971 resultados para online damage detection
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Animals kept as pets may be considered sentinels for environmental factors to which humans could be exposed. Olfactory and respiratory epithelia are directly subjected to airborne factors, which could cause DNA lesions, and the alkaline comet assay is considered a reliable tool for the assessment of DNA damage. The objective of this work is to evaluate the extent of DNA damage by the comet assay of the olfactory and respiratory epithelia of dogs from different regions of the city of sao Paulo, Brazil. Thirty-three clinically healthy dogs, aged 5 years or more, were used in the study, with 7 from the North region of Sao Paulo, 7 from the South region, 3 dogs from the East region, and 16 dogs from the West city region. Three dogs younger than 6 months were used as controls. DNA damage was analyzed by the alkaline comet assay. We observed no difference in histopathological analysis of olfactory and respiratory epithelia between dogs from different regions of Sao Paulo. Dogs older than 5 years presented significantly higher comet length in both olfactory and respiratory epithelia, when compared with controls, indicating DNA damage. When separated by regions, olfactory and respiratory epithelia presented similar DNA damage in dogs from different regions of Sao Paulo, corroborating with similar levels of particulate matter index (PM10) in all regions of the city. In this study, we report for the first time that the comet assay can be used to quantify the extent of DNA damage in dog olfactory and respiratory epithelia, and that comet length (DNA damage) increases with age, probably due to environmental factors. Air pollution, as measured by PM 10, can be responsible for this DNA damage. (C) 2009 Elsevier GmbH. All rights reserved.
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Turkey coronavirus (TCoV) is a causative agent associated with poult enteritis and mortality syndrome (PEMS) in turkeys worldwide. The disease is an acute, highly contagious enteric disease that is characterized by depression, anorexia, diarrhea, and high mortality in commercial turkey flocks. The presence of TCoV in 12 intestinal-content samples, from turkey flocks aged between 10 and 104 days and exhibiting severe enteritis, was monitored during the period of 2004 to 2006. TCoV detection was accomplished by a reverse transcriptase-polymerase chain reaction (RT-PCR) through amplification of the 3` UTR region, followed by amplification of genes 3 and 5. Molecular characterization of the viruses was done through amplification of genes 3 and 5 and showed evidence of genetic similarity between them, although they differed from sequences of other TCoVs described in the literature. In relation to gene 3, samples showed a greater relationship with chicken infectious bronchitis virus (IBV), while gene 5 showed greater identity with pheasant coronavirus (PhCoV). Our results suggest that the strategy of amplification of the 3` UTR region, followed by sequencing of genes 3 and 5, has proven to be an effective means of detecting TCoV in intestinal contents.
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Homozygous familial hypercholesterolemia (HoFH) is a rare disorder characterized by the early onset of atherosclerosis, often at the ostia of coronary arteries. In this study we document for the first time that aortic and coronary atherosclerosis can be detected using 64 slice multiple detector row computed tomographic coronary angiography (CTCA). We studied five HoFH patients (three females, two males, mean age 19.8 +/- 2.9 years, age range 15-23 years, with a mean low density lipoprotein (LDL) cholesterol 618 +/- 211 mg/dL) using 64 slice CTCA. None of the patients showed evidence of ischemia with standard exercise testing. Calcified and mixed atherosclerotic plaques adjacent to or compromising the coronary artery ostia were found in all study subjects. Coronary plaques causing significant obstruction were found in one patient, who had previously undergone coronary artery bypass surgery and aortic valve replacement. Two other patients were noted to have non-obstructive calcified, mixed and non-calcified coronary artery plaques. Our data suggest that CTCA could be a useful non-invasive method for detection of early aortic and coronary atherosclerosis specifically affecting the coronary ostia in HoFH subjects. (c) 2007 Elsevier Ireland Ltd. All rights reserved.
