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51.
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53.
Celińska-Cedro D Teisseyre M Woynarowski M Socha P Socha J Ryzko J 《Journal of pediatric surgery》2003,38(7):1008-1011
Background/purpose
Endoscopic variceal ligation (EVL) is effective in controlling rebleeding from esophageal varices in children, but there is no data on the use of EVL to prevent initial bleeding. The objective of this study was to prospectively evaluate the efficacy of EVL in preventing the first hemorrhage from esophageal varices in children.Methods
Thirty-seven children with portal hypertension (22 liver cirrhosis, 15 portal vein thrombosis), aged 4 to 17 years (M = 9.5 ± 4.4 years) were included in the study. The criteria for inclusion were (1) no previous variceal bleeding; (2) the presence of esophageal varices classified grade II or more, and (3) their enlargement by at least I grade after 6 months of observation without endoscopic treatment or appearance of endoscopic signs of high bleeding risk. A Multi-Band Ligator was used, and 2 to 6 bands were fixed under general anesthesia during one procedure depending on the number and size of varices. Follow-up examinations were performed every 3 months, repeating the procedure if necessary. In total, 75 procedures of EVL were performed, from one to 5 in each patientResults
Four patients underwent liver transplantation before eradication of varices. Two others were excluded from the observation because of lack of compliance to the protocol. Of the remaining 31 patients, eradication of varices was achieved in 28 children (90.3%) after 2.0 EVL sessions performed at 3-month intervals. The average time of follow-up after cessation of treatment is 16 months. No bleeding from varices occurred in any child during or after treatment. There were no differences in results between children with liver cirrhosis and portal vein thrombosis. Development of hypertensive gastropathy was observed in 2 children with one episode of bleeding. Recurrence of varices without bleeding occurred in 3 children after 12, 13, and 28 months from eradication.Conclusions
The study results confirmed that endoscopic variceal ligation is a safe and highly effective procedure in children with portal hypertension, regardless of its etiology. Eradication of esophageal varices was followed by 16 months free of bleeding. Prolonged observation is mandatory to conclude if preventive EVL influences the natural history of disease and diminishes the risk of first bleeding onset. 相似文献54.
Stachowski J Barth C Michałkiewicz J Krynicki T Jarmoliński T Runowski D Lewandowska-Stachowiak M Zaniew M Warzywoda A Bortkiewicz E Dobosz M Maciejewski J Baldamus CA 《Pediatric nephrology (Berlin, Germany)》2000,14(8-9):779-785
T cells are involved in the pathogenesis of nephrotic syndrome (NS). The aim of the study was to determine whether the activity
of T-helper-1 (Th1) and T-helper-2 (Th2) cells and the distribution of the lymphocyte subsets, namely CD45RA+CD4+ (”naive”
helper T cells, suppressor-inducer), CD45RA+CD8+ (”naive” suppressor T cells, suppressor-effector), CD45RO+CD4+ (”memory”
helper T cells), are predictive for steroid sensitivity in children with primary NS. These parameters were assessed at the
onset of disease, before initiation of steroid therapy. Two groups of NS children were retrospectively formed according to
steroid sensitivity (SS) or resistance (SR). The activity of Th1 and Th2 cells was defined by the production of interleukin-2
(IL-2), interferon-γ, IL-4, and IL-10 in the supernatants of CD4+ T cell cultures activated with autologous monocytes presenting
tetanus toxoid (TT). Peripheral lymphocyte subsets were determined using double- or triple-color flow cytometry. In SS children
with NS we found a decreased proliferative response of CD4+ T cells to TT stimulation, cytokine synthesis indicating the predominance
of Th2 activity, and an increased percentage of activated suppressor-inducer (CD45RA+ CD4+CD25+, 5.18±0.8, P<0.001) and suppressor-effector (CD45RA+CD8+CD25+, 2.05±0.6, P<0.01) cells, with the concomitant reduction of activated memory cells (CD45RO+CD4+CD25+, 0.2±0.1, P<0.001). In children with SRNS we found an increased proliferative response of CD4+ T cells to TT, a rise in activated memory
(CD45RO+CD4+CD25+, 3.82±0.7, P<0.01) and suppressor-inducer peripheral T cells (CD45RA+ CD4+CD25+, 3.85±0.6, P<0.01), but a low percentage of activated suppressor-effector (CD45RA+CD8+ CD25+, 0.5±0.2, P<0.05) T cells. We conclude that prior to treatment the distribution of lymphocyte subpopulations in peripheral blood together
with Th1 and Th2 cell activity provides a useful tool for evaluating the likelihood of steroid sensitivity in patients with
primary NS.
