941 resultados para Adult Development
Resumo:
Background: Treacher Collins syndrome (TCS) is an autosomal dominant craniofacial disorder caused by frameshift deletions or duplications in the TCOF1 gene. These mutations cause premature termination codons, which are predicted to lead to mRNA degradation by nonsense mediated mRNA decay (NMD). Haploinsufficiency of the gene product (treacle) during embryonic development is the proposed molecular mechanism underlying TCS. However, it is still unknown if TCOF1 expression levels are decreased in postembryonic human cells. Methods: We have estimated TCOF1 transcript levels through real time PCR in mRNA obtained from leucocytes and mesenchymal cells of TCS patients (n = 23) and controls (n = 18). Mutational screening and analysis of NMD were performed by direct sequencing of gDNA and cDNA, respectively. Results: All the 23 patients had typical clinical features of the syndrome and pathogenic mutations were detected in 19 of them. We demonstrated that the expression level of TCOF1 is 18-31% lower in patients than in controls (p < 0.05), even if we exclude the patients in whom we did not detect the pathogenic mutation. We also observed that the mutant allele is usually less abundant than the wild type one in mesenchymal cells. Conclusions: This is the first study to report decreased expression levels of TCOF1 in TCS adult human cells, but it is still unknown if this finding is associated to any phenotype in adulthood. In addition, as we demonstrated that alleles harboring the pathogenic mutations have lower expression, we herein corroborate the current hypothesis of NMD of the mutant transcript as the explanation for diminished levels of TCOF1 expression. Further, considering that TCOF1 deficiency in adult cells could be associated to pathologic clinical findings, it will be important to verify if TCS patients have an impairment in adult stem cell properties, as this can reduce the efficiency of plastic surgery results during rehabilitation of these patients.
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The in vitro schistosomicidal effects of the essential oil of Ageratum conyzoides L. (Ac-EO) against adult worms of Schistosoma mansoni is reported in this paper. Concerning this activity, Ac-EO was considered to be active, but less effective than the positive control (praziquantel, PZQ) in terms of separation of coupled pairs, mortality, decrease in motor activity, and tegumental alterations. However, Ac-EO caused an interesting dose-dependent reduction in the number of eggs of S. mansoni. Precocene I (74.30%) and (E)-caryophyllene (14.23%) were identified as the two major constituents of Ac-EO. These compounds were tested individually and were found to be much less effective than Ac-EO and PZQ. A mixture of the two major compounds in a ratio similar to that found in the Ac-EO was also less effective than Ac-EO, thus revealing that there are no synergistic effects between these components. These results suggest that the essential oil of A. conyzoides is very promising for the development of new schistosomicidal agents.
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Background: Recent studies have supported the concept of ""fetal programming"" which suggests that during the intrauterine development the fetus may be programmed to develop diseases in adulthood. The possible effects of in utero protein restriction on sexual development of rat male offspring were evaluated in the present study. Methods: Pregnant Wistar rats were divided into two experimental groups: one group treated with standard chow (SC, n = 8, 17% protein) and the other group treated with hypoproteic chow (HC, n = 10, 6% protein) throughout gestation. After gestation the two experimental groups received standard chow. To evaluate the possible late reproductive effects of in utero protein restriction, the male offspring of both groups were assessed at different phases of sexual development: prepubertal (30 days old); peripubertal (60 days old); adult (90 days old). Student's t test and Mann-Whitney test were utilized. Differences were considered significant when p < 0.05. Results: We found that in utero protein restriction reduced the body weight of male pups on the first postnatal day and during the different sexual development phases (prepubertal, peripubertal and adult). During adulthood, Sertoli cell number, sperm motility and sperm counts in the testis and epididymal cauda were also reduced in HC. Furthermore, the numbers of sperm presenting morphological abnormalities and cytoplasmic drop retention were higher in HC. Conclusions: In conclusion, in utero protein restriction, under these experimental conditions, causes growth delay and alters male reproductive-system programming in rats, suggesting impairment of sperm quality in adulthood.
