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1.
Sports Health ; 15(3): 410-421, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35678147

RESUMO

BACKGROUND: The Dynamic Exertion Test (EXiT) was developed to inform return-to-play (RTP) decision-making following clinical recovery from sport-related concussion (SRC). The purpose of the current study was to document intrarater and test-retest reliability and minimal detectable change (MDC) scores for physiological [heart rate (HR) and blood pressure], performance (change-of-direction task completion time and errors), and clinical outcomes (endorsed symptoms, perceived exertion) of EXiT, and interrater reliability of performance outcomes. HYPOTHESIS: Healthy athletes would exhibit stable physiological responses to the EXiT across visits, demonstrate consistent change-of-direction task completion time between consecutive trials at each visit, and the fastest time (of 2 trials) across visits, and endorse equivocal symptoms and effort across visits. STUDY DESIGN: Cross-sectional, test-retest. LEVEL OF EVIDENCE: Level 3. METHODS: Seventy-nine (female: 34 [43%], 19.6 ± 5.0 years) athletes completed the EXiT at 2 study visits (8.7 ± 4.7 days between visits). Two-way, mixed, intraclass correlation coefficients (ICCs) were used to evaluate intrarater and test-retest reliability. Cronbach's alpha was used to document the internal consistency of symptoms at each visit, and MDC scores were calculated on the physiological, performance, and clinical outcomes. RESULTS: Measured and percentage of age-estimated maximum HR were reliable following EXiT (ICC = 0.579-0.618). Change-of-direction task completion time (MDC range = 0.75-8.70 s) had good-to-excellent test-retest (ICC = 0.703-0.948) and interrater (ICC = 0.932-0.965) reliability. Symptoms had a high internal consistency at visits 1 (α = 0.894) and 2 (α = 0.805) and were reliable across visits (ICC = 0.588). CONCLUSION: The current investigation established test-retest reliability in addition to MDC scores of an objective dynamic exercise assessment among healthy adolescent and adult athletes. The EXiT may be an objective approach to inform RTP decision-making following SRC recovery. CLINICAL RELEVANCE: The EXiT is a clinically feasible exertion-based assessment that can be readily administered in a variety of outpatient clinical settings.


Assuntos
Concussão Encefálica , Esportes , Adulto , Adolescente , Humanos , Feminino , Esforço Físico , Reprodutibilidade dos Testes , Estudos Transversais , Concussão Encefálica/diagnóstico
2.
Life (Basel) ; 12(2)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35207458

RESUMO

BACKGROUND: From the start of the COVID-19 pandemic, new SARS-CoV-2 variants have emerged that potentially affect transmissibility, severity, and immune evasion in infected individuals. In the present systematic review, the impact of different SARS-CoV-2 variants on clinical outcomes is analyzed. METHODS: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020. Two databases (PubMed and ScienceDirect) were searched for original articles published from 1 January 2020 to 23 November 2021. The articles that met the selection criteria were appraised according to the Newcastle-Ottawa Quality Assessment Scale. RESULTS: Thirty-three articles were included, involving a total of 253,209 patients and 188,944 partial or complete SARS-CoV-2 sequences. The most reported SARS-CoV-2 variants showed changes in the spike protein, N protein, RdRp and NSP3. In 28 scenarios, SARS-CoV-2 variants were found to be associated with a mild to severe or even fatal clinical outcome, 15 articles reported such association to be statistically significant. Adjustments in eight of them were made for age, sex and other covariates. CONCLUSIONS: SARS-CoV-2 variants can potentially have an impact on clinical outcomes; future studies focused on this topic should consider several covariates that influence the clinical course of the disease.

