Model for the drug-drug interaction responsible for CYP3A enzyme inhibition. I: evaluation of cynomolgus monkeys as surrogates for humans

1. Anti-human cytochrome P450 (CYP) 3A4 antiserum completely inhibited midazolam metabolism in monkey liver microsomes, suggesting that midazolam was mainly metabolized by CYP3A enzyme(s) in monkey liver microsomes. 2. Midazolam metabolism was also inhibited in vitro by typical chemical inhibitors of CYP3A, such as ketoconazole, erythromycin and diltiazem, and the apparent K(i) values for ketoconazole, erythromycin and diltiazem were 0.127, 94.2 and 29.6 microM, respectively. 3. CYP3A inhibitors increased plasma midazolam concentrations when midazolam and CYP3A inhibitors were co-administered orally. However, the pharmacokinetic parameters of midazolam were not changed by treatment with CYP3A inhibitors when midazolam was given intravenously. This suggests that CYP3A inhibitors modified the first-pass metabolism in the liver and/or intestine, but not systemic metabolism. 4. The drug-drug interaction responsible for CYP3A enzyme(s) inhibition was observed when midazolam and inhibitors were co-administrated orally. Therefore, it was concluded that monkeys given midazolam orally could be useful models for predicting drug-drug interactions in man based on CYP3A enzyme inhibition.

Effects of anoxia on serum immunoglobulin and albumin leakage through blood–brain barrier in mouse cerebellum as revealed by cryotechniques

The purpose of this study was to examine time-dependent topographical changes of leaking proteins from blood vessels in the mouse cerebellum to assess the effect of normal blood circulation on the blood-brain barrier (BBB). The distribution of leaking serum proteins was immunohistochemically examined by various cryotechniques including our "in vivo cryotechnique". The cryofixed cerebellar tissues were processed for the freeze-substitution method, and finally embedded in the common paraffin wax. Serial de-paraffinized sections were immunostained by anti-mouse immunoglobulin-G (IgG) or albumin antibody. By combination of the "in vivo cryotechnique", in which normal blood flow into the cerebellum was always kept in vivo, with the freeze-substitution method, serum IgG and albumin were clearly localized inside of cerebellar blood vessels. To examine abnormal leakage of blood vessels as a model of anoxia, some cerebellar tissues were partially removed from brains in the mouse skull and quickly frozen in the isopentane-propane within a minute. In such resected cerebellar tissues, serum IgG and albumin were diffusely immunostained in large areas around the blood capillaries, probably because of easy leakage of the serum components through the immediately changed BBB. To the contrary, no serum protein could be identified outside blood capillaries under living conditions of the anesthetized mice. The present combination method, both "in vivo cryotechnique" and freeze-substitution, for immunohistochemistry enabled us to examine the in vivo localization of serum components in mouse brains due to alteration of the BBB.

Global metabolic response of Escherichia coli to gnd or zwf gene-knockout, based on 13 C-labeling experiments and the measurement of enzyme activities

An integrated study on cell growth, enzyme activities and carbon flux redistribution was made to investigate how the central metabolism of Escherichia coli changes with the knockout of genes in the oxidative pentose phosphate pathway (PPP). Mutants deficient in glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were constructed by disrupting the zwf and gnd genes and were grown in minimal media with two different carbon sources, such as glucose or pyruvate. It was shown that the knockout of either gnd or zwf gene did not affect the cell growth rate significantly, but the cellular metabolism was changed. While the specific substrate uptake rate and the specific carbon dioxide evolution rate for either mutant grown on glucose were higher than those obtained for the parent strain, these two rates were markedly decreased in mutants grown on pyruvate. The measurement of enzyme activities implied a significant change in metabolism, when alternative pathways such as the Entner-Doudoroff pathway (EDP) and the malic enzyme pathway were activated in the gnd mutant grown on glucose. As compared with the parent strain, the activities of phosphoglucose isomerase were increased in mutants grown on glucose but decreased in mutants grown on pyruvate. The metabolic flux redistribution obtained based on 13C-labeling experiments further indicated that the direction of the flux through the non-oxidative PPP was reversed in response to the gene knockout. Moreover, the knockout of genes caused an increased flux through the tricarboxlic acid cycle in mutants grown on glucose but caused a decrease in the case of using pyruvate. There was also a negative correlation between the fluxes through malic enzyme and isocitrate dehydrogenase in the mutants; and a positive correlation was found between the fluxes through malic enzyme and phosphoenolpyruvate carboxylase.

No nephropathy in Type 2 diabetic patient with POEMS syndrome with an elevated plasma VEGF

Vascular endothelial growth factor (VEGF) is considered to have a role in the pathogenesis of diabetic retinopathy. Recent experimental observations that anti-VEGF neutralizing antibody fully abolished the hyperfiltration and the increase in urinary albumin excretion suggested the contribution of VEGF to the development of diabetic nephropathy, as well. Here, we present a case of POEMS (Crow-Fukase) syndrome with Type 2 diabetes, which was associated with elevated plasma VEGF level, but no sign of diabetic nephropathy. The findings obtained from this case did not support the hypothesis that VEGF may enhance the development of diabetic nephropathy.

Primary motor cortex stimulation within the central sulcus for treating deafferentation pain

Nine patients with post-stroke pain, six with brachial plexus injuries, two with phantom limb pain, one with spinal cord injury, and one with brain stem injury were treated with a modified motor cortex stimulation (MCS) protocol. Preoperative pharmacological tests were performed with phentolamine, lidocaine, ketamine, thiopental, morphine, and placebo. We placed a grid electrode in the subdural space to decide upon the best stimulation point for pain relief over a few weeks with the purpose of determining the placement of a Resume electrode. In five patients, Resumes were implanted in the interhemispheric fissure to reduce lower extremity pain. In five other patients, Resumes were placed within the central sulcus to stimulate area 4 and area 3b. In addition, electrodes were also placed on the surface of the precentral gyrus. Fourteen of the 19 patients showed pain reduction (6 excellent, 3 good, and 5 fair) using the MCS with our results indicating area 4 within the central sulcus to be the optimal stimulation point for pain relief. We speculate that conventional method may sometimes fail to stimulate area 4 and that focal stimulation of the primary motor cortex within the central sulcus may improve the efficacy of this treatment. Our pharmacological tests show that patients with ketamine sensitivity seem to be good candidates for MCS. Test stimulation with a subdural multi-grid electrode and Resumes in the cetral sulcus were helpful in locating the best stimulation point for pain relief.

