Dosimetric properties of UV irradiated calcium co-doped borate glass-ceramic

The thermoluminescence (TL) response of Dy and Li doped 20CaB(4)O(7)-80CaB(2)O(4) (Wt%) glass-ceramic irradiated with ultraviolet (UV) radiation was studied. In order to act as TL activator ions, the Dy and Li ions were included in the matrix during the melting process to increase its TL efficiency. A single crystalline CaB2O4 phase was present in the glass-ceramic as determined by X-ray diffraction (XRD). The glass-ceramic 20CaB(4)O(7)-80CaB(2)O(4):Dy,Li wt% (named 20CBO7:Dy,Li) is a newly prepared TL material. Its thermoluminescent dosimetric characteristics have shown a linear response under UV radiation exposure and a good TL signal reproducibility, thus proving to be a promising material for using as an ultraviolet radiation dosimeter. (C) 2007 Elsevier B.V. All rights reserved.

Controle de qualidade e dosimetria em equipamentos de tomografia computadorizada

OBJETIVO: Avaliação de condições dos equipamentos e dosimetria em setores de tomografia computadorizada utilizando protocolos de cabeça, abdome e coluna lombar em pacientes adultos (em três equipamentos distintos) e pediátricos com até um ano e meio de vida (em um dos equipamentos avaliados). MATERIAIS E MÉTODOS: Foram estimados o índice de dose em tomografia computadorizada e a dose média em cortes múltiplos, em exames com pacientes adultos, em três distintos equipamentos. Ainda foram estimadas as doses na superfície de entrada e as doses absorvidas em exame de cabeça para pacientes adultos e pediátricos em um dos equipamentos avaliados. RESULTADOS: Foram realizados testes de controle de qualidade, mecânicos, demonstrando que os equipamentos satisfazem as especificações de uso estabelecidas pelas normas vigentes. Os resultados da dosimetria mostraram que valores de dose média em cortes múltiplos excederam em até 109,0% os valores de níveis de referência, apresentando consideráveis variações entre os equipamentos avaliados neste estudo. As doses absorvidas obtidas com protocolos pediátricos são inferiores aos de pacientes adultos, apresentando redução de até 51,0% na tireoide. CONCLUSÃO: Neste estudo foram avaliadas as condições de operação de três equipamentos tomográficos, estabelecendo quais parâmetros devem ser trabalhados para a implantação de um programa de controle de qualidade nas instituições onde esta pesquisa foi desenvolvida.

A complete dosimetric characterization of two Sr-90-Y-90 dermatologic applicators

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pulmonary tuberculosis: Hematology, serum biochemistry and the relation with the disease duration

The aim of the present study was to analyze the relationship between hematological and biochemical parameters and tuberculosis process activity time according to clinical complaint duration. It was a retrospective study analyzing medical records from 80 pulmonary tuberculosis patients at Botucatu Medical School University Hospital ( Botucatu, São Paulo State, Brazil), who were divided into 2 groups according to clinical complaint duration: Group 1 ( G1) - up to three months; Group 2 ( G2) - over three months. Parameters included: age, gender, bacilloscopy, erythrocyte sedimentation rate ( ESR), platelet count, alpha1-globulin, alpha2-globulin, gamma globulin, mucoprotein, alpha1-acid glycoprotein values, and the presence of risk factors such as smoking, alcoholism, drug addiction, sexual promiscuity, contact with tuberculosis carriers, and previous treatment. Groups were compared by calculating t and p, and Chi-square (X-2) and p. Comparisons revealed a tendency towards smoking with a higher frequency of smokers in G1 ( 0.05< p< 0.10). G1 also tended to present greater platelet values than G2 ( 0.05< p< 0.10) and presented significantly higher ESR values than G2 ( p< 0.05). Other factors did not show any significantly different behavior between groups ( p> 0.05). A correlation was found between ESR, platelet count, smoking and less than three months clinical duration.

