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The decomposition and rehydrogenation of γ-Mg(BH4)2ball milled together with 2 mol % of Ni-based additives, Ninano, NiCl2, NiF2, and Ni3B, has been investigated during one hydrogen desorption–absorption cycle. Under the applied ball-milling conditions, no mechanochemical reactions between γ-Mg(BH4)2and Niaddwere observed. Hydrogen desorption carried out at temperatures of 220–264 °C resulted for all samples in partial decomposition of Mg(BH4)2and formation of amorphous phases, as seen by powder X-ray diffraction (PXD). PXD analysis after rehydrogenation at temperatures of 210–262 °C and at pressures between 100 and 155 bar revealed increased fractions of crystalline β-Mg(BH4)2, indicating a partial reversibility of the composite powders. The highest amount of [BH4]−is formed in the composite containing Ni3B. Analysis by X-ray absorption spectroscopy performed after ball milling, after desorption, and after absorption shows that the Ni3B additive remains unaffected, whereas NiCl2and NiF2additives react with Mg(BH4)2during the hydrogen desorption–absorption and form compounds with a local structure very similar to that of amorphous Ni3B. Multinuclear NMR spectroscopy confirms the partial reversibility of the system as well as the formation of [B10H10]2–during hydrogen absorption. The presence of [BnHn]2–(n= 10, 12) was also detected by infrared (IR) spectroscopy of the dehydrogenated and rehydrogenated samples. The IR measurements give no clear indication that ions containing B–H–B bridged hydrogen groups were formed during the H-sorption cycle.

Abstract:  We measured primary production by phytoplankton in the south basin of Lake Baikal, Russia, by in situ 13C-bicarbonate incubations within the period March–October in two consecutive years (1999 and 2000). Primary production was highest in the subsurface layer, possibly due to near-surface photoinhibition of photosynthesis, even under 0.8 m of ice cover in March. Areal primary production varied from 79 mg C m−2 day−1 (March) to 424 mg C m−2 day−1 (August), and annual primary production was roughly estimated as 75 g C m−2 year−1, both of which are within the lower range of previous estimates. Size fractionation measurements revealed that phytoplankton in the <20 μm fraction accounted for 72%, 96%, and 85% of total primary production in March, August, and October, respectively. The contribution of picophytoplankton (<2 μm) to total primary production ranged from 41% to 62%. A large fraction (82%–98%) of particulate organic carbon was associated with particles in the <20 μm fraction. These results suggest that nano- and picophytoplankton play an important role as primary producers in the pelagic ecosystem of Lake Baikal.

Abstract:  To clarify the variations in environmental factors and biological characteristics of eutrophic, brackish, meromictic Lake Abashiri, Japan, we studied long-term variations in concentrations of chloride and nutrients in lake water and characteristics of their supply. This lake has an anoxic layer containing much chloride, nutrients, and sulfide. Although a dense Anabaena bloom appeared in the lake every summer before 1986, the bloom did not appear after upwelling from the bottom layer (a blue tide) occurred in spring 1987. A dense layer of photosynthetic bacteria (Chlorobium sp.) formed at the top of the anoxic layer from 1989 to May 1992. The concentrations of nutrients and chloride in the oxygenic layer were determined by the balance between nutrients from influent rivers, including dissolved inorganic nitrogen, and matter supplied from the anoxic layer, including chloride and dissolved inorganic phosphorus. These influences controlled the dominant phytoplankton species and their biomass. The appearance of an Anabaena bloom in Lake Abashiri is promoted by nitrogen limitation caused by decreased loading from influent rivers and/or by a stable supply of phosphorus from the anoxic layer (no formation of photosynthetic bacterial layer and small upwelling), but the appearance is inhibited by a high chloride ion concentration with large upwelling. The main reason for the formation of a photosynthetic bacterial layer from 1989 to May 1992 was that sunlight reached the top of the anoxic layer because of the increase in transparency due to inhibition of the Anabaena bloom with upwelling. The dense layer of photosynthetic bacteria blocked nutrient diffusion from the anoxic layer to the oxygenic layer by uptake, and decreased the biomass of phytoplankton in the oxygenic layer.