Use of Bid-ribozymes to characterize and Bid-affiliated apoptotic pathway

Multiple cell and stimulus specific apoptosis pathways have been identified (1) revealing a complexity of molecular events involved. Tumor necrosis factor (TNF alpha) is known to activate mitochondria dependent or independent pathways for cell death. These pathways converge to activate effector caspases, caspases 3, 6 and 7 (2). The intermediate events including the substrates and effectors however are not clearly understood. In this report, we have employed ribozyme technology to elucidate some of these intermediate events. We show here that Bid, a pro-apoptotic facilitator that plays an important role in the mitochondrial pathway, can be targeted by Bid-specific ribozymes. MCF7 breast carcinoma cells stably transfected with expression plasmids encoding active (but not inactive or mock) Bid ribozymes showed delayed response to TNF alpha. This was accompanied by decreased activation of caspases 7 and 9, but not of caspase 8. The data assign caspase 9 as an upstream activator of caspase 7 in TNF alpha-induced Bid-mediated apoptosis.

A novel approach to selection of functional proteins

We present here a novel approach to connect phenotype and genotype in vitro by exploiting a strong interaction between RNA and protein. This strong interaction was used for the selection of functional proteins, such as dihydrofolate reductase (DHFR) and streptavidin, which were chosen as examples. The noncovalent but strong interaction should be useful as a novel tool for the future selection of functional proteins.

Effects of 3,3',4,4',5-pentachlorobiphenyl, a coplanar polychlorinated biphenyl congener, on cultured neonatal mouse testis

3,3',4,4',5-Pentachlorobiphenyl (PCB126), a congener with a planar configuration, has been established to have relatively strong toxicities similar to those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) via aryl hydrocarbon receptors. We investigated the effects of this coplanar PCB on mammalian early spermatogenesis and steroidogenesis in a mouse neonatal testicular organ culture system. Testes collected from newborn mice were subjected to organ culture in medium containing 0, 10, 100 or 1000 nM PCB126. Histochemical analysis revealed that the BrdU-labeling indices of both spermatogenic cells and Sertoli cells were unchanged in all testis specimens exposed to the coplanar PCB. CYP1A1 and steroidogenic enzymes (P450scc, P450c17, 3beta-HSD and 17beta-HSD) mRNA levels were determined by semiquantitative RT-PCR. The CYP1A1 mRNA level in cultured testis was significantly increased by PCB126 in a dose-dependent manner. Although mRNA levels of 3beta-HSD and 17beta-HSD were unchanged, the P450scc mRNA level was significantly down-regulated by PCB126 in a dose-dependent manner. In contrast, the P450c17 mRNA level was significantly higher in 1000 nM PCB126-exposed testis than in control testis. These results suggest that the coplanar PCB does not alter the proliferative activity of spermatogenic cells and Sertoli cells in neonatal testis, but that it directly affects the expression of steroidogenic enzyme genes.

Theoretical study on the excited states of psoralen compounds bonded to a thymine residue

Time-dependent density functional theory calculations have been performed for the excited states of psoralen, 5-methoxypsoralen, and 8-methoxypsoralen in systems and furan and pyrone monoadducts bonded to a thymine residue. The theoretical assignments to ultraviolet (UV) absorption spectra of isolated systems have been performed. The present calculations have clarified that the excitation energies of the first singlet excited (S1) state of monoadducts are blue-shifted compared with the isolated systems. It is shown that, in particular, the S1 excitation energy of the pyrone monoadduct is significantly blue-shifted and, therefore, the pyrone monoadduct is not excited by UV-A light (300-400 nm), which is used in the photochemotherapy.

Alkylphenol and bisphenol A levels in rubber products

Levels of p-t-butylphenol (PTBP), p-t-octylphenol (PTOP), p-nonylphenol (NP) and bisphenol A (BPA) in rubber products in food-contact use, infant-related use and other uses are reported. Of 60 rubber products tested, PTOP was found in three in a concentration range of 2.2-37 microgram g(-1), and NP in 15 in a concentration range of 2.6-513 microgram g(-1). PTBP and BPA were not found in any sample. PTOP and NP were not detected in any infant-related sample, regardless of the material type. In contrast, among the samples with food contact and with other uses, the percentages containing PTOP or NP were 33 and 43%, respectively. A migration test was performed on eight samples containing NP and used in food-contact environments. The migration level of NP from spatulas to n-heptane was 0.83-1.52 microgram ml(-1). The average migration rates to water, 20% ethanol and n-heptane were 0.03, 0.7 and 6.6%, respectively.

Plasma vascular endothelial growth factor in Japanese Type 2 diabetic patients with and without nephropathy

AIM

To determine whether plasma vascular endothelial growth factor (VEGF) level is elevated in Type 2 diabetic patients with an early stage of diabetic nephropathy.

METHODS

We studied 71 Japanese Type 2 diabetic patients with normal serum creatinine level (<100 micromol/l) (age 63.0 [60.3-65.6] years old, diabetes duration 15.6 [14.0-17.3] years, HbA1c 7.36% [7.06-7.66%], mean [95% confidence interval, CI]): normoalbuminuric patients (n=36); microalbuminuric patients (n=21); and proteinuric patients (n=14). Plasma VEGF concentration was measured by a quantitative sandwich enzyme immunoassay technique.

