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1.
Bull Environ Contam Toxicol ; 112(5): 65, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643315

RESUMEN

Transfer factors of some naturally-occurring and artificial radionuclides from an agricultural soil to rhizobacteria-treated Sesbania grandiflora, a small leguminous tree, were studied. Two plant growth promoting rhizobacteria (PGPR) strains (SCR17 and PCE2) were used to carry out an agricultural experiment in pots in semi-arid region (Syria). The results showed the bacterial strain (SCR17) increased the transfer and accumulation of 238U and 40K in Sesbania grandiflora, while both bacterial strains showed no effect on the accumulation of 234Th, 226Ra, 210Po and 210Pb in the treated plants. The transfer factor of 137Cs from soil to rhizobacteria-treated Sesbania grandiflora was negligible. The values of the transfer factors of 234Th, 226Ra, 210Po and 40K were found to be within the global values, while the values of the transfer factors of 238U and 210Pb were found to be relatively higher. This study highlights the importance of using Phytoremediation by PGPR strains for radionuclides-contaminated soils. Therefore, this method is a promising technique for the restoration and rehabilitation of contaminated sites with radionuclides, as it is low cost, easy to apply, and environmentally friendly.


Asunto(s)
Sesbania , Contaminantes del Suelo , Plomo , Suelo , Siria , Biodegradación Ambiental
2.
Arch Razi Inst ; 78(3): 963-972, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-38028841

RESUMEN

This study aimed to detect the levels of apurinic/apyrimidinic endonuclease 1 (APE1) gene expression and C-type lectin domain family 4 member M (CLEC4M) and their association with cisplatin chemotherapy in lung cancer patients. Overall, 105 individuals who attended the Al-Amal National Hospital for Cancer Management, Baghdad, Iraq, were enrolled in the study and divided into three equal groups. The groups included the patients newly diagnosed with lung cancer, cancer patients who received cisplatin, and the healthy control group. All study groups were subjected to the sampling of the venous blood for molecular analysis by real-time polymerase chain reaction (RT-PCR) to detect the APE1 gene and enzyme-linked immunosorbent assay (ELISA) for serological testing to measure the concentration of CLEC4M protein. Significantly, the values of both cancer groups were higher than those reported in the control group. The relative index revealed a significant difference in the mean fold change level of APE1 in the newly diagnosed group (3 fold) and cisplatin therapy patients group (2 fold), compared to the control group (P=0.005). No significant differences were detected between the two cancer groups in terms of fold change mean of expression, demographic characteristics, and cancer histological type. Regarding human CLEC4M protein level, cases receiving cisplatin (139.2±25.9) and newly diagnosed patients (331.0±38.1) had a highly significant difference with the control group (100.3±47.5, P<0.001). There was no significant difference between the concentration level of CLEC4M and all parameters in demographic characteristics and cancer histological type. This was the first study to demonstrate that higher expression levels of new APE1, CLEC4M, and glutathione, especially after chemotherapy, are beneficial as diagnostic and prognostic markers for resistance to platinum chemotherapy in Iraqi lung cancer patients.


Asunto(s)
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Cisplatino/efectos adversos , Endonucleasas/uso terapéutico , Ensayo de Inmunoadsorción Enzimática , Irak , ADN-(Sitio Apurínico o Apirimidínico) Liasa/genética , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Receptores de Superficie Celular/uso terapéutico , Moléculas de Adhesión Celular/uso terapéutico , Lectinas Tipo C/genética , Lectinas Tipo C/uso terapéutico
3.
Radiography (Lond) ; 29(6): 1115-1120, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37774578

