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21.
Cardio‐facio‐cutaneous syndrome (CFCS), a rare congenital disorder of RASopathies, displays high phenotypic variability. Complications during pregnancy and in the perinatal period are commonly reported. Polyhydramnios is observed in over half of pregnancies and might occur with fetal macrocephaly, macrosomia, and/or heart defects. Premature birth is not uncommon and any complications like respiratory insufficiency, edema, and feeding difficulties are present and might delay accurate clinical diagnosis. Besides neonatal complications, CFCS newborns and later infants have distinctive dysmorphic features usually accompanied by neurological (hypotonia with motor delay, neurocognitive delay) findings. Also, heart defects usually present at birth. Herein, we present the case of a female baby born prematurely from a pregnancy complicated with polyhydramnios, presenting at birth with craniofacial features typical for RASopathies, heart defects, neurological abnormalities, and hyperkeratosis unusual for a neonatal period. Due to the presence of a heart defect and other complications related to premature birth, the course of the disease was severe with a fatal outcome at the age of 9 months. The RASopathy, particularly CFCS, clinical diagnosis was confirmed and de novo p.Phe57Ile mutation in MAP2K2 was identified.  相似文献   
22.

PURPOSE

The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al2O3 and two Y-TZP core materials.

MATERIALS AND METHODS

Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data.

RESULTS

The characteristic strengths of Ce-TZP/Al2O3 specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05).

