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991.
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Introduction: This article describes changes in regional cerebral perfusion and brain metabolism in a case of bacterial meningitis complicating
severe traumatic brain injury.
Case report: As part of clinical monitoring of patients with severe head injury, cerebral microdialysis was performed and extracellular
concentration of glucose, lactate, glutamate, and pyruvate was determined. A thermal diffusion probe was used for bedside
monitoring of cerebral blood flow. A cinetobacter meningitis complicated the clinical course on the seventh post-admission
day and dramatically altered the neurochemistry. Microdialy sate analysis showed glucose under the detection limit, lactate
at moderately high levels, and a marked increase in glutamate and pyruvate levels. A reduction of cerebral perfusion was detected
in the early phase of meningitis, probably secondary to vascular complications related to the inflammatory process.
Discussion: This case describes an emerging area of study and practice in patients with brain injury. It demonstrates how cerebral perfusion
monitoring and study of brain metabolism can provide an early detection of secondary events that complicate severe head injury
and can contribute to a better understanding of the complex pathogenetic mechanisms responsible for neuronal damage. 相似文献
994.
Scmidt-Sidor B Szymańska K Lewandowska E Mierzewska H Wierzba-Bobrowicz T Pasennik E Stepień T 《Folia neuropathologica / Association of Polish Neuropathologists and Medical Research Centre, Polish Academy of Sciences》2005,43(3):186-190
We retrospectively analyzed a case of a 7-month-old infant with a delay of psychomotor development, slow pupillary light reflexes, horizontal nystagmus, spasticity and bilateral optic nerve atrophy. At the end of life there were problems with swallowing. Ventriculography showed widening of the lateral ventricles and atrophy in the frontal lobes. EEG revealed generalized changes. Clinically, leucodystrophy was diagnosed. General autopsy revealed cardiac hypertrophy. Neuropathological picture showed orthochromatic leucodystrophy with some features characteristic of neuropathology of mitochondrial disease: capillary hyperplasia and hypertrophy, spongiosis and symmetrical, bilateral damage of brain stem structures. The last one is characteristic of Leigh syndrome. Electron microscopic evaluation showed abnormal mitochondria, myelin and neurofibrils destruction. Hypertrophy of the heart may be also connected with mitochondrial disease. 相似文献
995.
Perez-Cerda C García-Villoria J Ofman R Sala PR Merinero B Ramos J García-Silva MT Beseler B Dalmau J Wanders RJ Ugarte M Ribes A 《Pediatric research》2005,58(3):488-491
We describe three patients, from two Spanish families, with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase (MHBD) deficiency, a recently described X-linked neurodegenerative inborn error of isoleucine metabolism. Two of them are males with severe lactic acidosis suggestive of a mitochondrial encephalopathy, and the third is a female who was less severely affected, suggesting skewed X-inactivation. Molecular studies revealed a new missense mutation, 740A-->G, in one family and a previously described mutation, 388C-->T, in the other, causing the amino acid substitutions N247S and R130C, respectively. Both male patients died, one of them despite treatment with an isoleucine-restricted diet, but the disease has remained stable in the female patient after 1 y of treatment. 相似文献
996.
997.
