949 resultados para Cortical Blood-flow
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PURPOSE: Thoracic fat has been associated with an increased risk of coronary artery disease (CAD). As endothelium-dependent vasoreactivity is a surrogate of cardiovascular events and is impaired early in atherosclerosis, we aimed at assessing the possible relationship between thoracic fat volume (TFV) and endothelium-dependent coronary vasomotion. METHODS: Fifty healthy volunteers without known CAD or major cardiovascular risk factors (CRFs) prospectively underwent a (82)Rb cardiac PET/CT to quantify myocardial blood flow (MBF) at rest, and MBF response to cold pressor testing (CPT-MBF) and adenosine (i.e., stress-MBF). TFV was measured by a 2D volumetric CT method and common laboratory blood tests (glucose and insulin levels, HOMA-IR, cholesterol, triglyceride, hsCRP) were performed. Relationships between CPT-MBF, TFV and other CRFs were assessed using non-parametric Spearman rank correlation testing and multivariate linear regression analysis. RESULTS: All of the 50 participants (58 ± 10y) had normal stress-MBF (2.7 ± 0.6 mL/min/g; 95 % CI: 2.6-2.9) and myocardial flow reserve (2.8 ± 0.8; 95 % CI: 2.6-3.0) excluding underlying CAD. Univariate analysis revealed a significant inverse relation between absolute CPT-MBF and sex (ρ = -0.47, p = 0.0006), triglyceride (ρ = -0.32, p = 0.024) and insulin levels (ρ = -0.43, p = 0.0024), HOMA-IR (ρ = -0.39, p = 0.007), BMI (ρ = -0.51, p = 0.0002) and TFV (ρ = -0.52, p = 0.0001). MBF response to adenosine was also correlated with TFV (ρ = -0.32, p = 0.026). On multivariate analysis, TFV emerged as the only significant predictor of MBF response to CPT (p = 0.014). CONCLUSIONS: TFV is significantly correlated with endothelium-dependent and -independent coronary vasomotion. High TF burden might negatively influence MBF response to CPT and to adenosine stress, even in persons without CAD, suggesting a link between thoracic fat and future cardiovascular events.
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BACKGROUND: The unique situation of the liver with arterial and venous blood supply and the dependency of the tumor on the arterial blood flow make this organ an ideal target for intrahepatic catheter-based therapies. Main forms of treatment are classical bland embolization (TAE) cutting the blood flow to the tumors, chemoembolization (TACE) inducing high chemotherapy concentration in tumors, and radioembolization (TARE) without embolizing effect but very high local radiation. These different forms of therapies are used in different centers with different protocols. This overview summarizes the different forms of treatment, their indications and protocols, possible side effects, and available data in patients with non-colorectal liver tumors. METHODS: A research in PubMed was performed. Mainly clinical controlled trials were reviewed. The search terms were 'embolization liver', 'TAE', 'chemoembolization liver', 'TACE', 'radioembolization liver', and 'TARE' as well as 'chemosaturation' and 'TACP' in the indications 'breast cancer', 'neuroendocrine', and 'melanoma'. All reported studies were analyzed for impact and reported according to their clinical relevance. RESULTS: The main search criteria revealed the following results: 'embolization liver + breast cancer', 122 results, subgroup clinical trials 16; 'chemoembolization liver + breast cancer', 62 results, subgroup clinical trials 11; 'radioembolization liver + breast cancer', 37 results, subgroup clinical trials 3; 'embolization liver + neuroendocrine', 283 results, subgroup clinical trials 20; 'chemoembolization liver + neuroendocrine', 202 results, subgroup clinical trials 9; 'radioembolization liver + neuroendocrine', 64 results, subgroup clinical trials 9; 'embolization liver + melanoma', 79 results, subgroup clinical trials 15; 'chemoembolization liver + melanoma', 60 results, subgroup clinical trials 14; 'radioembolization liver + melanoma', 18 results, subgroup clinical trials 3. The term 'chemosaturation liver' was tested without indication since only few publications exist and provided us with five results and only one clinical trial. CONCLUSION: Despite many years of clinical use and documented efficacy on intra-arterial treatments of the liver, there are still only a few prospective multicenter trials with many different protocols. To guarantee the future use of these efficacious therapies, especially in the light of many systemic or surgical therapies in the treatment of non-colorectal liver metastases, further large randomized trials and transparent guidelines need to be established.
