953 resultados para Development disorders


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The objective of this study was to estimate and contrast the occurrence of ictal and interictal cutaneous allodynia (CA) in individuals with migraine with and without temporomandibular disorders (TMD). Both TMD and CA are common in migraine and may be associated with migraine transformation from episodic into a chronic form. Herein we hypothesize that TMD contributes to the development of CA and to more severe headaches. In a clinic-based sample of individuals with episodic migraine, the presence of TMD was assessed using the research diagnostic criteria for myofascial or mixed (myofascial and arthralgic) TMD. Ictal CA was quantified using the validated Allodynia Symptom Checklist (ASC-12). The ASC-12 measures CA over the preceding month by asking 12 questions about the frequency of allodynia symptoms during headaches. Interictal CA was assessed in the domains of heat, cold and mechanical static allodynia using quantitative sensory testing. Our sample consists of 55 individuals; 40 (73%) had TMD (23 with myofascial TMD and 17 with the mixed type). CA of any severity (as assessed by ASC-12) occurred in 40% of those without TMD (reference group), 86.9% of those with myofascial TMD (P = 0.041, RR = 3.2, 95% CI = 1.5-7.0) and in 82.3% of those with mixed TMD (P = 0.02, RR = 2.5, 95% CI = 1.2-5.3). Individuals with TMD were more likely to have moderate or severe CA associated with their headaches. Interictally (quantitative sensory testing), thresholds for heat and mechanical nociception were significantly lower in individuals with TMD. Cold nociceptive thresholds were not significantly different in migraine patients with and without TMD. TMDs were also associated with change in extra-cephalic pain thresholds. In logistical regression, TMD remained associated with CA after adjusting for aura, gender and age. TMD and CA are associated in individuals with migraine.

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P>The aim of this study was to evaluate the frequency of TNFa-e microsatellites and the promoter region (TNF-308 and TNF-238) in HIV/AIDS-infected patients presenting or not lipodystrophy syndrome (LS). The design is the genetic case-control association study. Microsatellite and the TNF promoter region polymorphisms were amplified by PCR and submitted to polyacrylamide gel electrophoresis. The genotypes and allele frequencies for 67 HIV-positive patients with lipodystrophy were compared with 50 HIV-positive patients with no evidence of lipodystrophy and with 131 healthy HIV-negative individuals. The presence of the TNFa5 allele could provide HIV/AIDS patients with protection against developing LS. The presence of TNF-308G allele, as well as of its homozygote TNF-308GG, were associated with susceptibility to developing LS. In addition, the presence of the haplotype TNFe3-d3-238G-308A-c1-a5-b7 suggests protection against developing that syndrome. This study highlights that polymorphic sites spanning the region nearby the TNF locus are associated with LS development in HIV/AIDS patients.

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In the present study we evaluated the toxic effects on the male adult rat prostate of DBP exposure during fetal and lactational periods, because although many studies have addressed the influence of phthalates on the male reproductive system, only a few have discussed their possible effects on prostate development. Pregnant females were distributed into two experimental groups: Control (C) and Treated (T). The females of the T group received DBP (100 mg/kg, by gavage) from gestation day 12 to postnatal day 21, while C rats received the vehicle (corn oil). In adulthood (90 days old), the animals were euthanized. The serum and testicular testosterone levels were measured. Ventral prostate was removed and weighed. Distal segment fragments of the ventral prostate were fixed and processed for histochemistry and immunohistochemistry to detect androgen receptor (AR) and Ki67 antigens. Protein extraction from ventral prostate fragments was performed for AR immunoblotting and Gelatin zymography for MMP-2 and MMP-9 (MMP, metalloproteinase). Stereological and histopathological analyses were also performed. Serum and testicular testosterone levels and prostate weight were comparable between groups. In the T group the relative proportions (%) of epithelial (C=32.86; T=42.04*) and stromal (C=21.61; T=27.88*) compartments were increased, while the luminal compartment was decreased (C=45.54; T=30.08*), *p < 0.05. In T, disseminated inflammatory infiltrate in the stroma, associated or not with epithelial dysplasia and PIN (Prostatic Intraepithelial Neoplasia), was observed. Increases in AR expression, proliferation index and metalloproteinase 9 (MMP-9) activity were noted in T animals. In some T animals, collagen fibrils accumulated adjacent to the epithelium. As far as we are aware, this is the first report in the literature showing that phthalates could play a role in proliferative and inflammatory disorders of the rat prostate. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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Thirty-two pouch-young tammar wallabies were used to discover the generators of the auditory brainstem response (ABR) during development by the use of simultaneous ABR and focal brainstem recordings. A click response from the auditory nerve root (ANR) in the wallaby was recorded from postnatal day (PND) 101, when no central auditory station was functional, and coincided with the ABR, a simple positive wave. The response of the cochlear nucleus (CN) was detected from PND 110, when the ABR had developed 1 positive and 1 negative peak. The dominant component of the focal ANR response, the N-1 wave, coincided with the first half of the ABR P wave, and that of the focal CN response, the N-1 wave, coincided with the later two thirds. In older animals, the ANR response coincided with the ABR's N-1, wave, while the CN response coincided with the ABR's P-2, N-2 and P-3 waves, with its contribution to the ABR P-2 dominant. The protracted development of the marsupial auditory system which facilitated these correlations makes the tammar wallaby a particularly suitable model. Copyright (C) 2001 S. Karger AG, Basel.

