Further evidence for a susceptibility locus for type 2 diabetes on chromosome 20q13.1-q13.2

We previously reported suggestive linkage between type 2 diabetes and markers in a region on chromosome 20q using data from a collection of 29 Caucasian families in which type 2 diabetes with middle-age-onset was segregated as an autosomal-dominant disorder. To map more precisely the susceptibility locus (or loci) within this broad region, we increased the family collection and genotyped all families for additional markers, both within the critical region and spaced over the rest of chromosome 20. Altogether 526 individuals (including 241 with diabetes) from the total collection of 43 families were included in the study. All individuals were genotyped for 23 highly polymorphic markers. Positive evidence for linkage was found for a 10-cM region on the long arm of chromosome 20q13.1-q13.2 between markers D20S119 and D20S428. The strongest evidence in two-point as well as multipoint linkage analysis (P = 1.8 x 10(-5)) occurred at the position corresponding to marker D20S196. The individuals with diabetes in the seven most strongly linked families had high serum insulin levels during fasting and 2-h post-glucose load periods. We did not find any evidence for linkage between type 2 diabetes and any other region on chromosome 20. In conclusion, our larger and more comprehensive study showed very strong evidence for a susceptibility gene for insulin-resistant type 2 diabetes located on the long arm of chromosome 20 around marker D20S196.

[Influence of solid thoracolumbar kyphosis on lumbar spine and surgical treatment]

OBJECTIVE

To investigate the influence of solid thoracolumbar kyphosis on the lumbar spine and surgical treatment.

METHODS

14 had solid kyphosis of the thoracolumbar spine. Cobb angle of kyphosis of the thoracolumbar spine and lordosis between L(2)/S(1), L(2)/L(5), L(2)/L(3), L(3)/L(4), L(4)/L(5), L(5)/S(1) pre- and post-osteotomy was measured respectively, and the amount of vertebrae slipped over 3mm was recorded. The results were compared with those of the normal group respectively.

RESULTS

The Cobb angles of lordosis between L(2)/S(1), L(2)/L(5), L(2)/L(3), L(3)/L(4), L(4)/L(5), L(5)/S(1) in the deformity group were increased significantly compared with those that of the normal group respectively; obvious changes in percentage occurred in the segment between L(2)/L(3) and L(3)/L(4). Over lordosis of the lumbar spine was greatly corrected postosteotomy of the thoracolumbar spine, it was still significantly different compared with that of the normal group. In 9 patients with retrolisthesis of 20 vertebrae, 70% occurred in L(2) and L(3) vertebrae. The amount of retrolisthesis of vertebrae decreased to 3 in two patients. No retrolisthesis of vertebra was seen in the normal group. Single-stage procedures combined with anterior releasing and posterior osteotomy through facet joints for kyphosis of the thoracolumbar spine showed a correction. rate of 85.7%, but single-stage osteotomy through the posterior vertebra showed a correction rate of 60.7%. Seven of 8 patients who had had seriously back pain complained of no pain or slight backache after operation. 40% of the patients showed functional improvement in the sphincter of the urinary bladder and anus. 50% of the patients had improvement in muscle strength.

CONCLUSIONS

Kyphosis of the thoracolumbar spine may result in over lordosis of the lumbar spine and retrolisthesis of vertebrae, which are obvious in the upper lumbar spine. These changes may lead to back pain. Correction of kyphosis of the thoracolumbar spine may obviously decrease over lordosis of the lumbar spine and inclination of vertebral slip, and may further decrease the overload to the posterior column of the spine and relieve back pain. Osteotomy combined with anterior and posterior procedures is effective and safe in the correction of kyphosis of the thoracolumbar spine.

Antiviral activity of mixed-valence rare earth borotungstate heteropoly blues against influenza virus in mice

The acute and accumulated toxicity of the rare earth borotungstate heteropoly blues, HPB-2, Ce2H3[BW9(VI)W2(V)Mn(H2O)O39].12H2O, which is active against influenza virus in Kunming mice, were investigated in Kunming mice following oral and intraperitoneal administration. The activity of HPB-2 against influenza virus (FM1) in the mice was then investigated. HPB-2, given either orally (p.o.) or intraperitoneally (i.p.), was shown to have activity. HPB-2 was shown to be more effective than the positive control, ribavirin, and it was also found that i.p. administration was more effective than p.o. administration.

