232 resultados para RF CAVITY
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The purpose of this in vitro study was to verify through micro tensile bond test the bond strength of an adhesive system irradiated with Nd:YAG laser in dentine previously treated with Er:YAG laser. Twenty caries free extracted human third molars were used. The teeth were divided in four experimental groups (n = 5): (G1) control group; (G2) irradiation of the adhesive system with the Nd:YAG laser; (G3) dentin treatment with Er:YAG laser; (G4) dentin treatment with Er:YAG laser followed by the irradiation of the adhesive system with Nd:YAG laser. The Er:YAG laser fluency parameter for the dentin treatment was of 60 J/cm(2). ne adhesive system was irradiated with the Nd:YAG laser with fluency of 100 J/cm(2). Dental restorations were performed with Adper Single Bond 2/Z250. One tooth from each group was prepared for the evaluation of the adhesive interface under SEM and bond failure tests were also performed and evaluated. The statistical analysis showed statistical significant difference between the groups G1 and G3, G1 and G4, G2 and G3, and G2 and G4; and similarity between the groups G1 and G2, and G3 and G4. The adhesive failures were predominant in all the experimental groups. The SEM analysis showed an adhesive interface with features confirming the results of the mechanical tests. The Nd:YAG laser on the adhesive system did not influence the bond strength in dentin treated or not with the Er:YAG laser.
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Schejter, L. and Mantelatto, F.L. 2011. Shelter association between the hermit crab Sympagurus dimorphus and the zoanthid Epizoanthus paguricola in the southwestern Atlantic Ocean. -Acta Zoologica (Stockholm) 92: 141-149. The available literature on zoanthid-hermit crab associations deals only with records of this phenomenon, providing no detailed information. We describe, for the first time, the shell-like colonies of Epizoanthus paguricola associated with the hermit crab Sympagurus dimorphus from benthic samples taken in the Argentine Sea, between 85 and 131 m depth, and provide information about morphometric relationships between the hermits and the zoanthids. In total, 260 specimens (137 males and 123 females) of S. dimorphus were collected, 240 (92.3%) of which were living in symbiosis with E. paguricola. The remaining 20 (7.7%) were living inside gastropod shells. As the initial structure of the pseudoshell, 12 different gastropod species were found (all were almost totally covered with colonies of E. paguricola). The hermit crab lives in the spiral cavity inside the soft colony, which seemed to be slightly different depending on the initial gastropod. Aperture pseudoshell morphology did not seem to be related to the sex of the hermit crab host, although males showed larger apertures for a given colony size. This fact is probably related to a larger size of male`s cheliped (sexual dimorphic character) used like a gastropod operculum and that may serve as a template for the growing of the aperture pseudoshell edge. The number of epizoanthid polyps per colony increased in relation to the weight of the colony and to the size of the hermit crab. A process of selection of the initial shell was evident, because species of Naticidae were not the most common gastropods in this benthic community, but were those most used by hermit crabs (> 60%). The puzzling association between hermit crab, shell and zoanthid presumably occurs during the hermit juvenile phase, when the crab occupies a small shell, and a zoanthid larva settles on it. Given the close relationship between S. dimorphus and E. paguricola found in this region, we support the idea that due to the low availability of adequate gastropod shells for hermit life cycle, this association allows the establishment and the continuity of the hermit crab population in the studied area.
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Nucleoside diphosphate kinases play a crucial role in the purine-salvage pathway of trypanosomatid protozoa and have been found in the secretome of Leishmania sp., suggesting a function related to host-cell integrity for the benefit of the parasite. Due to their importance for housekeeping functions in the parasite and by prolonging the life of host cells in infection, they become an attractive target for drug discovery and design. In this work, we describe the first structural characterization of nucleoside diphosphate kinases b from trypanosomatid parasites (tNDKbs) providing insights into their oligomerization, stability and structural determinants for nucleotide binding. Crystallographic studies of LmNDKb when complexed with phosphate, AMP and ADP showed that the crucial hydrogen-bonding residues involved in the nucleotide interaction are fully conserved in tNDKbs. Depending on the nature of the ligand, the nucleotide-binding pocket undergoes conformational changes, which leads to different cavity volumes. SAXS experiments showed that tNDKbs, like other eukaryotic NDKs, form a hexamer in solution and their oligomeric state does not rely on the presence of nucleotides or mimetics. Fluorescence-based thermal-shift assays demonstrated slightly higher stability of tNDKbs compared to human NDKb (HsNDKb), which is in agreement with the fact that tNDKbs are secreted and subjected to variations of temperature in the host cells during infection and disease development. Moreover, tNDKbs were stabilized upon nucleotide binding, whereas HsNDKb was not influenced. Contrasts on the surface electrostatic potential around the nucleotide-binding pocket might be a determinant for nucleotide affinity and protein stability differentiation. All these together demonstrated the molecular adaptation of parasite NDKbs in order to exert their biological functions intra-parasite and when secreted by regulating ATP levels of host cells.
