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101.
RA Larson RK Dodge CA Linker RM Stone BL Powell EJ Lee P Schulman FR Davey SR Frankel CD Bloomfield SL George CA Schiffer 《Canadian Metallurgical Quarterly》1998,92(5):1556-1564
Recombinant human granulocyte colony-stimulating factor (G-CSF; filgrastim) shortens the time to neutrophil recovery after intensive chemotherapy, but its role in the treatment of adults with acute lymphoblastic leukemia (ALL) is uncertain. We randomly assigned 198 adults with untreated ALL (median age, 35 years; range, 16 to 83) to receive either placebo or G-CSF (5 microgram/kg/d) subcutaneously, beginning 4 days after starting intensive remission induction chemotherapy and continuing until the neutrophil count was >/=1, 000/microL for 2 days. The study assignment was unblinded as individual patients achieved a complete remission (CR). Patients initially assigned to G-CSF then continued to receive G-CSF through 2 monthly courses of consolidation therapy. Patients assigned to placebo received no further study drug. The median time to recover neutrophils >/=1,000/microL during the remission induction course was 16 days (interquartile range [IQR], 15 to 18 days) for the patients assigned to receive G-CSF and 22 days (IQR, 19 to 29 days) for the patients assigned to placebo (P < .001). Patients in the G-CSF group had significantly shorter durations of neutropenia (<1, 000/microL) and thrombocytopenia (<50,000/microL) and fewer days in the hospital (median, 22 days v 28 days; P = .02) compared with patients receiving placebo. The patients assigned to receive G-CSF had a higher CR rate and fewer deaths during remission induction than did those receiving placebo (P = .04 by the chi-square test for trend). During Courses IIA and IIB of consolidation treatment, patients in the G-CSF group had significantly more rapid recovery of neutrophils >/=1,000/microL than did the control group by approximately 6 to 9 days. However, the patients in the G-CSF group did not complete the planned first 3 months of chemotherapy any more rapidly than did the patients in the placebo group. Overall toxicity was not lessened by the use of G-CSF. After a median follow-up of 4. 7 years, there were no significant differences in either the disease-free survival (P = .53) or the overall survival (P = .25) for the patients assigned to G-CSF (medians, 2.3 years and 2.4 years, respectively) compared with those assigned to placebo (medians, 1.7 and 1.8 years, respectively). Adults who received intensive chemotherapy for ALL benefited from G-CSF treatment, but its use did not markedly affect the ultimate outcome. 相似文献
102.
103.
F Ribeiro-Dias M Russo FR Nascimento JA Barbuto J Timenetsky S Jancar 《Canadian Metallurgical Quarterly》1998,31(11):1425-1428
We describe a collective episode of psychogenic illness in an indigenous group (Embera) of Colombia, geographically isolated from its native homeland and surrounded by non-indigenous settlers. The condition, which affected three young adult men and six adolescent women, was attributed by them to a spell (maleficio). It was designated as ataques de locura (madness attacks) according to their traditional medical system; and as a conversive disorder with dissociative features by psychiatrists. Different therapeutic approaches, including antipsychotic medication, religious healers and traditional herbal remedies were unsuccessful. Contact with shamans of the same ethnic origin, on the other hand, proved to be an effective way of dealing with the symptoms. We interpret the situation as an expression of psychosocial stress secondary to cultural change. This medical problem bears close resemblance to other specific culture-bound syndromes such as ataques de nervios or possession syndromes and gives clues to ways of dealing with psychogenic expressions of cultural stress. 相似文献
104.
