197 research outputs found
Effect of Different Denture Base Materials and Changed Mouth Temperature on Dimensional Stability of Complete Dentures
Background. Type of materials used in fabrication of denture base has an effect on dimension during denture base material processing and other factors related to clinical use. Objective. The study aims were to assess the dimensional stability including thermal changes of three different denture base materials. Methods. Ninety patients were selected to construct complete dentures with different denture base materials. They were randomly divided into three groups: group 1, patients with cobalt chrome metallic base; group 2, patients with heat curing acrylic resin fabricated by injection moulding technique; and group 3, patients with denture bases fabricated by conventional heat curing acrylic resin. The dimensional changes were assessed using digital caliper. Results. After the twelfth month, injection moulding acrylic resin had significantly the highest dimensional change followed by the conventional heat curing acrylic resin. There were no significant differences in the dimensions between the three types of denture base materials at normal mouth temperature, while, after hot tea drinking at 45°C, the dimensional change was significantly the highest in cobalt chrome metallic denture base group. Conclusion. Cobalt chrome metallic denture base has stable dimension compared to denture bases fabricated of acrylic resin but it was more affected by altered mouth temperature. The study was registered in the International Standard Randomized Controlled Trials Number (ISRCTN) registry with study ID (ISRCTN94238244)
Acaricidal activity of Foeniculum vulgare against Rhipicephalus annulatus is mainly dependent on its constituent from trans-anethone
Globally, the economic losses due to hard ticks infestation and the control of the associated diseases have been calculated at USD $13.9-18.7 billion per year. The economic impact is related to its direct damage to the skins, blood loss, anemia, severe immunological reactions and indirect losses that related to the effects of hemoparasites, cost of treatment for clinical cases and expenses incurred in the control of ticks. The current study evaluated the acaricidal activities of fennel Foeniculum vulgare essential oil and its main components; trans-anethole and fenchone; against R. annulatus. GC-MS analysis revealed that this oil contained 16 components representing 99.9% of the total identified compounds with E-anethole being the predominant component(64.29%), followed by fenchone (9.94%). The fennel oil and trans-anethole showed significant acaricidal activities. The LC50 of the fennel oil was attained at concentrations of 12.96% for adult ticks and 1.75% for tick larvae meanwhile the LC50 of trans-anethole was reached at concentrations of 2.36% for adult tick and 0.56% for tick larvae. On the contrary, fenchone showed no any significant adulticidal activities and its LC50 attained at a concentration of 9.11% for tick larvae. Regarding repellence activities, trans-anethole achieved 100% repellency at the concentration of 10% while fennel showed 86% repellency at the same concentration. Fenchone showed no repellency effect. Treatment of larvae with fennel, trans-anethole, and fenchone LC50 concentrations significantly inhibited the acetylcholinesterase activity. Meanwhile, glutathione s-transferase activity was significantly decreased in fennel treated larvae but no significant effect was found in the larvae of trans-anethole and fenchone groups. These results indicate that the acaricide effect of fennel oil may attributed to its high content of trans-anethole. This was supported by potent adulticidal, larvicidal, and repellency effects of trans-anethole against Rhipeciphalus annulatus tick and therefore it could be included in the list of acaricide of plant origin
Exploiting Inter- and Intra-Memory Asymmetries for Data Mapping in Hybrid Tiered-Memories
Modern computing systems are embracing hybrid memory comprising of DRAM and
non-volatile memory (NVM) to combine the best properties of both memory
technologies, achieving low latency, high reliability, and high density. A
prominent characteristic of DRAM-NVM hybrid memory is that it has NVM access
latency much higher than DRAM access latency. We call this inter-memory
asymmetry. We observe that parasitic components on a long bitline are a major
source of high latency in both DRAM and NVM, and a significant factor
contributing to high-voltage operations in NVM, which impact their reliability.
