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1.
Ascofuranone, a prenylphenol antibiotic isolated from a phytopathogenic fungus, Ascochyta visiae, strongly inhibited both glucose-dependent cellular respiration and glycerol-3-phosphate-dependent mitochondrial O2 consumption of long slender bloodstream forms of Trypanosoma brucei brucei. This inhibition was suggested to be due to inhibition of the mitochondriai electron-transport system, composed of glycerol-3-phosphate dehydrogenase (EC 1.1.99.5) and plant-like alternative oxidase. Ascofuranone noncompetitively inhibited the reduced coenzyme Q1-dependent O2 uptake of the mitochondria with respect to ubiquinol (Ki = 2.38 nM). Therefore, the susceptible site is deduced to be the ubiquinone redox machinery which links the two enzyme activities. Further, ascofuranone in combination with glycerol completely blocked energy production, and potently inhibited the in vitro growth of the parasite. Our findings suggest that ascofuranone might be a promising candidate for the chemotherapeutic agents of African trypanosomiasis.  相似文献   

2.
BACKGROUND AND PURPOSE: The purpose of this study was to assess the intrasession and intersession reliability of measurements of quantitative gait variables at two self-selected walking speeds. SUBJECTS: Forty-one patients with osteoarthritis in one or both knees who were referred for physical therapy participated. METHODS: Three measurements were made at 1-week intervals. The quantitative gait variables of walking speed, cadence, and stride length were measured using an 8-m electronic footswitch walkway. At each measurement, subjects were asked to walk five times at a self-selected pace that they considered to be normal and five times at a self-selected pace that they considered to be fast. RESULTS: At the normal walking speed, although intraclass correlations were consistently high for all gait variables, an additive factor within and across the first two measurements was evident even when a mean of several trials was used. At the fast walking speed, the intraclass correlations were again consistently high for all gait variables, but there were no changes within or across the measurements. CONCLUSION AND DISCUSSION: The data suggest that quantitative gait analysis is a practical objective assessment tool for persons with osteoarthritis of the knee. Gait at the fast walking speed, however, will provide the more reliable stable measure on which to evaluate the effect of therapy when compared with gait at the normal walking speed. The comparative responsiveness to change between the two walking speeds still needs to be determined.  相似文献   

3.
The reliability and validity of a situational interview (e.g., Latham, Saari, Pursell, & Campion, 1980) were examined for a sales position. In a pilot study, the interrater reliability of the interview was higher than that typically observed for interviews (r?=?.84). However, the estimate was probably inflated because the reliability was computed on the same data used in the item analysis phase of interview development. In a predictive validation study, the situational interview was shown to be valid (r?=?.45) in the prediction of sales productivity. After correcting for attenuation in the criterion, a validity coefficient of .47 was observed. Future research directions with respect to the situational interview are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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In susceptible mouse strains, the wild-type Daniel's (wt-DA) strain of Theiler's murine encephalomyelitis virus induces a persistent central nervous system (CNS) infection with chronic demyelination. The virus is cleared from resistant mice with no resulting demyelination. We characterized the role of the DA L* protein in late demyelination and persistent infection. The DA genome has two alternative reading frames, encoding the virus polyprotein and L*, respectively. The mutant virus DAL*-1 fails to synthesize L* and does not persist in the CNS of wt-DA-susceptible SJL/J or B10.S mice. Since class I-restricted cytotoxicity has been shown to determine resistance to virus persistence and demyelination in this model, virus-specific cytotoxicity in the CNS of DA-resistant (B6 or B10) and -susceptible (SJL/J and B10.S) mice during the acute stage of DA and DAL*-1 infection was characterized. Following intracerebral inoculation with DAL*-1, virus-specific Db- and Kb-restricted CTLs were demonstrated in the CNS of resistant B10 mice, whereas only Db-restricted CTL were found in wt-DA-inoculated mice. CTLs specific to wt-DA or DAL*-1 recognized class I-presented peptides from either of the viruses. Of particular interest, Ks-restricted virus-specific cytotoxicity-restricted CTLs were identified in the CNS of susceptible SJL/J (H-2s) and B10.S (H-2s) mice inoculated with DAL*-1. In contrast, no virus-specific CTLs were identified in the CNS of SJL/J and B10.S mice inoculated with wt-DA. We propose that L* inhibits the generation of H-2K-restricted virus-specific cytotoxicity in the CNS, permitting a persistent infection in susceptible strains, with subsequent inflammatory demyelination in the CNS similar to that in human multiple sclerosis.  相似文献   