[Effect of elevated CO2 concentration on growth of dominant tree species in pine broadleaf forest of Changbai mountain]

Potted saplings of Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica, and Acer mono, the eight dominant species in the Korean pine broadleaf forest at Changbai Mountain, were grown in open-top chambers with ambient(400 microliters.L-1) and elevated (700 microliters.L-1) CO2 concentration under natural sunlight for two growing seasons. The average height growth of these eight species under elevated CO2 increased by 10%-40%, compared with the control at ambient CO2. The response of transpiratory rate to the higher CO2 concentration was different among the species, and the water use efficiency of the saplings of the 8 species growing under elevated CO2 concentration was higher than that under ambient CO2. Soluble sugar and chlorophyll contents were not related to the CO2 concentration under which the saplings grew, indicating that the complicacy was existed in the acclimation of tree species to high CO2 concentration. The response of broad-leaved tree species to the elevated CO2 concentration was more sensitive than that of conifer tree species. Saplings of all tree species showed a photosynthetic acclimation to higher CO2 under long-term elevated CO2 concentration.

Insulin-like growth factor binding protein-6 activates programmed cell death in non-small cell lung cancer cells

Insulin-like growth factor binding proteins (IGFBPs) are secreted into the extra-cellular matrix and inhibit cell growth through IGF-dependent and -independent mechanisms. In this study, we investigated the role of IGFBP-6, a relatively unexplored member of the IGFBP family, in the proliferation of non-small cell lung cancer (NSCLC) cells. Infection of NSCLC cell lines in vitro with an adenovirus expressing human IGFBP-6 under the control of a CMV promoter (Ad5CMV-BP6) reduced NSCLC cell number through activation of programmed cell death, as shown by cell staining with Hoechst 33342 or DNA end-labeling with bromodeoxyuridine triphosphate. The growth regulatory effect of IGFBP-6 was investigated in vivo by intratumoral injection of Ad5CMV-BP6 in NSCLC xenografts established in nu/nu mice. A single injection of Ad5CMV-BP6 reduced the size of NSCLC xenografts by 45%. These findings indicate that IGFBP-6 is a potent inducer of programmed cell death in cancer cells and support investigations into IGFBP-6 as a potential target in cancer therapeutics.

Insulin-like growth factor binding protein-6 inhibits the growth of human bronchial epithelial cells and increases in abundance with all-trans-retinoic acid treatment

Retinoids are potent inhibitors of human bronchial epithelial (HBE) cell growth. Retinoids initiate signaling through activation of nuclear receptors, but the signal transduction pathways that mediate growth inhibition have not been defined. In this study, we investigated the expression of insulin-like growth factor (IGF)-binding protein (IGFBP)-6 as a potential mediator of retinoid actions. IGFBP-6 is a secreted glycoprotein that inhibits the bioavailability of IGFs, which are potent mitogens of HBE cells. IGFBP-6 was detected by immunohistochemical staining in the basal epithelial layer of human bronchial organ cultures, and all-trans-retinoic acid (t-RA) treatment increased the intensity of IGFBP-6 immunostaining. In primary cultures of HBE cells treated with t-RA, IGFBP-6 messenger RNA and protein levels increased within 6 and 24 h, respectively, and IGFBP-6 was detected in the conditioned media at 48 h. The effect of IGFBP-6 on HBE cell growth was investigated with a recombinant adenoviral vector, Ad5CMV-BP6, which expresses IGFBP-6 under the control of a cytomegalovirus promoter. IGFBP-6 overexpression induced a proliferative arrest of HBE cells with no evidence of apoptosis. These findings provide the first evidence that IGFBP-6 is expressed in the bronchial epithelium and that IGFBP-6 may contribute to the biologic effects of retinoids on HBE cells.

