Species Differences of Serum Albumins: II. Chemical and Thermal Stability

Purpose. The chemical and thermal stability of five species of mammalian serum albumins (human, bovine, dog, rabbit, and rat) were investigated, and conformational stabilities were compared to obtain structural information about the different albumins. Methods. The chemical stability was estimated by using guanidine hydrochloride (GdnCl), and monitored by fluorometry and circular dichroism (CD). Thermal stability was evaluated by differential scanning calorimetry (DSC). Results. In human, bovine, and rat albumin, two transitions were observed when GdnCl-induced denaturation was monitored fluorometrically, indicating at least one stable intermediate, although, in dog and rabbit albumin, only one transition was observed. However, GdnCl denaturation, as monitored by the ellipticity, showed a two-state transition in all species used in this study. Since these proteins, showing two transitions, contained a conserved tryptophan residue within domain II, these structural changes might have occurred in domain II during intermediate formation. DSC measurements showed that human, bovine, and rat albumin exhibited single sharp endotherms and these were clearly consistent with a two-state transition, while the deconvolution analysis of broad thermograms observed for dog and rabbit albumin showed that the absorption peaks could be approximated by a two-component composition, and were consistent with independent transitions of two different cooperative blocks. Conclusions. These experimental results demonstrate that species differences exist with respect to the conformational stability and the mechanism of the unfolding pathway for mammalian albumin.     

Indole-3-carbinol inhibits the growth of human colon carcinoma cells but enhances the tumor multiplicity and volume of azoxymethane-induced rat colon carcinogenesis

Indole-3-carbinol (I3C) is a naturally occurring phytochemical which exerts a broad range of biological activities. The purpose of this study was to examine the effects of I3C on colon carcinogenesis, cell proliferation, cell-cycle progression and apoptosis, and on the levels of expression of several cell-cycle control molecules. We used a long-term rat model by using azoxymethane (AOM) to induce tumors (adenomas and adenocarcinomas) in the colon. In the present study, we found that after AOM injection, the treatment of male F344 rats with 0.01 and 0.05% I3C caused a significant increase in the tumor multiplicity of adenocarcinomas by 2.2- (P<0.05 for 0.01% I3C) and 2.1-fold (P<0.0002 for 0.05% I3C) respectively, when compared to the control rats. In addition, the tumor multiplicity of adenoma plus adenocarcinoma and the volume of adenocarcinoma were also increased by 2.0- (P<0.00001) and 2.1-fold (P<0.05) respectively, compared to the control. I3C significantly increased the proliferating cell nuclear antigen labeling index (PCNA LI) (P<0.008) and decreased the apoptotic index (P<0.05) of the colon adenocarcinoma. In contrast, in HCT 116 and HT29 human colon carcinoma cells, I3C inhibited growth and induced G1-phase cell-cycle arrest and apoptosis. Furthermore, I3C caused approximately a 2- to 4-fold increase in the cellular levels of p27KIP1 and p21CIP1 mRNA. These results suggest that I3C inhibits the growth of human colon carcinoma cells, at least in part, by inducing p27KIP1 and p21CIP1-mediated G1 cell-cycle arrest but dietary I3C promotes AOM-induced rat colon carcinogenesis by inhibiting the apoptosis of colon tumors. Therefore, the present study may provide further evidence for the ambivalent modulatory activity of I3C and this information may be useful when including I3C in cancer chemoprevention and/or extensive clinical therapy trials.     

Inhibitory effect of dietary monoglucosylceramide 1-O-beta-glucosyl-N-2'-hydroxyarachidoyl-4,8-sphingadienine on two different categories of colon preneoplastic lesions induced by 1,2-dimethylhydrazine in F344 rats