Resumo:
In early development, female embryos (XX) produce twice the transcripts of X-linked genes compared with male embryos (XY). During the course of development, inactivation of the X chromosome equilibrates gene dosage, making the development of female embryos viable. Moreover, the biotechnologies used for producing embryos in vitro seem to work better with male embryos, making it easier for them to reach the blastocyst stage and allow for complete gestation. We investigated the expression of three X-linked genes that are involved in development, XIST, G6PD, and HPRT, and of the transcript interferon-tau, in male and female bovine blastocysts produced by nuclear transfer (NT) and by in vitro fertilization (IVF). Oocytes that had been matured in vitro were enucleated and reconstructed with somatic cells from adult animals at 18 h post-maturation. After fusion (two pulses of 2.25 kv/cm) and chemical activation (5.0 mu M ionomycin for 5 min and 2.0 mM 6-DMAP for 3 h), the oocytesomatic cell units were cultivated in CR2 with a monolayer of granulosa cells at 38.8 degrees C, in a humidified 5% CO(2) atmosphere. IVF embryos were inseminated, after centrifugation in a Percoll gradient, with 2 x 10(6) sperm/mL TALP medium supplemented with BSA and PHE and cultivated under the same conditions as the cloned embryos. We used real-time PCR to analyze the gene expression of individual blastocysts compared to expression of the housekeeping gene, GAPDH. The gene XIST was expressed in female embryos and not in male embryos produced by IVF, though it was expressed at low levels in male embryos produced by NT. Unlike previous reports, we found lower levels of the transcript of G6PD in females than in males, suggesting double silencing or other mechanisms of control of this gene. Female embryos produced by IVF expressed the HPRT gene at a higher level than female embryos produced by NT, suggesting that gene silencing proceeds faster in NT-produced female embryos due to ""inactivation memory"" from the nucleus donor. In conclusion, male and female embryos express different levels of X-chromosome genes and failures of these genes that are essential for development could reduce the viability of females. Nuclear transfer can modify this relation, possibly due to epigenetic memory, leading to frequent failures in nuclear reprogramming.
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The relationship between the level of cell confluence near the plateau phase of growth and blastocyst yield following somatic cell cloning is not well understood. We examined the effect of distinct cell culture confluence levels on in vitro development of cloned bovine embryos. In vitro-matured bovine oocytes were manually bisected and selected by DNA staining. One or two enucleated hemi-cytoplasts were paired and fused with an adult skin somatic cell. Cultured skin cells from an adult Nellore cow harvested at three distinct culture confluence levels (70-80, 80-90, and > 95%) were used for construction of embryos and hemi-embryos. After activation, structures were cultured in vitro as one embryo (1 x 100%) or as aggregates of two hemi-embryos (2 x 50%) per microwell. Fusion, cleavage and blastocyst rates were compared using the chi(2) test. The fusion rate for hemi-embryos (51.4%) was lower than for embryos (67.6%), with no influence of degree of cell confluence. However, blastocyst rates improved linearly (7.0, 17.5, and 29.4%) with increases in cell confluence. We conclude that degree of cell culture confluence significantly influences subsequent embryo development; use of a cell population in high confluence (> 90%) for nuclear transfer significantly improved blastocyst yield after cloning.
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Cell cycle synchronization by serum starvation (SS) induces apoptosis in somatic cells. This side effect of SS is hypothesized to negatively affect the outcome of somatic cell nuclear transfer (SCNT). We determined whether apoptotic fibroblasts affect SCNT yields. Serum-starved, adult, bovine fibroblasts were stained with annexin V-FITC/propidium iodide to allow apoptosis detection by flow cytometry. Positive and negative cells sorted by fluorescence activated cell sorting (FACS) and an unsorted control group were used as nuclear donors for SCNT. Reconstructed embryos were cultured in vitro and transferred to synchronized recipients. Apoptosis had no effect on fusion and cleavage rates; however, it resulted in reductions in blastocyst production and quality measured by apoptotic index. However, reconstructed embryos with apoptotic cells resulted in pregnancy rates similar to that of the control on day 30, and generated one live female calf. In conclusion, we showed that apoptotic cells present in serum-starved cultures negatively affect embryo production after SCNT without compromising full-term development. Further studies will evaluate the ability of the oocyte to reprogram cells in specific phases of apoptosis.
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Allometric growth analysis on chelac dimensions vs. carapace length (CL) was employed to estimate average size at the onset of morphometric maturity (= puberty molt) and sexual dimorphism regarding the pair of chelae in Aegla franca. Males attain morphometric maturity (12.15 mm of CL) at a larger size than females (10.93 mm of CL). After the puberty molt, an additional change in the allometry level regarding chelae dimensions was detected in adult males (average CL = 19.00 mm). As a result, two sequential morphotype groups of adult males, herein designated as morphotype I and morphotype II, were recognized according to the state of development of the pair of claws. We postulate that the second change in this allometry level is related to functional maturity in this sex, based on the following observations: 1) temporal variation in the proportion between the two morphotype groups reveals that morphotype II individuals make up most of adult males in the population at the beginning of the seasonal reproductive period of the species, and 2) morphotype II males show a more robust pair of claws as compared to the predecessor morphotype, which might represent an advantageous trait in reproductive competition. Males and females of Aegla franca are heterochelous with handedness preponderance of the left chela. Claw size is a distinct dimorphic trait in this species, being significantly larger in male specimens.
