Effects of Simvastatin on RBL-2H3 Cell Degranulation

Hypercholesterolemia is a major complication of arteriosclerosis. Mast cells in arteriosclerosis plaques induce inflammatory reactions and promote arterial sclerosis. In this study, we evaluated the pharmacological effects of simvastatin (SV)-3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors on the degranulation of rat basophilic leukemia (RBL)-2H3 cells, which are commonly used as mast cell models. SV significantly decreased the degranulation induced by three types of stimulation: antigen antibody reaction (Ag-Ab), thapsigargin (Tg) serosal endoplasmic reticulum calcium ATPase (SERCA) inhibitor, and A23187 calcium ionophore. SV had a stronger inhibitory effect on degranulation induced by Ag-Ab stimulation than the other two stimulations. However, SV did not inhibit increase of intracellular Ca²⁺ concentrations. Mevalonate or geranylgeraniol co-treatment with SV completely prevented the inhibitory effect of SV on the degranulation induced by these stimulations. Immunoblotting results showed that SV inhibited protein kinase C (PKC) delta translocation induced by Ag-Ab but not by Tg or A23187. SV induced a reduction in active Rac1, and actin filament rearrangement. In conclusion, SV inhibits RBL-2H3 cell degranulation by inhibiting downstream signaling pathways, including the sequential degranulation pathway. These inhibitory effects were completely reversed by the addition of geranylgeraniol and might be induced by changes in the translocation of the small guanosine 5'-triphosphatase (GTPase) families Rab and Rho, which are related to vesicular transport PKC delta translocation and actin filament formation, respectively. These changes are caused by the inhibition of HMG-CoA reductase by SV following the synthesis of geranylgeranyl pyrophosphates, which play important roles in the activation of small GTPases, Rab.

[Implementation and Evaluation of Genetic Testing Seminars about Lifestyle-related Disease Prevention in Pharmacy Insurance-The Need for Cooperation between the Pharmacy and the University in Genetic Testing]

 A seminar titled "Implementation and evaluation of genetic testing of lifestyle-related disease genes" was held for pharmacists, medical clerks, and clerks of pharmacy insurance, with the aim of holding seminars led by pharmacists for the general public (including patients) in the future. The subject of the seminar was single nucleotide polymorphisms in obesity-related genes and alcohol metabolism-related genes. The purpose of the seminar was to contribute to the prevention of lifestyle-related diseases of the general public. We evaluated it by administering a questionnaire to the participants before and after the seminar. After the seminar, 55% of pharmacists answered that they would like to or would strongly like to participate in genetic testing (for lifestyle-related diseases and drug metabolism-related genes) of the general public. However, some participants did not wish to do so. A customer satisfaction (CS) analysis found that this was mainly because they did not want to know the results of genetic testing of others, which they felt should be private. Most (82%) of the pharmacists answered that assistance and advice was "very necessary" or "necessary" in the participation of genetic testing. These findings show that collaboration between pharmacies and universities will be important for future seminars to the general public.

Mechanisms of the action of adenine on anti-allergic effects in mast cells

Introduction

Mast cells play an important role in allergic responses.

Methods

We herein demonstrated the mechanisms of inhibitory effect of adenine on IgE/antigen‐induced degranulation and TNF‐α release in mast cells.

Results

We found that these effects were dependent on the amino group of adenine because purine only weakly inhibited degranulation. Adenine also inhibited Ca²⁺ ionophore‐ and thapsigargin‐induced degranulation, however, this inhibitory effect was weaker than that of the antigen. Therefore, the inhibitory effects of adenine on degranulation may be mediated before as well as after the Ca²⁺ raise under the antigen stimulus. Adenine inhibited antigen‐induced Syk and the subsequent induction of AKT and ERK activation under FcϵRI‐mediated signal. Adenine also attenuated antigen‐induced increase in Ca²⁺. Furthermore, adenine inhibited IgE/antigen‐induced IKKα/β activation, which is involved in degranulation. Finally, adenine protected mice against anaphylactic allergic responses in vivo.

Conclusions

The present study revealed a key role of adenine in the attenuation of allergic responses through the inhibition of Syk‐mediated signal transduction and IKK‐mediated degranulation.

Hyperparathyroidism — Comparison of Flash Imaging with Spin ECHO MR Imaging

MR images of the neck were prospectively studied in 19 patients with hyperparathyroidism. Fast low angle shot (FLASH) sequence was performed in addition to T1- and T2-weighted spin echo (SE) sequences. FLASH images were obtained with 320/12/20° (TR/TE/flip angle) using presaturation technique. TE of 12 ms was chosen to eliminate high signal of fat tissue. In the evaluation of detectability, a combination of T1-weighted SE and FLASH images (T1WI + FLASH) was compared with a combination of T1- and T2-weighted SE images (T1WI + T2WI). MR imaging correctly depicted 20 of 30 abnormal glands on both T1WI + FLASH and T1WI + T2WI. FLASH imaging effectively eliminated high signal of fat tissue. Nineteen abnormal glands demonstrated higher signal than surrounding tissues on FLASH images, whereas 12 glands were high-intense on T2-weighted SE images. We conclude that FLASH imaging provides improved tissue contrast and anatomic delineation and, thus, may replace T2-weighted SE imaging in the neck.

[Implementation and Evaluation of Genetic Testing Seminars on Lifestyle-related Disease Prevention for Pharmacy Students]

The field of pharmacotherapy has advanced to use molecular targeted agents, and pharmacists are now encouraged to focus on pharmacogenomics. A seminar titled "Implementation and evaluation of genetic testing of lifestyle-related disease genes" was presented to students at the Faculty of Pharmaceutical Sciences, Hiroshima University, describing the pharmacogenomic role of single nucleotide polymorphisms in obesity-related genes and alcohol metabolism-related genes. The seminar topic was selected first because pharmaceutical students were already familiar with some of the content, and secondly because we believe that pharmacists should be informed about the prevention of lifestyle-related diseases using genetic testing. We evaluated the usefulness of this seminar by administering a questionnaire before and after the seminar to participating students. Several points requiring improvement were identified, although 82% of students stated that the seminar was "very useful" or "useful". We conclude that this educational seminar was useful to students of pharmaceutical sciences.

Characteristic oscillatory motion of a camphor boat sensitive to physicochemical environment

A self-propelled camphor boat on water was investigated from the viewpoint of characteristic features of motion and mode-bifurcation depending on the diffusion length of camphor molecules. When a camphor disk was connected to the bottom of a larger plastic plate and then was placed on water, either oscillatory motion (repetition between rest and motion) or continuous motion was observed. In this paper, we report the novel features of this motion and mode-bifurcation as a function of the diffusion length of camphor molecules, e.g., multiple accelerations during oscillation, period-2 or irregular oscillatory motion, and reciprocating oscillation. These characteristic motion and mode-bifurcation are discussed in relation to the diffusion length of camphor molecules under the camphor boat and the development of camphor molecules from the camphor boat on water.

Expression of Forkhead box P3 in tumour cells causes immunoregulatory function of signet ring cell carcinoma of the stomach

Background:

It was recently reported that the transcription factor Forkhead box P3 (FoxP3) is expressed not only in regulatory T cells (Tregs) but also in cancer cells. The aim of this study was to clarify the clinical significance of FoxP3 expression in gastric carcinoma.

