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Glioblastoma (GBM) is an aggressive, common brain cancer known to disrupt redox biology, affecting behavior and DNA integrity. Past research remains inconclusive. To further understand this, an investigation was conducted on physical training’s effects on behavior, redox balance, and genomic stability in GBMA models. Forty-seven male C57BL/6J mice, 60 days old, were divided into GBM and sham groups (n = 15, n = 10, respectively), which were further subdivided into trained (Str, Gtr; n = 10, n = 12) and untrained (Sut, Gut; n = 10, n = 15) subsets. The trained mice performed moderate aerobic exercises on a treadmill five to six times a week for a month while untrained mice remained in their enclosures. Behavior was evaluated using open-field and rotarod tests. Post training, the mice were euthanized and brain, liver, bone marrow, and blood samples were analyzed for redox and genomic instability markers. The results indicated increased latency values in the trained GBM (Gtr) group, suggesting a beneficial impact of exercise. Elevated reactive oxygen species in the parietal tissue of untrained GBM mice (Gut) were reduced post training. Moreover, Gtr mice exhibited lower tail intensity, indicating less genomic instability. Thus, exercise could serve as a promising supplemental GBM treatment, modulating redox parameters and reducing genomic instability.

Summary Uncertainties regarding the factors that influence asphaltene deposition in porous media (e.g., those resulting from oil composition, rock properties, and rock/fluid interaction) strongly affect the prediction of important variables, such as oil production. Besides, some aspects of these predictions are stochastic processes, such as the aggregation phenomenon of asphaltene precipitates. For this reason, a well-defined output from an asphaltene-deposition model might not be feasible. Instead of this, obtaining the probability distribution of important outputs (e.g., permeability reduction and oil production) should be the objective of rigorous modeling of this phenomenon. This probability distribution would support the design of a risk-based policy for the prevention and mitigation of asphaltene deposition. In this paper we aim to present a new approach to assessing the risk of formation damage caused by asphaltene deposition using Monte Carlo simulations. Using this approach, the probability-distribution function of the permeability reduction was obtained. To connect this information to a parameter more related to economic concepts, the probability distribution of the damage ratio (DR) was also calculated, which is the fraction of production loss caused by formation damage. A hypothetical scenario involving a decision in the asphaltene-prevention policy is presented as an application of the method. A novel approach to model the prevention of asphaltene aggregation using inhibitors has been proposed and successfully applied in this scenario.

From the liquid–liquid equilibrium (LLE) data of a linear polymer, an investigation of the Sanchez and Lacombe equation of state (SL-EOS) is performed with the goal of describing the swelling of th...

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Hydrogels are tridimensional elastic hydrophilic cross-linked polymers with the ability to absorb water in a process called swelling. The Flory-Huggins (FH) theory can be applied to model hydrogel swelling with appropriate adjustments. In the literature the FH model parameter is directly estimated from experimental data on swelling. The target of this paper is to evaluate the effect of using parameters estimated from liquid-liquid equilibria of the linear polymer directly in the swelling modeling of the respective cross-linked polymer as these data can be easily found in literature. Three methods that use different equations for the FH parameter and two methods for the mechanical contribution are evaluated. These models were applied to the polymer poly(N-isopropylacrylamide), PNIPA, and compared in three swelling intervals: the volume contraction region; the transition temperature; and the region of volume expansion. The most relevant and important behaviors of each region are shown, analyzed and discussed.

The high CO2 content of Brazil’s pre-salt fields, which may reach values from 20% to 44% molar, presents both a challenge as well as an opportunity. CO2 stripped from the produced gas cannot be released into the atmosphere due to environmental restrictions. Therefore, the whole amount of CO2 produced should be continuously reinjected into the reservoir. This work investigates the effect of CO2 content on the low salinity water alternating CO2 injection technique (CO2LSWAG) using a commercial compositional reservoir simulator. In these field-scale simulations, CO2 is stripped from the produced gas and reinjected into the reservoir. Primary oil recovery methods such as CO2 flooding and LSW flooding are also simulated. Chemical reactions between CO2 and the minerals present in the reservoir are modeled. Wettability change is assumed to be the main mechanism for improved oil recovery due to low salinity water injection. Compositional simulations of CO2 injection usually assume a constant injected gas rate. In this case, CO2 is supposed to come from an external source. In many petroleum reservoirs this assumption is true. Three factors are assessed in the present work. The first one is the natural reservoir pressure, which is the main driving force in primary production. The second factor is the amount of CO2 available for injection. The third one is the wettability change promoted by the reaction involving CO2. It is shown that in primary production, higher CO2 content leads to quicker depletion of the natural energy of the reservoir, leading to lower oil recovery. Nevertheless, higher CO2 content also means that more gas is available for reinjection, potentially leading to increased oil production. Finally, as CO2 reacts with minerals it promotes a change in wettability from an oil-wet to a water-wet state. It is shown that the CO2 content is an important variable to be assessed in a high CO2 content reservoir. Optimal injection practices must take these three aspects into consideration.

