21,891 research outputs found
Integrins alpha v beta 3 and alpha v beta 5 contribute to cell attachment to vitronectin but differentially distribute on the cell surface.
We investigated the role of the integrins alpha v beta 3 and alpha v beta 5 in mediating vitronectin adhesion of three phenotypically distinct cell types. M21 human melanoma cells and H2981 lung carcinoma cells use both alpha v-containing integrins in adhering to vitronectin while UCLA-P3 lung carcinoma cells adhere exclusively with alpha v beta 5. Specifically, monoclonal antibodies directed to functional epitopes on both receptors were required to block adhesion of M21 or H2981 cells while adhesion of UCLA-P3 cells to vitronectin could be blocked with a monoclonal antibody to alpha v beta 5. Although both receptors are involved in M21 and H2981 cell adhesion to vitronectin, only alpha v beta 3 can be detected in focal contacts, colocalizing with vinculin, talin, and the ends of actin filaments, while alpha v beta 5 shows a distinct, nonfocal contact, distribution on the cell surface. These results provide the first evidence that two homologous integrins that recognize the same ligand distribute differentially on the cell surface
Relationship between Creativity and Academic Achievement of Business Administration Students in South Western Polytechnics, Nigeria (
This study investigated relationship between students’ creativity and academic achievement as measured by the CGPA scores. Two instruments; Nicolas Holt Creativity Test (NHCT) and Student CGPA Information Format (SCIF) were respectively used to collect data on creativity and students’ CGPA scores of a sample of randomly selected 235 HNDII business administration students of Polytechnics in the South Western States of Nigeria. There was a very low negative insignificant relationship between creativity and CGPA scores (r=-0.004, p>0.05).Thus, the higher the students’ creativity, the lower the CGPA score. A creative person may not necessarily be a high achiever in school. In searching for people to carry out tasks that involve high creativity, level of academic achievement should not be the only requirement for selection.Keywords: Creativity, Academic Achievement, Business AdministrationStudents, Polytechnics, CGPA scores
Prevalence Of Tsetse Fly And Bovine Trypanosomosis In The Biological Control Of Tsetse Fly Project (Bicot) Within Afia Local Government Area Of Nasarawa State, Nigeria
The prevalence of tsetse fly and bovine trypanosomosis was studied in the biological control of tsetse fly project (BICOT) area within Lafia Local Government Area of Nasarawa state, Nigeria between May and November 2000. The project area, covering approximately 1500 km2 was virtually freed of Glossina palpalis palpalis and to some extent G tachinoides by Dec. 1984. By 1987, however, sterile male releases were suspended and remained so till the time of this study due to lack of funding. Ten biconical traps were set at an interval of 25 meters along each river/stream in the study area. In all, 466 flies were caught out of which 454 were G.p palpalis while the remaining 12 were G.tachinoides. The result of the dissection of the insects showed that 9 (1.9%) of tsetse flies caught were positive for Trypanosoma vivax. All infected flies were G.p palpalis. Also blood samples were collected from 200 cattle in the abattoir and 200 in the sedentary cattle in the area. The blood samples were examined using standard parasitological techniques. The result
showed that, in sedentary cattle, 18(9%) were positive for trypanosomes while in the abattoir 21(10.5%) were positive for trypanosomes. There was however no significant difference (p > 0.05) between the numbers of cases defected in sedentary cattle and abattoir cattle. Most of the infections in sedentary cattle (67%) and abattoir cattle (81%) were due to T. congolense. Keywords: Tsetse fly ,bovine trypanosomosis, biological control, LafiaJournal of Agriculture and Social Research Vol. 8 (1) 2008: pp. 8-1
Endoscopic injection sclerotherapy for bleeding varices in children with intrahepatic and extrahepatic portal venous obstruction: Benefit of injection tract embolisation
Background. The outcome of sclerotherapy for bleeding oesophagealvarices may be influenced by injection technique. In a previous study at our institution, sclerotherapy was associated with a high re-bleeding rate and oesophageal ulceration. Embolisation of the injection tract was introduced in an attempt to reduce injectionrelated complications.Methods. To determine the outcome and effectiveness of injectiontract embolisation in reducing injection-related complications, weretrospectively reviewed a series of 59 children who underwent injection sclerotherapy for oesophageal varices (29 for extrahepatic portal vein obstruction (EHPVO) and 30 for intrahepatic disease) in our centre.Results. Sclerotherapy resulted in variceal eradication in only 11.8% of the children (mean follow-up duration: 38.4 months). Variceal eradication with sclerotherapy alone was achieved in 20.7% and 3.3% of EHPVO and intrahepatic disease patients, respectively. Injection tract embolisation was successful in reducing the number of complications and re-bleeding rates. Complications that arose included: transient pyrexia (16.7%); deep oesophageal ulcers (6.7%); stricture formation (3.3%); and re-bleeding before variceal sclerosis (23%).Conclusion. Injection sclerotherapy did not eradicate oesophageal varices in most children. Injection tract embolisation by sclerosant was associated with fewer complications and reduced re-bleeding rates
