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11.
Several lines of evidence indicate that sialosyl Le a , tumor-associated carbohydrate antigen present on human colon carcinoma cells, is involved in formation of metastases. To study the role of this carbohydrate structure in development of metastases, we have used the clone of human colon carcinoma CX-1 cells transfected with antisense expression vector containing fragment of cDNA for a1,3/4-fucosyltransferase (FT III), which is involved in synthesis of sialosyl Le a tetrasaccharide. It has been reported previously that, in contrast to the parental cells, the antisense-transfected CX-1.1AS5 cells do not express sialosyl Le a and do not adhere to E-selectin-expressing CHO cells. In the present work we have studied the formation of liver metastases by CX-1.1AS5 cells after their orthotopic or intrasplenic implantation into athymic nu/nu mice. After orthotopic implantation of sialosyl Le a -negative colon carcinoma CX-1.1AS5 cells, the number of mice with liver metas-tases was markedly lower (21% of mice) in comparison with their number after implantation of the parental CX-1.1 cells (86% of mice). However, no differences in ability to form colonies in liver were observed between parental CX-1.1 cells and antisense-transfected CX-1.1AS5 cells after intrasplenic inoculation. The liver metastases were formed in 89% and 84% of mice, respectively. Our data support the thesis on the importance of sialosyl Le a antigen expression in the development of liver metastases by colon cancer cells, and indicate the role of transplantation route and primary tumor localization in formation of metastases.© Kluwer Academic Publishers 1998  相似文献   
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13.
Because tissues from all three germ layers contribute to the pharyngeal arches, it is not surprising that all major signaling pathways are involved in their development. We focus on the role of retinoic acid (RA) signaling because it has been recognized for quite some time that alterations in this pathway lead to craniofacial malformations. Several studies exist that describe phenotypes observed upon RA perturbations in pharyngeal arch development; however, these studies did not address whether RA plays multiple roles at distinct time points during development. Here, we report the resulting phenotypes in the hindbrain, the neural crest-derived tissues, and the pharyngeal endoderm when RA synthesis is disrupted during zebrafish gastrulation and pharyngeal arch morphogenesis. Our results demonstrate that RA is required for the post-gastrulation morphogenesis and segmentation of endodermal pouches, and that loss of RA does not affect the length of the pharyngeal ectoderm or medial endoderm along the anterior-posterior axis. We also provide evidence that RA is not required for the specification of pharyngeal pouch endoderm and that the pharyngeal endoderm consists of at least two different cell populations, of which the pouch endoderm is sensitive to RA and the more medial pharyngeal endoderm is not. These results demonstrate that the developmental processes underlying pharyngeal arch defects differ depending on when RA signaling is disturbed during development.  相似文献   
14.
Male Wistar rats were subjected to streptozotocin administration (85 mg/kg i.p.) and to cerebral air embolia with common carotids ligation. Electron microscope studies showed dark neurons, degeneration of endothelial cells and changes in basement membrane of brain capillaries, and changed astroglia in diabetic rats. Our results seem to support our previous findings in light microscopy and correspond with some others authors' suggestions that diabetes leads to chronic, generalized pathologic process in diabetic-rat brain, not-only dependent on vascular pathology, but which may be related to an oxidative/metabolic stress leading to a death of neurons in necrotic or apoptotic way.  相似文献   
15.
During the course of 1998, the Army Dental Care System launched "Put More 'Bite' into Health Promotion," a campaign to revitalize health promotion in the Army Dental Care System. In this paper, we discuss the content, rationale, and evidence base for three of five health promotion initiatives that are part of the campaign: mouthguard fabrication and counseling, sealant placement and education, and nursing caries education.  相似文献   
16.
Phenolic lipids were isolated from rye grains, cashew nutshell liquid (CNSL) from Anacardium occidentale, and fruit bodies of Merrulius tremellosus, and their effects on the electric eel acetylcholinesterase activity and conformation were studied. The observed effect distinctly depended on the chemical structure of the phenolic lipids that were available for interaction with the enzyme. All of the tested compounds reduced the activity of acetylcholinesterase. The degree of inhibition varied, showing a correlation with changes in the conformation of the enzyme tested by the intrinsic fluorescence of the Trp residues of the protein.  相似文献   
17.
