998 resultados para kartat - historialliset kartat - Pohjoisnapa - 1600-luku
Resumo:
Some patients with liver disease progress to cirrhosis, but the risk factors for cirrhosis development are unknown. Dyskeratosis congenita, an inherited bone marrow failure syndrome associated with mucocutaneous anomalies, pulmonary fibrosis, and cirrhosis, is caused by germline mutations of genes in the telomerase complex. We examined whether telomerase mutations also occurred in sporadic cirrhosis. In all, 134 patients with cirrhosis of common etiologies treated at the Liver Research Institute, University of Arizona, between May 2008 and July 2009, and 528 healthy subjects were screened for variation in the TERT and TERC genes by direct sequencing; an additional 1,472 controls were examined for the most common genetic variation observed in patients. Telomere length of leukocytes was measured by quantitative polymerase chain reaction. Functional effects of genetic changes were assessed by transfection of mutation-containing vectors into telomerase-deficient cell lines, and telomerase activity was measured in cell lysates. Nine of the 134 patients with cirrhosis (7%) carried a missense variant in TERT, resulting in a cumulative carrier frequency significantly higher than in controls (P = 0.0009). One patient was homozygous and eight were heterozygous. The allele frequency for the most common missense TERT variant was significantly higher in patients with cirrhosis (2.6%) than in 2,000 controls (0.7%; P = 0.0011). One additional patient carried a TERC mutation. The mean telomere length of leukocytes in patients with cirrhosis, including six mutant cases, was shorter than in age-matched controls (P = 0.0004). Conclusion: Most TERT gene variants reduced telomerase enzymatic activity in vitro. Loss-of-function telomerase gene variants associated with short telomeres are risk factors for sporadic cirrhosis. (HEPATOLOGY 2011;53:1600-1607)
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Development of hypoxic areas occurs during infectious and inflammatory processes and dendritic cells (DCs) are involved in both innate and adaptive immunity in diseased tissues. Our group previously reported that macrophages exposed to hypoxia were infected with the intracellular parasite Leishmania amazonensis, but showed reduced susceptibility to the parasite. This study shows that although hypoxia did not alter human DC viability, it significantly altered phenotypic and functional characteristics. The expression of CD1a, CD80, and CD86 was significantly reduced in DCs exposed to hypoxia, whereas CD11c, CD14, CD123, CD49 and HLA-DR expression remained unaltered in DCs cultured in hypoxia or normoxia. DC secretion of IL-12p70, the bioactive interleukin-12 (IL-12), a cytokine produced in response to inflammatory mediators, was enhanced under hypoxia. In addition, phagocytic activity (Leishmania uptake) was not impaired under hypoxia, although this microenviroment induced infected DCs to reduce parasite survival, consequently controlling the infection rate. All these data support the notion that a hypoxic microenvironment promotes selective pressure on DCs to assume a phenotype characterized by pro-inflammatory and microbial activities in injured or inflamed tissues and contribute to the innate immune response.
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The aim of this study was to evaluate and compare the efficacy of different remobilization protocols in different skeletal muscles considering the changes induced by hindlimb suspension of the tail. Thirty-six female Wistar rats were divided into six groups: control I, control II, suspended, suspended free, suspended trained on a declined treadmill and suspended trained on a flat treadmill. Fragments of soleus and tibialis anterior (TA) muscle were frozen and processed by different histochemical methods. The suspended soleus showed a significant increase in the proportional number of intermediate/hybrid fibers and a decrease in the number of type I fibers. Some of these changes proved to be reversible after remobilization. The three remobilization programs led to the recovery of both the proportional number of fibers and their size. The TA muscle presented a significant increase in the number and size of type I fibers and a cell size reduction of type IIB fibers, which were recovered after training on a declined treadmill and free movement. Especially regarding the soleus, the present findings indicate that, among the protocols, training on a declined treadmill was found to induce changes of a more regenerative nature, seemingly indicating a better tissue restructuring after the suspension procedure.
