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71.
ATM missense variant P1054R predisposes to prostate cancer.   总被引:2,自引:0,他引:2  
BACKGROUND: Prostate cancer is associated with defective DNA strand break repair after DNA damage leading to genetic instability and prostate cancer progression. The ATM (ataxia-telangiectasia mutated) gene product is known to play an important role in cell cycle regulation and maintenance of genomic integrity. We investigated whether the prevalence of the ATM missense substitution P1054R is increased in a hospital-based series of prostate cancer patients and whether carriers are at increased risk for treatment-related side effects. MATERIALS AND METHODS: A consecutive series of 261 patients treated for early-stage prostate cancer with I-125 brachytherapy (permanent seed implantation) between 10/2000 and 04/2006 at our institution and a comparison group of 460 male control individuals were screened for the presence of the P1054R variant. Outcome of therapy regarding morbidity was assessed prospectively and compared between carriers vs. non-carriers with the International Prostate Symptom Score (IPSS), a Quality-of-Life-index (QoL) and the International Index of Erectile Function (IIEF-15) with its subgroups (IIEF-5 and EF). RESULTS: The proportion of carriers of the P1054R variant was significantly higher among prostate cancer patients than in the general population (25 out of 261 vs. 22 out of 460; OR 2.1; 95% CI 1.2-3.8, p<0.01). A subgroup of the carriers additionally harboured the ATM missense variant F858L that was associated with a similar risk (OR=2.2; 95% CI 1.1-4.6; p=0.03). After a mean follow-up of 18 months there were no statistically significant differences regarding IPSS (p=0.48), QoL (p=0.61), IIEF-15 score (p=0.78), IIEF-5 score (p=0.83), and EF score (p=0.80), respectively. CONCLUSIONS: The ATM missense variant P1054R confers an about twofold increased risk for prostate cancer in our series. The subgroup of patients with the second-site variant F858L is not at significantly higher risk. After 18 months, there was no evidence for an increased adverse radiotherapy response in P1054R carriers.  相似文献   
72.
BACKGROUND AND PURPOSE: Women carrying mutations in the CHEK2 gene are at an increased breast cancer risk. Data about outcome and prognosis for these patients after standard multimodality treatment are scarce at present. MATERIALS AND METHODS: One-hundred and fifty (150) patients with non-metastasized early-stage breast cancer (T1-2) receiving postoperative radiotherapy following breast-conservative surgery at our department were included in this analysis. Carriers were identified using mutation-specific restriction enzyme-based screening assays in previous investigations. Twenty-five breast cancer patients were heterozygous for one of three CHEK2 gene mutations (I157T, n=13; 1100delC, n=10; IVS2+1G>A, n=2). The comparison group consisted of 125 early-stage breast cancer patients without a CHEK2 gene mutation (non-carriers). Median follow-up was 87 months for the total cohort of patients. RESULTS: Local recurrences occurred in 13 patients (carriers, 3 (12%); non-carriers, 10 (8%)) and distant metastases occurred in 27 patients (carriers, 8 (32%); non-carriers, 19 (15%)). Twenty-five patients had deceased (carriers, 8 (32%); non-carriers, 17 (14%)) with all but 3 deaths related to breast cancer. Actuarial 7-year local relapse-free survival was 86% in carriers versus 90% in non-carriers (p=0.48). Actuarial metastasis-free, disease-free and overall survival at 7 years were 64% vs. 84% (p=0.045), 59% vs. 78% (p=0.07) and 69% vs. 87% (p=0.10), respectively. In a multivariate step-wise Cox regression analysis presence of a CHEK2 mutation remained a borderline significant discriminator for metastasis-free survival (p=0.048; OR=0.4; 95% CI 0.2-1.0) next to T-stage (p=0.001; OR 0.3; 95% CI 0.1-0.6). CONCLUSIONS: Heterozygosity for a germline CHEK2 mutation appears to represent an adverse prognostic factor in patients with early-stage breast cancer. If confirmed in larger studies these data may serve as a basis for future surveillance and treatment strategies taking into account individual germline mutational status.  相似文献   
73.
