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91.
Alberto Feletti Elisabetta Marton Alessandro Fiorindi Pierluigi Longatti 《Acta neurochirurgica》2013,155(8):1467-1473
Background
Small soft ventricular tumors are good candidates for complete removal by a purely endoscopic technique. This approach is particularly interesting for lesions located in the posterior third ventricle and aqueductal lumen.Methods
We present our method of endoscospic aspiration through direct contact between the tumor and the working channel of a flexible scope.Results
Aspiration without the intermediate use of cannulas is safe and has proved to be effective in the apparently total or partial removal of three soft tumors of different pathologies located in the third ventricle or aqueductal lumen. In one case, a second neuroendoscopy a few months later to repeat endoscopic third ventriculostomy (ETV) offered a unique opportunity to observe the absence of the tumor and the restored anatomy.Conclusions
Neuroendoscopy provides a safe, effective way to radically resect small soft tumors in these troublesome locations and can be a valuable alternative to microsurgery. 相似文献92.
93.
Sandor Racz Eszter Hantosi Sandor Marton Krisztina Toth Diana Ruzsa Laszlo Halvax 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3712-3716
Objective: Maternal obesity affects one in every five women giving birth worldwide. This condition is associated with adverse perinatal outcomes, as well as increased morbidity and mortality for mother and offspring.Methods: We carried out a prospective study at the University of Pecs Medical Center, Pecs, Hungary, between 1 January 2013 and 1 January 2014. We enrolled 60 obese (body mass index >30?kg/m2) low-risk pregnant women and 108 age-, ethnicity-, and parity-matched nonobese pregnant control subjects. The ST segment of the fetal electrocardiogram was assessed by STAN® monitoring. Neonatal outcomes and cord gas analysis of the umbilical vessels were evaluated after birth.Results: No infant with definitive metabolic acidosis was delivered in either group. We observed 32 and 106 ST events in the obese and control group, respectively, but this difference was not statistically significant. To date, none of the infants delivered as part of this study have demonstrated developmental insufficiency.Conclusions: Obesity might not influence the fetal electrocardiogram during labor as an independent risk factor for adverse pregnancy outcomes. Studies with larger cohort sizes are needed to confirm our findings. 相似文献
94.
Leishmania donovani polyamine biosynthetic enzyme overproducers as tools to investigate the mode of action of cytotoxic polyamine analogs
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Roberts SC Jiang Y Gasteier J Frydman B Marton LJ Heby O Ullman B 《Antimicrobial agents and chemotherapy》2007,51(2):438-445
A number of anticancer and antiparasitic drugs are postulated to target the polyamine biosynthetic pathway and polyamine function, but the exact mode of action of these compounds is still being elucidated. To establish whether polyamine analogs specifically target enzymes of the polyamine pathway, a model was developed using strains of the protozoan parasite Leishmania donovani that overproduce each of the polyamine biosynthetic enzymes. Promastigotes overexpressing episomal constructs encoding ornithine decarboxylase (ODC), S-adenosylmethionine decarboxylase (ADOMETDC), or spermidine synthase (SPDSYN) revealed robust overproduction of the corresponding polyamine biosynthetic enzyme. Polyamine pools, however, were either unchanged or only marginally affected, implying that regulatory mechanisms must exist. The ODC, ADOMETDC, and SPDSYN overproducer strains exhibited a high level of resistance to difluoromethylornithine, 5'-{[(Z)-4-amino-2-butenyl]methylamino}-5'-deoxyadenosine, and n-butylamine, respectively, confirming previous observations that these agents specifically target polyamine enzymes. Conversely, augmented levels of polyamine biosynthetic enzymes did not affect the sensitivity of L. donovani promastigotes to pentamidine, berenil, and mitoguazone, drugs that were postulated to target the polyamine pathway, implying alternative and/or additional targets for these agents. The sensitivities of wild-type and overproducing parasites to a variety of polyamine analogs were also tested. The polyamine enzyme-overproducing lines offer a rapid cell-based screen for assessing whether synthetic polyamine analogs exert their mechanism of action predominantly on the polyamine biosynthetic pathway in L. donovani. Furthermore, the drug resistance engendered by the amplification of target genes and the overproduction of the encoded protein offers a general strategy for evaluating and developing therapeutic agents that target specific proteins in Leishmania. 相似文献
95.
