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101.
Treatment variables in relation to oocyte maturation: Lessons from a clinical micromanipulation-assisted in vitro fertilization program 总被引:1,自引:0,他引:1
Ori M. Avrech Gil A. Goldman Onit Rufas Anat Stein Shoshana Amit Israel Yoles Haim Pinkas Benjamin Fisch 《Journal of assisted reproduction and genetics》1997,14(6):337-342
Objective: In an effort to understand the mechanism underlying the improved pregnancy rate observed in IVF cycles when gonadotropin-releasing
hormone analogues (GnRH-a) are applied, we investigated a possible relationship between treatment variables and oocyte-nuclear
maturity.
Design: Nuclear maturity was retrospectively assessed in cumulus-free, denuded oocytes, obtained from women undergoing micromanipulation-assisted
IVF treatment following controlled ovarian hyperstimulation with GnRH-a and menotropins.
Setting: The setting was the infertility and IVF unit of a tertiary academic medical center.
Participants: Two hundred twenty-one patients underwent 435 treatment cycles.
Main Outcome Measure: This was the proportion of germinal vesicle-intact immature (GVII) oocytes.
Results: One hundred fifty-four of the 3520 oocytes studied (4.4%) were in the GVII stage. These oocytes were found in 66 of the treatment
cycles (15.2%) and in 54 of the patients (24.4%). Cycles in which GVII oocytes were detected did not differ from those in
which all the aspirated oocytes were mature in the following respects: patient age, type and duration of infertility, controlled
ovarian hyperstimulation protocol and time of ovum pickup. However, the GVII group was characterized by a significantly higher
peak estradiol level, as well as a higher number of mature follicles visualized sonographically (diameter, >14 mm) and oocytes
retrieved.
Conclusions: Comparing the present findings with previously published data, it appears that the inclusion of GnRH-a in the stimulation
regimen is associated with a lower proportion of immature oocytes. A higher occurrence of oocyte-nuclear immaturity is apparently
associated with a significantly better ovarian response to stimulation. The high incidence of immature oocytes observed in
patients with normospermic partners and low fertilization rates in previous cycles may suggest that the fertilization failure
in some of these cases is due to oocyte, rather than sperm, dysfunction. 相似文献
102.
Antonio Vivi Maria Tassini Hava Ben-Horin Gil Navon Ofer Kaplan 《Breast cancer research and treatment》1997,43(1):15-25
Lonidamine (LND) is a relatively new anti-cancer drug,and several clinical trials have indicated that it may be effectivein combinations with other therapeutic modalities. LND isclassified within the metabolic inhibitor agents. Multidrugresistance (MDR) phenomenon is often associated with increasedenergy requirements, and enhanced glycolysis rate. These studieswere performed to delineate the mechanism of action of LNDon MDR human breast cancer cells, and to investigate whetherLND as a single agent, or in combination with anotheranti-metabolism drug, 2-deoxyglucose (2-DG), may be usefulagainst MDR tumors. The effects of LND on intact perfuseddrug-sensitive (WT) and 33-fold resistant to Adriamycin(Adr) MCF-7 cells, embedded in alginate micro capsules, were continuouslymonitored by 31P and 13C nuclearmagnetic resonance (NMR) spectroscopy. 31PNMR studies showed that LND induced intracellular acidificationand depletion of NTP in both WT and Adr cells. However, pH and NTPlevels decreased less in the Adr cells than in the WT cells(p < 0.05 for both parameters). 13CNMR demonstrated that LND inhibited lactate transport,and lactate signals were elevated in both cell lines. However, theintracellular lactate levels increased to a greater extentin the WT than in the Adr cells (p < 0.05).There were major differences in the effects of LND onmetabolism between sensitive and resistant cells.While LND enhanced glucose uptake in the WT cells, and itsadministration was followed by continuous increase oflactate signal, both processes were not affected by LNDin the Adr cells. 2-DG is a glucose analogue that inhibitsboth cellular uptake and utilization of glucose, leading to cell starvation. Combined treatment with LND and2-DG yielded at best additive, but not synergistic,cellular toxicity, and the metabolic effects of LNDwere attenuated by 2-DG. These results showed that the principalmechanism of action of LND is inhibition of lactate transportleading to intracellular lactate accumulation and acidificationin both WT and Adr cells. The Adr cells were only 2-fold resistantto LND (compared to the WT cells), and since cellular uptakeof alkaloid chemotherapy is improved in acidic environment,LND may have a role in the treatment protocols of MDR tumors,especially when given as the initial means for inductionof intracellular acidification. 相似文献
103.
