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951.
The effect of follicle stimulating hormone and epidermal growth factor on the developmental capacity of in-vitro matured mouse oocytes 总被引:2,自引:4,他引:2
This study investigates the effects of follicle stimulating hormone (FSH)
or epidermal growth factor (EGF) on the development of mouse oocytes
matured in vitro. The data show that addition of FSH or EGF does not
significantly increase the proportion of oocytes maturing to metaphase II
but does increase the ability of these oocytes to cleave to the 2-cell
stage after fertilization. After transfer of 2-cell embryos to
pseudopregnant recipients, 64-78% of the embryos implanted, which was
significantly reduced compared to embryos from in-vivo matured controls
(89%). Fewer fetuses at day 14 of gestation were produced from embryos
derived from oocytes matured in basal conditions (26%), or in the presence
of EGF (32%), compared to oocytes matured in vivo (64%) or in the presence
of FSH (58%). Examination of polar bodies and pronuclei of oocytes matured
in vitro suggests that an increase in the rate of triploidy may be partly
responsible for the increased fetal loss after maturation in the absence of
FSH. This study shows that the fertilization rate after in-vitro maturation
can be improved by FSH and EGF and that subsequent embryonic development is
improved specifically by FSH.
相似文献
952.
M. Seed F. Mailly D. Vallance E. Doherty A. Winder P. Talmud S. E. Humphries 《Journal of molecular medicine (Berlin, Germany)》1994,72(2):100-106
The aetiology of familial combined hyperlipidaemia remains obscure, with both genetic and environmental factors contributing to the phenotype, which is frequently associated with premature coronary heart disease. We have studied lipoprotein lipase (LPL) activity and hepatic lipase (HL) activity in patients with coronary heart disease to determine whether variation in lipase activities contributes to this phenotype. Forty-one patients (mean age 50 years; 30 male) were selected on the basis of cholesterol levels above 6.5 mmol/l and triglyceride levels above 2.2 mmol/1, with apoprotein B values over the 90th percentile. There was a family history of premature coronary heart disease in 78% and a personal history in 64%, at mean age 44, the patient group therefore predominantly corresponded to the common definition of familial combined hyperlipidaemia, appropriate in the absence of molecular markers. None of the patients was diabetic; hypertension and smoking were not over represented. Blood samples were taken following intravenous administration of heparin (100IU/kg body wt), and LPL and HL activities were measured. Mean post-heparin LPL was significantly lower in patients than controls 10 min after heparin administration (2.98 ± 1.04 and 3.86 ± 0.93 mol ml-1 h-1, respectively, P = 0.001), and 37% patients had values below the 10th percentile of controls. Both male and female patients had significantly higher HL activities than their respective controls at 5, 10, 20 and 30 minutes postheparin. As expected, both female patients and controls had lower HL activities than males, although this sex difference did not reach statistical significance in the patient group. Mean lipid and lipoprotein results were: cholesterol 8.2 mmol/1; triglycerides 4.2 mmol/l; high-density lipoprotein cholesterol 0.90 mmol/1; apoprotein Al 122 mg/dl; apoprotein B 171 mg/dl; lipoprotein (a) 23 mg/dl (median 10 mg/dl). High-density lipoprotein cholesterol and triglycerides were negatively correlated (r = -0.26, P = 0.05). HL was significantly related to body mass index at all time points whereas the negative correlation between post-heparin LPL and body mass index was significant only 30 min after heparin administration. Post-heparin LPL was only weakly correlated with triglycerides 10 and 20 min after heparin administration. These lipid and lipoprotein results are clearly potentially atherogenic as indicated by the extent of premature coronary heart disease in the group described. A decrease in LPL activity may contribute to this pattern.Abbreviations FCHL
familial combined hyperlipidaemia
- CHD
coronary heart disease
- LPL
lipoprotein lipase
- HL
hepatic lipase
- HDL
high-density lipoprotein
- VLDL
very low density lipoprotein;
- apo
apoprotein
- TG
triglyceride
- BMI
body mass index
Correspondence to: M. Seed 相似文献
953.
Endurance exercise training produces major adaptations in hormonal and metabolic responses to exercise. This study was designed to determine whether the differences in hormone response persist in the fasted condition when liver glycogen is depleted. Rats were run on a motor-driven rodent treadmill 5 days/wk for periods up to 2 h/day for 10 wk. Trained and nontrained rats were then fasted 24 h and were run for periods ranging from 0- to 60 min. At the end of 60 min of exercise muscle glycogen was higher in trained rats (2.9 +/- 0.3 vs. 1.1 +/- 0.1 mg/g). Blood glucose was maintained at higher levels in trained rats throughout the course of the exercise (3.2 +/- 0.1 vs. 2.3 +/- 0.1 mM after 60 min). Plasma concentrations of glucagon and epinephrine increased in both groups during the exercise but were significantly lower in trained animals. Differences between trained and nontrained animals in stress hormone responses to exercise persist in the fasted state and appear to be a consequence of the capacity of trained animals to maintain higher blood glucose levels. 相似文献
954.
