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31.
OBJECTIVES: This open-label canine study assessed whether n-3 polyunsaturated fatty acids (PUFAs) prevent vagally induced atrial fibrillation (AF) and influence atrial tissue expression levels of connexins (CXs). BACKGROUND: n-3 polyunsaturated fatty acids in fish oils protect against sudden cardiac death and reduce postoperative AF. Changes in spatial organization of gap junctions or cellular CX levels have been linked to arrhythmogenesis. METHODS: Vagally induced AF was studied. Eight dogs were given fish oil daily for 14 days. Eight control dogs had reproducibly induced AF and were re-evaluated after intravenous administration of fish oil. Atrial fibrillation was compared, and n-3 PUFA, CX40, and CX43 protein levels were assessed in atrial biopsies. RESULTS: Atrial tissue n-3 PUFA levels increased in oral treatment dogs (5.78 +/- 0.71% vs. 2.49 +/- 0.46% in control animals, p < 0.001). No difference was observed for atrial refractory periods or hemodynamic or electrocardiographic parameters. Incidence of AF in oral treatment dogs decreased 79% with the extra stimulus technique (10.5% vs. 48.9%, p = 0.003) and 42% with burst induction (22.5% vs. 38.8%, p = 0.038). Both CX40 and CX43 levels were lower in oral treatment dogs (60% [p = 0.019] and 42% [p = 0.038] lower, respectively); protection against AF was mostly related to reduced CX40 expression levels (p = 0.02). In dogs that were given intravenous n-3 PUFAs, AF inducibility by the extra stimulus technique was reduced from 75.0% to 28.6% (p = 0.002). CONCLUSIONS: Oral treatment with fish oils increased atrial n-3 PUFA levels and reduced vulnerability to induction of AF in this dog model. Modulation of cardiac CX by n-3 PUFAs probably contributes to the antiarrhythmic effects of fish oils.  相似文献   
32.
The electrogastrogram and its analysis   总被引:1,自引:0,他引:1  
In recent years interest in the electrogastrogram, the EGG, has manifested itself in an increasing number of articles. In this review a brief exposition of the EGG phenomenon is made and the more prominent methods of signal analysis relevant to the EGG are presented and discussed.  相似文献   
33.
To establish the value of breathhold magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis. Over a 14-month period, 138 patients clinically suspected of having appendicitis were evaluated prospectively with MRI and comprised the study group. Fast turbo spin-echo breathhold T1, T2 and T2 fat suppression sequences were used in coronal and axial planes. The imaging results were recorded separately and subsequently correlated with clinical, radiological and histopathological follow-up. The effect of imaging strategies in patients suspected of appendicitis on hospital resources was calculated. Sixty-two of the 138 patients had a histopathologically proven appendicitis. MRI determined appendicitis in 63 patients, with one examination being false positive. The resulting sensitivity and specificity were 100% and 99%, respectively. MRI showed an alternative diagnosis in 41 of the 75 remaining patients. In 22 of the remaining 34 patients, a normal appendix was depicted with MRI. In two patients, where MRI showed no appendicitis, an alternative diagnosis or normal appendix, an unnecessary appendectomy was performed. The overall effect of using MRI in patients suspected of appendicitis on the use of hospital resources could have been a net saving between € 55,746 and € 72,534. MRI has a high accuracy in detecting and excluding appendicitis, an alternative diagnosis or showing the normal appendix, and can be a valuable and cost-effective tool in the workup of patients clinically suspected of having appendicitis.  相似文献   
34.
Three patients of Turkish origin with recurrent abdominal complaints and fever are presented. All had consanguineous parents and two were brothers. Biochemistry and haematology were normal except for a high sedimentation rate. With reference to these patients, some aspects of the diagnosis and the therapeutic approach of familial Mediterranean fever are discussed. In patients of Turkish origin who complain of abdominal pain, familial Mediterranean fever should probably be considered more often.  相似文献   
35.
The latency, the rise time and the influence of the acoustic reflex on sound transmission were investigated in the adult rat during ketamin anesthesia. This was done by recordings of the cochlear microphonics (CM) and electromyographic (EMG) recordings of the reflex responses of the tensor tympani muscle. The acoustic reflex was elicited by contralateral acoustic stimuli of which the intensity and frequency was varied. Ipsilaterally, the effect on sound transmission was determined by estimating the change in amplitude of the CM's of ipsilateral administered subliminal stimuli. It was shown that both the tensor tympani muscle and the stapedius muscle contribute in the reflex. The latency as well as the rise time of the reflex determined by CM recordings showed to be short (minimal values: 12 and 7 ms respectively). The mean latency of the tensor tympani muscle reflex, measured by EMG, was about 7 ms. The attenuation of 0.25-8 kHz tone bursts upto 115 dB SPL is limited to a mean maximum of 15 dB SPL. The maximal attenuation was shown to occur at 1 kHz. Frequencies above 2 kHz appeared to be the best elicitor of the middle ear muscle reflex.  相似文献   
36.
