Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Ceramide limits phosphatidylinositol-3-kinase C2β-controlled cell motility in ovarian cancer: potential of ceramide as a metastasis-suppressor lipid

Targeting cell motility, which is required for dissemination and metastasis, has therapeutic potential for ovarian cancer metastasis, and regulatory mechanisms of cell motility need to be uncovered for developing novel therapeutics. Invasive ovarian cancer cells spontaneously formed protrusions, such as lamellipodia, which are required for generating locomotive force in cell motility. Short interfering RNA screening identified class II phosphatidylinositol 3-kinase C2β (PI3KC2β) as the predominant isoform of PI3K involved in lamellipodia formation of ovarian cancer cells. The bioactive sphingolipid ceramide has emerged as an antitumorigenic lipid, and treatment with short-chain C6-ceramide decreased the number of ovarian cancer cells with PI3KC2β-driven lamellipodia. Pharmacological analysis demonstrated that long-chain ceramide regenerated from C6-ceramide through the salvage/recycling pathway, at least in part, mediated the action of C6-ceramide. Mechanistically, ceramide was revealed to interact with the PIK-catalytic domain of PI3KC2β and affect its compartmentalization, thereby suppressing PI3KC2β activation and its driven cell motility. Ceramide treatment also suppressed cell motility promoted by epithelial growth factor, which is a prometastatic factor. To examine the role of ceramide in ovarian cancer metastasis, ceramide liposomes were employed and confirmed to suppress cell motility in vitro. Ceramide liposomes had an inhibitory effect on peritoneal metastasis in a murine xenograft model of human ovarian cancer. Metastasis of PI3KC2β knocked-down cells was insensitive to treatment with ceramide liposomes, suggesting specific involvement of ceramide interaction with PI3KC2β in metastasis suppression. Our study identified ceramide as a bioactive lipid that limits PI3KC2β-governed cell motility, and ceramide is proposed to serve as a metastasis-suppressor lipid in ovarian cancer. These findings could be translated into developing ceramide-based therapy for metastatic diseases.

Eukaryotic elongation factor 2 kinase controls proliferation and migration of vascular smooth muscle cells

AIM

Eukaryotic elongation factor 2 kinase (eEF2K), also known as calmodulin (CaM)-dependent protein kinase (CaMK) III, is a unique member of CaMK family protein. We have recently found that expression of eEF2K protein increased in mesenteric artery from spontaneously hypertensive rats. As pathogenesis of hypertension is in part regulated by vascular structural remodelling via proliferation and migration of vascular smooth muscle cells (SMCs), we tested the hypothesis that eEF2K controls SMCs proliferation and migration.

METHODSAND RESULTS

In rat mesenteric arterial SMCs, an eEF2K inhibitor, A-484954 (10 μm), significantly inhibited platelet-derived growth factor (PDGF)-BB (10 ng mL(-1) )-induced SMCs proliferation as determined by a cell counting and bromodeoxyuridine incorporation assay. PDGF-BB (10 ng mL(-1) )-induced SMCs migration was significantly inhibited by A-484954 (10 μm) as determined by a Boyden chamber assay. A-484954 (10 μm) significantly inhibited PDGF-BB (10 ng mL(-1) )-induced phosphorylation of eEF2K, extracellular signal-regulated kinase (ERK), Akt, p38 and heat-shock protein (HSP) 27 as determined by Western blotting. It was confirmed that a CaM inhibitor, W-7 (50 μm), inhibited PDGF-BB (10 ng mL(-1) )-induced phosphorylation of eEF2K. In an ex vivo mesenteric arterial ring assay, 10% foetal bovine serum-induced SMCs outgrowth was significantly inhibited by A-484954 (10 μm).

CONCLUSION

We for the first time revealed that eEF2K mediates PDGF-BB-induced SMCs proliferation and migration through activating ERK, Akt, p38 and HSP27 signals in a CaM-dependent manner. Our results suggest eEF2K as a novel pharmaceutical target for the prevention of hypertensive cardiovascular diseases.

Brain-derived neurotrophic factor promotes angiogenic tube formation through generation of oxidative stress in human vascular endothelial cells

AIM

Brain-derived neurotrophic factor (BDNF), a major type of neurotrophins, plays a role in the regulation of synaptic function. Recent studies suggest that BDNF promotes angiogenesis through its specific receptor, tropomyosin-related kinase B (TrkB). However, the detailed mechanisms for this still remain to be determined. Reactive oxygen species (ROS) generation contributes to the regulation of angiogenesis. Thus, we investigated the mechanisms by which BDNF regulates angiogenesis with focusing on ROS in cultured human vascular endothelial cells (ECs).

