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1.
Human interleukin 3 (IL-3) is a multipotential cytokine that supports the growth of early hematopoietic progenitors and promotes their response to other, later-acting cytokines. We found that IL-3 was able to induce the expression of interleukin 2 (IL-2) receptor (IL-2R) (CD25) on a subset of early myeloid cells in normal human bone marrow that had been first depleted of mature hematopoietic cells and E-rosette-positive T cells by treatment with soybean lectin and sheep erythrocytes (SBA-E-BM). Immunofluorescence analysis revealed that the CD25+ cells were contained almost entirely within the lymphoblastoid gate of the IL-3-cultured marrow. CD25 was undetectable on freshly isolated marrow and less than 10% CD25+ cells could be detected following liquid culture at 37 degrees C in the presence of 10% human serum, 10% fetal calf serum, or under serum-free conditions. Addition of IL-3 (100 U/ml) significantly increased the expression of CD25 to 37%, 31%, and 24%, respectively. CD25 could also be induced by granulocyte-macrophage colony-stimulating factor (GM-CSF), but no IL-2R was detectable following exposure to granulocyte colony-stimulating factor (G-CSF), macrophage colony-stimulating factor (M-CSF), interleukin 1 (IL-1), interleukin 4 (IL-4), or IL-2. Expression of CD25 was dependent on the dose of IL-3 or GM-CSF added and was maximal within 24 h of exposure. Two-color immunofluorescence analysis demonstrated that CD25 was not expressed by cells of lymphoid lineage or by mature monocytes, but rather was present on cells that coexpressed CD13, CD33, CD34, MY8, and HLA-DR, and that lacked CD14 or CD11b, thus placing the CD25+ cells at or near the myeloblast stage of differentiation. An identical phenotype was found for CD25+ cells induced by GM-CSF. Cycloheximide completely inhibited the IL-3-induced expression of CD25, indicating the necessity for protein synthesis, and although most of the CD25+ cells were in G0/G1 phase, 25% of the cells were in S or G2M phase, indicating that receptor expression was not cell-cycle dependent. The p75 chain of IL-2R was not detected on the CD25+ cells. IL-3 was also found to directly induce CD25 in greater than 46% of SBA-E-BM enriched for CD34+ cells by panning. Consistent with the expression of only p55 IL-2R, the functional activity of IL-2 on enriched CD34+ cells exposed to IL-3 could not be demonstrated in either granulocyte-macrophage colony-forming unit (CFU-GM) assays or proliferation assays.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
2.
Glial-derived neurotrophic factor (GDNF), neurturin (NRTN), persephin (PSPN), and artemin (ARTN) are a group of proteins belonging to the GDNF family ligands (GFLs). GDNF, NRTN, and ARTN support the survival of central, peripheral, and autonomic neuron populations, while PSPN supports the survival of only several central neuron populations. A common receptor, RET, modulates the action of this family and a co-receptor, GFRα, determines RET ligand specificity. GDNF and NRTN appear to be essential for enteric nervous system (ENS) development in mammals, zebrafish, and other teleostean species. GFLs are also essential for the maintenance and plasticity of adult mammalian ENS. In this study, the distribution pattern of GFLs in the intestine of five adult fish (bass, gilt-head, scorpionfish, trout, and zebrafish) was evaluated by immunochemical and immunocytochemical analysis. The results demonstrated the presence of GDNF, NRTN, and ARTN in the gut of all species studied. They appeared to be spread in the ENS and/or endocrine cells of the intestine. These findings suggest that the presence of GFLs in fish gut is not only limited to developmental period, but could be also involved in the enteric physiology of adult species.  相似文献   
3.
Physical activity increases the work load of the heart. The adjustments of the heart depend on the quality and quantity of the work performed. These adjustments concern the function and the morphology of the cardiovascular system. It is important to underline that these adjustments are not permanent and can disappear when physical activity is stopped. In young subjects the risks are very few while the benefits may be shown on a better and more armonic body structure. In the elderly the benefits can be achieved with a lesser cost for submaximal activities, but the risks are of course more frequent due the possible onset of cardiovascular disease. It is important to correctly recognize the limits whitin which the physical activity can be allowed because beneficial. Echocardiography has given an important contribution to evaluate the morpho-functional adaptions of the athlete's heart. Similarly, it has proven useful in the detection of pathological cardiovascular modifications, asymptomatic or pausymptomatic, that do not allow certification to practise sport at agonistic levels.  相似文献   
4.
To evaluate the safety and efficacy of Chinese medicine, Qiaoshao formula combined with dapoxetine was used for the treatment of premature ejaculation in a real-life setting. Nine hundred and five males diagnosed with premature ejaculation were reviewed in this retrospective cohort study. We divided the patients into two groups: dapoxetine alone and Qiaoshao formula combined with dapoxetine according to actual interventions provided to patients in clinics. The perceived intravaginal ejaculation latency time and the premature ejaculation profile measures markedly improved in both groups. However, in men with severe premature ejaculation (baseline perceived intravaginal ejaculation latency time <1 min) and those with baseline age ≤30 years, the perceived intravaginal ejaculation latency time was slightly but significantly longer with combined therapy than with dapoxetine alone (p < .05). Therefore, combined therapy involving the Qiaoshao formula and dapoxetine proved to safe as well as effective for treating premature ejaculation while prolonging the perceived intravaginal ejaculation latency time, which significantly improved the overall satisfaction of the patient and likely that of the couple.  相似文献   
5.