RESUMEN

INTRODUCTION: Radiographers, like many health professionals, are in a high-risk group for succumbing to workplace demands beyond their ability to cope, particularly in the context of the COVID-19 pandemic resulting in occupational stress. Occupational stress has been linked to poor organisational commitment. Therefore, the purpose of this research was to evaluate radiographers' organisational commitment and occupational stress after the first wave of the COVID-19 pandemic. METHODS: A mixed method approach entailed data collected from purposively sampled Australian radiographers working during the first COVID-19 wave. The quantitative phase used an online commitment questionnaire, and 21 semi-structured individual virtual interviews were conducted in the qualitative phase. Data interpretation and analysis used statistical and thematic approaches. RESULTS: The quantitative data revealed a higher level of continuance than affective and normative commitment. Whereas the qualitative findings showed participants high levels of affective commitment to their occupation and, together with leadership support, working collectively towards a positive outcome. CONCLUSION: Despite the variety of occupational stressors that arose during the COVID-19 crisis, Australian radiographers enjoy a high level of occupational and organisational commitment. IMPLICATIONS FOR PRACTICE: Radiographers' organisational commitment represents their emotional and psychological attachment to their workplace, and radiographers experiencing occupational stress represent high levels of psychosomatic distress and burnout. Therefore, considering radiographers' organisational commitment and occupational stress is essential in the delivery of services, quality of patient care and radiographers well-being.


Asunto(s)
Agotamiento Profesional , COVID-19 , Estrés Laboral , Humanos , COVID-19/epidemiología , Pandemias , Australia/epidemiología , Agotamiento Profesional/psicología
4.
Appl Radiat Isot ; 194: 110692, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36724617

RESUMEN

Sorption of 226Ra from produced water with oil production on manganese oxide nanoparticles loaded on walnut shell media was investigated using batch-type technique. The results showed that 226Ra is effectively adsorbed onto the adsorbent with equilibrium time of approximately 30 min. Removal efficiency of 226Ra from produced water depends mainly on the adsorbent dose and concentration of associated ions; removal efficiency decreased when their concentrations increase. The maximum adsorption capacity is reached 58 Bq g-1. The adsorbent is effective and suitable for removing 226Ra ions from the produced water under the studied conditions in this work.

5.
J Environ Radioact ; 229-230: 106538, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33485191

RESUMEN

Transfer factors of radium 226(226Ra), lead 210(210Pb), polonium 210 (210Po), uranium 238 (238U) and thorium 234(234Th) from five different agricultural soils in Syria to coriander, parsley and mint were investigated in a pot culture experiment. Geometric means of transfer factors (TF)were226Ra (0.13),210Pb(0.03), 210Po (0.02) and 238U (1.76) were within worldwide values, while TF values for 234Th (1.35) were higher than those recorded globally. The available transfer factor (ATF) values ranged between 0.03 and 1.45, 0.33 and 3.2, 0.10 and 3.36, 1.30 and 16.2 and 1.0 and 6.95 for226Ra,210Pb,210Po, 238U and 234Th, respectively. However, it is worth mentioning that the data from pot experiments may not represent field conditions. Liquid/solid partition coefficients (Kd)of 226Ra, U, 210Pb and 210Po for55 soils representing the dominant types of soils in Syria were also determined. Geometric means of Kd values ranged from 280 to1200, 750 to1600, 350to 4800 and 100-120 L kg-1 for 226Ra, 238U, 210Pb and 210Po, respectively at pH = 4.0, and from 200 to 6700, 670 to 2400, 150 to 2100 and 100 to 160Lkg-1at pH = 5.5, and from 370 to 790, 130 to 550, 60 to 330 and370 to 920Lkg-1at pH = 7.0. The effects of soil mineral content, CEC, ECE, pH and soluble ions on the Kd values were investigated. In general, there were logarithmic relationships between the activity concentrations in soil and the Kd values (R2 ranged from 0.59 to 1.00 at pH 4.0). There were no relationships between the Kd values and soil pH.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Uranio , Radioisótopos/análisis , Suelo , Contaminantes Radiactivos del Suelo/análisis , Siria , Factor de Transferencia , Uranio/análisis
6.
Bull Environ Contam Toxicol ; 102(2): 239-245, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30474690

RESUMEN

Speciation of 238U, 210Po and 210Pb in six different types of Syrian soil (Entisols, Inceptisol, Aridisol, Mollisols, Vertisols and Rock outcrops) was studied using a four-step sequential extraction procedure. The binding nature of 238U, 210Po and 210Pb was correlated with soil properties including soil particles, pH, EC, OM, sand, silt and clay. The results showed that the exchangeable and carbonate fractions of 238U did not exceed 10%. In addition, the 238U, 210Po and 210Pb fractions bonded to organic matter increased as the soil clay content decreased. The highest 210Po fraction was found to be bonded to soil Fe/Al/Mn-oxides for Entisols soils (56%) and silica for Aridisol soils (53%). Soil clay content showed a linear correlation with 210Po concentrations in soils ranging from 0.34 to 0.91. The results are considered useful in assessing the risks resulting from soils contaminated by naturally occurring radioactive material from the phosphate and oil industry.


