Polarization measurements in high-energy deuteron photodisintegration

We present measurements of the recoil proton polarization for the d(gamma-->,p-->)n reaction at straight theta(c.m.) = 90 degrees for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization p(y) vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(gamma,p)n cross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.

CCR1-specific non-peptide antagonist: efficacy in a rabbit allograft rejection model

The classic signs of acute cellular rejection during organ transplantation include the infiltration of mononuclear cells into the interstitium. This recruitment of leukocytes into the transplanted tissue is promoted by chemokines like RANTES. Since RANTES is a potent agonist for the CC chemokine receptor CCR1, we examined whether the CCR1 antagonist BX 471 was efficacious in a rabbit kidney transplant rejection model. BX 471 was able to compete with high affinity with the CCR1 ligands MIP-1alpha and RANTES for binding to HEK 293 cells expressing rabbit CCR1. BX 471 was a competitive antagonist of rabbit CCR1 in Ca(2+) flux studies. Two separate studies in which animals were subcutaneously implanted with slow release pellets of BX 471 demonstrated that animals implanted with BX 471 had increased survival compared with untreated controls or animals implanted with placebo. The mean survival time for the placebo group was 12.33+/-1.7 days. The animals in the BX 471 treated group had mean survival times of 16.9+/-2.1 and 16.0+/-1.7 days, respectively, for the two studies. Analysis of the combined data by Student t-test gave a P value of 0.03 that is significant at the 0.05 level. In addition, there was a marked reduction in the urea and creatinine levels in the BX 471 treated animals compared with the control and placebo groups in both studies. Finally, pathologic analysis of the kidneys in the rabbit renal transplantation model from animals in the different groups showed that BX 471 was similar to cyclosporin in its ability to prevent extensive infarction of transplanted kidneys. Based on the data from these studies, BX 471 shows clear efficacy at the single dose tested compared with animals treated with placebo.

[Determination of warfarin in plasma by HPLC and an investigation of monitoring patients after cardiac valve replacement]

OBJECTIVE

A simple HPLC method was established for the determination of warfarin in plasma to investigate the relationship between warfarin concentration and anticoagulant effect.

METHODS

The mixture of dichloromethane and hexane (1:9) was used as extracting solvent for the plasma samples. The chromatographic separation was on C18 column with a mobile phase consisting of methanol and 50 mmol/L ammonium acetate buffer (pH2.5, 70:30).

RESULTS

The calibration curve was linear within 50-2000 ng/ml. The extraction recoveries of warfarin were 78.0%-81.6%. The recoveries of methodology were 103.1%-106.5%. Inter-day and intra-day RSD were 2.33%-5.46% and 5.29%-7.73%, respectively. This method was used for determining warfarin in 70 patients after cardiac valve replacement. The results showed that 44 cases had their INR within the safety range (1.31-2.35) recommended to Chinese, and of them 37(84.1%) cases had a warfarin level at 616.2 +/- 154.8 ng/ml.

CONCLUSION

This method is useful in monitoring warfarin concentration during anticoagulant therapy.

[The efficiency of algae removal from drinking water by ferrate]

This paper studied the efficiency of algae removal by ferrate from two kinds of raw water which were collected from Donghu and Tiegang reservoir respectively. The experimental results showed that the removal efficiency of algae reached about 95% only through PAC coagulation when the raw water was extracted from Donghu reservoir in which most of algae was Chlorella. But dealing with Tiegang raw water in which the majority of algae were Oscillatoria, terrate was used as pre-oxidant coupling with PAC coagulation not only using PAC to flocculate and the efficiency of algae removal could be up to 97.85%. However this treatment method using ferrate as pre-oxidant overmatched the traditional method prechlorination for algae removal.

Measurement of the charged pion electromagnetic form factor

Separated longitudinal and transverse structure functions for the reaction 1H(e,e(')pi(+))n were measured in the momentum transfer region Q2 = 0.6--1.6 (GeV/c)(2) at a value of the invariant mass W = 1.95 GeV. New values for the pion charge form factor were extracted from the longitudinal cross section by using a recently developed Regge model. The results indicate that the pion form factor in this region is larger than previously assumed and is consistent with a monopole parametrization fitted to very low Q2 elastic data.

A non-peptide functional antagonist of the CCR1 chemokine receptor is effective in rat heart transplant rejection

Chemokines like RANTES appear to play a role in organ transplant rejection. Because RANTES is a potent agonist for the chemokine receptor CCR1, we examined whether the CCR1 receptor antagonist BX471 is efficacious in a rat heterotopic heart transplant rejection model. Treatment of animals with BX471 and a subtherapeutic dose of cyclosporin (2.5 mg/kg), which is by itself ineffective in prolonging transplant rejection, is much more efficacious in prolonging transplantation rejection than animals treated with either cyclosporin or BX471 alone. We have examined the mechanism of action of the CCR1 antagonist in in vitro flow assays over microvascular endothelium and have discovered that the antagonist blocks the firm adhesion of monocytes triggered by RANTES on inflamed endothelium. Together, these data demonstrate a significant role for CCR1 in allograft rejection.

Intrarenal serotonin, dopamine, and phosphate handling in remnant kidneys

BACKGROUND

Serotonin (5-HT) and dopamine (DA) are intrarenal autocrine/paracrine substances that regulate phosphate reabsorption. The present studies explored intrarenal serotonin and DA metabolism and the implications for phosphate homeostasis in rats with remnant kidneys, a model for renal failure.

METHODS

The intrarenal productions of serotonin and DA were determined from measurements of renal interstitial fluid (microdialysate) and urine in rats with remnant or intact kidneys. In clearance studies, the effects of infusion of methiothepin, a serotonin receptor antagonist, or gludopa, a renal selective DA precursor, on phosphate and sodium excretion were determined in rats with a remnant or intact kidneys.

RESULTS

Renal interstitial serotonin (5-HT, 3.4 +/- 0.9 pg/min) was fourfold higher than DA (0.6 +/- 0.1 pg/min) in remnant kidneys. Conversely, urinary excretion of serotonin was fourfold less than DA in rats with a remnant kidney (5-HT 0.4 +/- 0.02 vs. DA 1.5 +/- 0.1 ng/min). Infusion of methiothepin or gludopa significantly increased the fractional excretion of phosphate (FE(Pi)) in rats with a remnant kidney from 54 +/- 3 to 67 +/- 7% (P < 0.05) and from 36 +/- 10% to 51 +/- 13% (P < 0.05), respectively.

CONCLUSION

We conclude that serotonin preferentially accumulates in the renal interstitium, whereas DA exits primarily via the tubular lumen. Phosphate excretion is increased by both the acute infusion of the serotonin receptor antagonist and the infusion of gludopa, suggesting that both serotonin and DA modulate phosphate excretion in rats with remnant kidneys.

