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21.
Shaoyi Chen Coleen M Atkins Chunli L Liu Ofelia F Alonso W Dalton Dietrich Bingren R Hu 《Journal of cerebral blood flow and metabolism》2007,27(5):939-949
In response to traumatic brain injury (TBI), neurons initiate neuroplastic processes through the activation of intracellular signaling pathways. However, the molecular mechanisms underlying neuroplasticity after TBI are poorly understood. To study this, we utilized the fluid-percussion brain injury (FPI) model to investigate alterations in the mammalian target of rapamycin (mTOR) signaling pathways in response to TBI. Mammalian target of rapamycin stimulates mRNA translation through phosphorylation of eukaryotic initiation factor 4E binding protein-1 (4E-BP1), p70 ribosomal S6 kinase (p70S6K), and ribosomal protein S6 (rpS6). These pathways coordinate cell growth and neuroplasticity via dendritic protein synthesis. Rats received sham surgery or moderate parasagittal FPI on the right side of the parietal cortex, followed by 15 mins, 30 mins, 4 h, 24 h, or 72 h of recovery. Using Western blot analysis, we found that mTOR, p70S6K, rpS6, and 4E-BP1 phosphorylation levels were significantly increased in the ipsilateral parietal cortex and hippocampus from 30 mins to 24 h after TBI, whereas total protein levels were unchanged. Using confocal microscopy to localize these changes, we found that rpS6 phosphorylation was increased in the parietal cortex and all subregions of the hippocampus. In accordance with these results, eIF4E, a key, rate-limiting mRNA translation factor, was also phosphorylated by mitogen-activated protein kinase-interacting kinase 1 (Mnk1) 15 mins after TBI. Together, these results suggest that changes in mRNA translation may be one mechanism that neurons use to respond to trauma and may contribute to the neuroplastic changes observed after TBI. 相似文献
22.
F. Rensch B. Harder M. Goebeler W. Back J.B. Jonas Dr. F. Schlichtenbrede 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2009,106(8):735-739
Brooke’s syndrome is a rare autosomal dominant dermatosis characterized by multiple trichoepitheliomas, which preferentially arise in the face. Therapy consists of excisional surgery of larger tumors and for multiple lesions, dermal abrasion or laser therapy may be considered. Patients with Brooke’s syndrome should be closely followed-up due to the possible development of malignant skin tumours. Here, we present a patient with Brooke’s syndrome and report on the course of treatment. 相似文献
23.
Effect of early and late antibiotic treatment in experimental acute pancreatitis in rats 总被引:1,自引:0,他引:1
Michael Schwarz Bertram Poch Rainer Isenmann Dietrich Kriese Eva Rozdzinski Hans G. Beger Frank Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(3):365-370
Background The clinical course in acute necrotizing pancreatitis is mainly determined by bacterial infection of pancreatic and peripancreatic
necrosis. The effect of two antibiotic regimens for early and late treatment was investigated in the taurocholate model of
necrotizing pancreatitis in the rat.
Materials and methods Seventy male Wistar rats were divided into five pancreatitis groups (12 animals each) and a sham-operated group (10 animals).
Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals received two different
antibiotic regimes (20 mg/kg imipenem or 20 mg/kg ciprofloxacin plus 20 mg/kg metronidazole) early at 2, 12, 20, and 28 h
after induction of pancreatitis or late at 16 and 24 h after induction of pancreatitis or no antibiotics (control). Animals
were examined after 30 h for pancreatic and extrapancreatic infection.
Results Early and late antibiotic treatment with both regimes could significantly reduce pancreatic infection from 58 to 8–25%. However,
extrapancreatic infection was only reduced by early antibiotic therapy. While quinolones also reduced bacterial counts in
small and large bowel, imipenem did not.
Conclusions In our animal model of necrotizing pancreatitis, early and late treatment with ciprofloxacin/metronidazole and imipenem reduce
bacterial infection of the pancreas. Extrapancreatic infection, however, is reduced significantly only by early antibiotic
treatment. The effectivity of early antibiotic treatment in the clinical setting should be subject to further investigation
with improved study design and sufficient patient numbers. 相似文献
24.