METHODS AND RESULTS

In human umbilical vein ECs, BDNF increased ROS generation as measured fluorometrically using 2' 7'-dichlorofluorescein diacetate as well as NADPH oxidase (NOX) activity as measured by lucigenin assay. BDNF-induced ROS generation and NOX activity were inhibited by K252a, a TrkB receptor inhibitor. BDNF induced phosphorylation of p47 phox, a regulatory component of NOX, which was inhibited by K252a as measured by Western blotting. BDNF increased angiogenic tube formation in ECs, which was completely inhibited by K252a or gp91ds-tat, a NOX inhibitor. BDNF caused Akt phosphorylation in ECs, which was inhibited by K252a or gp91ds-tat.

CONCLUSION

The present results for the first time demonstrate that BDNF induces NOX-derived ROS generation through activation of p47 phox in a TrkB receptor-dependent manner, which leads to the promotion of angiogenic tube formation possibly via Akt activation.

Observation of quadrupole helix chirality and its domain structure in DyFe3(BO3)4

Resonant X-ray diffraction (RXD) uses X-rays in the vicinity of a specific atomic absorption edge and is a powerful technique for studying symmetry breaking by motifs of various multipole moments, such as electric monopoles (charge), magnetic dipoles (spin) and electric quadrupoles (orbital). Using circularly polarized X-rays, this technique has been developed to verify symmetry breaking effects arising from chirality, the asymmetry of an object upon its mirroring. Chirality plays a crucial role in the emergence of functionalities such as optical rotatory power and multiferroicity. Here we apply spatially resolved RXD to reveal the helix chirality of Dy 4f electric quadrupole orientations and its domain structure in DyFe3(BO3)4, which shows a reversible phase transition into an enantiomorphic space-group pair. The present study provides evidence for a helix chiral motif of quadrupole moments developed in crystallographic helix chirality.

Identification and characterization of a novel aac(6')-Iag associated with the blaIMP-1-integron in a multidrug-resistant Pseudomonas aeruginosa

In a continuing study from Dec 2006 to Apr 2008, we characterized nine multi-drug resistant Pseudomonas aeruginosa strains isolated from four patients in a ward at the Hiroshima University Hospital, Japan. Pulsed-field gel electrophoresis of SpeI-digested genomic DNAs from the isolates suggested the clonal expansion of a single strain; however, only one strain, NK0009, was found to produce metallo-β-lactamase. PCR and subsequent sequencing analysis indicated NK0009 possessed a novel class 1 integron, designated as In124, that carries an array of four gene cassettes: a novel aminoglycoside (AG) resistance gene, aac(6')-Iag, blaIMP-1, a truncated form of blaIMP-1, and a truncated form of aac(6')-Iag. The aac(6')-Iag encoded a 167-amino-acid protein that shows 40% identity with AAC(6')-Iz. Recombinant AAC(6')-Iag protein showed aminoglycoside 6'-N-acetyltransferase activity using thin-layer chromatography (TLC) and MS spectrometric analysis. Escherichia coli carrying aac(6')-Iag showed resistance to amikacin, arbekacin, dibekacin, isepamicin, kanamycin, sisomicin, and tobramycin; but not to gentamicin. A conjugation experiment and subsequent Southern hybridization with the gene probes for blaIMP-1 and aac(6')-Ig strongly suggested In124 is on a conjugal plasmid. Transconjugants acquired resistance to gentamicin and were resistant to virtually all AGs, suggesting that the In124 conjugal plasmid also possesses a gene conferring resistance to gentamicin.

Quantification of interferon, interleukin, and Toll-like receptor 7 mRNA in quail splenocytes using real-time PCR

