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1.
The present paper reports data on secular trends in the stature of Brazilian Navy recruits born from 1940 to 1965. The final sample included 3269 individuals aged 18.00-18.99. Statistics performed were: ANOVA (one-way and two-way), Sheffe test, simple linear regression between stature and year of birth, and multiple linear regression adjusting for level of schooling (beta coefficient) and chi-square. Results indicated a progressive growth trend in stature of 0.1 cm/yr. for the country as a whole. The trend was also observed for nearly all regions and two out of three levels of schooling and can be explained by improvement in some of the country's health indicators. One important characteristic was a higher level of schooling observed among Navy recruits, suggesting that these individuals represent a highly select group, and that therefore data on the Navy cannot be applied directly to the Brazilian population as a whole.  相似文献   

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Trichomonacidal activity in vitro of 2 newly synthesized derivatives of benzoizothiazolinon (BIT) in comparison with metronidazole was determined by calculating lethal concentration for 50% trichomonal population (C50). Experiments were carried out on 2 strains of T. vaginalis and 2 strains of T. anseris. Both preparations showed considerably higher trichomonacidal activity than metronidazole. Mean values of trichomonacidal activity of N-morpholinomethyl-1,2-benzoizothiazolinon-3 for T. vaginalis and T. anseris amounted to 885 and 1997 respectively, and were 6 and 8 times higher than those of hydrochloride of N-piperydynomethyloamide of (5-chloro-1,2-benzoizothiazolinon-3ylo-2)-acetic acid. The lowest trichomonacidal activity of hydrochloride of N-piperydynomethylamide of (5-chloro-1,2-benzoizotiazolinon-3ylo-2)-acetic acid was 10-fold higher than that of N-morpholinomethyl-1,2-benzoizothiazolinon-3 and several hundred times lower than metronidazole concentration.  相似文献   

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We report on papers concerning in topic "Diseases of the breast", which were published in the Zentralblatt für Gyn?kologie during the first half of the 20th century. Only 26 publications about senologic problems were found in 44 years. Papers about the mammary theory of eclampsia, mastitis, plastic operations and breast cancer are reported.  相似文献   

4.
It has been established that once macrophages become activated, they pass through different stages of functional activity. Mouse macrophages activated by BCG "exerted" pronounced cytotoxic effects for 2-5 days to be followed later by growth-stimulating ones. However, in other experiments, the cytotoxic effect was either absent or occurred at later stages which was probably due to a certain functional state of macrophages before activation. The synthesis of TGF-beta increased 1-2 days after activation with BCG vaccine, lipopolysacharide and gamma radiation. An increase in mRNA TGF-beta i expression was observed only 5 days after activation of macrophages.  相似文献   

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Orthodontic treatment with fixed appliances increases the caries risk in young persons. The aim of this study was to apply a new caries diagnostic method, quantitative laser fluorescence, for longitudinal in vivo quantification of changes in incipient enamel lesions related to fixed orthodontic appliances. Seven young patients with active caries lesions disclosed at removal of the orthodontic brackets and bands were enrolled in the study. Caries preventive measures were intensified, including dietary advice, oral hygiene instructions, and the regular use of a fluoride dentifrice. The caries lesions were monitored with the quantitative laser fluorescence method after removal of the brackets and once a month thereafter. For each lesion, three quantities were measured: lesion area (mm2), mean fluorescence loss (%) over the lesion, and maximum loss of fluorescence (%) in the lesion. During a 1-year follow-up period, the areas of the lesions decreased and the enamel fluorescence lost was partly regained indicating that a remineralization process had occurred. It was concluded that quantitative laser fluorescence seems suitable for in vivo monitoring of mineral changes in incipient enamel lesions, and useful for the evaluation of preventive measures in caries prone persons, such as orthodontic patients.  相似文献   

