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41.
42.
Galloway-Mowat syndrome (GMS) is a rare autosomal recessive disorder characterized by early onset nephrotic syndrome and microcephaly with various anomalies of the central nervous system. GMS likely represents a heterogeneous group of disorders with hitherto unknown genetic etiology. The clinical phenotype to some extent overlaps that of Pierson syndrome (PS), which comprises congenital nephrotic syndrome and distinct ocular abnormalities but which may also include neurodevelopmental deficits and microcephaly. PS is caused by mutations of LAMB2, the gene encoding laminin beta2. We hypothesized that GMS might be allelic to PS or be caused by defects in proteins that interact with laminin beta2. In a cohort of 18 patients with GMS or a GMS-like phenotype we therefore analyzed the genes encoding laminin beta2 (LAMB2), laminin alpha5 (LAMA5), alpha3-integrin (ITGA3), beta1-integrin (ITGB1) and alpha-actinin-4 (ACTN4), but we failed to find causative mutations in these genes. We inferred that LAMA5, ITGA3, ITGB1, and ACTN4 are not directly involved in the pathogenesis of GMS. We excluded LAMB2 as a candidate gene for GMS. Further studies are required, including linkage analysis in families with GMS to identify genes underlying this disease.  相似文献   
43.
OBJECT: The use of dural grafts is frequently unavoidable when tension-free dural closure cannot be achieved following neurosurgical procedures or trauma. Biodegradable collagen matrices serve as a scaffold for the regrowth of natural tissue and require no suturing. The aim of this study was to investigate the efficacy and safety of dural repair with a collagen matrix using different fixation techniques. METHODS: A total of 221 patients (98 male and 123 female; mean age 55.6 +/- 17.8 years) undergoing cranial (86.4%) or spinal (13.6%) procedures with the use of a collagen matrix dural graft were included in this retrospective study. The indications for use, fixation techniques, and associated complications were recorded. RESULTS: There were no complications of the dural graft in spinal use. Five (2.6%) of 191 patients undergoing cranial procedures developed infections, 3 of which (1.6%) were deep infections requiring surgical revision. There was no statistically significant relationship between the operative field status before surgery and the occurrence of a postoperative wound infection (p = 0.684). In the 191 patients undergoing a cranial procedure, cerebrospinal fluid (CSF) collection occurred in 5 patients (2.6%) and a CSF fistula in 5 (2.6%), 3 of whom (1.6%) required surgical revision. No patient who underwent an operation with preexisting CSF leakage had postoperative CSF leakage. Postoperative infection significantly increased the risk for postoperative CSF leakage. The collagen matrix was used without additional fixation in 124 patients (56.1%), with single fixation in 55 (24.9%), and with multiple fixations in 42 (19%). There were no systemic allergic reactions or local skin changes. Follow-up imaging in 112 patients (50.7%) revealed no evidence of any adverse reaction to the collagen graft. CONCLUSIONS: The collagen matrix is an effective and safe cranial and spinal dural substitute that can be used even in cases of an existing local infection. Postoperative deep infection increases the risk for CSF leakage.  相似文献   
44.
PURPOSE: The aim of this study was to determine the optimal amount of contrast agent for helical CT of the trunk during primary radiologic evaluation of polytraumatized patients. METHOD: Eighty-three patients with severe and multiple injuries (mean age 36.2 years) underwent standardized helical CT examination with administration of a single contrast agent bolus of iohexol (Accupaque 300) at volumes of 120, 150, and 180 ml. Image quality was estimated by two blinded radiologists using a visual analogue scale. Analysis further included density measurements in regions of interest (ROIs) placed in the ascending, descending, and abdominal aorta as well as in the liver and spleen. RESULTS: The qualitative rating of the contrast agent effect after administration of 150 and 180 ml was significantly better compared with 120 ml [odds ratio (OR) 12.05, 95% confidence interval (CI) 3.50-41.52 and OR 12.14, 95% CI 3.36-43.85, respectively]. A dose increase from 120 to 150 ml resulted in a significantly better enhancement of the abdominal aorta (p = 0.006). The highest dose of 180 ml was not associated with a diagnostic gain in the other ROIs. CONCLUSION: We recommend administration of 150 ml of iohexol as the optimal amount of contrast material for single phase bolus administration in emergency helical CT examination of the chest and abdomen.  相似文献   
45.
46.
There appear to be contradicting theories and empirical findings on the association between adolescent Social Anxiety Disorder (SAD) symptoms and cannabis use, suggesting potential risk as well as protective pathways. The aim of this six-year longitudinal study was to further examine associations between SAD symptoms and cannabis use over time in adolescents from the general population, specifically focusing on the potential role that adolescents’ involvement with their peers may have in these associations. Participants were 497 Dutch adolescents (57 % boys; M age = 13.03 at T1), who completed annual self-report questionnaires for 6 successive years. Cross-lagged panel analysis suggested that adolescent SAD symptoms were associated with less peer involvement 1 year later. Less adolescent peer involvement was in turn associated with lower probabilities of cannabis use as well as lower frequency of cannabis use 1 year later. Most importantly, results suggested significant longitudinal indirect paths from adolescent SAD symptoms to cannabis use via adolescents’ peer involvement. Overall, these results provide support for a protective function of SAD symptoms in association with cannabis use in adolescents from the general population. This association is partially explained by less peer involvement (suggesting increased social isolation) for those adolescents with higher levels of SAD symptoms. Future research should aim to gain more insight into the exact nature of the relationship between anxiety and cannabis use in adolescents from the general population, especially regarding potential risk and protective processes that may explain this relationship.  相似文献   
47.

