Interaction of cyclin-dependent kinase 2 and the Lyn tyrosine kinase in cells treated with 1-beta-D-arabinofuranosylcytosine

The cyclin dependent kinase 2 (Cdk2) is required for initiation and progression of DNA replication. Activation of Cdk2 involves binding to cyclin E or cyclin A and dephosphorylation of Tyr15. The present studies demonstrate that treatment of U-937 cells with 1-beta-D-arabinofuranosylcytosine (ara-C) is associated with tyrosine phosphorylation of Cdk2 and inhibition of Cdk2 activity. The results also demonstrate that Cdk2 directly associates with the Src-like tyrosine kinase Lyn as a consequence of ara-C-treatment. Confocal microscopy studies show that Lyn is detectable in the nucleus and that it colocalises with Cdk2. Subcellular fractionation and coimmunoprecipitation studies further demonstrate nuclear binding of Lyn and Cdk2. We also show that Lyn phosphorylates Tyr15 of Cdk2 and that incubation of Lyn with Cdk2 results in inhibition of Cdk2 activity. These findings suggest that the association of Lyn and Cdk2 in ara-C-treated cells may contribute to regulation of Cdk2-dependent cell cycle checkpoints.     

Effect of multiple coil closure of patent ductus arteriosus on blood flow to the left lung as determined by lung perfusion scans

This paper describes a combined inpatient and partial hospital program, with a ten-bed short-term inpatient unit and a partial hospital program that can accommodate 24 patients. Inpatients and partial hospital patients are treated together by the same staff in a program located in the partial hospital. The authors highlight features of the program that address the five elements of continuity: place, personnel, program, patient-peers, and plan for treatment. The discussion focuses on the importance of continuity in sustaining a combined unit; potential benefits for patients, families, staff, and trainees; attractiveness to third-party payers; and impediments to fully realizing the potential of the unit.     

Serum interleukin-1beta, interleukin-6, nitric oxide and alpha1-antitrypsin in scorpion envenomed children

During the present study, thirty-eight children in Upper Egypt (less than 12years old) were admitted to Pediatric Intensive Care Unit for scorpion envenomation. They were compared with thirteen apparently healthy children of matching age as controls. The victims and controls were subjected to complete clinical examination and full blood count. The evaluations of the serum levels of interleukin-1beta (IL-1beta), interleukin-6 (IL-6), nitric oxide (NO) and alpha1-antitrypsin (alpha1-AT) were performed once for the controls and twice for the victims, the first sample on admission and the 2nd sample after 24 h. All victims showed significantly higher mean values of IL-1beta IL-6, NO, alpha1-AT and leucocytic count both on admission and on follow up when compared with controls. Manifestations of mild envenomation were detected among 28.9% of the victims, while 71.1% of the victims manifested severe scorpion envenomation. The severely envenomated children showed significantly higher mean values of IL-1beta, IL-6, NO, alpha1-AT and leucocytic count both on admission and on follow up when compared with mild cases. The case fatality rate in the current study was 7.8%. The non-surviving victims showed significantly higher mean values of IL-1beta, IL-6 and leucocytic count both on admission and on follow up in comparison to the survivors. Furthermore, those fatal cases showed a non-significant decline in the studied biochemical indices on follow up after 24 h, while the survivors showed a significant decline in the serum levels of IL-6, IL-1beta, NO and alpha1-AT after 24h of post arrival to the hospital. In conclusion, these data revealed that cytokines are involved in the pathogenesis of scorpion envenomation and correlated with the severity of envenomation. This may provide a rationale for anticytokine treatment.     