Objective The pharmacist-run national German drug information service (DIS) has operated since 1988. Answering a steadily increasing demand over the past decade, our centre has, in total, provided information in more than 14,000 cases, mainly for community pharmacists. Information on user’s satisfaction and on possible direct or indirect benefits for patients is as yet scarce. Our objectives were to assess user’s satisfaction with the DIS and to identify any patient-related benefits based on the user’s judgment. Setting Independent national drug information centre at ABDA headquarters. Method A questionnaire was developed, pre-tested, optimized, and used in daily practice over a period of one year (09/2003–08/2004). The questionnaire comprised seven items, aimed only at inquiries which pertained to a patient-related issue. Results During the study period, a total of 1,639 inquiries were answered. Of these, 1,017 (62%) were eligible. The response rate was 45% (455/1,017). Ratings (1 = poor to 5 = very good, mean ± SD) showed positive evaluations for professional quality of advice␣(4.7 ± 0.5), clarity/understandability of advice (4.7 ± 0.5), timeliness of response (4.6 ± 0.7), and helpfulness regarding counselling patients and/or physicians (4.6 ± 0.6). Potential patient benefits could be identified in 42% of the cases that were available to follow-up (190/455). Conclusion This evaluation showed high satisfaction among users of a nationwide DIS, based on quality, understandability, timeliness, and helpfulness regarding counselling. According to its users, DIS was also able to provide positive patient outcomes. Presented in part at the 2nd International Joint Congress of Clinical Pharmacy of the American College of Clinical Pharmacy (ACCP) and the European Society of Clinical Pharmacy (ESCP), Paris, France, April 28–30, 2004, and at the Joint Meeting of the German (DPhG), Austrian (?PhG), and Czech Pharmaceutical Societies, Regensburg, Germany, October 6–9, 2004.  相似文献   
74.
Pulse oximetry is a valuable, noninvasive technique for assessing oxygen saturation that has gained wide clinical acceptance despite little available information concerning normal values in the newborn, especially at an altitude different than sea level. We performed serial pulse oximetry studies on 150 term, appropriate-weight-for-gestational-age, clinically healthy infants at an altitude of 1610 m (5280 ft) at 24 to 48 hours, 1 month, and 3 months of age to define a reference range for oxygen saturation as a guideline in clinical care. We found that mean oxygen saturation at 24 to 48 hours of age is 92% to 93% and varies little with infant activity. With increasing postnatal age, there is a tendency for increased oxygen saturation during the awake states to 93% to 94%, while oxygen saturation during sleep stays the same or even decreases slightly. The lower end of the reference range (2 SDs below the mean) is as low as 85% during feeding at 24 to 48 hours of age, and as low as 86% during quiet sleep at 1 and 3 months of age, with 88% to 89% the lower limit in other activities at all ages.  相似文献   
75.
To assess the cost of and parental response to home oxygen therapy in the newborn, a telephone survey was conducted of 34 families of infants discharged from our intensive care nursery along with supplemental oxygen therapy. Mean birth weight was 1988 g and gestational age was 33 weeks. The mean length of time oxygen was required at home was 74 days. Savings were estimated for each infant and were found to average $33,370. The typical problems encountered by these families are described. Despite the inconveniences involved, 94% of these families stated they would again take a baby home while oxygen dependent if necessary.  相似文献   
76.
Radiologic maxillary sinusitis is an important risk factor for development of bronchopneumonia in mechanically ventilated patients. Nitric oxide produced within the paranasal sinuses is considered to provide an antibacterial environment and to modulate mucociliary clearance function. We hypothesized that a reduced formation of nitric oxide might contribute to the compromised local host defense in radiologic maxillary sinusitis and measured nitric oxide levels directly within maxillary sinuses of septic patients with radiologic maxillary sinusitis (n = 11), whose sinuses were fenestrated to eliminate a possible septic focus. Data were compared with those of patients without airway inflammation (n = 11, control subjects). Despite local inflammation and infection, we found considerably lower maxillary nitric oxide levels than in control subjects (31 +/- 10 versus 2554 +/- 385 parts per billion, mean +/- standard error of the mean, p < 0.001). Consistently, immunohistochemical and in situ hybridization investigations revealed strongly reduced expression of inducible nitric oxide synthase. By applying ultrastructural immunolocalization, we identified cilia and microvilli of the maxillary sinus epithelium as the major nitric oxide production site in control subjects. Our findings provide evidence of markedly reduced nitric oxide production in maxillary sinuses of patients with radiologic maxillary sinusitis and sepsis, implicating impaired local host defense and an increased risk for secondary infections.  相似文献   
77.
PURPOSE: To find a potential prognostic marker of the induction of hydronephrotic atrophy in congenital hydronephrosis we investigated whether the messenger (m)RNA expression and urinary concentration of monocyte chemoattractant protein-1 (MCP-1) correlated with the degree of partial ureteral obstruction, and subsequent hydronephrotic atrophy and interstitial fibrosis. MATERIALS AND METHODS: We created left partial ureteral obstruction in 96 juvenile Wistar rats and complete ureteral obstruction in 18, while 16 underwent sham operation. Depending on excretion of contrast medium into the renal pelvis after 3 days we defined 2 degrees of hydronephrosis. Renal mRNA expression of MCP-1, and renal pelvic and bladder urinary concentrations of MCP-1 were measured after 1, 2 and 3 weeks, and compared with the degree of hydronephrotic atrophy. RESULTS: Grade 1 partial ureteral obstruction resulted in mild histological changes. Grade 2 partial and complete obstruction resulted in significant hydronephrotic atrophy. MCP-1 mRNA expression in the kidney remained unchanged in grade 1 partial obstruction but was moderately increased in grade 2 partial obstruction and clearly over expressed in complete ureteral obstruction. The renal pelvic urinary concentration of MCP-1 was not higher in rats with grade 1 partial obstruction than in sham operated animals but it was significantly increased in those with grade 2 partial and complete obstruction. CONCLUSIONS: mRNA expression and the urinary concentration of MCP-1 correlate with the degree of obstruction and subsequent renal damage in hydronephrosis. They may serve as prognostic markers in children with congenital hydronephrosis.  相似文献   
78.