Modelling of asphaltene precipitation and deposition in petroleum reservoirs requires adjustable parameters and introduces uncertainty sources. To address the main sources of uncertainty, a two-level full factorial sensitivity analysis was applied to asphaltene precipitation and deposition. Six factors were critically evaluated in the models, three concerning the precipitation phenomenon and the others related to the asphaltene deposition: asphaltene molar content, binary interaction parameters, reference pressure, asphaltene molar volume, surface deposition rate coefficient and flocculation parameters. The effect of these factors on the average of permeability reduction is assessed and their relative importance and relevant interactions were analyzed. Curves of precipitated, flocculated and deposited asphaltene showed that asphaltene deposition caused permeability reduction. Results showed that thermodynamic sources of uncertainty have a more significant effect on the model performance compared to the kinetics parameters ones. This suggests that fitting deposition parameters using experimental permeability reduction data may jeopardize the applicability of these parameters in real field conditions. The aggregation of asphaltene precipitates to form larger particles is modelled using the Kohse and Nghiem flocculation model, one of the most used. Simulations for different conditions were also performed to improve the reliability of the findings. We conclude that reestimation of these model parameters using experimental data of kinetics of asphaltene aggregation is required to provide acceptable description of the aggregation phenomenon.

To verify if systolic bulging of floppy mitral cusps can to elastic behavior of their myxomatous collagen tissue.Five hearts with floppy mitral valves obtained from autopsies were distended with air (20 to 250 mmHg) through a catheter connected to the left ventricle. It was observed if some area of the atrial surface of the coapted cusps showed variable bulging according to the variation of air injection pressures. Molding of those surfaces (gypsum) allowed the same kind of analysis by other four researches. It was analyzed the cut surfaces of these radially sectioned molds. Lately, isolated tendinae chords were submitted to repeated tractions and observed if they exhibited elastic behavior. Histological study defined the presence of collagen myxomatous degeneration and quantified the amount of elastic tissue.In no case it was detected elastic bulding of mitral cusps. Cut surfaces of the molds confirmed that no increment of the prominent areas occurred, even in those regions with extensive, histologically confirmed, myxomatous substitution of the native collagen tissue.Increment of the degree of mitral bulging occurring during ventricular systole can not be ascertained to cusp elasticity but probably to papilar muscle traction.

To verify whether accentuated reductions of left ventricular volume lead to mitral valve prolapse.Seven mongrel dogs were bled through the internal jugular vein, the systolic systemic pressure being kept between 100 and 140 mmHg by means of continuous infusion of dopamine; the inferior vena cava vein, in tree other dogs, was partially obstructed for 4 to 6 seconds; epicardial echocardiography was carried out in all cases.Reductions of volemia were about 50% of the estimated total blood volume. Systolic internal diameter of left ventricle decreased about 25% and systolic ostial diameter, about 12.5%. Three out of seven died suddenly from arrhythmia before one has reached a significant decrease in total blood volume; one showed momentary mitral valve prolapse, during a period of hypotension; however, this prolapse disappeared completely when systemic blood pressure was restored by increasing the dopamine dosage; one dog had slight systolic displacement of the anterior cusp toward left atrium (0.5mm) and the last two showed no change; one out of 3 dogs submitted to partial constriction of inferior vena cava had systolic displacement of anterior cusp of 1mm; in one case there was an equivalent degree of displacement of the anterior cusp toward the left ventricle and in the last one no change was detected. In all dogs there was a change in the dynamics of mitral valve closure: with accentuated reduction of left ventricular volume the posterior cusp became less mobile, the anterior cusp being the principal responsible for the systolic ostial occlusion.Accentuated reduction of dog's left ventricular volume does not, necessarily, cause mitral valve prolapse but only slight displacement of the anterior cusp toward the left atrium in some animals or no displacement at all.

To evaluate the pressoric behaviour in chagasic patients in different stages of myocardial damage and to correlate Chagas' disease with arterial hypertension.The arterial blood pressure of 644 chagasic patients surveyed in the HC-UNICAMP, with arterial hypertension or not, associated with the stage of myocardial dysfunction was evaluated. This group was compared with 370 hypertensive patients without Chagas' disease. Both were divided by sex and age. The results were evaluated by covariance analysis and the significance was pointed at p0.05.The chagasic group presented a high prevalence of arterial hypertension with 16.8% in the clinical phase I, 27.8% in the phase II and 34% in the III. Both hypertensive and nonhypertensive chagasic patients had a significant drop in clinical phase I after the age of 30 years. The chagasic patients classified in phase II presented a high prevalence between 30-50 years, not associated with the pressoric behaviour and/or sex. The symptomatic myocardial dysfunction (phase III) was uncommon below 40 years old in chagasic group with hypertension or not, but presented a highest prevalence in male hypertensive chagasic patients above 50 years old.The study demonstrated a more usual association of Chagas' disease and hypertension in patients with symptomatic myocardial dysfunction, above 50 years old. This find evidenciates the somatory and progressive effect of both diseases. It is possible that the pathogenic mechanisms of Chagas' disease contributed to the increment of the arterial blood pressure.