RESULTS

Plasma VEGF concentration was not related to the degree of albuminuria: normoalbuminuric patients (25 [13-95] ng/l, median [25th-75th percentile]); microalbuminuric patients (33 [15-120] ng/l); and proteinuric patients (54 [17-107] ng/l). Plasma VEGF level in patients with retinopathy (25 [15-95] ng/l, n=30) was not elevated as compared to those without retinopathy (53 [14-126] ng/l, n=34). Plasma VEGF tended to correlated negatively with diabetes duration (R's=-.217, P=.0690) and HbA1c (R's=-.221, P=.0647), whereas there was no correlation between plasma VEGF level and age, serum creatinine or urinary albumin to creatinine ratio (ACR) of the patients, respectively. Plasma VEGF level in the group of patients with HbA1c equal to or below the median (<7.2%) was significantly higher than that in the group of patients with HbA1c above the median (>7.2%) (P<.05).

CONCLUSIONS

The results suggested that Type 2 diabetic patients with microalbuminuria and those with retinopathy are not necessarily associated with an elevation of circulating plasma VEGF concentration. Plausible association between plasma VEGF level and glycemic control remains to be seen.

Imaging studies in patients with malignant melanoma in the female genital tract

The purpose of this study was to review magnetic resonance imaging (MRI) and pathologic features of primary malignant melanoma (melanoma) in the female genital tract. We retrospectively evaluated MRI in six women with melanoma of the genital tract. The signal intensity of the tumor on T1-weighted images (WI) was compared with the amount of melanin granules in hematoxylin-eosin stained sections of resected specimen. On T1WI, four melanomas showed a high signal intensity, one intermediate, and one low. The four melanomas with a high signal intensity on T1W1 were rich in melanin granules, while the one intermediate tumor had few granules. The other one was amelanotic. We believe that a high signal on T1WI is characteristic of primary melanotic melanoma of the female genital tract. Our findings suggest that it is strongly influenced by the presence of melanin granules.

Total plasma homocysteine is associated with hypertension in Type I diabetic patients

AIMS/HYPOTHESIS

Although hyperhomocysteinaemia and methylenetetrahydrofolate reductase gene polymorphism are accepted risk factors for cardiovascular disease, their association with micro angiopathy or blood pressure in diabetic patients is still being debated. This study explores the relation between plasma homocysteine concentrations, methylenetetrahydrofolate reductase gene polymorphism, hypertension, diabetic microvascular and macrovascular complications associated with kidney function.

METHODS

Vascular complications, hypertension, methylenetetrahydrofolate reductase genotype (RFLP with Hinf I digestion), and total plasma homocysteine (HPLC) were investigated in 389 well-characterized Type I (insulin-dependent) diabetic patients with normal (GFR> or=75 ml x min(-1) x (1.73 m(2))(-1); n=273), or impaired renal function (GFR <75 ml x min(-1) x (1.73 m(2))(-1); n=116).

RESULTS

Patients with microvascular and macrovascular complications showed higher total plasma homocysteine concentrations than those without complications. However, after the data for GFR (main determinant for plasma homocysteine) was adjusted we observed that plasma homocysteine concentrations greater than 8.6 micro mol/l in patients with normal GFR are not related to vascular complications, but to hypertension (8.6-11.3 micro mol/l: OR 1.9; >11.3 micro mol/l: OR 3.7). The risk for coronary heart disease (CHD) was also enhanced by a plasma homocysteine concentration greater than 11.3 micro mol/l (OR 5.9). Although the T allele was an independent determinant of plasma homocysteine, the methylenetetrahydrofolate reductase gene polymorphism was neither associated with diabetic vascular complications nor with hypertension.

CONCLUSION/INTERPRETATION

Increased plasma homocysteine concentrations but not the T allele per se, enhance the risk of hypertension and of CHD in Danish Type I diabetic patients with normal renal function.

An efficient synthesis of (±)-narwedine and (±)-galanthamine by an improved phenolic oxidative coupling

Old problems, new ideas! The biomimetic phenol coupling of norbelladine derivatives such as 1 (Bn = benzyl) to form galanthamine (2), a drug used in the treatment of Alzheimer's disease, has been greatly improved by the use of the hypervalent-iodine oxidation reagent phenyliodine(III) bis(trifluoroacetate) (PIFA).

Imaging studies in patients with malignant melanoma in the female genital tract

The purpose of this study was to review magnetic resonance imaging (MRI) and pathologic features of primary malignant melanoma (melanoma) in the female genital tract. We retrospectively evaluated MRI in six women with melanoma of the genital tract. The signal intensity of the tumor on T1-weighted images (WI) was compared with the amount of melanin granules in hematoxylin-eosin stained sections of resected specimen.

On T1WI, four melanomas showed a high signal intensity, one intermediate, and one low. The four melanomas with a high signal intensity on T1W1 were rich in melanin granules, while the one intermediate tumor had few granules. The other one was amelanotic. We believe that a high signal on T1WI is characteristic of primary melanotic melanoma of the female genital tract. Our findings suggest that it is strongly influenced by the presence of melanin granules.

