32 resultados para Stars: early-type
Resumo:
A new gymnosperm taxon from the Lower Cretaceous (upper Aptian to possibly lower Albian) Crato Formation of Brazil, Duartenia araripensis gen. nov. et sp. nov. is described. The most prominent specimen, a branch with attached lateral branches of higher orders exhibits a distinct anisotomous branching pattern. The very dense wood is composed of tracheids with spaced and partly contiguous uniseriate pits and low rays with one pit per cross-field (mixed protopinaceous type). When foliage is not abraded, Duartenia exhibits coriacious Brachyphyllum-type leaves. Duartenia may be linked to cheirolepid conifers, however, the systematic affinity remains uncertain. The dense wood, characteristic growth pattern and thick, scale like, trichome bearing leaves may be related to ecological conditions that reflect a seasonally dry climate.
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Many cell types have no known functional attributes. In the bladder and prostate, basal epithelial and stromal cells appear similar in cytomorphology and share several cell surface markers. Their total gene expression (transcriptome) should provide a clear measure of the extent to which they are alike functionally. Since urologic stromal cells are known to mediate organ-specific tissue formation, these cells in cancers might exhibit aberrant gene expression affecting their function. For transcriptomes, cluster designation (CD) antigens have been identified for cell sorting. The sorted cell populations can be analyzed by DNA microarrays. Various bladder cell types have unique complements of CD molecules. CD9(+) urothelial, CD104(+) basal and CD13(+) stromal cells of the lamina propria were therefore analyzed, as were CD9(+) cancer and CD13(+) cancer-associated stromal cells. The transcriptome datasets were compared by principal components analysis for relatedness between cell types; those with similarity in gene expression indicated similar function. Although bladder and prostate basal cells shared CD markers such as CD104, CD44 and CD49f, they differed in overall gene expression. Basal cells also lacked stem cell gene expression. The bladder luminal and stromal transcriptomes were distinct from their prostate counterparts. In bladder cancer, not only the urothelial but also the stromal cells showed gene expression alteration. The cancer process in both might thus involve defective stromal signaling. These cell-type transcriptomes provide a means to monitor in vitro models in which various CD-isolated cell types can be combined to study bladder differentiation and bladder tumor development based on cell-cell interaction.
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Chronic kidney diseasemineral bone disorder (CKD-MBD) is defined by abnormalities in mineral and hormone metabolism, bone histomorphometric changes, and/or the presence of soft-tissue calcification. Emerging evidence suggests that features of CKD-MBD may occur early in disease progression and are associated with changes in osteocyte function. To identify early changes in bone, we utilized the jck mouse, a genetic model of polycystic kidney disease that exhibits progressive renal disease. At 6 weeks of age, jck mice have normal renal function and no evidence of bone disease but exhibit continual decline in renal function and death by 20 weeks of age, when approximately 40% to 60% of them have vascular calcification. Temporal changes in serum parameters were identified in jck relative to wild-type mice from 6 through 18 weeks of age and were subsequently shown to largely mirror serum changes commonly associated with clinical CKD-MBD. Bone histomorphometry revealed progressive changes associated with increased osteoclast activity and elevated bone formation relative to wild-type mice. To capture the early molecular and cellular events in the progression of CKD-MBD we examined cell-specific pathways associated with bone remodeling at the protein and/or gene expression level. Importantly, a steady increase in the number of cells expressing phosphor-Ser33/37-beta-catenin was observed both in mouse and human bones. Overall repression of Wnt/beta-catenin signaling within osteocytes occurred in conjunction with increased expression of Wnt antagonists (SOST and sFRP4) and genes associated with osteoclast activity, including receptor activator of NF-?B ligand (RANKL). The resulting increase in the RANKL/osteoprotegerin (OPG) ratio correlated with increased osteoclast activity. In late-stage disease, an apparent repression of genes associated with osteoblast function was observed. These data confirm that jck mice develop progressive biochemical changes in CKD-MBD and suggest that repression of the Wnt/beta-catenin pathway is involved in the pathogenesis of renal osteodystrophy. (C) 2012 American Society for Bone and Mineral Research.
