962 resultados para growth differentiation factor 9


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Mutations in the FGFR3 gene cause the phenotypic spectrum of FGFR3 chondrodysplasias ranging from lethal forms to the milder phenotype seen in hypochondroplasia (Hch). The p.N540K mutation in the FGFR3 gene occurs in ∼70% of individuals with Hch, and nearly 30% of individuals with the Hch phenotype have no mutations in the FGFR3, which suggests genetic heterogeneity. The identification of a severe case of Hch associated with the typical mutation c.1620C > A and the occurrence of a c.1150T > C change that resulted in a p.F384L in exon 10, together with the suspicion that this second change could be a modulator of the phenotype, prompted us to investigate this hypothesis in a cohort of patients. An analysis of 48 patients with FGFR3 chondrodysplasia phenotypes and 330 healthy (control) individuals revealed no significant difference in the frequency of the C allele at the c.1150 position (p = 0.34). One patient carrying the combination `pathogenic mutation plus the allelic variant c.1150T > C' had a typical achondroplasia (Ach) phenotype. In addition, three other patients with atypical phenotypes showed no association with the allelic variant. Together, these results do not support the hypothesis of a modulatory role for the c.1150T > C change in the FGFR3 gene.

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Squamous cell carcinoma is the most common neoplasm of the larynx, and its evolution depends on tumor staging. Vascular endothelial growth factor is a marker of angiogenesis, and its expression may be related to increased tumor aggressiveness, as evidenced by the presence of cervical lymphatic metastases. To evaluate the expression of the vascular endothelial growth factor marker in non-glottic advanced squamous cell carcinoma of the larynx (T3/T4) and correlate it with the presence of cervical lymph node metastases. Retrospective clinical study and immunohistochemical analysis of vascular endothelial growth factor through the German scale of immunoreactivity in products of non-glottic squamous cell carcinomas. This study analyzed 15 cases of advanced non-glottic laryngeal tumors (T3/T4), four of which exhibited cervical lymphatic metastases. There was no correlation between vascular endothelial growth factor expression and the presence of cervical metastases. Although vascular endothelial growth factor was expressed in a few cases, there was no correlation with the spread of cervical lymph metastases.

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Objective: To evaluate the effects of local administration of epidermal growth factor (EGF) located within liposomes on recruitment of osteoclasts during mechanical force in rats. Materials and Methods: An orthodontic elastic band was inserted between the left upper first and second molars, to move mesially the first molar. Rats were randomly divided into 4 groups (n = 8): EGF (2 ng/mu L) located within liposomes (group 1), liposomes only (group 2), soluble EGF (2 ng/mu L; group 3), or vehicle alone (group 4). The solutions were injected into the region of the root furcation of the left first molar after elastic band insertion. Tooth movement was measured using a plaster model of the maxilla, and the number of osteoclasts recruited at the pressure side of the first molar was histologically evaluated. Results: Intergroup analysis showed that there was no significant difference between group 2 and group 4 (P >.05) and between group 1 and group 3 (P >.05). However, group 1 and group 3 exhibited greater differences in tooth movement than group 2 and group 4 (P <.05). On the other hand, group 1 showed greater tooth movement than groups 2 and 4 with statistical significance (P <.01). The increase in the number of osteoclasts in group 1 was significantly higher than in the other groups (P <.05). Conclusion: Exogenous EGF-liposome administration has an additive effect when compared with soluble EGF on the rate of osteoclast recruitment, producing faster bone resorption and tooth movement.

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Background: The vascular endothelial growth factor (VEGF) is a major promoter of endothelial growth and migration. Some studies have shown a correlation between expression of this growth factor and prognosis in several cancers, including well-differentiated thyroid cancer. Aim: We studied VEGF expression, local invasiveness, and other prognostic factors in papillary thyroid carcinoma (PTC) to test the hypothesis that the expression of VEGF is correlated with the degree of invasion of PTC. Patients and Methods: Clinical and pathological data of 76 patients with PTC were retrospectively reviewed. Group 1 consisted of patients with gross locally invasive tumors, group 2 consisted of patients with only invasion of the thyroid capsule, and group 3 consisted of patients with noninvasive PTC. Results: VEGF expression was noted within the tumor in all groups of PTC patients but was absent in the surrounding normal tissue. Older patients had higher expression of VEGF than younger patients. The age of patients with strong reaction to VEGF was 46 +/- 14 (mean +/- standard deviation), and that in patients with a weaker reaction was 39 +/- 16 (p<0.05). Only 20% of patients with a follicular variant of PTC had a strong reaction to VEGF compared with 68% of patients with classical PTC (p<0.01). Conclusions: VEGF expression appears to be an early event in the development of PTC. Whether VEGF expression promotes the progression of PTC is not known, but the answer to this question may be important in view of its greater expression in older patients, a group whose prognosis in PTC is worse.

