PVP solid dispersions containing Poloxamer 407 or TPGS for the improvement of ursolic acid release

Abstract Solid dispersions (SDs) of ursolic acid (UA) were developed using polyvinylpyrrolidone K30 (PVP K30) in combination with non-ionic surfactants, such as D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) or poloxamer 407 (P407) with the aim of enhancing solubility and in vitro release of the UA. SDs were investigated using a 24 full factorial design, subsequently the selected formulations were characterized for water solubility, X-ray diffractometry (XRD), differential scanning calorimetry (DSC), particle diameter, scanning electron microscopy, drug content, physical-chemical stability and in vitro release profile. SDs showed higher UA water-solubility than physical mixtures (PMs), which was attributed by transition of the drug from crystalline to amorphous or molecular state in the SDs, as indicated by XRD and DSC analyses. SD1 (with P407) and SD2 (with TPGS) were chosen for further investigation because they had higher drug load. SD1 proved to be more stable than SD2, revealing that P407 contributed to ensure the stability of the UA. Furthermore, SD1 and SD2 increased UA release by diffusion and swelling-controlled transport, following the Weibull model. Thus, solid dispersions obtained with PVP k-30 and P407 proved to be advantageous to enhance aqueous solubility and stability of UA.

Physicochemical characterization and cosmetic applications of Passiflora nitida Kunth leaf extract

Abstract Passiflora nitida Kunth, an Amazonian Passiflora species, is little studied, although the specie's high biological potential. Herein the plant's pharmacognostic characterization, extract production, antioxidant potential evaluation, and application of this extract in cosmetic products is reported. The physical chemical parameters analyzed were particle size by sieve analysis, loss through drying, extractive yield, total ash content, laser granulometry, specific surface area and pore diameter (SBET), differential scanning calorimetry, thermogravimetry (TG), and wave dispersive X-Ray fluorescence (WDXRF). Total phenol/flavonoid content, LC-MS/MS analysis, DPPH and ABTS antioxidant radical assays, cytotoxicity, melanin, and tyrosinase inhibition in melanocytes test provided evidence to determine the content of the major constituent. P. nitida dry extract provided a fine powder with mesopores determined by SBET, with the TG curve showing five stages of mass loss. The antioxidant potential ranged between 23.5-31.5 mg∙mL-1 and tyrosinase inhibition between 400-654 µg∙mL-1. The species presented an antimelanogenic effect and an inhibitory activity of cellular tyrosinase (26.6%) at 25 µg/mL. The LC-MS/MS analysis of the spray-dried extract displayed the main and minor phenolic compounds constituting this sample. The results indicate that P. nitida extract has promising features for the development of cosmetic formulations

Formulation, Optimization, in vitro and in-vivo evaluation of levofloxacin hemihydrate Floating Tablets

Abstract The objective of the present investigation was to design, optimize and characterize the gastro retentive floating levofloxacin tablets and perform in-vivo evaluation using radiographic imaging. The floating tablets were prepared by using polymers i.e hydroxy propyl methyl cellulose (HPMC-K4M) and carbopol-940 individually and in combination by nonaquous granulation method. All the Formulations were evaluated for swelling index (S.I), floating behavior and in-vitro drug release kinetics. The compatibility study of levofloxacin with other polymers was investigated by FTIR, DSC, TGA and XRD. Results from FTIR and DSC revealed no chemical interaction amongst the formulation components. The optimized formulation (F11) showed floating lag time (FLT), total floating time (TFT) swelling index (S.I) of 60 sec, >16h and approximately 75 %, respectively. Moreover, F11 showed zero order levofloxacin release in simulated gastric fluid over the period of 6 h. X-ray studies showed that total buoyancy time was able to delay the gastric emptying of levofloxacin floating tablets in rabbits for more than 4 hours. In conclusion the optimized formulation (F11) can be used for the sustained delivery of levofloxacin for the treatment of peptic ulcer.

