Effect of H-7 on cultured human trabecular meshwork cells

PURPOSE

To determine the effect of the serine-threonine kinase inhibitor H-7, which blocks actomyosin contractility and increases outflow facility in live monkeys, on morphology, cytoskeleton, and cellular adhesions of human trabecular meshwork (HTM) cells in culture.

METHODS

Cultured HTM cells were videographically recorded and evaluated before and after exposure to H-7 at different concentrations. The subcellular distribution of the actin-based cytoskeleton and associated anchor proteins including vinculin, paxillin, and beta-catenin, as well as phosphotyrosine-containing proteins were evaluated by fluorescence immunocytochemistry and digital fluorescence microscopy.

RESULTS

H-7 induced pronounced but reversible HTM cell thickening toward the cell center and deterioration of the actin cytoskeletal network. Cell-extracellular matrix (ECM) and cell-cell adhesions were also affected, but the beta-catenin-rich, vinculin-containing adherens junctions were clearly more resistant than focal contacts. Phosphotyrosine labeling in focal contacts was highly sensitive to H-7.

CONCLUSIONS

H-7 induces alterations in cell shape, actin cytoskeleton, and associated focal adhesions in cultured HTM cells, which may be responsible for the effects of H-7 on outflow facility in live monkey eyes.

[K. pneumoniea endotoxin induced mice beta-defensin-4 mRNA expression and its signaling transduction]

OBJECTIVE

To investigate the in vivo effects of Klebsiella pneumoniae endotoxin(LPS) on beta-defensin expression and the relevant signaling transduction pathway.

METHODS

A LPS tolerant mouse C3H/HeJ with a point mutation at Toll-like receptor-4 (TLR4) gene and its wild type strain C3H/HeN were used in this study. C3H/HeJ and C3H/HeN were injected with 4 mg/kg of LPS intraperitoneally. The tracheas, lungs and kidneys of the C3H/HeJ and C3H/HeN were collected respectively at different LPS-treated time points, and the total RNA of each sample was extracted. The expression of mice beta-defensin-3 and/or beta-defensin-4 mRNA in these tissues was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The sequence of cDNA amplified from the lung of C3H/HeN treated by LPS for 24 h was analyzed. By using western blot, p-I kappa B alpha (phosphorylated I kappa B alpha) and I kappa B alpha of in the lungs of C3H/HeJ and C3H/HeN were detected at different time points after treatment with LPS or without LPS.

RESULTS

1. beta-defensin-4 mRNA was detected in the lungs of C3H/HeN after 24 h treatment with LPS. In contrast, no signal was determined in C3H/HeJ mice with LPS treatment and the C3H/HeN mice without LPS treatment. 2. Compared with the control, increas of the p-I kappa B alpha was observed in the lungs of C3H/HeN at 4 h after treatment with LPS, while both the p-I kappa B alpha and I kappa B alpha contents showed a tendency to go down at 8 h after treatment and dramatically decreased at 24 h. But there were no changes in the of p-I kappa B alpha and I kappa B alpha content the lungs of C3H/HeJ under the same conditions.

CONCLUSION

K. pneumoniea endotoxin could induce the expression of beta-defensin-4 mRNA in the lung of C3H/HeN, and TLR4-mediated NF-kappa B activation signaling pathway may be responsible for this event.

[Investigation on the mechanics of adhesion to the selective extracellular matrix coated surfaces of lung cancer cells]

The adhesion properties of tumor cells with extracellular matrix(ECM) are closely associated with their invasion and metastasis. Our work reported here was intended reveal the relevant biomechanical and biorheological manifestations of human lung cancer. Using micropipette aspiration technique, we investigated quantitatively the adhesive mechanics properties of high metastatic human giant cell carcinoma(PG) cells as well as low metastatic adenocarcinoma(PAa) cells of lung based on cell culture in vitro. The results showed that the adhesion forces of PAa and PG cells to collagen IV were significantly higher than those to glass surfaces, but at the lower concentrations(1.00 microgram/ml and 2.00 micrograms/ml) of collagen IV, the amplitude for the increase of adhesion forces of PG cells were less than the amplitude for that of PAa cells, and most of the adhesion force values of PAa cells to the coated surfaces of incorporation of laminin along with 2 micrograms/ml collagen IV were significantly greater than those of PG cells. At the lower concentrations(0.625 microgram/ml for PAa cells, and 0.625 microgram/ml, 1.25 micrograms/ml for PG cells) of laminin tested, the adhesion force values of PAa and PG cells all decreased, but the amplitude and level for the decreased values of adhesion forces of PG cells were greater than those for the PAa cells. In conclusion, the adhesive and proteolytic behaviour of cancer cells to extracellular matrix might be mediated mainly by tumor cell membrane receptors such as integrin receptors and laminin receptors, it might affect the biological characteristics and the metastasis of the tumor cells. The results may benefit to explain some questions in biomechanical views about how the highly metastatic PG cells are prone to migration and invasion.

[Correlation of endotracheal tube biofilm and recurrent ventilator-associated pneumonia with Pseudomonas aeruginosa]

OBJECTIVE

To determine the correlation of endotracheal tube biofilm (ETT-BF) and recurrent ventilator-associated pneumonia with Pseudomonas aeruginosa (PA-VAP) in long-term ventilation patients.

METHODS

Pulsed-field gel electrophoresis (PFGE) of Spe I enzyme-restricted chromosomal DNA was performed to identify the DNA patterns of Pseudomonas aeruginosa from ETT-BF, pharynx and lower respiratory tract secretion in 15 VAP patients. The chromosomal DNA fingerprint profile of each strain was compared with those from all other strains to calculate the similarity by using the correlation coefficient. The strains were then grouped and groups were depicted as a dendrite using the average clustering algorithm.

RESULTS

When bacteria has been isolated from ETT-BF, the same DNA pattern species are isolated from the lower respiratory tract secretion in 7 of 15 patients. Recurrent PA-VAP is caused by closely related and indistinguishable isolates in 6 of 15 patients. All PEGE patterns from 9 patients are different from one another (correlation coefficient < 31.2%).

CONCLUSIONS

The close pathogenic relationship between ETT-BF and lower airway secretion suggests that adhesive colonization of ETTs may be an important factor in the pathogenesis of VAP.

[Determination of enantiomeric purity of (S)-(-)-alpha-phenylethylamine by NMR]

It was reported the determination of enantiomeric purities of (S)-(-)-alpha-phenylethylamine by 1H NMR, using (2R, 3R)-dibenzoyl-tartaric acid as chiral solvating agent. 1H NMR chemical shift non-equivalence of the methyl doublet of alpha-phenylethylamine was 0.08 ppm(base-line separation) in solvent CDCl3, when the concentration of the sample was 0.051 mol.L-1, the molar ratio between chiral solvating agent and the sample was 0.33. The enantiomeric purities could be determined by the peak areas of the methyl doublet of alpha-phenylethylamine. The relative standard deviation depended upon the enantiomeric purities of sample. With enantiomeric purities as high as 99.1% ee, the RSD was 0.3% (n = 4).

[The change of concentration of endothelin derived from alveolar macrophages and in induced sputum in patients with chronic bronchitis]

OBJECTIVE

To evaluate the changes of levels of endothelin (ET) in induced sputum, the culture supernatants of alveolar macrophages (AMs) and the culture supernatants of alveolar macrophages (AMs) when cultivated with aminophylline and lipopolysaccharide (LPS) in patients with chronic bronchitis and COPD. Then to investigate the role of ET derived from AMs in chronic bronchitis and COPD.

METHODS

Fourteen patients with chronic bronchitis and thirteen patients with COPD were studied. Fourteen healthy were enrolled as control. Bronchoscopy and bronchial alveolar lavage were performed routinely, BAL cells were count with hemacytometer and differentater with wright stain. Sputum induction with 4% saline was performed on twenty-six subjects. The levels of ET in BALF and in the culture supernatants of AMs were measured by radioimmunoassay methods.

