Identification of human cytochrome P450 enzymes involved in the formation of 4-hydroxyestazolam from estazolam

To predict drug interactions with estazolam, the biotransformation of estazolam to its major hydoxylated metabolite, 4-hydroxyestazolam was studied in vitro using pooled human liver microsomes and individual expressed human cytochrome P450 (CYP) enzymes. Estazolam was metabolized to 4-hydroxyestazolam according to the Hill kinetic model in pooled human liver microsomes. The Km value for the 4-hydroxylation of estazolam was 24.1 microM, and the Vmax value was 52.6 pmol min(-1)mg(-1) protein. The formation of 4-hydroxyestazolam from estazolam in pooled human liver microsomes was significantly inhibited by itraconazole and erythromycin, specific CYP3A4 inhibitors, in a dose-dependent manner, with IC50 values of 1.1 and 12.8 microM, respectively. When estazolam was incubated with expressed human CYP enzymes (CYP1A2, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4), it was metabolized only by CYP3A4. In conclusion, the biotransformation of estazolam to 4-hydroxyestazolam was catalyzed by CYP3A4.

Effects of genetic polymorphism of cytochrome P450 enzymes on the pharmacokinetics of benzodiazepines

Pharmacogenetic studies have shown that several cytochrome P450 (CYP) enzymes exhibit genetic polymorphisms. Several benzodiazepines (BZPs) are metabolized predominantly or partly by polymorphic CYP2C19 and CYP3A4/5. The pharmacokinetics of diazepam, etizolam, quazepam and desmethylclobazam have been shown to be affected by CYP2C19 polymorphism. The CYP3A5 polymorphism has been reported to affect the pharmacokinetics of alprazolam, but its effect on midazolam kinetics has been inconclusive. For etizolam and desmethylclobazam, some data suggest that CYP2C19 deficiency leads to side-effects or toxicity. For the remaining BZPs the clinical significance of the observed pharmacokinetic changes remains unclear. Further studies on the effects of genetic polymorphisms of CYP enzymes on the pharmacokinetics and pharmacodynamics of BZPs are necessary to guide treatment individualization and optimization.

Brief communications: visualization of coronary arteries in rats by 3-dimensional real-time contrast echocardiography

Angiogenesis is under intense investigation to advance the treatment of various ischemic diseases. Small animals, such as mice and rats, are often used for this purpose. However, evaluating the structure of coronary arteries in small animals in situ is not easy. We succeeded in visualizing the coronary artery in rats on 3-dimensional real-time contrast echocardiography using a high-frequency transducer. These methods will be applied for more convenient assessment in a new study, examining issues such as angiogenesis using rats in situ.

Three-dimensional reconstruction of coronary arteriole plexus image by contrast echocardiography using a high-frequency transducer

OBJECTIVE

This study was established to examine the efficacy of a high-frequency liner probe for visualizing fine anatomy of coronary microcirculation.

METHODS

The vessel size and its velocity-time integral at the anterior wall in dogs by real-time contrast echocardiography with high-frequency liner probe and pulse Doppler methods, and the coronary flow volume, were measured before and after adenosine triphosphate injection. A 3-dimensional (3D) image was reconstructed by the built-in 3D system using intermittent flash echocardiographic images.

RESULTS

The increments of flow volume calculated from vessel sizes and velocity-time integral were well correlated with those of coronary flow volume. Using intermittent flash echocardiographic images, fine dots and lines of contrast echocardiographic-expected arterioles were evident, and easily and quickly reconstructed as coronary plexus by 3D system.

CONCLUSION

A high-frequency liner probe provides the fine-vessel images to evaluate those morphologic changes; a 3D reconstruction image could provide new information about coronary arterioles.

Quantitative assessment of microcollateral recruitment during coronary occlusion using real-time intravenous myocardial contrast echocardiography

BACKGROUND

Residual collateral-derived myocardial blood flow (MBF) (A x beta) is important to protect against myocardial ischemia after acute coronary occlusion.

METHODS

Recruitment of microcollateral was assessed in 22 dogs with left circumflex coronary artery occlusion by analysis of MBF and regional wall thickening (WT) using real-time myocardial contrast echocardiography.

RESULTS

Video intensity and WT at the center of risk area were significantly lower than those at the border of risk area. The video intensity, A value, beta value, and MBF correlated well with WT after left circumflex coronary artery occlusion. The WT of the area with above 25% of normal MBF was preserved and was higher than that at below 25%. However, the deterioration of WT was not distinguished according to A value.

CONCLUSION

Real-time myocardial contrast echocardiography is a useful noninvasive method to evaluate collateral-derived MBF, which can be a reliable index of protection against myocardial ischemia.

