In-vitro Characterization of YM872, a Selective,Potent and Highly Water-soluble α-Amino-3-hydroxy-5-methylisoxazole-4-propionate Receptor Antagonist

The in-vitro pharmacological properties of (2,3-dioxo-7-(1H-imidazol-***1-yl)-6-nitro-1,2,3,4-tetrahydro-1-quinoxalinyl)-acetic acid monohydrate, YM872, a novel and highly water-soluble α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)-receptor antagonist were investigated. YM872 is highly water soluble (83 mg mL^?1 in Britton-Robinson buffer) compared with 2,3-dihydroxy-6-nitro-7-sulphamoyl-benzo(F)quinoxaline (NBQX), 6-(1H-imidazol-1-yl)-7-nitro-2,3(1H,4H)-quinoxalinedione hydrochloride (YM90K) or 6-cyano-7-nitroquinoxa-line-2,3-dione (CNQX). YM872 potently inhibits [³H]AMPA binding with a K_i (apparent equilibrium dissociation constant) value of 0.096 ± 0.0024 μM. However, YM872 had very low affinity for other ionotropic glutamate receptors, as measured by competition with [³H]kainate (high-affinity kainate binding site, concentration resulting in half the maximum inhibition (IC50) = 4.6 ± 0.14 μm), [³H]glutamate (N-methyl-D-aspartate (NMDA) receptor glutamate binding site, IC50 > 100 μM) and [³H]glycine (NMDA receptor glycine-binding site, IC50 > 100 μM). YM872 competitively antagonized kainate-induced currents in Xenopus laevis oocytes which express rat AMPA receptors, with a pA₂ value of 6.97 ± 0.01. In rat hippocampal primary cultures, YM872 blocked a 20-μM AMPA-induced increase of intracellular Ca²⁺ concentration with an IC50 value of 0.82 ± 0.031 μM, and blocked 300-μM kainate-induced neurotoxicity with an IC50 value of 1.02 μM. These results show that YM872 is a potent and highly water-soluble AMPA antagonist with great potential for treatment of neurodegenerative disorders such as stroke.     

Efficacy of Endoscopic Prosthesis in T4 Cancer of the Intrathoracic Esophagus

No remarkable improvement has yet been achieved in the survival of patients with advanced intrathoracic esophageal cancer. In particular, patients with complications such as esophago-bronchial fistula or invasion into the mediastinum have an especially miserable prognosis, even with surgical treatment. To improve the quality of life (QOL) of such patients, extensive palliative therapy should be provided. Thus, we have introduced an endoscopic esophageal intubation technique for the treatment of stenosis or perforation in patients with T4 esophageal cancer. Nine patients with unresectable intrathoracic esophageal cancer, complicated by stenosis or perforation, were treated with an endoscopic esophageal prosthesis. Four cases had an esophago-bronchial fistula, and in three the tumor had perforated the mediastinum. The prosthesis was successfully placed under endoscopic guidance in all nine cases. Six patients (66.7%) subsequently resumed oral intake without discomfort, while two had reasonably good outcomes in this regard (efficacy rate; 88.9%). Complications were seen in three patients: mainly chest discomfort, reflux esophagitis and migration of the prosthesis in one patient each. Six patients required prolonged administration of chemotherapeutic agents following prosthesis placement. Mean survival was 123.4±77.0 days. Four of the nine patients died in the hospital. Palliative endoscopic esophageal prosthesis was considered to be useful for patients with advanced esophageal cancer. With this technique, an improvement in QOL was achieved, as sufficient oral intake was facilitated and pulmonary and mediastinal complications due to perforation were diminished.     

Serum Level of Interleukin-4 in Patients with Perennial Allergic Rhinitis During Allergen-Specific Immunotherapy

Interleukin-4 (IL-4) may play a central role in the IgE synthesis system, the development of Th-2-like cells, and co-ordination as well as the persistence of airway inflammatory process in allergic disorders. Therefore, IL-4 plays a key role in airway allergic disorders. This study aimed at investigating the serum concentrations of IL-4 in patients with perennial allergic rhinitis, with special reference to the possible changes and the clinical relevance following long-term immunotherapy. The study has demonstrated that the serum level of IL-4 in allergic rhinitis patients before immunotherapy is significantly higher than that in non-atopic individuals. However, the serum IL-4 level in allergic rhinitis patients did not decrease following anti-allergic medications but significantly decreased following immunotherapy. The percentage decrease in IL-4 was correlated significantly with the percentage decrease in specific IgE antibodies following long-term immunotherapy. Immunotherapy also significantly decreased specific IgE antibodies, but this reduction in specific IgE antibodies was not significantly correlated with the clinical improvement. In contrast, the percentage decrease in serum IL-4 was significantly correlated with the percentage decrease in symptomatic scores. The authors interpret these data to mean that immunotherapy alters T-cell cytokine profiles in the long-term, and a decline of IL-4 following immunotherapy could modulate not only production of specific IgE antibodies but also inflammatory cellular events, leading to symptomatic relief in allergic rhinitis.     

