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Background  

Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Updated data on drug-resistance from different populations may be important to recognize changes in disease patterns. This study assessed current levels of penicilin resistance among Streptococcus Pneumoniae causing pneumonia in Spanish middle age and older adults.  相似文献   
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Ocotea quixos essential oil was shown to possess significant inhibitory activity of platelet aggregation and clot retraction in rodent plasma. This study is aimed at fully characterizing the antiplatelet activity of the whole essential oil and its main components trans-cinnamaldehyde and methyl cinnamate also in human plasma, at investigating the mechanism underlying such activity and at evaluating the potential antithrombotic activity of subacute treatment of mice with Ocotea essential oil. In vitro Ocotea essential oil and trans-cinnamaldehyde inhibited arachidonic acid-, U46619-, ADP-, phorbol12-myristate13-alcetate-, collagen-induced platelet aggregation and thrombin-induced clot retraction in human and rodent plasma; Ocotea oil and trans-cinnamaldehyde competitively antagonized contractions induced by thromboxane A2 receptor agonist U46619 in rat isolated aortic ring (K(B) = 18 and 3.2 microg ml(-1), respectively). In vivo Ocotea oil, orally administered in a subacute treatment (30-100 mg kg(-1) day(-1) for 5 days) to mice, prevented acute thrombosis induced by collagen-epinephrine intravenous injection. This antithrombotic activity was not accompanied by pro-haemorragic side effect, as detected by the inactivity in bleeding test, thus showing a favourable safety profile compared to the conventional antiplatelet agent, acetylsalicylic acid. Present findings indicate that Ocotea essential oil possesses potent and safe antithrombotic activity attributable to its antiplatelet and vasorelaxant effects. The main constituent trans-cinnamaldehyde seems to be the primary responsible for this activity through a putative mechanism involving the inhibition of thromboxane A2 receptors.  相似文献   
4.
Six different types of alginates used to encapsulate Lagenidium giganteum gave similar levels of fungal infection in Culex quinquefasciatus larvae. Initial infection levels when the capsules were immersed in water after 6 days of storage (15 and 25 degrees C) were 100% for all types of alginate and after 42 days of storage was 62-100%, depending on the type of alginate. Infectivity was 24-100% after the encapsulated fungus were left in water for 7 days and after 15 days was 0 to 26%, depending on the alginate. When 2 of the alginates were tested at different concentrations to give high, medium and low viscosity solutions, the fungus encapsulated using lower concentration alginate solutions usually gave the highest level of infectivity.  相似文献   
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Cables, a cyclin-dependent kinase (cdk) interacting protein, has recently been identified and mapped to human chromosome 18q11. Cables appears to be primarily involved in cell cycle regulation and cell proliferation. Overexpression of Cables in Hela and other cell lines inhibits cell proliferation and tumor formation. We hypothesize that loss of Cables expression is associated with ovarian cancer. To test our hypothesis, we examined Cables expression in the four most common subtypes of ovarian carcinomas: serous, endometrioid, mucinous, and clear cell. In addition, mucinous and serous borderline tumors were also included. Loss of Cables expression was observed at high frequency in ovarian serous (11 of 14 cases, 79%) and endometrioid (5 of 10 cases, 50%) carcinomas. In contrast, strong Cables staining was detected in all clear cell carcinomas (10 cases) and mucinous tumors (5 carcinomas and 5 borderline tumors). The majority of serous borderline tumors (11 of 14 cases, 79%) showed positive Cables staining, with the rest showing focal loss of Cables expression. Furthermore, RT-PCR revealed the lack of Cables mRNA in a human ovarian cancer xenograft. No correlation was noted between loss of Cables and histologic grade, tumor stage, and survival. In conclusion, our results indicate that loss of Cables is common in ovarian serous and endometrioid carcinomas and imply that Cables may be involved in the pathogenesis of these two types of ovarian carcinomas.  相似文献   
7.
The data presented extend to a larger series of 27 consecutive renal allograft recipients treated prophylactically with OKT3 our previous observation that the acute OKT3-induced clinical syndrome is related to massive release in the circulation of some cytokines, among which are tumor necrosis factor and interferon gamma. In addition, a pilot randomized study was set up including 12 consecutive patients receiving high-dose corticosteroid treatment (0.5 g solumedrol) either before or at the same time as the first OKT3 injection. Results confirm that when corticosteroids are given in sufficient amount and, importantly, 1 hr before the first OKT3 injection, they significantly decrease the release of both tumor necrosis factor and interferon gamma. In addition, the pretreatment with corticosteroids may totally abolish the IL-2 release induced by OKT3. Given the key role the massive although transient cytokine release plays in determining the OKT3-induced acute syndrome, these results provide the biological basis supporting a precise kinetics of administration of high-dose corticosteroids to better decrease the severity of the clinical reaction.  相似文献   
8.
Follicular lymphoma (FL) is the second most common subtype of non-Hodgkin’s lymphoma (NHL) in the Western world. FL constitutes the most frequent indolent lymphoma, well characterized by its clinical presentation related to nodal involvement and its morphologic and biologic features. It is often managed as an incurable disease. However, several active therapeutic approaches from the ‘wait and watch” strategy to the allogeneic transplantation are available for management of patients with FL and clearly have changed the natural history of this disease, achieving a long-term disease-free survival. Therapeutic decision is mostly conditioned by patient’s characteristics, stage, histological grade, tumor burden, and risk-predicting factors. This article try to summarizes the diagnosis and treatment of this heterogeneous group of patients.  相似文献   
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OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.  相似文献   
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