3.
Int J Sports Physiol Perform ; 17(6): 834-843, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35213824

RESUMO

PURPOSE: To describe the Dynamic Exertion Test (EXiT) by comparing physiological, performance, and clinical outcomes between athletes medically cleared following sport-related concussion (SRC) and healthy controls. METHODS: One hundred four (female = 41, 39.4%) participants (14-21 y of age) including 52 medically cleared for return to play at 21.48 (15.40) days following SRC and 52 healthy athletes completed the EXiT involving (1) 12-minute aerobic component and (2) 18-minute dynamic component including 2 functional movement and 5 change-of-direction (COD) tasks. Physiological (heart rate and blood pressure), clinical (endorsed symptoms and rating of perceived exertion), and performance (COD-task completion time and errors) outcomes were collected throughout EXiT. Participants also completed the Postconcussion Symptom Scale and vestibular/ocular motor screening before EXiT. Independent-samples t tests were used to compare groups on resting heart rate and blood pressure, COD-task completion time, and Mann-Whitney U tests on Postconcussion Symptom Scale, vestibular/ocular motor screening, and EXiT symptoms, rating of perceived exertion, and errors. RESULTS: COD-task completion time and resting systolic blood pressure and heart rate were similar between groups (P > .05). SRC reported greater rating of perceived exertion during the aerobic component (P < .05) and lower total dizziness (P = .003) and total symptoms (P = .021) during EXiT and had lower near point of convergence distance (P < .001) and total symptoms (P = .007) for vestibular/ocular motor screening than healthy athletes. CONCLUSION: Physiological, performance, and clinical EXiT outcomes were equivocal between athletes at medical clearance following SRC and healthy controls. The multidomain EXiT may help to inform safe return-to-play decision making post-SRC.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Atletas , Concussão Encefálica/diagnóstico , Feminino , Humanos , Esforço Físico , Volta ao Esporte
4.
Cancer Cytopathol ; 128(10): 715-724, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32520446

RESUMO

BACKGROUND: The goal of this study was to determine whether the detection of histologically confirmed cases of cervical high-grade squamous intraepithelial lesions or worse (HSIL+) can be increased by having each liquid-based cytology (LBC) slide read by 2 cytotechnologists as part of routine screening. METHODS: Over 36,212 women aged 30 to 64 years participated in the Forwarding Research for Improved Detection and Access for Cervical Cancer Screening and Triage (FRIDA) Study in Mexico between 2013 and 2016. For each participant, 2 cervical samples were collected at the same clinic visit, one to test for high-risk human papillomavirus (hrHPV) and the other for LBC, which was used to triage those with a hrHPV positive result. LBC slides were evaluated by 7 cytotechnologists, with each slide read independently by 2 blinded cytotechnologists. All women with atypical cells of undetermined significance or a worse result were referred to colposcopy for further evaluation and diagnosis. Three pathologists evaluated the biopsy specimens to confirm the final HSIL+ diagnosis. The HSIL+ detection rates for the single versus double reading were estimated and compared. RESULTS: A total of 3,914 women with a positive hrHPV result were triaged with LBC. The first and second cytology readings resulted in 43 HSIL+ cases detected; the double-reading strategy detected 9 additional HSIL+ cases, resulting in a total of 52 HSIL+ cases. The HSIL+ detection rate increased from 10.99/1000 with a single reading to 13.29/1000 with the double-reading strategy (P = .004). CONCLUSION: A 20.9% increase in HSIL+ cases detected was achieved with a double reading of the LBC slides in this sample of hrHPV-positive women.


Assuntos
Citodiagnóstico/estatística & dados numéricos , Detecção Precoce de Câncer/métodos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Triagem/normas , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Colposcopia , Citodiagnóstico/métodos , DNA Viral/análise , DNA Viral/genética , Feminino , Seguimentos , Humanos , México/epidemiologia , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Prognóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia
5.
Gac Med Mex ; 156(2): 132-137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285862

RESUMO

On December 31, 2019, the Chinese health authorities informed the international community, through the mechanisms established by the World Health Organization (WHO), of a pneumonia epidemic of unknown etiology in Wuhan, Hubei Province. The first cases were reported early in that month and were linked to a history of having visited a market where food and live animals are sold. On January 7, 2020, isolation and identification of the culprit pathogen was achieved using next-generation sequencing, while the number of affected subjects continued to rise. The publication of full-genomes of the newly identified coronavirus (initially called 2019-nCoV, now called SARS-CoV2) in public and private databases, of standardized diagnostic protocols and of the clinical-epidemiological information generated will allow addressing the Public Health Emergency of International Concern (PHEIC), declared on January 30 by the WHO. With this document, we intend to contribute to the characterization of the pneumonia epidemic, now designated coronavirus disease (Covid-19) review the strengths Mexico has in the global health concert and invite health professionals to join the preparedness and response activities in the face of this emergency.