Japanese quail (Coturnix japonica) are farmed worldwide as poultry. Quail have been used as experimental animals in various scientific fields, but their immunological characteristics have not been well characterized. In this study, to develop a method for analyzing the innate immune response of quail to infectious pathogens, we determined the nucleotide sequences of major interleukins (IL) and Toll-like receptor (TLR)-7 of quail and developed quantitative real-time PCR assays. The nucleotide sequences of quail IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12a, IL-12b, IL-13, IL-18, and TLR-7 were determined based on the sequences of the chicken genes. Specific primers for each of these genes and previously reported interferon (IFN)-α, IFN-γ, and IL-2 genes were designed for quantitative real-time PCR. Standard curves for quantification were established using serial dilutions of external standard plasmids containing real-time PCR products. Then, real-time PCR was performed to monitor the kinetics of quail immune-related gene expression induced in splenocytes stimulated with concanavalin A. After amplification, the r(2) values of the standard curves for all target genes were above 0.980. Melting analysis of real-time PCR revealed specific amplification of each gene that could be visualized clearly as a single peak of melting temperature in a melt peak chart. These data show that the mRNA expressions of quail immune-related genes can be accurately quantified using this real-time PCR assay. In this study, we showed the nucleotide sequences of several quail cytokine mRNA and constructed the quantitative real-time PCR for quail immune-related genes.

Magnetic phase diagram of CuO via high-resolution ultrasonic velocity measurements

High-resolution ultrasonic velocity measurements have been used to determine the temperature-magnetic-field phase diagram of the monoclinic multiferroic CuO. A new transition at T(N3)=230 K, corresponding to an intermediate state between the antiferromagnetic noncollinear spiral phase observed below T(N2)=229.3 K and the paramagnetic phase, is revealed. Anomalies associated with a first order transition to the commensurate collinear phase are also observed at T(N1)=213 K. For fields with B || b, a spin-flop transition is detected between 11 T-13 T at lower temperatures. Moreover, our analysis using a Landau-type free energy clearly reveals the necessity for an incommensurate collinear phase between the spiral and the paramagnetic phase. This model is also relevant to the phase diagrams of other monoclinic multiferroic systems.

Interferon-gamma release assay for diagnosing Mycobacterium tuberculosis infections in patients with systemic lupus erythematosus

Our aim was to analyze the performance of an interferon-gamma release assay, QuantiFERON-TB Gold (QFT-2G), for diagnosing Mycobacterium tuberculosis (MTB) infection in patients with systemic lupus erythematosus (SLE). We performed the QFT-2G and tuberculin skin test (TST) in 71 SLE patients. The QFT-2G results of 279 patients with other connective tissue diseases (CTD) and 35 healthy controls were analyzed. Of the 71 SLE patients, two (2.8%) were positive and 46 (64.8%) were negative by QFT-2G. All SLE patients had no evidence of active MTB infection, apart from one. QFT-2G produced a significantly higher number of indeterminate results in patients with SLE (23/71, 32.4%) compared with those with other CTD (5.7%) or healthy controls (0%) ( p < 0.0001 and p < 0.0001). Decreased lymphocyte counts and high SLEDAI scores in SLE patients were shown to be risk factors for indeterminate results by multivariate analysis ( p = 0.02 and p = 0.04). Among all patients with CTD, SLE itself and lymphocytopenia were found to be independent risks for indeterminate results ( p = 0.00000625 and p = 0.000107). In conclusion, QFT-2G may have more potential to assist in the diagnosis of active and latent MTB infection than TST in SLE patients. However, because of the high frequency of indeterminate results, caution must be used when interpreting the results of QFT-2G among SLE patients, especially those who have parallel or subsequent flares.

The development of a non-contact screening system for rapid medical inspection at a quarantine depot using a laser Doppler blood-flow meter, microwave radar and infrared thermography

In order to conduct fast screening of passengers with infections such as severe acute respiratory syndrome (SARS) or pandemic influenza at a quarantine depot, we developed a non-contact screening system with self-produced program to conduct a human screening within five seconds, via a linear discriminant function from non-contact derived variables, i.e. palmer pulse derived from a laser Doppler blood-flow meter, respiration rate determined by a 10-GHz microwave radar, and facial temperature measured by thermography. The system evaluation was conducted on seven healthy male subjects (23 +/- 1 years). In order to achieve a pseudo-infection condition, the subjects maintained an ergometer exercise load (100 W, 10 minutes). Before (normal condition) and after (pseudo-infection condition) exercise, a significant linear discriminant function (p < 0.001) was determined to distinguish pseudo-infection condition from normal condition (Mahalanobis D-square = 20.3, classification error rate <5%). The proposed system appears promising for future application in fast screening of infection at a quarantine depot.

