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Mutations in the X-linked gene CDKL5 cause early-onset epileptic encephalopathy and severe developmental delay. Because this disorder predominantly affects females, the full clinical spectrum of male patients remains elusive. We herein report a 16-year-old boy, who suffered from intractable seizures 20 days after birth. Serial electroencephalograms detected recurrent focal epileptiform discharges from age 4 months, which evolved to hypsarrhythmia later in infancy. Mass-spectrometric analyses revealed increase in urinary excretion of methylmalonic acid without perturbed concentrations of propionic acid, homocystein and methionine. Whole-exome sequencing identified a de novo, truncating mutation in CDKL5 (NM_003159.2:c.419dupA, p.Asn140Lysfs*8). Targeted sequencing excluded concomitant mutations in methylmalonic academia-associated genes. No methylmalonic acidemia has been reported in children with CDKL5 disorder. Extensive analyses on organic acid metabolism for males with CDKL5 mutations will gain more insight into their biochemical profiles in infancy.  相似文献   
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Expression of urokinase-type plasminogen activator (uPA) is increased after brain injury, suggesting that, like in cancer tissue, uPA plays roles in brain remodeling. Here we injured brain with intrahippocampal kainic acid (KA) injection in adult Wt and uPA?/? mice. At 20 days post-injury, uPA?/? mice had more severe loss of contralateral pyramidal (p < 0.05) and hilar neurons (p < 0.05) than Wt mice. The number of doublecortin (DCX)-positive newly born neurons was also reduced in uPA?/? mice as compared to Wt (p < 0.01). No difference was observed in granule cell dispersion or distribution of DCX-positive neurons in the dentate gyrus. uPA deficiency did not affect the total length of hippocampal blood vessels or vessel density. No differences were observed in the severity of status epilepticus or consequent epilepsy between the genotypes. These data indicate that uPA deficiency can unfavorably modulate both delayed neurodegeneration and neurogenesis but has little effect on post-injury neuronal migration and vascular density. Our results favor the idea that elevated uPA during the post-injury phase is neuroprotective.  相似文献   
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Pharmaceutical Research - To elucidate the stereoselective pharmacokinetics of omeprazole enantiomers and their metabolites after racemic IV dosing because there is little information about the...  相似文献   
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OBJECTIVE

Fulminant type 1 diabetes is characterized by the rapid onset of severe hyperglycemia and ketoacidosis, with subsequent poor prognosis of diabetes complications. Causative mechanisms for accelerated β-cell failure are unclear.

RESEARCH DESIGN AND METHODS

Subjects comprised three autopsied patients who died from diabetic ketoacidosis within 2–5 days after onset of fulminant type 1 diabetes. We examined islet cell status, including the presence of enterovirus and chemokine/cytokine/major histocompatibility complex (MHC) expressions in the pancreata using immunohistochemical analyses and RT-PCR.

RESULTS

Immunohistochemical analysis revealed the presence of enterovirus-capsid protein in all three affected pancreata. Extensive infiltration of CXCR3 receptor–bearing T-cells and macrophages into islets was observed. Dendritic cells were stained in and around the islets. Specifically, interferon-γ and CXC chemokine ligand 10 (CXCL10) were strongly coexpressed in all subtypes of islet cells, including β-cells and α-cells. No CXCL10 was expressed in exocrine pancreas. Serum levels of CXCL10 were increased. Expression of MHC class II and hyperexpression of MHC class I was observed in some islet cells.

CONCLUSIONS

These results strongly suggest the presence of a circuit for the destruction of β-cells in fulminant type 1 diabetes. Enterovirus infection of the pancreas initiates coexpression of interferon-γ and CXCL10 in β-cells. CXCL10 secreted from β-cells activates and attracts autoreactive T-cells and macrophages to the islets via CXCR3. These infiltrating autoreactive T-cells and macrophages release inflammatory cytokines including interferon-γ in the islets, not only damaging β-cells but also accelerating CXCL10 generation in residual β-cells and thus further activating cell-mediated autoimmunity until all β-cells have been destroyed.Fulminant type 1 diabetes is characterized by abrupt onset of severe hyperglycemia and ketoacidosis preceded by flu-like symptoms including fever, abdominal pain, and headache (13). Due to the rushed clinical course in most cases, patients with fulminant type 1 diabetes are sometimes untreated until becoming comatose and/or entering a critical, life-threatening state (4). Endogenous insulin secretion is completely abolished over time and diabetic microangiopathies develop over a short duration (5,6). The mechanisms underlying the aggressive and rapid destruction of β-cells have remained one of the major questions regarding this subtype of type 1 diabetes. However, in situ human data on affected islets and pancreas and possible mechanisms have been completely lacking for fulminant type 1 diabetes.Viral infection with subsequent immunological mechanisms represents one of the leading candidates for destruction of β-cells in fulminant type 1 diabetes (3,7). Some studies on the mouse model of lymphocytic choriomeningitis virus–induced type 1 diabetes have demonstrated that islet β-cells can be destroyed as follows: within 1 day after virus infection, CXC chemokine ligand 10 (CXCL10) (8), a key chemoattractant for activated T-cells and macrophages, is produced in β-cells and secreted from islets (9). Activated T-cells bearing the receptor for CXCL10, named CXCR3 (8), infiltrate and accumulate in islets secreting CXCL10 (10). Accumulated T-cells at the islets then destroy β-cells through cell-mediated mechanisms (11). With this mechanism, CXCL10 is necessary and sufficient for accelerated T-cell response with complete β-cell destruction and resulting type 1 diabetes (10,12,13). We have recently found that serum CXCL10 levels are increased at the onset of fulminant type 1 diabetes, suggesting a crucial role of the CXCL10-CXCR3 axis in the aggressive β-cell destruction in this syndrome (14). We therefore examined in situ status with regard to enterovirus infection, CXCL10-CXCR3 axis, major histocompatibility complex (MHC) molecule expression, and islet dysfunction in pancreata from patients with fulminant type 1 diabetes who died due to diabetic ketoacidosis within 2–5 days after outset of flu-like symptoms. Our in situ findings for affected pancreata provide new insights into understanding the pathogenesis of and developing interventional strategies against human type 1 diabetes.  相似文献   
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The detection of an ovarian mass during pregnancy is often a diagnostic challenge. We describe 2 cases of ovarian endometrioma during pregnancy with marked mural nodules on the cyst wall. The sonographic and MR imaging findings mimicked ovarian cancer. Surgical intervention may still be inevitable to exclude the possibility of malignancy.  相似文献   
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