AM-3K, a novel monoclonal antibody specific for tissue macrophages and its application to pathological investigation

An anti-human macrophage monoclonal antibody, AM-3K, was produced using human alveolar macrophages as antigen. The molecular weights of the antigen recognized by AM-3K were 120 and 70 kD. Immunohistochemically, AM-3K reacted intensely with most macrophages in lymphoreticular organs and in many other organs and tissues. In the spleen, AM-3K reacted with red pulp macrophages, some white pulp macrophages, and tingible body macrophages in lymphoid follicles. In the lymph nodes, many macrophages distributed in the outer cortex, paracortical area, medulla, capsule, or within lymphoid follicles showed an intense reaction for AM-3K. Kupffer cells of the liver, macrophages in the connective tissues, and interstitial macrophages of the kidneys, pancreas, testis, and many other organs were also strongly labelled. AM-3K also reacted with macrophages in many pathological conditions. This antibody, however, did not react with dendritic cell populations, such as epidermal Langerhans cells, interdigitating cells in the paracortex of the lymph nodes, and follicular dendritic cells within the lymphoid follicles, nor with cells other than macrophages, including epithelial cells, vascular endothelial cells, lymphocytes, and granulocytes. Reaction products for AM-3K were found on the cytoplasmic membrane of macrophages by immunoelectron microscopy. In both cryostat sections and formalin-fixed paraffin sections, this monoclonal antibody recognized the antigen present on the cell surface membrane of tissue macrophages, but not monocytes or dendritic cells.

Squamotacin: an annonaceous acetogenin with cytotoxic selectivity for the human prostate tumor cell line (PC-3)

The bark extracts of Annona squamosa yielded a new bioactive acetogenin, squamotacin (1), and the known compound, molvizarin (2), which is new to this species. Compound 1 is identical to the potent acetogenin, bullatacin (3), except that the adjacent bistetrahydrofuran (THF) rings and their flanking hydroxyls are shifted two carbons toward the gamma-lactone ring. Compound 1 showed cytotoxic selectively for the human prostate tumor cell line (PC-3), with a potency of over 100 million times that of Adriamycin.

Five novel mono-tetrahydrofuran ring acetogenins from the seeds of Annona muricata

Bioactivity-directed fractionation of the seeds of Annona muricata L. (Annonaceae) resulted in the isolation of five new compounds: cis-annonacin (1), cis-annonacin-10-one (2), cis-goniothalamicin (3), arianacin (4), and javoricin (5). Three of these (1-3) are among the first cis mono-tetrahydrofuran ring acetogenins to be reported. NMR analyses of published model synthetic compounds, prepared cyclized formal acetals, and prepared Mosher ester derivatives permitted the determinations of absolute stereochemistries. Bioassays of the pure compounds, in the brine shrimp test, for the inhibition of crown gall tumors, and in a panel of human solid tumor cell lines for cytotoxicity, evaluated relative potencies. Compound 1 was selectively cytotoxic to colon adenocarcinoma cells (HT-29) in which it was 10,000 times the potency of adriamycin.

The absolute configuration of adjacent bis-THF acetogenins and asiminocin, a novel highly potent asimicin isomer from Asimina triloba

A novel acetogenin, asiminocin (1), was isolated by activity-directed fractionation from the stem bark of the paw paw tree, Asimina triloba. By spectral and chemical methods, 1 was identified as (30S)-hydroxy-4-deoxyasimicin. The absolute configuration of 1, along with those of previously reported acetogenins asimin, asiminacin, bullatin, (30S)-bullanin, and (30R) bullanin, was determined by Mosher ester methodology. Compound 1 was highly inhibitory to three human solid tumor cell lines with over a billion times the potency of adriamycin.

Seasonal change in the exacerbations of Crohn's disease

BACKGROUND

Ulcerative colitis (UC) has been reported to run a clinical course with seasonal exacerbations in both retrospective and prospective studies; such a seasonality was not been observed, however, in Crohn's disease (CD).

METHODS

The monthly distribution in the relapse of CD was retrospectively studied to ascertain whether there is any seasonal variation in the exacerbations of the disease. During the period of 1972 to 1993, 139 patients who had been regularly followed up for at least 13 consecutive months were analyzed.

RESULTS

In a total of 10,693 follow-up months for these patients 592 relapses occurred in the study period. The highest relapse rate was found in the autumn and winter, whereas the lowest was in the summer.

CONCLUSION

This study shows that CD runs a clinical course with seasonal exacerbations, suggesting that seasonal or exogenous factors may be involved in the relapse of CD.

[The effect of interferon in combination with ribavirin on the plus and minus strands of hepatitis C virus RNA in patients with hepatitis]

The effect of interferon in combination with ribavirin on the plus and minus strands of hepatitis C virus (HCV) RNA in patients with chronic hepatitis C (CHC) was studied by means of nested RT-PCR. The results showed that in those who respond to the combination of antiviral therapy, their increased serum ALT levels decreased to normal range, but more than half (55.56%) of these patients relapsed 24 weeks after cessation of the antiviral therapy. The positive rate of the plus strand HCV RNA in serum (92.31%) decreased significantly to 38.46% (P < 0.005) and that of the minus strands HCV RNA in peripheral blood mononuclear cells (PBMC, 76.92%) to 38.46% (P < 0.05) at the end of the treatment, but little effect on the plus strand HCV RNA in PBMC in these patients was found. Relapse occurred in patients whose plus and minus strands of HCV RNA in PBMC remained positive during treatment. These data indicated that absence of HCV RNA in serum do not mean complete clearance of HCV and can not predict a sustained therapeutic response. For evaluating the antiviral effect and prognosis it is essential to measure the plus and minus strands of HCV RNA in serum and PBMC simultaneously. The results of the combined antiviral therapy were similar to that of single interferon treatment; it seems that rib-a-virin do not enhance the antiviral effect of interferon.