Development of a non-contact screening system for rapid medical inspection at a quarantine depot using a laser Doppler blood-flow meter, microwave radar and infrared thermography

In order to conduct fast screening of passengers with infections such as severe acute respiratory syndrome (SARS) or pandemic influenza at a quarantine depot, we developed a non-contact screening system with a self-produced program to conduct a human screening within five seconds, via a linear discriminant function from non-contact derived variables, i.e. palmer pulse derived from a laser Doppler blood-flow meter, respiration rate determined by a 10-GHz microwave radar, and facial temperature measured by a thermography. The system evaluation was conducted on seven healthy male subjects (23+1 years). In order to achieve a pseudo-infection condition, the subjects maintained an ergo-meter exercise load (100 W, 10 minutes). Before (normal condition) and after (pseudo-infection condition) exercise, a significant linear discriminant function (p50.001) was determined to distinguish the pseudo-infection condition from the normal condition (Mahalanobis D-square 1/4 20.3, classification error rate55%). The proposed system appears promising for future application in fast screening of infection at a quarantine depot.

Prevalence of painful bladder syndrome (PBS) symptoms in adult women in the general population in Japan

AIMS

The aim of this study was to clarify the prevalence of painful bladder syndrome (PBS) symptoms in adult women in the general population in Japan.

METHODS

Web-based survey through an internet-based market research company that enrolled 561,631 men and women in Japan was conducted from January 9 to January 11, 2007. After the women allocated to four age groups; 20s, 30s, 40s, and 50s or older, a total of 80,367 women, comprising an almost equal number from each age group, were then randomly invited to participate. The O'Leary and Sant symptom index was used as the questionnaire. The following classification was defined on the basis of the total points score: 0 to 3 points for negligible PBS symptoms, 4 to 6 points for mild symptoms, 7 to 11 points for moderate symptoms, and 12 to 20 points for severe symptoms. A category of possible cases of PBS was defined as severe PBS symptoms including nocturia (twice or more) and pain (2 points or more).

RESULTS

A total of 32,074 women ranging in age from 20 to 88 years participated. 76.6% of respondents had negligible PBS symptoms, 17.3% had mild symptoms, 5.6% had moderate symptoms, and 0.5% had severe symptoms, respectively. The incidence rate of women with possible cases of PBS was 0.265% (85/32,074).

CONCLUSIONS

Comparison with previous reports revealed no difference in the prevalence of PBS symptom in adult women in the general population between Japan and Western countries.

Development of the human retroperitoneal fasciae

INTRODUCTION

Although the renal fascia (RF), ureteral sheath, lateroconal fascia (LF) and hypogastric nerve are critical landmarks for retroperitoneal surgery, their laminar relationships require clarification.

MATERIALS AND METHODS

Horizontal sections (hematoxylin-eosin staining) of human fetuses at two different developmental stages [9-12 (3 fetuses, crown-rump length, CRL 40-65 mm) and 20-25 weeks of gestation (9 fetuses, CRL 152-220 mm)] were compared.

RESULTS

In the early-stage group, the pararenal space had already formed between the posterior RF and the transversalis fascia (TF). The anterior RF extended along the peritoneum and often fused with the latter. In the late-stage group, the posterior RF extended inferomedially toward the anterior aspect of the aorta and inferior vena cava. However, at the level of the renal hilus, the posterior RF was connected with vascular sheaths of the great vessels. The LF was seen developing as a fasciculation of the multilaminar structure in the pararenal space. However, on the posterolateral side of the colon after retroperitoneal fixation, the fusion fascia of the peritoneum could also be identified as LF.

CONCLUSIONS

A common sheath for ureters and hypogastric nerves appeared to be likely on the inferior side of the kidney. The LF did not appear to be a primary structure such as the RF, but a result of secondary mechanical stress due to fatty tissue developing earlier along the TF than in the perirenal space. However, the suggested similarity between LF and fusion fascia in the plane occupied was a likely cause for misinterpreting the laminar configurations during surgery.

Evaluation of the inhibitory and induction potential of YM758, a novel If channel inhibitor, for human P450-mediated metabolism