RESULTS

(1) The number of all cells, neutrophils and AMs in BALF of patients with chronic bronchitis and COPD were significantly higher than those of healthy control group (P < 0.01 respectively). (2) The levels of ET in the culture supernatants of AMs and induced sputum were higher in heathy than those in patients with chronic bronchitis and COPD (P < 0.01 respectively). But there were no differences between patients with chronic bronchitis and COPD (P > 0.05 respectively). (3) Positive correlation was found between the levels of ET in the culture supernatants of AMs and those in induced sputum (r = 0.741, P < 0.01), between the number of AMs and the levels of ET in induced sputum (r = 0.597, P < 0.01). (4) Negative correlation was found between FEV(1)% of predicted value and the levels of ET in the culture supernatants of AMs in patients with COPD (r = -0.828, P < 0.01), between FEV(1)% of predited value and the levels of ET in induced sputum in patients with COPD (r = -0.748, P < 0.05). (5) In the culture with aminophylline, the level of ET derived from AMs remained stable (P > 0.05). But in the culture with LPS, the level of ET was significantly higher than that in the culture with DMEM (P < 0.01).

CONCLUSIONS

(1) The characteristics of non-specific airway inflammation in patients with chronic bronchitis and COPD is the increased numbers of neutrophils and AMs. (2) AMs are perhaps important sources of ET in the lung. LPS can stimulate AMs to secrete more ET. ET derived from AMs takes part in development of COPD.

[Expression of two types of melanoma antigens in hepatocellular carcinoma]

OBJECTIVE

To investigate the expression of melanoma antigen MAGE-4 and MAGE-10 mRNA in Chinese human hepatocellular carcinoma (HCC).

METHODS

The expression of MAGE-4 and MAGE-10 mRNA in HCC tissues and the adjacent non-HCC liver tissues was studied using RT-PCR in 48 samples of HCC. Ten samples of cirrhosis and 10 samples of normal liver tissues were examined. The PCR products were sequenced.

RESULTS

Of the 48 HCC samples studied, 15 (31.3%) and 14 (29.2%) expressed MAGE-4 and MAGE-10 mRNA respectively. In contrast, none of the HCC adjacent non-tumorous liver tissues were MAGE-4 and MAGE-10 mRNA detectable. Nor did liver tissues from cirrhosis and normal liver samples. The expression of the two genes in HCC showed no correlation with the serum level of AFP and the tumor size.

CONCLUSION

MAGE-4 and MAGE-10 mRNA are specifically expressed in Chinese HCC samples.

Determination of interaction sites of phospholipase D1 for RhoA

Phospholipase D (PLD) is regulated by many factors, including protein kinase C (PKC) and small G-proteins of the Rho and ADP-ribosylation factor families. Previous studies revealed that the interaction site of human PLD(1) for RhoA is located in its C-terminus, but the exact locus has not been determined. The purpose of the present study was to determine the interaction site of rat PLD(1) (rPLD(1)) with RhoA. Selection with phage display of different peptides of rPLD(1) confirmed that GTP-bound RhoA interacted with a site in the amino acid sequence 873-1024 at the C-terminus of rPLD(1). RhoA also associated with this peptide in a GTP-dependent manner in COS-7 cell lysates and the peptide inhibited RhoA stimulation of PLD activity in membranes from COS-7 cells expressing rPLD(1). A series of alanine mutations of non-conserved residues were made in this sequence, and the enzymes were expressed in COS-7 cells and checked for responses to activation of PKC, which interacts with the N-terminus of PLD(1), and also to the constitutively active V14RhoA. Mutations in the C-terminus of rPLD(1) (K946A, V950A, R955A and K962A) caused partial loss of V14RhoA stimulation, and double mutations (K946A/K962A, K946A/V950A and K962A/V950A) caused an almost total loss. Co-immunoprecipitation studies also showed that the mutated forms of rPLD(1) described above failed to bind V14RhoA compared with wild-type rPLD(1), whereas rPLD(1) with mutations outside the region K946-K962 bound V14RhoA normally. It is concluded that basic amino acids in a restricted C-terminal region of rPLD(1) are important for binding of RhoA and its activation of PLD activity.

A correlation between differential structural features and the degree of endopeptidase activity of type A botulinum neurotoxin in aqueous solution

Botulinum neurotoxin type A is one of the most toxic substances known to man (LD(50) for mouse 0.1 ng/kg). It is also an effective therapeutic drug against involuntary muscle disorders and for pain management. BoNT/A is a Zn(2+) endopeptidase which selectively cleaves SNAP-25 (synaptosomal-associated protein of 25 kDa), a critical component of the exocytotic machinery. Based on nucleotide sequence, BoNT/A is a 145 kDa protein, which appears as a 145 kDa protein band on sodium dodecyl sulfate--polyacrylamide gel electrophoresis. We have examined the structure of BoNT/A in aqueous solution, and found the structure in aqueous solution differs dramatically from that resolved by X-ray crystallography, both at secondary and at quaternary levels. In terms of secondary structure, BoNT/A in aqueous solution has about 47% beta-sheet structure as revealed by infrared spectroscopy, while X-ray crystallography revealed only 17% beta-sheet structure. In terms of quaternary structure, the estimated molecular mass of the native BoNT/A in aqueous solution ranged between 230 and 314 kDa, based on results from different chemical and biophysical techniques (native gel electrophoresis, chemical cross-linking, size exclusion chromatography, and fluorescence anisotropy). These results indicate that BoNT/A exists as a dimer in aqueous solution, which contrasts with the reported monomeric structure of BoNT/A based on X-ray crystallography. The dimeric form of BoNT/A can self-dissociate into the monomeric form at a concentration lower than 50 nM. This concentration-dependent structural change has a significant impact on the endopeptidase activity of BoNT/A: the catalytic efficiency of the monomeric BoNT/A is about 4-fold higher than that of its dimeric form. This difference implies a sterically restricted catalytic site of BoNT/A in the dimeric form of BoNT/A.

[Alveolar macrophage and airway inflammation in patients with chronic obstructive pulmonary disease]

OBJECTIVE

To investigate the effects of alveolar macrophage(AM) on airway inflammation of chronic obstructive pulmonary disease(COPD).

METHODS

Broncho alveolar fluid(BALF) and bronchial mucosa biopsies were performed as usual. The levels of macrophage inflammatory-1 alpha (MIP-1 alpha), gelatinase B (MMP-9), interleukin(IL)-8 in BALF and the culture supernatants of AMs were measured with ELISA. The levels of endothelin (ET) were measured with radioimmunoassay method. The AMs expressing lymphocytic functional associated antigen-1 (LFA-1) in BALF, the AMs in mucosa and the thickness of mucosa were measured with immunocytochemistry and immunohistochemistry technique.

RESULTS

The levels of MIP-1 alpha, MMP-9, IL-8 and ET in the culture supernatants of AMs in patients with COPD were (1 446.9 +/- 126.7) microg/L, (16.98 +/- 5.15) microg /L, (43.98 +/- 5.54) ng/L, (168.10 +/- 21.22) microg/L respectively; while those were (1 123.5 +/- 90.6) microg/L, (5.24 +/- 0.93) microg/L, (25.99 +/- 6.05) ng/L, (124.68 +/- 9.96) microg/L in a control group. The number of macrophages in mucosa in patients with COPD was (1.71 +/- 0.48) cells/Hp, while that was (0.59 +/- 0.18) cells/Hp in the control group (0.63 +/- 0.25) x 10(4). Statistical significance was found between the two groups. The number of AMs and polymorphonuclear leucocyte in BALF were inversely correlated with forced expiratory volume in one second as percentage of predicted value(FEV(1)% Pre) (r = -0.511, P < 0.01; r = -0.562, P < 0.01). The levels of MMP-9 and ET in the culture supernatants of AMs were inversely correlated with FEV(1)% Pre(r = -0.678, P < 0.01; r = -0.871, P < 0.01). Both the level of MIP-1 alpha and the positive number of AM expressing LFA-1 in BALF were positively correlated with the number of AMs in BALF(r = 0.572, P < 0.01; r = 0.625, P < 0.01).

CONCLUSION

AM may be involved in the process of airway inflammation and subsequent airway obstruction.

[A study of hepatitis B virus(HBV) anti-genome and its inhibitory effect on HBV replication]

OBJECTIVE

To study the combination of triplex forming oligodeoxynucleotides (TFO) with hepatitis B virus gene and its effect on replication of HBV.