6.
Illumination of bovine pancreatic ribonuclease A (RNase A) in solution in the presence of rose bengal as a photosensitizer resulted in the progressive formation of enzyme dimers, trimers, tetramers and higher oligomers, as measured by gel electrophoresis and size exclusion chromatography. Oxygen was necessary for crosslink formation, and azide inhibition studies indicated that singlet oxygen was involved in the process. Chemical modification of His residues (with diethyl pyrocarbonate) and/or Lys residues (with acetic acid N-hydroxysuccinimide ester) in the enzyme decreased crosslinking, suggesting the participation of these two amino acid residues in the reaction. Met and cystine residues did not appear to be involved. Similar studies have shown that model N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers containing epsilon-aminocaproic acid side chains terminating in His or Lys residues are photodynamically crosslinked via His-His or His-Lys interactions. Treatment of crosslinked RNase A and its His, Lys and Lys-His derivatives for 5 min at 97 degrees C in a dithiothreitol-sodium dodecyl sulfate mixture efficiently ruptured a major part of the photodynamically formed crosslinks; treatment with the detergent alone had no effect. Similar results were obtained with the crosslinked amino acid-containing HPMA copolymers, suggesting that photodynamic crosslinks involving His-His and His-Lys interaction are chemically the same in RNase A and the copolymer model.  相似文献   

7.
In 2 studies, test–retest data (interval approximately 6 mo) were collected comprising measures of preadolescent self-concepts in 7 areas, teachers' ratings of student self-concepts in these same areas, and academic ability. Five 4th-grade, 16 5th-grade, and 14 6th-grade classes were studied. Student self-concept ratings were internally consistent, reasonably stable over time, and measured distinct components of self-concept consistent with the design of the instrument used to collect the ratings. Student self-concepts in each area were significantly correlated with teacher ratings of their self-concepts in the same area, and student–teacher agreement was specific to particular dimensions. Academic ability measures were uncorrelated with self-concept in 4 nonacademic areas and most highly correlated with the particular area of academic self-concept most logically related to the particular ability measure. Thus, multiple dimensions of self-concept showed a logical and consistent pattern of relationships with a variety of criteria. Changes in self-concept over the 6-mo period were also reasonably reliable, multidimensional, and specific to each area of self-concept, but they were not correlated with changes in the criterion variables. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The development of arthrotic-like changes following the resection of the cruciate ligaments in the knee joint of rabbits has been studied at intervals from 2 weeks to 10 months in 35 animals. Signs of cartilage degeneration were followed by changes in the subchondral bone, where formation of osteophytes and condensation took place. An increased vascular supply was demonstrated by microangiographic and scintigraphic investigations. The uptake of 18F and 99mTc-polyphosphate reached a maximal value about 2 months after the operation and then diminished despite further development of arthrotic changes.  相似文献   

10.
OBJECTIVE: Neuromuscular joint protection requires proprioceptive input and motor output. Impairment of proprioception in knee osteoarthritis (OA) may contribute to, and/or result from, the disease. If this impairment was exclusively a local result of OA, a between-knee difference would be expected in patients with unilateral OA (UOA). To explore causal directions, 2 hypotheses were tested: 1) proprioception is worse in UOA patients versus elderly controls; 2) proprioception is worse in the arthritic knee versus the unaffected knee in UOA patients. METHODS: Twenty-eight UOA patients (Kellgren-Lawrence grade > or =2 in 1 knee and <2 in the other knee) and 29 elderly controls were enrolled. The unaffected knee of each UOA patient and both knees of the elderly controls were required to meet symptom, examination, and radiographic criteria. Proprioception (detection threshold of joint displacement after slow, passive, automated knee motion), body mass index, pain, functional status, range of motion, and laxity were measured. RESULTS: UOA patients had worse proprioception than did elderly controls, in either knee. A between-knee difference was not found in UOA patients. CONCLUSION: Impaired proprioception is not exclusively a local result of disease in knee OA. The relative importance of impaired proprioception in the development and progression of knee OA will require longitudinal study.  相似文献   

11.
OBJECTIVE: Obesity is often associated with knee osteoarthritis (OA) and with chronic hyperinsulinemia. The aim of our study was to investigate the relationship between overweight patients and OA of the knee. METHODS: Forty-eight overweight outpatients (40 women and 8 men) were recruited into the study. They were separated into 2 groups: Group 1 patients with OA of the knee and Group 2 subjects without OA of the knee. Serum insulin levels were determined in all patients. RESULTS: Insulin levels were statistically higher in patients with OA (p < 0.01) compared to subjects without OA. CONCLUSION: Our data suggest that insulin may play a role in the pathogenesis of OA of the knee in overweight patients.  相似文献   