Methods:

We performed immunohistochemical staining of FoxP3 to examine the association of FoxP3 expression with clinicopathological features of 194 patients with gastric cancer who underwent surgical resection from 2000 to 2010. We also investigated the immunosuppressive function of FoxP3 using gastric cancer cell lines.

Results:

Immunohistochemical staining indicated FoxP3-positive cells within tumour tissue including both Tregs and tumour cells. Forkhead box P3-positive tumour cells were observed in 79.3% of signet ring cell carcinoma patients, and the expression of FoxP3 showed a significant correlation with lymph node metastasis. We showed that transforming growth factor-β augmented FoxP3 mRNA expression in cell lines derived from signet ring cell carcinoma. Indoleamine-2,3-dioxygenase and galectin-1, key effectors of Treg-mediated immunosuppression, were downregulated by FoxP3 knockdown.

Conclusion:

Our findings suggested that FoxP3 expression by tumour cells might have important roles in immune escape of gastric carcinoma, and be associated with the malignant potential of scirrhous gastric carcinoma.

Brain lesions induced by experimental intranasal infection of Japanese encephalitis virus in piglets

Non-suppurative encephalitis was experimentally induced in three-week-old piglets by a single intranasal inoculation of Japanese encephalitis virus (JEV) isolated from field pigs. The lesions consisted of glial cell aggregates and perivascular cuffing throughout the olfactory tract and pyriform cortex. JEV antigens were detected in the cytoplasm and neuronal processes of small nerve cells in the granule cell layer of the olfactory bulb, in the neuronal processes of the olfactory tract and in the cytoplasm of neurons in the pyriform cortex. The distribution of the antigens corresponded closely with the distribution of brain lesions. These findings suggest that JEV may enter the brain by the olfactory pathway in addition to via haematogenous spread in piglets.

Evaluation of unexpected positive results from a commercial ELISA for antibodies to PRRSV

Unexpected positive results from the widely used IDEXX ELISA for the detection of antibodies to porcine reproductive and respiratory syndrome virus (PRRSV) may confound investigations of the disease. Supplementing the ELISA with blocking agents and the use of IgG purified from serum samples had no effect on the unexpected positive results, suggesting that they were due to an antibody-antigen reaction. Simple competitive and blocking ELISAs were developed by modifying the IDEXX ELISA, and they and an indirect fluorescent antibody test (IFAT) were used to examine PRRSV antibodies in 33 antibody-negative, 88 antibody-positive and 73 unexpectedly positive sera. All the unexpectedly positive sera were negative by IFAT, and 89.0 per cent were negative by both the competitive and blocking ELISAs. The competitive ELISA (97.7 per cent) and the blocking ELISA (96.5 per cent) detected more positive sera than the IFAT (90.9 per cent). These results show that both ELISAs are capable of distinguishing positive and unexpectedly positive sera, and suggest that most of the unexpected positive signals are false-positives.

Endoplasmic reticulum stress induces leptin resistance

Leptin is an important circulating signal for inhibiting food intake and body weight gain. In recent years, "leptin resistance" has been considered to be one of the main causes of obesity. However, the detailed mechanisms of leptin resistance are poorly understood. Increasing evidence has suggested that stress signals, which impair endoplasmic reticulum (ER) function, lead to an accumulation of unfolded proteins, which results in ER stress. In the present study, we hypothesized that ER stress is involved in leptin resistance. Tunicamycin, thapsigargin, or brefeldin A was used to induce ER stress. The activation status of leptin signals was measured by Western blotting analysis using a phospho-(Tyr705) signal transducer and activator of transcription 3 (STAT3) antibody. We observed that ER stress markedly inhibited leptin-induced STAT3 phosphorylation. In contrast, ER stress did not affect leptin-induced c-Jun NH(2)-terminal kinase activation. These results suggest that ER stress induces leptin resistance. ER stress-induced leptin resistance was mediated through protein tyrosine phosphatase 1B but not through suppressors of cytokine signaling 3. It is noteworthy that a chemical chaperone, which could improve the protein-folding capacity, reversed ER stress-induced leptin resistance. Moreover, homocysteine, which induces ER stress, caused leptin resistance both in vitro and in vivo. Together, these findings suggest that the pathological mechanism of leptin resistance is derived from ER stress.

Changes in the myosin heavy chain 2a and 2b isoforms of the anterior belly of the digastric muscle before and after weaning in mice

During the process of growth and development, the digastric muscle is subjected to marked functional changes, including the change from suckling to mastication. In particular, because the anterior belly of the digastric muscle, which is one of the suprahyoid muscles, plays an important role in mastication. Therefore, this muscle seems to undergo a marked functional change before and after weaning. However, the details remain unknown. Here, to clarify the changes in the muscle fibre characteristics of the anterior belly of the digastric muscle before and after weaning, we examined myosin heavy chain isoforms at the protein (immunohistochemistry) and mRNA (transcription) levels. As a control, the changes in the muscle fibre characteristics of the sternohyoid muscle, which is anatomically aligned in the same direction as the anterior belly of the digastric muscle, were analyzed. The results showed that, in the anterior belly of the digastric muscle that is involved in mandibular movements in mice, the ratio of a fast-contraction isoform with strong contractile force increased after weaning. We believe that this occurred in response to a functional change from suckling to mastication. On the other hand, there was little change in the composition of sternohyoid muscle.

Association of single nucleotide polymorphisms in endothelin family genes with the progression of atherosclerosis in patients with essential hypertension

Endothelin-1 (ET-1) is a potent vasoconstrictive peptide and its activity is mediated by the receptors ET type A (EDNRA) and ET type B (EDNRB). Although ET-1 is thought to play an important role in the development of atherosclerosis, it remains unclear whether polymorphisms of ET-1 family genes, including the ET-1 gene (EDN1), EDNRA, EDNRB and the genes for endothelin converting enzymes 1 and 2 (ECE1 and ECE2), are associated with the progression of atherosclerosis. We investigated the relationship between 11 single nucleotide polymorphisms (SNPs) of ET-1 family genes (including three in EDN1, one in EDNRA, two in EDNRB, four in ECE1 and one in ECE2) and atherosclerotic changes assessed using pulse wave velocity (PWV) and carotid ultrasonography in 630 patients with essential hypertension (EHT). In male subjects, we found significant differences in brachial-ankle PWV (baPWV) in additive and recessive models in EDNRB-rs5351 after Bonferroni correction. Also in male subjects, there were significant differences in mean intima-media thickness (IMT) in additive and recessive models in EDNRA-rs5333 after Bonferroni correction. We found no significant correlation between any SNPs in the ET family genes and baPWV, IMT and Plaque score (PS) in female subjects. Furthermore, after multiple logistic regression analysis, only EDNRB-rs5351 indicated as an independent risk of atherosclerosis in male hypertensive subjects. Of the endothelin-related genes, EDNRB-rs5351 was the most susceptible SNP associated with atherosclerosis in male hypertensives, and the genetic background may be involved in the progression of atherosclerosis in EHT patients.

