive response to ischemic injury. The augmented TGF- responsiveness may be a critical determinant of theprotective effect of TGF- during ischemia-reperfusion injury. 相似文献
5.
Brian J. Dewar Kayvan Keshari Rex Jeffries Petras Dzeja Lee M. Graves Jeffrey M. Macdonald 《Metabolomics : Official journal of the Metabolomic Society》2010,6(3):439-450
The goal of this study was to examine metabolic differences between a novel chronic myelogenous leukemic (CML) cell line,
MyL, and a sub-clone, MyL-R, which displays enhanced resistance to the targeted Bcr-Abl tyrosine kinase inhibitor imatinib.
1H nuclear magnetic resonance (NMR) spectroscopy was carried out on cell extracts and conditioned media from each cell type.
Both principal component analysis (PCA) and specific metabolite identification and quantification were used to examine metabolic
differences between the cell types. MyL cells showed enhanced glucose removal from the media compared to MyL-R cells with
significant differences in production rates of the glycolytic end-products, lactate and alanine. Interestingly, the total
intracellular creatine pool (creatine + phosphocreatine) was significantly elevated in MyL-R compared to MyL cells. We further
demonstrated that the MyL-R cells converted the creatine to phosphocreatine using non-invasive monitoring of perfused alginate-encapsulated
MyL-R and MyL cells by in vivo 31P NMR spectroscopy and subsequent HPLC analysis of extracts. Our data demonstrated a clear difference in the metabolite profiles
of drug-resistant and sensitive cells, with the biggest difference being an elevation of creatine metabolites in the imatinib-resistant
MyL-R cells. 相似文献
6.
桑蓟马Pseudodendrothrips mori是桑树的一种主要害虫。它的寄生直接影响供桑叶的质量和产量。我们通过泰勒幂法则和Morisita的散度指标对桑树蓟马在植株和桑园内的空间分布进行检验,结果显示:P.mori种群在植株内和桑园里的分布都存在局部化。桑树中蓟马的分布在树内显示出幼虫蓟马位于低层(从上面叶子起5-10层),但成虫更喜欢上层(从上面叶子起1-5层)。同一植株叶子的不同方向上蓟马密度没有出现明显变化。桑园内蓟马主要分布在桑园东部、南部和北部的植株上,中部,西部植株上的蓟马密度较低。P.mori的成虫和幼虫在叶子上的分布呈现明显聚集化。 相似文献
7.
Barbosa AC do Carmo AE Graf L Tomaz R de Souza CF Mendes J Randi MA Buchi D Schadeck RJ 《Canadian journal of microbiology》2006,52(2):117-124
Colletotrichum acutatum may develop one or more secondary conidia after conidial germination and before mycelial growth. Secondary conidia formation and germination were influenced by conidia concentration. Concentrations greater than 1x105 conidia/mL were associated with germination decrease and with secondary conidia emergence. Secondary conidia can form either alone or simultaneously with germ tubes and appressoria. Confocal analysis showed numerous lipid bodies stored inside ungerminated conidia, which diminished during germ tube and appressoria formation, with or without secondary conidia formation. They were also reduced during secondary conidia formation alone. While there was a decrease inside germinated conidia, lipid bodies appeared inside secondary conidia since the initial stages. Intense vacuolization inside primary germinated conidia occurred at the same time as the decrease in lipid bodies, which were internalized and digested by vacuoles. During these events, small acidic vesicles inside secondary conidia were formed. Considering that the conidia were maintained in distilled water, with no exogenous nutrients, it is clear that ungerminated conidia contain enough stored lipids to form germ tubes, appressoria, and the additional secondary conidia replete with lipid reserves. These results suggested a very complex and well-balanced regulation that makes possible the catabolic and anabolic pathways of these lipid bodies. 相似文献
8.
Ariani N Vissink A van Oort RP Kusdhany L Djais A Rahardjo TB van der Mei HC Krom BP 《Biofouling》2012,28(6):583-591
The composition of microbial biofilms on silicone rubber facial prostheses was investigated and compared with the microbial flora on healthy and prosthesis-covered skin. Scanning electron microscopy showed the presence of mixed bacterial and yeast biofilms on and deterioration of the surface of the prostheses. Microbial culturing confirmed the presence of yeasts and bacteria. Microbial colonization was significantly increased on prosthesis-covered skin compared to healthy skin. Candida spp. were exclusively isolated from prosthesis-covered skin and from prostheses. Biofilms from prostheses showed the least diverse band-profile in denaturing gradient gel electrophoresis (DGGE) whereas prosthesis-covered skin showed the most diverse band-profile. Bacterial diversity exceeded yeast diversity in all samples. It is concluded that occlusion of the skin by prostheses creates a favorable niche for opportunistic pathogens such as Candida spp. and Staphylococcus aureus. Biofilms on healthy skin, skin underneath the prosthesis and on the prosthesis had a comparable composition, but the numbers present differed according to the microorganism. 相似文献
9.
Kar UK Jiang J Champion CI Salehi S Srivastava M Sharma S Rabizadeh S Niazi K Kickhoefer V Rome LH Kelly KA 《PloS one》2012,7(7):e38553
Background
Modifications of adjuvants that induce cell-mediated over antibody-mediated immunity is desired for development of vaccines. Nanocapsules have been found to be viable adjuvants and are amenable to engineering for desired immune responses. We previously showed that natural nanocapsules called vaults can be genetically engineered to elicit Th1 immunity and protection from a mucosal bacterial infection. The purpose of our study was to characterize immunity produced in response to OVA within vault nanoparticles and compare it to another nanocarrier.Methodology and Principal Findings
We characterized immunity resulting from immunization with the model antigen, ovalbumin (OVA) encased in vault nanocapsules and liposomes. We measured OVA responsive CD8+ and CD4+ memory T cell responses, cytokine production and antibody titers in vitro and in vivo. We found that immunization with OVA contain in vaults induced a greater number of anti-OVA CD8+ memory T cells and production of IFNγ plus CD4+ memory T cells. Also, modification of the vault body could change the immune response compared to OVA encased in liposomes.Conclusions/Significance
These experiments show that vault nanocapsules induced strong anti-OVA CD8+ and CD4+ T cell memory responses and modest antibody production, which markedly differed from the immune response induced by liposomes. We also found that the vault nanocapsule could be modified to change antibody isotypes in vivo. Thus it is possible to create a vault nanocapsule vaccine that can result in the unique combination of immunogen-responsive CD8+ and CD4+ T cell immunity coupled with an IgG1 response for future development of vault nanocapsule-based vaccines against antigens for human pathogens and cancer. 相似文献10.
KayvanEtebari L.Matindoost R.N.Singh 《Entomologia Sinica》2004,11(4):243-255
Mulberry thrips Pseudodendrothrips mori (Niwa, 1908) is a major pest of mulberry trees recorded from different sericultural regions of the world. The thrips infestation affects the qualitative and quantitative characters of mulberry leaf, by direct feeding damage to leaves and the ingestion of sap, which in turn affects the silkworm cocoon crop. This is most harmful in dry climates and seasons when heavily attacked plants lose moisture heavily. Under these conditions infestation can seriously deplete yields. The seasonal population fluctuation and the degree of damage caused to the host plant are influenced by various environmental factors including climate, host-plant variety, topography, soil type, and management regimes.This article attempts to review all available documents on mulberry thrips and to discuss the practical approaches for best control of this pest. 相似文献