Baculovirus expression cassette vectors for rapid production of complete human IgG from phage display selected antibody fragments

For the expression of human intact IgG antibodies, we have constructed a set of baculovirus expression vectors designed to facilitate rapid insertion of heavy and light chain genes of Fab or scFv antibodies derived from phage display antibody libraries. By linking them to human constant or Fc regions, expression of complete human immunoglobulin molecules was achieved in insect cells by infection with recombinant baculovirus. The IgG expression cassette vectors are based on the backbone vector which contains two back to back polyhedron and p10 promoters. The IgG expression cassette elements, including the authentic IgG lambda or kappa and heavy chain signal sequences, as well as light chain (lambda or kappa) and heavy chain constant region genes are combined in a single vector and are controlled by the p10 and polyhedron promoter respectively. Either of VL or Fab-L and VH or Fab-Fd genes from common phage display systems can be directly inserted into one of the cassette vectors through in-frame cloning sites. This design of a single cassette vector combining heavy and light chain expression elements allowed rapid production and secretion of correctly processed and assembled intact immunoglobulins from recombinant baculovirus infected insect cells. The recombinant antibodies showed the expected molecular size of the H2L2 heterodimer in non reducing SDS-PAGE. No apparent differences were found between the expression level of heavy and light chains, and antigen binding function was preserved. For various antibodies, yields between 6 and 18 mg/l IgG were obtained.

[Human Fab antibodies derived from phage display library neutralize hepatitis A virus in vitro]

OBJECTIVE

Development of recombinant human monoclonal antibody to hepatitis A virus as a emergent measure for prevention of hepatitis A virus infection.

METHODS

Human neutralizing monoclonal antibody Fab fragments to HAV have been developed by using phage display technique. The heavy and light chains of human IgG Fab genes were amplified from a HAV patient in convalescent stage. The combinatorial phage antibody library was established by inserting both heavy and light chains of Fab genes into phage mid-vector pComb3 and followed by help phage infection after 4 rounds of panning with purified HAV as coated antigen.

RESULTS

The human Fab fragments to HAV were selected and expressed in bacteria.

CONCLUSIONS

The specific binding of Fab antibodies to HAV were demonstrated by their reaction with HAV antigen in ELISA. These results provide the basis for further development of a neutralizing recombinant human whole IgG molecule and hold promise for future use in the prophylaxis of HAV infection.

Smurf2 is a ubiquitin E3 ligase mediating proteasome-dependent degradation of Smad2 in transforming growth factor-beta signaling

Smads are important intracellular signaling effectors for transforming growth factor-beta (TGF-beta) and related factors. Proper TGF-beta signaling requires precise control of Smad functions. In this study, we have identified a novel HECT class ubiquitin E3 ligase, designated Smurf2, that negatively regulates Smad2 signaling. In both yeast two-hybrid and in vitro binding assays, we found that Smurf2 could interact with receptor-activated Smads (R-Smads), including Smad1, Smad2, and Smad3 but not Smad4. Ectopic expression of Smurf2 was sufficient to reduce the steady-state levels of Smad1 and Smad2 but not Smad3 or Smad4. Significantly, Smurf2 displayed preference to Smad2 as its target for degradation. Furthermore, Smurf2 exhibited higher binding affinity to activated Smad2 upon TGF-beta stimulation. The ability of Smurf2 to promote Smad2 destruction required the HECT catalytic activity of Smurf2 and depended on the proteasome-dependent pathway. Consistent with these results, Smurf2 potently reduced the transcriptional activity of Smad2. These data suggest that a ubiquitin/proteasome-dependent mechanism is important for proper regulation of TGF-beta signaling.

Transverse asymmetry AT' from the quasielastic 3He(e,e') process and the neutron magnetic form factor

We have measured the transverse asymmetry A(T') in 3He(e,e(')) quasielastic scattering in Hall A at Jefferson Laboratory with high precision for Q2 values from 0.1 to 0.6 (GeV/c)(2). The neutron magnetic form factor G(n)(M) was extracted based on Faddeev calculations for Q2 = 0.1 and 0.2 (GeV/c)(2) with an experimental uncertainty of less than 2%.

Mechanisms underlying induction of heme oxygenase-1 by nitric oxide in renal tubular epithelial cells

We examined whether nitric oxide-generating agents influence expression of heme oxygenase-1 (HO-1) in renal proximal tubular epithelial cells, LLC-PK(1) cells, and the mechanisms underlying any such effects. In sublytic amounts, the nitric oxide donor sodium nitroprusside induced HO-1 mRNA and protein and HO activity in a dose-dependent and time-dependent fashion; this induction was specific for nitric oxide since the nitric oxide scavenger carboxy-2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide significantly reduced such induction. The induction of HO activity by sodium nitroprusside, or by another nitric oxide donor, spermine NONOate, was markedly reduced by the iron chelator deferoxamine. Two different thiol-containing agents, N-acetylcysteine and dithiothreitol, blunted such induction of HO by nitric oxide. Downstream products of nitric oxide, such as peroxynitrite or cGMP, were not involved in inducing HO. In higher concentrations (millimolar amounts), sodium nitroprusside induced appreciable cytotoxicity as assessed by lactate dehydrogenase (LDH) release and lipid peroxidation, and both of these effects were markedly reduced by deferoxamine. Inhibition of HO did not affect the cytotoxic effects (measured by LDH release) of sodium nitroprusside. We thus provide the novel description of the induction of HO-1 in renal proximal tubular epithelial cells exposed to nitric oxide donors and provide the first demonstration in kidney-derived cells for the involvement of a redox-based mechanism in such expression. We also demonstrate that, in LLC-PK(1) cells exposed to nitric oxide donors, chelatable iron is involved in eliciting the HO-1 response observed at lower concentrations of these donors, and in mediating the cytotoxic effects of these donors when present in higher concentrations.

Identification and characterization of a potent, selective, and orally active antagonist of the CC chemokine receptor-1

The CC chemokine receptor-1 (CCR1) is a prime therapeutic target for treating autoimmune diseases. Through high capacity screening followed by chemical optimization, we identified a novel non-peptide CCR1 antagonist, R-N-[5-chloro-2-[2-[4-[(4-fluorophenyl)methyl]-2-methyl-1-piperazinyl ]-2-oxoethoxy]phenyl]urea hydrochloric acid salt (BX 471). Competition binding studies revealed that BX 471 was able to displace the CCR1 ligands macrophage inflammatory protein-1alpha (MIP-1alpha), RANTES, and monocyte chemotactic protein-3 (MCP-3) with high affinity (K(i) ranged from 1 nm to 5.5 nm). BX 471 was a potent functional antagonist based on its ability to inhibit a number of CCR1-mediated effects including Ca(2+) mobilization, increase in extracellular acidification rate, CD11b expression, and leukocyte migration. BX 471 demonstrated a greater than 10,000-fold selectivity for CCR1 compared with 28 G-protein-coupled receptors. Pharmacokinetic studies demonstrated that BX 471 was orally active with a bioavailability of 60% in dogs. Furthermore, BX 471 effectively reduces disease in a rat experimental allergic encephalomyelitis model of multiple sclerosis. This study is the first to demonstrate that a non-peptide chemokine receptor antagonist is efficacious in an animal model of an autoimmune disease. In summary, we have identified a potent, selective, and orally available CCR1 antagonist that may be useful in the treatment of chronic inflammatory diseases.