12.
We retrospectively studied 369 cases of knee osteoarthritis in 240 patients seen at the Cocody Teaching Hospital in Abidjan, Ivory Coast, from November 1984 through March 1989. There were 126 cases (34.14%) of patellofemoral osteoarthritis, 104 cases (28.18%) of femorotibial osteoarthritis and 139 cases (37.66%) of global knee osteoarthritis (defined as patellofemoral and femorotibial osteoarthritis in the same joint). There was a marked female bias (80.42% of patients). Onset was earlier in patellofemoral osteoarthritis (51.25 years) than in femorotibial osteoarthritis (57.85 years). Half the patients (51.25%) were housewives. The Akan and Mandé ethnic groups contributed 61.54% and 33.03% of patients, respectively. Obesity was present in 19.04% of cases of patellofemoral osteoarthritis and in 10.57% of cases of femorotibial osteoarthritis. Of the patients with femorotibial osteoarthritis, 20.20% had a history of arthritis of the knee and of those with global knee osteoarthritis, 12.23% reported a prior injury to the knee. Varus deformity was found in 24.03% and valgus deformity in 19.23% of the patients with femorotibial osteoarthritis.  相似文献   

13.
This study examined the attitudes toward breastfeeding of medical professionals working with pregnant or new mothers. Most advocated breastfeeding to mothers who had not made an infant feeding decision; fewer talked about breastfeeding during the first trimester; and many recommended that mothers supplement a breastfed infant with prepared commercial baby milk. All agreed that a mother's return to work led to early discontinuance of breastfeeding and that the family is a major influence on a mother's decision to breastfeed. To increase the prevalence of breastfeeding, the study group recommended prenatal education, participation in support groups, and promotion of breastfeeding through the media.  相似文献   

14.
OBJECTIVE: The safety and effectiveness of pulsed electrical stimulation was evaluated for the treatment of osteoarthritis (OA) of the knee. METHODS: A multicenter, double blind, randomized, placebo controlled trial that enrolled 78 patients with OA of the knee incorporated 3 primary efficacy variables of patients' pain, patients' function, and physician global evaluation of patients' condition, and 6 secondary variables that included duration of morning stiffness, range of motion, knee tenderness, joint swelling, joint circumference, and walking time. Measurements were recorded at baseline and during the 4 week treatment period. RESULTS: Patients treated with the active devices showed significantly greater improvement than the placebo group for all primary efficacy variables in comparisons of mean change from baseline to the end of treatment (p < 0.05). Improvement of > or = 50% from baseline was demonstrated in at least one primary efficacy variable in 50% of the active device group, in 2 variables in 32%, and in all 3 variables in 24%. In the placebo group improvement of > or = 50% occurred in 36% for one, 6% for 2, and 6% for 3 variables. Mean morning stiffness decreased 20 min in the active device group and increased 2 min in the placebo group (p < 0.05). No statistically significant differences were observed for tenderness, swelling, or walking time. CONCLUSION: The improvements in clinical measures for pain and function found in this study suggest that pulsed electrical stimulation is effective for treating OA of the knee. Studies for longterm effects are warranted.  相似文献   

15.
The development and psychometric properties of the Memory Self-Efficacy Questionnaire (MSEQ), a self-report measure of memory ability (Self-Efficacy Level) and confidence (Self-Efficacy Strength), are described. The MSEQ was rationally constructed using 50 memory items with face and content validity. The MSEQ and its alternate versions were examined in three experiments with younger and older adult samples. Satisfactory estimates of internal consistency and test–retest stability were obtained. Canonical correlation analyses provided preliminary support for the MSEQ's criterion and construct validity. Although additional psychometric work is needed, this initial investigation of the MSEQ suggests that it may be a useful tool for research on memory self-evaluation in adult age groups. Reliability and validity are strong, the questionnaire shows expected adult age differences in self-evaluation, and the theoretical framework of self-efficacy provides useful hypotheses regarding developmental changes and individual differences in self-evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
OBJECTIVE: Depressive personality disorder was introduced into DSM-IV's appendix amid controversy. While that disorder appears to be a reliable and valid one, the authors offer new data about its relationship to major depression, dysthymic disorder, and other personality disorders. METHOD: The authors assessed 54 subjects with early-onset, long-standing mild depressive features for depressive personality disorder, axis I and axis II disorders, family history, and treatment history; they conducted follow-up interviews 1 year after the baseline assessment. Subjects with (N=30) and without (N=24) depressive personality disorder were characterized and compared in terms of those variables. RESULTS: Although depressive personality disorder and dysthymia co-occurred in some subjects, 63% of subjects with depressive personality disorder did not have dysthymia, and 60% did not have current major depression. Although subjects with depressive personality disorder were more likely than the mood disorder comparison group to have another personality disorder, 40% had no such disorder. Contrary to study hypotheses, mood disorder was not more common in first-degree relatives of subjects with depressive personality disorder than in relatives of the comparison group. Subjects with and without depressive personality disorder had similar rates of past treatment with medication and psychotherapy; however, the duration of psychotherapy was significantly longer for subjects with than for those without depressive personality. The depressive personality diagnosis was relatively stable over the 1-year follow-up period. CONCLUSIONS: Depressive personality disorder appears to be a relatively stable condition with incomplete overlap with axis I mood disorders and personality disorders. Further studies are needed to better characterize its treatment response and relationship to axis I mood disorders.  相似文献   