Insulin and vasopressin elicit inhibition of cholera-toxin-stimulated adenylate cyclase activity in both hepatocytes and the P9 immortalized hepatocyte cell line through an action involving protein kinase C

Incubation of hepatocytes or the SV40-DNA-immortalized hepatocyte P9 cell line with cholera toxin led to a time-dependent activation of adenylate cyclase activity, which occurred after a defined lag period. When added together with cholera toxin, each of the hormones insulin and vasopressin was capable of attenuating the maximum stimulatory effect achieved by cholera toxin over a period of 60 min through a process which could be blocked by the compounds staurosporine and chelerythrine. Attenuating effects on cholera-toxin-stimulated adenylate cyclase activity could also be elicited by using either the protein kinase C (PKC)-stimulating phorbol ester PMA (phorbol 12-myristate 13-acetate) or the protein phosphatase inhibitor okadaic acid. Alkaline phosphatase treatment of membranes reversed the inhibitory effect of PMA. Cholera toxin also stimulated the adenylate cyclase activity of intact CHO (Chinese-hamster ovary) and NIH-3T3 cells, but this activity was insensitive to the addition of PMA. Overexpression of various PKC isoforms in CHO cell lines did not confer sensitivity to inhibition by PMA upon cholera-toxin-stimulated adenylate cyclase activity. Rather, overexpression of the gamma isoform of PKC allowed PMA to stimulate adenylate cyclase activity in CHO cells. It is suggested that the PKC-mediated phosphorylation of a membrane protein attenuates cholera-toxin-stimulated adenylate cyclase activity in hepatocytes and P9 cells. The cellular selectivity of such an action may be due to the target for this inhibitory action of PKC being a particular isoform of adenylate cyclase which provides the major activity in hepatocytes and P9 cells, but not in either CHO or NIH-3T3 cells.

Independent down-regulation of EP2 and EP3 subtypes of the prostaglandin E2 receptors on U937 human monocytic cells

Co-expression of EP2 and EP3 subtypes of prostaglandin E2 (PGE2) receptors (R) by U937 human monocytic cells permitted comparative studies of desensitization of each subtype. Specific binding of [3H]PGE2 to membranes of U937 cells showed a Kd of 2.9 +/- 0.3 nM (mean +/- SEM) and a Bmax of 40.5 +/- 1.0 fmol/mg protein, and was competitively inhibited by PGE2 > or = PGE1 > PGF2 alpha > PGD2 > PGI2. EP2 R and EP3 R mRNA were detected by reverse transcription-polymerase chain reaction and Northern blots. EP3 R expression was demonstrated by inhibition of [3H]PGE2 binding with the EP1/EP3 agonist sulprostone [50% inhibitory concentration (IC50 = 3.3 +/- 0.6 nM)] and the EP3/EP2 agonist M&B 28767 (IC50 = 2.1 +/- 0.3 nM), but not with the EP1 antagonist SC-19220. EP2 R protein was identified by Western blot analysis using specific rabbit IgG antibodies to an amino-terminal peptide of the EP2 R. EP2 R transduced PGE2 stimulation of significant increases in cellular [cAMP]i [50% effective concentration (EC50 = 20 +/- 2.5 nM)], and EP3 R mediated sulprostone inhibition of forskolin elevation of [cAMP]i (IC50 = 1.3 +/- 0.4 nM). Pretreatment of U937 cells with phorbol 12-myristate 13-acetate (PMA), which activates protein kinase C (PKC), for 1 hr reduced the total number, but not the affinity, of PGE2 R by down-regulating principally EP2 R. In contrast, a 24-hr exposure to PMA, which is known to down-regulate PKC, suppressed both the total number and affinity of PGE2 R on U937 cells with concurrent reductions in EP2 R and EP3 R. The down-regulation of EP2 R by PMA at 1 hr was blocked by staurosporine, an inhibitor of PKC, whereas the down-regulation of EP3 R by PMA at 24 hr was blocked by indomethacin. Pretreatment of U937 cells with PGE2 for 1 and 24 hr reduced both the binding affinity and the total number of PGE2 R, by co-ordinate suppression of the EP2 R and EP3 R. Desensitization of EP2 R and EP3 R for 1 hr with PGE2 suppressed subsequent PGE2-evoked chemokinetic responses to PGE2, whereas selective down-regulation of EP2 R alone by PMA for 1 hr had no effects on U937 cell migration. Thus expression of each subtype of PGE2 R is regulated independently and EP3 R, but not EP2 R, transduces PGE2 effects on migration of mononuclear phagocytes.

Stimulation of matrix metalloproteinase-dependent migration of T cells by eicosanoids

Prostaglandin E2 (PGE2) and leukotriene B4 (LTB4), at nanomolar to micromolar concentrations, elicited migration of human blood T cells and cultured T lymphoblastoma cells of the Tsup-1 line through a layer of Matrigel basement membrane matrix. The density of Tsup-1 cell high-affinity receptors was low for PGE2 and high for LTB4, resulting in respectively predominant chemokinetic and chemotactic stimulation of migration. Migration-enhancing concentrations of PGE2 and LTB4 also increased Tsup-1 cell content and secretion of matrix metalloproteinases (MMPs) 2, 3, and 9, which were quantified by Western blots and zymography, and augmented Tsup-1 cell-surface expression of the MMPs, as shown by flow cytometry. That a specific MMP inhibitor suppressed migration of blood T cells and Tsup-1 cells through Matrigel, but did not affect PGE2- and LTB4-initiated T cell migration through micropore filters without Matrigel, suggests dual requirements for MMP expression and enhanced motility in T cell passage through basement membranes.

Human malignant mesothelial cells: variability of ultrastructural features in established and nude mice transplanted cell lines

The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity.

Asimilobin and cis- and trans-murisolinones, novel bioactive Annonaceous acetogenins from the seeds of Asimina triloba

Three new bioactive Annonaceous acetogenins, asimilobin [1], cis-murisolinone [2], and trans-murisolinone [3], have been isolated from an ethanolic extract of the seeds of Asimina triloba by directing the fractionation with brine shrimp lethality. The structure were elucidated based on spectroscopic and chemical methods, In addition, cis- and trans-bullatacinone, which are known compounds, were obtained. Asimilobin [1] has adjacent bis-THF rings, located at C-10 to C-17 and having only one flanking hydroxyl group at C-18. Compounds 1-3 showed cytotoxicity values comparable with adriamycin against six human solid tumor cell lines.