Studying the mitral valve in chronic Chagas' heart disease, searching a possible cause effect relationship between this condition and valve prolapse.Seventeen hearts were surveyed from individuals exhibiting chronic chagasic cardiopathy, 11 males and 6 females, aged between 31-84 (average 54) years. The hearts came from necropsies carried out until a year before. Properly preserved samples were analyzed macro and microscopically. Fragments were excised from the mitral valve papillary muscles, anterior, lateral and posterior regions of the left ventricle, interventricular septum, free wall of right ventricle and atrium walls.Chronic myocarditis was found ill all the samples (mild in 6 of them, moderate in 7 and severe in 4). Also, the papillary muscles exhibited myocarditis in all of the samples, and in 15 of them the degree of severity was equal to or superior than the observed in degree other regions of the heart.The chronic chagasic cardiopathy, the papillary muscle constitute a frequent site of myocarditis. This fact must be held in mind when one discusses the pathogenesis of the prolapse of the valve.

Thirty-two monkeys were captured and adapted to laboratory conditions captives isolated. They were submitted to multiple xenodiagnosis which were negative. Twelve were infected intraperitoneally with different strains of T. cruzi (1.10(5) to 5.10(6)). Twenty were the control group. Between on to six years both the control group and the infected monkeys, were submitted to xenodiagnosis, serological testing clinical examination and electrocardiography. The clinical examination and the electrocardiogram were always normal. The monkey were autopsied and histological examination detected in the infected group four monkeys with evidence of disease: one with parasites in the tissue and three with chronic myocarditis. Parasitaemia was in 66.66% of the monkeys in the acute phase and the serology was positive in 91.66% in the chronic phase. The authors concluded that Cebus monkeys were not susceptible to the development of the disease but they could be utilized to maintain of such strains and studies of serological research in long-terms infections.

Woman, 76 years old with mitral stenosis died due to peripheral arterial embolism. The necropsy identified left atrial to coronary sinus fenestration associated with stenosis of the coronary sinus ostium and rheumatic mitral stenosis.

The relative positions of the left ventricular apex and base in end-diastole (ED) and end-systole (ES) were determined in a group of normal individuals using cross-sectional echocardiography (group A) and in a group of patients with normal hemodynamics and angiographic parameters using cine-computed tomography (group B). In both groups no change was detected in the position of the epicardial aspect of the apex from ED to ES. The base moved in direction of the apex by 10.2% +/- 1.9% (mean +/- standard deviation) of the longitudinal dimension of the chamber in group A and by 12.9% +/- 5.1% in group B. In both groups the apical cavity was obliterated by the peri-apical walls. Apical obliteration is responsible for the apparent movement of the apical segment seen in cineventriculography.

Relato de um caso de astrocitoma grau II com metástase medular ao nível da terceira vértebra dorsal. O nódulo intradural determinou sinais e sintomas de compressão medular. O diagnóstico clínico foi confirmado por mielografia descendente com lipiodol e mielocintilografia com I131 - albumina. A paciente foi submetida a laminectomia para exerese da metástase. A revisão da literatura mostra que o fator mais importante para a ocorrência das metástase dos tumores encefálicos é a invasão do sistema ventricular e/ou espaço subaracnóideo periencefálico pela neoplasia, sem relação com o ato operatório. A case of a right frontal astrocytoma with spinal metastatic lesion in the region of the third dorsal vertebra is reported. The metastatic nodule was removed six months after the craniotomy. In the literature concerning to the dissemination of tumors cells is suggested that there is not a causal relationship between CSF seeding and operative intervention. Acess to the ventricular system or basal cisterns is of primary importance in the production of metastases.

The post mortem findings in 200 autopsies were compared with the clinical diagnoses. Twenty diseases were analysed with respect to clinico-pathological correlation. In relation to the respective totals the diseases most frequently missed clinically were (false negative) pyelonephritis (100%), pulmonary embolus (87.50%) and bronchopneumonia (58.16%). In relation to the respective totals the clinical diagnoses less frequently confirmed (false positive) were tuberculosis (69.56%), paracoccidioidomycosis (57.14%), sepsis (53.13%) and Chagas' disease (44.44%). There was clinicopathological agreement in 97 autopsies (48.50%). In 19 cases (9.50%) if the diagnostic error had been detected during life this probably would have changes the prognosis. The findings are discussed in the light of previous studies. The importance of routine post-mortem examination and clinico-pathological correlation is stressed.

A case of a right frontal astrocytoma with spinal metastatic lesion in the region of the third dorsal vertebra is reported. The metastatic nodule was removed six months after the craniotomy. In the literature concerning to the dissemination of tumors cells is suggested that there is not a causal relationship between CSF seeding and operative intervention. Access to the ventricular system or basal cisterns is of primary importance in the production of metastases.