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Transforming growth factor-beta (TGF-beta) is secreted by many cell types as part of a large latent complex composed of three subunits: TGF-beta, the TGF-beta propeptide, and the latent TGF-beta binding protein (LTBP). To interact with its cell surface receptors, TGF-beta must be released from the latent complex by disrupting noncovalent interactions between mature TGF-beta and its propeptide. Previously, we identified LTBP-1 and transglutaminase, a cross-linking enzyme, as reactants involved in the formation of TGF-beta. In this study, we demonstrate that LTBP-1 and large latent complex are substrates for transglutaminase. Furthermore, we show that the covalent association between LTBP-1 and the extracellular matrix is transglutaminase dependent, as little LTBP-1 is recovered from matrix digests prepared from cultures treated with transglutaminase inhibitors. Three polyclonal antisera to glutathione S-transferase fusion proteins containing amino, middle, or carboxyl regions of LTBP-1S were used to identify domains of LTBP-1 involved in cross-linking and formation of TGF-beta by transglutaminase. Antibodies to the amino and carboxyl regions of LTBP-1S abrogate TGF-beta generation by vascular cell cocultures or macrophages. However, only antibodies to the amino-terminal region of LTBP-1 block transglutaminase-dependent cross-linking of large latent complex or LTBP-1. To further identify transglutaminase-reactive domains within the amino-terminal region of LTBP-1S, mutants of LTBP-1S with deletions of either the amino-terminal 293 (deltaN293) or 441 (deltaN441) amino acids were expressed transiently in CHO cells. Analysis of the LTBP-1S content in matrices of transfected CHO cultures revealed that deltaN293 LTBP-1S was matrix associated via a transglutaminase-dependent reaction, whereas deltaN441 LTBP-1S was not. This suggests that residues 294-441 are critical to the transglutaminase reactivity of LTBP-1S.  相似文献   

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BACKGROUND: Cytokine genes encode proteins that modulate immune system responses. Modification of tumor cells by the introduction of cytokine genes has been used as a strategy to augment host immunity. Interleukin 7 (IL-7) gene transfer enhances the immune response to tumor cells and can result in tumor regression. Transforming growth factor-beta 1 (TGF-beta 1) is a potent immunosuppressive cytokine produced by many tumors. We have previously reported that recombinant IL-7 decreases the expression of TGF-beta 1 by murine macrophages. PURPOSE: This study investigates the inhibition of tumor-derived TGF-beta 1 production as a possible mechanism for the enhanced antitumor immunity that accompanies IL-7 gene transfer. METHODS: A fibrosarcoma cell line (FSA-JmIL-7) genetically modified to produce IL-7 was used to evaluate the effects of IL-7 on tumor production of TGF-beta 1. The control cell line (FSA-Jneo) originated from the same parental fibrosarcoma cell line (FSA) and was produced by transduction with the same retroviral vector without the IL-7 gene. FSA-Jneo and FSA-JmIL-7 tumor cells were evaluated for the expression of TGF-beta 1 messenger RNA (mRNA). To determine if the observed change in TGF-beta 1 mRNA was associated with an alteration in protein secretion, we compared supernatants from tumor cell cultures for TGF-beta 1 production. Specific anti-TGF-beta 1 monoclonal antibody (MAb) was used to confirm the role of TGF-beta 1 in these assays. RESULTS: Compared with FSA parental and FSA-Jneo cells, FSA-JmIL-7 cells expressed TGF-beta 1 mRNA at a lower level. Compared with supernatants from FSA-Jneo cells, FSA-JmIL-7 supernatants contained consistently lower levels of TGF-beta 1 activity (P < .05). In addition, FSA-Jneo supernatants suppressed lymphocyte proliferation to a significantly greater degree than supernatants from FSA-JmIL-7 cells (P < .05). Studies with anti-TGF-beta 1 MAb added to the supernatants confirmed the role of TGF-beta 1 in inhibition of lymphocyte proliferation. CONCLUSION: These findings suggest that IL-7 gene transfer inhibits the production of TGF-beta 1 by tumor cells and thus may enhance the efficacy of the host's antitumor immune response. IMPLICATION: The regulation of endogenous tumor-derived cytokines in response to cytokine gene transfer may contribute to altered immune responses in the tumor microenvironment and thus may be an important additional parameter to assess in gene therapy.  相似文献   

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An immunohistochemical approach was utilized to evaluate the cellular distribution of transforming growth factor-beta 1 (TGF beta 1) and transforming growth factor beta 2 (TGF beta 2) at different stages of follicle development in the prepubertal mouse ovary under the following conditions: (i) after pregnant mare's serum gonadotrophin (PMSG) treatment; (ii) after PMSG and human chorionic gonadotrophin (HCG) treatment; (iii) after PMSG and HCG treatment plus mating. In the immature ovary, TGF beta 1 and TGF beta 2 immunoreactivities are localized in theca and granulosa cells and in oocytes. After PMSG treatment, TGF beta 1 and TGF beta 2 immunoreactivities are localized in granulosa cells; in addition, TGF beta 2 staining is noted in the matrix surrounding antral cells. Staining for both TGR beta 1 and TGF beta 2 drops in the theca but persists in the oocyte. PMSG plus HCG treatment results in a significant increase in TGF beta 1 and TGF beta 2 immunoreactivity in the theca and in the maintenance of TGF beta 1 staining in both basal granulosa cells and cumulus cells whereas TGF beta 2 immunoreactivity is essentially localized in the matrix surrounding cumulus cells. Staining for TGF beta 1 and TGF beta 2 persists in the oocyte. Following PMSG plus HCG treatment and mating, TGF beta 1 immunoreactivity is localized in the luteal cells of corpora lutea and TGF beta 2 shows a similar localization pattern. This study provides evidence that TGF beta 1 and TGF beta 2 peptides are expressed in specific cell types during induced follicular maturation in the mouse ovary.  相似文献   