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Background. The long control region (LCR) of human papillomavirus (HPV) regulates early gene transcription by interaction with several viral and cellular transcription factors (TFs). Methods. To identify novel TFs that could influence early expression of HPV type 18 (HPV-18) and HPV type 16 (HPV-16), a high-throughput transfection array was used. Results. Among the 704 TFs tested, 28 activated and 36 inhibited the LCR of HPV-18 by more than 2-fold. For validation, C33 cells were cotransfected with increasing amounts of selected TF expression plasmids in addition to LCR-luciferase vectors of different molecular variants of HPV-18 and HPV-16. Among the TFs identified, only GATA3, FOXA1, and MYC have putative binding sites within the LCR sequence, as indicated using the TRANSFAC database. Furthermore, we demonstrated FOXA1 and MYC in vivo binding to the LCR of both HPV types using chromatin immunoprecipitation assay. Conclusions. We identified new TFs implicated in the regulation of the LCR of HPV-18 and HPV-16. Many of these factors are mutated in cancer or are putative cancer biomarkers and could potentially be involved in the regulation of HPV early gene expression.
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The Dipteran a native Brazilian insect that has become a valuable model system for developmental biology research because it provides an interesting opportunity to study a different type of insect oogenesis. Sequences from a cDNA library that was constructed with poly A + RNA from the ovaries of larvae at different ages were analyzed. Molecular characterization confirmed interesting findings, such as the presence of . The gene encodes a conserved RNA-binding protein that is required during early development for the maintenance and division of the primordial germ cells of Diptera. plays an important role in specifying the posterior regions of insect embryos and is important for abdomen formation. In the present work, we showed the spatial and temporal expression profiles of this important gene, which is involved in oogenesis and early development. Data mining techniques were used to obtain the complete sequence of . Bioinformatic tools were used to determine the following: (1) the secondary structure of the 3'-untranslated region of the mRNA, (2) the encoded protein of the isolated gene, (3) the conserved zinc-finger domains of the Nanos protein, and (4) phylogenetic analyses. Furthermore, RNA in situ hybridization and immunolocalization were used to determine mRNA and protein expression in the tissues that were studied and to define as a germ cell molecular marker.
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Background. The intrafamilial dynamics of endemic infection with human herpesvirus type 8 (HHV-8) in Amerindian populations is unknown. Methods. Serum samples were obtained from 517 Amerindians and tested for HHV-8 anti-latent nuclear antigen (anti-LANA) and antilytic antibodies by immunofluorescence assays. Logistic regression and mixed logistic models were used to estimate the odds of being HHV-8 seropositive among intrafamilial pairs. Results. HHV-8 seroprevalence by either assay was 75.4% (95% confidence interval [CI]: 71.5%-79.1%), and it was age-dependent (P-trend<.001). Familial dependence in HHV-8 seroprevalence by either assay was found between mother-offspring (odds ratio [OR], 5.44; 95% CI: 1.62-18.28) and siblings aged >= 10 years (OR 4.42, 95% CI: 1.70-11.45) or siblings in close age range (<5 years difference) (OR 3.37, 95% CI: 1.21-9.40), or in families with large (>4) number of siblings (OR, 3.20, 95% CI: 1.33-7.67). In separate analyses by serological assay, there was strong dependence in mother-offspring (OR 8.94, 95% CI: 2.94-27.23) and sibling pairs aged >= 10 years (OR, 11.91, 95% CI: 2.23-63.64) measured by LANA but not lytic antibodies. Conclusions. This pattern of familial dependence suggests that, in this endemic population, HHV-8 transmission mainly occurs from mother to offspring and between close siblings during early childhood, probably via saliva. The mother to offspring dependence was derived chiefly from anti-LANA antibodies.