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Purpose: To evaluate the effects of panretinal photocoagulation (PRP) compared with PRP plus intravitreal bevacizumab on best corrected visual acuity (BCVA) and total area of fluorescein leakage from active new vessels (NVs) in patients with high-risk proliferative diabetic retinopathy (PDR). Methods: We carried out a prospective study of patients with high-risk PDR and no prior laser treatment who were randomly assigned to receive PRP (PRP group) or PRP plus intravitreal injection of 1.5 mg of bevacizumab (PRP-plus group). In all patients, the PRP was administered at two time-points (weeks 1 and 3), with the intravitreal bevacizumab delivered at the end of the second laser episode in the PRP-plus group. Standardized ophthalmic evaluation including Early Treatment Diabetic Retinopathy Study BCVA as well as stereoscopic fundus photography and fluorescein angiography were performed at baseline and at weeks 4, 9 (+/- 1) and 16 (+/- 2). Main outcome measures included changes in BCVA and in total area of fluorescein leakage from active NVs. Results: Twenty-two (n = 30 eyes) consecutive patients completed the 16-week follow-up. There was no significant difference between the PRP and PRP-plus groups with respect to age, gender, type or duration of diabetes, area of fluorescein leakage from active NVs or BCVA. No significant difference in BCVA was observed between the groups throughout the study period. However, the total area of actively leaking NVs was significantly reduced in the PRP-plus group compared with the PRP group at weeks 4, 9 and 16 (p < 0.001). No major adverse events were identified. Conclusions: In the short-term, the adjunctive use of intravitreal bevacizumab with PRP was associated with a greater reduction in the area of active leaking NVs than PRP alone in patients with high-risk PDR.
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Background: The presence of cancer stem cell (CSC) antigens can be evidenced in some human tumors by phenotypic analysis through immunostaining. This study aims to identify a putative CSC immunophenotype in oral squamous cell carcinoma (OSCC) and determine its influence on prognosis. Methods: The following data were retrieved from 157 patents: age, gender, primary anatomic site, smoking and alcohol intake, recurrence, metastases, histologic classification, treatment, disease-free survival (DFS), and overall survival (OS). An immunohistochemical study for CD44 and CD24 was performed in a tissue microarray of 157 paraffin blocks of OSCCs. Results: In univariate analysis, the immunostaining pattern showed significant influences in relation to OS for alcohol intake and treatment, as well as for the CD44+ and CD44-/CD24- immunophenotypes. The multivariate test confirmed these associations. Conclusions: Based on our results, the CD44 immunostaining and the absence of immunoexpression of these two investigated markers can be used in combination with other clinicopathologic information to improve the assessment of prognosis in OSCC.
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Neospora caninum is widely distributed in the world and this parasite is one of the major causes of abortion in cattle. Dogs and coyotes are definitive hosts of N. caninum and several species of domestic and wild animals are intermediate hosts. Dogs can become infected by the ingestion of tissues containing cysts and then excrete oocysts. It is not yet known whether sporulated oocysts are able to induce a patent infection in dogs, i.e. a shedding of N. caninum oocysts in feces. The objective of this study was to experimentally examine the infection of dogs by sporulated oocysts. The oocysts used in the experiment were obtained by feeding dogs with brain of buffaloes (Bubalus bubalis) positive for anti-N. caninum antibodies by indirect fluorescent antibody test (IFAT >= 200). Oocysts shed by these dogs were confirmed to be N. caninum by molecular methods and by bioassay in gerbils, and sporulated N. caninum oocysts were used for the oral infection of four dogs. The dogs were 8 weeks old and negative for antibodies to N. caninum and Toxoplasma gondii. Dogs 1 and 4 received an inoculum of 10,000 sporulated oocysts each; dog 2 an inoculum of 5000 sporulated oocysts and dog 3 received 1000 sporulated oocysts of N. caninum. The total feces excreted by these dogs were collected and examined daily for a period of 30 days. No oocysts were found in their feces. The dogs were monitored monthly for a 6-month period to observe a possible seroconversion and when this occurred the animals were eliminated from the experiment. Dogs 1 and 4 seroconverted 1 month after the infection with titer, in the IFAT, of 1600 and 800, respectively; the other two dogs presented no seroconvertion during the 6-month period. Dogs 1 and 2 were euthanized 180 days after infection and were examined for the detection of N. caninum in tissues (brain, muscle, lymph node, liver, lung, heart and bone marrow) by immunohistochemistry and PCR with negative results in both techniques. Bioassay in gerbils with brain of these dogs was also performed and again the results were negative. In conclusion, dogs infected with sporulated oocysts of N. caninum were not able to shed oocysts in feces. However, a higher dose of infection stimulated the production of antibodies against N. caninum in the dogs. (C) 2010 Elsevier B.V. All rights reserved.
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Background Iron accumulation was investigated qualitatively and quantitatively in the liver of 15 captive Brachyteles spp. Methods Hepatic hemosiderosis index (HHI) was determined as the area percentage of the liver parenchyma occupied by hemosiderin and ferritin deposits, through computerized histomorphometric analysis of Prussian blue-stained histologic sections. Results All studied animals presented liver hemosiderosis, and HHI ranged from 0.2% to 41.7%. There were no significant differences in HHI between muriqui species or genders, and no correlations were detected among HHI and age, time in captivity or body mass. Iron deposits were accompanied by other hepatic disorders. Conclusions This is the first study addressing the occurrence and consequences of iron overloading in the liver of muriquis. We propose that hemosiderosis may act as a contribute factor for the development of hepatic injuries. Further studies are advised to clarify the role of diet in the pathogenesis of hemosiderosis in these atelids.
