Chronic hypertension induced by streptozotocin in rats

Summary An intravenous injection of 40 or 65 mg/kg streptozotocin induced not only diabetes but also severe hypertension in rats. Whereas the hyperglycemia developed fully within a few days after the injection of streptozotocin, the hypertension progressively advanced and reached maximum level several weeks after the treatment and lasted more than 20 weeks. Twenty mg/kg streptozotocin did not induce hyperglycemia but significantly increased blood pressure several weeks after the treatment. Arrest of growth, polyuria, glycosuria, hyperlipemia and lenticular cataracts developed in the animals treated with 40 or 65 mg/kg streptozotocin, but in none of the animals treated with 20 mg/kg. In histological examinations in the 24th week after the treatment, degranulation and necrosis in the pancreatic -cells, and vacuolization and deposition of PAS-positive materials in the renal proximal tubules were found in the animals treated with 40 or 65 mg/kg streptozotocin.     

Pharmacokinetic study of low- versus high-dose medroxyprogesterone acetate (MPA) in women

The present study was conducted to compare the pharmacokinetics (PK) of low-dose versus high-dose medroxyprogesterone (MPA) as a once-daily oral administration. Of 32 patients, all women, enrolled in this PK study, 18 received 600 mg MPA daily and 14 received 1200 mg daily. Detailed PK data were obtained on day 1 and after more than 4 weeks of MPA treatment. In addition, multiple data for the minimum steady-state concentration (Css min) were analyzed. The MPA serum concentrations were measured by high-performance liquid chromatography. Wide interpatient variability was found in the PK parameters obtained both on day 1 and after more than 4 weeks. There were no clear relationships between the oral dose and the MPA peak concentration (Cmax), area under the time versus concentration curve (AUC), or mean Css min. Weight gains of 10% or more were demonstrated more frequently in the high-dose group (P<0.01). Liver dysfunction (n=5) did not influence the PK of MPA. Five patients demonstrated extremely low AUC and Cmax (<10 ng/ml) values on day 1. Phenobarbital, dexamethasone and betamethasone were being taken concomitantly with the MPA each by one patient. The serum MPA concentrations were markedly increased after the discontinuation of phenobarbital in that patient, suggesting a drug interaction. At present we cannot recommend the high dose of MPA, except in clinical studies, from a PK or a pharmacodynamic points of view. Received: 2 May 1997 / Accepted: 13 October 1997     

Profiling of proteins phosphorylated or dephosphorylated during hyperactivation via activation on hamster spermatozoa

Background and Aims  It has been widely accepted that sperm hyperactivation is regulated by protein phosphorylations. But, the sperm hyperactivation phosphorylation pathway is not well understood yet because several different proteins have been detected in other studies. In order to understand the phosphorylation pathway that regulates hyperactivation, we established how to extract sperm protein completely and detected proteins that were phosphorylated during hyperactivation. Methods  Protein phosphorylation of hamster spermatozoa was detected by western blotting using antiphospho-amino acid monoclonal antibodies or the SELDI ProteinChip system with IMAC-Ga(III). Results  We detected 75 protein/peptide phosphoryations using the method established in the present study. Tyrosine phosphorylations occurred during hyperactivation. Serine or threonine phosphorylations occurred for 30 min. Furthermore, four of the serine or threonine phosphorations were phosphorylated by A-kinase. As for peptides, 15 peptides were dephosphorylated for 30 min. Other peptides were phosphorylated during hyperactivation. Conclusions  Because most of the proteins detected in the present study have been described previously, we could detect comprehensive protein phosphorylations. Moreover, we also detected many novel phosphopeptides. Although we did not understand the role of peptide, it was likely that motility was basically regulated by serine/threonine phosphorylations and hyperactivation was mainly regulated by tyrosine phosphorylations. (Reprod Med Biol 2006; 5: 123–135)     

TH1/TH2 and regulatory cytokines in adults with otitis media with effusion.

OBJECTIVE: Otitis media with effusion is one of the most common and intractable ear diseases. However, the role of Th1, Th2, and immunoregulatory cytokines on the pathogenesis of the disease in adult patients remains to be determined. The aim of this study is to disclose the cytokine expression in middle ear effusions (MEEs) in adults and to compare the profile on the basis of the presence of allergic rhinitis and the type of effusions. STUDY DESIGN: A prospective controlled clinical study. PATIENTS: MEEs were collected from 80 adult subjects. The concentration of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, and interferon (IFN)-gamma in MEEs were determined by using enzyme-linked immunosorbent assay. RESULTS: IL-2, IL-4, IL-5, IL-10, IL-12, and IFN-gamma in MEEs were detected in 60 (75.0%), 33 (41.3%), 42 (52.5%), 14 (17.5%), 80 (100%), and 66 (82.5%) samples, respectively. Among these cytokines, only the concentration of IL-4 in the allergic rhinitis-positive group was significantly higher than that in the allergic rhinitis-negative group. On the other hand, IL-2, IL-12, and IFN-gamma were detected, regardless of the presence of allergic rhinitis, and the concentration of these cytokines correlated with each other. The correlation between the concentration of IL-4 and IL-5 was also detected. In addition, both the incidence rate and the concentration of IL-10 in MEEs were significantly higher in the mucoid type compared with those in the serous type effusions. CONCLUSION: Regardless of allergic status, IL-12 may play a critical role in the pathogenesis of otitis media with effusion by affecting the production of IL-2 and IFN-gamma. In addition, IL-4 may have some impact on the immunologic condition in adults with allergic rhinitis. IL-10 potentially affects the viscosity of MEEs.     

