Acid-Sensitive Outwardly Rectifying Cl- Current in OV2944 Mouse Ovarian Cancer Cells

BACKGROUND/AIMS

Extracellular acidic conditions impair cellular activities; however, some cancer cells drive cellular signaling to adapt to the acidic environment. It remains unclear how ovarian cancer cells sense changes in extracellular pH. This study was aimed at characterizing acid-inducible currents in an ovarian cancer cell line and evaluating the involvement of these currents in cell viability.

METHODS

The biophysical and pharmacological properties of membrane currents in OV2944, a mouse ovarian cancer cell line, were studied using the whole-cell configuration of the patch-clamp technique. Viability of this cell type in acidic medium was evaluated using the MTT assay.

RESULTS

OV2944 had significant acid-sensitive outwardly rectifying (ASOR) Cl- currents at a pH50 of 5.3. The ASOR current was blocked by pregnenolone sulfate (PS), a steroid ion channel modulator that blocks the ASOR channel as one of its targets. The viability of the cells was reduced after exposure to an acidic medium (pH 5.3) but was slightly restored upon PS administration.

CONCLUSION

These results offer first evidence for the presence of ASOR Cl- channel in ovarian cancer cells and indicate its involvement in cell viability under acidic environment.

Selective epigenetic alterations in RNF43 in pancreatic exocrine cells from high-fat-diet-induced obese mice; implications for pancreatic cancer

OBJECTIVE

Pancreatic cancer (PC) originates and progresses with genetic mutations in various oncogenes and suppressor genes, notably KRAS, CDKN2A, TP53, and SMAD4, prevalent across diverse PC cells. In addition to genetic mutations/deletions, persistent exposure to high-risk factors, including obesity, induces whole-genome scale epigenetic alterations contributing to malignancy. However, the impact of obesity on DNA methylation in the presymptomatic stage, particularly in genes prone to PC mutation, remains uncharacterized.

RESULTS

We analyzed the methylation levels of 197 loci in six genes (KRAS, CDKN2A, TP53, SMAD4, GNAS and RNF43) using Illumina Mouse Methylation BeadChip array (280 K) data from pancreatic exocrine cells obtained from high-fat-diet (HFD) induced obese mice. Results revealed no significant differences in methylation levels in loci between HFD- and normal-fat-diet (NFD)-fed mice, except for RNF43, a negative regulator of Wnt signaling, which showed hypermethylation in three loci. These findings indicate that, in mouse pancreatic exocrine cells, high-fat dietary obesity induced aberrant DNA methylation in RNF43 but not in other frequently mutated PC-related genes.

Does central venous stenosis affects the brachial artery flow volume and peripheral vascular resistive index in patients on maintenance hemodialysis? A retrospective study

BACKGROUND

A well-functioning vascular access (VA) is crucial for the patients on maintenance hemodialysis (HD). Central venous stenosis (CVS) is a common, yet, overlooked complication of VA as its diagnosis is challenging. Moreover, its effect on the flow volume (FV) and the peripheral resistive index (RI) was not well discussed before. Despite the availability of doppler ultrasound (DUS) in most centers, direct visualization of central veins using DUS is quite difficult.

METHODS

This is a retrospective single-center self-controlled cohort study that was conducted in a specialized vascular access management tertiary center in Japan and included all patients with CVS who underwent percutaneous transluminal angiography (PTA) with or without vascular stenting in the period from January 2014 to September 2022. The patients were divided according to their VA type into arteriovenous fistula (AVF), and arteriovenous graft (AVG) groups, then subdivided, according to the type of stenosis, into two subgroups: CVS, and mixed central and peripheral venous stenosis (MVS) groups. The FV and RI of the feeding artery were compared in the same procedure before and after PTA to assess the impact of the procedure itself.

RESULTS

Data of 485 percutaneous transluminal angiography procedures (PTA), performed in 95 patients during the period from January 2014 to September 2022, were collected. FV and RI were significantly affected in the patients with MVS than patients with CVS. After PTA, both FV and RI were significantly improved. The improvement rate of FV and RI after PTA were significantly higher in patients with MVS than patients with CVS. However, it was difficult to determine the cut-off value to diagnose or to assess the improvement of CVS.

CONCLUSION

Our findings suggest that FV and RI measurement by DUS are good tools, along with the clinical findings for assessment of CVS in certain situations.

Dicalcin suppresses invasion and metastasis of mammalian ovarian cancer cells by regulating the ganglioside-Erk1/2 axis

Metastasis, a multistep process including cancer cell migration and invasion, is the major cause of mortality in patients with cancer. Here, we investigated the effect of dicalcin, a Ca2+-binding protein, on the invasion and metastasis of ovarian cancer (OC) cells. Extracellularly administered dicalcin bound to the membrane of OV2944 cells, mouse OC cells, and suppressed their migration in vitro; however, cell viability or proliferation were unaffected. Repeated intraperitoneal injection of a partial peptide of dicalcin (P6) prolonged the survival, and reduced the number of microcolonies in the livers of cancer-bearing mice. P6 bound to the ganglioside GM1b in a solid-phase assay; treatment with P6 inhibited the constitutive activation of Erk1/2 in OC cells, whereas excess administration of GM1b augmented Erk activity and cancer cell migration in vitro. Thus, dicalcin, a novel suppressor of invasion and metastasis of OC cells, acts via the GM1b-Erk1/2 axis to regulate their migration.

Salivary cortisol as a marker for assessing the problem-focused coping style of stressed students during the first year of university: An experimental study

Background and Aims

First-year students encounter substantial stress when they enter university. Their mental health often depends upon how well they cope with the stress of university life. Salivary components are well known to reflect the stress status of the students; however, the relationship between salivary components and coping styles remains unknown.

Methods

In this study, 54 healthy first-year students voluntarily completed a questionnaire that addressed three different coping styles: problem-focused, emotion-focused, and escape-focused. We simultaneously collected salivary samples from students in the classroom and measured concentrations of salivary cortisol and α-amylase by enzyme-linked immunosorbent assays over 4 months.

Results

We examined the relationship between coping style and salivary cortisol concentrations and found that the mean salivary cortisol concentrations were significantly lower in students who had a higher Likert-type score for the problem-focused coping style than in students who had a lower score. The difference in the mean cortisol concentrations between the two groups increased over time. However, we observed no apparent correlation between α-amylase concentrations and Likert scores of the three coping styles.

Conclusion

These results suggest that salivary cortisol concentrations might reflect the stress-coping status, particularly involving the problem-focused coping style.

