Comparison of Lens Biochemistry and Structure between BSO-treated and Glucocorticoid-treated Developing Chick Embryos

In this paper various changes in glutathione level, which were influenced by balance of its synthesis, degradation, transport and utilization, were analysed in chick embryos administered with glucocorticoid (GC) or buthionine sulfoximine (BSO; an inhibitor of glutathione synthesis). When BSO (30 μmol egg⁻¹) was administered twice to chick embryos on day 14 and 15, the GSH in both the lens and the liver decreased to 15–20% and 30–40% of the age-matched control level, respectively, between 24 and 48 hr after the second treatment, then began to recover. Although this decline in the GSH level in these tissues was greater and more prolonged in embryos treated with BSO than with GC, the former embryos maintained lens transparency even up to 144 hr by a visual examination. However, histological changes in the lens occurred after 96 hr and more significantly 144 hr after second administration of BSO. The changes mainly consisted of pale epithelial cells on the anterior peripheral surface of the lens, irregular height of the epithelial cells at the equator, clefts between the epithelium and the cortex and swelling of almost all the cortical fibers. These observations may suggest that BSO treatment could produce the beginning of a cataract. Embryos with GC-cataract revealed the following changes at 48 hr: loss of transparency, elevation of LPO (TBA-reacting substance) in the lens, the blood and the liver. These were not observed in BSO-treated embryos during the experimental period. The GC-cataract may well depend on the generation of LPO. BSO cataract, having a distinct mechanism compared to that caused by GC, develops more slowly in GSH-depleted lenses. The BSO-treated chick embryos will be a useful model to screen the risk factors which accelerate cataract formation.     

Serum hyaluronic acid reflects the effect of interferon treatment on hepatic fibrosis in patients with chronic hepatitis C

Changes in serum hyaluronic acid (HA) in 35 patients treated with interferon (IFN) were studied and the histological change in fibrosis was analysed. Serum HA levels and hepatitis C virus (HCV) RNA were followed from the start of therapy to 12 months after completion of treatment. Histological changes in pre- and post-treatment liver biopsies were assessed using a modified Knodell's scoring system. The serum levels of HA (r = 0.79; P<0.0001) correlated with the degree of fibrosis more closely than with that of amino terminal peptides of type III procollagen (PIIIP; r = 0.45; P<0.05) or type IV collagen (IV-C; r = 0.42; P<0.05). Only complete responders (CR) had a significant decrease in serum levels of HA and IV-C (P<0.05), in parallel with histological improvement (P<0.01). Neither partial responders (PR) nor non-responders (NR) had significant changes in histological scores and in serum levels of fibrotic markers. Significant differences were observed between CR and NR, both in HA levels (P<0.01) and PIIIP levels (P<0.05) 12 months after the cessation of treatment. These results suggest that serum HA is an indicator of the extent of fibrosis in chronic hepatitis C. Serial determinations of serum HA levels may be of use for monitoring the histological response of hepatic fibrosis to IFN treatment in chronic hepatitis C.     

Cerivastatin inhibits fetal calf serunvinduced DNA synthesis in cultured rat mesangial cells

SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC₅₀ was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.     

Prognostic significance of vascular invasion in patients with bladder cancer who underwent radical cystectomy

BACKGROUND: The objective of this study was to determine whether vascular invasion (i.e. lymphatic and blood vessel invasion) could be a useful prognostic predictor in patients with locally invasive transitional cell carcinoma (TCC) of the bladder who underwent radical cystectomy. METHODS: This series included 114 consecutive patients undergoing radical cystectomy for primary TCC of the bladder between November 1989 and July 2003. Several clinicopathological characteristics of these patients were analyzed, focusing on the association between vascular invasion and disease recurrence after radical cystectomy. RESULTS: Lymphatic and blood vessel invasions were detected in 55 (48.2%) and 33 (29.8%) specimens, respectively. Lymphatic invasion was significantly associated with pathological stage, tumor grade, lymph node metastasis, blood vessel invasion and disease recurrence, whereas blood vessel invasion was significantly related to pathological stage, lymph node metastasis, lymphatic invasion and disease recurrence. Recurrence-free survival in patients with lymphatic invasion was significantly lower than that in those without lymphatic invasion, and a similar significant difference in recurrence-free survival was observed between patients with and without blood vessel invasion. However, multivariate analysis using the Cox proportional hazards model showed that only pathological stage and lymph node metastasis could be used as independent predictors for disease recurrence after radical cystectomy. CONCLUSIONS: Despite a significant association between several prognostic parameters, vascular invasion was not an independent predictor of disease recurrence; therefore, if there are other conventional parameters available, there might not be any additional advantage to considering the presence of vascular invasion when predicting the prognosis of patients undergoing radical cystectomy for TCC of the bladder.     