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This work presents a new oxovanadium(IV)-cucurbit[6]uril complex, which combines the catalytic properties of the metal ion with the size-excluding properties of the macrocycle cavity. In this coordination compound, the VO(2-) ions are coordinated to the oxygen atoms located at the rim of the macrocycle in slightly distorted square-pyramidal configurations, which are in fact C(2v) symmetries. This combination results in a size-selective heterogeneous catalyst, which is able to oxidize linear alkanes like n-pentane at room temperature, but not styrene, cyclohexane or z-cyclooctene, which are too big to enter the cucurbit[6]uril cavity. The results presented here contribute to understanding the mechanism of alkane catalytic oxidation by oxovanadium(IV) complexes. (C) 2010 Elsevier Ltd. All rights reserved.
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The solubilization of an europium (III) beta-diketonate chelate in aqueous medium and the changes in its photophysical properties upon its inclusion into an alpha-cyclodextrin hydrophobic cavity are described. The complex [Eu(tta)(3)center dot(H(2)O)(2)] (tta = 4,4,4-trifluoro-1-(thiophen-2-yl)butane-1,3-dione) was synthesized, characterized, and incorporated into the hydrophobic cavity by stirring in an alpha-cyclodextrin aqueous solution. The inclusion was confirmed by (1)H NMR, and the stoichiometry of association was obtained by the Job method. The maximum in the excitation spectrum of the alpha-CD inclusion compound in aqueous solution was shifted 28 nm compared with the maximum of non alpha-CD complex. The emission spectrum of the association is similar to that of the free solid complex and displays the characteristic (5)D(0) -> (7)F(0-4) Eu(3+) transitions.
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Objective. To develop a questionnaire for the evaluation of sexuality of male patients with juvenile idiopathic arthritis (JIA). Methods. A cohort of male patients with rheumatoid factor (RF)-negative polyarticular. JIA according to the 2004 revised ILAR criteria and inactive disease was Studied. The Health Assessment Questionnaire (HAQ) was applied to all patients. As a control group, 120 age-matched males of the same socioeconomic status were evaluated. A self-administered Structured instrument, the Male Sexual Evaluation Questionnaire (MSEQ), was developed by multiprofessional experts to assess sexual life, including satisfaction, practice. and related functional aspects. Results. Thirty-two male patients with RF-negative polyarticular JIA [mean age 20.8 +/- 3.8 yrs (range 16-26), mean disease duration 15.4 +/- 3.6 yrs (range 13-20)] were studied. Mean HAQ score was 1.25 +/- 0.67 (range 0.1-2.1). Masturbation was practiced similarly by patients and controls (87.5% vs 91%; p > 0.999), although joint pain was observed in only 2 (7%) patients. Regular sexual intercourse (>= once/week) was reported by 78% of patients and 62% of controls (p = 0.86). Joint pain during intercourse was more frequent in patients (48% vs 3% in controls; p < 0.001). The mean HAQ score was higher in the 12 patients with,joint pain (hips = 3, knees = 5, and hips + knees = 4) during intercourse compared to the 13 patients without joint pain (1.82 +/- 0.27 vs 1.43 +/- 0.32; p < 0.05). Preserved desire and satisfaction were universal findings for all JIA patients and controls. Conclusion. The MSEQ was applicable to this cohort of male patients with RF-negative polyarticular JIA and showed that sexual life is preserved despite longterm disease, morbidity/functional dysfunction, and joint pain. (First Release May 1 2009: J Rheumatol 2009;36: 1337-42; doi: 10.3899/jrheum.080867)
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Introduction: Findings suggest that obsessive-compulsi e disorder (OCD) and related disorders, referred to as obsessive-compulsive spectrum disorders (OCSDs), are more common in patients with rheumatic fever (RF). Objectives: To determine whether RF or Sydenham`s chorea increases the probability of anxiety disorders in the relatives of individuals with RF with and without SC. Methods: This was a case-Control family study in which 98 probands and 389 first-degree relatives (FDRs) were assessed using structured psychiatric interviews. A Poisson regression model was used to determine whether the presence of any disorder in one family member influences the rate of disorders in the remaining family members. Results: Generalized anxiety disorder (GAD) occurred more frequently in the FDRs of RF probands than in those of control probands (P=.018). The presence of RF,GAD, or separation anxiety disorder in one family member significantly increased the chance of OCSDs in another member of the family.