Facilitatory Effect of Extending the Course Duration on Dissemination of Educational Content

The physiological practice course at Saitama Medical University provides students with the opportunity to learn physiological principles through wet labs and discussions. To develop a more effective method for maximizing learning outcomes, we extended the course's schedule from one day (1d) to two days (2d) per theme, evaluated self-administered questionnaires between two different years (pre and post-change), and examined whether the increased course length affected learning outcomes. Within the 2018 curriculum year, every theme of the course was completed in a day, including experiments in the wet lab and discussions. In 2019, each theme was assessed for two days. The second-year undergraduate medical students anonymously submitted the self-assessment questionnaire that addressed several aspects, such as understanding of the theme, through a 5-point Likert scale. The average Likert scores varied from 4 to 4.5 point for all questions, and significant differences were not found between the 1d and 2d courses. However, the ratio of students with the highest points increased for one question of the 2d course: 43.6% (1d) to 53.4% (2d) for understanding. Further, the standard deviation (SD) values decreased in the 2d course for every question: 0.29 (1d) to 0.15 (2d) for interest, 0.33 (1d) to 0.19 (2d) for understanding, 0.30 (d) to 0.17 (d) for communication, 0.34 (1d) to 0.19 (2d) for general evaluation. This reduction in the SD values indicated that the educational content was imparted more efficiently to students in the 2d course. Thus, we concluded that extending the course time facilitated dissemination of educational content for every theme.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40670-022-01563-4.

Dicalcin suppresses in vitro trophoblast attachment in human cell lines

Implantation is a highly organized process that involves an interaction between a competent blastocyst and a receptive uterus. Despite significant research efforts, the molecular mechanisms governing this complex process remain elusive. Here, we investigated the effect of dicalcin, an S100-like Ca²⁺-binding protein, on the attachment of choriocarcinoma cells (BeWo cells) onto a monolayer of endometrial carcinoma cells (Ishikawa cells). Extracellularly administered dicalcin bound to both BeWo and Ishikawa cells. Pretreatment of BeWo spheroids with dicalcin reduced the attachment ratio of the spheroids onto the monolayer, whereas that of Ishikawa cells showed no apparent change. We identified the partial amino acid sequence of human dicalcin that exhibited maximum suppression for BeWo spheroid attachment. Transmission electron microscopy analysis revealed that the dicalcin-derived peptide caused a dilation of the intercellular junction between BeWo and ISK cells. Peptide treatment of BeWo spheroids downregulated the expression of integrinαvβ3 in BeWo cells, and induced alterations in their phalloidin-staining pattern, as measured by the length of each F-actin fiber and the thickness of the cortical stress fiber. Thus, dicalcin affects reorganization of the intracellular actin meshwork and subsequently the intensity of attachment, functioning as a novel suppressor of implantation.

GABAergic and glycinergic systems regulate ON-OFF electroretinogram by cooperatively modulating cone pathways in the amphibian retina

The network mechanisms underlying how inhibitory circuits regulate ON- and OFF-responses (the b- and d-waves) in the electroretinogram (ERG) remain unclear. The purpose of this study was to investigate the contribution of inhibitory circuits to the emergence of the b- and d-waves in the full-field ERG in the newt retina. To this end, we investigated the effects of several synaptic transmission blockers on the amplitudes of the b- and d-waves in the ERG obtained from newt eyecup preparations. Our results demonstrated that (a) L-APB blocked the b-wave, indicating that the b-wave arises from the activity of ON-bipolar cells (BCs) expressing type six metabotropic glutamate receptors; (b) the combined administration of UBP310/GYKI 53655 blocked the d-wave, indicating that the d-wave arises from the activity of OFF-BCs expressing kainate-/AMPA-receptors; (c) SR 95531 augmented both the b- and the d-wave, indicating that GABAergic lateral inhibitory circuits inhibit both ON- and OFF-BC pathways; (d) the administration of strychnine in the presence of SR 95531 attenuated the d-wave, and this attenuation was prevented by blocking ON-pathways with L-APB, which indicated that the glycinergic inhibition of OFF-BC pathway is downstream of the GABAergic inhibition of the ON-system; and (e) the glycinergic inhibition from the ON- to the OFF-system widens the response range of OFF-BC pathways, specifically in the absence of GABAergic lateral inhibition. Based on these results, we proposed a circuitry mechanism for the regulation of the d-wave and offered a tentative explanation of the circuitry mechanisms underlying ERG formation.

Structural and rheological properties conferring fertilization competence to Xenopus egg-coating envelope

The extracellular egg-coating envelope that comprises a meshwork of filaments polymerized by glycoproteins plays a pivotal role in species-selective sperm recognition and subsequent fertilization; however, the structural and rheological properties conferring fertilization competence to the egg-coating envelope remain poorly unveiled. Here we show several nanoscale-structural and viscoelastic properties of the egg-coat using the transmission electron microscopy and the quartz crystal microbalance experiments, following clamp of the egg-coat at either fertilization-competent or -incompetent statuses by short-term pretreatment with synthetic peptides. Individual filament of approximately 4.8 nm diameter crossed one another, forming several types of intersections. Higher competence-inducing treatment changed the proportion of V-, Y-, and T-type intersections, and induced more randomly deflected angles at intersections. Incompetence-inducing treatment increased the median of a Gaussian distribution of filament lengths that had a peak of 10–20 nm under control conditions; furthermore, this treatment created bumps in the 30–40 and 50–60 nm windows. Quartz crystal microbalance study revealed that viscoelasticity of the competent VE suspension was lower than that of incompetent VE, indicating that viscoelastic property required for successful fertilization resides within a specific range. These findings indicated that the architecture of the egg-coat is capable of rapid and dynamic remodeling, which determines fertilization efficiency.

Dicalcin, a zona pellucida protein that regulates fertilization competence of the egg coat in Xenopus laevis

Fertilization is a highly coordinated process whereby sperm interact with the egg-coating envelope (called the zona pellucida, ZP) in a taxon-restricted manner, Fertilization triggers the resumption of the cell cycle of the egg, ultimately leading to generation of a new organism that contains hereditary information of the parents. The complete sperm-ZP interaction comprises sperm recognition of the ZP, the acrosome reaction, penetration of the ZP, and fusion with the egg. Recent evidence suggests that these processes involve oligosaccharides associated with a ZP constituent (termed ZP protein), the polypeptide backbone of a ZP protein, and/or the proper three-dimensional filamentous structure of the ZP. However, a detailed description of the molecular mechanisms involved in sperm-ZP interaction remains elusive. Recently, I found that dicalcin, a novel ZP protein-associated protein, suppresses fertilization through its association with gp41, the frog counterpart of the mammalian ZPC protein. This review focuses on molecular aspects of sperm-ZP interaction and describes the fertilization-suppressive function of dicalcin and associated molecular mechanisms. The amount of dicalcin in the ZP significantly correlates with alteration of the lectin-staining pattern within the ZP and the orientation pattern of ZP filaments, which may assist in elucidating the complex molecular mechanisms that underlie sperm-ZP interaction.