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Cerebral energy dysfunction has emerged as an important determinant of prognosis following traumatic brain injury (TBI). A number of studies using cerebral microdialysis, positron emission tomography, and jugular bulb oximetry to explore cerebral metabolism in patients with TBI have demonstrated a critical decrease in the availability of the main energy substrate of brain cells (i.e., glucose). Energy dysfunction induces adaptations of cerebral metabolism that include the utilization of alternative energy resources that the brain constitutively has, such as lactate. Two decades of experimental and human investigations have convincingly shown that lactate stands as a major actor of cerebral metabolism. Glutamate-induced activation of glycolysis stimulates lactate production from glucose in astrocytes, with subsequent lactate transfer to neurons (astrocyte-neuron lactate shuttle). Lactate is not only used as an extra energy substrate but also acts as a signaling molecule and regulator of systemic and brain glucose use in the cerebral circulation. In animal models of brain injury (e.g., TBI, stroke), supplementation with exogenous lactate exerts significant neuroprotection. Here, we summarize the main clinical studies showing the pivotal role of lactate and cerebral lactate metabolism after TBI. We also review pilot interventional studies that examined exogenous lactate supplementation in patients with TBI and found hypertonic lactate infusions had several beneficial properties on the injured brain, including decrease of brain edema, improvement of neuroenergetics via a "cerebral glucose-sparing effect," and increase of cerebral blood flow. Hypertonic lactate represents a promising area of therapeutic investigation; however, larger studies are needed to further examine mechanisms of action and impact on outcome.
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Previous studies reported enhanced cerebrovascular CO2 reactivity upon ascent to high altitude using linear models. However, there is evidence that this response may be sigmoidal in nature. Moreover, it was speculated that these changes at high altitude are mediated by alterations in acid-base buffering. Accordingly, we reanalyzed previously published data to assess middle cerebral blood flow velocity (MCAv) responses to modified rebreathing at sea level (SL), upon ascent (ALT1) and following 16 days of acclimatization (ALT16) to 5260 m in 21 lowlanders. Using sigmoid curve fitting of the MCAv responses to CO2, we found the amplitude (95 vs. 129%, SL vs. ALT1, 95% confidence intervals (CI) [77, 112], [111, 145], respectively, P = 0.024) and the slope of the sigmoid response (4.5 vs. 7.5%/mmHg, SL vs. ALT1, 95% CIs [3.1, 5.9], [6.0, 9.0], respectively, P = 0.026) to be enhanced at ALT1, which persisted with acclimatization at ALT16 (amplitude: 177, 95% CI [139, 215], P < 0.001; slope: 10.3%/mmHg, 95% CI [8.2, 12.5], P = 0.003) compared to SL. Meanwhile, the sigmoidal response midpoint was unchanged at ALT1 (SL: 36.5 mmHg; ALT1: 35.4 mmHg, 95% CIs [34.0, 39.0], [33.1, 37.7], respectively, P = 0.982), while it was reduced by ~7 mmHg at ALT16 (28.6 mmHg, 95% CI [26.4, 30.8], P = 0.001 vs. SL), indicating leftward shift of the cerebrovascular CO2 response to a lower arterial partial pressure of CO2 (PaCO2) following acclimatization to altitude. Sigmoid fitting revealed a leftward shift in the midpoint of the cerebrovascular response curve which could not be observed with linear fitting. These findings demonstrate that there is resetting of the cerebrovascular CO2 reactivity operating point to a lower PaCO2 following acclimatization to high altitude. This cerebrovascular resetting is likely the result of an altered acid-base buffer status resulting from prolonged exposure to the severe hypocapnia associated with ventilatory acclimatization to high altitude.
