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41.
42.

Background

Endothelial progenitor cells (EPC) which are characterised by the simulateous expression of CD34, CD133 and vascular endothelial growth receptor 2 (VEGF 2) are involved in the pathophysiology of congestive heart failure (CHF) and their number and function is reduced in CHF. But so far our knowledge about the number of circulating hematopoietic stem/progenitor cells (CPC) expressing the early hematopoietic marker CD133 and CD34 in CHF is spares and therefore we determined their number and correlated them with New York Heart Association (NYHA) functional class.

Methods

CD34 and CD133 surface expression was quantified by flow cytometry in the peripheral venous blood of 41 healthy adults and 101 patients with various degrees of CHF.

Results

CD34+, CD133+ and CD34+/CD133+ cells correlated inversely with age. Both the number of CD34+ and of CD34+/CD133+ cells inversely correlated with NYHA functional class. The number of CD133+ cells was not affected by NYHA class. Furthermore the number of CD133+ cells did not differ between control and CHF patients.

Conclusion

In CHF the release of CD34+, CD133+ and CD34+/CD133+ cells from the bone marrow seems to be regulated differently. Modulating the releasing process in CHF may be a tool in CHF treatment.  相似文献   
43.

Background and Objective:

We conducted this study to evaluate and compare postpartum sexual functioning after vaginal and caesarean births.

Materials and Methods:

This was a cross-sectional study that was carried out in postnatal health care in a hospital. A total of 50 primiprous women who had given birth 6-12 months ago and came to the hospital for postnatal care were asked to join the study. Forty of the women completed the entire questionnaire. Among these women, 20 delivered spontaneously with mediolateral episiotomy and 20 had elective caesarean section. Sexual function was evaluated by a validated, self-created questionnaire. A statistical evaluation was carried out by SPSS v.11. A two-part self-created validated questionnaire for data collection was administered regarding sexual function prior to pregnancy and 6-12 months postpartum.

Results:

The median time to restart intercourse in the normal vaginal delivery with episiotomy (NVD/epi) group was 40 days and in the caesarean section (C/S) group was 10 days postpartum. The most common problems in the NVD/epi group was decreased libido (80%), sexual dissatisfaction (65%), and vaginal looseness (55%). In the C/S group, the most common problems were vaginal dryness (85%), sexual dissatisfaction (60%), and decreased libido (35%). There were clinically significant differences between the two groups regarding sexual outcomes, but these differences were not statically significant.

Conclusion:

Postnatal sexual problems were very common after both NVD/epi and C/S. Because sexual problems are so prevalent during the postpartum period, clinicians should draw more attention to the women''s sexual life and try to improve their quality of life after delivery.  相似文献   
44.
Epidemiologic and preclinical studies suggest that cyclooxygenase-2 (Cox-2) may promote tumor growth and spread by affecting angiogenesis and apoptosis in breast cancer. Using a tissue microarray (TMA), we analyzed the expression and subcellular localization of Cox-2 by AQUA and X-tile, our algorithms for quantitative analysis of protein expression and determination of optimal cutpoints. Our TMA consisted of 669 Stage I-III primary breast cancers. The total tumor and subcellular expression of Cox-2 were then correlated with clinicopathologic factors and with survival. Cox-2 expression appeared higher in malignant than in benign tissue and was predominantly membrane/cytoplasmic (i.e. non-nuclear). X-tile determines an optimum cutpoint on a training set then uses this cutpoint on a validation set. This cutpoint was 19.3 (top 44 percent defined as positive) with high nonnuclear Cox-2 expressers having significantly worse survival. Cox-2 expression also was inversely associated with estrogen receptor (ER) and progesterone receptor (PR), and directly associated with nuclear grade. Multivariate analysis showed that Cox-2 remained a significant prognostic factor for survival independent of tumor size, nodal status, ER, Her2/neu, and grade. In summary, Cox-2 is overexpressed in breast neoplasms, is associated with other markers of poor prognosis, and is significantly associated with worse survival independent of known prognostic factors. Furthermore, AQUA and X-tile analysis suggest an optimal cutpoint that may be helpful in future investigations of Cox-2 and specifically, in studies looking at its expression as a predictive biomarker in clinical trials of Cox-2 inhibitors in breast cancer.  相似文献   
45.
Magnetic resonance angiography   总被引:6,自引:0,他引:6  
Dumoulin  CL; Hart  HR  Jr 《Radiology》1986,161(3):717-720
Pulse sequences that permit selective detection of moving spins in a magnetic resonance image have been developed. Experiments were performed by the authors to produce projected angiographic data without the use of contrast agents, with the intensity of each image pixel determined by the macroscopic velocity of the detected spins. With this method, suppression of nonmoving spins is essentially complete, yielding a high dynamic range in signal intensity for detected vessels. Selective detection of moving spins is not dependent on pulsatile flow. Consequently, not only arterial structures, but also venous structures can easily be visualized. High-resolution angiographic images can be obtained by combining the flow experiment with surface coil techniques.  相似文献   
46.
Abramson  JS; Hudnor  HR 《Blood》1994,83(7):1929-1934
Patients infected with influenza A virus (IAV) are at increased risk for bacterial superinfections, and this occurs in association with depressed polymorphonuclear leukocyte (PMNL) function. Recently, we reported that in vitro exposure of human PMNL to granulocyte-macrophage colony-stimulating factor (GM-CSF) reverses IAV-induced cell dysfunction. The present study used an established animal model of IAV infection to examine whether G-CSF and/or GM-CSF can overcome IAV- induced PMNL dysfunction and thereby prevent secondary infections. Preliminary studies determined a dosing schedule of these cytokines that caused significant priming of chinchilla PMNL. In subsequent studies, animals were inoculated intranasally with IAV (day 1) followed 3 days later by Streptococcus pneumoniae, and administered daily intraperitoneal injections with a cytokine or placebo on days 3 through 9. Animals had blood obtained on multiple occasions for PMNL studies, and were followed-up for evidence of pneumococcal disease. Both cytokines caused significant priming of the PMNL chemiluminescence response and this was associated with reversal of the IAV-induced PMNL dysfunction. However, neither cytokine decreased the incidence of pneumococcal disease.  相似文献   
47.
Hemodynamic unloading using the ventricular assist device [VAD] results in partial functional recovery of failing hearts that show increased susceptibility to cardiomyocyte apoptosis. The caspase cascade is the central element of the apoptotic process in cells. We therefore tested expression shifts of left ventricular mRNA of caspases and their endogenous inhibitors from 15 patients with VAD support and successful bridging to transplantation using semiquantitative RT-PCR. Cardiac unloading was shown by the reduction in ventricular Pro-ANP mRNA under VAD. No alteration of mRNA expression under VAD could be observed for initiator caspases, for their selective inhibitors or for apoptotic signal molecules from the mitochondrial intermembrane space. Only two unselective cardiac IAPs (inhibitor of apoptosis protein) were increased under VAD with better recovery in younger patients. In conclusion, our findings indicate that successful hemodynamic unloading by VAD support causes only minor, age-dependent recovery in the expression of IAPs, while presumed alterations in antiapoptotic modulator systems upstream of the caspase cascade still remain to be identified.  相似文献   
48.