METHODS

An oligodeoxynucleotide (TFO20) which can form triplex with SP1 sites in HBV core promoter was synthesized and was linked with biotin. Both the liposome-TFO20 and naked TFO20 were transfected to HepG2.2.15 cells, which was detected by SABC assay and showed signals that TFO20 was combined with HBV DNA. ELISA, reverse transcript (RT)-PCR and fluorescence quantitative PCR were used to investigate the change of HBV DNA, 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg in HepG2.2.15 cells before and after treatment with TFO20.

RESULTS

The ratio of liposome-TFO20 and naked TFO20 transfected to HepG2.2.15 cells were 80% and 40%, respectively. TFO20 signals mainly distributed in the nucleus and cytoplasm. After treatment with TFO20, the level of HBV DNA was reduced from 10(7.01) to 10(4.94), while 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg were also reduced by 70.2%, 31.6%, 37.0%, 78.2% respectively.

CONCLUSIONS

TFO20 can be transfected into cells by packing with liposome and can be combined with HBV DNA. TFO20 can effectively inhibit replication of HBV.

[The research and application of ultrasonic blood densitometer]

This paper presents an ultrasonic blood densitometer for dynamic measuring blood density. Compared with traditional blood densitometer, the ultrasonic blood densitometer has the advantages of high precision, fast response and little sample etc.

Effects of free radicals and amyloid beta protein on the currents of expressed rat receptors in Xenopus oocytes

OBJECTIVE

To investigate the effects of free radicals (FRs) and amyloid beta protein 1-40 (A beta 1-40) on the functions of expressed neurotransmitter receptors (NRs) in Xenopus oocytes.

METHODS

Total RNA and messenger RNA (mRNA) was prepared from 3-month-old Wistar rat brain tissues with Promega kits and microinjected into maturated Xenopus oocytes (stages V-VI) with 50 nl (50 ng) for each oocyte. The microinjected oocytes were incubated with modified Bath's solution at 19.0 degrees C +/- 1.0 degree C for receptor expression and their currents were recorded with double electrode voltage clamp technique. Superoxide anion free radicals (SAFRs) were produced via a reaction system (HPX/XO) with hypoxanthine (HPX, 0.05 mol/L) and xanthine oxidase (XO, 0.1 U/L). In order to observe the effects of A beta and SAFRs on the expressed glutamate receptor, HPX/XO and A beta 1-40 were added to incubation solution at 12 h, 24 h and 96 h before recording.

RESULTS

The results showed that the oocytes expressed functional NRs originating from rat brain tissues. These NRs included muscarinic acetylcholine (mACh), glutamate (Glu), dopamine (DA), serotonin (5-HT) and gamma-aminobutyric acid (GABA). The current characteristics of expressed receptors were inward currents carried by chloride ion with their equibrilium potentials close to -22 mV. The extent of effect on the current of expressed glutamate receptor from rat brain was different among different A beta concentrations and incubation times. A beta 1-40 at a concentration of 20 nmol/L had little effect on the currents of expressed rat brain glutamate receptors up to 24 h of incubation period; but the currents of glutamate receptor were significantly decreased (25% off, P < 0.01) in the treatment of 60 nmol/L A beta 1-40 over 24 h. Moreover, when 20 nmol/L A beta 1-40 was co-incubated over 12 h with SAFRs produced by the reaction system of HPX/XO, it was found that the currents of expressed rat brain glutamate receptors had been changed markedly. When the oocytes were co-treated with 60 nmol/L A beta 1-40 and SAFRs over a period of 12 h, the currents of glutamate receptor significantly decreased (21% off, P < 0.05), and the decreased percentage reached 52% over 24 h co-treatment with 60 nmol/L A beta 1-40 and SAFRs. In addition, vitamin E had a partial effect against this inhibitory effect.

CONCLUSION

The results suggest that A beta has a kind of inhibitory effect upon the current of the glutamate receptor, similar to the effects of free radicals. The effects can be antagonized by vitamin E. These imply that A beta may play a role via inhibiting receptor function in the pathophysiology of Alzheimer's disease.

Secretory response of endothelin-1 in cultured human glomerular microvascular endothelial cells to shear stress

The shear-induced secretory response of endothelin-1 (ET-1) by human microvascular endothelial cells was studied using paired human glomerular microvascular endothelial cell (HGMEC) cultured monolayers exposed to steady-state laminar shear stress for up to 10 hours. The first cell monolayer was subjected to a shear stress of 0.65 N m-2 and the second, 1.3 N m-2. ET-1 secretion was determined by radioimmunoassay. Over 10 hours of shear, the total cumulative secretion of ET-1 was 237.4 pg/cm2 for the monolayer exposed to 1.3 N m-2 and 143.6 pg/cm2 for the monolayer exposed to 0.65 N m-2. The average ET-1 secretion rate was 20.90 +/- 2.15 and 12.45 +/- 1.05 pg/cm2.h at 0.65 N m-2 and 1.3 N m-2, respectively. The results showed that ET-1 secretion varied with the time of shear in a nonlinear fashion. Although the level of shear stress affected the absolute value of ET-1 cumulative secretion and secretion rate, the major secretion period for both monolayers occurred between 2.0 and 8.0 hours, with the peak secretion rate occurring at approximately 5 hours. Thus, the response of cultured human microvascular endothelial cells to shear stress differed from that of large vessel endothelial cell cultures in terms of ET-1 secretion. In addition to the level of shear stress, the time of shear was also an important determinant of ET-1 secretion. Consequently, the heterogeneity of vascular endothelial cells and the time of shear should both be considered in future research on the secretion of vascular endothelial cell cultures.

[In situ IR study of the reaction behavior of transition metal oxides-propionic acid system, Fe2Cr(mu 3-O) (mu-O2CC2H5)6(H2O)3Cl.xH2O and Cr3 (mu 3-O) (mu-O2CC2H5)6(H2O)3NO3.xH2O]

The reaction behavior of the title complexes have been investigated by means of in situ IR in nitrogen atmosphere. It has been found that they enabled the propionic acid to convert to acetaldehyde and pentanone in different temperature. The sequence of the ketonization reaction activity for metal oxides Fe3O4 > MnO2 > Cr2O3 > Co2O3 > Ni2O3 has analogy to that for metal clusters [Fe2MnOPH] > [Fe3OPH] > [Fe2CrOPH] > [Fe2CoOPH] > [Fe2NiOPH] > [Cr3OPH][OPH = (mu 3-O)(mu-O2CC2H5)6(H2O)3]. For the ketonization reactions, the reaction temperatures of transition-metal oxides were much higher than that of corresponding metal clusters [Fe2MOPH]. It has been verified that the active component of metal cluster [Fe2MOPH] is not the corresponding transition-metal oxides. The difference between Fe3O4 and Fe2O3 which catalyze the conversion of propionic acid to acetaldehyde and pentanone respectively were demonstrated.

[In situ IR study of the reaction behavior of clusters [VnCr3-n (mu 3-O) (mu-O2CCH3)6(THF)3]X[n = 0-3, X = Cl-, ClO4-, (VO5)0.5-] and [VnFe3-n(mu 3-O) (mu-O2CCH3)6(THF)3]X(n = 0-3, X = Cl-) in nitrogen atmosphere]

The reaction behavior of the title complexes have been investigated by means of in situ IR in nitrogen atmosphere. It has been found that they enabled the acetic acid to convert to acetone and methane in different temperatures. The results indicate that the sequence of the ketonization reaction activity for the clusters was [V3OAT] > [VFe2OAT], [V2CrOAT] > [Fe3OAT], [VCr2OAT] > [Cr3OAT] [OAT = (mu 3-O) (mu-O2CCH3)6 (THF)3], and the sequence of the methanation reaction activity for the clusters was [Cr3OAT] > [VCr2OAT], [V2CrOAT] > [V3OAT] > [VFe2OAT], [Fe2OAH]. The ketonization reaction activity of [Fe3OAT] were obviously lower than that of [Fe3OAH] [OAH = (mu 3-O) (mu-O2CCH3)6 (H2O)3] and the methanation reaction activity of [Cr3OAT] were also much lower than that of [Cr3OAH]. The difference between [Fe3OAH], [Cr3OAT] and [Fe3OAH], [Cr3OAH] mentioned above were discussed.