Unusual fracture of the humerus in a volleyball player: a case report

We describe a case of a female high school volleyball player who suffered a humeral shaft fracture while executing a floater serve. Based on the patient's history, a stress fracture was initially suspected. However, plain radiographs showed no periosteal reactions, callus formation or osteosclerosis, and thus we could not make a definite diagnosis of "stress fracture". It is suggested that an instantaneous muscle force in addition to rotational forces applied by impact with the ball caused the fracture. Her fracture healed without any subsequent disabilities based on a conservative medical management with a plaster splint, and she returned to the volleyball team. The inaccuracy of her serve form in addition to her own muscular force might be involved in the mechanism of injury. Instruction on achieving appropriate serve form might help prevent such fractures.

An unusual dorsal fracture-dislocation of the proximal interphalangeal joint

A case of dorsal fracture-dislocation of the proximal interphalangeal joint in which the volar plate had been pulled from its distal attachment without bony or cartilaginous attachments and the lip of the volar plate had also been detached separately and was obstructing full flexion of the joint is presented. A tentative mechanism of causation of this unusual variant of a common injury is suggested.

Comprehensive diagnosis of growth rates of the ablative Rayleigh-Taylor instability

The growth rate of the ablative Rayleigh-Taylor instability is approximated by gamma = square root[kg/(1 + kL)] - beta km/rho(a), where k is the perturbation wave number, g the gravity, L the density scale length, m the mass ablation rate, and rho(a) the peak target density. The coefficient beta was evaluated for the first time by measuring all quantities of this formula except for L, which was taken from the simulation. Although the experimental value of beta = 1.2+/-0.7 at short perturbation wavelengths is in reasonably good agreement with the theoretical prediction of beta = 1.7, it is found to be larger than the prediction at long wavelengths.

No association between CART (cocaine- and amphetamine-regulated transcript) gene and methamphetamine dependence

Cocaine- and amphetamine-regulated transcript (CART) was originally discovered as a peptide that increased in the rat striatum after injection of a psychostimulant drug, such as cocaine or amphetamine, and is suggested to play potential roles in drug dependence. We tested the genetic association between the CART gene and methamphetamine (METH) dependence and/or psychosis. The subjects were 203 patients with METH dependence and 239 age- and gender-matched healthy controls. Two single nucleotide polymorphisms (SNPs) of the CART gene, -156A>G and IVS1 + 224G>A, were examined . There were no significant differences in genotype and allele distributions of the polymorphisms between patients with METH dependence and/or psychosis and controls. Neither were significant differences in subgroups of clinical phenotypes, for example, age at first consumption of METH, latency to onset of psychotic symptoms after the first consumption of METH, prognosis of psychosis after therapy, complication of spontaneous relapse to a psychotic state, or multisubstance abuse status, observed. The present findings suggest that the CART gene may not play a pivotal role in the development of METH dependence and psychosis, at least in a Japanese population.

Association study of the tumor necrosis factor-alpha gene and its 1A receptor gene with methamphetamine dependence

Recent preclinical findings that repeated treatment with methamphetamine (METH) induced an increase in tumor necrosis factor-alpha (TNF-alpha) mRNA in some brain regions and that TNF-alpha blocked METH neurotoxicity and rewarding effects suggest TNF-alpha, a multifunctional pro-inflammatory cytokine, may be involved in METH dependence. We hypothesized that genetic polymorphisms of the TNF-alpha gene and its receptor genes may be associated with vulnerability to METH dependence. Genetic association of -308G>A and -857C>T in the promotor region of the TNF-alpha gene, and 36A>G in exon 1 of the TNF receptor 1A gene (TNFR-SF1A), were analyzed in patients with METH dependence (n = 185) and healthy controls (n = 221) in a Japanese population. No significant association of alleles or haplotypes of the TNF-alpha or TNFR-SF1A genes with METH dependence was found. Neither was any significant association of clinical phenotype with METH dependence found. These results suggest that genetic variations in the TNF-alpha gene and its receptor genes may not be involved in individual vulnerability to METH dependence.

Corrected quantification method to determine myocardial blood flow using real-time myocardial contrast echocardiography

BACKGROUND

The quantitative assessment of myocardial blood flow using real-time myocardial contrast echocardiography is based on a replenishment of bubble density after bubble destruction by high-power ultrasound exposure (burst). However, all microbubbles in the myocardial vessels are not necessarily completely destroyed, which results in unreliable data of the replenishment curve analysis.

OBJECTIVE

The aim of this study was to propose a corrected equation for the replenishment curve analysis based on the hypothesis in which the initial intensity just after burst should be equivalent to the baseline intensity before contrast infusion, and to examine whether the regional difference of myocardial perfusion parameters could be minimized by the use of corrected equation of replenishment curve.

METHODS

Myocardial opacification of the left ventricular short-axis view was observed using low mechanical index during infusion of Definity in open-chest dogs. Bubble destruction was set in two ways, either high (0 dB) or low (-11 dB) power burst. The videointensity (VI) of baseline before contrast infusion (f-value) was assumed as an initial intensity after complete bubble destruction. Changes of the VI after burst were fitted to both exponential functions: y = a (1 - e(-beta t)) + c (conventional equation) and y = a (1 - e(-beta(t - d))) + f (corrected equation). The c-value was the measured VI just after burst. The d-value was the hypothetical time of onset of the replenishment curve if all bubbles were completely destroyed. The plateau VI was defined as the A-value, which was the sum of a- and c-values or a- and f-values, respectively. The maximal difference of beta-value among myocardial regions was calculated by either equation.

