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1.
Braz J Biol ; 83: e277515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422270

RESUMO

The consumption of products with high nutritional value and antioxidant capacity has increased notably in recent years. Due to health problems such as triglycerides and cardiovascular problems, its use is becoming reduced. So that, chia (Salvia hispánica) and sachatomate (Cyphomandra betacea) have gained interest as an alternative to develop nutraceutical products, compared to conventional products. The objective of the study was to determine the effect of the partial substitution of mango (Mangifera indica) and ground chia (Salvia hispánica) on the antioxidant capacity in the elaboration of nectar based on Sachatomate. The physicochemical characteristics were determined where sample 11 complies with the established parameters: 13.4° Brix, pH 4.323, 0.354 of C6-H8-O7 and viscosity 3967.3 mPas, according to the NTP 203.110 standard. Regarding the antioxidant capacity, sample 12 was the most optimal, according to the DPPH method, it has been determined 104.3 micromoles Trolox equivalents; according to the ABTS method, it was determined with an antioxidant content of 187.4 micromoles Trolox equivalents. Regarding the proximal chemical evaluation, sample 12 was determined to be the most suitable with a moisture percentage of 87.45%, ash 0.32%, crude fiber 0.09%, fat 0.10%, protein 0.45% and carbohydrates 11.59%. Concluding that substituting sachatomate and ground chia significantly influences the antioxidant capacity, increasing to 104.3 and 187.4 micromoles Trolox equivalents, determined by both methods, indicates that nectar consumption can be used to improve the health of consumers.


Assuntos
Antioxidantes , Mangifera , Antioxidantes/química , Néctar de Plantas , Suplementos Nutricionais , Sementes
2.
Braz J Biol ; 83: e274986, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37820210

RESUMO

Functional beverages with added health benefits are popular among peoples and athletes because they help them recover faster from intense workouts and perform better overall. This research set out to determine how well heat-treated stem juice from Oxalis tuberosa Mol. "oca" and fruit juice from Gaultheria glomerata (Cav.) Sleumer "laqa-laqa" performed as an antioxidant in a functional drink. The "oca" stems and the "laqa-laqa" fruit were collected to obtain the juice. For this study, 30 semi-trained panellists used sensory evaluation to rate four treatments (Bo, B1, B2, and B3) with varying quantities of "oca" and "laqa-laqa" juice. The results concluded that the treatment B2, which included 300 ml of "oca" stem juice, 800 ml of "laqa-laqa" juice, 1000 ml of treated water, and 220 g of refined sugar, was given the highest score after a physicochemical evaluation of its colour, smell, taste, and overall appearance. Similarly, the results showed that the protein content increased by 1.38%, the fat content by 1.08%, the moisture percentage by 99.5%, the ash content by 1.82%, and the carbohydrate content by 6.22% after B2 treatment. Similarly, results revealed significant enhancement in antioxidant profiling such as total polyphenols: 1825 mg of gallic acid/100 g and antioxidant Activity: 89.56% µmol of trolox /100 g. In conclusion, due to its high energy content and antioxidant activity, it may be a viable nutritional option for athletes who engage in rigorous, frequent physical exertion.


Assuntos
Antioxidantes , Gaultheria , Humanos , Antioxidantes/análise , Frutas/química , Gaultheria/metabolismo , Temperatura Alta , Bebidas/análise
3.
J Radiol Prot ; 42(3)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940166

RESUMO

The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for pediatric interventional cardiology (IC) procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study was conducted in the framework of the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the program was focused on pediatric IC. Dose data from diagnostic and therapeutic procedures were collected between December 2020 and December 2021. Regional DRLs were set as the third quartile of patient dose data (kerma area product) collected in 18 hospitals from 10 countries in an initial sample of 968 procedures. DRLs were set for four age bands and five weight ranges. The values obtained for the four age bands (<1 yr, 1 to <5 yr, 5 to <10 yr and 10 to <16 yr) were 2.9, 6.1, 8.8 and 14.4 Gy cm2for diagnostic procedures, and 4.0, 5.0, 10.0 and 38.1 Gy cm2for therapeutic procedures, respectively. The values obtained for the five weight bands (<5 kg, 5 to <15 kg, 15 to <30 kg, 30 to <50 kg and 50 to <80 kg) were 3.0, 4.5, 8.1, 9.2 and 26.8 Gy cm2for diagnostic procedures and 3.7, 4,3, 7.3, 16.1 and 53.4 Gy cm2for therapeutic procedures, respectively. While initial data were collected manually as patient dose management systems (DMSs) were not available in most of the hospitals involved in the program, a centralized automatic DMS for the collection and management of patient dose indicators has now been introduced and is envisaged to increase the sample size. The possibility of alerting on high dose values and introducing corrective actions will help in optimization.