ADP-Ribosyl cyclase in rat vascular smooth muscle cells: properties and regulation

We investigated whether ADP-ribosyl cyclase (ADPR-cyclase) in rat vascular smooth muscle cells (VSMCs) has enzymatic properties that differ from the well-characterized CD38-antigen ADPR-cyclase, expressed in HL-60 cells. ADPR-cyclase from VSMCs, but not CD38 ADPR-cyclase from HL-60 cells, was inhibited by gangliosides (10 micromol/L) GT(1B), GD(1), and GM(3). Preincubation of membranes from CD38 HL-60 cells, but not from VSMCs, with anti-CD38 antibodies increased ADPR-cyclase activity; CD38 antigen was detected both in VSMCs and in HL-60 cells. ADPR-cyclase in VSMC membranes was more sensitive than CD38 HL-60 ADPR-cyclase to inactivation by N-endoglycosidase F and to thermal inactivation at 45 degrees C. The specific activity of ADPR-cyclase in membranes from VSMCs was >20-fold higher than in membranes from CD38 HL-60 cells. Most importantly, VSMC ADPR-cyclase was inhibited by Zn(2+) and Cu(2+) ions; the inhibition by Zn(2+) was dose dependent, noncompetitive, and reversible by EDTA. In contrast, Zn(2+) stimulated the activity of CD38 HL-60 ADPR-cyclase and other known types of ADPR-cyclases. Retinoids act either via the nuclear receptor retinoic acid receptor or retinoid X receptor, including all-trans retinoic acid (atRA), and panagonist 9-cis-retinoic acid-upregulated VSMC ADPR-cyclase; the stimulatory effect of atRA was blocked by actinomycin D and cycloheximide. 1,25(OH)(2)-Vitamin D(3) (calciferol) stimulated VSMC ADPR-cyclase dose dependently at subnanomolar concentrations (ED(50) congruent with 56 pmol/L). Oral administration of atRA to rats resulted in an increase of ADPR-cyclase activity in aorta ( congruent with+60%) and, to a lesser degree, in myocardium of left ventricle (+18%), but atRA had no effect on ADPR-cyclases in lungs, spleen, intestinal smooth muscle, skeletal muscle, liver, or testis. Administration of 3,5,3'-triiodothyronine (T(3)) to rats resulted in an increase of ADPR-cyclase activity in aorta ( congruent with+89%), but not in liver or brain. We conclude the following: (1) ADPR-cyclase in VSMCs has enzymatic properties distinct from "classic" CD38 ADPR-cyclase, especially sensitivity to inhibition by Zn(2+) and Cu(2+); (2) ADPR-cyclase in VSMCs is upregulated by various retinoids, calcitriol, and T(3) in vitro; and (3) administration of atRA and T(3) increases ADPR-cyclase in aorta in vivo. We suggest that the cADPR signaling system plays an important role in the regulation of VSMC functions in response to steroid superfamily hormones.

[The partial nucleotide sequence of L segment of Hantavirus strain]

OBJECTIVE

To study the nucleotide sequence of L segment of Hantavirus strain A9.

METHODS

The partial L segment cDNA of A9 strain was amplified by PCR, the PCR product was sequenced.

RESULTS

The nucleotide sequence of partial L segment of A9 strain was provided, the sequence was A, T rich, similar to other Hantaviruses, and similar to both M, S segments. Compared with nucleotide sequences from other Hantaviruses, it revealed a higher homology to HTN virus strain 76-118,83.5% at nucleotide level and 96.7% at deduced amino level. SNV, PUU and Tula viruses shared the lower homology. A9 and 76-118 were at same cluster in phylogenetic analysis, close to SEO virus but not to PUU, SNV, Tula viruses. Comparing of partial nucleotide sequence of strain A9 with 76-118, some conserved regions were found, but also some regions of A9 were more conserved to other viruses not 76-118. It suggested that when design the primers for L segments amplification, more than one type of Hantavirus sequence should he concerned. Like the homology from M and S segments of Hantaviruses, the viruses isolated from same host animal showed high homology.

CONCLUSIONS

Nucleotide sequence of L segment of Hantavirus strain A9 revealed homology between 85.2% -70.8% to different types of Hantavirus and shared a higher homology of 85.2% to strain 76-118.

[Detection of IgG antibody to hepatitis G virus by ELISA]

OBJECTIVE

To study the relation of HGV IgG antibody (anti- HGV IgG) to various viral infections, ALT and HGV RNA.

METHODS

To detect anti-HGV IgG from 315 persons infected with various viruses hepatitis (A - E) and 117 healthy blood donors by ELISA. The detection of ALT of these peoples, and detect HGV RNA of the samples of positive anti-HGV IgG by RT-PCR were also carried out.

RESULTS

The positive rate of anti-HGV IgG of 117 blood donors was 3.42% (4/117), and that of the people infected by non A- E, HAV, HBV, HCV, HEV, HBV and HCV, HBV and HDV, HBV and HEV were 5.95%(5/84), 0(0/3), 3.75% (3/80), 17. 28%(14/81), 0(0/15), 33.33%(5/15), 3.33%(1/30), 16.66%(1/6), respectively. The relativity of anti-HGV IgG and HGV RNA was 30.30% (10/33), and 33.33% of ALT level in the antibody positive samples were elevated.

CONCLUSIONS

HGV may infect people alone, or coinfect with HBV or /and HCV, but is highly relative to HCV, and the coinfection of HGV with HCV may increase the degree of liver damage.

[Generation of monoclonal antibody Fab fragments to parathyroid hormone related protein by phage display technology]

OBJECTIVE

To develop monoclonal antibody Fab fragments using display technique.

METHODS

The mouse IgG Fab genes of heavy and light chains were amplified from spleen cells of a parathyroid hormone-related protein (PTHrP) immunized mouse. The combinatorial phage antibody library was prepared by inserting both heavy and light chain Fab genes into phagemid vector pComb3 and followed by infection of helper phage. The library was selected by purified recombinant PTHrP.

RESULTS

The combinatorial phage antibody library was constructed successfully and the specific mouse Fabs to PThrP were selected and expressed in E. coli.

CONCLUSIONS

The selected specific mouse Fabs can recognize PTHrP with high specificity.

Production and functional roles of nitric oxide in the proximal tubule

A significant role for nitric oxide (NO) in proximal tubule physiology and pathophysiology has been revealed by a series of in vivo and in vitro studies. Whether the proximal tubule produces NO under basal conditions is still controversial; however, evidence suggests that the proximal tubule is constantly exposed to NO that might include NO from nonproximal tubule sources. When challenged with a variety of stimuli, including hypoxia, the proximal tubule is able to produce large quantities of NO. In vivo studies generally indicate that NO inhibits fluid and sodium reabsorption by the proximal tubule. However, the final effect of NO on proximal tubular reabsorption appears to depend on the concentration of NO and involve interaction with other regulatory mechanisms. NO regulates Na(+)-K(+)-ATPase, Na(+)/H(+) exchangers, and paracellular permeability of proximal tubular cells, which may contribute to its effect on proximal tubular transport. Enhanced production of NO, perhaps depending on macrophage type inducible NO synthase, participates in hypoxic/ischemic proximal tubular injury. In conclusion, NO plays a fundamental role in both physiology and pathophysiology of the proximal tubule.

