Chymotrypsin gene expression in rat peripheral organs

Cdc25, the dual-specificity phosphatase that dephosphorylates the Cdc2-cyclin B complex at mitosis, is highly regulated during the cell cycle. In Xenopus egg extracts, Cdc25 is associated with two isoforms of the 14-3-3 protein. Cdc25 is complexed primarily with 14-3-3epsilon and to a lesser extent with 14-3-3zeta. The association of these 14-3-3 proteins with Cdc25 varies dramatically during the cell cycle: binding is high during interphase but virtually absent at mitosis. Interaction with 14-3-3 is mediated by phosphorylation of Xenopus Cdc25 at Ser-287, which resides in a consensus 14-3-3 binding site. Recombinant Cdc25 with a point mutation at this residue (Cdc25-S287A) is incapable of binding to 14-3-3. Addition of the Cdc25-S287A mutant to Xenopus egg extracts accelerates mitosis and overrides checkpoint-mediated arrests of mitotic entry due to the presence of unreplicated and damaged DNA. These findings indicate that 14-3-3 proteins act as negative regulators of Cdc25 in controlling the G2-M transition.     

Molecular mechanisms of rat and human pancreatic triglyceride lipases

Extracorporeal photochemotherapy (ExP) is a well-tolerated new form of chemoimmunotherapy, which is considered to be effective for cutaneous T-cell lymphoma (CTCL) and the treatment of choice for Sézary syndrome. Improvements have also been seen in patients with non-erythrodermic mycosis fungoides (MF) in the early stages, even when tumour cells are not detectable in the peripheral blood. In this study, we used ExP as a monotherapy in seven patients who had early stage (Ib) MF, and who were no longer responsive to or had contraindications for other therapies. We observed a clinical improvement in the disease after 12 months of treatment: one patient showed a complete response, five a partial response, and one remained stable. In each patient we compared skin biopsies of large plaque lesions before and after the treatment. We undertook a histological evaluation of the infiltrate. The lymphoid cell proliferation and death rates were quantified using the following parameters; lymphoid cell density (LCD), Ki67 + lymphoid cell nuclei percentage (Ki67 + Lcn percentage), and apoptotic index (AI). Significant decreases in the lymphoid cell infiltrate and in cell proliferation, and a significant increase in AI were observed after therapy. The mean LCD decreased from 187 +/- 33 to 34 +/- 17.7, Ki67 + Lcn mean percentage decreased from 16.9 +/- 3.9 to 4.9 +/- 2.4, and the AI mean value increased from 0.05 +/- 0.03 to 2.41 +/- 1.54. Our results suggest a role for apoptosis in the improvement of the skin lesions and are in line with some reports on the mode of action of ExP. Although the way in which ExP works needs to be clarified further, it does seem to stimulate a CD8+ cell-mediated anticlonotypic activity against circulating pathogenic clones. Furthermore, a release of tumour necrosis factor alpha (TNF-alpha) by circulating monocytes has been demonstrated after ExP. Both are known to induce cell death by apoptosis.     

Risk factors for the spine: nursing assessment and care

The present work aimed at studying risk factor that affect people with back pain, identifying them and implementing an intervention proposal of a health education program based on self-care teaching, existential humanist philosophical projects and stress equalization approach line, skeletal-muscle reintegration activities, basic techniques on stress equalization and massage. It has been developed for a population of 42 (forty-two) clients. Two instruments which integrate nursing consultation protocol have been used in data collection. The results showed the existence of associated risk factors which are changeable according to health education programs. The assessment process has contributed for therapeutic measures focus, using non-conventional care methods for this approach providing an improvement to these clients life quality.     

Intracellular calcium responses of circadian pacemaker neurons measured with fura-2

The circadian pacemaker in the eye of the mollusk Bulla gouldiana is located within basal retinal neurons (BRNs) that express a circadian rhythm in cell culture. Light and other depolarizing stimuli shift the phase of the pacemaker in the eye through a process that requires extracellular calcium and is blocked by Ni2+. To test directly if an influx of Ca2+ is present throughout depolarizing treatments that produce phase shifts, dissociated BRNs in cell culture were loaded with a membrane-permeable form of the calcium-sensitive dye fura-2, and then depolarized with elevated levels of extracellular K+. Calcium levels in the BRNs remained elevated during treatments with 50 mM K+ lasting 1 h, a sufficient duration to phase shift the circadian pacemaker. Lowering extracellular free Ca2+ (approx. 1.7 x 10(-7) M) during depolarization blocked the rise in intracellular Ca2+, verifying that a Ca2+ influx is required. The sustained Ca2+ elevation during depolarization was also prevented with 50 mM Ni2+, which blocks phase shifts of the rhythm to depolarization, but not with 5 mM Ni2+, which does not block phase shifts. The initial rise in [Ca2+]i in response to 50 mM K+ was largest on average during the subjective night. The results show that a critical portion of the entrainment pathway persists in pacemaker neurons during cell culture, and that the phase-shifting stimulus may depend on a prolonged Ca2+ signal.     

Hepatitis C virus in multiple episodes of acute hepatitis in polytransfused thalassaemic children

We investigated the course of distinct episodes of acute non-A, non-B (NANB) hepatitis in three polytransfused thalassaemic children. In each case, the first episode was associated with the appearance of serum hepatitis C virus (HCV) RNA and anti-HCV seroconversion. The second episode was accompanied by the reappearance of HCV viraemia, which in two patients was due to reinfection with a different HCV strain and in the third could be the result of either reactivation of primary infection or reinfection with a new but closely related strain. Thus HCV infection may not induce protective immunity, which has implications for vaccine development.     

无线传感器网络一种改进的随机密钥预分配方案

为解决基本的随机密钥预分配方案连通率较低的问题,提出了一种无线传感器网络的密钥管理改进方案.通过执行一个"邻居"节点扩展协议,使安全孤立节点与一跳以外的节点进行共享密钥发现,从而找到至少一条安全路径来保证网络的安全连通.对改进方案和原有方案在全局连通率、安全性和能量消耗等方面性能的分析与仿真结果比较,表明密钥管理的改进方案以有限的额外密钥协商开销为代价,能换来网络全局安全连通率、可用节点总能量和安全性能的提高.