Somatic mutations of epidermal growth factor receptor in colorectal carcinoma.

PURPOSE: Somatic mutations of the epidermal growth factor receptor (EGFR) gene may predict the sensitivity of non-small cell lung carcinoma to gefitinib. However, no mutations have been reported for colorectal carcinoma. We therefore analyzed EGFR mutations in colorectal adenocarcinomas by the combined use of laser microdissection and sequencing of genomic DNA. EXPERIMENTAL DESIGN: We examined 11 representative colorectal adenocarcinoma cell lines and 33 clinical samples of colorectal carcinoma. In the clinical cases, we carefully dissected only carcinoma cells from frozen sections by laser microdissection. After DNA extraction and PCR, we examined EGFR mutations by sequencing genomic DNA. RESULTS: None of 11 colorectal carcinoma cell lines exhibited somatic mutations, but 4 of 33 clinical tumors (12%) exhibited mutations in the EGFR kinase domain. This may be the first report of somatic mutations in colorectal adenocarcinoma. CONCLUSIONS: Our findings suggest that a distinct minority of colorectal adenocarcinomas exhibit somatic mutations of EGFR, and these tumors may be susceptible to gefitinib treatment.     

Overexpression of the aldo-keto reductase family protein AKR1B10 is highly correlated with smokers' non-small cell lung carcinomas.

PURPOSE: Squamous cell carcinoma (SCC) and adenocarcinoma of the lung are currently subject to similar treatment regimens despite distinct differences in histology and epidemiology. The aim of this study is to identify a molecular target with diagnostic and therapeutic values for SCC. EXPERIMENTAL DESIGN: Genes specifically up-regulated in SCC were explored through microarray analysis of 5 SCCs, 5 adenocarcinomas, 10 small cell lung carcinomas, 27 normal tissues, and 40 cancer cell lines. Clinical usefulness of these genes was subsequently examined mainly by immunohistochemical analysis. RESULTS: Seven genes, including aldo-keto reductase family 1, member B10 (AKR1B10), were identified as SCC-specific genes. AKR1B10 was further examined by immunohistochemical analysis of 101 non-small cell lung carcinomas (NSCLC) and its overexpression was observed in 27 of 32 (84.4%) SCCs and 19 of 65 (29.2%) adenocarcinomas. Multiple regression analysis showed that smoking was an independent variable responsible for AKR1B10 overexpression in NSCLCs (P < 0.01) and adenocarcinomas (P < 0.01). AKR1B10 staining was occasionally observed even in squamous metaplasia, a precancerous lesion of SCC. CONCLUSION: AKR1B10 was overexpressed in most cases with SCC, which is closely associated with smoking, and many adenocarcinoma cases of smokers. These results suggest that AKR1B10 is a potential diagnostic marker specific to smokers' NSCLCs and might be involved in tobacco-related carcinogenesis.     

An association between plasma levels of 8-isoprostane and alcohol drinking habits in Japanese volunteers]

Lipid peroxidation and oxidative stress may play a certain role in the pathogenesis of pressure-induced atherosclerosis, and alcohol related diseases. Recently, 8-isoprostane in biological fluids has been reported to be a reliable marker for lipid peroxidation and oxidative stress in vivo. In the present study, we developed an ELISA method for 8-isoprostane which has high sensitivity, intra- and inter-assay reproducibility and wide dynamic assay range. Using this method, we examined the effects of drinking and smoking habits on plasma levels of 8-isoprostane in healthy subjects. A total of 157 apparently healthy volunteers was assayed for plasma 8-isoprostane. Subjects were divided into three groups according to their alcohol consumption. Group I is non- or few-drinkers, Group II includes subjects who drink once or twice a week, and subjects of Group III intake 3 to 5 times a week or almost every day. In addition, the same population was divided into two groups, 96 non-smokers and 61 smokers. Plasma 8-isoprostane was extracted with ODS gel followed by NH2 Sep-Pak column. The 8-isoprostane fractions thus separated were assayed by a commercial ELISA kit (Cayman Chemical). The plasma 8-isoprostane was estimated to be 20.9 +/- 93 pg/ml in a total of 157 volunteers (83 male, 74 female). The plasma 8-isoprostane levels were elevated in the Group III (26.6 +/- 9.5 pg/ml) compared with Group I (20.3 +/- 6.1 pg/mL, p<0.0001) and Group II (20.9 +/- 5.7 pg/ml, p<0.001). Significant increase of the plasma 8-isoprostane was observed only in habitual drinkers of females, but not in those of males. On the other hand, no significant difference of the plasma 8-isoprostane levels were observed between non-smokers (21.5 +/- 7.3 pg/ml) and smokers (22.8 +/- 7.4 pg/ml, p>0.05). We suppose that plasma 8-isoprostane may increase in the habitual drinkers due to the oxidization stress induced by alcohol intake, and it may become a useful marker to estimate drinking habit     

Inhibition of autophagy by chloroquine makes chemotherapy in nasopharyngeal carcinoma more efficient

Objectives

A combination of platinum-based chemotherapy and radiotherapy is the standard treatment for nasopharyngeal carcinoma (NPC). However, the efficacy of chemotherapy has reached a plateau. Many autophagy studies suggest that autophagy can either promote or suppress to cancer progression. Thus, a role of autophagy in the acquisition of chemoradioresistance has recently been a notable event. Therefore, we examined the relationship between autophagy and chemotherapy in NPC.