[The study of induced circular dichroism of phenylalanine bridged metal bis-porphyrin]

L- and D-phenylalanine bridged zinc bis-porphyrin with the connecting chain at ortho and para position of two phenyl rings [o,o-C2-Phe-C2-(TPP)2Zn2 and p,p-C2-Phe-C2-(TPP)2Zn2] have been synthesized and characterized. o,o-C2-Phe-C2-(TPP)2Zn2 exhibited strong induced circular dichroism (ICD). While p,p-C2-Phe-C2-(TPP)2Zn2 exhibited no significant ICD. The ICD of present complexes were mainly determined by the pi-pi interaction and chiral excition coupling between two porphyrin moieties of the molecules. Our results also indicated that the existence of chiral center in a porphyrin molecule does not mean it would surely exhibit ICD.

Identification of the cable parameters in the somatic shunt model

We show that the first five moments of the soma potential and soma current uniquely and stably determine the soma conductance and capacitance and the dendritic electrotonic length, conductance, and capacitance in the so-called somatic shunt model of the passive behavior of a neuron. We test our resulting input admittance algorithm on synthetic data and demonstrate the regularizing effect of knowledge of the ratio of soma to dendrite surface areas.

[The role of Werner's syndrome gene in the genetic susceptibility to the type 2 diabetes in Chinese population]

OBJECTIVE

To test the hypothesis that Werner's syndrome gene (WRN) contributes to the genetic susceptibility to the type 2 diabetes in Chinese population.

METHODS

Polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP) method was used to test the distribution of a polymorphism (Cys1367Arg ) of the WRN gene in 241 type 2 diabetes patients and 108 normal control subjects.

RESULTS

The frequency of "R" allele of the WRN gene in type 2 diabetes patients whose diagnosis age >/= 45 was significantly increased as compared with that in the control subjects (9.6% vs 4.6%, P = 0.04).

CONCLUSION

The high frequency of allele "R" of the WRN gene in early onset Chinese type 2 diabetes patients suggests that the WRN gene may contribute to the genetic susceptibility of type 2 diabetes in Chinese population through either directly causing diabetes or interacting with the diabetogenic gene.

[Relationship between human herpesvirus 6 infection and idiopathic thrombocytopenic purpura]

OBJECTIVE

To investigate the pathogenic role of human herpesvirus 6 (HHV-6) in idiopathic thrombocytopenic purpura (ITP).

METHODS

HHV-6 DNA was examined by polymerase chain reaction (PCR) in bone marrow mononuclear cells (BMMNC) of 105 ITP patients. Human cytomegalovirus (HCMV) and parvovirus B(19) DNA were also examined in some cases. Platelet-associated antibodies (PAIg) were measured by competitive ELISA in 66 ITP patients. Serum IgG titer to HHV-6 was observed by indirect immunofluorescence assay in 19 ITP patients.

RESULTS

(1) HHV-6 DNA positivity was 41.0% for ITP patients, significantly higher than that for control group (P < 0.05). HHV-6 DNA positivity for adult ITP patients, especially adult chronic cases was significantly higher than that for childhood patients (P < 0.025). Positivities for parvovirus B(19) and HCMV DNA were 24.1% and 9.7%, respectively. (2) HHV-6 DNA positivity for patients with abnormal level of PAIgG was significantly higher than that for patients with normal level of PAIgG (P < 0.05). (3) Patients coinfected with HHV-6 and B(19) or HCMV had more severe symptoms or poorer prognosis.

CONCLUSION

HHV-6 infection might be associated with excessive PAIgG. Coinfection with HHV-6, B(19) or HCMV may cause more severe symptoms in ITP patients.

Antitumor effect of adenovirus-mediated Bax gene transfer on p53-sensitive and p53-resistant cancer lines

Antitumor effects of the proapoptotic Bax gene have been evaluated in vitro and in vivo by a binary adenovirus system expressing the human Bax gene. Overexpression of the Bax gene in cultured cell lines from human lung carcinoma results in caspase activation, apoptosis induction, and cell growth suppression. Intratumoral injection of adenovirus vector expressing the Bar gene suppressed growth of human lung cancer xenografts established in nude mice. Histological examination of tumors from mice treated with the Bax gene demonstrated high levels of Bax expression and extensive apoptosis in tumors. In comparison with the treatment by an adenoviral vector expressing human p53, the Bax gene can effectively suppress tumor growth in both p53-sensitive and p53-resistant human lung carcinoma cell lines. Toxicity was not detected in liver and other systems in animals treated intralesionally with the Bax gene. Therefore, our results suggest that the Bar gene may be useful in cancer treatment.