Historia y evolución de la radiología en Centroamérica / History and evolution of radiology in Central America

En 1895, el físico alemán Wilhelm Conrad Röntgen descubrió una nueva forma de radiación que la llamó"radiación X" para denotar su naturaleza desconocida, un año después del descubrimiento; Guatemala yChile fueron los primeros países de América Latina que utilizaron la nueva tecnología. El propósito de esta revisión bibliográfica es ofrecer una síntesis delos principales hechos y fechas que dieron lugar a la historia de la radiología en Centroamérica, haciendo énfasis en la evolución histórica en Honduras, desde la aparición del primer aparato de rayos X hasta la adquisición de la última tecnología radiológica. Se presentan los primeros radiólogos del país formadosen prestigiosas universidades y centros hospitalarios extranjeros que contribuyeron a mejorar la calidaddiagnóstica y terapéutica de los centros asistenciales. Se realizó una revisión sistemática de la literatura existente en revistas científicas consultando las basesde datos; Medline, Lilacs, e Hinari y otros que incluían artículos relacionados con la historia de la radiología...(AU)

Hybrid treatment of bullet embolism at the abdominal aortic bifurcation, complicated with thoracoabdominal aorta pseudoaneurysm and common iliac artery occlusion: case report / Tratamento híbrido de embolia por projétil de arma de fogo em bifurcação aórtica abdominal complicada com pseudoaneurisma de aorta tóraco-abdominal e oclusão de artéria ilíaca comum: relato de caso

Embolization due to a firearm projectile entering the bloodstream is a rare event that is unlikely to be suspected during initial treatment of trauma patients. We describe and discuss a case of bullet embolism of the abdominal aortic bifurcation, complicated by a pseudoaneurysm of the thoracoabdominal aorta and occlusion of the right common iliac artery, but successfully treated using a combination of endovascular methods and conventional surgery.

A embolização por projétil de arma de fogo na circulação sanguínea é rara e de difícil suspeição no atendimento inicial ao trauma. Relatamos e discutimos um caso de embolia em bifurcação aórtica abdominal complicada com pesudoaneurisma de aorta tóraco-abdominal e oclusão de artéria ilíaca comum direita, tratada de forma efetiva pelos métodos endovascular e cirúrgico convencional.

Protection effect of sanguinarine on whole-body exposure of X radiation in BALB/c mice

To investigate the effects of sanguinarine (SAN) on acute radiation induced injury in mice, 45 mice were randomly divided into control, 10 Gy and SAN+10 Gy groups. Mice in the 10 Gy and SAN+10 Gy groups were exposed to single X-ray radiation with an accumulated dose of 10 Gy. Mice in the SAN+10 Gy group were administered intraperitoneally with 2.5 mg/kg body weight of SAN before radiation. Five days after radiation exposure, 5 mice from each group were sacrificed and samples of the small intestine, lung, spleen and liver were fixed for histopathological examinations. Compared with the 10 Gy group, radiation sickness was obviously delayed or attenuated in the SAN+10 Gy group. Survival analysis showed a significant difference between 2 radiation groups (P<0.05) and mean survival time was 3 days longer in the SAN+10 Gy group than in the 10 Gy group (7.21±0.19 vs. 4.20±0.13, P<0.001). Radiation-induced organ damage, based on histopathological examinations, was decreased by SAN pretreatment. Chiu’s pathology grading scores, which is an index of intestinal damage, was significantly lower in the SAN+10 Gy group than in the 10 Gy group (2.77±0.48 vs. 4.37±0.31, P<0.01). A similar result was obtained in the pathological score of lung (1.67±0.21 vs. 2.33±0.38, P<0.01). Our preliminary findings demonstrated that SAN protects animals against radiation-induced sickness and acute damage to organs and following animal death.

