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81.
Articular cartilage composition and structure are maintained and remodeled by chondrocytes under the influence of loading. Exercise‐induced changes in the composition, structure, mechanical properties and tissue integrity of growing and aging hamster articular cartilage were investigated. Articular cartilage samples (n = 191) were harvested from the proximal tibiae of hamsters aged 1, 3, 6, 12 and 15 months. The hamsters were divided into runners and controls. The runners had free access to a running wheel between 1 and 3 months (runner groups 3‐, 12‐ and 15‐month‐old hamsters) or 1 and 6 months (runner group 6‐month‐old hamsters) of age. Control animals were subjected to a sedentary lifestyle. Mechanical indentation tests and depth‐wise compositional and structural analyses were performed for the cartilage samples. Furthermore, the integrity of articular cartilage was assessed using histological osteoarthritis grading. Exercise affected the collagen network organization after a 5‐month exercise period, especially in the middle and deep zones. However, no effect on the mechanical properties was detected after exercise. Before the age of 12 months, the runners showed less osteoarthritis than the controls, whereas at 15 months of age the situation was reversed. It is concluded that, in hamsters, physical exercise at a young age enhances cartilage maturation and alters the depth‐wise cartilage structure and composition. This may be considered beneficial. However, exercise at a young age demonstrated adverse effects on cartilage at a later age with a significant increase in the incidence of osteoarthritis.  相似文献   
82.
The Centers for Disease Control and Prevention's (CDC) expanded testing initiative (ETI) aims to bolster HIV testing among populations disproportionately affected by the HIV epidemic by providing additional funding to health departments serving these communities. ETI prioritizes testing in clinical settings; therefore, we examined the relationship between state-level ETI participation and past-year HIV testing among a racially/ethnically diverse sample of adult respondents to the 2012 Behavioral Risk Factor Surveillance System who accessed health services within the 12 months prior to being interviewed. Controlling for individual- and state-level characteristics in a multilevel logistic regression model, ETI participation was independently and positively associated with past-year testing, but this association varied by race/ethnicity. Hispanics had higher odds (adjusted odds ratio [AOR]: 1.49; 95% CI: 1.11–2.02) and American Indian/Alaska Natives had lower odds (AOR: 0.66; 95% CI: 0.43–0.99) of testing if they resided in states with (vs. without) ETI participation. State-level ETI participation did not significantly alter past-year testing among other racial/ethnic groups. Prioritizing public health resources in states most affected by HIV can improve testing patterns, but other mechanisms likely influence which racial/ethnic groups undergo testing.  相似文献   
83.
The purpose of this research was to study how consumers respond to differences in the freshness of lettuce based only on sensory properties in the foodservice context. Another objective was to measure consumer response to the modification of the consumption context. Data was collected from consumer studies in two separate restaurants with three different products (n = 238). The reference sample was a packaged ready-to-eat lettuce, which was compared using two freshly prepared samples. The results indicated that consumers did recognize differences between product properties that depend on the level of freshness when served in a foodservice environment. By serving fresh products, the perceived level of sensory quality showed a significant increase.  相似文献   
84.
Hair cell death is a major cause of hearing impairment. Preservation of surface barrier upon hair cell loss is critical to prevent leakage of potassium-rich endolymph into the organ of Corti and to prevent expansion of cellular damage. Understanding of wound healing in this cytoarchitecturally complex organ requires ultrastructural 3D visualization. Powered by the serial block-face scanning electron microscopy, we penetrate into the cell biological mechanisms in the acute response of outer hair cells and glial-like Deiters’ cells to ototoxic trauma in vivo. We show that Deiters’ cells function as phagocytes. Upon trauma, their phalangeal processes swell and the resulting close cellular contacts allow engulfment of apoptotic cell debris. Apical domains of dying hair cells are eliminated from the inner ear sensory epithelia, an event thought to depend on supporting cells’ actomyosin contractile activity. We show that in the case of apoptotic outer hair cells of the organ of Corti, elimination of their apices is preceded by strong cell body shrinkage, emphasizing the role of the dying cell itself in the cleavage. Our data reveal that the resealing of epithelial surface by junctional extensions of Deiters’ cells is dynamically reinforced by newly polymerized F-actin belts. By analyzing Cdc42-inactivated Deiters’ cells with defects in actin dynamics and surface closure, we show that compromised barrier integrity shifts hair cell death from apoptosis to necrosis and leads to expanded hair cell and nerve fiber damage. Our results have implications concerning therapeutic protective and regenerative interventions, because both interventions should maintain barrier integrity.  相似文献   
85.
Cancer Causes & Control - We explored renal cell cancer (RCC) survival among users of antihypertensive medication as hypertension is proposed to be a risk factor for RCC and ACE-inhibitors and...  相似文献   
86.
Inverse imaging (InI) supercharges the sampling rate of traditional functional MRI 10-100 fold at a cost of a moderate reduction in spatial resolution. The technique is inspired by similarities between multi-sensor magnetoencephalography (MEG) and highly parallel radio-frequency (RF) MRI detector arrays. Using presently available 32-channel head coils at 3T, InI can be sampled at 10 Hz and provides about 5-mm cortical spatial resolution with whole-brain coverage. Here we discuss the present applications of InI, as well as potential future challenges and opportunities in further improving its spatiotemporal resolution and sensitivity. InI may become a helpful tool for clinicians and neuroscientists for revealing the complex dynamics of brain functions during task-related and resting states.  相似文献   
87.
