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51.
Mahon NG Hedman AE Padula M Gang Y Savelieva I Waktare JE Malik MM Huikuri HV McKenna WJ 《European journal of heart failure》2002,4(2):151-158
BACKGROUND AND AIM: asymptomatic relatives of patients with familial dilated cardiomyopathy who have left ventricular enlargement [LVE] are at risk for progression to dilated cardiomyopathy. A novel index of the fractal correlation properties of heart rate variability (HRV), the short-term scaling component (proportional, variant(1)) in detrended fluctuation analysis, is a promising prognostic tool in left ventricular dysfunction. The aim of this study was to compare values of proportional, variant(1) and conventional HRV indices in LVE relatives with dilated cardiomyopathy patients and normal controls. METHODS: time-domain and spectral HRV measures, and the short-term scaling component ( proportional, variant(1)) were assessed from 24-h Holter recordings from 22 LVE relatives (left ventricular end-diastolic dimension >112% predicted, normal fractional shortening), 24 dilated cardiomyopathy patients and 14 controls. RESULTS: the time domain index SDNN was lower in dilated cardiomyopathy patients [101.8(+/-44.0)] than in LVE relatives [161.7(+/-53.9)] or controls [152.9(+/-51.4)], P=0.01. Similarly, triangular index and spectral measures were reduced in dilated cardiomyopathy patients but not in LVE relatives or controls. In contrast, the short term scaling component ( proportional, variant(1)) in detrended fluctuation analysis was reduced in both dilated cardiomyopathy patients [1.06(+/-0.33)] and in LVE relatives [1.15 (+/-0.20)], compared with controls [1.32(+/-0.16)], P=0.01. Among DCM patients the short-term scaling component ( proportional, variant(1)) was significantly associated with echocardiographic deterioration during follow-up (3.7+/-2.1 year) (P=0.004). CONCLUSION: the short-term scaling component ( proportional, variant(1)) is reduced in asymptomatic relatives of dilated cardiomyopathy patients who have LVE. 相似文献
52.
Expression of von Hippel-Lindau tumor suppressor and tumor-associated carbonic anhydrases Ⅸ and Ⅻ in normal and neoplastic colorectal mucosa 总被引:1,自引:0,他引:1
53.
People live longer than ever before, and the rapidly growing population of the oldest-old are increasingly frequent users of health care services. To determine the extent and causes of hospital care in the population aged 90, we examined the hospital discharge registers for the annual cohorts of Tampere residents born in 1907-1910 at age 90. The basic population consisted of 1077 people, 20.6% of who were men and 79.4% women. Close on one-fifth or 18.7% of this group died during the year under review. During this year, 43.2% of men and 50.3% of women had been admitted to hospital. Men spent significantly fewer days in hospital than women: the mean length of stay for men was 19 days, for women 46 days. Of the 90-year olds, 6.7% were permanently staying in hospitals. The most common diagnoses at discharge were cardiovascular diseases, infections, psychiatric diseases including dementia, and trauma. Of those who had been admitted to hospital once or more within the year, 31.7% died during the follow-up time, while the figure for those not admitted was only 6.2%. People aged 90 are an important group of hospital users. In the future, hospitals need to be prepared to provide adequate care for the most common diseases affecting the growing population of the oldest-old. 相似文献
54.
Sustained cardiomyocyte apoptosis and left ventricular remodelling after myocardial infarction in experimental diabetes 总被引:17,自引:0,他引:17
Bäcklund T Palojoki E Saraste A Eriksson A Finckenberg P Kytö V Lakkisto P Mervaala E Voipio-Pulkki LM Laine M Tikkanen I 《Diabetologia》2004,47(2):325-330
Aims/hypothesis Diabetes is known to reduce survival after myocardial infarction. Our aim was to examine whether diabetes is associated with enhanced cardiomyocyte apoptosis and thus interferes with the post-infarction remodelling process in myocardium in rat.Methods Four weeks after intravenous streptozotocin (diabetic groups) or citrate buffer (controls) injection, myocardial infarction was produced by ligation of left descending coronary artery. Level of cardiomyocyte apoptosis was quantified by TUNEL and caspase-3 methods. Collagen volume fraction and connective tissue growth factor were determined under microscope. Left ventricular dimensions were evaluated by echocardiography and planimetry.Results The number of apoptotic cardiomyocytes was equally high in diabetic and non-diabetic rats after 1 week from infarction. At 12 weeks after infarction the number of apoptotic cells was higher in the diabetic as compared to non-diabetic rats both in the border zone of infarction and in non-infarcted area. Correspondingly, left ventricular end diastolic diameter, relative cardiac weight, connective tissue growth factor-expression and fibrosis were increased in diabetic compared with non-diabetic rats with myocardial infarction.Conclusion/interpretation Sustained cardiomyocyte apoptosis, left ventricular enlargement, increased cardiac fibrosis and enhanced profibrogenic connective tissue growth factor expression were detected after myocardial infarction in experimental diabetes. Apoptotic myocyte loss could be an important mechanism contributing to progressive dilatation of the heart and poor prognosis after myocardial infarction in diabetes.Abbreviations STZ
streptozotozin
- MI
myocardial infarction
- CTGF
connective tissue growth factor
- LV
left ventricular
- LVEDD
LV end-diastolic diameter
- BNP
B-type natriuretic peptide 相似文献
55.