Lifestyle, Fitness and Health Promotion Initiative of the University of Ilorin, Nigeria: An Educational Media Intervention
This study examined the health promotion initiative introduced by the Management of the University of Ilorin, Ngeria. In an attempt to ensure stress free academic society that would boost staff productivity and longevity, the university invested heavily on a number of lifestyle, fitness and health promotion initiatives. Descriptive research design of the survey type was adopted for this study. Staff and registered students of the University for 2010/2011 and 2011/2012 academic sessions were sampled. A total of one thousand randomly selected academic, non- academic staff and students from the twelve faculties with the exception of postgraduate students of the university participated in the study. A structured questionnaire validated and pilot tested with reliability co-efficient of 63r was used for data collection. The data collected were subjected to descriptive and inferential statistics of chi-square and Analysis of variance at 0.05 alpha level of significance. The two postulated hypotheses for the study were rejected. The result indicated a significant hyperthy and underutilization of multi-million naira fitness equipment procured for staff and students; it also revealed low turn-out at the monthly Unilorin walk a-fitness programme for staff and students of the university. The monthly health talk organized by the health education group on causes, signs and symptoms of hypertension, diabetes and other diseases also suffered from the same low turn-out of staff and students of the university among others. The authors suggested a conducive academic environment that will enable the staff to have time to take care of their health, Unilorin walk should be organized on faculty/departmental basis as a university-wide programme will not bring the desire result. More publicity should be carried out so as to boost staff and students attendance at the monthly health talk.Key words: Lifestyle; Health Promotion; Physical Fitness; Hypo-kinetics Diseases; Physical inactivit
Land use–transport interaction modeling: A review of the literature and future research directions
The aim of this review paper is to provide comprehensive and up-to-date material for both researchers and practitioners interested in land-use-transport interaction (LUTI) modeling. The paper brings together some 60 years of published research on the subject. The review discusses the dominant theoretical and conceptual propositions underpinning research in the field and the existing operational LUTI modeling frameworks as well as the modeling methodologies that have been applied over the years. On the basis of these, the paper discusses the challenges, on-going progress and future research directions around the following thematic areas: 1) the challenges imposed by disaggregation—data availability, computation time, stochastic variation and output uncertainty; 2) the challenges of and progress in integrating activity-based travel demand models into LUTI models; 3) the quest for a satisfactory measure of accessibility; and 4) progress and challenges toward integrating the environment into LUTI models
The Effect of Sympathetic Antagonists on the Antidepressant Action of Alprazolam
Alprazolam is an anti-anxiety drug shown to be effective in the treatment of depression. In this study, the effect of sympathetic receptor antagonists on alprazolam–induced antidepressant action was studied using a mouse model of forced swimming behavioral despair. The interaction of three sympathetic receptor antagonists with benzodiazepines, which may impact the clinical use of alprazolam, was also studied. Behavioral despair was examined in six groups of albino mice. Drugs were administered intraperitoneally. The control group received only a single dose of 1% Tween 80. The second group received a single dose of alprazolam, and the third group received an antagonist followed by alprazolam. The fourth group was treated with imipramine, and the fifth group received an antagonist followed by imipramine. The sixth group was treated with a single dose of an antagonist alone (atenolol, a β1-selective adrenoceptor antagonist; propranolol, a non selective β-adrenoceptor antagonist; and prazocin, an α1-adrenoceptor antagonist). Results confirmed the antidepressant action of alprazolam and imipramine. Prazocin treatment alone produced depression, but it significantly potentiated the antidepressant actions of imipramine and alprazolam. Atenolol alone produced an antidepressant effect and potentiated the antidepressant action of alprazolam. Propranolol treatment alone produced depression, and antagonized the effects of alprazolam and imipramine, even producing depression in combined treatments.In conclusion, our results reveal that alprazolam may produce antidepressant effects through the release of noradrenaline, which stimulates β2 receptors to produce an antidepressant action. Imipramine may act by activating β2 receptors by blocking or down-regulating β1 receptors
Nanotechnology in dentistry: prevention, diagnosis, and therapy
