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1.
We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes.  相似文献   
2.
Dantrolene seems to be the causal therapy in malignant hyperthermia (MH) crisis but the complex mechanisms of MH and dantrolene therapy are still not fully understood. The influence of dantrolene on ryanodine-induced contractures has been reported in animal studies only. In the present study 20 patients from] 7 families were tested for MH using the protocol of the European Malignant Hyperthermia Group. In addition ryanodine-induced contractures were evaluated following bolus application of 10.0 μmol · 1-1 ryanodine. After pretreatment with 1 μimol · 1-1 dantrolene ryanodine-provoked contractures developed significantly later in MHS (15.8±1.8 min) and MHN (46.0±4.2 min) muscle specimens than after ryanodine alone (MHS 4.8±0.7 min), (MHN 13.7±0.9 min). They were no longer observed in either group after pretreatment with 5 μimol · 1-1 dantrolene. We conclude that dantrolene is able to attenuate ryanodine-induced contractures dose-dependendy, and therefore it is speculated that dantrolene could specifically act at the ryanodine receptor binding site.  相似文献   
3.
PURPOSE: The low incidence of mortality and major morbidity in anesthesia makes it difficult to study the pattern of potential accidents and to develop preventive strategies. Anesthetic 'near-misses', however, occur more frequently. Using data from a simple routine-based system of problem reporting, we have analyzed the pattern and causes of serious non-fatal problems, in order to improve preventive strategies. METHODS: We prospectively recorded anesthesia-related information from all anesthetics for five years. The data included intraoperative problems, which were graded into four levels, according to severity. We analyzed only the serious nonfatal problems, which were sorted according to clinical presentation, and also according to which factor was most important in the development of the problem. We assessed any untoward consequences for the patient, and whether the problems could have been prevented. RESULTS: Serious problems were recorded in 315 cases out of 83,844 (0.4%). Anesthesia was considered the major contributing factor in 111 cases. Difficult intubation, difficult emergence from general anesthesia, allergic reactions, arrhythmia and hypotension were the dominating problems. Twenty-six anesthesia related problems resulted in changes in level of postoperative care, and one patient later died in the intensive care unit after anaphylactic shock. Eighty-two problems could have been prevented by simple strategies. CONCLUSION: Analysis of serious nonfatal problems during anesthesia may contribute to improved preventive strategies. Data from a routine-based system are suitable for this type of analysis. Intubation, emergence, arrhythmia, hypotension and anaphylaxis cause most serious problems, and should be the object of preventive strategies.  相似文献   
4.
Local recurrence of bilateral breast carcinomas is rare, but of biological interest, since it is unclear as to which tumor the local recurrence is related to, the ipsilateral or the contralateral, or whether it is an independent neoplasm. The aim of this study was to investigate the genetic relationship of bilateral breast carcinomas to each other and to their local recurrences. Eight cases of bilateral breast carcinomas, five with and three without local recurrence were analyzed using a microsatellite assay for 13 microsatellite loci. The presence of loss of heterozygosity and microsatellite instability in the various tumors was used for clonal analysis. All eight bilateral breast carcinomas showed divergent alterations in at least two microsatellite loci, which ruled out a genetic relationship. Four of five local recurrences were genetically related to the ipsilateral tumor and unrelated to the contralateral tumor. Only one local recurrence that occurred 11.8 years after the surgery of an infiltrative lobular carcinoma simultaneously with distant metastases was genetically related to the contralateral breast carcinoma. Although the number of cases in our study is limited, there is evidence that local recurrence of bilateral breast carcinoma frequently arises from the ipsilateral tumor.  相似文献   
5.
Summary The role of lysophosphatidylcholine and arachidonic acid in signal transduction was investigated using subcellular organelles and permeabilized cells from liver. Both substances can be generated intracellularly by the action of phospholipase A2 on phosphatidy1choline. Lysophosphatidylcholine as well as arachidonic acid raised the free Ca2+ concentration in the incubation media of permeabilized cells, isolated mitochondria and microsomes. The half maximally effective concentrations for Ca2+ release from mitochondria were 78 ± 1 mol/l for lysophosphatidylcholine and 80 ± 11 mol/l for arachidonic acid. Though isolated microsomes released Ca2+ in response to both agents, the combined presence of mitochondria and microsomes did not exhibit a synergism in Ca2+ release in response to arachidonic acid; the increase in the free Ca2+ concentration in response to lysophosphatidylcholine was even smaller than with mitochondria alone. It is concluded that the two reaction products of phospholipase A2 can raise the cytoplasmic Ca2+ concentration and therefore may participate in cellular signal transduction. Send offprint requests to I. Rustenbeck at the above address  相似文献   
6.
