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61.
Stoner MC Cambria RP Brewster DC Juhola KL Watkins MT Kwolek CJ Hua HT LaMuraglia GM 《Journal of vascular surgery》2005,41(6):223-949
BACKGROUND: Reoperative carotid endarterectomy (CEA) is an accepted treatment for recurrent carotid stenosis. With reports of a higher operative morbidity than primary CEA and the advent of carotid stenting, catheter-based therapy has been advocated as the primary treatment for this reportedly "high-risk" subgroup. This study reviews a contemporary experience with reoperative CEA to validate the high-risk categorization of these patients. METHODS: From 1989 to 2002, 153 consecutive, isolated (excluding CEA/coronary artery bypass graft and carotid bypass operations) reoperative CEA procedures were reviewed. Clinical and demographic variables potentially associated with the end points of perioperative morbidity, long-term durability, and late survival were assessed with multivariate analysis. RESULTS: There were 153 reoperative CEA procedures in 145 patients (56% men, 36% symptomatic) with an average age of 69 +/- 1.3 years. The average time from primary CEA (68% primary closure, 23% prosthetic, 9% vein patch) to reoperative CEA was 6.1 +/- 0.4 years (range, 0.3 to 20.4 years). At reoperation, patch reconstruction was undertaken in 93% of cases. The perioperative stroke rate was 1.9%, with no deaths or cardiac complications. Other complications included cranial nerve injury (1.3%) and hematoma (3.2%). Average follow-up after reoperative CEA was 4.4 +/- 0.3 years (range, 0.1 to 12.7 years), with an overall total stroke-free rate of 96% and a restenosis rate (>50%) by carotid duplex of 9.2%. Among variables assessed for association with restenosis after reoperative CEA, only younger age was found to be significant (66 +/- 2.5 years vs 70 +/- 0.7 years, P < .05). The all-cause long-term mortality rate was 29%. Multivariate analysis of long-term survival identified diabetes mellitus as having a negative impact (hazard ratio, 3.4 +/- 0.3, P < .05) and lipid-lowering agents as having a protective effect (hazard ratio, 0.42 +/- 0.4, P < .05) on survival. CONCLUSION: Reoperative CEA is a safe and durable procedure, comparable to reported standards for primary CEA, for long-term protection from stroke. These data do not support the contention that patients who require reoperative CEA constitute a "high-risk" subgroup in whom reoperative therapy should be avoided. 相似文献
62.
Lee T. Ferris James S. Williams Chwan Li Shen Kendra A. O'Keefe Kimberly B. Hale 《Journal of Sports Science and Medicine》2005,4(3):354-360
Older individuals, as a group, tend to experience difficulty sleeping compared to younger adults. Improving sleep in the elderly would have beneficial public health consequences. This study utilized 8 sedentary, older adults, 78.1 ± 3.1 years of age, who participated in a six-month long resistance training (RT) program. The Pittsburgh Sleep Quality Index (PSQI) was used to examine sleep quality, and a 1 repetition max test (1-RM) was used to determine upper (bench press) and lower (leg press) body strength. Total strength, defined as the sum of the bench press and leg press 1-RM results, was also reported. The training resulted in significant improvements (p < 0.05) in total (19%) and upper body (52%) strength and in sleep quality (38%). Future studies should examine the effects of strength gain/loss and time-of-day training on sleep quality.
Key Points
- Compromised sleep and deterioration of skeletal muscle mass and function are commonly found among the aged.
- Results show that RT led to improvements in upper and total body strength in older participants who trained three times per week in the morning.
- The resistance training led to improvements in sleep as measured by a self-report sleep questionnaire, the Pittsburgh Sleep Quality Index.
- The small sample size used, lack of control group, and the fact that the participants on average were characterized as “good ”sleepers at the study onset, necessitates that further investigation occur.
- We suggest that further research is required to explore the effects of RT performed at different times of the day as well as to determine the relationship between sleep gains or losses upon changes in sleep quality.
63.
64.
Colt JS Wacholder S Schwartz K Davis F Graubard B Chow WH 《Annals of epidemiology》2005,15(9):700-704
PURPOSE: Participants in epidemiology studies are often asked to complete an interview and to provide biospecimens. In a population-based case-control study of kidney cancer involving an interview and optional biospecimens, we examined whether mentioning the biospecimens in the initial contact letter adversely affects willingness to be interviewed. METHODS: Eligible cases (n = 434) and controls (n = 775) in Detroit were alternately assigned to receive one of two versions of the contact letter. Both explained that the study involves an interview with 100 dollars compensation plus an optional component with additional compensation; only one disclosed that the optional component involved biospecimens. RESULTS: There were no meaningful differences between the groups in willingness to be interviewed. However, among 303 cases and 351 controls already interviewed, the proportion providing biospecimens was higher in the fully informed group: for blood, the differences were 10.8 (95% CI, 2.0, 19.5) for cases and 6.7% (95% CI, -1.7, 15.1) for controls. Findings were similar for saliva. CONCLUSIONS: In a study involving an interview and optional biospecimens, informing people about the samples in the contact letter seems preferable to a non-specific reference to a second study component. Both approaches yielded similar interview participation rates, but biospecimen participation rates were higher among those informed about the samples in the contact letter. 相似文献
65.
66.