El 31 de diciembre de 2019, las autoridades chinas de salud informaron a la comunidad internacional, a través de los mecanismos establecidos por la Organización Mundial de la Salud (OMS), de una epidemia de neumonía con etiología desconocida en Wuhan, provincia de Hubei. Los primeros casos se notificaron a inicios de ese mes y se vincularon al antecedente de visitar un mercado de comida y animales vivos. El 7 de enero de 2020 se logró el aislamiento y reconocimiento del patógeno responsable mediante secuenciación de siguiente generación, mientras el número de afectados continuaba en ascenso. La publicación de genomas completos del nuevo coronavirus identificado (inicialmente denominado 2019-nCoV, ahora designado SARS-CoV2) en bases de datos públicas y privadas, de protocolos diagnósticos estandarizados y de la información clínica epidemiológica generada permitirá atender la Emergencia de Salud Pública de Importancia Internacional (ESPII) declarada el 30 de enero por la OMS. Con este documento pretendemos aportar a la caracterización de la epidemia de neumonía, ahora llamada enfermedad por coronavirus (Covid-19), revisar las fortalezas que tiene México en el concierto de la salud global e invitar a los profesionales de la salud a incorporarse a las actividades de preparación y respuesta ante esta emergencia.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Pneumonia Viral/epidemiologia , COVID-19 , Saúde Global , Humanos , México , Pandemias , Saúde Pública , SARS-CoV-2 , Organização Mundial da Saúde
6.
Gac. méd. Méx ; 156(2): 133-138, mar.-abr. 2020. graf
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1249883

RESUMO

Resumen El 31 de diciembre de 2019, las autoridades chinas de salud informaron a la comunidad internacional, a través de los mecanismos establecidos por la Organización Mundial de la Salud (OMS), de una epidemia de neumonía con etiología desconocida en Wuhan, provincia de Hubei. Los primeros casos se notificaron a inicios de ese mes y se vincularon al antecedente de visitar un mercado de comida y animales vivos. El 7 de enero de 2020 se logró el aislamiento y reconocimiento del patógeno responsable mediante secuenciación de siguiente generación, mientras el número de afectados continuaba en ascenso. La publicación de genomas completos del nuevo coronavirus identificado (inicialmente denominado 2019-nCoV, ahora designado SARS-CoV2) en bases de datos públicas y privadas, de protocolos diagnósticos estandarizados y de la información clínica epidemiológica generada permitirá atender la Emergencia de Salud Pública de Importancia Internacional (ESPII) declarada el 30 de enero por la OMS. Con este documento pretendemos aportar a la caracterización de la epidemia de neumonía, ahora llamada enfermedad por coronavirus (Covid-19), revisar las fortalezas que tiene México en el concierto de la salud global e invitar a los profesionales de la salud a incorporarse a las actividades de preparación y respuesta ante esta emergencia.


Abstract On December 31, 2019, the Chinese health authorities informed the international community, through the mechanisms established by the World Health Organization (WHO), of a pneumonia epidemic of unknown etiology in Wuhan, Hubei Province. The first cases were reported early in that month and were linked to a history of having visited a market where food and live animals are sold. On January 7, 2020, isolation and identification of the culprit pathogen was achieved using next-generation sequencing, while the number of affected subjects continued to rise. The publication of full-genomes of the newly identified coronavirus (initially called 2019-nCoV, now designated SARS-CoV2) in public and private databases, of standardized diagnostic protocols and of the clinical-epidemiological information generated will allow addressing the Public Health Emergency of International Concern (PHEIC), declared on January 30 by the WHO. With this document, we intend to contribute to the characterization of the pneumonia epidemic, now called Corona virus disease (Covid-19) review the strengths Mexico has in the global health concert and invite health professionals to join the preparedness and response activities in the face of this emergency.