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P>Aim The aim of this study was to investigate the possible associations between isolated growth hormone deficiency (IGHD) and periodontal attachment loss (PAL) in adults affected by congenital IGHD. Materials and methods Forty-five previously identified IGHD subjects were eligible for this study. The final study sample comprised 32 cases (gender:20M/12F; age:44.8 +/- 17.5) matched for age, gender, diabetes, smoking status and income to 32 controls (non-IGHD subjects). Participants were submitted to a full-mouth clinical examination of six sites per tooth and were interviewed using a structured, written questionnaire. Periodontitis was defined as proximal PAL >= 5 mm affecting >= 30% of teeth. Results No significant differences were observed in the percentage of sites with visible plaque between IGHD and non-IGHD subjects (59.4% versus 46.9%, p=0.32). IGHD subjects had significant less supragingival calculus (31.3% versus 59.4%, p=0.02) and more bleeding on probing (71.9% versus 18.8%, p < 0.01) than controls. PAL >= 5 mm was significantly more prevalent (100% versus 71.9%, p < 0.01) and affected more teeth (30.5% versus 6.7%, p < 0.01) in cases than in controls. After adjusting for supragingival calculus, IGHD cases had a higher likelihood of having periodontitis than controls (OR=17.4-17.8, 95% CI=2.3-134.9, p=0.004-0.005). Conclusion Congenital IGHD subjects have a greater chance of having PAL.
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Altered expression of extracellular matrix (ECM) components has been reported in several pathologies; however, few ECM proteins have been evaluated in adenomatoid odontogenic tumor (AOT). The aim of this study was to analyze the expression and distribution of the ECM proteoglycans: biglycan and decorin; and glycoproteins: osteonectin, osteopontin, bone sialoprotein and osteocalcin in the AOT. Three-micrometer sections from paraffin-embedded specimens were evaluated employing a streptavidin-biotin immunohistochemical method with the antibodies against the proteins previously cited. Only the osteonectin was expressed in the epithelial cells. The eosinophilic amorphous material and the connective tissue showed expression of all components studied. The calcification foci expressed only osteopontin. In conclusion, the low expression of the components studied in neoplastic epithelial cells suggests that the epithelial cells act probably as stimulators of the expression by the stroma, which in turn can act as agonist or antagonist of the tumor growth. These results suggest that the components studied probably have a key role in the biological behavior of the AOT.
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Background Prolonged exposure of the lip to sunlight may cause actinic cheilitis (AC) and squamous cell carcinoma (SCC). Maspin is a serpin with tumor suppressor functions. This work analyzed the presence and distribution of maspin in AC and lip SCC. Methods Sections from 36 cases diagnosed as AC (18 cases with mild epithelial dysplasia, 11 with moderate and 7 with severe), 18 cases diagnosed as lip SCC and 7 specimens containing normal lip vermillion epithelium were submitted for immunohistochemical analysis to detect maspin. Results All AC cases with mild and two cases with moderate dysplasia were scored 3. The remaining nine cases with moderate dysplasia were identified as score 2, whereas all cases with severe dysplasia were scored 1. Positive staining for maspin decreased from the basal layer to the surface. Among the 18 lip SCCs studied, 15 cases showed abundant staining for maspin. Epithelium adjacent to the SCCs also showed intense positive staining in all cells. Conclusions Our results suggest that the loss of maspin expression occurs from the basal layer to the surface. Lip SCCs related to solar radiation show an intense presence of maspin protein in almost all tumor cells as well as the neighboring epithelium. Fontes A, Sousa SM, Santos E, Martins MT. The severity of epithelial dysplasia is associated with loss of maspin expression in actinic cheilitis.
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Background: Galectin-3 has been implicated in tumor progression of some malignancies as thyroid, prostate, and salivary gland tumors. Recently, it has been suggested that this protein may be an important mediator of the beta-catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, the present study aimed to correlate galectin-3 expression with beta-catenin and cyclin D1 expressions in adenoid cystic carcinoma (ACC) and in polymorphous low-grade adenocarcinoma (PLGA). Methods: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of Sao Paulo and the proteins were analyzed by immunohistochemistry. Results: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for beta-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC (P < 0.05). Conclusions: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although beta-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.
