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681.
Tumour vascularization: sprouting angiogenesis and beyond   总被引:11,自引:0,他引:11  
Tumour angiogenesis is a fast growing domain in tumour biology. Many growth factors and mechanisms have been unravelled. For almost 30 years, the sprouting of new vessels out of existing ones was considered as an exclusive way of tumour vascularisation. However, over the last years several additional mechanisms have been identified. With the discovery of the contribution of intussusceptive angiogenesis, recruitment of endothelial progenitor cells, vessel co-option, vasculogenic mimicry and lymphangiogenesis to tumour growth, anti-tumour targeting strategies will be more complex than initially thought. This review highlights these processes and intervention as a potential application in cancer therapy. It is concluded that future anti-vascular therapies might be most beneficial when based on multimodal anti-angiogenic, anti-vasculogenic mimicry and anti-lymphangiogenic strategies.  相似文献   
682.
OBJECTIVE: To review the literature describing the content and time allocated to undergraduate medical education curricula in child and adolescent psychiatry and make recommendations about child and adolescent psychiatry teaching goals and curricula content. METHOD: A literature search from 1970 to February 2007 using the key words undergraduate, curriculum, teaching, education, psychiatry, child, adolescent, and medical school, was conducted using PubMed, PsycINFO, and Web of Science. RESULTS: There is limited agreement about curricula content for undergraduate child and adolescent psychiatry teaching programs in medical schools, with a wide range of objectives identified by different programs. On average, the time allowed for teaching child and adolescent psychiatry is small. There is also great variation in the time allocated by different medical schools. In many countries, the number of child and adolescent psychiatrists with academic appointments is limited, and child and adolescent psychiatry programs are developed and taught by a small number of teaching staff at each medical school. CONCLUSIONS: Medical schools should reconsider the relatively low priority given to teaching child and adolescent psychiatry to medical students. The child and adolescent psychiatry profession must identify clear learning goals for a longitudinal developmentally appropriate model of child and adolescent psychiatry education commencing at an undergraduate level in medical schools and continuing through residency and fellowships. There is a need to promote national and international standards for teaching in this area and to encourage stronger collaborations between teaching staff across different medical schools.  相似文献   
683.
Fragile X syndrome is a common inherited form of mental retardation and originates from the absence of expression of the FMR1 gene. This gene and its two homologues, FXR1 and FXR2, encode for a family of fragile X related (FXR) proteins with similar tissue distribution, together with sequence and functional homology. Based on these characteristics, it has been suggested that these proteins might partly complement one another. To unravel the function of Fxr2 protein, the expression pattern of 12,588 genes was studied in the brains of wild-type and Fxr2 knockout mice, an animal model which shows behavioral abnormalities partly similar to those observed in Fmr1-knockout mice. By genome expression profiling and stringent significance tests we identify genes and gene groups de-regulated in the brains of Fxr2 knockout mice. Differential expression of candidate genes was validated by real-time PCR, in situ hybridization, immunohistochemistry and western blot analysis. A number of differentially expressed genes associated with the Fxr2 phenotype have been previously involved in other memory or cognitive disorders.  相似文献   
684.
Phthalocyanines (Pcs) are a class of photosensitizers (PSs) with a strong tendency to aggregate in aqueous environment, which has a negative influence on their photosensitizing ability in photodynamic therapy. Pcs with either peripheral or axial solketal substituents, that is, ZnPc(sol)8 and Si(sol)2Pc, respectively, were synthesized and their tendency to aggregate as well as their photodynamic properties in 14C and B16F10 cell lines were evaluated. The results were compared to more hydrophilic silicon Pcs, that is, Si(PEG750)2Pc and Pc4. The order of cellular uptake was Pc4 > ZnPc(sol)8 > Si(PEG750)2Pc > Si(sol2)Pc. In contrast, Si(sol2)Pc showed the highest photocytotoxicity, while ZnPc(sol)8 did not show any photocytotoxicity up to a concentration of 10 microM in both cell types. UV/vis spectroscopy showed that Si(sol)2Pc is less prone to aggregation than ZnPc(sol)8, which can explain the lack of photoactivity of the latter. Si(sol)2Pc was predominantly located in lipid droplets, whereas Si(PEG750)2Pc was homogeneously distributed in the cytosol, which is probably the main cause of their difference in photoactivity. The very high photodynamic efficacy of Si(sol)2Pc makes this PS an interesting candidate for future studies.  相似文献   
685.
Aims and objectives. (1) To analyse and compare (changes and differences in) activity profiles of various types of nursing home care. (2) To assess the impact of integrated care on these activity profiles. Background. Because of an ongoing introduction of integrated nursing home care, caregivers increasingly have to co‐ordinate their activities, engage into interprofessional relationships and take over each other's tasks. Consequently, activity profiles [i.e. combinations of (contributions to) care activities and the roles that perform them] are expected to change. Design/methods. At three measurement points in the period 1999–2003, caregivers (in 18 different roles) recorded and listed direct and indirect care activities. A total of 41 335 lists were analysed to derive activity profiles of traditional, transitional and integrated nursing home care in the Netherlands. Results. Traditional, transitional and integrated care shared some comparable activity profiles. Integrated care differed from the other types with respect to the contribution of the geriatric nurse, recreational activities supervisor, nutrition assistant, household assistant and nursing assistant to activities such as extra care, handling food and club activities. Contrary to the other roles, the licensed practical nurse contributed to (almost) all activities in all types of care. Conclusions. Nursing home care has several recurring activity profiles. These profiles are the same in all types of nursing home care. The introduction of integrated care implies that particular profiles have to be added to these profiles. As a generalist, the licensed practical nurse seems to play a key role in all activity profiles. Relevance to clinical practice. Because of demographic and financial pressures, integrated care for older people becomes increasingly important. By addressing the impact of integrated care on activity profiles, this paper provides information on how new types of care can be delivered in the most effective manner.  相似文献   
686.
Acute gastroenteritis is common in childhood. The estimation of the degree of dehydration is essential for management of acute gastroenteritis. Plasma water was assessed as a diagnostic tool in children with acute gastroenteritis and dehydration admitted to hospital. In a prospective cohort study, 101 patients presenting at the emergency department with dehydration were included. Clinical assessment, routine laboratory tests, and plasma water measurement were performed. Plasma water was measured as a percentage of water content using dry weight method. During admission, patients were rehydrated in 12 h. Weight gain at the end of the rehydration period and 2 weeks thereafter was used to determine the percentage of weight loss as a gold standard for the severity of dehydration. Clinical assessment of dehydration was not significantly associated with the percentage of weight loss. Blood urea nitrogen (r = 0.3, p = 0.03), base excess (r =−0.31, p = 0.03), and serum bicarbonate (r = 0.32, p = 0.02) were significantly correlated with the percentage of weight loss. Plasma water did not correlate with the percentage of weight loss. On the basis of the presented data, plasma water should not be used as a diagnostic tool in the assessment of dehydration in children with acute gastroenteritis.  相似文献   
687.
688.
Psychoneurological symptoms are commonly reported by newly diagnosed head and neck cancer (HNC) patients, yet there is limited research on the associations of these symptoms with biomarkers of stress and inflammation. In this article, pre-treatment data of a multi-center cohort of HNC patients were analyzed using a network analysis to examine connections between symptoms (poor sleep quality, anxiety, depression, fatigue, and oral pain), biomarkers of stress (diurnal cortisol slope), inflammation markers (c-reactive protein [CRP], interleukin [IL]-6, IL-10, and tumor necrosis factor alpha [TNF-α]), and covariates (age and body mass index [BMI]). Three centrality indices were calculated: degree (number of connections), closeness (proximity of a variable to other variables), and betweenness (based on the number of times a variable is located on the shortest path between any pair of other variables). In a sample of 264 patients, poor sleep quality and fatigue had the highest degree index; fatigue and CRP had the highest closeness index; and IL-6 had the highest betweenness index. The model yielded two clusters: a symptoms—cortisol slope—CRP cluster and a IL-6—IL-10—TNF-α—age—BMI cluster. Both clusters were connected most prominently via IL-6. Our findings provide evidence that poor sleep quality, fatigue, CRP, and IL-6 play an important role in the interconnections between psychoneurological symptoms and biomarkers of stress and inflammation in newly diagnosed HNC patients.  相似文献   
689.