Received: 3 November 1998 / Revised: 1 September 1999 / Accepted: 8 September 1999 相似文献
55.
Grizzle WE Semmes OJ Basler J Izbicka E Feng Z Kagan J Adam BL Troyer D Srivastava S Thornquist M Zhang Z Thompson IM 《Urologic oncology》2004,22(4):337-343
Prostate-specific antigen (PSA) screening has led to a dramatic increase in prostate cancer detection with a concurrent stage migration. Although the test has revolutionized prostate cancer detection by identifying disease that is potentially curable in the majority of men, only 25% of men receiving test results of PSA > 4 ng/ml will have prostate cancer and many men receiving a normal PSA will have disease, including high-grade disease. There is a need for improved biomarkers for detecting prostate cancer. One such method of cancer detection is surface-enhanced laser desorption and ionization (SELDI). The Early Detection Research Network (EDRN) validation study for SELDI for prostate cancer is described. In a three-stage study, the portability and reproducibility of the technique will be determined; the predictive algorithm will be refined in a multi-institutional case-control population; followed by ultimate validation in the context of a prospective trial with complete disease ascertainment. The unique aspect of the EDRN SELDI validation study is the novel use of two groups of cancer cases: those cases with higher-risk disease (Gleason > or = 7) and those cases with lower-risk disease (Gleason < or = 6). This study will allow the first evaluation of a predictive algorithm that includes prognosis in disease screening. The EDRN SELDI prostate cancer biomarker validation study is a rigorous evaluation of a new detection method for prostate cancer. The methodologies used for this evaluation will prove useful for guiding future biomarker studies in this challenging disease. 相似文献
56.
Elzbieta Kowalska Steven A Narod Tomasz Huzarski Stanislaw Zajaczek Jowita Huzarska Bohdan Gorski Jan Lubinski 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1302-1306
Women who are born with constitutional heterozygous mutations of the BRCA1 gene face greatly increased risks of breast and ovarian cancer. The product of the BRCA1 gene is involved in the repair of double-stranded DNA breaks and it is believed that increased susceptibility to DNA breakage contributes to the cancer phenotype. It is hoped therefore that preventive strategies designed to reduce chromosome damage will also reduce the rate of cancer in these women. To test for increased mutagenicity of cells from BRCA1 carriers, the frequency of chromosome breaks was measured in cultured blood lymphocytes following in vitro exposure to bleomycin in female BRCA1 carriers and was compared with noncarrier relatives. The frequency of chromosome breaks was also measured in BRCA1 carriers following oral selenium supplementation. Carriers of BRCA1 mutations showed significantly greater mean frequencies of induced chromosome breaks per cell than did healthy noncarrier relatives (0.58 versus 0.39; P < 10(-4)). The frequency of chromosome breaks was greatly reduced following 1 to 3 months of oral selenium supplementation (mean, 0.63 breaks per cell versus 0.40; P < 10(-10)). The mean level of chromosome breaks in carriers following supplementation was similar to that of the noncarrier controls (0.40 versus 0.39). Oral selenium is a good candidate for chemoprevention in women who carry a mutation in the BRCA1 gene. 相似文献
57.
58.