Optic nerve hyperintensity on T2-weighted images among patients with pituitary macroadenoma: correlation with visual impairment

PURPOSE

Visual acuity (VA) disturbance other than field defect is important in evaluating patients with pituitary macroadenoma. The purpose of this study was to evaluate MR imaging appearances of optic nerves in patients with pituitary macroadenoma and to ascertain whether visual impairment was correlated with abnormality in optic nerve signal intensity.

PATIENTS AND METHODS

Twenty-seven patients with pituitary macroadenoma were examined. Optic nerves were evaluated on T2-weighted images and correlations of signal intensity abnormality with VA disturbance, visual field disturbance, degree of optic chiasm compression, pathologic findings of surgical specimen, and disease duration were statistically analyzed. Correlations between recovery of VA after treatment and the above-mentioned factors were also determined.

RESULTS

Coronal T2-weighted images demonstrated unilateral optic nerve hyperintensity lesions in 9 patients. Bilateral signal intensity abnormality of the optic nerve was seen in 5 patients. Signal intensity abnormality of the optic nerve was seen at the site of compression and in the ventral side of the tumor. These patients did not demonstrate signal intensity abnormality posterior to the tumor. Presence of such signal intensity abnormalities was correlated with the degree of optic chiasmal compression and with VA disturbance. Recovery of VA after treatment was correlated with disease duration.

CONCLUSION

Hyperintensity of the optic nerves ventral to the pituitary macroadenoma was associated with VA impairment. Recovery of VA after treatment was correlated with disease duration. MR imaging of the optic nerves can provide valuable information for management of pituitary macroadenoma.

Genetic variation and geographic distribution of porcine reproductive and respiratory syndrome virus in Japan

Porcine reproductive and respiratory syndrome virus (PRRSV) has two genotypes, the North American-type (NA-type) and the European-type (EU-type), and each genotype is also genetically diverged. We sequenced the ORF5 gene of 30 PRRSVs isolated from 23 prefectures of Japan during 1992 and 1993 and during 2000 and 2001. All of the isolates were of the NA-type. Phylogenetic analysis of the overall NA-type viruses isolated from around the world identified five major genetic clusters. The 1992-1993 Japanese samples belonged to only two genetic clusters, while the 2000-2001 samples included more diverged ORF5 genomes. One genetic cluster, which included 63% (20/32) of Japanese isolates, one Taiwanese isolate and one Chinese isolate, was mainly found in the eastern part of Japan. Another genetic cluster, which was found in various areas around the world, was distributed in the western part of Japan.

Nonsuppurative encephalitis in piglets after experimental inoculation of Japanese encephalitis flavivirus isolated from pigs

Nonsuppurative encephalitis was experimentally induced in 3-week-old piglets by a single intravenous inoculation of either of two strains (IB 2001 or AS-6) of Japanese encephalitis flavivirus (JEV) isolated from field pigs. The lesions, which consisted of neuronal necrosis, neuronophagia, glial nodules, and perivas-cular cuffing, were distributed in the cerebrum, midbrain, pons, medulla oblongata, and cerebellum, particularly in the gray matter of the frontal and temporal lobes and thalamus. The gray matter of the spinal cord of piglets that were given the AS-6 strain also was affected. JEV antigen was immunohistochemically detected in the cytoplasm of the nerve cells in the cortex of the frontal and temporal lobes and in the gray matter of the thalamus and midbrain. Two JEV strains isolated from field pigs exhibited neurovirulence, inducing nonsup-purative encephalitis in piglets.

Diagnostic value of carotid intima–media thickness and plaque score for predicting target organ damage in patients with essential hypertension

Carotid intima-media thickness (IMT) assessed by ultrasonography is regarded as an early predictor of general arteriosclerosis in patients with essential hypertension. However, the methods of measuring IMT have not been globally standardized, and it remains unclear whether conventional measurement of IMT represents the prevalence of hypertensive target organ damage. In this study, we verified the association between several commonly used carotid ultrasonographical parameters and the severity of hypertensive target organ damage (retinal arteriosclerosis, microalbuminuria, left ventricular hypertrophy (LVH)). Carotid ultrasonography, echocardiography, urinalysis, and funduscopy were performed in 184 patients (64 +/- 12 years, 96 males and 88 females) with various stages of essential hypertension. Carotid arteriosclerosis was assessed using four methodologically different methods: conventional-IMT, maximum-IMT (Max-IMT), Mean-IMT, and Plaque Score (the sum of all plaque thicknesses). Age and all carotid ultrasonographical parameters were significantly associated with albuminuria, retinal arteriosclerosis, and left ventricular mass index. High-sensitivity CRP was significantly correlated with retinopathy and LVH. Carotid parameters in patients with histories of cardiovascular events were significantly greater in those without events. Among all carotid parameters, Max-IMT showed the highest correlation coefficient of the severity of target organ damage, and showed significant association with CRP. Stepwise regression analysis revealed that Max-IMT was the independent factor for predicting target organ damage. Max-IMT is suggested to be the most reliable and simplest parameter for predicting hypertensive target organ damage including microangiopathy in patients with essential hypertension.

Disuse atrophy alterations in normal and low temperature environments during hindlimb unloading in Syrian hamsters

This study examined whether a hypothermic environment reduces experimentally-induced atrophy of skeletal muscle, as judged by histochemical findings. The hind limbs of hamsters in a hypothermic group were suspended and flexed into plantar positions at the ankle joint, and housed for one week at 8 to 12 degree celsius in a temperature-controlled room, while the normothermic group was housed at 23 to 25 degree celsius. Hypothermia did not significantly alter the average caloric intake, and the animals from the hypothermic group lost a significant amount of body weight when compared with the normothermic group. The hypothermic group retained more muscle wet-weight and myofibers cross-sectional area in the soleus and gastrocnemius muscles compared with the normothermic group. Our results indicate that a hypothermic environment inhibits short-term muscle atrophy. This inhibition may be caused by the increased caloric intake combined with a state similar to hibernation in low-temperature environments.

Positive association of CYP11B2 gene polymorphism with genetic predisposition to essential hypertension

Predispositions to essential hypertension and cardiovascular diseases are possibly associated with gene polymorphisms of the renin-angiotensin system. Gene polymorphisms of angiotensinogen and angiotensin-converting enzyme genes have been suggested to be risk factors for hypertension and myocardial infarction. Concerning the polymorphism of aldosterone synthase (CYP11B2) gene, earlier studies have shown inconsistent results in terms of its relation to hypertension. In the present case-control study, we investigated the association of -344T/C polymorphism in the promoter region of human CYP11B2 gene with genetic predisposition to hypertension. The genotype of -344T/C polymorphism was determined in essential hypertension subjects (n=250) and normotensive subjects (n=221). The distributions of three genotypes (TT, TC, and CC) were significantly different between the hypertensive and the normotensive groups (chi(2)=9.61, P=0.008). Namely, the frequency of C allele was higher in the hypertensive patients than in the normotensive subjects (34.2 vs 26.5%, P=0.010). Our data suggest that the -344C allele of CYP11B2 gene polymorphism is associated with the genetic predisposition to develop essential hypertension.