Asunto(s)
Radioisótopos de Plomo/análisis , Polonio/análisis , Contaminantes Radiactivos del Suelo/análisis , Suelo/química , Uranio/análisis , Radioisótopos de Plomo/clasificación , Polonio/clasificación , Contaminantes Radiactivos del Suelo/clasificación , Siria , Uranio/clasificación
8.
Biomed Res Int ; 2018: 5419313, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30069472

RESUMEN

Central-line-associated bloodstream infection (CLABSI) rates are a key quality metric for comparing hospital quality and safety. Manual surveillance systems for CLABSIs are time-consuming and often limited to intensive care units (ICUs). A computer-automated method of CLABSI detection can improve the validity of surveillance. A new web-based, multitiered surveillance system for predicting and reducing CLABSI is proposed. The system has the capability to collect patient-related data from hospital databases and hence predict the patient infection automatically based on knowledge discovery rules and CLABSI decision standard algorithms. In addition, the system has a built-in simulator for generating patients' data records, when needed, offering the capability to train nurses and medical staff for enhancing their qualifications. Applying the proposed system, both CLABSI rates and patient treatment costs can be reduced significantly. The system has many benefits, among which there is the following: it is a web-based system that can collect real patients' data from many IT resources using iPhone, iPad, laptops, Internet, scanners, and hospital databases. These facilities help to collect patients' actual data quickly and safely in electronic format and hence predict CLABSI efficiently. Automation of the patients' data diagnosis process helps in reducing CLABSI detection times. The system is multimedia-based; it uses text, colors, and graphics to enhance patient healthcare report generation and charts. It helps healthcare decision makers to review and approve policies and surveillance plans to reduce and prevent CLABSI.


Asunto(s)
Infecciones Relacionadas con Catéteres/epidemiología , Internet , Vigilancia de la Población , Cateterismo Venoso Central , Niño , Infección Hospitalaria , Bases de Datos Factuales , Femenino , Predicción , Hospitales , Humanos , Recién Nacido , Unidades de Cuidados Intensivos , Masculino
9.
Reprod Domest Anim ; 53(4): 872-879, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29602226

RESUMEN

The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non-breeding season in camel ovaries. A total of 21 mature, non-pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3-5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin-embedded ovarian tissues was performed to detect the localization of S-100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S-100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.


Asunto(s)
Camelus/fisiología , Inmunohistoquímica/veterinaria , Estaciones del Año , Células Tecales/fisiología , Animales , Femenino
10.
Biomed Res Int ; 2017: 3292849, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29085836

RESUMEN

Prediction of nosocomial infections among patients is an important part of clinical surveillance programs to enable the related personnel to take preventive actions in advance. Designing a clinical surveillance program with capability of predicting nosocomial infections is a challenging task due to several reasons, including high dimensionality of medical data, heterogenous data representation, and special knowledge required to extract patterns for prediction. In this paper, we present details of six data mining methods implemented using cross industry standard process for data mining to predict central line-associated blood stream infections. For our study, we selected datasets of healthcare-associated infections from US National Healthcare Safety Network and consumer survey data from Hospital Consumer Assessment of Healthcare Providers and Systems. Our experiments show that central line-associated blood stream infections (CLABSIs) can be successfully predicted using AdaBoost method with an accuracy up to 89.7%. This will help in implementing effective clinical surveillance programs for infection control, as well as improving the accuracy detection of CLABSIs. Also, this reduces patients' hospital stay cost and maintains patients' safety.