12.
The present experiments examined the effects of posttraining intrahippocampal injections of the degradative enzyme-resistant methylcarbamyl analog of the bioactive phospholipid platelet-activating factor (mc-PAF) and the platelet-activating factor (PAF) receptor antagonists BN52021 and BN 50730 on memory in male Long-Evans rats trained in a hidden platform version of the Morris water maze. Following an eight-trial training session, rats received a unilateral intrahippocampal injection of mc-PAF (0.5, 1.0, or 2.0 microgram/0.5 microliter), lyso-PAF (1.0 microgram/0.5 microliter), the cell surface PAF receptor antagonist BN 52021 (0.25, 0.5, or 1.0 micrigram/0.5 microliter/, the intracellular PAF receptor antagonist BN 50730 (2.0, 5.0, or 10.0 microgram/0.5 microliter), or vehicle (50% DMSO in 0.9% saline; 0.5 microliter). On a retention test conducted 24 h after training, the escape latencies of rats administered mc-PAF (1.0 or 2.0 microgram) were significantly lower than those of the vehicle-injected controls, demonstrating a memory-enhancing effect of mc-PAF. Injections of lyso-PAF, a structurally similar metabolite of PAF, had no influence on memory, indicating that the memory-enhancing effect of mc-PAF is not caused by membrane perturbation by the phospholipid. The retention test escape latencies of rats administered BN 52021 (0.5 microgram) and BN 50730 (5.0 or 10 microgram) were significantly higher than those of the controls, indicating a memory impairing effect of both PAF antagonists. When mc-PAF, BN 52021, or BN 50730 was administered 2 h posttraining, no effect on retention was observed, indicating a time-dependent effect of the neuroactive substances on memory storage. The findings suggest a role for endogenous PAF in hippocampal-dependent memory processes.  相似文献   

13.
This is a case report of a 43-year-old woman who received a transplant for end-stage liver disease due to hereditary hemorrhagic telangiectasia and fibropolycystic liver disease. This is an uncommon association of two autosomal-dominant conditions with defined genetic and molecular defects. The liver showed extensive vascular malformations of arteries and veins as well as telangiectasia and fibrosis. In addition, there were cystically dilated ducts containing inspissated bile and extensive von Meyenburg complexes. This case raises interesting questions about the possible relationship of these genes and their gene products, both of which are related to cell-matrix interactions and are strongly associated with blood vessels, one of them being expressed on endothelial cells and the other being developmentally important in blood vessels.  相似文献   

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One human body is composed of 6 x 10(13) cells, and eyes are also composed of many cells of different functions. The cellular functions and intercellular interaction are regulated by many regulators including cytokines and growth factors to maintain the homeostasis. The transforming growth factor-beta (TGF-beta) superfamily, a large family of multifunctional factors, regulates various cellular functions, including cellular proliferation, migration, differentiation, apoptosis and extracellular matrix production. The TGF-beta superfamily contains about 30 multifunctional factors, and is divided into several families according to the sequence homology. The TGF-beta family, the activin family, and bone morphogenic proteins belong to the TGF-beta superfamily. TGF-beta superfamily members transduce signals through type I and type II serine/threonine type transmembrane receptors. The signals are transduced from receptors through nuclei by Smad family members, which are phosphorylated by the activated type I receptors and translocate from cytoplasm into nuclei. TGF-beta family members and the TGF-beta superfamily receptor family are expressed in ocular tissues including the cornea, ciliary epithelium, lens epithelium, retina, and blood vessels. This observation suggests the importance of the TGF-beta superfamily in eyes. Smad family members (Smad 1, Smad 2, Smad 3 and Smad 4) are expressed in the cultured retinal pigmant epithelial cell line (D407), in which TGF-beta and activin A stimulate the translocation of Smad 2, but not Smad 1 into nuclei, whereas bone morphogenetic protein (BMP) stimulates that of Smad 1, but not Smad 2. TGF-beta superfamily members play important roles in the pathogenesis of retinal neovascularization and in the wound healing process of corneal tissue. TGF-beta inhibits the endothelial functions, but, stimulates angiogenesis in vivo. TGF-beta is involved in the formation of abnormal connective tissue in corneal wound healing. In these processes, many cytokines and growth factors are involved, interacting with each other and forming networks. It is mandatory to clarify the networks to investigate molecular pathogenesis and new therapeutic agents.  相似文献   