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Background: Oncogenic Wnt/beta-catenin signaling occurs in numerous types of cancers, but little is known about the role of the Wnt protein family member, WNT-5A, in lip carcinogenesis. The aim of this study was to investigate WNT-5A, beta-catenin, and matrix metalloproteinase (MMP)-3 protein expression in actinic cheilitis (AC), and lip squamous cell carcinoma (LSCC). Methods: Twenty-one cases of AC, and fifty-one cases of LSCC were analyzed, with normal lip mucosa used as a control. Qualitative and semi-quantitative analyses of WNT-5A, beta-catenin, and MMP-3 immunostaining pattern and cellular distribution were performed. Results: WNT-5A was observed in more than 50% of the cells, scattered in all layers of AC, in contrast to the absence of immunostaining in normal lip mucosa. AC presented a higher level of WNT-5A expression than LSCC (P = 0.0289, Fisher test), while MMP-3 immunoexpression was statistically more significant in LSCC than in AC (P = 0.0285, Fisher test). Immunolabeling of beta-catenin protein was differentially distributed between samples; the majority of AC cases (61.90%) demonstrated a membranous-cytoplasmic pattern, while a considerable number of LSCC cases (29.41%) revealed a cytoplasmic pattern, instead of the usual membranous pattern. Conclusions: The present results suggest that WNT-5A may be an important marker during initial events of AC malignant transformation, in which non-canonical and canonical Wnt/beta-catenin signaling pathways could be involved. Additionally, WNT-5A might recruit other events in LSCC, such as MMP-3 protein synthesis, as its presence is increased in established malignant processes without beta-catenin dependency.
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Aim: The aim of the present study was to assess the influence of the chemical characteristics and roughness of titanium surfaces on the viability, proliferation and differentiation of osteoblast-like cells cultured in a medium supplemented with recombinant human bone morphogenetic protein-7 (rhBMP-7). Material and methods: Osteo-1 cells were grown on titanium disks presenting with the following surfaces: (1) machined, (2) coarse grit-blasted and acid-attacked (SLA) and (3) chemically modified SLA (SLAmod) in the absence or presence of 20 ng/ml rhBMP-7 in culture medium. The viability and number of osteo-1 cells were evaluated after 24 h. Analyses of total protein content (TP) and alkaline phosphatase (AP) activity at 7, 14 and 21 days, collagen content at 7 and 21 days and mineralized matrix formation at 21 days were performed. Results: Cell viability (P=0.5516), cell number (P=0.3485), collagen content (P=0.1165) and mineralized matrix formation (P=0.5319) were not affected by the different surface configurations or by the addition of rhBMP-7 to the medium. Osteo-1 cells cultured on SLA surfaces showed a significant increase in TP at 21 days. The ALPase/TP ratio (P=0.00001) was affected by treatment and time. Conclusion: The results suggest that the addition of rhBMP-7 to the culture medium did not exert any effect on the viability, proliferation or differentiation of osteoblast-like cells grown on the different surfaces tested. All titanium surfaces analyzed allowed the complete expression of the osteoblast phenotype such as matrix mineralization by osteo-1 cells.
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The burning mouth syndrome (BMS) is a chronic condition characterized by oral burning pain in the absence of clinical abnormalities and without established therapy. The purpose of this study was to evaluate the effectiveness of alpha lipoic acid (ALA) in the management of BMS symptoms through a randomized double-blind placebo-controlled trial. Thirty-eight patients (34 women and four men, median age 62.9 years, range 36-78) were included and 31 completed the study. The patients were randomized into two cycles of treatment: one with alpha lipoic acid and one with placebo both administered in identical capsules. These cycles were separated by a washout period of 20 days. The oral symptoms and the treatment response were assessed using a 100-mm visual analog scale before and after each cycle and the global perceived effect score, using a 5-point scale after each treatment cycle. The level of reduction on burning was significant for both treatments (paired t-test: P < 0.05; rp = 0.011; ral < 0.001). Considering the two cycles together, 22 patients reported at least some improvement after ALA use and 23 patients after placebo. Comparison of the oral assessment scores of the two cycles failed to demonstrate the effectiveness of ALA over placebo (t-test: P > 0.05; r = 0.75).
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Aims: The objective of this study was to compare the frequency of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) in subgingival plaque, saliva and peripheral blood of HIV-positive and-negative patients with periodontal disease. Materials and Methods: Fifty HIV-positive subjects (23 with gingivitis, 27 with periodontitis) and 50 healthy HIV-negative patients with chronic periodontitis were included in the study. Parameters of probing depth (PD), clinical attachment level (CAL), gingival index and plaque index were recorded. The samples were processed for viral identification by the nested polymerase chain reaction technique. Results: HCMV was the most prevalent virus in HIV-positive (82%) and-negative patients (84%), and the detection in the three samples was similar (p > 0.05). HSV-1 was the least prevalent virus in both groups, being detected in similar frequencies in oral sites and in peripheral blood. EBV-1 was found more frequently in saliva and subgingival plaque of HIV-positive patients than in HIV-negative patients (p <= 0.05). Conclusions: EBV-1 was more frequently recovered in oral sites of HIV-positive patients than in HIV-negative patients.