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Background: The purpose of this study was to evaluate the effect of the duodenal-jejunal bypass liner (DJBL), a 60-cm, impermeable fluoropolymer liner anchored in the duodenum to create a duodenal-jejunal bypass, on metabolic parameters in obese subjects with type 2 diabetes. Methods: Twenty-two subjects (mean age, 46.2 +/- 10.5 years) with type 2 diabetes and a body mass index between 40 and 60 kg/m(2) (mean body mass index, 44.8 +/- 7.4 kg/m(2)) were enrolled in this 52-week, prospective, open-label clinical trial. Endoscopic device implantation was performed with the patient under general anesthesia, and the subjects were examined periodically during the next 52 weeks. Primary end points included changes in fasting blood glucose and insulin levels and changes in hemoglobin A1c (HbA1c). The DJBL was removed endoscopically at the end of the study. Results: Thirteen subjects completed the 52-week study, and the mean duration of the implant period for all subjects was 41.9 +/- 3.2 weeks. Reasons for early removal of the device included device migration (n = 3), gastrointestinal bleeding (n = 1), abdominal pain (n = 2), principal investigator request (n = 2), and discovery of an unrelated malignancy (n = 1). Using last observation carried forward, statistically significant reductions in fasting blood glucose (-30.3 +/- 10.2 mg/dL), fasting insulin (-7.3 +/- 2.6 mu U/mL), and HbA1c (-2.1 +/- 0.3%) were observed. At the end of the study, 16 of the 22 subjects had an HbA1c < 7% compared with only one of 22 at baseline. Upper abdominal pain (n = 11), back pain (n = 5), nausea (n = 7), and vomiting (n = 7) were the most common device-related adverse events. Conclusions: The DJBL improves glycemic status in obese subjects with diabetes and therefore represents a nonsurgical, reversible alternative to bariatric surgery.
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We compared E6/E7 protein properties of three different HPV-16 variants: AA. E-P and E-350G. Primary human foreskin keratinocytes (PHFK) were transduced with HPV-16 E6 and E7 and evaluated for proliferation and ability to grow in soft agar. E-P infected keratinocytes presented the lowest efficiency in colony formation. AA and E-350G keratinocytes attained higher capacity for in vitro transformation. We observed similar degradation of TP53 among HPV-16 variants. Furthermore, we accessed the expression profile in early (p5) and late passage (p30) transduced cells of 84 genes commonly involved in carcinogenesis. Most differences could be attributed to HPV-16 E6/E7 expression. In particular, we detected different expression of ITGA2 and CHEK2 in keratinocytes infected with AA and AA/E-350G late passage cells, respectively, and higher expression of MAP2K1 in E-350G transduced keratinocytes. Our results indicate differences among HPV-16 variants that could explain, at least in part, differences in oncogenic potential attributed to these variants. (C) 2012 Elsevier Inc. All rights reserved.
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The innate and adaptive immune responses in neonates are usually functionally impaired when compared with their adult counterparts. The qualitative and quantitative differences in the neonatal immune response put them at risk for the development of bacterial and viral infections, resulting in increased mortality. Newborns often exhibit decreased production of Th1-polarizing cytokines and are biased toward Th2-type responses. Studies aimed at understanding the plasticity of the immune response in the neonatal and early infant periods or that seek to improve neonatal innate immune function with adjuvants or special formulations are crucial for preventing the infectious disease burden in this susceptible group. Considerable studies focused on identifying potential immunomodulatory therapies have been performed in murine models. This article highlights the strategies used in the emerging field of immunomodulation in bacterial and viral pathogens, focusing on preclinical studies carried out in animal models with particular emphasis on neonatal-specific immune deficits.
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Abstract Background The use of stem cells to treat type 1 diabetes mellitus has been proposed for many years, both to downregulate the immune system and to provide β cell regeneration. Conclusion High dose immunosuppression followed by autologous hematopoietic stem cell transplantation is able to induce complete remission (insulin independence) in most patients with early onset type 1 diabetes mellitus.
