Interleukin-10 inhibits interferon-gamma-induced intercellular adhesion molecule-1 gene transcription in human monocytes

Interleukin-10 (IL-10) is a potent monocyte regulatory cytokine that inhibits gene expression of proinflammatory mediators. In this study, we investigated the mechanism by which IL-10 downregulates expression of intercellular adhesion molecule-1 (ICAM-1) on the cell surface of normal human monocytes activated with interferon-gamma (IFN-gamma). IL-10 inhibition of IFN-gamma-induced ICAM-1 expression was apparent as early as 3 hours and was blocked by an anti-IL-10 antibody but not by an isotype-matched control antibody. Northern blot analysis showed that IL-10 reduced the accumulation of ICAM-1 mRNA in IFN-gamma-stimulated monocytes. IL-10 inhibition of ICAM-1 steady-state mRNA was detected at 3 hours and remained at 24 hours. Nuclear run-on transcription assays showed that IL-10 inhibited the rate of IFN-gamma-induced transcription of the ICAM-1 gene, and mRNA stability studies showed that IL-10 did not alter the half-life of IFN-gamma-induced ICAM-1 message. Thus, IL-10 inhibits IFN-gamma-induced ICAM-1 expression in monocytes primarily at the level of gene transcription. Activation of IFN-gamma-responsive genes requires tyrosine phosphorylation of the transcriptional factor STAT-1alpha (signal transducer and activator of transcription-1alpha). However, IL-10 did not affect IFN-gamma-induced tyrosine phosphorylation of STAT-1alpha or alter STAT-1alpha binding to the IFN-gamma response element (IRE) in the ICAM-1 promoter. Instead, IL-10 prevented IFN-gamma-induced binding activity at the NF-kappaB site of the tumor necrosis factor alpha (TNF-alpha)-responsive NF-kappaB/C-EBP composite element in the ICAM-1 promoter. These data indicate that IL-10 inhibits IFN-gamma-induced transcription of the ICAM-1 gene by a regulatory mechanism that may involve NF-kappaB.

[Immunogenecity of expressed protein p68 from recombinant plasmid rpDJt in L. interrogans serovar lai]

There are two types of infection caused by pathogenic microorganisms, intracellular infection and intercellular infection. Infection of pathogenic leptospira is an intercellular infection. The immunological reaction of host to intercellular infection is unique. The potential immunogen of an expressed protein should meet three criteria: it can be degraded (by antigen-present cells in the host); it should have antigenic epitope which can be recognized by specific antibodies and have at least one epitope that can be recognized by an MHC II protein and T cell receptor. In this study we report the cloning of an L. interrogans protein in plasmid rpDJt and the immunogencity of the expressed protein derivative. A genomic library of L. interrogans serovar lai strain 017 was constructed with the plasmid vector pUC18. Recombinant plasmids, designated pDJH2 and pDJ8 were screened from the bank. EcoRI-inserted fragment of 1. 9 kb recombinant DNA of pDJH2 was ligated into T7 RNA polymerase/promoter vectors (pT7-7). Then they were transformed into E. coli JM109 (De3), one of subclones, designated rpDJt was achieved. SDS-PAGE showed that the molecular weights of expression proteins were 68 kd and 23 kd respectively, designated p68 and p23. Purifying and isolating p68 and p23, we separated them from SDS-Polyacrylamide gels by using Side-Strip method. After fragmenting and electroeluting, p68 and p23 were injected into guinea pigs and rabbits. An extremely strong immune response to p68 was obtained since an anti-p68 antibody response could be detected to a dilution 1:524,288 (guinea pigs) and 1:262,144 (rabbits) by ELISA while anti-P23 antibody being 1:1024 (the same to guinea pigs and rabbits). The results of improved MTT and conA 3HTdR transformation methods showed the activities and proliferation of Th-cells were increased in guinea pigs after p68 immunization (IL-6, 83.25 IU/ml, IL-2, 28.75 IU/ml; RPI, 2.04, SI, 65.62%) Thlymphocyte existed in two subclasses, the Th1- and Th2-cells. A major role of Th2-cells is to "help" B-cells differentiate, replicate, and secrete antibody. The properties of these interactions explain why p68 makes good antigen and p23 does not. The antigens responsible for eliciting the production of protective antibodies are not known; however, several outer membrane proteins on L. interrogans are candidates for vaccine. Our results suggest that expresion protein p68 from recombinants (rpDJt) may be a candidate for gene engineered subunit vaccine for Leptospirosis.

[The relationship between in vitro chemosensitivity of human breast cancer to MDR related drugs and expression of mdr-1 gene]

OBJECTIVE

To study the relationship between in vitro chemosensitivity of human breast cancer to MDR related drugs and expression of mdr-1 gene.

METHODS

We measured the chemosensitivity of 56 human breast cancers to MDR related drugs by MTT assay in vitro and level of mdr-1 mRNA in these samples by RT-PCR technique.

RESULTS

The expression of mdr-1 gene in the breast cancer resistant to drugs in vitro was increased significantly. The level of mdr-1 mRNA was not correlated with Imax%, but correlated with IC50 statistically.

CONCLUSION

These results support that the increased expression of mdr-1 gene is a major cause of resistance to MDR related drugs.

An HSV-1 vector containing the rat tyrosine hydroxylase promoter enhances both long-term and cell type-specific expression in the midbrain

A defective herpes simplex virus type one (HSV-1) vector that contains a 6.8-kb fragment of the rat tyrosine hydroxylase promoter (pTHlac-7kb) was examined for its capability to target catecholaminergic cell type-specific expression in the CNS. Cell type-specific expression was assessed by comparison with a control vector (pHSVlac) that uses the HSV-1 immediate early 4/5 promoter to support expression in multiple cell types. In initial experiments comparing expression in catecholaminergic and noncatecholaminergic cell lines, pTHlac-7kb supported a seven- to 20-fold increase in reporter gene expression in catecholaminergic cell lines. Four days after stereotactic injection into the midbrain of adult rats, pTHlac-7kb supported a 10-fold targeting of beta-galactosidase expression to tyrosine hydroxylase-expressing neurons in the substantia nigra pars compacta compared with pHSVlac. Expression from pTHlac-7kb was stably maintained for 6 weeks with no significant changes in the pattern of expression. Long-term expression from pTHlac-7kb was confirmed by RNA and DNA analysis. In contrast, reporter gene expression in the midbrain from pHSVlac decreased approximately 30-fold between 4 days and 6 weeks after gene transfer. Thus, within the context of this HSV-1 vector system, the tyrosine hydroxylase promoter enhanced cell type-specific expression and contributed to stable, long-term expression of a recombinant gene product in neurons. The capability to target recombinant gene expression to catecholaminergic neurons in specific brain areas may be useful for studies on the roles of these neurons in brain physiology and behavior.

Reconstruction of a cranial bone defect with hydroxyapatite and free flap transfer

The authors report a successful reconstruction of an extensive frontotemporal bone defect after craniotomy, which was complicated with infection and necessitated removal of frontal and temporal bones. The large frontotemporal bone defect was reconstructed using prefabricated hydroxyapatite blocks in combination with the free vastus lateralis muscle flap. The patient's functional and cosmetic restoration has been maintained for 10 months' follow-up.