Influence of felbamate on the antinociceptive action of morphine, metamizol and indomethacin in mice
The influence of felbamate (200 mg/kg or 50 mg/kg) on antinociceptive effect of morphine (10 mg/kg), metamizol (500 mg/kg) and indomethacin (10 mg/kg or 1.4 mg/kg) was investigated in a mouse model using the hot-plate test. All drugs were injected intraperitoneally. Felbamate was administered to mice 30 min before applying the analgesic drugs. Measurement of nociception was performed within 2 h after felbamate administration. The research studies were further conducted with a multiple (10 days) drug dosage. Felbamate in the dose of 200 mg/kg significantly increases the analgesic effect of morphine and weakens the effect of metamizol and indomethacin. Multiple administration of felbamate does not affect the activity of morphine and metamizol, but decreases analgesic effect of indomethacin. 相似文献
59.
Wnuk SF Lewandowska E Sacasa PR Crain LN Zhang J Borchardt RT De Clercq E 《Journal of medicinal chemistry》2004,47(21):5251-5257
Sonogashira coupling of (E)-6'-iodohomovinyl nucleosides 1 with (trimethylsilyl)acetylene gave the conjugated 8'-(trimethylsilyl)enyne derivatives of the adenosine 2a and uridine 2b with expected E-stereochemistry. Desilylation of 2a,b with tetrabutylammonium fluoride followed by treatment with N-iodosuccinimide/AgNO(3) afforded 8'-iodoenynes 4a,b. Analogous coupling of (Z)-6'-iodohomovinyl nucleosides 7a,b produced (Z)-8'-(trimethylsilyl)enynes 8a,b, which were deprotected with aqueous trifluoroacetic acid to give the Z-enynes 9a,b. Stereoselective coupling of the adenosine 4'-acetylenic 11 and ethyl (Z)-3-bromoacrylate followed by deprotection gave the conjugated enyne system attached in the reverse orientation at C4' 13. Because of their diverse stereochemical attributes, deprotected enyne analogues 5a, 6a, 9a, and 13 derived from adenosine require a different vicinity for binding with S-adenosyl-l-homocysteine (AdoHcy) hydrolase and/or addition of enzyme-bound water across the conjugated enyne system. Enyne 5a and 8'-iodoenyne 6a produced time-dependent and concentration-dependent inhibition of AdoHcy hydrolase (K(i), 0.55 and 118.5 microM, respectively). No reduction in NAD(+) content of the enzyme and no iodide ion released were observed upon incubation of 6a with the enzyme, while incubation of 5a produced 30% reduction in the NAD(+) content of the enzyme. No specific antiviral activity was noted for 5a,b, 6a,b, 9a,b, and 13 against any of the viruses tested; the E-iodoenynes 6a and 6b inhibited HIV-1 virus (IC(50), 1.1 and 1.8 microM; selectivity index, 7 and 3, respectively). The E-enyne 5a showed activity against cytomegalovirus at a concentration (EC(50), 30 microM) that was 3- to 10-fold lower than the cytotoxic concentration. 相似文献
60.
Petriczko E Horodnicka-Józwa A Ostrowska I Szmit-Domagalska J Wójcik K Adamczyk T Walczak M 《Pediatric endocrinology, diabetes, and metabolism》2008,14(2):119-123
The authors would like to present the difficulties in differentiation of diabetes mellitus type 1 and type 2 in adolescence on the basis of two 17 years-old patients. In both patients' cases the following symptoms: polydipsia, polyuria and weight loss with hyperglycemia and glycosuria have been observed for a few months. During laboratory studies some additional abnormalities were observed: elevated HbA1c, dyslipidemia and high level of liver enzymes. Normal level of insulin as well as C-peptide lack of ketonuria and negative parameters of autoimmunologic reaction the supported diagnosis of diabetes mellitus type 2. Due to insulin therapy and metformin a correct level of glycemia was achieved. CONCLUSION: Decompensated diabetes mellitus type 2 in adolescents may be difficult to differentiate with type 1. 相似文献