Comparison of the effects of amlodipine and losartan on 24-hour ambulatory blood pressure in hypertensive patients

Effects of amlodipine (AML), a long-acting calcium antagonist, and losartan (LOS), an angiotensin II receptor antagonist, on 24-hr blood pressure profile were compared in 15 patients with essential hypertension. After 4 weeks of placebo period, the patients were treated with AML or LOS in a random crossover design for 12-16 weeks each. Either drug was given once daily at 0800 and the doses were titrated so that the office blood pressure was reduced lower than 140/90mmHg. At the end of each period, 24-hr blood pressure was monitored. Average office blood pressure was lowered from 158 +/- 2/ 98 +/- 2 mmHg to 134 +/- 1/87 +/- 1 mmHg by AML and 134 +/- 2/88 +/- 1 mmHg by LOS. Average 24-hr blood pressure was also reduced from 144 +/- 3/ 92 +/- 2 mmHg to 131 +/- 2/84 +/- 2 mmHg by AML and 135 +/- 3/85 +/- 2 mmHg by LOS. The averaged 24-hr systolic blood pressure was significantly lower in AML than in LOS (p < 0.05). Then, the 24-hr blood pressure was analyzed for four segments; morning (0530-0900 h), daytime (0930-1800 h), evening (1830-2300 h) and night (2330-0500 h). Although the daytime blood pressure was comparable between AML and LOS, systolic blood pressure in the evening and morning hours were lower in AML than in LOS (133 +/- 2 vs. 138 +/- 3mmHg,p<0.01; 129 +/- 3 vs. 134 +/- 4,p<0.05). Troughtopeakratio of antihypertensive effect on systolic blood pressure was significantly greater in AML than in LOS (62 +/- 5% vs. 55 +/- 4%, p < 0.05). Either drug did not cause reflective increase in pulse rate over 24 hours. These results suggest that both AML and LOS are equally effective in lowering daytime blood pressure without eliciting reflex tachycardia, however, the antihypertensive effect of AML lasts longer than that of LOS. Such information seems important to achieve 24-hr blood pressure control using these drugs.

[A case of fundus albipunctatus with a retinol dehydrogenase 5 gene mutation in a child]

BACKGROUND

We examined a family with fundus albipunctatus in which mutation of the retinol dehydrogenase 5(RDH 5) gene was suspected to be the cause of this disease.

CASE

An 8-year-old girl had diffuse multiple white dots in her fundus except for the macula. She had good central vision. The amplitude of her electroretinogram wave was low, but it recovered after three hours of dark adaptation. Dark adaptometry showed an elevated threshold for rod adaptation. No visual field loss was observed. A homozygous missense mutation was found in exon 5 of the RDH 5 gene that substituted histidine for arginine at codon 280(Arg 280 His). Her mother had a normal fundus but was heterozygous for the same mutation.

CONCLUSION

A missense mutation of RDH 5(Arg 280 His) was found in a Japanese family with fundus albipunctatus.

Analysis of Second-order Kernel Response Components of Multifocal Electroretinograms Elicited from Normal Subjects

PURPOSE

It has been reported that the second-order kernel response components of multifocal electroretinograms (mERGs) reflect the electrical activity of the inner retinal layers. In this study, we have investigated whether the amplitudes of the second-order kernel response components correlate with the spatial distribution of human retinal ganglion cells.

METHODS

Multifocal electroretinograms were recorded using the Veris III system from 5 healthy subjects with different stimulus and recording parameters. The mERGs were analyzed using the Veris Science software programs. The stimuli consisted of densely arranged arrays of 103, 61, 37 or 19 hexagonal elements. Four minutes were required to record one set of mERG responses using 8 sessions, and 8 minutes using 16 sessions. The second-order kernel response components were extracted and analyzed using the Veris Science program.

RESULTS

The signal-to-noise ratio of the first-order kernel response components was improved considerably by the summation of the nine reproducible responses from the same subject but the second-order kernel response components were not. The summation of the nine reproducible responses was insufficient to identify an array of the second-order kernel response components. Both the first- and second-order kernel response components were larger when fewer hexagonal elements were used. There was no significant difference in the individual responses between the 4-minute and the 8-minute recordings. A response density analysis revealed a weak correlation between the amplitude distribution of the second-order kernel response components and the spatial distribution of human retinal ganglion cells.

CONCLUSIONS

The distribution of the amplitudes of the second-order kernel response components of the mERGs elicited from normal subjects did not correlate with the distribution of human ganglion cells. This suggests that the theory that second-order kernel response components arise from the activity of retinal ganglion cells should be reconsidered.

[Comparisons of factors affecting voiding disorders between patients with benign prostate hyperplasia and volunteers]

PURPOSE

The prostate size and motivation to visit clinics were investigated in patients with prostate hyperplasia.

OBJECTS AND METHODS

One hundred ninety-five patients who had urinary symptoms and visited our outpatient clinic between September 1994 and October 1999 and 268 age-matched volunteers in Mitaka City who underwent a medical examination of the prostate in June 1997 were compared. International Prostate Symptom Score (IPSS), Quality Of Life Score (QOL score), residual urine volume, prostate volume and urinary flow rate were measured.

RESULTS

The prostate volume of the volunteers was 20-25 cm3 irrespective of the age. The prostate size of the outpatients was larger than that of the volunteers for every age group. IPSS and QOL score were significantly higher in the outpatients than in the volunteers. Diurnal urinary frequency and sense of residual urine contributed to the discrimination index of the two groups more significantly than the other scores. There was a significant correlation between prostate volume and residual urine volume. The score of weak urinary steam was inversely and significantly correlated with peak urinary flow rate.

CONCLUSIONS

There was no age-related enlargement of the prostate gland. The prostate gland was significantly larger in the patients than in the volunteers even in those in their fifties. Urinary frequency and sense of residual urine are important factors for men to seek and receive medical care.

[The significance of early detection for prostate cancer in mass screening]

PURPOSE

In Mitaka city, mass screening for prostate cancer was conducted for 3 years from 1995 to 1997. Clinical stages were compared between patients found by screening and those diagnosed at our clinic during the same time. The significance of serum-free prostate specific antigen (PSA) in mass screening for prostate cancer was examined.

MATERIAL AND METHODS

A prospective clinical trial was conducted on men aged 50 years or older. The primary examination consisted of taking the international prostate symptom score, quality of life score, PSA (Tandem-R) and digital rectal examination (DRE). If PSA was greater than 4.0 ng./ml and/or if DRE suggested cancer, transrectal ultrasound-guided sextant prostate biopsies were indicated.

RESULTS

Of the men screened, 23.2% (320/1375) had serum PSA greater than 4.0 ng./ml. and/or suspicious findings on DRE. Biopsy was performed in 199 of 320 (62.1%). Cancer was detected in 21 (1.5%, 21/1375). Prostate cancer was found in one case among 154 males (0.65%, 1/154) who were screened twice or more. The cancer stage found by screening was significantly earlier than that diagnosed at the outpatient clinic (Wilcoxon's rank-sum test: p = 0.0047). Receiver operating characteristics analysis showed that the optimal free PSA-to-PSA ratio was 12%. Positive predictive value increased from 18% to 50% when free PSA-to-PSA ratio was combined with PSA.

CONCLUSION

1. Cancer detection rate was 1.5% in the mass screening in Mitaka City. 2. Cancer stage found by screening was significantly earlier than that diagnosed at the outpatient clinic. 3. Free PSA determination might eliminate unnecessary biopsies in men with PSA above 4.0 ng./ml with minimal loss of cancer detection.