Resistance to transformation by insertionally activated c-erbB is a dominant phenotype in fibroblasts

Tissue-specific factors influence whether cells are susceptible to transformation by erbB oncogenes. Avian fibroblasts resist transformation by insertionally activated c-erbB (IAc-erbB), whereas erythroblasts are transformed by this mutant of the epidermal growth factor receptor. In studies presented here, NIH/3T3 cells resisted transformation by IAc-erbB. This finding indicates that the nonpermissiveness of fibroblasts is conserved between avian and murine species. Surprisingly, expression of IAc-erbB blocked transformation by a v-erbB allele. The trans-dominant interference by IAc-erbB occurred despite expression at levels lower than for v-erbB. Together with previous reports, the results indicate that IAc-erbB can exert opposite growth effects in different tissues. The switch from positive to negative growth regulation, which depends on the cellular context, provides novel insight into tissue-specific regulation of receptor tyrosine kinases. Evasion of cell-specific inhibition apparently contributes to the distinct tissue tropisms of various erbB mutants.

New bioactive adjacent bis-THF annonaceous acetogenins from Annona bullata

Five new adjacent bis-THF annonaceous acetogenins, 32-hydroxybullatacin, 31-hydroxybullatacin, 30-hydroxybullatacin, and (2,4-cis and trans)-28-hydroxybullatacinones, were isolated from the ethanolic extract of the bark of Annona bullata Rich. (Annonaceae). The absolute configurations of the above five compounds, as well as those of (2,4-cis and trans)-32-, 31-, and 30-hydroxybullatacinones and (2,4-cis and trans)-bulladecinones, previously isolated from the same extract, were defined by the application of the advanced Mosher ester [methoxy(trifluoromethyl)phenyl acetate or MTPA] methodology. The determination of the absolute configuration of C-20 of (2,4-cis and trans)-bulladecinones to be S supports our hypothesis that the cyclization of the THF rings of (2,4-cis and trans)-bulladecinones starts from C-12 (the right side). The first five compounds listed above showed potent bioactivities in the brine shrimp lethality test (BST) and among six human solid tumour cell lines.

Additional bioactive acetogenins, annomutacin and (2,4-trans and cis)-10R-annonacin-A-ones, from the leaves of Annona muricata

In a continuation of our research on bioactive components from the leaves of Annona muricata, three novel monotetrahydrofuran Annonaceous acetogenins, namely, annomutacin [1], (2,4-trans)-10R-annonacin-A-one [2], and (2,4-cis)-10R- annonacin-A-one [3], have been identified. Their structures were deduced by ms, nmr, ir, and uv spectral and chemical methods, and the absolute configurations were determined by Mosher ester methodology. A known bioactive amide, N-p-coumaroyl tyramine, was also found. Compound 1 and the mixture of compounds 2 and 3 showed selective cytotoxicities against the human A-549 lung tumor cell line.

[Isolation and identification of extrem thermophilic bacteria from hot springs of Sichuan and Tibet]

Eleven strains of extrem thermophilic bacteria belonging to the Bacillus Stearothermophiles were isolated from the hot springs of Sichuan and Tibet. The cells were gram-positive, sporulating and motile. The optimum temperature for growth was between 65 degrees C to 70 degrees C; the maximum 94 degrees C, and minimum 40 degrees C. The colour of colony was yellow to bright orange. The G+C content of the DNA in strains has been found to be in the range 48.4-53.15 mol%.

Longicin and goniothalamicinone: novel bioactive monotetrahydrofuran acetogenins from Asimina longifolia

Longicin [1] and (2,4-cis and trans)-goniothalamicinone [2], two new monotetrahydrofuran Annonaceous acetogenins, have been isolated from the leaves and twigs of Asimina longifolia (the long leaf paw paw) by the use of the brine shrimp lethality test for bioactivity-directed fractionation. The structures were elucidated based on spectroscopic and chemical methods. Compound 1 was converted to its ketolactone isomer, (2,4-cis and trans)-longicinone [3], to aid the stereochemical elucidation of 1. Compounds 1-3 showed selective and potent cytotoxicities to certain human tumor cell lines, with the potency of 1 against pancreatic carcinoma (PaCa-2) over one million times that of adriamycin. Nine known cytotoxic acetogenins, annonacin, xylomaticin, isoannonacin, gigantetrocins A and B, muricatetrocins A and B, gigantetrocin-A-one and goniothalamicin, were also isolated for the first time from this species.

Phenotypic and molecular analysis of a transgenic insertional allele of the mouse Fused locus

Spontaneous mutations at the mouse Fused (Fu) locus cause dominant skeletal and neurological defects and recessive lethal embryonic defects including neuroectodermal abnormalities and axial duplications. Here, we describe a new allele at the Fu locus caused by a transgenic insertional mutation, H epsilon 46. Embryos homozygous for the H epsilon 46 insertion die at day 9-10 post coitum and display phenotypic defects similar to those associated with Fu alleles. The H epsilon 46 locus was cloned and shown to contain a 20-kb deletion at the site of transgene insertion with no other detectable rearrangements. Genomic probes from the H epsilon 46 locus were mapped to a genetic locus closely linked to Fu on chromosome 17 and were hybridized to a YAC contig covering the FuKi critical region. Compound heterozygotes between H epsilon 46 and FuKi were inviable and displayed abnormalities at the same stage of embryogenesis as do homozygotes for either of the two mutations, demonstrating that these two recessive lethal mutations belong to the same complementation group. A genomic probe from the wild-type H epsilon 46 locus detected a transcript that is disrupted by the transgenic insertion, representing a candidate for the wild-type allele of Fused.