Assuntos
Cardiologia , Níveis de Referência de Diagnóstico , Cardiologia/métodos , Criança , Fluoroscopia , Humanos , América Latina , Doses de Radiação , Radiografia Intervencionista/métodos , Radiologia Intervencionista , Valores de Referência
4.
Neumol. pediátr. (En línea) ; 15(4): 484-490, 2020. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-1146395

RESUMO

Cystic Fibrosis is a multisystemic inherited disease that requires ongoing care by multidisciplinary teams. The objective of this study is to describe changes on nutrition and lung function in a cohort of patients in a Cystic Fibrosis (CF) Care Center at the Hospital Infantil Universitario San José in Bogotá (HIUSJ), between 2010 and 2013.Is a descriptive study in a cohort of CF patients during four years of follow-up. The quantitative variables were described using medians and interquartile ranges, and the qualitative variables with absolute frequencies and percentages. Descriptive statistics was used to summarize the findings. Of the 63 patients in the initial group, 47 (74.6%) completed the follow-up time. The age range was between 3 to 30 years. The median BMI increased as follows: 17.9 (RIQ: 12.5-25.6) in 2010, 18.6 (RIQ: 12.9-24.8) in 2011, 18.9 RIQ (13.6-26.5) in 2012 and 19.0 (RIQ: 13.5-25.8) in 2013, with lower values in men. The forced expiratory volume in the first second (FEV1) at admission was classified as severe (FEV1 <40%) in 7.1%, moderate (FEV1 40-69%) in 35.7%, mild (FEV1 70-79%) in 7.1% and as normal (FEV1> 80%) in 50%. It is concluded that during the 4 years of follow-up at the HIUSJ CF Center there is an improvement in BMI and a deterioration in lung function in the whole group. The importance of establishing more reference centers to improve clinical outcomes and of implement a National registry to follow up over time are highlighted.


La fibrosis quística es una enfermedad hereditaria, multisistémica, cuyo manejo continuo requiere de equipos multidisciplinarios de salud. El objetivo de este trabajo es describir la evolución nutricional y de la función pulmonar en una cohorte de pacientes en el centro de atención integral de la fibrosis quística (FQ), del Hospital Infantil Universitario San José de Bogotá (HIUSJB), entre 2010 y 2013. Estudio descriptivo, en una cohorte de pacientes, en seguimiento durante cuatro años. Las variables cuantitativas fueron descritas mediante medianas y rangos intercuartílicos y las cualitativas con frecuencias absolutas y porcentajes. De los 63 pacientes del grupo inicial, 47 (74.6%), completaron el tiempo de seguimiento. El rango de edad fue de 3 a 30 años. La mediana del IMC (índice de masa corporal) se incrementó así: 17.9 (RIQ:12.5-25.6) en el 2010, 18.6 (RIQ:12.9-24.8) en el 2011, 18.9 ( RIQ(13.6-26.5) en el 2012 y 19.0 (RIQ:13.5-25.8) en el 2013, con menores valores en los hombres. El volumen espiratorio forzado en el primer segundo (VEF1) al ingreso fue clasificado como severo (VEF1<40%) en el 7.1%, moderado (VEF1 40-69%) en el 35.7%, leve (VEF1 70-79%) en el 7.1% y como normal (VEF1>80%) en el 50%. Se concluye que durante los 4 años de seguimiento en el programa de FQ del HIUSJ, ocurre una mejoría del IMC en todo el grupo y un deterioro de la función pulmonar. Se resalta la importancia de constituir más centros de referencia para mejorar los desenlaces clínicos e implementar un registro Nacional para hacer seguimiento a través del tiempo.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Testes de Função Respiratória , Estado Nutricional , Prestação Integrada de Cuidados de Saúde , Fibrose Cística/fisiopatologia , Pseudomonas aeruginosa/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Índice de Massa Corporal , Evolução Clínica , Volume Expiratório Forçado , Epidemiologia Descritiva , Estudos de Coortes , Seguimentos , Fibrose Cística/microbiologia , Hospitalização/estatística & dados numéricos
5.
Appl Radiat Isot ; 141: 266-269, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30049552