Human papillomavirus type 16 (HPV 16) has been associated with a variety of squamous carcinomas, particularly those involving the anogenital tract. The authors report the development of an oropharyngeal carcinoma in a 43-year-old man approximately 20 months after cardiac transplantation while he was on a maintenance regimen of cyclosporine A and prednisone. The carcinoma was resistant to treatment, and he died of complications related to metastatic disease 3 years posttransplantation. Molecular biologic studies using nonisotopic-labeled viral DNA probes were done. In situ hybridization demonstrated the presence of HPV 16 DNA in the tumor cells. DNA dot blot analysis confirmed the presence of multiple copies of HPV 16 DNA within the tumor cells and their absence from adjacent normal-appearing tissue. Southern blot analysis suggested that the HPV 16 DNA was integrated into the tumor cell genome. With increasing recognition of the carcinogenicity of HPV type 16 infection, a role for this virus in the development of squamous cell malignancies in immunosuppressed organ transplant recipients is likely to be noted with increasing frequency.  相似文献   
37.
Nineteen patients with non-Hodgkin lymphoma of unfavourable histology (15 high grade and 4 intermediate grade) were treated with two new combination chemotherapeutic schemes. Except for one all were partial (8) or complete (10) responders to treatment. Polyamines were measured in every spontaneously voided urine sample. Pretherapeutically all (11) stage III and IV patients had borderline or increased urinary putrescine (Pu) and sum of isoputreanine, spermidine and spermine (sigma Isoputr,Sd,Sp), except for the non-responder. Except for one, all (8) stage I and II patients had normal urinary Pu and sigma Isoputr,Sd,Sp. Posttherapeutically patients with pretherapeutically increased sigma Isoputr,Sd,Sp returned to normal (5), borderline (2), or slightly increased (3) levels. The post-therapeutic achievement of normal or borderline sigma Isoputr,Sd,Sp was not necessarily connected with accomplishment of complete remission. From the start of therapy until clinical restaging, partially or completely responding stage III and IV patients excreted 5-234 mmol sigma Isoputr,Sd,Sp per mol of creatinine above the mean normal value plus 2 SD. For stage I and II patients and the clinical non-responder this parameter amounted to 0-5 mmol/mol of creatinine. Peaks in urinary Pu and sigma Isoputr,Sd,Sp follow-up curves were related in time to the administration of chemotherapeutics. For responding stage III and IV patients the rate of the decrease of sigma Isoputr,Sd,Sp levels paralleled the clinically observed rate of tumour load reduction. This study suggests that notably for non-Hodgkin lymphoma patients with high tumour loads the constant monitoring of polyamines can provide information on pretherapeutic spontaneous tumour cell loss, the efficacy of chemotherapeutic combinations, the kinetics-, and (within certain limitations) the extent of therapeutically induced tumour cell death.  相似文献   
38.
Thalidomide-associated thrombocytopenia   总被引:1,自引:0,他引:1  
OBJECTIVE: To report thrombocytopenia in a patient prescribed thalidomide for multiple myeloma (MM). CASE SUMMARY: A 70-year-old woman was diagnosed in 2003 with MM. At diagnosis, melphalan 0.25 mg/kg/day and prednisolone 2 mg/kg/day were started; however, the patient became refractory to therapy. Melphalan and prednisolone were discontinued, and monotherapy with dexamethasone 40 mg for 12 days per month was started. The patient's hematologic condition deteriorated again after about one year; dexamethasone was discontinued, and treatment with oral thalidomide 200 mg/day was initiated. About 2 weeks after thalidomide administration, the woman developed disabling adverse effects (flu-like symptoms, swollen fingers, rash and hematoma on her legs, shortness of breath, dry mouth, multiple petechiae). Laboratory testing showed neutropenia (neutrophils 0.4 x 10(9)/L) and thrombocytopenia (platelets 58 x 10(9)/L). Thalidomide was promptly discontinued; within 3 weeks, the laboratory values returned to pretreatment levels (1.3 x 10(9)/L and 267 x 10(9)/L, respectively) and her symptoms disappeared. DISCUSSION: Thrombocytopenia is a rarely reported hematologic adverse consequence of thalidomide therapy. A recent report identified 5 patients who developed thrombocytopenia while undergoing monotherapy with thalidomide for MM. According to the Naranjo probability scale, thalidomide was classified as the probable cause of thrombocytopenia in our patient. CONCLUSIONS: Unlike other antineoplastic drugs, thalidomide is rarely reported to cause severe hematologic toxicity. We present this case to increase clinicians' awareness for the potential of thalidomide to adversely affect platelet counts, particularly because its effectiveness in MM will likely result in expansion of its clinical use.  相似文献   
39.
OBJECTIVE--To determine the efficacy of the alpha-glucosidase inhibitor miglitol (BAYm 1099) regarding the starch content of food. RESEARCH DESIGN AND METHODS--Thirty-six non-insulin-dependent diabetes mellitus (NIDDM) subjects were studied in a double-blind randomized study comparing treatment with a single dosage of 100 mg miglitol or placebo and a single-blind crossover comparison of three test meals in which the carbohydrate contained either 30, 50, or 70% starch, and quantities of fat and protein were kept constant. RESULTS--Postprandial blood glucose excursions were reduced by approximately 50% with miglitol after all test meals. In contrast, after miglitol treatment, maximum postprandial serum C-peptide and insulin values reached the same levels as after placebo treatment, although the time to reach these maximum levels was delayed. Free fatty acid values decreased after both miglitol and placebo similarly. Twenty-eight untoward events in 15 patients were reported in the miglitol treatment group and 11 events in 7 patients in the placebo treatment group. CONCLUSIONS--Miglitol reduces postprandial blood glucose excursions independent of the starch content of the meal. Because no effects were found on incremental postprandial maximal levels of serum insulin and C-peptide, it may be that miglitol exerts, in addition to a delay of intestinal carbohydrate absorption, extraintestinal effects as well, particularly effects on disposition of glucose or anti-insulin counterregulatory factors.  相似文献   
40.