RESULTS

The A-value was almost identical in either equation regardless of the acoustic power of burst. The beta-value by the conventional equation was higher after the incomplete burst than that after complete burst (0.45 +/- 0.12 vs 0.54 +/- 0.16). By contrast, the beta-value calculated by the corrected equation was almost identical despite complete or incomplete bursts (0.46 +/- 0.13 vs 0.48 +/- 0.15). The maximal difference of beta-value was significantly reduced by the use of corrected equation (conventional 0.24 +/- 0.14 vs corrected 0.18 +/- 0.10).

CONCLUSIONS

Variation of beta-value because of the incomplete bubble destruction can be minimized by using the corrected equation: y = a (1 - e(-beta(t - d))) + f. Further, the corrected equation can improve the regional variation of beta-value.

Impact of the Coronary Flow Reduction at Rest on Myocardial Perfusion and Functional Indices Derived from Myocardial Contrast and Strain Echocardiography

BACKGROUND

The severity of the coronary flow reduction that corresponds to myocardial perfusion and functional abnormalities remains unclear. We estimated the impact of various severities of flow-limiting coronary stenosis at rest on myocardial perfusion and functional indices from myocardial contrast echocardiography and tissue strain imaging and characterized the relationship between both the indices.

METHODS

Four levels of flow-limiting stenoses (slight, mild, moderate, severe) of the left circumflex coronary artery were examined in 10 open-chest dogs. In the left circumflex coronary artery area, plateau videointensity and time to plateau (TP) of the replenishment curve from myocardial contrast echocardiography were calculated for perfusion analysis, and peak systolic strain and postsystolic strain index (PSI) from tissue strain imaging were measured for functional analysis.

RESULTS

Plateau videointensity and peak systolic strain tended to decrease with increased severity of stenosis, although these differences did not reach the level of statistical significance. TP and PSI were significantly increased in the context of moderate (>or=30-<50%) and severe (>or=50%) flow reduction when compared to baseline values (TP, moderate 1.69 +/- 0.20 and severe 1.77 +/- 0.25 vs baseline 0.93 +/- 0.17, P < .01, respectively; PSI, moderate 0.96 +/- 0.15 and severe 1.28 +/- 0.32 vs baseline 0.59 +/- 0.18, P < .05 and P < .01, respectively). Further, TP and PSI were positively correlated with flow reduction (r = 0.81 and r = 0.84, P < .0001, respectively), and PSI was positively correlated with TP (r = 0.72, P < .0001).

CONCLUSIONS

In contrast to conventional indices, such as plateau videointensity and peak systolic strain, novel indices, such as TP and PSI, were both able to detect 30% or greater coronary flow reduction at rest.

Pharmacokinetics and pharmacodynamics of etizolam are influenced by polymorphic CYP2C19 activity

OBJECTIVE

To examine the effect of cytochrome P450 (CYP) 2C19 activity on the single-dose pharmacokinetics and pharmacodynamics of etizolam.

METHODS

The subjects were 21 healthy Japanese volunteers. The two mutated alleles (CYP2C19*2 and CYP2C19*3) causing absent CYP2C19 activity were identified by a polymerase chain reaction method. Twelve subjects were extensive metabolizers (EMs) with no or one mutated allele, and nine subjects were poor metabolizers (PMs) with two mutated alleles. The subjects received a single oral 1-mg dose of etizolam, and blood samplings and evaluation of psychomotor function were conducted up to 24 h after dosing.

RESULTS

The PMs had significantly larger total area under the plasma concentration-time curve (287+/-74 vs 178+/-122 ng.h/ml, p<0.05) and longer elimination half-life (14.8+/-4.2 vs 10.5+/-3.9 h, p<0.05) of etizolam than the EMs. The area under the score-time curve from 0 to 8 h of the Stanford Sleepiness Scale was significantly larger in the PMs than in EMs (28.9+/-5.2 vs 22.9+/-6.9 score.h, p<0.05).

CONCLUSION

The present study suggests that the single-dose pharmacokinetics and pharmacodynamics of etizolam are influenced by polymorphic CYP2C19 activity.

Induction of the metabolism of etizolam by carbamazepine in humans

OBJECTIVE

To examine the effect of carbamazepine on the single oral dose pharmacokinetics of etizolam.

METHODS

Eleven healthy male volunteers received carbamazepine 200 mg/day or placebo for 6 days in a double-blind, randomized, crossover manner, and on the sixth day they received a single oral 1-mg dose of etizolam. Blood samplings and evaluation of psychomotor function by the Digit Symbol Substitution Test and Stanford Sleepiness Scale were conducted up to 24 h after etizolam dosing. Plasma concentration of etizolam was measured using high-performance liquid chromatography.