We propose an architectural change, where each long bitline in DRAM and NVM is
split into two segments by an isolation transistor. One segment can be accessed
with lower latency and operating voltage than the other. By introducing tiers,
we enable non-uniform accesses within each memory type (which we call
intra-memory asymmetry), leading to performance and reliability trade-offs in
DRAM-NVM hybrid memory. We extend existing NVM-DRAM OS in three ways. First, we
exploit both inter- and intra-memory asymmetries to allocate and migrate memory
pages between the tiers in DRAM and NVM. Second, we improve the OS's page
allocation decisions by predicting the access intensity of a newly-referenced
memory page in a program and placing it to a matching tier during its initial
allocation. This minimizes page migrations during program execution, lowering
the performance overhead. Third, we propose a solution to migrate pages between
the tiers of the same memory without transferring data over the memory channel,
minimizing channel occupancy and improving performance. Our overall approach,
which we call MNEME, to enable and exploit asymmetries in DRAM-NVM hybrid
tiered memory improves both performance and reliability for both single-core
and multi-programmed workloads.Comment: 15 pages, 29 figures, accepted at ACM SIGPLAN International Symposium
on Memory Managemen
The need for intra aortic balloon pump support following open heart surgery: risk analysis and outcome
<p>Abstract</p> <p>Background</p> <p>The early and intermediate outcome of patients requiring intraaortic balloon pump (IABP) was studied in a cohort of 2697 adult cardiac surgical patients.</p> <p>Methods</p> <p>136 patients requiring IABP (5.04%) support analysed over a 4 year period. Prospective data collection, obtained.</p> <p>Results</p> <p>The overall operative mortality was 35.3%. The "operation specific" mortality was higher on the Valve population.</p> <p>The mortality (%) as per time of balloon insertion was: Preoperative 18.2, Intraopeartive 33.3, postoperative 58.3 (p < 0.05).</p> <p>The incremental risk factors for death were: Female gender (Odds Ratio (OR) = 3.87 with Confidence Intervals (CI) = 1.3-11.6), Smoking (OR = 4.88, CI = 1.23- 19.37), Preoperative Creatinine>120 (OR = 3.3, CI = 1.14-9.7), Cross Clamp time>80 min (OR = 4.16, CI = 1.73-9.98) and IABP insertion postoperatively (OR = 19.19, CI = 3.16-116.47).</p> <p>The incremental risk factors for the development of complications were: Poor EF (OR = 3.16, CI = 0.87-11.52), Euroscore >7 (OR = 2.99, CI = 1.14-7.88), history of PVD (OR = 4.99, CI = 1.32-18.86).</p> <p>The 5 years survival was 79.2% for the CABG population and 71.5% for the valve group. (Hazard ratio = 1.78, CI = 0.92-3.46).</p> <p>Conclusions</p> <p>IABP represents a safe option of supporting the failing heart. The need for IABP especially in a high risk Valve population is associated with early unfavourable outcome, however the positive mid term results further justify its use.</p
Self-rated health, work characteristics and health related behaviours among nurses in Greece: a cross sectional study
BACKGROUND: Previous studies on self-rated health among nurses have indicated an association of low job satisfaction and stress in relation to poor self-rated health. The relationship between self rated health and the specific work characteristics and health related behaviours of nurses to our knowledge have not been adequately studied. OBJECTIVE: To investigate the health profile of nurses working in hospitals in North West Greece and to examine the associations between self rated health (SRH) and health related behaviours and work characteristics in this group of hospital employees. METHODS: A self-administered questionnaire was distributed to a random sample of 443 nurses working in all the hospitals in North West Greece. Regression analysis was used to examine the relationship of health related behaviours and work characteristics with self rated health among the nurses. RESULTS: A total of 353 responded to the questionnaire (response rate 80%) of which 311 (88%) were female and 42 (12%) male. The mean age (standard deviation) of the respondents was 36 years (5.6) and their mean years of working as nurses were 13.5 years (5.9). Almost half of the nurses' smoked, and about one third were overweight or obese. About 58% (206) of the nurses reported having poor health while 42% (147) reported having good health. Self-rated health was independently associated with gender, effort to avoid fatty foods and physical activity, according to multiple logistic regression analysis. CONCLUSION: The population studied presented a relatively poor health profile, and a high proportion of poor SRH. Though female gender and effort to avoid fatty foods were associated with poor SRH, and exercise and white meat consumption with good SRH, specific work characteristics were not associated with SRH
Lactate Dehydrogenase-B Is Silenced by Promoter Methylation in a High Frequency of Human Breast Cancers
Objective: Under normoxia, non-malignant cells rely on oxidative phosphorylation for their ATP production, whereas cancer cells rely on Glycolysis; a phenomenon known as the Warburg effect. We aimed to elucidate the mechanisms contributing to the Warburg effect in human breast cancer.