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PURPOSE: Obstructive sleep apnea syndrome (OSA) increases the risk of cardiovascular disease. We aimed at evaluating the effect of continuous positive airway pressure (CPAP) treatment on coronary endothelium-dependent vasoreactivity in OSA patients by quantifying myocardial blood flow (MBF) response to cold pressure testing (CPT). METHODS: In the morning after polysomnography (PSG), all participants underwent a dynamic (82)Rb cardiac positron emitting tomography/computed tomography (PET/CT) scan at rest, during CPT and adenosine stress. PSG and PET/CT were repeated at least 6 weeks after initiating CPAP treatment. OSA patients were compared to controls and according to response to CPAP. Patients' characteristics and PSG parameters were used to determine predictors of CPT-MBF. RESULTS: Thirty-two untreated OSA patients (age 58 ± 13 years, 27 men) and 9 controls (age 62 ± 5 years, 4 men) were enrolled. At baseline, compared to controls (apnea-hypopnea index (AHI) = 5.3 ± 2.6/h), untreated OSA patients (AHI = 48.6 ± 19.7/h) tend to have a lower CPT-MBF (1.1 ± 0.2 mL/min/g vs. 1.3 ± 0.4 mL/min/g, p = 0.09). After initiating CPAP, CPT-MBF was not different between well-treated patients (AHI <10/h) and controls (1.3 ± 0.3 mL/min/g vs. 1.3 ± 0.4 mL/min/g, p = 0.83), but it was lower for insufficiently treated patients (AHI ≥10/h) (0.9 ± 0.2 mL/min/g vs. 1.3 ± 0.4 mL/min/g, p = 0.0045). CPT-MBF was also higher in well-treated than in insufficiently treated patients (1.3 ± 0.3 mL/min/g vs. 0.9 ± 0.2 mL/min/g, p = 0.001). Mean nocturnal oxygen saturation (β = -0.55, p = 0.02) and BMI (β = -0.58, p = 0.02) were independent predictors of CPT-MBF in OSA patients. CONCLUSIONS: Coronary endothelial vasoreactivity is impaired in insufficiently treated OSA patients compared to well-treated patients and controls, confirming the need for CPAP optimization.
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The transport of macromolecules, such as low-density lipoprotein (LDL), and their accumulation in the layers of the arterial wall play a critical role in the creation and development of atherosclerosis. Atherosclerosis is a disease of large arteries e.g., the aorta, coronary, carotid, and other proximal arteries that involves a distinctive accumulation of LDL and other lipid-bearing materials in the arterial wall. Over time, plaque hardens and narrows the arteries. The flow of oxygen-rich blood to organs and other parts of the body is reduced. This can lead to serious problems, including heart attack, stroke, or even death. It has been proven that the accumulation of macromolecules in the arterial wall depends not only on the ease with which materials enter the wall, but also on the hindrance to the passage of materials out of the wall posed by underlying layers. Therefore, attention was drawn to the fact that the wall structure of large arteries is different than other vessels which are disease-resistant. Atherosclerosis tends to be localized in regions of curvature and branching in arteries where fluid shear stress (shear rate) and other fluid mechanical characteristics deviate from their normal spatial and temporal distribution patterns in straight vessels. On the other hand, the smooth muscle cells (SMCs) residing in the media layer of the arterial wall respond to mechanical stimuli, such as shear stress. Shear stress may affect SMC proliferation and migration from the media layer to intima. This occurs in atherosclerosis and intimal hyperplasia. The study of blood flow and other body fluids and of heat transport through the arterial wall is one of the advanced applications of porous media in recent years. The arterial wall may be modeled in both macroscopic (as a continuous porous medium) and microscopic scales (as a heterogeneous porous medium). In the present study, the governing equations of mass, heat and momentum transport have been solved for different species and interstitial fluid within the arterial wall by means of computational fluid dynamics (CFD). Simulation models are based on the finite element (FE) and finite volume (FV) methods. The wall structure has been modeled by assuming the wall layers as porous media with different properties. In order to study the heat transport through human tissues, the simulations have been carried out for a non-homogeneous model of porous media. The tissue is composed of blood vessels, cells, and an interstitium. The interstitium consists of interstitial fluid and extracellular fibers. Numerical simulations are performed in a two-dimensional (2D) model to realize the effect of the shape and configuration of the discrete phase on the convective and conductive features of heat transfer, e.g. the interstitium of biological tissues. On the other hand, the governing