Fibrin sealant matrix supports outgrowth of peripheral sensory axons

It has been suggested that fibrin-based matrix has an important role during the early stage of nerve regeneration. A fibrin sealant matrix, which was made by combining diluted human fibrinogen and thrombin, was used as a substrate for in vitro elongation of neurites and in vivo regeneration of axons. In the in vitro experiment, dissociated embryonic chick sensory neurons were cultured on dishes coated with fibrin sealant matrix and compared with the solution of thrombin/calcium chloride, or with poly-D-lysine (PDLctr). After 16 hours, cultures were stained immunohistochemically with a monoclonal antineurofilament antibody. The neurons survived well, and an abundant network of neurites, qualitatively similar to that on PDLctr, developed on the fibrin sealant matrix. The percentage of neurons that had outsprout at 16 hours was the same both in the fibrin sealant matrix and PDLctr groups. By contrast, all the neurons plated on the dishes treated with the solution of thrombin/calcium chloride were dead after 16 hours. Immunohistochemical staining of fibrinogen also showed an even distribution of fibrin matrix over the culture dishes. For the in vivo experiments, 48 rat sciatic nerves were cut and reconnected with two epineurial stitches. Fibrin sealant matrix or phosphate buffer solution was applied to the transsected and repaired region. Pinch reflex test showed that the regeneration of the leading sensory fibre was significantly faster in the fibrin sealant matrix group than in the control group at 3 and 4 days. These results indicate that fibrin sealant matrix accelerates regeneration of axons in vivo during the early phase, and also supports elongation of neurites in vitro.

New bioactive monotetrahydrofuran Annonaceous acetogenins, annomuricin C and muricatocin C, from the leaves of Annona muricata

The leaves of Annona muricata have yielded two additional monotetrahydrofuran Annonaceous acetogenins, annomuricin C [1] and muricatocin C [2]. Compounds 1 and 2 each possess five hydroxyl groups; two hydroxyl groups are at the C-10/C-11 and C-10/C-12 positions in 1 and 2, respectively. The absolute configurations of 1 and 2, except for positions C-10 and C-11 or C-12, were determined by Mosher ester methodology. The C-10/C-11 and C-10/C-12 acetonides (1c, 2c) suggested relative stereochemistry and significantly enhanced the cytotoxicities against the A-549 human lung and the MCF-7 human beast solid tumor cell lines. One known monotetrahydrofuran acetogenin, gigantetronenin, not described previously from this plant, was also found.

Two new cytotoxic monotetrahydrofuran Annonaceous acetogenins, annomuricins A and B, from the leaves of Annona muricata

The leaves of Annona muricata have yielded eight monotetrahydrofuran Annonaceous acetogenins. Two of them, annomuricins A [1] and B [2], whose chemical structures were deduced by ms, nmr, ir, and uv spectral and chemical methods, are novel and unusual. Compounds 1 and 2 each possess five hydroxyl groups; two hydroxyl groups are vicinal, with the vicinal group of 1 threo and that of 2 erythro. The absolute configurations of 1 and 2 were determined by Mosher ester methodology. Six monotetrahydrofuran acetogenins, previously described in the seeds, were found in the leaves; these are gigantetrocin A, annonacin-10-one, muricatetrocins A and B, annonacin, and goniothalamicin.

Muricatocins A and B, two new bioactive monotetrahydrofuran Annonaceous acetogenins from the leaves of Annona muricata

The leaves of Annona muricata have yielded the novel monotetrahydrofuran Annonaceous acetogenins, muricatocins A [1] and B [2]. Each compound possesses five hydroxyl groups, with two hydroxyl groups at the C-10 and C-12 positions. The absolute configurations of 1 and 2 (except for positions C-10 and C-12) were determined by Mosher ester methodology. The C-10, C-12 acetonides (1c, 2c) suggested relative stereochemistry and significantly enhanced cytotoxicity against the A-549 human lung tumor cell line. Three known monotetrahydrofuran acetogenins, annonacin A, (2,4-trans)-isoannonacin, and (2,4-cis)-isoannonacin, were also found.

Molecular characterization of the 3' terminus of the simian hemorrhagic fever virus genome

The 3' end of the simian hemorrhagic fever virus (SHFV) single-stranded RNA genome was cloned and sequenced. Adjacent to the 3' poly(A) tract, we identified a 76-nucleotide noncoding region preceded by two overlapping reading frames (ORFs). The ultimate 3' ORF of the viral genome encodes the capsid protein, and the penultimate ORF encodes the smallest SHFV envelope protein. These two ORFs overlap each other by 26 nucleotides. Northern (RNA) blot hybridization analyses of cytoplasmic RNA extracts from SHFV-infected MA-104 cells with gene-specific probes revealed the presence of full-length genomic RNA as well as six subgenomic SHFV-specific mRNA species. The subgenomic mRNAs are 3' coterminal. In its virion morphology and size, genome structure and length, and replication strategy, SHFV is most similar to lactate dehydrogenase-elevating virus, equine arteritis virus, and porcine reproductive and respiratory syndrome virus.

Venezenin: a new bioactive Annonaceous acetogenin from the bark of Xylopia aromatica

Asimicin and a new cytotoxic Annonaceous acetogenin, venezenin [1], were isolated from the bark of Xylopia aromatica by bioactivity-directed fractionation using lethality to brine shrimp. Compound 1 represents an unusual type of C37 Annonaceous acetogenin, lacking either tetrahydrofuran (THF) or epoxide rings and possessing a double bond located two methylenes away from a vicinal diol in the hydrocarbon chain. The structure of 1 was elucidated by 1H- and 13C-nmr, COSY, single-relayed COSY, and by HMBC techniques, and derivatization. Annomontacin 10-one [6] and 18/21-cis-annomontacin-10-one [7], two semi-synthetic mono-THF acetogenins were prepared from 1. These acetogenins showed cytotoxicity, comparable or superior to adriamycin, against three human solid tumor cell lines. Reduction of the 10-keto of 1 to the racemic OH-10 derivative enhanced the bioactivity, as did the conversion of 1 to 6 and 7. Venezenin [1], like other Annonaceous acetogenins, showed inhibition of oxygen uptake by rat liver mitochondria and demonstrated that the THF ring may not be essential to this mode of action.

