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991.
OBJECTIVES: Although pre-freeze and post-thaw semen quality in patients with cancer is poor, it is not clear whether lipid peroxidation affects semen quality. This study assessed (1) whether poor semen quality in patients with cancer is caused by lipid peroxidation, and (2) whether patient age or sperm motility is associated with lipid peroxidation. METHODS: Lipid peroxidation was measured by determining malonaldehyde levels using the thiobarbituric acid method. Malonaldehyde levels were measured in cryopreserved semen specimens from patients with testicular (n = 15) or nontesticular cancer (n = 16) and normal men (control subjects, n = 20). A computer-assisted semen analyzer was used to determine the sperm concentration and motility before and after cryopreservation. RESULTS: Malonaldehyde levels did not differ in frozen-thawed semen specimens among patients with testicular (25.90 +/- 1.00 nM/10(8) sperm/hr) or nontesticular cancer (24.48 +/- 1.66 nM/10(8) sperm/hr), and control subjects (24.86 +/- 1.43 nM/10(8) sperm/hr). Malonaldehyde levels did not correlate with post-thaw sperm motility or patient age in patients with testicular or nontesticular cancer. Post-thaw sperm motility from patients with testicular or nontesticular cancer was significantly lower than that in normal subjects. CONCLUSIONS: The poor post-thaw semen quality in patients with testicular or nontesticular cancer is not related to lipid peroxidation but may be caused by other factors such as sperm membrane stress induced during the freeze-thaw process.  相似文献   
992.
Evoked responses have not been studied in patients with acute severe hepatitis (ASH) with or without hepatic encephalopathy. This prospective study was undertaken to find out diagnostic as well as prognostic value of visual evoked responses (VER), and brain stem auditory evoked responses (BAER) in patients with ASH with or without encephalopathy. Visual evoked responses and BAER were studied in 20 patients (14 males and six females) with ASH. The patients were diagnosed as having severe hepatitis if acute hepatitis was associated with raised serum bilirubin and serum transaminases, and if they had a prothrombin time index of < 50%. After a detailed neuropsychiatric examination of each patient, the study sample was divided into two groups of 10 patients: ASH without encephalopathy (ASH-WOE), and ASH with encephalopathy (fulminant hepatic failure, FHF). The median P100 latencies of FHF patients were significantly increased compared with controls and patients in the ASH-WOE group. Abnormal P100 latencies, exceeding 95th percentile values of the controls, were present in one patient in the ASH-WOE group and six patients in the FHF group. The median interpeak latencies I-III, III-V and I-V were significantly prolonged in the FHF group. Interpeak latencies III-V were also increased significantly in patients in the ASH-WOE group. While abnormal BAER were seen frequently in both groups, VER abnormalities were largely confined to patients in the FHF group. In the FHF group, six out of 10 patients survived and exhibited clinical improvement in the status of hepatic encephalopathy. Evoked responses were repeated after 2-3 weeks of recovery in these patients and VER abnormalities showed a tendency to normalize, thereby suggesting a prognostic implication. The incidence of abnormal VER in hepatic encephalopathy complicating ASH far exceeded that of abnormal BAER. Markedly prolonged P100 latencies in FHF patients indicate poor prognosis.  相似文献   
993.
994.
OBJECTIVE: To document experience with directly observed chemoprophylaxis (DOPT) compared to self-administered isoniazid (INH) among aboriginal persons in British Columbia. DESIGN: DOPT was compared to self-administered delivery (SAD) over a 3-year period. All aboriginal persons who received INH chemoprophylaxis in British Columbia between 1992 and 1994 were evaluated. Therapy completion rates and adverse outcomes associated with SAD were compared with DOPT. Treatment allocation was by patient choice. RESULTS: Of 608 people who received INH prophylaxis, 443 received SAD (mean age 31.6 years) and 165 received DOPT (mean age 23.9 years). Two hundred and seventy (60.9%) SAD compared to 124 (75.2%) in the DOPT group completed 6 months of INH (P = 0.0011). The 12-month completion rates were 162/443 (36.6%) for the SAD group and 84/165 (50.9%) for the DOPT group (P = 0.0014). Adverse reactions requiring discontinuation of medication occurred in 13.5% of the patients on SAD and 9.7% of those receiving DOPT (P = 0.202). The most common reason cited for failure to complete therapy was non-cooperation in both groups. There were three deaths in the SAD group, one of which was due to suicide by self-ingestion of INH. CONCLUSIONS: These data demonstrate that in aboriginal people compliance with preventive therapy can be improved by DOPT. Non random allocation to treatment groups might have influenced our findings, and further prospective randomized trials and cost-effectiveness analyses are required.  相似文献   
995.
