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71.
Next of kin play an important role in organ donation. The aim of this study was to assess the extent to which explicitness of consent to organ donation by the deceased impacts the likelihood that next of kin will agree to organ donation of the deceased by using hypothetical cases. Results indicate that that people say they are more willing to agree to donate organs of those who explicitly consented to donate than those whose permission to donate is presumed. The degree of explicitness for the consent to donate by the deceased appears to influence the next of kin's decision about whether to agree to donation. This variation might explain the absence of differences in efficiency between various types of consent systems.  相似文献   
72.
Vaginal lactobacilli assessed by PCR-based microarray and PCR-based genotyping of HPV in South African women at risk for HIV and BV. Vaginal lactobacilli can be defined by microarray techniques in fixed cervical samples of South African women. Cervical brush samples suspended in the coagulant fixative BoonFix of one hundred women attending a health centre for HIV testing in South Africa were available for this study. In the Ndlovu Medical Centre in Elandsdoorn, South Africa, identification of 18 hr-HPV genotypes was done using the INNO-LiPA method. An inventory of lactobacilli organisms was performed using microarray technology. On the basis of the Lactobacillus and Lactobacillus biofilm scoring, the cases were identified as Leiden bacterial vaginosis (BV) negative (BV-; n = 41), Leiden BV intermediate (BV±; n = 25), and Leiden BV positive (BV+; n = 34). Fifty-one women were HIV positive and 49 HIV negative. Out of the 51 HIV positive women, 35 were HPV infected. These 51 HIV positive women were frequently infected with HPV16 and HPV18. In addition, HPV35, HPV52, HPV33, and HPV66 were often detected in these samples. Lactobacillus salivarius and Lactobacillus iners were the most prevalent lactobacilli as established by the microarray technique. In women with HPV infection, the prevalence of Lactobacillus crispatus was significantly reduced. In both HIV and HPV infection, a similar (but not identical) shift in the composition of the lactobacillus flora was observed. We conclude that there is a shift in the composition of vaginal lactobacilli in HIV-infected women. Because of the prominence of HPV35, HPV52, HPV33, and HPV66, vaccination for exclusively HPV16 and HPV18 might be insufficient in South African HIV+ women.  相似文献   
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Reversal of the dopamine (DA) membrane transporter is the main mechanism through which many drugs of abuse increase DA levels. However, drug-induced modulation of exocytotic DA release by electrical (depolarization) and neurochemical inputs (e.g., acetylcholine (ACh)) may also contribute. We therefore investigated effects of methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA) and meta-chlorophenylpiperazine (mCPP) (1-1000 μM) on these inputs by measuring drug-induced changes in basal, depolarization- and ACh-evoked intracellular calcium concentrations ([Ca(2+)](i)) using a dopaminergic model (PC12 cells) and Fura 2 calcium imaging. The strongest drug-induced effects were observed on cholinergic input. At 0.1mM all drugs inhibited the ACh-evoked [Ca(2+)](i) increases by 40-75%, whereas ACh-evoked [Ca(2+)](i) increases were nearly abolished following higher drug exposure (1mM, 80-97% inhibition). Additionally, high MDMA and mCPP concentrations increased basal [Ca(2+)](i), but only following prior stimulation with ACh. Interestingly, low concentrations of methamphetamine or amphetamine (10 μM) potentiated ACh-evoked [Ca(2+)](i) increases. Depolarization-evoked [Ca(2+)](i) increases were also inhibited following exposure to high drug concentrations, although drugs were less potent on this endpoint. Our data demonstrate that at high drug concentrations all tested drugs reduce stimulation-evoked increases in [Ca(2+)](i), thereby probably reducing dopaminergic output through inhibition of electrical and cholinergic input. Furthermore, the increases in basal [Ca(2+)](i) at high concentrations of MDMA and mCPP likely increases dopaminergic output. Similarly, the increases in ACh-evoked [Ca(2+)](i) upon cholinergic stimulation following exposure to low concentrations of amphetamines can contribute to drug-induced increases in DA levels observed in vivo. Finally, this study shows that mCPP, which is regularly found in ecstasy tablets, is the most potent drug regarding the investigated endpoints.  相似文献   
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A major challenge in central nervous system (CNS) drug research is to develop a generally applicable methodology for repeated measurements of drug effects on the entire CNS, without task-related interactions and a priori models. For this reason, data-driven resting-state fMRI methods are promising for pharmacological research. This study aimed to investigate whether different psychoactive substances cause drug-specific effects in functional brain connectivity during resting-state. In this double blind placebo-controlled (double dummy) crossover study, seven resting-state fMRI scans were obtained in 12 healthy young men in three different drug sessions (placebo, morphine and alcohol; randomized). Drugs were administered intravenously based on validated pharmacokinetic protocols to minimize the inter- and intra-subject variance in plasma drug concentrations. Dual-regression was used to estimate whole-brain resting-state connectivity in relation to eight well-characterized resting-state networks, for each data set. A mixed effects analysis of drug by time interactions revealed dissociable changes in both pharmacodynamics and functional connectivity resulting from alcohol and morphine. Post hoc analysis of regions of interest revealed adaptive network interactions in relation to pharmacokinetic and pharmacodynamic curves. Our results illustrate the applicability of resting-state functional brain connectivity in CNS drug research.  相似文献   
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78.

