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The present study aimed to evaluate the late-term changes in radial artery luminal diameter (RAD) and vasodilatation response following transradial catheterization (TRC). TRC-inducing trauma to radial artery intima may trigger chronic phase vascular changes and lead to anatomical and functional impairment. There is controversial data whether the impairment persists or repairs later. Fifty-six consecutive patients undergoing TRC were enrolled prospectively. Baseline RAD, flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) of the radial artery at the access site were measured before TRC by high-resolution ultrasound. Six months later; RAD, FMD and NMD were measured again at the same access site. RAD at the sixth month was reduced compared with pre-procedural measurements (2.85 ± 0.44 versus 2.74 ± 0.42 mm, p = 0.0001).The average FMD decreased to 5.66 ± 5.87 %, which was significantly lower than the observed pre-procedural FMD (9.45 ± 5.01 %) 6 months after TRC (p = 0.0001). Likewise, the average NMD at the sixth month was reduced compared with pre-procedural NMD (9.52 ± 6.77 versus 6.64 ± 6.51 %, p = 0.018). Logistic regression analysis indicated that pre-procedural radial artery diameter to sheath size ratio was the independent predictor of NMD reduction (95 % confidence interval, β = ?9.74, p = 0.024). TRC may lead to a significant luminal diameter reduction and impairment of vasodilatation response in the radial artery at late term.  相似文献   
74.
Human Mast Cell Apoptosis Is Regulated Through Bcl-2 and Bcl-XL   总被引:4,自引:0,他引:4  
It is well established that human mast cell proliferation and maturation are regulated by kit ligand (stem cell factor). Little is known, however, about how these two processes are negatively regulated and thus, how mast cell number is controlled in normal and pathologic conditions. We therefore first hypothesized that SCF-dependent human mast cells would undergo programmed cell death (apoptosis) on removal of SCF as has been shown for growth factor-dependent rodent mast cells. We then examined whether SCF acts as a survival factor through the regulation of the bcl-2 family of apoptosis-regulatory genes. As hypothesized, elimination of SCF from primary peripheral blood-derived human mast cell cultures resulted in a significant apoptotic process. During apoptosis, down-regulation of the two apoptosis-regulatory proteins Bcl-2 and Bcl-XLwas observed. Moreover, a deregulated expression of these two proteins was found in two human mast cell lines which are SCF-independent. Thus, SCF functions as a survival factor by repressing apoptosis of human mast cells through Bcl-2 and Bcl-XL. Deregulated expression of these antiapoptotic proteins may contribute to proliferation and accumulation of mast cells in certain forms of systemic mast cell disorders.  相似文献   
75.
Migraine attacks are characterized by headaches associated with neurological, gastrointestinal, and autonomic symptoms. A relationship between migraine and hypertension or hypotension is controversial. In this study, we aimed to determine if blood pressure changes were related to migraine attacks. From the outpatient clinic of our neurology department, 62 normotensive migraine patients with and without aura were chosen for study in accordance with the International Headache Society 2004 criteria. A questionnaire including general and specific questions was given to the patients to be filled out during 6 consequent migraine attacks. The patients received a fully automatic digital brachial upper arm sphygmomanometer (Omron M 4‐1) to measure the changes in their blood pressure during attacks. The patients were asked to record their blood pressure changes 3 times: (1) just before or very early, (2) during (when headache peaks), and (3) 1 hour after the attack. Twenty‐three of the 62 patients (57 women, 5 men) had migraine with aura (22 women and 1 man), and 39 of them did not have aura (35 women and 4 men). There was no statistically significant difference between systolic and diastolic values obtained before or very early, during the peak level, and 1 hour after the end of the attacks (P > 0.05). Although diastolic hypotensive values were not different statistically between groups, when all the patients were considered, diastolic hypotensive values were detected in a considerable number of patients (a total of 115 measurements). In this normotensive migrainous population, we observed that diastolic hypotension before or very early, during, and after migraine attack was the most significant result (5.1%). Although it was not statistically significant, the total number of hypotensive values was remarkable.  相似文献   
76.
The aim of the present study was to compare follicular fluid (FF) levels of norepinephrine (NE) and dopamine (DA) in polycystic ovary syndrome (PCOS) and non-PCOS patients who underwent in vitro fertilization (IVF). Forty-seven PCOS patients (study group) and 61 patients with male factor infertility (control group) who underwent IVF using GnRH agonist protocol were recruited. Concentrations of NE and DA were measured in FF specimens of all patients. Demographic characteristics were comparable between the groups. Significantly higher levels of NE were measured in FF of PCOS patients (median: 61.05?nmol/l) compared to those with male infertility (median: 49.82?nmol/l). Similarly, significantly higher levels of DA were measured in FF of PCOS patients (median: 23.70?nmol/l) compared to those with male infertility (median: 18.28?nmol/l). In conclusion, the FF concentrations of both catecholamine are increased in PCOS patients when compared to non-PCOS patients.  相似文献   
77.
