Prediction of cell cycle distribution after drug exposure by high content imaging analysis using low-toxic DNA staining dye.

Interference in cell cycle progression has been noted as one of the important properties of anticancer drugs. In this study, we developed the cell cycle prediction model using high-content imaging data of recipient cells after drug exposure and DNA-staining with a low-toxic DNA dye, SiR-DNA. For this purpose, we exploited HeLa and MCF7 cells introduced with a fluorescent ubiquitination-based cell cycle indicator (Fucci). Fucci-expressing cancer cells were subjected to high-content imaging analysis using OperettaCLS after 36-h exposure to anticancer drugs; the nuclei were segmented, and the morphological and intensity properties of each nucleus characterized by SiR-DNA staining were calculated using imaging analysis software, Harmony. For the use of training, we classified cells into each phase of the cell cycle using the Fucci system. Training data (n = 7500) and validation data (n = 2500) were randomly sampled and the binary classification prediction models for G1, early S, and S/G2/M phases of the cell cycle were developed using four supervised machine learning algorithms. We selected random forest as the model with the best performance through 10-fold cross-validation; the accuracy rate was approximately 75%-87%. Regarding feature importance, variables expected to be biologically related to the cell cycle, for example, signal intensity and nuclear size, were highly ranked, suggesting the validity of the model. These results showed that the cell cycle can be predicted in cancer cells by simply exploiting the current prediction model using fluorescent images of DNA-staining dye, and the model could be applied for the use of future ex vivo drug sensitivity diagnosis.

[Questionnaire Survey on the Timing of Comprehensive Genomic Profiling for Advanced Recurrent Colorectal Cancer and Its Impact on Patients].

BACKGROUNDS: Comprehensive genomic profiling(CGP)has been covered by health insurance since June 2019. However, the clinical impact of CGP on patients with metastatic colorectal cancer(mCRC)remains unclear. To date, there are very limited reports regarding patient-oriented outcomes of CGP in mCRC. PATIENTS: A questionnaire was completed by patients with mCRC who had already received their CGP results after April 2021. Eight questions were posed, covering the degree of satisfaction and timing when CGP was conducted. RESULTS: Of the 51 patients with mCRC who had received their CGP test results by August 2021 in our department, 21 patients responded to our questionnaire. In total 66.7% patients with mCRC answered "(very)satisfied"with the CGP testing. 28.6% of the patients already knew about CGP testing before their local doctors informed them. Except for 3 patients who did not answer, 47.6% and 9.5% of patients with mCRC"agreed"and "moderately agreed"with the timing of the CGP test. CONCLUSION: Although most patients with mCRC failed to access promising new treatment via CGP, approximately half of the patients answered that they were satisfied with the CGP testing. Conversely, a few patients already knew about CGP testing before it was proposed by their doctors. Thus, the provision of information at an early stage is necessary.

[Educational Project of Self-Removal of the Intravenous Central Venous Access Port Guided by Patients with Advanced Colorectal Cancer Instructed by a Nurse in the University Hospital].

BACKGROUND: Fluorouracil infusion for 46±5h from the central venous(CV)port is required for mFOLFOX6, FOLFIRI, and FOLFOXIRI in patients with advanced colorectal cancer(CRC), followed by self-removal of the needle by patients. At our hospital, outpatients were instructed for self-removal of the needle, but the results were unsatisfactory. Therefore, instructions for self-removal of the needle from the CV port have been initiated at the patient ward since April 2019, making use of a hospital stay of 3 days. PATIENTS: We retrospectively enrolled patients with chemotherapy-introduced advanced CRC from the CV port who received instructions for self-removal of the needle in the outpatient department and ward between January 2018 and December 2021. RESULTS: Of all patients with advanced CRC, 21 received instructions at the outpatient department(OP)while 67 at patient ward(PW). Incidences of successful self-removal of the needle without the aid of others were similar: 47% in OP and 52% in PW(p=0.80). However, after several additional instructions involving their families, it was higher in PW than in OP(97.0 vs 76.1%, p=0.005). Incidences of successful self-removal of the needle without the aid of others in those aged≥75/<75, and≥65/<65 years were 0%/61.1%, and 35.4%/67.5%, respectively. OP was as a risk factor for failed self-removal of the needle in the logistic regression analysis(odds ratio: 11.19, 95%CI: 1.86- 67.30). CONCLUSION: Repeated instructions involving patients' families during the hospital stay improved the incidence of successful self-removal of the needle. Involvement of patients' families from the beginning may effectively improve self- removal of the needle, particularly in the elderly patients with advanced CRC.