M Navarro J Chowen M Rocío A Carrera I del Arco MA Villanúa Y Martin AJ Roberts GF Koob FR de Fonseca 《Canadian Metallurgical Quarterly》1998,9(15):3397-3402
Recent reports have provided evidence of a link between the endogenous brain cannabinoid system and the endogenous central opioid systems. Here we report that the selective CB1 receptor antagonist SR 141716A induced behavioral and endocrine alterations associated with opiate withdrawal in morphine-dependent animals in a dose-dependent manner and that naloxone induced an opiate withdrawal syndrome in animals made cannabinoid-dependent by repeated administration of the potent cannabinoid agonist HU-210. Additionally CB1 and mu-opioid receptor mRNAs were co-localized in brain areas relevant for opiate withdrawal such as the nucleus accumbens, septum, dorsal striatum, the central amygdaloid nucleus and the habenular complex. These results suggest that CB1 cannabinoid receptors may play a role in the neuroadaptive processes associated with opiate dependence, and they lend further support for the hypothesis of a potential role of cannabinoid receptors in the neurobiological changes that culminate in drug addiction. 相似文献
105.
It has been shown that reactive oxygen species produced during the early phase of myocardial post-ischemic reperfusion are one of the main causes of reperfusion injury. This observation has led to various antioxidant strategies using many reactive oxygen species scavengers, including manganese complexes. The aim of the present work was to provide a reference study of the effects of manganese itself (MnCl2) on isolated rat hearts submitted to global total normothermic ischemia (30 min) and reperfusion (60 min). McCl2 was administered either during the first 10 min reperfusion (10(-5)M and 10(-4)M) or throughout reperfusion (10(-4)M). After 10 min reperfusion, no functional difference was evidenced between control and manganese-treated groups, whereas high energy phosphate contents were significantly higher in treated groups. MnCl2 10(-4)M enhanced the recovery of developed pressure between 40 and 55 min reperfusion. At the end of reperfusion, hearts treated during the first 10 min reperfusion showed a better metabolic recovery. The group treated throughout reperfusion showed a better metabolic recovery, but a reduced coronary flow and a weak recovery of developed pressure. These results suggest that MnCl2, administered during the early phase of reperfusion, protects against myocardial reperfusion injury. This effect might be mediated by manganese antioxidant properties. 相似文献
106.
Listeria monocytogenes is an intracellular bacterial pathogen that elicits a strong cellular immune response following infection and therefore has potential use as a vaccine vector. However, while infections by L. monocytogenes are fairly rare and can readily be controlled by a number of antibiotics, the organism can nevertheless cause meningitis and death, particularly in immunocompromised or pregnant patients. We therefore have endeavored to isolate a highly attenuated strain of this organism for use as a vaccine vector. D-Alanine is required for the synthesis of the mucopeptide component of the cell walls of virtually all bacteria and is found almost exclusively in the microbial world. We have found in L. monocytogenes two genes that control the synthesis of this compound, an alanine racemase gene (dal) and a D-amino acid aminotransferase gene (dat). By inactivating both genes, we produced an organism that could be grown in the laboratory when supplemented with D-alanine but was unable to grow outside the laboratory, particularly in the cytoplasm of eukaryotic host cells, the natural habitat of this organism during infection. In mice, the double-mutant strain was completely attenuated. Nevertheless, it showed the ability, particularly under conditions of transient suppression of the mutant phenotype, to induce cytotoxic T-lymphocyte responses and to generate protective immunity against lethal challenge by wild-type L. monocytogenes equivalent to that induced by the wild-type organism. 相似文献
107.
