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1.
BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary.  相似文献   
2.
A pilot study was conducted to assess previously unrecognized visuo-spatial disturbances in 45 Alzheimer's demented (AD) patients and 59 control persons all over the age of 65 years, living in the community. The results of the Clock Drawing Test (CDT) revealed high frequency (78%) of deficient performative visuo-spatial skills of mild and moderate demented AD patients. The severity of dementia was found to be a good predictor of the deficit in visuoconstructive performance. The most frequent drawing mistakes were the misplacement of numbers and clock hands, which may relate to dysfunctions of the right inferior parietal cortex. The right-left orientation (RLO) for the own body was not deteriorated in AD patients. However, significantly lower scores for RLO in the mental rotation subtest were found in mild and moderate AD groups. There were large inter-individual differences in the test scores of both demented groups. Thirty-one percent and 49% of the AD patients scored 0 points or within the normal range (more than 4 points), respectively, indicating a pseudofocal onset pattern of the dementia. The results of the CDT and Right-Left Orientation Test (RLOT) with Mental rotation showed significant positive correlation with other cognitive functions of Mini Mental State Exam, such as attention-calculation, recall and writing, and indicate that the visuo-spatial orientation (VSO) is a composite of different cognitive skills. The CDT and RLOT appears to be a useful tool for screening the elderly for disturbed VSO.  相似文献   
3.
Any clinical intervention (e.g., coronary angioplasty, thrombolysis) used to reintroduce blood flow to an ischemic region of the myocardium is accompanied by a complex enzymatic cascade of reactions resulting in severe injury to the heart, termed myocardial ischemia/reperfusion (I/R) injury. In this study, we evaluated the ability of H-3010 (1-hydroxy-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole-3-carboxylic acid (2-(3,4-dimethoxyphenyl)-5-([2-(3,4-dimethoxyphenyl)ethyl]-methylamino)-2-isopropylpentyl)-amide), a pyrroline modification of verapamil (2-(3,4-dimethoxyphenyl)-5-[2-(3,4-dimethoxyphenyl)ethylmethyl-amino]-2-(1-methylethyl)pentanenitrile), to protect the heart against I/R-mediated injury. Isolated perfused rat hearts pretreated with verapamil and H-3010 were subjected to 30 min of global no-flow ischemia followed by 45 min of reperfusion. The recovery (expressed as a percentage of preischemic baseline) in contractile function (left ventricular developed pressure) of hearts subjected to I/R was significantly higher in hearts treated with H-3010 at 5 microM (51.0 +/- 6.4%) as well as at 50 microM (75.1 +/- 7.4%) as compared with verapamil at 5 microM (32.2 +/- 3.7%) or untreated control hearts (18.1 +/- 2.8%). Creatine kinase release was significantly attenuated in hearts treated with H-3010 (45.7 +/- 4.5 U/liter) as compared with untreated controls (131.5 +/- 6.4 U/liter). Similar trends were also observed for lactate dehydrogenase release as well. A marked reduction in percent area of infarction was observed in the H-3010 group (11.7 +/- 1.6%) compared with verapamil (25.1 +/- 2.9%) and control (41.3 +/- 1.9%) groups. Additional in vitro studies showed a marked decrease in reactive oxygen species generation with H-3010. In conclusion, our data clearly demonstrated that the verapamil derivative, H-3010, significantly decreased I/R-induced cardiac dysfunction. This can be attributed to the combined benefits of the pyrroline moiety (antioxidant) and the parent verapamil component (antiarrhythmic) in the protection of the heart from I/R-induced injury.  相似文献   
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5.
ObjectiveNon-echo planar diffusion weighted magnetic resonance imaging is a reliable surveillance tool of residual cholesteatoma nowadays. It is not known whether the material of the ossicular chain prosthesis modifies the sensitivity and specificity of MRI in these cases. The aim of the study was to compare the sensitivity, specificity and a localization-specific accuracy of non-EPI DW MRI sequences for residual cholesteatoma in the following 3 subgroups: patients with titanium ossicular prosthesis (group T), with autologous cortical bone columella (group A) or without any reconstruction (group WR) of hearing bones.MethodsThis prospective study covered 28 cases with cholesteatoma of the middle ear undergone second-look surgery, who had preoperative PROPELLER DW-MRI. Surgical findings were compared to the results of the DWI-MRI.ResultsThe overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were: 0.76-0.8-0.76-0.8. Group T, group A and group WR sensitivity was 0.83-0.6-1, specificity: 0.75-0.75-0.85, PPV: 0.83-0.75-0.66, NPV: 0.75-0.6-1. Overall accuracy was 0.78. Size of missed cholesteatoma was 2-4 mm (mean: 2.66±1.15).ConclusionsVarious materials are suitable for ossicular chain reconstruction. The poor detectability of residual or recurrent cholesteatoma in the middle ears reconstructed with autologous bony prosthesis may still claim second-look surgery instead of the usage of non- EPI DWI sequences independently in these patients.  相似文献   
6.