Comprehensive Genomic Profiling Detects Hereditary Cancers and Confers Survival Advantage in Patients With Gynaecological Cancers.

BACKGROUND/AIM: The clinical benefits of comprehensive genomic profiling (CGP) of tumours in patients with gynaecological cancers remain unknown. We investigated the utility of CGP in assessing patient survival and its efficacy in detecting hereditary cancers in gynaecological patients. PATIENTS AND METHODS: We retrospectively analysed the medical records of 104 gynaecological patients who underwent CGP between August 2018 and December 2022. The detection of actionable and accessible genomic alterations and administration of targeted therapy, as recommended by the molecular tumour board (MTB), were assessed. The overall survival (after second-line treatment in cervical and endometrial carcinomas and after platinum-resistant recurrence in ovarian carcinoma) was compared between patients with or without administration of MTB-recommended genotype-matched therapy. Germline findings were assessed using a variant allele frequency-tumour content graph. RESULTS: Among 104 patients, actionable and accessible genomic alterations were observed in 53 patients. Matched therapy was applied in 21 patients, comprising administration of repurposing itraconazole (n=7), immune checkpoint inhibitors (n=7), poly (ADP-ribose) polymerase inhibitors (n=5), and others (n=2). The median overall survival of patients receiving and not receiving matched therapy were 19.3 months and 11.2 months, respectively (p=0.036, hazard ratio=0.48). Among 12 patients with hereditary cancers, 11 patients were previously undiagnosed. Seven patients had hereditary breast and ovarian cancer, and five had other cancer. CONCLUSION: The implementation of CGP testing prolonged overall survival in gynaecological cancer as well as provided an opportunity for genetic counselling for newly-diagnosed patients with hereditary cancers and their families.

[Challenge of Skin Treatment Led by Nurses and Pharmacists for Advanced Colorectal Cancer Patients Treated with Anti-EGFR Antibodies].

Preemptive skin treatment led by nurses and pharmacists was started for patients with metastatic colorectal cancer (mCRC)who received anti-EGFR antibody treatment. Incidence of skin-related toxicities, amount of topical moisturizers used, and administered cycles of anti-EGFR antibody were retrospectively compared between a preemptive skin treatment group and a control group. Thirty-four mCRC patients before the introduction of preemptive skin treatment led by nurses and 23 mCRC patients treated with preemptive skin treatment led by nurses were evaluated. The incidence of 6- and 12- week Grade 2 or higher skin-related toxicity was 23.5% in the control group and 8.7% in the preemptive group(p=0.18), and 67.7% in the control group and 30.4% in the preemptive group(p=0.0076), respectively. Mean amounts of moisturizer used were both lower in the control group than in the preemptive group at both 6 weeks and 7-12 weeks(6 weeks; 275 g vs 550 g, p=0.036, 7-12 weeks; 575 g vs 1,175 g, p=0.013). However, the amount of topical steroid used was similar in both groups. Preemptive moisturizer skin treatment led by nurses and pharmacists may decrease the incidence of skin- related toxicity.

[Cross-Functional Project of Using Information-Sharing Tool for Metastatic Colorectal Cancer Patients in University Hospital].

Treatment for late-stage cancer patients should be discussed depending on the patients' will, however it is not sometimes fully discussed in our daily practice. Based on this background, the information-sharing tool for metastatic colorectal cancer patients, who are refractory to first-line and second-line chemotherapy and/or who are given a year to live, has been introduced in our university hospital since November 2019. To evaluate the utility of this tool, the influence of the tools on the outcome of the patients was evaluated. Regarding the comparison between the patients before and after the introduction of the information-sharing tool, the period between the day of the consent to the DNAR between the day of the death is longer in the patients after the introduction than those before the introduction(median 43 vs 6 days, p=0.025). The introduction of the information-sharing tool can provide the metastatic colorectal cancer patients with more opportunities to discuss how to spend the rest of their lives and with longer time at the place where they want to stay.