Simonini G Masi L Giani T Piscitelli E Cimaz R Vierucci S Brandi ML Falcini F 《The Journal of rheumatology》2005,32(11):2233-2238
OBJECTIVE: Emerging evidence from in vitro studies and mouse genetics attributes to osteoprotegerin (OPG), a member of the tumor necrosis factor receptor family, an important role in vascular biology. We evaluated serum levels of OPG in a group of children with Kawasaki disease (KD), before immunoglobulin (IVIG) infusion and at 3-month followup. METHODS: Fifty patients (38 boys, 20 girls, median age 3.6 yrs, range 4 mo-7.4 yrs) fulfilling criteria for the diagnosis of KD, 30 febrile controls with infectious diseases, 18 patients with juvenile systemic lupus erythematosus (JSLE), and 40 healthy controls were enrolled. All KD patients received IVIG treatment within the first 10 days of illness, and aspirin. Coronary artery abnormalities (CAA) were reported in 6 out of 58 patients; all were male and younger than 5 years. Serum OPG was measured by ELISA in patients with KD before IVIG and at 3-month followup (median time 3.2 mo, range 3-3.5). RESULTS: At baseline and at the 3-month followup, KD patients had significantly higher OPG serum levels than febrile controls (p < 0.001 and p < 0.004, respectively), JSLE patients (p < 0.0001), and healthy controls (p < 0.0001). At baseline, KD patients who developed CAA had higher OPG serum levels than those without CAA (p = 0.0001); this difference was not present at 3-month followup. The optimal OPG cutoff value of 123.2 pg/ml was a significant predictor for CAA, with a sensitivity of 100% (6/6), a specificity of 96% (50/52), and a positive predictive value of 75% (6/8). CONCLUSION: High OPG levels might be the result of compensatory production during acute and subacute phases of KD. OPG assay might be an additional clinically useful marker to monitor and differentiate patients who develop, from those who do not develop, such coronary artery abnormalities. 相似文献
998.
Correlation between right ventricular indices and clinical improvement in epoprostenol treated pulmonary hypertension patients 总被引:1,自引:0,他引:1
Nath J Demarco T Hourigan L Heidenreich PA Foster E 《Echocardiography (Mount Kisco, N.Y.)》2005,22(5):374-379
The aim of this study was to evaluate which parameter of right ventricular (RV) echocardiographic best mirrors the clinical status of patients with pulmonary arterial hypertension. Patients with pulmonary arterial hypertension on epoprostenol therapy were identified via hospital registry. Twenty patients, (16 females, 4 males) were included in the study, 9 with primary pulmonary hypertension and 11 with other diseases. Echocardiograms before therapy and at 22.7 (+/-9.3) months into therapy were compared. The right ventricular myocardial performance index (RVMPI) was measured as the sum of the isometric contraction time and the isometric relaxation time divided by right ventricular ejection time. Other measures included peak tricuspid regurgitation jet velocity (TRV), pulmonary artery systolic pressure (PASP), pulmonary valve velocity time integral (PVVTI), PASP/PVVTI (as an index of total pulmonary resistance) and symptoms by New York Heart Association (NYHA) functional class. Echo parameters of right ventricular function were analyzed in patients, before and during therapy. There was significant improvement of NYHA class in patients following epoprostenol therapy (P < 0.0001). Peak tricuspid regurgitant jet velocity (pre 4.2 +/- 0.6 m/sec, post 3.8 +/- 0.7 m/sec, P = 0.02) and PASP/PVVTI (pre 6.7 +/- 3.3 mmHg/m per second, post 4.8 +/- 2.2 mmHg/m per second, P < 0.0001) were significantly improved during treatment. RVMPI did not improve (pre 0.6 +/- 0.3, post 0.6 +/- 0.3, P = 0.54). Changes in NYHA class did not correlate with changes in RVMPI (P = 0.33) or changes in PASP/PVVTI (P = 0.58). Despite significant improvements in TRV, PASP/PVVTI, and NYHA class, there was no significant change in RVMPI on epoprostenol therapy. Changes in right ventricular indices were not correlated with changes in NYHA class. 相似文献
999.
Systematic yeast synthetic lethal and synthetic dosage lethal screens identify genes required for chromosome segregation 下载免费PDF全文
1000.
Farroni T Johnson MH Menon E Zulian L Faraguna D Csibra G 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(47):17245-17250
There is currently no agreement as to how specific or general are the mechanisms underlying newborns' face preferences. We address this issue by manipulating the contrast polarity of schematic and naturalistic face-related images and assessing the preferences of newborns. We find that for both schematic and naturalistic face images, the contrast polarity is important. Newborns did not show a preference for an upright face-related image unless it was composed of darker areas around the eyes and mouth. This result is consistent with either sensitivity to the shadowed areas of a face with overhead (natural) illumination and/or to the detection of eye contact. 相似文献