RESUMO

In Mexico, previous studies performed to evaluate the image quality in 2D digital mammography facilities show a poor image quality that is not compatible with mammography screening that may modify breast cancer mortality rate. Image quality is lost due to the quality assurance programs are not implemented. We carried out an exploratory survey of thirty-six new (FFDM) units from a single manufacturer installed in several cities of the Mexican Republic with two types of target/filter combination (Mo/Mo and W/Rh). Tests were performed according to NOM-041-SSA1-2011 (Mexico), the regulation indicates that all facilities using digital mammography systems must maintain a QC program equal to the QC program recommended by the manufacturer. However, QC program recommended by the manufacturer meets with FDA and ACR Regulations. Digital mammography units evaluated exceeds quality image standards established by the ACR and FDA, even though, the W/Rh combination achieved a higher performance and reduces the average glandular dose. All mammography units met the quality control standards established by ACR, FDA and Mexican regulations. Then, the objective of this study was to evaluate the initial image quality and compliances with the manufacturer's quality control specifications before use it in patients in new full-field 2D digital mammography (FFDM) units and compares average glandular dose (AGD) with FFDM units using different anode/filter combinations (Mo/Mo and W/Rh).


Assuntos
Mamografia/normas , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia/instrumentação , Mamografia/estatística & dados numéricos , México , Imagens de Fantasmas , Controle de Qualidade , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Razão Sinal-Ruído , Inquéritos e Questionários
6.
Rev Med Chil ; 146(4): 470-478, 2018 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-29999122

RESUMO

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is a frequent sleep-related breathing disorder being associated with cardiovascular, metabolic and neurobehavioral consequences. Most patients with OSAS are untreated because they are not timely diagnosed. AIM: to determine the association of sleep symptoms and body mass index in patients with OSAS diagnosed by polysomnography. MATERIAL AND METHODS: We studied 144 patients aged 47 ± 14 years (75% males) in whom a polysomnography was done. These patients answered a sleep symptom questionnaire and the Epworth sleepiness scale. Their weight and body mass index was also recorded. RESULTS: Snoring and the presence of pauses during breathing were the symptoms with the higher sensitivity to predict the presence of OSAS. Body mass index was significantly higher among patients with OSAS. No differences in the Epworth scale were observed between patients with and without OSAS. CONCLUSIONS: Snoring and apneas while sleeping are symptoms that should lead to the suspicion of the presence of OSAS.


Assuntos
Apneia Obstrutiva do Sono/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Ronco , Inquéritos e Questionários , Adulto Jovem
7.
Rev. méd. Chile ; 146(4): 470-478, abr. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961417

RESUMO

Background: Obstructive sleep apnea syndrome (OSAS) is a frequent sleep-related breathing disorder being associated with cardiovascular, metabolic and neurobehavioral consequences. Most patients with OSAS are untreated because they are not timely diagnosed. Aim: to determine the association of sleep symptoms and body mass index in patients with OSAS diagnosed by polysomnography. Material and Methods: We studied 144 patients aged 47 ± 14 years (75% males) in whom a polysomnography was done. These patients answered a sleep symptom questionnaire and the Epworth sleepiness scale. Their weight and body mass index was also recorded. Results: Snoring and the presence of pauses during breathing were the symptoms with the higher sensitivity to predict the presence of OSAS. Body mass index was significantly higher among patients with OSAS. No differences in the Epworth scale were observed between patients with and without OSAS. Conclusions: Snoring and apneas while sleeping are symptoms that should lead to the suspicion of the presence of OSAS.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Apneia Obstrutiva do Sono/diagnóstico , Ronco , Índice de Gravidade de Doença , Índice de Massa Corporal , Inquéritos e Questionários , Análise de Variância , Sensibilidade e Especificidade , Polissonografia
8.
Br J Dermatol ; 176(2): 423-430, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28004387