OBJECTIVE: To determine the benefit of screening for blunt carotid arterial injuries (BCI) in patients who are asymptomatic. SUMMARY BACKGROUND DATA: Blunt carotid arterial injuries have the potential for devastating complications. Published studies report 23% to 28% mortality rates, with 48% to 58% of survivors having permanent severe neurologic deficits. Most patients have neurologic deficits when the injury is diagnosed. The authors hypothesized that screening patients who are asymptomatic and instituting early therapy would improve neurologic outcome. METHODS: The Trauma Registry of the author's Level I Trauma Center identified patients with BCI from 1990 through 1997. Beginning in August 1996, the authors implemented a screening for BCI. Arteriography was used for diagnosis. Patients without specific contraindications were anticoagulated. Endovascular stents were deployed in the setting of pseudoaneurysms. RESULTS: Thirty-seven patients with BCI were identified among 15,331 blunt-trauma victims (0.24%). During the screening period, 25 patients were diagnosed with BCI among 2902 admissions (0.86%); 13 (52%) were asymptomatic. Overall, eight patients died, and seven of the survivors had permanent severe neurologic deficits. Excluding those dying of massive brain injury and patients admitted with coma and brain injury, mortality associated with BCI was 15%, with severe neurologic morbidity in 16% of survivors. The patients who were asymptomatic at diagnosis had a better neurologic outcome than those who were symptomatic. Symptomatic patients who were anticoagulated showed a trend toward greater neurologic improvement at the time of discharge than those who were not anticoagulated. CONCLUSIONS: Screening allows the identification of asymptomatic BCI and thereby facilitates early systemic anticoagulation, which is associated with improved neurologic outcome. The role of endovascular stents in the treatment of blunt traumatic pseudoaneurysms remains to be defined.  相似文献   
996.
Cell differentiation is frequently accompanied by alterations in the composition of gangliosides in the plasma membrane resulting from a regulation of the enzyme activities involved. The regulation of CMP-NeuAc:GM1 alpha2-3-sialyltransferase (ST-IV) and UDP-GalNAc:GM3 N-acetylgalactosaminyltransferase (Gal-NAc-T) by the degree of enzyme phosphorylation was analyzed by determination of the enzyme activity on incubation of NG108-15 cells with various protein phosphatase inhibitors (okadaic acid and orthovanadate) or protein kinase activators (phorbol ester and forskolin). Incubation with okadaic acid, but not with orthovanadate, inhibited the ST-IV activity to 45% of that of control cells with t(1/2) = 60 min for the inactivation reaction. This indicates a rapid hyperphosphorylation of ST-IV due to the inhibition of a serine/threonine-specific phosphatase. A similar rate of inactivation was found on stimulation of protein kinase C with phorbol ester. In contrast to ST-IV, the activity of GalNAc-T was increased on stimulation of intracellular phosphorylation systems. The fastest activation of GalNAc-T was achieved with forskolin, yielding up to 160% of the initial activity within 30 min of effector incubation. Up-regulation of GalNAc-T in conjunction with down-regulation of ST-IV by stimulation of phosphorylation is suggested to serve as a physiological mechanism to increase the concentration of GM1, which was found to be elevated in correlation with the cell density. This assumption was corroborated by metabolic labeling studies with radioactive ganglioside precursors indicating an enhancement of the relative amount of a-series gangliosides subsequent to GM3 on phosphorylation stimulation. In particular, the biosynthesis of GM1 was specifically elevated within 2 h of incubation with forskolin. We conclude from the overall data that the ganglioside composition during the cell differentiation of NG108-15 cells can be specifically regulated by both protein kinase A- and protein kinase C-related phosphorylation systems.  相似文献   
997.