Cytokines and acute-phase serum proteins as markers of inflammatory regression during pulmonary tuberculosis treatment

Tuberculosis is still increasing and was declared a worldwide sanitary emergency by the World Health Organization (WHO) in 1995. Its control is difficult due to long treatment duration and lack of markers of treatment success or failure. Cytokines such as IFN-gamma and TNF-alpha, a central factor in immune response against Mycobacterium tuberculosis, are responsible for the interaction between T lymphocytes and the infected macrophage and are also produced during this interaction. As proinflammatory cytokines have a close relationship with mycobacteria clearance, in fact even preceding it, they could be used as markers for inflammatory activity and response to treatment. Proinflammatory cytokines act in the liver and stimulate a strong local and systemic acute-phase response as a result of homeostatic and physiological responses also induced by them. Acute-phase proteins produced by cytokine activity are useful diagnostic markers that could also be used to monitor treatment response as they can be serially quantified. The objective of this study was to evaluate IFN-gamma, TNF-alpha, IL-10 and TGF-beta production in supernatant of peripheral blood mononuclear cell (PBMC) and monocyte (MO) cultures, as well as serum acute-phase response through total protein, albumin, globulin, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP), and erythrocyte sedimentation rate (ESR) as regression markers of inflammatory response during pulmonary tuberculosis treatment. Twenty blood donors (G1) from the Blood Bank at Botucatu School of Medicine's University Hospital (BSM-UH) were evaluated once and 28 pulmonary tuberculosis patients (G2): 13 from BSM-UH and 15 from the Bauru State Health Secretariat. Patients were evaluated at three moments of treatment: before (M1), at three months (M2), and at the end (M3). Cytokines were determined in 20ml of peripheral blood (ELISA), with or without activation: lipopolysaccharide (LPS) for MO culture and phytohemagglutinin (PHA) for PBMC culture. Acute-phase protein behavior in G2 throughout treatment was: Globulins: M1> M2, M1> M3 (rho < 0.001); CRP: M1> M2> M3 (.< 0.001); AGP for men: M1> M2, M1> M3 (rho < 0.001); ESR for men: M1> M2, M1> M3 (rho < 0.0016) and for women: M1> M2 (.< 0.025). Comparison between cytokine levels found in supernatant of MO and PBMC cultures, with and without stimulus, in G1 and G2 during treatment showed: TNF-alpha (with/ without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); (without LPS) at M3: G2> G1 (rho < 0.001), (with LPS) at M3: G2> G1 (rho < 0.028); IFN-. (with and without PHA) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); IL-10 (with and without LPS) at M1: G2> G1; at M2: G2> G1; at M3: G2> G1 (rho < 0.001); TGF-beta (with and without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001), (without LPS) at M3: G2> G1 (rho < 0.001). In G2, all cytokines in supernatant of MO and PBMC cultures, with and without stimulus, showed: M1> M2> M3 (rho < 0.01). Levels of globulins, CRP, AGP, and ESR in patients with pulmonary tuberculosis before treatment (M1) were significantly higher than reference values, suggesting their use as diagnostic markers and indicators of treatment. The CRP decreasing values along treatment could be taken as a marker of the regression of inflammatory process and of response to treatment in patients with pulmonary tuberculosis.Regarding cytokines, there was significant increase in TNF-alpha, IFN-gamma, IL-10, and TGF-alpha levels before and at three months treatment, with and without stimulus; in TNF-a and IL-10 lvels, with and without stimulus, as well as in TGF-alpha levels without stimulus at six months. Patients had higher levels of all studied cytokines than controls before treatment, and these values decreased along treatment. In this study, pulmonary tuberculosis patients showed a Th0 cytokine profile before treatment, with the production of both Th1 (IFN-gamma) and Th2 (IL-10) cytokines, in addition to TNF-alpha inflammatory and TGF-alpha regulatory and fibrosis-inducer cytokines. At the end of treatment, all had evolved to Th2 profile, probably in an attempt to reduce the harmful effects of the proinflammatory activity of the Th1 cytokine profile and of the still above-normal levels of TNF-alpha. The high levels of TGF-alpha, also found in these patients, are related to its important role in the extracellular matrix deposition and fibrosis induction that characterize tuberculosis healing process. IFN-gamma was the only cytokine reaching normal levels at the end of treatment, which suggests its use as a marker of response to treatment.

Citocinas e proteínas de fase aguda do soro como marcadores de regressão da resposta inflamatória ao tratamento da tuberculose pulmonar