CONCLUSION

It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.  相似文献   
23.
Increased microvascular permeability resulting in tissue edema is a hallmark of sepsis-related microcirculatory failure, and leukocyte–endothelium interaction is thought to assume major importance in this context. However, the role of nitric oxide (NO) in the interplay of inflammation, leukocyte–endothelium interaction and increased microcirculatory permeability is still a matter of debate. Hollenberg et al. now report, in the previous issue of Critical Care, that neither genetic deletion nor pharmacologic blockade of the inducible isoform of the NO synthase (iNOS) affected the sepsis-related aggravation of leukocyte rolling and adhesion, whereas iNOS inhibition attenuated microvascular permeability. The authors conclude that excess NO resulting from iNOS activation is important in modulating vascular permeability during sepsis, but that this effect is independent of its action on leukocytes.  相似文献   
24.
25.
Objective To assess the effects of the potassium ATP (KATP) channel blocker HMR1402 (HMR) on systemic and hepato-splanchnic hemodynamics, oxygen exchange and metabolism during hyperdynamic porcine endotoxemia.Design Prospective, randomized, controlled study with repeated measures.Setting Animal laboratory.Subjects Eighteen pigs allocated to receive endotoxin alone (control group, CON, n=10) or endotoxin and HMR (6 mg/kg h–1, n=8).Interventions Anesthetized, mechanically ventilated, and instrumented pigs receiving continuous i.v. endotoxin were resuscitated with hetastarch to maintain mean arterial pressure (MAP) >60 mmHg. Twelve hours after starting the endotoxin infusion, they received HMR or its vehicle for another 12 h.Results HMR transiently increased MAP by about 15 mmHg, but this effect was only present during the first 1 h of infusion. The HMR decreased cardiac output due to a fall in heart rate, and thereby reduced liver blood flow. While liver O2 delivery and uptake remained unchanged, HMR induced hyperlactatemia [from 1.5 (1.1; 2.0), 1.4 (1.2; 1.8), and 1.2 (0.8; 2.0) to 3.1 (1.4; 3.2), 3.2 (1.6; 6.5), and 3.0 (1.0; 5.5) mmol/l in the arterial, portal and hepatic venous samples, respectively] and further increased arterial [from 8 (3; 13) to 23 (11; 57); p<0.05], portal [from 9 (4; 14) to 23 (14; 39); p<0.05] and hepatic vein [from 7 (0; 15) to 30 (8; 174), p<0.05] lactate/pyruvate ratios indicating impaired cytosolic redox state.Conclusion The short-term beneficial hemodynamic effects of KATP channel blockers have to be weighted with the detrimental effect on mitochondrial respiration.P. Asfar and Z. Iványi equally contributed to this work  相似文献   
26.
27.
OBJECTIVE: To investigate the systemic, pulmonary, and hepatosplanchnic hemodynamic and metabolic effects of delayed treatment with ethyl pyruvate in a long-term porcine model of hyperdynamic endotoxemia. DESIGN: Prospective, randomized, controlled experimental study with repeated measures. SETTING: Investigational animal laboratory. SUBJECTS: Anesthetized, mechanically ventilated, and instrumented pigs. INTERVENTIONS: After 12 hrs of continuous infusion of lipopolysaccharide and hydroxyethyl starch to keep mean arterial pressure >60 mm Hg, swine randomly received placebo (Ringer's solution; control group, n = 11) or ethyl pyruvate in lactated Ringer's solution (n = 8; 0.03 g.kg(-1) loading dose over 10 mins, thereafter 0.03 g.kg(-1)hr(-1) for 12 hrs). MEASUREMENTS AND MAIN RESULTS: Whereas mean arterial pressure significantly decreased in control animals, mean arterial pressure was maintained at the baseline level in pigs treated with ethyl pyruvate. Global oxygen uptake was comparable, so that the trend toward a higher oxygen transport and the significantly higher mixed venous hemoglobin oxygen saturation resulted in a significantly lower oxygen extraction in the ethyl pyruvate group. Ethyl pyruvate reduced intrapulmonary venous admixture and resulted in significantly greater Pa(O2)/F(IO2) ratios. Despite comparable urine production in the two groups during the first 18 hrs of endotoxemia, ethyl pyruvate significantly increased diuresis during the last 6 hrs of the study. Lipopolysaccharide-induced systemic and regional venous metabolic acidosis was significantly ameliorated by ethyl pyruvate. Endotoxemia increased both blood nitrate + nitrite and isoprostane concentrations, and ethyl pyruvate attenuated the response of these markers of nitric oxide production and lipid peroxidation. CONCLUSIONS: Ethyl pyruvate infusion resulted in improved hemodynamic stability and ameliorated acid-base derangements induced by chronic endotoxemia in pigs. Reduced oxidative stress and an decreased nitric oxide release probably contributed to these effects.  相似文献   
28.
This study is a case report of a meningomyelocele patient with congenital kyphosis who was treated with kyphectomy and a special approach to soft tissue healing. The objective of this study is to show a step by step approach to surgical treatment and postoperative care of a meningomyelocele patient with congenital kyphosis. In meningomyelocele the incidence of kyphosis is around 12-20%. It may cause recurrent skin ulcerations, impaired sitting balance and respiratory compromise. Kyphectomy has first been described by Sharrard. This surgery is prone to complications including pseudoarthrosis, skin healing problems, recurrence of deformity and deep infections. A 15-year-old male presented with congenital kyphosis due to meningomyelocele. He had back pain, deformity and bedsores at the apex of the deformity. The wound cultures showed Staphylococcus epidermidis colonisation at the apex. He was given appropriate antibiotic prophylaxis. During surgery, the apex of the deformity was exposed through a spindle-shaped incision. After instrumentation and excision of the apex, correction was carried out by cantilever technique. Two screws were inserted to the bodies of L3 and T11. After the operation, the skin was closed in a reverse cross fashion. He was sent to hyperbaric oxygen treatment for prevention of a subsequent skin infection and for rapid healing of skin flaps post operation. The patient's deformity was corrected from a preoperative Cobb angle of 135°-15° postoperative. The skin healed without any problems. Preoperative culture and appropriate antibiotic prophylaxis, spindle-shaped incision, reverse cross-skin closure and postoperative hyperbaric oxygen treatment can be useful adjuncts to treatment in congenital kyphosis patients with myelomeningocele to prevent postoperative wound healing and infection problems. Reduction screws and intracorporeal compression screws help to reduce the amount of screws and aid in corection of the deformity.  相似文献   
29.
Ultrasonically guided percutaneous biopsy of peripheral pulmonary masses.   总被引:3,自引:0,他引:3  
Ultrasonically guided percutaneous biopsy and aspiration of solid and cystic structures in the abdomen, neck, and pericardial space are common practice. The technique may be utilized for biopsy of peripheral pulmonary masses in contact with the chest wall, in order to assure accurate placement of the needle in the center of the mass, reduce the risk of pneumothorax, and eliminate the exposure to radiation that occurs with fluoroscopic guidance. Four patients had successful biopsies in this manner, without complications. Histologic studies revelaed malignant neoplasms in three and lipoid pneumonia in one.  相似文献   
30.
Objectives. The Val158-allele of the catechol-O-methyltransferase (COMT) Val158Met (rs4680) functional polymorphism has been identified as a risk factor for antisocial behaviour in attention-deficit/hyperactivity disorder (ADHD). Here, we used voxel-based morphometry to investigate the effects of Val158Met polymorphism on grey matter (GM) volumes in a sample of 7–13-year-old children. Methods. MRI and genotype data were obtained for 38 children with combined-type ADHD and 24 typically developing (TD) children. Four regions of interest were identified: striatum, cerebellum, temporal lobe and inferior frontal gyrus (IFG). Results. When compared to TD children, those with ADHD had a significant decrease of GM volume in the IFG. Volume in this region was negatively correlated with ratings of hyperactivity/impulsivity symptoms. Furthermore, the smaller GM volume in the IFG was attributed to the presence of the Met158-allele, as only children with ADHD carrying a Met158-allele exhibited such decrease in the IFG. Children with ADHD homozygotes for the Val158-allele presented increased GM volume in the caudate nucleus when compared with TD children. Conclusions. This study provides the first evidence of a modulation of ADHD-related GM volume alterations by Val158Met in two key regions, possibly mediating the relationship between Val158Met polymorphism and antisocial behaviour in children with ADHD.  相似文献   
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