Meliavolkenin, a new bioactive triterpenoid from Melia volkensii (Meliaceae)

Meliavolkenin, a new triterpene with an apotirucallane skeleton, has been isolated from the root bark of Melia volkensii (Meliaceae) by bioactivity-directed fractionation using the brine shrimp lethality test. The structure has been elucidated using spectral and chemical data. The relative stereochemistries were determined by reduction and acetonide derivations, and the ring conformations were analyzed using the results of NOESY experiments. Meliavolkenin was bioactive in the brine shrimp lethality test and gave moderate cytotoxicities against three human solid tumor lines.

A role for protein kinase C-mediated phosphorylation in eliciting glucagon desensitization in rat hepatocytes

An immobilized hepatocyte preparation was used to show that both vasopressin and glucagon could desensitize the ability of glucagon to increase intracellular cyclic AMP concentrations. This process was not dependent on any influx of extracellular Ca2+ and was not mediated by any rise in the intracellular level of Ca2+. The protein kinase C-selective inhibitors chelerythrine, staurosporine and calphostin C acted as potent inhibitors of the desensitization process but with various degrees of selectivity regarding their ability to inhibit the desensitizing actions of glucagon and vasopressin. The protein phosphatase inhibitor okadaic acid was just as potent as vasopressin and glucagon in causing desensitization. Treatment of hepatocyte membranes with alkaline phosphatase restored to near control levels the ability of glucagon to stimulate adenylate cyclase activity in membranes from both glucagon- and vasopressin-treated (desensitized) hepatocytes. It is suggested that the desensitization of glucagon-stimulated adenylate cyclase activity involves a reversible phosphorylation reaction with the likely target being the glucagon receptor itself.

Analysis of simian hemorrhagic fever virus (SHFV) subgenomic RNAs, junction sequences, and 5' leader

Full-length simian hemorrhagic fever virus (SHFV) genome RNA (about 15 kb in length) and six subgenomic RNAs, ranging in size from 0.65 to 4.7 kb, were detected by Northern blot hybridization in MA104 cytoplasmic extracts with a 3' genomic antisense probe. The 5' regions of the two smallest subgenomic RNAs (RNAs 6 and 7) were cloned and sequenced. Sequence analysis indicated that these two RNAs contained a common 5' leader sequence joined to the subgenomic RNA bodies via a highly conserved junction sequence; the junction sequence of RNA 7 was 5'-TTAACC-3', while that of RNA 6 was 5'-TCAACC-3'. The complete 5' leader sequence (208 nt) was obtained from genomic RNA. The genomic 5' junction sequence is identical to that of RNA 7. Northern blot hybridization with an antisense 5' leader probe confirmed the presence of the complete leader sequence in all six species of subgenomic RNA. In its virion morphology, genome size, gene order, and replication strategy, SHFV is most similar to viruses such as equine arteritis virus, lactate dehydrogenase-elevating virus, and Lelystad virus/porcine respiratory and reproductive syndrome virus.

The analysis of disparity evoked potentials by a new form of static random-dot stereograms

PURPOSE

A new form of static random-dot stereograms free of monocular clues was designed as stimulus to elicit disparity evoked potentials.

METHODS

Disparity evoked potentials were recorded in 40 stereo-normal subjects. The stimulator was a white-black static random-dot stereograms generated by a computer and had no monocular clues. Every subject was tested in disparity stimulus, zero disparity stimulus, monocular stimulus and wearing prism condition.

RESULTS

A characteristic wide positive wave at about 250 ms was consistently recorded in disparity stimulus, which may be regarded as evidence of the presence of stereopsis. In contrast, recordings for zero disparity stimulus, monocular vision, stimulus and wearing prism condition all demonstrated a markedly difference from recording for disparity stimulus.

Specific suppression by prostaglandin E2 of activation-induced apoptosis of human CD4+CD8+ T lymphoblasts

Receptors (Rs) for prostaglandin E2 (PGE2) of the EP2 subtype are expressed at high levels in rodent and human thymuses, with preferential localization on immature thymocytes. Human cultured lymphoblasts of the Tsup-1 line express CD4 and CD8 but only a low level of CD3, typical of immature thymocytes, and bear EP2-type Rs for PGE2 that were identified by binding of [3H]PGE2 and Ab to recombinant EP2Rs, and by cAMP responses to PGE2. PGE2 protected Tsup-1 cells from apoptosis initiated by diverse stimuli, including mitogenic lectins and anti-Fas or anti-CD3 plus anti-CD28 Abs, but not ionomycin, as assessed by suppression of both fragmentation of [3H]thymidine-labeled DNA and appearance of free 3'-OH ends of cleaved DNA. An EP2R-selective synthetic agonist also significantly suppressed lectin-induced apoptosis of Tsup-1 cells. Phosphodiesterase inhibition synergistically enhanced PGE2-induced increases in cAMP and decreases in apoptosis in parallel, which suggests that the EP2R-specific protective effect of PGE2 is mediated predominantly by cAMP suppression of apoptosis. Dibutyrylcyclic AMP alone protected Tsup-1 cells against lectin-induced apoptosis, but the maximal effect was less than that for PGE2. The thromboxane A2 mimetic U46619 initiated apoptosis of Tsup-1 cells that was suppressed significantly by PGE2. Immune negative selection of immature thymocytes thus may be regulated by opposing effects of endogenous eicosanoids that include destruction by thromboxane A2 and protection by PGE2.

A new cytotoxic dihydroxy sterol from the soft coral Alcyonium patagonicum

A new sterol, 24-methylenecholest-4-ene-3 beta,6 beta-diol [1] was isolated from the soft coral Alcyonium patagonicum collected from the South China Sea. Its structure was determined by spectral analysis. Compound 1 was cytotoxic against the P-388 cell line with an IC50 value of 1 microgram/ml.

Diarrhoea in piglets and monkeys experimentally infected with Balantidium coli isolated from human faeces

Ten piglets and four monkeys free from Balantidium were dosed with human faecal homogenate which contained 1.2 x 10(4)-4.8 x 10(4) B. coli cysts. The infection resulted in severe diarrhoea in piglets 1-6 and hydrocortisone-treated monkeys 1-2, moderate diarrhoea in piglets 7-10 and a subclinical infection in monkeys 3-4. In piglets 1-3 and monkeys 1-2, heavy infection of the intestinal mucosa extended from the terminal ileum to the rectum and the mucosa was severely damaged. In piglets 4-10, infection was heavy in the large intestine with moderate mucosal damage.

