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101.
Holly L Rosenzweig Manabu Minami Nikola S Lessov Sarah C Coste Susan L Stevens David C Henshall Robert Meller Roger P Simon Mary P Stenzel-Poore 《Journal of cerebral blood flow and metabolism》2007,27(10):1663-1674
Lipopolysaccharide (LPS) preconditioning provides neuroprotection against subsequent cerebral ischemic injury. Tumor necrosis factor-alpha (TNFalpha) is protective in LPS-induced preconditioning yet exacerbates neuronal injury in ischemia. Here, we define dual roles of TNFalpha in LPS-induced ischemic tolerance in a murine model of stroke and in primary neuronal cultures in vitro, and show that the cytotoxic effects of TNFalpha are attenuated by LPS preconditioning. We show that LPS preconditioning significantly increases circulating levels of TNFalpha before middle cerebral artery occlusion in mice and show that TNFalpha is required to establish subsequent neuroprotection against ischemia, as mice lacking TNFalpha are not protected from ischemic injury by LPS preconditioning. After stroke, LPS preconditioned mice have a significant reduction in the levels of TNFalpha (approximately threefold) and the proximal TNFalpha signaling molecules, neuronal TNF-receptor 1 (TNFR1), and TNFR-associated death domain (TRADD). Soluble TNFR1 (s-TNFR1) levels were significantly increased after stroke in LPS-preconditioned mice (approximately 2.5-fold), which may neutralize the effect of TNFalpha and reduce TNFalpha-mediated injury in ischemia. Importantly, LPS-preconditioned mice show marked resistance to brain injury caused by intracerebral administration of exogenous TNFalpha after stroke. We establish an in vitro model of LPS preconditioning in primary cortical neuronal cultures and show that LPS preconditioning causes significant protection against injurious TNFalpha in the setting of ischemia. Our studies suggest that TNFalpha is a twin-edged sword in the setting of stroke: TNFalpha upregulation is needed to establish LPS-induced tolerance before ischemia, whereas suppression of TNFalpha signaling during ischemia confers neuroprotection after LPS preconditioning. 相似文献
102.
103.
104.
105.
A 60 year old male patient is introduced who developed a loss of vision caused by chorioretinal cystic alteration in the macula of the left eye 9 months after a routine extracapsular cataract surgery with implantation of posterior chamber lens. There existed no other general symptoms, hematologic values and serology were regular. Having discussed literature the diagnosis of solitary Toxocara canis granuloma was produced. 相似文献
106.
Alexander Marcus Claudia Ammermann Marianne Klein Martin H. Schmidt 《European child & adolescent psychiatry》1995,4(1):46-54
Wilson's disease is a hereditary autosomal recessive disorder of copper metabolism. The corresponding gene locus has been localized on the long arm of chromosome 13. Three different clinical variants of the disease can be distinguished: hepato-cerebral, abdominal/hepatic, and central nervous type. The heterogeneity of symptoms can cause problems in differential diagnosis, especially when another concordant disorder can also explain the pathogenesis of symptoms. The case report of a young man who suffered from brainstem contusion demonstrates the possibilities of misinterpretation because presenting symptoms could be attributed either to traumatic brain injury followed by adjustment disorder or Wilson's disease. Clinical signs included leftsided hemiparesis, bilateral gaze direction nystagmus, marked dysarthria with consecutive pervasive mutism, choreo-athetoid movements, spasmodic torticollis and diplopia dependent on gaze direction. Slit lamp examination showed Kayser-Fleischer's corneal ring. EEG- and computer assisted tomography investigations revealed non-specific findings. The patient was treated with D-Penicillamine. Alternative treatment with oral zinc preparations is discussed.
Zusammenfassung Beim Morbus Wilson handelt es sich um eine autosomal rezessiv vererbte Störung des Kupferstoffwechsels. Der Genort konnte auf dem langen Arm des Chromosoms 13 lokalisiert werden. Klinisch können aufgrund ihrer Symptomatik drei Verlaufsformen (hepato-zerebraler, abdominalhepatischer und zerebraler Typ) unterschieden werden. Die Vielfalt der Symptome kann differentialdiagnostische Schwierigkeiten bereiten. Das Beispiel eines jungen Mannes mit einer traumatischen Hirnstammkontusion zeigt, wie die Diagnose der hepato-lentikulären Erkrankung dadurch erschwert wurde, daß die Pathogenese der Symptome durch die Hirnstammkontusion und darauf folgende Anpassungsstörungen erklärt worden war. Die Symptomatik bestand aus linksseitiger Hemiparese, lateralem Blickrichtungsnystagmus, Dysarthrie mit nachfolgendem universalem Mutismus, choreo-athetodischen Bewegungsstörungen, Torticollis spasmoidicus und blickrichtungsabhängigem Auftreten von Doppelbildern. Bei der Spaltlampenuntersuchung stellte sich der Kayser-Fleischer Ring dar. EEG- und computertomographische Untersuchungen erbrachten nur unspezifische Befunde. Die Behandlung erfolgte mit D-Penicillamin. Die alternative Behandlung mit oraler Gabe von Zinksalzen wird diskutiert.
