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1.
K. Tennekone M. G. C. Peiris W. M. R. Divigalpitiya S. Ariyaratne 《Journal of biological physics》1979,7(1):26-38
The flowers of malvaceae family preserves the symmetry between right and left in a peculiar manner. Plots belonging to this
family bear two kinds of flowers, right-handed flowers with anticlockwise twisted petals and left-handed flowers with clockwise
twisted petals. The branches of the plant prefers production of one type of flowers in excess of the other. There are two
distinct types of branches, dextral branches and sinistral branches. Dextral (sinistral) branches produce more right-handed
(left-handed) flowers than left-handed (right-handed) flowers. The average percentage of right-handed flowers in a dextral
branch is same as that of left-handed flowers in a sinistral branch. 相似文献
2.
Summary ATrichoderma sp. (IMB-Tr) isolated from rice straw possessed cellulolytic and xylanolytic activity, comparable to those produced byTrichoderma reesei QM 9414 (a proven cellulolytic fungus). IMB-Tr produced 2.9 and 1.9 times, respectively, greater -glucosidase activity compared toT. reesei when grown on microcrystalline cellulose and rice straw. Percentage enzymic hydrolysis increased with increase in the sodium hydroxide concentration used in the pretreatment of rice straw and with the increase of enzyme concentration used in the hydrolysis. The extracellular enzyme fraction ofT. reesei possessed greater hydrolytic power than that of IMB-Tr. However, when a combined enzyme preparation from the two organisms was used, an appreciable degree of synergism was observed; an increase in reducing sugars up to 39% was seen. The reducing sugar produced by enzymic hydrolysis was mainly glucose, xylose and cellobiose. Fermentation of a 4.8% (w/v) sugar hydrolysate (produced by the enzymic hydrolysis of rice straw) bySaccharomyces cerevisiae produced 10.7 g/l of ethanol compared to 18.8 g/l produced by the fermentation of 4.8% (w/v) pure glucose.
Resumen Se ha aíslado a partir de paja de arroz una cepa deTrichoderma sp. (IMB-Tr) que posee actividades celulolíticas y xilanolíticas comparables a las deTrichoderma reesei QM 9414 (un hongo probadamnete celulolítico). IMB-Tr produjo 2.9 y 1.9 veces más actividad -glucosidásica queT. reesei cuando ambos se hicieron crecer en celulosa microcristalina y en paja de arroz respectivamente. El porcentaje de hidrolisis enzimática se incrementó con el aumento en la concentración del hidróxido sódico empleado en el pretratamiento de la paja de arroz y con el aumento de la concentración enzimática utilizada en la hidrolisis. La fracción extracelular enzimática deT. reesei poseía un mayor poder hidrolítico que la de IMB-Tr, sin embargo cuando se usó un preparado enzimático combinado de ambos microorganismos se obtuvo un apreciable efecto sinérgico, observándose un incremento de hasta un 39% de los azucares reductores producidos. Estos azucares fueron principalmente glucosa, xilosa y celobiosa. La fermentación de un 4.8% (p/v) del hidrolisado azucarado (producido por la hidrolisis enzimática de la paja de arroz) porSaccharomyces cerevisiae produjo 10.7 g/l de etanol comparado a 18.8 g/l obtenidos de la fermentación de 4.8% (p/v) de glucosa pura.
Résumé Une souche deTrichoderma sp. (IMB-Tr), isolée à partir de paille de riz, a une activité cellulolytique et xylanolytique comparable à celle deTrichoderma reesei QM 9414 (champignon cellulolytique reconnu). L'activité -glucosidase d'IMB-Tr cultivé sur cellulose micro-cristalline ou sur paille de riz est, respectivement, 2.9 et 1.9 fois plus élevée que celle deT. reesei. Le pourcentage d'hydrolyse enzymatique croit avec la concentration de la soude employée pour le pré-traitement de la paille et avec la concentration d'enzyme utilisée pour l'hydrolyse. La fraction exocellulaire de l'enzyme a une activité hydrolysante plus élevée dans le cas deT. reesei que dans celui de IMB-Tr. Cependant, si on emploie un mélange des activités enzymatiques des deux organismes, on constate une nette synergie et un accroissement des sucres réducteurs allant jusqu'à 39%. Les sucres réducteurs obtenus par hydrolyse enzymatique comprennent principalement du glucose, du xylose et du cellobiose. La fermentation parSaccharomyces cerevisiae d'un hydrolysat enzymatique de paille de riz contenant 4.8% (poids/vol.) de sucres fournit 10.7 g/l d'éthanol, au lieu de 18.8 g/l obtenus par fermentation de glucose pur à la même concentration.相似文献
3.