RESULTS

Carbamazepine treatment significantly decreased the peak plasma concentration (17.5+/-4.1 ng/ml versus 13.9+/-4.1 ng/ml; P<0.05), total area under the plasma concentration-time curve (194.8+/-88.9 ng h/ml versus 105.9+/-33.0 ng h/ml; P<0.001), and elimination half-life (11.1+/-4.6 h versus 6.8+/-2.8 h; P<0.01) of etizolam. No significant change was induced by carbamazepine in the two pharmacodynamic parameters.

CONCLUSIONS

The present study suggests that carbamazepine induces the metabolism of etizolam.

Adenosine triphosphate stress myocardial contrast echocardiography detects coronary artery stenosis with greater sensitivity than wall-motion abnormality measurements

BACKGROUND

Although stress myocardial contrast echocardiography (MCE) can be used to detect coronary stenosis, its efficacy relative to other methods, such as detection of wall-motion abnormalities, remains unknown. Thus, the goal of this study was to compare the sensitivity of MCE versus wall-motion abnormality detection in the assessment of coronary artery stenosis.

METHOD

Nine dogs with severe but nonflow limiting stenosis in the circumflex coronary artery underwent evaluation with real-time MCE along the short-axis view during infusion of Optison. The equation of y = a (1 - e -betat ) + c, which fits the replenishment curve of MCE, was calculated in the midseptum (normal region) and in the lateral wall (ischemic region) before and during adenosine triphosphate infusion. Wall-motion abnormalities were also evaluated by visual assessment and by measurement of wall thickening.

RESULTS

Area under the receiver operating characteristic curve in beta- and A x beta-value, and percent wall thickening, was 0.963, 0.963, and 0.889, respectively, indicating that the diagnostic accuracy for detecting the coronary artery stenosis by real-time MCE was higher than that by the wall-motion assessment.

CONCLUSION

Real-time MCE has higher sensitivity in detecting coronary stenosis during adenosine triphosphate stress test when compared with wall-motion assessment.

Noninvasive vessel-selective perfusion imaging with intravenous myocardial contrast echocardiography

BACKGROUND

Intravenous myocardial contrast echocardiography (MCE) cannot identify each perfusion area of coronary vessels separately. However, by destroying microbubbles passing through a specific vessel using high-power ultrasound during intravenous MCE, vessel-selective perfusion imaging (VSPI) may be feasible.

METHODS

In 10 open-chest dogs, intermittent short-axis images were obtained during contrast agent infusion using an ultrasound system. For VSPI, a probe coupled to another ultrasound machine was placed on the proximal left circumflex coronary artery (LCx). High-power ultrasound pulses were transmitted to destroy bubbles passing through the LCx. A negative contrast area on VSPI was considered to represent the perfusion area of the LCx (LCx-VSPI). A negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye were used as gold standards for defining the LCx perfusion area. LCx-VSPI was compared with a negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye.

RESULTS

Despite lack of LCx occlusion, high-power destructive pulses produced a definite area of negative contrast on the LCx region. Decreased power of ultrasound pulses resulted in disappearance of the negative contrast area. An excellent relationship was demonstrated between both LCx-VSPI and a negative contrast area on conventional MCE during LCx occlusion (r = 0.93, P <.0001), and LCx-VSPI and a region without staining by Evans blue dye (r = 0.92, P =.0002).

CONCLUSION

VSPI during intravenous MCE may be feasible for noninvasive assessment of perfusion areas associated with specific vessels.

Inhibition of the metabolism of etizolam by itraconazole in humans: evidence for the involvement of CYP3A4 in etizolam metabolism

OBJECTIVE

To clarify the involvement of cytochrome P450 (CYP) 3A4 in the metabolism of etizolam.

METHODS

The effects of itraconazole, a potent and specific inhibitor of CYP3A4, on the single oral dose pharmacokinetics and pharmacodynamics of etizolam were examined. Twelve healthy male volunteers received itraconazole (200 mg/day) or placebo for 7 days in a double-blind randomized crossover manner, and on the 6th day they received a single oral 1-mg dose of etizolam. Blood samplings and evaluation of psychomotor function using the Digit Symbol Substitution Test and Stanford Sleepiness Scale were conducted up to 24 h after etizolam dosing. Plasma concentration of etizolam was measured by means of high-performance liquid chromatography.

RESULTS

Itraconazole treatment significantly increased the total area under the plasma concentration-time curve (AUC; 213+/-106 ng rectangle h/ml versus 326+/-166 ng rectangle h/ml, P<0.001) and the elimination half-life (12.0+/-5.4 h versus 17.3+/-7.4 h, P<0.01) of etizolam. The 90% confidence interval of the itraconazole/placebo ratio of the total AUC was 1.38-1.68, indicating a significant effect of itraconazole. No significant change was induced by itraconazole in the two pharmacodynamic parameters.

CONCLUSION

The present study suggests that itraconazole inhibits the metabolism of etizolam, providing evidence that CYP3A4 is at least partly involved in etizolam metabolism.