Severe aplastic anemia: a prospective study of the effect of early marrow transplantation on acute mortality 总被引:17,自引:5,他引:17
Camitta BM; Thomas ED; Nathan DG; Santos G; Gordon-Smith EC; Gale RP; Rappeport JM; Storb R 《Blood》1976,48(1):63-70
A prospective randomized trial of therapy for severe aplastic anemia was designed to compare early bone marrow transplantation with conventional treatments. All patients with a sibling matched at the major histocompatibility region were transplanted. Transplantation was performed with 17-100 (median 33) days of original diagnosis. Conventional treatments included transfusion support with or without androgens. Twenty-four of 36 patients intered on the transplant arm are alive after 4-20 (median 9) mo with full marrow reconstitution. Only two are limited by chronic graft-versus-host disease. In contrast only 12 of 31 conventionally treated patients are alive. Six of these survivors have improved, five incompletely. The 19 nontransplant deaths have occurred within 1-11 (median 3) mo of diagnosis. Compared to nontransplant regimens, early transplantation more effectively restores normal marrow function and decreases the acute mortality of severe marrow aplasia (p = 0.006). Pending longer follow-up, early marrow transplantation appears to be the most effective available treatment for severe aplastic anemia. 相似文献
955.
Patients with diffuse lymphoblastic lymphoma (which includes convoluted lymphocytic lymphoma) with mediastinal involvement have predictable progression of disease to a leukemic phase that is cytologically indistinguishable from acute lymphoblastic leukemia (ALL). Therefore we treated 12 patients with diffuse lymphoblastic lymphoma involving the mediastinum with therapy that is effective in ALL. Treatment consisted of intermittent combination chemotherapy with adriamycin and preventive central nervous system therapy (craniocervical irradiation and intrathecal methotrexate). Mediastinal irradiation was given either for initial respiratory distress or to patients who had incomplete regression of disease following induction chemotherapy. Eleven patients achieve complete remission. With a median follow-up of 41 mo, and using life table analysis, 86% of these patients have remained in continuous complete remission. The results of this study demonstrate the efficacy of treating diffuse lymphoblastic lymphoma with mediastinal presentation as a disseminated lymphoid malignancy. 相似文献
956.
Combinations of recombinant colony-stimulating factors are required for optimal hematopoietic differentiation in serum-deprived culture 总被引:5,自引:1,他引:5
Previous in vitro investigations on enriched human hematopoietic progenitors have led to the conclusion that the purified recombinant multipoietins, interleukin 3 (IL-3) and granulocyte-macrophage colony- stimulating factor (GM-CSF) can alone induce the formation of colonies from a variety of multipotent and lineage committed progenitors. Since fetal calf serum was included in these cultures and itself might contain growth factors or other cofactors, we re-examined the actions of the CSFs in serum-deprived conditions. Results show that both the multipoietins are inadequate stimuli of colony formation. At maximal concentrations IL-3 alone induces only 25% of the granulocyte and macrophage colony-forming units (CFU-G and CFU-M) produced by a T-cell conditioned medium that contains a mixture of CSFs. When IL-3 was added at the initiation of the cultures and erythropoietin (ep), G-CSF, or M- CSF added on day 3, almost full recovery of erythroid, granulocytic, and monocytic colonies, respectively, was obtained. Similar results were obtained with GM-CSF except that fewer erythroid colonies were recovered at high concentrations, and almost maximal CFU-M proliferation could be induced. These results show that in serum- deprived conditions, the multipoietins must be combined with lineage specific CSFs for full progenitor expression. 相似文献
957.
M. Fiegl R. Stauder M. Steurer M. Mian G. Hopfinger Y. Brychtova C. Skrabs A. Zabernigg F. Schmid F. Haslbaur G. Winder A. Walder A. Lang D. Voskova R. Greil J. Mayer G. Gastl 《Annals of hematology》2014,93(2):267-277
This retrospective study evaluated the benefit of alemtuzumab monotherapy in unselected patients with advanced B-cell chronic lymphocytic leukemia (CLL) and prolymphocytic leukemia (B-PLL) to definitely describe the impact of this antibody in clinical routine use. Data were collected from 208 consecutive, mainly pretreated, patients with CLL (n?=?202), and B-PLL (n?=?6) who had received alemtuzumab. Response, progression-free survival (PFS), and overall survival (OS) in various settings were assessed, and toxicities were documented. In these routine patients, a comparably low cumulative dose of alemtuzumab (median, 403 mg) was applied. In CLL, overall response rate was 32 %, and various pre-therapeutic parameters were predictive for inferior response, among them, the prior administration of ≥3 therapy lines (P?<?0.001), refractoriness to fludarabine (P?=?0.002), and bulky lymphadenopathy (P?=?0.003). PFS and OS after start of alemtuzumab were 6.2 and 21.0 months, respectively. Bulky lymphadenopathy was the prominent risk factor for both inferior PFS (P?<?0.001) and OS (P?=?0.002). In B-PLL, four patients experienced a fatal outcome, whereas two patients had some benefit with alemtuzumab. The main adverse effects were CMV reactivation (20 %) and a broad spectrum of infections, which together were the main reasons for treatment interruption and/or premature termination. In conclusion, alemtuzumab administered even at low dose levels was effective but overall considerably toxic in routine CLL patients. We emphasize that alemtuzumab remains an important therapeutic option in subsets of CLL patients. 相似文献
958.