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Overweight and obesity in youth is a worldwide public health problem. Overweight and obesity in childhood and adolescents have a substantial effect upon many systems, resulting in clinical conditions such as metabolic syndrome, early atherosclerosis, dyslipidemia, hypertension and type 2 diabetes (T2D). Obesity and the type of body fat distribution are still the core aspects of insulin resistance and seem to be the physiopathologic links common to metabolic syndrome, cardiovascular disease and T2D. The earlier the appearance of the clustering of risk factors and the higher the time of exposure, the greater will be the chance of developing coronary disease with a more severe endpoint. The age when the event may occur seems to be related to the presence and aggregation of risk factors throughout life.
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Abstract Introduction In acute lung injury (ALI), elevation of procollagen type III (PC III) occurs early and has an adverse impact on outcome. We examined whether different high-inflation strategies of mechanical ventilation (MV) in oleic acid (OA) ALI alter regional expression of PC III. Methods We designed an experimental, randomized, and controlled protocol in which rats were allocated to two control groups (no injury, recruited [alveolar recruitment maneuver after tracheotomy without MV; n = 4 rats] and control [n = 5 rats]) or four injured groups (one exposed to OA only [n = 10 rats] and three OA-injured and ventilated). The three OA-injured groups were ventilated for 1 hour according to the following strategies: LVHP-S (low volume-high positive end-expiratory pressure [PEEP], supine; n = 10 rats, tidal volume [VT] = 8 ml/kg, PEEP = 12 cm H2O), HVLP-S (high volume-low PEEP, supine; n = 10 rats, VT = 20 ml/kg, PEEP = 5 cm H2O), and HVLP-P (high volume-low PEEP, prone; n = 10 rats). Northern blot analysis for PC III and interleukin-1-beta (IL-1β) and polymorphonuclear infiltration index (PMI) counting were performed in nondependent and dependent regions. Regional differences between groups were assessed by two-way analysis of variance after logarithmic transformation and post hoc tests. Results A significant interaction for group and region effects was observed for PC III (p = 0.012) with higher expression in the nondependent region for HVLP-S and LVHP-S, intermediate for OA and HVLP-P, and lower for control (group effect, p < 0.00001, partial η2 = 0.767; region effect, p = 0.0007, partial η2 = 0.091). We found high expression of IL-1β (group effect, p < 0.00001, partial η2 = 0.944) in the OA, HVLP-S, and HVLP-P groups without regional differences (p = 0.16). PMI behaved similarly (group effect, p < 0.00001, partial η2 = 0.832). Conclusion PC III expression is higher in nondependent regions and in ventilatory strategies that caused overdistension. This response was partially attenuated by prone positioning.
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Abstract Findings We set out to analyse the gene expression profile of pre-osteoblastic C2C12 cells during osteodifferentiation induced by both rhBMP2 and rhBMP7 using DNA microarrays. Induced and repressed genes were intercepted, resulting in 1,318 induced genes and 704 repressed genes by both rhBMP2 and rhBMP7. We selected and validated, by RT-qPCR, 24 genes which were upregulated by rhBMP2 and rhBMP7; of these, 13 are related to transcription (Runx2, Dlx1, Dlx2, Dlx5, Id1, Id2, Id3, Fkhr1, Osx, Hoxc8, Glis1, Glis3 and Cfdp1), four are associated with cell signalling pathways (Lrp6, Dvl1, Ecsit and PKCδ) and seven are associated with the extracellular matrix (Ltbp2, Grn, Postn, Plod1, BMP1, Htra1 and IGFBP-rP10). The novel identified genes include: Hoxc8, Glis1, Glis3, Ecsit, PKCδ, LrP6, Dvl1, Grn, BMP1, Ltbp2, Plod1, Htra1 and IGFBP-rP10. Background BMPs (bone morphogenetic proteins) are members of the TGFβ (transforming growth factor-β) super-family of proteins, which regulate growth and differentiation of different cell types in various tissues, and play a critical role in the differentiation of mesenchymal cells into osteoblasts. In particular, rhBMP2 and rhBMP7 promote osteoinduction in vitro and in vivo, and both proteins are therapeutically applied in orthopaedics and dentistry. Conclusion Using DNA microarrays and RT-qPCR, we identified both previously known and novel genes which are upregulated by rhBMP2 and rhBMP7 during the onset of osteoblastic transdifferentiation of pre-myoblastic C2C12 cells. Subsequent studies of these genes in C2C12 and mesenchymal or pre-osteoblastic cells should reveal more details about their role during this type of cellular differentiation induced by BMP2 or BMP7. These studies are relevant to better understanding the molecular mechanisms underlying osteoblastic differentiation and bone repair.