Synergic carcinostatic effects of ascorbic acid and hyperthermia on Ehrlich ascites tumor cell

AIM

In this study, we evaluated the carcinostatic effects of combined ascorbic acid (AsA) and a capacitive-resistive electric transfer (CRet) hyperthermic apparatus-induced hyperthermic treatment on Ehrlich ascites tumor (EAT) cells.

MATERIALS AND METHODS

EAT cells were exposed to various AsA (0-10 mM) concentrations for 1 h; they subsequently underwent CRet treatment for 15 min at 42 °C. Cell viability was assessed by the WST-8 assay 24 h after the combined treatment. Reactive oxygen species involvement was evaluated using catalase and tempol; caspase-3/7 activation was determined by their fluorescent substrates; cell proliferation were estimated by time-lapse observation. The effect on the cell cycle was analyzed by flow cytometry.

RESULTS

Combined AsA and CRet treatment synergistically suppressed cell viability compared with either treatment alone, and these synergistically carcinostatic effects were evident even at noncytotoxic concentrations of AsA alone (≤ 2 mM). The carcinostatic effects of combined AsA and CRet treatment were attenuated in a dose-dependent manner by catalase addition, but not by the superoxide anion radical scavenger tempol. Time-lapse observation revealed that combined AsA and CRet treatment activated caspase-3/7 at 10-24 h after treatment, accompanied by significant cell growth suppression. Cell cycle analysis revealed that the rate of sub-G1-phase (apoptotic) cells was drastically increased at 12 h and 24 h, and that the G2/M-phase cells gradually increased at 6-24 h after treatment.

CONCLUSION

These results indicate that combined AsA and CRet treatment synergistically inhibits EAT cell growth through G2/M arrest and apoptosis induction via H2O2 generation at lower AsA concentrations; this carcinostatic effect cannot be exerted by AsA alone.

Immunohistochemical Characterization of S100A6 in the Murine Ovary

S100 proteins comprise a large family of Ca(2+)-binding proteins and exhibit a variety of intra- and extracellular functions. Despite our growing knowledge about the biology of S100 proteins in some tissues such as brain and smooth muscle, little is known about S100 proteins in the normal mammalian reproductive tissue. In the present study, we investigated the distribution pattern of S100A6 (alternatively named calcyclin) in the murine ovary by immunohistochemical study using specific antibody. S100A6 was localized substantially in the cytoplasm of luteal cells, with concomitant expression of S100A11, another S100 protein, but not in the other type of cells such as oocytes, follicle epithelial cells (granulosa cells), and cells of stroma including theca interna cells in the murine ovary. S100A6-immunoreactive corpora lutea (CLs) were divided into two types: homogeneously and heterogeneously stained CLs, and possibly they may represent differentiating and mature CL, respectively. Our regression analysis revealed that expression level of S100A6 positively correlated with that of cytochrome P450 11A, a steroidogenic enzyme in the heterogeously stained CL. These results suggested that S100A6 may contribute to differentiation of steroidogenic activity of luteal cells in a synergistic manner with S100A11 by facilitating some shared functions.

Dicalcin inhibits fertilization through its binding to a glycoprotein in the egg envelope in Xenopus laevis

Fertilization comprises oligosaccharide-mediated sperm-egg interactions, including sperm binding to an extracellular egg envelope, sperm penetration through the envelope, and fusion with an egg plasma membrane. We show that Xenopus dicalcin, an S100-like Ca(2+)-binding protein, present in the extracellular egg envelope (vitelline envelope (VE)), is a suppressive mediator of sperm-egg interaction. Preincubation with specific antibody greatly increased the efficiency of in vitro fertilization, whereas prior application of exogenous dicalcin substantially inhibited fertilization as well as sperm binding to an egg and in vitro sperm penetration through the VE protein layer. Dicalcin showed binding to protein cores of gp41 and gp37, constituents of VE, in a Ca(2+)-dependent manner and increased in vivo reactivity of VE with a lectin, Ricinus communis agglutinin I, which was accounted for by increased binding ability of gp41 to the lectin and greater exposure of gp41 to an external environment. Our findings strongly suggest that dicalcin regulates the distribution of oligosaccharides within the VE through its binding to the protein core of gp41, probably by modulating configuration of oligosaccharides on gp41 and the three-dimensional structure of VE framework, and thereby plays a pivotal role in sperm-egg interactions during fertilization.

Platinum nanocolloid-supplemented hydrogendissolved water inhibits growth of human tongue carcinoma cells preferentially over normal cells

AIM

Hydrogen-dissolved water (HD-water) or platinum nanocolloid (Pt-nc) has been individually expected as a new therapeutic agent for oxidative stress-related diseases, whereas little is known about their combined effects on cancer, which were elucidated in the present study.

METHODS

HD-water was prepared by microporous gas bubbling, and supplemented with Pt-nc consisting of 0.003-1 ppm Pt and PVP polymers. Antioxidant activities were examined by 1, 1-diphenyl-picrylhydrazyl (DPPH)-radicalscavenging assay. Cytotoxic activities were examined by culturing of tumor and normal cell lines, respectively.

RESULTS

HD-water accelerated the Pt-nc-based DPPH-radical scavenging. Pt-nc-supplemented HD-water inhibited either colony formation efficiencies or colony sizes of human tongue carcinoma cells HSC-4, in contrast to no effects of HD-water alone, Pt-nc alone or Pt-absent PVP, but not appreciably inhibit normal human tongue epithelial-like cells DOK. Pt-nc-supplemented HD-water also suppressed cell population growth of HSC-4 cells of near-confluence (at higher cell densities) in view of decreases in either cell numbers or mitochondrial function, although less markedly than colony formation starting from a sparse-cell state (at lower cell densities). Dissolved hydrogen, oxygen concentration or oxido-reduced potentials of HD-water was decreased, rather decreased or increased by Pt-nc addition, respectively.

CONCLUSIONS

Anti-cancer activity of Pt-nc-supplemented HD-water was shown by its preferential cell-growth inhibition to human tongue carcinoma cells HSC-4 over normal human tongue cells DOK, and might be partly attributed to HD-water-caused enhancement of Pt-nc-relevant antioxidant ability. Pt-nc-supplemented HD-water is expected as a novel agent against human tongue cancers due to its cancer progression-repressive abilities.