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Vascular endothelial growth factor (VEGF) is a homodimeric glycoprotein produced mostly in endothelial cells and its transcription is regulated by a variety of growth factors and cytokines. VEGF plays many relevant roles, and three functional polymorphisms in the promoter region of the VEGF gene (C-2578A, G-1154A, and G-634C) have been associated with disease conditions. Although some studies suggest that interethnic differences exist in the distribution of these variants, no previous study has examined this hypothesis in admixed populations. We examined the distribution of these three clinically relevant VEGF single-nucleotide polymorphisms in 175 white and 185 black subjects. We have also estimated the haplotype distribution and assessed associations between these variants. Although the A-2578 and A-1154 variants were more common in whites (39% and 29%, respectively) than in blacks (29% and 16%, respectively; both p < 0.05), no significant interethnic differences were found with regards to the G-634C polymorphism. While the haplotype including the C-2578, G-1154, and G-634 variants was the most common in both ethnic groups, it was more common in blacks than in whites (p < 0.05). The haplotype including the C-2578, A-1154, and G-634 alleles and the haplotype including the C-2578, A-1154, and C-634 alleles were more common in whites than in blacks (both p < 0.05). These results show marked interethnic differences in the distribution of genetic variants of VEGF that may explain, at least in part, interethnic disparities in the susceptibility to cardiovascular diseases.

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Vascular endothelial growth factor (VEGF) production is regulated by growth factors and inflammatory cytokines, and VEGF plays a role in migraine. We examined for the first time whether three functional polymorphisms in the promoter region of VEGF gene (C(-2578)A, G(-1154A), and G(-634C)) and VEGF haplotypes are associated with migraine. We studied 114 healthy women without migraine and 175 women with migraine (129 without aura, and 46 with aura). We found no differences in the distributions of VEGF genotypes and alleles (p > 0.05). However, the CAC haplotype was more frequent in controls than in migraine patients, and the AGC haplotype was more frequent in patients with migraine with aura than in controls (both p < 0.05). These findings suggest that VEGF haplotypes affect susceptibility to migraine.

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The aim of the current study was to evaluate the expression of vascular endothelial growth factor (VEGF) and the microvascular density in canine soft-tissue sarcomas. Immunohistochemistry for VEGF expression was performed on 20 canine neoplasms by the streptavidin-biotin-peroxidase method using an anti-VEGF mouse monoclonal antibody (ab-119). The Volume fraction of microvessels in the sarcomas was quantified in hematoxylin and eosin-stained tissue sections. At least 10 fields of view (40x magnification) per neoplasm were analyzed by positioning a grid with 100 points and counting the microvessels that fell into the intersection points. This percentage was considered the volume fraction of these microvessels in the tumor section. VEGF expression was detected in 65% of the neoplasms. In 92.3% of the neoplasms, the expression occurred in the peritumor region; in 46.15%, in the intratumor region; and in 38.46%, the expression was present in both regions. The cells responsible for VEGF expression were fibroblasts and macrophages in the peritumor region or in the pseudocapsule and neoplastic cells in the intratumor region. Greater intratumoral VEGF was expressed in hemangiopericytomas (P = 0.04). No difference was present in the volume fraction of tumor microvessels between VEGF-positive and VEGF-negative neoplasms (P = 0.3416) or for the different types of neoplasms (P = 0.5). The results of this study suggest that VEGF participates in the angiogenesis of soft-tissue sat-coma in dogs. Additional research will be necessary to elucidate the contribution of VEGF to the progression of malignancy.

