Conformational preferences in a benzodiazepine series of potent nonpeptide fibrinogen receptor antagonists

Previously, we reported the direct design of highly potent nonpeptide 3-oxo-1,4-benzodiazepine fibrinogen receptor antagonists from a constrained, RGD-containing cyclic semipeptide. The critical features incorporated into the design of these nonpeptides were the exocyclic amide at the 8-position which overlaid the Arg carbonyl, the phenyl ring which maintained an extended Gly conformation, and the diazepine ring which mimicked the gamma-turn at Asp. In this paper, we investigate conformational preferences of the 8-substituted benzodiazepine analogues by examining structural modifications to both the exocyclic amide and the seven-membered diazepine ring and by studying the conformation of the benzodiazepine ring using molecular modeling, X-ray crystallography, and NMR. We found that the directionality of the amide at the 8-position had little effect on activity and the (E)-olefin analogue retained significant potency, indicating that the trans orientation of the amide, and not the carbonyl or NH groups, made the largest contribution to the observed activity. For the diazepine ring, with the exception of the closely analogous 3-oxo-2-benzazepine ring system described previously, all of the modifications led to a significant reduction in activity compared to the potent 3-oxo-1, 4-benzodiazepine parent ring system, implicating this particular type of ring system as a desirable structural feature for high potency. Energy minimizations of a number of the modified analogues revealed that none could adopt the same low-energy conformation as the one shared by the active (S)-isomer of the 3-oxo-1, 4-benzodiazepines and 3-oxo-2-benzazepines. The overall data suggest that the features contributing to the observed high potency in this series are the orientation of the 3-4 amide and the conformational constraint imposed by the seven-membered ring, both of which position the key acidic and basic groups in the proper spatial relationship.     

(-)-Epiafzelechin: cyclooxygenase-1 inhibitor and anti-inflammatory agent from aerial parts of Celastrus orbiculatus.

An inhibitor of cyclooxygenase (COX)-1 activity of prostaglandin H2 synthase was isolated from aerial parts of Celastrus orbiculatus Thunb. (Celastraceae), an oriental folk medicine for rheumatoid arthritis by activity-guided column chromatographic methods. The COX inhibitor was identified as (-)-epiafzelechin, a member of flavan-3-ols by the structural analysis with HR-EI-mass, 1H-NMR and 13C-NMR spectral data. The compound exhibited a dose-dependent inhibition on the COX activity with an IC50 value of 15 microM. (-)-Epiafzelechin exhibited about 3-fold weaker inhibitory potency on the enzyme activity than indomethacin as a positive control. (-)-Epiafzelechin exhibited significant anti-inflammatory activity on carrageenin-induced mouse paw edema when the compound (100 mg/kg) was orally administrated at 1 h before carrageenin treatment.     

Effect of DW2282 on the induction of methemoglobinemia, hypoglycemia or WBC count and hematological changes

DW2282,(S)-(+)-4-phenyl-1-[1-(4-aminobenzoyl)-indoline-5-sulfonyl] -4,5-dihydro-2-imidazolone hydrochloride, is a new anticancer agent which is thought to exhibit a characteristic mechanism of action in the inhibition of tumor growth. In this study, we estimated the toxicities of DW2282 in mice. When mice were orally dosed for five consecutive days at the dosages of 50, 100 and 150 mg/kg, DW2282 did not induce methemoglobinemia and hypoglycemia at any of these doses. However, increased ALT and AST values were observed in the 150 mg/kg dosing group, and white blood cells (WBC) were significantly decreased at all doses. However, the changes in WBC count, ALT and AST immediately reversed after the cessation of drug administration. In addition, we found that DW2282 did not cause an increase in hemolysis in human blood. Taken together, these data suggested that DW2282 may have a relatively low level of toxicity, and that there may be a quick recovery from any toxicity it does produce.     