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Autoimmune rheumatic diseases are generally considered as a multifactorial aetiology, mainly genetic susceptibility combined with environmental triggers of which bacteria are considered one of the most prominent. Among the rheumatic diseases where bacterial agents are more clearly involved as triggers are: reactive arthritis (ReA), rheumatic fever (RF) and Lyme disease. The role of bacterial infections in inducing other seronegative spondyloarthritis and antiphospholipid antibody syndrome has been hypothesized but is still not proven. The classic form of ReA is associated with the presence of HLA-B27 and is triggered by the urethritis or enteritis causing pathogens Chlamydia trachomatis and the enterobacteria Salmonella, Shigella, and Yersinia, respectively. But several other pathogens such as Brucella, Leptospira, Mycobacteria, Neisseria, Staphylococcus and Streptococcus have also been reported to cause ReA. RF is due to an autoimmune reaction triggered by an untreated throat infection by Streptococcus pyogenes in susceptible individuals. Carditis is the most serious manifestation of RF and HLA-DR7 is predominantly observed in the development of valvular lesions. Lyme disease is a tick-transmitted disease caused by the spirochete Borrelia burgdorferi. Knowledge is limited about how this spirochete interacts with human tissues and cells. Some data report that Borrelia burgdorferi can manipulate resident cells towards a pro- but also anti-inflammatory reaction and persist over a long period of time inside the human body or even inside human cells.
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Studies evaluating radiologic aspects, local complications, and structural alterations of the paranasal sinus in patients with mucosal leishmaniasis (ML) are lacking The aim of this study was to analyze alterations of the paranasal sinuses in patients with ML by using computed tomography (CT) scans This prospective study evaluated 26 patients in Brazil with ML Nom December 2008 through June 2009 All patients underwent CT scans of the paranasal sinuses Paranasal thickening was observed in 25 patients (96%) Nasal perforation was observed in 17 patients (65%) Those patients who received re-treatment showed more abnormalities on CT scan than cured patients (P < 0 05) Complications of ML are not limited to the nasal mucosa but extend to the paranasal sinuses. Mucosa! thickening. pacified air cells. bony remodeling, and bony thickening caused by inflammatory steals of the sinus cavity walls are CT findings suggestive of chronic sinusitis
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To evaluate the usefulness of intraoral ultrasonography (IOUS) as a tool for predicting neck metastasis. Squamous cell carcinoma (SCC) of the tongue is aggressive and has a great propensity to metastasize to cervical lymph nodes. SCC of the oral cavity has a worse prognosis when associated with metastatic cervical nodes. Therefore, the metastatic potential of tongue carcinoma should be graded preoperatively to help determine the requirement for neck dissection. Nineteen patients (11 men, 8 women) between 36 and 79 years of age (mean age 60) with T1 to T4a TNM-stage tongue carcinomas were evaluated preoperatively with IOUS. Clinical and pathological TNM classifications were performed. The average tumor thicknesses measured using histological sections were significantly (p < 0.01) lower than those with IOUS (1.3 vs. 1.6 cm, respectively). A significant correlation was observed between the tumor thickness measured using ultrasonography and that measured using histological sections (pathology). Based on this greater accuracy, the cutoff point of tumor thickness based on IOUS evaluation for predicting neck metastasis was determined to be 1.8 cm. Some factors may influence neck metastasis. A knowledge of these would help to avoid unnecessary surgical intervention for N0 patients. The results of this study indicates that there is a significant correlation between neck metastasis and tumor thickness. Intraoral ultrasonography is useful tool for identifying tongue tumors and measuring their thickness, with the thickness measured by IOUS showing a very good correlation with histological measurements. Moreover, IOUS provides prognostic information prior to surgical treatment since tumor thickness can predict the chance of recognizing metastatic cervical nodes.