[Surgical treatment of cardiovascular manifestations of Marfan syndrome]

The present study determines the effect of surgical treatment of cardiovascular manifestations of Marfan syndrome in 72 patients by 114 operations, during 34-year period. This therapy resulted in aortic root repair, aortic arch replacement, or both in 78, mitral valve repair in 9, descending thoracic aortic replacement in 14, thoracoabdominal aortic replacement in 10, and abdominal aortic replacement in 6, including total aortic replacement in 4 and nearly total aortic replacement in 4 patients. Fusiform aneurysms were present in the the ascending aorta in 37, the aortic arch in 2, the thoracoabdominal aorta in 2, and the abdominal aorta in 6 patients. Aortic dissection occurred in 40 (55.6%), including type A aortic dissection in 29 patients. Aortic root repair included separate valve-graft in 8, Bentall composite valve-graft in 25, composite valve-graft with button technique in 26, composite valve-graft with interposition graft technique in 10, and valve sparing procedure in 5 patients. The overall early (30-day) mortality was 7.9%. The early survival was 75% in separate valve-graft procedure and 99.2% in composite valve-graft procedure. Late coronary dehiscence did not occur in the patients with Bentall technique in which the reattachments of coronary ostia were performed in 2 layers, but occurred in 50% of patients with the coronary anastomoses in 1 layer. Aortic valve regurgitation relapsed in 2 of the 5 patients with valve sparing procedure. Event free rate for the patients with composite valve-graft using button technique was 81.1% at 10 years. There were 14 late deaths; dissection or rupture of the residual aorta, composite graft endocarditis and cardiac failure were the principle causes of late deaths. In conclusion, Marfan patients with cardiovascular diseases can undergo surgical treatment with a low operative risk and low morbidity. Although late endocarditis remains a serious problem, we believe that Marfan syndrome is a contraindication for valve sparing procedure. Because of the potential for late dissection or aneurysm in other areas of the aorta, patients with Marfan syndrome should have serial computed tomographic scans indefinitely.

An evaluation of chest X-ray screening for lung cancer in gunma prefecture, Japan: a population-based case-control study

In order to evaluate the efficacy of annual chest X-ray screening for lung cancer, a case-control study was conducted in Gunma Prefecture, Japan. Population-based annual lung cancer screening programmes have been conducted by the local government in Gunma Prefecture since the mid-1970s. A total of 121 case subjects, including 91 high-risk males and 30 non-high-risk females between the ages of 40 and 79 years who died of lung cancer from 1992 to 1997 were evaluated. A total of 536 controls (3-5 controls for each case) were matched to case subjects by gender, year of birth, address and smoking habits. Controls were selected from screening programme lists provided by the local governments. All case subjects were also included on these lists. The smoking-adjusted odds ratio (OR) of lung cancer death for those subjects screened within 12 months prior to diagnosis versus those not screened was 0.68 (95% confidence interval (CI): 0.44-1.05; P=0.084). When the analysis was conducted without matching case and control subjects by smoking habits, the OR was 0.79 (95% CI: 0.53-1.18). When stratified by histological type, the OR was 0.62 (95% CI: 0.31-1.24) for adenocarcinoma, and 1.01 (95% CI: 0.44-2.31) for squamous cell carcinoma. The results of this study suggest 20-30% of deaths attributable to lung cancer, especially adenocarcinoma, might be prevented by annual chest X-rays.

Ultrastructural study of mouse renal glomeruli under various hemodynamic conditions by an "in vivo cryotechnique"

Three-dimensional ultrastructure of mouse renal glomeruli under various hemodynamic conditions was studied by scanning electron microscopy with an "in vivo cryotechnique" followed by freeze-substitution. These results were also compared with those of conventionally fixed glomeruli at different perfusion pressures. Some kidneys of anesthetized mice were directly frozen in vivo under normal blood flow condition. Others were frozen in the same way after ligation of the lower abdominal aorta or their heart arrest. The frozen specimens were routinely freeze-substituted, freeze-dried and ion-sputtered for SEM. For another conventional fixation method, some kidneys were perfused with glutaraldehyde at pressures of 150 cm or 250 cm water, and other renal cortical tissues were routinely immersion-fixed with glutaraldehyde. In freeze-substituted specimens with the in vivo cryotechnique, interdigitating foot processes of podocytes exhibited smooth surface contours with less shrinkage and their surfaces were arranged more tightly than those seen by the conventional fixation method. In the anesthetized mice, filtration slits between the foot processes were found to be narrow after the heart arrest, but they were wide under the normal blood flow condition. After the aorta ligation, the filtration slits became wider and the foot processes were more elongated. The ultrastructure of capillary loops in functioning renal glomeruli were revealed to be dynamically changing in the living state, depending on various hemodynamic conditions.

Long-term effect on optic nerve of silicone oil tamponade in rabbits: histological and EDXA findings

PURPOSE

Side-effects after intravitreal use of silicone oil (SO) are not well defined and elucidated. The object of this study was to examine the influence and toxicity of SO on the optic nerve after vitrectomy with SO tamponade.

METHODS

We injected medical grade SO and emulsified SO into rabbit eyes after gas-mediated vitreous compression and examined the eyes by light microscopy (LM), transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDXA) (point analysis and area analysis) 6 months after injection. We compared the findings in the non-treated eyes and eyes with only gas-mediated vitreous compression with those in SO-injected eyes.

RESULTS

Vacuole-like structures were seen in the optic nerve posterior to the lamina cribrosa. In the group treated with only gas-mediated vitreous compression, the myelin structures were shown by TEM to be destroyed and replaced by glial tissue, while in groups injected with medical grade or emulsified SO severe destruction of the myelin sheath (myelinolysis) was observed. Silicone was identified at the electron-dense edges of the vacuoles by EDXA point analysis, but not in the vacuoles without electron-dense deposits. Dots of Si K alpha were not seen in the control groups, and dense dots were observed in SO-injected groups, by EDXA area analysis.

CONCLUSIONS

Some of the vacuoles might be artefacts caused by insufficient fixation or the operative procedure, but TEM showed almost no artefacts in the control optic nerve. Thus, most vacuoles may be SO storage sites. SO uptake into the optic nerve might play a role in the pathogenesis of optic nerve atrophy after SO injection.