Background: Three-dimensional EUS (3D-EUS) technology has facilitated spatial interpretation of US images. However, acquisition of consecutive US scans is time consuming and difficult. A new 3D-EUS system was developed that negates this problem by allowing rapid image renewal and the efficient production of consecutive US scans. Methods: Three-dimensional images were reconstructed from a series of 2-dimensional images corresponding to the rotation angle of the echoendoscope as measured with an electromagnetic tracking system. To evaluate the technical feasibility of the system, 3-dimensional images of splenic veins in 2 patients and an esophageal submucosal tumor in a third patient were generated. Results: The 3D-EUS system acquired image data at a rate of 30 frames per second and allowed visualization of these data in real-time. The area of interest was clearly and rapidly portrayed in all 3 patients. Conclusion: This study demonstrates the efficiency of the new 3D-EUS system described in this report. Further development of this novel 3D-EUS system may lead to new applications of this technology.

Background: An understanding of the development of esophageal varices is important in the evaluation of risk of variceal hemorrhage. To clarify factors affecting the development of esophageal varices, the morphology and hemodynamics of the left gastric vein were analyzed with color Doppler EUS. Methods: Sixty-seven patients with esophageal varices underwent color Doppler EUS. Seventeen had small varices (F1), 32 had medium varices (F2), and 18 had large varices (F3). Results: Hepatofugal blood flow velocity in the left gastric vein trunk increased as the size of the varices increased (p < 0.0001), whereas the diameter did not increase. The left gastric vein bifurcates into anterior and posterior branches. As the size of the varices enlarged, the branch pattern was more likely to be anterior branch dominant (p = 0.041). There was no significant difference between the 3 size groups of esophageal varices with respect to the size of the paraesophageal collaterals. The detection rate and diameter of the perforating vein increased as the size of the varices increased (p = 0.032 and 0.012, respectively). Conclusion: Blood flow velocity in the left gastric vein trunk, branches, and perforating veins may regulate blood flow supplying the esophageal varices and contribute to their development. These findings are important to understanding the pathogenesis of esophageal varices. (Gastrointest Endosc 2002;55:512-7.)

BACKGROUND AND STUDY AIMS: The time to recurrence of esophageal varices may vary greatly between patients even after the same endoscopic therapy. To clarify the factors which contribute to recurrence after endoscopic treatment, the hemodynamics and morphology of the left gastric vein (LGV) were investigated using color Doppler endoscopic ultrasonography (EUS). PATIENTS AND METHODS: A total of 31 patients with high-risk esophageal varices underwent color Doppler-EUS before receiving endoscopic variceal ligation and endoscopic injection sclerotherapy combined therapy. Endoscopic examination was performed every 3 months after the treatment to evaluate recurrence of varices. RESULTS: A total of 18 patients responded to the therapy, while 13 patients did not respond, and had recurrence within 12 months. The hepatofugal flow velocity in the LGV trunk was significantly lower in the responders (9.9 vs. 13.9 cm/sec; P = 0.02). The branch pattern of the LGV was categorized into three groups: anterior branch dominant, posterior branch dominant, and no-dominant type. The incidence of the anterior branch dominant type was significantly less in responders (17 vs. 70 %; P = 0.01). There was no significant difference in the LGV trunk diameter and the size of the paraesophageal vein between the two groups. CONCLUSION: Risk factors for recurrence can be analyzed in detail using color Doppler-EUS. Further investigation using color Doppler-EUS may enable us to select the optimal way to treat esophageal varices to prevent recurrence.