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Carbon dioxide (CO(2)) has been used in the food industry as an antimicrobial agent. This study aimed to investigate whether CO(2) pneumoperitoneum might act similarly as an antimicrobial agent in the infected peritoneal cavity. Peritonitis was induced in 58 rats by intraabdominal injection of an Escherichia coli inoculum (6 x 105 colony-forming units [CFU]/ml). Control rats were injected with saline solution. The rats were randomly divided into four groups: rat control (RC, n = 15), bacterial inoculation control (BIC, n = 10), bacterial inoculation and laparotomy (BIL, n = 17), and bacterial inoculation and CO(2) pneumoperitoneum (BIP, n = 16). The survival rates and histopathologic changes in the abdominal wall muscles, spleen, liver, intestines, and omentum were evaluated, and the samples were classified as ""preserved"" or ""inflamed"" (acute inflammation or tissue regeneration). The survival rates for the four groups were as follows: RC (100%), BIP (75%), BIL (53%), and BIC (30%). With regard to survival rates, statistically significant differences were observed between the following groups: RC and BIC (p = 0.0009), RC and BIL (p = 0.0045), BIP and BIC (p = 0.0332), and RC and BIP (p = 0.0470). No significant differences regarding survival rates were observed between the BIL and BIC groups or between the BIP and BIL groups. With regard to the number of inflamed samples per group, a statistically significant difference was observed between the BIC and RC groups and the BIL and RC groups (p = 0.05). Carbon dioxide pneumoperitoneum has a protective effect against bacterial peritonitis induced in rats.
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Background: The high missed occult small bowel injuries (SBI) associated with laparoscopy in trauma (LIT) is a major reason why some surgeons still preclude LIT today. No standardized laparoscopic examination for evaluation of the peritoneal cavity is described for trauma. The objective of this article is to verify if a systematic standardized laparoscopic approach could correctly identify SBI in the peritoneal cavity for penetrating abdominal trauma (PAT). Methods: Victims with PAT were evaluated in a prospective, nonrandomized study. A total of 75 hemodynamically stable patients with suspected abdominal injuries were operated by LIT and converted to laparotomy if criteria were met: SBI and lesions to blind spot zones-retroperitoneal hematoma, injuries to segments VI or VII of the liver, or injuries to the posterior area of the spleen. Inclusion criteria were equivocal evidence of abdominal injuries or peritonea] penetration; systolic blood pressure >90 mm Hg and <3 L of IV fluids in the first hour of admission; Glasgow Coma Scale score >12; and age >12 years. Exclusion criteria were back injuries; pregnancy; previous laparotomy; and chronic cardiorespiratory disease. Results: Sixty patients were males and there were 38 stab wounds and 37 gunshot wounds. No SBI was missed, but a pancreatic lesion was undiagnosed due to a retroperitoneal hematoma. Twenty patients (26.6%) were converted. Unnecessary laparotomies were avoided in 73.33%. Therapeutic LIT was possible in 22.7%. Accuracy was 98.66% with 97.61% sensitivity and 100% specificity. Conclusions: Standard systematic laparoscopic exploration was 100% effective to detect SBI in the peritoneal cavity. Conversion from LIT to laparotomy should be done if injuries to blind spot zones are found which are poorly evaluated by LIT. Therapeutic LIT is feasible in PAT.
