Interaction of magnetic nanoparticles with U87MG cells studied by synchrotron radiation X-ray fluorescence techniques

International audienceSynchrotron radiation (SR) X-ray microscopy combined with X-ray fluorescence (XRF) microspectroscopy provides unique information that have pushed the frontiers of biological research, particularly when investigating intracellular mechanisms. This work reports an SR-XRF microspectroscopy investigation on the distribution and the potential toxicity of Fe 2 O 3 and CoFe 2 O 4 nanoparticles (NPs) in U87MG glioblastoma-astrocytoma cells. The U87MG cells exposed to NPs concentrations ranging from 5 to 250 mg/ml for 24 h were analyzed in order to monitor both morphological and chemical changes. The SR-XRF maps complemented with XRM absorption and phase contrast images have revealed different intracellular distribution patterns for the two nanoparticles types allowing different mechanism of toxicity to be deduced

Levels of Angiopoietin 2 Are Predictive for Mortality in Patients Infected With Yellow Fever Virus

In 2018 there was a large yellow fever outbreak in São Paulo, Brazil, with a high fatality rate. Yellow fever virus can cause, among other symptoms, hemorrhage and disseminated intravascular coagulation, indicating a role for endothelial cells in disease pathogenesis. Here, we conducted a case-control study and measured markers related to endothelial damage in plasma and its association with mortality. We found that angiopoietin 2 is strongly associated with a fatal outcome and could serve as a predictive marker for mortality. This could be used to monitor severe cases and provide care to improve disease outcome

Corsi's block-tapping test: some characteristics of the spatial path which influence memory

By using a sequence of digits it is possible to indicate the path of Corsi's block-tapping test by drawing a line to join the central points of the cubes which make up the sequence. By doing this one can analyze the sequence of digits according to quantitative parameters. There were three characteristics of the spatial path taken into consideration in this research: the number of cubes which constitute a series of digits, the number of times the path intersected itself, and the length of the path measured in millimeters. The experiment, carried out with 70 university students, showed that all three factors were significant on analysis of variance, and also that there were differences between the sexes, the men performing better. No interactions were significant. Despite this, additional significant differences were found among the series with the same number of cubes, intersections, and length, meaning that other variables influence the difficulty of the spatial path

Experimental analysis on the performance of a turbocharger compressor in the unstable operating region and close to the surge limit

To make simulation models able to accurately predict engine performance, a better understanding of compressor steady flow performance over an extended range must be accomplished thanks to the availability of specialized test facility and measuring equipment. Besides, the correct surge line position is another important aspect to be considered to optimize engine-turbocharger matching calculation. In the paper the results of an experimental investigation developed on a turbocharger compressor for heavy duty vehicle application is presented. The study was focused on the definition of surge line position adopting different methods and on the evaluation of compressor performance over an extended range, taking into account compressor behavior in stable and unstable region

Hemorrhagic uterine necrosis after surgical vessel ligation and B-Lynch suture in persistent post-cesarean uterine atony: case report and review of literature

Uterine necrosis is a rare life-threatening condition reported in few case reports and series, associated with uterine artery embolization for uterine fibroids or postpartum hemorrhage. We report a hemorrhagic uterine necrosis in a nulliparous 35 years-old woman underwent cesarean section at 40+1 weeks of gestation for obstructed labor, presenting post-partum persisting bleeding and uterine atony and congestion. Bleeding stopped only after placement of two set of compressive sutures, curettage of uterine cavity and placement of Bakri Balloon but the uterine body never contracted and become congested. Notwithstanding an effective antibiotic therapy, the patient developed an intermittent fever and signs of severe anemia. Clinical and radiological diagnosis with CT and MRI scan were compatible with uterine necrosis characterized by hemorrhagic infarction of the uterine wall and decomposition of its muscular tissue. Hysterectomy was discussed with patient and performed on day 32 after C-section. Uterine apoplexy, a rare life-threatening disease, was detected with CT by lack of uterine contrast enhancement and a gas-filled uterine cavity and necrosis was confirmed with MRI by showing fluid degeneration of the myometrium. Failure to recognize a necrotic uterus on imaging can cause delayed hysterectomy, which is mandatory and potentially life-saving