Cellular mechanism of action of cognitive enhancers: effects of nefiracetam on neuronal Ca2+ channels

Cellular mechanisms underlying the cognition-enhancing actions of piracetam-like nootropics were studied by recording Ca2+ channel currents from neuroblastoma x glioma hybrid (NG108-15) cells and Xenopus oocytes expressing Ca2+ channels. In NG108-15 cells, nefiracetam (1 microM) produced a twofold increase in L-type Ca2+ channel currents. A similar, but slightly less potent effect was observed with aniracetam, whereas piracetam and oxiracetam exerted no such effects. Cyclic AMP analogs mimicked the nefiracetam action. N-type Ca2+ channel currents inhibited by leucine (Leu)-enkephalin by means of inhibitory G proteins (Go/Gi) were recovered promptly by nefiracetam, whereas those inhibited by prostaglandin E1 via stimulatory G proteins were not affected by nefiracetam. Cells treated with pertussis toxin (500 ng/mL, > 20 hours) were insensitive to nefiracetam. In Xenopus oocytes functionally expressing N-type (alpha1B) Ca2+ channels and delta-opioid receptors, nefiracetam was also effective in facilitating the recovery from Leu-enkephalin-induced inhibition. These results suggest that nefiracetam, and possibly aniracetam, may activate N- and L-type Ca2+ channels in a differential way depending on how they recover from Go/Gi-mediated inhibition.

Role of nitric oxide in the epileptogenesis of EL mice

PURPOSE

To understand the role of nitric oxide (NO) in the regulation of seizures, we measured the extracellular levels of the NO metabolites nitrite and nitrate as indices of NO generation in the parietal cortex, hippocampus, and temporal cortex of EL mice. Furthermore, alterations of neuronal, endothelial, and inducible nitric oxide synthetase (nNOS, eNOS, and iNOS, respectively) were observed to correlate them with epileptogenesis.

METHODS

EL mice of 20 weeks and 30 weeks of age (before and after the establishment of epileptogenesis, respectively) were used. Nitrite was quantified using the specific absorbancy of diazo dye. NOS isoenzymes (nNOS, iNOS, and eNOS) were also investigated in the hippocampus during development until mice were 30 weeks old. Samples (total protein, 8.33 to 8.43 microg) were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by immunoblotting.

RESULTS

EL mice that experienced repetitive seizures showed a remarkable increase in nitrite in the hippocampus at 30 weeks of age compared with EL mice that had no experience of seizures. nNOS and iNOS were major and minor components, respectively, and both increased in parallel with the development of epileptogenesis. eNOS was not detectable.

CONCLUSIONS

Excess iNOS (and subsequent increase in harmful NO) and deficient eNOS (and subsequent decrease in NO identified as an endothelium-derived relaxing factor) may work together to form a focus complex.

Presynaptic nicotinic acetylcholine receptors as a functional target of nefiracetam in inducing a long-lasting facilitation of hippocampal neurotransmission

Nefiracetam (1-10 microM), a nootropic (or cognition-enhancing) agent, persistently potentiated currents through Torpedo acetylcholine (ACh) receptors expressed in Xenopus oocytes as a result of interacting with a protein kinase C pathway and the ensuing protein kinase C phosphorylation of the receptors. A similar effect was found in neuronal nicotinic ACh receptors (alpha4beta2 and alpha7). In contrast, the other nootropic agents such as piracetam and aniracetam had no potentiating action on the receptors. A sustained enhancement in the activity of nicotinic ACh receptors induced by nefiracetam caused a marked increase in the glutamate release, leading to a long-term potentiation-like facilitation of hippocampal synaptic transmissions. One of the consistent neuropathologic features of the Alzheimer brain is a loss of nicotinic ACh receptors. This fact, together with the results of our study, raises the possibility that the loss of nicotinic ACh receptors may be a key factor in the decline of cognitive function observed in Alzheimer disease and that agents targeting neuronal nicotinic ACh receptors like nefiracetam could, therefore, be of great therapeutic importance.

Pattern electroretinogram elicited by a dartboard pattern

The receptive field size of retinal ganglion cells is closely related to their eccentricity from the fovea. To elicit larger pattern-reversal electroretinograms (P-ERGs), it may be useful to stimulate the retina with patterns having elements that parallel this change in receptive field size. We describe a dartboard pattern consisting of reversal elements that enlarge gradually from the central to the peripheral stimulus field. The utility of the dartboard pattern for eliciting P-ERG was investigated by comparing it with the conventional uniform checkerboard pattern, but with the other stimulus parameters remaining unchanged (96% contrast, 35.9 cd/m2 mean luminance, 3.3 rev/s temporal frequency, 15 degrees circular field). The dartboard pattern produced a significantly larger P50 amplitude than did the checkerboard pattern, while no difference in peak latency was found when 54 min of arc was used as a standard check size for the checkerboard pattern. The dartboard pattern for eliciting P-ERG should prove clinically useful.

Visual function in retinitis pigmentosa related to a codon 15 rhodopsin gene mutation

To determine the phenotype of a Japanese family in which retinitis pigmentosa cosegregates with a rhodopsin gene mutation, i.e. an asparagine-to-serine change at codon 15 (Asn-15-Ser), 5 affected and 5 unaffected members of one pedigree underwent several ophthalmic examinations as well as Ganzfeld electroretinography (ERG) and multifocal ERG. Genomic DNA samples were analyzed by PCR amplification, sequencing and restriction enzyme digestion. A codon 15 rhodopsin gene mutation (Asn-15-Ser) was found in all affected members. The region of pigmentary degeneration was localized in the lower hemiretina, and visual field defects corresponded to the retinal pigmentary changes. Scotopic ERG amplitudes, rather than photopic ERG amplitudes, were reduced. Multifocal ERG revealed a low magnitude of response density, even for the upper hemiretina, which showed no bony corpuscle pigmentation. Visual function in sectorial retinitis pigmentosa associated with rhodopsin gene codon 15 mutation is on the basis of the rod-cone dystrophy, regardless of differences in phenotypic expression.

[A case of familial juvenile gouty nephropathy associated with a right renal tumor]

We present a case of familial juvenile gouty nephropathy which was associated with a right renal tumor that was found incidentally. The patient was a 27-year-old woman who initially presented with acute gouty arthritis at the age of twenty years. Her mother and her sister had been attacked with acute gouty arthritis in their early twenties. Progressive deterioration in the renal function was noted in the three family members who had experienced gouty attack. Her mother was maintained on hemodialysis. As image diagnoses could not rule out malignancy in her right renal tumor, in situ non-ischemic enucleation of the right renal tumor using a microwave tissue coagulator(Microtaze) and a renal biopsy were performed. The pathological diagnosis of the renal tumor was tubulopapillary adenoma, and the renal biopsy showed minimal change in the glomeruli and tubules. The post-operative course was uneventful. The serum creatinine and creatinine clearance before and three months after the operation were 2.4 mg/dl and 2.6 mg/dl, 36.7 ml/min and 32.5 ml/min, respectively. The renal biopsy findings that glomerular and tubular changes were minimal and there was no tissue precipitation of uric acid or sodium urate, and the fact that her renal function decreased progressively despite the treatment of hyperuricemia suggested strongly that renal function might have deteriorated due to unknown factors other than hyperuricemia.