Sphingolipids display a wide spectrum of biological activities, including cell growth, differentiation and apoptosis. However, precise mechanisms by which these compounds exert anticancer or cancer-preventive effects are not known. In the present study, we evaluated the preventive efficacy of enriched dietary monoglucosylceramide 1-O-beta-glucosyl-N-2'-hydroxyarachidoyl-4,8-sphingadienine (G(1)CM) on 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) and beta-catenin-accumulated crypt (BCAC) formation in F344 rats during initiation stage. We also examined whether G(1)CM affects cell proliferation and apoptosis in these lesions. Pure G(1)CM was isolated from rice bran. Forty-two rats were divided randomly into five experimental groups. Rats in groups 1-3 were given subcutaneous injections of DMH (40 mg/kg body weight) once a week for 2 weeks. One week before the first injection of DMH, rats in groups 2 and 3 were fed a diet containing 200 and 1,000 p.p.m. G(1)CM, respectively, for 5 weeks. Rats in group 4 were fed a diet containing 1,000 p.p.m. G(1)CM. Rats in group 5 were given the basal diet alone and served as untreated controls. The experiment was terminated 5 weeks after the start. Dietary G(1)CM at both doses (groups 2 and 3) significantly inhibited the induction of ACF and BCAC (P<0.001) when compared to group 1 treated with DMH alone. In groups 2 and 3, the proliferating cell nuclear antigen labeling indices of epithelial cells in ACF and BCAC were also lower than in group 1 (P<0.0001 for ACF, P<0.05 for BCAC). These results, that dietary G(1)CM has possible chemopreventive effects in the present short-term colon carcinogenesis bioassays, suggest that longer exposure may cause suppression of tumor development.     

A case of giant epidermoid cyst occupying the testis

A case of a giant epidermoid cyst of the testis is presented. A 65-year-old man was incidentally pointed out to have left scrotal painless swelling. Physical examination revealed an over hen-egg sized enlargement of the left scrotal contents. Ultrasonography revealed a 7.5 X 5.5 X 4.0 cm solid tumor with heterogeneous echogenicity. No other abnormal findings were observed including tumor markers. Since preoperative examination did not rule out malignancy, we performed left high orchiectomy. Pathological diagnosis was a epidermoid cyst of the testis with a small portion of atrophic testis. Although the preoperative diagnosis of testicular epidermoid cyst is possible, it may be considerably difficult when a giant epidermoid cyst is occupying the testis.     

Heme oxygenase-1 accelerates protumoral effects of nitric oxide in cancer cells

We examined the biological effects of nitric oxide (NO) and its mediator, heme oxygenase-1 (HO-1), in cancer. Urogenital cancer cell lines, SKRC, T24 and DU145, were treated with various concentrations of sodium nitroprusside (SNP), a NO donor. The medium nitrite concentration was exponentially increased according to the concentration of SNP. Cell growth inhibition by NO was observed only at high nitrite concentrations (>20 M) in DU145 and T24 cells. Nitrite did not inhibit the growth of SKRC cells at any of the concentrations used. Doxorubicin (DXR) inhibited cell growth in the three cell lines, whereas growth inhibition recovered in the presence of <10 M nitrite. The recovery of DXR-induced growth inhibition was closely associated with an increase in Bcl-2 in the presence of <10 M nitrite. Vascular endothelial growth factor (VEGF) secretion was also increased in the presence of <10 and <20 M nitrite, respectively, in DU145 and SKRC or T24 cells. The expression of HO-1 was associated with sensitivity to NO-induced growth inhibition at constitutive levels, and was induced by SNP treatment. HO-1 inhibition by HO-1 antisense S-oligodeoxynucleotide treatment increased NO-induced growth inhibition, and decreased Bcl-2 expression or VEGF secretion in the three cell lines. These findings suggest that the NO/HO-1 system has protumoral effects.This work was supported by a Grant-in-Aid for Scientific Research (B) from the Japan Society for the Promotion of Science (KAKENHI: 15390130).     

Deep brain stimulation therapy for the vegetative state

Twenty-one cases of a vegetative state (VS) caused by various kinds of brain damage were evaluated neurologically and electrophysiologically three months after brain injury. These cases were treated by deep brain stimulation (DBS) therapy, and followed up for over 10 years. The mesencephalic reticular formation was selected as a target in two cases, and the thalamic centre median-parafascicular (CM-pf) complex was selected as a target in the other 19 cases. Eight of the 21 patients emerged from the VS, and became able to obey verbal commands. However, they remained in a bedridden state except for one case. DBS therapy may be useful for allowing patients to emerge from a VS, if the candidates are selected according to appropriate neurophysiological criteria. A special neurorehabilitation system may be necessary for emergence from the bedridden state in the treatment of VS patients. Further, DBS therapy is expected to provide a useful method in minimally conscious state (MCS) patients to achieve consistent discernible behavioural evidence of consciousness, and emergence from the bedridden state.     

