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1.
Int J Oral Maxillofac Surg ; 45(3): 323-31, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26584852

ABSTRACT

Temporomandibular disorders (TMD) are associated with comorbidity. Shoulder pain is among the symptoms associated with TMD. The purpose of this study was to investigate the association between TMD and rotator cuff disease (RCD) and related genetic aspects. All subjects underwent orofacial and shoulder examinations. The control group comprised 30 subjects with no pain. Affected subjects were divided into three groups: RCD (TMD-free, n=16), TMD (RCD-free, n=13), and TMD/RCD (patients with both RCD and TMD, n=49). A total of eight single nucleotide polymorphisms in the ESRRB gene were investigated. A chemiluminescent immunoassay was used to measure estradiol levels. Surface electromyography recorded head and cervical muscle activity. The χ(2) test and Student t-test/Mann-Whitney test were used to assess the significance of nominal and continuous variables. A P-value of <0.05 was considered significant. TMD subjects were seven times more susceptible to RCD than controls. The rs1676303 TT (P=0.02) and rs6574293 GG (P=0.04) genotypes were associated with RCD and TMD, respectively. TMD/RCD subjects showed associations with rs4903399 (P=0.02), rs10132091 (P=0.02), and CTTCTTAG/CCTCTCAG (P=0.01) haplotypes and lower muscle activity. Estradiol levels were similar among groups. This study supports TMD as a risk factor for RCD. ESRRB haplotypes and low muscle activity are common biomechanical characteristics in subjects with both diseases.


Subject(s)
Muscular Diseases/genetics , Polymorphism, Single Nucleotide , Receptors, Estrogen/genetics , Rotator Cuff , Temporomandibular Joint Disorders/genetics , Brazil , Comorbidity , Cross-Sectional Studies , Female , Humans , Male , Middle Aged
2.
ACS Appl Mater Interfaces ; 7(44): 24772-7, 2015 Nov 11.
Article in English | MEDLINE | ID: mdl-26495875

ABSTRACT

Crystalline carbon-based materials are intrinsically chemically inert and good heat conductors, allowing their applications in a great variety of devices. A technological step forward in heat dissipators production can be given by tailoring the carbon phase microstructure, tuning the CVD synthesis conditions. In this work, a rapid bottom-up synthesis of vertically aligned hybrid material comprising diamond thin platelets covered by a crystalline graphite layer was developed. A single run was designed in order to produce a high aspect ratio nanostructured carbon material favoring the thermal dissipation under convection-governed conditions. The produced material was characterized by multiwavelength Raman spectroscopy and electron microscopy (scanning and transmission), and the macroscopic heat flux was evaluated. The results obtained confirm the enhancement of heat dissipation rate in the developed hybrid structures, when compared to smooth nanocrystalline diamond films.

3.
Mater Sci Eng C Mater Biol Appl ; 54: 196-206, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26046283

ABSTRACT

Titanium (Ti) is commonly used in dental implant applications. Surface modification strategies are being followed in last years in order to build Ti oxide-based surfaces that can fulfill, simultaneously, the following requirements: induced cell attachment and adhesion, while providing a superior corrosion and tribocorrosion performance. In this work micro-arc oxidation (MAO) was used as a tool for the growth of a nanostructured bioactive titanium oxide layer aimed to enhance cell attachment and adhesion for dental implant applications. Characterization of the surfaces was performed, in terms of morphology, topography, chemical composition and crystalline structure. Primary human osteoblast adhesion on the developed surfaces was investigated in detail by electronic and atomic force microscopy as well as immunocytochemistry. Also an investigation on the early cytokine production was performed. Results show that a relatively thick hybrid and graded oxide layer was produced on the Ti surface, being constituted by a mixture of anatase, rutile and amorphous phases where calcium (Ca) and phosphorous (P) were incorporated. An outermost nanometric-thick amorphous oxide layer rich in Ca was present in the film. This amorphous layer, rich in Ca, improved fibroblast viability and metabolic activity as well as osteoblast adhesion. High-resolution techniques allowed to understand that osteoblasts adhered less in the crystalline-rich regions while they preferentially adhere and spread over in the Ca-rich amorphous oxide layer. Also, these surfaces induce higher amounts of IFN-γ cytokine secretion, which is known to regulate inflammatory responses, bone microarchitecture as well as cytoskeleton reorganization and cellular spreading. These surfaces are promising in the context of dental implants, since they might lead to faster osseointegration.