A binary adenoviral vector system for expressing high levels of the proapoptotic gene bax

The bax gene plays a critical role in signaling apoptosis and expression through gene transfer may be valuable in the treatment of a variety of apoptosis-related diseases such as cancer. However, constructing an adenoviral vector expressing a bax gene driven by a constitutive promoter has been difficult, presumably because of the gene's high proapoptotic activity. Here we report a system that induces the expression of the bax gene safely by adenovirus-mediated gene cotransfer. Briefly, the system involves an adenoviral vector containing a human bax cDNA driven by a synthetic promoter consisting of five GAL4-binding sites and a TATA box (GT). This vector expresses a minimal background level of bax protein in cultured mammalian cells thus preventing apoptosis of packaging cells, however, expression of the bax gene can be induced substantially in vitro and in vivo by transferring it into target cells along with an adenoviral vector expressing the transactivator, fusion protein GAL4/VP16. Extensive apoptosis was observed after induction of the bax gene both in cultured human lung carcinoma cells and in the livers of Balb/c mice. Our results suggest that this GAL4 gene regulatory system provides an alternative approach to constructing viral vectors that express potentially toxic genes. Gene Therapy (2000) 7, 75-79.

A physical map of the 20q12-q13.1 region associated with type 2 diabetes

Several recent genetic studies have suggested linkage of Type 2 diabetes (non-insulin-dependent diabetes mellitus) susceptibility to a region of chromosome 20q12-q13.1. To facilitate the identification and cloning of a diabetes susceptibility gene(s) in this region, we have constructed correlated radiation hybrid and YAC/BAC contig physical maps of the region. A high-resolution radiation hybrid map encompassing 9.5 Mb between the PLC and the CEBPB genes was constructed using 68 markers: 25 polymorphic markers, 15 known genes, 21 ESTs, and 7 random genomic sequences. The physical order of the polymorphic markers within this radiation hybrid map is consistent with published genetic maps. A YAC/BAC contig that gives continuous coverage between PLC and CEBPB was also constructed. This contig was constructed from 24 YACs, 34 BACs, and 1 P1 phage clone onto which 71 markers were mapped: 23 polymorphic markers, 12 genes, 24 ESTs, and 12 random genomic sequences. The radiation hybrid map and YAC/BAC physical map enable precise mapping of newly identified transcribed sequences and polymorphic markers that will aid in linkage and linkage disequilibrium studies and facilitate identification and cloning of candidate Type 2 diabetes susceptibility genes residing in 20q12-q13.1.

[GC-MS analysis of volatile constituents of rhizoma Heterosmilacis]

OBJECTIVE

To extract and analyze the volatile constituents from the dried rhizomes of Heterosmilax yunnanensis(A) and H. chinensis(B).

METHODS

Qualitative and quantitative analysis were made by GC-MS and GC.

RESULTS

Forty and forty-seven constituents were identified from A and B respectively, the identification rates being 74.85% and 81.26% respectively.

CONCLUSION

The volatile constituents of A and B are almost the same, but slightly different in content.

[The hydrogen bond between 5-(2-carboxyphenyl)-10, 15, 20-triphenylporphyrin and amino acid ester--study with UV-Vis titration and 1H-NMR]

The hydrogen bonds between the hydrogen of pyrrols in 5-(2-carboxyphenyl)-10,15,20-triphenylporphyrin and the oxygen of the carboxyl group of amino acid ester were confirmed by UV-Vis spectroscopic titration method and 1H-NMR. When amino acid ester was added to o-TPPCO2H solution in CHCl3, the Soret and Q and red-shifted dramatically and several isobestic points could be observed in UV-Vis spectra. In 1H-NMR, the signal of the hydrogen atoms of pyrrole in o-TPPCO2H (-2.78 ppm) decreased and a new signal in 0.260 ppm emerged, when o-TPPCO2H mixed with L-PheOEt at 1 : 1 (mol/mol).