Asunto(s)
Infecciones Relacionadas con Catéteres/epidemiología , Minería de Datos/métodos , Bases de Datos Factuales , Infecciones Relacionadas con Catéteres/etiología , Infecciones Relacionadas con Catéteres/terapia , Humanos , Valor Predictivo de las Pruebas , Estados Unidos/epidemiología
11.
J Radiol Prot ; 37(3): 761-779, 2017 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-28581438

RESUMEN

The sensitivity of a novel silica-based fibre-form thermoluminescence dosimeter was tested off-site of a rare-earths processing plant, investigating the potential for obtaining baseline measurements of naturally occurring radioactive materials. The dosimeter, a Ge-doped collapsed photonic crystal fibre (PCFc) co-doped with B, was calibrated against commercially available thermoluminescent dosimetry (TLD) (TLD-200 and TLD-100) using a bremsstrahlung (tube-based) x-ray source. Eight sampling sites within 1 to 20 km of the perimeter of the rare-earth facility were identified, the TLDs (silica- as well as TLD-200 and TLD-100) in each case being buried within the soil at fixed depth, allowing measurements to be obtained, in this case for protracted periods of exposure of between two to eight months. The values of the dose were then compared against values projected on the basis of radioactivity measurements of the associated soils, obtained via high-purity germanium gamma-ray spectrometry. Accord was found in relative terms between the TL evaluations at each site and the associated spectroscopic results. Thus said, in absolute terms, the TL evaluated doses were typically less than those derived from gamma-ray spectroscopy, by ∼50% in the case of PCFc-Ge. Gamma spectrometry analysis typically provided an upper limit to the projected dose, and the Marinelli beaker contents were formed from sieving to provide a homogenous well-packed medium. However, with the radioactivity per unit mass typically greater for smaller particles, with preferential adsorption on the surface and the surface area per unit volume increasing with decrease in radius, this made for an elevated dose estimate. Prevailing concentrations of key naturally occurring radionuclides in soil, 226Ra, 232Th and 40K, were also determined, together with radiological dose evaluation. To date, the area under investigation, although including a rare-earth processing facility, gives no cause for concern from radiological impact. The current study reveals the suitability of the optical fibre based micro-dosimeter for all-weather monitoring of low-level environmental radioactivity.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Contaminantes Radiactivos del Suelo/análisis , Dosimetría Termoluminiscente/instrumentación , Calibración , Germanio/química , Fibras Ópticas , Dióxido de Silicio , Factores de Tiempo
12.
PLoS One ; 11(5): e0153913, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27149115

RESUMEN

Study has been made of the thermoluminescence (TL) response of silica-based Ge-doped cylindrical, flat and photonic crystal fibres (referred to herein as PCF-collapsed) to electron (6, 12 and 20 MeV) and photon (6, 10 MV) irradiation and 1.25 MeV γ-rays, for doses from 0.1 Gy to 100 Gy. The electron and photon irradiations were delivered through use of a Varian Model 2100C linear accelerator located at the University of Malaya Medical Centre and γ-rays delivered from a 60Co irradiator located at the Secondary Standard Dosimetry Laboratory (SSDL), Malaysian Nuclear Agency. Tailor-made to be of various dimensions and dopant concentrations (6-10% Ge), the fibres were observed to provide TL yield linear with radiation dose, reproducibility being within 1-5%, with insensitivity to energy and angular variation. The sensitivity dependency of both detectors with respect to field size follows the dependency of the output factors. For flat fibres exposed to 6 MV X-rays, the 6% Ge-doped fibre provided the greatest TL yield while PCF-collapsed showed a response 2.4 times greater than that of the 6% Ge-doped flat fibres. The response of cylindrical fibres increased with core size. The fibres offer uniform response, high spatial resolution and sensitivity, providing the basis of promising TL systems for radiotherapy applications.


Asunto(s)
Dióxido de Silicio/efectos de la radiación , Dosimetría Termoluminiscente , Relación Dosis-Respuesta en la Radiación , Electrones , Rayos gamma , Fibras Ópticas , Fotones , Radioterapia/métodos , Dióxido de Silicio/química
13.
PLoS One ; 10(6): e0128790, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26075909

RESUMEN

The environment of the Straits of Malacca receives pollution as a result of various industrial and anthropogenic sources, making systematic studies crucial in determining the prevailing water quality. Present study concerns concentrations of natural radionuclides and heavy metals in marine fish (Rastrelliger kanagurta) collected from the Straits of Malacca, since aquatic stock form an important source of the daily diet of the surrounding populace. Assessment was made of the concentrations of key indicator radionuclides (226Ra, 232Th, 40K) and heavy metals (As, Mn, Fe, Cr, Ni, Zn, Cu, Co, Sr, Al, Hg and Pb) together with various radiation indices linked to the consumption of seafish. The annual effective dose for all detected radionuclides for all study locations has been found to be within UNSCEAR acceptable limits as has the associated life-time cancer risk. The overall contamination of the sampled fish from heavy metals was also found to be within limits of tolerance.