Electrophysiological Abnormalities of the Atrial Muscle in Patients with Manifest Wolff-Parkinson-White Syndrome Associated with Paroxysmal Atrial Fibrillation

We investigated the electrophysiological properties of the atrial muscle in 33 patients with manifest Wolff-Parkinson-White syndrome. Group I consisted of 13 patients with paroxysmal atrial fibrillation and group II consisted of 20 patients without paroxysmal atrial fibrillation. The anterograde and retrograde effective refractory periods of the accessory pathway and the inducibility of atrioventricular reciprocating tachycardia were not significantly different between the two groups. Endocardial electrograms, obtained by right atrial catheter mapping, were recorded during sinus rhythm from 12 sites of the right atrium in 12 of the 13 group I patients and in all group II patients. An abnormal atrial electrogram was defined as 100 msec or longer in duration, and/or the occurrence of eight or more deflections. Ten (83%) of the 12 group I patients had abnormal atrial electrograms, while only two (10%) of the 20 group II patients had abnormal atrial electrograms, and the difference was significant (P less than 0.01). Thirty-six (26%) of the total 139 electrograms obtained from 12 group I patients and two (1%) of the total 199 electrograms obtained from 20 group II patients fulfilled the criteria for an abnormal atrial electrogram, and the difference was significant (P less than 0.01). The fragmented atrial activity zone, interatrial conduction delay zone, and repetitive atrial firing zone obtained by right atrial extrastimulation were significantly wider in group I than in group II, respectively. It was concluded that electrical abnormalities of the atrial muscle may play an important role in the occurrence of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome.     

Epstein-Barr Virus in Normal Pregnant Women*

ABSTRACT: Acquired immune suppression accompanying normal pregnancy may be associated with reactivation of Epstein-Barr virus (EBV). Pregnant women with reactivated EBV having anti-EA antibodies show high titers of antiviral capsid antigen (VCA) geometric mean titers (GMT) of 522 versus 170 in those lacking anti-early antigen (EA). Among twenty-seven seropositive women at parturition, 17 (63%) had generated antibody to EA, and all 27 (100%) demonstrated significant increases in antibody to VCA (p < 0.01). In contrast, antibody titers to cytomegalovirus, herpes hominis, varicella-zoster, and rubella viruses in the pregnant women were comparable to those found in nonpregnant controls.     

Endoscopic Reduction of Acute Gastric Volvulus in a Child

Abstract: An 11-year-old girl with cerebral palsy was admitted with complaints of frequent vomiting and upper abdominal distension. After plain X-ray examination and upper gastrointestinal contrast study, she was diagnosed as having acute mesenterioaxial volvulus of the stomach. Endoscopic reduction was successfully performed. We describe herein the technical details of the endoscopic reduction in this rare case. In non-infant pediatric patients with primary gastric volvulus, we recommend that endoscopic reduction be considered prior to surgical intervention.     

转录调控因子CBF1（RBP—Jκ）对Cbfal和Ose2元件启动子活性的影响

目的：探讨Notch信号转录调控因子CBF1(RBP—Jκ)对核心结合因子Cbfal基因启动子和骨钙素基因启动子区域Ose2元件启动子活性的影响。方法：构建CBF1真核表达载体pCMV—Tag4／CBF1；将梯度浓度pCMV—Tag4／CBF1和荧光素酶报告质粒共转染两成骨前体细胞系Kusa—A1和Kusa-O，用双荧光素酶报告基因方法检测Cbfa1和Ose2元件启动子活性。结果：随CBF1浓度增加，Kusa—A1和Kusa-O细胞中Cbfa1和Ose2元件启动子活性均逐渐提高。统计分析表明：Kusa—A1细胞中1／40μg／μL实验组两启动子活性均与对照组差异显著；Kusa-0细胞中1／40μg／μL实验组Ose2元件启动子活性与对照组差异显著。结论：转录调控因子CBF1可以促进Cbfa1和Ose2元件启动子活性，从而可能对细胞的成骨性分化有正调节作用。