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61.
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
62.
Milton Carlos Gon?alves Salvador Accácio Lins do Valle Mariana Carvalho Mandim Ribeiro Jefferson Ricardo Pereira 《Journal of applied oral science : revista FOB》2007,15(1):9-13
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition. 相似文献
63.
Because of its numerous etiologies, foot dermatitis can be difficult to diagnose despite of thorough history and physical examination. The differential diagnoses are challenging and include allergic contact dermatitis, dyshidrosis, juvenile plantar dermatosis, atopic dermatitis, lichen planus.
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献
64.
Lima JO dos Santos JK Pereira JF de Resende ML de Araújo EF de Queiroz MV 《Current genetics》2003,42(4):236-240
Protoplasts of the pathogenic plant fungus, Crinipellis perniciosa, were transformed to hygromycin B resistance using the pAN7-1 plasmid, which contains the Escherichia coli hph gene under the control of Aspergillus nidulans regulatory sequences. The pAN7-1 plasmid was introduced by PEG/CaCl(2) treatment. Transformation frequencies of 1.6-2.5 transformants/microg of DNA were achieved. About 54% of the transformants were abortive and 40 analyzed transformants were mitotically stable and showed different hygromycin B resistance levels. The presence of the hph gene was checked by PCR in five transformants and the integration of multiple plasmid copies into different genome sites was observed by Southern analysis. This is the first report of a C. perniciosa transformation system and represents an important step for further research into genetic manipulation of this fungal plant pathogen. 相似文献
65.
Changes in Avidity and Level of Immunoglobulin G Antibodies to Mycobacterium tuberculosis in Sera of Patients Undergoing Treatment for Pulmonary Tuberculosis
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Lenka M. Pereira Arias-Bouda Sjoukje Kuijper Anouk Van Der Werf Lan N. Nguyen Henk M. Jansen Arend H. J. Kolk 《Clinical and Vaccine Immunology : CVI》2003,10(4):702-709
Much is known about specific antibodies and their titers in patients with tuberculosis. However, little is known about the avidity of these antibodies or whether changes in avidity occur during the progression of the disease or during treatment. The aims of this study were to determine the avidity of antibodies to Mycobacterium tuberculosis in patients with pulmonary tuberculosis, to explore the value of avidity determination for the diagnosis of tuberculosis, and to study changes in levels of antibodies and their avidity during treatment. Antibody avidity was measured by an enzyme-linked immunosorbent assay with thiocyanate elution. Avidity indices and serum levels of immunoglobulin G to M. tuberculosis were determined for 22 patients with pulmonary tuberculosis before and during treatment and for 24 patients with other pulmonary diseases. Antibody levels and avidity were both significantly higher in untreated tuberculosis patients than in the controls. Avidity determination had more diagnostic potential than determination of the antibody levels. Tuberculosis patients with a long duration of symptoms had higher antibody avidity than those with a recent onset of symptoms, indicating affinity maturation of specific antibodies during active disease. In the early phase of treatment, a decrease in antibody avidity was observed for 73% of all tuberculosis patients, accompanied by an initial increase in antibody levels in 36% of these patients. These phenomena could be explained by an intense stimulation of the humoral response by antigens released from killed bacteria, reflecting early bactericidal activity of antituberculous drugs leading to the production of low-affinity antibodies against these released antigens. 相似文献
66.
Genomic analysis of the nuclear receptor family: new insights into structure, regulation, and evolution from the rat genome
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Zhang Z Burch PE Cooney AJ Lanz RB Pereira FA Wu J Gibbs RA Weinstock G Wheeler DA 《Genome research》2004,14(4):580-590
Completion of the Rattus norvegicus genome sequence enabled a global inventory and analysis of the nuclear receptors (NRs) in three mammalian species. Forty-nine NR members were found in mouse, 48 in human. Forty-seven were found in the rat, with gaps at the locations expected for the other two. Pairwise comparisons of their distribution in rat, mouse, and human identified 11 syntenic NR gene blocks, including three small clusters of two or three closely related genes, each spanning 40 kb to 1700 kb. The exon structure of the ligand-binding domain suggests that exon shuffling has played a role in the evolution of this family. An invariant splice junction in all members of the NR family except LXRbeta suggests a functional role for the intron. The ligand-binding domains of PXR and CAR are among the most divergent in the family. Their higher nucleotide substitution rates may be related to the central role played by these two NRs in the metabolism of the foreign compounds and may have resulted from limited positive selection. 相似文献
67.
F G Araujo P M Coelho L H Pereira J Pellegrino 《Clinical and experimental immunology》1977,28(2):289-291
Skin-graft rejection in mice experimentally infected with Schistosoma mansoni is delayed when grafting is performed 60 days after the infection. In mice infected 30 days prior to the grafting, the grafts were rejected at the same time both in infected and in control animals. This observation indicates that impairment of cell-mediated immune response occurs in mice with mature S. mansoni infections. 相似文献
68.
Herpes simplex virus 1 (HSV-1) glycoprotein B (gB) is one of several envelope glycoproteins required for virion infectivity and is the only one known to oligomerize into homodimers. To study the conformational constraints for translocation of HSV-1 gB to the surface of eukaryotic cells, we analyzed the transport through the exocytic pathway of the wild-type glycoprotein and of mutant forms with insertions in the ectodomain and intracellular carboxy terminus. Transient expression of the glycoproteins in COS-1 cells showed that an insertion at position 479 in the amino-terminal ectodomain of gB, shown previously by reactions with monoclonal antibodies to have altered the conformation of the molecule, also had a drastic effect on transport, precluding exit of the mutant from the endoplasmic reticulum (ER) and transport to the Golgi and the plasma membrane. The fact that the mutant, gB-(Lk479), formed dimers suggests that local changes in assembled regions caused the transport defect. Mutants containing insertions at residues 600 of the ectodomain and 810 in the intracellular domain were slightly retarded in their rate of transport from the ER to the Golgi. The glucose-regulated proteins GRP78 and GRP94, which are resident proteins of the ER, associated with partially glycosylated, faster-migrating forms of gB but not with the fully processed, more slowly migrating product. GRP78 and GRP94 formed complexes with the mutant gB-(Lk479), which was degraded in the ER. Our results indicate that GRP78, and perhaps also GRP94, acts as a chaperone in the assembly of native gB oligomers and also binds to aberrant forms of the molecule, arresting their transport from the ER and possibly serving as markers for protein degradation in this compartment of the exocytic pathway. 相似文献
69.
Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance
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Rodrigo Ribeiro-Rodrigues Tatiana Resende Co John L. Johnson Fabiola Ribeiro Moises Palaci Ricardo T. S Ethel L. Maciel Fausto E. Pereira Lima Valderio Dettoni Zahra Toossi W. Henry Boom Reynaldo Dietze Jerrold J. Ellner Christina S. Hirsch 《Clinical and Vaccine Immunology : CVI》2002,9(4):818-823
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy. 相似文献
70.