25.
Van Buskirk Glenn A. González Mario A. Shah Vinod P. Barnhardt Scott Barrett Colin Berge Stephen Cleary Gary Chan Keith Flynn Gordon Foster Thomas Gale Robert Garrison Raymond Gochnour Scott Gotto Amanda Govil Sharad Gray Vivian A. Hammar James Harder Samuel Hoiberg Charles Hussain Ajaz Karp Carol Llanos Hector Mantelle Juan Noonan Patrick Swanson David Zerbe Horst 《Pharmaceutical research》1997,14(7):848-852
Pharmaceutical Research - 相似文献
26.
27.
Emine Sözeri Dietrich Feist Hans Ruder Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(3):307-311
Renal lesions have repeatedly been described in Wilson’s disease (WD). We investigated the excretion of total protein, albumin,
low (LMW) and high molecular weight (HMW) proteins, N-acetyl-β-D-glucosaminidase (NAG), and calcium, as well as creatinine clearance, in 24-h urine samples of 41 patients with WD aged 6 – 37
(mean 17) years who had been treated for a period of 0 – 15 (mean 4.5) years with D-penicillamine (900 mg/day). The amount of all protein excreted was significantly increased compared with controls, 39% of
patients presenting with total proteinuria more than two standard deviations from the mean of controls. The changes in protein
excretion depended on the duration of treatment. LMW proteinuria was elevated almost exclusively in the first 2 years after
the start of treatment, indicating early tubular damage. This is supported by an initially high excretion of β2-microglobulin, NAG, and calcium. Increased excretion of HMW proteins, including albumin, persisted over longer periods, which
suggests glomerular injury in some patients, possibly related to the use of D-penicillamine. Creatinine clearance remained roughly within normal limits. We propose that renal function should regularly
be checked in patients with WD.
Received October 26, 1995; received in revised form August 27, 1996; accepted September 20, 1996 相似文献
28.
Intrapericardial teratoma. Ultrasonic and pathological features 总被引:1,自引:0,他引:1
29.
Udaya DeSilva Laura Elnitski Jacquelyn R Idol Johannah L Doyle Weiniu Gan James W Thomas Scott Schwartz Nicole L Dietrich Stephen M Beckstrom-Sternberg Jennifer C McDowell Robert W Blakesley Gerard G Bouffard Pamela J Thomas Jeffrey W Touchman Webb Miller Eric D Green 《Genome research》2002,12(1):3-15
Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder. 相似文献
30.
Gillingham MB Connor WE Matern D Rinaldo P Burlingame T Meeuws K Harding CO 《Molecular genetics and metabolism》2003,79(2):114-123
Current dietary therapy for long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) or trifunctional protein (TFP) deficiency consists of fasting avoidance, and limiting long-chain fatty acid (LCFA) intake. This study reports the relationship of dietary intake and metabolic control as measured by plasma acylcarnitine and organic acid profiles in 10 children with LCHAD or TFP deficiency followed for 1 year. Subjects consumed an average of 11% of caloric intake as dietary LCFA, 11% as MCT, 12% as protein, and 66% as carbohydrate. Plasma levels of hydroxypalmitoleic acid, hydroxyoleic, and hydroxylinoleic carnitine esters positively correlated with total LCFA intake and negatively correlated with MCT intake suggesting that as dietary intake of LCFA decreases and MCT intake increases, there is a corresponding decrease in plasma hydroxyacylcarnitines. There was no correlation between plasma acylcarnitines and level of carnitine supplementation. Dietary intake of fat-soluble vitamins E and K was deficient. Dietary intake and plasma levels of essential fatty acids, linoleic and linolenic acid, were deficient. On this dietary regimen, the majority of subjects were healthy with no episodes of metabolic decompensation. Our data suggest that an LCHAD or TFP-deficient patient should adhere to a diet providing age-appropriate protein and limited LCFA intake (10% of total energy) while providing 10-20% of energy as MCT and a daily multi-vitamin and mineral (MVM) supplement that includes all of the fat-soluble vitamins. The diet should be supplemented with vegetable oils as part of the 10% total LCFA intake to provide essential fatty acids. 相似文献