[Premature ventricular contraction during myocardial contrast echocardiography: relationship with imaging method, acoustic power and dose of contrast agent]

OBJECTIVES

This study investigated the influence of imaging method, acoustic power, and dose of contrast agent on the occurrence of premature ventricular contraction during myocardial contrast echocardiography.

METHODS

Myocardial contrast echocardiography was performed with a Toshiba POWER VISION 6000 and YM454 (Definity in USA) contrast agent. Myocardial contrast echocardiography in the short-axis view at the mid-papillary muscle level and electrocardiography in lead II were recorded on videotape in nine awake beagles. The imaging method was continuous, using 1:1 and 1:4 intermittent end-systolic triggered mode. Acoustic power was low, middle and high (as mechanical index, 0.4, 0.8 and 1.0 at continuous mode and 0.6, 1.0 and 1.4 at intermittent mode). YM454 was given intravenously at doses of 1, 10, 30, 50 and 100 microliters/kg/min. Premature ventricular contractions were counted on the videotape for each experimental condition. The examination was repeated on a separate day to ascertain the reproducibility.

RESULTS

At low and middle acoustic power, no premature ventricular contraction was induced with any combinations of YM454 doses and trigger intervals. The highest incidence of premature ventricular contraction was 5.1% of all ultrasound pulses at the combination of high acoustic power, 1:4 intermittent and 30 microliters/kg/min of YM454. All premature ventricular contractions induced by trigger mode were observed concomitantly to the end-systolic phase. Reproducibility was low at 0.9%.

CONCLUSIONS

Although high acoustic power, intermittent myocardial contrast echocardiography with high dose of contrast agent induced premature ventricular contractions, the incidence of premature ventricular contractions was low. Low acoustic power or low dose of contrast agent induced no premature ventricular contractions.

Myocardial blood flow parameters derived from contrast replenishment using harmonic power Doppler imaging are underestimated by ultrasound signal attenuation

The effect of ultrasound signal attenuation on myocardial blood flow parameters derived from contrast replenishment was evaluated using harmonic gray-scale (HGS) and harmonic power Doppler (HPD) imaging. In vitro experiments were performed in a flow model, whereas in vivo experiments were performed in 5 open-chest dogs. In each study, intermittent HGS and HPD images were acquired at various pulsing intervals during contrast infusion. A silicone pad was interposed between the transducer and target region to simulate attenuation conditions. Baseline-subtracted HGS and HPD signal intensities were measured with and without silicone pad, and myocardial blood flow parameters A and beta were calculated using contrast replenishment. Attenuation with HGS images could be offset by baseline subtraction, as baseline images provided the reference for attenuation. However, attenuation with HPD images could not be compensated for, as baseline signal intensity was theoretically 0. In HGS mode, silicone attenuation produced no significant decreases in A and beta. In HPD mode, however, A and beta were significantly decreased by silicone attenuation (A, P <.001; beta, P <.05). Compared with nonattenuated regions, myocardial blood flow parameters in attenuated regions are underestimated when HPD imaging is used. Baseline-subtracted HGS imaging may be useful to compensate for thoracic wall attenuation.

[Is blood squeezed out from the microcirculation soon after coronary occlusion?: real time myocardial contrast echocardiographic study]

BACKGROUND AND OBJECTIVES

The fate of blood trapped inside the myocardial microvessels after complete occlusion of the coronary artery has not been elucidated. Blood may be squeezed out by residual contraction even after coronary occlusion. The microcirculation was examined soon after coronary occlusion by real-time contrast echocardiography.

METHODS

Myocardial opacification in the short-axis view was examined during infusion of FS69 (Optison) using the Coherent Contrast Imaging method(SIEMENS Sequoia 512) in 17 open chest dogs. The left circumflex coronary artery was completely ligated for 15 sec and the video intensity (256 gray level) of the risk area was measured at end-systole of every 3 beats before and after ligation. Temporal deterioration of the wall motion was evaluated, defined as normokinesis, mild hypokinesis and severe hypokinesis, and akinesis. Changes in the video intensity during each stage of wall motion abnormalities were examined.

RESULTS

The video intensity of the risk area decreased significantly after coronary occlusion. Wall motion of the risk area deteriorated gradually after ligation, in which mild hypokinesis, severe hypokinesis and akinesis developed consecutively at 2.8 +/- 0.5, 5.4 +/- 0.5 and 7.8 +/- 0.8 sec after coronary ligation, respectively. The changes in video intensity during each stage of the wall motion abnormalities were small and not statistically significant, irrespective of severity of wall motion abnormalities.

CONCLUSIONS

These findings suggest that the blood remains in the vascular bed immediately after the coronary occlusion and is not squeezed out even if wall motion of the risk area continues.

Birth trends, survival improvements, and aging

"Decompositions of a change in the proportion of aged persons on the basis of the stable population theory [have] emphasized the contribution of fertility change. This study confirmed that cohort survival improvements largely contributed to changes in the proportion of aged persons and the average age since the late 1970s. Particularly, the cohort survival effects for those belonging to the age group 65+ at the time concerned was great." The geographical focus is on Japan.