Visual function and gene analysis in a family with Oguchi's disease

A family with 1 case of retinitis pigmentosa (III-1) and 2 cases of Oguchi's disease (III-2, 3) was examined in terms of electrophysiology as well as molecular biology. The proband (III-3), a 42-year-old female, and 2 older brothers (III-1, 2, aged 52 and 45 years) and 2 unaffected members in the same family participated in this study. Corrected visual acuities of the individuals with Oguchi's disease (III-2, 3) were 1.2. On funduscopy, blood vessels stood out in relief against a metallic-appearing background and a Mizuo-Nakamura phenomenon was evident. Full-field electroretinograms (ERGs) recorded from the proband were indicative of rod dystrophy, but results of other electrophysiological examinations (multifocal ERG, pattern ERG and visual-evoked cortical potential recordings) were within normal limits. Patient III-1 had corrected visual acuities of RE 20 cm/m.m. and LE 30 cm/n.d., severe chorioretinal atrophy in both fundi, and full-field ERG revealed rod-cone dystrophy. Mutation of the arrestin gene (1147de1A) was detected in all 3 patients. Visual function in each patient coincides with that of retinitis pigmentosa or Oguchi's disease, respectively.

The anti-dementia drug nefiracetam facilitates hippocampal synaptic transmission by functionally targeting presynaptic nicotinic ACh receptors

Nefiracetam, a pyrrolidone derivative developed as an anti-dementia drug, persistently potentiated currents through neuronal nicotinic acetylcholine (ACh) receptors (alpha7, alpha4beta2) expressed in Xenopus oocytes, and the potentiation was blocked by either the selective protein kinase C (PKC) inhibitors, GF109203X and staurosporine, or co-expressed active PKC inhibitor peptide. In primary cultures of rat hippocampal neurons, nefiracetam increased the rate of nicotine-sensitive miniature excitatory postsynaptic currents, without affecting the amplitude, and the increase was inhibited by GF109203X. In addition, the drug caused a marked increase in the glutamate release from electrically stimulated guinea pig hippocampal slices, and the effect was abolished by the nicotinic ACh receptor antagonists, alpha-bungarotoxin and mecamylamine. Nefiracetam induced a long-lasting facilitation of synaptic transmission in both the CA1 area and the dentate gyrus of rat hippocampal slices, and the facilitation was inhibited by alpha-bungarotoxin and mecamylamine. Such facilitatory action was still found in the hippocampus with selective cholinergic denervation. The results of the present study, thus, suggest that nefiracetam enhances activity of nicotinic ACh receptors by interacting with a PKC pathway, thereby increasing glutamate release from presynaptic terminals, and then leading to a sustained facilitation of hippocampal neurotransmission. This may represent a cellular mechanism underlying the cognition-enhancing action of nefiracetam. The results also provide the possibility that nefiracetam could be developed as a promising therapeutic drug for senile dementia or Alzheimer's disease.

Histological study of masseter muscle in a mouse muscular dystrophy model (mdx mouse)

Histological changes in the masseter muscle were observed over time in mdx mice, a muscular dystrophy model. It was found that marked necrosis occurs about the time of weaning at around 4 weeks of age; then the tissue actively regenerates at 8 weeks and stabilizes as regenerated muscle with centronuclei at 15 weeks old. This study examined the centronucleus in regenerated muscle. The process from necrosis to regeneration in muscle fibers occurs a little later in the masseter muscle than in other limbic muscles. Regenerated muscles observed around 15 weeks after birth showed a moth-eaten appearance. Transmission Electron Microscope (TEM) observation of transverse sections of muscle fibers revealed that myofibrils surrounded lost regions in the area showing a moth-eaten appearance. Thus, some defensive mechanism may affect the ability of muscle fibers to maintain a function close to normal in mdx mice even though the muscle fibers develop muscular dystrophy. The function of the masseter muscle drastically changes from sucking to mastication behavior at around 4 weeks, and this was considered to influence the morphological changes in the muscle tissue. The moth-eaten appearance seen at 15 weeks may represent an appropriate myofibril reconstruction preventing invasion of the lost regions.

Artifact removal procedure distorts multifocal electroretinogram

PURPOSE

To study whether the Artifact Removal procedure available for eliminating artifacts in multifocal electroretinograms (mERG) works correctly or not.

METHODS

A test response was made using a photo-diode circuit. mERGs were recorded from 3 well-trained normal subjects using the Veris III system, and were then analyzed by the procedure that is included in the Veris Science (Artifact Removal) software program. The stimuli consisted of densely arranged arrays of 103 or 37 hexagonal elements. It took a total of 8 minutes to obtain one mERG record, and 16 sessions were required to complete this record. The first-order as well as the second-order kernel response components were extracted by Veris Science software, and the Artifact Removal procedure was used for both components.

RESULTS

The Artifact Removal procedure influenced both the test response on the center element as well as the neighboring traces just around the test response. After the repetitions of the Artifact Removal procedure, the shape of the test response changed considerably. Some of the traces of the second-order kernel response components elicited from a normal subject changed irregularly when the Artifact Removal procedure was repeatedly used. The noise increased at the first iteration of the Artifact Removal procedure.

CONCLUSION

This procedure has been considered useful for eliminating artifact distortion in mERG, but should be carefully checked by well-established testing methods before clinical use.

Functional expression of Fas and Fas ligand on human colonic intraepithelial T lymphocytes

The expression of Fas, a cell surface receptor directly responsible for triggering cell death by apoptosis, and its ligand (FasL) was investigated on both human colonic intraepithelial T lymphocytes (IELs) and peripheral blood mononuclear lymphocytes (PBMLs). FACS analysis indicated that IELs have increased expression of Fas compared with PBMLs, together with the progress activation marker, CD45RO. A discrete fraction of freshly isolated IELs also constitutively expressed FasL, perhaps as a result of recent in vivo activation. Using monoclonal antibody APO2.7, which detects mitochondrial 7A6 antigen specifically expressed by cells undergoing apoptosis, we further investigated the apoptosis-inducing effect of anti-Fas monoclonal antibody (CH11) on both IELs and PBMLs. FACS analysis revealed that CH11 increased the percentage of apoptotic cells, in IELs but not in PBMLs. Culture with anti-FasL monoclonal antibody (4H9) significantly recovered cell viability in IELs, but not in PBMLs. These results indicate that IELs constitutively express both Fas and FasL and that Fas crosslinking generates signals resulting in apoptosis, outlining a potential mechanism involved in intestinal tolerance.

The significance of the free-to-complexed prostate-specific antigen (PSA) ratio in prostate cancer detection in patients with a PSA level of 4.1-10.0 ng/mL

OBJECTIVE

To compare the ratio of free prostate specific antigen (fPSA), total PSA (tPSA) and complexed PSA (cPSA, measured using a novel immunoassay) with other variables used to detect prostate cancer in patients with intermediate serum PSA levels of 4.1-10.0 ng/mL.