OBJETIVO: Analisar o padrão de citocinas pró- e antiinflamatórias e da resposta de fase aguda (RFA) como marcadores de resposta ao tratamento da tuberculose pulmonar. MÉTODOS: Determinação dos níveis de interferon-gama (IFN-γ), tumor necrosis factor-alpha (TNF-α, fator de necrose tumoral-alfa), interleucina-10 (IL-10) e transforming growth factor-beta (TGF-β, fator transformador de crescimento-beta), pelo método ELISA, em sobrenadante de cultura de células mononucleares do sangue periférico e monócitos, assim como dos níveis de proteínas totais, albumina, globulinas, alfa-1-glicoproteína ácida (AGA), proteína C reativa (PCR) e velocidade de hemossedimentação (VHS) em 28 doentes com tuberculose pulmonar, em três tempos: antes (T0), aos três meses (T3) e aos seis meses (T6) de tratamento, em relação aos controles saudáveis, em um único tempo. RESULTADOS: Os pacientes apresentaram valores maiores de citocinas e RFA que os controles em T0, com diminuição em T3 e diminuição (TNF-α, IL-10, TGF-β, AGA e VHS) ou normalização (IFN-γ e PCR) em T6. CONCLUSÕES: PCR, AGA e VHS são possíveis marcadores para auxiliar no diagnóstico de tuberculose pulmonar e na indicação de tratamento de indivíduos com baciloscopia negativa; PCR (T0 > T3 > T6 = referência) pode também ser marcador de resposta ao tratamento. Antes do tratamento, o perfil Th0 (IFN-γ, IL-10, TNF-α e TGF-β), indutor de e protetor contra inflamação, prevaleceu nos pacientes; em T6, prevaleceu o perfil Th2 (IL-10, TNF-α e TGF-β), protetor contra efeito nocivo pró-inflamatório do TNF-α ainda presente. O comportamento do IFN-γ (T0 > T3 > T6 = controle) sugere sua utilização como marcador de resposta ao tratamento.

Clinical presentation and salivary gland histopathology of paediatric primary Sjogren's syndrome

ObjectiveExplore the presentation, diagnostic criteria and exocrine gland histopathology of paediatric primary Sjogren's syndrome (PPSjS).MethodsA case series of 8 children is reported and American-European Consensus Group (AECG-2002) criteria were examined, as well as minor labial salivary and lachrymal gland biopsies, which were scored by a pathologist blinded to outcome. For all cases, connective tissue diseases and parotid-related infectious disease were excluded.ResultsAge at onset varied from 5-13 years old; 6 were females, all followed from diagnosis up to the last visit (1-10 years). The main features at presentation were recurrent tender parotid swelling and sialectasis imaging, with decreased salivary function assessed by Tc-99 scintigraphy. Mild sicca symptoms were observed in 4/8 cases. Systemic features, including fatigue, myalgia, arthritis, tenosynovitis, joint contractures, transient Raynaud's and high ESR, were recorded at onset. Autoantibody profile was unremarkable for diagnosis, while lymphocytic infiltration of labial salivary glands and sialectasis were observed in all biopsies (8/8). In lachrymal glands, massive lymphocytic infiltration and lymphocytic gastritis were observed during complementary assessment. Flares were treated with low dose steroids and long-term use of hydroxychloroquine (5/8), although only 318 fulfilled AECG-2002 diagnostic criteria, throughout the disease course.ConclusionPPSjS is rare, slowly progressive and its early presentation is variable. Standardised diagnostic algorithms should include recurrent parotid swelling and early diagnosis should rely mostly on salivary and lachrymal gland histopathology in this age group.

Preliminary Criteria for Global Flares in Childhood-Onset Systemic Lupus Erythematosus

Objective. To develop widely acceptable preliminary criteria of global flare for childhood-onset systemic lupus erythematosus (cSLE).Methods. Pediatric rheumatologists (n = 138) rated a total of 358 unique patient profiles with information about the cSLE flare descriptors from 2 consecutive visits: patient global assessment of well-being, physician global assessment of disease activity (MD-global), health-related quality of life, anti-double-stranded DNA antibodies, disease activity index scores, protein: creatinine (P:C) ratio, complement levels, and erythrocyte sedimentation rate (ESR). Based on 2,996 rater responses about the course of cSLE (baseline versus followup), the accuracy (sensitivity, specificity, and area under the receiver operating characteristic curve) of candidate flare criteria was assessed. An international consensus conference was held to rank these candidate flare criteria as per the American College of Rheumatology recommendations for the development and validation of criteria sets.Results. The highest-ranked candidate criteria considered absolute changes (Delta) of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) or British Isles Lupus Assessment Group (BILAG), MD-global, P:C ratio, and ESR; flare scores can be calculated (0.5 x Delta SLEDAI + 0.45 x Delta P:C ratio + 0.5 x Delta MD-global + 0.02 x Delta ESR), where values of >= 1.04 are reflective of a flare. Similarly, BILAG-based flare scores (0.4 x Delta BILAG + Delta 0.65 x Delta P:C ratio + 0.5 + Delta MD-global + 0.02 x Delta ESR) of >= 1.15 were diagnostic of a flare. Flare scores increased with flare severity.Conclusion. Consensus has been reached on preliminary criteria for global flares in cSLE. Further validation studies are needed to confirm the usefulness of the cSLE flare criteria in research and for clinical care.