Background

Due to the lack of a suitable and economic test for the analysis of the polymorphism at codon 167, we developed a new PCR-RFLP technique, based on a modified forward primer (UT-HC167 MF-primer), to identify simultaneously the SNPs at codons 167 and 200 of isotype 1 β-tubulin gene of Haemonchus contortus.

Methods

There already are several safe and easy methods for identification of point mutations at codons 198 and 200. Due to the lack of a reliable and easy method for the detection of the single nucleotide polymorphism (SNP) at codon 167, we developed an innovative PCR-RFLP technique based on a modified forward primer (UT-HC167 MF-primer), in which the nucleotide T at the position 443 was substituted through a nucleotide A creating a restriction site for restriction endonuclease SnaB I in the nucleotide sequences including codon 167. A total of 138 adult male H. contortus were collected from three different geo-climatic areas of Iran. The isolated genomic DNA of each single worm was amplified by PCR using primers flanking codon 167. The PCR product (527 bp) was then amplified by semi-nested PCR using the UT-HC167 MF-primer and the reverse primer achieving a PCR product of 451 bp in length. This PCR product was subsequently digested with the restriction endonucleases SnaB I and TaaI for analysis of the mutations at codons 167 and 200, respectively.

Results

All worms had two alleles encoding for phenylalanine (BZss homozygote) for both codons.

Conclusion

Using the UT-HC167 MF-primer and a suitable reverse primer designed upstream from codon 200, it is possible to amplify a PCR product which can be used for analysis of the SNPs at all three mentioned codons using RFLP.  相似文献   
49.
Cell markers in hairy cell leukemia studied in cells from 51 patients   总被引:3,自引:0,他引:3  
To determine the maturation arrest of the neoplastic cells of hairy- cell leukemia (HCL) and the spectrum of the surface markers on these cells, a series of 51 patients with this disease was studied. The cells of all but two of the patients showed monoclonal surface Ig with respect to light chains. In about one-third of the cases, only gamma heavy chain determinants were present on the cells; the majority carried multiple heavy chain determinants as documented by the application of different fluorochromes. Two patients each showed two different clones of cells, both of the same light chain type. In one of these two patients, two paraproteins were present in the serum. Intracytoplasmic Ig was found in only 4 of 39 cases, in all instances being IgM. All cases studied concerned cells with FclgG receptors; however, the density of this receptor varied. FcIgM receptors also showed a spectrum of density, with some cases showing very few FcIgM- positive cells. Receptors C3 were not observed on the hairy cells. Serum immunoglobulin levels were normal or increased. Paraproteins were found in the sera of 4 of 38 patients. These data suggest that HCL is a neoplasm of B lymphocytes. The neoplastic cells are probably arrested at a more mature stage than the cells of chronic lymphocytic leukemia. The multiple isotypes on the cells indicate a block at the "switch" phase from the small micro-carrying lymphocyte to the larger Ig- producing lymphocyte or plasma cell.  相似文献   
50.
Late conduction defects following aortic valve replacement   总被引:1,自引:0,他引:1  
BACKGROUND AND AIM OF THE STUDY: The study aim was to determine the incidence and clinical significance of late cardiac conduction defects (CD) after aortic valve replacement (AVR). METHODS: An analysis was made of 100 consecutive cases after AVR in a prospective outpatient evaluation program. RESULTS: The perioperative (30-day) mortality rate was 5%, and incidence of perioperative pacemaker implantation 3%. Among patients, 19% had CDs before surgery; a normal ECG was present during all periods in 45% of patients. The most frequent perioperative CD was left anterior hemiblock (LAHB; n = 8), and the most frequent late CD was left bundle branch block (LBBB; n = 8). Overall, 13.7% of operative survivors with normal preoperative and perioperative ECGs developed late CDs; one patient (1%) required pacemaker implantation 82 months after AVR. A further three patients (3%) had worsening of pre-existent CDs. Late CDs occurred over a wide time range (3 to 102 months) after surgery. CONCLUSION: There is an important incidence of CDs that occur late after AVR, even if the perioperative ECGs are normal; however, a need for late pacemaker implantation is rare. As CDs may occur at any time after surgery, regular follow up with precise evaluation of ECGs is called for.  相似文献   
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