Para investigar os efeitos da sanguinarina (SAN) em lesões induzidas em ratos por radiação aguda, 45 ratos foram aleatoriamente divididos em grupo controle, grupo 10 Gy e grupo SAN+10 Gy. Os ratos dos grupos 10 Gy e SAN+10 Gy foram expostos à radiação de raio-X simples com uma dose acumulada de 10 Gy. Aos ratos do grupo SAN+10 Gy administraram-se, intraperitonealmente, 2.5 mg/kg de peso de SAN antes da radiação. Aos 5 dias de exposição à radiação, sacrificaram-se 5 ratos de cada grupo e retiraram-se amostras do intestino delgado, pulmões, baço e fígado para exames histopatológicos. Comparando com o grupo 10 Gy, a doença por radiação foi claramente atrasada e atenuada no grupo SAN+10 Gy. A análise de sobrevivência mostrou diferença significativa entre os dois grupos de radiação (P<0.05) e o tempo de sobrevivência média foi de mais 3 dias no grupo SAN+10 Gy do que no grupo 10 Gy (7.21±0.19 vs 4.20±0.13, P<0.001). Danos induzidos nos órgãos por radiação, baseados em exames histopatológicos, foram reduzidos pelo pré-tratamento com SAN. As pontuações de classificação da patologia Chiu, um índice para os danos intestinais, foi significativamente menor no grupo SAN+10 Gy do que no grupo 10 Gy (2.77±0.48 vs 4.37±0.31, P<0.01). Resultado semelhante foi obtido na pontuação patológica do pulmão (1.67±0.21 vs 2.33±0.38, P<0.01). As nossas descobertas preliminares mostram que SAN protege os animais contra doenças induzidas pela radiação e danos agudos nos órgãos seguidos de morte animal.

Protective effect of some amino acids synthesized derivatives and their chelates on Escherichia coli under X-ray irradiation.

The protective effects of novel synthesized derivatives of some amino acids — nicotinyl-L-tyrosinate and nicotinyl-L-tryptophanate schiff bases and their Cu(II) and Mn(II) chelates on growth, survival and membrane-associated ATPase activity of E. coli under X-ray irradiation were investigated. The specific growth rate and survival of E. coli were decreased at 10, 20 and 30 Gy doses. However, as 30 Gy was found to be the most effective irradiation dose, it was chosen for studying the radio-protective properties of different compounds. These compounds could increase the bacterial cell protection against X-ray irradiation in concentration-dependent manner. They had a role in stimulation of synthesis or regulation of activity of metal-dependent enzymes, required for reversing the X-ray irradiation damage. The study may prove useful for further estimation of the effectiveness of different compounds as radio-protectors on bacteria and other cells, especially mammalian cells under X-ray irradiation.

Synthesis and Crystal Structure of Two Nitro-Regioisomers of cis-4(4-Methoxyphenyl)-3-Methyl-2-Phenyl-1, 2, 3, 4-Tetrahydroquinoline / Síntesis y estudio de la estructura cristalina de dos nitro regioisómerosde la cis-4-(4-metoxifenil)-3-metil-2-fenil-1, 2, 3, 4-tetrahydroquinolina

Dos nitro-regioisómeros de la moléculacis-4-(4-metoxifenil)-3-metil-2-fenil-1,2,3,4-tetrahydroquinolina fueronpreparados vía una síntesis one-pot de tres componentes basada en lareacción de cicloadición imino Diels-Alder catalizada por BF3.OEt2. Sucompleta caracterización estructural se llevó a cabo usando la técnicade difracción de rayos-X de monocristal y métodos espectroscópicos.La pureza de los productos y la composición de las mezclas de reacciónfueron monitoreadas por cromatografía en capa fina (CCD). Losproductos fueron aislados y purificados usando cromatografía encolumna. Las sustancias fueron identificadas usando resonancia magnéticanuclear (RMN) y espectrometría de masas (EM). Los datos para lacaracterización por difracción de rayos-X fueron colectados usando undifractómetro Bruker AFC7S Mercury con radiación de Mo-Kα (λ =0.71073Å) a temperatura ambiente. Las estructuras de los regio-isómerosfueron confirmadas por 1H RMN y 13C RMN y la estructura cristalinafue estudiada usando la difracción de rayos-X de monocristal. El análisisespectroscópico (RMN, EM y difracción de rayos-X) mostró una completacaracterización y permitió establecer la correcta estereoquímica para elanillo tetrahidroquinolínico. El empaquetamiento molecular en el cristalpara el regioisómero 5-nitro 4 es producto de la combinación de enlaces dehidrógeno intermoleculares e interacciones de van der Waals, mientras queen el 7-nitro regioisómero 3 el empaquetamiento se debe principalmente ainteracciones intermoleculares débiles de tipo van der Waals y N—H••• π...