[Wood creosote: a historical study and its preparation in combination with herbal drugs]

Two kinds of creosote have been found based on historical evidence of the medicinal uses and origins. One is wood creosote, and distillate of wood-tar containing guaiacol and creosol. The other type of creosote is coal-tar creosote, obtained from coal-tar, containing naphthalene and anthracene as the major constituents. Wood creosote was prepared for the first time in Germany in 1830 and was used for medicinal purposes. It had been listed officially in the German, American, and Japanese Pharmacopoeia as an antibacterial agent for the treatment of pulmonary tuberculosis, diarrhea, and external injury. In recent days, it has been deleted from the Pharmacopoeia in Western countries and not officially used for medicinal purposes. However, wood creosote is still been listed in the Japanese Pharmacopoeia and is used for the treatment of diarrhea. Since the interest of common people in herbal medicines and self-medication has been increasing, the use of wood creosote has also been modified in combination with some herbal drugs, "Seiro-gan" especially is quite popular in Japan as a self-medication for digestive trouble, including food poisoning or diarrhea.

Rice genomics: current status of genome sequencing

Since its establishment in 1991, the Rice Genome Research Program (RGP) has produced some basic tools for rice genome analysis, including a cDNA catalogue, a genetic linkage map and a yeast artificial chromosome (YAC)-based physical map. For the further development of rice genomics, RGP launched in 1998 an international collaborative project on rice genome sequencing. A P1-derived artificial chromosome (PAC)-based, sequence-ready physical map has been constructed using the PCR markers from cDNA sequences (expressed sequence tag [EST] markers). Selected PAC clones with 100-150 kb inserts from chromosomes 1 and 6 have been subjected to shotgun sequencing. The assembled genomic sequences, after predicting the gene-coding region, have been published both through a public database and through our website. As of January 2000, 1.9 Mb from 13 PAC clones were published. Future prospects for understanding rice genomic information at the nucleotide level are discussed.

Increased cholesteryl ester transfer protein and changes in lipid metabolism from initiating insulin therapy

Insulin therapy is often necessary for glycemic control, and its effect on plasma lipids is an important issue with respect to arteriosclerosis. Previous reports suggested that increased cholesteryl ester transfer protein (CETP) appeared in diabetic patients with hyperinsulinemia or given a lot of insulin is atherogenic. We investigated whether insulin always increases CETP and whether increased CETP by insulin is always atherogenic. In 40 patients the amount and activity of CETP were assessed before and 2 weeks after initiation of insulin therapy. After starting insulin, plasma concentrations of total cholesterol, triglycerides, LDL-cholesterol, and remnant lipoprotein cholesterol decreased. No change occurred in HDL-cholesterol. Starting insulin therapy increased the amount and activity of CEIP. No significant correlation was observed between changes in CETP and in lipids including HDL-cholesterol or apolipoprotein concentrations. This is the first prospective study to show increased CETP activity after initiation of insulin therapy. After initiating insulin, CETP increases without accompanying atherogenic changes in lipid metabolism. Based on the changes observed, CETP in itself does not have atherogenicity and the increase, but no excess, of CETP by appropriate insulin therapy cannot be atherogenic.

Association of the DD genotype and development of Japanese type 2 diabetic nephropathy

We determined the insertion/deletion (I/D) polymorphism of the angiotensin-coverting enzyme (ACE) gene in a multicenter trial of ethnically homogeneous Japanese type 2 diabetes mellitus (DM) patients. All patients (n = 748) were divided into 5 groups as follows: group I (normoalbuminuric patients), group II (microalbuminuric patients), group III (overt albuminuric patients with serum creatinine (s-Cr) levels of less than 1.2 mg/dl), group IV (overt albuminuric patients with s-Cr levels of more than 1.3 mg/dl but excluding hemodialysis patients), and group V (hemodialysis patients). We selected patients with a diabetic duration of more than 15 years in the mild stage (groups I and II), but placed no limits on those in the advanced and end-stages (groups III, IV and V). The frequency of the DD genotype was slightly higher in the advanced and end stages. The frequency of the DD genotype in the mild stage differed from that in the end stage (II/ID/DD 47.8%/41.0%/11.2% vs. 37.0 %/43.3%/19.7% p = 0.07, II + ID/DD 88.8%/11.2% vs. 80.3%/19.7%, p < 0.05). D allele frequency in the mild stage also differed from that in the end stage (I/D 68.3%/31.7% vs. 58.7%/41.3%, p < 0.02). The presence of the DD genotype increased the risk of end-stage renal disease (ESRD) more than that of the other genotypes (odds ratio ID/II = 1.37, 95% CI 0.82-2.27; DD/II = 2.27, 95% CI 1.12-4.61). It appears that the DD genotype is associated with progression of Japanese type 2 diabetic nephropathy.

Genomic structure of mouse copper chaperone, COX17

Coxl7p was first cloned as a cytoplasmic copper chaperone from yeast mutant and recent works suggested the existence of mammalian homologues. Previous report has shown that a gel filtration fraction of heart extract containing porcine Coxl7p peptide promoted the survival of NIH3T3 fibroblast cells. In the present study, we first cloned DNA fragments of the mouse COX17 gene. The mouse COX17 spans approximately 6kb and consists of three exons. It was mapped to the center of chromosome 16, using a radiation hybrid-mapping panel. The major transcription start site is 80 bp upstream of the ATG initiation codon as determined by rapid amplification of cDNA ends (5'-RACE) analysis. Two potential polyadenylation sites are 3233 and 3293 bp downstream of the termination codon, respectively. Transient transfection of reporter plasmids containing portions of the mouse COX17 5'-flanking region into AtT-20 and NIH3T3 cells allowed the localization of the essential promoter to a 0.8 kb region upstream of the transcription starting site. Furthermore, the transfected luciferase activity was much higher in AtT-20 than NIH3T3. According to sequence analysis of the approximately 0.8kb 5'-flanking region, GC rich segments including consensus sequences for binding of the transcription factor Sp1, but no TATA/CAAT boxes, exist in the region of the transcription start site. Besides the GC box, binding sites for NRF-1 and 2 known as specific transcription factors for COX subunits are also localized around the transcription starting site.