Assuntos
Humanos , Pneumonia Viral/epidemiologia , Surtos de Doenças , Infecções por Coronavirus/epidemiologia , Betacoronavirus , Organização Mundial da Saúde , Saúde Pública , Saúde Global , Pandemias , SARS-CoV-2 , COVID-19 , México
7.
J Diet Suppl ; 15(3): 365-371, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28937838

RESUMO

To provide a comprehensive analysis of the literature examining the pros and cons of protein supplementation, various articles on protein supplementation were obtained from Google Scholar, PubMed, and National Center for Biotechnology Information. Over the past few years, protein supplementation has become commonplace for gym-goers as well as for the public. A large segment of the general population relies on protein supplementation for meal replacement, weight reduction, and purported health benefits. These protein supplements have varying pros and cons associated with them, which are often overlooked by the public. This review aims to assimilate existing studies and form a consensus regarding the benefits and disadvantages of protein supplementation. The purported health benefits of protein supplementation have led to overuse by both adults and adolescents. Although the pros and cons of protein supplementation is a widely debated topic, not many studies have been conducted regarding the same. The few studies that exist either provide insufficient evidence or have not employed proper conditions for the conduct of the tests. It should be considered that protein supplements are processed materials and often do not contain other essential nutrients required for the sustenance of a healthy lifestyle. It is suggested that the required protein intake should be obtained from natural food sources and protein supplementation should be resorted to only if sufficient protein is not available in the normal diet.


Assuntos
Dieta Saudável , Proteínas Alimentares/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Animais , Fármacos Antiobesidade/administração & dosagem , Fármacos Antiobesidade/efeitos adversos , Fármacos Antiobesidade/uso terapêutico , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/metabolismo , Proteínas Alimentares/uso terapêutico , Fenômenos Fisiológicos da Nutrição do Idoso , Humanos , Resistência à Insulina , Desenvolvimento Muscular , Obesidade/dietoterapia , Obesidade/metabolismo , Obesidade/prevenção & controle , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/uso terapêutico , Guias de Prática Clínica como Assunto , Treinamento Resistido , Sarcopenia/dietoterapia , Sarcopenia/metabolismo , Sarcopenia/prevenção & controle , Sociedades Médicas , Medicina Esportiva , Fenômenos Fisiológicos da Nutrição Esportiva
8.
J Postgrad Med ; 63(3): 203-205, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28695872

RESUMO

Teratoma of the orbit is rare; very few cases have been published in literature. A case of orbital teratoma in a neonate is presented where the proptosis was massive enough to obscure the eyeball. Clinically, the diagnosis of teratoma was considered. As there was no possibility of salvaging the eye, exenteration of the orbit was done. Orbital teratomas are generally benign. Histopathological examination revealed the features of malignant teratoma.


Assuntos
Neoplasias Orbitárias/patologia , Teratoma/patologia , Humanos , Recém-Nascido , Exenteração Orbitária , Neoplasias Orbitárias/congênito , Neoplasias Orbitárias/cirurgia , Teratoma/congênito , Teratoma/cirurgia
9.
Mol Cell Biomech ; 11(2): 101-11, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25831857

RESUMO

The mass transfer in an eccentric annular region through diffusion by taking blood as a Newtonian fluid with the investigation of oxygen transfer and drug transport to the tissue cells in an eccentric catheterized artery is studied. The region bounded by eccentric circles in x-y plane is mapped conformally to concentric circles in ξ - η plane using a conformal mapping z = λ/1 - ζ. The resulting governing equations are analytically solved by using transformation for the concentration. Numerical computations are carried out to understand the simultaneous effects of absorption parameter and eccentricity on the flow. The observation through the numerical computation reveals that, as absorption parameter and eccentricity enhances, the solute concentration diminishes. This mathematical model provides an insight for physiologists to understand the drug transport to the tissues in various clinical treatments of cardiovascular diseases.