equations of momentum and mass transport have been solved in the heterogeneous porous media model of the media layer, which has a major role in the transport and accumulation of solutes across the arterial wall. The transport of Adenosine 5´-triphosphate (ATP) is simulated across the media layer as a benchmark to observe how SMCs affect on the species mass transport. In addition, the transport of interstitial fluid has been simulated while the deformation of the media layer (due to high blood pressure) and its constituents such as SMCs are also involved in the model. In this context, the effect of pressure variation on shear stress is investigated over SMCs induced by the interstitial flow both in 2D and three-dimensional (3D) geometries for the media layer. The influence of hypertension (high pressure) on the transport of lowdensity lipoprotein (LDL) through deformable arterial wall layers is also studied. This is due to the pressure-driven convective flow across the arterial wall. The intima and media layers are assumed as homogeneous porous media. The results of the present study reveal that ATP concentration over the surface of SMCs and within the bulk of the media layer is significantly dependent on the distribution of cells. Moreover, the shear stress magnitude and distribution over the SMC surface are affected by transmural pressure and the deformation of the media layer of the aorta wall. This work reflects the fact that the second or even subsequent layers of SMCs may bear shear stresses of the same order of magnitude as the first layer does if cells are arranged in an arbitrary manner. This study has brought new insights into the simulation of the arterial wall, as the previous simplifications have been ignored. The configurations of SMCs used here with elliptic cross sections of SMCs closely resemble the physiological conditions of cells. Moreover, the deformation of SMCs with high transmural pressure which follows the media layer compaction has been studied for the first time. On the other hand, results demonstrate that LDL concentration through the intima and media layers changes significantly as wall layers compress with transmural pressure. It was also noticed that the fraction of leaky junctions across the endothelial cells and the area fraction of fenestral pores over the internal elastic lamina affect the LDL distribution dramatically through the thoracic aorta wall. The simulation techniques introduced in this work can also trigger new ideas for simulating porous media involved in any biomedical, biomechanical, chemical, and environmental engineering applications.
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Increased production of vasoconstrictive prostanoids, such as thromboxane A2 (TXA2 ), contributes to endothelial dysfunction and increased hepatic vascular tone in cirrhosis. TXA2 induces vasoconstriction by way of activation of the thromboxane-A2 /prostaglandin-endoperoxide (TP) receptor. This study investigated whether terutroban, a specific TP receptor blocker, decreases hepatic vascular tone and portal pressure in rats with cirrhosis due to carbon tetrachloride (CCl4 ) or bile duct ligation (BDL). Hepatic and systemic hemodynamics, endothelial dysfunction, liver fibrosis, hepatic Rho-kinase activity (a marker of hepatic stellate cell contraction), and the endothelial nitric oxide synthase (eNOS) signaling pathway were measured in CCl4 and BDL cirrhotic rats treated with terutroban (30 mg/kg/day) or its vehicle for 2 weeks. Terutroban reduced portal pressure in both models without producing significant changes in portal blood flow, suggesting a reduction in hepatic vascular resistance. Terutroban did not significantly change arterial pressure in CCl4 -cirrhotic rats but decreased it significantly in BDL-cirrhotic rats. In livers from CCl4 and BDL-cirrhotic terutroban-treated rats, endothelial dysfunction was improved and Rho-kinase activity was significantly reduced. In CCl4 -cirrhotic rats, terutroban reduced liver fibrosis and decreased alpha smooth muscle actin (α-SMA), collagen-I, and transforming growth factor beta messenger RNA (mRNA) expression without significant changes in the eNOS pathway. In contrast, no change in liver fibrosis was observed in BDL-cirrhotic rats but an increase in the eNOS pathway. CONCLUSION: Our data indicate that TP-receptor blockade with terutroban decreases portal pressure in cirrhosis. This effect is due to decreased hepatic resistance, which in CCl4 -cirrhotic rats was linked to decreased hepatic fibrosis, but not in BDL rats, in which the main mediator appeared to be an enhanced eNOS-dependent vasodilatation, which was not liver-selective, as it was associated with decreased arterial pressure. The potential use of terutroban for portal hypertension requires further investigation.