High dose chemotherapy including paclitaxel (T-ICE) combined with peripheral blood stem cell transplantation for male germ cell tumor. Preliminary report

AIM: To evaluate the feasibility and usefulness of high dose chemotherapy including paclitaxel (T-ICE) combined with peripheral blood stem cell transplantation (PBSCT) for male germ cell tumor. METHODS: Five male patients with advanced germ cell tumor underwent 1-6 courses of high dose chemotherapy including paclitaxel (T-ICE; 175 mg/m2 of paclitaxel, 1250 mg/m2 of carboplatin, 1500 mg/m2 of etoposide and 7.5 g/m2 of ifosfamide) with PBSCT after 2-3 courses of induction chemotherapy (PEB or VIP). RESULTS: In all patients, serum marker levels decreased to within the normal range by T-ICE. Two patients underwent resection of residual tumor. In one patient, viable cancer cells were detected in resected lymph node tissue and adjuvant chemotherapy was then performed. Although the follow-up period was short (7-15.5 months), four of the five patients (80%) showed no evidence of recurrent disease. No significant differences in side-effects were noted between T-ICE and conventional high dose ICE, which was previously performed in 39 patients at the Division of Urology, Kobe University Graduate School of Medicine, Japan. CONCLUSIONS: High dose chemotherapy, including T-ICE, combined with PBSCT showed an almost identical degree of side-effects as seen in previous high dose chemotherapy without paclitaxel. Although 80% of the patients showed no evidence of disease so far, the efficacy of T-ICE should be evaluated with more patients and longer follow up.     

Is a limited lymphadenectomy targeting obturator nodes alone an adequate procedure for Japanese men undergoing radical prostatectomy?

BACKGROUND: The objective of the present study was to investigate the significance of pelvic lymphadenectomy during radical prostatectomy in Japanese men with prostate cancer. METHODS: A total of 178 consecutive patients who underwent radical prostatectomy and standard pelvic lymphadenectomy targeting the external iliac nodes and obturator fossa for clinically localized prostate cancer were studied. The median observation period of this series was 18 months (range: 3-36 months). RESULTS: Lymph node metastases were detected in 13 patients; that is, positive nodes were located in the external iliac nodes alone in seven patients, the obturator fossa alone in four patients, and both external iliac nodes and obturator fossa in two patients. Of these 13 patients, all of the seven with more than one positive node demonstrated biochemical recurrence, whereas five of the six with single node involvement remained without signs of biochemical recurrence. Furthermore, a single positive node was located in the external iliac region in five of the six patients. When a group at high-risk for lymph node metastasis was defined as those meeting more than two of the following three criteria: (i) pretreatment serum prostate specific antigen value > or = 20 ng/mL; (ii) biopsy Gleason sum > or = 8; or (iii) percentage of positive biopsy core > or = 50%, the incidence of lymph node metastasis was 24.5% in the high-risk group and 0.8% in the low-risk group. CONCLUSIONS: These findings suggest that limited dissection of the obturator node alone may not be sufficient for Japanese men undergoing radical prostatectomy; therefore, we recommend performing standard pelvic lymphadenectomy targeting both the external iliac nodes and the obturator fossa for patients at high-risk of lymph node involvement.     

Dipeptide synthesis catalyzed by aminoacyl-tRNA synthetases from Bacillus stearothermophilus

A new approach to enzymatic peptide synthesis by using aminoacyl-tRNA synthetase (ARS) as a catalyst has been investigated. Four ARSs (AspRS, HisRS, LeuRS and TyrRS) have been purified from a thermophilic bacterium, Bacillus stearothermophilus. By using TyrRS as a catalyst, tyrosine and leucinamide were shown to be condensed in the presence of ATP to give tyrosylleucinamide. In this manner, all of the ARSs investigated catalyzed the peptide synthesis reactions. TyrRS did not have strict specificity for the amino acid derivatives used as substrates and even D-amino acids were incorporated into peptides fairly easily in this enzymatic reaction. Preparative scale synthesis of L-Tyr-L-LeuNH₂ was carried out and from this the scope and limitation of this new enzymatic reaction as a tool to the peptide synthesis has been described.