This study was designed to examine the in vitro metabolism of YM758, a novel cardiovascular agent, and to evaluate its potential to cause drug interactions and induction of CYP isozymes. After incubation with pooled human liver microsomes, YM758 was converted to two major metabolites (AS2036313-00, and YM-394111 or YM-394112). The formation of AS2036313-00, and YM-394111 or YM-394112 were mediated by CYP2D6 and CYP3A4, respectively, which was elucidated by using a bank of human liver microsomes and recombinant CYP enzymes in combination with the utilization of typical substrates and inhibitors. The Ki values of YM758 for midazolam, nifedipine, and metoprolol metabolism ranged from 59 to 340 microM, being much higher than the YM758 concentration in human plasma. The formation of AS2036313-00, and YM-394111 or YM-394112 was inhibited by quinidine and ketoconazole with Ki values of 140 and 0.24 microM, respectively, which indicates that YM758 metabolism may be affected by coadministration of strong CYP2D6 and 3A4 inhibitors in vivo, given the clinical plasma concentrations of quinidine and ketoconazole. After human hepatocytes were exposed to 10 microM YM758, microsomal activity and mRNA level for CYP1A2 were not induced while those for CYP3A4 were slightly induced. The tested concentration was much higher than that in human plasma, which suggests that the induction potential of YM758 is also negligible.

Five-year longitudinal effect of radical perineal prostatectomy on health-related quality of life in Japanese men, using general and disease-specific measures

OBJECTIVE

To investigate the longitudinal alteration of health-related quality of life (HRQL) up to 5 years after radical perineal prostatectomy (RPP) among Japanese patients with localized prostate cancer.

PATIENTS AND METHODS

In all, 194 patients who had RPP were included in this longitudinal survey. The validated RAND 36-Item Health Survey (SF-36) and the University of California, Los Angeles Prostate Cancer Index (UCLA-PCI) were used to evaluate the HRQL.

RESULTS

Among the UCLA-PCI urinary domains, urinary function scores decreased at 3 months after RPP, but they increased 6 months after RPP. Likewise, urinary bother showed a transient decrease at 3 months, but had returned to the baseline level 6 months after RPP. Sexual function (SF) was drastically decreased at 3 months after RPP, but had slightly increased 1 year after RPP. Patients who had a nerve-sparing (NS) RPP showed better SF-related HRQL than those who did not at 6 months after RPP. This favourable alteration involving SF-related HRQL was closely associated with the NS procedure, but not with the patient age. Multivariate analysis showed that later recovery of SF was essentially related to the use of NS RPP, while early recovery of sexual bother was closely related to the patient age.

CONCLUSIONS

Our results confirmed the positive effect of RPP on the long-term HRQL in Japanese patients. Although NS surgery conferred the benefit of the recovery of SF, older Japanese patients were not greatly concerned about their decreased SF-related HRQL. The current results provide primary evidence for predicting the alteration of HRQL and understanding the effect of patient age and NS surgery on HRQL after RPP.

Immunohistochemical analysis of Reg IV in urogenital organs: Frequent expression of Reg IV in prostate cancer and potential utility as serum tumor marker

Regenerating islet-derived family, member 4 (Reg IV) is a candidate marker for cancer and inflammatory bowel disease and is associated with neuroendocrine and intestinal differentiation. We have reported that 14% of prostate cancer (PCa) cases are positive for Reg IV by immunohistochemistry. In the present study, we performed immunohistochemical analysis of Reg IV in other major urological cancers, including 101 renal cell carcinoma (RCC), and 95 urothelial carcinoma (UC) of urinary bladder by immunohistochemistry. We also investigated neuroendocrine differentiation by chromogranin A and synaptophysin staining along with intestinal differentiation by MUC2 staining. Immunohistochemical analysis of Reg IV revealed no expression of Reg IV in RCC, and only one case (1%) of UC expressed Reg IV. Neither neuroendocrine nor intestinal differentiation was found in RCC. Among 95 UC cases, neuroendocrine differentiation was detected in 13 cases (14%), and intestinal differentiation was observed in 33 cases (35%). In one Reg IV-positive UC case, MUC2 staining was observed. Since Reg IV expression was frequently found in PCa, we also measured Reg IV levels in sera from patients with PCa by enzyme-linked immunosorbent assay. The serum Reg IV concentration in PCa patients (n=38, mean +/- SE, 1.69+/-0.16 ng/ml) was significantly higher than that in control individuals (n=40, 1.28+/-0.11 ng/ml, P=0.0199, Mann-Whitney U test). The sensitivity and specificity for detection of PCa were 34% (13/38) and 90% (36/40), respectively. These results suggest that among major urologic cancers, Reg IV is expressed frequently in PCa, and that serum Reg IV represents a novel biomarker for PCa.