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Improve the prediction of the vital and functional prognosis of comatose patients suffering from anoxic-ischemic encephalopathy after successful resuscitation from a cardiac arrest, addmitted to the Intensive Care and Coronary Units of the Dr. Josep Trueta Hospital, based on clinical, neurophysiological and biochemical results.The results of these different tests, revised and combined all together, will improve the prediction of the patients' prognosis, leading to an accurate vital and functional outcome, as they only have been studied separately so far. Anoxia is the third most frequent cause of coma, and the most common cause of post-anoxic coma in adults is the cardiac arrest. The incidence of hypoxic-ischemic brain injury is not well known, but it is certain that cardiac arrest, the most common cause of post-anoxic coma, affects approximately 24000 to 50000 Spanish people every year, most of them occuring out of the hospital. A cardiac arrest is the abrupt cessation of normal circulation of the blood due to failure of the heart to contract effectively during systole. It is different from, but may be caused by, a heart attack or myocardial infarction, where blood flow to the still-beating heart is interrupted. Arrested blood circulation prevents delivery of oxygen to all parts of the body. Cerebral hypoxia, or lack of oxygen supply to the brain, causes victims to lose consciousness and to stop normal breathing, although agonal breathing may still occur. Brain injury is likely if cardiac arrest is untreated for more than five minutes
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BACKGROUND AND AIMS: Liver stiffness is increasingly used in the non-invasive evaluation of chronic liver diseases. Liver stiffness correlates with hepatic venous pressure gradient (HVPG) in patients with cirrhosis and holds prognostic value in this population. Hence, accuracy in its measurement is needed. Several factors independent of fibrosis influence liver stiffness, but there is insufficient information on whether meal ingestion modifies liver stiffness in cirrhosis. We investigated the changes in liver stiffness occurring after the ingestion of a liquid standard test meal in this population. METHODS: In 19 patients with cirrhosis and esophageal varices (9 alcoholic, 9 HCV-related, 1 NASH; Child score 6.9±1.8), liver stiffness (transient elastography), portal blood flow (PBF) and hepatic artery blood flow (HABF) (Doppler-Ultrasound) were measured before and 30 minutes after receiving a standard mixed liquid meal. In 10 the HVPG changes were also measured. RESULTS: Post-prandial hyperemia was accompanied by a marked increase in liver stiffness (+27±33%; p<0.0001). Changes in liver stiffness did not correlate with PBF changes, but directly correlated with HABF changes (r = 0.658; p = 0.002). After the meal, those patients showing a decrease in HABF (n = 13) had a less marked increase of liver stiffness as compared to patients in whom HABF increased (n = 6; +12±21% vs. +62±29%,p<0.0001). As expected, post-prandial hyperemia was associated with an increase in HVPG (n = 10; +26±13%, p = 0.003), but changes in liver stiffness did not correlate with HVPG changes. CONCLUSIONS: Liver stiffness increases markedly after a liquid test meal in patients with cirrhosis, suggesting that its measurement should be performed in standardized fasting conditions. The hepatic artery buffer response appears an important factor modulating postprandial changes of liver stiffness. The post-prandial increase in HVPG cannot be predicted by changes in liver stiffness.