Subject(s)
Calcium/chemistry , Dental Implants , Cell Adhesion , Cells, Cultured , Coated Materials, Biocompatible/chemistry , Cytokines/metabolism , Humans , Immunohistochemistry , Microscopy, Electron, Scanning , Nanostructures/chemistry , Osseointegration , Osteoblasts/cytology , Osteoblasts/metabolism , PPAR gamma/genetics , PPAR gamma/metabolism , Phosphorus/chemistry , Surface Properties , Titanium/chemistry , Vimentin/genetics , Vimentin/metabolism
4.
J Mech Behav Biomed Mater ; 49: 175-85, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26024650

ABSTRACT

The superior biotribological performance of nanocrystalline diamond (NCD) coatings grown by a chemical vapor deposition (CVD) method was already shown to demonstrate high wear resistance in ball on plate experiments under physiological liquid lubrication. However, tests with a close-to-real approach were missing and this constitutes the aim of the present work. Hip joint wear simulator tests were performed with cups and heads made of silicon nitride coated with NCD of ~10 µm in thickness. Five million testing cycles (Mc) were run, which represent nearly five years of hip joint implant activity in a patient. For the wear analysis, gravimetry, profilometry, scanning electron microscopy and Raman spectroscopy techniques were used. After 0.5 Mc of wear test, truncation of the protruded regions of the NCD film happened as a result of a fine-scale abrasive wear mechanism, evolving to extensive plateau regions and highly polished surface condition (Ra<10nm). Such surface modification took place without any catastrophic features as cracking, grain pullouts or delamination of the coatings. A steady state volumetric wear rate of 0.02 mm(3)/Mc, equivalent to a linear wear of 0.27 µm/Mc favorably compares with the best performance reported in the literature for the fourth generation alumina ceramic (0.05 mm(3)/Mc). Also, squeaking, quite common phenomenon in hard-on-hard systems, was absent in the present all-NCD system.


Subject(s)
Coated Materials, Biocompatible/chemistry , Diamond/chemistry , Hip Prosthesis , Materials Testing , Mechanical Phenomena , Nanoparticles/chemistry , Acetabulum , Femur , Silicon Compounds/chemistry , Surface Properties , Volatilization
5.
Minerva Stomatol ; 62(10): 405-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24217688

ABSTRACT

The aim of this paper was to present a case report of a male patient attending a Semiology and Stomatology Clinic with an erythematous ulcerated lesion on his palate. The patient reported that he was HIV positive as well as being addicted to cocaine. After a biopsy and a histopathological exam, he was diagnosed as having necrotizing sialometaplasia. The lesion diminished spontaneously in thirty days after the exam. Correct diagnosis as well as physical and complementary exams are paramount to avoid any incorrect therapy. As drug addiction and HIV infection have both been associated to necrotizing sialometaplasia, as in the present case, it is difficult to establish if the aetiological factor was drug usage or the HIV infection or even, the combination of these two factors. Although considering the influence of HIV infection on the oral health, we may assume that, at least, it favored the onset of this oral lesion.


Subject(s)
Cocaine-Related Disorders/complications , HIV Infections/complications , Sialometaplasia, Necrotizing/etiology , Adult , Humans , Male
6.
J Dent Res ; 90(8): 1019-25, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21586664

ABSTRACT

In spite of its role in the degradation of tooth-biomaterial interfaces, reports on nanoleakage are largely inconsistent. The aim of this work was to assess nanoleakage patterns qualitatively and quantitatively in 3D, to determine the influence of direction, position, and inclination of the field-of-view. Therefore, we applied a gold-standard 3-step etch-and-rinse adhesive to bur-cut dentin surfaces, after which interface samples were sectioned, infiltrated with an ammoniacal silver-nitrate solution, and embedded by common TEM procedures. High-resolution 3D models of interfaces were then generated by FIB and electron tomography, following strict conditions determined by Monte Carlo simulations. Inverted images in FIB tomography disclosed morphological characteristics analogous to those revealed by TEM. Quantitative analysis revealed large variations in silver-nitrate uptake between 2D image projections in different directions. Furthermore, silver-nitrate fractions in individual 2D image projections were seldom related to the total 3D volumetric fraction. Electron tomography showed that inclination also affected the morphology of silver-nitrate patterns. In conclusion, conventional nanoleakage evaluation is heavily influenced by direction, position, and inclination of the field-of-view, and thus may contain artifacts.


Subject(s)
Dental Bonding/adverse effects , Dental Leakage/diagnosis , Dentin-Bonding Agents , Dentin/pathology , Imaging, Three-Dimensional , Resin Cements , Artifacts , Coloring Agents , Dental Leakage/etiology , Imaging, Three-Dimensional/methods , Microscopy, Electron, Scanning/methods , Monte Carlo Method , Scattering, Radiation , Silver , Silver Nitrate , Tomography/methods
7.
Tissue Antigens ; 69(6): 607-10, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17498272