Reg IV is an independent prognostic factor for relapse in patients with clinically localized prostate cancer

Regenerating islet-derived family, member 4 (REG4, which encodes Reg IV) is a candidate marker for cancer and inflammatory bowel disease. We investigated the potential prognostic role of Reg IV immunostaining in clinically localized prostate cancer (PCa) after radical prostatectomy. Immunohistochemical staining of Reg IV was performed in 98 clinically localized PCa tumors obtained during curative radical prostatectomy. Intestinal and neuroendocrine differentiation was investigated by MUC2 and chromogranin A immunostaining, respectively. The prognostic significance of immunohistochemical staining for these factors on prostate-specific antigen (PSA)-associated recurrence was assessed by Kaplan-Meier analysis and a Cox regression model. Phosphorylation of the epidermal growth factor receptor (EGFR) by Reg IV was analyzed by Western blot. In total, 14 (14%) of the 98 PCa cases were positive for Reg IV staining. Reg IV positivity was observed frequently in association with MUC2 (P = 0.0182) and chromogranin A positivity (P = 0.0012). Univariate analysis revealed that Reg IV staining (P = 0.0004), chromogranin A staining (P = 0.0494), Gleason score (P < 0.0001) and preoperative PSA concentration (P = 0.0167) were significant prognostic factors for relapse-free survival. Multivariate analysis indicated that Reg IV staining (P = 0.0312), Gleason score (P = 0.0014) and preoperative PSA concentration (P = 0.0357) were independent predictors of relapse-free survival. In the LNCaP cell line, EGFR phosphorylation was induced by the addition of Reg IV-conditioned medium. These results suggest that Reg IV expression is an independent prognostic indicator of relapse after radical prostatectomy.

Identification of metabolites of [14C]zonampanel, an α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor antagonist, following intravenous infusion in healthy volunteers

This study determined the pharmacokinetics, metabolism and excretion of an a-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor antagonist zonampanel monohydrate (YM872) after intravenous infusion of [14C]YM872 at 1 mg kg-1 h-1 for 2 h to four healthy male volunteers. Mean pharmacokinetic parameters of unchanged YM872 were 0.78 h for terminal half-life, 25.9 l h-1 for total clearance, 22.9 l h-1 for renal clearance, and 15.6 l for volume of distribution at steady-state. Urinary excretion of radioactivity accounted for 94.9% of the dose, and faecal excretion for only 0.5% of the dose. Measurement of YM872 concentrations by a high-performance liquid chromatography (HPLC)-ultraviolet method and radiometric HPLC metabolite profiling revealed that almost all of [14C]YM872 was excreted unchanged in the urine and that unchanged [14C]YM872 was the major circulating [14C] component in the plasma. Two minor metabolites, H1 and H2, detected in the urine and identified as the same chemical structures as those of the rat urinary metabolites, have a hydroxyamino group and an amino group, respectively, which were probably formed by reduction of the nitro group of YM872. These results show that virtually all of the administered YM872 remains unchanged, with urinary excretion representing the major elimination pathway. The high renal clearance implies tubular secretion of this drug.

Tissue distribution of YM758, a novel If channel inhibitor, in pregnant and lactating rats

In this study the tissue distribution of radioactivity in pregnant and lactating rats was investigated by quantitatively determining radioactivity concentrations and by whole-body autoradioluminograms after a single oral administration of 14C-YM758. In addition, the transfer of radioactivity into the reproductive tissues, foetus, and milk is discussed in terms of the localization of transporters in syncytiotrophoblast and mammary gland. The radioactivity concentrations in the liver were the highest of all the tissues and organs tested at all the sampling times. The radioactivity in main tissues (liver and kidney), including reproductive tissues (amniotic fluid, placenta, ovary, and uterus), was not retained for a long time, as in the plasma. The tissue/plasma (T/P) ratio of radioactivity in the foetus was below 1.0, which might be due to Mdr1-mediated export of YM758 into blood via the blood-placenta barrier since YM758 is a substrate for hMDR1, not for hBCRP/rBcrp. The T/P ratio of radioactivity in the maternal milk 1 and 4 h after oral administration of 14C-YM758 was 7.2 and 11.0, respectively. To understand better the distribution of new drugs into the reproductive tissues/milk, and to interpret further the results of reproductive safety studies for drug development, the contribution of transporters expressed in the blood-placenta barrier and mammary gland to the drug-transfer into placenta and milk should be considered.

Restoration of FGF receptor type 2 enhances radiosensitivity of hormone-refractory human prostate carcinoma PC-3 cells

BACKGROUND

This study was undertaken to investigate the radiosensitizing effects of fibroblast growth factor receptor 2IIIb (FGFR2IIIb) in androgen-independent human prostate carcinoma PC-3 cells devoid of normally resident epithelial cell FGFR2IIIb.