Cytokine activation during attacks of the hyperimmunoglobulinemia D and periodic fever syndrome 总被引:9,自引:0,他引:9
Drenth JP; van Deuren M; van der Ven-Jongekrijg J; Schalkwijk CG; van der Meer JW 《Blood》1995,85(12):3586-3593
The hyperimmunoglobulinemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent febrile attacks with abdominal distress, joint involvement (arthralgias/arthritis), headache, skin lesions, and an elevated serum IgD level (> 100 U/mL). This familial disorder has been diagnosed in 59 patients, mainly from Europe. The pathogenesis of this febrile disorder is unknown, but attacks are joined by an acute-phase response. Because this response is considered to be mediated by cytokines, we measured the acute-phase proteins C-reactive protein (CRP) and soluble type-II phospholipase A2 (PLA2) together with circulating concentrations and ex vivo production of the proinflammatory cytokines interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF alpha) and the inhibitory compounds IL-1 receptor antagonist (IL-1ra), IL-10, and the soluble TNF receptors p55 (sTNFr p55) and p75 (sTNFr p75) in 22 patients with the hyper-IgD syndrome during attacks and remission. Serum CRP and PLA2 concentrations were elevated during attacks (mean, 213 mg/L and 1,452 ng/mL, respectively) and decreased between attacks. Plasma concentrations of IL-1 alpha, IL-1 beta, or IL-10 were not increased during attacks. TNF alpha concentrations were slightly, but significantly, higher with attacks (104 v 117 pg/mL). Circulating IL-6 values increased with attacks (19.7 v 147.9 pg/mL) and correlated with CRP and PLA2 values during the febrile attacks. The values of the antiinflammatory compounds IL-1ra, sTNFr p55, and sTNFr p75 were significantly higher with attacks than between attacks, and there was a significant positive correlation between each. The ex-vivo production of TNF alpha, IL-1 beta, and IL-1ra was significantly higher with attacks, suggesting that the monocytes/macrophages were already primed in vivo to produce increased amounts of these cytokines. These findings point to an activation of the cytokine network, and this suggests that these inflammatory mediators may contribute to the symptoms of the hyper-IgD syndrome. 相似文献
96.
Renner C; Ohnesorge S; Held G; Bauer S; Jung W; Pfitzenmeier JP; Pfreundschuh M 《Blood》1996,88(1):236-241
To investigate the mechanisms underlying the deficiency of T lymphocytes from patients with Hodgkin's disease, we investigated the expression of the T-cell receptor (TCR) zeta chain in patients with Hodgkin's disease. By flow cytometry using an anti-zeta chain monoclonal antibody, peripheral blood T lymphocytes from patients with untreated Hodgkin's disease were shown to express decreased levels of the TCR zeta chain. After stimulation by combined CD3 and CD28 cross- linking, T cells from Hodgkin's disease patients upregulated zeta chain protein expression to normal values within 48 hours and achieved a cytolytic potential and levels of interleukin (IL)-2 secretion that were not different from T cells obtained from healthy controls. These results show that downregulation of the TCR zeta chain in Hodgkin's T lymphocytes is a reversible event. Costimulation of CD3 and CD28 is a novel approach for overcoming the T-cell deficiency in Hodgkin's disease and might be exploited clinically. As upregulation of the zeta chain can also be achieved using bispecific monoclonal antibodies (BI- MoAbs) with specificity for tumor antigens and CD3 and CD28, respectively, an immunotherapy with CD3/CD30 and CD28/CD30 Bi-MoAbs may overcome and should therefore, not be jeopardized by the inherent T- cell deficiency in patients with Hodgkin's disease. 相似文献
97.
de Koning JP; Dong F; Smith L; Schelen AM; Barge RM; van der Plas DC; Hoefsloot LH; Lowenberg B; Touw IP 《Blood》1996,87(4):1335-1342
98.