Résumé La maladie de Wilson est une affection héréditaire autosomale recessive concernant le métabolisme cuivré. Le locus du gène a été situé sur le bras long du chromosome 13. Du point de vue clinique on distingue trois formes symptomatologiques: le type hepato-cérébral, hepato-abdominal et cérébral. La diversité des signes cliniques peut poser des problèmes de diagnostic différentiel, car d'autres affections peuvent se présenter avec cette même Symptomatologie. Nous rapportons ici l'exemple d'un homme jeune, porteur d'une maladie de Wilson et victime d'une contusion traumatique du tronc cérébral, dont les signes cliniques ainsi que les troubles du comportement pouvaient été autant rapportés à la contusion du tronc cérébral qu'à l'affection métabolique.La Symptomatologie comprenait une hemiparesie gauche, un nystagmus lateralisé, une dysarthrie avec mutisme secondaire universel, des mouvements choréo-athétosiques, un torticolis spasmodique et une diplopie dépendante de la direction du regard. L'examen à la lampe à fente permettait à mettre en evidence un anneau de Kayser Fleischer. L'EEG et le scanner cérébral ne montraient pas d'anomalies specifique.Le traitement a consisté en l'administration de D-Penicillamine. Traitment alternative avec les sels de zinc est discuté.相似文献
107.
Excess of DD homozygotes in haemodialysed patients with type II diabetes. The Diabetic Nephropathy Study Group 总被引:1,自引:0,他引:1
Schmidt S; Strojek K; Grzeszczak W; Bergis K; Ritz E 《Nephrology, dialysis, transplantation》1997,12(3):427-429
The role of the insertion/deletion polymorphism of the angiotensin-
converting enzyme (ACE) gene in the genesis of diabetic nephropathy has
been controversial. It has recently been proposed that progression occurs
more rapidly in individuals with diabetic and non-diabetic renal disease
who are homozygous for the D allele. We studied 658 patients with type II
diabetes, 347 without diabetic nephropathy and 311 with various stages of
diabetic nephropathy, and determined the I/D polymorphism of the ACE gene.
Patients at the extremes of renal risk, i.e. normotensive patients without
antihypertensive treatment and without nephropathy (n = 144), vs patients
on dialysis (n = 61), differed with respect to genotype (DD 36.8% vs 57.4%;
P = 0.007) and allele frequencies (D 0.59 vs 0.76; P < 0.001). In
contrast, patients with and without presumed nephropathy as assessed by
albuminuria did not differ with respect to DD genotype. In conclusion, in
this study, which was limited by sample size, patients with the highest
renal risk more frequently had the DD genotype. This would be compatible
with a greater risk of (or rate of) progression to end-stage renal failure.
相似文献
108.
109.
Mary ER O'Brien Janet Hardy Sylvia Tan Jackie Walling Brian Peters Sarah Hatty Eve Wiltshaw 《Cancer chemotherapy and pharmacology》1992,30(3):245-248
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted. 相似文献
110.
G Grossmann L Otto C Felder M Clausen P Kress A Schmidt E Henze V Hombach 《Zeitschrift für Kardiologie》1992,81(1):9-14
In 40 patients (pts) (ages 34-83 years) the severity of tricuspid regurgitation (TR) was graded by pulsed Doppler echocardiographic determination of regurgitant jet extension. Mild TR was assessed in seven pts (group I), mode-rate TR in 20 pts (group II), and severe TR in 13 pts (group III). The enddiastolic diameter of the left ventricle as measured by M-mode-echocardiography was 55 +/- 16 mm in group I, 48 +/- 6 mm in group II, and 50 +/- 10 mm in group III. The regurgitant index (RI), i.e., the ratio of left-to-right-ventricular stroke counts (normal range 0.89-1.97) and the time-activity curve over the liver area were measured by equilibrium radionuclide ventriculography (RNV). The RI differed significantly between group I (1.6 +/- 0.5), II (1.0 +/- 0.3), and III (0.8 +/- 0.3) (p less than 0.01). An RI-value below 0.89 as an index of right-ventricular volume overload was found in 14% (group I), 45%, (group II) and 77% (group III). The time-activity curve over the liver area, as graded by count variation in phase with the right atrium from 1 (no count variation) to 4 (typical count variation) showed all grades in groups I and II, but only grade 2 to 4 in group III. The RI resp. the time-activity curve over the liver is a sensitive parameter for the detection of moderate to severe TR. If TR is ascertained, severe regurgitation can be differentiated from mild regurgitation by RNV-derived RI as an index of right-ventricular volume overload. 相似文献