Here we synthesized two nitro regioisomersof cis-4-(4-methoxyphenyl)-3-methyl-2-phenyl-1,2,3,4-tetrahydroquinoline via the “one pot” three-componentimino Diels-Alder reaction catalyzed by BF3.OEt2and completed its structural characterization using thesingle crystal X-ray diffraction technique and otherspectroscopic methods. To monitor the purity of theproducts and the composition of the reaction mixtureswe used thin layer chromatography, and isolated andpurified the products by column chromatography. Thenusing nuclear magnetic resonance (NMR) and massspectrometry (MS) identified the substances. We collectedX-ray diffraction data for crystal characterization byusing a Bruker AFC7S Mercury diffractometer with Mo-Kα radiation (λ = 0.71073Å) at room temperature. Thestructures of these regioisomers were confirmed by 1HNMR and 13C NMR studies and studied their crystalstructure using single crystal X-ray diffraction technique.The spectroscopy analyses (NMR, GC-MS and X-raydiffraction) provided a complete characterizationand enabled the correct stereochemistry for thetetrahydroquinoline ring. We determined the molecularpacking for the 5-nitro regioisomer 4 is the product ofthe combination of intermolecular hydrogen bonds andvan der Waals interactions, while for 7-nitro regioisomer3 is mainly due to weak intermolecular van der Waalsinteractions and N—H··· π...

Dois nitro regioisómeros da molécula cis-4-(4-metoxifenil)-3-metil-2-fenil-1,2,3,4-tetrahydroquinolina foram preparados através de umasíntese de um só recipiente de três componentes com base na reacçãode imino Diels-Alder cicloadição catalisada BF3.OEt2 e sua completacaracterização estrutural foi realizada usando a técnica de difracçãocristalografia de raios X, e outros métodos espectroscópicos. A purezado produto e a composição das misturas reaccionais foram monitorizadaspor cromatografia em camada fina (CCD). Os produtos foram isoladose purificados utilizando cromatografia em coluna. As substâncias foramidentificadaos por ressonância magnética nuclear (RMN) e espectrometriade massa (EM). Os dados para caracterização por difração de raios Xforam coletados usando um Bruker AFC7S Mercury difratômetro comMo-Ka radiação (λ = 0,71073Å) à temperatura ambiente. As estruturasdosa regioisómeros foram confirmadaos por 1H RMN e 13C RMN aestrutura de cristal foi investigada usando difracção de raios X de cristalúnico. As análises espectroscópicas (RMN, EM e difracção de raios-X)demonstraram uma completa caracterização e permitiramu estabelecer aestereoquímica correcta de anel tetrahidroquinolínico. O empacotamentomolecular no cristal para 5-nitro regioisómero 4 é derivado de umacombinação de ligações de hidrogénio intermoleculares e interacções devan der Waals, e ao 7-nitro regioisómero 3 embalagens é principalmentedevido a interacções intermoleculares fracas do tipo van der Waals e N-H• • • π...

morphological study of the effects of X-rays on the melanocytes of the skin, under light microscope

To observe the effects of x-irradiation on the melanocytes of the skin under light microscope. A prospective experimental study. The study was carried out at Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre Karachi from 2008 to 2009. Thirty animals were taken and were divided in to two groups. Each group was further subdivided into three subgroups containing five animals each according to the time of sacrifice i.e. 48 hours, 15[th] day and 45[th] day respectively. A single whole body x-irradiation in a dose of 5 Gy was given. Animals were sacrificed under ether anesthesia after completion of their respective periods. Tissues were processed and 4-5 micron thick paraffin embedded sections were cut and stained with Masson's Fontana stain. Insignificant [P>0.05] decrease in number of melanocytes was obtained when compared to control in group B1 animals. In group B2, increase in size and number of melanocytes was noted with long dendritic processes and large amount of melanin seen scattered between the layers of epidermis was present and results were moderately significant [P<0.01] in case of face and abdomen and significant [P<0.05] in case of back. In group B3 Size and number of melanocytes were also increased with large amount of melanin scattered between the layers of epidermis. The results obtained were highly significant [P<0.001] in case of face and moderately significant [P<0.01] in case of abdomen and back. X-irradiated skin of face, abdomen and back of the guinea pig depicted increased number and size of melanocytes with long dendritic processes and large amount of melanin scattered between the layers of epidermis

role of vitamin 'C' on the thickness of the epidermis after x-irradiation of the guinea pigs a morphological study under light microscope