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Objective: This study investigated and correlated the kinetic expression of vascular endothelial growth factor (VEGF)-A(165) messenger ribonucleic acid (mRNA) with the associated use or not of an infrared laser and a visible red laser during the wound healing in rats. Background Data: There is a lack of scientific evidence demonstrating the influence of low-level laser therapy (LLLT) on the expression of VEGF mRNA in vivo. Materials and Methods: Forty-five Wistar rats were randomly allocated to one of three groups: I (n = 5, nonoperated animals), II (n = 25, operated animals), and III (n = 25, animals operated and subjected to laser irradiation). A surgical wound was performed using a scalpel in the right side of the tongue of operated animals. In group III, two sessions of laser irradiation were performed, one right after the surgical procedure (infrared laser, 780 nm, 70mW, 35 J/cm(2)) and the other 48 h later (visible red laser, 660 nm, 40mW, 5J/cm(2)). Five animals each were sacrificed 1, 3, 5, and 7 days postoperatively in groups II and III, and samples of tongue tissue were obtained. The animals of group I were sacrificed on day 7. Total RNA was extracted using guanidine-isothiocyanate-phenol-chloroform method. The results of horizontal electrophoresis after reverse transcription polymerase chain reaction permitted the ratio of VEGF-A(165) mRNA and glyceraldehyde 3-phosphate dehydrogenase mRNA expression for groups I, II, and III to be assessed (two-way analysis of variance and Tukey test, p<0.05). Results: The expression of VEGF-A(165) mRNA in group II (0.770 +/- 0.098) was statistically greater than that observed in groups I (0.523 +/- 0.164) and III (0.504 +/- 0.069) in the first day after surgery (p<0.05). Significant differences between the groups were not observed in other time periods. Conclusion: LLLT influenced the expression of VEGF-A(165) mRNA during wound healing after a surgical procedure on the tongue of Wistar rats.

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Due to the worldwide increase in demand for biofuels, the area cultivated with sugarcane is expected to increase. For environmental and economic reasons, an increasing proportion of the areas are being harvested without burning, leaving the residues on the soil surface. This periodical input of residues affects soil physical, chemical and biological properties, as well as plant growth and nutrition. Modeling can be a useful tool in the study of the complex interactions between the climate, residue quality, and the biological factors controlling plant growth and residue decomposition. The approach taken in this work was to parameterize the CENTURY model for the sugarcane crop, to simulate the temporal dynamics of aboveground phytomass and litter decomposition, and to validate the model through field experiment data. When studying aboveground growth, burned and unburned harvest systems were compared, as well as the effect of mineral fertilizer and organic residue applications. The simulations were performed with data from experiments with different durations, from 12 months to 60 years, in Goiana, TimbaA(0)ba and Pradpolis, Brazil; Harwood, Mackay and Tully, Australia; and Mount Edgecombe, South Africa. The differentiation of two pools in the litter, with different decomposition rates, was found to be a relevant factor in the simulations made. Originally, the model had a basically unlimited layer of mulch directly available for decomposition, 5,000 g m(-2). Through a parameter optimization process, the thickness of the mulch layer closer to the soil, more vulnerable to decomposition, was set as 110 g m(-2). By changing the layer of mulch at any given time available for decomposition, the sugarcane residues decomposition simulations where close to measured values (R (2) = 0.93), contributing to making the CENTURY model a tool for the study of sugarcane litter decomposition patterns. The CENTURY model accurately simulated aboveground carbon stalk values (R (2) = 0.76), considering burned and unburned harvest systems, plots with and without nitrogen fertilizer and organic amendment applications, in different climates and soil conditions.