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Introduction: The aim of the present study was to test the accuracy of small-volume cone-beam computed tomography (CBCT) scanning in the detection of horizontal root fractures and to assess the influence of a metallic post. Methods: Forty teeth were divided into four groups based on the presence of metallic posts and horizontal root fracture. The teeth were examined by small-volume CBCT scanning at 0.2-mm voxel resolution. Three observers analyzed the samples for the presence of a horizontal root fracture. Sensitivity and specificity were calculated. Results: High values for accuracy (73%-88%) were obtained in the groups without a metallic post, and statistically significant differences were found when the group with a metallic post has been observed (55%-70%). Intraobserver agreement also showed statistically significant differences in the groups with a metallic post. Conclusions: Small-volume CBCT scanning showed high accuracy in detecting horizontal root fracture without a metallic post. However, the presence of a metallic post significantly reduced the specificity and sensitivity of this examination. (J Endod 2011;37:1456-1459)
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Objective. TGIF1 homeobox gene involvement in oral cancer has not yet been investigated. This study analyzed the expression of TGIF1 transcripts and protein in oral squamous cell carcinoma (OSCC). Study design. Snap-frozen samples from 16 patients were taken from both OSCC and nontumoral adjacent epithelium (NT) for in situ hybridization (ISH). Forty-six paraffin-embedded samples of OSCC were submitted to immunohistochemistry (IHC). A descriptive analysis of the transcript signal detection was accomplished, and TGIF1 immunoexpression was carried out considering protein levels, localization, and cellular differentiation. Results. ISH reactions showed TGIF1 transcripts with a signal that was frequently intense in NT, and generally weak in OSCC, and that had stronger transcript signal in well-differentiated areas of OSCC when compared with poorly differentiated ones. IHC reactions had poorly differentiated cases associated with TGIF1 protein expression in both the nucleus and cytoplasm (P = .05, Fisher test). Conclusions. TGIF1 gain or loss of function might possibly play a role in oral cancer cell differentiation. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011; 111: 218-224)
Wildlife damage, insurance/compensation for farmers and conservation: Sri Lankan elephants as a case
Resumo:
The interference with agriculture has been recognised as the main cause for the current conflict between farmers and wild elephants in Sri Lanka, as elsewhere in the Asian elephant range. Thus compensating farmers for the damages caused by elephants is essential, if this endangered species is to survive in the long run. This paper explores the practicality of establishing an improved publicly funded insurance/compensation scheme to recompense farmers for the elephant damages. It does so by analysing results from two contingent valuation surveys undertaken in Sri Lanka. We find that possible public support of farmers plus urban dwellers significantly exceeds the financial requirement of the insurance scheme proposed in this study for perpetuity. The article also shows that it is often inappropriate from an economic viewpoint to analyse crop insurance as if it only involves the insurance of a private good because important positive externalities can arise from ‘crop’ damages by wildlife, e.g. elephants. The use of agricultural land by some species is essential for their long-term survival and this is often positively valued by the community as a whole.
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Purpose: The present study assessed damage to the inferior alveolar nerve (IAN) following nerve lateralization and implant placement surgery through optical and transmission electron microscopy (TEM). Materials and Methods: IAN lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, one implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant The implant was placed in the right mandible, and the left side was used as a control (no surgical procedure) After 8 weeks, the animals were sacrificed and samples were prepared for optical and TEM analysis of IAN structural damage Histomorphometric analysis was performed to determine the number and cross-sectional dimensions of nerve fascicles and myelin sheath thickness between experimental and control grouos. The different parameters were compared by one-way analysis of variance at the 95% significance level Results: Alterations in the perineural and endoneural regions of the IAN, with higher degrees of vascularization., were observed in the experimental group TEM showed that the majority of the myelinated nerve fibers were not affected in the experimental samples. No significant variation in the number of fascicles was observed, significantly larger fascicle height and width were observed in the control group, and significantly thicker myelin sheaths were observed in the experimental samples Conclusion: IAN lateralization resulted in substantial degrees of tissue disorganization at the microstructural level because of the presence of edema However, at the ultrastructural level, small amounts of fiber degeneration were observed. INT J ORAL MAXILLOFAC IMPLANTS 2009,24-859-865
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Background: Herpesviruses may be related to the etiology of aggressive periodontitis (AgP) and chronic periodontitis (CP) by triggering periodontal destruction or by increasing the risk for bacterial infection. This case-control study evaluated the presence of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus type 1 (EBV-1), human cytomegalovirus (HCMV), Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia (previously T. forsythensis) in patients with generalized AgP (AgP group), CP (CP group), or gingivitis (G group) and in healthy individuals (C group). Methods: Subgingival plaque samples were collected with paper points from 30 patients in each group. The nested polymerase chain reaction (PCR) method was used to detect HSV-1, EBV-1, and HCMV. Bacteria were identified by 16S rRNA-based PCR. Results: HSV-1, HCMV, and EBV-1 were detected in 86.7%, 46.7%, and 33.3% of the AgP group, respectively; in 40.0%, 50.0%, and 46.7% of the CP group, respectively; in 53.3%, 40.0%, and 20.0% of the G group, respectively; and in 20.0%, 56.7%, and 0.0% of the C group, respectively. A. actinomycetemcomitans was detected significantly more often in the AgP group compared to the other groups (P<0.005). P. gingivalis and T. forsythia were identified more frequently in AgP and CP groups, and AgP, CP, and G groups had higher frequencies of P. intermedia compared to the C group. Conclusion: In Brazilian patients, HSV-1 and EBV-1, rather than HCMV, were more frequently associated with CP and AgP. J Periodontol 2008;79:2313-2321.
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Objective: Although the general mechanisms of dentinogenesis are understood, several aspects regarding tertiary dentine formation still deserve investigation, especially regarding the presence and distribution of some noncollagenous matrix proteins. As dentine matrix protein 1 (DMP 1) is present in primary dentine, it is possible that this protein may also be present in the dentine matrix secreted after injury, but there are no immunocytochemical studies attempting its detection in tertiary dentine. The aim of this study was to examine the ultrastructural immunolocalization of DMP 1 in the tertiary dentine after extrusion of the rat incisor. Study design: Upper incisors were extruded 3 mm and then repositioned into their sockets. After several periods, the incisors were fixed and processed for transmission electron microscopy and for immunocytochemistry for DMP 1. Results: Extrusion yielded both types of tertiary dentine, which varied in aspect and related cells. DMP 1 was found in the mineralized matrix of all types of dentine, presenting high affinity for collagen, but rare colloidal gold particles over predentine. DMP 1 was evident in the supranuclear region and inside the nucleus of some odontoblast-like cells. Conclusion: The observed association between DMP 1 and collagen seem to be essential for reactionary and reparative dentine formation. (C) 2010 Elsevier Ltd. All rights reserved.
