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31.
32.
Oocyte retrieval in a stimulated in-vitro fertilization treatment cycle was
unsuccessful when inadvertently carried out 12 h after the administration
of human chorionic gonadotrophin (HCG) injection. Repeat follicular
aspiration at 36 h post-HCG injection recovered 20 oocytes, out of which 16
metaphase-II eggs were subjected to intracytoplasmic sperm injection and
eight became fertilized. Uterine transfer of three cleaving embryos
resulted in a singleton pregnancy which went to term and a healthy female
infant was delivered. Our experience shows that in addition to issues of
HCG bioavailability to the developing follicles, the temporal relationship
between HCG administration (or the luteinizing hormone surge) and
follicular aspiration is also an important consideration in the
determination of the aetiology of the empty follicle syndrome.
相似文献
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Mechanism of action of novel NO-releasing furoxan derivatives of aspirin in human platelets 下载免费PDF全文
Turnbull CM Cena C Fruttero R Gasco A Rossi AG Megson IL 《British journal of pharmacology》2006,148(4):517-526
Incorporation of a nitric oxide (NO)-releasing moiety in aspirin can overcome its gastric side effects.We investigated the NO-release patterns and antiplatelet effects of novel furoxan derivatives of aspirin (B8 and B7) in comparison to existing antiplatelet agents. Cyclooxygenase (COX) activity was investigated in purified enzyme using an electron paramagnetic resonance-based technique. Concentration-response curves for antiplatelet agents +/- the soluble guanylate cyclase inhibitor, ODQ (50 microM) were generated in platelet-rich plasma (PRP) and washed platelets (WP) activated with collagen using turbidometric aggregometry. NO was detected using an isolated NO electrode. The furoxan derivatives of aspirin (B8, B7) and their NO-free furazan equivalents (B16, B15; all 100 microM) significantly inhibited COX activity (P < 0.01; n = 6) in vitro and caused aspirin-independent, cGMP-dependent inhibition of collagen-induced platelet aggregation in WP. B8 was more potent than B7 (PRP IC(50) = 0.62 +/- 0.1 microM for B8; 400 +/- 89 microM for B7; P < 0.0001. WP IC(50)s = 0.6 +/- 0.1 and 62 +/- 10 microM, respectively). The NO-free furazan counterparts were less potent antiplatelet agents (WP IC(50)s = 54 +/- 3 microM and 62 +/- 10 microM, respectively; P < 0.0001, B8 vs B16). Of the hybrids investigated, only B8 retained antiplatelet activity in PRP.NO release from furoxan-aspirin hybrids was undetectable in buffer alone, but was accelerated in the presence of either plasma or plasma components, albumin (4%), glutathione (GSH; 3 microM) and ascorbate (50 microM), the effects of which were additive for B7 but not B8. NO generation from furoxans was greatly enhanced by platelet extract, an effect that could largely be explained by the synergistic effect of intracellular concentrations of GSH (3 mM) and ascorbate (1 mM). We conclude that the decomposition of furoxan-aspirin hybrids to generate biologically active NO is catalysed by endogenous agents which may instil a potential for primarily intracellular delivery of NO. The blunting of the aspirin effects of furoxan hybrids is likely to be due to loss of the acetyl moiety in plasma; the observed antiplatelet effects are thereby primarily mediated via NO release. Compounds of this class might represent a novel means of inhibiting platelet aggregation by a combination of NO generation and COX inhibition. 相似文献
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1. Nitric oxide (NO) is a potent inhibitor of platelet activation, that inhibits the agonist-induced increase in cytosolic Ca2+ concentration through both cGMP-dependent and independent pathways. However, the NO-related (NOx) species responsible for cGMP-independent signalling in platelets is unclear. We tested the hypothesis that extracellular NO, but not NO+ or peroxynitrite, generated in the extracellular compartment is responsible for cGMP-independent inhibition of platelet activation via inhibition of Ca2+ signalling. 2. Concentration-response curves for diethylamine diazeniumdiolate (DEA/NO; a spontaneous NO generator), S-nitroso-N-valerylpenicillamine (SNVP; an S-nitrosothiol) and 3-morpholinosydnonomine (SIN-1; a peroxynitrite generator) were generated in platelet-rich plasma (PRP) and washed platelets (WP) in the presence and absence of a supramaximal concentration of the soluble guanylate cyclase inhibitor, ODQ (20 microM). All three NOx donors displayed cGMP-independent inhibition of platelet aggregation in PRP, but only DEA/NO exhibited cGMP-independent inhibition of aggregation in WP. 3. Analysis of NO generation using an isolated NO-electrode revealed that cGMP-independent effects coincided with the generation of substantial levels of extracellular NO (>40 nM) from the NOx donors. 4. Reconstitution of WP with plasma factors indicated that the copper-containing plasma protein, caeruloplasmin (CP), catalysed the release of NO from SNVP, while Cu/Zn superoxide dismutase (SOD) unmasked NO generated from SIN-1. The increased generation of extracellular NO correlated with a switch to cGMP-independent effects with both NOx donors. 5. Analysis of Fura-2 loaded WP revealed that only DEA/NO inhibited Ca2+ signalling in platelets via a cGMP-independent mechanism. However, preincubation of SNVP and SIN-1 with CP and SOD, respectively, induced cGMP-independent inhibition of intraplatelet Ca2+ trafficking by the NOx donors. 6. Taken together, our data suggest that extracellular NO (>40 nM) is required for cGMP-independent inhibition of platelet activation. Plasma constituents may play an important pharmacological role in activating cGMP-independent signalling by S-nitrosothiols or peroxynitrite generators. 相似文献
38.