Mechanistic study of PpIX accumulation using the JFCR39 cell panel revealed a role for dynamin 2-mediated exocytosis.

5-aminolevulinic acid (5-ALA) has recently been employed for photodynamic diagnosis (ALA-PDD) and photodynamic therapy (ALA-PDT) of various types of cancer because hyperproliferating tumor cells do not utilize oxidative phosphorylation and do not efficiently produce heme; instead, they accumulate protoporphyrin IX (PpIX), which is a precursor of heme that is activated by violet light irradiation that results in the production of red fluorescence and singlet oxygen. The efficiencies of ALA-PDD and ALA-PDT depend on the efficient cellular uptake of 5-ALA and the inefficient excretion of PpIX. We employed the JFCR39 cell panel to determine whether tumor cells originating from different tissues can produce and accumulate PpIX. We also investigated cellular factors/molecules involved in PpIX excretion by tumor cells with the JFCR39 cell panel. Unexpectedly, the expression levels of ABCG2, which has been considered to play a major role in PpIX extracellular transport, did not show a strong correlation with PpIX excretion levels in the JFCR39 cell panel, although an ABCG2 inhibitor significantly increased intracellular PpIX accumulation in several tumor cell lines. In contrast, the expression levels of dynamin 2, which is a cell membrane-associated molecule involved in exocytosis, were correlated with the PpIX excretion levels. Moreover, inhibitors of dynamin significantly suppressed PpIX excretion and increased the intracellular levels of PpIX. This is the first report demonstrating the causal relationship between dynamin 2 expression and PpIX excretion in tumor cells.

Antitumor profile of the PI3K inhibitor ZSTK474 in human sarcoma cell lines.

Treatment of patients with advanced sarcoma remains challenging due to lack of effective medicine, with the development of novel drugs being of keen interest. A pan-PI3K inhibitor, ZSTK474, has been evaluated in clinical trials against a range of advanced solid tumors, with clinical benefit shown in sarcoma patients. In the present study, we developed a panel of 14 human sarcoma cell lines and investigated the antitumor effect of 24 anticancer agents including ZSTK474, other PI3K inhibitors, and those clinically used for sarcoma treatment. ZSTK474 exhibited a similar antiproliferative profile to other PI3K inhibitors but was clearly different from the other drugs examined. Indeed, ZSTK474 inhibited PI3K-downstream pathways, in parallel to growth inhibition, in all cell lines examined, showing proof-of-concept of PI3K inhibition. In addition, ZSTK474 induced apoptosis selectively in Ewing's sarcoma (RD-ES and A673), alveolar rhabdomyosarcoma (SJCRH30) and synovial sarcoma (SYO-1, Aska-SS and Yamato-SS) cell lines, all of which harbor chromosomal translocation and resulting oncogenic fusion genes, EWSR1-FLI1, PAX3-FOXO1 and SS18-SSX, respectively. Finally, animal experiments confirmed the antitumor activity of ZSTK474 in vivo, with superior efficacy observed in translocation-positive cells. These results suggest that ZSTK474 could be a promising drug candidate for treating sarcomas, especially those harboring chromosomal translocation.

Infants' emotional states influence maternal behaviors during holding.

Previous studies have mainly examined how maternal behaviors influence infants during holding. However it is unclear how infants influence maternal holding. This current study investigated how infants' emotional states influence maternal holding behaviors, and whether maternal holding behaviors are also influenced by the mothers' parenting stress. We manipulated infants' emotional states and videotaped mothers' holding behaviors. The mothers also completed a questionnaire about their parental stress. Results showed that mothers varied their holding behaviors depending on their infants' emotional states. When infants were comfortable, mothers rocked them horizontally and quietly. When infants were uncomfortable, mothers rocked them vertically at a high frequency. Furthermore, some types of parenting stress were related to several types of maternal behaviors in the context of holding. These findings suggest that maternal holding behaviors are influenced by both the infants' emotional states and the mothers' parenting stress.

