413 research outputs found
Reaction of lactim ethers and lactim sulfides with electrophiles: attackat nitrogen followed by ring-opening under neutral conditions
Electrophilic push-pull molecules react at the nitrogen of lactim ethers and lactim sulfides; subsequent hydrolysis gives ring-opened products in good yields
Profiling of Burkholderia cepacia Secretome at Mid-Logarithmic and Early-Stationary Phases of Growth
BACKGROUND: Burkholderia cepacia is a Gram-negative pathogen that causes serious respiratory infections in immunocompromised patients and individuals with cystic fibrosis. This bacterium is known to release extracellular proteins that may be involved in virulence. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, B. cepacia grown to mid-logarithmic and early-stationary phases were investigated on their ability to invade and survive intracellularly in A549 lung epithelial cells in order to discern the fate of these bacteria in the pathogenesis of B. cepacia lung infections in in vitro condition. The early-stationary phase B. cepacia was demonstrated to be more invasive than mid-logarithmic phase. In addition, culture supernatants of B. cepacia obtained from these phases of growth were also demonstrated to cause different cytotoxic potency on the A549 human lung epithelial cells. Profiling of the supernatants using the gel-based proteomics approach identified 43 proteins that were commonly released in both the growth phases and 40 proteins newly-released at the early-stationary phase. The latter proteins may account for the higher cytotoxic activity of the early-stationary culture supernatant compared to that obtained at the mid-logarithmic phase. Among the newly-released proteins in the early-stationary phase supernatant were flagellar hook-associated domain protein (FliD), flagellar hook-associated protein (FlgK), TonB-dependent siderophore (Fiu), Elongation factor G (FusA), phosphoglycerate kinase (Pgk) and sulfatase (AslA) which are known for their virulence. CONCLUSION/SIGNIFICANCE: Differences in the ability of B. cepacia to invade and survive intracellularly inside the epithelial cells at different phases of growth may improve our understanding of the varied disease progressions associated with B. cepacia infections. In addition, the identified culture supernatant proteins may be used as targets for the development of new strategies to control B. cepacia infection using agents that can block their release
Study of Seed Orientation in Different Depths in Jatropha Curcas L.
Seeds were sown in three orientations (Radicle downwards, radicle upwards and flat position) at four different depths (1, 2, 3 and 4 centimeters) to improve the germination on Jatropha curcas. The results revealed that sowing seed at 2 centimeter depth with radical downwards position enhanced the production of normal seedling and the germination percentage (85%). Compare to radicle downward and flat position of seed at different depth of sowing, speed of emergence and abnormal seedling existence were lower and higher respectively in radicle upward position of seeds with 4 centimeter depth
Detection of Wolbachia endobacteria in Culex quinquefasciatus by Gimenez staining and confirmation by PCR
Background & objectives: Wolbachia are common intracellular bacteria that are found in arthropods and nematodes.These endosymbionts are transmitted vertically through host eggs and alter host biology in diverse ways, includingthe induction of reproductive manipulations, such as feminization, parthenogenesis, male killing and sperm-eggincompatibility. Since they can also move horizontally across species boundaries, Wolbachia is gaining importancein recent days as it could be used as a biological control agent to control vector mosquitoes or for paratransgenicapproaches. However, the study of Wolbachia requires sophisticated techniques such as PCR and cell culturefacilities which cannot be affordable for many laboratories where the diseases transmitted by arthropod vectorsare common. Hence, it would be beneficial to develop a simple method to detect the presence of Wolbachia inarthropods.Method: In this study, we described a method of staining Wolbachia endobacteria, present in the reproductivetissues of mosquitoes. The reliability of this method was compared with Gram staining and PCR based detection.Results: The microscopic observation of the Gimenez stained smear prepared from the teased ovary of wildcaught and Wolbachia (+) Cx. quinquefasciatus revealed the presence of pink coloured pleomorphic cells ofWolbachia ranging from cocci, comma shaped cells to bacillus and chain forms. The ovaries of Wolbachia (–)cured mosquito did not show any cell. Although Gram’s staining is a reliable differential staining for the otherbacteria, the bacterial cells in the smears from the ovaries of wild caught mosquitoes did not take the stain properlyand the cells were not clearly visible. The PCR amplified product from the pooled remains of wild caught andWolbachia (+) Cx. quinquefasciatus showed clear banding, whereas, no banding was observed for the negativecontrol (distilled water) and Wolbachia (–) Cx. quinquefasciatus.Interpretation & conclusion: The Gimenez staining technique applied, could be used to detect the members of theendobacteria Wolbachia easily, even in a simple laboratory without any special facilities or even in the fieldcondition and for handling large number of samples in a shorter duratio