Local recurrence is a serious complication of breast carcinoma that reduces quality of life and influences prognosis. The aim of this study was to determine whether local recurrences of breast carcinoma are genetically related to the primary tumours. Forty cases of locally recurrent breast carcinomas (median onset: 3.6 years after primary surgery) were analysed: 22 patients had undergone breast-conserving therapy and 18 mastectomy. Eighteen microsatellites on chromosomes 2p, 3p, 5q, 10q, 11p, 11q, 13q, 17q, 17p, 18p were amplified by PCR using fluorescent-labelled primers, automatically detected after polyacrylamide gel electrophoresis and analysed for loss of heterozygosity (LOH) or microsatellite instability (MSI). Follow-up data were available for 39 cases with a median value of 89 months. All LOH and MSI found in the primary tumours were also present in the corresponding recurrences, indicating that they are genetically related to the primary tumours and not secondary malignancies in the same breast. MSI was found in three cases, of which one harboured MSI at more than two loci. The median value of LOH per case was significantly higher in the recurrent (four per case) compared to the primary tumours (two per case; p < 0.001, Mann-Whitney test), reflecting the genotype of tumour progression. Early local recurrence was associated with specific LOH for TP53.15 (p = 0.018, log-rank test) in the primary tumours. LOH on D13S1699 or D17S855 was associated with lymph node metastases (p = 0.024 and p = 0.019, respectively; chi-square test). In addition, tumour grade, lack of oestrogen or progesterone receptor expression, young patient age and early appearance of local recurrence significantly correlated with poor survival. The development of local recurrence despite clear resection margins may result from residual DCIS distant from the invasive carcinoma, homing of circulating tumour cells, or genetically altered, histologically normal breast tissue not immediately adjacent to the invasive carcinoma.  相似文献   
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8.
To more closely define the risk of infection by the agent of Lyme disease in Europe, we determined whether spirochetal prevalence increases throughout the development of theIxodes ricinus vector tick. Of all ticks that could be flagged from vegetation,I. ricinus were by far the most abundant. Spirochetal infection rates in the adult stage of this tick (15%) are no higher than those in nymphs (18%) but greatly exceed those in larvae (0.7%). This tick therefore appears to attain infection mainly from the host of its larval stage, generally feeds on hosts that are noncompetent as reservoirs in its nymphal stage, and rarely inherits infection. Risk of human infection mainly derives from contact with the nymphal stage of the vector tick because the larva is rarely infected and the adult is large enough to be noticed and promptly removed.This work was supported in part by grant AI 19693 from the National Institute of Allergy and Infectious Disease and by grants from the city of Berlin  相似文献   
9.
ObjectiveTo estimate the impact of reduced consumption of free sugars in line with World Health Organization recommendations, on sugar farmers globally.MethodsUsing multiregion input–output analysis, we estimated the proportional impact on production volumes of a 1% reduction in free sugars consumption by the public. We extracted data on sugar production from the Food and Agriculture Organization of the United Nations database for the top 15 sugar-cane- and beet-producing countries globally, and created a custom multiregion input–output database to assess the proportions of production going to human consumption, drawing on household expenditure surveys and national input–output databases (data valid for years 2000–2015). We also considered the impact on production volumes in relation to countries’ gross domestic product.FindingsA high proportion of current sugar production from these countries goes to human consumption, and would thus be impacted by reduced consumption of sugars. The largest impacts on cane sugar production, and thus on farmers, would likely occur in Brazil, China, India and Thailand and on beet production in Belarus, Germany, Russian Federation and United States of America.ConclusionA global opportunity exists for public health leadership to bring together the health, economic, environmental and agriculture sectors to collaborate and build capacity for promotion of alternative livelihoods for sugar farmers. Lessons regarding strategy and the importance of political economy factors can be learnt from tobacco control measures. Further research to quantify the impact of reductions in sugars consumption would provide useful insights for designing policies to complement and strengthen efforts to improve diets and health.  相似文献   
10.
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