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43.
The effect of race and sleep-disordered breathing on nocturnal BP "dipping": analysis in an older population 总被引:4,自引:0,他引:4
Ancoli-Israel S Stepnowsky C Dimsdale J Marler M Cohen-Zion M Johnson S 《Chest》2002,122(4):1148-1155
STUDY OBJECTIVES: BP normally drops (or "dips") by approximately 10% at nighttime; however, in a number of illnesses there is an increased amount of "nondipping" of nocturnal BP. This study examined whether nondipping in older African Americans and older white subjects is related to the presence of sleep-disordered breathing (SDB) and hypertension. DESIGN: Prospective study with a convenience sample. SETTING: All data were collected in the subjects' homes. PARTICIPANTS: Seventy self-defined African Americans with complaints of snoring or excessive daytime sleepiness, and 70 age-matched and gender-matched white subjects. Measurements and results: Sleep was recorded for 2 nights, with 1 night of oximetry. BP was recorded on a separate 24-h period. African Americans had higher dipping ratios than white subjects even after accounting for covariates such as respiratory disturbance index (RDI), oxygen desaturation index (ODI), body mass index, and average 24-h mean arterial pressure (p = 0.025). Higher values of RDI (R(2) = 0.0686, p = 0.021) and ODI (R(2) = 0.042, p < 0.03) were correlated with higher dipping ratios in both African Americans and white subjects. However, there was a three-way interaction such that higher RDIs were correlated primarily with nondipping in African Americans receiving antihypertensive medication (R(2) = 0.0373, p = 0.022). CONCLUSIONS: These results demonstrated that African Americans tend to be "nondippers," while white subjects tended to be "dippers." This nondipping was not a result of weight, gender, or of having SDB. The analyses also confirmed that, in both races, the dipping ratio was greatest in those with SDB and hypertension. The third hypothesis, that RDI would be greatest in the nondipping hypertensive subjects, was true only for the African Americans. 相似文献
44.
Changes in cognitive function associated with sleep disordered breathing in older people 总被引:1,自引:0,他引:1
Cohen-Zion M Stepnowsky C Marler Shochat T Kripke DF Ancoli-Israel S 《Journal of the American Geriatrics Society》2001,49(12):1622-1627
OBJECTIVES: Sleep disordered breathing (SDB) is very common in older people and is known to be associated with complaints of impaired daily functioning, including excessive daytime sleepiness and cognitive impairments. As part of a larger study on SDB and aging, it became possible to examine the relationship between SDB and cognition in older men and women. DESIGN: A population-based longitudinal study. SETTING: In-home interviews and home sleep recordings in the greater San Diego area. PARTICIPANTS: Community-dwelling people age 65 and older with high risk for SDB were originally studied from 1981 through 1985 and then followed every 2 years. Data from the 46 subjects who completed Visit 3 and Visit 4 are presented. MEASUREMENTS: Subjects were interviewed in the home about their sleep and medical condition before each visit. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Daytime sleepiness was based on self-report. Objective sleep was recorded in the home and scored for sleep, apneas and hypopneas, and oximetry variables. RESULTS: Increases in respiratory disturbance index (RDI) (P= .036) and increases in daytime sleepiness (P= .002) were associated with decreases in cognitive performance (i.e., increases in cognitive impairment). Increases in RDI were also associated with increases in daytime sleepiness (P= .012). Change in MMSE scores was therefore regressed onto changes in RDI, daytime sleepiness, age, and education, resulting in decreases in MMSE scores being associated with increases in daytime sleepiness (P= .019) but not with changes in RDI (P= .515). There was no significant relationship between changes in oxygen saturation levels and changes in MMSE. CONCLUSIONS: The results of this study suggest that declining cognitive function is associated primarily with increases in daytime sleepiness. Although cognitive decline was also associated with increases in RDI, this association did not hold in the more inclusive model which also included variable of SDB, oximetry, sleep and subjective report. One theoretical model could suggest that any relationship between SDB and cognitive function may be mediated by the effect of SDB on daytime sleepiness. These results suggest that older patients suffering from mild to moderate SDB may benefit from the treatment of SDB, even if they are not markedly hypoxemic. 相似文献
45.