Basal expression of insulin-like growth factor 1 receptor determines intrinsic resistance of cancer cells to a phosphatidylinositol 3-kinase inhibitor ZSTK474.

Drug resistance often critically limits the efficacy of molecular targeted drugs. Although pharmacological inhibition of phosphatidylinositol 3-kinase (PI3K) is an attractive therapeutic strategy for cancer therapy, molecular determinants for efficacy of PI3K inhibitors (PI3Kis) remain unclear. We previously identified that overexpression of insulin-like growth factor 1 receptor (IGF1R) contributed to the development of drug resistance after long-term exposure to PI3Kis. In this study, we examined the involvement of basal IGF1R expression in intrinsic resistance of drug-naïve cancer cells to PI3Kis and whether inhibition of IGF1R overcomes the resistance. We found that cancer cells highly expressing IGF1R showed resistance to dephosphorylation of Akt and subsequent antitumor effect by ZSTK474 treatment. Knockdown of IGF1R by siRNAs facilitated the dephosphorylation and enhanced the drug efficacy. These cells expressed tyrosine-phosphorylated insulin receptor substrate 1 at high levels, which was dependent on basal IGF1R expression. In these cells, the efficacy of ZSTK474 in vitro and in vivo was improved by its combination with the IGF1R inhibitor OSI-906. Finally, we found a significant correlation between the basal expression level of IGF1R and the inefficacy of ZSTK474 in an in vivo human cancer panel, as well as in vitro. These results suggest that basal IGF1R expression affects intrinsic resistance of cancer cells to ZSTK474, and IGF1R is a promising target to improve the therapeutic efficacy. The current results provide evidence of combination therapy of PI3Kis with IGF1R inhibitors for treating IGF1R-positive human cancers.

Bisabololoxide A, one of the constituents in German chamomile extract, attenuates cell death induced by calcium overload.

Bisabololoxide A (BSBO), main constituents in German chamomile extract, is responsible for antipruritic effect. In previous study, the incubation with 30-100 µM BSBO for 24 h exerted cytotoxic and proapoptotic effects on rat thymocytes. To further characterize BSBO cytotoxicity, the effect on the cells suffering from calcium overload by calcium ionophore A23187 was examined. A23187 induced Ca(2+) -dependent cell death. Contrary to our expectation, 1-10 µM BSBO inhibited A23187-induced increase in cell lethality of rat thymocytes. BSBO attenuated A23187-induced increases in populations of shrunken living cells, phosphatidylserine-exposed living cells, and dead cells, without affecting the increase in intracellular Ca(2+) concentration and the Ca(2+) -dependent hyperpolarization. The effect of BSBO on A23187-treated cells may be unique because the activation of Ca(2+) -dependent K(+) channels is required for cell shrinkage, externalization of phosphatidylserine, and cell death in some cells. The cell death induced by A23187 was not inhibited by Z-VAD-FMK, a pan-inhibitor of caspases. Thus, the cell death may be a necrosis with some features observed during an early stage of apoptosis. These results suggest that BSBO at low micromolar concentrations is cytoprotective against calcium overload.

Nanomolar concentration of triclocarban increases the vulnerability of rat thymocytes to oxidative stress.

It was recently reported that triclocarban was absorbed significantly from soap used during showering in human subjects and that its C(max) in their whole blood ranged from 23 nM to 530 nM. We revealed that a nanomolar concentration (300 nM) of triclocarban potentiated the cytotoxicity of 300 µM H(2)O(2) in rat thymocytes by using cytometric techniques with appropriate fluorescent probes. Although 300 nM triclocarban did not itself increase the population of dead cells (cell lethality), it facilitated the process of cell death induced by H(2)O(2), resulting in a further increase in the population of dead cells. Nanomolar concentrations (300 nM or higher) of triclocarban significantly decreased the cellular content of nonprotein thiol (glutathione), which has a protective role against oxidative stress. Triclocarban at 300 nM or higher increased the cell vulnerability to oxidative stress. The results may suggest that nanomolar concentration (300 nM or higher) of triclocarban affects some cellular functions although there is no evidence for adverse effects of triclocarban in humans at present.