Frequency of hereditary nonpolyposis colorectal cancer 总被引:10,自引:0,他引:10
Jukka-Pekka Mecklin M.D. Heikki J. Järvinen M.D. Antti Hakkiluoto M.D. Hannu Hallikas M.D. Kari-Matti Hiltunen M.D. Niilo Härkönen M.D. Ilmo Kellokumpu M.D. Seppo Laitinen M.D. Jari Ovaska M.D. Jukka Tulikoura M.D. Erkki Valkamo M.D. 《Diseases of the colon and rectum》1995,38(6):588-593
PURPOSE: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant cancer syndrome characterized by early onset of colorectal carcinomas (CRC). Recently, two HNPCC genes have been mapped and cloned, one in the short arm of chromosome 2 and another in the short arm of chromosome 3. There has been a major controversy about the frequency of HNPCC. The few estimates available have been based on series selected by age or series representing local area. The purpose of the present study was to design a nonselected, prospective, multicenter study, taking into account the family background and other risk factors of CRC. METHODS: The proportion of HNPCC of all (N=406) CRC cases was evaluated in a prospective multicenter study. Family history and other risk factors were investigated over a 12-month period for all new CRC patients in ten hospitals. These cases constituted 23 percent of all CRCs diagnosed in Finland during the study period. RESULTS: Three (0.7 percent) cases of verified and seven (1.7 percent) cases of suspected HNPCC were identified, following the evaluation of all families with features indicative of susceptibility to cancer. The proportion of identifiable risk factors of CRC was 5.8–7.5 percent (HNPCC, 0.7-2.4 percent; previous CRC, 3.4 percent; ulcerative colitis, 1.0 percent; familial adenomatous polyposis coli, 0.7 percent). CONCLUSION. This prospective multicenter study revealed that the frequency of hereditary colorectal cancer is lower than in some previous studies, when diagnosis is based on extensive pedigree analysis. This result with recent findings of common ancestral founding mutation in Finnish HNPCC families indicates that there may be geographic differences in the occurrence of HNPCC. However, this does not change the fact that identification of HNPCC—perhaps one of the most common inherited diseases identified in humans—has become a question of vital importance now when diagnosis of the syndrome and largescale screening of gene carriers using specific tests are on the horizon.Supported by grants from the Finnish Cancer Society, the Finnish Foundation for Gastroenterological Research, the Sigrid Juselius Foundation, and the Academy of Finland, Helsinki, Finland. 相似文献
56.
BACKGROUND AND AIMS: In a few, earlier, uncontrolled trials, alleviation of chronic pain has been documented by vitamin D supplementation. This randomized double-blind placebo controlled trial addressed the association between pain and vitamin D deficiency and the effects of vitamin D supplementation on pain in institutionalized aged patients. METHODS: 216 long-term care patients were enrolled in Helsinki, Finland. Pain was assessed by three tools: Resident Assessment Instrument (RAI), Discomfort Behavior Scale, and Pain Assessment in Advanced Dementia Scale. Scores for Cognitive Performance Scale (CPS) and other clinical assessments were also collected from the RAI-database. Levels of 25-hydroxyvitamin D (25- OHD) and parathyroid hormone were also determined. Patients in pain (n=202) were randomized into three treatment groups, each receiving 0, 400, or 1200 IU cholecalciferol per day, respectively. Assessments were repeated after six-month vitamin D supplementation. RESULTS: Patients were aged (84.5+/-7.5 yrs), demented (CPS= 4.9+/-1.4, range 1-6), and chronically bedridden. Pain was present in 38.4% to 83.8% of patients depending on assessment tool. Low 25-OHD levels (<50 nmol/L) were very common (98.1%). However, vitamin D deficiency was not associated with pain or pain behavior. The supplementation resulted in a marked increase in 25-OHD levels. However, neither prevalence of painlessness nor pain scores changed significantly after vitamin D supplementation. CONCLUSIONS: We were not able either to show an association between vitamin D deficiency and pain or to observe alleviation of pain by vitamin D supplementation. The independent role of vitamin D in the etiology of pain remains controversial. 相似文献
57.