Gerson Suarez‐Cedeno MD Thomas Winder PhD Margherita Milone MD PhD 《Muscle & nerve》2014,49(4):607-610
Introduction: DNAJB6 mutations cause an autosomal dominant myopathy that can manifest as limb‐girdle muscular dystrophy (LGMD1D/1E) or distal‐predominant myopathy. In the majority of patients this myopathy manifests in adulthood and shows vacuolar changes on muscle biopsy. Methods: Clinical, electrophysiological, pathological, and molecular findings are reported. Results: We report a 56‐year‐old woman, who, like 3 other family members, became symptomatic in childhood with slowly progressive limb‐girdle muscle weakness, normal serum creatine kinase (CK) values, and myopathic electromyographic findings. Muscle biopsy showed vacuolar changes and congophilic inclusions, and molecular analysis revealed a pathogenic mutation in the DNAJB6 gene. Differences and similarities with previously described cases are assessed. Conclusions: Childhood‐onset of DNAJB6 myopathy is more frequent than previously believed; congophilic inclusions may be present in the muscle of these patients. Muscle Nerve 49:607–610, 2014 相似文献
959.
Toxicity of the antimicrobial compound triclosan and formation of the metabolite methyl-triclosan in estuarine systems 总被引:2,自引:0,他引:2
Delorenzo ME Keller JM Arthur CD Finnegan MC Harper HE Winder VL Zdankiewicz DL 《Environmental toxicology》2008,23(2):224-232
Triclosan, a commonly used antimicrobial compound, has been measured in aquatic systems worldwide. This study exposed marine species to triclosan to examine effects primarily on survival and to investigate the formation of the degradation product, methyl-triclosan, in the estuarine environment. Acute toxicity was assessed using the bacterium Vibrio fischeri, the phytoplankton species Dunaliella tertiolecta, and three life stages of the grass shrimp Palaemonetes pugio. P. pugio larvae were more sensitive to triclosan than adult shrimp or embryos. Acute aqueous toxicity values (96 h LC50) were 305 microg/L for adult shrimp, 154 microg/L for larvae, and 651 microg/L for embryos. The presence of sediment decreased triclosan toxicity in adult shrimp (24 h LC50s were 620 microg/L with sediment, and 482 microg/L without sediment). The bacterium was more sensitive to triclosan than the grass shrimp, with a 15 min aqueous IC50 value of 53 microg/L and a 15 min spiked sediment IC50 value of 616 microg/kg. The phytoplankton species was the most sensitive species tested, with a 96 h EC50 value of 3.55 microg/L. Adult grass shrimp were found to accumulate methyl-triclosan after a 14-day exposure to 100 microg/L triclosan, indicating formation of this metabolite in a seawater environment and its potential to bioaccumulate in higher organisms. Triclosan was detected in limited surface water sampling of Charleston Harbor, SC at a maximum concentration of 0.001 microg/L, substantially lower than the determined toxicity values. These findings suggest triclosan poses low acute toxicity risk to estuarine organisms; however, the potential for chronic, sublethal, and metabolite effects should be investigated. 相似文献
960.
Introduction The medical literature describes disparity in colonoscopy performance. This randomised, controlled study aimed to characterise
the impact of feedback on colonoscopy performance among gastroenterology (GI) trainees.
Methods Gastroenterology trainees of similar experience levels who independently performed 581 colonoscopies over the study period
were randomised to receive feedback/no feedback on their colonoscopy performance.
Results Baseline colonoscopy performance was similar in both groups. Following feedback, caecal intubation improved by 10.5% (from
72.9 to 83.4%, p = 0.04) in the feedback group and declined by 6.1% (from 78 to 71.9%, p = 0.2) in the control group; polyp detection improved by 5.1% (from 12.9 to 18.0%, p = 0.2) in the feedback group and by 2.9% (from 16.7 to 19.6%, p = 0.5) in the control group.
Conclusions Systematic feedback appears to enhance colonoscopy performance among GI trainees. 相似文献