Investigation on the rheological properties of hepatocellular carcinoma cells and their relevance to cytoskeleton structure

OBJECTIVE

To investigate the relevance of the rheological properties, i.e., viscoelasticities and adhesion to basement membrane components coated surface, of both hepatocytes and hepatocellular carcinoma (HCC) cells to the cytoskeleton structure.

METHODS

Micropipette aspiration technique was adopted to measure viscoelastic coefficients and adhesion forces to 2 microg/ml collagen IV/1.25 microg/ml laminin coated surface of the cells. Two kinds of cytoskeleton perturbing agents, colchicine and cytochalasin D, were used to treat both HCC cells and hepatocytes and the effects of these treatments on cell viscoelastic coefficients and cell adhesion forces were investigated.

RESULTS

Upon treatment of cells with colchicine in a concentration range of 1 to 60 mg/L, the elastic coefficients, especially the first elastic coefficient K1, and adhesion forces of hepatocytes generally tended to increase or increased significantly while, in contrast, viscoelastic coefficients and adhesion forces of HCC cells decreased obviously. Upon treatment of cells with cytochalasin D in a concentration range of 0.25-5.00 mg/L, viscoelastic coefficients of both hepatocytes and HCC cells decreased uniformly, with a larger magnitude for the decrease in elastic coefficients and adhesion forces of HCC cells than for those of hepatocytes. Adhesion forces of hepatocytes and HCC cells onto collagen IV/laminin coated surface varied similarly as viscoelastic coefficients under the action of the cytoskeleton perturbing agents. A significant positive correlation existed between changes of HCC cell adhesion forces on collagen IV/laminin coated surfaces and those of cell elastic coefficients (P<0.01).

CONCLUSIONS

The effects of cochicine and cytochalasin D on rheological properties of HCC cells differed significantly either in ways or extents from those on rheological properties of hepatocytes. These results might reflect the difference in the state of cytoskeleton structure and function among these two kinds of cells.

Genetic mapping of commercially significant starch characteristics in wheat crosses

Starch properties were measured on the doubled haploid progeny of 2 crosses, one between Cranbrook and Halberd and the other between CD87 and Katepwa. Properties studied included starch peak and final viscosity measured by Rapid Visco Analyser, starch granule size distribution measured by laser light scattering, starch gelatinisation temperature by differential scanning calorimetry, and flour swelling volume. In the Cranbrook Halberd cross (samples from 2 environments), a highly significant quantitative trait locus (QTL) was located on chromosome 4A for both starch peak viscosity and starch/flour swelling volume, centred around the Wx-B1 locus. In previous studies, this locus has been found to be linked to Japanese noodle quality. The increases in starch peak viscosity and flour swelling volume are derived from the Halberd parent, consistent with the fact that Halberd is null for the Wx-B1 locus on chromosome 4A and is missing the respective granule-bound starch synthase protein, whereas Cranbrook is a wheat line carrying the normal 3 Wx loci. The final starch viscosity also showed an association with the Wx-B1 locus. In the CD87 Katepwa cross, the progeny showed an association between peak viscosity and a marker on chromosome 7A. This appeared to be near the Wx-A1 locus. In some experiments, flour viscosity showed a highly significant QTL on chromosome 7B, apparently at the same locus as the late maturity - amylase derived from the Cranbrook parent. Starch gelatinisation onset temperature indicated a significant QTL on chromosomes 2B and 7A (LOD = 2.58 and 3.66, respectively, in interval analyses). Starch gelatinisation peak temperatures indicated a QTL on chromosome 7A, which, although not in the significant (P = 0.05) class based on regression analyses, indicated a LOD score of 3.06 in interval analyses. Heat of gelatinisation (H) indicated a suggestive QTL (LRS = 14.5 with a threshold of 14.7 for P < 0.05, LOD = 2.65 for interval analysis), on chromosome 4A, at the Wx-B1 locus with an increased effect coming from the Halberd parent. The A:B granule ratio analysis indicated a significant QTL on chromosome 4B, but this was not observed in all environments and may be due to the fact that the QTL corresponded to the position of a major QTL controlling plant growth.

pH and external Ca(2+) regulation of a small conductance Cl(-) channel in kidney distal tubule

A single channel characterization of the Cl(-) channels in distal nephron was undertaken using vesicles prepared from plasma membranes of isolated rabbit distal tubules. The presence in this vesicle preparation of ClC-K type Cl(-) channels was first established by immunodetection using an antibody raised against ClC-K isoforms. A ClC-K1 based functional characterization was next performed by investigating the pH and external Ca(2+) regulation of a small conductance Cl(-) channel which we identified previously by channel incorporation experiments. Acidification of the cis (external) solution from pH 7.4 to 6.5 led to a dose-dependent inhibition of the channel open probability P(O). Similarly, changing the trans pH from 7.4 to 6.8 resulted in a 4-fold decrease of the channel P(O) with no effect on the channel conductance. Channel activity also appeared to be regulated by cis (external) Ca(2+) concentration, with a dose-dependent increase in channel activity as a function of the cis Ca(2+) concentration. It is concluded on the basis of these results that the small conductance Cl(-) channel present in rabbit distal tubules is functionally equivalent to the ClC-K1 channel in the rat. In addition, the present work constitutes the first single channel evidence for a chloride channel regulated by external Ca(2+).

Corneal macrophage infiltrates following ocular herpes simplex virus type 1 challenge vary in BALB/c mice vaccinated with different vaccines

Macrophage cell infiltrates in the cornea were examined following ocular herpes simplex virus type 1 (HSV-1) challenge of vaccinated BALB/c mice. Mice were vaccinated with individual HSV-1 glycoproteins, cocktails of different HSV-1 glycoproteins, or live avirulent HSV-1 (strain KOS). Cryostat sections of cornea were taken at different times after challenge and reacted with M1/70, F4/80, BM8, or MOMA-1 monoclonal antibodies. The pattern of macrophage responses in the cornea differed depending on the vaccine that was given prior to HSV-1 ocular challenge. No macrophage response was detected in mice vaccinated with the highly protective 5gPs consisting of the five glycoproteins gB, gC, gD, gE, and gI. In contrast, mock vaccinated mice and mice vaccinated with gK, which is known to exacerbate HSV-1 induced eye disease, had high sustained macrophage responses. Mice vaccinated with 7gPs (5gPs+gG and gH) had moderate levels of macrophages. It appeared that (1) the most effective vaccines induced no detectable infiltrating macrophages in the eyes, while the least efficacious vaccines had very high levels of infiltrating macrophages; (2) presence of CD11b(+) cells in the cornea appeared to correlate with enhanced blepharitis, but did not appear to affect corneal scarring; and (3) presence of F4/80(+) cells in the cornea tended to correlate with increased corneal scarring.

Expression of the MAGE-1 gene in human hepatocellular carcinomas

OBJECTIVE

To further investigate the expression of MAGE-1 gene in hepatocellular carcinoma (HCC).

METHODS

The tumors and adjacent liver tissue from 45 HCC patients and liver tissue from 28 non-HCC patients (16 with liver cirrhosis and 12 with normal liver) were characterized by RT-PCR. A 421 bp PCR product from a cDNA fragment spanning exons 1, 2 and 3 was sequenced. The HLA type was assayed by standard ELISA in 43 HCC patients.

RESULTS

Thirty-two of 45 tumor tissues from HCC patients expressed MAGE-1 mRNA (71.1%). In contrast, MAGE-1 mRNA was not detected in adjacent tissues. Three were found to have point mutations at 3 identical sites resulting in the substitution of two amino acid residues. The most frequent HLA types in 43 HCC patients were: HLA-A2, 53.5%; A11, 25.6%; A24, 20.9%; A33, 20.9%; HLA-B13, 28.3% and B35, 23.2%. Expression of HLA-A33 (20.9%) was higher in HCC patients than that predicted in the normal Chinese population (8.8%). There was no discemable correlation between MAGE-1 expression and alpha-FP level, tumor size and hepatitis B or C virus infection. The identification of peptides which are restricted by haploptypes other than A1 should increase the opportunity for peptide based immunotherapy.