RESUMO

BACKGROUND: Previous studies have shown that skin disease in dermatomyositis (DM) is best assessed using the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI). Although the CDASI has been validated for use by dermatologists, it has not been validated for use by other physicians such as rheumatologists and neurologists, who also manage patients with DM and assess skin activity in clinical trials. OBJECTIVES: To assess the reliability of the CDASI among dermatologists, rheumatologists and neurologists. METHODS: Fifteen patients with cutaneous DM were assessed using the CDASI and the Physician Global Assessment (PGA) by five dermatologists, five rheumatologists and five neurologists. RESULTS: The mean CDASI activity scores for dermatologists, rheumatologists and neurologists were 21·0, 21·8 and 20·8, respectively. These mean scores were not different among the specialists. The CDASI damage score means for dermatologists, rheumatologists and neurologists were 5·3, 7·0 and 4·8, respectively. The mean scores between dermatologists and rheumatologists were significantly different, but the means between dermatologists and neurologists were not. The intraclass correlation coefficients (ICCs) for interrater reliability for CDASI activity and damage were good to excellent for dermatologists and rheumatologists, and moderate to excellent for neurologists. The ICCs for intrarater reliability for CDASI activity and damage were excellent for dermatologists and rheumatologists and moderate to excellent for neurologists. The PGA displayed lower interrater and intrarater reliability relative to the CDASI. CONCLUSIONS: Our results confirm the reliability of the CDASI when used by dermatologists and rheumatologists. The data for its use by neurologists were not as robust.


Assuntos
Dermatologistas , Dermatomiosite/diagnóstico , Neurologistas , Reumatologistas , Índice de Gravidade de Doença , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
9.
Artigo em Inglês | MEDLINE | ID: mdl-24594886

RESUMO

This paper reports on both cathodoluminescence (CL) and blue thermoluminescence (TL) emission of well-characterized natural Spanish and Brazilian apatites [Ca5(PO4)3(OH, F, Cl)]. Chemical analyses performed by means of Electron Microprobe Analysis (EMPA) have shown the presence of trace elements that can induce CL bands. In this sense, the apatites shown emission bands peaked at 3.26, 2.86, 2.62, 2.14, 2.02 and 1.94eV are respectively linked to substitutional Ce(3+), Tb(3+), Dy(3+), Pr(3+), Sm(3+) and Mn(2+) in structural Ca(2+) positions. The 3.18eV emission band can be associated with intrinsic electron defects on oxygen of the phosphate group (PO4)(3-). The presence of (UO2)(2+) gives rise to an emission at 2.14eV. All the studied aliquots exhibit one single UV-blue TL peak that modifies the position from one sample to another (370, 256 and 268°C) probably due to (i) the variation in the crystallinity index (from 0.88 to 1.34) and (ii) successive chemical processes such as oxidation, dehydration, dehydroxylation, and fluorine ions losses due to the thermal readout.


Assuntos
Apatitas/química , Cálcio/análise , Elementos da Série dos Lantanídeos/análise , Luminescência , Medições Luminescentes , Manganês/análise , Análise Espectral Raman , Urânio/análise , Difração de Raios X
10.
Pediatr. aten. prim ; 16(61): e19-e32, ene.-mar. 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-121751

RESUMO

Los problemas de salud mental en niños y adolescentes son motivos de consulta frecuentes en Atención Primaria (AP). En la mayor parte de los casos, un tratamiento ambulatorio desde AP o desde su Centro de Salud Mental (CSM) es suficiente para una mejora significativa. Sin embargo, en ocasiones la sintomatología puede ser la manifestación de una estructuración psíquica seriamente dañada. En esos casos, donde existe un trastorno mental grave (TMG), es posible que dichos tratamientos ambulatorios no sean suficientes. En el presente artículo se presenta el Hospital de Día-Centro Educativo Terapéutico (HD-CET) Pradera de San Isidro. Un dispositivo de hospitalización parcial que forma parte de la red de Salud Mental de la Comunidad de Madrid, en el que se atiende a menores con TMG mediante un tratamiento ambulatorio intensivo. EL HD-CET consta de dos unidades: la de infantil (de 6 a 11 años) y la de adolescentes (de 12 a 17 años). Ambas cuentan con un equipo multidisciplinar de profesionales de Salud Mental, así como con un equipo docente encargado del aspecto académico de los pacientes. Se trabaja desde el modelo de comunidad terapéutica, procurando proporcionar al paciente experiencias emocionales correctoras que logren una mejora significativa y profunda del TMG (AU)