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Studies investigating the immunopathological aspects of Jorge Lobo`s disease have shown that the inflammatory infiltrate consists mainly of histiocytes and multinucleated giant cells involving numerous yeast-like cells of Lacazia loboi, with the T lymphocytes more common than B lymphocytes and plasma cells. The quantification of cytokines in peripheral blood mononuclear cells culture supernatant has revealed alterations in the cytokines profile, characterized by predominance of a Th2 profile. In view of these findings and of the role of cytokines in cell interactions, the objective of the present study was to investigate the presence of the cytokines IL-10, TGF-ss 1 and TNF-alpha, as well as iNOS enzyme in granulomas induced by L. loboi. Histological sections obtained from skin lesions of 16 patients were analyzed by immunohistochemistry for the presence of these cytokines and iNOS. The results showed that TGF-ss 1 was the cytokine most frequently expressed by cells present in the inflammatory infiltrate, followed by IL-10. There was a minimum to discrete positivity of cells expressing TNF-alpha and iNOS. The results suggest that the presence of immunosuppressive cytokines in skin lesions of patients with the mycosis might be responsible for the lack of containment of the pathogen as demonstrated by the presence of numerous fungi in the granuloma.
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Objectives: This study compared the reliability and fracture patterns of zirconia cores veneered with pressable porcelain submitted to either axial or off-axis sliding contact fatigue. Methods: Forty-two Y-TZP plates (12 mm x 12 mm x 0.5 mm) veneered with pressable porcelain (12 mm x 12 mm x 1.2 mm) and adhesively luted to water aged composite resin blocks (12 mm x 12 mm x 4 mm) were stored in water at least 7 days prior to testing. Profiles for step-stress fatigue (ratio 3:2:1) were determined from single load to fracture tests (n = 3). Fatigue loading was delivered on specimen either on axial (n = 18) or off-axis 30 degrees angulation (n = 18) to simulate posterior tooth cusp inclination creating a 0.7 mm slide. Single load and fatigue tests utilized a 6.25 mm diameter WC indenter. Specimens were inspected by means of polarized-light microscope and SEM. Use level probability Weibull curves were plotted with 2-sided 90% confidence bounds (CB) and reliability for missions of 50,000 cycles at 200 N (90% CB) were calculated. Results: The calculated Weibull Beta was 3.34 and 2.47 for axial and off-axis groups, respectively, indicating that fatigue accelerated failure in both loading modes. The reliability data for a mission of 50,000 cycles at 200 N load with 90% CB indicates no difference between loading groups. Deep penetrating cone cracks reaching the core-veneer interface were observed in both groups. Partial cones due to the sliding component were observed along with the cone cracking for the off-axis group. No Y-TZP core fractures were observed. Conclusions: Reliability was not significantly different between axial and off-axis mouth-motion fatigued pressed over Y-TZP cores, but incorporation of sliding resulted in more aggressive damage on the veneer. (C) 2009 Elsevier Ltd. All rights reserved.
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Cisplatin is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. This study evaluated the effects of peri-pubertal cisplatin administration on several reproductive end-points and the reversibility of these effects in adulthood. Peri-pubertal Wistar male rats (45 days old) were divided into two groups: control (saline 0.9%) and cisplatin (1 mg/kg/day, 5 days/week, for 3 weeks, i.p.). The study was conducted in two steps and evaluations were performed at ages of 66 (post-pubertal age) and 140 (adult age) days on: (i) organ weights, serum gonadotropins and testosterone levels, sperm counts, motility and morphology, testicular histomorphometry, spermatogenesis kinetics, Sertoli cell number and in situ detection of apoptotic germ cells and (ii) sexual behaviour, fertility and intratesticular testosterone. At the end of cisplatin therapy, rats showed reductions in sperm production and reserves, sperm with progressive movement, tubular diameter, intratesticular testosterone and fertility potential, but increased numbers of TUNEL-positive seminiferous tubules, immotile sperm and pre-implantation losses compared with control. Moreover, cisplatin-treated post-pubertal rats displayed impaired testicular histopathology and sexual behaviour. Serum gonadotropins and testosterone levels, sperm morphology, spermatogenesis kinetics and Sertoli cell number were comparable between experimental groups at both ages. Alterations found in post-puberty were recovered at adulthood, except for sperm motility and damage to testicular histology. The persistence of these cisplatin effects, despite the unaltered fertility after natural mating in rats, may have implications for reproductive function of young boys undergoing cancer therapy, given the lower reproductive efficiency in human beings compared with rats.