Hydration and molecular motions in synthetic phytanyl-chained glycolipid vesicle membranes

Proton permeation rates across membranes of a synthetic branch-chained glycolipid, 1,3-di-O-phytanyl-2-O-(beta-D-maltotriosyl)glycerol (Mal3(Phyt)2) as well as a branch-chained phospholipid, diphytanoylphosphatidylcholine (DPhPC) were lower than those of straight-chained lipids such as egg yolk phosphatidylcholine (EPC) by a factor of approximately 4 at pH 7.0 and 25 degrees C. To examine whether degrees of water penetration and molecular motions in Mal3(Phyt)2 membranes can account for the lower permeability, nanosecond time-resolved fluorescence spectroscopy was applied to various membranes of branch-chained lipids (Mal3(Phyt)2, DPhPC, and a tetraether lipid from an extremely thermoacidophilic archaeon Thermoplasma acidophilum), as well as straight-chained lipids (EPC, 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC), and digalactosyldiacylglycerol (DGDG)) using several fluorescent lipids. Degrees of hydration of glycolipids, Mal3(Phyt)2, and DGDG were lower than those of phospholipids, EPC, POPC, and DPhPC at the membrane-water interfaces. DPhPC showed the highest hydration among the lipids examined. Meanwhile, rotational and lateral diffusive motions of the fluorescent phospholipid in branch-chained lipid membranes were more restricted than those in straight-chained ones. The results suggest that the restricted motion of chain segments rather than the lower hydration accounts for the lower proton permeability of branch-chained lipid membranes.

Antisense expression of a rice sucrose transporter OsSUT1 in rice (Oryza sativa L.)

We analyzed the function of a rice sucrose transporter, OsSUT1, by using antisense rice. There was no difference between antisense and wild-type plants in carbohydrate content and photosynthetic ability of the flag leaves in the vegetative growth stage, suggesting that OsSUT1 may not play an important role in carbon metabolism, at least in these materials.

Purification of docosahexaenoic acid ethyl ester using a silver-ion-immobilized porous hollow-fiber membrane module

Docosahexaenoic acid ethyl ester (DHA-Et) was purified by adsorption on Ag-ion-immobilized membranes via selective interaction between silver ion and carbon-carbon double bonds of DHA-Et. Silver ions were immobilized onto sulfonic-acid-group-containing porous hollow-fiber membranes at an Ag ion density of 1.4 mol/kg of membrane, and 30 membranes were housed in one module (inner diameter = 18 mm and effective length = 80 mm). The adsorption isotherms of DHA-Et in various organic solvents revealed that DHA-Et was adsorbed on the immobilized Ag ions with a DHA-Et/Ag ion molar binding ratio of 1/5 in methanol, and that acetonitrile was the solvent of choice for the elution of the adsorbed DHA-Et. Permeation of bonito oil ethyl ester solution in methanol through the Ag-ion-immobilized hollow-fiber membrane module demonstrated that the displacement adsorption of other lower unsaturated fatty-acid ethyl esters by DHA-Et proceeded along the membrane thickness. The purity of DHA-Et was improved to 99 wt % by permeating first bonito oil ethyl ester containing 95 wt % DHA-Et and then acetonitrile through the module.

Dynamin GTPase domain mutants block endocytic vesicle formation at morphologically distinct stages

Abundant evidence has shown that the GTPase dynamin is required for receptor-mediated endocytosis, but its exact role in endocytic clathrin-coated vesicle formation remains to be established. Whereas dynamin GTPase domain mutants that are defective in GTP binding and hydrolysis are potent dominant-negative inhibitors of receptor-mediated endocytosis, overexpression of dynamin GTPase effector domain (GED) mutants that are selectively defective in assembly-stimulated GTPase-activating protein activity can stimulate the formation of constricted coated pits and receptor-mediated endocytosis. These apparently conflicting results suggest that a complex relationship exists between dynamin's GTPase cycle of binding and hydrolysis and its role in endocytic coated vesicle formation. We sought to explore this complex relationship by generating dynamin GTPase mutants predicted to be defective at distinct stages of its GTPase cycle and examining the structural intermediates that accumulate in cells overexpressing these mutants. We report that the effects of nucleotide-binding domain mutants on dynamin's GTPase cycle in vitro are not as predicted by comparison to other GTPase superfamily members. Specifically, GTP and GDP association was destabilized for each of the GTPase domain mutants we analyzed. Nonetheless, we find that overexpression of dynamin mutants with subtle differences in their GTPase properties can lead to the accumulation of distinct intermediates in endocytic coated vesicle formation.

Structure and expression of the Ah receptor repressor gene

The aryl hydrocarbon receptor (AhR) repressor (AhRR) gene has been isolated and characterized from a mouse genomic library. The gene is distributed as 11 exons in a total length of about 60 kilobase pairs. Fluorescence in situ hybridization analysis has shown that the AhRR gene is located at mouse chromosome 13C2, at rat chromosome 1p11.2, and at human chromosome 5p15.3. The AhRR gene has a TATA-less promoter and several transcription start sites. In addition, putative regulatory DNA sequences such as xenobiotic responsive element (XRE), GC box, and NF-kappaB-binding sites have been identified in the 5'-upstream region of the AhRR gene. Transient transfection analyses of HeLa cells with reporter genes that contain deletions and point mutations in the AhRR promoter revealed that all three XREs mediated the inducible expression of the AhRR gene by 3-methylcholanthrene treatment, and furthermore, GC box sequences were indispensable for a high level of inducible expression and for constitutive expression. Moreover, by using gel mobility shift assays we were able to show that the AhR/Arnt heterodimer binds to the XREs with very low affinity, which is due to three varied nucleotides outside the XRE core sequence. We have also shown that Sp1 and Sp3 can bind to the GC boxes. Finally, both transient transfection analysis and gel mobility shift assay revealed that the AhRR gene is up-regulated by a p65/p50 heterodimer that binds to the NF-kappaB site when the cells has been exposed to 12-O-tetradecanoylphorbol-13-acetate, and this inducible expression was further enhanced by cotreatment of 12-O-tetradecanoylphorbol-13-acetate and 3-methylcholanthrene.