Assuntos
Artérias/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Modelos Cardiovasculares , Oxigênio/metabolismo , Transporte Biológico , Doenças Cardiovasculares/fisiopatologia , Difusão , Portadores de Fármacos , Humanos , Modelos Teóricos
10.
J Parasit Dis ; 37(1): 29-34, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24431537

RESUMO

Hookworm infection was found in the slum area of Eluru, West Godavari District, A.P. which has scheduled caste population. Infection is related to different climatic conditions and socio-economic status of the population. The inhabitants are coolies in agricultural fields and household workers with a poor level of hygiene and sanitation. All the infected positive cases showed Ancylostoma duodenale infection. The prevalence of hookworm infection was 15.6, 17.9 and 14 % in children, 23.5, 27.9 and 20.5 % in adults during summer, rainy and winter seasons respectively. Single species infection was studied in three periods. Out of 264 faecal samples, 128 children (40 males, 32.5 %) and 136 adults (64 men, 25 % and 72 women, 30.5 %) showed helminthic infection in rainy season. Much variation is seen in the prevalence of disease in rainy and winter seasons in all the age groups. The infected individuals were treated with albendazole just after rainy season. Three weeks after antihelminthic treatment, the infection rate among them was lowered; health education also plays a role in reducing the % of infection.

11.
J Conserv Dent ; 14(4): 337-40, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22144798

RESUMO

BACKGROUND: Dental amalgam is the primary direct posterior restorative material used worldwide, but it have certain shortcomings due to the lack of adhesiveness to the cavity. The introduction of the concept of bonded amalgam helped improve the use of amalgam as a restorative material. AIM: Evaluation of the comparative push-out shear bond strength of four types of conventional glass ionomers used to bond amalgam to tooth in simulated class I situations. MATERIALS AND METHODS: FOUR CHEMICAL CURE GLASS IONOMERS ARE USED: GC Fuji I, GC Fuji II, GC Fuji III and GC Fuji VII, and are compared with unbonded amalgam. The push-out bond strength was tested using the Instron Universal Testing Machine at a crosshead speed of 0.5 mm/min. STATISTICAL ANALYSIS: One-way ANOVA and post hoc Bonferroni tests were used to analyze the data. RESULTS: The results showed that the use of glass ionomer to bond amalgam resulted in an increase in the bond strength of amalgam. The Type VII glass ionomer showed the highest bond strength in comparison with the other glass ionomers. CONCLUSIONS: Conventional glass ionomer bonds to amalgam and shows a beneficial increase in the bond strength of the restoration in comparison with unbonded amalgam.

12.
J Conserv Dent ; 14(3): 247-51, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22025827

RESUMO

AIM: The aim of this in vitro study was to compare the shear bond strengths of two different dentin bonding agents with two different desensitizers. MATERIALS AND METHODS: Eighty molars were taken which were ground to expose the dentin. The teeth were divided into two major groups. Each major group was subdivided into four subgroups of 10 samples each. Groups Ia and IIa were treated as dry bonding groups, groups Ib and IIb were treated as a moist bonding groups, groups Ic and IIc were rewetted with Gluma desensitizer, and groups Id and IId were rewetted with vivasens desensitizer. Major group I was treated with Gluma comfort bond and Charisma. Major group II was treated Prime and Bond NT and TPH. The samples were thermo cycled and shear bond test was performed using an Instron machine. The data were analyzed using one-way analysis of variance and Tukey's Honestly significant different test. RESULTS: The results revealed that the specimens rewetted with Gluma desensitizer showed the highest shear bond strength compared to all other groups, irrespective of the bonding agent or composite resin used. CONCLUSIONS: It can be concluded that rewetting with desensitizer provided better bond strength than the other groups.

13.
Radiat Prot Dosimetry ; 144(1-4): 177-81, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21217133

RESUMO

The bubble detector is demonstrated as one of the best suitable neutron detectors for neutron dose rate measurements in the presence of high-intense gamma fields. Immobilisation of a volatile liquid in a superheated state and achieving uniform distribution of tiny superheated droplets were a practical challenge. A compact and reusable bubble detector with high neutron sensitivity has been developed at the Indira Gandhi Centre for Atomic Research by immobilising the superheated droplets in a suitable polymer matrix. Two types of bubble detectors have been successfully developed, one by incorporating isobutane for measuring fast neutron and another by incorporating Freon-12 for both fast and thermal neutron. The performance of the detector has been tested using 5 Ci Am-Be neutron source and the results are described.