17.
The American College of Sports Medicine (ACSM) equation for estimating oxygen consumption (VO2) is often inappropriately applied to non-steady-state treadmill exercise. Therefore, it was the purpose of this investigation to develop an equation to estimate VO2 that could be applied to non-steady-state treadmill exercise in a population of patients with osteoarthritis of the knee, and to assess the generalizability of this equation for estimating VO2peak in patients with cardiovascular disease. Subjects for the investigation were 414 participants in the Fitness and Arthritis in Seniors Trial (FAST), and 362 patients with cardiovascular disease. Results from the FAST subjects showed that the ACSM equation was inappropriate for estimating VO2 during non-steady-state incremental treadmill walking. We developed the following equation (FAST) using speed and the interaction between speed and grade as the predictor variables during treadmill walking: VO2(ml.kg-1.min-1) = 0.0698 x speed(m.min-1) + 0.8147 x grade(%) x speed(m.min-1) + 7.533 ml.kg-1.min-1 The generalizability of the FAST equation for estimating VO2peak was evaluated in the patients with cardiovascular disease. The measured VO2peak of these patients was 23.7 +/- 0.3 ml.kg-1.min-1, whereas the VO2peak values estimated from the FAST equation and the ACSM equation were 24.1 +/- 0.3 and 33.2 +/- 0.5 ml.kg-1.min-1, respectively. No significant differences were found between the measured VO2peak and that estimated from the FAST equation. The VO2peak estimated from the ACSM equation was significantly greater than the measured VO2peak. These results suggest it is more appropriate to use the FAST equation rather than the ACSM equation to estimate VO2 in older patients with either osteoarthritis of the knee or cardiovascular disease.  相似文献   

18.
OBJECTIVE: The tolerability of clonazepam in geropsychiatric inpatients was examined in patients with and without a diagnosis of dementia. DESIGN: Forward-looking retrospective study comprising consecutive patients placed on clonazepam. SETTING: A geropsychiatry unit of a large Veterans Affairs Medical Center. PATIENTS: All geropsychiatry inpatients placed on clonazepam over a 21-month period of time. MEASURE: Mini-Mental State Examination, Brief Psychiatric Rating Scale, Cohen-Mansfield Agitation Inventory and the Rating Scale for Side Effects were performed at admission and discharge as part of an ongoing database. RESULTS: Twenty-four geropsychiatric inpatients were treated with clonazepam (mean dose of 1.2 mg for a minimum of 2 weeks) during the 21 months studies. About one half of the patients had a primary diagnosis of dementia and the remainder had a diagnosis of an affective or psychotic disorder. Two of these patients were discontinued because they had responded to the acute need for clonazepam and a third patient was discontinued because of the development of sedation and confusion. For the remaining 21 patients, scores improved significantly on the Brief Psychiatric Rating Scale (p = 0.017), the Cohen-Mansfield Agitation Inventory (p = 0.011), the Rating Scale for Side Effects (0.004) and the Global Assessment of Functioning (p < 0.000), with no differences in amount of improvement between demented and non-demented patient groups. Scores on the Mini-Mental State Examination remained unchanged. CONCLUSIONS: Clonazepam shows promise as a benzodiazepine with good tolerability in the elderly.  相似文献   

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1. An anatomical peculiarity allows the hand to be positioned so that the terminal phalanx of the middle finger cannot be moved by voluntary effort. When positioned in this way only joint and cutaneous mechanisms subserve position sense. By altering the position of the hand the muscles are again engaged and able to move the finger. Moving the joint then also excites muscular afferents. 2. The position sense of twelve subjects was assessed with and without engagement of the muscles at the joint. Three tests were used in which either angular displacement, angular velocity or duration of displacement were held constant. 3. When muscular attachment was restored, performance in all tests was greatly enhanced. As engagement of the muscles caused little change in the 'stiffness' of the joint, it is unlikely that the improved performance resulted from increased discharges from the joint receptors. Cutaneous mechanisms are unlikely to mediate this improvement as they are likely to have been unaffected by engagement of muscles. It is concluded that intramuscular receptors are partly responsible for normal position sense. 4. In seven of the twelve subjects the test finger was anaesthetized to isolate the contribution of intramuscular receptors. This muscle sense was variable. In some subjects it provided accurate kinaesthetic information but in others the information was crude. If with the test finger anaesthetized subjects exerted voluntary tension with the muscles that move the joint the muscle sense was improved.  相似文献   

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