The frequency of cerebrovascular injuries raises the importance of their immunohistological investigation in postmortem materials. Most injuries involve the impairment of the blood–brain barrier. The barrier is maintained by the glio‐vascular connections which break up following injuries. Some immunohistochemical alterations may refer to the impairment of the gliovascular connections. Laminin and the components of the dystroglycan complex show characteristic immunohistochemical alterations following various experimental injuries (stab wound, cryogenic lesion, arterial occlusions): immunoreactivity of β‐dystroglycan, α‐dystrobrevin and aquaporin 4 disappeared while that of utrophin and laminin appeared along the vessels, whereas α‐syntrophin visualized the reactive astrocytes but not the resting ones. The aims of the present study were to investigate whether these post‐lesion alterations: (i) are reproducible with immersive fixation, which is used in postmortem histology; (ii) are resistant to a postmortem delay before fixation; and (iii) are to be attributed to a direct effect of the lesion, or are mediated by processes occurring only in the living brain. Three models were investigated: (i) following lesions, some brains were fixed by transcardial perfusion, others by immersion; (ii) following lesions, the animals were decapitated and stored at room temperature for 8 or 16 h before fixation; and (iii) the lesions were performed after decapitation. Cryogenic lesions were performed by applying a dry ice cooled copper rod to the brain surface of ketamine‐xylazine anesthetized rats. The immunohistochemical reactions were performed on free‐floating sections cut with vibratome. Both immunoperoxidase and immunofluorescence methods were used. The fixation method – perfusive or immersive – did not change the post‐lesion phenomena investigated. The postmortem delay did not influence the β‐dystroglycan immunoreactivity, that is its lack delineated the area of the lesion. However, in the case of the other substances, various lengths of postmortem delay rendered the immunohistochemistry uninterpretable. The results suggest β‐dystroglycan immunostaining could be applied in the neuropathology to detect cerebrovascular impairments.  相似文献   
7.
Atherosclerotic plaques tend to involve arterial localizations in which blood flow is not laminar due to arterial bends and bifurcations. A 49-year-old man was admitted to hospital with breathlessness and was subsequently diagnosed with left ventricular failure. Coronary angiography revealed three-vessel coronary artery disease and an anomalous extra left anterior descending artery taking off from the right sinus of Valsalva and spared from atherosclerosis. The absence of side branches and the relative lack of bends in arterial geometry were considered to be the cause of resistance to atherosclerosis. The present case identifies local flow conditions as an important factor determining the genesis of atherosclerosis in arterial segments.  相似文献   
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9.
Authors trace an ochronotic Hungarian family, which moved from Slovakia to Hungary 300 years ago. As the family members lived in a relatively close village community the gene mutation had been survived silently for ages before the clinical symptoms developed. Family tree analysis could detect with the use of allele specific PCR amplification–the p.G161R mutation of the homogentisic acid 1,2-dioxygenase (HGD) gene, which resulted in a specific genotype appearing in the Slovak population. We found a heterozygote member of this family who has children with an alkaptonuria-homozygote and known–heterozygote genotypes so there would be a high risk of alkaptonuria in their offsprings. Therefore genetic counselling is highly recommended to minimize the risk factors.  相似文献   
10.
INTRODUCTION: Recent data suggest that the copper-containing semicarbazide-sensitive amine oxidase enzyme (SSAO) may play a role in vascular endothelial damage through conversion of certain endogenous monoamines, like methylamine into cytotoxic aldehydes, hydrogen peroxide and ammonia. SSAO is present in various human tissues and in the serum. Elevated SSAO activities have been reported in patients with both types of diabetes mellitus. The purpose of this study was to examine the possible association between serum SSAO activity and the different severity stages of diabetic retinopathy. PATIENTS AND METHODS: A prospective study was performed on a defined group of Type 2 diabetic patients (n = 93) compared to non-diabetic control subjects (n = 42). All participants underwent a detailed ocular examination (slit lamp, colour retinal photography, fluorescein angiography) and standard laboratory investigations. Age at diagnosis, duration of diabetes, presence of systemic hypertension, medication and BMI were recorded. Serum SSAO activity was determined by a radiometric procedure using [14C]-benzylamine as substrate. RESULTS: In the total group of Type 2 diabetic patients SSAO activity (mean +/- SD) was significantly elevated compared to non-diabetic controls (n = 93, 131.72 +/- 53.07 vs. n = 42, 89.56 +/- 26.89 pmol.mg-1 protein.hour-1, p < 0.0001). After dividing patients to four subgroups according to the severity of diabetic retinopathy, serum SSAO activity was significantly higher in patients with high-risk proliferative diabetic retinopathy (n = 16, 166.96 +/- 70.56 pmol.mg-1 protein.hour-1) compared to those without retinopathy (n = 42, 119.54 +/- 50.49 pmol.mg-1 protein.hour-1, p < 0.02). CONCLUSION: The results support the hypothesis that elevated SSAO activity may be involved in the pathogenesis of microvascular diabetic late complications, such as retinopathy. The pharmacological manipulation of SSAO activity might be an interesting new concept for prevention and treatment of diabetic retinopathy.  相似文献   
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