A variable number of tandem repeats in the serotonin transporter gene does not affect the antidepressant response to fluvoxamine

A variable number of tandem repeats (VNTR) in the second intron of the serotonin transporter gene (STin2) has been studied in association with the susceptibility to affective disorders. Recently, it was reported that selective serotonin reuptake inhibitors were more effective in patients with major depressive disorder having the homozygous allele pair (12-copy/12-copy) of VNTR in the STin2 than in ones having other allele combinations. As the study had methodological problems, further studies are needed to confirm the above finding. Therefore, the authors investigated whether the allelic variation of VNTR in the STin2 was associated with the antidepressant response to fluvoxamine in 66 patients with major depressive disorder. Fluvoxamine was prescribed up to 200 mg/day in the dosing protocol for 6 weeks. The present study showed no significant association between the polymorphism of VNTR in the STin2 and the treatment response to fluvoxamine.

Association between TaqI A dopamine D2 receptor polymorphism and therapeutic response to bromperidol: a preliminary report

The relationship between TaqI A dopamine D2 receptor (DRD2) polymorphism and therapeutic response to bromperidol, a selective dopamine antagonist, was investigated in 30 acutely exacerbated schizophrenic inpatients. Patients were treated with bromperidol 6-18 mg/day for 3 weeks. Clinical symptoms were evaluated by the Brief Psychiatric Rating Scale (BPRS) before and 3 weeks after the treatment. The TaqI A genotypes were determined with the PCR method. There was no significant difference in the percentage improvement of total BPRS or 5-subgrouped symptoms (positive, negative, anxiety-depression, excitement and cognitive symptoms) after the 3-week treatment between the patients with A1 alleles (n=18) and those with no A1 allele (n=12). Although the present study is preliminary, it is suggested that the TaqI A DRD2 polymorphism is not associated with therapeutic response to bromperidol in schizophrenic patients.

Relationship between Taq1 A dopamine D2 receptor (DRD2) polymorphism and prolactin response to bromperidol

The dopamine D2 receptor (DRD2) gene has a Taq1 A restriction fragment length polymorphism yielding two alleles, A1 and A2. We have previously shown that female patients with the A1 allele show greater prolactin response to nemonapride, a selective antagonist for D2-like dopamine receptors, in schizophrenic patients. In the present study, the relationship between this polymorphism and prolactin response to bromperidol was investigated in 32 untreated schizophrenic inpatients (16 males, 16 females). The daily dose of bromperidol was fixed at 6 (n = 10), 12 (n = 13), or 18 mg (n = 9) during a 2-week treatment period. Taq1 A genotypes were determined by PCR method. Plasma prolactin concentration was measured by radioimmunoassay. Plasma concentration of bromperidol was measured by HPLC method. The subjects were divided into four subgroups by gender and the genotypes, i.e., 10 males and 11 females with the A1 allele, 6 males and 5 females with no A1 allele. The females with the A1 allele had the highest Delta prolactin (the change from the pretreatment concentration)/bromperidol concentration ratio among the other groups (P < 0.05). The present study thus suggests that female patients with the A1 allele show greater prolactin response to bromperidol, who may have a high risk for adverse effects associated with neuroleptic-induced hyperprolactinemia.

Lumbosacral transitional vertebrae and nerve-root symptoms

Transitional vertebrae (TV) may be one of the risk factors for lumbar disc herniation. It is not clear, however, whether the presence of TV can affect the development of nerve-root symptoms. Our aim was to clarify this relationship. A total of 501 patients with lumbar degenerative disease and nerve-root symptoms was studied in respect of their level and the presence of TV. As a control group, 508 patients without low back pain or nerve-root symptoms were studied to establish the incidence of TV. In patients with disc herniation, the incidence was statistically higher and the mean age lower in patients with TV than in those without. In most patients, the symptomatic disc level was just above the TV. Similarly, in those with stenosis of the spinal canal without spondylolisthesis, the symptomatic disc level was most commonly just above the TV.

Lumbosacral transitional vertebrae and nerve-root symptoms

Transitional vertebrae (TV) may be one of the risk factors for lumbar disc herniation. It is not clear, however, whether the presence of TV can affect the development of nerve-root symptoms. Our aim was to clarify this relationship. A total of 501 patients with lumbar degenerative disease and nerve-root symptoms was studied in respect of their level and the presence of TV. As a control group, 508 patients without low back pain or nerve-root symptoms were studied to establish the incidence of TV. In patients with disc herniation, the incidence was statistically higher and the mean age lower in patients with TV than in those without. In most patients, the symptomatic disc level was just above the TV. Similarly, in those with stenosis of the spinal canal without spondylolisthesis, the symptomatic disc level was most commonly just above the TV.