MATERIALS AND METHODS

A clonal line of PC-3 cells expressing FGFR2IIIb was established by stable transfection. Clonogenic cell survival, apoptosis and cell cycle distribution with and without gamma-irradiation were then compared between FGFR2IIIb-expressing PC-3 cells and control cells mock-transfected with vector alone.

RESULTS

Gamma-irradiation resulted in an increase of clonogenic cell death concurrent with enhanced apoptosis and cell cycle arrest in the G2/M-phase in both transfected and untransfected cells. A quantitative analysis of all three parameters indicated that cells expressing FGFR2IIIb were significantly more sensitive to irradiation than control cells.

CONCLUSION

These results indicate that restoration of FGFR2IIIb to PC-3 cells enhances their sensitivity to irradiation through acceleration of apoptosis and cell cycle arrest.

Inguinal hernia after radical perineal prostatectomy: comparison with the retropubic approach

OBJECTIVES

To clarify the characteristics of inguinal hernia (IH) after radical perineal prostatectomy (RPP) compared with that after radical retropubic prostatectomy (RRP).

METHODS

We retrospectively reviewed 285 and 311 men who underwent RPP and RRP, respectively, for clinically localized prostate cancer between August 2000 and June 2006, using medical records and a telephone survey.

RESULTS

The incidence of postoperative IH after RPP was 1.8% (5 of 285) with a median follow-up time of 43 months; that after RRP was 10.3% (32 of 311) with a median follow-up of 36 months (P <0.0001). The cumulative IH-free rate was significantly higher after RPP than after RRP (P <0.0001, log-rank test). Three of the five RPP patients (60%) developed IH more than 24 months after surgery, whereas 25 of 32 (78%) of the RRP group did so within 24 months (P = 0.0742). The incidence rate of post-RPP IH did not differ between the standard (4 of 194 = 2.1%) and modified (1 of 91 = 1.1%) RPP procedures, where the endopelvic fascia was left intact and opened, respectively (P = 0.5638).

CONCLUSIONS

The incidence of IH after RPP appears to be sporadic and about the same as that (2.0-2.4%) reported previously in men with prostate cancer treated nonsurgically. Although some kinds of procedures during RRP are speculated to affect the internal inguinal ring, prostatectomy with or without opening of the endopelvic fascia seems to be less implicated in the development of IH after RRP because it was not a significant variable in IH development after different techniques had been used in RPP.

Lower urinary tract symptoms after radical perineal prostatectomy

OBJECTIVE

To clarify the impact of radical perineal prostatectomy (RPP) on lower urinary tract symptoms (LUTS) in patients with clinically localized prostate cancer.

METHODS

A total of 117 patients with a median age of 69 years who underwent RPP alone between August 2002 and August 2005 were included in the study. We measured LUTS on the basis of the International Prostate Symptom Score (IPSS) and IPSS quality of life (QOL) questionnaire before, and 3, 6 and 12 months after surgery.

RESULTS

The overall mean total IPSS and IPSS QOL score decreased over time after RPP and was significantly reduced at 12 months after surgery. The decrease of the score was more prominent and rapid in patients with moderate to severe symptoms (IPSS > or = 8), whereas in those with no or only mild symptoms (IPSS < or = 7), the score did not change significantly after RPP. When the patients were divided into groups with baseline scores of 0-1 and 2-5 for each of the seven composites of the IPSS, scores for the 2-5 group improved significantly after RPP in all composites, whereas the 0-1 group had significantly worse scores for voiding frequency and nocturia. No significant change was noted in any of the other five composites.

CONCLUSION

This longitudinal study shows that RPP is significantly beneficial for moderate to severe LUTS, but also has adverse effects on voiding frequency and nocturia in some men with no or mild symptoms. This information is important when counseling patients about treatment options for localized prostate cancer.

Risk Factors for Intravesical Recurrence Following Urothelial Carcinoma of the Upper Urinary Tract: No Relationship to the Mode of Surgery

OBJECTIVE

The aim of this study was to clarify whether intravesical recurrence of upper urinary tract cancer after treatment is related to the mode of surgery or other oncological factors.