A Blueberry-Enriched Diet Attenuates Nephropathy in a Rat Model of Hypertension via Reduction in Oxidative Stress
To assess renoprotective effects of a blueberry-enriched diet in a rat model of hypertension. Oxidative stress (OS) appears to be involved in the development of hypertension and related renal injury. Pharmacological antioxidants can attenuate hypertension and hypertension-induced renal injury; however, attention has shifted recently to the therapeutic potential of natural products as antioxidants. Blueberries (BB) have among the highest antioxidant capacities of fruits and vegetables.Male spontaneously hypertensive rats received a BB-enriched diet (2% w/w) or an isocaloric control diet for 6 or 12 weeks or 2 days. Compared to controls, rats fed BB-enriched diet for 6 or 12 weeks exhibited lower blood pressure, improved glomerular filtration rate, and decreased renovascular resistance. As measured by electron paramagnetic resonance spectroscopy, significant decreases in total reactive oxygen species (ROS), peroxynitrite, and superoxide production rates were observed in kidney tissues in rats on long-term dietary treatment, consistent with reduced pathology and improved function. Additionally, measures of antioxidant status improved; specifically, renal glutathione and catalase activities increased markedly. Contrasted to these observations indicating reduced OS in the BB group after long-term feeding, similar measurements made in rats fed the same diet for only 2 days yielded evidence of increased OS; specifically, significant increases in total ROS, peroxynitrite, and superoxide production rates in all tissues (kidney, brain, and liver) assayed in BB-fed rats. These results were evidence of "hormesis" during brief exposure, which dissipated with time as indicated by enhanced levels of catalase in heart and liver of BB group.Long-term feeding of BB-enriched diet lowered blood pressure, preserved renal hemodynamics, and improved redox status in kidneys of hypertensive rats and concomitantly demonstrated the potential to delay or attenuate development of hypertension-induced renal injury, and these effects appear to be mediated by a short-term hormetic response
Towards Real-Time Visual Biometric Authentication Using Human Face for Healthcare Telepresence Mobile Robots
Telepresence Mobile Robots have prominent attributes in many fields as it provides virtual presence for human robot interaction. The deployment of this robot in healthcare sector has improved patient care and health. The vision system in a telepresence robot allows two way audiovisual communication between people at different location. In spite of such advancement, the manual way of controlling a robot to recognise and track people during an emergency is not favourable for a long duration. To circumvent this problem, biometric method using human face is proposed in this research which is implemented on Medical Telediagnosis Robot. This paper details the design of the face recognition and tracking system with four automated modules which are motion detection, face detection, face recognition and face tracking. The modules are developed with different algorithm and tested individually to ensure the stability of the system. Artificial Intelligence technique was applied at the face recognition stage while a two degree of freedom mechanism for actuator control was used at face tracking stage. A sequential mode operation is proposed to reduce the execution time in a real-time environment. To achieve this, only one module is operated at each time. A Graphical User Interface was developed to ease the users at the local and robot environment. The system is designed in LabVIEW platform. The biometric system proposed with hybrid algorithm at each module adapts for face images detected at different distances, poses and lighting condition. This system was tested in real-time and has an execution time of 55ms and 98% accuracy. The stand alone system designed for Medical Telediagnosis Robot can be will be very fruitful for various biometric system using facial technology
Analysis of Heart Beat Rate through Video Imaging Techniques
Health is the condition of being free from disease or injury either in physically or mentally. To provide a general state of health, analysis of physiological parameters such as heart beat rate, blood pressure, respiratory rate, hemoglobin concentration and etc. are playing an important part. Among these physiological parameters, heart beat rate is the most essential indicator of people’s health state because it is the heart rhythms to circulate the blood flow in the human body. Hence, in clinical diagnosis or for the patient in an intensive care unit, heart beat rate is the parameter that must be recorded and examined. The standard equipment like stethoscope, electrocardiogram, pulse oximetry are normally used for measuring heart beat rate but those equipment required to contact sensors to the human skin. In order to overcome the discomforts caused by the long period attachment of sensors and difficulties faced by patients who have skin damages, this research proposed a noncontact technique to measure heart beat rate through video imaging captured by an ordinary RGB camera. The acquired results from video imaging techniques are achieved more than 90% in accuracy by comparing with the results obtained through biomedical toolkit of LabVIEW. The developed techniques are attractive and suitable for regularly health care monitoring purposes due to its contactless, low cost, convenience, multiple people assessments and continuous benefits