Species selectivity of a small molecule antagonist for the CCR1 chemokine receptor

The species specificity of a small molecule antagonist for the human CCR1 chemokine receptor, 2-2-diphenyl-5-(4-chlorophenyl)piperidin-1-yl)valeronitrile (CCR1 antagonist 1), has been examined using cloned CCR1 receptors from various species. The compound was able to bind to rabbit, marmoset, and human CCR1, and was able to block the functional activation of these receptors. However, it failed to significantly displace radiolabeled macrophage inflammatory protein-1alpha (MIP-1alpha) binding to mouse CCR1 at concentrations up to 10 microM. These data suggested that the antagonist binding site is well-conserved in rabbit, marmoset and human CCR1, but not in mouse CCR1. The functional selectivity and mechanism of action for CCR1 antagonist 1 were further characterized. CCR1 antagonist 1 blocked the increase in intracellular Ca(2+) stimulated by CCR1 agonists, but had no effect on N-formyl-Met-Leu-Phe (FMLP), monocyte chemotactic protein-1 (MCP-1) and stromal-derived factor 1alpha (SDF1alpha)-induced Ca(2+) mobilization, demonstrating functional selectivity for CCR1. Since CCR1 antagonist 1 is a functional antagonist of marmoset and rabbit CCR1 receptors, it should be possible to test its efficacy in animal models of disease.

Partial rescue of the ocular retardation phenotype by genetic modifiers

The or(J) allele of the murine ocular retardation mutation is caused by a premature stop codon in the homeodomain of the Chx10 gene. When expressed on an inbred 129/Sv strain, the or(J) phenotype is characterized by microphthalmia and a thin, poorly differentiated retina in which the peripheral portion is affected to a greater extent than the central portion. Such mutant retinae lack differentiated bipolar cells and the optic nerve typically fails to form, leading to blindness. Here, we show that progeny from an outcrossed backcross between 129/Sv-or(J) /or(J) and Mus musculus castaneus produce animals that are homozygous for the or(J) mutation and exhibit a much ameliorated eye phenotype. Although not of normal size, such modified or(J) eyes are significantly larger than those in 129/Sv-or(J) /or(J) mice, and contain a better organized retina which includes bipolar cells. Furthermore, optic nerves are frequently present, and the eyes show a degree of function as reflected by electroretinogram and pupillary response. As in 129/Sv-or(J) /or(J) mice, however, modified or(J) eyes show incomplete growth and a lack of cell differentiation in the periphery of the retina. The selective, and apparently nonmodifiable, effect of the ocular retardation phenotype on the periphery of the retina indicates that Chx10 plays an important role in the central-to-peripheral gradient of retinal development. These findings demonstrate that the ocular retardation phenotype can be greatly modified by the genetic background, and help to define a role for Chx10 in ocular development.

Nitric oxide activates PKCalpha and inhibits Na+-K+-ATPase in opossum kidney cells

Nitric oxide (NO) reduces the molecular activity of Na+-K+-ATPase in opossum kidney (OK) cells, a proximal tubule cell line. In the present study, we investigated the cellular mechanisms for the inhibitory effect of NO on Na+-K+-ATPase. Sodium nitroprusside (SNP), a NO donor, inhibited Na+-K+-ATPase in OK cells, but not in LLC-PK1 cells, another proximal tubule cell line. Similarly, phorbol 12-myristate 13-acetate, a protein kinase C (PKC) activator, inhibited Na+-K+-ATPase in OK, but not in LLC-PK1, cells. PKC inhibitors staurosporine or calphostin C, but not the protein kinase G inhibitor KT-5823, abolished the inhibitory effect of NO on Na+-K+-ATPase in OK cells. Immunoblotting demonstrated that treatment with NO donors caused significant translocation of PKCalpha from cytosolic to particulate fractions in OK, but not in LLC-PK1, cells. Furthermore, the translocation of PKCalpha in OK cells was attenuated by either the phospholipase C inhibitor U-73122 or the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one. U-73122 also blunted the inhibitory effect of SNP on Na+-K+-ATPase in OK cells. The phospholipase A2 inhibitor AACOCF3 did not blunt the inhibitory effect of SNP on Na+-K+-ATPase in OK cells. AACOCF3 alone, however, also decreased Na+-K+-ATPase activity in OK cells. In conclusion, our results demonstrate that NO activates PKCalpha in OK, but not in LLC-PK1, cells. The activation of PKCalpha in OK cells by NO is associated with inhibition of Na+-K+-ATPase.

[Simultaneous determination of norepinephrine and epinephrime in plasma by using high performance liquid chromatograph]

A sensitive and rapid method was reported for the determination of nerepinephrine (NE) and epinephrine (E) in plasma by using high-performance liquid chromatography with an electrochemical detector (HPLC-EC) and YWG-C18 column(5u). 3,4-Dihydroxybenzylamine(DHBA) was used as an internal standard. The mobile phase of 0.05 mol/L actate buffer(pH3.0)-methanol-0.05 mol/L EDTA-Na2(78:20:2) with of 200 mg/L SDS solution was pumped through the column with a flow rate of 1.0 ml/min. The lengths of retention time for NE, E and DHBA(IS) was 7.3 min, 8.3 min and 10.4 min, respectively. The standard curve was linear within the concentration range of 31.25 to 4000 ng/L for NE and E (NE: r = 0.9999 E: r = 0.9996). The within day RSD (%) were less than 1.87% for NE and less than 2.07% for E, inter-day RSD(%) were less than 8.92% for NE and less than 9.65% for E respectively. The average extraction recovery(%) for NE and E were 93.5% +/- 5.50% and 91.3% +/- 1.77% respectively. This method has been applied to the diagnosis of pheochromocytoma and clinical research.

[Determination of 6-methoxy-2-naphthylacetic acid, a major metabolite of nabumetone, in human plasma by HPLC]

This paper reports a sensitive and rapid method for determining 6-methoxy-2-naphthylacetic acid (MNA), a major metabolite of nabumetone in human plasma using naproxen as the internal standard. High performance liquid chromatograph model 680 (Waters, USA) with a variable wavelength UV detector and reversed-phase YWG-C18 column (10 microns, 250 x 4.6 mm) was used. After the addition of acetate buffer(pH3.0), the plasma sample was extracted with methylene chloride. The mobile phase of methanol-pH3.0, 0.02 mol/L acetate buffer(74:26) was pumped at 1.0 ml/min through the column. The detector at 0.01AUFS was set at 270 nm. The retention times for MNA and naproxen were 3.98 min and 4.73 min respectively. Standard curve was linear in the concentration range of 0.5 to 64 mg/L. The detection limit in serum was 0.02 mg/L. Extraction recovery was 88%-94%; method recovery 96%-102%; withinday RSD less than 3.5%; inter-day RSD less than 5%.

The paracellular permeability of opossum kidney cells, a proximal tubule cell line

The paracellular permeability of opossum kidney cells, a proximal tubule cell line.

BACKGROUND

The regulation of the unusually leaky paracellular pathway of the proximal tubule is poorly understood partially because of the lack of an appropriate in vitro cell model. In this study, we determined whether the paracellular permeability of opossum kidney (OK) cells would resemble that of the in vivo proximal tubule epithelium.

METHODS

The parental and subclonal OK cells and, for comparison, LLC-PK1 cells were cultured on permeable Transwell supports. The apparent paracellular permeability coefficient (Papp) for the extracellular marker 3H-mannitol was determined.

RESULTS

The Papp of OK cell sheets (12.17 x10-6 cm/sec) was remarkably close to the previously reported Papp of rat proximal tubules. The Papp of LLC-PK1 cells, another proximal tubule cell line, however, was approximately 20-fold lower than that of both OK cells and the in vivo proximal tubule. Phorbol 12-myristate 13-acetate, a protein kinase C activator, enhanced the Papp of OK cell sheets. The characteristic response of paracellular permeability to Ca2+ switch was demonstrated in OK cell sheets. Slight variations of Papp among several OK subclones were observed. Basal to apical Papp was uniformly higher than apical to basal Papp, independent of cell subtype. This rectification was attenuated by inhibition of active transport.