Biological safety of liposome-fullerene consisting of hydrogenated lecithin, glycine soja sterols, and fullerene-C60 upon photocytotoxicity and bacterial reverse mutagenicity

Various water-soluble derivatives of fullerene-C60 (C60) have been developed as detoxifiers for reactive oxygen species (ROS), whereas C60 incorporated in liposome (Lpsm) has not been reported yet. We prepared the liposome-fullerene (0.2% aqueous phase, Lpsm-Flln) which was composed of hydrogenated lecithin, glycine soja (soybean) sterols, and C60 in the weight ratio of 89.7:10:0.3, then examined the photocytotoxicity and bacterial reverse mutagenicity, as comparing with the Lpsm containing no C60. Photocytoxicity of Lpsm-Flln or Lpsm was examined using Balb/3T3 fibroblastic cells at graded doses of 0.49-1000 microg/mL under the condition of UVA- or sham-irradiation. The cells were irradiated with UVA (5 J/cm2, 320-400 nm, lambda max = 360 nm) at room temperature for 50 min. The resultant cell viability (% of control) did not decrease dose-dependently to 50% or less regardless of the UVA-irradiation. These results show that Lpsm-Flln or Lpsm does not possess photocytotoxicity to Balb/3T3 fibroblasts, and Lpsm-Flln may not exert a UVA-catalytic ROS-increasing action. A possibility for the reverse mutation by Lpsm-Flln or Lpsm was examined on four histidine-demanding strains of Salmonella typhimurium and a tryptophan-demanding strain of Escherichia coli. As for the dosages of Lpsm-Flln or Lpsm (313-5000 microg/plate), the dose-dependency of the number of reverse mutation colonies of each strain did not show a twice or more difference versus the negative control regardless of the metabolic activation, and, in contrast, marked differences for five positive controls (sodium azide, N-ethyl-N'-nitro-N-nitrosoguanidine, 2-nitrofluorene, 9-aminoacridine, and 2-aminoanthracene). The growth inhibition of bacterial strains and the deposition of Lpsm-Flln or Lpsm were not found. As a result, the bacterial reverse mutagenicity of Lpsm-Flln or Lpsm was judged to be negative under the conditions of this test. Thus, Lpsm-Flln and Lpsm may not give any significant biological toxic effects, such as photocytotoxicity and bacterial reverse mutagenicity.

Cloning and characterization ofXenopusdicalcin, a novel S100-like calcium-binding protein inXenopuseggs

To contribute to the study of the calcium-signaling mechanism of egg, we cloned and characterized a 26 kDa Ca(2+)-binding protein from Xenopus laevis eggs, a homologue of Rana catesbeiana dicalcin (renamed from p26olf) that was isolated from the olfactory epithelium. The primary structure of Xenopus dicalcin shows approximately 61% identity to that of Rana dicalcin and consists of two S100-like regions aligned in tandem, as seen in Rana dicalcin. Genomic Southern blot analysis indicated that Xenopus dicalcin is a unique orthologue of Rana dicalcin. Northern blot analysis showed that Xenopus dicalcin mRNA is expressed in Xenopus eggs and also in other tissues. These results indicated that Xenopus dicalcin is a novel S100-like Ca(2+)-binding protein in Xenopus eggs.

S100-annexin complexes--biology of conditional association

S100 proteins and annexins both constitute groups of Ca2+-binding proteins, each of which comprises more than 10 members. S100 proteins are small, dimeric, EF-hand-type Ca2+-binding proteins that exert both intracellular and extracellular functions. Within the cells, S100 proteins regulate various reactions, including phosphorylation, in response to changes in the intracellular Ca2+ concentration. Although S100 proteins are known to be associated with many diseases, exact pathological contributions have not been proven in detail. Annexins are non-EF-hand-type Ca2+-binding proteins that exhibit Ca2+-dependent binding to phospholipids and membranes in various tissues. Annexins bring different membranes into proximity and assist them to fuse, and therefore are believed to play a role in membrane trafficking and organization. Several S100 proteins and annexins are known to interact with each other in either a Ca2+-dependent or Ca2+-independent manner, and form complexes that exhibit biological activities. This review focuses on the interaction between S100 proteins and annexins, and the possible biological roles of these complexes. Recent studies have shown that S100-annexin complexes have a role in the differentiation of gonad cells and neurological disorders, such as depression. These complexes regulate the organization of membranes and vesicles, and thereby may participate in the appropriate disposition of membrane-associated proteins, including ion channels and/or receptors.

Promotive effects of hyperthermia on the cytostatic activity to Ehrlich ascites tumor cells by diverse delta-alkyllactones

AIM

To evaluate promotive effects of hyperthermia on antitumor activity of new delta-alkyllactones (DALs) of low molecular weight (184-254 Da), chemically synthesized, which are different from natural macrocyclic lactones of high molecular weight (348-439 Da), such as camptothecin and sultriecin.

METHODS

A suspension of Ehrlich ascites tumor (EAT) cells was mixed with a DAL in a glass tube, heated at 37 or 42 degrees C for 30 min in a water bath, and cultured at 37 degrees C for 20 or 72 h. Cell viability was measured by the mitochondrial dehydrogenase- based WST-1 assay. DALs incorporated into EAT cells was extracted and measured by gas-liquid chromatography.

RESULTS

The reduction of cell viability by DALs was markedly enhanced upon the treatment at 42 degrees C compared to that at 37 degrees C. At 37 degrees C, delta-hexadecalactone (DH16:0) and delta-tetradecalactone (DTe14:0) displayed cytostatic activity (at 100 microM survival level: 20.7%, 66.1%; at 50 microM--41.2%, 82.4%, respectively). Their activity was more marked at 42 degrees C (at 100 microM 10.6%, 27.6%; at 50 microM 30.6, 37.5%, ibid). The other DALs, delta-undecalactone (DU11:0), delta-dodecalactone (DD12:0), and delta-tridecanolactone (DTr13:0) were almost ineffective. Evaluation of survival rate in the cells treated for 30 min by DALs with the next culturing of EAT cells for 72 h resulted in the enhanced carcinostatic activity of DH16:0 and DTe14:0 even at concentrations as low as 25 microM at either 37 degrees C (18.5%, 78.5%, ibid) or 42 degrees C (5.0%, 42.0%, ibid), but the others exhibited slight activity or none. DH16:0 was effective at either 37 degrees C (36.0%) or 42 degrees C (23.0%) even at a lower dose of 10 microM. At the same time only the most cytostatic DH16:0 was incorporated into EAT cells and the rate of incorporation was more at 42 degrees C than at 37 degrees C.

CONCLUSION

Delta-hexadecanolactone (DH16:0) exhibited the most cytostatic effect that was significantly enhanced by hyperthermia. It allows to consider it as a potent antitumor agent, especially in combination with hyperthermia.