CONCLUSIONS

This study shows that MAGE-1 mRNA is highly expressed in HCC tumor tissue in Chinese patients. Previously unreported point mutations in the MAGE-1 gene are described and may also provide additional opportunities for immunotherapy.

[Studies on the infrared spectra of clusters containing O3MoS3, [Mo(x) (CO)y(O,S-C6H4-1,2)3FezLm]n- (x = 1,2 or 3, y = 0,3,7 or 4, z = 0 or 1, L = Cl, m = 0,2, n = 1 or 2) unit and the relationship between the spectra and their structures]

The IR spectra of clusters containing O3MoS3 Unit, (Et4N) [Mo(O, S-C6H4-1,2)3](1), (Et4N)2[Mo2(CO)3(O,S-C6H4-1,2)3](2), (Et4N)2[Mo3(CO)7(O,S-C6H4-1,2)3](3) and (Et4N)2[Mo2(CO)4(O,S-C6H4-1,2)3FeCl2](4) have been investigated. The characteristic frequencies, nu (Mo(n+)-OtR) (n = 4,5), nu (Mo(n+)-ObR) (n = 0,4), nu (Mo(n+)-StR) (n = 4,5), nu (Mo(n+)-SbR)(n = 0,1,4), nu (C = O), nu (Mo(n+)-C)(n = 0,1), delta (Mo(n+)-C-O)(n = 0,1), nu (Fe(2+)-ObR) and nu (Fe(2+)-Cl) were assigned by comparing the vibrational frequencies and structure parameters of them with that of Mo-Fe-S clusters. The influences of sigma donor abilities of ligands L(-OR, -SR) on nu (Mo-C) and nu (C = O) and the effect of Mo(n+)-->Mo4+ (n = 0,1) charge transfer on nu (Mo(4+)-ObR), nu (Mo(n+)-C) and nu (C = O) have been discussed. A partial oxidation of cluster 4 to [Mo2(CO)3(O,S-C6H4-1,2)3]- (5) have been inferred according to the information from the changes of IR spectra of cluster 4 in air with time and the existence of cluster 5 was also verified by NFAB-MS of cluster 4.

[Randomized controlled trial of sequence mass screening program for colorectal cancer]

OBJECTIVE

In order to assess the effectiveness of mass screening program for colorectal cancer, a sequence mass screening program based on RPHA-FOBT and individual quantitative risk assessment model (attributive degree value, AD) was used and evaluated on its effectiveness in a randomized controlled trial.

METHODS

The residents of Jiashan county aged 30 years and over were randomized to either screening or control groups in 1989. Participants in screening group were asked to fill in a questionnaire and to submit one paper slide with stool. Participants who tested positive underwent diagnostic evaluations including flexible sigmoidoscopy and colonoscopy.

RESULTS

According to the cancer registry of Jiashan, after initial mass screening in 1989, the 8-year cumulative incidence per 1,000 of colorectal cancer in screening and control groups appeared to be 3.95 (95% CI 3.81 - 4.10) and 4.01 (95% CI 3.86 - 4.16) respectively. There was no significant statistical difference between two groups (P > 0.05). Nevertheless, the 8-year cumulative mortality for colorectal cancer in screening group (2.08 per 1,000; 95% CI 1.96 - 2.18) was reduced 14.7% comparing with the control group (2.44 per 1,000; 95% CI 2.33 - 2.55). In particular, the cumulative mortality of rectal cancer was significantly (31.7%) lower than that in control group. Log-rank test showed that survival rate of rectal cancer in screening group was higher than that in controls (log-rank = 9.01, P = 0.0027).

CONCLUSIONS

The sequential mass-screening program which based on RPHA-FOBT and ADV might reduce the mortality for colorectal cancer in the Chinese population.

[Optimizing design in tissue engineering]

Tissue engineering may provide an alternative to organ transplantation and tissue transplantation which are both suffering from the limited condition of supply, so it is one of the research high-lights. This article puts forward the viewpoint of optimizing design according to its components and makes relevant suggestion; the aim is to lay a foundation for tissue engineering.

[The modulating effect of panax pseudoginseng wall saponins on the DAG-PKC signal pathway and TNF secretion of macrophages]

OBJECTIVE

To explore the roles of panax pseudoginseng wall saponins on the DAG-PKC signal pathway and TNF secretion of macrophages.

METHODS

The changes of the activities of postburn inositol lipid signal system factors such as PLC, DAG, cytomembrane PKC, cytoplasma PKC, and intracellular calcium concentration and the secretory amount of macrophage TNF were observed.

RESULTS

Panax pseudoginseng wall saponins could reduce the increased PLC activity from 57.58 +/- 8.19 to 27.00 +/- 2.31 and the intracellular calcium concentration from 393.18 +/- 392.62 to 90.56 +/- 7.21. With the role of panax pseudoginseng wall saponins, DAG activity reduced from 488.10 +/- 40.20 to 288.30 +/- 30.00, cytomembrane PKC activity decreased from 3081.50 +/- 698.50 to 1699.50 +/- 218.50, and cytoplasmic PKC activity from 2 188.60 +/- 258.30 to 848.40 +/- 138.30. The secretory TNF amount of macrophage decreased by 55%.

CONCLUSION

Panax pseudoginseng wall saponins might play an very important role in the modulating of the DAG-PKC signal pathway and decreased TNF secretion of macrophage.

Molecular electronegative distance vector (MEDV) related to 15 properties of alkanes

Several quantitative structure-property relationship (QSPR) models between 15 basic physical properties or thermodynamic functions of alkanes and their molecular electronegative distance vectors (MEDV) are developed. For six of the properties-boiling point (BP), density (D) at 25 degrees C, refraction index (RI) at 25 degrees C, critical temperature (CT), critical pressure (CP), and surface tension (ST) at 20 degrees C-logarithmic models are found to give better results than conventional (linear) models since the values of these properties all tend to a limit with increasing carbon chain length. All models are created using multiple linear regression (MLR). Conventional models are proposed for the remaining nine physical properties or thermodynamic functions: molar volume (MV) at 20 degrees C, molar refraction (MR) at 20 degrees C, heat capacity (HC) at 300 K, enthalpy (E) at 300 K, heats of vaporization (HV) at 25 degrees C, heat of atomization (HA) at 25 degrees C, standard heat of formation (HF) at 25 degrees C, heat of formation in liquid (HFL) at 25 degrees C, and heat of formation in gas (HFG) at 25 degrees C.

[Establishment of a TLC identification method for xuanshen(radix scrophulariae)]

OBJECTIVE

To establish a TLC identification method for Xuanshen(Radix Scrophulariae).

METHOD

Using TLC with harpagoside and harpagide as reference substances.

RESULT

A TLC identification method of Xuanshen has been established. The specificity of the method has been proved by a comparative detection of Xuanshen from different habitats and several crude drugs which are easily confused with Xuanshen.

CONCLUSION

The method is simple, accurate and reliable.

[Histological study of the local-regional invasion of pyriform sinus carcinoma]

OBJECTIVE

In order to offer the basis for the operation of the pyriform sinus carcinoma, the local-regional invasion patterns of the pyriform sinus carcinoma were investigated.

METHODS

Twenty-six surgical specimens obtained from patients who undergone laryngopharyngectomy were subjected to a whole organ section study.

RESULTS

Tumors located in the lateral wall of the pyriform sinus spread mainly towards the lateral wall of the hypopharynx. Tumors located in the inner wall of the pyriform sinus spread mainly towards the larynx and opposite side pyriform sinus, the paraglottic space and thyroid cartilage were particularly frequent invaded. It was rare of the invading of the cricoid cartilage. The invasion of the epiglottis and preepiglottic space across the midline had not been found. There were two invading routines, the paraglottic space and preepiglottic space. The invasion of the paraglottic space was through the aryepiglottic fold and the inner surface of the thyroid cartilage. The invading of the preepiglottic space was through the aryepiglottic fold and the upper part of the inner surface of the thyroid cartilage.

CONCLUSIONS

The invading of the preepiglottic space was not the contraindication of the partial laryngectomy. It is practicable to preserve the laryngeal function in most of the patients while tumors located on the lateral or inner wall of the pyriform sinus. There was a tendency to the invading to the contralateral side in the inner wall of the pyriform or postcricoidarytenoid region. Attention should be paid to the submucosal spreading in the postcricoidarytenoid region.

