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51.
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ObjectivesAcute hospitalization may lead to a decrease in muscle measures, but limited studies are reporting on the changes after discharge. The aim of this study was to determine longitudinal changes in muscle mass, muscle strength, and physical performance in acutely hospitalized older adults from admission up to 3 months post-discharge.DesignA prospective observational cohort study was conducted.Setting and ParticipantsThis study included 401 participants aged ≥70 years who were acutely hospitalized in 6 hospitals. All variables were assessed at hospital admission, discharge, and 1 and 3 months post-discharge.MethodsMuscle mass in kilograms was assessed by multifrequency Bio-electrical Impedance Analysis (MF-BIA) (Bodystat; Quadscan 4000) and muscle strength by handgrip strength (JAMAR). Chair stand and gait speed test were assessed as part of the Short Physical Performance Battery (SPPB). Norm values were based on the consensus statement of the European Working Group on Sarcopenia in Older People.ResultsA total of 343 acute hospitalized older adults were included in the analyses with a mean (SD) age of 79.3 (6.6) years, 49.3% were women. From admission up to 3 months post-discharge, muscle mass (?0.1 kg/m2; P = .03) decreased significantly and muscle strength (?0.5 kg; P = .08) decreased nonsignificantly. The chair stand (+0.7 points; P < .001) and gait speed test (+0.9 points; P < .001) improved significantly up to 3 months post-discharge. At 3 months post-discharge, 80%, 18%, and 43% of the older adults scored below the cutoff points for muscle mass, muscle strength, and physical performance, respectively.Conclusions and ImplicationsPhysical performance improved during and after acute hospitalization, although muscle mass decreased, and muscle strength did not change. At 3 months post-discharge, muscle mass, muscle strength, and physical performance did not reach normative levels on a population level. Further research is needed to examine the role of exercise interventions for improving muscle measures and physical performance after hospitalization.  相似文献   
53.

Rationale

Lithium has been a standard pharmacological treatment for bipolar disorder over the last 60 years; however, the molecular targets through which lithium exerts its therapeutic effects are still not defined. Attenuation of the phosphatidylinositol signal transduction pathway as a consequence of inhibition of inositol monophosphatase (IMPase) has been proposed as one of the possible mechanisms for lithium-induced mood stabilization.

Objectives

The objective was to study the behavioral effect of the specific competitive IMPase inhibitor L-690,330 in mice in the lithium-sensitive pilocarpine-induced seizures paradigm and the forced swim test (FST).

Methods

The inhibitor was administered intracerebroventricularly in liposomes.

Results

L-690,330 increased the sensitivity to subconvulsive doses of pilocarpine and decreased immobility time in the FST.

Conclusions

It is possible that the behavioral effects of lithium in the pilocarpine-induced seizures and in the FST are mediated through the inhibition of IMPase, but reversal of the inhibitor’s effect with intracerebroventricular inositol would be an important further step in proof.  相似文献   
54.

Background  

Food frequency questionnaires (FFQs) have been validated in pregnant women, but few studies have focused specifically on low-income women and minorities. The purpose of this study was to examine the validity of the Harvard Service FFQ (HSFFQ) among low-income American Indian and Caucasian pregnant women.  相似文献   
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Limb lengthening by distraction osteogenesis has a high complication rate. Much of the response of muscle and nerve to distraction is still unknown. Thirteen children, mean age 12.6 yr (8.4-17.3) were surgically treated by the Ilizarov procedure for acquired and congenital femoral limb-length discrepancy. All children showed a decrease in muscle strength in the quadriceps, shortly after the operation, followed by an improvement before distraction started. After an elongation in the early phase of distraction (1 to 2 cm), muscle weakness was again observed and the muscle strength gradually increased after ending of distraction. To provide an explanation for this clinical observation, in one patient (limb lengthening of 4.1 cm) muscle strength measurements were extended with investigations of Hoffman (H) reflex of m. vastus medialis and determination of muscle-fiber conduction velocity of m. vastus lateralis by using the invasive method (IMFCV). The examinations were performed every two weeks during 20 weeks and 12 weeks after removing the cast. A severe decrease in muscle strength of the corrected limb was found after 1.2 cm of distraction with a recovery in muscle strength before lengthening was ended. EMG study showed the same tendency. Denervation was observed as evidence by positive sharp waves and reduced IMFCV findings. Evidence for reinnervation before lengthening was ended, was found by an increased range of velocities consisting of a combination of slow potentials and gradual increase of the velocity of reinnervated fibers (increased Fast/Slow ratio). The latencies of M waves and H-M interval from both legs separated as well after 2.25 cm of distraction. At the end of the follow-up period, the H-M interval reached the preoperative value. It is suggested that these neurogenic changes are an effect of axonal dysfunction and the local effect due to intraoperative trauma and stretching might affect nerve blood flow adversely.  相似文献   
58.
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.  相似文献   
59.
Wenger  RH; Wicki  AN; Walz  A; Kieffer  N; Clemetson  KJ 《Blood》1989,73(6):1498-1503
We report here the cloning of the cDNA coding for platelet connective tissue-activating peptide-III (CTAP-III) from a lambda gt11 expression library prepared using messenger RNA (mRNA) isolated from human platelets. The open reading frame of the clone coded for a protein with 128 amino acid residues. Since the precursor of CTAP-III, platelet basic protein (PBP is 94 amino acids long, the 5'-translated region of the cDNA codes for a leader sequence 34 amino acids long. This leader sequence, like the sequence of mature CTAP-III, shows significant homology to the sequence of platelet factor 4 (PF4), the only other platelet specific alpha-granule protein cloned until now, from a human erythroleukemic (HEL) cell line-derived cDNA library. These leader sequences are probably critical for targeting such proteins to the alpha-granule. Northern blot hybridization with platelet and megakaryocyte mRNA shows a single species mRNA of approximately 0.8 kb, suggesting that the corresponding cDNA is full length. The cloning of platelet specific CTAP-III provides additional evidence for the platelet specificity of the cDNA library used.  相似文献   
60.
A telephone survey was used to assess knowledge of the transmission, prevalence, and infectivity of acquired immunodeficiency syndrome (AIDS), and the safety of casual contact among 214 randomly selected university students. Males were more knowledgeable than females overall (odds ratio [OR], men/women = 4.8). Although most students understood the dangers of unprotected sex and intravenous needle sharing, up to 30% believed some kinds of casual contact (e.g., shared eating utensils) can transmit AIDS. Older students (greater than or equal to 23 yrs) were more knowledgeable than those 17 to 19 years old about the safety of casual contact (OR = 3.8). Students are in need of education programs that stress the ways AIDS is not transmitted. Since most students identified newspapers and television as their main sources of information, these may be effective vehicles for education efforts.  相似文献   
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