IntroductionThere is general agreement that it is possible to have an orgasm thru the direct simulation of the external clitoris. In contrast, the possibility of achieving climax during penetration has been controversial.MethodsSix scientists with different experimental evidence debate the existence of the vaginally activated orgasm (VAO).Main Outcome MeasureTo give reader of The Journal of Sexual Medicine sufficient data to form her/his own opinion on an important topic of female sexuality.ResultsExpert #1, the Controversy's section Editor, together with Expert #2, reviewed data from the literature demonstrating the anatomical possibility for the VAO. Expert #3 presents validating women's reports of pleasurable sexual responses and adaptive significance of the VAO. Echographic dynamic evidence induced Expert # 4 to describe one single orgasm, obtained from stimulation of either the external or internal clitoris, during penetration. Expert #5 reviewed his elegant experiments showing the uniquely different sensory responses to clitoral, vaginal, and cervical stimulation. Finally, the last Expert presented findings on the psychological scenario behind VAO.ConclusionThe assumption that women may experience only the clitoral, external orgasm is not based on the best available scientific evidence. Jannini EA, Rubio‐Casillas A, Whipple B, Buisson O, Komisaruk BR, and Brody S. Female orgasm(s): one, two, several. J Sex Med 2012;9:956–965.  相似文献   
6.
Background Polycystic ovary syndrome (PCOS) is a common female reproductive‐age endocrine disease predominantly characterized by chronic anovulation, hyperandrogenism, insulin‐resistance and low‐grade inflammatory status. Exercise training (ET) favourably modulates cardiopulmonary function and insulin‐sensitivity markers in PCOS women. The present study investigated the effects of ET on autonomic function and inflammatory pattern in PCOS women. Study design Prospective baseline uncontrolled clinical study. Methods One‐hundred and eighty five PCOS women referred to our department were screened for the inclusion into the study protocol from March 2004 to July 2007. One‐hundred and twenty four PCOS women met the criteria for the inclusion into the study protocol and were subdivided into two groups each composed of 62 patients: PCOS‐T (trained) group underwent 3‐month ET program, whereas PCOS‐UnT (untrained) group did not. At baseline and at 3‐month follow‐up, hormonal and metabolic profile, cardiopulmonary parameters, autonomic function (as expressed by heart rate recovery, HRR) and inflammatory pattern [as expressed by C‐reactive protein (CRP) and white blood cells (WBCs) count] were evaluated. Results PCOS‐T showed a significant (P < 0·05) improvement in maximal oxygen consumption (VO2max) and in post‐exercise HRR, and a significant (P < 0·001) decrease in CRP and WBCs; whereas no statistically significant changes of the same parameters were observed in PCOS‐UnT. Multiple linear regression analysis showed that 3‐month HRR is linearly related to the inclusion in training group (β = 0·316, P < 0·001), VO2max (β = 0·151, P = 0·032) and the ratio between glucose and insulin area under curve (AUC) (β = 0·207, P = 0·003), and inversely related to body mass index (β = –0·146, P = 0·046), insulin AUC (β = –0·152, P = 0·032), CRP (β = –0·165, P < 0·021), and WBCs count (β = –0·175, P = 0·039). Conclusions Exercise training improves autonomic function and inflammatory pattern in PCOS women.  相似文献   
7.
8.
Objective The aim of the present study was to determine if the favourable cardiopulmonary and metabolic benefits induced by exercise training (ET) programme are maintained after its cessation. Patients Thirty‐two young overweight polycystic ovary syndrome (PCOS) women matched for age and body mass index (BMI) with other 32 PCOS patients was enrolled. The first group [PCOS‐T (trained)] underwent 24‐week ET programme, whereas the second [PCOS‐DT (detrained)] underwent 12‐week ET programme followed by 12‐week detraining period. Methods At baseline, after 12‐ and 24‐week follow‐up, all PCOS women were studied for their hormonal (ovarian and adrenal androgens), metabolic (glucose and insulin) and lipid profile, and underwent cardiopulmonary exercise test. Results After the initial 12‐week ET programme, both PCOS‐T and PCOS‐DT groups, without differences between groups, showed a similar significant (P < 0·05) improvement in BMI, fasting insulin, areas under curve insulin (AUCINS), glucose and insulin AUC (AUCGLU/INS), high‐density lipoprotein‐cholesterol (HDL‐C), low‐density lipoprotein‐cholesterol (LDL‐C) and maximal oxygen consumption at cardiopulmonary exercise test (VO2max). At 24‐week follow‐up, PCOS‐T group showed a significant (P < 0·05) improvement in BMI, fasting insulin, AUCINS, AUCGLU/INS, LDL‐C, HDL‐C and VO2max, in comparison to baseline and 12‐week follow‐up. At same follow‐up visit, the all parameters resulted significantly (P < 0·05) worsened in PCOS‐DT group in comparison to 12‐week follow‐up and PCOS‐T group. In PCOS‐DT group, no parameter assessed at 24‐week follow‐up was significantly different in comparison with baseline. Conclusion In young PCOS women, 12‐week detraining resulted in a complete loss of the favourable adaptations obtained after ET.  相似文献   
9.
We assessed the functional properties and the kinetic status in vitro, and the engraftment potential in vivo of human haematopoietic stem cells according to the expression of CD34 antigen. Lin-CD34- and Lin-CD34+ cells were isolated from granulocyte colony-stimulating factor-primed peripheral blood (PB) cells of healthy donors. The CD34- cell fraction did not contain either clonogenic cells in semisolid culture or long-term culture initiating cells (LTC-IC). However, stroma-dependent liquid cultures and cytokines induced CD34 expression on a minority of stem cells, acquisition of clonogenic capacity and generation of LTC-IC. Significantly higher percentages of quiescent G0 cells and lower percentages of cycling G1 cells were found in Lin-CD34- cells when compared with Lin-CD34+ cells. Kinetic quiescence of Lin-CD34- cells was associated with a significantly higher expression of the negative regulators of the cell cycle, p27Kip1 and p21(cip1/waf1). Cytokine-mediated induction of CD34, in vitro, resulted in cycling of stem cells and downregulation of p27. There was a higher rate of human long-term engraftment in immunocompromised non-obese diabetic (NOD)/recombination activating gene 1null and NOD/severe combined immunodeficient-beta2microglobulin(null) mice injected with CD34+ cells. Thus, our study indicated that CD34 expression on human PB stem cells was associated with haematopoietic activity, cell-cycle recruitment and downregulation of p27Kip1 in vitro and higher engraftment capacity in vivo.  相似文献   
10.