Comprehensive interaction of dicalcin with annexins in frog olfactory and respiratory cilia

Dicalcin (renamed from p26olf) is a dimer form of S100 proteins found in frog olfactory epithelium. S100 proteins form a group of EF-hand Ca(2+)-binding proteins, and are known to interact with many kinds of target protein to modify their activities. To determine the role of dicalcin in the olfactory epithelium, we identified its binding proteins. Several proteins in frog olfactory epithelium were found to bind to dicalcin in a Ca(2+)-dependent manner. Among them, 38 kDa and 35 kDa proteins were most abundant. Our analysis showed that these were a mixture of annexin A1, annexin A2 and annexin A5. Immunohistochemical analysis showed that dicalcin and all of these three subtypes of annexin colocalize in the olfactory cilia. Dicalcin was found to be present in a quantity almost sufficient to bind all of these annexins. Colocalization of dicalcin and the three subtypes of annexin was also observed in the frog respiratory cilia. Dicalcin facilitated Ca(2+)-dependent liposome aggregation caused by annexin A1 or annexin A2, and this facilitation was additive when both annexin A1 and annexin A2 were present. In this facilitation effect, the effective Ca(2+) concentrations were different between annexin A1 and annexin A2, and therefore the dicalcin-annexin system in frog olfactory and respiratory cilia can cover a wide range of Ca(2+) concentrations. These results suggested that this system is associated with abnormal increases in the Ca(2+) concentration in the olfactory and other motile cilia.

Effects of ethyl-esterization, chain-lengths, unsaturation degrees, and hyperthermia on carcinostatic effect of omega-hydroxylated fatty acids

AIM

To evaluate promotive effect of hyperthermia on the carcinostatic activity of synthesized omega-hydroxy fatty acids (omega HFAs) and their ethylesters agaist Ehrlich ascites tumor (EAT) cells.

METHODS

EAT cells were cultured with either omegaHFAs or their ethylester derivatives in a water bath at either 37 degrees C or 42 degrees C for 30 min, followed by incubation in a CO2 incubator for 20 or 72 h. Mitochond-rial dehydrogenase-based WST-1 assay and trypan blue dye exclusion assay were then conducted after incubation. Morphological changes were observed by scanning electron microscopy (SEM).

RESULTS

Omega-HFA having a saturated 16-carbon straight-chain (omega H16:0) was the most carcinostatic (at 37 degrees C - viability level: 60.0%; at 42 degrees C - 49.6% (WST-1)) among saturated and unsaturated omegaHFAs with 12, 15 or 16 carbon atoms, when administrated to EAT cells at 100 microM for 20 h. Carcinostatic activity was markedly enhanced by ethyl-esterization of saturated fatty acids, such as omegaH16:0 (at 37 degrees C - 42.3%; at 42 degrees C - 11.2%, ibid) and omegaH15:0 (at 37 degrees C - 74.6%; at 42 degrees C - 25.3%, ibid), and their unsaturated counterparts were extremely effective only in combination with hyperthermia. Prolongation of the incubation period to 72 h at the same concentration increased appreciably their carcinostatic effect (omega H16:0 ethylesther: 1.3%; omegaH15:0 ethylesther: 8.0%). These values were also supported by dye exclusion assay. The carcinostatic activity enhanced more markedly by hyperthermia (1.2%; 2.1%, ibid). SEM shows that omegaH16:0 ethylester-exposed EAT cells underwent extensive injury, such as deformation of cell structure or disappearance of microvilli.

CONCLUSIONS

omega H16:0 ethylester possesses high carcinostatic activity in vitro in combination with hyperthermia and may be utilized as potent anticancer therapeutic agent.

Lack of hippocalcin causes impairment in Ras/extracellular signal-regulated kinase cascade via a Raf-mediated activation process

Hippocalcin (Hpca) is a member of the neuronal calcium sensor protein family and is highly expressed in hippocampal neurons. Hpca-deficient (Hpca(-/-)) mice display a defect in cAMP response element-binding protein (CREB) activation associated with impaired spatial and associative memory. Here we examine the involvement of Hpca in the extracellular signal-regulated kinase (ERK) cascade leading to CREB activation, because application of PD98059, a broad ERK cascade inhibitor, has resulted in similar levels of CREB activation in Hpca(-/-) hippocampus. N-methyl-D-aspartate (NMDA)- and KCl-induced phosphorylation of ERK was significantly attenuated in Hpca(-/-) hippocampal slices, as was ionomycin-induced phosphorylation of ERK, whereas forskolin and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) stimulation yielded indistinguishable levels of ERK phosphorylation in both wild-type and Hpca(-/-) slices. In an in vitro reconstitution assay system, recombinant Hpca affected neither Raf-1 protein kinase activity with recombinant MEK-1 as a substrate nor MEK-1 kinase activity with ERK2 as a substrate. Activation of Ras by NMDA and KCl stimulation of hippocampal slices showed no obvious changes between the two genotypes; however, phosphorylation of Raf-1 was significantly lower in Hpca(-/-) slices. These results suggest that Hpca plays an important role in the activation of Raf conducted by Ras.

Promotive effects of hyperthermia on the inhibition of DNA synthesis in ehrlich ascites tumor cells by eicosapentaenoic and docosahexaenoic acids

AIM

To evaluate inhibitory effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on DNA synthesis in combination with hyperthermia in vitro.

METHODS

A suspension of Ehrlich ascites tumor cells (EAT) was mixed with DHA or EPA in a glass tube, heated at 37 degrees C, 40 degrees C, or 42 degrees C for 1 h in a water bath, and cultured at 37 degrees C for 19 or 96 h. DNA synthesis was assayed by monitoring of the incorporation of [3H]-thymidine into the acid-insoluble fraction. DHA or EPA incorporated into EAT cells was extracted and measured by thin-layer chromatography and gas-liquid chromatography.

RESULTS

The inhibition of DNA synthesis by EPA or DHA increased markedly upon the treatment at 42 degrees C and 40 degrees C compared to that at 37 degrees C. At 37 degrees C, inhibitory action of EPA was more potent than that of DHA at low concentrations (at 50 microM -- DNA synthesis level: EPA, 63.1%; DHA, 87.9%), whereas inhibitory action of DHA was higher at 150 muM (16.7%, 4.4%, ibid.). The effect of DHA compared to EPA was more marked at 40 degrees C (29.0%, 19.2% at 100 microM) or 42 degrees C (19.7%, 10.6% at 100 microM). Evaluation of DNA synthesis rate in the cells treated for 1 h by EPA or DHA with the next culturing of EAT cells for 19 h resulted in the enhanced inhibitory activity of EPA even at concentrations as low as 50 microM at either 37 degrees C (0.5%, 11.3%) or 42 degrees C (0.6%, 4.5%), which in these conditions was higher than that of DHA. At the same time the rate of incorporation of EPA in EAT cells at 37 degrees C or 42 degrees C was lower than that of DHA.

CONCLUSION

Administration of DHA or EPA in vitro significantly inhibit DNA synthesis, and such effect is enhanced by combination of PUFAs with hyperthermia.