Abstract: Background. We previously demonstrated that heparin-binding epidermal growth factor-like growth factor (HB-EGF) was expressed in rat mesangial cells and was involved in the progression of of glomerulonephritis in human and animal models. Soluble HB-EGF promotes cultured rat mesangial cell proliferation and the synthesis of type I and type III collagen mRNA. However, the precise role of proHB-EGF in mesangial cell function has not yet been clarified. In the present study, we address this question. Methods. ProHB-EGF-transfected rat mesangial cells (MsC; MsCproHB-EGF) and empty vector-transfected rat MsC (MsCvector) were constructed. Cells were cultured in fetal calf serum (FCS)-containing (10%) or FCS-deficient medium, and the growth rates and numbers of surviving cells were determined. To elucidate the anti-apoptotic effect of proHB-EGF, cells were exposed to hydrogen peroxide (H2O2) or dexamethasone (DEX). Apoptosis was identified by qualitative and quantitative analysis. Expression of Bcl-2 protein in MsCproHB-EGF after exposure to apoptosis inducers was also evaluated. Results. When cells were plated in a medium containing 10% FCS, the growth rate of MsCproHB-EGF was not different from that of MsC transfected with a plasmid alone (MsCvector). When cultured in the absence of FCS, MsCvector showed decreased cell numbers, indicating apoptotic cell death. In contrast, MsCproHB-EGF formed small colonies, although they did not show increased cell numbers, while cell viability was 90%–100% of the initial cell number after subculture. When quiescent MsC were exposed to DEX or H2O2, MsCvector exhibited significant DNA laddering, whereas MsCproHB-EGF showed resistance to these stimuli. The release of caspase-3 from MsCproHB-EGF after exposure to DEX or H2O2 was significantly lower than that from MsCvector. Bcl-2 protein expression was weak in MsCproHB-EGF at the baseline, but this expression was significantly upregulated after exposure to these stimuli. Confluent MsCproHB-EGF spontaneously expressed high level of p21 protein. Northern blot analysis revealed that MsCproHB-EGF expressed increased levels of type I and type III collagen mRNA and proteins compared with those of MsCvector. Conclusions. These results indicate that proHB-EGF contributes to mesangial cell survival by promoting cell viability and by inhibiting apoptosis. The anti-apoptotic effect of proHB-EGF could be closely related to the upregulation of Bcl-2 and p21 expression.

Abstract: The densities and growth rates of dominant phytoplankton in Lake Oshima-Ohnuma were determined during May to July 1996 to clarify the mechanism of change from spring-dominant to summer-dominant phytoplankton species, examining the influence of zooplankton grazing and nutrient limitation. The dominant phytoplankton in April and May were Asterionella gracillima and Nitzschia spp. Their growth rates were low in May and their densities fell thereafter. The bottle experiment suggests that the main reason for decreases in dominant species has been nutrient deficiency, and zooplankton (sized from 30 to 160 μm) have supported the growth of A. gracillima to recycle nutrients in May. The maximum growth rate was shown by Melosira (Aulacoseira) ambigua living at 2 m in May and June. Although the growth rate of the summer-dominant species Melosira (Aulacoseira) granulata was not as high as that of M. ambigua in May and June, the ambient density increased from late June. Survival in the lower zone of the unstratified euphotic layer might have contributed to the abundance of M. granulata, since the growth rate of this species was not so low as that of M. ambigua at 6 m in June and July. The bottle experiment suggests that the growth of M. granulata was also nutrient limited in June and July and that zooplankton grazing was partially responsible for repressing the biomass of M. granulata before it began growing rapidly in late June.

Brain intracellular platelet-activating factor acetylhydrolase (PAF-AH) isoform I is a member of a family of complex enzymes composed of mutually homologous alpha(1) and alpha(2) subunits, both of which account for catalytic activity, and the beta subunit. We previously demonstrated that the expression of one catalytic subunit, alpha(1), is developmentally regulated, resulting in a switching of the catalytic complex from alpha(1)/alpha(2) to alpha(2)/alpha(2) during brain development (Manya, H., Aoki, J., Watanabe, M., Adachi, T., Asou, H., Inoue, Y., Arai, H., and Inoue, K. (1998) J. Biol. Chem. 273, 18567-18572). In this study, we explored the biochemical differences in three possible catalytic dimers, alpha(1)/alpha(1), alpha(1)/alpha(2), and alpha(2)/alpha(2). The alpha(2)/alpha(2) homodimer exhibited different substrate specificity from the alpha(1)/alpha(1) homodimer and the alpha(1)/alpha(2) heterodimer, both of which showed similar substrate specificity. The alpha(2)/alpha(2) homodimer hydrolyzed PAF and 1-O-alkyl-2-acetyl-sn-glycero-3-phosphorylethanolamine (AAGPE) most efficiently among 1-O-alkyl-2-acetyl-phospholipids. In contrast, both alpha(1)/alpha(1) and alpha(1)/alpha(2) hydrolyzed 1-O-alkyl-2-acetyl-sn-glycero-3-phosphoric acid more efficiently than PAF. AAGPE was the poorest substrate for these enzymes. The beta subunit bound to all three catalytic dimers but modulated the enzyme activity in a catalytic dimer composition-dependent manner. The beta subunit strongly accelerated the enzyme activity of the alpha(2)/alpha(2) homodimer but rather suppressed the activity of the alpha(1)/alpha(1) homodimer and had little effect on that of the alpha(1)/alpha(2) heterodimer. The (His(149) to Arg) mutant beta, which has been recently identified in isolated lissencephaly sequence patients, lost the ability to either associate with the catalytic complexes or modulate their enzyme activity. The enzyme activity of PAF-AH isoform I may be regulated in multiple ways by switching the composition of the catalytic subunit and by manipulating the beta subunit.