JAE HYUNG PARK
B.Sc. HUI‐NAM PAK
M.D. Ph.D. EUN JEOUNG CHOI M.D. JIN KUN JANG M.D. SOOK KYOUNG KIM
M.Sc. DONG HOON CHOI
M.D. Ph.D. JONG IL CHOI M.D. CHUN HWANG M.D. YOUNG‐HOON KIM
M.D. Ph.D. 《Journal of cardiovascular electrophysiology》2009,20(12):1349-1356
Background: Long‐standing atrial fibrillation (AF) changes left atrial (LA) morphology, and the LA size is related to recurrence after radiofrequency catheter ablation (RFCA). We hypothesize that LA morphology, based on embryological origin, affects the outcome of RFCA. Methods: We analyzed 3D computed tomographic (CT) images of LA in 70 patients with AF (54 males, 55.6 ± 10.5 years old, paroxysmal AF (PAF):persistent AF (PeAF) = 32:38) who underwent RFCA. Each LA image was divided into venous atrium (VA), anterior LA (ALA), LA appendage (LAA), and both antrum. Absolute and relative volumes were calculated, and the lengths of linear ablation sites were measured. Results: (1) In patients with the mean LA voltage ≤ 2.0 mV, LA volume, especially ALA, was larger (P < 0.01) compared to those with LA voltage > 2.0 mV. (2) The total LA volume was significantly larger (P < 0.01) and LAA voltages (P < 0.05) and conduction velocities (P < 0.05) were lower in patients with PeAF than in those with PAF. (3) In patients with recurrence, LA volume was generally larger (P < 0.01) than in those without recurrence. In PAF patients with recurrence, the relative volume of ALA was significantly larger (P < 0.01) than those without recurrence. Conclusions Morphologically remodeled LA has low endocardial voltage, and enlargement of ALA is more significant in electroanatomically remodeled LA. The disproportional enlargement of ALA was observed more often in PAF patients with recurrence after ablation than those without recurrence. 相似文献
39.
Dover AR Chia S Ferguson JW Cruden NL Megson IL Fox KA Newby DE 《Clinical science (London, England : 1979)》2006,111(4):275-280
Enhanced iNOS (inducible nitric oxide synthase) activity may contribute to vascular dysfunction in patients with heart failure. In the present study, we aimed to determine whether iNOS activity contributes to the maintenance of vascular tone in patients with symptomatic heart failure with the use of the highly selective iNOS inhibitor 1400W {N-[3-(aminomethyl)benzyl] acetamidine}. Bilateral forearm blood flow was measured using venous occlusion plethysmography in 12 patients with New York Heart Association class II-IV heart failure and eight matched healthy control subjects during intra-brachial infusion of 1400W (0.1-1 micromol/min), L-NMMA (N(G)-monomethyl-L-arginine; a non-selective NOS inhibitor; 2-8 micromol/min) and noradrenaline (control vasoconstrictor; 60-480 pmol/min). In both patients and controls, intra-brachial infusion of L-NMMA and noradrenaline caused a dose-dependent reduction in infused forearm blood flow (P<0.05 for both): peak reduction of 32+/-6% and 37+/-4% during L-NMMA and 52+/-6% and 49+/-5% during noradrenaline respectively (P values were not significant when patients were compared with controls). In contrast, 1400W had no effect on blood flow at 1 micromol/min [-3+/-4% in patients (95% confidence intervals, -11 to 5%) and 3+/-8% in controls; P value was not significant]. In conclusion, we have demonstrated that intrabrachial selective iNOS inhibition does not influence forearm blood flow in patients with heart failure. We conclude that iNOS activity does not contribute to peripheral vascular tone in patients with symptomatic heart failure. 相似文献
40.
HWAN‐CHEOL PARK M.D. SUNG IL CHOI M.D. JAE UNG LEE M.D. Ph.D. SOON‐GIL KIM M.D. Ph.D. JINHO SHIN M.D. Ph.D. HYUN‐JOONG KIM M.D. Ph.D. 《Journal of interventional cardiology》2013,26(5):491-500