Experimental design: Lactate Dehydrogenase (LDH) isoenzymes were profiled using zymography. LDH-B subunit expression was assessed by reverse transcription PCR in cells, and by Immunohistochemistry in breast tissues. LDH-B promoter methylation was assessed by sequencing bisulfite modified DNA.
Results: Absent or decreased expression of LDH isoenzymes 1-4, were seen in T-47D and MCF7 cells. Absence of LDH-B mRNA was seen in T-47D cells, and its expression was restored following treatment with the demethylating agent 5'Azacytadine. LDH-B promoter methylation was identified in T-47D and MCF7 cells, and in 25/ 25 cases of breast cancer tissues, but not in 5/ 5 cases of normal breast tissues. Absent immuno-expression of LDH-B protein (<10% cells stained), was seen in 23/ 26 (88%) breast cancer cases, and in 4/8 cases of adjacent ductal carcinoma in situ lesions. Exposure of breast cancer cells to hypoxia (1% O2), for 48 hours resulted in significant increases in lactate levels in both MCF7 (14.0 fold, p = 0.002), and T-47D cells (2.9 fold, p = 0.009), but not in MDA-MB-436 (-0.9 fold, p = 0.229), or MCF10AT (1.2 fold, p = 0.09) cells.
Conclusions: Loss of LDH-B expression is an early and frequent event in human breast cancer occurring due to promoter methylation, and is likely to contribute to an enhanced glycolysis of cancer cells under hypoxia
Work factors and psychological distress in nurses' aides: a prospective cohort study
<p>Abstract</p> <p>Background</p> <p>Nurses' aides (assistant nurses), the main providers of practical patient care in many countries, are doing both emotional and heavy physical work, and are exposed to frequent social encounters in their job. There is scarce knowledge, though, of how working conditions are related to psychological distress in this occupational group. The aim of this study was to identify work factors that predict the level of psychological distress in nurses' aides.</p> <p>Methods</p> <p>The sample of this prospective study comprised 5076 Norwegian nurses' aides, not on leave when they completed a mailed questionnaire in 1999. Of these, 4076 (80.3 %) completed a second questionnaire 15 months later. A wide spectrum of physical, psychological, social, and organisational work factors were measured at baseline. Psychological distress (anxiety and depression) was assessed at baseline and follow-up by the SCL-5, a short version of Hopkins Symptom Checklist-25.</p> <p>Results</p> <p>In a linear regression model of the level of psychological distress at follow-up, with baseline level of psychological distress, work factors, and background factors as independent variables, work factors explained 2 % and baseline psychological distress explained 34 % of the variance. Exposures to role conflicts, exposures to threats and violence, working in apartment units for the aged, and changes in the work situation between baseline and follow-up that were reported to result in less support and encouragement were positively associated with the level of psychological distress. Working in psychiatric departments, and changes in the work situation between baseline and follow-up that gave lower work pace were negatively associated with psychological distress.</p> <p>Conclusion</p> <p>The study suggests that work factors explain only a modest part of the psychological distress in nurses' aides. Exposures to role conflicts and threats and violence at work may contribute to psychological distress in nurses' aides. It is important that protective measures against violent patients are implemented, and that occupational health officers offer victims of violence appropriate support or therapy. It is also important that health service organisations focus on reducing role conflicts, and that leaders listen to and consider the views of the staff.</p
Highly Pathogenic Avian Influenza Virus Subtype H5N1 in Africa: A Comprehensive Phylogenetic Analysis and Molecular Characterization of Isolates