A new unstable hemoglobin was found in a 33-year-old Japanese woman with a history of chronic, partially compensated hemolytic anemia. An electrophoretically silent unstable β chain was prepared by PCMB precipitation and the amino acid substitution determined as β31(B13)Leu → Pro. Her son was a carrier of the same variant, who manifested milder symptoms.

Because of its potential for chronic nephrotoxicity, the long-term use of cyclosporine A (CsA) as treatment for nephrotic syndrome (NS) is controversial. The clinical outcome of patients with NS treated with CsA is unclear. We retrospectively evaluated 35 children with idiopathic NS, 24 with steroid-dependent NS (SDNS), and 11 with steroid- resistant NS (SRNS), who received CsA therapy for more than 12 months (median, 23 months) at the dosage maintaining 50 to 120 ng/mL in trough level. For SDNS patients, CsA was added to prednisolone after complete remission was achieved. For SRNS patients, CsA was used in combination with alternate-day prednisolone. Initial renal histology showed minimal changes (MC) in 28 patients (including all of the patients with SDNS) and focal segmental glomerulosclerosis (FSGS) in seven patients. The patients were followed up for 2 to 10.5 years (median, 6.5 years) after the termination of the CsA therapy. In SDNS patients, the relapse rate, dosage of prednisolone, standard deviation score for height, and body mass index significantly improved during CsA treatment. The follow-up study showed the proportion of SDNS decreased to 13 of 24 (54%) patients. In SRNS patients, CsA therapy induced remission in 8 of 11 patients (73%) (complete remission in seven and incomplete remission in one). Six of 11 patients (55%) then became steroid sensitive. Post- therapy biopsies, performed in 13 patients (10 with SDNS and three with SRNS), showed mild stripped interstitial fibrosis in two SDNS patients (15%). Long-term CsA therapy in moderate doses was effective to the patients with SDNS and SRNS and low in incidence of nephrotoxicity. The long-term use of CsA appears to result in a decrease in the proportion of SDNS and acquisition of subsequent steroid responsiveness in SRNS. (Am J Kidney Dis 1998 Jun;31(6):932-9)

Ultraviolet and C 1s and N 1s X-ray photoelectron spectra of a ferromagnetic charge-transfer complex, TDAE−C60, where TDAE is tetrakis(dimethylamino)ethylene, have been measured. The appearance of a new peak above the highest occupied band of C60 at 1.2 eV below the Fermi level with a peak onset of 0.5 eV indicates that an electron is transferred from TDAE to C60 and that TDAE−C60 is not metallic but semiconductive. The N 1s core spectrum of the complex shows a wide band consisting of two components, and the intensity of the higher binding energy one decreases under X-ray irradiation. The observed components could be ascribed to nitrogen atoms in TDAE⁰ and TDAE²⁺ on the basis of the electrostatic potential model in combination with the CNDO/2 molecular orbital calculation. Possible appearance of the charge density wave state along the TDAE chain in the c-direction of TDAE−C60 crystal has been suggested.