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This work was undertaken to provide further insight into the role of mammalian target of rapamycin complex 1 (mTORC1) in skeletal muscle regeneration, focusing on myofiber size recovery. Rats were treated or not with rapamycin, an mTORC1 inhibitor. Soleus muscles were then subjected to cryolesion and analyzed 1, 10, and 21 days later. A decrease in soleus myofiber cross-section area on post-cryolesion days 10 and 21 was accentuated by rapamycin, which was also effective in reducing protein synthesis in these freeze-injured muscles. The incidence of proliferating satellite cells during regeneration was unaltered by rapamycin, although immunolabeling for neonatal myosin heavy chain (MHC) was weaker in cryolesion+rapamycin muscles than in cryolesion-only muscles. In addition, the decline in tetanic contraction of freeze-injured muscles was accentuated by rapamycin. This study indicates that mTORC1 plays a key role in the recovery of muscle mass and the differentiation of regenerating myofibers, independently of necrosis and satellite cell proliferation mechanisms. Muscle Nerve 42: 778-787,2010

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Shoot elongation of Hancornia speciosa, an endangered tree from the Brazilian savannah ""Cerrado"", is very slow, thus limiting nursery production of plants. Gibberellins (GAs) A(1), A(3), and A(5), and two inhibitors of GA biosynthesis, trinexapac-ethyl and ancymidol were applied to shoots of Hancornia seedlings. GA(1) and GA(3) significantly stimulated shoot elongation, while GA(5) had no significant effect. Trinexapac-ethyl and ancymidol, both at 100 A mu g per seedling, inhibited shoot elongation up to 45 days after treatment, though the effect was statistically significant only for ancymidol. Somewhat surprisingly, exogenous GA(3) more effectively stimulated shoot elongation in SD-grown plants, than in LD-grown plants. The results from exogenous application of GAs and inhibitors of GA biosynthesis imply that Hancornia shoot growth is controlled by GAs, and that level of endogenous growth-active GAs is likely to be the limiting factor for shoot elongation in Hancornia. Application of GAs thus offer a practical method for nursery production of Hancornia seedlings for outplanting into the field.

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Background: Statins induces cell cycle arrest, apoptosis, reduction of angiogenic factors, inhibition of the endothelial growth factor, impairing tissue adhesion and attenuation of the resistance mechanisms. The aim of this study was evaluate the anti tumoral activity of simvastatin in a B16F10 melanoma-mouse model. Methods: Melanoma cells were treated with different concentrations of simvastatin and assessed by viability methods. Melanoma cells (5 x 10(4)) were implanted in two month old C57Bl6/J mice. Around 7 days after cells injection, the oral treatments were started with simvastatin (5 mg/kg/day, p.o.). Tumor size, hematological and biochemical analyses were evaluated. Results: Simvastatin at a concentration of 0.8 mu M, 1.2 mu M and 1.6 mu M had toxic effect. Concentration of 1.6 mu M induced a massive death in the first 24 h of incubation. Simvastatin at 0.8 mu M induces early cell cycle arrest in G0/G1, followed by increase of hypodiploidy. Tumor size were evaluated and the difference of treated group and control, after ten days, demonstrates that simvastatin inhibited the tumor expansion in 68%. Conclusion: Simvastatin at 1.6 mu M, presented cytototoxicity after 72 h of treatment, with an intense death. In vivo, simvastatin being potentially useful as an antiproliferative drug, with an impairment of growth after ten days.

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The effects of conjugating cholesterol to either or both ends of a phosphorothioate (PS) oligonucleotide were analyzed in terms of cellular uptake and antisense efficacy. The oligo sequence was directed against the p75 nerve growth factor receptor (p75), and was tested in differentiated PC12 cells, which express high levels of this protein. The addition of a single cholesteryl group to the 5'-end significantly increased cellular uptake and improved p75 mRNA downregulation compared with the unmodified PS oligo, However, only a minor degree of downregulation of p75 protein was obtained with 5' cholesteryl oligos, Three different linkers was used to attach the 5' cholesteryl group but were found not to have any impact on efficacy. Addition of a single cholesteryl group to the 3'-end led to greater p75 mRNA downregulation (31%) and p75 protein downregulation (28%) than occurred with the 5' cholesteryl oligos. The biggest improvement in antisense efficacy, both at the mRNA and protein levels, was obtained from the conjugation of cholesterol to both ends of the oligo. One of the bis-cholesteryl oligos was nearly as effective as cycloheximide at decreasing synthesis of p75, The bis-cholesteryl oligos also displayed significant efficacy at 1 mu M, whereas the other oligos required 5 mu M to be effective. The enhanced efficacy of bis-cholesteryl oligos is likely to be due to a combination of enhanced cellular uptake and resistance to both 5' and 3' exonucleases.