Bactericidal/permeability-increasing protein promotes complement activation for neutrophil-mediated phagocytosis on bacterial surface

The neutrophil bactericidal/permeability-increasing protein (BPI) has both bactericidal and lipopolysaccharide-neutralizing activities. The present study suggests that BPI also plays an important role in phagocytosis of Escherichia coli by neutrophils through promotion of complement activation on the bacterial surface. Flow cytometric analysis indicated that fluorescein-labelled E. coli treated with BPI were phagocytosed in the presence of serum at two- to five-fold higher levels than phagocytosis of the bacteria without the treatment. In contrast, phagocytosis of the fluoresceined bacteria with or without treatment by BPI did not occur at all in the absence of serum. The phagocytosis stimulated by BPI and serum was dose-dependent. The effect of BPI on phagocytosis in the presence of serum was not observed on Gram-positive bacteria (Staphylococcus aureus). Interestingly, the complement C3b/iC3b fragments were deposited onto the bacterial surface also as a function of the BPI concentration under conditions similar to those for phagocytosis. Furthermore, the BPI-promoted phagocytosis was blocked completely by anti-C3 F(ab')(2) and partially by anti-complement receptor (CR) type 1 and/or anti-CR type 3. These findings suggest that BPI accelerates complement activation to opsonize bacteria with complement-derived fragments, leading to stimulation of phagocytosis by neutrophils via CR(s).

Identification of a novel human ankyrin-repeated protein homologous to CARP

We cloned a novel ankyrin repeat protein, Arpp, by immunoscreening a cDNA library constructed from a human esophageal carcinoma cell line, TE1, with an antibody directed to a hypothetical protein encoded by antisense p53 mRNA. Arpp protein is composed of 333 amino acids and contains four ankyrin-like repeat motifs in the middle portion of the protein, a PEST-like sequence and a lysine-rich sequence similar to a nuclear localization signal in the N-terminal region, and a proline-rich region containing consensus phosphorylation sites in the C-terminal region. Protein sequence analysis revealed that Arpp is homologous (52.7% identity) to Carp which is shown to be involved in the regulation of the transcription of the cardiac ventricular myosin light chain 2 gene. Arpp mRNA was found to be expressed in normal skeletal and cardiac muscle. Interestingly, Arpp expression was detectable in bilateral ventricles, but undetectable in bilateral atria and large vessels, suggesting that Arpp may play a specific function in cardiac ventricles as well as skeletal muscles.

cDNA cloning and functional analysis of ascidian sperm proacrosin

cDNA cloning and functional analysis of proacrosin from the ascidian Halocynthia roretzi were undertaken. The isolated cDNA of the ascidian preproacrosin consists of 2367 nucleotides, and an open reading frame encodes 505 amino acids, which corresponds to the molecular mass of 55,003 Da. The mRNA of proacrosin was found to be specifically expressed in the gonad by Northern blotting and in the spermatocytes or spermatids by in situ hybridization. The amino acid sequences around His(76), Asp(132), and Ser(227), which make up a catalytic triad, showed high homology to those of the trypsin family. Ascidian acrosin has paired basic residues (Lys(56)-His(57)) in the N-terminal region, which is one of the most characteristic features of mammalian acrosin. This region seems to play a key role in the binding of (pro)acrosin to the vitelline coat, because the peptide containing the paired basic residues, but not the peptide substituted with Ala, was capable of binding to the vitelline coat. Unlike mammalian proacrosin, ascidian proacrosin contains two CUB domains in the C-terminal region, in which CUB domain 1 seems to be involved in its binding to the vitelline coat. Four components of the vitelline coat that are capable of binding to CUB domain 1 in proacrosin were identified. In response to sperm activation, acrosin was released from sperm into the surrounding seawater, suggesting that ascidian acrosin plays a key role in sperm penetration through the coat. These results indicate that ascidian sperm contains a mammalian acrosin homologue, a multi-functional protein working in fertilization.

Cervical fracture of the anterior and posterior elements without evidence of neurological deficit. A report of three cases

We present three cases of cervical spinal fracture, involving two columns without an obvious neurological deficit. Usually if two of three columns are fractured, the injury is considered unstable structurally and clinically. Fortunately our cases did not involve sensory or motor impairment because of an enlargement of the spinal canal.

Clathrin-dependent and clathrin-independent endocytosis are differentially sensitive to insertion of poly (ethylene glycol)-derivatized cholesterol in the plasma membrane

We examined the effect of a cholesterol derivative, poly (ethylene glycol) cholesteryl ether on the structure/function of clathrin-coated pits and caveolae. Addition of the compound to cultured cells induced progressive smoothening of the surface. Markedly, when the incorporated amount exceeded 10% equivalent of the surface area, fluid pinocytosis, but not endocytosis of transferrin, became inhibited in K562 cells. In A431 cells, both clathrin-independent fluid phase uptake and the internalization of fluorescent cholera-toxin B through caveolae were inhibited with concomitant flattening of caveolae. In contrast, clathrin-mediated internalization of transferrin was not affected until the incorporated poly (ethylene glycol) cholesteryl ether exceeded 20% equivalent of the plasma membrane surface area, at which point opened clathrin-coated pits accumulated. The cells were ruptured upon further addition of poly (ethylene glycol) cholesteryl ether. We propose that the primary reason for the differential effect of poly (ethylene glycol) cholesteryl ether is that the bulk membrane phase and caveolae are both more elastic than the rigid clathrin-coated pits. We analyzed the results with the current mechanical model (Rauch and Farge, Biophys J 2000;78:3036-3047) and suggest here that the functional clathrin-lattice is much stiffer than typical phospholipid bilayers.