Mitochondrially targeted vitamin E and vitamin E mitigate ethanol-mediated effects on cerebellar granule cell antioxidant defense systems 总被引:2,自引:0,他引:2
Siler-Marsiglio KI Pan Q Paiva M Madorsky I Khurana NC Heaton MB 《Brain research》2005,1052(2):202-211
Ethanol (EtOH) disrupts the structure and function of the developing nervous system, sometimes leading to birth defects associated with fetal alcohol syndrome (FAS). Animal FAS models indicate that cellular membrane peroxidation, intracellular oxidant accumulation, and suppression of endogenous antioxidant enzymes contribute to the toxic effects of EtOH. Mitochondrially targeted vitamin E (MitoVit E), a chemically engineered form of vitamin E (VE) designed to accumulate in the mitochondria, has been shown to inhibit intracellular oxidant accumulation and cell death more effectively than VE. In previous investigations, we have shown that, in vivo, VE reduces neuronal death in the developing cerebellum of EtOH-exposed animals, and, in vitro, VE prevents apoptotic and necrotic death of EtOH-exposed cerebellar granule cells (CGCs). The present investigation shows that, in a FAS CGC model, 1 nM MitoVit E renders significant neuroprotection against EtOH concentrations as high as 1600 mg/dL. The present study also demonstrates that, in this same model, MitoVit E mitigates EtOH-induced accumulation of intracellular oxidants and counteracts suppression of glutathione peroxidase/glutathione reductase (GSH-Px/GSSG-R) functions, protein expression of gamma-glutamylcysteine synthetase (gamma-GCS), and total cellular glutathione (GSH) levels. In the presence and absence of EtOH, VE amplifies the protein expression levels of gamma-GCS, an enzyme that performs the rate-limiting step for GSH synthesis, and total GSH levels. These results suggest that MitoVit E and VE ameliorate EtOH toxicity through non-oxidant mechanisms-modulations of endogenous cellular proteins-and antioxidant means. 相似文献
67.
The current article describes the application of a behavioral psychotherapy, acceptance and commitment therapy (ACT), to the treatment of post-traumatic stress disorder (PTSD). It is argued that PTSD can be conceptualized as a disorder that is developed and maintained in traumatized individuals as a result of excessive, ineffective attempts to control unwanted thoughts, feelings, and memories, especially those related to the traumatic event(s). As ACT is a therapeutic method designed specifically to reduce experiential avoidance, it may be a treatment that is particularly suited for individuals with PTSD. The application of ACT to PTSD is described, and a case example is used to demonstrate how this therapy can be successfully used with individuals presenting for life problems related to a traumatic event. 相似文献
68.
Takahashi LK Nakashima BR Hong H Watanabe K 《Neuroscience and biobehavioral reviews》2005,29(8):1157-1167
The odors of predators used in animal models provide, in addition to electric footshock, an important means to investigate the neurobiology of fear. Studies indicate that cat odor and trimethylthiazoline (TMT), a synthetic compound isolated from fox feces, are often presented to rodents to induce fear-related responses including freezing, avoidance, stress hormone and, in some tests, risk assessment behavior. Furthermore, we report that different amounts of cat odor impregnated on small-, medium-, or large-sized cloths impact the display of fear-related behavior when presented to rats. That is, rats exposed to a large cat odor containing cloth exhibit an increase in fear behavior, particularly freezing, which remains at high levels in habituation tests administered over a period of 7 days. The large cloth also induces a long-lasting increase in avoidance behavior during repeated habituation and extinction tests. A review of the brain regions involved in predator odor-induced fear behavior indicates a modulatory role of the medial amygdala, bed nucleus of the stria terminalis, and dorsal premammillary nucleus. In addition, the basolateral amygdala is involved in fear behavior induced by cat odor but not TMT, and the central amygdala does not appear to play a major behavioral role in predator odor-induced fear. Future research involving the use of predator odor is likely to rapidly expand knowledge on the neurobiology of fear, which has implications for understanding fear-related psychopathology. 相似文献
69.
INTRODUCTION: Pseudomonas aeruginosa causes serious infections in severely burned patients due to its ability to produce numerous virulence factors. The production of most of these factors is controlled by the cell-to-cell communication system called quorum sensing (QS). We have recently shown that several proinflammatory and hematopoietic cytokines are produced during infection of the burn wound with P. aeruginosa strain PAO1. Most of these cytokines were not produced during either thermal injury or P. aeruginosa infection alone. MATERIALS AND METHODS AND RESULTS: In this study, we tried to determine if the QS systems play a role in the production of cytokines during P. aeruginosa infection of burn wounds. This was accomplished using the murine model of thermal injury, the P. aeruginosa strain PAO1 and its QS defective mutant (PAO-JP2), and the Multi-probe RNase protection assay. The mRNA for TNF-alpha, IL-6, TGF-beta, and G-CSF was detected within the skin of PAO1 infected/thermally injured mice. In contrast, the expression of these cytokines was not detected in PAO-JP2 infected/thermally injured mice. In comparison with the parent strain, PAO-JP2 was not defective either in its growth or in its spread within the thermally injured skin. A complementation experiment, using a plasmid that carries the intact QS gene, was conducted to confirm these results. In the presence of the complementing plasmid, PAO-JP2 produced the mRNA for the above cytokines. CONCLUSIONS: These results suggest that: 1) the QS system is involved in the induction of cytokine expression during P. aeruginosa infection of burn wounds; and 2) this effect may be caused by either a component of the QS system or a QS-controlled virulence factor. 相似文献
70.
Orsillo SM Batten SV Plumb JC Luterek JA Roessner BM 《Journal of traumatic stress》2004,17(3):241-248
Although posttraumatic stress disorder (PTSD) is defined by the experience of intense negative emotions and emotional numbing (American Psychiatric Association, 1994), empirical study of emotional responding in PTSD has been limited. This study examined emotional responding among women with and without PTSD to positive and negative film stimuli across self-reported experience, facial expression, and written expression. Consistent with previous findings, no evidence for generalized numbing was found. In general, women with PTSD exhibited higher levels of negative activation and expressed more negative emotion words to both positive and negative film stimuli, whereas no group differences emerged in facial expressivity. Results are interpreted within the context of the current literature on emotional deficits associated with PTSD. 相似文献