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AIM: We sought to evaluate the predictive validity of the Waterlow Scale in hospitalized patients. SUBJECTS AND SETTING: The study was conducted at a general private hospital with 220 beds and a mean time of hospitalization of 7.4 days and a mean occupation rate of approximately 80%. Adult patients with a Braden Scale score of 18 or less and a Waterlow Scale score of 16 or more were studied. The sample consisted of 98 patients with a mean age of 71.1 +/- 15.5 years. METHODS: Skin assessment and scoring by using the Waterlow and Braden scales were completed on alternate days. Patients were examined at least 3 times to be considered for analysis. The data were submitted to sensitivity and specificity analysis by using receiver operating characteristic (ROC) curves and positive (+LR) and negative (-LR) likelihood ratios. RESULTS: The cutoff scores were 17, 20, and 20 in the first, second, and third assessment, respectively. Sensitivity was 71.4%, 85.7%, and 85.7% and specificity was 67.0%, 40.7%, and 32.9%, respectively. Analysis of the area under the ROC curve revealed good accuracy (0.64, 95% confidence interval [CI]: 0.35-0.93) only for the cutoff score 17 in the first assessment. The results also showed probabilities of 14%, 10%, and 9% for the development of pressure ulcer when the test results were positive (+LR) and of 3% (-LR) when the test results were negative for the cutoff scores in the first, second, and third assessment, respectively. CONCLUSION: The Waterlow Scale achieved good predictive validity in predicting pressure ulcer in hospitalized patients when a cutoff score of 17 was used in the first assessment.
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Plants synthesize a variety of molecules to defend themselves against an attack by insects. Talisin is a reserve protein from Talisia esculenta seeds, the first to be characterized from the family Sapindaceae. In this study, the insecticidal activity of Talisin was tested by incorporating the reserve protein into an artificial diet fed to the velvetbean caterpillar Anticarsia gemmatalis, the major pest of soybean crops in Brazil. At 1.5% (w/w) of the dietary protein, Talisin affected larval growth, pupal weight, development and mortality, adult fertility and longevity, and produced malformations in pupae and adult insects. Talisin inhibited the trypsin-like activity of larval midgut homogenates. The trypsin activity in Talisin-fed larvae was sensitive to Talisin, indicating that no novel protease-resistant to Talisin was induced in Talisin-fed larvae. Affinity chromatography showed that Talisin bound to midgut proteinases of the insect A. gemmatalis, but was resistant to enzymatic digestion by these larval proteinases. The transformation of genes coding for this reserve protein could be useful for developing insect resistant crops. (C) 2010 Elsevier Inc. All rights reserved.
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This study aimed to evaluate adult emergence and duration of the pupal stage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and emergence of the fruit fly parasitoid, Diachasmimorpha longicaudata (Ashmead), under different moisture conditions in four soil types, using soil water matric potential Pupal stage duration in C capitata was influenced differently for males and females In females, only soil type affected pupal stage duration, which was longer in a clay soil In males, pupal stage duration was individually influenced by moisture and soil type, with a reduction in pupal stage duration in a heavy clay soil and in a sandy clay, with longer duration in the clay soil As allude potential decreased, duration of the pupal stage of C capitata males increased, regardless of soil type C capitata emergence was affected by moisture, regardless of soil type, and was higher in drier soils The emergence of D longicaudata adults was individually influenced by soil type and moisture factors, and the number of emerged D longicaudata adults was three times higher in sandy loam and lower in a heavy clay soil Always, the number of emerged adults was higher at higher moisture conditions C capitata and D longicaudata pupal development was affected by moisture and soil type, which may facilitate pest sampling and allow release areas for the parasitoid to be defined under field conditions.
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Proteinase inhibitors (PI) are present in plant tissues, especially in seeds, and act as a defense mechanism against herbivores and pathogens. Serine PI from soybean such as Bowman-Birk (BBPI) and Kunitz have been used to enhance resistance of sugarcane varieties to the sugarcane borer Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae), the major pest of this crop. The use of these genetically-modified plants (GM) expressing PI requires knowledge of its sustainability and environmental safety, determining the stability of the introduced characteristic and its effects on non-target organisms. The objective of this study was to evaluate direct effects of ingestion of semi-purified and purified soybean PI and GM sugarcane plants on the soil-dwelling mite Scheloribates praeincisus (Berlese) (Acari: Oribatida). This mite is abundant in agricultural soils and participates in the process of organic matter decomposition; for this reason it will be exposed to PI by feeding on GM plant debris. Eggs of S. praeincisus were isolated and after larvae emerged, immatures were fed milled sugarcane leaves added to semi-purified or purified PI (Kunitz and BBPI) or immatures were fed GM sugarcane varieties expressing Kunitz and BBPI type PI or the untransformed near isogenic parental line variety as a control. Developmental time (larva-adult) and survival of S. praeincisus was evaluated. Neither Kunitz nor BBPI affected S. praeincisus survival. On the other hand, ingestion of semi-purified and purified Kunitz inhibitor diminished duration of S. praeincisus immature stages. Ingestion of GM senescent leaves did not have an effect on S. praeincisus immature developmental time and survival, compared to ingestion of leaves from the isogenic parental plants. These results indicate that cultivation of these transgenic sugarcane plants is safe for the non-target species S. praeincisus.