[Construction of genomic library of L. interrogans serovar lai using lambda gt11 as the vector and a study of recombiant plasmid pDL121]

A genomic library of L. interrogans serovar lai strain 017 has been constructed using lambda gt11 as the vector. DNA was partially digested by two blunt-end restriction enzymes, then methylated with EcoR I methylase; after EcoR I linker was added to the DNA, the linker-ended DNA was ligated to the dephosphorylated EcoR I digested lambda gt11 arms. The recombined DNA was packaged in vitro, and used to transduct E. coli Y1090 for amplification. There were 2.1 x 10(6) recombinant bacteriophages as recognized by their ability to form white plaques plated on Lac host in the presence of both IPTG and X-Ga1. A positive clone, designated lambda DL12, was screened with a rabbit anti-serum against L. interrogans serovar lai from the genomic library. The DNA from lambda DL12 was subcloned into plasmid pUC18. A recombinant (designated as pDL121) was obtained. SDS-PAGE analysis indicated that a 23 kd was expressed in E. coli JM 103 harboring pDL121. Western blotting analysis showed that a specific protein band molecular weight of 23 kd could be recognized by the rabbit antiserum against L. interrogans serovar lai strain 017.

[Predictive chemotherapy of breast cancer directed by MTT assay in vitro]

OBJECTIVE

The predictive value of in vitro MTT assay for chemotherapy to breast cancer patients was studied.

METHODS

Of the 156 advanced breast cancer patients, 83 had had MTT assay before chemotherapy. According to the result of the MTT assay, 73 patients in MTT sensitive group received chemotherapy. The other 10 patients in MTT resistant group and 73 patients in the control group were given chemotherapy according to clinician' experience.

RESULTS

The response rate in MTT sensitive group was 76.7% (56/73). There was statistically significant difference as compared with 0(0/10) in the resistant group and 43.8% (32/73) in the control group. Between MTT sensitive group and control group, similar results were obtained at different therapeutic phases, in the subgroups of most lesions and chemotherapeutic schemes. Both the relapse rate and mortality rate were reduced remarkably in the MTT sensitive group. But there was no difference in the median remission and survival of relapsed patients in the two groups. Between in vitro and in vivo, the overall coincident rate was 79.5% [(56 + 10)/83].

CONCLUSION

The in vitro MTT assay can predict chemotherapy for breast cancer giving satisfactory results.

CCAAT-enhancer-binding protein alpha (C/EBP alpha) is required for the thyroid hormone but not the retinoic acid induction of phosphoenolpyruvate carboxykinase (PEPCK) gene transcription

Transcription of the gene for phosphoenolpyruvate carboxykinase (PEPCK) is stimulated by cAMP, the thyroid hormone tri-iodothyronine (T3) and retinoic acid (RA). Regulation of PEPCK transcription by T3 involves two sites in the promoter including a thyroid-hormone-response element (TRE) and a CCAAT-enhancer-binding protein (C/EBP) binding site called P3I. Mutation of either the TRE or P3I eliminates the T3 response. In this study, we examined the role of C/EBPs in the induction of PEPCK transcription by T3 and RA. PEPCK-CAT vectors were transfected into HepG2 cells. Co-transfection of a dominant negative C/EBP eliminated the T3 stimulation indicating that a member of the C/EBP family is required. To determine which C/EBP isoform was required, Gal4 fusion proteins were created that contained the Gal4 DNA-binding domain ligated to the transcriptional activation domain of C/EBP alpha, C/EBP beta or the cAMP-responsive-element-binding protein. A Gal4 DNA-binding site was introduced into the P3(I) site of the PEPCK-CAT vector. Only co-transfection of the Gal4-C/EBP alpha vector was able to restore T3 responsiveness to the PEPCK-CAT vector. The T3 and RA receptors are members of the nuclear receptor superfamily and bind to repeats of the AGGTCA motif. We found that the RA receptor can bind to sequences within the PEPCK-TRE and contribute to RA responsiveness of the PEPCK gene. However, the RA induction of PEPCK transcription was found to be independent of C/EBPs, further demonstrating the specificity of the involvement of C/EBP alpha in the T3 effect.

Transgenic murine dopaminergic neurons expressing human Cu/Zn superoxide dismutase exhibit increased density in culture, but no resistance to methylphenylpyridinium-induced degeneration

Primary dopaminergic neuronal cultures with increased superoxide dismutase (SOD) activity were established for studying the role of superoxide anion (O2-) in 1-methyl-4-phenylpyridinium (MPP+)-induced degeneration of dopamine (DA) neurons. Mean SOD activity in cultures prepared from transgenic (human) Cu/Zn SOD (hSOD1) mice was 2.46-2.60 times greater than in cultures prepared from nontransgenic control mice. After 1 and 2 weeks in culture, the mean density of DA neurons [number of tyrosine hydroxylase-immunoreactive (TH-ir) cells per visual field] was significantly higher in cultures prepared from transgenic mice compared with those prepared from nontransgenic control mice (4.55-5.63 TH-ir neurons per field in hSOD1 cultures vs. 2.66-2.8 TH-ir neurons per field in control cultures). However, uptake of [3H]DA relative to uptake of [3H]GABA was only slightly greater in hSOD1 cultures than in normal cultures (14.1 nmol of DA/100 nmol of GABA vs. 12.1 nmol of DA/100 nmol of GABA). Resistance to MPP+ toxicity was not significantly different from that in normal cultures when based on density of surviving TH-ir cell bodies (EC50 = 0.54 microM in hSOD1 and EC50 = 0.37 microM in normal cultures). A more sensitive measure of DA neuron integrity and function ([3H]DA uptake) also failed to demonstrate increased resistance of hSOD1 cultures to the toxin (EC50 = 73.7 nM in hSOD1 and EC50 = 86.2 nM in controls). These results do not support the hypothesis that neurotoxicity of the active metabolite of MPTP, MPP+, is mediated by generation of O2- in the cytoplasm. Nevertheless, mesencephalic cultures with increased hSOD1 activity appear to survive better than normal control cultures in the oxidatively stressful environment of cell culture incubators, and such mesencephalic cells may be useful for cell grafting studies in animal models of Parkinson's disease.

[Criteria of measuring mdr-1 gene expression level in breast cancer by RT-PCR]

OBJECTIVE

To formulate criteria of judjing multidrug resistance gene(mdr-1 gene) expression level and to provide basis for predicting chemotherapy response and prognosis.

METHODS

Using reverse transcription-polymerase chain reaction (RT-PCR) assay, the expression of mdr-1 gene in 82 breast cancer samples was detected. The data were treated by statistic analysis system (SAS)-singlevariate analysis.

RESULTS

The level of mdr-1 gene expression clearly deviated from normal to right distribution (P < 0.0001), and thus might be divided by quantiles P50(mdr-1/beta 2-MG = 0.2) and P75 (mdr-1/beta 2-MG = 0.6), which were taken as the criteria for comparing 56 patients' chemosensitivity to ADM, VDS, VCR in vitro and 32 relapsed metastatic patients' chemotherapy response in vivo, seperately. When mdr-1/beta 2-MG < 0.2, the ratio of coincidence was lower between expression of mdr-1 and drug resistance in vitro and in vivo; When mdr-1/beta 2-MG > or = 0.2-< 0.6, the ratio of coincidence elevated slightly, but in 30%-50% of the cases drug resistance in vitro and in vivo did not correlate. When mdr-1/beta 2-MG > or = 0.6, the ratio of coincidence elevated significantly. According to the above-mentioned results, criteria of evaluating mdr-1 gene expression level was formulated: the mdr-1/beta 2-MG ratio < 0.2(P50) was considered as negative expression, the ratio > or = 0.2-< 0.6(P75) was weakly positive expression, > or = 0.6 was strongly positive expression.