Highly pathogenic avian influenza virus A/H5N1 was first officially reported in Africa in early 2006. Since the first outbreak in Nigeria, this virus spread rapidly to other African countries. From its emergence to early 2008, 11 African countries experienced A/H5N1 outbreaks in poultry and human cases were also reported in three of these countries. At present, little is known of the epidemiology and molecular evolution of A/H5N1 viruses in Africa. We have generated 494 full gene sequences from 67 African isolates and applied molecular analysis tools to a total of 1,152 A/H5N1 sequences obtained from viruses isolated in Africa, Europe and the Middle East between 2006 and early 2008. Detailed phylogenetic analyses of the 8 gene viral segments confirmed that 3 distinct sublineages were introduced, which have persisted and spread across the continent over this 2-year period. Additionally, our molecular epidemiological studies highlighted the association between genetic clustering and area of origin in a majority of cases. Molecular signatures unique to strains isolated in selected areas also gave us a clearer picture of the spread of A/H5N1 viruses across the continent. Mutations described as typical of human influenza viruses in the genes coding for internal proteins or associated with host adaptation and increased resistance to antiviral drugs have also been detected in the genes coding for transmembrane proteins. These findings raise concern for the possible human health risk presented by viruses with these genetic properties and highlight the need for increased efforts to monitor the evolution of A/H5N1 viruses across the African continent. They further stress how imperative it is to implement sustainable control strategies to improve animal and public health at a global level
Antisperm Antibody Testing: A Comprehensive Review of Its Role in the Management of Immunological Male Infertility and Results of a Global Survey of Clinical Practices
Antisperm antibodies (ASA), as a cause of male infertility, have been detected in infertile males as early as 1954. Multiple causes of ASA production have been identified, and they are due to an abnormal exposure of mature germ cells to the immune system. ASA testing (with mixed anti-globulin reaction, and immunobead binding test) was described in the WHO manual 5th edition and is most recently listed among the extended semen tests in the WHO manual 6th edition. The relationship between ASA and infertility is somewhat complex. The presence of sperm agglutination, while insufficient to diagnose immunological infertility, may indicate the presence of ASA. However, ASA can also be present in the absence of any sperm agglutination. The andrological management of ASA depends on the etiology and individual practices of clinicians. In this article, we provide a comprehensive review of the causes of ASA production, its role in immunological male infertility, clinical indications of ASA testing, and the available therapeutic options. We also provide the details of laboratory procedures for assessment of ASA together with important measures for quality control. Additionally, laboratory and clinical scenarios are presented to guide the reader in the management of ASA and immunological male infertility. Furthermore, we report the results of a recent worldwide survey, conducted to gather information about clinical practices in the management of immunological male infertility
Male oxidative stress infertility (MOSI): proposed terminology and clinical practice guidelines for management of idiopathic male infertility
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in the etiology of male infertility, with 30% to 80% of infertile men having elevated seminal reactive oxygen species levels. OS can negatively affect fertility via a number of pathways, including interference with capacitation and possible damage to sperm membrane and DNA, which may impair the sperm's potential to fertilize an egg and develop into a healthy embryo. Adequate evaluation of male reproductive potential should therefore include an assessment of sperm OS. We propose the term Male Oxidative Stress Infertility, or MOSI, as a novel descriptor for infertile men with abnormal semen characteristics and OS, including many patients who were previously classified as having idiopathic male infertility. Oxidation-reduction potential (ORP) can be a useful clinical biomarker for the classification of MOSI, as it takes into account the levels of both oxidants and reductants (antioxidants). Current treatment protocols for OS, including the use of antioxidants, are not evidence-based and have the potential for complications and increased healthcare-related expenditures. Utilizing an easy, reproducible, and cost-effective test to measure ORP may provide a more targeted, reliable approach for administering antioxidant therapy while minimizing the risk of antioxidant overdose. With the increasing awareness and understanding of MOSI as a distinct male infertility diagnosis, future research endeavors can facilitate the development of evidence-based treatments that target its underlying cause
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