Consenso em reumatologia pediátrica: parte I - definição dos critérios de doença inativa e remissão em artrite idiopática juvenil/artrite reumatóide juvenil

Não há critérios universalmente aceitos para a remissão clínica em artrite idiopática juvenil/artrite reumatóide juvenil (AIJ/ARJ). OBJETIVO: formar consenso sobre estes critérios. MÉTODOS: foi utilizado um inquérito pelo método Delphi para reunir os critérios vigentes e utilizados por especialistas em reumatologia pediátrica (RP) no mundo todo. A análise dos resultados constituiu a base para uma Consensus Conference utilizando a nominal group technique (NGT) para alcançar o consenso nas questões não resolvidas após a análise dos questionários deste inquérito. Cento e trinta RP de 34 países responderam ao inquérito e 20 RP de nove países elegeram os critérios durante dois dias, em processo de discussão estruturada, para formar consenso pela NGT. RESULTADOS: os critérios de doença inativa deveriam incluir: 1) nenhuma articulação com artrite em atividade; 2) ausência de febre, rash, serosite, esplenomegalia ou linfadenopatia generalizada atribuída à AIJ/ARJ; 3) ausência de uveíte em atividade; 4) VHS ou PCR negativas (se ambos forem testados, ambos devem ser normais); 5) a avaliação global pelo médico deve indicar o melhor escore possível, indicando doença inativa. CONCLUSÕES: de acordo com o voto de consenso, seis meses contínuos de doença inativa são necessários para se considerar um paciente em estado de remissão com medicação; 12 meses contínuos de doença inativa e sem medicação são necessários para considerar um paciente em estado de remissão sem medicação. O critério para remissão sem medicação deve prever com acurácia de 95% a probabilidade inferior a 20% de recaída em cinco anos.

Análise histológica em tecido epitelial sadio de ratos Wistar (in vivo) irradiados com diferentes intensidades do ultrassom

CONTEXTUALIZAÇÃO: O Ultrassom (US) é um dos recursos físicos amplamente utilizado e pesquisado nos tratamentos de fisioterapia. Sabe-se que diante de uma escassa literatura sobre efeitos do US em tecidos sadios, muitos profissionais fisioterapeutas acabam realizando aplicações infundadas de métodos e parâmetros. OBJETIVO: Avaliar possíveis alterações histológicas e morfométricas do tecido sadio in vivo de ratos Wistar irradiados com diferentes intensidades de US. MÉTODOS: Trinta ratos da linhagem Wistar, distribuídos aleatoriamente em cinco grupos de seis animais cada foram tratados na região dorsal do lado direito numa área de 4cm². O lado esquerdo serviu como controle. O tratamento foi feito durante quatro dias com 2 minutos de irradiação. Verificou-se a intensidade de saída com dosímetro de precisão antes das aplicações. Analisou-se a histologia e a morfometria por meio do software Image Tool. RESULTADOS: Observou-se um discreto infiltrado inflamatório e adelgaçamento das fibras da derme, principalmente dos grupos irradiados com 1.5 e 2W/cm². Notou-se também um aumento na espessura da epiderme nas amostras dos animais irradiados. Para avaliar os resultados quantitativos, utilizou-se como análise estatística ANOVA one way e o teste post hoc de Tukey. Na espessura da epiderme, obtiveram-se diferenças significativas entre grupo controle e os grupos irradiados com 1.0, 1.5 e 2.0W/cm². CONCLUSÃO: Sob ação do US nas doses maiores houve alterações na epiderme e derme, respectivamente, o aumento da espessura e proliferação com adelgaçamento das fibras colágenas, o que alerta para possíveis implicações do uso do US em estética.