58.
During prolonged viewing of ambiguous stimuli, such as Necker cubes, sudden perceptual reversals occur from one perceptual interpretation to another. The role of attention in such reversals is not clear. We tested whether perceptual reversals depend on attentional resources by manipulating perceptual load and recording event‐related potentials (ERPs) during intermittent presentation of Necker stimuli. The results did not reveal any influence for perceptual load on the frequency of reversals. The ERPs showed that perceptual load influenced electrophysiological activity over parieto‐central areas in the P1 time window (110–140 ms), but load did not modify the early enhancements of positivity (30–140 ms), which correlated with perceptual reversals at occipito‐temporal sites. We conclude that disambiguation of ambiguous figures is based on early mechanisms that can work efficiently with only a minimal amount of attentional resources. 相似文献
59.
Antti Kulkas Pekka Tiihonen Petro Julkunen Esa Mervaala Juha Töyräs 《Medical & biological engineering & computing》2013,51(6):697-708
Sleep apnea–hypopnea syndrome (SAHS) causes impairment of daytime functions and increases risk of cardiovascular diseases. Apnea–hypopnea index (AHI), currently used for the estimation of the severity of SAHS, does not contain information on the morphology or duration aspects of the breathing cessations and related oxygen desaturations. Longer breathing cessations and deeper desaturations may have more severe consequences than shorter and shallower ones. To address these issues, novel parameters containing information on the duration and morphology of breathing cessations and oxygen desaturations were calculated and evaluated on 160 male patients (40 patients in normal, mild, moderate and severe AHI severity categories). Obstruction and desaturation duration parameters consist of sum of event durations normalized with the total analysed time. Desaturation severity is a sum of desaturation event areas normalized with total analysed time and obstruction severity parameter is a sum of the products of apnea and hypopnea durations and related desaturation areas normalized with total analysed time. The median follow-up time of the patients was 183 months (range 154–215 months). The 40 patients in each category were further divided into subgroups A and B with lowest and highest novel parameter values, respectively. AHI showed no differences between the subgroups. Mortality was increased in subgroups B compared to subgroups A. The correlation of the novel parameters with AHI was only moderate and the parameter values were partially overlapping between the AHI severity categories. This suggests that patients with similar AHI may in fact suffer from SAHS of very different severity. Thus, the present results suggest that the novel parameters could bring new insight to the individual estimation of the severity of SAHS. 相似文献
60.
Tiina A. Jokela Antti Lindgren Kirsi Rilla Edward Maytin Vincent C. Hascall Raija H. Tammi 《Connective tissue research》2013,54(3-4):115-119
Hyaluronan attached to cell surface can form at least two very different structures; a pericellular coat close to plasma membrane and hyaluronan chains coalesced into “cables” that can span several cell lengths. The hyaluronan in cables, induced by many inflammatory agents, can bind leukocytes, whereas that in the pericellular coat does not contribute to leukocyte binding. Therefore, this structural change seems to have a major role in inflammation. In the present study we checked whether cells of squamous epithelium, like epidermal keratinocytes, can form hyaluronan cables and bind leukocytes. In addition, we checked whether hyaluronan synthesis is affected during the induction of cables. Control keratinocytes expressed pericellular hyaluronan as small patches on plasma membrane. But when treated with inflammatory agents or stressful conditions (tunicamycin, interleukin-1β, tumor necrosis factor-α, and high glucose concentration), hyaluronan organization changed into cable-like structures that avidly bound monocytes. Simultaneously, the total amount of secreted hyaluronan was slightly decreased, and the expression levels of hyaluronan synthases (Has1–3) and CD44 were not significantly changed. The results show that epidermal keratinocytes can form cables and bind leukocytes under inflammatory provocation and that these effects are not dependent on stimulation of hyaluronan secretion. 相似文献