Assuntos
Nêutrons , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Radiometria/instrumentação , Amerício/análise , Berílio/análise , Calibragem , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Raios gama , Temperatura Alta , Humanos , Teste de Materiais , Centrais Nucleares , Exposição Ocupacional , Polímeros/química , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Radiometria/métodos
14.
Am J Psychiatry ; 168(3): 286-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21205805

RESUMO

OBJECTIVE: This study examined the effect of medication nonadherence on the return of positive symptoms among recent-onset schizophrenia patients. METHOD: Three sets of operational criteria for medication nonadherence with differing levels of severity were compared for their ability to predict relapse. Explicit operational criteria are provided with the hope that they will be adopted by others. Psychotic symptoms were prospectively rated on a frequent basis, and systematic criteria were applied using a computer scoring program to identify periods of psychotic symptom return. In addition, a specialized statistical survival analysis method, optimal for examining risk periods and outcomes that can recur during the follow-up assessment, was used. RESULTS: As hypothesized, medication nonadherence robustly predicted a return of psychotic symptoms during the early phase of schizophrenia (hazard ratios=3.7-28.5, depending on the severity of nonadherence). CONCLUSIONS: Even brief periods of partial nonadherence lead to greater risk of relapse than what is commonly assumed. Patients in the early phase of schizophrenia should be cautioned about the possible consequences of partial or relatively brief periods of antipsychotic medication nonadherence.


Assuntos
Adesão à Medicação/psicologia , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/prevenção & controle , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Prevenção Secundária
15.
Radiat Prot Dosimetry ; 144(1-4): 427-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21044995

RESUMO

A phoswich detector, housed inside a low background steel room, coupled with a state-of-art pulse shape discrimination (PSD) electronics is recently established at Radiological Safety Division of IGCAR for in vivo monitoring of actinides. The various parameters of PSD electronics were optimised to achieve efficient background reduction in low-energy regions. The PSD with optimised parameters has reduced steel room background from 9.5 to 0.28 cps in the 17 keV region and 5.8 to 0.3 cps in the 60 keV region. The Figure of Merit for the timing spectrum of the system is 3.0. The true signal loss due to PSD was found to be less than 2 %. The phoswich system was calibrated with Lawrence Livermore National Laboratory realistic chest phantom loaded with (241)Am activity tagged lung set. Calibration factors for varying chest wall composition and chest wall thickness in terms of muscle equivalent chest wall thickness were established. (241)Am activity in the JAERI phantom which was received as a part of IAEA inter-comparison exercise was estimated. This paper presents the optimisation of PSD electronics and the salient results of the calibration.


Assuntos
Pulmão/patologia , Imagens de Fantasmas , Amerício/análise , Calibragem , Césio/química , Eletrônica , Desenho de Equipamento , Humanos , Iodetos/química , Pulmão/efeitos da radiação , Centrais Nucleares , Fótons , Iodeto de Sódio/química , Aço , Tórax/patologia
16.
J Conserv Dent ; 13(3): 116-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21116383

RESUMO

AIM: To evaluate the effect of surface moisture on dentinal tensile bond strength. MATERIALS AND METHODS: Forty freshly extracted caries free, unrestored human mandibular molars were selected. The occlusal surfaces of each tooth were ground to prepare flat dentin surfaces at a depth of 1.5 mm. Following acid etching with 37% phosphoric acid for 15 sec, they were randomly grouped, with ten specimens in each: Group I - Over wet, Group II - Blot dry, Group III- One second dry, Group IV- Over dry. Each group was treated with a single bond adhesive system (3M ESPE) as per manufacturer's instructions. Blocks or cylinders of composite resin were built up using Teflon mould and cured. Tensile bond strengths were tested using Instron universal testing machine. The results were statistically analyzed. RESULTS: The mean tensile bond strength values of group II, Blot dry was highest and statistically significant (P<0.001). CONCLUSION: After acid etching and rinsing blot drying provided consistently better bond strength.

