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A method is described for the synthesis of isotopically labeled cortisone from commercially available cortisone acetate through a Delta(4,6)-dieneone. Direct deuteration of the dienone acetate with various catalysts in different solvent systems failed to give an isolable product. Initial hydrolysis of the side-chain ester of the Delta(4,6)-dieneone and subsequent derivatization gave the key intermediate, 17alpha,20;20,21-bismethylenedioxy-pregna-4,6-diene-3,11-dione, which could be satisfactorily deuterated to the desired product. The availability of [6,7-(2)H]cortisone will provide a tool for the future study of the metabolism of cortisone in human tissues.  相似文献   
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INTRODUCTION: Renal insufficiency is the most common etiology of secondary hyperparathyroidism. In case of resistance for conservative treatment, methods of choice are surgical intervention or percutaneous ethanol injections. AIM OF THE STUDY: The aim of the study was to evaluate usefulness of percutaneous ethanol injection therapy in the treatment of patients with secondary hyperparathyroidism. MATERIAL AND METHODS: We performed percutaneous 96% ethanol injections under USG guideance in 51 patients: 22 women (mean age 49.6 years) and 29 men (46.6 yrs). The base level of parathormone was 689.35 pg/ml. We managed to visualize one parathyroid gland in 34 patients, 2 in 12, 3 in 5 patients. The mean volume of a single gland was 0,8 cm3. All the injections were performed with the use of needle number 6. We repeated injections in case of no effects. One injection was performed in 18 patients, 2 in 18, 3 in 13, 5 in 1 and 6 in 1 patient. Before and after the treatment patients were examined with USG, scintigraphy and densitometry. Serum levels of calcium (Ca), phosphorus (P), parathormone (PTH) and alkaline phosphatase (FA) activity were also obtained. The main criteria for success was decrease in parathormone level of 50% or more in comparison with pre-injection level or to less than 200 pg/ml. RESULTS: In the whole group of patients after the first month, positive results were observed in 67%. There were no changes in 23%, and PTH level increased in 10%. After 6 months-positive results in 53%, no change in 35% and increase in 12%. We noted the best results in patients with PTH less than 800 pg/ml-72% of them had positive results after 1 as far as after the 6 month. CONCLUSIONS: Percutaneous ethanol injections are valuable method of treatment of secondary hyperparathyroidism. The best results can be obtained if PTH level is less than 800 pg/ml, one parathyroid gland dominating over the rest is visualised in USG, and if patient responds after 1 or at least 2 injections.  相似文献   
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A couple was referred for cytogenetic examination due to idiopathic miscarriages. The proband proved to be a carrier of chromosomal translocation and her partner's karyotype was found to be normal. The karyotype of the proband is 46,XX,t(4;22)(q23;q11.2) and can be regarded as a reason of fertility problems in the investigated couple. The risk of further miscarriages is high, but the risk of a progeny with abnormal karyotype is rather low, as the progeny would probably have lethal imbalances.  相似文献   
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Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous group of tumours with various clinical characteristics. These tumours generally exhibit complex karyotypes. Few studies of genomic imbalances have been performed exclusively in subgroups of larynx cancer samples at different stages of the disease. In the present study, chromosomal gains and losses were investigated in 52 larynx tumours, by using comparative genomic hybridization (CGH). The mean number of observed alterations was 37.7 per tumour. The most common sites of losses were 1p, 13q, Xp, and the most common gains were located in 1p, 9q, 16q. The overall number of gains was negatively associated with cancer grading. G1 tumours were also characterized by a higher frequency of deletions in 13q32 and amplifications in 1q23, than tumours in other grades (p < 0.05). The frequency of losses of 13q22 also positively associated with tumour size. There was no association between the frequency of losses in 13q and the presence of lymph node metastases at the time of diagnosis. Another statistically significant association was observed for gains at 1q22-23 and tumour size (p < 0.01). No statistically significant difference in the frequency of most common imbalances was detected between primary tumours with lymph node metastases and those without metastases. In conclusion, we discovered a significant involvement of 13q deletions in the progression of larynx cancer. All the other significant changes observed in the present study were reported previously as being important for HNSCC progression. It seems that multiple genes are disrupted in the process of neoplastic transformation in the larynx, and the networks of events remain to be elucidated.  相似文献   