Hemorrhagic uterine necrosis after surgical vessel ligation and B-Lynch suture in persistent post-cesarean uterine atony: case report and review of literature

Uterine necrosis is a rare life-threatening condition reported in few case reports and series, associated with uterine artery embolization for uterine fibroids or postpartum hemorrhage. We report a hemorrhagic uterine necrosis in a nulliparous 35 years-old woman underwent cesarean section at 40+1 weeks of gestation for obstructed labor, presenting post-partum persisting bleeding and uterine atony and congestion. Bleeding stopped only after placement of two set of compressive sutures, curettage of uterine cavity and placement of Bakri Balloon but the uterine body never contracted and become congested. Notwithstanding an effective antibiotic therapy, the patient developed an intermittent fever and signs of severe anemia. Clinical and radiological diagnosis with CT and MRI scan were compatible with uterine necrosis characterized by hemorrhagic infarction of the uterine wall and decomposition of its muscular tissue. Hysterectomy was discussed with patient and performed on day 32 after C-section. Uterine apoplexy, a rare life-threatening disease, was detected with CT by lack of uterine contrast enhancement and a gas-filled uterine cavity and necrosis was confirmed with MRI by showing fluid degeneration of the myometrium. Failure to recognize a necrotic uterus on imaging can cause delayed hysterectomy, which is mandatory and potentially life-saving

Analise da aplicacao da cintigrafia mamaria com 99mTC-tetrofosmin e da mamografia convencional por raios X no diagnostico diferencial das lesoes mamarias

O objetivo deste estudo foi avaliar o uso potencial da cintigrafia mamaria com 99m Tc-Tetrofosmin na deteccao das neoplasias mamarias malignas em uma populacao de alta prevalencia, atraves da comparacao com a mamografia bilateral por raios X e do resultado das biopsias das lesoes mamarias. Em 50 pacientes do sexo feminino ( media etaria : 53,7 + 11,9 anos ) realizaram-se a mamografia bilateral por raios X e a cintigrafia mamaria. As cintigrafias foram iniciadas 30 minutos apos a administracao endovenosa de 25 miliCuries ( 925 MegaBequereis ) de 99m Tc-Tetrofosmin. Em uma gama camera SPECT foram coletadas imagens planares das projecoes anterior de torax e obliquas posteriores de cada mama. A histopatologia das lesoes foi feita atraves de 44 amostras colhidas em cirurgia e 6 amostras de aspiracao com agulha .Verificou-se a presenca de 16 pacientes com patologias mamarias benignas (32 %) e 34 pacientes (68%) portadoras de neoplasia mamaria maligna. A mamografia resultou em 7 estudos indeterminados, 30 verdadeiros positivos ( VP ), 2 verdadeiros negativos ( VN ), 10 falsos positivos ( FP ) e 1 falso negativo ( FN ). A cintigrafia mamaria apresentou 3 estudos indeterminados, 30 VP, 14 VN, 1 FP e 2 FN. o calculo da sensibilidade ( S ) e da especificidade ( E ) foi realizado para a mamografia, obtendo-se S de 97 % e E de 17 % . O mesmo calculo foi realizado para a cintigrafia mamaria que apresentou S de 94 % e E de 93 % . Os mesmos parametros foram estudados separadamente nas lesoes palpaveis e nao palpaveis, onde a cintigrafia mamaria registrou valores de especificidade superiores aos da mamografia. Concluuiu-se que a cintigrafia mamaria com 99mTc-Tetrofosmin detecta a neoplasia mamaria maligna com sensibilidade semelhante a mamografia por raios X e apresenta especificidade maior, especialmente nas lesoes nao palpaveis. A indicacao da cintigrafia mamaria com 99m Tc-Tetrofosmin deve ser realizada como complemento as mamografias das lesoes nao palpaveisBV UNIFESP: Teses e dissertaçõe