CONCLUSIONS

OK cell sheets cultured on Transwell supports possess a leaky paracellular pathway resembling that of the proximal tubule epithelium in vivo.

Synthesis of NAADP and cADPR in mitochondria

Here we investigated whether cADPR and NAADP are synthesized in mitochondria. We found that ADPR-cyclase activity is present in mitochondria. In addition, we describe for the first time synthesis of NAADP in this intracellular organelle. ADPR-cyclase activities (V(MAX)) and NAADP synthesis in mitochondria were about 4-fold lower than that in plasma membranes. Otherwise, ADPR-cyclases in mitochondria and in plasma membranes have similar catalytic properties in terms of apparent K(m) for the substrate NGD and K(i) values for inhibition by dithiotreitol, beta-NAD, and nicotinamide. ADPR-cyclase in plasma membranes and to a lesser degree mitochondrial enzyme, was inhibited by Zn(2+) and Cu(2+); ADPR-cyclase from mitochondria was more stable upon thermal inactivation. CD38 antigen, determined by Western blot, was well-expressed in plasma membranes but was far less so (17-fold less) in mitochondria. The major difference between ADPR-cyclase activity in mitochondria and plasma membranes is that mitochondrial cyclase activity was increased by incubation with nonionic detergents. Conversely, the incubation with phosphatidylinositol-specific phosphodiesterase C (PI-PLC) released ADPR-cyclase activity from plasma membranes, but not from mitochondria. We conclude that ADPR-cyclase in mitochondria and in plasma membranes are both multifunctional enzymes with similar catalytic properties; however, the two ADPR-cyclases differ in the mode of anchoring to the membrane: by glycosylphosphoinositol anchor in plasma membranes and by hydrophobic interactions in mitochondria. In addition, synthesis of NAADP can also be found in intracellular organelles via mitochondria. We propose that independent mitochondrial cADPR and NAADP systems may have an intracrine signaling function that is not dependent on direct input by extracellular hormonal stimuli, but rather responds to changes of intermediary cellular metabolism.

Discovery of novel non-peptide CCR1 receptor antagonists

Ligands for the CCR1 receptor (MIP-1alpha and RANTES) have been implicated in a number of chronic inflammatory diseases, most notably multiple sclerosis and rheumatoid arthritis. Because these ligands share a common receptor, CCR1, we sought to discover antagonists for this receptor as an approach to treating these disorders. A novel series of 4-hydroxypiperidines has been discovered by high throughput screening (HTS) which potently inhibits the binding of MIP-1alpha and RANTES to the recombinant human CCR1 chemokine receptor. The structure-activity relationships of various segments of this template are described as the initial HTS lead 1 was optimized synthetically to the highly potent receptor antagonist 6s. This compound has been shown to have at least 200-fold selectivity for inhibition of CCR1 over other human 7-TM receptors, including other chemokine receptors. In addition, data obtained from in vitro functional assays demonstrate the functional antagonism of compound 6s and structurally related analogues against the CCR1 receptor in a concentration dependent manner. The discovery and optimization of potent and selective CCR1 receptor antagonists represented by compound 6s potentially represent a novel approach to the treatment of chronic inflammatory diseases.

Nitric oxide reduces the molecular activity of Na+,K+-ATPase in opossum kidney cells

BACKGROUND

Nitric oxide (NO) directly inhibits fluid and solute reabsorption in the proximal tubule. In the present study, we investigated the effect of NO on the Na+, K+-ATPase of opossum kidney (OK) cells, a proximal tubule cell line, and its mechanisms.

METHODS

Na+,K+-ATPase activity in the membrane fraction of OK cells was measured as the ouabain-sensitive ATP hydrolytic activity. The enzyme unit number on intact cells was measured by ouabain-binding assay.

RESULTS

Incubation with 0.5 mM sodium nitroprusside (SNP), a NO donor, for two hours inhibited the catalytic activity of the membrane-associated Na+,K+-ATPase in OK cells to 65.5 +/- 9.7% of control (N = 6, P < 0.05 vs. control). This effect of SNP was concentration- and time-dependent. The NO scavenger hemoglobin blunted, while another NO donor spermine NONOate (5 microM) mimicked this effect of SNP. At all concentrations and time points tested, SNP did not alter the molecular number of Na+,K+-ATPase on intact OK cells, indicating that NO inhibited the molecular activity of Na+,K+-ATPase. The soluble guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo-[4, 3-a]quinoxalin-1-one (ODQ), blunted the inhibitory effect of SNP on the Na+,K+-ATPase activity. An exogenous cGMP analog similarly inhibited the Na+,K+-ATPase activity. Neither lipid soluble antioxidants vitamin E/probucol or thiol group compound DL-dithiothreitol (DTT) altered the inhibitory effect of SNP on the Na+,K+-ATPase activity.

CONCLUSIONS

NO inhibited the molecular activity of the Na+,K+-ATPase of the OK proximal tubule cell line probably via cGMP-dependent mechanisms.

Nitric oxide enhances paracellular permeability of opossum kidney cells

BACKGROUND

Nitric oxide (NO) has been shown to be a paracrine/autocrine regulator of proximal tubular transport. In this study, we investigated the effect of NO on the paracellular permeability of opossum kidney (OK) cells, a proximal tubule cell line that possesses a leaky paracellular pathway resembling that of the in vivo proximal tubule.

METHODS

Paracellular permeability of OK cells cultured on permeable supports was measured as the apparent paracellular permeability coefficient (Papp) for 3[H]-D-mannitol. Changes in cell viability, cellular adenosine triphosphate (ATP) content, cGMP levels, and lipid peroxidation were assessed.

RESULTS

Incubation with 2 mM sodium nitroprusside (SNP), an NO donor, for 24 hours significantly enhanced the Papp of OK cell sheets by 30.6 +/- 7.0% (N = 8, P < 0.05). This effect was largely blunted by hemoglobin, a NO scavenger. Cell viability was not compromised. This effect of SNP was concomitant with a moderate reduction of cellular ATP content, an increase in lipid peroxidation, and an increase in cellular cGMP levels. The antioxidant superoxide dismutase (SOD) significantly attenuated the effect of SNP on cellular ATP content and blunted the increase in Papp caused by SNP. A soluble guanylate cyclase inhibitor did not affect the effect of SNP on the Papp.

CONCLUSIONS

NO enhances the paracellular permeability of OK cells possibly via mechanisms involving decreases in cellular ATP content.

[Study on chromatographic peak identification by means of peak shape analysis]

A new method for chromatographic peak identification by means of peak shape analysis is presented in this paper. Directly measurable parameters, i.e. peak width and asymmetry factor are first utilized for peak shape analysis. It is showed from theoretical and experimental results that for a component having almost the same retention time with the standard, an overlapped peak can be obtained by injecting the mixture of analyte and standard. In comparing the peak shape of overlapped peak with the standard one, the component can be identified whether it is the same with the standard or not.