[GC-MS analysis of essential oils from the roots of Saposhnikovia divaricata (Turcz.) Schischk, Libanotis laticalycina Shan et Sheh, Seseli yunnanense Franch. and Peucedanum dielsianum Fedde ex Wolff]

OBJECTIVE

To analyze the constituents of the essential oils from the roots of Saposhnikovia divaricata, Libanotis laticalycina, Seseli yunnanense and Peucedanum dielsianum.

METHOD

GC-MS method was used.

RESULT

58 compounds were identified.

CONCLUSION

To compare the constituents and their contents of 6 samples, 3 samples of S. divaricata growing in 3 places are similar, L. laticalycina, S. yunnanense and P. dielsianum are different from S. divaricata in varying degrees.

Induction of apoptosis and inhibition of tumorigenicity and tumor growth by adenovirus vector-mediated fragile histidine triad (FHIT) gene overexpression

We studied the effects of fragile histidine triad (FHIT) gene overexpression mediated by an adenoviral vector, Ad-FHIT, on cell proliferation, apoptosis, and cell cycle kinetics in human cancer cells and on tumorigenicity and tumor growth in nude mice. Overexpression of the FHIT gene significantly inhibited cell growth in various Ad-FHIT-transduced human lung cancer cells and head and neck carcinoma cells with FHIT gene abnormalities, but not in normal human bronchial epithelial cells. Fewer than 20% of cells in all Ad-FHIT-transduced cells survived at 7 days after transduction. Overexpression of the FHIT gene induced cell apoptosis and altered cell cycle processes. The apoptotic cell population markedly increased, and cells accumulated in S phase after Ad-FHIT transduction. The tumorigenicity of human H1299 lung cancer cells transduced by Ad-FHIT, in comparison with that of the control transductants and untreated cells, was eliminated in vivo. Subcutaneous tumor growth in nude mice who received intratumoral injections of Ad-FHIT, at a total dose of 3 x 10(10) plaque-forming units/tumor for H1299 tumors and 4 x 10(10)/tumor for A549 tumors, were suppressed by more than 85% and 90%, respectively, compared with that in nude mice who received injections of empty vector at the same dose or with PBS alone. Together, our results suggest that the FHIT gene, when delivered at high efficiency by a recombinant adenoviral vector, functions as a tumor suppressor gene both in vitro and in vivo.

Free radical activity, antioxidant enzyme, and glutathione changes with muscle stretch injury in rabbits

The present study investigated changes in rate of free radical production, antioxidant enzyme activity, and glutathione status immediately after and 24 h after acute muscle stretch injury in 18 male New Zealand White rabbits. There was no change in free radical production in injured muscles, compared with noninjured controls, immediately after injury (time 0; P = 0.782). However, at 24 h postinjury, there was a 25% increase in free radical production in the injured muscles. Overall, there was an interaction (time and treatment) effect (P = 0.005) for free radical production. Antioxidant enzyme activity demonstrated a treatment (injured vs. control) and interaction effect for both glutathione peroxidase (P = 0.015) and glutathione reductase (P = 0.041). There was no evidence of lipid peroxidation damage, as measured by muscle malondialdehyde content. An interaction effect occurred for both reduced glutathione (P = 0.008) and total glutathione (P = 0.015). Morphological analysis (hematoxylin and eosin staining) showed significant polymorphonuclear cell infiltration of the damaged region at 24 h postinjury. We conclude that acute mechanical muscle stretch injury results in increased free radical production within 24 h after injury. Antioxidant enzyme and glutathione systems also appear to be affected during this early postinjury period.

[Studies on tailed metalloporphyrin coordination compounds. IX. Synthesis of tailed porphyrin with covalently linked phenylalanine and its fluorescence property]

A new tailed porphyrin with covalently linked phenylalanine 2 and its zinc complex 3 were synthesized. Intramolecular energy transfer (from singlet excited phenylalanine to porphyrin) was observed in compound 2 and 3. The influence of coordination chemistry factor on the fluorescence of porphyrin was also discussed.