Odorant-induced activation of extracellular signal-regulated kinase/mitogen-activated protein kinase in the olfactory bulb promotes survival of newly formed granule cells

Extracellular signal-regulated kinase 1/2 (Erk1/2)/mitogen-activated protein (MAP) kinase (MAPK) plays a significant role in neuronal survival, including odorant-induced, activity-dependent survival of olfactory sensory neurons in the main olfactory epithelium. Here, we examined the role of MAPK for the survival of neurons in the olfactory bulb. To study odorant-induced activation of MAPK in the olfactory bulb, mice were exposed to odorants in vivo, and MAPK was assayed. Exposure of mice to some odorants in vivo activated MAPK in granule cells 10 min after exposure. Activation of MAPK was particularly evident in the nucleus and dendrites of granule cells. Because MAPK activation can augment neuronal survival, odorant enhancement of granule cell survival was monitored by bromodeoxyuridine (BrdU) incorporation. Long-term exposure to odorants increased the survival of newly formed granule cells as well as the number of granule cells that were both BrdU+ and phospho-Erk+. Inhibition of MAPK by administration of SL327 in vivo blocked the odorant-induced increase in newly formed granule cells, suggesting that activation of MAPK promotes the survival of granule cells in the olfactory bulb. Studies using cultured granule cells confirmed that activation of MAPK in granule cells protects them against strong apoptotic signals. These data suggest that stimulation of MAPK in olfactory bulb granule cells by some odorants may contribute to the survival of newly formed granule cells caused by odorant exposure.

Frog p26olf, a molecule with two S100-like regions in a single peptide

An S100-like calcium-binding protein, p26olf, was originally isolated from the frog (Rana Catesbeiana) olfactory epithelium with four chromatographical steps. The primary structure of p26olf contains two S100-like regions aligned in tandem with four functional EF-hands. At 100 mM K(+), wild-type p26olf binds Ca(2+) with a Kd value of 22 microM and a Hill coefficient of 2.0. Each EF-hand seems to have different affinity for Ca(2+): it is high in EF-A and -B and low in EF-C and -D. In our Ca(2+)-binding model, the order of Ca(2+)-binding to p26olf is EF-B, EF-A, EF-C, and EF-D. Expression of mRNA of p26olf is detected in various frog tissues: it is high in the olfactory epithelium, lung, and spleen, moderate in brain, retina, heart, and kidney, and low in liver and muscle. Immunohistochemical studies revealed that p26olf is prominently localized in the cilia of both olfactory and lung respiratory epithelium and especially enriched in the distal segment of the olfactory cilia. Several proteins in the olfactory cilia bind to p26olf in the presence of Ca(2+), suggesting that they are possible target proteins of p26olf. One of these target proteins is immunologically identified as a beta-adrenergic receptor kinase-like protein. In the olfactory cilia, p26olf may have some roles in the olfactory transduction or adaptation through interaction with this beta-adrenergic receptor kinase-like protein.

Involvement of claudin-1 in the beta-catenin/Tcf signaling pathway and its frequent upregulation in human colorectal cancers

Accumulation of beta-catenin in cytoplasm and nuclei is frequently observed in a wide variety of tumors arising, for example, in the colon, liver, uterus, or brain. In association with Tcf/LEF transcription factors, beta-catenin regulates expression of genes involved in the Wnt/wingless signaling pathway, but the precise mechanisms are unclear. Here we report evidence that the claudin-1 (CLDNI) gene is one of the genes regulated by beta-catenin. Not only did expression of CLDN1 decrease significantly in response to reduction of intracellular beta-catenin by adenovirus-mediated transfer of wild-type APC into the APC-deficient colon cancer cells, but also two putative Tcf4 binding elements in the 5' flanking region of CLDN1 were confirmed to be responsible for activating its transcription. We documented increased expression of CLDN1 in all 16 primary colorectal cancers we examined, compared with adjacent noncancerous mucosae. Furthermore, immunohistochemical staining demonstrated that claudin-1 was weakly stained at apical boarder of lateral membrane of noncancerous epithelial cells and that it was strongly stained at all cell-cell boundaries and in the cytoplasms of cancer cells. Our results imply that claudin-1 is involved in the beta-catenin-Tcf/LEF signaling pathway, and that increased expression of claudin-1 may have some role in colorectal tumorigenesis.

Catheter dysfunction and thrombosis of double-lumen hemodialysis catheters placed in the femoral vein

OBJECTIVE

Intraluminal thrombosis of the catheter was thought to be a major cause of catheter dysfunction. We evaluated if thrombi appear in the luminal side or outside of the catheters placed in the femoral vein in 21 hemodialysis patients.

METHODS

23 double-lumen catheter (25 cm long and 4 mm diameter polyurethane) strippings were consecutively performed. Mean catheter dwell time was 17.9 +/- 11.2 days (2-45 days). The femoral vein was observed with ultrasound echography, and thrombo-venous ratio (thrombus diameter/vein diameter) was calculated. X-rays were also taken to clearly visualize the thrombi followed by contrast medium injection through the catheter.

RESULTS

Tube-shaped thrombi were echographically detected in 22 of 23 catheters (95.7%) when the catheter was stripped. Ten catheters (43.5%) were stripped due to the reduced blood flow, and tube-shaped thrombi were observed in the femoral vein, whereas no thrombus was found in the intraluminal side of the catheter. In 7 of 23 patients (30.4%) with leg edema on the same side of the catheter, the thrombovenous ratio was 78.9 +/- 7.4%, which was higher than that in the patients without leg edema (52.1 +/- 11.1%).

CONCLUSION

The tube-shaped thrombi, formed around the double-lumen catheter, may cause catheter dysfunction and reduced venous return of the lower legs. The catheter should be removed as soon as thrombosis is diagnosed, especially when accompanied by leg edema.

Calcium-dependent phosphorylation of a protein in the frog olfactory cilia

In the cilia of vertebrate olfactory sensory neurons, cytoplasmic Ca(2+) concentration increases in response to odorant stimulation, and this increase has been implicated to have important roles in the regulation of olfactory responses. Since protein phosphorylation is often a regulatory mechanism of biological reactions, we explored the effect of Ca(2+) on phosphorylation reactions in the frog olfactory cilia. First, we found that a 45-kDa phosphoprotein (p45) is predominantly phosphorylated in vitro in the isolated cilia in a Ca(2+)-dependent manner. However, later studies showed that the phosphorylation level of p45 is controlled by a dynamic equilibrium between phosphorylation and dephosphorylation. Although both activities are enhanced at high Ca(2+) concentrations (K(1/2) = approximately 2 microM in both reactions), the enhancement of dephosphorylation is relatively greater than that of phosphorylation. As a result, the steady phosphorylation level of p45 is lower at high than at low Ca(2+) concentration. The phosphorylation/dephosphorylation equilibrium was founed to involve protein kinases sensitive to zinc and heparin, and an unknown phosphatase(s). The present result suggests the presence of a novel Ca(2+)-signaling pathway that involves phosphorylation of p45 in the olfactory cilia.