Ensanya Ali Abou Neel,1–3 Laurent Bozec,3 Roman A Perez,4,5 Hae-Won Kim,4–6 Jonathan C Knowles3,5 1Division of Biomaterials, Operative Dentistry Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 2Biomaterials Department, Faculty of Dentistry, Tanta University, Tanta, Egypt; 3UCL Eastman Dental Institute, Biomaterials and Tissue Engineering, London, UK; 4Institute of Tissue Regenerative Engineering (ITREN), 5Department of Nanobiomedical Science and BK21 Plus NBM Global Research Center for Regenerative Medicine, 6Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea Abstract: Nanotechnology has rapidly expanded into all areas of science; it offers significant alternative ways to solve scientific and medical questions and problems. In dentistry, nanotechnology has been exploited in the development of restorative materials with some significant success. This review discusses nanointerfaces that could compromise the longevity of dental restorations, and how nanotechnolgy has been employed to modify them for providing long-term successful restorations. It also focuses on some challenging areas in dentistry, eg, oral biofilm and cancers, and how nanotechnology overcomes these challenges. The recent advances in nanodentistry and innovations in oral health-related diagnostic, preventive, and therapeutic methods required to maintain and obtain perfect oral health, have been discussed. The recent advances in nanotechnology could hold promise in bringing a paradigm shift in dental field. Although there are numerous complex therapies being developed to treat many diseases, their clinical use requires careful consideration of the expense of synthesis and implementation. Keywords: nanotechnology, nanointerfaces, biofilm-related oral diseases, tissue engineering, drug delivery, toxicit
Interference suppression techniques for OPM-based MEG: Opportunities and challenges
One of the primary technical challenges facing magnetoencephalography (MEG) is that the magnitude of neuromagnetic fields is several orders of magnitude lower than interfering signals. Recently, a new type of sensor has been developed – the optically pumped magnetometer (OPM). These sensors can be placed directly on the scalp and move with the head during participant movement, making them wearable. This opens up a range of exciting experimental and clinical opportunities for OPM-based MEG experiments, including paediatric studies, and the incorporation of naturalistic movements into neuroimaging paradigms. However, OPMs face some unique challenges in terms of interference suppression, especially in situations involving mobile participants, and when OPMs are integrated with electrical equipment required for naturalistic paradigms, such as motion capture systems. Here we briefly review various hardware solutions for OPM interference suppression. We then outline several signal processing strategies aimed at increasing the signal from neuromagnetic sources. These include regression-based strategies, temporal filtering and spatial filtering approaches. The focus is on the practical application of these signal processing algorithms to OPM data. In a similar vein, we include two worked-through experiments using OPM data collected from a whole-head sensor array. These tutorial-style examples illustrate how the steps for suppressing external interference can be implemented, including the associated data and code so that researchers can try the pipelines for themselves. With the popularity of OPM-based MEG rising, there will be an increasing need to deal with interference suppression. We hope this practical paper provides a resource for OPM-based MEG researchers to build upon
Using OPMs to measure neural activity in standing, mobile participants
Optically pumped magnetometer-based magnetoencephalography (OP-MEG) can be used to measure neuromagnetic fields while participants move in a magnetically shielded room. Head movements in previous OP-MEG studies have been up to 20 cm translation and ∼30° rotation in a sitting position. While this represents a step-change over stationary MEG systems, naturalistic head movement is likely to exceed these limits, particularly when participants are standing up. In this proof-of-concept study, we sought to push the movement limits of OP-MEG even further. Using a 90 channel (45-sensor) whole-head OP-MEG system and concurrent motion capture, we recorded auditory evoked fields while participants were: (i) sitting still, (ii) standing up and still, and (iii) standing up and making large natural head movements continuously throughout the recording - maximum translation 120 cm, maximum rotation 198°. Following pre-processing, movement artefacts were substantially reduced but not eliminated. However, upon utilisation of a beamformer, the M100 event-related field localised to primary auditory regions. Furthermore, the event-related fields from auditory cortex were remarkably consistent across the three conditions. These results suggest that a wide range of movement is possible with current OP-MEG systems. This in turn underscores the exciting potential of OP-MEG for recording neural activity during naturalistic paradigms that involve movement (e.g. navigation), and for scanning populations who are difficult to study with stationary MEG (e.g. young children)
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