PATIENTS AND METHODS

From July 1997 to August 1998, 140 consecutive patients were assessed; all had intermediate serum PSA levels and/or abnormal findings on a digital rectal examination. All patients underwent transrectal ultrasonography (TRUS)-guided biopsy, and the prostate and transition zone volumes were determined by TRUS. Free and tPSA were measured using the Tandem-R assay (Hybritech Corp., San Diego, CA). PSA complexed with alpha1-antichymotrypsin (cPSA) was measured using an appropriate assay. The ability of cPSA, free-to-total PSA ratio (f/tPSA), free-to-complexed PSA ratio (f/cPSA), tPSA density of the whole prostate (PSAD), of the transition zone (tPSATZ), and cPSA density of the whole prostate (cPSAD) and of the transition zone (cPSATZ) to improve the power of PSA in detecting prostate cancer was evaluated using receiver operating characteristic (ROC) curves. Results Of the 140 patients, 126 had histologically confirmed benign disease and 14 had prostate cancer. The cPSA alone had better specificity for detecting prostate cancer than had tPSA alone but the difference was not significant. The area under the ROC curve for f/cPSA was larger than those for all other variables. With a 93% sensitivity for detecting prostate cancer, a f/cPSA threshold of 25% would result in fewer unnecessary biopsies (40% f/cPSA specificity) than with all other PSA variables. The difference in the resolution was significant between f/cPSA and tPSA, cPSA, tPSAD and tPSATZ, but not with f/tPSA, cPSAD or cPSATZ. In patients with a prostate volume of < 30 mL, the cPSATZ showed better specificity for prostate cancer than tPSA alone.

CONCLUSION

Measuring the level of cPSA and its derivatives may provide better differentiation of prostate cancer and benign disease than tPSA alone in patients with a tPSA level of 4.1-10.0 ng/mL.

Molecular characterization and physiological role of ascorbate peroxidase from halotolerant Chlamydomonas sp. W80 strain

A cDNA clone encoding an ascorbate peroxidase was isolated from the cDNA library from halotolerant Chlamydomonas W80 by a simple screening method based on the bacterial expression system. The cDNA clone contained an open reading frame encoding a mature protein of 282 amino acids with a calculated molecular mass of 30,031 Da, preceded by the chloroplast transit peptide consisting of 37 amino acids. In fact, ascorbate peroxidase was localized in the chloroplasts of Chlamydomonas W80 cells; the activity was detected in the stromal fraction but not in the thylakoid membrane. The deduced amino acid sequence of the cDNA showed 54 and 49% homology to chloroplastic and cytosolic ascorbate peroxidase isoenzymes of spinach leaves, respectively. The enzyme from Chlamydomonas W80 cells was purified to electrophoretic homogeneity. The molecular properties of the purified enzyme were similar to those of the other algal ascorbate peroxidases rather than those of ascorbate peroxidases from higher plants. The enzyme was relatively stable in ascorbate-depleted medium compared with the chloroplastic ascorbate peroxidase isoenzymes of higher plants. The presence of NaCl (3%) as well as of beta-d-thiogalactopyranoside was needed for the expression of Chlamydomonas W80 ascorbate peroxidase in Escherichia coli.

Anticonvulsant actions of nefiracetam on epileptic EL mice and their relation to peripheral-type benzodiazepine receptors

Anticonvulsant actions of the nootropic drug nefiracetam were studied using EL mice, an animal model of epilepsy, in which peripheral-type benzodiazepine receptors (PBRs) might be involved in their epileptogenesis. Nefiracetam, when administered orally t o EL mice, inhibited convulsions induced by the PBR agonist, Ro 5-4864, with an ED(50) of 17.2 mg/kg, whereas it did not inhibit the drug-induced convulsions in control DDY mice. When administered intravenously (i.v.) to DDY mice, nefiracetam and other piracetam-like nootropics inhibited the Ro 5-4864-induced convulsions in the sequence of nefiracetam>aniracetam>>oxiracetam, piracetam. Spontaneous EL mouse seizures were also inhibited by these nootropics with a similar rank order of potencies. Binding studies for PBRs, performed on crude membranes of brain tissues of these mice, revealed that [3H]Ro 5-4864 and [3H]PK 11195 bindings were both inhibited by micromolar concentrations of nootropic agents in the sequence of nefiracetam> aniracetam>>oxiracetam, piracetam. The results suggest that nefiracetam may exert an anticonvulsant action through interacting with a low-affinity type of PBR in the brain, and could be developed as a promising therapeutic drug for neurological disorders including epilepsies.

Enhancing effect of 5 alpha-cyprinol sulfate on mucosal membrane permeability to sodium ampicillin in rats

Effect of 5 alpha-cyprinol sulfate, a bile alcohol sulfate specific to carp bile, on rectal membrane permeability to sodium ampicillin (AMP Na) was examined in rats. AMP Na is not easily absorbed through rat rectal membrane without aid. 5 alpha-Cyprinol sulfate significantly enhanced the rectal membrane permeability to AMP Na even at a low concentration (6.25 mM), though sodium taurocholate needed a higher concentration (25 mM). Co-administration of phosphatidylcholine significantly suppressed the enhancing action of both sodium taurocholate and 5 alpha-cyprinol sulfate. On the other hand, calcium ion did not suppress the action of 5 alpha-cyprinol sulfate, although it did clearly suppress the action of sodium taurocholate. In conclusion, 5 alpha-cyprinol sulfate was found to have a potent enhancing effect on mucosal membrane permeability to water-soluble compounds. The enhancing mechanism of 5 alpha-cyprinol sulfate appeared to be different from that of sodium taurocholate.

A basic investigation of multifocal electroretinogram: reproducibility and effect of luminance

PURPOSE

To investigate the reproducibility as well as the effect of luminance in multifocal electroretinogram (mERG).

METHODS

Multifocal electroretinogram recordings were repeated on different days in 6 normal subjects using the Veris III system. The mean luminance of the monitor displaying the stimuli was randomly varied by five kinds of neutral density (ND) filters.

RESULTS

The standard deviation of mERG amplitude from the macular region was approximately 10% of the mean value for each normal subject. Reproducibility largely depended on the condition of the subject and placement of the contact lens electrode. With decreases in the mean luminance of the monitor, the amplitude of mERG decreased exponentially, whereas the peak latency increased linearly. mERGs elicited from a patient with mild cortical cataract resembled the mERGs obtained from the control group using an ND filter between -0.30 and -0.52 log, whereas two patients with typical retinitis pigmentosa showed much lower response densities in mERGs.

CONCLUSIONS

It is necessary to pay attention to the reproducibility and the luminance effect to obtain reliable mERGs.

A solid-state culture system using a cellulose carrier containing defined medium as a useful tool for investigating characteristics of koji culture

The purpose of this article is to establish a new solid-state culture system that uses a defined medium and allows control of the chemical factors in the medium in solid-state cultivation. To achieve this purpose, we produced a solid substrate, in which the defined medium was packed in a cellulose carrier with agar, and named it "cellulose agar cube (CA-cube)". In order to obtain growth conditions similar to koji culture, we then determined the moisture content of the CA-cube. Five runs of column reactor operations were carried out at various moisture contents of the CA-cube in the range of 50-90%. A very similar mycelial morphology to that of koji culture was observed on the surface of CA-cube with moisture content lower than 63%. The glucoamylase production and the production ratio of glucoamylase to alpha-amylase (G/A ratio) were both increased exponentially with decreasing moisture content and reached 237.5 units per g dry solid and 13.59, respectively, at the moisture content of 50%, which are almost comparable to those of koji culture. In addition, the glucoamylase "glaB", which is mainly produced in koji culture, was observed in the CA-cube culture with low moisture content. These results indicate that growth conditions similar to koji culture could be attained by the column reactor culture with the CA-cube.