METHODS

We evaluated 106 patients (mean age 70.4 years; mean follow-up 24.0 months) who underwent surgery for the upper urinary tract cancer at Hiroshima University and its affiliated hospitals between January 1995 and August 2005. Seventy-nine of the patients underwent retroperitoneoscopy-assisted radical nephroureterectomy (RN) and 27 underwent nephroureterectomy by open surgery (OS). Fifty-two patients had renal pelvic tumors, 48 had ureteral tumors, and six had both renal pelvic and ureteral tumors. Twenty-eight (26%) of the 106 patients had a pre-operative history of bladder cancer. We identified the risk factors predicting intravesical recurrence of upper urinary tract cancer according to the type of previous surgery using the Kaplan-Meier method, log-rank test, and univariate and multivariate analysis using the Cox proportional hazards model.

RESULTS

Thirty-one (29%) of the 106 patients developed bladder tumors post-operatively. The 2-year intravesical recurrence-free rate was 55% in the RN group and 60% in the OS group. There was no significant difference (P = 0.51, log-rank test) in the rate of intravesical recurrence between the two groups. Multivariate analysis identified only a history of pre-operative bladder tumor (HR = 3.25, P = 0.003) as a predictor of post-operative intravesical recurrence.

CONCLUSIONS

Intravesical recurrence after surgery for upper urinary tract cancer is not related to the mode of surgery (i.e. laparoscopy-assisted or open surgery) employed. The only risk factor for intravesical recurrence is a history of bladder cancer.

DNA methylation of the RIZ1 gene is associated with nuclear accumulation of p53 in prostate cancer

The retinoblastoma protein-interacting zinc finger gene, RIZ1, is thought to be a tumor suppressor gene. RIZ1 is inactivated by mutation, deletion and DNA methylation in several human cancers. In the present study, the relationship between DNA methylation of RIZ1 and mutation of p53 was investigated in prostate cancer (PCa). In total, 47 cases of node-negative PCa (stages I-III) were analyzed. DNA methylation of the RIZ1 gene was detected in 20 (42.6%) of the 47 PCa tissues by methylation-specific polymerase chain reaction. DNA methylation of the RIZ1 gene was not associated with clinicopathological features. DNA methylation of RIZ1 tended to be present more frequently in PCa specimens with a high Gleason score (16/30, 53.3%) than in those with a low Gleason score (4/17, 23.5%); however, this tendency was not statistically significant (P = 0.0675). Nuclear accumulation of p53 was observed in four (8.5%) of 47 PCa specimens by immunostaining. All four PCa specimens with nuclear accumulation of p53 were stage III disease and showed DNA methylation of RIZ1. However, of the remaining 43 cancers without nuclear accumulation of p53, DNA methylation of RIZ1 was observed in only 16 (37.2%) specimens (P = 0.0272). Of the three PCa cell lines, only the PC3 cell line showed loss of RIZ1 mRNA due to DNA methylation, and this loss was rectified by treatment with a demethylating agent, 5-Aza-2'-deoxycytidine. These results suggest that transcriptional inactivation of RIZ1 by aberrant DNA methylation may contribute to prostate carcinogenesis. Genetic alterations are likely associated with epigenetic alterations in PCa.

GASDERMIN, suppressed frequently in gastric cancer, is a target of LMO1 in TGF-β-dependent apoptotic signalling

Defining apoptosis-regulatory cascades of the epithelium is important for understanding carcinogenesis, since cancer cells are considered to arise as a result of the collapse of the cascades. We previously reported that a novel gene GASDERMIN (GSDM) is expressed in the stomach but suppressed in gastric cancer cell lines. Furthermore, in this study, we demonstrated that GSDM is expressed in the mucus-secreting pit cells of the gastric epithelium and frequently silenced in primary gastric cancers. We found that GSDM has a highly apoptotic activity and its expression is regulated by a transcription factor LIM domain only 1 (LMO1) through a sequence to which Runt-related transcription factor 3 (RUNX3) binds, in a GSDM promoter region. We observed coexpression of GSDM with LMO1, RUNX3 and type II transforming growth factor-beta receptor (TGF-betaRII) in the pit cells, and found that TGF-beta upregulates the LMO1- and GSDM-expression in the gastric epithelial cell line and induces apoptosis, which was confirmed by the finding that the apoptosis induction is inhibited by suppression of each LMO1-, RUNX3- and GSDM expression, respectively. The present data suggest that TGF-beta, LMO1, possibly RUNX3, and GSDM form a regulatory pathway for directing the pit cells to apoptosis.