ABSTRACT

Two human leukocyte antigen (HLA)-DRB1 (HLA-DRB1*1376 and -DRB1*1465) and one HLA-A (HLA-A*2471) novel alleles have been identified in individuals from the Brazilian Bone Marrow Donor Registry. DNA sequencing of exon 2 for HLA-DRB1 alleles showed two and five nucleotide substitutions in -DRB1*1376 and -DRB1*1465, compared with closely related alleles, respectively. These substitutions result in a change of amino acid residues in HLA-DRB1*1376 at position 74 (Arg --> Glu) and in -DRB*1465 at positions 47 (Tyr --> Phe), 57 (Asp --> Ser) and 74 (Glu --> Ala). On the other hand, sequence analysis of exons 2 and 3 for HLA-A*2471 showed a single substitution, leading to a single amino acid change at position 151 (His --> Arg). These three novel alleles may have originated from other HLA alleles by gene conversion. However, it is also possible that HLA-A*2471 has evolved from one of the alleles of the HLA-A*2402 group through a point mutation.


Subject(s)
HLA-A Antigens/genetics , HLA-DR Antigens/genetics , Adult , Aged , Alleles , Amino Acid Substitution , Base Sequence , Brazil , Exons , Female , Gene Conversion , HLA-DRB1 Chains , Humans , Infant, Newborn , Male , Molecular Sequence Data , Point Mutation , Polymorphism, Single Nucleotide , Registries , Sequence Homology, Amino Acid , Tissue Donors
8.
Rev. bras. farmacogn ; 11(1): 13-19, 2001. ilus
Article in English | LILACS | ID: lil-528791

ABSTRACT

Bothrops venoms are composed by several protein fractions. Among these fractions there are myotoxins which induce an important muscle lesion. The purification of this component involves some steps, although providing a pure material, is time consuming. In the present study, we describe a quick method for myotoxin fraction isolation from the venom of Bolhrops nsuwiedi using one-step high performance liquid chromatography (HPLC). The complete procedure took 30 min. The pur6+y of the two myotoxic fractions isolated was assessed by SDS-PAGE. Upon i.m. injection into rat tibialis anterior, both toxins induced early morphological changes, indicating that the plasma membrane was the first cellular structure affected. Afterwards, the lesion was typically myonecrotic and inflammatory infiltrate was present.


Os venenos de Bolhrops são compostos por várias frações protéicas. Dentre elas, as miotoxinas induzem lesões musculares importantes. A purificação deste componente envolve várias etapas e, embora forneça frações puras, é muito trabalhosa. Neste trabalho foi descrito um método rápido para o isolamento da fração miotóxica do veneno de Bothrops neuwiedi (jararaca pintada), utilizando-se uma etapa única de purificação por Cromatografia Liquida de Alta Eficiência (CLAE). O procedimento completo demorou apenas 30 min. Foram isoladas duas frações com atividade miotóxica, cuja pureza foi verificada por eletroforese em gel de poliacrilamida-SDS. A injeção intramuscular no músculo tibial anterior de ratos induziu alterações morfológicas precoces, indicando que a membrana plasmática foi a primeira estrutura celular afetada pela fração miotóxica. A lesão muscular obtida foi tipicamente mionecrótica e foi observado infiltrado inflamatório.

9.
Chemosphere ; 40(4): 427-32, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10665409

ABSTRACT

This work reports a preliminary study of semiconductor-assisted photochemical degradation of lignin, Remazol Brilliant Blue R and Kraft E1 paper effluent by using ZnO and Ag-doped ZnO photocatalysts. The doped semiconductor was prepared in the reaction media by photoreduction of silver nitrate. With the use of 100 mg of ZnO and 15 mg of Ag-ZnO, almost total decolorization of the dye and lignin samples in reaction times lower than 60 min were observed. Extending the photochemical reaction up to 120 min, the total organic carbon content (TOC) was reduced in 90%. For the paper effluent, a fast decolorization was obtained for relatively short reaction times. However, de TOC reduction was negligible (near of 10%) up to high reaction times (300 min). By using the Ag-ZnO photocatalyst, the toxicity of lignin and Kraft E1 effluent toward E. Coli was completely removed. For the dye, the formation of transient toxic species was observed.


Subject(s)
Anthraquinones , Coloring Agents , Lignin , Semiconductors , Waste Management/methods , Water Pollutants, Chemical , Photolysis , Silver , Waste Management/instrumentation , Zinc Oxide
10.
Chemosphere ; 40(4): 433-40, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10665410

ABSTRACT

This work reports the semiconductor-assisted photochemical degradation of reactive dyes. In an oxygenated-UV-ZnO system almost total decolorization of Remazol Brilliant Blue R, Remazol Black B, Reactive Blue 221 and Reactive Blue 222 was observed in reaction times of about 60 min. Extending the photochemical treatment up to 120 min, mineralization higher than 80% for all the dyes was observed. During the same period, the residual acute toxicity was significantly reduced only for Remazol Black B. A systematic optimization study carried out by factorial design showed that for the reactive dyes tested, the ZnO semiconductor exhibits a better efficiency than that observed with anatase TiO2. A synergistic effect in the coupled TiO2-ZnO system was not observed.