Differential effect of pH upon cyclic-ADP-ribose and nicotinate-adenine dinucleotide phosphate-induced Ca2+ release systems

We investigated the pH dependence and the effects of thimerosal and dithiothreitol (DTT) upon the Ca2+ release induced by cADP-ribose (cADPR) and nicotinate-adenine dinucleotide phosphate (NAADP) in sea urchin egg homogenates. Both Ca2+ release triggered by cADPR and the binding of [3H]cADPR to sea urchin egg homogenates were decreased by alkalization of the assay media from pH 7.2 to 8.9. In contrast, NAADP-triggered Ca2+ release was not influenced by changes in pH. The Ca2+ release induced by cADPR was potentiated by thimerosal and inhibited by DTT, but neither thimerosal nor DTT had any effect upon the Ca2+ release induced by NAADP. We conclude that cADPR-sensitive Ca2+-release mechanisms are dependent on pH of the assay media and are sensitive to thiol group modification. On the other hand, these functional properties are not shared by NAADP-regulated Ca2+ channels.

[Effect of ischemia/reperfusion in cardiac surgery with cardiopulmonary bypass on nitric oxide levels of peripheral blood in patients]

To examine the effect of ischemia/reperfusion in cardiac surgery with cardiopulmonary bypass (CPB) on nitric oxide (NO) levels of peripheral blood, venous levels of NO2- and NO3- were measured at multiple time-points before, during, and after CPB by means of high-pressure liquid chromatograph to reflect NO concentration indirectly in 20 patients. The results showed there was a linear regression between the decreased trend of NO release at the period of peri-CPB is related to the endothelial cell activation caused by ischemia/reperfusion at the same time. Therefore it is necessary to explore the regulation and action of NO release during systemic inflammatory response procedure in CPB.

Nucleotide sequence and phylogenetic analysis of the medium (M) genomic RNA segments of three hantaviruses isolated in China

The medium (M) genome segment of hantaviruses (family Bunyaviridae) encodes the two virion glycoproteins. G1 and G2, as a precursor protein in the complementary sense RNA. We determined the nucleotide sequences of the M genome segments of three Chinese hantavirus isolates, a Hantaan-type (HTN) virus designated A9 and two Seoul-type (SEO) viruses designated L99 and HB55, and compared them to those of other HTN or SEO viruses isolated in Eastern Asia. The M segment of A9 is 3616 nucleotides in length and shows 99.5% identity at the nucleotide level and 99.1% identity at the amino acid level to that of the Chinese HTN isolate HV114. The M segments of L99 and HB55 are 3652 nucleotides in length, one nucleotide longer than the M segments of other sequenced SEO isolates such as SEO 80-39, SR-11, and Biken-1. The Chinese SEO isolates showed 95% nucleotide sequence identity and 99% amino acid sequence identity to SEO 80-39. We also sequenced a 736 nucleotides region of the M genome segment of another Chinese SEO isolate, R22, which revealed errors in the published data. Phylogenetic analysis of the available sequences indicated that both the Chinese HTN- and SEO-type viruses form lineages distinct from those of the isolates from other parts of Eastern Asia.

Phosphorylation and functional desensitization of the alpha2A-adrenergic receptor by protein kinase C

We have investigated the potential for protein kinase C (PKC) to phosphorylate and desensitize the alpha2A-adrenergic receptor (alpha2AAR). In whole-cell phosphorylation studies, recombinantly expressed human alpha2AAR displayed an increase in phosphorylation after short-term exposure to 100 nM phorbol 12-myristate-13-acetate (PMA) that was blocked by preincubation with a PKC inhibitor. This increase in receptor phosphorylation over basal amounted to 172 +/- 40% in COS-7 cells and 201 +/- 40% in Chinese hamster ovary cells. In permanently transfected Chinese hamster fibroblast cells, PKC activation by brief exposure of the cells to PMA resulted in a marked desensitization of alpha2AAR function, amounting to a 68 +/- 4% decrease in the maximal agonist (UK14304)-stimulated intracellular calcium release. Such desensitization was blocked by the PKC inhibitor bisindolylmaleimide I and was not evoked by an inactive phorbol ester. The desensitization of this agonist response was not caused by PKC-mediated augmentation of G protein-coupled receptor kinase activity, because PMA-promoted desensitization of a mutated alpha2AAR that lacked G protein-coupled receptor kinase phosphorylation sites was identical to that of wild-type alpha2AAR. To test whether PKC phosphorylation is a mechanism by which alpha2AAR can be regulated by other receptors, the alpha1bAR was co-expressed with the alpha2AAR in Chinese hamster ovary cells. Upon selective activation of alpha1bAR, the function of alpha2AAR underwent a 53 +/- 5% desensitization. Thus, cellular events that result in PKC activation promote phosphorylation of the alpha2AAR and lead to substantial desensitization of receptor function. This heterologous regulation also represents a mechanism by which rapid crosstalk between the alpha2AAR and other receptors can occur.

[Chemosensitivity test for head and neck cancers]

The chemosensitivities of 27 fresh specimens of head and neck cancers were tested with MTT assay to study the practicability and accuracy of the assay for the examination of chemosensitivity in head and neck cancer patients. The chemosensitivities among cancers of different primary sites, pathologic types, histological differentiations, DNA ploidies and estrogen receptors were compared in an attempt to evaluate the choice of anticancer drugs for individual chemotherapy. Eight anticancer drugs: Methotroxate (MTX), Mitomycin C (MMC), fluorouracil (5-Fu), Carboplatin (CBDCA), Pingyangmycin (PYM), Homoharringtonine (HHA), Etoposid (VP16) and Vincristine (VCR) were included. The success rate of MTT assay in the present study was 92.6% and the accuracy was relatively high. The sensitivity sequence was PYM > HHA > MTX > CBDCA > MMC > 5-Fu > VCR > VP16, which suggested HHA should be recommended first to the chemotherapy of head and neck cancer. No chemosensitivity differences were found among different primary sites histological differentiations and estrogen receptors. The chemosensitivity of squamous cell carcinoma was significantly higher than that of adenoid cystic carcinoma. The chemosensitivity of aneuploid tumor was significantly higher than that of diploid.

Identification and characterization of small molecule functional antagonists of the CCR1 chemokine receptor

The CC chemokines macrophage inflammatory protein-1alpha (MIP-1alpha) and RANTES (regulated on activation normal T cell expressed) have been implicated in rheumatoid arthritis and multiple sclerosis. Since their effects are mediated through the CCR1 chemokine receptor, we set up a small molecule CCR1 antagonist program to search for inhibitors. Through high capacity screening we discovered a number of 4-hydroxypiperidine compounds with CCR1 antagonist activity and report their synthesis and in vitro pharmacology here. Scatchard analysis of the competition binding data revealed that the compounds had Ki values ranging from 40 to 4000 nM. The pharmacological profile of the most potent member of this series, compound 1 (2-2-diphenyl-5-(4-chlorophenyl)piperidin-lyl)valeronitri te), was further evaluated. Compound 1 showed concentration-dependent inhibition of MIP-1alpha-induced extracellular acidification and Ca2+ mobilization demonstrating functional antagonism. When given alone, the compound did not elicit any responses, indicating the absence of intrinsic agonist activity. Compound 1 inhibited MIP-1alpha- and RANTES-induced migration in peripheral blood mononuclear cells in a dose-responsive manner. Selectivity testing against a panel of seven transmembrane domain receptors indicated that compound 1 is inactive on a number of receptors at concentrations up to 10 microM. This is the first description of CCR1 receptor antagonists that may be useful in the treatment of chronic inflammatory diseases involving MIP-1alpha, RANTES, and CCR1.