Purpose  

Numerous posterior non-fusion systems have been developed within the past decade to resolve the disadvantages of rigid instrumentations and preserve spinal motion. The aim of this study was to investigate the effect of a new dynamic stabilization device, to measure the screw anchorage after flexibility testing and compare it with data reported in the literature.  相似文献   
48.
Upper abdominal pain, a frequent symptom of the presence of gallstone disease, is the cause of 6% of the emergency calls of the Austrian emergency system. Pain resulting from cholelithiasis is characteristically severe. Recent data show that active warming during emergency transport of trauma victims is effective in reducing pain. Therefore, we hypothesized that local active warming of the abdomen would be an effective pain treatment for patients with acute cholelithiasis and could be provided by paramedics. Sixty patients (>19 yr) consented to participate in this study. They were divided into two groups: Group 1, who received active warming of the upper abdomen with a carbon-fiber warming blanket (42 degrees C), and Group 2, who received no warming of the abdomen. Neither group received any drug-based pain care. Patients were asked to rate their pain and anxiety by using visual analog scales (VAS). Statistical evaluation was performed with Student's t-test; P < 0.05 was considered significant. In Group 1, a significant (P < 0.01) pain reduction was recorded in all cases on a visual analog scale (VAS), from 86.8 +/- 5.5 mm to 41.2 +/- 16.2 mm. In Group 2, the patients' pain scores remained comparable, from 88.3 +/- 9.9 mm to 88.1 +/- 10.0 mm on a VAS. In comparing Group 1 with Group 2 on arrival at the hospital, pain scores showed a significant difference (P < 0.01). In Group 1, the VAS score changes for anxiety were significantly reduced (P < 0.01), from 82.7 +/- 10.8 mm before treatment to 39.0 +/- 14.0 mm after treatment. In Group 2, a nonsignificant change of this score was noted, from 84.5 +/- 14.6 mm to 83.5 +/- 8.4 mm. Comparing Group 1 with Group 2 on arrival at the hospital showed a significant difference in anxiety scores (P < 0.01). We conclude that local active warming is an effective and easy-to-learn treatment for pain resulting from acute cholelithiasis in emergency care. IMPLICATIONS: Active local warming of the upper abdomen is an effective treatment for patients with cholelithiasis being transported to the hospital by paramedics who are not permitted to provide any drug-based pain care. We observed no negative side effects of this treatment.  相似文献   
49.
Human congenital anomalies of the kidney and urinary tract (CAKUT) represent the major causes of chronic renal failure (CRF) in children. This set of disorders comprises renal agenesis, hypoplasia, dysplastic or double kidneys, and/or malformations of the ureter. It has recently been shown that mutations in several genes, among them BMP4, are associated with hereditary renal developmental diseases. In BMP4, we formerly identified three missense mutations (S91C, T116S, N150K) in five pediatric CAKUT patients. These BMP4 mutations were subsequently studied in a cellular expression system, and here we present functional data demonstrating a lower level of messenger RNA (mRNA) abundance in Bmp4 mutants that indicates a possible negative feedback of the mutants on their own mRNA expression and/or stability. Furthermore, we describe the formation of alternative protein complexes induced by the S91C-BMP4 mutation, which results in perinuclear endoplasmic reticulum (ER) accumulation and enhanced lysosomal degradation of Bmp4. This work further supports the role of mutations in BMP4 for abnormalities of human kidney development.  相似文献   
50.
A 7-month-old male infant was referred for investigation after a documented febrile urinary tract infection. His past medical history was characterized by episodes of unexplained fever and mild dehydration. The ultrasound examination of his kidneys demonstrated bilateral diffuse medullary nephrocalcinosis. His serum and urine biochemistry revealed hypomagnesemia (0.4 mmol/l), hyperuricaemia (506 µmol/l), mildly increased iPTH (71 pg/ml) and hypercalciuria (16.0 mg/kg/day). The diagnosis of familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) was confirmed by mutational analysis of the CLDN16 gene, encoding paracellin-1. Sequencing displayed a homozygous Leu151Phe exchange affecting the first extracellular loop of paracellin-1. There were eight family relatives who underwent biochemical analysis, renal ultrasound and genetic investigation for CLDN16 mutations. Five of them were found to be heterozygous for the Leu151Phe mutation. Two heterozygotes (the mother and the maternal grandfather) presented with hypercalciuria. The grandfather had a history of recurrent passage of calculi. These findings point to the role of heterozygous CLDN16 gene mutations in renal pathophysiology. In conclusion, patients suspected of having FHHNC should be screened for CLDN16 mutations, especially with respect to genetic counseling. In addition, heterozygotes at risk should be clinically assessed in order to prevent renal complications of hypercalciuria.  相似文献   
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