CONCLUSIONS

The criteria of mdr-1 gene expression may reflect objectively drug resistance in vitro and chemotherapy response in vivo. The method may also be applicable to other tumours.

[The effect of systemic and local irradiation on wound macrophages and the repair promoting action of phenytoin sodium]

OBJECTIVE

To study the effect of systemic and local irradiation on wound macrophages (M phi) and the pair promoting action of phenytoin sodium on irradiation-impaired wound healing.

METHODS

Wound M phi was collected by polyvinyl alcohol sponges which were implanted in a rat dorsum incision. The number of M phi, phagocytic function of wound M phi, and the release of tumor necrosis factor (TNT alpha) and interleukin-1 (IL-1) from wound M phi, and wound breaking strength (WBS) were respectively investigated.

RESULTS

WBS was deceased after 6Gy systemic irradiation and 20Gy local irradiation, and phenytoin sodium improved WBS in normal wound and radiation-impaired wound. After 6Gy systemic irradiation the phagocytic function of wound M phi, the release of TNF alpha and IL-1 from wound M phi, as well as the number of M phi in wound, were significantly decreased on days 3, 5, 8 after wounding. After 20Gy local irradiation, the ratio of M phi in wound cells was significantly decreased on days 3, 5, 8, 13 after wounding, but the function of macrophage was not significantly decreased. Phenytoin sodium significantly increased the number of wound M phi, improved the phagocytic function of M phi, and the release of TNF alpha and IL-I from wound M phi on days 3, 5, 8 days after wounding despite the rats were radiated or not.

CONCLUSION

The results indicated that the decrease of number and function of wound M phi play an important role in the impairment of early wound healing by systemic irradiation. Phenytoin sodium accelerated normal and irradiation-impaired wound healing by increasing the number of wound M phi and improving the M phi function.

[Research on the recombinant plasmid pDJH2 of L. interrogans serovar lai: sequencing and alignment with other known bacterial Omp sequence]

The Leptospira whole cell vaccine (LWCV) currently used in China is safe and effective, out the immunity following vaccination with two doses of the fluid medium vaccine is of low order. The duration of immunity conferred by this vaccine is rather short, six months or at most one year. Therefore, it is necessary to develop new generation vaccines against Leptospirosis for the developing world. In this paper we report the sequencing of the insert fragment of pDJH2 from genomic DNA of L. interrogans sevovar lai strain 017 and its alignment with other bacterial omp sequences. A genomic library of Leptospira interrogaans serovar lai strain 017 was constructed with the plasmid vector pUC18. A recombinant plasmid designated pJDH2 was screened from the genomic library. Inserted fragment of pDH2 is 1.9 kb by gel electrophoresis. Immunization/protection was studied in BALB/c mice model. The results showed highly significant difference between pDJH2 and pUC18 (control). Inserted fragment of pDJH2 DNA sequencing was performed by Dr Yan Zhengxin (Max-Planck-Institut for Biology. Tubingen, Germany). Insert fragment was cloned into pBluescript II KS-(stratagene) and sequenced by using AB1 (Applied Bio Systems, Model 373A). Two open reading frames of 565 and 662 nucleotides were identified. There were identifiable initiation codons, terminators, Shine-Dalgano ribosome combining site, Pribnow boxes and Sextama boxes within the 2 sequenced regions. Nucleotide sequences were analysed using Gene Work, a suit of computer program developed by Department of Biochemistry St. Jude Children's Research Hospital Memphis. U.S.A. The results of formatted alignment showed the predicted nucleotide sequence of ORF1 of the serovar lai had significant similarity with ORF2 (49.36%). L. kirschneri ompL1 (49.26%), Borrelia burgdoferi omp (48.97%), Treponema phagedenis omp (47.3%); Salmonella typhimurium ompC(46.87%), Yersinia enterocolitica ompH (46.7%), Leptospira borgpeterseni pfap (46.3%), and Serratia marcescens omp (43.3%). The close relationship of the pDJH2 ORF1 and ORF2 nucleotide sequences from Leptospira kirschneri ompL 1 is apparent. Whether the recombinant pDJH2 will prove useful for vaccine development remains to be tested.

[Subclones of fragment DNA recombinant rpDJH2 of L. interrogans serovar lai strain 017 and it's expression of high level in E. coli]

Fragment of 1.9 kb recombinant DNA of pDJH2 was linked with vectors pT7-7 and pRSETs. Then they were transformed into E. coli JM109 (DE3) respectively. Expression of subclones was achieved in E. coli JM109 (DE3) with IPTG inducement. SDS-PAGE showed that the molecular weights of products were 68kd and 23 kd respectively. The amount of production seemed to be higher than that of the outer membrane proteins of L. interrogans serovar strain 017 in nature. Immunoblotting of pDJt and pDJrB2 (both are subclones) with the specific antiserum of anti-OMP of L. interrogans serovar lai strain 017 and the experiment of initiative immuno-protection in guinea pigs showed both protein-68 kd and 23 kd might be the antigens of immuno-protection on the outer membrane of L. interrogans serovar lai strain 017.

Characterization and quantitation of the apoproteins of high-density lipoprotein by capillary electrophoresis

A method has been developed using capillary electrophoresis (CE) to quantitate plasma levels of apoprotein A-I (apoA-I) and apoprotein A-II (apoA-II) in high-density lipoprotein (HDL) samples. ApoA-I and apoA-II are resolved by CE in delipidated and non-delipidated HDL samples. Concentrations of apoA-I and apoA-II were calculated from their peak areas in the electropherogram. Results of the analysis of Sigma plasma standards (Controls 1 and 2) using CE are in good agreement with values obtained by Sigma using immunoturbidimetric assay. CE and reverse-phase high-performance liquid chromatography (RP-HPLC) were found to be complementary in the study of apoA-I and apoA-II. RP-HPLC resolves the isoforms of purified apoA-I and apoA-II, but it cannot resolve mixtures of them because the retention times of the isoforms overlap. CE separates apoA-I from apoA-II, but it does not resolve the isoforms. Matrix-assisted laser desorption/ ionization mass spectrometry was used to identify the isoforms of apoA-I and apoA-II by their molecular weight (M(r)) in fractions collected from RP-HPLC.