In vivo determination of incorporated activity of Tc-99(m)-MDP in bone tissue

In vivo determination of the incorporated activity of Tc-99(m)-MDP (methylene diphosphonate) in bone tissue by means of a scintillation camera requires calibration of the device. This can be carried out by using an anthropomorphic physical phantom. In this work, a new human tibia and fibula phantom is presented to estimate incorporated activity to bone tissue. A tibia and a fibula, taken from a real skeleton, were used to develop the phantom. Images were acquired of the legs of 65 volunteers at different times of incorporation (minimum of 120 and maximum of 2500 min after injection) and count rates of such a region were obtained by means of a computer program. The calibration factor obtained was then used to assess the activity in the two bents. The final result is 0.4995 kBq per cpm for technetium. The proposed method can be used both for radiation protection purposes and for metabolism studies.

Thermoluminescence measurements of entrance surface skin dose in exams of dog's chest in veterinary radiology

This study aims to determine the entrance surface skin doses in dogs (with suspected pulmonary metastasis) submitted to chest X-rays using the technique of thermoluminescence (TL) dosimetry. Twenty seven radiologic exams of dogs of different breed and sizes were performed. The radiation doses were assessed using thermoluminescent dosimeters of calcium sulphate doped with dysprosium (CaSO(4):Dy) produced at Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN). The entrance surface skin dose range evaluated in this type of procedure was between 0.43 mGy to small size dogs and 4.22 mGy to big size dogs with repeated exams. The obtained results indicate that is extremely important the assessment of radiation doses involved in veterinary diagnostic radiology procedures, to evaluate the delivered doses to the animals, to be used as a parameter in the individual monitoring of pet's owners, who assist the animal positioning, and to protect occupationally exposed workers at the Veterinary Radiology Clinics. (C) 2010 Elsevier Ltd. All rights reserved.

Structural and thermal characterization of dioctadecyldimethylammonium bromide dispersions by spin labels

Dioctadecyldimethylammonium bromide (DODAB) dispersions obtained by simply mixing the amphiphile in water, and by bath-sonication, were investigated by electron spin resonance (ESR) of stearic acids and their methyl ester derivatives, labeled at the 5th and 16th carbons of the acyl chain. The ESR spectra indicate that the non-sonicated dispersions are formed mainly by one population of DODAB vesicles, either in the gel (T < T-m) or in the liquid-crystalline (T > T-m) state. Around T-m there is a co-existence of the two phases, with a thermal hysteresis of about 3.2 degreesC. In sonicated DODAB dispersions, spin labels indicate two different environments even for temperatures far below T-m: one similar to that obtained with non-sonicated samples, a gel phase, and another one in the liquid-crystalline state. The fluid phase domain present below T-m could correspond to either the periphery of bilayer fragments, reported to be present in sonicated DODAB dispersions, or to high curvature vesicles. (C) 2001 Elsevier B.V. Ireland Ltd. All rights reserved.

New layered double hydroxides intercalated with substituted pyrroles. 1. In situ polymerization of 4-(1H-pyrrol-1-yl)benzoate

The two-dimensional hybrid organic-inorganic materials Zn-2-Cr and Zn-2-Al-LDHs (Layered Double Hydroxides) containing 4-(1H-pyrrol-1yl)benzoate anions as the interlayer anions were synthesized by the co-precipitation method at constant pH followed by subsequent hydrothermal treatment for 72 h. The materials were characterized by PXRD, C-13 CP-MAS NMR, ESR, TGA, and TEM. The basal spacing found by the X-ray diffraction technique is coincident with the formation of bilayers of the intercalated anions. Solid-state C-13 NMR and ESR data strongly suggest the partial in situ polymerization of the 4-(1H-pyrrol-1yl)benzoate anions during coprecipitation. (c) 2006 Elsevier Ltd. All rights reserved.

New layered double hydroxides intercalated with substituted pyrroles. 2. 3-(Pyrrol-1-yl)-propanoate and 7-(pyrrol-1-yl)-heptanoate LDHs

We report the synthesis and characterization of organic-inorganic hybrid materials: Zn-2-Al-LDHs (layered double hydroxides) containing 3-(1H-pyrrol-1-yl)-propanoate and 7-(1H-pyrrol-l-yl)-heptanoate as the interlayer anions. The LDHs were synthesized by the co-precipitation method at constant pH followed by hydrothermal treatment for 72 h. The materials were characterized by PXRD, C-13 CP-MAS NMR, TGA, and ESR. The basal spacing found by PXRD technique is coincident with the formation of bilayers of the intercalated anions. The solid state C-13 NMR showed that the interlayered anions remain identical after intercalation. ESR data suggest that the monomers connect each other in a limited number of guests when a thermal treatment is applied. The inorganic LDH sheets delay the temperature of degradation of the monomers. (c) 2006 Elsevier Ltd. All rights reserved.