The development of cellular immunity to Epstein-Barr virus after allogeneic bone marrow transplantation 总被引:7,自引:10,他引:7
Epstein-Barr virus-induced lymphoproliferative disease (EBV-LPD) is a potentially lethal complication during the first 6 months after allogeneic bone marrow transplantation (BMT). To determine whether deficiencies of EBV-specific cellular immunity contribute to EBV-LPD susceptibility and distinguish patients at risk, we performed limiting dilution analysis to quantify anti-EBV cytotoxic T-lymphocyte precursor (CTLp) frequencies in 26 recipients of unmodified or T-cell-depleted (TCD) grafts from EBV-seropositive donors. At 3 months post-BMT (n = 26), only five patients had EBV CTLp frequencies in the range of seropositive normal controls, irrespective of the type of transplant administered. By 6 months post-BMT, 9 of 13 patients tested had EBV CTLp frequencies within the normal range. The time period in which these patients had deficient cellular immunity to EBV corresponds to the period in which we have observed EBV-LPD in most prior patients. One patient with a low EBV CTLp frequency at 4 months post-BMT developed an EBV-LPD. Within 2 weeks of receiving an infusion of donor peripheral blood mononuclear cells (PBMC) providing less than 1,200 EBV- specific cytotoxic T-cell precursors, populations of EBV-specific CTL in the circulation were restored to levels detected in normal seropositive adults. Concurrently, the patient achieved a regression of the EBV-LPD, which has been sustained without further therapy. These studies indicate that recipients of both unmodified and TCD marrow grafts have profound deficiencies of EBV-specific T cell-mediated immunity early posttransplant, and that the period of risk for EBV-LPD closely corresponds to this interval of severe deficiency. Treatment of one patient with EBV-LPD with marrow donor-derived PBMC induced a rapid expansion of EBV-specific cytotoxic T-cell populations that occurred contemporaneously with the clinical regression of disease. 相似文献
46.
Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell-cell adhesion molecule that is expressed on circulating platelets, on leukocytes, and at the intercellular junctions of vascular endothelial cells and mediates the interactions of these cells during the process of transendothelial cell migration. The cDNA for PECAM-1 encodes an open reading frame of 738 amino acids (aa) that is organized into a 27- aa signal peptide, a 574-aa extracellular domain composed of 6 Ig homology units, and a relatively long cytoplasmic tail of 118 aa containing multiple sites for posttranslational modification and postreceptor signal transduction. To provide a molecular basis for the precise evaluation of the structure and function of this transmembrane glycoprotein, we have determined the organization of the human PECAM-1 gene. The PECAM-1 gene, which has been localized to human chromosome 17, is a single-copy gene of approximately 65 kb in length and is broken into 16 exons by introns ranging in size from 86 to greater than 12,000 bp in length. Typical of other members of the Ig superfamily, each of the extracellular Ig homology domains is encoded by a separate exon, consistent with PECAM-1 having arisen by gene duplication and exon shuffling of ancestral Ig superfamily genes. However, the cytoplasmic domain was found to be surprisingly complex, being encoded by seven short exons that may represent discrete functional entities. Alternative splicing of the cytoplasmic tail appears to generate multiple PECAM-1 isoforms that may regulate phosphorylation, cytoskeletal association, and affinity modulation of the mature protein. Finally, a processed pseudogene having 76% identity with PECAM- 1 cDNA was identified and localized to human chromosome 3. These findings should have important implications for structure/function analysis of PECAM-1 and its role in vascular adhesive interactions. 相似文献
47.
RJ Mascarenhas ND Hapangama PJ Mews A Burlakoti S Ranjitkar 《Australian dental journal》2019,64(1):106-110
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain. 相似文献
48.
美国国立神经疾病和卒中研究所-加拿大卒中网血管性认知障碍统一标准 总被引:20,自引:11,他引:9
Ron C.Petersen Sandra E.Black Charles DeCarli Jose G.Merino Raj N.Kalaria Harry V.Vinters Martin Dichgans John R.Marler 李焰生 俞羚 高枚春 张静芳 熊昕丽 邹静 林岩 潘元美 《国际脑血管病杂志》2007,15(1):4-24
背景和目的:1/3的个体会罹患卒中和(或)痴呆,而且,除卒中或痴呆外,2倍于此数的人会出现认知障碍。常用的卒中量表并不能评价认知功能,而痴呆的诊断标准则集中在认知障碍的晚期阶段,且在很大程度上偏向Alzheimer病(AD)的诊断。尚缺乏普遍公认的标准用于识别和描述存在认知障碍的个体,尤其是在早期阶段,而且特别是与血管因素有关的认知障碍或血管性认知障碍。方法:美国国立神经疾病和卒中研究所(MINDS)与加拿大卒中网(CSN)召集临床诊断、流行病学、神经心理学、脑影像学、神经病理学、试验模型、生物标记物、遗传学和临床试验方面的研究人员,为血管性认知障碍的描述和研究推荐一些最低限度的常用的临床和研究标准。结果:将这些讨论的结果发表于此。结论:一个统一标准的制定代表着使用、确认和改进过程中的第一步。使用相同的标准将有助于在认知障碍的早期阶段识别患者,使不同的研究具有可比性,并且通过整合知识来加速研究进展的步伐。 相似文献
49.
The twin concepts of normalisation (Wolfensberger, 1972) and care in the community (DHSS, 1981) have been the spurs to increased opportunities being given to people with mental handicaps to learn about sexuality. Too often these opportunities are provided as part of personal hygiene programmes or are based on child-oriented materials. Little thought has yet been given to developing appropriate models of teaching which offer an all-round approach, are geared to adults, take into account people's special learning difficulties, and put sexuality in the context of relationships, growing up, and other life events. This is the report of a multidisciplinary approach to help prepare some adults with mental handicaps, residing in a Chichester mental handicap hospital, for life in the community. Emphasis was placed on looking at sexuality and relationships in the context of life events. 相似文献
50.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described. 相似文献