Failure rates of leads, pulse generators, and programmers have not diminished over the last 20 years: formal monitoring of performance is still needed. BILITCH Registry and STIMAREC

Formal Monitoring of Performance is Still Needed. In order to detect trends in the number of device or component failures that have occurred among permanent pacemaker systems since the 1970s, we reviewed the data of the five largest pacemaker manufacturers from the Bilitch Registry of permanent pacemaker pulse generators, the Stimarec failure registry, the general accounting office summaries of the United States Veterans Administration (VA) Registry of Pacemaker Leads, and the Implantable Lead Registry, from the Cleveland Clinic Lead registry, and the recalls and safety alerts issued by the United States Food and Drug Administration (FDA) over the last 20 years. The definition of failure followed the criterion, or criteria, developed within each registry and differed significantly between the registries. The 20-year period between 1976 and 1995 was divided into 5-year quartiles (QT): QT 1 = 1976-1980; QT2 = 1981-1985; QT3 = 1986-1990; and QT4 = 1991-1995. For pulse generators, the number of models with failures in each quartile in the Bilitch Registry were: QT 1 = 9; QT 2 = 11; QT3 = 17; QT4 = 13. In Stimarec, the number of units reported as having reached a dangerous condition were: QT1 = 710; QT2 = 212; QT3 = 114; QT4 = 310. From the FDA reports, the number of units included in recalls or safety alerts were: QT3 = 6,085; QT4 = 135,766. For permanent pacemaker leads, the numbers of failed or dangerous leads recorded in Stimarec were: QT3 = 16; QT4 = 32. In the VA Registry, the number of models having a below average survival was 2/92 (2.7%). In the Implantable Lead Registry, the number of models having a below average survival was 3/21 (14%). In the Cleveland Clinic series, 6/13 (46%) of lead models were recognized to have some failure involving the conductor, insulation, or connector. In the FDA reports, the number of leads involved in either recall or safety alert were: QT3 = 20,354; QT4 = 332,105. For programmers, the number of units involved either in a recall or safety alert were: QT3 = 11,124; QT4 = 3,528. In all of these series, each of the five largest manufacturers had some models or units involved in each time period. This review of programs has revealed: 1. The incidence of failures, recalls, or safety alerts did not decline over time; and 2. Despite changes in technology, formal monitoring of pacemaker systems is still warranted.

Cloning and characterization of the gene encoding Halobacterium halobium adenylate kinase

The gene (AK) encoding adenylate kinase (AK) of Halobacterium halobium was cloned. AK consisted of 648 bp and coded for 216 amino acids (aa). S1 mapping and primer extension experiments indicated that the transcription start point (tsp) was located immediately upstream from the start codon. The TAT-like promoter sequence was found at a position 20-24 bp upstream from tsp. The most striking property of the enzyme was a putative Zn finger-like structure with four cysteines. It might contribute to the structural stability of the molecule in high-salt conditions. Phylogenetic analysis indicated two lineages of the AK family, the short and long types which diverged a long time ago, possibly before the separation of prokaryotes and eukaryotes. Although the H. halobium AK belongs to the long-type AK lineage, it is located in an intermediary position between the two lineages of the phylogenetic tree, indicating early divergence of the gene along the long-type lineage.

Helper virus-free transfer of herpes simplex virus type 1 plasmid vectors into neural cells

Herpes simplex virus type 1 (HSV-1) plasmid vectors have promise for genetic intervention in the brain, but several problems caused by the helper virus have compromised their utility. To develop a helper virus-free packaging system for these vectors, the DNA cleavage/packaging signals were deleted from a set of cosmids that represents the HSV-1 genome. Following cotransfection into cells, this modified cosmid set supported replication and packaging of vector DNA. However, in the absence of the DNA cleavage/packaging signals, the HSV-1 genome was not packaged, and consequently vector stocks were free of detectable helper virus. In the absence of helper virus, the vectors efficiently infected rat neural cells in culture or in the brain with minimal cytopathic effects. beta-galactosidase-positive cells were observed for at least 1 month in vivo, and vector DNA persisted for this period. This system may facilitate studies on neuronal physiology and potential therapeutic applications.

[Dynamic analysis of cell surface markers in acute leukemias unclassified with immunologic criteria]

In order to study the cell origin of acute leukemia with lack of lineage specific antigen expression, the dynamic change of cell surface markers in 25 patients of acute leukemia unclassified with immunologic criteria were analysed by using APAAP immunoenzymatic method with monoclonal antibodies after chemotherapy or relapse. The results showed that 5 patients, whose leukemic cells expressed only CD38 antigen in the first visit, expressed T cell differentiated antigen after chemotherapy or relapse. 4 patients, who expressed B cell specific markers after chemotherapy or relapse, all expressed only CD9 antigen in the first visit. 4 of the 6 patients who expressed only HLA-DR antigen were found to have B cell markers on their leukemic cells surface after chemotherapy or relapse. One patient expressed B cell surface markers after chemotherapy and another expressed T cell surface markers after relapse, both of them expressed CD38 and HLA-DR antigens in the first visit. In 4 other patients whose leukemic cells were lacking of in any cell differentiated antigen expressing, one expressed B cell markers and another expressed T cell markers after chemotherapy. The change of cell surface markers showed the evolution and progression of leukemic cell clone. Dynamic study is useful to distinguish the cell origin of leukemia.

Site-directed mutagenesis of putative catalytic and nucleotide binding sites in N10-formyltetrahydrofolate synthetase

To determine the importance of specific amino-acid residues in catalysis and substrate binding by N10-formylH4 folate synthetase, one lysine and three histidine residues in the enzyme from Clostridium cylindrosporum were mutated to glutamine and serine residues, respectively. These residues, Lys-71, His-125, His-131, and His-268, are conserved in four bacterial and five eukaryotic proteins for which the amino-acid sequences are known. Previous evidence indicated that a histidine residue may play a role in catalysis and it has been proposed that Lys-71 could be a member of a putative nucleotide binding consenus sequence. The histidine mutations, H125S, H131S, and H268S, produced proteins that were unstable and were proteolytically degraded to different extents. No activity of purified H268S could be detected and the 240 kDa native tetramer was also absent. Activities of the H125S and H131S mutants could be measured and the Km values of the substrates were similar to those for the wild-type enzyme. It is concluded that the mutations resulted in monomers that do not fold properly and/or do not associate to the active tetramer and, as a consequence, are susceptible to intracellular proteolytic digestion. On the other hand, the K71Q mutation did not produce proteolyzed material. The resulting protein had a kcat value which was reduced by a factor of 3.3 x 10(-4). Km values of the substrates were not affected, nor were the affinty constants for MgATP and H4PteG3. CD and fluorescence spectra demonstrated that little change in the tertiary structure of the protein had occurred as a result of the mutation. The monomer form of K71Q was less stable than the monomer of the wild-type enzyme and reassociated less efficiently than the wild-type. From these results it is suggested that Lys-71 plays a critical role in catalysis by N10-formylH4 folate synthetase and that this residue may reside at an intersubunit interface.

[Color analysis of Vita shade guide]

In order to understand the reliability of the Vita Shade Guide and make it more resonably in applying, a series of tests were accomplished. Three Vita shade guides were selected in Beijing hospitals. By using the international color standard CIE1976LAB color system and CS-5 Spectrocolorimeter to measure, test and analyse the characteristics of the shade guides including the degree of color, color distribution, color stability and color difference. The results indicate: The tabs of each shade guide demonstrated the greatest color stability; most of the average color difference among the same number tabs of each guide are less than 1.5 NBS and the color range of shade guides are more limited than that of Chinese teeth crown.

