964 resultados para Somatic embryos
Resumo:
Cells of the mononuclear phagocyte lineage possess receptors for macrophage colony-stimulating factor (CSF-1) encoded by the c-fms protooncogene and respond to CSF-1 with increased survival, growth, differentiation, and reversible changes in function. The c-fms gene is itself a macrophage differentiation marker. In whole mount analyses of mRNA expression in embryos, c-fms is expressed at very high levels on placental trophoblasts. It is detectable on individual cells in the yolk sac around 8.5 to 9 days postcoitus, appears on isolated cells in the head of the embryo around 9.5 dpc, and appears on numerous cells throughout the embryo by day 10.5. The extent of c-fms expression is much greater than for other macrophage-specific genes including lysozyme and a macrophage-specific protein tyrosine phosphatase. Our studies of the cis-acting elements of the c-fms promoter have indicated a key role for collaboration between the macrophage-specific transcription factor, Pu.1, which functions in determining the site of transcription initiation, and other members of the Ets transcription factor family. This is emerging as a common pattern in macrophage-specific promoters. We have shown that two PU box elements alone can function as a macrophage-specific promoter. The activity of both the artifical promoter and the c-fms promoter is activated synergistically by coexpression of Pu.1 and another Ets factor, c-Ets-2. A 3.5kb c-fms exon 2 promoter (but not the 300bp proximal promoter) is also active in a wide diversity of tumor cell lines. The interesting exception is the melanoma cell line K1735, in which the promoter is completely shut down and expression of c-fms causes growth arrest and cell death. The activity of the exon 2 promoter in these nonmacrophages is at least as serum responsive as the classic serum-responsive promoter of the c-fos gene. It is further inducible in nonmacrophages by coexpression of the c-fms product. Unlike other CSF-1/c-fms-responsive promoters, the c-fms promoter is not responsive to activated Ras even when c-Ets-2 is coexpressed. In most lines, production of full length c-fms is prevented by a downstream intronic terminator, but in Lewis lung carcinoma, read-through does occur, and expression of both c-fms and other macrophage-specific genes such as lysozyme and urokinase becomes detectable in conditions of serum deprivation. (C) 1997 Wiley-Liss, Inc.
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This study analyzes the relationship between extracellular purines and pain perception in humans. Cerebrospinal fluid (CSF) levels of purines and their metabolites were compared between patients displaying acute and/or chronic pain syndromes and control subjects. The CSF levels of IMP, inosine, guanosine and uric acid were significantly increased in the chronic pain group and correlated with pain severity (P<0.05). Patients displaying both chronic and acute pain presented similar changes in the CSF purines concentration (P<0.05). However, in the acute pain group, only CSF inosine and uric acid levels were significantly increased (P<0.05). These findings suggest that purines, in special inosine, guanosine and uric acid, are associated with the spinal mechanisms underlying nociception. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
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Purpose: We evaluated the somatic and autonomic innervation of the pelvic floor and rhabdosphincter before and after nerve sparing radical retropubic prostatectomy using neurophysiological tests and correlated findings with clinical parameters and urinary continence. Materials and Methods: From February 2003 to October 2005, 46 patients with prostate cancer were enrolled in a controlled, prospective study. Patients were evaluated before and 6 months after nerve sparing radical retropubic prostatectomy using the UCLA-PCI urinary function domain and neurophysiological tests, including somatosensory evoked potential, and the pudendo-urethral, pudendo-anal and urethro-anal reflexes. Clinical parameters and urinary continence were correlated with afferent and efferent innervation of the membranous urethra and pelvic floor. We used strict criteria to define urinary continence as complete dryness with no leakage at all, not requiring any pads or diapers and with a UCLA-PCI score of 500. Patients with a sporadic drop of leakage, requiring up to 1 pad daily, were defined as having occasional urinary leakage. Results: Two patients were excluded from study due to urethral stricture postoperatively. We evaluated 44 patients within 6 months after surgery. The pudendo-anal and pudendo-urethral reflexes were unchanged postoperatively (p = 0.93 and 0.09, respectively), demonstrating that afferent and efferent pudendal innervation to this pelvic region was not affected by the surgery. Autonomic afferent denervation of the membranous urethral mucosa was found in 34 patients (77.3%), as demonstrated by a postoperative increase in the urethro-anal reflex sensory threshold and urethro-anal reflex latency (p<0.001 and 0.0007, respectively). Six of the 44 patients used pads. One patient with more severe leakage required 3 pads daily and 23 showed urinary leakage, including 5 who needed 1 pad per day and 18 who did not wear pads. Afferent autonomic denervation at the membranous urethral mucosa was found in 91.7% of patients with urinary leakage. Of 10 patients with preserved urethro-anal reflex latency 80% were continent. Conclusions: Sensory and motor pudendal innervation to this specific pelvic region did not change after nerve sparing radical retropubic prostatectomy. Significant autonomic afferent denervation of the membranous urethral mucosa was present in most patients postoperatively. Impaired membranous urethral sensitivity seemed to be associated with urinary incontinence, particularly in patients with occasional urinary leakage. Damage to the afferent autonomic innervation may have a role in the continence mechanism after nerve sparing radical retropubic prostatectomy.