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Primary hyperparathyroidism associated with multiple endocrine neoplasia type I (hyperparathyroidism/multiple endocrine neoplasia type 1) differs in many aspects from sporadic hyperparathyroidism, which is the most frequently occurring form of hyperparathyroidism. Bone mineral density has frequently been studied in sporadic hyperparathyroidism but it has very rarely been examined in cases of hyperparathyroidism/multiple endocrine neoplasia type 1. Cortical bone mineral density in hyperparathyroidism/multiple endocrine neoplasia type 1 cases has only recently been examined, and early, severe and frequent bone mineral losses have been documented at this site. Early bone mineral losses are highly prevalent in the trabecular bone of patients with hyperparathyroidism/multiple endocrine neoplasia type 1. In summary, bone mineral disease in multiple endocrine neoplasia type 1related hyperparathyroidism is an early, frequent and severe disturbance, occurring in both the cortical and trabecular bones. In addition, renal complications secondary to sporadic hyperparathyroidism are often studied, but very little work has been done on this issue in hyperparathyroidism/multiple endocrine neoplasia type 1. It has been recently verified that early, frequent, and severe renal lesions occur in patients with hyperparathyroidism/multiple endocrine neoplasia type 1, which may lead to increased morbidity and mortality. In this article we review the few available studies on bone mineral and renal disturbances in the setting of hyperparathyroidism/multiple endocrine neoplasia type 1. We performed a meta-analysis of the available data on bone mineral and renal disease in cases of multiple endocrine neoplasia type 1-related hyperparathyroidism.
Surgical approach to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2
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We briefly review the surgical approaches to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2 (medullary thyroid carcinoma/multiple endocrine neoplasia type 2). The recommended surgical approaches are usually based on the age of the affected carrier/patient, tumor staging and the specific rearranged during transfection codon mutation. We have focused mainly on young children with no apparent disease who are carrying a germline rearranged during transfection mutation. Successful management of medullary thyroid carcinoma in these cases depends on early diagnosis and treatment. Total thyroidectomy should be performed before 6 months of age in infants carrying the rearranged during transfection 918 codon mutation, by the age of 3 years in rearranged during transfection 634 mutation carriers, at 5 years of age in carriers with level 3 risk rearranged during transfection mutations, and by the age of 10 years in level 4 risk rearranged during transfection mutations. Patients with thyroid tumor >5 mm detected by ultrasound, and basal calcitonin levels >40 pg/ml, frequently have cervical and upper mediastinal lymph node metastasis. In the latter patients, total thyroidectomy should be complemented by extensive lymph node dissection. Also, we briefly review our data from a large familial medullary thyroid carcinoma genealogy harboring a germline rearranged during transfection Cys620Arg mutation. All 14 screened carriers of the rearranged during transfection Cys620Arg mutation who underwent total thyroidectomy before the age of 12 years presented persistently undetectable serum levels of calcitonin (<2 pg/ml) during the follow-up period of 2-6 years. Although it is recommended that preventive total thyroidectomy in rearranged during transfection codon 620 mutation carriers is performed before the age of 5 years, in this particular family the surgical intervention performed before the age of 12 years led to an apparent biochemical cure.