The unique endometrial expression and genomic organization of the porcine IGFBP-2 gene

The insulin-like growth factor-binding proteins (IGFBPs-1-6) modulate the mitogenic and differentiative actions of the IGFs and may have IGF-independent functions. This study examined the gene expression and pregnancy-regulation of the IGF/IGFBP system in porcine uterine endometrium and myometrium during the periimplantation period and later stages of pregnancy. Endometrial IGFBP-2 mRNA abundance exhibited stage of pregnancy-dependent induction; whereas little or no IGFBP-2 mRNA was found in myometrium. IGFBP-2 protein was immunolocalized to the endometrial glandular and luminal epithelia (staining on day 60 > day 12) with minimal or no immunostaining of uterine stroma observed. IGFBP-3 and IGFBP-4 transcript levels became elevated in endometrium after implantation; whereas, IGFBP-5 and IGFBP-6 mRNAs were in greater abundance in periimplantation than post-implantation endometrium. IGFBP-1 transcripts, in contrast, could not be identified in porcine endometrium or myometrium of pregnancy. As a pre-requisite to understanding the pregnancy-induction and endometrial-specificity of the uterine-expressed IGFBP-2 gene, cosmids encompassing the pig IGFBP-2 chromosomal locus were isolated and characterized. This gene is comprised of four exons that span > 29 kb and encode a 316 amino acid precursor protein. All four exons were found to be G/C rich with exon 1 and immediate 5' flank exhibiting hallmarks of a CpG island. This latter region was devoid of TATA and CAAT motifs. Results identify the preferential endometrial expression of different IGFBP genes at either the periimplantation or post-implantation periods, perhaps reflecting distinct actions of these proteins at the embryo-maternal and feto-maternal interfaces, respectively. Interactions of steroid receptors, endometrial transcription factors and their corresponding cis elements may confer the unique uterine expression of the IGFBP-2 gene.

[Protective effects of chrominum on myocardial damage in rats]

To prove the protective effects of trivalent chromium (Cr3+) on myocardial damage, its ultrastructure and electro-physiological changes were observed in different groups of rats with intraperitoneal injection of normal saline, Cr3+ and selenium, and injection of adriamycin (ADR) by their tail vein. Results of ultrastructural observations showed nuclear margin of myocardial cells was obscure, cytoplasm became coarse and sparse, mitochondria vacuolar, myocardiofibril loose, broken and lytic in the group treated with ADR, myocardiopathic changes reduced and myocardial filaments arranged in good order in that with Cr3+ and selenium. QRS complex, Q-T interval, APD50 and APD90 in electrocardiograph (ECG) prolonged in the group with ADR and selenium, and no changes were observed in that with Cr3+. It suggests Cr3+ and selenium have apparently protective effects on rat's myocardium, and Cr3+ also can reverse the changes in ECG caused by ADR, which is of importance in prevention and treatment of cardiovascular diseases.

[Detection of expression of multidrug resistance gene in breast cancer by RT-PCR]

Using RT-PCR technique, we established a method for measuring expression of mdr-1 gene in breast cancer and the conditions affecting PCR results. Expression of mdr-1 gene was detected in 74 breast cancer samples. The results showed that 34.3%(12/35) untreated primary lesions and 59.0%(23/39) relapsed metastatic lesions had positive expression of mdr-1 gene (P < 0.05). In 32 patients, the overall correlation of mdr-1 gene expression with clinical drug sensitivity was 78.1%. The results validate that RT-PCR assay is highly sensitive, relatively quantitative and reliable for measuring levels of mdr-1 gene expression in clinical samples.

An improved quantitative RT-PCR fluorescent method for analysis of gene transcripts in the STS-65 space shuttle experiment

We describe a reverse transcription polymerase chain reaction (RT-PCR) technique using fluorescent dUTP to examine changes in mRNA level in samples. In this procedure, the amplified product is identified by the fluorescent detection system in an automated DNA sequencer, and if the MW of the DNA/RNA or the fluorescent dye is different, several samples can be analyzed in a single lane. The basis for this technique is similar to that of radiolabeled methods, and we applied this technique for the comparison of the expression level of the rat c-myc gene in osteoblasts exposed to microgravity and unit gravity conditions. Using the fluorescent- and radiolabeled methods, the level of rat c-myc mRNA were compared quantitatively and the results demonstrated that the c-myc expression level was not altered by microgravity. Therefore, this fluorescent RT-PCR technique is useful for gene expression analysis particularly when the samples are limited, such as in space flight experiments. The method also allows for rapid assessment of mRNA changes in many samples simultaneously.

[Investigation of urinary fibrinopeptide A level in pregnancy induced hypertension and its clinical significance]

OBJECTIVE

To investigate the changes of urinary fibrinopeptide A (FPA) level in pregnancy induced hypertension (PIH) and its clinical significance.

METHODS

High performance liquid chromatography (HPLC) was employed in determination. Urinary FPA was measured in 96 cases of normal pregnancy and 49 cases with PIH.

RESULTS

The urinary FPA levels in mild and moderate PIH groups were significantly higher than that in normal pregnancy (71.65 +/- 18.53 micrograms/L vs 40.17 +/- 20.26 micrograms/L, P < 0.01). The levels of urinary FPA in patients with preeclampsia increased significantly (146.65 +/- 32.53 micrograms/L) when compared with the mild and moderate PIH groups (P < 0.001). The levels of urinary FPA in patients with eclampsia (422.93 +/- 81.46 micrograms/L) were much higher than that in group of preeclampsia (P < 0.001).

CONCLUSIONS

It showed that the assay of urinary FPA might be helpful for earlier diagnosis, classification, treatment and judgement of prognosis in PIH.

[Finite element stress analysis of stress distribution endodontic posts at shoulder]

The objective of the present resarch is the comparative stress distribution of various design for post-core at shoulder. The purpose of this study was to analyse the stress distribution and concentration in the dentin of paralled-sided and taped posts by different shoulder designs with finite elements stress analysis method. It was found that stress tended to concentrate under the core shoulder with vertical force. When the force applied from the linqual side. The stress concentrated at the buccal side. The 90 degrees shoulder angles exhibited more even stress distribution than sharp shoulder angles. The analysis revealed that sharp angle should be avoided as occlusal shoulder in clinical practice because this design are less resistant to forces applied on them and are susceptible to fractures in the dentin.

Loss of deoxcytidine kinase expression and tetraploidization of HL60 cells following long-term culture in 1,25-dihydroxyvitamin D3

Development of drug resistance is a major problem in attempts to control the growth of neoplastic cell populations. The resistance can he either inherent or acquired by an exposure to a chemotherapeutic drug. The available models for study of these phenomena have not led to major improvements in the therapy for human cancers. Therefore, in order to develop a new model for such studies, we have exposed human myeloid leukemia cells HL60 to increasing concentrations of 1,25-dihydroxyvitamin D3 (1,25D3) and characterized the emerging new phenotypes of these cells over a period of 4 years. During the stepwise development of resistance only cells which did not adhere to the flask walls were passaged. Beginning at 30 nM 1,25D3 the sublines became resistant to the differentiation-inducing and growth-retarding properties of 1,25D3 even at 400 nM. Also, their growth rates in 1,25D3-free media increased. In addition, beginning at 40 nM 1,25D3 the sublines acquired resistance to 5-beta-D-arabinocytosine (araC) due to the lack of expression of the deoxycytidine kinase gene. The araC-resistant sublines were also near-tetraploid, as judged by their DNA content. When grown in 1,25D3-free long-term culture the phenotype was essentially stable. The development of cross-resistance to araC during growth in the presence of an unrelated compound (i.e., 1,25D3) shows that in some instances an apparently inherent drug resistance may in fact he due to a metabolic defect resulting from an exposure to another agent.

Expression of sarcoma-associated antigens p102 and p200 in human sarcoma cell lines

BACKGROUND

Understanding tumor antigen expression and its correlation with the cell cycle may help in designing immunotherapy by monoclonal antibodies. Therefore, we studied the in vitro expression of sarcoma-associated antigens p102 and p200 in the G, S, and G2/M phases of sarcoma cell lines.