Establishment of phosphatidylinositol 3-kinase inhibitor-resistant cancer cell lines and therapeutic strategies for overcoming the resistance.

Acquired resistance is a major obstacle for conventional cancer chemotherapy, and also for some of the targeted therapies approved to date. Long-term treatment using protein tyrosine kinase inhibitors (TKIs), such as gefitinib and imatinib, gives rise to resistant cancer cells carrying a drug-resistant gatekeeper mutation in the kinase domain of the respective target genes, EGFR and BCR-ABL. As for the phosphatidylinositol 3-kinase inhibitors (PI3Kis), little is known about their acquired resistance, although some are undergoing clinical trials. To address this issue, we exposed 11 human cancer cell lines to ZSTK474, a PI3Ki we developed previously, for a period of more than 1 year in vitro. Consequently, we established ZSTK474-resistant cells from four of the 11 cancer cell lines tested. The acquired resistance was not only to ZSTK474 but also to other PI3Kis. None of the PI3Ki-resistant cells, however, contained any mutation in the kinase domain of the PIK3CA gene. Instead, we found that insulin-like growth factor 1 receptor (IGF1R) was overexpressed in all four resistant cells. Interestingly, targeted knockdown of IGF1R expression using specific siRNAs or inhibition of IGF1R using IGF1R-TKIs reversed the acquired PI3Ki resistance. These results suggest that long-term treatment with PI3Kis may cause acquired resistance, and targeting IGF1R is a promising strategy to overcome the resistance.

Bisabololoxide A, one of the main constituents in German chamomile extract, induces apoptosis in rat thymocytes.

German chamomile (Matricaria recutita L.), one of the popular ingredients in herbal teas, has been traditionally used for medicinal purposes. Bisabololoxide A (BSBO) is one of the main constituents in this herb. BSBO is supposed to be principle in some bioactivities of German chamomile such as anti-inflammatory, gastrointestinal, and antipruritic actions. Although the use of German chamomile has spread, the information related to toxicity of BSBO is very limited. In present study, the cytotoxic effect of micromolar BSBO was cytometrically examined on rat thymocytes by using appropriate fluorescent dyes. When the cells were incubated with BSBO for 24 h, BSBO at concentrations of 30 microM or more significantly increased populations of dead cells, shrunken cells, and cells with phosphatidylserine exposed on membrane surface. Both cell shrinkage and externalization of membrane phosphatidylserine are general features in an early stage of apoptosis. In addition, BSBO significantly increased population of cells containing hypodiploid DNA, and the increase was completely attenuated by Z-VAD-FMK, a pan-inhibitor for caspases, indicating an involvement of caspase activation. Thus, it is likely that the type of cell death induced by BSBO is apoptosis. The significant changes in cellular parameters of rat thymocytes by BSBO were not observed when the concentration was 10 microM or less. Furthermore, the short incubation (3 h) of cells even with 30-100 microM BSBO did not significantly affect the cells. Therefore, it may be suggested that BSBO is practically safe when German chamomile is conventionally used.

Micromolar Zn(2+) potentiates the cytotoxic action of submicromolar econazole in rat thymocytes: possible disturbance of intracellular Ca(2+) and Zn(2+) homeostasis.