Asunto(s)
Peces , Contaminación de Alimentos , Metales Pesados , Radiación , Animales , Monitoreo del Ambiente , Geografía , Humanos , Malasia , Metales Pesados/efectos adversos , Metales Pesados/análisis , Radioisótopos/química , Riesgo
14.
Radiat Prot Dosimetry ; 167(1-3): 196-200, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25956784

RESUMEN

Malaysia is among the countries with the highest fish consumption in the world and relies on seafood as a main source of animal protein. Thus, the radioactivity in the mostly consumed marine animals such as fishes, crustaceans and molluscs collected from the coastal waters around Peninsular Malaysia has been determined to monitor the level of human exposure by natural radiation via seafood consumption. The mean activity concentrations of naturally occurring radionuclides (226)Ra ((238)U), (228)Ra ((232)Th) and (40)K ranged from 0.67 ± 0.19 Bq kg(-1) (Perna viridis) to 1.20 ± 0.70 Bq kg(-1) (Rastrelliger), from 0.19 ± 0.17 Bq kg(-1) (Teuthida) to 0.82 ± 0.67 Bq kg(-1) (Caridea) and from 34 ± 13 Bq kg(-1) (Caridea) to 48 ± 24 Bq kg(-1) (Teuthida), respectively. The mean annual committed effective dose due to the individual radionuclides shows an order of (228)Ra > (226)Ra > (40)K in all marine samples. The obtained doses are less than the global internal dose of 290 µSv y(-1) set by the United Nations Scientific Committee on the Effects of Atomic Radiation, discarding any significant radiological risks to the populace of Peninsular Malaysia.


Asunto(s)
Radiación de Fondo , Peces/metabolismo , Exposición a la Radiación/análisis , Radioisótopos/farmacocinética , Agua de Mar/química , Contaminantes Químicos del Agua/farmacocinética , Animales , Carga Corporal (Radioterapia) , Sedimentos Geológicos/química , Malasia , Dosis de Radiación , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Contaminantes Químicos del Agua/análisis
15.
Radiat Prot Dosimetry ; 167(1-3): 165-70, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25935008

RESUMEN

Vegetable is an essential daily diet item for the people of Malaysia. This work addressed the radiation and heavy metal exposure scenarios through the consumption of vegetables. Kuala Selangor is located in Sungai Selangor estuary in the west coast of Peninsular Malaysia, which is susceptible to pollution load due to the presence of large-scale industrial and human activities. Radioactivity and heavy metals level in human diet is of particular concern for the assessment of possible radiological and chemical hazards to human health. Therefore, a comprehensive study was carried out to determine the radioactivity levels ((226)Ra, (228)Ra and (40)K) and heavy metal concentrations (Cr, As, Cd, Mn, Mg, Al, Sr, Rb, Sb, Ba, Hg, Fe, Ni, Zn, Cu, Bi and Pb) in 10 varieties of vegetable collected from different farmlands in Kuala Selangor region. The committed doses for (226)Ra, (228)Ra and (40)K due to consumption of vegetables were found 16.6±1.3, 23.6±1.7 and 58±5 µSv y(-1), respectively, with a total of 98±8 µSv y(-1). This dose imposes no significant threat to human health. The estimated cancer risk shows that probability of increase in cancer risk from daily intake of vegetables is only a minor fraction of International Commission on Radiological Protection values. The concentrations of heavy metal were below the daily intake recommended by the international organisations.