To study the role of vitamin 'C' on X-irradiated epidermis of Guinea pigs under light microscope. A prospective experimental study. This study was conducted at the Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre Karachi 2008 to 2009. Twenty seven animals were taken and were divided in to three groups. Each group was further subdivided into three subgroups containing three animals each according to the time of sacrifice i.e. 48 hours, 15[th] day and 45[th] day respectively. A single whole body x-irradiation in a dose of 5 Gy was given. Group C animals were also given injection of vitamin-C intraperitoneally in the dose of 1mg/G/day. Animals were sacrificed under ether anaesthesia after completion of their respective periods. Tissues were processed and 4-5 micron thick paraffin embedded sections were cut and stained with Hematoxylin and eosin. Decrease in epidermal thickness was observed in Group B1 animals. Which is highly significant [P <0.001] when compared to control. Results of animals of Group B2, and B3 were non significant [P>0.05] when compared to control. Non significant results were obtained when Group C was compared to control group. X-irradiation damages the epidermis and vitamin 'C' minimizes the damaging effects

Grossesse et risques d'irradiations en radiodiagnostic : etat des connaissances des usagers au CHU de Yopougon

Objectifs : Evaluer l'etat des connaissances des usagers et des professionnels de la sante sur les risques d'irradiation de la femme enceinte au cours des explorations radiologiques et l'observation de l'application des regles de radioprotection relative a la femme enceinte par les utilisateurs de rayons X. Materiel et methodes : Notre etude prospective; realisee au CHU de Yopougon; a dure 6 mois. Nous avions interroge 60 femmes en grossesse ou susceptibles de l'etre; 30 medecins prescripteurs non radiologues; 29 techniciens d'imagerie medicale et 21 aides soignants sur les risques d'irradiation et les mesures de protection de la femme enceinte avant et pendant la realisation d'un examen radiologique utilisant les rayons X. Resultats : 73;68des medecins prescripteurs n'avaient pas de culture en radioprotection chez une femme enceinte ou en age de procreer. 93;10des patientes enceintes ou en age de procreer ignoraient l'existence des rayons X en radiodiagnostic et leur nocivite pour une femme enceinte ou susceptible d'etre enceinte. 80des manipulateurs de radiologie respectaient pas les regles elementaires de radioprotection. Conclusion : La sensibilisation des usagers des rayons X sur les risques d'irradiations chez une femme enceinte ou susceptible de l'etre est necessaire au CHU de Yopougon

Riscos ocupacionais em centros de radiodiagnóstico / Occupational hazards in radio diagnosis centers / Riesgos ocupacionales en centros de radiodiagnóstico

A adoção da cultura de proteção radiológica e de garantia de qualidade deve ser prioridade para a segurança dos exames radiológicos e do ambiente em que estão instalados os equipamentos de raios X. O artigo objetivou avaliar os procedimentos de biossegurança em três centros hospitalares de radiodiagnóstico. Realizou-se estudo prospectivo do tipo qualitativo observacional transversal, baseado no modelo de gestão organizacional desses centros, em Recife, de setembro/2008 a junho/2009, em cumprimento à Norma Regulamentadora 32 do Ministério do Trabalho. Observou-se que não conformidades técnicas ou operacionais ocorreram em função do desconhecimento da legislação; da ausência de programas de qualidade e segurança do paciente; da falta de sistematização de rotinas preventivas para manutenção dos equipamentos e falta de treinamento. Há necessidade da implantação de modelos de gestão focados no manuseio dos equipamentos segundo legislação e normas de biossegurança para prevenção de riscos à saúde ocupacional em centros de radiodiagnóstico.