IntroductionIn middle-aged men, the associations between long-term depressive symptoms and circulating testosterone levels are poorly known, although it is known that testosterone levels decrease with age.MethodsA health questionnaire was mailed to a population-based sample from the National Population Register in 1998, 1999, and 2001. Based on their self-reported mental symptoms, a total of 116 men were selected for clinical examination in 2005. Half of them had high and the others low levels of adverse mental symptoms in all three previous follow-ups. A structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders-IV was performed. Depressive symptoms were assessed with the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). The Aging Males’ Symptoms scale was also compiled and testosterone levels were determined.ResultsIn the entire study sample, serum free testosterone levels correlated negatively with both BDI and HDRS scores. In the hypogonadism group (based on free testosterone, 19.8% of the sample), clinically significant depression (BDI score ≥ 13) was more than three times as frequent as in the other men (34.8% vs. 10.4%), the odds ratio after multiple adjustments being 4.98 (95% confidence interval 1.66–14.95). A decrease in sexual desire was common in hypogonadism (36%). Nevertheless, it also associated with clinically significant depression, irrespective of free testosterone levels.DiscussionLong-term and current depressive symptoms, a decreased sexual desire, and low serum free testosterone levels are associated in middle-aged men. Hypogonadism per se and as a cause of decreased sexual desire may be a contributory and possibly treatable factor underlying male depression.ConclusionsThe findings highlight the need for hormonal status assessment in middle-aged depressive men. Hintikka J, Niskanen L, Koivumaa-Honkanen H, Tolmunen T, Honkalampi K, Lehto SM, and Viinamäki H. Hypogonadism, decreased sexual desire, and long-term depression in middle-aged men. J Sex Med 2009;6:2049–2057.  相似文献   
88.
The field of thoracic surgery is a rapidly developing field due to exciting developments in technology and oncologic treatments as well as continuous innovation in surgical technique. Although the population of Finland is relatively small, general thoracic surgery is represented at a high level in five centralized university centers, Helsinki University Hospital, Tampere University Hospital, Turku University Hospital, Kuopio University Hospital and Oulu University Hospital. Thus, high case volume and good results are achieved in these centers. Here, we describe a short history, current state and future prospects of the field of cardiothoracic surgery in Finland, with a focus on general thoracic surgery and the perspective of Helsinki University Hospital. From the field’s birth in Finland, marked by the first lobectomy, in the late 1930’s, it has grown and adapted more and more modern techniques such as totally minimally invasive esophagectomy and robotic lung cancer surgery. Nowadays, most of general thoracic surgery in Helsinki University Hospital is either minimally invasive or robotic and open surgery is the exception to the norm. Helsinki University Hospital has a strong presence in the European general thoracic surgery community and aims to do so in the future by investing on training & education, research and surgical innovation.  相似文献   
89.
Primary central nervous system lymphoma (PCNSL) is an aggressive brain disease where lymphocytes invade along perivascular spaces of arteries and veins. The invasion markedly changes (peri)vascular structures but its effect on physiological brain pulsations has not been previously studied. Using physiological magnetic resonance encephalography (MREGBOLD) scanning, this study aims to quantify the extent to which (peri)vascular PCNSL involvement alters the stability of physiological brain pulsations mediated by cerebral vasculature. Clinical implications and relevance were explored. In this study, 21 PCNSL patients (median 67y; 38% females) and 30 healthy age‐matched controls (median 63y; 73% females) were scanned for MREGBOLD signal during 2018–2021. Motion effects were removed. Voxel‐by‐voxel Coefficient of Variation (CV) maps of MREGBOLD signal was calculated to examine the stability of physiological brain pulsations. Group‐level differences in CV were examined using nonparametric covariate‐adjusted tests. Subject‐level CV alterations were examined against control population Z‐score maps wherein clusters of increased CV values were detected. Spatial distributions of clusters and findings from routine clinical neuroimaging were compared [contrast‐enhanced, diffusion‐weighted, fluid‐attenuated inversion recovery (FLAIR) data]. Whole‐brain mean CV was linked to short‐term mortality with 100% sensitivity and 100% specificity, as all deceased patients revealed higher values (n = 5, median 0.055) than surviving patients (n = 16, median 0.028) (p < .0001). After adjusting for medication, head motion, and age, patients revealed higher CV values (group median 0.035) than healthy controls (group median 0.024) around arterial territories (p ≤ .001). Abnormal clusters (median 1.10 × 105mm3) extended spatially beyond FLAIR lesions (median 0.62 × 105mm3) with differences in volumes (p = .0055).  相似文献   
90.
Purpose: This article explores which concrete factors hinder or facilitate the cooperation of return-to-work (RTW) professionals in a complex system of multiple stakeholders.

Method: The empirical material consists of in-depth interviews with 24 RTW professionals from various organizations involved in work disability management in Finland. The interviews were analyzed using thematic content analysis.

Results: The study revealed several kinds of challenges in the cooperation of the professionals. These were related to two partly interrelated themes: communication and distribution of responsibility. The most difficult problems were connected to the cooperation between public employment offices and other stakeholders. However, the study distinguished notable regional differences depending primarily on the scale of the local network. The main areas of improvement proposed by the interviewees were related to better networking of case managers and expansion of expertise.

Conclusions: The article argues for the importance of systematic networking and stresses the role of public employment services in the multi-actor management of work disabilities. The article contributes to existing work disability case management models by suggesting the employment administration system as an important component in addition to health care, workplace and insurance systems. The study also highlights the need for expansion of expertise in the field.

  • Implications for Rehabilitation
  • Cooperation between RTW professionals in public employment offices and other organizations involved in work disability management was considered inadequate.

  • In order to improve the cooperation of RTW professionals, the stakeholders need to create more systematic ways of communication and networking with professionals in other organizations.

  • There is a need to expand the expertise in work disability management and rehabilitation, partly by increasing the role of other professionals than physicians.

  相似文献   
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