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51.

Background  

The oncoprotein HER-2 is over-expressed and/or has undergone gene amplification in between 20 to 30% of breast and ovarian cancers. HER-2 amplified breast cancer is associated with a poor prognosis and increased resistance to chemo- and hormonal therapy. Data supporting the transforming potential of HER-2 are irrefutable but the mechanism by which HER-2 contributes to this process is complex and a unified model of HER2-induced increased cell proliferation and survival has not emerged.  相似文献   
52.

Objective  

This retrospective chart review describes the epidemiology and clinical features of 40 patients with culture-proven Mycoplasma pneumoniae infections at King Abdulaziz University Hospital, Jeddah, Saudi Arabia.  相似文献   
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Objective: Constipation is a common adverse effect in patients requiring long-term opioid therapy for pain control. Methylnaltrexone, a quaternary peripheral mu-opioid receptor antagonist, is an effective treatment of opioid induced constipation (OIC) without affecting centrally mediated analgesia. Our objective was to conduct a review and meta-analysis to evaluate the efficacy of methylnaltrexone for treatment of OIC, as well as to provide a clinical discussion regarding newly developed alternatives and provide the current treatment algorithm utilized at our institution.

Methods: We performed a systematic review and meta-analysis of randomized control trials using Cochrane Collaboration Databases and MEDLINE from 2007-present. Literature related to methylnaltrexone, opioids, opioid receptors, opioid antagonists, opioid-induced constipation were reviewed. A meta-analysis was completed with the primary outcome of rescue-free bowel movement (RFBM) within four hours of administration. All pooled analyses were based on random-effects models.

Results: 1239 patients were analyzed; 599 received methylnaltrexone and 640 received placebo. With a 95% CI calculated, the true risk difference is between 0.267 and 0.385, demonstrating a statistically significant difference in RFBM between treatment and placebo groups (p < 0.0001). Both the 0.15 mg/kg, 0.30 mg/kg doses every other day, and 12 mg/day dose were found to have increased risk of RFBM compared to placebo.

Conclusion: Results support the use of methylnaltrexone. Furthermore, the use of methylnaltrexone to induce laxation may decrease use of health care resources, increase work productivity, and improve cost utilization. New treatments have been made available; however, controlled clinical studies are needed to demonstrate long–term efficacy, safety and cost–effectiveness. Possible limitations of this study include the relatively small number of randomized, placebo-controlled trials investigating the efficacy of methylnaltrexone versus placebo. There is also the possibility of publication bias, which may lead to overestimating the efficacy of methylnaltrexone in treating OIC.  相似文献   

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We seek an aetiopathogenic model for the spectrum of Parkinson’s disease (PD), functional bowel disease, depression and cognitive impairment. The adopted concept is that systemic immuno-inflammatory processes mediate neuro-inflammation. The model would be based on phenotype, exposome (including gastrointestinal microbiome), milieu (immuno-inflammatory and metabolome), human genetics and their interactions. It would enable a patient’s position, to be understood in terms of drivers, perpetuators and mediators, and a future position, with and without intervention, predicted. Even the cardinal facets of PD may have different drivers: halting one may allow escape down subordinate pathways. Peptic ulceration is prodromal to PD. In our randomised placebo-controlled trial, hypokinesia improved over the year following biopsy-proven Helicobacter pylori eradication and rigidity worsened. This was independent of any (stable, long t½) antiparkinsonian medication. There are pointers to an autoimmune process: for example, surveillance-confirmed hypokinesia effect was indication specific. During surveillance, successive antimicrobial courses, other than for Helicobacter, were associated with cumulative increase in rigidity. Exhibiting laxatives appeared to stem the overall temporal increase, despite antiparkinsonian medication, in rigidity. Thus, intestinal dysbiosis may be a major source of bystander neuronal damage. There are biological gradients of objective measures of PD facets on circulating inflammatory markers and leucocyte subset counts. Moreover, lactulose hydrogen breath test positivity for small-intestinal bacterial overgrowth (present in two thirds of PD patients) is associated with the same subsets: higher natural killer and total CD4+ counts and lower neutrophils. With greater aetiopathogenic understanding, relatively low cost and on-the-shelf medication could have a major impact. A new generation of animal models, based on the gut microbiome, is envisaged.  相似文献   
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Leptospirosis is a zoonosis of worldwide distribution, caused by infection with pathogenic Leptospira species. The vaccines that are currently available are bacterins, with limited human use, that confer short-term, serovar-specific immunity. Lig proteins are considered to be the best vaccine candidates to date. Here, we aimed to construct a recombinant Lig chimera (LC) comprised of LigAni and LigBrep fragments, and to evaluate it as subunit or DNA vaccine using different administration strategies. Vaccines were formulated with 50?µg of recombinant LC associated with different adjuvants or with 100?µg of pTARGET/LC. Four-week-old hamsters received two doses of vaccine with different strategies and were challenged with 5?×?DL50 Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. The immune response generated by Lig chimera conferred 100% protection to hamsters treated with at least one dose of recombinant LC. Despite the high levels of antibodies that vaccinated animals produced, a sterilizing immunity was not achieved. The lack of a sterilizing immunity could indicate the importance of a mixed humoral and cellular immune response. The present study generated insights that will be useful in the future development of improved subunit vaccines against leptospirosis.  相似文献   
59.
The aim of this research was to study the relationship between personality dimensions, positive emotions and coping mechanisms of caregivers of patients living with HIV. This study used a cross‐sectional research design. A sample comprising 56 caregivers was recruited from HIV/AIDS clinics in three teaching hospitals in Lahore, Pakistan. Data were collected between February and July 2010. Most caregivers were men, and of low socio‐economic status. Individuals with both high and low extraversion used problem‐focused coping, self‐control and accepting responsibility, but those with low extraversion used more escape‐avoidance coping, and they had also high levels of negative emotions. Those high in neuroticism used more tension‐reduction coping than problem‐focused coping, and experienced fewer positive emotions. Regression analysis findings revealed neuroticism as a significant predictor of negative emotions as well as emotion‐focused coping, and only extraversion significantly predicted negative emotions. This research could help in devising psychological management plans for caregivers of patients living with HIV in order to assist them in coping with the burden of care.  相似文献   
60.
Chronic lymphocytic leukemia (CLL) is an archetype of malignancy resulting from defects in apoptosis. CLL is an exclusive accumulative disorder marked by low proliferative activity and gradual accumulation of clonal B-lymphocytes blocked in the early (G0, G1) phases of the cell cycle. The heterogeneous clinical course indicates diverse in vivo biology of the leukemic cell and suggests that CLL represents diverse behavior. Understanding the molecular biology of the disease has provided insight into the mechanisms that promote tumorigenesis, specifically defective apoptotic signaling pathways. In this review we attempt to provide a comprehensive discussion of CLL including the origin of malignant lymphocytes, the apoptotic defects and the mechanisms leading to disease progression. We further discuss the therapeutic options, focusing mainly on targeted therapy using novel agents. Finally, we suggest future directions for treatment that utilize the understanding of the disease biology.  相似文献   
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