Reduced toxicity, attenuated immunogenicity and efficient mediation of human p53 gene expression in vivo by an adenovirus vector with deleted E1-E3 and inactivated E4 by GAL4-TATA promoter replacement

A recombinant adenovirus with deleted E1 and E3, and E4-inactivated by replacing the E4 promoter with a synthetic promoter composed of a minimal TATA box and five consensus yeast GAL4-binding site elements was developed and used to express the human tumor suppresser gene p53. The toxicity and immunogenicity of this vector and vector-mediated p53 gene expression in vivo were studied in immunocompetent C3H and C57BL/6 mice. Expression of the late viral gene product, hexon protein, was observed in C3H and C57BL/6 mice injected with E4 wild-type adenovirus constructs Adv-cmv-beta-Gal (BG), Adv-cmv-hp53 (WT), and empty E1- vector Adv-E4 (EW) 3 to 28 days after injection, but was undetectable in mice treated with E4 modified empty E1- vector Adv-GAL4 (EG) or Adv-cmv-hp53-GAL4 (G4). Expression of the p53 gene was observed in both WT- and G4-injected C3H and C57BL/6 mouse livers from days 3 to 28. Ten weeks after injection, p53 gene expression was still detected in G4-treated C57BL/6 mice at similar levels, but was not detectable in WT-treated mice. Vector-induced liver toxicity was evaluated by analyzing serum transaminases (SGOT and SGPT) activities. In all cases, SGOT and SGPT activities were markedly decreased in EG-treated C3H and C57BL/6 mice compared with those in EW-treated mice on days 3, 7 and 14 after injection. In C57BL/6 mice, the total anti-adenoviral CTL activities were two- to three-fold higher in animals treated with EW vector than in those treated with EG vector. These results suggest that inactivation of the E4 promoter efficiently diminished the viral replication and the late viral gene expression, reduced host immune response and consequently reduced toxicity and prolonged the duration of transgene expression in vivo.

[The visible spectra study of the conformation equilibrium of iron-metal-free porphyrin dimers]

A series of iron(III)-metal-porphyrin dimers linked with flexible alkoxyl chain at para position of two phenyl rings have been synthesized and characterized. An equilibrium of two conformations of porphyrin dimers (open and closed) has been studied by visible spectra. The intensity of absorption band 680 nm relates to equilibrium of two conformations. With the increase of the length of the alkoxyl chain,the closed conformation forms more easily. With the addition of axial ligand, the ferric ion of the dimers tends to bind with imidazole, and the intensity of the band 680 nm gradually decreases and disappears.

[Association of glucokinase gene with gestational diabetes mellitus in Chinese]

OBJECTIVE

To evaluate the role of glucokinase(GCK) gene in the pathogenesis of gestational diabetes mellitus (GDM) in Chinese.

METHODS

Two microsatellite polymorphisms, GCK1 and GCK2 which located at approximately 10 Kb 3' and 6 Kb 5', respectively, of the human glucokinase gene on chromosome 7p13, were genotyped in 40 unrelated gestational diabetics and 43 controls.

RESULTS

Four alleles (A, B, C, D) and seven genotypes were identified at the GCK1 locus. There was no significant difference in allele and genotype frequency between GDM and control groups at the GCK1 locus. For GCK2, four alleles(1,2,3,4) and eight genotypes were detected. When compared with control subjects, the GDM group had a much less frequency of the allele 2 (51.3% vs 69.8%, chi 2 = 5.965, P = 0.015), and a much more frequency of allele 3(31.3% vs 17.4%, chi 2 = 4.321, P = 0.038). Nine haplotypes of GCK1 and GCK2 were observed and haplotype B/2 was much less in GDM group(1.9% vs 19.4%, RR = 0.078 6, P = 0.003). Among the GDM patients, comparing with carriers of other alleles, the carriers of allele 3 of GCK2 locus had significantly elevated fasting and 2 hour's blood glucose levels during OGTT, and their insulin levels at 2nd and 3rd hour during the OGTT test were significantly decreased. Our results suggest that GCK gene was associated with Chinese GDM, and haplotype of GCK1/GCK2 B/2 was a protective factor for GDM.