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We have studied gene expression during ascidian embryonic development using the technique of differential display and isolated partial cDNA sequences of 12 genes. Developmental regulation of these genes has been confirmed by northern hybridization analysis. Further cDNA cloning and sequence analysis of an mRNA that is present during gastrulation, neurulation and tailbud formation reveals that it encodes a novel serine protease containing a single kringle motif and catalytic domain. The spatial expression of this gene, designated Hmserp1, is restricted to precursor cells of the epidermis. The structure and expression of Hmsery1 is discussed in relation to possible functions during development.
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Previous functional magnetic resonance imaging (fMRI) studies examined neural activity responses to emotive stimuli in healthy individuals after acute/subacute administration of antidepressants. We now report the effects of repeated use of the antidepressant clomipramine on fMRI data acquired during presentation of emotion-provoking and neutral stimuli on healthy volunteers. A total of 12 volunteers were evaluated with fMRI after receiving low doses of clomipramine for 4 weeks and again after 4 weeks of washout. Fear-, happiness-, anger-provoking and neutral pictures from the International Affective Picture System (IAPS) were used. Data analysis was performed with statistical parametric mapping (P < 0.05). Paired t-test comparisons for each condition between medicated and unmedicated states showed, to negative valence paradigms, decrease in brain activity in the amygdala when participants were medicated. We also demonstrated, across both positive and negative valence paradigms, consistent decreases in brain activity in the medicated state in the anterior cingulate gyrus and insula. This is the first report of modulatory effects of repeated antidepressant use on the central representation of somatic states in response to emotions of both negative and positive valences in healthy individuals. Also, our results corroborate findings of antidepressant-induced temporolimbic activity changes to emotion-provoking stimuli obtained in studies of subjects treated acutely with such agents.
Resumo:
We have investigated molecular mechanisms of the embryonic development of an ascidian, a primitive chordate which shares features of both invertebrates and vertebrates, with a view to identifying genes involved in development and metamorphosis, We isolated 12 partial cDNA sequences which were expressed in a stage-specific manner using differential display, We report here the isolation of a full-length cDNA sequence for one of these genes which was specifically expressed during the tailbud and larval stages of ascidian development, This cDNA, 1213 bp in length, is predicted to encode a protein of 337 amino acids containing four epidermal growth factor (EGF)-like repeats and three novel cysteine-rich repeats, Characterization of its spatial expression pattern by in situ hybridisation in late tailbud and larval embryos demonstrated strong expression localised throughout the papillae and anteriormost trunk and weaker expression in the epidermis of the remainder of the embryo, As recent evidence indicates that the signal for metamorphosis originates in the anterior trunk region, these results suggest that this gene may have a role in signalling the initiation of metamorphosis. (C) 1997 Wiley-Liss, Inc.
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Lineage-survival oncogenes are activated by somatic DNA alterations in cancers arising from the cell lineages in which these genes play a role in normal development(1,2). Here we show that a peak of genomic amplification on chromosome 3q26.33 found in squamous cell carcinomas (SCCs) of the lung and esophagus contains the transcription factor gene SOX2, which is mutated in hereditary human esophageal malformations(3), is necessary for normal esophageal squamous development(4), promotes differentiation and proliferation of basal tracheal cells(5) and cooperates in induction of pluripotent stem cells(6-8). SOX2 expression is required for proliferation and anchorage-independent growth of lung and esophageal cell lines, as shown by RNA interference experiments. Furthermore, ectopic expression of SOX2 here cooperated with FOXE1 or FGFR2 to transform immortalized tracheobronchial epithelial cells. SOX2-driven tumors show expression of markers of both squamous differentiation and pluripotency. These characteristics identify SOX2 as a lineage-survival oncogene in lung and esophageal SCC.