A survey study was conducted to investigate the possible effects of mobile phone on headache, dizziness, extreme irritation, shaking in the hands, speaking falteringly, forgetfulness, neuro-psychological discomfort, increase in the carelessness, decrease of the reflex and clicking sound in the ears. There is no effect on dizziness, shaking in hands, speaking falteringly and neuro-psychological discomfort, but some statistical evidences are found that mobile phone may cause headache, extreme irritation, increase in the carelessness, forgetfulness, decrease of the reflex and clicking sound in the ears.  相似文献   
78.
We investigated the cytoprotective effect of melatonin in epirubicin-induced cardiotoxicity using four experimental groups of male Wistar rats: untreated control rats, epirubicin-treated rats, epirubicin+melatonin-treated rats, and melatonin-treated rats. We examined the histopathological and biochemical effects of melatonin on the epirubicin-induced changes and measured the levels of the lipid peroxidation end-product (malondialdehyde, MDA), an indicator of nitric oxide (NO) synthesis (nitrite/nitrate production), and reduced glutathione (GSH) in the heart. We also studied the extracellular matrix components (fibronectin, laminin) in the heart. Vacuole formation, mitochondrial deformation and degeneration, and disordered myofibrillary structures were detected ultrastructurally in the epirubicin-treated group. The degeneration was reduced in the heart tissues of the epirubicin+melatonin group. Epirubicin increased the nitrite/nitrate production, but did not change the MDA and GSH levels significantly. Melatonin treatment lowered the nitrite/nitrate concentrations, while increasing the GSH levels, which exceeded the levels in epirubicin+melatonin-treated rats. We conclude that the epirubicin increased the nitrozative stress, not the oxidative stress, in heart tissue, and the cardioprotective effect of melatonin was partially attributed to the suppression of epirubicin-induced nitrozative stress. These results suggest that melatonin partially protects against epirubicin-induced cardiotoxicity.  相似文献   
79.
IL-1, IL-18, and IL-33 families of cytokines   总被引:4,自引:0,他引:4  
Summary: The interleukin-1 (IL-1), IL-18, and IL-33 families of cytokines are related by mechanism of origin, receptor structure, and signal transduction pathways utilized. All three cytokines are synthesized as precursor molecules and cleaved by the enzyme caspase-1 before or during release from the cell. The NALP-3 inflammasome is of crucial importance in generating active caspase-1. The IL-1 family contains two agonists, IL-1α and IL-1β, a specific inhibitor, IL-1 receptor antagonist (IL-1Ra), and two receptors, the biologically active type IL-1R and inactive type II IL-1R. Both IL-1RI and IL-33R utilize the same interacting accessory protein (IL-1RAcP). The balance between IL-1 and IL-1Ra is important in preventing disease in various organs, and excess production of IL-1 has been implicated in many human diseases. The IL-18 family also contains a specific inhibitor, the IL-18-binding protein (IL-18BP), which binds IL-18 in the fluid phase. The IL-18 receptor is similar to the IL-1 receptor complex, including a single ligand-binding chain and a different interacting accessory protein. IL-18 provides an important link between the innate and adaptive immune responses. Newly described IL-33 binds to the orphan IL-1 family receptor T1/ST2 and stimulates T-helper 2 responses as well as mast cells.  相似文献   
80.
Background/aim Hepatitis B virus (HBV) vaccination rates are insufficient in high-risk patients worldwide. This study aimed to investigate the screening, immunization, and vaccination rates in three high-risk groups for HBV infection: allogeneic hematopoietic stem cell transplantation (AHSCT), renal transplantation (RT), and chronic hepatitis C (CHC) groups. Materials and methods The serological data of consecutive patients between 2014 and 2019 were reviewed using the hospital database. Results The HBV screening rates were 100.0%, 90.4%, and 82.4% in the AHSCT, CHC, and RT groups, respectively (p = 0.003). The immunization rates against HBV through either previous exposure or vaccination were 79.5%, 71.7%, and 46.5% in the AHSCT, RT, and CHC groups, respectively (p < 0.001). The HBV vaccination rate was significantly low in the CHC group (71.5%, 69.0%, 34.6% in the AHSCT, RT, and CHC groups, respectively, p < 0.001). If patients lost their immunity due to immunosuppressive therapy were accounted, the vaccination rates increased to 95.2% in the AHSCT group and 72.9% in the RT group. The rate of annual screening for HBV status was 97.9% in the AHSCT group, but it was only 23.9% in the RT group. Conclusion HBV screening and vaccination rates were significantly lower in the RT and CHC groups than in the AHSCT group.  相似文献   
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