Econazole, one of imidazole antifungals, has been reported to exhibit an inhibitory action on Mycobacterium tuberculosis and its multidrug-resistant strains under in vitro and ex vivo conditions. There is a chemotherapeutic potential of econazole against tuberculosis. We have revealed that Zn(2+) at micromolar concentrations potentiates the cytotoxicity of imidazole antifungals by increasing membrane Zn(2+) permeability. It is reminiscent of a possibility that econazole exhibits harmful action on human in the presence of Zn(2+) at a physiological range when the agent is systemically administered. Because it is necessary to characterize the cytotoxic action of econazole in the presence of Zn(2+), we have cytometrically examined the effects of econazole, ZnCl(2), and their combination on rat thymocytes. ZnCl(2) at concentrations ranging from 1 microM to 30 microM significantly increased the lethality induced by 10 microM econazole in a concentration-dependent manner. Econazole at a sublethal concentration of 1 microM significantly augmented the intensity of side scatter in the presence of micromolar ZnCl(2), suggesting the change in an intracellular circumstance by the combination of econazole and ZnCl(2). Econazole at 0.3 microM or more in the presence of ZnCl(2) increased the intensity of Fluo-3 fluorescence, an indicator for intracellular Ca(2+). Furthermore, the intensity of FluoZin-3 fluorescence, an indicator for intracellular Zn(2+), was also augmented by econazole at 0.1 microM or more in the presence of ZnCl(2). Results suggest that the combination of submicromolar econazole with micromolar ZnCl(2) may increase the intracellular concentration of Ca(2+) and Zn(2+), leading to disturbance of intracellular Ca(2+) and Zn(2+) homeostasis that triggers cytotoxic action.

Increase in intracellular Zn2+ concentration by thimerosal in rat thymocytes: intracellular Zn2+ release induced by oxidative stress.

Thimerosal (TMR), an ethylmercury-containing preservative in pharmaceutical products, was recently reported to increase intracellular Zn(2+) concentration. Therefore, some health concerns about the toxicity of TMR remain because of physiological and pathological roles of Zn(2+). To reveal the property of TMR-induced increase in intracellular Zn(2+) concentration, the effect of TMR on FluoZin-3 fluorescence, an indicator of intracellular Zn(2+), of rat thymocytes was examined. TMR at concentrations ranging from 0.3 microM to 10 microM increased the intensity of FluoZin-3 fluorescence in a concentration-dependent manner under external Ca(2+)- and Zn(2+)-free condition. The threshold concentration was 0.3-1 microM. The increase in the intensity was significant when TMR concentration was 1 microM or more. N,N,N',N'-Tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a chelator for intracellular Zn(2+), completely attenuated the TMR-induced augmentation of FluoZin-3 fluorescence. Hydrogen peroxide (H(2)O(2)) and N-ethylmaleimide, reducing cellular thiol content, significantly increased FluoZin-3 fluorescence intensity and decreased 5-chloromethylfluorescein (5-CMF) fluorescence intensity, an indicator for cellular thiol. The correlation coefficient between TMR-induced augmentation of FluoZin-3 fluorescence and attenuation of 5-CMF fluorescence was -0.882. TMR also attenuated the 5-CMF fluorescence in the presence of TPEN. Simultaneous application of H(2)O(2) and TMR synergistically augmented the FluoZin-3 fluorescence. It is suggested that TMR increases intracellular Zn(2+) concentration via decreasing cellular thiol content.

Cytometric analysis of cytotoxicity of polyphenols and related phenolics to rat thymocytes: potent cytotoxicity of resveratrol to normal cells.

The chemopreventive and chemotherapeutic actions of polyphenols and related phenolics have received considerable attention since these compounds induce apoptosis in several types of cancer cells in vitro. A plausible criterion for the use of such compounds is that they should not exert any toxic effect on normal cells. However, information about the toxicity of polyphenols and related phenolics to normal cells is limited. In this study, the effects of polyphenols and related phenolics on rat thymocytes were examined by flow cytometric analysis with appropriate fluorescent probes. The compounds examined in this study were caffeic acid, rosmarinic acid, chlorogenic acid, (+)-catechin, 6-gingerol, sesamol, resveratrol, and eugenol. Of these, resveratrol was the most cytotoxic on rat thymocytes incubated for 24 hrs with 100 microM of this compound. Resveratrol at a concentration of 10 microM or more (up to 100 microM) led to a significant dose-dependent increase in the population of dead cells, shrunken living cells, annexin V-positive cells and cells with hypodiploidal DNA. In the presence of benzyloxycarbonyl-Val-Ala-Asp (OMe) fluoromethylketone (Z-VAD-FMK), a pan-inhibitor of caspases, the resveratrol-induced increase in the population of cells with hypodiploidal DNA was partially inhibited. Overall, it is suggested that resveratrol at a concentration of 10 microM or more induces apoptosis in normal cells as well as cancer cells (previously reported elsewhere). Thus, at concentrations that are suitable for chemopreventive and chemotherapeutic actions, resveratrol may exert a cytotoxic effect on normal cells.