Magnetic resonance imaging findings and postoperative neurologic dysfunction in elderly patients undergoing coronary artery bypass grafting

BACKGROUND

Small cerebral infarctions are common in elderly patients, but the association between the magnetic resonance imaging finding and neurologic dysfunction after coronary artery bypass grafting has not been evaluated.

METHODS

We determined, prospectively, whether varying degrees of abnormal findings on magnetic resonance images of the brain increased the incidence of preoperative cognitive decline, postoperative neuropsychological dysfunction, and stroke in 421 elderly patients (> or = 60 years) undergoing coronary artery bypass grafting.

RESULTS

Control patients (almost normal or leukoaraiosis, n = 212) had rates of postoperative neuropsychological dysfunction (7%) and stroke (1.4%); the small infarctions group (some small infarctions, n = 126) had rates of 13% and 5.6%, respectively; whereas patients with multiple infarctions (multiple small infarctions or broad infarctions, n = 83) had rates of 20% and 8.4%, respectively (p = 0.004, p = 0.013). In the group with multiple infarctions, 49 patients (59%) were asymptomatic and 21 patients (25%) had cognitive decline. Stepwise logistic regression analysis demonstrated that the significant predictors of multiple small infarctions or large infarctions were history of cerebrovascular disease, renal insufficiency, cognitive decline, and cerebral arteriosclerosis.

CONCLUSIONS

Multiple infarctions significantly increase the risk of neurologic dysfunction after coronary artery bypass grafting. Routine screening for preoperative cognitive decline should be performed to detect underlying ischemic cerebral disease in elderly patients.

Specific detection of circulating tumor cells by reverse transcriptase-polymerase chain reaction of a beta-casein-like protein, preferentially expressed in malignant neoplasms

Beta-casein-like protein (BCLP) is a putative protein on cervical cancer and exhibits immunological characteristics similar to those of bovine beta-casein. We evaluated if BCLP mRNA detection in the blood is useful in gynecologic malignancies. We examined 30 patients with uterine cancer, nine cultured cancer cell lines and 26 healthy women volunteers. From these study populations and samples, total RNA was obtained. Reverse transcriptase-PCR (RT-PCR) of BCLP was performed on each sample. Eighteen (60.0%) patients and 4 (15.4%) volunteers were positive for BCLP mRNA. The RT-PCR reached sensitivity and specificity of 60.0% and 84.6%, respectively. Of eight patients having diagnosed recurrence, 7 (87.5%) were positive for BCLP mRNA. In patients with recurrence, sensitivity and specificity were 87.5% and 50%, respectively. The expression of mRNA showed a correlation with recurrence, but no correlation with metastasis or histological type. BCLP was specifically expressed in cancer cells and might be an aid in clinical diagnosis.

Cloning and characterization of a tumor-associated antigen, beta-casein-like protein

Monoclonal antibody (MAb) 1C5 reacts with 87% of uterine cervical adenocarcinoma and bovine beta -casein, but not with squamous cell carcinoma. To clarify the characteristics of the antigen (beta-casein-like protein; BCLP) recognized by MAb 1C5, molecular cloning was performed using 5' rapid amplification of the cDNA ends (5' RACE) and the oligo-capping method. The protein predicted from the cDNA consisting of 937 nucleotides comprises 222 amino acids. The BCLP gene and deduced amino acid sequences were novel and showed no similarity to known cancer-associated genes in the database. Northern blot analysis showed that a 1.1 kb transcript was ubiquitously expressed in cancer cell lines and was predominantly expressed in uterine cervical adenocarcinoma. To clarify the function of BCLP, BCLP cDNA was transfected into L929 cells, resulting in a significant increase in cell area, a downregulation of cell growth rate and a decrease in cell attachment. We conclude that BCLP might be associated with cell morphology and a regulation of growth pattern of tumor.

Anionic sites in articular cartilage revealed by polyethyleneimine staining

Articular cartilage is a unique tissue that contains neither blood vessels nor nerves, and that performs mechanical loading during joint movement. These properties are endowed by abundant glycosaminoglycans (GAGs), which are capable of retaining water-soluble substances. The GAGs attach to core proteins and form proteoglycans. Although many studies have focused on proteoglycans and collagen fibrils in cartilage, little is known about the nature of the negative charge of GAGs. Recently, we investigated this subject using a cationic dye, polyethyleneimine (PEI), with several different techniques such as pre-embedding, post-embedding, and quick-freezing and deep-etching methods. In addition, we investigated whether the anionic charge is altered at low pH, using PEI and cationic colloidal gold (CCG) labeling. The shapes of PEI-positive structures revealed by the pre-embedding method varied at different pHs. Three-dimensional analysis using the quick-freezing and deep-etching method demonstrated that meshwork structures composed of fine filaments were decorated with tiny PEI granules. Additionally, the meshwork structure was broken down after chondroitinase ABC digestion. These data indicate that the large PEI deposits observed in pre-embedding preparations are, at least in part, artificial images, and that the meshwork structure consists of chondroitin sulfate-retaining anionic sites. Low pH conditions changed PEI or CCG labeling patterns, showing that negative charges of GAGs in articular cartilage are altered under environmental pH conditions. These findings demonstrate that binding capacities of anionic sites to water-soluble or ionic substances are greatly affected by pH alterations without actually decreasing the number of anionic sites. Therefore, to understand cartilage dynamics and the pathogenesis of joint diseases in greater detail, alterations of anionic charge during mechanical loading or under pathological conditions should be examined in future studies.