Specific suppression by prostaglandin E2 of activation-induced apoptosis of human CD4+CD8+ T lymphoblasts

Receptors (Rs) for prostaglandin E2 (PGE2) of the EP2 subtype are expressed at high levels in rodent and human thymuses, with preferential localization on immature thymocytes. Human cultured lymphoblasts of the Tsup-1 line express CD4 and CD8 but only a low level of CD3, typical of immature thymocytes, and bear EP2-type Rs for PGE2 that were identified by binding of [3H]PGE2 and Ab to recombinant EP2Rs, and by cAMP responses to PGE2. PGE2 protected Tsup-1 cells from apoptosis initiated by diverse stimuli, including mitogenic lectins and anti-Fas or anti-CD3 plus anti-CD28 Abs, but not ionomycin, as assessed by suppression of both fragmentation of [3H]thymidine-labeled DNA and appearance of free 3'-OH ends of cleaved DNA. An EP2R-selective synthetic agonist also significantly suppressed lectin-induced apoptosis of Tsup-1 cells. Phosphodiesterase inhibition synergistically enhanced PGE2-induced increases in cAMP and decreases in apoptosis in parallel, which suggests that the EP2R-specific protective effect of PGE2 is mediated predominantly by cAMP suppression of apoptosis. Dibutyrylcyclic AMP alone protected Tsup-1 cells against lectin-induced apoptosis, but the maximal effect was less than that for PGE2. The thromboxane A2 mimetic U46619 initiated apoptosis of Tsup-1 cells that was suppressed significantly by PGE2. Immune negative selection of immature thymocytes thus may be regulated by opposing effects of endogenous eicosanoids that include destruction by thromboxane A2 and protection by PGE2.

Stable SV40-transformation and characterisation of some DNA repair properties of fibroblasts from a trichothiodystrophy patient

To characterize nucleotide excision repair properties of cells from trichothiodystrophy (TTD) patients genetically-related to the xeroderma pigmentosum (XP) group D, TTD skin fibroblasts from two unrelated patients (TTD1VI and TTD2VI) belonging to the TTD/XPD group were transformed with a plasmid containing SV40 large T antigen-coding sequences and some DNA repair properties, such as unscheduled DNA synthesis (UDS), UV-survival, in vitro repair synthesis of cell extracts and reactivation of UV-irradiated reporter plasmid were studied. Results showed that: a) both untransformed and transformed TTD cells present a reduced UV-survival, compared to wild-type cells, but at significantly less reduced levels than XP-D cells; b) reduced repair activities were detected in both TTD and XP-D transformed cells by using in vitro cell free extract repair and reactivation of UV-irradiated plasmid procedures, and these relative reduced extents correlated with respective UV-survival; c) surprisingly, near wild-type UDS levels were detected in TTD2VILas transformed cells at different passages after the crisis, suggesting a phenotypic reversion of this transformed cell line; d) fluoro-cytometric analysis of TTD2VILas cells revealed a strong increase of a cell population containing a DNA amount more than twice as high than that of untransformed cells; finally, e) when UDS data were normalized to the DNA content in TTD2VILas cells, it appeared that the repair efficiency was only slightly higher than in untransformed cells. This implies that in transformed cells DNA repair properties should be evaluated, taking into account additional parameters. We obtained an immortalized TTD cell line which maintains DNA repair properties similar to those of parental untransformed cells and may be used to characterize the TTD defect at genetic, molecular and biochemical levels.

Isoforms of the EP3 subtype of human prostaglandin E2 receptor transduce both intracellular calcium and cAMP signals

The EP3 subtype of prostaglandin E2 receptor transduces diverse physiological responses in mammalian tissues through signaling pathways coupled to heterotrimeric G proteins. Distinct cDNA clones encoding five isoforms of the EP3 receptor were isolated from a human uterus cDNA library. The human EP3 receptor isoforms designated hEP3-I, I', II, III, and IV are derived from alternative RNA splicing and differ only in the distal sequences of their carboxyl-terminal cytoplasmic tails. The unique cytoplasmic tails consist of 31 amino acids for isoforms I and I', 29 for II, 6 for III, and 15 for IV. When stably expressed in CHO cell transfectants, all isoforms exhibited similar EP3-specific binding of [3H]-PGE2 and PGE2 analogs. The EP3-selective agonist M&B 28767 both decreased the intracellular cAMP concentration ([cAMP]i) and increased the intracellular concentration of calcium ([Ca2+]i) with quantitative differences among different isoforms, but none mediated an increase in [cAMP]i. Pertussis toxin treatment completely blocked the decrease in [cAMP]i, but not the increase in [Ca2+]i evoked by M&B 28767. PGE2-induced desensitization of [3H]PGE2 binding by isoforms III and IV was rapid and transient, whereas that by isoform II was slow and persistent. Reverse transcription-PCR amplification of EP3 receptor messages in human kidney and uterine tissue RNA detected expression of all isoforms with different abundancies. The dual signal transduction pathways and distinctive tissue distribution of isoforms of the EP3 receptor are consistent with its mediation of diverse functions of PGE2.

[Studies on MDA and MDA/MDAa in patients with retinitis pigmentosa]

With fluorimetry, the concentration of malondialdehyde (MDA) and the ratio of MDA before and after the blood platelets activated (MDA/MDAa) were determined in patients with retinitis pigmentosa (RP). The results showed the above two parameters were statistically higher than those of the normal controls, which indicated the superoxidation metabolism increased and the blood was in a state of hypercoagulation in RP patients. The reasons for the results and their roles in RP disease were discussed. Treatments with anti-lipid, and anti-coagulation drugs combined with Chinese medicines were suggested.