Asunto(s)
Dieta/estadística & datos numéricos , Metales Pesados/análisis , Neoplasias Inducidas por Radiación/epidemiología , Exposición a la Radiación/estadística & datos numéricos , Radioisótopos/análisis , Verduras/química , Análisis de los Alimentos/métodos , Humanos , Incidencia , Malasia/epidemiología , Monitoreo de Radiación/métodos , Monitoreo de Radiación/estadística & datos numéricos , Reproducibilidad de los Resultados , Medición de Riesgo , Sensibilidad y Especificidad
16.
BJOG ; 122(1): 27-37, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25145491

RESUMEN

BACKGROUND: In twin pregnancies, the rates of adverse perinatal outcome and subsequent long-term morbidity are substantial, and mainly result from preterm birth (PTB). OBJECTIVES: To assess the effectiveness of progestogen treatment in the prevention of neonatal morbidity or PTB in twin pregnancies using individual participant data meta-analysis (IPDMA). SEARCH STRATEGY: We searched international scientific databases, trial registration websites, and references of identified articles. SELECTION CRITERIA: Randomised clinical trials (RCTs) of 17-hydroxyprogesterone caproate (17Pc) or vaginally administered natural progesterone, compared with placebo or no treatment. DATA COLLECTION AND ANALYSIS: Investigators of identified RCTs were asked to share their IPD. The primary outcome was a composite of perinatal mortality and severe neonatal morbidity. Prespecified subgroup analyses were performed for chorionicity, cervical length, and prior spontaneous PTB. MAIN RESULTS: Thirteen trials included 3768 women and their 7536 babies. Neither 17Pc nor vaginal progesterone reduced the incidence of adverse perinatal outcome (17Pc relative risk, RR 1.1; 95% confidence interval, 95% CI 0.97-1.4, vaginal progesterone RR 0.97; 95% CI 0.77-1.2). In a subgroup of women with a cervical length of ≤25 mm, vaginal progesterone reduced adverse perinatal outcome when cervical length was measured at randomisation (15/56 versus 22/60; RR 0.57; 95% CI 0.47-0.70) or before 24 weeks of gestation (14/52 versus 21/56; RR 0.56; 95% CI 0.42-0.75). AUTHOR'S CONCLUSIONS: In unselected women with an uncomplicated twin gestation, treatment with progestogens (intramuscular 17Pc or vaginal natural progesterone) does not improve perinatal outcome. Vaginal progesterone may be effective in the reduction of adverse perinatal outcome in women with a cervical length of ≤25 mm; however, further research is warranted to confirm this finding.


Asunto(s)
Hidroxiprogesteronas/uso terapéutico , Enfermedades del Recién Nacido/prevención & control , Muerte Perinatal/prevención & control , Embarazo Gemelar , Nacimiento Prematuro/prevención & control , Progesterona/uso terapéutico , Progestinas/uso terapéutico , Caproato de 17 alfa-Hidroxiprogesterona , Administración Intravaginal , Adulto , Displasia Broncopulmonar/prevención & control , Hemorragia Cerebral/prevención & control , Medición de Longitud Cervical , Cuello del Útero/diagnóstico por imagen , Enterocolitis Necrotizante/prevención & control , Femenino , Humanos , Recién Nacido , Embarazo , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control , Resultado del Tratamiento
17.
Appl Radiat Isot ; 100: 79-83, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25468288

RESUMEN

Important thermoluminescence (TL) properties of five (5) different core sizes Ge-doped optical fibers have been studied to develop new TL material with better response. These are drawn from same preform applying different speed and tension during drawing phase to produce Ge-doped optical fibers with five (5) different core sizes. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge-doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (SEM) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in Secondary Standard Dosimetry Lab (SSDL) was used for irradiation covering dose range from 1Gy to 10Gy. The essential dosimetric parameters that have been studied are TL linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5cm length are annealed at temperature of 400°C for 1h period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1h at 400°C and subsequently 2h at 100°C to yield the highest sensitivity. TL responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100µm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20µm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Zeff) is found in the range (13.25-13.69) which is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. TL properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation dosimetry.