Child and adolescence mental health conditions are common in Primary Care (PC). In most cases, Mental Health Services (MHS) will achieve a good response in an outpatient basis. However, certain symptoms may indicate seriously damaged psychic structures, as found in Severe Mental Disorders (SMD), whose ambulatory care in PC and MHS may not be sufficient. Pradera de San Isidro Mental Health Day Care Hospital-Educational Therapeutic Centre (DCH-ETC) is part of Madrid Regional Mental Health Care Services, attending children and adolescents with SMD in a outpatient intensive program. DCH-ETC comprises a Children Unit attending patients of 6 to 11 years and an Adolescents Unit for patients from 12 to 17 years. A team of teachers is responsible for the continuing academic education of patients. With a Therapeutic Community model, the program aims to provide corrective emotional experiences leading to a deep and significant improvement in SMD (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Hospital Dia , Transtornos Mentais/epidemiologia , Psicofarmacologia/métodos , Psicofarmacologia/tendências , Terapia de Relaxamento/métodos , Terapia de Relaxamento/organização & administração , Terapia de Relaxamento/tendências , Diagnóstico Precoce , Saúde Mental/estatística & dados numéricos , Saúde Mental/normas , Serviços de Saúde Comunitária , Psiquiatria Comunitária/organização & administração , Psicofarmacologia/organização & administração , Psicofarmacologia/normas , Isolamento Social/psicologia , Confusão/terapia
11.
Appl Radiat Isot ; 83 Pt C: 230-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24268397

RESUMO

Calculations of fluence and absorbed dose in head tissues due to different photon energies were carried out using the MCNPX code, to simulate two models of a patient's head: one spherical and another more realistic ellipsoidal. Both head models had concentric shells to describe the scalp skin, the cranium and the brain. The tumor was located at the center of the head and it was a 1 cm-radius sphere. The MCNPX code was run for different energies. Results showed that the fluence decreases as the photons pass through the different head tissues. It can be observed that, although the fluence into the tumor is different for both head models, absorbed dose is the same.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Modelos Biológicos , Fótons , Dosagem Radioterapêutica , Humanos
12.
J Frailty Aging ; 3(3): 173-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27050064

RESUMO

BACKGROUND: Older adults in Mexico are a growing share of the population and are a largely vulnerable group with increased risk of food insecurity and potential detrimental health effects stemming from it. OBJECTIVES: This study assesses the face validity of the Latin American and Caribbean Food Security Scale (ELCSA) among Mexican urban older adults of low socioeconomic status. DESIGN: Qualitative study based on 4 focus groups. SETTING: The focus groups were conducted in community organizations for the elderly in an area of Mexico City with a high proportion of poverty. PARTICIPANTS: The focus groups included a total of 36 older adults aged 65 and over who consented to participate. MEASUREMENTS: Two initial focus groups were conducted to assess how older adults understood the food security construct and each of the ELCSA items. Based on these findings, ELCSA was modified and retested for face validity through two additional focus groups. RESULTS: The initial focus groups suggested that several of the scale items were not well understood, leading to editorial modifications of the scale. The final focus groups indicated that the modified version of the scale improved substantially ELCSA's face validity in this sample. CONCLUSIONS: The modified ELCSA led to a greater understanding of most scale items. Further qualitative research is needed to improve food insecurity measurements among older adults in Latin America.

13.
Appl Radiat Isot ; 83 Pt C: 252-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23746708

RESUMO

The neutron spectra have been measured in two beam ports, one radial and another tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research in Mexico. Measurements were carried out with the reactor core loaded with high enriched uranium fuel. Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a (6)LiI(Eu) scintillator and 2, 3, 5, 8, 10 and 12 in.-diameter high-density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code. For each spectrum total flux, mean energy and ambient dose equivalent were determined. Measured spectra show fission, epithermal and thermal neutrons, being harder in the radial beam port.