Yersinia pseudotuberculosis infection in breeding monkeys: detection and analysis of strain diversity by PCR

In the last three decades, several monkeys reared in outdoor/indoor-outdoor breeding colonies and cages of the Primate Research Institute, Kyoto University, died of yersiniosis caused by Yersinia pseudotuberculosis, necessitating introduction of a method to detect the bacteria rapidly and thus allow preventive measures to be undertaken. A rapid nested polymerase chain reaction (PCR) method for identification of Y. pseudotuberculosis in fecal samples and a random amplified polymorphic DNA (RAPD)-PCR approach for distinguishing between bacterial strains were therefore developed. Yersinia pseudotuberculosis isolates from monkey specimens were found to be classifiable into several types. To determine the source of infection, hundreds of fecal samples of wild rats, pigeons, and sparrows were collected from around the breeding colonies and cages, and subjected to PCR analyses. Yersinia pseudotuberculosis was detected in 1.7% of the fecal samples of wild rats. The DNA fingerprints of the bacteria revealed by RAPD-PCR were the same as that of one strain isolated from macaques, suggesting the wild rat to be a possible source of infection.

Calcium-binding by p26olf, an S100-like protein in the frog olfactory epithelium

Frog p26olf is a novel S100-like Ca2+-binding protein found in olfactory cilia. It consists of two S100-like domains aligned sequentially, and has a total of four Ca2+-binding sites (known as EF-hands). In this study, to elucidate the mechanism of Ca2+-binding to each EF-hand (named EF-A, -B, -C and -D from the N-terminus of p26olf), we examined Ca2+-binding in wild-type p26olf and also in its mutants in which a glutamate at the -z coordinate position within each Ca2+-binding loop was substituted for a glutamine. Flow dialysis experiments showed that the wild-type binds nearly four Ca2+ per molecule maximally, while all the mutants bind approximately three Ca2+. Although EF-B and -D are p26olf-specific EF-hands and their role in Ca2+-binding is not known, the result unequivocally showed that they actually bind Ca2+. The overall Ca2+-binding affinity decreased in the three mutants. The decrease was very large in the mutants of EF-A and -B, which suggested that the Ca2+-affinities are high in EF-A and -B in the wild-type. Assuming the presence of four steps of Ca2+-binding, we determined the dissociation constant of each step in wild-type p26olf. To assign which step takes place at which EF-hand, we measured the antagonistic effect of K+ on each step, as the effect of K+ is thought to be a function of the number of the carboxyl groups in an EF-hand. Although the actual Ca2+-binding mechanism may not be so simple, this study together with the mutation study suggested a tentative Ca2+-binding model of p26olf: the order of Ca2+-binding to p26olf is EF-B, EF-A, EF-C and EF-D. Based on these results, we speculate that similar Ca2+-binding takes place in an S100 dimer.

Serum levels of macrophage colony-stimulating factor and aortic calcification in hemodialysis patients

Hemodialysis (HD) patients have accelerated atherosclerosis. Recent reports have shown that aortosclerosis is more frequently observed in HD patients than in healthy subjects. Macrophage colony-stimulating factor (M-CSF) secreted by activated macrophages may be involved in the process of aortosclerosis in HD patients. To understand the mechanism behind the increased incidence of aortosclerosis in HD patients, we examined the relationships between serum M-CSF levels and aortic calcification index (ACI) estimated by CT scan. A significant increase in serum M-CSF concentrations was found in HD patients (3.8 +/- 0.2 ng/ml) as compared with controls (1.5 +/- 0.1 ng/ml). No significant differences were observed between chronic glomerulonephritis and diabetes mellitus groups of patients. We also found no significant differences between the groups using different membranes (triacetate 3.8 +/- 0.2 ng/ml vs. polysulfone 3.8 +/- 0.4 ng/ml). There was no correlation between serum M-CSF concentrations and clinical parameters such as age, duration of HD, blood pressure, serum concentrations of nitrogen, creatinine, cholesterol, triglyceride, LDL, Ca x P products, and intact parathyroid hormone. A positive correlation was observed between serum M-CSF levels and ACI in HD patients (r = 0.596, p < 0.01). These results suggest that M-CSF may be involved in the process of aortosclerosis in HD patients.

Regulation of mammalian phospholipase D2: interaction with and stimulation by G(M2) activator

We have previously reported that a heat-stable activator for ganglioside metabolism, G(M2) activator, potently stimulates ADP-ribosylation factor (ARF)-dependent phospholipase D (PLD) activity (presumably PLD1) in an in vitro system [Nakamura, Akisue, Jinnai, Hitomi, Sarkar, Miwa, Okada, Yoshida, Kuroda, Kikkawa and Nishizuka (1998) Proc. Natl. Acad. Sci. U.S.A. 95, 12249-12253]. However, little is known about the regulation of PLD2. In the present studies we have investigated the regulation of PLD2 by G(M2) activator and various other regulators including ARF. PLD2 was potently stimulated in vitro by G(M2) activator in a time- and dose-dependent manner. Neither ARF nor protein kinase C caused any significant changes in PLD2 activity. Importantly, PLD2 responsiveness to ARF was greatly enhanced by G(M2) activator, suggesting a possible role for G(M2) activator as a coupling factor. G(M2) activator was also demonstrated to physically associate with PLD2 in a stoichiometric manner. Further, PMA stimulation of COS-7 cells overexpressing both G(M2) activator and PLD2 resulted in a marked increase in the association of the two molecules. Interestingly, ARF association with PLD2 was greatly increased by G(M2) activator. Moreover, G(M2) activator enhanced PMA-induced PLD activity in a synergistic manner with ARF in streptolysin-O-permeabilized, cytosol-depleted HL-60 cells, suggesting that G(M2) activator may regulate PLD in a concerted manner with other factors, including ARF, inside the cells.

The relationship between UVB screening and cytoprotection by microcorpuscular ZnO or ascorbate against DNA photodamage and membrane injuries in keratinocytes by oxidative stress

Decreased cell viability and increased formation of cyclobutane-type pyrimidine dimers (CPDs) in DNA of UVB-irradiated keratinocytes were shown to be appreciably restored by the addition of w/o emulsion of microcorpuscular zinc oxide (mcZnO) with a corpuscle diameter of 0.15 microm. The cytoprotection was exerted only by 20 wt/wt% mcZnO at levels equivalent to 40- to 100-microm-thick emulsion layers, which screened 90-92% of the incident UVB. However, protection was not seen by mcZnO below 20-microm thickness, which, unexpectedly, screened 79% of the incident radiation. This suggests that thorough UVB screening is necessary for cytoprotection. This may be attributable to involvement of intracellular reactive oxygen species (ROS) secondarily generated from UVB-irradiated mcZnO. Intracellular ROS was increased in mcZnO-added cells in a time-dependent manner even after UVB irradiation, contrasting with reduction of intracellular ROS in ascorbic acid-added cells. UVB-induced disruption of cell membrane integrity was reduced by mcZnO at 100-microm thickness, equivalent to the addition of ascorbic acid of 50 microM. Thus, mcZnO was thought to be cytoprotective through reductions of intracellular ROS generation, CPD formation and cell membrane disintegration when added so abundantly so as to achieve UVB-screening more than 90%.