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Background: The high prevalence of subjective memory impairment (SMI) in the elderly living in developed countries may be partly dependent on greater demand placed on them by new technologies. As part of a comprehensive study on cognitive impairment in a population living in the Amazon rainforest, we evaluated the prevalence of SMI and investigated the features associated with it. Methods: We evaluated 163 subjects (82 females) with a mean age of 62.3 years (50-94 years), 110 of whom were illiterate, using the answer to a single question ""Do you have memory problems?"" to classify them into groups with or without SMI. The assessment involved application of the Mini-mental State Examination (MMSE), delayed recall from the Brief Cognitive Battery designed for the evaluation of low educated and illiterate individuals, the Patient Questionnaire (PQ) of the Primary Care Evaluation of Mental Disorders (PRIME-MD), and the Happiness Analogical Scale. Results: A very high prevalence of SMI (70%) was observed, exceeding rates reported by similar studies conducted in developed countries. SMI was more frequent in women, whereas age and education did not impact on prevalence. Subjects with SMI had significantly more somatic and psychiatric symptoms on the PQ, as well as lower means on the MMSE, but not on the delayed recall test. Multiple logistic regressions showed that the most important factor associated with the presence of SMI was a high score on the PQ (OR: 3.84, p = 0.011). Conclusion: Psychological and somatic symptoms may be the principal cause of SMI in this population.
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Medulloblastoma (MB) is the most common malignant brain tumor of children. To identify the genetic alterations in this tumor type, we searched for copy number alterations using high-density microarrays and sequenced all known protein-coding genes and microRNA genes using Sanger sequencing in a set of 22 MBs. We found that, on average, each tumor had 11 gene alterations, fewer by a factor of 5 to 10 than in the adult solid tumors that have been sequenced to date. In addition to alterations in the Hedgehog and Wnt pathways, our analysis led to the discovery of genes not previously known to be altered in MBs. Most notably, inactivating mutations of the histone-lysine N-methyltransferase genes MLL2 or MLL3 were identified in 16% of MB patients. These results demonstrate key differences between the genetic landscapes of adult and childhood cancers, highlight dysregulation of developmental pathways as an important mechanism underlying MBs, and identify a role for a specific type of histone methylation in human tumorigenesis.
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Objective: To evaluate influences of vitrification and warming of metaphase II (MII) mouse oocytes on survival, spindle dynamics. spindle morphology, and chromatin alignment on metaphase plates. Design: Experimental animal Study. Setting: University animal laboratory. Animal(s): Eight-week-old B6D2F1 mice. Intervention(s): Denuded MII oocytes were used fresh (control), exposed to vitrification/warming solutions (Sol Expos), or vitrified and warmed (Vitr). Main Outcome Measure(s): Oocyte recovery and survival after warming and the influence of solution exposure and cryopreservation on spindle dynamics and chromatin alignment. Result(s): Cryopreservation of two or 10 oocytes per straw resulted in recovery (100% +/- 0% and 95% +/- 4%, respectively; mean SE) and survival (95% 2% and 98% 2%, respectively). Immediately after warming (Vitr), significantly fewer oocytes assessed with immunocytochemistry contained spindles, compared with control and Sol Expos. When oocytes were placed into a 3 degrees 7C environment for 2 hours after exposure or warming, the ability to recognize spindles by immunocytochemistry was not significantly different between groups. Using live-cell time-lapse imaging with LC-Polscope, similar time-dependent spindle formation dynamics were observed. At 2 hours after collection or treatment, spindle morphology and length were not significantly different between the groups, nor was the incidence of aberrant alignment of chromatin on metaphase plates. Conclusion(s): Immediately after warming of vitrified MII oocytes, beta-tubulin is depolymerized and chromatin remains condensed on the metaphase plate. Within a 2-hour period, beta-tubulin repolymerizes, forming morphologically normal metaphase spindles with properly aligned chromatin.
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Although the number of genes known to be associated with bovine spermatogenesis has increased in the past few years, regulation of this biological process remains poorly understood. Therefore, discovery of new male fertility genetic markers is of great value for assisted selection in commercially important cattle breeds, e.g., Nelore, that have delayed reproductive maturation and low fertility rates. The objective of the present study was to identify sequences associated with spermatogenesis that could be used as fertility markers. With RT-PCR, the following five transcripts preferentially expressed in adult testis were detected: TET(656) detected only in adult testis; TET(868) and TET(515) expressed preferentially in adult testis but also detected in fetal gonads of both sexes; and TET(456) and TET(262). expressed primarily in the testis, but also present in very low amounts in somatic tissues. Based on their homologies and expression profiles, we inferred that they had putative roles in spermatogenesis. Detection of sequences differentially expressed in testis, ovary, or both, was a useful approach for identifying new genes related to bovine spermatogenesis. The data reported here contributed to discovery of gene pathways involved in bovine spermatogenesis, with potential for prediction of fertility. (C) 2011 Elsevier Inc. All rights reserved.