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To discover the developmental relationship between the auditory brainstem response (ABR) and the focal inferior colliculus (IC) response, 32 young tammar wallabies were used, by the application of simultaneous ABR and focal brainstem recordings, in response to acoustic clicks and tone bursts of seven frequencies. The ic or the tammar wallaby undergoes a rapid functional development from postnatal day (PND) 114 to 160. The earliest (PND 114) auditory evoked response was recorded from the rostral IC. With development, more caudal parts of the IC became functional until age about PND 127, when all parts of the IC were responsive to sound. Along a dorsoventral direction, the duration of the IC response decreased, the peak latency shortened, while the amplitude increased, reaching a maximum value at the central IC, then decreased. After PND 160, the best frequency (BF) of the ventral IC was the highest, with values between 12.5 and 16 kHz, the BF of the dorsal IC was the lowest, varying between 3.2 and 6.4 kHz, while the BF of the central IC was between 6.4 and 12.5 kHz. Between PND 114 and 125, the IC response did not have temporal correlation with the ABR. Between PND 140 and 160, only the early components of the responses from the ventral and central IC correlated with the P4 waves of the ABR. After PND 160, responses recorded from different depths of the IC had a temporal correlation with the ABR. (C) 2001 Published by Elsevier Science B.V.

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Cytogenetic and loss of heterozygosity (LOH) studies have long indicated the presence of a tumor suppressor gene (TSG) on 90 involved in the development of melanoma, Although LOH at 90 has been reported in approximately 60% of melanoma tumors, only 5-10% of these tumors have been shown to carry CDKN2A mutations, raising the possibility that another TSG involved in melanoma maps to chromosome 90. To investigate this possibility, a panel of 37 melanomas derived from 35 individuals was analyzed for CDKN2A mutations hy single-strand conformation polymorphism analysis and sequencing. The melanoma samples were then typed for 15 markers that map to 9p13-24 to investigate LOH trends in this region. In those tumors demonstrating retention of heterozygosity at markers flanking CDKN2A and LOH on one or both sides of the gene, multiplex microsatellite PCR was performed to rule out homozygous deletion of the region encompassing CDKN2A. CDKN2A mutations were found in tumors from 5 patients [5 (14%) of 35], 4 of which demonstrated LOH across the entire region examined. The remaining tumor with no observed LOH carried two point mutations, one on each allele, Although LOH was identified at one or more markers in 22 (59%) of 37 melanoma tumors corresponding to 20 (57%) of 35 individuals, only 11 tumors from 9 individuals [9 (26%) of 35] demonstrated LOH at D9S942 and D9S1748, the markers closest to CDKN2A. Of the remaining 11 tumors with LOH, 9 demonstrated LOH at two or more contiguous markers either centromeric and/or telomeric to CDKN2A while retaining heterozygosity at several markers adjacent to CDKN2A. Multiplex PCR revealed one tumor carried a homozygous deletion extending from D9S1748 to the IFN-alpha locus. In the remaining eight tumors, multiplex PCR demonstrated that the observed heterozygosity was not attributable to homozygous deletion and stromal contamination at D9S1748, D9S942, or D9S974, as measured by comparative amplification strengths, which indicates that retention of heterozygosity with flanking LOH does not always indicate a homozygous deletion, This report supports the conclusions of previous studies that at least two TSGs involved in melanoma development in addition to CDKN2A may reside on chromosome 9p.

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This study focuses on characterizing the genetic and biological alterations associated with squamous cell carcinoma development. Normal human epidermal keratinocytes (HEKs), cells isolated from a preneoplastic lesion (IEC-1), and two neoplastic cell lines, SCC-25 and COLD-16, were grown as raft cultures, and their gene expression profiles were screened using cDNA arrays. Our data indicated that the expression levels of at least 37 genes were significantly (P less than or equal to 0.05; 1.9% of genes screened) altered in neoplastic cells compared with normal cells. Of these genes, 10 genes were up-regulated and 27 genes were down-regulated in the neoplastic cells. In addition, 51% of the genes altered in the neoplastic cells were already altered in the preneoplastic IEC-1 cells. Immunohistochemical staining of patient tumors was used to verify the cDNA array analysis. Our analysis indicated that alterations in genes associated with extracellular matrix production and apoptosis are disrupted in preneoplastic cells, whereas later stages of neoplasia are associated with alterations in gene expression for genes involved in DNA repair or epidermal growth factor (EGF) receptor/mitogen-activated protein kinase kinase (MAPKK)/MAPK/activator protein-1 (AP-1) signaling. Subsequent functional analysis of the alterations in expression of the EGF receptor/MAPKK/MAPK/AP-1 genes suggested they did not contribute to the neoplastic phenotype.