Cell lines transformed by woolly monkey sarcoma virus (WSV) in the absence of infectious virus production were analyzed for the expression of woolly monkey helper viral p30, p12, and gp70 antigens. Several lines produced high levels of both p30 and p12, whereas gp70 was not detectable. One transformed clone expressed only p12, and in another cell line, none of the helper viral antigens were detected. The properties of each sarcoma virus bred true upon transmission, indicating that each variant represents a distinct genotype. The different cell lines were examined with respect to properties characteristic of the transformed state. The in vitro growth properties and oncogenicity of each WSV-transformed clone were indistinguishable, indicating that transformation by WSV occurs independently of the expression of at least three helper viral polypeptides.

The immunological responses of inbred mice to structural components of one class of endogenous virus were investigated by means of radioimmunoassays utilizing highly purified viral proteins. Naturally occurring antiviral antibodies were demonstrated only in those strains possessing information for induction of a mouse cell-tropic endogenous virus. Moreover, these antibodies invariably appeared subsequent to the detection of spontaneous replication of this virus in the same animal. The immune responses elicited were much stronger against endogenous viral gp70 than p30, consistent with previous findings of tolerance in the mouse to the major structural antigen of its endogenous virus. However, the demonstration of an immune response to p30 under conditions of both natural and experimental immunization establishes that tolerance to this viral antigen can be overcome.

We analyzed retrospectively a relative risk of measles attacks in vaccinated vs. unvaccinated students using two independent outbreaks in Japan. The first involved 33/328 (10%) students where 64% students and 30% measles cases had been vaccinated. The second involved 27/241 (11%) students where 81% students and 48% measles cases had been vaccinated. The attack rates of vaccinated vs. unvaccinated students were significantly low (p<0.001), but they accounted 25% in both episodes. The statistically significant clinical features among vaccinated and unvaccinated cases included the average duration of fever, 5.16±1.71 vs. 6.67±2.19 days (p=0.01) and the incidence of complications, 0 vs. 25%, respectively. These results suggested that the measles in vaccinated cases were mostly due to secondary failures.

An attempt to prevent irradiation-induced thymic lymphomas in C57BL mice was made by inducing active immunity to endogenous type-C virus with inactivated Rauscher murine leukemia virus (MuLV) or inactivated Gross MuLV or by transferring passive immunity to endogenous type-C virus with goat anti-Gross MuLV IgG. Control groups received the following immunogen or treatment: inactivated simian sarcoma virus, complete Freund's adjuvant, normal goat IgG, and diluent, in both irradiated and nonirradiated C57BL mice Active immunity to the 70,000 molecular weight glycoprotein AKR-gp70 by immunization with Rauscher MuLV and passive immunity to AKR-gp70 by passive transfer of goat anti-Gross-MuLV IgG was measurable throughout some of the latent period of tumor development; in these two groups a significant reduction in tumor incidence was observed, as compared to the other experimental and control groups. Thus, the present findings support the concept of a type-C virus etiology of irradiation-induced leukemias and demonstrate the applicability of immunologic techniques directed against the endogenous type-C virus in the prevention of this disease.

This study examined the relationship between exercise-induced changes in the concentration of circulating immunocompetent cells and their surface expression of adhesion molecules: L-selectin (CD62L) and threeß2-integrins [LFA-1(CD11a/CD18), Mac-1 (CD11b/CD18), and p150/95(CD11c/CD18)]. Eight young male volunteers exercised on a cycle ergometer for 60 min at 60% maximal oxygen uptake. Peripheral blood samples, collected every 30 min throughout exercise and during the 2-h recovery period, were used for flow-cytometric analysis. The experimental results were compared with control data obtained ever 60 min at corresponding times of the nonexercise day. The exercise regimen induced a granulocytosis and a lymphocytosis, mainly due to an elevation of CD8+ and CD16+ cells. During recovery, a further granulocytosis occurred but accompanied by a lymphopenia. The increased CD8+ cell-count during exercise was characterized by a selective mobilization of the CD62L- and CD11ahigh cells, i.e.primed CD8+ cells. A postexercise suppression of CD4+ cell-count was derived only from CD62L+ cells. The CD11b+ and CD11c+ lymphocytes also increased during exercise, largely attributable to an increase in CD16+ cells which co-expressed CD11b and CD11c molecules. The CD62L surface density of granulocytes increased significantly during recovery. This resulted from a selective influx of CD62Lhigh granulocytes into the circulation. There were no significant changes in per-cell density of the threeß2-integrins on granulocytes and lymphocytes throughout the experimental period. These results suggest that the cell-surface expression of CD62L (and CD I la) molecules is associated with the differential mobilization of CD8+ cells during exercise, the postexercise suppression of CD4- cell-counts and the granulocytosis following exercise.