[Melanoma antigen-3 expression in human hepatocellular carcinoma]

OBJECTIVE

To investigate the expression of melanoma antigen-3 (MAGE-3) mRNA in human hepatocellular carcinoma (HCC) and probe into the theoretical feasibility that MAGE-3 antigens can be developed as a new peptide vaccine for immunotherapy in HCC patients.

METHODS

The expression of MAGE-3 mRNA in HCC tissues and the adjacent non-HCC liver tissues was studied using RT-PCR in 45 HCC patients. The results were compared with those of 16 cirrhotic patients and 12 patients whose liver tissues were pathologically normal. MAGE-3 mRNA positive PCR products were DNA sequenced in 3 HCC patients. The sequenced fragments of MAGE-3 cDNA were used as template by which a [alpha(32)P] labeled probe was synthesized and employed for Southern blot analysis. HLA class I-A and -B typing of 43 HCC patients were assayed by ELISA.

RESULTS

Of the 45 HCC samples, 35 (78%) expressed MAGE-3 mRNA and six HCC adjacent tissues were also positive in MAGE-3 expression. Pathological examination showed cellular heteromorphism in these adjacent tissues. The non-HCC liver tissues from cirrhosis and normal liver samples were not MAGE-3 mRNA detectable. The DNA sequence confirmed that the target gene fragment in all of the 3 samples of PCR products was MAGE-3 cDNA. Southern blotting result confirmed that of RT-PCR assay. In HCC patients, the predominant types of HLA were A(2) (53.5%), A(11) (25.6%), A(24) (20.9%), A(33) (20.9%), B(13) (28.3%), and B(35) (23.2%). MAGE-3 mRNA expression in HCC showed no correlation with the level of serum AFP and the size of the tumor.

CONCLUSIONS

MAGE-3 mRNA is expressed at a high percentage of HCC samples. This tumor rejection antigen may be used as peptide vaccine for immunotherapy of HCC patients. The phenomena that some non-HCC adjacent tissues with heteromorphism can express MAGE-3 like their paired HCC tissues indicate that the expression of MAGE-3 may be an indicator in the early stage of carcinogenesis of liver tissues.

[Effects of sulpiride on morphine-induced reward and its relation to cyclic AMP levels in mice]

This study examined the effects of sulpiride, a dopamine D2 receptor antagonist, on morphine rewarding properties and its relation to cyclic AMP levels in brain. The morphine-induced reward in mice was observed in a conditioned place preference test. Cyclic AMP was estimated by radioimmunoassay. The time of staying in morphine pairing compartment and the cAMP levels in brain of mice in the morphine group increased as compared with those in other groups (P < 0.05), but there was no significant difference in the time of staying in morphine pairing compartment and the cAMP levels in brain between the saline group and the sulpiride plus morphine groups (P > 0.05). These suggest that the inhibition of morphine-induced reward by sulpiride be due to the prevention of an increase in cyclic AMP levels in brain.

[The effect of vinblastine on the viscoelastic properties of lung cancer cells]

BACKGROUND

To explore the effect of vinblastine on the viscoelastic properties of highmetastatic human giant cell carcinoma cells ( PC) and low metastatic adenocarcinoma cells (PAa) of the lung and its biomechanical mechanisms.

METHODS

The viscoelastic properties of PG and PAa cells and their changes after treated with vinblastine (VCR, 0. 10-2. 00Lg/ml) were detected by micropipette aspiration technique. Viscoelasticity was analyzed by the special three-element standard linear solid model.

RESULTS

Before treated with VCR, the elastic coefficients K1 and K2 as well as viscous coefficient L of PAa were significantly higher than those of PG cells. The values of K1, K2 and L of PAa cells decreased along with the increase of VCR concentration. However, the viscoelastic coefficient values in PG cells decreased when the VCR concentration was lower than 1. 00Lg/ml and then turned to increase as concentration of VCR went on increasing. The microtubules and microfilaments were sparse random in the PAa cells and diminished in PG cells. After treated with VCR, they were cut down seriously in PAa cells, and manifestations of mitotic arrest of cell cycle increased unusually in PG cells.

CONCLUSIONS

The cytoskeleton structure component changes are related to the viscoelasticity of the tumor cells. The anti-neoplasm actions of cytoskeleton interferents such as VCR might be realized by mainly regulating the message of tumor cells growth and differentiation.

The US5 open reading frame of herpes simplex virus type 1 does encode a glycoprotein (gJ)

Based on sequence analysis, the protein encoded by the US5 open reading frame (ORF) of herpes simplex virus type 1 (HSV-1) was predicted to contain an N-glycosylation site and was given the designation of glycoprotein J (gJ). However, the US5 gene product has not been identified and the identity of gJ as a glycoprotein has not been confirmed. We have cloned and expressed the DNA encoding the complete sequence of the US5 ORF, using a baculovirus expression system. Western blotting, using polyclonal antibody raised against synthetic US5 peptides, revealed two major baculovirus-US5-expressed protein bands with apparent molecular weights of 16-17 and 10 kD. The recombinant US5 was found on the membrane of Spodoptera frugiperda cells and was susceptible to tunicamycin, endoglycosidase H, glycosidase F and partially resistant to endoglycosidase F. Vaccination of mice with baculovirus-expressed US5 did not induce a neutralizing antibody to HSV-1 or provide protection against lethal HSV-1 challenge. However, serum from these vaccinated mice was able to recognize US5 in purified HSV-1 virions by Western blot analyses and on the surface of HSV-1-infected cells by immunofluorescence. These findings establish that US5 does encode a glycoprotein and confirm the appropriateness of naming the US5 gene product gJ.

[Proliferating cell nuclear antigen (PCNA) in ovarian carcinoma and its relation to lymph node metastasis and prognosis]

OBJECTIVE

To investigate expression of proliferating cell nuclear antigen (PCNA) in ovarian epithelial cancer and its relation to lymph node metastasis, second-look laparotomy (SLL) and prognosis.

METHODS

Monoclonal antibody PC10 was used to stain PCNA in archival paraffin-embedded tissues.

RESULTS

PC10 immunostaining was performed successfully in all 74 primary and 31 intraperitoneal metastatic tumors. The expression of PCNA was significantly elevated in 31 metastatic tumors compared with their primary tumor from the same patient (7.94 vs 6.89, P = 0.042). The expression was more marked in bilateral than in unilateral ovarian cancer but it was not associated with lymph node metastasis, clinical stage, histologic grade and subtype. In 28 patients with stage III ovarian cancer undergone SLL, the mean immunoreactive score (IRS) of PCNA of the primary tumor was significantly higher in patients with negative SLL than in those with positive SLL (7.59 vs 6.10, P = 0.03). Since chemotherapy was performed following surgical debulking, negative SLL more frequently seen in patients with high PCNA expression might suggest better chemotherapeutic sensitivity due to higher proliferation fraction of tumor cells. Univariate analysis of survival indicated that the overall survival was inversely associated with the level of PCNA expression, while multivariate analysis with Cox's model showed that independent prognostic factors were the residual tumor after primary debulking (P < 0.001) and clinical stage (P < 0.05), followed by PCNA expression (P = 0.09).

CONCLUSION

The expression of PCNA may be useful in predicting prognosis, but is not correlated with lymph node metastasis.

NMR and EPR investigations of iron corrolates: iron(III) corrolate pi cation radicals or iron(IV) corrolates?