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Microtubules (MTs) are polymers of alpha and beta tubulin dimers that mediate many cellular functions, including the establishment and maintenance of cell shape. The dynamic properties of MTs may be influenced by tubulin isotype, posttranslational modifications of tubulin, and interaction with microtubule-associated proteins (MAPs). End-binding (EB) family proteins affect MT dynamics by stabilizing MTs, and are the only MAPs reported that bind MTs via a calponin-homology (CH) domain (J Biol Chem 278 (2003) 49721-49731; J Cell Biol 149 (2000) 761-766). Here, we describe a novel 27 kDa protein identified from an inner ear organ of Corti library. Structural homology modeling demonstrates a CH domain in this protein similar to EB proteins. Northern and Western blottings confirmed expression of this gene in other tissues, including brain, lung, and testis. In the organ of Corti, this protein localized throughout distinctively large and well-ordered MT bundles that support the elongated body of mechanically stiff pillar cells of the auditory sensory epithelium. When ectopically expressed in Cos-7 cells, this protein localized along cytoplasmic MTs, promoted MT bundling, and efficiently stabilized MTs against depolymerization in response to high concentration of nocodazole and cold temperature. We propose that this protein, designated CLAMP, is a novel MAP and represents a new member of the CH domain protein family.  相似文献   
208.
The title compounds, (cinchonidinium)trichlorocobalt(II) [(C(19)H(23)ON(2))CoCl(3)] (CoCdn) and (quinidinium)trichlorocobalt(II) [(C(20)H(25)O(2)N(2))CoCl(3)] (CoQd), are zwitterions that differ in absolute configuration and conformation. In both complexes, the sp(3) nitrogen of quinuclidine is protonated, whereas the sp(2) nitrogen of quinoline is linked to the Co(II) atom, which coordinates three chlorine atoms in distorted tetrahedral geometry. The mutual orientations of the quinoline and quinuclidine moieties in CoCdn and CoQd differ significantly because of different hydrogen bonding involving the hydroxyl group. In both complexes, the quinuclidine NH groups and hydroxyl groups are hydrogen-bond donors to the chlorine atoms of Co(II) tetrahedra. In CoQd the hydrogen bonding leads to formation of a nine-membered ring consisting of Co, two chlorines, and a fragment of the quinidine molecule. A comparison of the crystal structures of four Cinchona alkaloid complexes with trichlorocobalt(II) shows that their space groups are determined by the absolute configuration of the alkaloid, whereas the hydrogen-bonding pattern is mainly affected by the substituent in the quinoline ring, i.e., by hydrogen or methoxyl group.  相似文献   
209.
Dermatitis herpetiformis (DH) is a subepidermal autoimmune disease characterized by skin and intestinal lesions consistent with coeliac disease. There are also some data that metalloproteinases (MMPs) are involved in the development of skin lesions in DH, however their exact role in this process is not fully understood. The aim of the study was to investigate whether MMPs and their inhibitors are involved in pathogenesis of DH. Skin biopsies were taken from 13 patients with active DH and from 10 healthy subjects. The localization and expression of MMPs and TIMPs were examined by immunohistochemistry. MMPs expression was detected in basal keratinocytes and in the whole epidermis in all of the DH subjects. Neutrophils in microabscesses and in blister fluid were also positive for MMPs. Expression of TIMPs was moderate or weak in all examined biopsies. Our results allow us to conclude that imbalance between these enzymes takes an important role in the pathogenesis of DH.  相似文献   
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The O-polysaccharide (O-antigen) of Providencia stuartii O44:H4 (strain 3768/51) was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, and H-detected (1)H,(13)C HSQC, and HMQC-TOCSY experiments. The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure: [Formula: see text].  相似文献   
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