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Aims: To evaluate the IL1RN polymorphism as a possible marker for Rheumatic Fever (RF) susceptibility or disease severity. Methods: The genotypes of 84 RF patients (Jones criteria) and 84 normal race-matched controls were determined through the analysis of the number of 86-bp tandem repeats in the second intron of IL1RN. The DNA was extracted from peripheral-blood leukocytes and amplified with specific primers. Clinical manifestations of RF were obtained through a standardized questionnaire and an extensive chart review. Carditis was defined as new onset cardiac murmur that was perceived by a trained physician with corresponding valvae regurgitation or stenosis on echocardiogram. Carditis was classified as severe in the presence of congestive heart failure or upon the indication for cardiac surgery. The statistical association among the genotypes, RF and its clinical variations was determined. Results: The presence of allele I and the genotype A1/A1 were found less frequently among patients with severe carditis when compared to patients without this manifestation (OR = 0.11, p = 0.031; OR = 0.092, p = 0.017). Neither allele I nor allele 2 were associated with the presence of RF (p = 0.188 and p = 0.106), overall carditis (p = 0.578 and p = 0.767), polyarthritis (p = 0.343 and p = 0.313) and chorea (p = 0.654 and p = 0.633). Conclusion: In the Brazilian population, the polymorphism of the IL-1ra gene is a relevant factor for rheumatic heart disease severity. (C) 2009 Elsevier Ltd. All rights reserved.
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Rheumatic fever (RF) is an autoimmune disease caused by the gram-positive bacteria Streptococcus pyogenes that follows a nontreated throat infection in susceptible children. The disease manifests as polyarthritis, carditis, chorea, erythema marginatum, and/or subcutaneous nodules. Carditis, the most serious complication, occurs in 30% to 45% of RF patients and leads to chronic rheumatic heart disease (RHD), which is characterized by progressive and permanent valvular lesions. In this review, we will focus on the genes that confer susceptibility for developing the disease, as well as the innate and adaptive immune responses against S. pyogenes during the acute rheumatic fever episode that leads to RHD autoimmune reactions. The disease is genetically determined, and some human leukocyte antigen class II alleles are involved with susceptibility. Other single nucleotide polymorphisms for TNF-alpha and mannan-binding lectin genes were reported as associated with RF/RHD. T cells play an important role in RHD heart lesions. Several autoantigens were already identified, including cardiac myosin epitopes, vimentin, and other intracellular proteins. In the heart tissue, antigen-driven oligoclonal T cell expansions were probably the effectors of the rheumatic heart lesions. These cells are CD4(+) and produced inflammatory cytokines (TNF alpha and IFN gamma). Molecular mimicry is the mechanism that mediated the cross-reactions between streptococcal antigens and human proteins. The elucidation of chemokines and their receptors involved with the recruitment of Th1, Th2, and Th17 cells, as well as the function of T regulatory cells in situ will certainly contribute to the delineation of the real picture of the heart lesion process that leads to RHD.
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INTRODUCTION The management of nonpalpable testicular masses is a challenging task, and coexisting infertility can further complicate the treatment decisions. We present our technique for microsurgical organ-sparing resection of incidental nonpalpable testicular nodules combined with microdissection for testicular sperm extraction and tissue cryopreservation in azoospermic patients. TECHNICAL CONSIDERATIONS Five infertile patients with azoospermia presented with nonpalpable hypoechoic testicular masses that were detected by Ultrasonography and underwent organ-sparing surgery. The testis was delivered through an inguinal incision, and the blood circulation was interrupted with a vascular clamp placed on the spermatic cord. Sludged ice was used to prevent warm ischemia, and a temperature probe was used to control the temperature at 12 degrees-15 degrees C. Real-time reflex ultrasonography was used to locate the tumor, and a stereotaxic hook-shaped needle was inserted under ultrasound guidance. The needle was placed adjacent to the tumor to guide the microsurgical resection. The tunica albuginea was incised over the tumor, which was dissected and removed, along with the adjoining parenchymal tissue. Frozen section studies were performed and, if malignancy was confirmed, biopsies of the tumor cavity margins and remaining parenchyma were obtained to ensure the absence of residual tumor. Microdissection was performed for excision of selected enlarged tubules that were processed and cryopreserved. CONCLUSIONS We present a technique for microsurgical organ-sparing resection of testicular tumor and sperm extraction that can be used in selected infertile patients with azoospermia in whom incidental masses have been diagnosed by ultrasonography. This conservative approach should be especially considered for patients with a solitary testis or bilateral tumors. UROLOGY 73: 887-892, 2009. (C) 2009 Elsevier Inc.