Immunohistochemical detection of 8-hydroxy-2'-deoxyguanosine in gallbladder epithelium of patients with pancreaticobiliary maljunction

OBJECTIVES

Pancreaticobiliary maljunction, an anomalous union of the pancreatic duct with the common bile duct, is a risk factor for biliary carcinoma. We hypothesized that, in patients with pancreaticobiliary maljunction, persistent regurgitation of pancreatic juice into the biliary tract induces oxidative DNA damage. We assessed the expression of an oxidative DNA base-modified product, 8-hydroxy-2'-deoxyguanosine, in gallbladder epithelium.

DESIGN

Eleven noncancerous gallbladders from patients with pancreaticobiliary maljunction, 12 gallbladder carcinomas from patients without pancreaticobiliary maljunction and 14 noncancerous gallbladders from patients without pancreaticobiliary maljunction (control) were studied.

METHODS

Immunohistochemistry was performed for 4-hydroxy-2-nonenal-modified protein (as a marker for lipid peroxidation), 8-hydroxy-2'-deoxyguanosine and p53 gene product.

RESULTS

Stronger cytoplasmic staining of 4-hydroxy-2-nonenal-modified protein was observed in the gallbladder epithelium from patients with pancreaticobiliary maljunction than in epithelium from gallbladder cancer patients or from control subjects with normal gallbladders. Clear, strong nuclear staining of 8-hydroxy-2'-deoxyguanosine was observed in the gallbladder epithelial cells from patients with pancreaticobiliary maljunction. Densitometric quantitation revealed significantly higher expression of 8-hydroxy-2'-deoxyguanosine in gallbladder epithelial cells from patients with pancreaticobiliary maljunction (index 27.3 +/- 3.1) than in cells from patients with gallbladder carcinoma (11.4 +/- 1.5; P < 0.05) or from control subjects with normal gallbladder (6.4 +/- 1.0; P < 0.05). Positivity of p53 was 27% in gallbladder epithelium associated with pancreaticobiliary maljunction, 75% in gallbladder carcinoma epithelium and 0% in control epithelium.

CONCLUSIONS

These results suggest that reactive oxygen species are produced in the gallbladder of patients with pancreaticobiliary maljunction and that oxidative DNA injury is related to carcinogenesis in these patients.

Effects of diclofenac and ketoprofen on nerve conduction velocity in experimental nerve root compression

STUDY DESIGN

The effects of diclofenac and ketoprofen on nerve conduction velocity in experimental nerve root compression were evaluated in a setup using an established pig model.

OBJECTIVE

To assess the effects of two potent nonsteroidal antiinflammatory drugs, diclofenac and ketoprofen, in experimental nerve root compression.

SUMMARY OF BACKGROUND DATA

Compression of spinal nerve roots is recognized to be of major etiologic importance for several common spinal pain syndromes. Secondary inflammatory changes, induced by microvascular permeability changes and leakage of inflammatory mediators into the endoneural tissue, have been proposed as important for the induction of spinal nerve root injury by chronic compression.

METHODS

This study involved 21 pigs. An ameroid constrictor was used to induce compression. Seven pigs were treated with daily intramuscular injections of diclofenac 3 mg/kg for 7 days. Seven other pigs were treated with daily intramuscular injections of ketoprofen 4 mg/kg. For a control, seven pigs did not receive any drug treatment. After 7 days, the pigs were reanesthetized, and the nerve conduction velocity in the compressed nerve root segments was determined.

RESULTS

The nerve conduction velocity was significantly higher (P < 0.05, Student's t test) in the pigs treated with diclofenac (50 +/- 16 m/second) than in the untreated pigs (32 +/- 15 m/second). The nerve conduction velocity also was significantly higher (P < 0.05) in the pigs treated with ketoprofen (59 +/- 16 m/second) than in the untreated pigs. There were no significant differences in nerve conduction velocity between pigs treated with ketoprofen and those treated with diclofenac.

CONCLUSIONS

The findings indicate that intramuscular administration of diclofenac or ketoprofen, both potent antiinflammatory drugs, may reduce nerve root dysfunction induced by compression of spinal nerve roots in an experimental pig model.

A successful clonazepam treatment without tolerance in a patient with spontaneous oral dyskinesia

There has been few reports on the effective treatment for SOD, which is phenomenologically similar to TD. A 66-year-old female with SOD was successfully treated by CNZ 2 mg/day. Even after one year of continuous treatment, tolerance, which is the major problem in the CNZ treatment for TD, did not develop. This report suggests that CNZ is effective at least for some patients with SOD.

Association of the TaqI A polymorphism of the dopamine D(2) receptor gene with predisposition to neuroleptic malignant syndrome

OBJECTIVE

The pathophysiology of neuroleptic malignant syndrome is mainly explained by a central hypodopaminergic state. The familial occurrence of neuroleptic malignant syndrome suggests the involvement of a genetic mechanism in the predisposition to the syndrome. Therefore, the authors examined the association between the TaqI A polymorphism of the dopamine D(2) receptor gene (DRD(2)), which alters DRD(2) density and function, and the development of neuroleptic malignant syndrome.