METHODS

The expression of human cell surface sarcoma-associated antigens p102 and p200 was studied in 13 human sarcoma cell lines, using flow cytometry.

RESULTS

p102 was detected by monoclonal antibody 19-24-6 in all 13 sarcoma cell lines, and p200 was detected by monoclonal antibody 29-13-17 in five of 13. p102 antigen expression was 1.4- to 3.4-fold higher (p < 0.001) than p200 expression. Although sarcoma cell lines showed a wide range of p102/p200 antigen expression, over 99% of the entire in vitro and in vivo cell population was found to be p102- and/or p200-positive. In three cell lines, p102 expression was cell cycle-dependent, with relative fluorescence intensity ranging from 13.8% to 23.9% higher at the G1 phase than at the G2/M phase. In three cell lines, the expression of p200 at the GI phase was 22.4% to 40.9% percent higher than at the G2/M phase.

CONCLUSIONS

The heterogeneity and cell cycle dependence of p102/p200 antigen expression in sarcoma cells suggest that monoclonal antibodies 19-24-6 and 29-13-17 might be applied to the immunotherapy of sarcoma.

[Navelbine as a single agent to treat advanced breast cancers]

From March 1994 to March 1995, 14 cases of refractory advanced breast cancers were treated with Navelbine (NVB). NVB as a single agent was given weekly 40-60mg (24.9mg-33.3 mg/m2), every 2 weeks for one cycle. Six of fourteen cases (42.9%) achieved partial response (PR). The median remission duration of PR patients was 5 months (range 2-10 months). NVB was given 85 times, the main side effects were myalgia and arthralgia (80.0%), phlebitis (57.6%). Sixty-five of eighty five pretreatment WBC counts were below 4.0 x 10(9)/L, and the severity of leukopenia was related to pretreatment WBC level. No patient died of infection.

Generation of high-titer defective HSV-1 vectors using an IE 2 deletion mutant and quantitative study of expression in cultured cortical cells

Vectors based on herpes simplex virus type 1 (HSV-1) show promise for gene transfer into mammalian cells because of their wide host range, efficient infection and ability to deliver genes to nondividing cells. Defective HSV-1 vectors, or amplicons, are plasmid vectors which are unable to propagate on their own but contain specific HSV-1 sequences that, in the presence of helper virus, support DNA replication and subsequent packaging into virus particles. We compared three replication-incompetent HSV-1 mutants (KOS strain 5dl1.2, strain 17 D30EBA, KOS strain d120) as the helper virus for packaging the prototype defective HSV-1 vector, pHSVlac, which uses the HSV-1 immediate-early (1E) 4/5 promoter to regulate expression of the Escherichia coli lacZ gene. Use of 5dl1.2, which contains a deletion in the IE 2 gene, consistently produced virus stocks that contained a high level of vector, undetectable levels of wild-type HSV-1 and a ratio of vector to helper greater than 1. Virus stocks prepared using 5dl1.2 were superior to those prepared using helper viruses that harbor a deletion in the IE 3 gene, either D30EBA or dl20, and supported more efficient gene transfer than possible with previously published procedures. Lactate dehydrogenase efflux assays in rat cortical cultures showed that 5dl1.2 was no more cytotoxic than either D30EBA or dl20, despite the expression of more viral genes. Rat cortical cultures infected with pHSVlac packaged with either 5dl1.2 or D30EBA were used to quantify the stability of vector expression. Our results show a decrease in the number of cells with detectable levels of beta-galactosidase to 30% of peak levels after one week, irrespective of the helper virus used. However, simultaneous superinfection with 5dl1.2, but not with either D30EBA or dl20, produced a transient increase in the number of cells expressing beta-galactosidase. Superinfection with 5dl1.2 at 9 days after gene transfer increased the number of cells expressing detectable beta-galactosidase back to peak levels, most probably because of reactivation of the IE 4/5 promoter in pHSVlac. These results thus provide the first quantitative demonstration of long-term persistence of defective HSV-1 vectors in neurons.

[The PCR amplification, cloning, sequencing, expression in E. coli of gene encoding endoflagella subunit protein (fla B) from Leptospira interrogans serovar lai]

A pair of oligonucleotide primers were designed by ourselves to amplify the endoflagella gene of L. interrogans serovar lai. A fragment about 840 bp was generated with PCR and inserted into plasmid pUC8 after the fragment and pUC8 were digested respectively with Bam HI and Pst I. A recombinant plasmid (designated as pLF1) was obtained. SDS-PAGE analysis indicated that a 33 kd was expressed in E. coli JM103 harboring pLF1 and the expression level of the protein was 11% of total bacterial soluble proteins. Western blot analysis showed that the protein band could be recognized by the antiserum against the endoflagella (Axiall filament) of Leptospira interrogans serovar lai. Nucleotide seguence data showed an open reading frame encoding 282 aminoacids residues, corresponding to a protein of molecular weight 33.6 kd. The G + C content of endoflagella subunit protein gene was 48 mol%. Therefore, the G + C content of the leptospiral fla B Gene is significantly higher than the reported 39 mol% G + C content of leptospiral genome of L.interrogans serovar lai but similar to the G + C of the Treponema pallidum genome. Comparison of the deduced endoflagellar subunit protein (fla B) amino acid sequence with flagellins from other bacteria revealed a high level of identity with the Treponema pallidum fla B proteins. Immunization/protection experiment was performed on the model of BALB/c mice and showed that the survival rate in the group JM103-pLF1 was higher than that in the group JM103-pUC8, but statistically the difference between them was significant (P < 0.05) and pLF1 did not induce significant levels of agglutinating antibodies against L.interrogans serovar lai.

Bilateral vertebral artery tortuosity with concomitant vertebral erosion: CT and MRA findings

Focal vertebral artery tortuosity has been periodically reported as a rare cause of cervical vertebral body and foraminal erosion. Almost all reported cases are unilateral. A case of bilateral vertebral artery tortuosity is described with computed tomography and magnetic resonance angiography findings included.

IL-10 cooperates with TNF-alpha to activate HIV-1 from latently and acutely infected cells of monocyte/macrophage lineage

IL-10 is elevated in HIV-1-infected individuals and has been implicated in disease progression. In this study, we investigated the effects of IL-10 on the activation of HIV-1 from infected monocytes and macrophages. Although IL-10 alone did not induce HIV-1 replication, in the presence of TNF-alpha, IL-10 markedly enhanced virion production from a chronically infected promonocytic cell line (U1) and in acutely infected monocyte-derived macrophages. Neutralizing mAbs to IL-10 and TNF-alpha indicated that both cytokines were essential for the induction and were required to generate a synergistic increase in virus expression. The effects of the two cytokines were distinguishable functionally since pretreatment with TNF-alpha attenuated the cytokine cooperativity, while pretreatment with IL-10 potentiated their cooperativity, suggesting that IL-10 and TNF-alpha play different roles in the activation of virus. Northern blot analysis as well as Ab blocking and cytokine secretion studies indicated that the induction of either endogenous TNF-alpha or IL-10 was not involved in the cooperativity, nor was an up-regulation of TNF-alpha receptors. In combination with TNF-alpha, IL-10 stimulated activating protein-1 (AP-1) and nuclear factor (NF)-kappa B binding activities and cooperated to increase HIV-1 steady-state mRNA levels and enhance long terminal repeat-directed transcription through activation of the NF-kappa B binding sites, suggesting the IL-10 effect occurs at least in part at the transcriptional level. These results indicate that IL-10, in addition to down-regulating the cellular immune response to HIV-1, may also play a role in TNF-alpha-mediated activation of HIV-1 replication in the monocyte/macrophage lineage.