14.
Artigo em Inglês | MEDLINE | ID: mdl-24210921

RESUMO

The luminescence (cathodoluminescence and thermoluminescence) properties of natural bones (Siberian mammoth and adult elephant), commercial hydroxyapatite and collagen were analyzed. Chemical analyses of the natural bones were determined using by Electron Probe Micro-Analysis (EMPA). Structural, molecular and thermal characteristics were determined by X-ray Diffraction (XRD), Raman spectroscopy and Differential Thermal and Thermogravimetric analysis (DTA-TG). Cathodoluminescence (CL) spectra of natural bones and collagen showed similar intense broad bands at 440 and 490 nm related to luminescence of the tetrahedral anion [Formula: see text] or structural defects. A weaker luminescence exhibited at 310 nm could be attributed to small amount of rare earth elements (REEs). Four luminescent bands at 378, 424, 468 and 576 nm were observed in the commercial hydroxyapatite (HAP). Both natural bones and collagen samples exhibited natural thermoluminescence (NTL) with well-defined glow curves whereas that the induced thermoluminescence (ITL) only appears in the samples of commercial hydroxyapatite and collagen. Additional explanations for the TL anomalous fading of apatite, as a crucial difficulty performing dosimetry and dating, are also considered.


Assuntos
Osso e Ossos/química , Colágeno/química , Durapatita/química , Animais , Bovinos , Elefantes , Luminescência , Medições Luminescentes , Mamutes , Análise Espectral Raman , Difração de Raios X
15.
Appl Radiat Isot ; 83 Pt C: 192-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23707740

RESUMO

This paper presents the experimental results of the thermoluminescent (TL) characteristics of synthetic hydroxyapatite (SHAp) obtained by the sol-gel method. For preparation of the SHAp powders, phosphorus pentoxide (P2O5) and calcium nitrate tetrahydrated (Ca(NO3)2-4H2O) were used. The powders obtained were submitted at different temperatures. The structural and morphological characterization were carried out using X-ray diffraction (XRD) and scanning electron microscopy techniques. TL glow curve exhibited two peaks centered at around 200 °C and 300 °C. TL response of SHAp as a function of gamma absorbed dose was linear over a wide dose range. Fading of the storage information in the samples irradiated was also studied. The experimental results show that the synthetic hydroxyapatite obtained by the sol-gel method may have used in gamma radiation dosimetry applications.

16.
Appl Radiat Isot ; 83 Pt C: 245-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23938078

RESUMO

The purpose of this study was to assess the current status of image quality and dose in computed radiographic digital mammography (CRDM) systems. Studies included CRDM systems of various models and manufacturers which dose and image quality comparisons were performed. Due to the recent rise in the use of digital radiographic systems in Mexico, CRDM systems are rapidly replacing conventional film-screen systems without any regard to quality control or image quality standards. Study was conducted in 65 mammography facilities which use CRDM systems in the Mexico City and surrounding States. The systems were tested as used clinically. This means that the dose and beam qualities were selected using the automatic beam selection and photo-timed features. All systems surveyed generate laser film hardcopies for the radiologist to read on a scope or mammographic high luminance light box. It was found that 51 of CRDM systems presented a variety of image artefacts and non-uniformities arising from inadequate acquisition and processing, as well as from the laser printer itself. Undisciplined alteration of image processing settings by the technologist was found to be a serious prevalent problem in 42 facilities. Only four of them showed an image QC program which is periodically monitored by a medical physicist. The Average Glandular Dose (AGD) in the surveyed systems was estimated to have a mean value of 2.4 mGy. To improve image quality in mammography and make more efficient screening mammographic in early detection of breast cancer is required new legislation.


Assuntos
Mamografia/normas , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Feminino , Humanos , Programas de Rastreamento , México/epidemiologia
17.
Acta Ortop Mex ; 27(4): 256-9, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24707616

RESUMO

INTRODUCTION: Accidents currently rank first among causes of complex lower limb injuries. The most common open long bone fractures are tibial fractures. Estimates indicate that there are 492,000 new fractures every year, with a prevalence of 100,000 cases that do not heal. CLINICAL CASE: Young, female patient who underwent emergency surgery for a Gustilo III A open comminuted fracture of the left proximal tibia. Surgical toilette was performed several times until the soft tissues improved. Then internal fixation of large fragments was performed with a cortical screw and Professor Rodrigo Alvarez Cambras' external fixator was used to heal the fracture. The combined approach consisting of internal and external fixation is discussed within the setting of these difficult fractures.