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The ecological and economic importance of oleoresin produced by Copaifera langsdorffii is well established. This study aims to investigate the ontogeny, anatomy and ultrastructure of the internal glands of C. langsdorffii during plant development. Samples were processed for light and electron microscopy and a specific technique was applied to impregnate endomembranes. Internal secretory glands were observed in the hypocotyl, epicotyl and eophylls of seedlings, and in the primary stem, pulvinus, petiole, rachis and leaf blade of adult plants. Canals and cavities show differential distribution. They arise from ground meristem cells, and the lumen is first formed by schizogenesis followed by later schizolysigenous development. The dense cytoplasm of epithelial cells shows mitochondria, plastids without thylakoids, polyribosomes and endoplasmic reticulum. A periplastidial reticulum was also observed. Secretion is released by eccrine, granulocrine and holocrine processes. Lipophilic and hydrophilic compounds were histochemically detected in both canals and cavities, whereas resin was detected only in canals. The presence of these substances has been associated with plants` defences against dehydration, as well as against attacks from herbivores and pathogens, from seedling stage onwards. (C) 2011 Elsevier GmbH. All rights reserved.
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Age is a critical determinant of an adult female mosquito's ability to transmit a range of human pathogens. Despite its central importance, relatively few methods exist with which to accurately determine chronological age of field-caught mosquitoes. This fact is a major constraint on our ability to fully understand the relative importance of vector longevity to disease transmission in different ecological contexts. It also limits our ability to evaluate novel disease control strategies that specifically target mosquito longevity. We report the development of a transcriptional profiling approach to determine age of adult female Aedes aegypti under field conditions. We demonstrate that this approach surpasses current cuticular hydrocarbon methods for both accuracy of predicted age as well as the upper limits at which age can be reliably predicted. The method is based on genes that display age-dependent expression in a range of dipteran insects and, as such, is likely to be broadly applicable to other disease vectors.
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Increasing evidence from human epidemiological studies suggests that poor growth before birth is associated with postnatal growth retardation and the development of cardiovascular disease in adulthood. We have shown previously that nutritional deprivation in the pregnant rat leads to intrauterine growth retardation (IUGR), postnatal growth failure, changes in the endocrine parameters of the somatotrophic axis, and to increased blood pressure in later life. In the present study, we investigated whether administration of insulin-like growth factor-I (IGF-I) or bovine growth hormone (GH) during pregnancy could prevent IUGR and/or alter long-term outcome. Dams h-om day 1 of pregnancy throughout gestation received a diet of nd libitum available food or a restricted dietary intake of 30% of ad libitum fed dams. From day 10 of gestation, dams were treated for 10 days with three times daily subcutaneous injections of saline (100 mu l), IGF-I (2 mu g/g body weight) or GH (2 mu g/g body weight). Maternal weight gain was significantly increased (P
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Primary olfactory neurons project their axons to the olfactory bulb, where they terminate in discrete loci called glomeruli. All neurons expressing the same odorant receptor appear to terminate in a few glomeruli in each olfactory bulb. In the P2-IRES-tau-LacZ line of transgenic mice, LacZ is expressed in the perikarya and axons of primary olfactory neurons that express the P2 odorant receptor. In the present study, we examined the developmental appearance of P2 neurons, the topographical targeting of P2 axons, as well as the formation of P2 glomeruli in the olfactory bulb. P2 axons were first detected in the olfactory nerve fiber layer at embryonic day 14.5 (E14.5), and by E15.5 these axons terminated in a broad locus in the presumptive glomerular layer. During the next 5 embryonic days, the elongated cluster of axons developed into discrete glomerulus-like structures. In many cases, glomeruli appeared as pairs, which were initially connected by a fascicle of P2 axons. This connection was lost by postnatal day 7.5, and double glomeruli at the same locus were observed in 85% of adult animals. During the early postnatal period, there was considerable mistargeting of P2 axons. In some cases P2 axons entered inappropriate glomeruli or continued to grow past the glomerular layer into the deeper layers of the olfactory bulb. These aberrant axons were not observed in adult animals. These results indicate that olfactory axons exhibit errors while converging onto a specific glomerulus and suggest that guidance cues may be diffusely distributed at target sites in the olfactory bulb.