IL-10 cooperates with TNF-alpha to activate HIV-1 from latently and acutely infected cells of monocyte/macrophage lineage

IL-10 is elevated in HIV-1-infected individuals and has been implicated in disease progression. In this study, we investigated the effects of IL-10 on the activation of HIV-1 from infected monocytes and macrophages. Although IL-10 alone did not induce HIV-1 replication, in the presence of TNF-alpha, IL-10 markedly enhanced virion production from a chronically infected promonocytic cell line (U1) and in acutely infected monocyte-derived macrophages. Neutralizing mAbs to IL-10 and TNF-alpha indicated that both cytokines were essential for the induction and were required to generate a synergistic increase in virus expression. The effects of the two cytokines were distinguishable functionally since pretreatment with TNF-alpha attenuated the cytokine cooperativity, while pretreatment with IL-10 potentiated their cooperativity, suggesting that IL-10 and TNF-alpha play different roles in the activation of virus. Northern blot analysis as well as Ab blocking and cytokine secretion studies indicated that the induction of either endogenous TNF-alpha or IL-10 was not involved in the cooperativity, nor was an up-regulation of TNF-alpha receptors. In combination with TNF-alpha, IL-10 stimulated activating protein-1 (AP-1) and nuclear factor (NF)-kappa B binding activities and cooperated to increase HIV-1 steady-state mRNA levels and enhance long terminal repeat-directed transcription through activation of the NF-kappa B binding sites, suggesting the IL-10 effect occurs at least in part at the transcriptional level. These results indicate that IL-10, in addition to down-regulating the cellular immune response to HIV-1, may also play a role in TNF-alpha-mediated activation of HIV-1 replication in the monocyte/macrophage lineage.

Effects of long-term acclimatization in lowlanders migrating to high altitude: comparison with high altitude residents

The physiological response to submaximal and maximal exercise was assessed in lowlanders and Tibetans at low (500 m above sea level) and high altitude (HA, 3,680 m). The times spent at HA by the lowland migrators was 8 days (n = 60), 7 months (n = 60, same group), 15 months (n = 29) and 27 months (n = 29). After the 15-month stay at HA, the maximal oxygen uptake (VO2max) and maximal heart rate of the lowland migrators almost reached those of the HA native residents (Tibetans, n = 57), but their total work capacity and the gross efficiency (eta) of mechanical work remained lower than those of the Tibetans. The rate of VO2max achieved at 90 W by the Tibetans was lower than that of the lowland migrators. It was concluded that, at HA, the lowlanders regained much of the aerobic capacity which they had lost initially. However, they did not attain the same gross mechanical efficiency as the Tibetans, who seemed to be at an advantage in respect of work at HA.

High grade prostatic intraepithelial neoplasia in prostates removed following irradiation failure in the treatment of prostatic adenocarcinoma

Prostatic Intraepithelial Neoplasia (PIN) is widely considered to be a precursor lesion for adenocarcinoma of the prostate. No information is available, however, on the sensitivity of PIN to irradiation or the distribution of residual PIN after radiotherapy. We studied a series of forty-six totally embedded, whole mounted, serially sectioned prostates removed by salvage radical retropubic prostatectomy following irradiation failure in which no hormonal therapy/ablation had been undertaken. The mean age of patients was 65 (56-74) years, the mean dose of radiotherapy was 7,266 (6,000-9,000) cGy (15 external beam, 27 external beam plus iridium or gold seed, 3 iodine, and 1 unknown) and the mean interval for irradiation therapy to prostatectomy was 60 (16-145) months. Thirty-two (70%) of the patients had high grade PIN within the prostatectomy specimen. The pattern of PIN was recorded as described by Bostwick and co workers. The frequency of the different patterns per positive case paralleled in rank those in Bostwick's series of non-irradiated prostates, with the most common to least common per patient being: tufting (78.1%), micropapillary (59.3%), cribriform (34.4%) and flat (15.6%). However, the mean number of foci of PIN per prostate was less than in Bostwick's series (7.1 foci vs. 17 foci). There was no statistically significant difference between groups with or without high grade PIN with regard to various clinical factors (last preoperative serum PSA, age, dose of radiotherapy, interval from irradiation therapy to prostatectomy, Kaplan-Meier survival), or pathologic factors (presence of confined tumor, extracapsular extension, positive surgical margins, seminal vesicle invasion, or positive lymph nodes on permanent sections). We conclude that high grade PIN is common in the prostates of patients who have failed irradiation therapy and that, theoretically, not all recurrent tumors derive from regrowth of the initial, incompletely eradicated tumor. However, because there was no significant difference between the two groups with regard to the clinical and pathologic parameters listed, we consider it likely that most recurrent tumors derive from the initial incompletely eradicated tumor.

[Homology of the recombinant DNA of plasmid pDJH2 with the recombinant DNA probe of L. alstoni and analysis of its expression in Escherichia coli]

Dig-labeled recombinant DNA probe of L. alstoni which contains the entire structural OmpL1 gene was hybridized with the recombinant DNA of the plasmid named pDJH2 of the gene library of L. interrogans serovar lai strain 017. The result showed a high degree of homology among them; expression of recombinant DNA of pDJH2 was achieved by beta-D-galactosidase (IPTG) induction in E. coli. The molecular weight of this product is 68kd. Then they were treated with proteinase K and subjected to SDS-PAGE. The results showed it is a protein in nature. Using the specific monoclonal antibody E4B7D5 on immunoblotting and specific polyclonal antibody on dot-ELISA assay, we investigated the immune reaction and noticed that protein 68kd might be an antigen in character. E. coli which contains the recombinant plasmid pDJH2 were injected into BALB/c mice. Then the mice were challenged by leptospires of the strong virulence strain 017, but all the infected mice survived. In this paper, we first report the expression of recombinant DNA of L. interrogans serovar lai strain 017 in E. coli when injected with IPTG, and immunoprotection of BALB/c mice which were injected with the expression against the infection of L. interrogans serovar lai strain 017. pDJH2 may be the first recombinant for which the gene has been cloned and its expression product 68kd may be the immunoprotective antigens.

[Operative management of retroperitoneal tumors involving major blood vessels: a report of 20 cases]

We report the experience of operative management in 20 patients with retroperitoneal tumors with major adjacent blood vessels involved, including portal vein inferior vena cava, abdominal aorta, iliac and renal vessels, and superior mesenteric vein. The diagnosis, preoperative preparation, intraoperative management and the postoperative complications were discussed. We emphasize the importance of radical resection of the tumors involving major blood vessels and vascular reconstruction.

Direct measurement of intratumor dose-rate distributions in experimental xenografts treated with 90Y-labeled radioimmunotherapy

PURPOSE

To measure, quantify, and evaluate the planar dose-rate distribution for human tumor xenografts implanted into mice that are treated with 90Y-labeled monoclonal antibodies or bispecific antibodies and 90Y-labeled haptens.