CA Geuijen RJ Willems P Hoogerhout WC Puijk RH Meloen FR Mooi 《Canadian Metallurgical Quarterly》1998,66(5):2256-2263
Bordetella pertussis fimbriae bind to sulfated sugars such as heparin through the major subunit Fim2. The Fim2 subunit contains two regions, designated H1 and H2, which show sequence similarity with heparin binding regions of fibronectin, and the role of these regions in heparin binding was investigated with maltose binding protein (MBP)-Fim2 fusion proteins. Deletion derivatives of MBP-Fim2 showed that both regions are important for binding to heparin. The role of H2 in heparin binding was confirmed by site-directed mutagenesis in which basic amino acids were replaced by alanine. These studies revealed that Lys-186 and Lys-187 are important for heparin binding of MBP-Fim2, whereas Arg-179 is not required. Peptides derived from H1 and H2 (pepH1 and pepH2) also showed heparin binding activity. Using a series of peptides, in each of which a different basic amino acid was substituted for alanine, we demonstrated that the structural requirements for heparin binding differ significantly among pepH1 and pepH2 peptides. A Pepscan analysis of Fim2 revealed regions outside H1 and H2 which bind heparin and showed that not only basic amino acids but also tyrosines may be important for binding to sulfated sugars. A comparison of the heparin binding regions of Fim2 with homologous regions of Fim3 and FimX, two closely related but antigenically distinct fimbrial subunits, showed that basic amino acids and tyrosines are generally conserved. The major heparin binding regions identified in Fim2 are part of epitopes recognized by human antibodies, suggesting that the heparin binding regions are exposed at the fimbrial surface and are immunodominant. Since B. pertussis fimbriae show weak serological cross-reactivity, the differences in primary structure in the heparin binding regions of Fim2, Fim3, and FimX may affect antibody binding but not heparin binding, allowing the bacteria to evade antibody-mediated immunity by switching the fimbrial gene expressed. 相似文献
108.
S Ren TF Kalhorn GB McDonald C Anasetti FR Appelbaum JT Slattery 《Canadian Metallurgical Quarterly》1998,64(3):289-301
Classical swine fever virus infection of pigs causes a severe leukopenia and immunosuppression. In the present study, the kinetics of virus infection, and identification of target cells for the virus in peripheral blood were analysed. Virus infection was often not detectable before 5-7 days p.i. A minority of animals yielded detectable infected cells at 3 days p.i., but < 5% PBMC. It was not until 10 days p.i. that this figure increased-to 35-70% PBMC depending on the animal. Detailed analysis of Ficoll-Hypaque-purified PBMC identified the major population to be SWC3+SWC8+CD14+MHCII- granulocytic cells. Microscopic observations determined that these low density granulocytic cells in the PBMC from CSFV infected animals were indeed immature cells. Both the low density granulocytic cells and monocytes were major targets for CSFV infection in the peripheral blood. This is the first demonstration that low density granulocytic cells dominate the blood leukocyte population during CSF, and that such cells are targets for virus infection. The present work also demonstrates that the leukocyte population changes, such as B lymphocyte depletion and the relative dominance of myeloid cells in the blood during CSF, occur before virus infection of the affected cells. Thus, the pathological mechanism therein is not a direct consequence of virus infection. 相似文献
109.
The water-soluble amide to an NH2-ended monomethoxypolyethyleneglycol (MPEG-NH2, molecular mass of about 2000) of the dipyrrinone xanthobilirubic acid (XBR, 1) and the bis-amides of mesobiliverdin-XIII alpha (MBV, 2) and mesobilirubin-XIII alpha (MBR, 3) have been prepared with high yields. Contrary to what is observed with biliverdin-IX alpha, 4, the enzymatic reduction of the mesobiliverdin derivative 2-MPEGA to the corresponding mesobilirubin 3-MPEGA by the soluble biliverdin reductase/NADPH system in pH 7.4 aqueous phosphate does not occur. In contrast, thiol addition to 2-MPEGA and to 4 under similar conditions is immediate, although this equilibrium is slightly less favourable for 2-MPEGA. These results enable us to discount the intrinsically low reactivity of 2-MPEGA towards thiols as the reason for its lack of enzymatic reduction, and suggest instead that this particular mesobiliverdin cannot fit properly into the enzyme binding site, either because of steric hindrance or the lack of the two propionic acid groups. 相似文献
110.
WI Bensinger KS Schiffman L Holmberg FR Appelbaum R Maziarz P Montgomery E Ellis S Rivkin P Weiden K Lilleby S Rowley S Petersdorf JP Klarnet W Nichols A Hertler R McCroskey CH Weaver CD Buckner 《Canadian Metallurgical Quarterly》1997,19(12):1183-1189
The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens. 相似文献