18.
J Environ Radioact ; 141: 51-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25531268

RESUMEN

Essential oils were extracted from 35 medicinal plants used by Syrians, organic compounds were determined in these oils and concentrations of (210)Po (210)Pb and (238)U were determined in the original plants and in the essential oils. The results showed that the highest activity concentrations of (210)Po and (210)Pb were found in leaves with large surfaces and in Sage were as high as 73.5 Bq kg(-1) and 73.2 Bq kg(-1), respectively. The activity concentration of (238)U was as high as 4.26 Bq kg(-1) in Aloe. On the other hand, activity concentrations of (210)Po ranged between 0.2 and 71.1 Bq kg(-1) in extracted essential oils for Rosemary and False yellowhead, respectively. The activity concentration of (210)Pb reached 63.7 Bq kg(-1) in Aloe oil. The activity concentrations of (238)U were very low in all extracted oils; the highest value was 0.31 Bq kg(-1) in peel of Orange oil. The transfer of (210)Po and (210)Pb from plant to its oil was the highest for Eugenia; 7.1% and 5.5% for (210)Po and (210)Pb, respectively. A linear relationship was found between the transfer factor of radionuclides from plant to its essential oil and the chemical content of this oil.


Asunto(s)
Radioisótopos de Plomo/metabolismo , Aceites Volátiles/química , Plantas Medicinales/química , Polonio/metabolismo , Uranio/metabolismo , Monitoreo de Radiación , Siria
19.
J Environ Radioact ; 135: 120-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24814722

RESUMEN

Soil-to-plant transfer factors (TFs) are of fundamental importance in assessing the environmental impact due to the presence of radioactivity in soil and agricultural crops. Tapioca and sweet potato, both root crops, are popular foodstuffs for a significant fraction of the Malaysian population, and result in intake of radionuclides. For the natural field conditions experienced in production of these foodstuffs, TFs and the annual effective dose were evaluated for the natural radionuclides (226)Ra, (232)Th, (40)K, and for the anthropogenic radionuclide (88)Y, the latter being a component of fallout. An experimental tapioca field was developed for study of the time dependence of plant uptake. For soil samples from all study locations other than the experimental field, it has been shown that these contain the artificial radionuclide (88)Y, although the uptake of (88)Y has only been observed in the roots of the plant Manihot esculenta (from which tapioca is derived) grown in mining soil. The estimated TFs for (226)Ra and (232)Th for tapioca and sweet potato are very much higher than that reported by the IAEA. For all study areas, the annual effective dose from ingestion of tapioca and sweet potato are estimated to be lower than the world average (290 µSv y(-1)).


Asunto(s)
Raíces de Plantas/metabolismo , Contaminantes Radiactivos del Suelo/metabolismo , Verduras/metabolismo , Malasia , Radioisótopos de Potasio/metabolismo , Radio (Elemento)/metabolismo , Torio/metabolismo
20.
J Environ Radioact ; 132: 8-14, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24508949

RESUMEN

The transfer of (137)Cs, (85)Sr, (131)I, (210)Po, (210)Pb and (238)U from feed to camel's milk was investigated in a pilot experiment with three lactating camels. For a period of 60 days, the animals were fed on spiked feed containing the studied radionuclides. They were subsequently returned to a contamination-free diet and monitored for another 90 days. The activity concentrations of (137)Cs, (85)Sr and (131)I in milk decreased with time and reached background levels after 20 days. Equilibrium transfer coefficients and biological half-lives were estimated and transfer coefficients were calculated as (8.1 ± 3.6) × 10(-4), (4.4 ± 1.6) × 10(-2), (7.8 ± 3.9) × 10(-4), (2.7 ± 3.5) × 10(-4), (1.8 ± 1.5) × 10(-4) and (7.0 ± 3.6) × 10(-3) d L(-1) for (85)Sr, (131)I, (137)Cs, (210)Po, (210)Pb and (238)U, respectively. The biological half-lives were estimated to be 6.4, 4.2, 8.9, and 53.3 days for (85)Sr, (131)I, (137)Cs, and (238)U, respectively. Estimates of the half-lives were based on a one component model: it was found that the half-life values measured for artificial radionuclides were slightly shorter than those for natural radionuclides. The data obtained in the study are the first published experimental data on radionuclide transfer to camel milk.


Asunto(s)
Alimentación Animal/análisis , Contaminación Radiactiva de Alimentos/análisis , Lactancia/efectos de la radiación , Leche/química , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Animales , Camelus , Radioisótopos de Cesio/análisis , Femenino , Radioisótopos de Plomo/análisis , Polonio/análisis , Radioisótopos de Estroncio/análisis , Factores de Tiempo
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