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131.
Gynecomastia--pathogenesis, diagnosis and treatment 总被引:1,自引:0,他引:1
The aim of this review is to present the up-to-date information concerning the prevalence, pathogenesis, diagnosis and treatment of gynecomastia. Gynecomastia is a benign, unilateral or bilateral enlargement of the male breast due to the imbalance between the androgens and estrogens at the breast tissue level. This clinical condition is particularly common in boys during puberty and in aging men. The breast enlargement, especially with accompanying pain can cause serious psychological problem. At the present time there are no generally accepted procedures for the evaluation and treatment of patients with gynecomastia. In the article such recommendations were proposed. There are many studies conducted to find the safe and efficient medical therapy that could ameliorate the quality of life of the patients with gynecomastia. The information on the available treatment options were also presented. 相似文献
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133.
Prolidase [E.C. 3.4.13.9], a member of the matrix metalloproteinase (MMP) family, is a manganese-dependent cytosolic exopeptidase that cleaves imidodipeptides containing C-terminal proline or hydroxyproline. It plays an important role in collagen metabolism, matrix remodeling and cell growth. Nitric oxide (NO), a versatile signaling molecule, regulates many processes including collagen synthesis and matrix remodeling and, thereby, may modulate angiogenesis, tumor invasiveness, and metastasis. Thus, we considered that prolidase may be an important target of NO regulation. In our study, SIN I and DETA/NO were used as NO donors. Both donors increased prolidase activity in a time-dependent and dose-dependent manner. Prolidase activity increased not only with NO donors but also with endogenous NO in cells transfected with iNOS. The effect of iNOS was abolished by treatment with S-methylisothiourea (SMT), a selective inhibitor of iNOS. However, with either exogenous or endogenous sources of NO, the increase in prolidase activity was not accompanied by increased prolidase expression. Therefore, we suspected phosphorylation of prolidase as a potential mechanism regulating enzyme activation. We observed increased serine/threonine phosphorylation on prolidase protein in cells treated with NO donors and in cells transfected with iNOS. To determinate the pathways that may mediate prolidase induction by NO, we first used 8-Br-cGMP, a cGMP agonist, and found that 8-Br-cGMP strongly and rapidly stimulated prolidase activity accompanied by increased phosphorylation. Rp-8-Br-pCPT-cGMP, an inhibitor of cGMP, reduced NO donor-stimulated prolidase activity to control levels. To test whether the MAPK pathway is involved in this NO-dependent activation, we used an ERK1/2 inhibitor and found that it had no effect on prolidase activity increased by NO donors. These results demonstrate that NO stimulates prolidase activity by increasing serine/threonine phosphorylation through PKG-cGMP pathway, but independent of MAPK and suggest an interaction between inflammatory signaling pathways and regulation of the terminal step of matrix degradation. 相似文献
134.
Kordowiak AM Goc A Drozdowska E Turyna B Dabros W 《Journal of inorganic biochemistry》2005,99(5):1083-1089
The paper presents the effect of one-week 3mM sodium orthovanadate (Na3VO4) oral treatment of control and streptozotocin[STZ]-diabetic rats. The body weight decreased as compared with untreated control (C group) in both vanadate treated groups (C + V and D + V) and in diabetic untreated rats (D group)--in all cases p < 0.01. A similar tendency was demonstrated by the weight of the livers, which was statistically significant lower than in the controls (p < 0.01). The fluid and food intake were lower in comparison with control vanadium treated groups, in D + V as compared with D it was limited, however, not achieved control level. A high mortality rate, approx. 67%, after the administration of streptozotocin and vanadate (D + V group) was noted; such result had never been previously found within all study groups of rats. But the surviving rats show very good decreased (60%) free blood sugar levels, however euglycaemia was not achieved. The activity of galactosyltransferase, the Golgi complex marker enzyme in group D, was statistically lower than the controls (p < 0.001). Treatment of STZ-diabetic rats with orthovanadate did not increase the enzyme activity toward control level, in both diabetic groups (treated and untreated with Na3VO4) similar dispersion of individual results was found. Morphological study demonstrated, for the first time, no larger cellular lesion in C + V group. The Golgi complex was well developed; showed several cisterns at the trans side, which were grossly distended and contained electron-lucid floccular material. In D + V group typical, cylindrical forms of Golgi complexes predominated. These structures consisted of 3-4 almost practically non-distended cisterns. Also in this case, large, electron-dense vesicles were noted in the vicinity. In this group, small in size, myelin-like structures were also found. These structures might indicate a relatively small, but nevertheless clear damage of the internal membrane system. The external cistern of the cylindrical forms of Golgi complexes, which corresponded the trans side, was often markedly distended and formed a vacuole-like structure filled with electron lucent material; the structure itself sometimes looked empty. Multi-vesicular structures were observed also in this case, but they were seen much more rarely. 相似文献
135.