17.
J Conserv Dent ; 13(3): 132-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21116387

RESUMO

AIMS/OBJECTIVES: This in vitro study was designed to measure and compare the temperature rise in the pulp chamber with different light curing units. MATERIALS AND METHODS: The study was done in two settings-in-vitro and in-vivo simulation. In in-vitro setting, 3mm and 6mm acrylic spacers with 4mm tip diameter thermocouple was used and six groups were formed according to the light curing source- 3 Quartz-Tungsten-Halogen (QTH) units and 3 Light-Emitting-Diode (LED) units. For the LED units, three modes of curing like pulse-cure mode, fast mode and ramp mode were used. For in-vivo simulation, 12 caries free human third molar tooth with fused root were used. K-type thermocouple with 1 mm tip diameter was used. Occlusal cavity was prepared, etched, rinsed with water and blot dried; bonding agent was applied and incremental curing of composite was done. Thermal emission for each light curing agent was noted. RESULTS: Temperature rise was very minimal in LED light cure units than in QTH light cure units in both the settings. Temperature rise was minimal at 6mm distance when compared to 3 mm distance. Among the various modes, fast mode produces the less temperature rise. Temperature rise in all the light curing units was well within the normal range of pulpal physiology. CONCLUSION: Temperature rise caused due to light curing units does not result in irreversible pulpal damage.

18.
Contemp Clin Dent ; 1(4): 210-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22114422

RESUMO

OBJECTIVE: This study aimed at qualitatively evaluating the remineralization potential of casein phosphopeptide amorphous calcium phosphate on artificial early enamel lesions in an ex-vivo scenario by observing the treated tooth surface using a scanning electron microscope (SEM). MATERIALS AND METHODS: This randomized study was conducted on 10 subjects undergoing orthodontic treatment with premolar extraction as part of their treatment. Artificial white lesions were created with the application of 37% phosphoric acid for 20 mins. Teeth were then divided into two groups: one experimental and the other control. Customised orthodontic band with a window was luted with intermediate restorative material in the experimental group whereas in the control group, band without a window was luted. The casein phosphopeptide amorphous calcium phosphate (GC TOOTH MOUSSE) paste was then applied on the window region of the experimental group for 3 mins thrice daily after meals for 14 days, whereas no paste was applied in the control group. After 14 days, teeth were extracted and viewed under an SEM. RESULTS: The study groups showed remineralization of the lesions as compared with the control group in most of the samples. CONCLUSION: Casein phophopeptide could significantly remineralize the artificial enamel lesions in vivo.

19.
Indian J Dent Res ; 20(1): 17-20, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19336854

RESUMO

AIM: The aim of this study was to evaluate the surface tension and pH of five different vehicles that are used as potential agents to mix calcium hydroxide in root canal treatments and to compare them with the final surface tension and pH of calcium hydroxide mixed with these vehicles. MATERIALS AND METHODS: The study was carried out in two phases. In Phase I, the surface tension and pH of five vehicles (distilled water, saline, anesthetic solution, chlorhexidine, and glycerin) were evaluated using a Du Nuoy Tensiometer and a pH Meter. In Phase II, a predetermined amount of calcium hydroxide was mixed with the individual vehicles and the surface tension and pH was determined. In each group, seven samples were evaluated. RESULTS: Among the individual vehicles, chlorhexidine had the least surface tension values (39.8+1.1 dynes/cm). Among the various calcium hydroxide mixtures, calcium hydroxide with chlorhexidine showed the least surface tension values (36.4+1.1 dynes/cm). All the vehicles showed an acidic pH ranging from 5 to 6.5. There was a significant increase in the pH values with the addition of calcium hydroxide to the respective vehicles. The calcium hydroxide mixtures had an alkaline pH ranging from 9 to 11.5; the highest pH was observed for calcium hydroxide mixed with distilled water and saline (11.5+0.2). CONCLUSION: The surface tension and pH of the vehicles directly influenced the surface tension and pH of the calcium hydroxide mixtures. Chlorhexidine was found to be a better vehicle for calcium hydroxide when used as an intracanal medicament.


Assuntos
Hidróxido de Cálcio/química , Irrigantes do Canal Radicular/química , Concentração de Íons de Hidrogênio , Veículos Farmacêuticos , Tensão Superficial
20.
J Conserv Dent ; 12(1): 37-40, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20379439

RESUMO

The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and technically challenging. This case report presents the treatment of a mandibular first molar with five root canals, of which three were located in the mesial root. A third canal was found between the mesiobuccal and mesiolingual root canals. The morphological pattern of separate apical terminations of three mesial root canals with separate orifices, as manifested in this case, is a rare one.

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