Combined acute hyperglycemic and hyperinsulinemic clamp induced profibrotic and proinflammatory responses in the kidney
Increase in matrix protein content in the kidney is a cardinal feature of diabetic kidney disease. While renal matrix protein content is increased by chronic hyperglycemia, whether it is regulated by acute elevation of glucose and insulin has not been addressed. In this study, we aimed to evaluate whether short duration of combined hyperglycemia and hyperinsulinemia, mimicking the metabolic environment of prediabetes and early type 2 diabetes, induces kidney injury. Normal rats were subjected to either saline infusion (control, n = 4) or 7 h of combined hyperglycemic- hyperinsulinemic clamp (HG+HI clamp; n = 6). During the clamp, plasma glucose and plasma insulin were maintained at about 350 mg/dl and 16 ng/ml, respectively. HG+HI clamp increased the expression of renal cortical transforming growth factor-β (TGF-β) and renal matrix proteins, laminin and fibronectin. This was associated with the activation of SMAD3, Akt, mammalian target of rapamycin (mTOR) complexes, and ERK signaling pathways and their downstream target events in the initiation and elongation phases of mRNA translation, an important step in protein synthesis. Additionally, HG+HI clamp provoked renal inflammation as shown by the activation of Toll-like receptor 4 (TLR4) and infiltration of CD68-positive monocytes. Urinary F2t isoprostane excretion, an index of renal oxidant stress, was increased in the HG+HI clamp rats. We conclude that even a short duration of hyperglycemia and hyperinsulinemia contributes to activation of pathways that regulate matrix protein synthesis, inflammation, and oxidative stress in the kidney. This finding could have implications for the control of short-term rises in blood glucose in diabetic individuals at risk of developing kidney disease. © 2014 the American Physiological Society
Photodynamic versus white light-guided treatment of non-muscle invasive bladder cancer: a study protocol for a randomised trial of clinical and cost-effectiveness
Bladder cancer is the most frequently occurring tumour of the urinary system. Ta, T1 tumours and carcinoma in situ (CIS) are grouped as non-muscle invasive bladder cancer (NMIBC), which can be effectively treated by transurethral resection of bladder tumour (TURBT). There are limitations to the visualisation of tumours with conventional TURBT using white light illumination within the bladder. Incomplete resections occur from the failure to identify satellite lesions or the full extent of the tumour leading to recurrence and potential risk of disease progression. To improve complete resection, photodynamic diagnosis (PDD) has been proposed as a method that can enhance tumour detection and guide resection. The objective of the current research is to determine whether PDD-guided TURBT is better than conventional white light surgery and whether it is cost-effective.This article is freely available via Open Access. Click on the publisher URL to access the full-text from the publisher's site
Tuberculosis chemotherapy: current drug delivery approaches
Tuberculosis is a leading killer of young adults worldwide and the global scourge of multi-drug resistant tuberculosis is reaching epidemic proportions. It is endemic in most developing countries and resurgent in developed and developing countries with high rates of human immunodeficiency virus infection. This article reviews the current situation in terms of drug delivery approaches for tuberculosis chemotherapy. A number of novel implant-, microparticulate-, and various other carrier-based drug delivery systems incorporating the principal anti-tuberculosis agents have been fabricated that either target the site of tuberculosis infection or reduce the dosing frequency with the aim of improving patient outcomes. These developments in drug delivery represent attractive options with significant merit, however, there is a requisite to manufacture an oral system, which directly addresses issues of unacceptable rifampicin bioavailability in fixed-dose combinations. This is fostered by the need to deliver medications to patients more efficiently and with fewer side effects, especially in developing countries. The fabrication of a polymeric once-daily oral multiparticulate fixed-dose combination of the principal anti-tuberculosis drugs, which attains segregated delivery of rifampicin and isoniazid for improved rifampicin bioavailability, could be a step in the right direction in addressing issues of treatment failure due to patient non-compliance
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