Martin BA Kalata W Loth F Royston TJ Oshinski JN 《Journal of biomechanical engineering》2005,127(7):1110-1120
A simplified in vitro model of the spinal canal, based on in vivo magnetic resonance imaging, was used to examine the hydrodynamics of the human spinal cord and subarachnoid space with syringomyelia. In vivo magnetic resonance imaging (MRI) measurements of subarachnoid (SAS) geometry and cerebrospinal fluid velocity were acquired in a patient with syringomyelia and used to aid in the in vitro model design and experiment. The in vitro model contained a fluid-filled coaxial elastic tube to represent a syrinx. A computer controlled pulsatile pump was used to subject the in vitro model to a CSF flow waveform representative of that measured in vivo. Fluid velocity was measured at three axial locations within the in vitro model using the same MRI scanner as the patient study. Pressure and syrinx wall motion measurements were conducted external to the MR scanner using the same model and flow input. Transducers measured unsteady pressure both in the SAS and intra-syrinx at four axial locations in the model A laser Doppler vibrometer recorded the syrinx wall motion at 18 axial locations and three polar positions. Results indicated that the peak-to-peak amplitude of the SAS flow waveform in vivo was approximately tenfold that of the syrinx and in phase (SAS approximately 5.2 +/- 0.6 ml/s, syrinx approximately 0.5 +/- 0.3 ml/s). The in vitro flow waveform approximated the in vivo peak-to-peak magnitude (SAS approximately 4.6 +/- 0.2 ml/s, syrinx approximately 0.4 +/- 0.3 ml/s). Peak-to-peak in vitro pressure variation in both the SAS and syrinx was approximately 6 mm Hg. Syrinx pressure waveform lead the SAS pressure waveform by approximately 40 ms. Syrinx pressure was found to be less than the SAS for approximately 200 ms during the 860-ms flow cycle. Unsteady pulse wave velocity in the syrinx was computed to be a maximum of approximately 25 m/s. LDV measurements indicated that spinal cord wall motion was nonaxisymmetric with a maximum displacement of approximately 140 microm, which is below the resolution limit of MRI. Agreement between in vivo and in vitro MR measurements demonstrates that the hydrodynamics in the fluid filled coaxial elastic tube system are similar to those present in a single patient with syringomyelia. The presented in vitro study of spinal cord wall motion, and complex unsteady pressure and flow environment within the syrinx and SAS, provides insight into the complex biomechanical forces present in syringomyelia. 相似文献
136.
Zachara BA Szewczyk-Golec K Wolski Z Tyloch J Skok Z Bloch-Boguslawska E Wasowicz W 《Biological trace element research》2005,103(3):199-206
The dietary microelement selenium (Se) has been proposed as a potential chemopreventive agent for prostate cancer. This element
is present in various amounts in all tissues. Little information is available on Se level in patients with prostate gland
disorders. The levels of Se in prostatic gland of patients with prostate cancer, benign prostate hyperplasia, and healthy
controls were examined. The Se level for benign prostate hyperplasia (156±30.6 ng/g) was the same as in the control group
(157±26.0 ng/g), but in the gland of prostate cancer patients (182±34.1 ng/g wet weight), the Se level was significantly (p<0.01) higher than in both healthy controls and benign prostate hyperplasia. Thus, the Se level in human healthy controls
is lower than in kidney and liver but higher compared with other tissues. 相似文献
137.
Impaired antioxidant mechanisms are unable to inactivate free radicals that may induce a number of pathophysiological processes and result in cell injury. Thus, any abnormality in antioxidant defense systems could affect neurodevelopmental processes and could have an important role in the etiology of cerebral palsy (CP). The plasma levels of lipid peroxidation as plasma levels of malondialdehyde (MDA), activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) in plasma and erythrocytes were investigated in 34 CP children and compared with 61 normal controls. SOD, GPx and GR activities were spectrophotometrically assayed. Activities of SOD, GPx and GR in plasma did not differ significantly between CP children and the control group. Activities of erythrocyte GR in the CP patients were significantly lower compared with controls. MDA concentration did not differ statistically between the CP children and healthy subjects. In conclusion our results suggest that increased activities of erythrocyte GPx and decreased erythrocyte GR activities might be due to lesser physical activity of children with CP. 相似文献
138.
Srebniak M Popowska L Wawrzkiewicz-Witkowska A Tomaszewska A Kazmierczak W 《Journal of applied genetics》2005,46(3):333-336
A couple was referred for cytogenetic examination due to idiopathic miscarriages. The proband proved to be a carrier of chromosomal translocation and her partner's karyotype was found to be normal. The karyotype of the proband is 46,XX,t(4;22)(q23;q11.2) and can be regarded as a reason of fertility problems in the investigated couple. The risk of further miscarriages is high, but the risk of a progeny with abnormal karyotype is rather low, as the progeny would probably have lethal imbalances. 相似文献
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140.