Subject(s)
Coloring Agents , Semiconductors , Waste Management/instrumentation , Water Pollutants, Chemical , Anthraquinones/chemistry , Catalysis , Coloring Agents/chemistry , Hydrogen-Ion Concentration , Kinetics , Naphthalenesulfonates/chemistry , Photolysis , Solutions , Spectrophotometry , Waste Management/methods , Water
11.
Rev Saude Publica ; 31(6): 601-17, 1997 Dec.
Article in Portuguese | MEDLINE | ID: mdl-9629716

ABSTRACT

INTRODUCTION: Recent trends in hospital care in the State of Rio de Janeiro, Brazil, are analysed. The data are taken from the Unified Health Care System (SUS) and cover monthly observations between January 1992 and October 1995 for the public, teaching and private hospital subsectors. METHODOLOGY: The data entries are based on hospital declarations on the AIH form, processed by the National Inpatient Information System (SIH-SUS). When comparing the three subsectors, production of services and outcome were examined particularly closely. Comparisons are made using structural models for time series based on the break-down of a time series into components of interest, such as trend, seasonal variation and irregularity. RESULTS: The analysis shows a significant downward trend in the frequency of hospital admissions in the State of Rio de Janeiro, probably reflecting the deliberate withdraw of financial investments in this sector, which began in 1993. This reduction was selective with regard to age group distribution--being greater in the adult and elderly groups. The analysis has also shown that the teaching sector has steadily raised its admissions. The quality of care was analysed through the sentinel event approach. For the State of Rio de Janeiro as a whole, the occurrence of avoidable deaths during the hospital admission process shows a weak overall tendency to decline as detected by the reduction of this kind of death in the private sub-sector. In public and teaching hospitals the frequency of avoidable deaths has remained stable. The frequency of maternal deaths has remained high and stable, while the number of caesarean sections shows a significant increase, despite the high figures observed at the beginning of the period. CONCLUSIONS: The results of this study indicate an overall decline in the quality of health care offered by the SUS within the Rio de Janeiro State. Regardless of the existing limitations in SIH-SUS, this study has shown this to be a useful instrument for monitoring hospital care services.


Subject(s)
Delivery of Health Care/standards , Health Services/standards , Hospitals , Quality of Health Care , Adolescent , Adult , Aged , Brazil , Child , Child, Preschool , Databases as Topic , Female , Hospitalization/statistics & numerical data , Humans , Infant , Male , Middle Aged
13.
Genitourin Med ; 70(1): 30-4, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8300097

ABSTRACT

OBJECTIVE--To investigate whether bacteriuria and, specifically, symptomatic urinary tract infection (UTI) occur with increased frequency in men with HIV infection. METHODS--In this cross-sectional study we investigated three groups of men, aged from 18 to 50 years. Group A was composed of patients with a diagnosis of AIDS; Group B, of patients without HIV infection, and group C of patients with asymptomatic HIV infection. Patients with any known predisposing factor for UTI were excluded from the study. A clean-catch midstream urine sample was collected from each patient on the first day of hospital admission (groups A and B) or during a visit to the outpatient clinic (group C). Bacteriuria was diagnosed when > or = 100,000 colony forming units/ml, urine were grown. RESULTS--There were 415 patients, 151 in group A, 170 in group B and 94 in group C. Bacteriuria was significantly more frequently in group A (20 cases, 13.3%) than in groups B (3 cases, 1.8%, p = 0.00007) and C (3 cases, 3.2%, p = 0.009). Ten cases of bacteriuria in group A (6.6%) were symptomatic while no case of symptomatic UTI was seen in groups B (p = 0.0004) and C (p = 0.008). The frequency of UTI in homosexual men with AIDS (7 cases, 6.7%) was not significantly different from that observed in men with AIDS who denied homosexuality (3 cases, 6.5%). E coli was the predominant pathogen associated with UTI. Although adequate response to a two-week course of antibiotics was observed in most cases, an in-hospital mortality rate of 20% was found among AIDS patients with symptomatic UTI. CONCLUSIONS--In the present study, the frequency of bacteriuria and symptomatic UTI was found to be increased in men with AIDS. E coli was the predominant pathogen in these cases. These data suggest that symptomatic UTI may represent a relevant cause of morbidity for men with AIDS.


Subject(s)
AIDS-Related Opportunistic Infections/epidemiology , Bacteriuria/epidemiology , Urinary Tract Infections/epidemiology , AIDS-Related Opportunistic Infections/drug therapy , Adolescent , Adult , Anti-Bacterial Agents/therapeutic use , Bacteriuria/drug therapy , Cross-Sectional Studies , Homosexuality , Humans , Male , Middle Aged , Prevalence , Urinary Tract Infections/drug therapy
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