Background

Loco-regional treatment failure after radiotherapy with or without chemotherapy and/or prior surgery represents a significant portion of head and neck cancer patients. Due to a wide array of biological interactions, these patients have a significantly increased risk of complications related to wound healing.

Methods

Review of the current literature was performed for wound healing pathophysiology, head and neck salvage surgery, and wound therapy.

Results

The biology of altered wound healing in the face of previous surgery and chemoradiotherapy is well described in the literature. This is reflected in multiple clinical studies demonstrating increased rates of wound healing complications in salvage surgery, most commonly in the context of previous irradiation. Despite these disadvantages, multiple studies have described strategies to optimize healing outcomes. The literature supports preoperative optimization of known wound healing factors, adjunctive wound care modalities, and microvascular free tissue transfer for salvage surgery defects and wounds.

Conclusion

Previously treated head and neck patients requiring salvage surgery have had a variety of disadvantages related to wound healing. Recognition and treatment of these factors can help to reverse adverse tissue conditions. A well-informed approach to salvage surgery with utilization of free vascularized or pedicled tissue transfer as well as optimizing wound healing factors is essential to obtaining favorable outcomes.  相似文献   
79.
Multiplex ligation-dependent probe amplification (MLPA) is a new assay for the detection of multiple chromosomal deletions in tumor tissue in a single experiment. Since genotyping of gliomas with oligodendroglial features by the detection of 1p/19q chromosomal deletions became essential for treatment decisions, we developed and validated an MLPA-based assay to determine these losses in formalin fixed and paraffin embedded oligodendroglial tumors (OG). Nineteen OGs, and 10 control samples were analyzed by MLPA and the results were correlated with those obtained by fluorescent in situ hybridization (FISH). The MLPA results were reproducible in all samples in which repeated experiments were performed. In 18 of 19 OGs, MLPA and FISH were concordant for presence or absence of 1p deletion. In 3 OGs, MLPA detected a 19q deletion not shown by FISH. For the other 15 OGs, MLPA and FISH were concordant. In one sample with 50% to 75% of tumor, MLPA failed to detect the 1p/19q deletions revealed by FISH (though with borderline values of significance). We conclude that MLPA is a valid and reproducible method for the detection of 1p/19q chromosomal deletions in OGs stored on formalin fixed, paraffin embedded tissue.  相似文献   
80.
Public Private Partnerships (PPPs) are multiple stakeholder partnerships designed to improve research efficacy. We focus on PPPs in the biomedical/pharmaceutical field, which emerged as a logical result of the open innovation model. Originally, a typical PPP was based on an academic and an industrial pillar, with governmental or other third party funding as an incentive. Over time, other players joined in, often health foundations, patient organizations, and regulatory scientists. This review discusses reasons for initiating a PPP, focusing on precompetitive research. It looks at typical expectations and challenges when starting such an endeavor, the characteristics of PPPs, and approaches to assessing the success of the concept. Finally, four case studies are presented, of PPPs differing in size, geographical spread, and research focus.  相似文献   
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