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The past decade has seen the emergence of new pathways in the development of colorectal cancer. There is now clear evidence that subsets of these tumours do not show chromosomal instability and do not follow the suppressor pathway. Instead, about 15% of colorectal cancers are characterised by microsatellite instability (MSI). This feature arises through defective DNA mismatch repair, which is related either to a germline mutation (as in hereditary non-polyposis colorectal carcinoma) or to failure to express a mismatch-repair gene. CpG-island methylation has been linked to sporadic cancers with a high frequency of MSI. This type of methylation leads to loss of gene expression when it occurs in the promoter region of a gene. Tumours may have high or low type C (cancer-related) CpG-island methylation. When methylation affects hMLH1 (mismatch repair gene), the resultant cancer has high MSI.

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Because of subtle differences between mouse and human skin, mice have traditionally not been an ideal model to study melanoma development. Understanding of the molecular mechanisms of melanoma predisposition, however, has been greatly improved by modeling various pathway defects in the mouse. This review analyzes the latest developments in mouse models of melanoma, and summarizes what these may indicate about the development of this neoplasm in humans. Mutations of genes involved in human melanoma have been recapitulated with some unexpected results, particularly with respect to the role of the two transcripts (Ink4a and Arf) encoded by the Cdkn2a locus. Both the Ink4a/pRb and Arf/p53 pathways are involved in melanoma development in mice, and possible mechanisms of cross-talk between the two pathways are discussed. We also know from mouse models that Ras/mitogen-activated protein kinase pathway activation is very important in melanoma development, either through direct activation of Ras (e.g., Hras G12V), or via activation of Ras-effector pathways by other oncogenes (e.g., Ret, Hgf/Sf). Ras can cooperate with the Arf/p53 pathway, and probably the Ink4a/Rb pathway, to induce melanoma. These three growth regulation pathways (Ink4a/pRb, Arf/p53, and Ras/mitogen-activated protein kinase) seem to represent three major axes of melanoma development in mice. Finally, we summarize experiments using genetically modified mice that have given indications of the intensity and timing of ultraviolet radiation exposure that may be most responsible for melanoma development.

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To address the hypothesis that certain disease-associated mutants of the breast-ovarian cancer susceptibility gene BRCA1 have biological activity in vivo, we have expressed a truncated Brca1 protein (trBrca1) in cell-lines and in the mammary gland of transgenic mice. Immunofluorescent analysis of transfected cell-lines indicates that trBRCA1 is a stable protein and that it is localized in the cell cytoplasm. Functional analysis of these cell-lines indicates that expression of trBRCA1 confers an increased radiosensitivity phenotype on mammary epithelial cells, consistent with abrogation of the BRCA1 pathway. MMTV-trBrca1 transgenic mice from two independent lines displayed a delay in lactational mammary gland development, as demonstrated by altered histological profiles of lobuloalveolar structures. Cellular and molecular analyses indicate that this phenotype results from a defect in differentiation, rather than altered rates of proliferation or apoptosis. The results presented in this paper are consistent with trBrca1 possessing dominant-negative activity and playing an important role in regulating normal mammary development. They may also have implications for germline carriers of BRCA1 mutations.

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Background and Aim: Patients with gastric carcinomas have a poor prognosis and low survival rates. The aim of the present paper was to characterize cellular and molecular properties to provide insight into aspects of tumor progression in early compared with advanced gastric cancers. Methods: One hundred and nine graded gastric carcinomas (early or advanced stage, undifferentiated or differentiated type) with paired non-cancer tissue were studied to define the correlation between apoptosis (morphology, terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling), cell proliferation (Ki-67 expression, morphology) and expression and localization of two proteins frequently having altered expression in cancers, namely p53 and c-myc. Results: Overall, apoptosis was lower in early stage, differentiated and undifferentiated gastric carcinomas compared with advanced-stage cancers. Cell proliferation was comparatively high in all stages. There was a high level of p53 positivity in all stages. Only the early- and advanced-stage undifferentiated cancers that were p53 positive had a significantly higher level of apoptosis (P< 0.05). Cell proliferation was significantly greater (P < 0.05) only in the early undifferentiated cancers that had either c-myc or p53-positivity. Conclusions: The results indicate that low apoptosis and high cell proliferation combine to drive gastric cancer development. The molecular controls for high cell proliferation of the early stage undifferentiated gastric cancers involve overexpression of both p53 and c-myc. Overexpression of p53 may also control cancer development in that its expression is associated with higher levels of apoptosis in early and late-stage undifferentiated, cancers. (C) 2002 Blackwell Publishing Asia Pty Ltd.