A. Mohammad J.S.M. Peiris E.A. Wijewanta S. Mahalingam G. Gunasekara 《FEMS microbiology letters》1985,26(3):281-283
Abstract 273 Strains of Escherichia coli isolated from diarrhoeic and healthy control cattle and buffalo calves in Sri Lanka, were tested for Verocytotoxin (VT) and for heat-stable (ST) and heat-labile (LT) enterotoxins. VT and ST toxigenic E. coli were significantly associated with diarrhoea, accounting for 28% and 18% of diarrhoeic episodes, respectively. LT toxigenic E. coli were not significantly associated with diarrhoea. 相似文献
4.
Serotypes of verocytotoxigenic Escherichia coli isolated from cattle and buffalo calf diarrhoea 总被引:1,自引:0,他引:1
Abstract Parasporal crystals of the recently isolated Bacillus thuringiensis var. tenebrionis are toxic for coleopteran larvae. Unlike those of other strains they are soluble either in aqueous solutions of NaBr at neutral pH or in water after titration to pH values above pH 10.0. The dissolved crystal protein readily forms crystals after removal of the salt or neutralization. The crystal protein was not found to differ much in the amino acid composition from other crystal proteins. The parasporal crystals are composed of subunits of M r 68 000 which are not linked by disulfide bridges. 相似文献
5.
6.
Cardiovascular disease (CVD) risk in India is currently assessed using the World Health Organization/International Society for Hypertension (WHO/ISH) risk prediction charts since no population-specific models exist. The WHO/ISH risk prediction charts have two versions—one with total cholesterol as a predictor (the high information (HI) model) and the other without (the low information (LI) model). However, information on the WHO/ISH risk prediction charts including guidance on which version to use and when, as well as relative performance of the LI and HI models, is limited. This article aims to, firstly, quantify the relative performance of the LI and HI WHO/ISH risk prediction (for WHO-South East Asian Region D) using data from rural India. Secondly, we propose a pre-screening (simplified) point-of-care (POC) test to identify patients who are likely to benefit from a total cholesterol (TC) test, and subsequently when the LI model is preferential to HI model. Analysis was performed using cross-sectional data from rural Andhra Pradesh collected in 2005 with recorded blood cholesterol measurements (N = 1066). CVD risk was computed using both LI and HI models, and high risk individuals who needed treatment(T
HR) were subsequently identified based on clinical guidelines. Model development for the POC assessment of a TC test was performed through three machine learning techniques: Support Vector Machine (SVM), Regularised Logistic Regression (RLR), and Random Forests (RF) along with a feature selection process. Disagreement in CVD risk predicted by LI and HI WHO/ISH models was 14.5% (n = 155; p<0.01) overall and comprised 36 clinically relevant T
HR patients (31% of patients identified as T
HR by using either model). Using two patient-specific parameters (age, systolic blood pressure), our POC assessment can pre-determine the benefit of TC testing and choose the appropriate risk model (out-of-sample AUCs:RF-0.85,SVM-0.84,RLR:0.82 and maximum sensitivity-98%). The identification of patients benefitting from a TC test for CVD risk stratification can aid planning for resource-allocation and save costs for large-scale screening programmes. 相似文献
7.
Mark P. Zanin Kimberly D. Mackenzie Heshan Peiris Melanie A. Pritchard Damien J. Keating 《Journal of neurochemistry》2013,124(3):290-299
We have previously shown that Regulator of Calcineurin 1 (RCAN1) regulates multiple stages of vesicle exocytosis. However, the mechanisms by which RCAN1 affects secretory vesicle exocytosis and quantal release kinetics remain unknown. Here, we use carbon fibre amperometry to detect exocytosis from chromaffin cells and identify these underlying mechanisms. We observe reduced exocytosis with repeated stimulations in chromaffin cells over‐expressing RCAN1 (RCAN1ox), but not in wild‐type (WT) cells, indicating a negative effect of RCAN1 on vesicle recycling and endocytosis. Acute exposure to calcineurin inhibitors, cyclosporine A and FK‐506, replicates this effect in WT cells but has no additional effect in RCAN1ox cells. When we chronically expose WT cells to cyclosporine A and FK‐506 we find that catecholamine release per vesicle and pre‐spike foot (PSF) signal parameters are decreased, similar to that in RCAN1ox cells. Inhibiting calcineurin activity in RCAN1ox cells has no additional effect on the amount of catecholamine release per vesicle but further reduces PSF signal parameters. Although electron microscopy studies indicate these changes are not because of altered vesicle number or distribution in RCAN1ox cells, the smaller vesicle and dense core size we observe in RCAN1ox cells may underlie the reduced quantal release in these cells. Thus, our results indicate that RCAN1 most likely affects vesicle recycling and quantal release kinetics via the inhibition of calcineurin activity. 相似文献
8.