García-Aguado R Gil F Barcia JA Aznar J Hostalet F Barberá J Grau F 《Anesthesia and analgesia》2000,90(4):894-898
We explored the effect of fibrin glue injection at the site of dural puncture on cerebrospinal fluid (CSF) leakage in a swine model. Pigs were subjected to a lumbar dural CSF puncture in the sitting position with a 17-gauge Tuohy needle. Fibrin glue 1.4 mL was injected through the same needle into the epidural space. Evans blue dye was infused through the cisterna magna 15 min later, and the appearance of dyed CSF through the skin puncture and along the needle trajectory to the dura was inspected and categorized. In seven of eight animals, the CSF leak was sealed with fibrin glue. Control animals were injected with 1.4 mL saline. A sham operation group of animals underwent cisternal dye infusion without a lumbar puncture. CSF pressure at the cisterna magna was recorded throughout the procedure. No significant differences in the leakage indicators were found between the fibrin glue-injected and sham-operated group, whereas both groups showed significant differences with respect to the control group. The fibrin glue seal was effective against CSF pressures of 24.5 [17-31] cm H(2)O. We conclude that percutaneously injected fibrin glue is effective in stopping CSF leaks after dural puncture in this animal model. IMPLICATIONS: In this swine study, we repaired a cerebrospinal fluid leak after a dural puncture by percutaneously injecting tissue adhesive. The technique of percutaneous injection of fibrin glue seems promising for the prophylaxis of headache associated with cerebrospinal fluid leakage, and may be an alternative to an epidural blood patch. 相似文献
104.
Acute hypoxic hypoxia transiently reduces GABA(A) binding site number in developing chick optic lobe
Rodríguez Gil DJ Viapiano MS Fiszer de Plazas S 《Brain research. Developmental brain research》2000,124(1-2):67-72
The Central Nervous System is known to be critically affected in the prenatal-perinatal period by hypoxic-ischemic insults, which produce several disorders such as loss of neural projections, increased susceptibility to seizures, apoptosis and an imbalance in normal activity of glutamatergic and GABAergic neurones, resulting in acute cell excitotoxicity. The aim of the present work was to establish a chick embryo model of normobaric acute hypoxic hypoxia as well as to evaluate modifications in GABA(A) receptor complex from chick optic lobe, that may result from this injury. Fertile chicken (Gallus gallus domesticus) eggs from White Leghorn were incubated and at embryonic days (ED) 12 to 18, subjected to a stream of 8%O(2)/92%N(2) during1 h, and then were either returned to their shelves in the incubator for recovery, or immediately processed for biochemical studies. Hypoxic treatment produced a significant age dependent reduction in GABA binding sites showing the greatest decrease at the earliest stages studied (ED12-ED16). Saturation curves of GABA binding performed at ED12 showed a decrease in B(max), (control, 5.48+/-0.20, hypoxic, 3.90+/-0.39 pmol/mg protein), but no significant change in K(d). Following 48 h in normoxic atmosphere post-hypoxia reduction in [3H]GABA binding was reversed. Pharmacological properties of GABA(A) receptor at ED12 showed that positive allosteric modulation effects of the steroid 3alpha-hydroxy-5alpha-pregnan-20-one and the barbiturate pentobarbital sodium were enhanced by the treatment. This model of acute prenatal hypoxic hypoxia produced marked alterations in inhibitory CNS neurotransmission that proved reversible and age dependent. 相似文献
105.
106.
