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991.
992.
The contribution of Toll-like receptors (TLRs) to phagocytosis of Borrelia burgdorferi has not been extensively studied. We show that bone marrow-derived macrophages (BMDM) from MyD88(-/-) mice or Raw cells transfected with a dominant-negative MyD88 were unable to efficiently internalize B. burgdorferi. Knockouts of TLR2 and TLR9 or knockdown of TLR5 by small interfering RNA produced no defects in phagocytosis of B. burgdorferi. Production of inflammatory cytokines was greatly diminished in MyD88(-/-) BMDM but only partially affected in TLR2(-/-) BMDM or knockdown of TLR5 and unaffected in TLR9(-/-) BMDM. Cytochalasin D reduced cytokine induction, but not to the level of the MyD88(-/-) BMDM. Addition of cytochalasin D to TLR2(-/-) BMDM inhibited inflammatory responses to B. burgdorferi to the level of MyD88(-/-) BMDM, consistent with a role for TLR2 in both recognition of extracellular products and lysosomal sampling by TLR2 after processing of the organism. Cytochalasin D had no impact on cytokine production in cells undergoing TLR5 knockdown. These results suggest that MyD88, but not TLR2, TLR5, and TLR9, is important for the uptake of B. burgdorferi and that MyD88 affects inflammatory responses through both its effects on phagocytosis and its role in transducing signals from TLR2 and TLR5.  相似文献   
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OBJECTIVE: To compare behavioral and other psychosocial factors in patients with diffuse upper limb pain disorder (ULPD) and patients with carpal tunnel syndrome (CTS). METHODS: We compared 37 hospital outpatients with diffuse ULPD with 36 hospital outpatients with CTS, matched by sex, pain intensity, and duration of illness. We assessed psychiatric morbidity by a standardized interview, and both symptoms and personality by self-rated questionnaires. We measured illness behavior by assessing financial benefits and compensation, coping strategies, illness beliefs, treatments received, and 24 hours of monitoring movements of the most affected arm and the body as a whole. RESULTS: There were no significant differences in the prevalence of either current or premorbid psychiatric disorders, personality scores, symptom amplification, disability, or treatments received. Subjects with ULPD had significantly lower self-rated scores for depression, somatic distress, sleep disturbance, and physical fatigue than subjects with CTS, although there were more than normal levels of anxiety, fatigue, and sleep disturbance in both groups. There were no significant differences in the numbers of arm or body movements by day and night. Significantly more ULPD subjects had been involved in litigation, but litigating patients were a minority. CONCLUSION: The primary etiology of endemic diffuse ULPD, presenting in secondary care, is no more psychiatric, psychological, behavioral, or related to personality than is the case with a similarly chronic and painful condition of known pathology. We cannot exclude either a specific role for psychosocial factors at work, or a more general role for psychosocial factors in maintaining disability in patients with chronic pain.  相似文献   
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Our previous studies in ovariectomized ewes have provided direct evidence that FSH secretion is comprised of basal and episodic modes. In those studies, each GnRH pulse coincided with an FSH pulse, but additional FSH pulses were noted. To determine whether non-GnRH-associated pulses of FSH represent a GnRH-independent component of FSH secretion, we determined whether episodic FSH secretion persists after blockade of GnRH action with a GnRH antagonist. Hypophyseal portal and jugular blood was collected from five ovariectomized and six luteal phase ewes at 5-min intervals for 6 h before and 6 h after a single iv injection of Nal-Glu (10 micro g/kg body weight). Hypophyseal portal LH and FSH and jugular patterns of FSH were compared with patterns of GnRH. Before Nal-Glu, in both models, there was a one-to-one concordance between GnRH and portal LH pulses, and each GnRH pulse was associated with a FSH pulse. However, additional non-GnRH-associated pulses of FSH were present. Nal-Glu administration eliminated LH but not FSH pulsatility. Nal-Glu inhibited interaction of GnRH I with GnRH type I receptor but not interaction of GnRH II with type II receptor. These studies provide the first direct evidence of the existence of an acute GnRH I-independent component of episodic FSH secretion.  相似文献   
998.
The genetic determination of left ventricular mass in healthy adults.   总被引:2,自引:0,他引:2  
AIMS: The extent to which left ventricular (LV) mass, an independent cardiovascular risk factor, is determined by genetic factors is unclear. The aim of this study was to assess the heritability of LV mass and its association with three potential candidate genes. METHODS: A population-based adult twin study model was utilized. Echocardiographic assessment of LV mass was performed in 110 twin pairs (mean age 55.9+/-10.9 years). An estimate of genetic determination, heritability, was calculated for the main echocardiographic parameters. The cohort were genotyped for the G-protein beta-3, aldosterone synthase, and beta-1 adrenoceptor genes. RESULTS: The intra-class correlation coefficients for LV mass were 0.69 for monozygotic (r-MZ) twins and 0.32 for dizygotic (r-DZ) twins, P=0.008 (heritability estimate of 0.69). This pattern persisted following correction for known confounding factors. Within-pair differences in the monozygotic, discordant and concordant dizygotic twins showed no differences for the three genes with respect to left ventricular wall thickness or mass. There was a non-significant trend towards a relationship between LV mass and the beta-1 adrenoceptor genotype. CONCLUSION: Within a normal population left ventricular mass has a significant genetic determination. Further investigation of potential candidate genes is required.  相似文献   
999.

Background

Urinary incontinence is a highly prevalent condition in aging women that results in significant morbidity. Less than half of women who suffer from urinary incontinence seek treatment, resulting in a significant proportion of clinically relevant urinary incontinence remaining undiagnosed. Therefore, the purpose of this study was to quantify the prevalence of urinary incontinence in undiagnosed women in a managed care population.

Methods

There were 136,457 women aged 25-80 years enrolled in Kaiser Permanente Northwest who were free of genitourinary diagnoses, including urinary incontinence, who were included in this study. Of the 2118 women who were mailed questionnaires ascertaining information on demographic and urinary incontinence characteristics, 875 completed the survey. A chart review of the 234 women who reported moderate to severe urinary incontinence was performed.

Results

The prevalence of undiagnosed urinary incontinence was 53% in the preceding year, and 39% in the preceding week. The prevalence of undiagnosed stress, mixed, and urge incontinence was found to be 18.7%, 12.0%, and 6.8%, respectively. Quality of life was found to significantly decrease with increasing urinary incontinence severity. Of the 234 chart-reviewed women, 5% were found to have physician-documented urinary incontinence.

Conclusions

These results suggest that a significant proportion of women in this managed care population are suffering from urinary incontinence that remains undiagnosed. Efforts should be made to encourage women and physicians to initiate conversations about urinary incontinence symptoms in order to decrease the unnecessary burden of this disease.  相似文献   
1000.
AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid(GA) against HCT-15 colon cancer cells.METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide(MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species(ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2',7'-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1.RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase(0.98 ± 1.03 vs 58.01 ± 2.05)with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment.CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells.  相似文献   
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