Assuntos
Fixação de Fratura/métodos , Fraturas Expostas/cirurgia , Fraturas da Tíbia/cirurgia , Adulto , Fixadores Externos , Feminino , Fixação de Fratura/instrumentação , Fixação Interna de Fraturas , Humanos
18.
Acta Ortop Mex ; 27(6): 367-70, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24716366

RESUMO

OBJECTIVE: To assess the quality of life of patients with functional knee impairment at a primary health care unit. MATERIAL AND METHODS: Descriptive study of 317 primary health care patients with functional impairment due to gonarthrosis. The WOMAC and SF-36 questionnaires were used to assess functional impairment and quality of life, respectively. We used chi2 and Kendall's Tau-b to prove the hypothesis. RESULTS: 317 patients, 137 (43%) males, 180 (57%) females, mean age 72.46, standard deviation +/- 6.76 with a range of 65-95. Mild functional impairment occurred in 222 (70%) patients; 52.37% of patients had a fair quality of life. When the association between functional impairment and quality of life was studied, chi2 was 106.78, with p = 0.00, the application of Kendall's Tau-b to show a relation was -0.502 with a significant p = 0.00, thus showing the relation between both variables. Both variables were dichotomized and the degree of dependence of quality of life from functional impairment was assessed; 120 (37.85%) patients had poor quality of life and mild functional impairment with chi2 = 75.50, p = 0.00, Kendall's Tau-b = -0.428, p = 0.00. CONCLUSION: The quality of life of patients with gonarthrosis ranges from fair to poor and is directly dependent on the degree of functional impairment.


Assuntos
Artropatias , Articulação do Joelho , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Artropatias/fisiopatologia , Masculino , Atenção Primária à Saúde , Estudos Prospectivos
19.
Appl Radiat Isot ; 71 Suppl: 30-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22633888

RESUMO

Thermoluminescence dosimetry (TLD) is applied worldwide for personal and medical dosimetry. TLD method has resulted in many interesting findings in medicine as TL dosimeters have many relevant advantages such as high sensitivity, small physical size, tissue equivalence, etc. The main characteristics of various TL materials used in radiation measurements and their practical consequences are overviewed: well defined TL glow curve, batch homogeneity, signal stability after irradiation, precision and accuracy, response with dose, and influence of energy. In this paper a brief summary of the advances in the application of thermally stimulated luminescence (TSL) to dosimetry in radiation therapy application is presented.


Assuntos
Dosimetria Termoluminescente/métodos , Humanos , Radiometria/métodos , Reprodutibilidade dos Testes
20.
Appl Radiat Isot ; 71 Suppl: 57-60, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22608982

RESUMO

The purpose of this study was to evaluate the dose received by chest x-rays in neonatal care with thermoluminescent dosimetry and to determine the level of exposure where the quantum noise level does not affect the diagnostic image quality in order to reduce the dose to neonates. In pediatric radiology, especially the prematurely born children are highly sensitive to the radiation because of the highly mitotic state of their cells; in general, the sensitivity of a tissue to radiation is directly proportional to its rate of proliferation. The sample consisted of 208 neonatal chest x-rays of 12 neonates admitted and treated in a Neonatal Intensive Care Unit (NICU). All the neonates were preterm in the range of 28-34 weeks, with a mean of 30.8 weeks. Entrance Surface Doses (ESD) values for chest x-rays are higher than the DRL of 50 µGy proposed by the National Radiological Protection Board (NRPB). In order to reduce the dose to neonates, the optimum image quality was achieved by determining the level of ESD where level noise does not affect the diagnostic image quality. The optimum ESD was estimated for additional 20 chest x-rays increasing kVp and reducing mAs until quantum noise affects image quality.


Assuntos
Recém-Nascido Prematuro , Terapia Intensiva Neonatal , Doses de Radiação , Radiografia Torácica/métodos , Feminino , Humanos , Recém-Nascido , Masculino , Dosimetria Termoluminescente
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