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41.
Skin equivalents are increasingly used as human‐based test systems for basic and preclinical research. Most of the established skin equivalents are composed of primary keratinocytes and fibroblasts, isolated either from excised human skin or juvenile foreskin following circumcisions. Although the potential of hair follicle‐derived cells for the generation of skin equivalents has been shown, this approach normally requires microdissections from the scalp for which there is limited subject compliance or ethical approval. In the present study, we report a novel method to isolate and cultivate keratinocytes and fibroblasts from plucked hair follicles that were then used to generate skin equivalents. The procedure is non‐invasive, inflicts little‐pain, and may allow easy access to patient‐derived cells without taking punch biopsies. Overall, minor differences in morphology, ultrastructure, expression of important structural proteins, or barrier function were observed between skin equivalents generated from hair follicle‐derived or interfollicular keratinocytes and fibroblasts. Interestingly, improved basal lamina formation was seen in the hair follicle‐derived skin equivalents. The presented method here allows easy and non‐invasive access to keratinocytes and fibroblasts from plucked hair follicles that may be useful particularly for the generation of skin disease equivalents.  相似文献   
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Objectives

To investigate how a virtual cultural simulation experience and guided reflection influenced physiotherapy students’ intrapersonal and interpersonal cultural empathy, and to explore students’ satisfaction with the learning experience.

Design

Three research arms within a single cohort: 1) pre-test post-test investigation of intrapersonal cultural empathy; 2) quasi-experimental investigation of interpersonal cultural empathy; 3) post-test measurement of satisfaction.

Setting

An Australian university.

Participants

Bachelor and Master physiotherapy students, response rate 98% (162/165).

Interventions

A self-directed online virtual simulation in which the student assumed the role of a patient who has been hospitalised in a developing country. Students were then guided to reflect on the experience via online questions.

Main outcome measures

The primary measure was the Comprehensive State Empathy Scale (CSES) of intrapersonal cultural empathy. Secondary measures were the Theory of Planned Behaviour:Cultural Competence Questionnaire (TPB:CCQ) of interpersonal cultural empathy; and the Satisfaction with Cultural Simulation Experience Scale (SCSES).

Results

Intrapersonal cultural empathy improved after the virtual simulation, shown in overall CSES scores [pre-test: 95 (81–109) vs post-test: 106 (89–117); median difference 11; P = <0.001]. For the TPB:CCQ, the post-simulation (‘intervention’) group demonstrated greater ‘Perceived Behavioural Control’ interpersonal empathy compared to the presimulation (‘control’) group [4.41 (0.54) vs 4.59 (0.53); mean difference = 0.19; 95% confidence interval = 0.01 to 0.36; P = 0.020]. Satisfaction with the experience was high (mean SCSES score = 40/56 (71%)).

Conclusions

A virtual cultural simulation experience and guided reflection led to significant increases in students’ intrapersonal cultural empathy, with some influence on interpersonal cultural empathy. Students were highly satisfied with this learning experience.  相似文献   
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Abstract

Objectives: Interpretation of MRI/MRCP in primary sclerosing cholangitis (PSC) at a single time point has low inter-reader agreement. Agreement of interpretation of the dynamic course of duct changes in follow-up MRI/MRCP is of clinical importance but remains unknown. Our aims are therefore to assess the inter-reader agreement of interpretation of the course of duct changes in PSC and investigate if elimination of 3?D MRCP affects inter-reader agreement.

Materials and Methods: We studied 40 consecutive PSC-patients who underwent two liver MRI/MRCPs at two time points. Two readers independently evaluated the course of duct changes between the two time points in two imaging sets, one with and one without 3?D MRCP. The intraclass correlation coefficient (ICC) was calculated for evaluation of inter-reader and intra-reader agreement between the two time points and two imaging sets accordingly.

Results: Inter-reader agreement of the interpretation of the course of duct changes between the two time points was poor (ICC up to 0.224). Elimination of 3?D MRCP neither improved inter-reader agreement which was again poor (ICC up to 0.26) nor did it change considerably the way readers interpret the course of ducts changes (ICC for intra-reader agreement between 0.809 and 0.978).

