Genetic variations and haplotypes of UGT1A4 in a Japanese population

Nineteen genetic variations, including 11 novel ones, were found in exon 1 and its flanking region of the UDP-glucuronosyltransferase (UGT) 1A4 gene from 256 Japanese subjects, consisting of 60 healthy volunteers, 88 cancer patients and 108 arrhythmic patients. These variations include -217T>G and -36G>A in the 5'-flanking region, 30G>A (P10P), 127delA (43fsX22; frame-shift from codon 43 resulting in the termination at the 22nd codon, codon 65), 175delG (59fsX6), 271C>T (R91C), 325A>G (R109G), and 357T>C (N119N) in exon 1, and IVS1+1G>T, IVS1+98A>G and IVS1+101G>T in the following intron. Among them, 127delA and 175delG can confer early termination of translation, resulting in an immature protein that probably lacks enzymatic activity. Variation IVS1+1G>T is located at a splice donor site and thus may lead to aberrant splicing. Since we did not find any significant differences in the frequencies of all the variations among the three subject groups, the data were analyzed as one group. The allele frequencies of the novel variations were 0.006 for IVS1+101G>T, 0.004 for 30G>A (P10P) and 357T>C (N119N), and 0.002 for the 8 other variations. In addition, the two known nonsynonymous single nucleotide polymorphisms (SNPs), 31C>T (R11W) and 142T>G (L48V), were found at 0.012 and 0.129 frequencies, respectively. The SNP 70C>A (P24T), mostly linked with 142T>G (L48V) in German Caucasians, was not detected in this study. Sixteen haplotypes were identified or inferred, and some haplotypes were confirmed by cloning and sequencing. It was shown that most of 142T>G (L48V) was linked with -219C>T, -163G>A, 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T, comprising haplotype *3a; haplotype *4a harbors 31C>T (R11W); 127delA (43fsX22) and 142T>G (L48V) were linked (haplotype *5a); 175delG (59fsX6) was linked with 325A>G (R109G) (*6a haplotype); and -219C>T, -163G>A, 142T>G (L48V), 271C>T (R91C), 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T comprised haplotype *7a. Our results provide fundamental and useful information for genotyping UGT1A4 in the Japanese and probably Asian populations.     

QT PRODACT: inter-facility variability in electrocardiographic and hemodynamic parameters in conscious dogs and monkeys

In safety pharmacology studies, the effect of a test compound on the electrocardiogram is routinely examined by using conscious dogs. However, the results may be widely variable. The monkey, on the other hand, has scarcely been used for such studies; and as yet, there have not been reported studies on monkeys conducted at several facilities with a standard protocol. In the present study, we examined inter-facility variabilities in electrocardiographic and hemodynamic parameters as described below. We analyzed the data from 8 facilities (9 test groups) on dogs and 5 facilities (7 test groups) on monkeys. This data was obtained from the studies employing the following standard protocol: dl-Sotalol or a vehicle (0.5 w/v% methylcellulose solution) was given to animals; and the PR interval, QRS duration, QT interval, heart rate, and mean blood pressure were determined time-sequentially before and after administration of the vehicle or dl-sotalol in each test group. dl-Sotalol produced a prolongation of the maximum mean QTcF interval in conscious dogs and QTcB interval in conscious monkeys by more than 10% in every test group. No difference in the corrected QT interval among the test groups was observed in dogs, but a difference was observed in monkeys.     

Inhibitory effect of thiopental on ultra-rapid delayed rectifier K+ current in H9c2 cells

Using the whole-cell voltage clamp technique, we investigated the effects of thiopental on membrane currents in H9c2 cells, a cell line derived from embryonic rat heart. Thiopental blocked a rapidly activating, very slowly-inactivating ultra-rapid type I(Kur)-like outward K(+) current in a concentration-dependent manner. The half-maximal concentration (IC(50)) of thiopental was 97 microM with a Hill coefficient of 1.2. The thiopental-sensitive current was also blocked by high concentrations of nifedipine (IC(50) = 9.1 microM) and 100 microM chromanol 293B, a blocker of slowly activating delayed rectifier K+ current (I(Ks)), but was insensitive to E-4031, an inhibitor of rapidly activating delayed rectifier K(+) current (I(Kr)). TEA (tetraethylammonium) at 5 mM and 4-AP (4-aminopiridine) at 1 mM reduced the K(+) current to 30.8 +/- 12.2% and 20.5 +/- 6.5% of the control, respectively. Using RT-PCR, we detected mRNAs of Kv2.1, Kv3.4, Kv4.1, and Kv4.3 in H9c2 cells. Among those, Kv2.1 and Kv3.4 have I(Kur)-type kinetics and are therefore candidates for thiopental-sensitive K(+) channels in H9c2 cells. This is the first report showing that thiopental inhibits I(Kur). This effect of thiopental may be involved in its reported prolongation of cardiac action potentials.     