钟摆钻具扶正器安放高度计算

钟摆钻具是一种常用的纠斜钻具组合,在钻井中应用极为广泛。文中对石油工业部１９８７年颁布的“直井部钻具组合设计推荐方法”中的钟摆钻具扶正器理想安放高度计算公式进行了推导,对公式的简化,和学模型进行了分析,并结合实例探讨了该公式的实际应用价值。这对进一步理解钟摆具扶正器理想安放高度的设计方法和指导现场应用具有一定的参考价值。     

Recent Advances on the Role of Brain-Derived Neurotrophic Factor (BDNF) in Neurodegenerative Diseases

Neurotrophins, such as brain-derived neurotrophic factor (BDNF), are essential for neuronal survival and growth. The signaling cascades initiated by BDNF and its receptor are the key regulators of synaptic plasticity, which plays important role in learning and memory formation. Changes in BDNF levels and signaling pathways have been identified in several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease, and have been linked with the symptoms and course of these diseases. This review summarizes the current understanding of the role of BDNF in several neurodegenerative diseases, as well as the underlying molecular mechanism. The therapeutic potential of BDNF treatment is also discussed, in the hope of discovering new avenues for the treatment of neurodegenerative diseases.     

Effect of operating parameters and chemical treatment on the tribological performance of natural fiber composites: A review

The demand for high-performance engineering products made from natural resources is increasing because of the low-cost, low-density, biodegradability, renewable nature and lighter than synthetic fibers. With these characteristics, the tribological performance of natural fiber composite has become an important element to be considered in most industrial and manufacturing functions. This paper presents an overview of the factors that influence the tribological performance of natural fiber composites, which include applied load, sliding distance, sliding velocity and fiber orientation. Influences of chemical treatment is also reviewed and illustrated through scanning electron microscope (SEM) observations. This review will focus on kenaf fibers (KFs) and oil palm fibers (OPFs) which have been widely exploited over the past few years among the available natural resources. The results show that the operating parameter, fiber orientation and chemical treatment has significant effects on the tribological performance of natural composite. A clear understanding of the factors that affect the tribological performance is very essential in performance improvement on natural fibers reinforced polymer composite for potential applications.     

Genetic and antigenic analysis of human rotavirus prevalent in Al-Taif, Saudi Arabia

The subgroup, serotype and electropherotype diversity of human rotavirus strains was investigated in Al-Taif, Saudi Arabia. Out of 349 faecal samples collected from diarrhoeic children, 150 (43 percent) tested rotavirus positive by a group-A specific enzyme-linked immunosorbent assay (ELISA). The majority (87 percent) of the infected children were below 2 years of age. Subgrouping and serotyping of rotaviruses with specific monoclonal antibodies showed that of the 150 rotavirus positive specimens, 17 percent belonged to subgroup I, 59 per cent belonged to subgroup II, and 24 percent were neither subgroup I nor subgroup II. The specimens were typed, as serotype 1 (43 percent), serotype 2 (5 percent), serotype 3 (11 percent), serotype 4 (10 percent) or mixed serotypes (3 percent). The remaining 41 (27 percent) specimens were untypeable. None of the serotypes showed association with a particular age group. An electrophoretic analysis of viral RNA revealed 11 distinct patterns (six long and five short). The majority, 78 percent were long patterns and 22 percent were short patterns. Analysis of the specimens for which subgroups, serotypes and electropherotypes were available indicated that a given RNA pattern does not correspond to a particular subgroup or serotype.     

Health status and quality of life following cardiac transplantation

There is little information regarding the functional status and quality of life of cardiac transplant patients. This investigation is the largest study describing outcome up to 10 years after cardiac transplantation. We conducted a cross-sectional survey of 200 cardiac transplant recipients using the Sickness Impact Profile and a supplementary questionnaire. The response rate was 48%. The median duration post-cardiac transplantation was 2.3 years (range, 0.5 to 9.7 years). The median age was 53 years (range, 27.1 to 68.7). In comparison to previously published studies, our sample of cardiac transplant recipients had worse quality of life than normals, similar scores to cardiac arrest survivors and post-myocardial infarction patients, and better quality of life than patients with low back pain. We found that those not working (44%) reported a lower quality of life. Musculoskeletal-neurologic complaints were highly prevalent, with generalized weakness in 54% responding, fatigue in 42%, and low back pain in 37%. Lower quality of life was found in patients reporting a higher number of musculoskeletal-neurological disorders. We conclude that there are specific areas for rehabilitation intervention in patients post-cardiac transplantation, and suggest areas for future research directed towards enhancing quality of life for cardiac transplant recipients.