Resumo:
Contents Sex pre-selection of bovine offsprings has commercial relevance for cattle breeders and several methods have been used for embryo sex determination. Polymerase chain reaction (PCR) has proven to be a reliable procedure for accomplishing embryo sexing. To date, most of the PCR-specific primers are derived from the few single-copy Y-chromosome-specific gene sequences already identified in bovines. Their detection demands higher amounts of embryonic genomic material or a nested amplification reaction. In order to circumvent this, limitation we searched for new male-specific sequences potentially useful in embryo sexing using random amplified polymorphic DNA (RAPD) analysis. Random amplified polymorphic DNA (RAPD) assay reproducibility problems can be overcome by its conversion into Sequence Characterized Amplified Region (SCAR) markers. In this work, we describe the identification of two bovine male-specific markers (OPC16(323) and OPF10(1168)) by means of RAPD. These markers were successfully converted into SCARs (OPC16(726) and OPF10(984)) using two pairs of specific primers.Furthermore, inverse PCR (iPCR) methodology was successfully applied to elongate OPC16(323) marker in 159% (from 323 to 837 bp). Both markers are shown to be highly conserved (similarity >= 95%) among bovine zebu and taurine cattle; OPC16(323) is also highly similar to a bubaline Y-chromosome-specific sequence. The primers derived from the two Y-chromosome-specific conserved sequences described in this article showed 100% accuracy when used for identifying male and female bovine genomic DNA, thereby proving their potential usefulness for bovine embryo sexing.
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Objective: To compare the variability of patterns of depressive symptoms between two consecutive depressive episodes in patients with bipolar disorder type I. Methods: Review of prospectively collected data from 136 subjects of an out-patient bipolar unit from 1997 to 2007. Binomial statistics was used for the analysis of Hamilton Depression Rating Scale (HDRS)-31 items of the first and second episodes, and the correlation of the HDRS-31 item scores of both episodes was determined using the Spearman coefficient. Results: Ten depressive symptoms showed a significant correlation between index and subsequent episodes: psychological anxiety, somatic anxiety, somatic symptoms, diurnal variation, paranoid symptoms, obsessive and compulsive symptoms, hypersomnia, loss of appetite and helplessness. Only four symptoms were stable in both statistical tests: paranoid symptoms, obsessive-compulsive symptoms, loss of appetite and hypersomnia. Conclusions: Paranoid and obsessive-compulsive symptoms, loss of appetite and hypersomnia tended to be found in successive episodes. However, the moderate correlations of the symptoms across two depressive recurrences suggested that clinical presentations in bipolar depression may not be predicted by symptom profiles presented in previous episodes.
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Introduction. The diagnosis and the treatment of transsexualism, particularly during adolescence, generate considerable discussion among specialists. Many health and legal professionals have not yet reached a strong consensus on medical treatment for juvenile transsexuals. Hormonal therapy cannot only represent a medical procedure to adjust the somatic sex to the psychological gender, but can also be a reasonable means of preventing some juvenile transsexuals from engaging in undesirable and risky behavior. Aim. To report the cases of two transsexual adolescents who resorted to prostitution to afford hormonal medications when treatment was denied because of age criteria. Results. Hormonal medications were not recommended by the endocrinology staff because specific laws regulating this medical procedure for juvenile transsexuals in Brazil are lacking. In response, these adolescents chose to use illegally obtained sex hormones to treat themselves. Conclusions. We propose ""harm reduction"" as a means of coping with this dilemma in some cases. Baltieri DA, Cortez FCP, and de Andrade AG. Ethical conflicts over the management of transsexual adolescents-report of two cases. J Sex Med 2009;6:3214-3220.
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Objective: We correlated dietary profile and markers of visceral and somatic obesities in nonalcoholic fatty liver disease. Methods: Patients with histologically proven fatty infiltration of the liver (n = 25, 52 +/- 11 y of age, 64% women) underwent abdominal computed tomography, bioelectrical impedance, and anthropometric measurements. Insulin resistance was evaluated (homeostasis model assessment) and dietary intake of macronutrients was estimated by 24-h recall. Main outcome measurements were correlation of carbohydrate and fat ingestion with liver histology. Results: Metabolic syndrome was present in 72% of the population, and increased waist circumference and low high-density lipoprotein cholesterol occurred in 66%. Total body fat (bioimpedance) and dietary intake of lipids were higher in patients with non-alcoholic steatohepatitis (P < 0.05), but not in diabetic subjects who exhibited more steatosis than non-alcoholic steatohepatitis. Waist circumference exhibited a good correlation with homeostasis model assessment, total energy intake, and ingestion of specific fatty acids. Body mass index correlated well with somatic and visceral adiposities. Conclusion: Energy intake and visceral adiposity were predisposing factors for fatty liver disease. Lipid input correlated with non-alcoholic steatohepatitis in the entire group and after stratification for diabetes. These findings suggest that lipid intake may play a greater role in non-alcoholic steatohepatitis than hitherto suspected. (C) 2008 Elsevier Inc. All rights reserved.