Cytokines predict coronary aneurysm formation in Kawasaki disease patients

In this study, we measured serially the serum levels of cytokines including interleukin-6 (IL-6), IL-8, soluble IL-2 receptor (sIL-2R) and tumour necrosis factor (TNF-) in 60 patients with Kawasaki disease (KD) and evaluated the clinical significance of these cytokines in predicting coronary aneurysm formation. Of the 60 patients, 12 were complicated with coronary aneurysm. Blood samples were collected within the 1st week after onset of fever, then once a week for the 1st month, and once a month for another 5 months. The serum levels of IL-6, IL-8, sIL-2R and TNF were measured using an ELISA or RIA method. Our results show that the changes in serum IL-6 and IL-8 were faster than those of sIL-2R and TNF. Within the 1st week, the serum levels of IL-6 and IL-8 were significantly higher in the patients with than in those without coronary aneurysm (P<0.001). In addition, the serum levels of IL-6 and IL-8 obtained in the 1st week were highly correlated (P<0.001) with those of C-reactive protein and erythrocyte sedimentation rate, and the serum levels of sIL-2R and TNF were also increased at the 1st week reaching the highest level in the 2nd week. In the 2nd week, the serum levels of sIL-2R and TNF were significantly higher in the patients with than in those without coronary aneurysm (P<0.05). These findings suggest that the serum levels of IL-6 and IL-8 obtained in the 1st week may serve as useful parameters in predicting coronary aneurysm formation in KD patients.     

Central core disease--a case report.

Central core disease is a rare congenital myopathy characterized by the formation of "cores" that consist of abnormal arrangement of myofibrils inside the myofibers. We report a 5-year-old Korean girl who showed a fairly typical clinical course of non-progressive muscle weakness. Electrodiagnostic studies showed low-amplitude polyphasic electromyograph and normal nerve conduction velocity. Gastrocnemius muscle biopsy showed central cores in over 80% of the fibers on H&E section. Histochemistry revealed deficient or absent mitochondrial enzyme in the cores and type I predominance. Ultrastructurally both structured and non-structured cores were found separately or simultaneously in one fiber. This case is the first report in the Korean literature.     

Inflamed fibronectin: an altered fibronectin enhances neutrophil adhesion

Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation.     

Takayasu's arteritis: diagnostic considerations and surgical treatment

A 20-year-old white woman with Takayasu's arteritis had headaches, neck soreness, and a right carotid bruit. Corticosteroid treatment only temporarily relieved symptoms and caused Cushing's syndrome because of high dosage requirements. Progressive narrowing of the right common carotid artery occurred despite treatment. The diseased portion of the artery was successfully resected and replaced by a Dacron graft. Corticosteroid treatment was then tapered and discontinued, and the patient has remained well for 3 years. Carotid Doppler and real-time ultrasound studies performed more than 2 years after surgery showed a patent graft and no new disease process. This technique may be of value in selected cases for both prevention of cerebral ischemia and the elimination of local symptoms of the inflammatory process.     

Early characteristic findings in bowleg deformities: evaluation using magnetic resonance imaging

We used magnetic resonance imaging (MRI) to evaluate bowleg deformities in infancy. Twenty-five tibiae of 13 infants were examined and divided into two groups based on MRI findings: group A had high intensity area in the medial epiphyseal cartilage on T2-weighted images. Group B had depression of medial physis and abnormal signal in the perichondrial region in addition to the epiphyseal lesion. At the final follow-up, all cases in group A demonstrated normal lower leg alignments, whereas five cases in group B showed characteristic roentogenographic findings of Blount's disease. The improvement rate of metaphyseal-diaphyseal angle was correlated with this classification. These findings suggested that abnormal findings in physis and perichondrial region might be preliminary findings in early stage of Blount's disease. The high intensity areas in the medial epiphyseal cartilage were commonly found among the cases with bowing deformities, which suggested that there might be a common pathomechanism between physiologic bowing and infantile Blount's disease.