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1.
Continuous erythropoietin receptor activator (CERA) is a third-generation erythropoiesis-stimulating agent that was developed for the treatment of anemia. However, misuse of CERA for doping in endurance sports has been reported. Previous studies have shown blood as the matrix of choice for the detection of CERA, due to its high molecular weight. The use of dried blood spots (DBSs) for anti-doping purposes constitutes a complementary approach to the standard urine and venous blood matrices and could facilitate sample collection and increase the number of blood samples available for analysis due to reduced costs of sample collection and transport. Here, we investigated whether CERA could be indirectly detected in extracts of single DBSs using an erythropoietin-specific immunoassay that is capable of providing results within approximately 2 h. Reconstituted DBS samples were prepared from mixtures of red blood cell pellets and serum samples. The samples were collected in a previous clinical study in which six healthy volunteers were injected with a single, 200 μg dose of CERA. Using a commercially available ELISA kit, CERA was detected in the DBSs with a detection window of up to 20 days post-injection. Furthermore, in order to demonstrate the fitness-for-purpose, three authentic doping control serum samples, which were identified as containing CERA, were analyzed by the presented methodological approach on DBS. The testing procedure described here could be used as a fast and cost-effective method for the detection of CERA abuse in sport.  相似文献   
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We report the case of a 22-year-old woman who is suspected of having primary Sj?gren s syndrome. She complaining of bilateral swelling of eyelids and the parotid glands of three weeks duration. Physical examination revealed a bilateral enlargement of both parotid glands, which were solid and painful. Sj?gren s syndrome was suspected at that stage, and the serologic and specific analysis were done. All these tests didn t find any autoimmune or visceral features typical of Sj?gren s syndrome and autoantibodies were negative. During follow-up time the right facial nerve palsy developed. Pulmonary radiography revealed bihilar lymphadenopathy and labial salivary gland biopsy revealed non-caseating granuloma. The patient was classified as having stage I sarcoidosis. This case demonstrates the importance of being aware of the leading clinical signs and symptoms in case of Heerfordt syndrome.  相似文献   
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BACKGROUND:

The present review examines the role of intra-cellular compartmentation of energy metabolism in vivo.

OBJECTIVE:

To compare the kinetics of the activation of mitochondrial respiration in skinned cardiac fibres by exogenous and endogenous adenine nucleotides in dependence of the modulation of cellular structure and contraction.

METHODS:

Saponin-permeabilized cardiac fibres or cells were analyzed using oxygraphy and confocal microscopy.

RESULTS:

Mitochondria respiration in fibres or cells was upregulated by cumulative additions of ADP to the medium with an apparent Km of 200 μM to 300 μM. When respiration was stimulated by endogenous ADP produced by intracellular ATPases, a near maximum respiration rate was achieved at an ADP concentration of less than 20 μM in the medium. A powerful ADP-consuming system, consisting of pyruvate kinase and phosphoenolpyruvate, that totally suppressed the activation of respiration by exogenous ADP, failed to abolish the stimulation of respiration by endogenous ADP, but did inhibit respiration after the cells were treated with trypsin. The addition of up to 4 μM of free Ca2+ to the actively respiring fibres resulted in reversible hypercontraction associated with a decreased apparent Km for exogenous ADP. These changes were fully abolished in fibres after the removal of myosin by KCl treatment.

CONCLUSIONS:

Mitochondria and ATPases, together with cytoskeletal proteins that establish the structural links between mitochondria and sarcomeres, form complexes – intracellular energetic units (ICEUs) – in cardiac cells. Within the ICEUs, the mitochondria and ATPases interact via specialized energy transfer systems, such as the creatine kinase- and adenylate kinase-phosphotransfer networks, and direct ATP channelling. Disintegration of the structure and function of ICEUs results in dyscompartmentation of adenine nucleotides and may represent a basis for cardiac diseases.  相似文献   
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PURPOSE: To report the long-term outcome of patients with lifestyle-limiting claudication after percutaneous transluminal angioplasty (PTA) of the femoropopliteal arteries. MATERIALS AND METHODS: Between 1989 and 1992, 173 consecutive claudicant patients (mean age, 65 years; age range, 41-90 years) underwent PTA in 218 limbs; all interventions included femoral and/or popliteal arterial segments, and additional iliac (n = 27) and infrapopliteal (n = 11) arterial lesions were also treated. Patients were followed up for 7-10 years. Altogether, 37 (17%) limbs were classified as Fontaine class 2A, and 181 (83%) were class 2B. Average length of the primary lesion was 5.2 cm. Reinterventions were analyzed. Patency rates and patient survival were assessed by means of life table analysis. Cox-Mantel tests and Cox proportional hazards models were used to define associated independent determinants. Development of chronic critical ischemia (CCI) and its determinants was assessed by using the Pearson chi(2) test and multiple logistic regression analysis. RESULTS: The primary and secondary patencies (+/- standard error of the estimate), respectively, were 46% +/- 3 and 63% +/- 3 at 1 year, 25% +/- 3 and 41% +/- 4 at 5 years, and 14% +/- 3 and 22% +/- 4 at 10 years. One-third (71 of 218) of the limbs required repeat interventions, including surgical revascularization in 35 limbs. Fourteen (6.4%) limbs developed CCI, resulting in a 0.8% incidence per year. In multivariate analysis, poor postinterventional peripheral runoff was an indicator of increased risk of CCI development (P =.03). CONCLUSION: Although the long-term patency rates of PTA of the femoropopliteal arteries in claudicant patients were poor, the acceptable number of reinterventions and the low frequency of development of CCI imply the long-term benefits achievable with this treatment.  相似文献   
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BACKGROUND: Moderate alcohol drinking is suggested to be beneficial for cognitive functions, but the results of previous studies have varied greatly. Little is known about the effects of midlife alcohol drinking on the cognitive functions later in life. METHODS: Participants were derived from random, population-based samples studied in Eastern Finland in 1972, 1977, 1982, or 1987. A total of 1,341 participants were reexamined in 1998, after an average follow-up period of 21 years, at ages 65-79 years. RESULTS: The participants who did not drink alcohol at midlife had a poorer performance in episodic memory, psychomotor speed, and executive function in late life as compared with infrequent and frequent drinkers, adjusted for sociodemographic and vascular factors. Also late-life nondrinkers had poorer psychomotor speed and executive function. These findings were evident especially among nonsmokers. Further, no interactions between apolipoprotein E4 and alcohol or sex and alcohol were found. CONCLUSIONS: Alcohol drinking both at midlife and later is favorably related to the function in several cognitive domains, including episodic memory, psychomotor speed, and executive function, in late life. However, it is not clear whether the association is causal, what is the possible mechanism, and what would be a safe limit of drinking for the best cognitive function.  相似文献   
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Purpose

The aim of this study was to examine the association of serum glucose, insulin, and insulin resistance with cognitive functioning 7 years later in a longitudinal population-based study of Finnish older adults.

Methods

Serum glucose and insulin were measured at baseline in 269 dementia-free individuals aged 65-79 years, from the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study. Insulin resistance was estimated with the homeostasis model assessment (HOMA-IR). Participants were reexamined 7 years later, and global cognition, episodic memory, executive functioning, verbal expression, and psychomotor speed were assessed, both at baseline and at follow-up. Multiple linear regression was used to investigate the associations with cognitive performance at follow-up, after adjusting for several potential confounders, including common vascular risk factors.

Results

In the multivariable-adjusted linear regression models, no associations of insulin resistance with cognitive functioning were observed. After excluding 19 incident dementia cases, higher baseline HOMA-IR values were related to worse performance in global cognition (β [standard error (SE)] -.050 [0.02]; P?=?.043) and psychomotor speed (β [SE] -.064 [.03]; P?=?[.043]) 7 years later. Raised serum insulin levels were associated with lower scores on global cognition (β [SE] -.054 [.03]; P?=?.045) and tended to relate to poorer performance in psychomotor speed (β [SE] -.061 [.03]; P?=?.070).

Conclusions

Serum insulin and insulin resistance may be independent predictors of cognitive performance 7 years later in elderly individuals without dementia. Randomized controlled trials are needed to determine this issue.  相似文献   
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