Beta radiation excited thermoluminescence of SrB4O7 phosphors synthesized through solid state reaction.

In this work, the synthesis of SrB4O7 through solid state reaction and its beta particle excited thermoluminescence (TL) are reported. The glow curves show maxima around 200 and 300 -considered suitable for TL dosimetry-, and a remarkable reproducibility in successive irradiation - TL readout cycles. The integrated TL exhibits a linear dependence upon the irradiation dose in the tested dose range (from 1.0 up to 8.0 Gy). The lower detection limit and the sensitivity relative to the TLD-100 dosimeter are 88 mGy and 0.49, respectively. From the results here presented, we conclude that SrB4O7 synthesized through solid state reaction can be considered a phosphor material interesting to develop TL dosimeters.

Beta particle excited thermoluminescence of CaZrO3 phosphors synthesized by solid state reaction.

In this work, the synthesis through solid state reaction and the thermoluminescence (TL) characterization of pellet shaped CaZrO3 samples is reported. X-ray diffraction confirms that orthorhombic CaZrO3 was obtained. The glow curve has two maxima located at 149 and 216 °C as well as a less intense maximum around 350 °C when a 5.0 °C/s heating rate is used after 64 Gy of beta particle exposure. A remarkably reproducibility of the TL response is observed in repeated irradiation - TL readouts cycles. The TL as a function of the dose displays linear dependence in the dose range from 0.5 to 256 Gy. The intensity of the maximum located around 216 °C remains 61% 14 days after irradiation, and then remains closely constant for longer times. The synthesized CaZrO3 exhibits TL properties potentially of interest for use in radiation detection and dosimetry.

ANÁLISIS DEL ESTADO ACTUAL DE LA INGENIERÍA CLÍNICA EN LAS INSTITUCIONES HOSPITALARIAS DE CALI / ANALYSIS OF THE CURRENT STATE OF CLINICAL ENGINEERING IN HOSPITALS IN CALI / A ANÁLISE DO ESTADO ATUAL DA ENGENHARIA CLÍNICA EM HOSPITAIS DE CALI

En este trabajo se presentan los resultados obtenidos tras analizar la información recolectada en once instituciones prestadoras de servicios de salud (IPS) en la ciudad de Cali y municipios aledaños, sobre tres elementos clave para la buena práctica de la Ingeniería Clínica: adquisición de tecnología, gestión de mantenimiento y formación del personal. Se realizó una comparación entre las prácticas actuales de IC en las IPS encuestadas y las prácticas propuestas en la literatura existente. Se propone además una serie de aspectos a tomar en cuenta con miras a mejorar el desempeño de los departamentos de IC tanto en la ciudad como en el país.

This paper summarizes the results obtained after analyzing the information gathered in eleven institutions providing health services (IPS, in Colombia) in the city of Cali and surrounding municipalities, three key elements for good clinical engineering practice are presented: Acquisition technology, management, maintenance and staff training. A comparison between current practices in the surveyed IC at IPS and practices proposed in the literature was conducted. It also proposes a number of aspects to consider in order to improve performance of both IC departments in the city and in the country.

Este artigo apresenta os resultados obtidos depois de analisar as informações coletadas em onze instituições prestadoras de serviços de saúde (IPS), na cidade de Cali e municípios vizinhos, sobre três elementos-chave para a boa prática de engenharia clínica: aquisição de tecnologia, gestão de manutenção e treinamento de pessoal. Uma comparação foi feita entre as práticas atuais nas IPS e práticas propostos na literatura atual. Ele também propõe uma série de aspectos a considerar, a fim de melhorar o desempenho dos departamentos IC tanto na cidade quanto no país.

Hepatocellular carcinoma: ten years experience among veterans in Puerto Rico

PURPOSE: The aim of our study is to determine the characteristics of hepatocellular carcinoma (HCC) as well as risk factors, demographics, survival rates and the use of diagnostic and therapeutic modalities among veteran patients in Puerto Rico. METHODS: A retrospective study of 114 patients with Hispanic background and biopsy-proven HCC diagnosed at the VA Caribbean Healthcare System from 1992 to 2002 was performed. Demographics data, Child-Turcotte-Pugh (CTP) score, presence of cirrhosis, viral serology, alcohol and/or other liver diseases history, diagnostic modalities, lesion size, therapy, and overall survival were examined. RESULTS: The mean age was 66.6 years old. 82% had known underlying cirrhosis. 60% had alcoholic liver disease (ALD), 33% positive serology for hepatitis C (HCV) and 21% both. 5.3% had chronic hepatitis B virus (HBV) infection. Additional causes were not present. CTP classification was: A (42%), B (44%) and C (14%). Abdominal CT scan demonstrated most of the lesions, while ultrasound only 57%. Alfa-fetoprotein was diagnostic in 32%. Mean survival was 10.3 months, better for those with CTP score A. Only 42% of the patients received any kind of therapy. CONCLUSIONS: ALD is the principal underlying liver disease in our HCC patients, closely followed by chronic HCV infection. Less than half of our patients received treatment mainly due to advanced disease for which the over survival was less than a year. HCC continues to be a dreadful disease with poor prognosis for which aggressive screening should be considered for all patients with cirrhosis and advanced liver disease regardless of the cause.

Primary duodenal signet-ring cell carcinoma presenting as gastric outlet obstruction

Small bowel tumors occur rarely. We present an unusual case of a 68 year old man with gastric outlet obstruction secondary to a non-ampullary primary duodenal signet ring cell carcinoma. A review of the literature of small bowel malignant tumors is presented along with the case.

[Myocardial ischemia detection with adenosine administration and SPECT. Initial experience in Mexico]. / Detección de isquemia miocárdica mediante la administración de adenosina y técnica SPECT. Experiencia inicial en México.

UNLABELLED: Myocardial perfusion SPECT has a high sensitivity for the diagnosis of myocardial ischemia. Adenosine has been recently used to induce myocardial ischemia in the United States and Europe. At the present time there is not published experience using adenosine in Mexico. METHOD: We studied 22 patients with suspected myocardial ischemia. Coronary angiography was performed in 17 patients. We used a 8 mCi rest Tc-99m sestamibi followed by a 6 minute infusion of adenosine at a dose of 140 ug/kg/min; 24 mCi of Tc-99m were injected after the third minute of adenosine infusion. Patients returned 2 or 3 days later for a new stress study using physical stress or dipiridamole and the images were read using a 20 segments analysis and each segment was scored using a 5 points scale (0 = normal to 4 = absent uptake). The results were then compared with the adenosine images. RESULTS: The segmental score agreement between adenosine and physical or dipyridamole stress were good with 90% exact correlation. The side effects experienced by patients who received dipyridamole and adenosine were similar. CONCLUSION: Adenosine is a good alternative to induce myocardial ischemia. It showed a good correlation with physical or dipyridamole stress test.