Nuclear magnetic resonance studies on polymer carbanions, 5. Polystyryl carbanion with lithium as counter cation and its dimer model compounds

Oligostyryllithium was synthesized by the reaction of sec-butyllithium with styrene in diethyl ether at ?40°C. Dimer model anions (counter cations: Li and K) of the growing chain ends were synthesized by metallation of 1-methoxy-1,3-diphenylpropane. The structures of the lithium compounds were corroborated by ¹³C NMR spectroscopy and compared with those of the potassium compounds. As for polystyryllithium and its model compounds, the charge density on the α-carbon increased and that on the phenyl ring of the growing end decreased with increasing molecular weight, while, in polystyrylpotassium and its model compounds, the charge density on the α-carbon increased and the one on the phenyl ring did not change with increasing molecular weight. The temperature change of the ¹H NMR spectrum of oligostyryllithium in diethyl ether indicated rotation around the C-1? C_α bond at lower temperatures than in tetrahydrofuran, but the activation energy was the same in both solvents. T₁ values of the phenyl carbons in model compound 2b were one to two orders of magnitude shorter than those of the protonated compound.     

Retinoblastoma protein prevents staurosporine-induced cell death in a retinoblastoma-defective human glioma cell line.

OBJECTIVE: To investigate the mechanism of staurosporine-induced glioma cell death and cell cycle arrest using adenovirus-mediated gene transfection, as well as the function of retinoblastoma (Rb) and genetic instability induced by staurosporine. METHODS: Cell cycle regulation, cell death and nuclear abnormalities induced by staurosporine were examined using an adenovirus vector expressing Rb, p16 or p21 genes in human glioma cell lines. RESULTS: The Rb-defective SF-539 cell line was resistant to staurosporine compared with cell lines expressing intact Rb. SF-539 glioma cells exposed to staurosporine became multinucleated and then died. Multinucleation was prevented in SF-539 cells transfected with the Rb gene, thus decreasing the death rate of these cells. CONCLUSIONS: These results imply that enforced Rb expression protects cells from genomic instability induced by staurosporine regardless of its upstream molecular effects.     

Evidence of cross-link formation of vitreous collagen during experimental ocular inflammation

Purpose: To determine the mechanisms of vitreous changes during ocular inflammation. Methods: We investigated vitreous changes, with special emphasis on collagen, in an experimental model of ocular inflammation induced by intravitreal injection of endotoxin (Escherichia coli) in rabbits. Results: Inflammation caused gel contraction and loss of elasticity, accompanied by release of a water-like liquid from the gel, and increases in the amount of insoluble material and highmolecular-weight components of vitreous collagen, presumably due to extensive cross-links of the collagen molecules. Those changes were partially inhibited by intravitreal injection of superoxide dismutase. Conclusions: The crosslinks of vitreous collagen may promote vitreous gel contraction and release of a water-like liquid from the gel. Superoxide anion may play a role in this process.     

Multicentric Castleman's disease associated with renal amyloidosis and pure red cell aplasia

 A 50-year-old man was admitted suffering from severe anemia and renal dysfunction. He had been admitted for the first time at the age of 49, and was diagnosed with multicentric Castleman's disease (MCD) and secondary amyloidosis. At that time, marked erythroid hypoplasia was demonstrated by both aspiration and biopsy of bone marrow. A diagnosis of pure red-cell aplasia (PRCA) was made. Immunosuppressive agents improved his symptoms and laboratory data. We report here a very rare case of PRCA following MCD and amyloidosis, and with reference to the literature, we discuss the relation between MCD and related diseases. Received: February 12, 1998 / Accepted: June 17, 1998     

Poor Survival Rate in Patients with Postoperative Intra-Abdominal Infectious Complications Following Curative Gastrectomy for Gastric Cancer

Background

The impact of postoperative complications on recurrence rate and long-term outcome has been reported in patients with colorectal and esophageal cancer, but not in patients with gastric cancer. This study evaluated the impact of postoperative intra-abdominal infectious complications on long-term survival following curative gastrectomy.

Methods

This study included 765 patients who underwent curative gastrectomy for gastric cancer between 2002 and 2006. Patients were divided into 2 groups: with (C-group, n = 81) or without (NC-group, n = 684) intra-abdominal infectious complications. Survival curves were compared between the groups, and multivariate analysis was conducted to identify independent prognostic factors.

Results

Male patients were dominant, and total gastrectomy was frequently performed in the C-group. The pathological stage was more advanced and D2 lymph node dissection and splenectomy were preferred in the C-group. The 5-year overall survival (OS) rate was better in the NC-group (86.8 %) than in the C-group (66.4 %; P < .001). The 5-year relapse-free survival (RFS) rate was also better in the NC-group (84.5 %) than in the C-group (64.9 %; P < .001). This trend was still observed in stage II and III patients after stratification by pathological stage. Multivariate analysis identified intra-abdominal infectious complication as an independent prognostic factor for OS (hazard ratio, 2.448; 95 % confidence interval [95 % CI], 1.475–4.060) and RFS (hazard ratio, 2.219; 95 % CI, 1.330–3.409) in patients with advanced disease.

Conclusions

Postoperative intra-abdominal infectious complications adversely affect OS and RFS. Meticulous surgery is needed to decrease the complication rate and improve the long-term outcome of patients following curative gastrectomy.     

Preoperative assessment of hemifacial spasm by the coronal heavily T2-weighted MR cisternography

Background

Microvascular decompression (MVD) has become a well-established surgical procedure for hemifacial spasm (HFS). Before surgery, it is essential to evaluate any possible deformity of the brainstem and establish the precise location of the offending vessels. In the present study of HFS patients we examined coronal sections taken by heavily T2-weighted MR cisternography in addition to routine axial sections, and assessed the usefulness of these images through comparison with intraoperative findings.

Methods

Eighty patients with HFS underwent preoperative coronal heavily T2-weighted MR cisternography before microvascular decompression surgery. Three neurosurgeons examined the preoperative axial and coronal MR images and evaluated vessel invagination into the brainstem. The usefulness of coronal sections was assessed statistically by the Mann-Whitney U test.

Results

Invagination of the offending vessel into the brainstem was observed in 24 cases (30.0%). In 19 patients, it was predicted preoperatively that compression of the flocculus and brainstem would be required in order to approach the offending vessels. Coronal MR cisternography was significantly more useful in cases with vessel invagination into the brainstem than in cases without invagination.

Conclusions

Coronal sections obtained by MR cisternography are able to demonstrate the severity of vessel invagination into the brainstem as well as revealing the presence of the offending vessel. This information is helpful for planning a suitable approach to the root exit zone.