Identification of AF17 as a downstream gene of the beta-catenin/T-cell factor pathway and its involvement in colorectal carcinogenesis

To elucidate the molecular mechanism of colorectal carcinogenesis, we have been attempting to isolate genes involved in the beta-catenin/T-cell factor pathway. In the experiments reported here, analysis by cDNA microarray indicated that AF17, a fusion partner of the MLL gene in acute leukemias with t(11;17)(q23;q21), was transactivated according to accumulation of beta-catenin. Expression of AF17 was significantly enhanced in 8 of the 12 colorectal cancer tissues examined. Introduction of a plasmid designed to express AF17 stimulated growth of NIH3T3 cells, and fluorescence-activated cell sorter analysis indicated that the AF17 regulation of cell-cycle progression was occurring mainly at the G(2)-M transition. Our results suggest that the AF17 gene product is likely to be involved in the beta-catenin-T-cell factor/lymphoid enhancer factor signaling pathway and to function as a growth-promoting, oncogenic protein. These findings should aid development of new strategies for diagnosis, treatment, and prevention of colon cancers and acute leukemias by clarifying the pathogenesis of these conditions.

Paramagnetic water-soluble metallofullerenes having the highest relaxivity for MRI contrast agents

Water-soluble gadolinium (Gd) endohedral metallofullerenes have been synthesized as polyhydroxyl forms (Gd@C(82)(OH)(n)(), Gd-fullerenols) and their paramagnetic properties were evaluated by in vivo as well as in vitro for the novel magnetic resonance imaging (MRI) contrast agents for next generation. The in vitro water proton relaxivity, R(1) (the effect on 1/T(1)), of Gd-fullerenols is significantly higher (20-folds) than that of the commercial MRI contrast agent, Magnevist (gadolinium-diethylenetriaminepentaacetic acid, Gd-DTPA) at 1.0 T close to the common field of clinical MRI. This unusually high proton relaxivity of Gd-fullerenols leads to the highest signal enhancement at extremely lower Gd concentration in MRI studies. The strong signal was confirmed in vivo MRI at lung, liver, spleen, and kidney of CDF1 mice after i.v. administration of Gd-fullerenols at a dose of 5 micromol Gd/kg, which was 1/20 of the typical clinical dose (100 micromol Gd/kg) of Gd-DTPA.

Correlation of DNA synthesis-inhibiting activity and the extent of transmembrane permeation into tumor cells by unsaturated or saturated fatty alcohols of graded chain-length upon hyperthermia

The carcinostatic activity has been studied for fatty acids of diverse species but scarcely for fatty alcohols. Three unsaturated fatty alcohols at 35-50 microM inhibited DNA synthesis and the proliferation of tumor cells by a combination with hyperthermia to greater extents in the order: oleyl (C18:1)-> linoleyl (C18:2)-> alpha-linolenyl (C18:3) alcohol, which is an order inverse to that known for the corresponding fatty acids (4). In contrast, two saturated fatty alcohols, palmityl (C16:0)- and stearyl (C18:0) alcohols, did not inhibit at the same concentrations. At 100 microM, palmityl alcohol inhibited, whereas stearyl alcohol did not. The effective fatty alcohols appreciably permeated the cells. The inhibition of the unsaturated fatty alcohols on DNA synthesis and proliferation was nearly proportional to the amount of their intercellular accumulation at 37 degrees C or 42 degrees C; the most inhibitory, oleyl alcohol, was the most membrane-permeable, whilst inversely the least inhibitory, alpha-linolenyl alcohol, was the least permeable. A proportional correlation was not observed for saturated fatty alcohols; palmityl alcohol underwent an approximate 2-fold more abundant accumulation than other fatty alcohols, but was weakly inhibitory. Thus, oleyl alcohol may exert an antitumor action via appropriately efficient transmembrane permeation and a combination with hyperthermia.

The influence of rearing conditions on the physical growth of captive Japanese macaques (Macaca fuscata)

To clarify the influence of rearing conditions on the growth of various body parts of Japanese macaques (Macaca fuscata), two groups reared under different conditions, i.e., a group born and reared in open enclosures (Enclosure group) and another consisting of macaques born and reared in cages (Caged group), were somatometrically analyzed. Somatometric data on 36 measures of various body parts were collected from 77 males and 92 females. Growth in many body parts was smaller in the Caged group than in the Enclosure group. Body parts that exhibited large incremental increases were more sensitive to differences in rearing space at the infantile growth stage in both sexes. Recovery from delayed growth at the pubertal growth stage was found in many body parts. However, the size of some locomotor elements such as the wrist and hand, and ankle and foot strongly reflected limitations of space and changes due to this were irreversible. Females were more sensitive than males to such differences in rearing conditions. We conclude that open enclosures with ample rearing space are necessary for the innate growth of Japanese macaques to occur.

An outbreak of food poisoning due to egg yolk reaction-negative Staphylococcus aureus

An outbreak of staphylococcal food poisoning due to an egg yolk (EY) reaction-negative strain occurred in Japan. Twenty-one of 53 dam construction workers who ate boxed lunches prepared at their company cafeteria became ill, and eight required hospital treatment. The outbreak showed a typical incubation time (1.5-4 h with a median time of 2.7 h) and symptoms (vomiting and diarrhea) of staphylococcal food poisoning. Staphylococcus aureus, which produces staphylococcal enterotoxin (SE) A, was isolated from four fecal specimens of eight patients tested. Scrambled egg in the boxed lunches contained 20-40 ng/g of SEA, and 3.0 x 10(9)/g of viable S. aureus cells that produced this toxin. All isolates from patients and the food were EY reaction-negative, coagulase type II, and showed the same restriction fragment length polymorphism (RFLP) pattern. We concluded that the outbreak was caused by scrambled egg contaminated with EY reaction-negative S. aureus. In Japan, outbreaks of staphylococcal food poisoning are mainly caused by EY reaction-positive S. aureus, and EY reaction-negative colonies grown on agar plates containing EY are usually not analyzed further for detection of S. aureus. The present outbreak suggested that EY reaction-negative isolates should be subjected to further analysis to detect the causative agents of staphylococcal food poisoning.