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31.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
32.
Rapid determination of trisomy 18 parental origin using fluorescent PCR and small tandem repeat markers: case reports 总被引:3,自引:0,他引:3
Ian Findlay Tamás Tóth Paul Matthews Tamás Marton Philip Quirke Zoltán Papp 《Clinical genetics》1998,53(2):92-95
Trisomy 18 is the second most common genetic defect after trisomy 21, almost 90% of which are due to additional chromosome from the mother. The parental origin of the additional chromosome can, if required, be determined by two methods: karyotyping, which takes several weeks; or, more recently, by polymerase chain reaction (PCR) which is often problematic. Fluorescent PCR of small tandem repeats (STRs) can determine the parental origin in the majority of cases within 5 h. Although the incidence of paternal origin is known for both trisomy 21 and trisomy 18, this technique can rapidly determine the parental origin in cases where there is insufficient samples to perform conventional tests. Determining parental origin by these methods may also have clinical significance in the diagnosis of chromosomal translocations or in the diagnosis of genetic disease using linkage analysis. 相似文献
33.
34.
Applications of magnetic resonance spectroscopy to diagnosis and monitoring of mitochondrial disease
Magnetic resonance spectroscopy (MRS) can now be performed on routine high-field clinical magnetic resonance imaging systems. Over the last decade it has provided several useful insights into the pathophysiology of mitochondrial disorders. More recently, the feasibility of applications to clinical diagnosis and monitoring have been demonstrated. Exciting new work suggests that carefully supervised physical conditioning in conjunction with sodium dichloroacetate administration can markedly enhance both biochemical measures of aerobic metabolism and functional performance of patients with mitochondrial myopathies.
Sommario La risonanza magnetica spettroscopica (MRS) può oggi essere effettuata di routine in apparecchi clinici di risonanza magnetica. Nell'ultima decade essa ha fornito importanti informazioni nella patofisiologia dei disordini mitocondriali. Più recentemente sono state dimostrate le sue possibilità di applicazione nella diagnosi clinica e nel monitoraggio di pazienti neurologici. Nuovi ed interessanti studi suggeriscono che un allenamento attentamente supervisionato in congiunzione con trattamento con dicloroacetato è capace di migliorare i parametri biochimici e la performance di pazienti con miopatie mitocondriali.相似文献
35.
During a 12-month period ending on November 30, 1988, data were collected on 2468 pediatric patients with wheezing who visited a pediatric ED. Cohort characteristics included: sex (64% male, 36% female), history of prematurity (12%), evidence of concurrent infection (82%), taking theophylline (35%), taking beta adrenergics (60%), taking cromolyn (6%), and taking corticosteroids (4%). The hospitalization rate was 10.5%. Seasonal variations, weather, air quality, and infections appeared to have significant effects on the daily variation of wheezing exacerbations. Initial oxygen saturation (OSAT) correlated with disease severity as measured by hospitalization risk and the number of bronchodilator treatments required in the ED. A suggestion for categorizing the treatment of asthma based on past history is proposed. Using this system in conjunction with pulse oximetry, wheezing severity and appropriate therapy can be more objectively determined. 相似文献
36.
Some patients present with distressing symptoms due to locally advanced prostatic carcinoma which may be refractory to hormonal manipulation and/or surgical treatment. Over an 8-year period 26 patients received local palliative radiotherapy for recurrent bleeding and lower urinary outflow tract obstruction. All were treated with conventional external beam radiotherapy and all but 2 obtained useful palliation of symptoms, especially those with recurrent bleeding. We also found that radiotherapy could be given to the majority of patients on an out-patient basis in 2 or 3 fractions. This was well tolerated and there were few side effects. 相似文献
37.
G. Pilkington S. Juneja L. Tan J. Matthews J. Quirk G. Lee P. Ironside I. Cooper D. Jose 《Hematological oncology》1993,11(4):195-205
The prognostic value of immunophenotyping lymphomas with a panel of monoclonal antibodies (Mab) to various lymphoid antigens was assessed by studying 47 cases of diffuse large cell lymphoma. Cell suspensions were analysed by flow cytometry after labelling by indirect immunofluorescence. Thirty-eight cases were demonstrated to be of B cell and nine of T cell phenotype. Univariate analysis demonstrated that survival was significantly longer in patients expressing higher levels of HLA-DR (p=0·01) and normal levels of CD8 (p=0·04) but was not significantly associated with any of the other antigens. Our results support the possible value of HLA-DR in determining the prognosis of patients with diffuse large cell lymphoma. 相似文献
38.
Stabilization of phage T4 lysozyme by engineered disulfide bonds. 总被引:14,自引:2,他引:12
M Matsumura W J Becktel M Levitt B W Matthews 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(17):6562-6566
Four different disulfide bridges (linking positions 9-164, 21-142, 90-122, and 127-154) were introduced into a cysteine-free phage T4 lysozyme at sites suggested by theoretical calculations and computer modeling. The new cysteines spontaneously formed disulfide bonds on exposure to air in vitro. In all cases the oxidized (crosslinked) lysozyme was more stable than the corresponding reduced (noncrosslinked) enzyme toward thermal denaturation. Relative to wild-type lysozyme, the melting temperatures of the 9-164 and 21-142 disulfide mutants were increased by 6.4 degrees C and 11.0 degrees C, whereas the other two mutants were either less stable or equally stable. Measurement of the equilibrium constants for the reduction of the engineered disulfide bonds by dithiothreitol indicates that the less thermostable mutants tend to have a less favorable crosslink in the native structure. The two disulfide bridges that are most effective in increasing the stability of T4 lysozyme have, in common, a large loop size and a location that includes a flexible part of the molecule. The results suggest that stabilization due to the effect of the crosslink on the entropy of the unfolded polypeptide is offset by the strain energy associated with formation of the disulfide bond in the folded protein. The design of disulfide bridges is discussed in terms of protein flexibility. 相似文献
39.
40.