Involvement of supraspinal imidazoline receptors and descending monoaminergic pathways in tizanidine-induced inhibition of rat spinal reflexes

The neuronal pathways involved in the muscle relaxant effect of tizanidine were examined by measurement of spinal reflexes in rats. Tizanidine (i.v. and intra-4th ventricular injection) decreased the mono- and disynaptic (the fastest polysynaptic) reflexes (MSR and DSR, respectively) in non-spinalized rats. Depletion of central noradrenaline by 6-hydroxydopamine abolished the depressant effect of tizanidine on the MSR almost completely and attenuated the effect on the DSR. Co-depletion of serotonin by 5,6-dihydroxytryptamine and noradrenaline resulted in more prominent attenuation of tizanidine-induced inhibition of the DSR. Supraspinal receptors were then studied using yohimbine- and some imidazoline-receptor ligands containing an imidazoline moiety. Idazoxan (I1, I2, I3, and alpha2), efaroxan (I1, I3, and alpha2), and RX821002 (I3 and alpha2), but not yohimbine, an alpha2-adrenergic receptor antagonist with no affinity for I receptors, antagonized the inhibitory effects of tizanidine. Thus, supraspinal I receptors (most likely I3) and descending monoaminergic influences are necessary for tizanidine-induced inhibition of spinal segmental reflexes.     

Nanotechnology, nanomedicine, and the development of new, effective therapies for cancer

Cancer is the leading cause of death in the United States among people younger than 85 years, and for the first time has surpassed heart disease as the number one killer. This worrisome statistic has resulted not from an increase in the incidence of cancer, but because deaths from heart disease have dropped nearly in half while the number of cancer-related deaths has remained about the same. This fact accentuates the need for a new generation of more effective therapies for cancer. In this review, the development of new therapies will be discussed in the context of advances in nanotechnologies related to cancer detection, analysis, diagnosis, and therapeutic intervention. First, several nanoanalytical methods, such as the use of quantum dots in detection and imaging of cancer, will be described. These techniques will be essential to the process of precisely describing cancer at the level of the cell and whole organism. Second, examples of how nanotechnologies can be used in the development of new therapies will be given, including methods that might allow for more efficient and accurate drug delivery and rationally designed, targeted drugs. Finally, a new initiative--the National Cancer Institute Alliance for Nanotechnology in Cancer--will be described and discussed with respect to the scientific issues, policies, and funding.     

Radical formation by grinding of commercial tablets according to hospital and pharmacy prescription

We examined mechanoradical formation in the grinding process of commercial tablets using electron spin resonance (ESR). Mechanoradicals were detected in all tested samples (23 types of commercial tablets) when the ball-milling of tablets was conducted under anaerobic conditions and some were fairly stable even in air. Thus the grinding may cause changes in the physicochemical properties of ingredients included in commercial tablets. Because high quality is demanded in pharmaceuticals, these results suggest more caution should be taken in the grinding of commercial tablets in hospitals and pharmacies.     

Centrally mediated antihyperalgesic and antiallodynic effects of zonisamide following partial nerve injury in the mouse

Some antiepileptic drugs are used clinically to relieve neuropathic pain. We have evaluated the effects and investigated the possible mechanisms of action of zonisamide, an antiepileptic drug, on thermal hyperalgesia and tactile allodynia in a murine chronic pain model that was prepared by partial ligation of the sciatic nerve. Subcutaneously administered zonisamide (10 and 30 mg/kg) produced antihyperalgesic and antiallodynic effects in a dose-dependent manner; these effects were manifested by elevation of the withdrawal threshold in response to a thermal (plantar test) or mechanical (von Frey) stimulus, respectively. Similar analgesic effects were obtained in both the plantar and von Frey tests when zonisamide was injected either intracerebroventricularly (i.c.v., 10 and 30 μg) or intrathecally (i.t., 10 and 30 μg). It is thought that this elevation of the thermal and mechanical withdrawal thresholds after local injection of zonisamide is not generated secondarily via impaired motor activity, since zonisamide (30 μg, i.c.v. or i.t.) did not affect locomotor activity, as assessed in sciatic-nerve-ligated mice. Moreover, the nitric oxide synthase inhibitor L-NAME, when injected either i.c.v. or i.t., potentiated the analgesic effects of zonisamide. In contrast, neither i.c.v. nor i.t. zonisamide produced antinociceptive effects against acute thermal and mechanical nociception in non-ligated mice. Together, following peripheral nerve injury, it appears that zonisamide produces centrally mediated antihyperalgesic and antiallodynic effects partly via the blockade of nitric oxide synthesis.     