Bishop JF; Matthews JP; Young GA; Szer J; Gillett A; Joshua D; Bradstock K; Enno A; Wolf MM; Fox R 《Blood》1996,87(5):1710-1717
High-dose cytarabine (ara-c) may overcome cytarabine resistance in leukemic blasts. It has been used as a successful salvage and in postremission therapy but not as initial induction treatment. Patients aged 15 to 60 years, presenting with newly diagnosed acute myeloid leukemia (AML) were randomized to receive either high-dose cytarabine, 3 g/m2 12 hourly on days 1, 3, 5, and 7 for 8 doses, daunorubicin 50 mg/m2 days 1 to 3, etoposide 75 mg/m2 days 1 to 7, (HIDAC-3-7) or standard dose cytarabine 100 mg/m2 continuous intravenous infusion for 7 days with daunorubicin and etoposide at the same dose and schedule as above (7-3-7). Patients could receive a second or third induction course if complete remission (CR) was not achieved. All patients received the same postinduction consolidation therapy (5-2-5) for 2 courses. Eligible patients had no prior chemotherapy or myelodysplastic disease. Patients have been followed for a median of 4.5 years. Of 301 patients treated, complete response (CR) was achieved in 71% with HIDAC- 3-7 and 74% with 7-3-7. For patients in CR, the estimated median remission duration was 45 months with HIDAC-3-7 and 12 months with 7-3- 7 (P = .0005 univariate analysis, P = .0004 multivariate analysis). The estimated percentage of patients relapse free 5 years after achieving a CR was 49% on HIDAC-3-7 and 24% on 7-3-7. Patients in CR tended to survive longer with HIDAC-3-7 but there were no overall survival differences between the two arms. HIDAC-3-7 was associated with significantly more toxicity in induction with more leukopenia, thrombocytopenia, nausea, and vomiting and eye toxicity (all P < .001) but a similar incidence of severe central nervous system and cerebellar toxicity compared to 7-3-7. The consolidation treatment was the same in both arms but caused significantly more leukopenia and thrombocytopenia in patients previously treated with HIDAC-3-7 induction (P < .0001). We conclude that a dose-effect exists for cytarabine in AML and that HIDAC- 3-7 prolongs remission duration and disease-free survival and is tolerable when used as initial induction therapy in patients with de novo AML. 相似文献
99.
Nosocomial infections in critically ill infectious disease patients: Results of a 7-year focal surveillance 总被引:2,自引:0,他引:2
Summary An incidence study on nosocomial infections in critically ill infectious disease patients was carried out in the intensive
care unit (ICU) of a university hospital for infectious diseases over a 7-year period (1 January 1990 to 31 December 1996).
A total 660 patients who stayed in the ICU for over 48 h were prospectively observed. The patients were divided into two groups:
one with central nervous system infections (442 patients) and the other with other severe infections (218 patients). The risk
of nosocomial sepsis and pneumonia was significantly higher in patients suffering from severe central nervous system infections.
The incidence of sepsis was 24.2% vs 11.4% (relative risk 1.95; 95% confidence interval 1.32–2.89); the incidence of pneumonia
was 30.5% vs 14.7% (relative risk 2.09; 95% confidence interval 1.47–2.96). The incidence of urinary tract infection was 14.3%
vs 13.3% (relative risk 1.07; 95% confidence interval 0.71–1.61). Density rates of nosocomial septic episodes were 21.1±37.1
vs 11.7±32.4 episodes/100 central venous-line days (P<0.006). Nosocomial pneumonia occurred only in mechanically ventilated
patients (36.9±61.2 vs 28.5±65.8 episodes per 1000 ventilatory days, P=0.012). Nosocomial urinary tract infection occurred
only in patients with urinary catheters (11.6±60.7 episodes/1000 urinary catheter days vs 18.7±90.1, P=0.886). Multivariate
regression analysis identified age, diagnosis of CNS infection, duration of urinary tract catheterization, the use of central
venous lines and mechanical ventilation as independent risk factors of nosocomial sepsis. Duration of mechanical ventilation,
use of steroids and diagnosis of CNS infection were independent risk factors of nosocomial pneumonia. A subanalysis identified
tetanus patients to be at particular risk of nosocomial infections. 相似文献
100.
High-dose intravenous gammaglobulin in alloimmunized platelet transfusion recipients 总被引:1,自引:1,他引:1
High-dose intravenous gammaglobulin (polyvalent immunoglobulin G) has been shown to be of benefit in some patients with immune thrombocytopenic purpura (ITP), possibly by producing reticuloendothelial system blockade. We studied this approach in patients refractory to random donor platelet transfusion using an IV IgG preparation manufactured by the Swiss Red Cross. Eleven adult patients with acute leukemia received either 0.4 g IgG/kg/d intravenously X five days (four patients) or 0.6 g/kg/d X five days (seven patients). All patients had high levels of lymphocytotoxic antibody and poor responses to random donor platelets. Except for mild headaches in two patients, there were no side effects related to the IgG infusions. All patients had significant elevations of serum IgG on the day after completion of treatment. Either random donor or partially HLA-matched platelet transfusions were administered the day after and, in some cases, during the IgG therapy. No patient had an improvement in one hour posttransfusion platelet count increments. Two additional patients received pooled platelet concentrates incubated for 30 minutes at 37 degrees C with IgG at a final concentration of 3 g% prior to transfusions. These results indicate that high-dose IgG, an extremely expensive treatment, cannot be recommended for alloimmunized adults with leukemia. 相似文献