The chloroiron corrolates of 2,3,7,8,12,13,17,18-octamethyl- and 7,13-dimethyl-2,3,8,12,17,18-hexaethylcorrole ([(Me8C)FeCl] and [(7,13-Me2Et6C)FeCl], respectively) and their bisimidazole complexes have been investigated by NMR spectroscopy as a function of temperature, and by EPR spectroscopy at 4.2 K. Magnetic susceptibilities were measured by the modified Evans method. It is found that the electron configuration of the chloroiron corrolates is that of a S = 3/2 Fe(III) center coupled to a corrolate pi radical, where one electron has been removed from the pi system of the corrolate. This pi radical is antiferromagnetically coupled to the unpaired electrons of the iron to yield an overall S = 1 complex, as evidenced by the very large positive shifts of the meso-H resonances (183 and 172 ppm). That this antiferromagnetic coupling is very strong is supported by the near-Curie behavior of the 1H chemical shifts. For the chloroiron corrolates in the presence of imidazole, imidazole-d4, and N-methylimidazole at temperatures of -50 degrees C and below, the mono- and bisligand complexes are formed. The NMR spectra can be assigned on the basis of chemical exchange between the chloroiron(III) parent complex and the bisligand complex at -30 degrees C, and between the bisligand complex and the monoligand complex at -50 degrees C. The bisimidazole complexes show pyrrole CH2 and CH3 resonances characteristic of low-spin Fe(III) centers (S = 1/2), but with strongly upfield-shifted meso-H resonances (delta values of -95 and -82.5 ppm for the octamethyl complex and -188 and -161 ppm for the dimethylhexaethyl complex at 203 K) characteristic of the presence of a macrocycle-centered unpaired electron. The magnetic moments of these bisligand complexes are somewhat lower than expected for overall S = 1 systems, and decrease as the temperature is lowered. The lower apparent magnetic moments (2.0-1.8 mu B between -50 and -90 degrees C) are believed to be caused by a combination of weak or no magnetic coupling between the metal and macrocycle electrons and decreasing solubility of the complex as the temperature is lowered. The non-Curie behavior of the 1H chemical shifts observed in the low-temperature (-50 to -90 degrees C) NMR spectra likely arises from a combination of the effects of weak antiferromagnetic coupling of metal and macrocycle spins, a low-lying electronic excited state, and ligand binding/loss equilibria at the highest temperatures studied (-50 degrees C).

Effect of latrunculin-A on morphology and actin-associated adhesions of cultured human trabecular meshwork cells

PURPOSE

Determine the effects of the actin cytoskeleton disrupting compound latrunculin-A (LAT-A) on morphology, cytoskeleton, and cellular adhesions of cultured human trabecular meshwork (HTM) cells.

METHODS

HTM cells were cultured to high confluence with endothelial-like morphology and treated with LAT-A at different doses and duration. Topography of living cells was evaluated by videomicroscopy. Distribution and organization of the actin-based cytoskeleton, vinculin- and paxillin-containing focal contacts, and beta-catenin-rich intercellular adhesions were determined by immunofluorescence and digital microscopy.

RESULTS

LAT-A induced pronounced but highly reversible rounding of HTM cells, intercellular separation, and disruption of actin filaments. beta-catenin-rich intercellular adherens junctions were particularly sensitive to LAT-A. Vinculin- and paxillin-containing focal contacts were only partially affected and appeared to be more resistant to the drug than the intercellular interactions.

CONCLUSIONS

The increase in outflow facility in the living primate eye induced by LAT-A may be due to the disorganization and disruption of the actin cytoskeleton and its associated cellular adhesions in the trabecular meshwork.

Stat1 as a component of tumor necrosis factor alpha receptor 1-TRADD signaling complex to inhibit NF-kappaB activation

Activated tumor necrosis factor alpha (TNF-alpha) receptor 1 (TNFR1) recruits TNFR1-associated death domain protein (TRADD), which in turn triggers two opposite signaling pathways leading to caspase activation for apoptosis induction and NF-kappaB activation for antiapoptosis gene upregulation. Here we show that Stat1 is involved in the TNFR1-TRADD signaling complex, as determined by employing a novel antibody array screening method. In HeLa cells, Stat1 was associated with TNFR1 and this association was increased with TNF-alpha treatment. TNFR1 signaling factors TRADD and Fas-associated death domain protein (FADD) were also found to interact with Stat1 in a TNF-alpha-dependent process. Our in vitro recombinant protein-protein interaction studies demonstrated that Stat1 could directly interact with TNFR1 and TRADD but not with FADD. Interaction between Stat1 and receptor-interacting protein (RIP) or TNFR-associated factor 2 (TRAF2) was not detected. Examination of Stat1-deficient cells showed an apparent increase in TNF-alpha-induced TRADD-RIP and TRADD-TRAF2 complex formation, while interaction between TRADD and FADD was unaffected. As a consequence, TNF-alpha-mediated I-kappaB degradation and NF-kappaB activation were markedly enhanced in Stat1-deficient cells, whereas overexpression of Stat1 in 293T cells blocked NF-kappaB activation by TNF-alpha. Thus, Stat1 acts as a TNFR1-signaling molecule to suppress NF-kappaB activation.

[Invasion behavior of hepatocellular carcinoma cells correlates with their rheological properties]

We investigated the viscoelasticity, mechanics of adhesion to collagen I coated surfaces and mechanics of adhesin to liver sinosoidal endothelial cells(LECs) among primary culture human hepatocytes, hepatocellular carcinoma(HCC) cells as well as HCC-Inv cells, namely HCC cells capable of invading the artificial basement membrane, Matrigel. The results showed that the above-mentioned rheological properties of HCC cells differed obviously from those of normal hepatocytes. HCC-Inv cells exhibited higher viscoelastic coefficients, higher adhesion forces to collagen I coated surfaces as well as higher adhesion forces to LECs than those of normal hepatocytes and HCC cells. Immunocytochemistry showed the differences in cell morphology and cytoskeleton structure between HCC cells and HCC-Inv cells. A brief discussion was presented in relation to the changes in cell rheological properties of hepatocellular carcinoma cells and their pathological significance.

[Effects of YMB injection on hemorheology in rats]

This study was designed to elucidate the mechanism of YMB Injection on anti-CAD therapy. Fufang Danshen Injection was used as positive control and saline was taken as negative control to study the effects of traditional medicine YMB Injection on hemorheological parameters in normal rats and hypostasis rats. The results showed YMB Injection had no effect on hemorheological parameters of normal rats, but it could effectively decrease whole blood viscosity and whole blood reduction viscosity of hypostasis rats. The data implied that YMB Injection could decrease blood viscosity and hence improve blood supply of the graft in anti-CAD therapy.

[Rapid determination of the ozone in water]

A new potassium iodide--N, N-diethy1-1,4-phenylen-ediammonium sulfate (DPD) spectrophotometry method for the determination of the ozone in water was established. The method was based on the quantitative reaction between the ozone and potassium iodide in buffered solution(pH 3.35): O3 + 2I- + 2H+-->O2 + I2 + H2O. Iodine could react with DPD regent and produce pink color. Its absorption was determined at 510 nm with spectrophotometer. The range of direct determination was 0-1.00 mg/L. Beer's law was obeyed in this range. The detection limit was 0.01 mg/L. The relative standard deviations were from 1.2% to 2.7% (n = 10). The recoveries were from 98.6% to 106.6%. Water samples were determined with both this method and iodimetry. The results were comparable. The method was applied to the determination of the ozone in water sample with satisfactory results. It was practical and reliable.

Influence of antimicrobial subinhibitory concentrations on hemolytic activity and bacteriocin-like substances in oral Fusobacterium nucleatum

Fusobacterium nucleatum is considered for its role in colonization of initial and late microorganisms in dental plaque and for its coaggregation with other bacterial species. It is known that action of different antimicrobial substances may interfere with either virulence factors or with host-bacteria interaction. The goal of this study was to examine the influence of subinhibitory concentrations of chlorhexidine, triclosan, penicillin G and metronidazole on hemolytic activity and bacteriocin-like substance production of oral F. nucleatum. A high resistance to penicillin G was observed and 63% of the isolates were beta-lactamase positive. All the tested isolates were susceptible to metronidazole. F. nucleatum isolates grown with or without antimicrobials were alpha-hemolytics. Bacteriocin-like substance production was increased in isolates grown with penicillin G. Impaired production of hemolytic or antagonic substances can suggest a role in the regulation of oral microbiota.

Both CD4+ and CD8+ T cells are involved in protection against HSV-1 induced corneal scarring

AIM

To determine the relative impact of CD4+ T cells and CD8+ T cells in protecting mice against ocular HSV-1 challenge.

METHODS

CD4+ T cell knockout mice (CD4-/- mice), CD8+ T cell knockout mice (CD8-/- mice), and mice depleted for CD4+ or CD8+ T cells by antibody (CD4+ depleted and CD8+ depleted mice), were examined for their ability to withstand HSV-1 ocular challenge. The parental mice for both knockout mice were C57BL/6J.