Two samples of participants from the U.S.-Mexico Borderland (N = 185) versus Spain (N = 205) were compared on 16 Spanish-language neuropsychological measures. In most measures the two samples obtained similar results. There were some significant main effects of place of birth and some significant interactions between education and place of birth. Differences between the samples diminished with increasing levels of education. Within the Borderland sample, percent of life span spent in the U.S. and bilingual status were correlated with performance in some tests. Increased percent of life span spent in the U.S. was negatively correlated with performance on a Spanish word-generation task, and positively correlated with performance on the Wisconsin Card Sorting Test. Bilingual Borderland participants performed significantly better than monolingual speakers in learning a list of words. We suggest that the most likely causes for the observed interaction effects are documented regional differences in early SES-related nutrition, medical care, quality of educational experiences, and general socioeconomic conditions.  相似文献   
998.
OBJECTIVES: Capacitation and acrosome reaction are prerequisites for fertilization. However, in vitro capacitation is not necessary for an agonist-induced acrosome reaction. We studied whether in vitro capacitation is important in spontaneous acrosome reaction and analyzed how capacitation before cryopreservation influences the acrosomal status of thawed spermatozoa. METHODS: Semen specimens from normal donors (n = 15) were processed by the swim-up technique and divided into two aliquots. One aliquot was capacitated (capacitation induced) for three hours by incubation in a modified-BWW medium with 3% HSA at 37 degrees C under 5% carbon dioxide. The other aliquot did not receive any treatment. Both aliquots were analyzed by CASA to assess the capacitation status of the spermatozoa and then cryopreserved. Spontaneous acrosome reaction was assessed by FITC-PNA lectin before and after cryopreservation. Sperm viability was measured using Hoechst-33258 stain. RESULTS: Before freezing, the frequency of spontaneous acrosome reaction was higher in the capacitation-induced sperm preparation (median, 20.5% [interquartile range, 17.2-37.8]) than in swim-up-induced specimens (median, 10.6% [range, 4.8-23.2]; P <.001). The percentage of viable cells showing acrosome reaction increased after cryopreservation in both swim-up-induced specimens (median, 241.4% [interquartile range, 37.1-678.6]; P <.001) and capacitation-induced specimens (median, 48.2% [range, 6.1-63.3]; P = 0.002). Although this increase was higher in the swim-up-induced specimens (P = 0.002), frequency of postthaw spontaneous acrosome reaction was similar in both groups (P = 0.18). CONCLUSIONS: We conclude that sperm capacitation significantly optimizes the acrosome reaction. However, a small proportion of normal spermatozoa do not require capacitation to undergo spontaneous acrosome reaction in vitro. After cryopreservation, the percentage of spermatozoa that had intact acrosomes was similar in both groups, despite the fact that one aliquot underwent prefreeze capacitation. These findings suggest that the acrosome reaction may involve complex mechanism(s) rather than a physiological change induced by capacitation.  相似文献   
999.
No curative therapy is available for malignant gliomas. We have discovered that human glioblastoma cells express high affinity interleukin-4 receptor (IL-4R), which is an attractive target for receptor-directed IL-4 toxin therapy. The IL-4 toxin, IL-4(38-37)-PE38KDEL, is a fusion protein containing translocation and enzymatic domains of Pseudomonas exotoxin and a circularly permuted human IL-4. The IL-4 toxin binds specifically to the IL-4R and is highly cytotoxic to glioblastoma cells, as determined by clonogenic and protein synthesis inhibition assays. Intratumoral administration of the IL-4 toxin given on alternate days for 3-4 doses into U251 glioblastoma flank tumors in nude mice, showed a complete remission of small (approximately 13 mm3) and large (approximately 60 mm3) tumors in all animals, without any evidence of toxicity. A significant antitumor activity was also observed when the IL-4 toxin was administered via i.p. and i.v. routes. These results demonstrate that the IL-4 toxin may be a new therapeutic drug for the treatment of human glioblastoma. Therefore, we have begun a Phase I clinical trial with IL-4(38-37)-PE38KDEL for treatment of human glioblastoma.  相似文献   
1000.
The remarkable anticancer drug dolastatin 10 (1a) from the Indian Ocean sea hare Dolabella auricularia is currently undergoing phase I clinical trials. Thirty-eight new structural modifications of this unusual peptide have been synthesized and evaluated against a variety of human and murine cancer cell lines, and for their ability to inhibit tubulin polymerization and vinblastine and GTP binding to tubulin. Dolastatin 10 and one structural modification was found to have antifungal activity, while one other structural modification of the parent compound exhibited antibacterial activity. Some of the new peptides approximated the antineoplastic potency of dolastatin 10, especially those based on replacement of the Doe unit with Met, Phe or an appropriately substituted phenylethylamide.  相似文献   
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