Background

Apolipoprotein (APOE) ?4 allele has been associated with cardiac dysfunction in Alzheimer's disease and β-thalassemia. We investigated the association between APOE genotypes and left ventricular dysfunction in a population of community-dwelling elderly subjects.

Methods

This study was performed in the Rotterdam Study, a population-based prospective cohort study among elderly subjects. For 2206 participants, a baseline echocardiogram and blood specimens for APOE typing were available. Cardiac dysfunction was considered present when fractional shortening was ≤25%. Multivariate logistic regression was used to calculate odds ratios (ORs). The ?3/?3 genotype served as a reference category.

Results

In participants who were homozygous for the ?4 allele, the odds of cardiac dysfunction was increased 3-fold (OR, 3.1; 95% CI, 1.2-8.1), whereas the odds of cardiac dysfunction in persons with APOE ?3/?4 was not significantly increased (OR, 1.5; 95% CI, 0.9-2.5). There was a significant allele-effect relationship for the ?4 allele (P-trend <.05). These elevated odds remained after adjustment for cholesterol levels and atherosclerosis parameters. Risks associated with APOE ?4/?4 and APOE ?3/?4 were more pronounced in participants aged ≥65 years.

Conclusion

The APOE ?4 allele is an independent risk factor for cardiac dysfunction in elderly people. Besides well-known effects on atherosclerosis and cholesterol levels, there may be other mechanisms, such as apoptosis, through which this allele exerts negative effects on myocardial performance.  相似文献   
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