Association of HER-2 overexpression with prognosis in nonsmall cell lung carcinoma: a metaanalysis

BACKGROUND: Prognostic implications of overexpression of the HER-2 gene in nonsmall cell lung carcinoma (NSCLC) are a matter of controversy. Many conflicting results have been reported from different laboratories. METHODS: A metaanalysis of published studies was performed for this quantitative review of the effects of HER-2 overexpression on survival among patients with NSCLC. Of 44 articles initially selected, 20 articles fulfilled eligibility criteria. DerSimonian-Laird random effects analysis was used to estimate the effects of HER-2 overexpression on survival differences (the survival rate among patients without HER-2 overexpression minus the survival rate among patients with HER-2 overexpression) at endpoints of 1 years, 3 years, and 5 years after resection of NSCLC. RESULTS: In total, 2579 patients were included in the final analysis. Overall, HER-2 positivity differed according to histologic type and included 38% of patients with adenocarcinoma, 16% of patients with squamous cell carcinoma, and 18% of patients with large cell carcinoma (P < 0.0001). The combined survival differences in patients with NSCLC at 1 year, 3 years, and 5 years, respectively, were 2.7% (95% confidence interval [95% CI], 1.3-6.7%; P = 0.1787), 15.2% (95% CI, 5.8-24.5%; P = 0.0015), and 16.4% (95% CI, 7.9-14.8%; P = 0.0001), suggesting significant poorer survival at 3 years and 5 years among patients with HER-2 overexpression. In patients with adenocarcinoma, the combined survival difference at 5 years was 26.0% (95% CI, 16.0-36.1%; P < 0.0001), suggesting a particularly strong survival impact for HER-2 overexpression. CONCLUSIONS: A significant, unfavorable prognostic effect of HER-2 overexpression in NSCLC was evident from the metaanalysis. However, because several studies that found no significant difference were excluded by the current eligibility criteria, caution is needed in interpreting the results.     

Usefulness of extension of disease as a prognostic factor in relapsed prostate cancer patients of stage D

OBJECTIVE: The prognosis of prostate cancer has been evaluated by clinical stage or pathological grade. PSA parameters including PSA density and PSA doubling time have not always precisely reflected the prognosis of prostate cancer. The aim of this study was to evaluate PSA parameters and extension of disease (EOD) grade as prognostic factors for relapsed prostate cancer. METHODS: The relationship between PSA parameters or EOD grade, and survival of 29 stage D patients with relapsed prostate cancer after initial hormone therapy was examined. RESULTS: Only EOD grade was an independent prognostic factor, even for cause-specific survival period and survival period after relapse. CONCLUSION: EOD grade was a significant prognostic factor, and in particular, very useful as a prognostic factor for patients with bone metastasis. PSA value was not always associated with tumor volume, and therefore it is not an independent prognostic factor.     

Comparison of radical retropubic prostatectomy under combined lumbar spinal and epidural anesthesia with that under combined general and epidural anesthesia

PURPOSE: To evaluate the efficacy of combined lumbar spinal and epidural (CLSE) anesthesia in retropubic radical prostatectomy. MATERIALS AND METHODS: Twenty consecutive patients who underwent radical retropubic prostatectomy by a single surgeon (H.K.) under CLSE anesthesia from July of 2003 to February of 2004 were selected as subjects. They were compared with 20 consecutive patients who underwent radical retropubic prostatectomy performed by the same surgeon under combined general and epidural (CGE) anesthesia from April to December of 2002. Both periods were carefully selected to exclude radical prostatectomies with intraoperative complications to evaluate genuine effects of anesthesia. For lumbar spinal anesthesia, 0.5% hyperbaric bupivacaine hydrochloride or 0.5% hyperbaric tetracaine hydrochloride (dissolved in a 10% glucose solution) was used. An epidural tube was inserted for both lumbar spinal anesthesia and general anesthesia mainly for the purpose of controlling a pain after operation. RESULTS: Intraoperative blood loss was significantly less in the CLSE anesthesia group compared with CGE anesthesia group (p = 0.024). Postoperative water drinking was started at 0.4 days (average) for CLSE anesthesia and at 1.1 days (average) for CGE anesthesia (p < 0.0001). Postoperative diet was begun at 0.7 days (average) for CLSE anesthesia and at 1.5 days (average) for CGE anesthesia (p < 0.0001). Compared with the CLSE anesthesia group, the mean of the highest intraoperative mean blood pressure was significantly higher in the CGE anesthesia group (p = 0.002). CONCLUSION: Intraoperative blood loss was less, intraoperative change in blood pressure was less and recovery of postoperative intestinal peristalsis was earlier in patients who underwent prostatectomy under CLSE anesthesia than in patients who underwent prostatectomy under CGE anesthesia. We believe that prostatectomy under CLSE anesthesia is more advantageous than prostatectomy under CGE anesthesia.