Background. Hybrid revascularization (HyR), combining minimally invasive left internal mammary artery (LIMA) bypass grafting to the left anterior descending coronary artery (LAD) and catheter interventional treatment of the remaining coronary lesions, avoids the disadvantages associated with cardiopulmonary bypass (CPB). We investigated the clinical follow-up of 57 patients with multivessel disease undergoing this procedure in the last 4 years.

Methods. Between January 1997 and January 2001, 57 consecutive patients (41 men and 16 women, aged 65.7 ± 7.9 years) with coronary artery disease (two-vessel, n = 34; three-vessel, n = 23) were treated with off-pump LIMA-to-LAD bypass combined with balloon angioplasty and stenting of the remaining significantly obstructed (> 50%) coronary vessels. Clinical follow-up data included a early postoperative and a 6-month control angiography and a patient interview in January 2001.

Results. All patients underwent LIMA-to-LAD bypass-grafting and balloon angioplasty in 72 coronary lesions without procedural-related complications. However, one early LIMA bypass occlusion was documented during coronary angiography. Postoperatively no deterioration of preexistent organ dysfunction was observed in any patient. The mean follow-up was 100.7 ± 37.9 weeks in 55 of 57 patients (97%). Control angiography 6 months after HyR (n = 34) revealed a patent LIMA bypass in 33 patients and 8 in-stent restenoses (> 50%) in the coronary arteries that were treated interventionally by re-PTCA (n = 6) or by conventional CABG (n = 1). In 1 patient medical treatment resulted in significant reduction of angina so no further intervention was considered necessary. After HyR 1 patient died 18 months later of an intracerebral hemorrhage. All other patients are alive and doing well.

Conclusions. Our results indicate that in selected patients with multivessel disease including left main stem stenosis HyR is an effective and secure procedure with excellent early and good midterm results. Especially elderly patients with severe concomitant diseases appear to benefit from this approach by avoiding CPB.  相似文献   

79.
Large-field torsional optokinetic stimulation is known to affect the perceived direction of gravity with verticality judgements deviating towards the direction of visual stimulus rotation. The present study aimed to replicate this effect and to examine it further by subjecting participants to optokinetic stimulation in roll, resulting in spontaneous alternations between the perception of object-motion and that of contradirectional self-motion (vection), as reported by the subjects. Simultaneously, subjects were oscillated laterally in a flight simulator and indicated their perception of postural verticality. Results confirmed that rotation of the visual environment in the frontal plane biases the perceived orientation of gravity towards the direction of visual stimulus motion. However, no differential effect of perceptual state on postural verticality was obtained when contrasting verticality judgements made during the perception of object-motion with those obtained during reported self-motion perception. This finding is likely to reflect a functional segregation of central nervous visual-vestibular subsystems that process the perception of self-tilt and that of self-rotation to some degree independently.  相似文献   
80.
BACKGROUND: Preneoplastic and neoplastic lesions of the liver are suspected to arise as a result of estrogen treatment. Here we present the first report on the modulational effects of the steroids 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) on oncogene MDM2 in human hepatocytes. MATERIALS AND METHODS: Collagen-embedded cultures of hepatocytes stimulated with different E2/EE2 concentrations were analyzed by immunocytochemistry, RT-PCR and sequencing for MDM2 protein/mRNA expression, MDM2 mRNA splicing and MDM2 gene mutation. RESULTS: The hepatocytes responded to stimulation with steroid E2/EE2 concentrations from 1-100 nmol/l with the overexpression of MDM2 protein while non-stimulated cells were negative. Stimulation with 1 nmol/l E2 and 10-100 nmol/l EE2 induced MDM2 splicing variants. Hepatocytes treated with 100 nmol/l E2 contained full-length MDM2 mRNA carrying a new type of MDM2 gene mutation. Unstimulated hepatocytes revealed neither mRNA splicing nor alteration of the MDM2 genes. CONCLUSION: The data show that steroid hormones are involved in the induction of MDM2 alterations in benign human hepatocytes. We speculate that some of the alterations may influence MDM2 function, thus possibly favouring genesis of liver changes.  相似文献   
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