Background

(Buccalin ®) is a Bacterial Lysates (BL) that belongs to a family of immune-stimulators, developed more than 30 years ago and it still has a role in the prophylaxis of Recurrent Respiratory Tract Infections (RRTI). However, original studies were conducted with an approach that does not seem to be aligned with the present methodologies. In addition, concomitant therapies substantially improved in the last decades. These two reasons strongly suggested to update our knowledge on the capacity of this bacterial lysate (Buccalin ®) to reduce the number of days with infectious episodes in patients with RRTI.

Methods

A double blind, placebo-controlled, randomized, multicentre study was programmed (EudraCT code: 2011-005187-25). The reduction of the number of days with infectious episodes (IE) was the primary endpoint. Secondary endpoints were the number of IE, the use of concomitant drugs, the efficacy on signs and symptoms of RRTI and the safety of the drug. Patients were treated according to the registered schedule and were followed up for a period of 6 months.

Results

From a cohort of 188 patients eligible for the study, 90 were included in the active group and 88 in the placebo group. The study was completed in 170 patients. A significant reduction of the number of days with IE was observed (6.57 days in the active group and 7.47 in the placebo group). Secondary endpoints were only partially achieved. No virtual adverse events related to the treatment were recorded.

Conclusion

The administration of bacterial lysate (Buccalin ®) in patients with RRTI had the capacity to significantly reduce the number of days with IE in a multicentre, randomized, placebo controlled, clinical study. The treatment was safe. Of note, all patients were free to be treated with the best concomitant therapies. In these conditions, the positive results observed demonstrated that this bacterial lysate has maintained its capacity of reducing the days with infections in patients with RRTI, also in association to the concomitant therapies available nowadays.
  相似文献   
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