Devarsetty?PraveenEmail author Anushka?Patel Stephen?McMahon Dorairaj?Prabhakaran Gari?D.?Clifford Pallab?K.?Maulik Rohina?Joshi Stephen?Jan Stephane?Heritier David?Peiris 《Implementation science : IS》2013,8(1):137
Background
Blood Pressure related disease affected 118 million people in India in the year 2000; this figure will double by 2025. Around one in four adults in rural India have hypertension, and of those, only a minority are accessing appropriate care. Health systems in India face substantial challenges to meet these gaps in care, and innovative solutions are needed.Methods
We hypothesise that a multifaceted intervention involving capacity strengthening of primary healthcare doctors and non-physician healthcare workers through use of a mobile device-based clinical decision support system will result in improved blood pressure control for individuals at high risk of a cardiovascular disease event when compared with usual healthcare. This intervention will be implemented as a stepped wedge, cluster randomised controlled trial in 18 primary health centres and 54 villages in rural Andhra Pradesh involving adults aged ≥40 years at high cardiovascular disease event risk (approximately 15,000 people). Cardiovascular disease event risk will be calculated based on World Health Organisation/International Society of Hypertension’s region-specific risk charts. Cluster randomisation will occur at the level of the primary health centres. Outcome analyses will be conducted blinded to intervention allocation.Expected outcomes
The primary study outcome is the difference in the proportion of people meeting guideline-recommended blood pressure targets in the intervention period vs. the control period. Secondary outcomes include mean reduction in blood pressure levels; change in other cardiovascular disease risk factors, including body mass index, current smoking, reported healthy eating habits, and reported physical activity levels; self-reported use of blood pressure and other cardiovascular medicines; quality of life (using the EQ-5D); and cardiovascular disease events (using hospitalisation data). Trial outcomes will be accompanied by detailed process and economic evaluations.Significance
The findings are likely to inform policy on a scalable strategy to overcome entrenched inequities in access to effective healthcare for under-served populations in low and middle income country settings.Trial registration
Clinical Trial Registry India CTRI/2013/06/003753.9.
10.
Cocirculation of Avian H9N2 and Contemporary “Human” H3N2 Influenza A Viruses in Pigs in Southeastern China: Potential for Genetic Reassortment? 总被引:11,自引:0,他引:11 下载免费PDF全文
Peiris JS Guan Y Markwell D Ghose P Webster RG Shortridge KF 《Journal of virology》2001,75(20):9679-9686
Pigs are permissive to both human and avian influenza viruses and have been proposed to be an intermediate host for the genesis of pandemic influenza viruses through reassortment or adaptation of avian viruses. Prospective virological surveillance carried out between March 1998 and June 2000 in Hong Kong, Special Administrative Region, People's Republic of China, on pigs imported from southeastern China, provides the first evidence of interspecies transmission of avian H9N2 viruses to pigs and documents their cocirculation with contemporary human H3N2 (A/Sydney/5/97-like, Sydney97-like) viruses. All gene segments of the porcine H9N2 viruses were closely related to viruses similar to chicken/Beijing/1/94 (H9N2), duck/Hong Kong/Y280/97 (H9N2), and the descendants of the latter virus lineage. Phylogenetic analysis suggested that repeated interspecies transmission events had occurred from the avian host to pigs. The Sydney97-like (H3N2) viruses isolated from pigs were related closely to contemporary human H3N2 viruses in all gene segments and had not undergone genetic reassortment. Cocirculation of avian H9N2 and human H3N2 viruses in pigs provides an opportunity for genetic reassortment leading to the emergence of viruses with pandemic potential. 相似文献