Radiological protection and quality assurance should be a generalized priority integrating security standards of radiological tests and environmental protection where X-ray equipment is operational. This article aims at evaluating biosafety procedures. It includes a prospective study of qualitative cross-sectional observational approach, based on the organizational management model of three radio diagnostic centers in Recife, Pernambuco, Brazil. It ran from September 2008 to June 2009, and complied with the Regulatory Standard 32 of the Brazilian Labor Ministry. Technical and operational non-compliance was observed and found to result from the following factors: ignorance of legislation; lack of quality programs and of patient safety; lack of systematic preventive routines for the maintenance of equipment; and lack of training. There is need to implement business models focused on the handling of equipment in compliance with bio-security standards for the prevention of occupational hazards at diagnostic-radiology centers.

La adopción de la cultura de protección radiológica y de garantía de calidad debe ser prioridad para la seguridad de los exámenes radiológicos y del ambiente en que están instalados los equipos de rayos X. El artículo objetivó evaluar los procedimientos de bioseguridad en tres centros hospitalarios de radiodiagnóstico. Se realizó estudio prospectivo del tipo cualitativo observacional transversal, basado en el modelo de gestión organizacional de eses centros en Recife-PE-Brasil, de septiembre/2008 a junio/2009, en cumplimiento a la Norma Regulamentadora 32 del Ministerio del Trabajo. Se observó que no conformidades técnicas u operacionales acaecieron en función del desconocimiento de la legislación; de la ausencia de programas de calidad y seguridad del paciente; de la falta de sistematización de rutinas preventivas para manutención de los equipamientos y falta de entrenamiento. Hay necesidad de la implantación de modelos de gestión focados en el manoseo de los equipamientos según legislación y normas de bioseguridad para prevención de riesgos a ala salud laboral en centros de radiodiagnóstico.

Exposição à radiação ionizante na sala de hemodinâmica / Exposure to ionizing radiation in the cardiac catheterization lab

INTRODUÇÃO: Com a evolução tecnológica e o crescimento da cardiologia intervencionista, os níveis de exposição aos raios X dos pacientes e da equipe técnica assim como o número de procedimentos de cateterismo têm aumentado consideravelmente. Isso tem impacto no inerente risco de exposição à radiação ionizante, ainda subestimado por muitos. Os níveis dessa exposição necessitam de mensuração e correção periódicas. Nosso objetivo foi investigar e aferir os níveis de radiação ionizante emitida por equipamentos de cinefluoroscopia. Método: Foram realizados ensaios técnicos para avaliar a taxa de kerma no ar de 8 equipamentos de hemodinâmica. Resultados: Apenas 2 (25 por cento) dos 8 equipamentos apresentavam dosimetria dentro dos limites máximos de segurança. A média das doses foi 65 por cento maior nos equipamentos com tecnologia flat detector. Após aplicação da manutenção supervisionada, verificou-se diminuição média de 42 por cento nos valores dosimétricos. Todos os equipamentos foram aprovados nos ensaios de resolução espacial de alto e baixo contrastes, e a qualidade da imagem foi corroborada pela equipe médica. Conclusão: A maioria dos equipamentos analisados apresentava dosimetria acima dos limites máximos de segurança, particularmente com a tecnologia flat detector. Essas distorções foram corrigidas com medidas de supervisão simples, sem prejuízo à qualidade da imagem. Nossos resultados ressaltam a necessidade de criação de programas institucionais de auqlidade visando à manutenção regular dos equipamentos e à incorporação criteriosa de novas tecnologias no intuito de minimizar os potenciais efeitos deletérios da radiação ionizante, promovendo maior segurança e economia.

