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11.
Objective: To determine whether anionic ligands for the macrophage scavenger receptor inhibit the fertilization of mouse oocytes by mouse spermatozoa.

Design: In vitro study of sperm binding and two-cell embryo formation in the presence of scavenger receptor ligands. Sperm-oocyte interaction may be mediated by sulfated sugars. In this study, we tested other nonsulfated anionic ligands for the scavenger receptor for their ability to affect fertilization. The only common feature of these ligands is their anionic nature.

Setting: Oocytes and sperm from mice were used.

Main Outcome Measure(s): Binding of sperm to oocytes and subsequent formation of two cell embryos were determined.

Result(s): Fucoidin, polyinosinic acid, oxidized low-density lipoprotein, acetyl low-density lipoprotein, and malondialdehyde-modified LDL inhibited the binding and fertilization of mouse sperm to mouse oocytes. Addition of fresh sperm to oocytes previously treated with sperm in the presence of these agents restored the binding and fertilization.

Conclusion(s): These results show that charge-based interactions analogous to the interactions of the scavenger receptor with its ligands may play an important role in mammalian fertilization.  相似文献   

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In our search for new anticancer drugs, a series of binuclear ruthenium(III) thiosemicarbazone complexes of the type [RuCl2(EPh3)]2L (where E = P/As; L = binucleating monobasic tridentate thiosemicarbazone ligand) have been synthesized. Structural features were determined by various physico-chemical and spectral techniques. The interactions of these complexes with CT-DNA were investigated by absorption spectral study, indicates that the binuclear ruthenium(III) complexes form adducts with DNA and has intrinsic binding constant in the range of 1.0 × 104–7.9 × 104 M?1. The free radical scavenging activity of binuclear ruthenium(III) complexes have been determined by their interaction with the stable DPPH free radical. All the complexes exhibited significant antiproliferative activity against human breast cancer line, MCF-7. This research may provide knowledge that is an excellent backdrop for the rational design of promising drugs.  相似文献   
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The technique and early results of cusp-level chordal shortening for isolated anterior mitral leaflet prolapse in rheumatic mitral regurgitation were presented by us earlier. Here we present our experience from January 1989 through December 2000. Two hundred twenty-six patients underwent this procedure. The mean age was 18 +/- 7.22 years. Preoperatively, 38 (16.8%) patients were in New York Heart Association functional class 11, 160 (70.8%) were in class IIl, and 28 (12.4%) were in class IV. All patients underwent chordal shortening at the cusp level. In addition, 8 patients (3.5%) underwent chordal transfer, and 4 patients (1.8%) received neochordae. Two hundred twenty-one (97.8%) patients underwent posterior annuloplasty using a C-shaped polytetrafluoroethylene collar. In 85 (37.6%) patients, cuspal thinning was also performed. Early mortality was 3.5% (8 patients). Follow-up ranged from 1 to 144 months (mean, 53.02 +/- 31.10 months) and was 94% complete. In 68% of survivors, there was no or trivial mitral regurgitation. Ten patients required reoperation. There were 8 late deaths. Actuarial survival, mitral regurgitation-free survival, and event-free survival were 93.3% +/- 1.7%, 41.8% +/- 8.4%, and 73.6% +/- 6.6%, respectively. Among the 210 survivors, 159 (75.7%) were in New York Heart Association class I, 26 (12.4%) were in class II, 22 (10.5%) were in class III, and 3 (1.4%) were in class IV. We conclude that cusp-level chordal shortening for isolated anterior mitral leaflet prolapse is an effective procedure for correction of anterior mitral leaflet prolapse.  相似文献   
19.
BACKGROUND: The renewed interest in mitral valve replacement with a pulmonary autograft encouraged us to perform this procedure in selected patients. METHODS AND RESULTS: From August 2000 to February 2002, 10 patients between 30 and 52 years of age with calcific mitral valvular disease underwent the Ross II procedure. Patients were either in New York Heart Association functional class III (7/10) or IV (3/10). Transthoracic echocardiography was done in all the patients to confirm the diagnosis. A pulmonary autograft was used to replace the diseased mitral valve. Intraoperative transesophageal echocardiography confirmed normal functioning of the autograft. There were 2 early deaths. The 8 survivors are in New York Heart Association functional class I with excellent autograft and homograft function at a follow-up of 2-20 months (mean 9 months). CONCLUSIONS: This procedure is a viable option for mitral valve replacement in patients with calcific mitral valve disease. However, the procedure is technically demanding and requires a valve bank.  相似文献   
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Invasive fungal infections are a significant cause of morbidity and mortality among immunocompromised patients. Early and accurate identification of these pathogens is central to direct therapy and to improve overall outcome. PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) was evaluated as a novel means for identification of fungal pathogens. Using a database grounded by 60 ATCC reference strains, a total of 394 clinical fungal isolates (264 molds and 130 yeasts) were analyzed by PCR/ESI-MS; results were compared to phenotypic identification, and discrepant results were sequence confirmed. PCR/ESI-MS identified 81.4% of molds to either the genus or species level, with concordance rates of 89.7% and 87.4%, respectively, to phenotypic identification. Likewise, PCR/ESI-MS was able to identify 98.4% of yeasts to either the genus or species level, agreeing with 100% of phenotypic results at both the genus and species level. PCR/ESI-MS performed best with Aspergillus and Candida isolates, generating species-level identification in 94.4% and 99.2% of isolates, respectively. PCR/ESI-MS is a promising new technology for broad-range detection and identification of medically important fungal pathogens that cause invasive mycoses.  相似文献   
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