Angioplasty for the intimal dissection of graft artery immediately after blood reflow: a successful case of renal transplantation

A 58-year-old woman, who had been suffering from chronic renal failure on hemodialysis since 1999, underwent living renal transplantation on January 14, 2003. The donor was her husband, and his left kidney was resected by a hand-assisted retroperitoneoscopic technique. Vascular clamps were removed after vascular anastomoses, but the color of two-thirds of the graft back side was dark, and urine excretion was not observed for 1 hour. The intimal dissection of the graft artery developed false lumen that occluded the blood flow to the transplanted kidney. The graft was resected from the recipient, and an angioplasty was performed for the false lumen of the graft artery after the second cold preservation. The graft with repaired artery was re-transplanted, and urine excretion was observed immediately after operation. Total ischemia time was 5 hours. Clinicopathological acute rejection episode and stenosis of graft artery did not occur for 6 months after operation. The intimal dissection of graft artery might occur at the time of catheterization on the perfusion for cold preservation and/or vascular anastomosis.     

Active chemotherapy with gemcitabine, carboplatin and docetaxel for three patients with MVAC-resistant liver metastasis of urothelial carcinoma

We report three cases with methotrexate-vinblastin-adriamycin-cisplatin (MVAC) resistant multiple liver metastases of urothelial carcinoma that responded to combination chemotherapy consisting of gemcitabine plus carboplatin (GC) with additional docetaxel (GCD) as salvage chemotherapy. Case 1: A 55-year-old man underwent left nephroureterectomy for ureteral cancer (TCC, G3, pT3pN1M0). Three courses of GC followed by three courses of GCD were given via intra-hepatic arterial infusion for multiple liver metastases, which appeared after adjuvant high-dose MVAC therapy. Complete response was obtained and maintained for 11 months. Case 2: A 46-year-old man underwent radical cystectomy for locally advanced bladder cancer (TCC G3 + adenocarcinoma. pT3pN0M0). Two courses of GC followed by 2 courses of GCD systemic therapies were performed for multiple liver metastases, which appeared after adjuvant high-dose MVAC therapy. Partial response was obtained and maintained for six months. Case 3: A 66-year-old man received three courses of MVAC for multiple metastases of the bladder cancer (TCC, G3, > pT2), which resulted in disease progression. Eight courses of GC followed by six courses of GCD were administrated via intra-hepatic arterial infusion. Partial response was obtained and maintained for 12 months. Although the response duration was still short, GC and GCD may be promising salvage chemotherapeutic regimens for the patients with MVAC-resistant liver metastases of urothelial carcinoma.     

Deep brain stimulation for the treatment of parkinsonian, essential, and poststroke tremor: a suitable stimulation method and changes in effective stimulation intensity

OBJECT: The tremor-suppression effect resulting from long-term stimulation of the thalamic nucleus ventralis intermedius (Vim) and the nucleus ventralis oralis posterior (Vop) was examined in the treatment of parkinsonian, essential, and poststroke tremor. METHODS: After identifying the accurate anterior border of the nucleus ventrocaudalis (Vc), deep brain stimulation (DBS) electrodes with four contacts were inserted into the Vim-Vop region at an angle of between 40 and 50 degrees from the horizontal plane of the anterior commissure-posterior commissure line. Two distal contacts were placed on the Vim side and two proximal contacts on the Vop side. The best sites of stimulation and parameters of bipolar stimulation were selected in each case and follow-up examinations were conducted for at least 2 years. In all 15 cases of parkinsonian tremor (18 sides) and in 14 of 15 cases of essential tremor (24 of 25 sides), cathodal stimulation of the Vim side with anodal stimulation of the Vop side was determined to be the best choice to suppress the tremor. In poststroke tremor, however, six of 12 cases (six of 12 sides) were selected for cathodal stimulation of the Vop side with anodal stimulation of the Vim side. The average stimulation intensity 1 month after initiation of DBS was 1.61 V in cases of parkinsonian tremor, 1.99 V in cases of essential tremor, and 2.39 V in cases of poststroke tremor. A comparison of stimulation intensities required at 1 and 24 months after initiation of DBS revealed that the lowest effective stimulation intensity increased 24.2% in cases of parkinsonian tremor, 21% in cases of poststroke tremor, and 46.9% in cases of essential tremor. Suppression of tremor was achieved in all cases (42 cases, 55 sides) during a period of 2 years. Nevertheless, two cases of poststroke tremor required dual-lead stimulation at the unilateral Vim-Vop region from the start of DBS, and two cases of essential tremor and one case of poststroke tremor required a stimulation intensity that was high enough to evoke unpleasant paresthesia and slight motor contraction during the follow-up period. CONCLUSIONS: Effective stimulation sites and stimulation intensities differ in different kinds of tremor; Vim and Vop stimulation is necessary in many cases. Interactions of the Vim and Vop under the control of interconnected areas of the motor circuitry may play an important role in both the development and DBS-induced suppression of tremor.