Identification and characterization of the CXCR4 chemokine receptor in human T cell lines: ligand binding, biological activity, and HIV-1 infectivity

The CXCR4 chemokine receptor has been shown to respond to the C-X-C chemokine stromal-derived factor (SDF-1) and has recently been shown to be an important coreceptor for HIV-1 infection. In the present paper we have tested a number of human lymphocyte cell lines, including Jurkat, HUT78, CEM, and Sup-T1 for the presence of CXCR4 receptors. We found that these T cell lines bind SDF-1alpha and SDF-1beta with high affinity. The CXCR4 Ab 12G5 inhibited both SDF-1 binding and HIV-1LAI-mediated fusion of CEM. Scatchard analysis revealed the presence of approximately 150,000 SDF-1alpha-binding sites per cell with a Kd between 5 and 10 nM. Cross-competition experiments using unlabeled SDF-1alpha and SDF-1beta revealed that both chemokines are equally capable of displacing their radiolabeled counterparts. Internalization studies with [125]I-SDF-1alpha revealed that Jurkat cells internalized greater than 90% of the ligand by 2 h at 37 degrees C. SDF-1alpha was also chemotactic for Jurkat cells and caused an increase in the rate of extracellular acidification that was half-maximal at 18 nM SDF-1alpha and could be inhibited by pretreatment with the SDF-1 proteins, pertussis toxin, or the Ab 12G5. Finally, SDF-1alpha also caused an increase in the cytosolic Ca2+ concentration in Sup-T1 cells that was abolished by preincubating the cells with pertussis toxin or PMA and inhibited by the Ab 12G5. This molecular characterization of CXCR4 receptors should prove useful in clarifying receptor interaction with SDF-1 proteins and with HIV-1 glycoprotein, with the ultimate aim of targeting the viral interaction for therapeutic intervention.

Effects of removing circulatory tumor necrosis factor by immunoadsorption on experimental endotoxin shock animals

OBJECTIVE

To evaluate the effects of removing circulatory tumor necrosis factor (TNF) by immunoadsorption on endotoxin shock animals.

METHODS

Sixty New Zealand white rabbits were injected intravenously with lethal dose of endotoxin (10 Billion cfu/kg E. Coli endotoxin) and randomly divided into 3 groups: perfusion group, hemoperfusion started at 1 hour after injecting endotoxin through immunoadsorbent columns against TNF; pseudoperfusion group, hemoperfusion through blank columns; and control group, injected with endotoxin only. The arterial pressure, microcirculation of the mesentery, plasma levels of TNF, IL-1, IL-6, IL-8, nitrite, endothelin-1 (ET-1), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine were measured and analyzed and finally the survival rate was observed.

RESULTS

Plasma levels of TNF were sharply reduced after immunoadsorption. Moreover, release of IL-1, IL-6, IL-8, NO and ET-1 were also attenuated. Hemodynamic abnormalities could be improved and survival rate ameliorated significantly.

CONCLUSION

Specific immunoadsorption of circulating TNF might be a new and effective therapy for endotoxin shock.

Baculovirus expression of a human G2-specific, neutralizing IgG monoclonal antibody to Puumala virus

We amplified by polymerase chain reaction the heavy- and light-chain antibody genes of a human hybridoma secreting a neutralizing, IgG monoclonal antibody to the G2 protein of Puumala virus. The heavy- and light-chain genes were cloned and sequenced and the deduced amino acids were aligned with those of other human antibodies to identify the constant and variable regions. The genes were cloned into the baculovirus plasmid transfer vector pACUW51 such that the heavy-chain and light-chain genes were under control of the baculovirus polyhedrin or p10 promoters, respectively. The transfer vector plasmid was cotransfected into cultured Spodoptera frugiperda (Sf9) cells with linearized DNA of the baculovirus Autographa californica nuclear polyhedrosis virus, and recombinant baculoviruses were selected by plaque formation on monolayers of Sf9 cells. Expression and secretion of an IgG monoclonal antibody was confirmed by assay of recombinant-infected Sf9 cell supernatants for the presence of the heavy and light chains. Specificity of the expressed human antibody was determined by immune-precipitation of radiolabeled Puumala virus proteins and by ELISA with Puumala virus-infected cell lysates. Similar quantities of the expressed IgG and the authentic monoclonal antibody neutralized Puumala virus in plaque-reduction neutralization assays. Neither the authentic nor the recombinant antibody could passively protect hamsters from challenge with Puumala virus; however, our results demonstrate the potential of this methodology for production of biologically active neutralizing antibodies.

Simultaneous rapid high-performance liquid chromatographic determination of phenytoin and its prodrug, fosphenytoin in human plasma and ultrafiltrate

A reversed-phase high-performance liquid chromatographic assay for the simultaneous determination of phenytoin and fosphenytoin, a prodrug for phenytoin, in human plasma and plasma ultrafiltrate is described. For plasma, the method involves simple extraction of drugs with diethyl ether and evaporation of solvent, followed by injection of the reconstituted sample onto a reversed-phase C18 column. Plasma ultrafiltrate is injected directly into the HPLC column. Compounds are eluted using an ion-pair mobile phase containing 20% acetonitrile. The eluent is monitored by UV absorbance at 210 nm. The fosphenytoin standard curves are linear in the concentration range 0.4 to 400 microg/ml for plasma and 0.03 to 80 microg/ml for ultrafiltrate. Phenytoin standard curves are linear from 0.08 to 40 microg/ml for plasma and from 0.02 to 5.0 microg/ml for ultrafiltrate. No interferences with the assay procedure were found in drug-free blank plasma or plasma ultrafiltrate. Relative standard deviation for replicate plasma or ultrafiltrate samples was less than 5% at concentrations above the limit of quantitation for both within- and between-run calculations.

Confocal pattern period in multiple-aperture confocal imaging systems with coherent illumination

We have built a programmable multiple-aperture confocal imaging system that uses a spatial light modulator (a Texas Instruments digital micromirror device). Excellent axial resolution and confocal imaging quality have been experimentally demonstrated with this system, even when the distance between adjacent ON pixels is four times the size of the pixel aperture. By contrast, typical pinhole-based systems (e.g., a Nipkow disk) employ an adjacent aperture distance-to-size ratio of 10x . We have achieved improvement over such systems by 6.25x in both light-utilization efficiency and confocal image rate without adding more components and extra processing time.

Lack of corneal toxicity of interferon Alpha-2b administered subconjunctivally after sclerectomy

PURPOSE

To evaluate the corneal toxicity of subconjunctival injection interferon alpha-2b at filtering bleb after sclerectomy in white rabbits.

METHODS

Eight rabbits which had been performed sclerectomy were randomly divided into two groups. Each group consisted of four rabbits. Eight eyes in group 1 were subconjunctivally received interferon alpha-2b 5 x 10(5) IU/0.2 ml into filtering bleb from the edge of the filtering site immediately after operation and every postoperative day. The other eight eyes in group 2 were injected with 0.2 ml normal saline. All of the eyes underwent daily examination by slip-lamp microscopy and direct ophthalmoloscopy. Sodium fluorescein was used to assess corneal epithelial integrity. On day 3, 4, 7 and 14, every two rabbits (group 1 and 2 each, respectively) were killed and removed cornea immediately to take examination of the viability of corneal endothelium by dual staining with typan blue and alizanin red S.