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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL, OMIM #125310) is an inherited vascular disease. The main symptoms include migraineous headache, recurrent strokes and progressive cognitive impairment. CADASIL is caused by mutations in the NOTCH3 gene which result in degeneration of vascular smooth muscle cells, arteriolar stenosis and impaired cerebral blood flow. The aims of this study were assessment of the genetic background of Finnish and Swedish CADASIL patients, analysis of genetic and environmental factors that may influence the phenotype, and identification of the optimal diagnostic strategy. The majority of Finnish CADASIL patients carry the p.Arg133Cys mutation. Haplotype analysis of 18 families revealed a region of linkage disequilibrium around the NOTCH3 locus, which is evidence for a founder effect and a common ancestral mutation. Despite the same mutational background, the clinical course of CADASIL is highly variable between and even within families. The association of several genetic factors with the phenotypic variation was investigated in 120 CADASIL patients. Apolipoprotein E allele 4 was associated with earlier occurrence of strokes, especially in younger patients. Study of a pair of monozygotic twins with CADASIL revealed environmental factors which may influence the phenotype, i.e. smoking, statin medication and physical activity. Knowledge of these factors is useful, since life-style choices may influence the disease progression. The clinical CADASIL diagnosis can be confirmed by detection of either the NOTCH3 mutation or granular osmiophilic material by electron microscopy in skin biopsy, although the sensitivity estimates have been contradictory. Comparison of these two methods in a group of 131 diagnostic cases from Finland, Sweden and France demonstrated that both methods are highly sensitive and reliable.
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Glucose transporter 2 (GLUT2; gene name SLC2A2) has a key role in the regulation of glucose dynamics in organs central to metabolism. Although GLUT2 has been studied in the context of its participation in peripheral and central glucose sensing, its role in the brain is not well understood. To decipher the role of GLUT2 in brain development, we knocked down slc2a2 (glut2), the functional ortholog of human GLUT2, in zebrafish. Abrogation of glut2 led to defective brain organogenesis, reduced glucose uptake and increased programmed cell death in the brain. Coinciding with the observed localization of glut2 expression in the zebrafish hindbrain, glut2 deficiency affected the development of neural progenitor cells expressing the proneural genes atoh1b and ptf1a but not those expressing neurod. Specificity of the morphant phenotype was demonstrated by the restoration of brain organogenesis, whole-embryo glucose uptake, brain apoptosis, and expression of proneural markers in rescue experiments. These results indicate that glut2 has an essential role during brain development by facilitating the uptake and availability of glucose and support the involvement of glut2 in brain glucose sensing.
