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The present study was undertaken to correlate calcium accumulation with the development of neuronal necrosis following transient ischemia. After 10 min of forebrain ischemia in the rat—a period that leads to reproducible damage of CA1 pyramidal cells—determination of calcium concentration and evaluation of morphological signs of cell body necrosis in the dorsal hippocampus were performed at variou
The effects of flunarizine, a calcium entry blocker, were evaluated in a long-term survival model of ischemia in rats. One group of animals received the drug orally at 24 and 4 h prior to the insult (40 mg·kg-1·dose-1). Another group was given flunarizine following the insult, intravenously at 5 min (0.1 mg·kg-1), and orally at 8 and 24 h (40 mg·kg-1·dose-1). A third group received the solvent for
The effect of deep isoflurane anesthesia on ischemically induced neuronal damage was evaluated in the rat. Sixteen mechanically ventilated animals were maintained normocapnic and normothermic while subjected to a near complete forebrain ischemia insult induced with systemic hypotension (MAP = 50± mmHg) and bilateral carotid artery occlusion. Prior to ischemia, eight of the rats received isoflurane
This study addresses the question of whether the cyclooxygenase inhibitors indomethacin and diclofenac and the glucocorticosteroid dexamethasone ameliorate neuronal necrosis following cerebral ischemia. In addition, since these drugs inhibit the production of prostaglandins and depress phospholipase A2 activity, respectively, the importance of free fatty acids (FFAs) on the development of ischemic
In this chapter, the pathophysiology and neurochemical pathology of epileptic brain damage is discussed on the basis of an integrative approach in which a comparison is made to cell necrosis resulting from ischemia and hypoglycemia. Two main questions are asked. First, is the brain damage resulting from these three disorders of cerebral energy metabolism similar in distribution and structural char
The possibility that neuronal damage due to hypoglycemia is induced by agonists acting on the N-methyl-D-aspartate (NMDA) receptor was investigated in the rat caudate nucleus. Local injections of an NMDA receptor antagonist, 2-amino-7-phosphonoheptanoic acid, were performed before induction of 30 minutes of reversible, insulin-induced, hypoglycemic coma. Neuronal necrosis in these animals after 1
Extracellular levels of striatal γ-aminobutyric acid (GABA) and taurine were monitored during insulin-induced hypoglycemia using microdialysis. At the onset of isoelectricity in the electroencephalogram (EEG), a transient 5-fold increase in the levels of GABA occurred. Taurine levels increased 5 min following the onset of isoelectricity and continued to increase during the entire isoelectric perio
Rats were exposed to insulin-induced hypoglycemia resulting in periods of cerebral isoelectricity ranging from 10 to 60 min. After recovery with glucose, they were allowed to wake up and survive for 1 week. Control rats were recovered at the stage of EEG slowing. After sub-serial sectioning, the number and distribution of dying neurons was assessed in each brain region. Acid fuchsin was found to s
Chemokines constitute a large family of low-molecular-weight proteins (∼10 kDa in size), recognized primarily for their role in directing leukocyte migration under both homeostatic and inflammatory settings. The chemokine CCL25 displays a unique and highly restricted expression pattern compared with other chemokine family members. In the steady state, CCL25 is expressed at high levels primarily in
The mucosal lymphocyte integrin α(E)(CD103)β7 is thought to be important for intraepithelial lymphocyte (IEL) localization or function. We cloned the murine integrin gene encoding α(E), localized it to chromosome 11, and generated integrin α(E)-deficient mice. In α(E)(-/-) mice, intestinal and vaginal IEL numbers were reduced, consistent with the known binding of α(E)β7, to E-cadherin expressed on
Microbial attachment to mucosal surfaces is a first step in mucosal infection. Specific interactions between microbial surface ligands and host receptors influence the distribution of microbes in their sites of infection. Adhesion has often been regarded as a sufficient end point, explaining tissue tropism and bacterial persistence at mucosal sites. Adherence, however, is also a virulence factor t
Urine and serum interleukin (IL)-6 and IL-8 responses were higher in children with febrile urinary tract infection (n = 61) than in those with asymptomatic bacteriuria (n = 39). By univariate analysis, cytokine levels were related to age, sex, reflux, renal scarring, urine leukocytes, C- reactive protein (CRP), erythrocyte sedimentation rate (ESR), and bacterial properties (P fimbriae but not hemo
This study analysed the effects of immunoregulatory cytokines on uroepithelial cell cytokine responses. The A-498 human kidney cell line was treated with the interleukins IL-2, IL-4, IL-5, IL-10, IL-12, IL-13, interferon gamma (IFN-α) and transforming growth factor beta (TGF-β1). Secreted IL-6 and IL-8 were quantitated by enzyme-linked immunoabsorbent assay (ELISA) and bioassay; IL-6 and IL-8 mRNA
Type 1 fimbriae are adhesion organelles expressed by many Gram-negative bacteria. They facilitate adherence to mucosal surfaces and inflammatory cells in vitro, but their contribution to virulence has not been defined. This study presents evidence that type 1 fimbriae increase the virulence of Escherichia coli for the urinary tract by promoting bacterial persistence and enhancing the inflammatory
Neutrophil influx to mucosal surfaces represents one of the earliest inflammatory responses to mucosal infection. We have been studying external interactions with urinary tract epithelial cells in an attempt to understand the molecular mechanisms behind this process. Uropathogenic Escherichia coli induced urinary tract epithelial cells to secrete the neutrophil chemoattractant interleukin-8 (IL-8)
During bacterial infections at mucosal sites, neutrophils migrate to the mucosa and cross the epithelial barrier. We have examined neutrophil migration across Escherichia coli-stimulated uroepithelial cell layers in an attempt to more fully understand this process. Stimulation of uroepithelial cells with E. coli or interleukin-1α (IL-1α) induced transepithelial neutrophil migration in a time- and
Localized at the border between the external environment and the internal tissue, epithelial cells are exposed to stimulants from two directions. Microorganisms in the lumen can activate the transcription of cytokine mRNA and cytokine secretion, and cytokines in the mucosal environment can modify endogenous and microbially induced epithelial cytokine responses. Epithelial cells thus actively parti
This study compared the cytokine production of uroepithelial cell lines in response to gram-negative bacteria and inflammatory cytokines. Human kidney (A498) and bladder (J82) epithelial cell lines were stimulated with either Escherichia coli Hu734, interleukin 1α (IL-1α), or tumor necrosis factor alpha (TNF-α). Supernatant samples were removed, and the RNA was extracted from cells at 0, 2, 6, and
Epithelial cell lines produce the cytokines IL-1α, IL-6 and IL-8 when stimulated with Escherichia coli. The cytokine response is enhanced by P fimbriae. The epithelial cell lines also respond to stimulation with other cytokines. These in vitro findings were confirmed in vivo in patients with E. coli infection who secreted IL-6 and IL-8 into the urine. The observations suggest that epithelial cells