Conclusions: Inter-reader agreement of the interpretation of radiological course of duct changes is poor in serial follow-up MRI/MRCP of PSC-patients. Elimination of 3?D MRCP does not increase inter-reader agreement but maintains an excellent intra-reader agreement for the interpretation of the dynamic course of bile duct changes.
  • Key points
  • Inter-reader agreement of interpretation of radiological course of bile duct changes between serial follow-up MRI/MRCP examinations of patients with PSC is poor.

  • Absence of 3D MRCP does not affect considerably the way readers interpret the radiological course of bile ducts changes.

  • When MRCP is absent or of low quality, utilization of other sequences seems to be helpful as an alternative for bile duct evaluation.

  相似文献   
48.
AIMS: To investigate if improved treatment of coronary heart disease and hypertension, the major causes of chronic heart failure (CHF), in the last 20 years has had an impact on the incidence of CHF and survival. METHODS: National Swedish registers on hospital discharges and cause-specific deaths were used to calculate age- and sex-specific trends and sex ratios for heart failure admissions and deaths. The study included all men and women 45 to 84 years old hospitalized for the first time for heart failure in 19 Swedish counties between 1988 and 2000, a mean annual population 2.9 million. A total of 156?919 hospital discharges were included. RESULT: In 1988, a total of 267 men and 205 women per 100?000 inhabitants (age adjusted) were discharged for the first time with a principal diagnosis of heart failure. After 1993 a yearly decrease was observed, with 237 men and 171 women per 100?000 inhabitants discharged during 2000. The 30-day mortality decreased significantly. The decrease in 1-year mortality was more pronounced in the younger age groups, with a total reduction in mortality of 69% among men and 80% among women aged 45-54 years. The annual decrease was 9% among men and 10% among women aged 45-54 years (95% CI -7% to -12% and -6% to -14% respectively) and 4% among men and 5% among women (95% CI -4% to -5% for both) aged 75-84 years. CONCLUSION: The decrease in incidence and improved prognosis after a first hospitalization for heart failure coincides with the establishment of ACE-inhibitor therapy, the introduction of beta-blockers for treatment of heart failure, home-care programmes for heart failure, and more effective treatment and prevention of underlying diseases. Notwithstanding, despite considerable improvement, 1-year mortality after a first hospitalization for heart failure is still high.  相似文献   
49.
When the lateralized readiness potential (LRP) is recorded in stimulus–response compatibility (SRC) tasks, two processes may overlap in the LRP, stimulus‐driven response priming and activation based on response selection rules. These overlapping processes are hard to disentangle with standard analytical tools. Here, we show that Residue Iteration Decomposition (RIDE), based on latency variability, separates the overlapping LRP components from a Simon task into stimulus‐driven and response‐related components. SRC affected LRP amplitudes only in the stimulus‐driven component, whereas LRP onsets were affected only in the response‐locked component. Importantly, the compatibility effect in reaction times was more similar to the effect in the onsets of the RIDE‐derived response‐locked LRP component than in the unseparated LRP. Thus, RIDE‐separated LRP components are devoid of distortions inherent to standard LRPs.  相似文献   
50.

Background

Episodic memory deficits affect the majority of patients with bipolar disorder (BD).

Aims

The study investigates episodic memory performance through different approaches, including behavioural measures, physiological parameters, and the underlying functional activation patterns with functional neuroimaging (fMRI).

Methods

26 Remitted BD patients and a matched group of healthy controls underwent a verbal episodic memory test together with monitored autonomic response, psychopathological ratings and functional magnetic resonance imaging (fMRI) during the verbal episodic memory test.

Results

Compared to healthy controls, BD patients performed significantly worse during the episodic memory task. The results further indicate that verbal episodic memory deficits in BD are associated with abnormal functional activity patterns in frontal, occipital and limbic regions, and an increase in stress parameters.

Limitations

We aimed to minimise sample heterogeneity by setting clear criteria for remission, based on the scores of a depression (BDI II) and mania scale (BRMAS) and on the DSM IV criteria. However, our patients were not symptom-free and scored higher on BDI II scores than the control group.

Conclusions

The results are of interest for the treatment of cognitive symptoms in BD patients, as persistent cognitive impairment may hamper full rehabilitation.  相似文献   
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