Intrapleural production of interleukin 6 during mesothelioma and its modulation by gamma-interferon treatment

In vivo production of monokines was analyzed in 17 human malignant pleural mesotheliomas. High concentrations of interleukin 6 (IL-6) were detected in pleural effusions, contrasting with low levels of IL-1 beta and tumor necrosis factor alpha. This production arose from malignant cells, as shown by immunochemical analysis of pleural cells and by production of IL-6 by mesothelial cell lines. Intrapleural administration of recombinant human gamma-interferon to six patients led to a marked decrease in intrapleural IL-6 concentrations in all cases. This treatment was associated with in situ activation of macrophages and cytotoxic T-lymphocytes, as indicated by increased intrapleural neopterin and soluble CD8 concentrations. In vitro gamma-interferon had no effect on the production of IL-6 by mesothelial cell lines but decreased the growth of 3 of 6 mesothelioma cell lines. These results indicate that systemic manifestations of malignant mesothelioma, including fever, cachexia, and thrombocytosis may be related to the production of IL-6 by malignant cells, and that local gamma-interferon infusion may reduce this production by stimulating antitumoral immunity and/or by directly decreasing the proliferation of malignant cells.

A noninvasive functional evaluation following peripheral nerve repair with electromyography in a rat model

A new bipolar surface electrode array was designed and constructed for a noninvasive "closed" functional evaluation with electromyography following sciatic nerve transection in a rat model. This "closed" method was compared with a conventional one-shot "open" measurement. Nerve conduction velocity and distal latency were calculated. Data obtained from the recordings from different animals as well as from the same animal at different points in time yielded excellent reproducibilities. There is no difference in the mean values whether nerve conduction velocity and distal latency are obtained by "closed" or "open" measurements. Correlation was significant (p < 0.01; rNCV = 0.77, rDL = 0.63) between these two methods. The results lead to the conclusion that the noninvasive functional evaluation with the parameters of nerve conduction velocity and distal latency introduced in the present study could be employed as a reliable method for serial functional evaluations following nerve transection in a long-term study in a rat model.

Immunocytochemical characterization of cell lines from human malignant mesothelioma: characterization of human mesothelioma cell lines by immunocytochemistry with a panel of monoclonal antibodies

A panel of nine monoclonal antibodies was used to characterize human mesothelioma cell lines that we established from human malignant mesothelioma. The antigens detected were cytokeratin, vimentin, epithelial membrane antigen, carcinoembryonic antigen, Leu-M1 (CD15), desmin, factor VIII-related antigen (von Willebrand factor antigen), OV632, and ME1, a specific monoclonal antibody directed against human malignant mesothelioma. The technique used was the alkaline phosphatase anti-alkaline phosphatase method. All 30 cell lines, either epithelial, sarcomatous, or mixed, showed strong reactivity with cytokeratin and vimentin antibodies. None of the cell lines demonstrated any reactivity with carcinoembryonic antigen, Leu-M1, or factor VIII antibodies; moreover, all of 22 cell lines studied were positive for ME1 antibody and 10 of 12 cell lines studied were positive for OV632. Some interesting features were noted: only two of the 30 cell lines presented a weak positive staining with epithelial membrane antigen, and nine of 19 cell lines tested demonstrated a cytoplasmic staining pattern with desmin antibody. These results show that established human mesothelioma cell lines still possess the immunocytochemical characteristics that are basically consistent with the immunohistochemical features described in tumor tissues of malignant mesothelioma. These characteristics can be used to identify the mesothelioma cells grown from human malignant mesothelioma. Hence, the mesothelioma cell lines will provide a useful tool for the investigation of the cell biology of the tumor and the mechanisms of mesothelial cell transformation, as well as the in vitro evaluation of the effects of some drugs in order to develop new therapies for malignant mesothelioma.

Kneglomeratanol, kneglomeratanones A and B, and related bioactive compounds from Knema glomerata

One new phenylalkyl phenol, kneglomeratanol [1], and two new acetophenones, kneglomeratanones A [2] and B [3], together with ten known compounds, 3-(12'-phenyldodecyl)-phenol [4], 3-(10'-phenyldecyl)-phenol [5], 5-pentadecylresorcinol [6], 5-(10'-phenyldecyl)-resorcinol [7], 5-(12'-phenyldodecyl)-resorcinol [8], 2,4-dihydroxy-6-(10'-phenyldecyl)-acetophenone [9], 2-hydroxy-6-(12'-phenyldodecyl)-benzoic acid [10], formononetin, biochanin A, and 8-O-methylretusin, have been isolated from the stem bark of Knema glomerata. Brine shrimp lethality was used for the activity-directed chromatographic fractionations. All of these compounds showed moderate but significant toxicities to three human tumor cell lines and inhibited the growth of crown gall tumors on discs of potato tubers.

Specificity of DnaK-peptide binding

The sequence specificity of DnaK substrate binding has been studied using a peptide display library. Based on the amino acid patterns that appeared in this selection, short peptides were synthesized for direct measurements of DnaK affinity. The results show that peptides enriched in internal hydrophobic residues are preferential DnaK substrates, and negatively charged peptides have poor affinity. The isolated C-terminal domain of DnaK binds peptides. Peptide dissociation studies indicate that bound peptides are released from the C-terminal fragment and from DnaK at identical rates. ATP stimulates peptide dissociation from DnaK but not from the C-terminal fragment.

In vitro effects of recombinant human interferon gamma on human mesothelioma cell lines

Malignant mesothelioma is a tumor arising from serous surfaces and often related to asbestos exposure. Malignant mesothelioma is resistant to various forms of therapy. Radiotherapy, surgery or chemotherapy only slightly improve prognosis. IFN-gamma produces complete or partial responses in stage-I patients with malignant mesothelioma. The in vitro biological effect of IFN-gamma on malignant mesothelioma cells remains poorly elucidated. In the present study, 32 well-characterized human mesothelioma cell lines (HMCL) were treated with r-hu IFN-gamma at 4 doses and cell growth was determined by a colorimetric method (MTT assay). Among the 32 HMCLs tested, II exhibited significant cell-growth inhibition; 16 were insensitive to r-hu IFN-gamma, and 5 were slightly inhibited. The sensitive cell lines were strongly inhibited by r-hu IFN-gamma. Our results show that HMCL exhibit a large range of responses to r-hu IFN-gamma, some of which can be compared with those obtained in vivo in humans.