[Epidemiology of sexually transmitted diseases in Japan--its international characteristics].

Japan has witnessed the rise of STDs, and the increase in the number of HIV cases infected through sexual contact in the last decade. Background of these trends will be the exceptionally high prevalence of paid sex in Japan among developed countries and the diversified unprotected sexual behaviors that have prevailed among general population since 1990s. STDs are also increasing and HIV infection through sexual contact has resumed to increase among other developed countries in the same period of time. Coordinated research among developed countries is becoming increasingly important to clarify the specific and general causes of such phenomena and thus to explore the possibility of coordinated responses toward these global challenges.

Zn(2+), derived from cell preparation, partly attenuates Ca(2+)-dependent cell death induced by A23187, calcium ionophore, in rat thymocytes.

A23187, a calcium ionophore, is used to induce Ca(2+)-dependent cell death by increasing intracellular Ca(2+) concentration ([Ca(2+)](i)) under in vitro condition. Since this ionophore also increases membrane permeability of metal divalent cations such as Zn(2+) and Fe(2+) rather than Ca(2+), trace metal cations in cell suspension may affect Ca(2+)-dependent cell death induced by A23187. Therefore, the effects of chelators for divalent metal cations, EDTA and TPEN, on the A23187-induced cytotoxicity were cytometrically examined in rat thymocytes. The cytotoxicity of A23187 was attenuated by 1mM EDTA while it was augmented by 50 microM EDTA and 10 microM TPEN. These changes were statistically significant. The A23187-induced increase in Fluo-3 fluorescence intensity, a parameter for [Ca(2+)](i), was significantly reduced by 1mM EDTA while it was not the case for 50 microM EDTA and 10 microM TPEN. The intensity of FluoZin-3 fluorescence, a parameter for [Zn(2+)](i), increased by A23187 was respectively reduced by 50 microM EDTA and 10 microM TPEN. It is suggested that the attenuation of A23187-induced cytotoxicity by 1mM EDTA is due to the chelation of extracellular Ca(2+) and Zn(2+) while the augmentation by 50 microM ETDA or 10 microM TPEN is due to the chelation of extracellular Zn(2+). The Tyrode's solution without thymocytes contained 32.4 nM of zinc while it was 216.9 nM in the cell suspension. In conclusion, trace Zn(2+), derived from cell preparation, partly attenuates the Ca(2+)-dependent cell death induced by A23187.

Demographic and behavioral characteristics of male sexually transmitted disease patients in Japan: a nationwide case-control study.

BACKGROUND: Sexually transmitted infections (STIs) increased rapidly in Japan during the 1990s. METHODS: To determine the epidemiologic characteristics of STI patients, male cases (n = 765) from 21 clinics across Japan and controls from the general population (n = 1,167), both aged 18 to 59 years, were compared using two datasets of nationwide sexual behavior surveys conducted in 1999. RESULTS: Male STI patients were more likely to be <40 years of age (OR = 3.94, 95% CI: 2.17, 7.15), unmarried (OR = 2.65, 95% CI: 1.80, 3.91), and at least college/university educated (OR = 2.03, 95% CI: 1.45, 2.83). They were also more likely to have had multiple partnerships in the previous year (OR = 3.33, 95% CI: 2.20, 5.05 for 2-3 partners, OR = 6.29, 95% CI: 3.81, 10.37 for >or=4 partners), unprotected vaginal sex with regular partners (OR = 2.70, 95% CI: 1.75, 4.17), unprotected vaginal and/or oral sex with casual partners (OR = 2.14, 95% CI: 1.40, 3.26), and unprotected vaginal (OR = 2.64, 95% CI: 1.46, 4.80) and oral sex with paid partners (OR = 4.72, 95% CI: 3.04, 7.32) in the previous year. CONCLUSIONS: These results suggest that male STI patients in Japan are highly educated and have a diverse occupational background, and that STI risks exist universally for various types of sex and sexual partnerships.