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11.
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
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An infant girl with elevated blood lactate, pyruvate, and plasma branched-chain amino acids was diagnosed with dihydrolipoamide dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4) deficiency. Activities of the pyruvate dehydrogenase complex and E3 from patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in cultured skin fibroblasts, respectively. Western blot analysis demonstrated that the amount of E3 protein in fibroblasts from the patient and her father was about half of controls, while Northern blot analysis showed normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs from the patient revealed two mutations in separate alleles. One is a single base insertion of an extra adenine in the last codon of the leader peptide sequence (TAC-->TAAC) leading to a nonsense mutation which results in the premature termination of the precursor E3 polypeptide (Y35X). The other is a missense mutation due to substitution of guanine for adenine, causing an Arg-->Gly substitution at amino acid 460 of the mature protein (R460G) which triggers the loss of E3 activity probably by structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the parents demonstrated that the nonsense mutation was inherited from the father and the missense mutation was inherited from the mother.   相似文献   
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A study of the performance of the first Wyndham Scheme students in the Faculty of Medicine at the University of New South Wales was undertaken. Forty-five percent of the cohort of 237 graduated in the minimum time, and 76% eventually graduated in succeeding years. Of the 130 entrants with Higher School Certificate (HSC) aggregates of 500+, 60% graduated in minimum time; in the case of the 107 entrants with HSC aggregates of less than 500, the figure was 28%. There was an extremely high correlation rate (r = 0.98) between HSC aggregate and success in the course at the first attempt. There was no significant difference between the minimum time or eventual graduation rates of males (211) and females (26), despite the fact that females had a significantly higher performance in the HSC; There was no improvement in the numbers graduating in the minimum time compared with the first intake of medical students at the University of New South Wales, or the last "pre-Wyndham" intake. A comment about wastage rates is made and suggestions for remedying the situation are put forth.  相似文献   
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OBJECTIVE: The authors assessed selective basal ganglia involvement in a subgroup of children with obsessive-compulsive disorder (OCD) and/or tics believed to be associated with streptococcal infection. METHOD: Using computer-assisted morphometric techniques, they analyzed the cerebral magnetic resonance images of 34 children with presumed streptococcus-associated OCD and/or tics and 82 healthy comparison children who were matched for age and sex. RESULTS: The average sizes of the caudate, putamen, and globus pallidus, but not of the thalamus or total cerebrum, were significantly greater in the group of children with streptococcus-associated OCD and/or tics than in the healthy children. The differences were similar to those found previously for subjects with Sydenham's chorea compared with normal subjects. CONCLUSIONS: These results support the hypothesis that there is a distinct subgroup of subjects with OCD and/or tics who have enlarged basal ganglia. These findings are consistent with the hypothesis of an autoimmune response to streptococcal infection.  相似文献   
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Objective

To establish the local incidence of hearing loss in newborns with Hypoxic Ischaemic Encephalopathy (HIE) and to identify associated risk factors.

Study design

Retrospective Cohort Study. Neonatal Intensive Care Unit (NICU) dual stage hearing screening protocol, including automated otoacoustic emissions (AOAE) and automated auditory brainstem response (AABR) testing.

Results

57 newborns received therapeutic hypothermia for HIE. Twelve babies (21%) died. Audiology data was incomplete in 3 babies. Complete data was available for 42 babies (male n = 24), 4 (9.5%) of whom had hearing impairment. The development of hearing loss was associated with abnormal blood glucose levels (p = 0.006), low Apgar score at 1 min (p = 0.0219) and evidence of multi organ dysfunction [high creatinine (p = 0.0172 and 0.0198) and raised liver transaminases (aspartate aminotransferase (AST) p = 0.0012, alanine aminotransferase (ALT) p = 0.0037)]. An association with gentamicin was not found.

Conclusion

This study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE. Blood glucose should be monitored carefully in these infants and developmental surveillance should include formal audiology. Further larger studies are needed to clarify the role, if any, of hypothermia per se in causation of hearing loss and to fully identify risk factors for hearing impairment in this population.

What is new

The current study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE.No association between gentamicin use and the development of hearing impairment was found however initial blood glucose outside the normal range was of significance.Other factors associated with hearing impairment were low Apgar scores, greater need for resuscitation and evidence of multi organ dysfunction (renal and liver failure).  相似文献   
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Bacterial meningitis in infants: sonographic findings   总被引:1,自引:0,他引:1  
Han  BK; Babcock  DS; McAdams  L 《Radiology》1985,154(3):645-650
A retrospective study was performed on 78 patients (newborn to 2 years old) with clinically proved bacterial meningitis. Sonograms were obtained during the acute illness and medical records were reviewed. The spectrum of sonographic features of meningitis included normal scans (30 patients), ventriculomegaly (11 patients), echogenic sulci (31 patients), extra-axial fluid collections (26 patients), abnormal parenchymal echogenicity (9 patients), evidence of ventriculitis (5 patients), and brain abscess (1 patient). In 46 patients, correlation between the sonographic findings and neurologic outcome on clinical follow-up (6 months to 4 years) was made. Findings of abnormal parenchymal echogenicity and/or moderate-to-marked ventriculomegaly were associated with significant neurologic sequelae; however, echogenic sulci and small extra-axial fluid collections did not appear to have any prognostic significance. Twenty-nine of the 78 patients had sonography without clinical indication of complications of meningitis, and in no patient was a significant abnormality found. Our study suggests that sonography is indicated only when there is clinical suspicion of complications.  相似文献   
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