BACKGROUND: With the technological evolution and expansion of interventional cardiology, the levels of X-ray exposure of patients and technical staff as well as the number of catheterization procedures have increased considerably. This has an impact on the inherent risk of exposure to ionizing radiation which is still underestimated by many. The levels of exposure must be routinely measured and adjusted. Our objective was to investigate and measure ionizing radiation levels emitted by cath lab X-ray equipments. METHODS: Technical tests were conducted to evaluate the air kerma of 8 X-ray equipments. RESULTS: Only 2 (25%) of the 8 equipments had dosimetry within maximum safety levels. The mean dose was 65% higher in devices with the flat detector technology. After supervised maintenance, there was a mean decrease of 42% in dosimetry values. All equipments were approved by the high and low contrast spatial resolution tests, and the image quality was approved by the medical team. CONCLUSIONS: Most of the equipments evaluated had dosimetry levels exceeding the maximum safety levels, especially those with the flat detector technology. These distortions were corrected by simple monitoring measures, without losses in image quality. Our results emphasizes the need to create institutional quality programs, to keep regular equipment maintenance and to exercise discretion in the incorporation of new technologies to minimize the potential effects of the deleterious effects of ionizing radiation, promoting greater safety and economy.

Radiología diagnóstica en la embarazada: consideraciones sobre exposición a radiación y riesgo del feto / Diagnostic radiology in the pregnant: radiation exposure and risk to the fetus

El uso de exámenes de imágenes para el diagnóstico de condiciones no obstétricas puede ser requerido durante cualquier etapa del embarazo. Existe un riesgo teórico de defectos en el desarrollo fetal, el que se ha considerado no relevante con el nivel de dosis aportada por la radiología diagnóstica habitual. La comprensión de los efectos de la radiación en las diferentes etapas del desarrollo fetal y las dosis aportadas por las diferentes técnicas de imágenes debieran colaborar en la elección del tipo de examen a realizar y del mejor momento para hacerlo.

Diagnostic imaging studies can be required during any phase of the pregnancy for the diagnosis of not obstetric conditions. A theoretical risk of defects in the fetal development exists, but it has been considered insignificant at the dose level used for regular radiology practice. Comprehension of radiation effects over fetal development at different pregnancy stages and the relation between imaging modality and dose can help to make a choice, selecting the best radiologic examination and the best moment to do it.

Enhancement of radiation induced cell death in chicken B lymphocytes by withaferin A.

Withaferin A (WA), a plant withanolide, has shown significant radiosensitizing effect in vitro and in vivo. Inhibition of DNA repair has been suggested as a mechanism of radiosensitization by WA. To test this, the effect of withaferin A on survival of DT40 chicken B-lymphocyte cell line and its repair deficient single gene mutants Rad54-/-, Ku70-/- and double mutant Ku70-/- /Rad54-/- after irradiation was studied. Exponentially growing cells were treated for 1 hr with 5 microM WA and then exposed to different doses of X-rays. Cell survival was studied by clonogenic assay. WA significantly reduced survival of DT40, Ku70-/- and Ku70-/- /Rad54-/-, but not Rad54-/- cells, suggesting that WA enhances radiosensitivity by interfering with homologous repair, the major pathway of DSB repair in these cells. Inhibition of DNA repair is further indicated in a significant decrease in surviving fraction of DT40 cells by post-irradiation incubation with WA. This could have relevance to cancer radiotherapy.

Consideraciones sobre el uso de rayos X en la práctica médica convencional para la necesaria aplicación de normas básicas de seguridad / Considerations about the use of X-rays in the conventional medical practice for necesary aplication of basic security rules

The application maintained and increasing of the explorations with X-rays, consequence of significant development of the engineering together with evolved computacionals methodologies has allowed to reach to the great anatomical majority of locus where it seats the disease. The consequence immediate has been the increase of the exhibition of the patients to ionizing radiations. Different organizations, worried about the health publish, including with it to important societies of Radiology and also to tie international organizations directly related to the governments like the WHO and the OPS. They have emphasized the necessity to generateregulatory conducts destined to introduce the basic rules of the good medical practice. In our country a situation of smaller development in this particular area still persists. Contingencies experienced by general doctors in his professional practice in small town are described. Some situations derived from the use of conventional radiological procedures like mammography and axial computed tomography are presented commenting aspects that do necessary to prevent the doses that receive the patients in order to avoid the expression of stochasticor deterministic effects with high doses of radiation applied with medical intentions. General aspects of radiological procedures related to practices in pediatric patient emphasizing the conditions of increased risk for iatrogenic effects of radiation, particularly in those premature or new borns.