RESULTS

These results suggest that: (1) both CD4+ deficient mice (CD4-/- and CD4+ depleted mice) and CD8+ deficient mice (CD8-/-, and CD8+ depleted mice) developed significantly more corneal scarring than their C57BL/6J parental strain; (2) the duration of virus clearance from the eyes of the CD4+ deficient mice was 4 days longer than that of the CD8+ deficient mice; and (3) the severity of corneal scarring in the CD4+ deficient mice was approximately twice that of the CD8+ deficient mice.

CONCLUSIONS

It was reported here that: (1) CD4+ and CD8+ T cells were both involved in protection against lethal ocular HSV-1 infection; and (2) CD4+ and CD8+ T cells were both involved in protection against HSV-1 induced corneal scarring.

[Community characteristics of rare trees at Dalaoling of Three-Gorge reservoir area in western Hubei Province]

The quantitative characteristics, plant frequency in layers and species diversity of David involucrata var. vilnoriniara, Euptlea pleiosperma, Stewartia sinensis and Pterostyrax psilophtila communities at Dalaoling National Forest Park Reserve of Yichang were studied qualitatively and quantitatively. The community composition and structure were made clear, the succession courses and stages of the communities were revealed, and the role of these rare trees on the succession course of communities and the cause of being in imminent danger were analyzed, which provided a theoretical basis for protecting the rare trees in the Three-Gorge reservoir area.

Electronic effects in transition metal porphyrins. 10. Effect of ortho substituents on the temperature dependence of the NMR spectra of a series of spin-admixed perchloratoiron(III) tetrakis(2,6- or 2,4,6-phenyl substituted)porphyrinates

The perchloratoiron(III) complexes of a series of 2,6-disubstituted tetraphenylporphyrin ligands, where the 2,6-phenyl substituents were -H, -F, -Cl, -Br, or -OMe, as well as two 2,4,6-phenyl-substituted complexes, where the substituents were -Me and -OMe, have been investigated as a function of temperature by 1H NMR spectroscopy. Curvature in the 1/T dependence was evident in most cases. Forced linear extrapolation of the temperature dependence observed over the range of the study yielded Curie plots that include negative slopes with very large positive 1/T intercepts (Cl approximately Br > Me > H) to negative slope with near zero intercept (tri-OMe) to positive slope with very large negative intercept (F, di-OMe). The NMR results were combined with EPR spectroscopic data and curve-fitting procedures based on an expanded Curie law to arrive at a consistent overview of the variety of temperature-dependence behaviors observed. This overview relies upon the premise that, in addition to the ground state observed by EPR spectroscopy, one (or more) thermally accessible excited state(s) are populated to varying degrees over the temperature range of the NMR measurements. If only one excited state is considered, the analysis is consistent with the ground state being a largely intermediate-spin state (S = 3/2) for the majority of the complexes but a largely high-spin state (S = 5/2) for ((2,6-F2)4TPP)FeOClO3 and ((2,6-(OMe)2)4TPP)FeOClO3.

Study on biologic activity for membrane of normal bone marrow cells with infection of epidemic hemorrhagic fever virus

Using DPH fluorescence probe, the membrane of normal bone marrow cells with infection of epidemic hemorrhagic fever virus (EHFV) was labeled. The membrane lipid fluidity was obviously decreased from the membrane lipid fluorescence polarization. The membrane lipid fluidity of lymphocyte, monocyte and neutrophilic granulocyte was dynamically observed. After culturing the cells for 1, 6, 24 and 72 h, it was found that all the membrane lipid fluidity of the infected cells was decreased obviously with the longer the culturing time, the more obvious it. Compared with the normal control groups, there was a significant difference statistically (P < 0.05-0.01). It was suggested that the decrease of the membrane lipid fludity of normal bone marrow cell with infection of EHFV had correlation with the degree of virus invading and cell-function injury.

Antimicrobial effects of novel siderophores linked to beta-lactam antibiotics

As a strategy to increase the penetration of antibiotic drugs through the outer membrane of gram-negative pathogens, facilitated transport through siderophore receptors has been frequently exploited. Hydroxamic acids, catechols, or very close isosteres of catechols, which are mimics of naturally occurring siderophores, have been used successfully as covalently linked escorting moieties, but a much wider diversity of iron binding motifs exists. This observation, coupled to the relative lack of specificity of siderophore receptors, prompted us to initiate a program to identify novel, noncatechol siderophoric structures. We screened over 300 compounds for their ability to (1) support growth in low iron medium of a Pseudomonas aeruginosa siderophore biosynthesis deletion mutant, or (2) compete with a bactericidal siderophore-antibiotic conjugate for siderophore receptor access. From these assays we identified a set of small molecules that fulfilled one or both of these criteria. We then synthesized these compounds with functional groups suitable for attachment to both monobactam and cephalosporin core structures. Siderophore-beta-lactam conjugates then were tested against a panel of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus strains. Although several of the resultant chimeric compounds had antimicrobial activity approaching that of ceftazidime, and most compounds demonstrated very potent activity against their cellular targets, only a single compound was obtained that had enhanced, siderophore-mediated antibacterial activity. Results with tonB mutants frequently showed increased rather than decreased susceptibilities. suggesting that multiple factors influenced the intracellular concentration of the drugs.

Observation of T lymphocyte subsets in the liver of patients with advanced schistosomiasis and advanced schistosomiasis accompanied with hepatitis B

T lymphocyte subsets in the liver were detected by Avidin-Biotin Complex (ABC) assay in 22 patients with advanced schistosomiasis (AS) and 5 cases of AS accompanied with hepatitis B. T lymphocytes in the liver of AS patients were distributed in the peripheral layer of egg granuloma or the area near eggs in non-granuloma. No infiltrative T lymphocytes were observed in area with extensive fibrosis. There was infiltration of many T cells in the portal tract, piecemeal and focal necrosis area as well as in hepatic sinus in AS patients accompanied with hepatitis B. CD8+ T cells (suppressor/cytotoxic T cells, Ts/Tc) in the liver were predominant in the two groups. In AS patients, marked hepatic fibrosis, a small number of T cell infiltration and slight hepatocellular degeneration and necrosis were observed. However, obvious hepatocellular degeneration and necrosis were seen in AS patients accompanied with hepatitis B, and 3 cases of them developed active liver cirrhosis. The results indicated immune response was weak in the liver in AS patients and Ts cells might be predominant in the subset of CD8+ T lymphocytes. Cellular immune response was relatively strong in AS patients accompanied with hepatitis B and the infiltrative CD8+ T lymphocytes might be mainly Tc cells.

The role of natural killer cells in protection of mice against death and corneal scarring following ocular HSV-1 infection

C57BL/6 mice depleted of NK (natural killer) cells with anti-asialo-GM1 antibody were more susceptible to lethal HSV-1 ocular challenge (12% survival) than control C57BL/6 mice (100% survival), CD4+ depleted mice (100% survival), CD8+ depleted mice (80% survival), or macrophage depleted mice (85% survival). NK depletion also resulted in significantly higher levels of HSV-1 induced corneal scarring than was seen with any of the other groups. C57BL/6 mice depleted of NK cells with PK136 (anti-NK1.1 antibody which is more specific for NK cells than is anti-asialo-GM1 antibody) were also more susceptible to HSV-1 ocular challenge than T cell or macrophage depleted mice. Vaccination completely protected NK depleted mice against death and corneal scarring. In contrast to C57BL/6 mice, in BALB/c mice, NK depletion had no effect on survival or corneal scarring following ocular HSV-1 challenge. Experiments with IFN-gamma knockout mice (IFN-gamma(o/o) mice) suggested that IFN-gamma played a minor role in protection of naïve mice against death following HSV-1 challenge. However, IFN-gamma did not appear to be an important factor in protection against HSV-1 induced eye disease. Thus, protection against HSV-1 induced corneal scarring in naive mice appeared to be due to a non-INF-gamma NK function. Our results therefore suggest that NK cells were very important in protecting naive C57BL/6 mice but not vaccinated C57BL/6 mice against corneal scarring and death following ocular HSV-1 challenge.