RESULTS

No sign of toxicity in corneal epithelium and endothelium were found following continuously injection interferon alpha-2b at filtering bleb 3-14 days totally for selected doses.

CONCLUSION

Subconjunctivally administered interferon alpha-2b at filtering bleb after glaucoma filtering surgery may be a safe drug-applied method.

[Study on the immune state of patients with laryngeal carcinoma]

The authors have carried out the immunoassay on 68 patients with laryngeal carcinoma in order to investigate the relationship between the occurrence and development of the tumour and the body immune state by using the methods of R1D, APAAP and LDH. The results showed that, in comparison with the normal group, CD3+, CD4+ cell and NK cell activity were much lower (P < 0.01), CD8+ cell slightly increased (P > 0.05). IgG, IgA and IgM were also lower (P < 0.05). It indicates that the lower level of cellular immunity, the descent of the ratio of CD4+/CD8+ and the condition which suppresses the body immune system are the interior factors which make the laryngeal carcinoma happening and developing easily. With the development of tumor, the increase of various suppressor factors and the immune system suppressed further the tumor can spread and shift much more easily.

Pseudorandom phase-only encoding of real-time spatial light modulators

We previously proposed a method of mapping full-complex spatial modulations into phase-only modulations. The Fourier transform of the encoded modulations approximates that of the original complex modulations. The amplitude of each pixel is encoded by the property that the amplitude of a random-phasor sum is reduced corresponding to its standard deviation. Pseudorandom encoding is designed for phase-only spatial light modulators that produce 360° phase shifts. Because such devices are rare, experiments are performed with a 326°modulator composed of two In Focus model TVT6000 liquid-crystal displays. Qualitative agreement with theory is achieved despite several nonideal properties of the modulator.

Phase I and pharmacologic study of 9-aminocamptothecin given by 72-hour infusion in adult cancer patients

PURPOSE

To conduct a phase I and pharmacologic study of the new topoisomerase I inhibitor, 9-aminocamptothecin (9-AC).

PATIENTS AND MATERIALS

A 72-hour infusion of 9-AC was administered every 14 days to 48 solid-tumor patients at doses of 5 to 59 microg/m2/h without granulocyte colony-stimulating factor (G-CSF) and 47 to 74 microg/m2/h with G-CSF.

RESULTS

Without G-CSF, two of eight patients who received 47 microg/m2/h had dose-limiting neutropenia in their initial cycle, as did both patients who received 59 microg/m2/h (with a platelet count < 25,000/microL in one). With G-CSF, zero of seven patients treated with 47 microg/m2/h had dose-limiting neutropenia in their first cycle, while dose-limiting neutropenia occurred in six of 14 patients (with platelet count < 25,000/microL in five) entered at 59 microg/m2/h. Among 39 patients entered at > or = 25 microg/m2/h 9-AC with or without G-CSF, fatigue, diarrhea, and nausea/vomiting of grade 2 severity ultimately occurred in 54%, 30%, and 38%, respectively, while grade 3 toxicities of each type occurred in 8% of patients. Steady-state 9-AC lactone concentration (Css) increased linearly from 0.89 to 10.6 nmol/L, and correlated strongly with leukopenia ( r = .85).

CONCLUSION

The recommended phase II dose of 9-AC given by 72-hour infusion every 2 weeks is 35 microg/m2/h without G-CSF or 47 microg/m2/h with G-CSF support. Dose escalation in individual patients may be possible according to their tolerance.

The development and initial validation of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for systemic lupus erythematosus

OBJECTIVE

To develop and perform an initial validation of a damage index for systemic lupus erythematosus (SLE).

METHODS

A list of items considered to reflect damage in SLE was generated through a nominal group process. A consensus as to which items to be included in an index was reached, together with rules for ascertainment. Each center submitted 2 assessments, 5 years apart, on 2 patients with active and 2 with inactive disease, of whom 1 had increased damage and the other had stable disease. Analysis of variance was used to test the factors physician, time, amount of damage, and activity status.

RESULTS

Nineteen physicians completed the damage index on 42 case scenarios. The analysis revealed that the damage index could identify changes in damage seen in patients with both active and inactive disease. Patients who had active disease at both time points had a higher increase in damage. There was good agreement among the physicians on the assessment of damage in these patients.

CONCLUSION

This damage index for SLE records damage occurring in patients with SLE regardless of its cause. The index was demonstrated to have content, face, criterion, and discriminant validity.

Gastrin-releasing peptide receptor signaling resulting in growth inhibition

We demonstrate that gastrin-releasing peptide (GRP) can inhibit the proliferation of human immortal nontumorigenic (184-B5) mammary epithelial cells ectopically expressing the human GRP receptor. Growth of Balb 3T3 cells ectopically expressing relatively high levels of the GRP receptor was also inhibited by GRP; however, growth of transfectants expressing lower levels of the receptor was not inhibited. Compared with Balb 3T3 cells, mammary epithelial cells could be rendered sensitive to growth inhibition by GRP by the expression of fewer GRP receptors. GRP also stimulated DNA synthesis in quiescent, serum-starved Balb 3T3 transfectants. In clones that were sensitive to growth inhibition by GRP by virtue of their expression of relatively high levels of the GRP receptor, the dose-response curve of GRP-stimulated DNA synthesis was bell shaped. This is consistent with our conclusion that the growth-inhibiting activity of GRP required the activation of a relatively large pool of receptors in Balb 3T3 cells. Significantly, prostaglandin H synthase inhibitors, which block the production of prostaglandins from arachidonic acid, reduced GRP-inhibitory effects on DNA synthesis. We also compared a number of GRP-stimulated signaling pathways in Balb 3T3 clones that were sensitive or insensitive to growth inhibition by GRP, including cAMP formation, phospholipase C activation, calcium mobilization, and arachidonic acid formation. Taken together, these results demonstrate a novel GRP receptor-coupled signal pathway promoting growth inhibition in which prostaglandin H synthase plays a significant role.

[Determination of metronidazole in serum by HPLC]

This paper report a sensitive and rapid method for the determination of metronidazole (MTZ) using theophylline as the internal standard. High performance liquid chromatograph model 344 (Beckman) with a 254 nm wavelength UV detector and YWG-C18H37 column (10 microns, 250 x 4.6 mm) was used. To the serum sample 200 microliters, 100 microliters phosphate buffer (0.8 mol/L, pH 7.5) was added, then extracted with 3 ml chloroform containing 5% isopropyl alcohol. The organic layer was removed and evaporated to dryness under an air stream in a 40 degrees C water bath. The residue was dissolved in 30 microliters mobile phase and 20 microliters injected. The mobile phase of water-methanol (73:27) was pumped at 1.0 ml/min through the column. The detector operated at 0.005 aufs. The retention times for MTZ and theophylline were 5.78 and 6.81 min respectively. Standard curve was linear in the concentration range of 0.3125 to 20 mg/L. The detection limit in serum was 0.02 mg/L. Extraction recovery was 77%-82%; method recovery 99%-102%; withinday RSD less than 3.0%; inter-day RSD less than 3.5%.