15.
A new instrument for laparoscopic access consists of a trocarless, reusable, visual-access cannula with an external thread that ends in a blunt tip. The device has no sharp ends or moving parts. The cannula does not transect but radially stretches and elevates vessels, fascia, and muscle fibers, preserving the fascia's natural gridiron shutter mechanism at the access site. The outer thread stabilizes the cannula, and no fascial suture is necessary. In a prospective clinical trial between 1994 and 1997, the instrument was used in 203 patients requiring 234 access ports for diagnostic and operative laparoscopies. No device-related complications or failed attempts were recorded. The cannula caused less tissue trauma at access sites, and may decrease the frequency of hernias and postoperative access site pain.  相似文献   

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PURPOSE: Anterior subcapsular cataracts are characterized by the appearance of opaque plaques of abnormal cells. Distinctive spindle-shaped cells containing alpha-smooth muscle actin are present and are associated with wrinkling of the overlying lens capsule. Accumulations of extracellular matrix, including type I collagen, also are found. The authors previously reported that transforming growth factor-beta (TGF-beta) induces similar aberrant morphologic changes in lens epithelial explants. More recently, they identified alpha-smooth muscle actin in explants cultured with TGF-beta. The aim of this study was to determine whether TGF-beta induces comparable cataractous changes in whole lenses and to examine the effects of this treatment on the transparency of the lens. METHODS: Whole lenses from 21-day-old rats were cultured in defined serum-free medium with TGF-beta 2 or without added growth factors for 5 days. Lenses were then photographed and prepared for histology and immunolocalization. RESULTS: Lenses cultured with TGF-beta developed distinct anterior opacities just beneath the lens capsule. Histologically, clumps of abnormal cells corresponded with these opacities. Spindle-shaped cells, which contained alpha-smooth muscle actin, were present, and the overlying capsule was often wrinkled. The clumps contained accumulations of type I collagen, laminin, and heparan sulphate proteoglycan. In contrast, lenses cultured without growth factors remained transparent, retained normal lens morphology, and did not accumulate alpha-smooth muscle actin or type I collagen. CONCLUSIONS: These results show that TGF-beta induces whole lenses to form opacities that contain morphologic and biochemical markers for subcapsular cataract.  相似文献   

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Amyloid beta-peptide (Abeta) of 39-42 amino acid residues is a major constituent of Alzheimer's disease neurite plaques. Abeta aggregates (fibrils) are believed to be responsible for neuronal damage and dysfunction, as well as microglia and astrocyte activation in disease lesions by multiple mechanisms. Since Abeta aggregates possess the multiple valencies of an FAED motif (20th to 23rd amino acid residues), which resembles the putative transforming growth factor-beta (TGF-beta) active site motif, we hypothesize that Abeta monomers and Abeta aggregates may function as TGF-beta antagonists and partial agonists, analogous to previously described monovalent and multivalent TGF-beta peptide antagonists and agonists (Huang, S. S., Liu, Q., Johnson, F. E., Konish, Y., and Huang, J. S. (1997) J. Biol. Chem. 272, 27155-27159). Here, we report that the Abeta monomer, Abeta-(1-40) and its fragment, containing the motif inhibit radiolabeled TGF-beta binding to cell-surface TGF-beta receptors in mink lung epithelial cells (Mv1Lu cells). Abeta-(1-40)-bovine serum albumin conjugate (Abeta-(1-40)-BSA), a multivalent synthetic analogue of Abeta aggregates, exhibited cytotoxicity toward bovine cerebral endothelial cells and rat post-mitotic differentiated hippocampal neuronal cells (H19-7 cells) and inhibitory activities of radiolabeled TGF-beta binding to TGF-beta receptors and TGF-beta-induced plasminogen activator inhibitor-1 expression, that were approximately 100-670 times more potent than those of Abeta-(1-40) monomers. At less than micromolar concentrations, Abeta-(1-40)-BSA but not Abeta-(1-40) monomers inhibited proliferation of Mv1Lu cells. Since TGF-beta is an organizer of responses to neurodegeneration and is also found in neurite plaques, the TGF-beta antagonist and partial agonist activities of Abeta monomers and aggregates may play an important role in the pathogenesis of the disease.  相似文献   

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