Genetic information coding for type C RNA viruses is transmitted within the DNA of mouse cells. At least three endogenous viruses have so far been immunologically distinguished by radioimmunoassays for their 12,000-molecular-weight polypeptides (p12). In the present study, the 70,000-molecular-weight glycoproteins (gp70) of three prototype viruses were purified, and competition radioimmunoassays were developed for each. By use of these immunoassays, the antigenic determinants of gp70's of different classes of endogenous virus, isolated from the same and from a variety of other mouse strains, were readily discriminated. In contrast, viruses of the same class were indistinguishable. These findings further document the existence of three distinct endogenous viruses of mouse cell. The levels of type C viral gp70 were quantitated in tissues and sera of several inbred strains. The pattern of immunological reactivity of the gp70 detected in serum was indistinguishable from that of the viral gp70 partially purified from tissues of the same strain. Moreover, in each case it was indistinguishable from that of a specific class of endogenous virus. In virus-negative tissues of BALB/c and NIH Swiss mice, the viral gp70 detected was shown to be representative of a class III endogenous virus whose p12 polypeptide was also expressed by the same cells.

The humoral antibody response of feline leukemia virus (FeLV)-exposed cats to the feline oncornavirus-associated tumor cell-membrane antigen (FOCMA) is directly correlated with immunosurveillance against tumor development under natural conditions. By means of membrane immunofluorescence and radioimmunoprecipitation, the antibody response to FOCMA was found to be independent of the antibody response to the major envelope and core proteins of FeLV, gp70 and p30. This was especially true for healthy viremic cats, where antigenemia with circulating FeLV gp70 and p30 apparently binds any free antibody to these proteins, but high levels of FOCMA antibody are often concurrently present. Exhaustive in vitro absorption of highly immune nonviremic serum with gp70 and p30 also failed to remove FOCMA antibody activity. These results indicate that FOCMA is not one of these major FeLV structural proteins.

Morganella morganii produced CO when cultured in a medium containing casamino acids or peptone as the sole carbon source. Although the production of CO was distinctly enhanced by the addition of hemin to the medium, the amounts of CO produced in the absence of hemin were nearly proportional to the amounts of peptone added to the culture media. Examination of 20 amino acids for their ability to produce CO by resting cells revealed that phenylalanine, tyrosine, histidine and tryptophan were the sources of CO. Oxygen and hemin were necessary for CO production from the amino acids except tryptophan which produced CO in the absence of hemin. When cells were incubated for 4 h at 30° C in the mixture containing 40 µmol tyrosine and 1 µmol hemin, about 15 µmol CO was produced; the activity of CO production was about 1.2 µmol CO/h · mg cell nitrogen. Phenylpyruvic acid, p-hydroxyphenylpyruvic acid and imidazolepyruvic acid also produced CO in the presence of hemin, while indolepyruvic acid produced CO regardless of the presence or absence of hemin. The production of CO by the 2-oxo acids proceeded spontaneously and did not require the presence of M. morganii cells.

A reverse transcriptase-containing virus has recently been isolated from a squirrel monkey (Saimiri sciureus). Molecular hybridization studies demonstrate that the squirrel monkey retrovirus (SMRV) is endogenous to this New World primate, yet lacks detectable nucleotide sequence homology with cellular DNAs of representative Old World primates or with the genomes of previously isolated Old World primate retroviruses. The 35,000-dalton major structural protein (p35) of SMRV was purified and shown to possess antigenic determinants distinct from those of known retroviruses. While SMRV was found to lack antigenic determinants broadly shared among mammalian type-C viruses, immunologic crossreactivity was demonstrated between SMRV p35 and the major structural protein (p26) of Mason-Pfizer monkey virus, a prototype type-D retrovirus of Old World monkeys. These findings support the concept that SMRV and Mason-Pfizer monkey virus are evolutionarily related, and raise the possibility that a progenitor of type-D retroviruses became genetically associated with primates at a very early time in their evolution.