Patagonicol: a diterpenoid from the Chinese soft coral Alcyonium patagonicum

Patagonicol [1], a diterpenoid with a eunicellin skeleton, was isolated from the soft coral Alcyonium patagonicum. The structure of 1 was determined by X-ray diffraction, and detailed 1H and 13C assignments were made via 1D and 2D nmr experiments.

Early osteoinduction in rats is not altered by fibrin sealant

The angiogenic and fibrogenic activities of fibrin sealant (Tisseel) suggest that it could enhance osteoinductivity during the first days after implantation. To test this hypothesis, the osteoinductivity of sealed and unsealed bone matrix gelatin was tested by implantation into rat abdominal wall muscle pouches for two to ten days. A sponge of collagen with or without fibrin sealant was used for control. Alkaline phosphatase (ALPase) was employed to quantify osteoinduction, and myeloperoxidase (MPO) was used to determine the inflammatory reaction. Plain histologic analysis of bone matrix gelatin implants at Days 2, 4, and 10 did not demonstrate any significant differences between sealed and nonsealed implants. Histologic analysis at Day 21 confirmed the osteoinductivity of the implant. The combination of bone matrix gelatin and fibrin sealant induced an early significant increase in ALPase activity, which could be interpreted as early induction of histologically undetectable osteogenesis. A simultaneous increase in the level of MPO suggested that the bone matrix gelatin/fibrin sealant-induced ALPase reaction might be caused by an inflammatory process, but neutrophil counting did not correlate to the MPO data. Morphometry, however, seems to be insufficient to assay a heterogenous histologic distribution of singular cells. It is proposed that the ALP/MPO ratio may be used as an inflammation-independent marker of osteogenesis. This study does not support the notion of an osteoinductive potency of fibrin sealant per se; however, it is clear that fibrin sealant does not impair bone matrix gelatin-dependent osteoinduction.

[Squamous cell carcinoma associated antigen levels in monitoring the response to surgical treatment for patients with esophageal carcinoma]

The serum levels of the squamous cell carcinoma associated antigen (SCCAg) were measured in 50 patients with esophageal carcinoma by immunoradiometric assay before and after surgery. 32 patients were subjected to curative surgery, 15 palliative operation, 3 exploratory thoracotomy. After curative surgery, the elevated level dropped rapidly to normal within 72 hours. The SCCAg levels showed statistical differences. In patients having palliative operation, the SCCAg levels declined but usually remained above the normal range. After exploratory thoracotomy, the SCCAg levels usually increased. Because SCCAg responded well to the effects of surgery, it was considered to be a very useful tumor marker in monitoring the response to surgical treatment for patients with esophageal carcinoma.

[Clinical significance of serum SCC Ag in patients with squamous cell carcinoma of the lung]

To evaluate its clinical significance as a tumor marker, the serum level of squamous cell carcinoma associated antigen (SCC Ag) was studied by immunoradiometric assay in 59 patients with histologically proved lung cancer (32 squamous cell carcinomas, 23 adenocarcinomas and 4 small cell carcinomas). Carcinoembryonic antigen (CEA) was measured by radioimmunoassay simultaneously. The serum levels of SCC Ag and CEA were found above the normal range in 71.9% and 28.1% of squamous cell carcinomas, 26.1% and 34.8% of adenocarcinomas and 0% and 25% of small cell carcinomas respectively. In squamous cell carcinomas, the positive rate of SCC Ag increased with progression of clinical stage. With regard to the preoperative serum level dropped dramatically after surgery (P < 0.05). The change would be more outstanding after radical surgery (P < 0.001). The serum level of SCC Ag can be used to effectively monitor the course of disease, and could be used as an important item during the postoperative follow-up.

[Hurler syndrome (a case report)]

A case of Hurler syndrome diagnosed by clinical and laboratory examination is reported. The patient's roentgenograms showed the dystrophies of bones, lace-shaped ribs, boat-shaped cranium, fishhook-shaped forefront protrusion of silla trucica. Corneal opacities and high ocular pressure were found in both eyes. VEP measurement suggested the defects of optic nerve. The authors emphasized that visual electric physiological examinations should be used to estimate the visual functions when the patient's refractive medium is opqaue. The differential diagnosis was also briefly discussed.

Modern surgical treatment of congenital subluxated lenses

Traditional surgical management of subluxated lenses is usually associated with a high incidence of operative and postoperative complication and a poor visual outcome. We treated a series of 14 patients (26 eyes) whose visual acuity could not be improved with optical correction (phakic or aphakic) with modern microsurgery and automated suction-cutting devices. Preoperative visual acuity ranged from 0.05 to 0.3. Improvement in post-operative visual acuity was documented in all operated eyes, ranging from 0.4 to 1.0 during a follow-up period ranging from 6 to 59 months (medium 43 months). The only complication was a small accidental cut in the pupillary border in three eyes. Other complication did not occur.

The study of G6PD in erythrocyte and lens in senile and presenile cataract

The G6PD activity of erythrocytes in 113 male patients with senile and presenile cataract and 86 controls, and G6PD activity of lens in 30 patients with senile cataract and 42 controls were reported. The cataractous group had higher frequency of G6PD deficiency and lower average G6PD level in erythrocytes and lenses, but without statistical significance. The frequency of G6PD deficiency of erythrocytes in presenile cataractous group was higher than that of senile cataractous group but with no statistical significance too. However, the average G6PD level of erythrocytes in presenile cataractous group was lower than that of senile cataractous group and with statistical significance (P < 0.05). The G6PD activity of lenses only presenile in the cortex and have a positive correlation with that of erythrocytes. There was a case with deficiency of G6PD both of erythrocytes and cataractous lenses in both eyes. The results indicate that the deficiency of G6PD might be one of the cataractous pathogenetic factor for presenile cataract. Measurement of G6PD activity of erythrocytes among population might be of significance in finding the risk factor for cataract.