METHODS AND MATERIALS

Twenty-five LS174T human colon carcinoma tumors grown subcutaneously in nude mice were treated with 90Y by either directly labeled ZCE025 or bispecific ECA001-DBX antibody systems. A simple, quick technique using GAF radiochromic medium determined the dose-rate distribution in a plane passing through the tumor center. The dose-rate distribution is generated from exposure to activity situated in one-half of the tumor (0.045 to 0.83 g).

RESULTS

Planar dose-rate distributions were obtained from the tumor xenografts. Planar dose-rate histograms were computed along with the coefficients of variance and skewness of the distributions. The observed dose-rate distributions were quantitatively compared to those calculated for a uniformly distributed activity in a half-ellipsoid of the same volume and approximate shape as the tumor half. The observed dose-rate distributions were usually broader with a more positive coefficient of skewness than the dose-rate distributions calculated from the uniformly active half-ellipsoids. For 90Y, tumor shape plays an important role in determining the minimum tumor dose. For these tumors, the tumor minimum dose-rate is always observed along the edge, usually where the edge curvature is most convex. Larger tumors tended to have broader dose-rate distributions and more positive coefficients of skewness. Exceptions to this trend were associated with dose-rate maxima displaced from the central regions due to activity heterogeneity or tumor size greatly exceeding the range of emission. Calculations for dose rate from the conventional Medical Internal Radiation Dose (MIRD) formulation exceeded the average and minimum dose rate derived from radiochromic media. The coefficient of skewness became more positive for increasing time between injection and tumor excision, consistent with the activity evolving into a more uniform activity distribution.

CONCLUSION

Using radiochromic media to measure the spatial dose-rate distribution is a valuable method for comparing the dose-rate heterogeneity among experimental tumor xenografts in animals treated with radiolabeled antibodies. Tumor size (relative to the particle range) and changes in activity distribution radiolabeled antibodies. Tumor size (relative to the particle range) and changes in activity distribution affect the dose-rate distribution that are reflected by changes in the coefficients of skewness and variation of the dose-rate area histogram. The increase in coefficients of variation and skewness with tumor size and time results from the size of the 90Y beta particle penetration range that either exceeds or is comparable to the tumor dimensions. The minimum dose rate is more dependent, relative to the average and the maximum dose rates, on the curvature of the tumor surface.

[Evaluation of chemosensitivities of human breast cancers by primary culture assay in vitro]

Chemosensitivities of 32 human breast cancer to 6 antitumor drugs were assayed in vitro using MTT colorimetric method. The results showed that the chemosensitivity of primary breast cancer cultures varied remarkably from one patient, and from one drug, to another with hundred-to thousand-fold differences. The distribution of 50% inhibition concentration (IC50) was significantly deviated from normal distribution (P < 0.0001), and the drug sensitivity could be divided into four different catagories by means of percentile method. Preliminary results showed that the in vitro chemosensitivities of different antitumor drugs were consistent with the clinical therapeutic responses It seems that the herein reported assay might be useful on an individual basis to optimize chemotherapy of human breast cancer.

A multicentred phase III comparative clinical trial of Mesigyna, Cyclofem and Injectable No. 1 given monthly by intramuscular injection to Chinese women. I. Contraceptive efficacy and sid effects

A phase III clinical study was carried out among 5680 fertile Chinese women to evaluate efficacy and side effects of three monthly injectable contraceptives: Mesigyna, Cyclofem and Chinese Injectable No. 1. When used in a once-a-month treatment schedule (part 1 of study), the effectiveness of Chinese Injectable No. 1 was unacceptably low; 36 pregnancies occurred during the first 1743 women-months of use, 16 before the second injection. The study was restarted with a revised injection schedule for Injectable No. 1: two injections separated by 9 +/- 1 days during the first month and subsequent injections given 10-12 days after the onset of bleeding, or if no bleeding occurred, 28 days after previous injection. In part 2 of the study, 988, 990 and 992 subjects were provided Mesigyna, Cyclofem and Injectable No. 1, respectively. Life-table pregnancy rates at one year were 0.41%, 0% and 0.77% (p < 0.05), respectively; the overall discontinuation rates at one year were 13.9%, 19.1% and 20.4% (p < 0.001). Discontinuation rates for bleeding problems were significantly different between the groups: discontinuation rates for amenorrhea were 0.58%, 3.71% and 0.68% (p < 0.001) for Mesigyna, Cyclofem and Injectable No. 1; for other bleeding problems, the rates were 4.88%, 8.38% and 12.64% (p < 0.001). There were no significant differences between the groups regarding discontinuation for other medical or non-medical reasons. Mean weight changes after one year of use were small: 0.73, 0.86 and 0.17 kg for the three groups, respectively. Both Mesigyna and Cyclofem were very effective for contraception, but Mesigyna appeared to be tolerated slightly better with regard to cycle control; the modified dose regimen for Injectable No. 1 also gave a low pregnancy rate but was associated with higher rates of discontinuation.

A multicentred phase III comparative clinical trial of Mesigyna, Cyclofem and Injectable No. 1 given by intramuscular injection to Chinese women. II. The comparison of bleeding patterns

Between 1988 and 1992, a randomized phase III clinical trial was conducted in China to compare three monthly injectable contraceptives: Mesigyna, Cyclofem and Injectable No. 1. This paper presents a detailed analysis of the menstrual diaries provided by 5098 (89%) of the subjects. In total, 902, 903 and 913 diaries were analyzed to compare bleeding patterns induced by Mesigyna, Cyclofem and Injectable No. 1. The first withdrawal bleeding usually occurs 14-20 days after the first injection for all three of these preparations. Thereafter, 50% of Mesigyna users had precisely 3 bleeding/spotting episodes every 90 days, 50% of Cyclofem users had 2-3 and 50% of Injectable No. 1 users had 3-4 episodes every 90 days. Relative to users of Mesigyna or Cyclofem, Injectable No. 1 users had 2-3 more bleeding/spotting days, and a shorter length of bleeding/spotting-free intervals in each period. 63.7%, 41.4% and 60.6% of subjects using Mesigyna, Cyclofem and Injectable No. 1, respectively, had bleeding patterns similar to their untreated patterns in the first 90-day period. The percentages increased to 82.2% 67.8% and 75.0% in the fourth 90-day period. A total of 1815 diaries for Mesigyna and 1802 for Cyclofem were analyzed for more in depth comparison of these two methods. The number of bleeding/spotting days over four periods showed little difference between the two group, but there were more spotting days and there was greater individual variability among Cyclofem users.(ABSTRACT TRUNCATED AT 250 WORDS)

Application of fluorescent dUTP on PCR and automated PCR product detection by using internal lane size standard

A convenient, simple, cost effective and efficient fluorescent PCR labeling for automated detection was developed by using fluorescent deoxyuridine triphosphate-(F)dUTP without changing any PCR reaction parameters. Multiple fluorescent (F)dUTPs in a broad range of concentration were tested on PCR reaction and then titration tests for optimum sample loading amount with automated detection were done by using Genescan 672 software on ABI 373A DNA sequencer. PCR product were automaticaly detected although the sensitivity of each color was different. Colors of (F)dUTP and (F)dUTP/dTTP ratio showed a significant influence on the incorpration of (F)dUTP in PCR reaction, so consequently the ratio gave a great impact on the PCR product detection results. To much incorpration of (F)dUTP changed the PCR fragment mobility and also sizing value. The application of (F)dUTP should have a great potential on linkage studies, mapping with microsatellite and mutation detection.