Bile acid sulfonate and 7-alkylated bile acid analogs: effect on intestinal absorption of taurocholate and cholesterol 7alpha-hydroxylase activity in cultured rat hepatocytes

The effects of sulfonate analogs of cholic (C), chenodeoxycholic (CDC), and ursodeoxycholic acid (UDC) and three 7-alkylated CDCs--7-methyl-, 7-ethyl-, and 7-propyl-CDCs--on taurocholate absorption from rat terminal ileum in situ and on cholesterol 7alpha-hydroxylase activity in primary culture of the rat liver were investigated. The sulfonate analogs of two dihydroxy bile acids CDC and UDC, but not C, significantly decreased the absorption of taurocholate. Taurine conjugates of 7-alkylated CDC slightly decreased the taurocholate absorption, and tauro-7-propyl-CDC significantly suppressed the absorption. Although the sulfonate analogs of C and CDC reduced cholesterol 7alpha-hydroxylase activity by 40% and 60% compared to control, UDC-sulfonate analog did not affect enzymatic activity. These results were consistent with those of the lead compounds, C, CDC, and UDC. The introduction of methyl group at C-7 position of CDC attenuated the reduction in cholesterol 7alpha-hydroxylase activity by CDC. However, elongation of the alkyl group resulted in an inhibitory effect. The present study revealed the following: 1) bile acid sulfonates act on cholesterol and bile acid metabolism in a similar manner as taurine conjugated bile acids; and 2) the biologic properties of CDC could be altered by the introduction of alkyl group at C-7 position.

REP-1 gene mutations in Japanese patients with choroideremia

BACKGROUND

Choroideremia (CHM) is an X-linked progressive dystrophy of the choroid, retinal pigment epithelium, and retina. Recently, the REP-1 gene was isolated and the causative mutations in the gene were detected in patients with CHM. In a previous study, we described a Japanese family with CHM who had a mutation in the REP-1 gene. In the present study, we performed extensive analysis of the REP-1 gene in patients with CHM from several institutions in Japan.

METHODS

Twenty-six patients with CHM and 5 unaffected females from 22 independently ascertained families were examined. Exons 1-15 of the REP-1 gene were screened by single-strand conformation polymorphism. The DNA fragments suspected of any variations were directly sequenced.

RESULTS

Fifteen different mutations, including one previously reported mutation, were detected in 18 families. In addition, carrier status was proven in four unaffected females found to be heterozygous for the mutant allele.

CONCLUSIONS

Fifteen different mutations of the REP-1 gene were detected in 18 Japanese families. There were no hot spots for the mutations and no missense mutations. The results show that REP-1 gene defects cause CHM in Japanese patients, and the mutations in these Japanese patients differed from the mutations reported for CHM patients in Europe, Canada, and America except for R267X and 1313delTC. These findings suggest that the mutations occurred independently in the Japanese patients.

Production of radioactive endovascular stents by implantation of 133Xe ions

A coronary stent was made radioactive by implantation of 133Xe ions for the purpose of suppressing the renarrowing of the part of blood vessel in which the stent is implanted. Electrons of relatively low energies emitted in the decay of 133Xe may give an antiproliferative effect of ionizing radiation to the intimal cells within a limited range of 1 mm. A 133Xe+ beam accelerated at 40 or 60 keV was directed to several stainless steel stents mounted on a target-holder table that could revolve and move up and down to distribute the 133Xe+ ions within a stent as well as among the stents. The radioactive stents produced contained up to 100 kBq of 133Xe and were implanted into the abdominal aortas of rabbits. Neointimal thickening was analyzed by histomorphometry for samples taken 4 weeks after stent implantation. The results indicate that the radioactive stents have a potential to suppress neointimal hyperplasia in rabbits.

A 'long-term-potentiation-like' facilitation of hippocampal synaptic transmission induced by the nootropic nefiracetam

Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam.

Isolation of an Arabidopsis thaliana mutant in which the multiplication of both cucumber mosaic virus and turnip crinkle virus is affected

During the systemic infection of plants by viruses, host factors play an important role in supporting virus multiplication. To identify and characterize the host factors involved in this process, we isolated an Arabidopsis thaliana mutant named RB663, in which accumulation of the coat protein (CP) of cucumber mosaic virus (CMV) in upper uninoculated leaves was delayed. Genetic analyses suggested that the phenotype of delayed accumulation of CMV CP in RB663 plants was controlled by a monogenic, recessive mutation designated cum2-1, which is located on chromosome III and is distinct from the previously characterized cum1 mutation. Multiplication of CMV was delayed in inoculated leaves of RB663 plants, whereas the multiplication in RB663 protoplasts was similar to that in wild-type protoplasts. This suggests that the cum2-1 mutation affects the cell-to-cell movement of CMV rather than CMV replication within a single cell. In RB663 plants, the multiplication of turnip crinkle virus (TCV) was also delayed but that of tobacco mosaic virus was not affected. As observed with CMV, the multiplication of TCV was normal in protoplasts and delayed in inoculated leaves of RB663 plants compared to that in wild-type plants. Furthermore, the phenotype of delayed TCV multiplication cosegregated with the cum2-1 mutation as far as we examined. Therefore, the cum2-1 mutation is likely to affect the cell-to-cell movement of both CMV and TCV, implying a common aspect to the mechanisms of cell-to-cell movement in these two distinct viruses.

[Facilitatory actions of the cognitive enhancer nefiracetam on neuronal Ca2+ channels and nicotinic ACh receptors: their intracellular signal transduction pathways]

Nootropics are proposed to serve as cognition enhancers. The underlying mechanism, however, is largely unknown. We have attempted to assess the intracellular signal transduction pathways mediating the action of nefiracetam, a nootropic agent, on neuronal Ca2+ channels and nicotinic ACh receptors. In NG108-15 cells, nefiracetam (1 microM) enhanced the activities of N/L-type Ca2+ channels without affecting T-type The nefiracetam action was mimicked by dibutyryl cAMP (1 mM), or blocked by pertussis toxin (PTX), indicating that PTX-sensitive inhibitory G-proteins and cAMP-dependent pathways mediate the drug action. Nefiracetam also exerted a dose-dependent biphasic effect on Torpedo nicotinic acetylcholine (nACh) receptors expressed in Xenopus oocytes, in which the drug induced a short-term depression of ACh-evoked currents at submicromolar concentrations (0.01-0.1 microM) and a long-term enhancement of the currents at micromolar concentrations (1-10 microM). The depression was caused by activation of PTX-sensitive G-protein-regulated cAMP-dependent protein kinase (PKA) with subsequent phosphorylation of the ACh receptors; in contrast, the enhancement was caused by activation of Ca(2+)-dependent protein kinase C (PKC) and the ensuing PKC phosphorylation of the receptors. It is concluded that nefiracetam interacts with PKA and PKC pathways, which may explain a cellular mechanism for the action of cognitive enhancers.