METHOD

The subjects were 15 psychiatric patients who had developed neuroleptic malignant syndrome (12 patients with schizophrenia and three with major depression) and 138 patients with schizophrenia who had never developed neuroleptic malignant syndrome. The TaqI A genotypes, A1 and A2 alleles, were determined by the polymerase chain reaction method.

RESULTS

The frequency of the A1 allele was significantly higher in the patients who had developed neuroleptic malignant syndrome (56.8%) than in the patients who had not (35.1%). The proportion of the A1 carrier was significantly higher in the patients with neuroleptic malignant syndrome (14 [93.3%] of 15 patients) than in those without the syndrome (79 [57.2%] of 138 patients).

CONCLUSIONS

These findings suggest that the TaqI A DRD(2) polymorphism is associated with the predisposition to neuroleptic malignant syndrome.

Calpains play a role in insulin secretion and action

Studies of the genetic basis of type 2 diabetes suggest that variation in the calpain-10 gene affects susceptibility to this common disorder, raising the possibility that calpain-sensitive pathways may play a role in regulating insulin secretion and/or action. Calpains are ubiquitously expressed cysteine proteases that are thought to regulate a variety of normal cellular functions. Here, we report that short-term (4-h) exposure to the cell-permeable calpain inhibitors calpain inhibitor II and E-64-d increases the insulin secretory response to glucose in mouse pancreatic islets. This dose-dependent effect is observed at glucose concentrations above 8 mmol/l. This effect was also seen with other calpain inhibitors with different mechanisms of action but not with cathepsin inhibitors or other protease inhibitors. Enhancement of insulin secretion with short-term exposure to calpain inhibitors is not mediated by increased responses in intracellular Ca2+ or increased glucose metabolism in islets but by accelerated exocytosis of insulin granules. In muscle strips and adipocytes, exposure to both calpain inhibitor II and E-64-d reduced insulin-mediated glucose transport. Incorporation of glucose into glycogen in muscle also was reduced. These results are consistent with a role for calpains in the regulation of insulin secretion and insulin action.

[Low back pain and sciatica]

In order to see the patients with low back pain and/or sciatica, it is most important to consider the pathophysiology of symptoms. We should know that the image findings such as X-ray and MRI do not always show the cause of symptom. Because degenerative changes in lumbar spine are common findings in asymptomatic group compared to symptomatic patients with low back pain and sciatica. According to pathophysiology (nerve root syndrome, cauda equina syndrome, facet syndrome, discogenic pain syndrome and intermittent claudication for low back pain), the treatment for low back pain and sciatica were described.

The -141C Ins/Del polymorphism in the dopamine D2 receptor gene promoter region is associated with anxiolytic and antidepressive effects during treatment with dopamine antagonists in schizophrenic patients

Previous studies have demonstrated a lower density of dopamine D2 receptor (DRD2) in subjects without Del alleles of the -141C Ins/Del polymorphism in DRD2 gene promoter region than in those with one or two Del alleles. The present study aimed to examine whether the -141C Ins/Del DRD2 promoter polymorphism is related to therapeutic response to selective DRD2 antagonists in the treatment of schizophrenia. Subjects consisted of 49 acutely exacerbated schizophrenic inpatients treated with bromperidol (30 cases, mean dose +/- SD: 11.4 +/- 4.8 mg/day) or nemonapride (19 cases, 18 mg/day). Clinical symptoms were evaluated by the Brief Psychiatric Rating Scale (BPRS) before and 3 weeks after the treatment. The -141C Ins/Del DRD2 genotypes, the Ins and Del alleles, were determined by a polymerase chain reaction method. Thirty-five patients were homozygous for the Ins allele and 14 were heterozygous for the Del and Ins alleles. The patients without Del allele showed a higher percentage of improvement in anxiety-depression symptoms than those with Del allele (58.5 +/- 44.5% versus 24.1 +/- 48.2%) after 3 weeks of treatment while percentage improvement in total BPRS or other subgrouped symptoms (positive, negative, excitement and cognitive symptoms) was similar between the two genotype groups. The present results suggest that the -141C Ins/Del DRD2 polymorphism is associated with anxiolytic and antidepressive effects of neuroleptic treatment in schizophrenic patients.

Effects of beraprost sodium on canine cauda equina function and blood flow using a chronic spinal cord compression model

Changes in blood flow after chronic compression were observed in 19 dogs after 10 mmHg compression for 1 week before and 1 hour after the intravenous administration of one of three doses of beraprost sodium (BPS; 30 ng x kg(-1) x min(-1), n = 7; 100 ng x kg(-1) x min(-1), n = 7; and 300 ng x kg(-1) x min(-1), n = 5). The speed of blood flow was calculated using a specially designed microscope equipped with a video camera. Dogs treated with BPS had lesser degrees of reduction in their nerve conduction velocity compared with controls. A vascular mechanism of injury likely explains why BPS-treated dogs had a lesser degree of reduction in their nerve conduction velocities compared with the control population.