Splenectomy is considered standard surgical therapy in hereditary spherocytosis. The procedure is indicated in patients with severe anemia, recurrent hemolytic, and aplastic crises. The aim of the study was to assess treatment outcomes in patients with hereditary spherocytosis who underwent total or partial laparoscopic splenectomy. Fifteen patients aged 4–17 yr underwent laparoscopic splenectomy from 2009 to 2012. Partial and total splenectomies were performed (five and 10 children, respectively). Hematologic parameters, liver function tests, and splenic volume before and after the surgery were analyzed retrospectively. Total follow‐up was 1–30 months. Hospitalization and operating time were similar in both groups. In partial splenectomy group, branches of splenic arteries gave better blood supply than short gastric vessels. In both groups, hematologic parameters were improved. Postoperative markedly elevated platelet count was maintained up to 6 months, and after that, platelet count gradually decreased to normal values. Bilirubin level was decreased in early postoperative period; however, it increased later to achieve levels lower than in preoperative period. No severe general infections were observed in both groups. Laboratory parameters (hemoglobin and bilirubin concentrations and RBC) after the surgery improved in all patients, and the effect was maintained during 12 months of follow‐up. Platelet count increased significantly after the surgery and was maintained at high levels during the next 6 months. However, it returned to preoperative levels within a year after the surgery. Our study showed that partial splenectomy was not inferior to total splenectomy. However, full assessment requires longer follow‐up and larger group of patients.  相似文献   
18.
A case of a 19-year-old woman suffering for 5 years from pharmacologically resistant hypertension, is presented. During invasive diagnostic procedures left renal artery aneurysm was found. Surgical resection with vessel prosthesis implantation was successfully performed. Examination carried-out 6 months later revealed good response to pharmacological treatment with normal levels of blood pressure.  相似文献   
19.
Somatic mosaicism for DNA copy‐number alterations (SMC‐CNAs) is defined as gain or loss of chromosomal segments in somatic cells within a single organism. As cells harboring SMC‐CNAs can undergo clonal expansion, it has been proposed that SMC‐CNAs may contribute to the predisposition of these cells to genetic disease including cancer. Herein, the gross genomic alterations (>500 kbp) were characterized in uninvolved mammary glandular tissue from 59 breast cancer patients and matched samples of primary tumors and lymph node metastases. Array‐based comparative genomic hybridization showed 10% (6/59) of patients harbored one to 359 large SMC‐CNAs (mean: 1,328 kbp; median: 961 kbp) in a substantial portion of glandular tissue cells, distal from the primary tumor site. SMC‐CNAs were partially recurrent in tumors, albeit with considerable contribution of stochastic SMC‐CNAs indicating genomic destabilization. Targeted resequencing of 301 known predisposition and somatic driver loci revealed mutations and rare variants in genes related to maintenance of genomic integrity: BRCA1 (p.Gln1756Profs*74, p.Arg504Cys), BRCA2 (p.Asn3124Ile), NCOR1 (p.Pro1570Glnfs*45), PALB2 (p.Ser500Pro), and TP53 (p.Arg306*). Co‐occurrence of gross SMC‐CNAs along with point mutations or rare variants in genes responsible for safeguarding genomic integrity highlights the temporal and spatial neoplastic potential of uninvolved glandular tissue in breast cancer patients.  相似文献   
20.
The objective of the paper was compare the effects and tolerability of combined therapy of multiple intravenous infusions of anti-tumour necrosis factor-alfa (TNF-alfa) monoclonal antibody (Remicade) with methotrexate versus treatment with sodium aurothiomalate and intramuscular depot methylprednisolone in rheumatoid arthritis (RA). We investigate also the interval necessary to obtain the improvement in both treatment groups. 36 patients commencing intramuscular sodium aurothiomalate therapy with intramuscular depot methylprednisolone acetate at weeks 0, 4, 8 and 12 in addition to chrysotherapy were compared in retrospective analysis with 32 patients starting with multiple intravenous infusions of infliximab, anti-TNF-alfa monoclonal antibody (Remicade) and methotrexate at a stable dose. Patients were assessed by composite clinical score (DAS 28) and C-reactive protein during 22 weeks of therapy. At week 2 and 6 a significantly greater percentage of infliximab-treated than gold-treated RA patients achieved improvement in each clinical measurement of disease activity. At 22 week of treatment moderate and good response according to EULAR criteria was achieved in 91% of infliximab-treated patients and 58% gold treated patients (p < 0.001). Adverse events were more frequently observed in infliximab-treated patients, but only gold-treated patients discontinued treatment because adverse events (2 patients due to proteinuria, 2 patients due to mucocutaneous changes and one patient due to leucopenia). The higher percentage of adverse events in infliximab-treated patients was caused mainly by the occurrence of infusion reactions (23 reactions out of 160 infusions); most of them were mild (somnolentia and headache) and transient. Viral infections (including herpes simplex and zoster) were more common in patients treated with infliximab and methotrexate. Combination therapy of infliximab and methotrexate is more effective in reducing clinical and biochemical disease activity than gold with methylprednisolone treatment in RA patients during 22 weeks of treatment, especially in the first 6 weeks.  相似文献   
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