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Children with sickle cell anemia (SCA) are at increased risk of stroke. Elevated blood-flow velocities in the middle cerebral artery detected by Transcranial Doppler (TCD) are a good predictor of stroke risk in these children. Velocities obtained by TCD are measured by using a specific parameter, the time-averaged mean of the maximum velocity (TAMM). Children with TAMM velocities ≥200 cm/sec are at high risk of stroke, and transfusions as primary prevention might be done. Transcranial Doppler-imaging (TCDI) is now widely available and it allows the visualization of intracranial vessels.Few studies have compared the TAMM in TCD and TCDI, and no studies have established a cutoff point for TAMM in TCDI equivalent to the STOP criteria of “normal”, “conditional” and “abnormal”, which could predict a high risk of stroke in children with SCAObjectives: To compare the TAMM velocity obtained by TCDI with the TAMM velocity obtained with TCD in the middle cerebral artery, and to determine a cutoff point for TAMM in TCDI that could predict a high risk of stroke in children with SCAMethods: This study is a cross-sectional study of a diagnostic test. 78 children with sickle cell anemia between 2 to 16 years will be evaluated with both TCD and TCDI in order to determinate the TAMM with the two devices. Velocities obtained with both Doppler techniques will be compared using an intraclass correlation coefficient
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Preterm birth is a risk for normal brain development. Brain maturation that normally happens in the uterus is in very preterm infants a developmental challenge during their stay in a neonatal intensive care unit (NICU). Typical brain injuries of preterm infants include ischemic injuries, brain haemorrhages, ventricular dilatation (VD), and reduced brain volumes. Brain injury is a serious complication of prematurity leading to possible long term consequences for the neurodevelopment of the very low birth weight (VLBW) infant, such as cerebral palsy (CP), hearing impairments, vision problems, and delay in cognitive development.There is a need for further studies to ascertain the potential risk factors and their causal relationships to brain vulnerability, growth and development in the increasing number of surviving VLBW infants. This thesis consists of four studies evaluating the definitions, causes and consequences of brain lesions in VLBW(<1500g) or very low gestationalage (VLGA) (gestational age <32 gestational weeks) infants. We showed that the redistribution of fetal blood flow is a risk factor for smaller brain volumes at term. In addition,we showed that brain lesions related to prematurity are not associated with increased spontaneous crying behaviour or circadian rhythm development in infancy. However, the preterm infants began to fuss more often and were held more than term infants at five months of age. Furthermore, we showed that VD is associated with brain lesions and smaller brain volumes. Therefore, brain magneticresonance imaging can be recommended for infants with VD. VD together with other brain pathology is a risk factor for the onset of developmental impairments in VLBW/VLGA infants at two years of age.
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Intestinal complications after laparoscopic cholecystectomy are rare and usually caused by direct injury sustained on trocar insertion. However, intestinal ischaemia has been reported as an unusual complication of the pneumoperitoneum. We describe a 55-years-old patient who underwent an uneventful laparoscopic cholecystectomy after an episode of acute cholecystitis. Initial recovery was complicated by development of increasing abdominal pain which led to open laparotomy on day 2. Gangrene of the distal ileum and right-sided colon was detected and small bowel resection with right colectomy and primary anastomosis was performed. Histological examination of the resected ileum showed features of venous hemorragic infarction and trombosis. In view of the proximity of the operation it is assumed that ileal ischaemia was precipitated by carbon dioxide pneumoperitoneum. Some studies have been demonstrated that, within 30 minutes of establishing a pneumoperitoneum at an intraabdominal pressure of 16 mmHg, cardiac output, blood flow in the superior mesenteric artery and portal vein decrease progressively. Carbon dioxide pneumoperitoneum may lead to mechanical compression of the splanchnic veins and mesenteric vasoconstriction as a result of carbon dioxide absortion. The distribution of the ischaemic segment of intestine is also unusual as the most precarious blood supply is traditionally at the splenic flexure of the colon. It has been suggested that intermittent decompression of the abdomen reduces the risk of mesenteric ischaemia during penumoperitoneum especially in patients with predisposing clinical features for arteriosclerosis intestinal. In present patient was observed intestinal venous infarction what remains unclear but we think the carbon dioxide pneumoperitoneum have been related to it.
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A case of torsion of the gallbladder is presented. This is a rare condition that occurs when it is associated with anatomical variants related to abnormal fixation of the gallbladder to the liver bed. The blood irrigation is insufficient and the gallbladder develops necrosis. The abnormal implantation occurs in 4% of the population. If the gallbladder losses its fixations to the inferior margin of the liver with the presence of a 1011.g mesocyst a torsion can occur when this gallbladder twists axially with subsequent occlusion of the blood flow. The signs and symptoms are similar to those of severe acute cholecystitis: abrupt onset of the pain and large palpable mass below the right costal margin. The ultrasound can show a very large and anteriorly floating gallbladder: In this case, the ultrasound did not show any abnormal signs, so it is usually diagnosed at laparotomy and the treatement consists of cholecystectomy. This condition should be suspected in acute abdominal pain of unknown origin.