Background

Gait deficits in people with Parkinson's disease (PD) are triggered by circumstances requiring gait adaptation. The effects of gait adaptation training on a split-belt treadmill (SBT) are unknown in PD.

Objective

We investigated the effects of repeated SBT versus tied-belt treadmill (TBT) training on retention and automaticity of gait adaptation and its transfer to over-ground walking and turning.

Methods

We recruited 52 individuals with PD, of whom 22 were freezers, in a multi-center randomized single-blind controlled study. Training consisted of 4 weeks of supervised treadmill training delivered three times per week. Tests were conducted pre- and post-training and at 4-weeks follow-up. Turning (primary outcome) and gait were assessed over-ground and during a gait adaptation protocol on the treadmill. All tasks were performed with and without a cognitive task.

Results

We found that SBT-training improved gait adaptation with moderate to large effects sizes (P < 0.02) compared to TBT, effects that were sustained at follow-up and during dual tasking. However, better gait adaptation did not transfer to over-ground turning speed. In both SBT- and TBT-arms, over-ground walking and Movement Disorder Society-Unified Parkinson's Disease Rating Scale III (MDS-UPDRS-III scores were improved, the latter of which reached clinically meaningful effects in the SBT-group only. No impact was found on freezing of gait.

Conclusion

People with PD are able to learn and retain the ability to overcome asymmetric gait-speed perturbations on a treadmill remarkably well, but seem unable to generalize these skills to asymmetric gait off-treadmill. Future study is warranted into gait adaptation training to boost the transfer of complex walking skills. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.  相似文献   
690.
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