Association of serotonin 5-HT2A receptor binding and the T102C polymorphism in depressed and healthy Caucasian subjects. 总被引:4,自引:0,他引:4
Vadim D Khait Yung-yu Huang Gil Zalsman Maria A Oquendo David A Brent Jill M Harkavy-Friedman J John Mann 《Neuropsychopharmacology》2005,30(1):166-172
Serotonin 5-HT2A receptor (5-HT2A) binding is reported to be altered in individuals with suicidal behavior, mood disorders, and aggressive-impulsive traits. Genetic association with major depression, suicidal behavior, and aggressive-impulsive traits has not been established. This study examines the possible association of the 5-HT2A gene C102T polymorphism with the receptor binding kinetics, and clinical overt phenotypes. The study population included 63 healthy volunteers and 152 subjects with mood disorders, 56 of whom had a history of suicide attempts. All were Caucasian. Platelet 5-HT2A binding kinetics (Bmax and KD) were assayed and adjusted for seasonal variation. All subjects were genotyped for the T102C polymorphism. Clinical phenotype was determined by structured clinical interview. The TT genotype was associated with higher Bmax in all subjects (F=3.53, df=2,211; p=0.03), controlling for diagnosis. Bonferroni-adjusted post hoc testing showed higher binding in the TT compared with TC genotype in the control group (F=7.56, df=2,60, p=0.001), but not in the mood-disordered subjects. No difference was found in genotype and allele distribution between the mood-disordered subjects, with and without suicide attempt history, and controls. Bmax was not related to a diagnosis of mood disorders. The TT genotype appears associated with higher platelet 5-HT2A Bmax in the healthy population, but this genotypic effect appears absent in mood disorders and unrelated to psychopathology. 相似文献
107.
Javier Sastre Eugenio Marcuello Bartomeu Masutti Matilde Navarro Silvia Gil Antonio Antón Albert Abad Enrique Aranda Joan Maurel Manuel Valladares Inmaculada Maestu Alfredo Carrato José María Vicent Eduardo Díaz-Rubio 《Journal of clinical oncology》2005,23(15):3545-3551
PURPOSE: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients. PATIENTS AND METHODS: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion. RESULTS: By intent-to-treat analysis, in 85 assessable patients, the objective response rate was 35% (95% CI, 25% to 46%), and stable disease was 33% (95% CI, 23% to 44%). Median time to progression was 8.0 months (95% CI, 6.0 to 10.0 months), and median overall survival time was 15.3 months (95% CI, 13.8 to 16.9 months). Toxicity was moderate. Grade 3 and 4 neutropenia, diarrhea, and asthenia were observed in 21%, 17%, and 13% of patients, respectively. Only one case of neutropenic fever occurred. There were two toxic deaths, one was a result of grade 4 diarrhea and acute kidney failure, and the other was a result of massive intestinal hemorrhage in the first cycle. The study of prognostic factors did not reveal any predictive factor of response. Response to treatment and baseline lactate dehydrogenase were the main factors conditioning progression-free and overall survival. CONCLUSION: Twice a month continuous-infusion CPT-11 combined with FU is a valid therapeutic alternative for elderly patients in good general condition. 相似文献
108.
109.
Natalia Curto-García Julio García-Suárez Marta Callejas Chavarria Juan José Gil Fernández Yolanda Martín Guerrero Elena Magro Mazo Shelly Marcellini Antonio Luis Miguel Juárez Isabel Gutierrez Juan José Arranz Irene Montalvo Carmen Elvira Pilar Domínguez María Teresa Díaz Carmen Burgaleta 《Supportive care in cancer》2016,24(1):93-101
110.
The air in Santiago, Chile, is among the most highly polluted in the world. Due to the high levels of pollutants and the high incidence of respiratory diseases, especially in the most susceptible groups, Santiago has been declared a saturated zone for PM10, O3, and CO. The aim of this work was to investigate polycyclic aromatic hydrocarbon levels and mutagenic activity of Santiago's fine and coarse fractions of inhalable particles. The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined by highperformance liquid chromatography in organic extracts from respirable particles (OERP). Respirable particulate matter (fine and coarse) contains high levels of PAHs including six mutagenic ones classified by the IARC as carcinogenic, which represented at least 45% of the total PAH concentration. A seasonal effect was observed, with higher values in months with lower temperatures. Although a significant decline of PAH levels in OERP was observed in the last years, the levels of carcinogenic PAHs are still higher than those reported in cities of the United States, Australia, and Europe. OERP were highly mutagenic and contained direct and indirect mutagens, which produced both frameshift and base substitution mutations in Salmonella typhimurium. In addition, organic extracts from total suspended particles were also highly mutagenic at the tk locus in h1A1v2 human lymphoblasts in culture. In spite of the important decrease in PAHs in the period 1991–1996, direct mutagenic response has not changed significantly, suggesting that the levels of direct mutagenic pollutants (e.g., nitroarenes) have not decreased considerably during the last years. These results suggest a risk for Santiago's inhabitants since pollutants adsorbed in inhalable particles are highly mutagenic and can damage DNA. 相似文献