A strategy based on the identification of type-specific antigenic determinants in the transitional products of gag (p15, p12, and p30 proteins), pol (reverse transcriptase), and env (gp70 glycoproteins) genes of mammalian type C viruses has been used to study genetic recombination between these RNA viruses. By this approach, recombinants involving exogenous and endogenous mouse type C viruses have been identified and genetically mapped. Analogous techniques have been applied to investigate the genetic relationships between different classes of endogenous virus that exist within the same mouse cells. Proteins of the inducible class of xenotropic virus were shown to exhibit extensive antigenic homology with the gag but not the env gene products of the ecotropic virus class. Instead, the env gene-coded glycoproteins of the inducible and noninducible xenotropic virus classes possessed striking antigenic relatedness. These results, as well as supporting findings from molecular hybridization, favor the concept that the inducible xenotropic virus of mouse cells arose by a recombinational mechanism involving the progenitors of the other two endogenous virus classes.

We undertook the present study to clarify the molecular mechanism of the effect of a new anti-cancer drug, vesnarinone, on a human salivary gland cancer cell line, TYS. We isolated TSC-22cDNA as avesnarinone-inducible gene from a cDNA library constructed from vesnarinone-treated TYS cells. TSC-22 was originally reported as a transforming growth factor (TGF)-beta-inducible gene. The expression of TSC-22 was up-regulated within a few hours after treatment with vesnarinone and was continued for 3 days. The level of TSC-22 mRNA in TYS cells was continuously increased until the cells reached confluency. Furthermore, the induction of TSC-22 by vesnarinone was inhibited by treatment with cycloheximide. When we treated the cells with an antisense oligonucleotide against TSC-22 mRNA under quiescent conditions, the antisense oligonucleotide stimulated the growth of TYS cells; however, under growing conditions the antisense oligonucleotide did not affect cell growth. Furthermore, the antisense oligonucleotide suppressed the antiproliferative effect of vesnarinone. These results suggest that TSC-22 may be a negative growth regulator and may play an important role in the antiproliferative effect of vesnarinone.

The synthesis and characterization of the first stable example of a substituted lead analogue of methylmethylene, a valence isomer of ethylene, are reported. The title compound features a bond between a divalent and a tetravalent lead center and is stabilized by the incorporation of the lead−lead bond into a stabilizing ring structure. It was synthesized fortuitously and in low yield by the “activation” of the diplumbyne [PbAr^Trip2]2, where Ar^Trip2 = −C6H3−2,6-(C6H2-2,4,6-ⁱPr3)2, with trimethylsilyl azide, N3SiMe3, and it was characterized via NMR spectroscopy and by single-crystal X-ray crystallography.

BACKGROUND AND STUDY AIMS: Endoscopic variceal ligation (EVL) is an alternative to sclerotherapy for the treatment of esophageal varices, but is associated with higher rates of recurrence and subsequent bleeding than sclerotherapy. To prevent recurrence of varices after EVL, we have developed a low-dose diode laser therapy combined with the injection of indocyanine green, which allows enhanced tissue absorption of the laser beam selectively around varices. In this study we investigated the efficacy and safety of this technique. PATIENTS AND METHODS: Eight patients with F2 or F3 esophageal varices were enrolled. At 1 week after EVL, indocyanine green solution (1 mg/ml) was injected submucosally around the remaining varices. A diode laser (power 10 watts) was applied to the surface from the esophagogastric junction to 5 cm above it. The spot size was kept to 5 mm in diameter. RESULTS: Laser irradiation was performed safely, without bleeding from the varices, or perforation. There were no major complications. Endoscopy 1month later showed F0 forms in seven patients, F1 in one patient, and no red color sign in any patient. No recurrence of varices has been observed in any of the patients during the follow-up period of at least 12 months. CONCLUSION: This technique may provide a simple, safe and effective procedure, as an additional treatment to EVL, for the prevention of recurrence of esophageal varices.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.