Effects of endoglycoceramidase or D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol on glucose uptake, glycolysis, and mitochondrial respiration in HL60 cells

The glycosphingolipid content of HL60 cells was reduced by endoglycoceramidase, an enzyme which specifically hydrolyzes glycosphingolipids on the cell surface, or by D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, an inhibitor which specifically reduces the activity of UDP-glucose:ceramide glucosyltransferase. Reduction of the glycosphingolipid content by both reagents resulted in enhancement of glucose uptake and glycolysis. Neither of these effects was observed in the presence of cytochalasin B, an inhibitor of facilitated glucose transport. The uptake of radiolabeled 3-O-methylglucose by the cells was not affected by treatment with either of the reagents, indicating no activation of the glucose transporter. On the other hand, both reagents decreased the level of ATP and CO2 production. The molecule mediating these effects appeared to be ceramide, since both treatments actually increased the intracellular ceramide content, and the cell-permeable short-chain ceramide N-acetylsphingosine, but not sphingosine, sphinganine, or palmitic acid, mimicked the effects of both reagents to comparable extents. Finally, the function of electron transport in isolated mitochondria fractions was found to be reduced by treatment of the cells with N-acetylsphingosine. These results strongly suggest that ceramide may affect mitochondrial respiration.

[Sulfonylurea receptor gene polymorphism is associated with non-insulin dependent diabetes mellitus in Chinese population]

OBJECTIVE

To test the role of Sulfonylurea receptor gene(SUR) in the pathogenesis of NIDDM in Chinese population.

METHODS

We studied the polymorphisms of the SUR gene in intron 24 and exon 22 by polymerase chain reaction(PCR) and appropriate restriction enzyme (PCR-RFLP) in 86 NIDDM patients with at least two first degree diabetic relatives and 148 normal control subjects.

RESULTS

The frequency of "c" allele of intron 24 in NIDDM patients was significantly increased as compared with that in the control subjects (68.02% vs. 55.41, P = 0.007), and the frequency of the "cc" genotype of intron 24 in the NIDDM group was also significantly higher than that in the control group (41.86% vs. 27.7%, P = 0.013, OR = 4.39, CI: 1.52-12.66). The polymorphism of exon 22 described in the Caucasian population was not detected.

CONCLUSION

The association of the polymorphism of SUR gene with NIDDM in different races suggests that the SUR gene or nearby gene may play an important role in the genetic susceptibility of NIDDM.

Prednisone and low-dose activated prothrombin complex concentrates for FVIII inhibitor in nonhaemophilic patients

Eight nonhaemophilic patients with factor VIII (FVIII) inhibitors were reported. There was no difference in sex distribution. Median age at diagnosis was 62 years (ranging from 14 to 73 years). No associated disorders were revealed and all the patients were presented with severe muscular or arthral bleeding. Inhibitor titre was measured by the Bethesda method, which were 6.4, 126.0, 155.0, 4.8, 56.0, 13.5, 35.0 and 150.0 BU mL-1, respectively, at diagnosis. FVIII:C levels were less than 1 U dL-1 in seven patients and less than 2 U dL-1 in one patient. The median vWF:Ag level was 210% (ranging from 80% to 340%). All the patients had good response to activated prothrombin complex concentrates for acute bleeding episodes and prednisone for inhibitor elimination. Inhibitors completely eliminated in seven patients within a follow-up duration over 1 year, and one patient died of intracranial haemorrhage when her inhibitor titre decreased to 4.5 BU mL-1 and FVIII:C increased to 21 U dL-1.

A synthetic human Agouti-related protein-(83-132)-NH2 fragment is a potent inhibitor of melanocortin receptor function

Chemical synthesis of Agouti proteins - Agouti and Agouti-related proteins - is complicated by their large size and by multiple cysteine residues located in the carboxyl terminal regions. Three human Agouti-related protein (AGRP) fragments, two of which correspond to a proposed endoprotease cleavage site between amino acids 82 and 83, were synthesized and tested for anti-melanotropic activity using Xenopus laevis dermal melanophores. Amino-terminal fragments AGRP(25-51) and (54-82) were devoid of significant antagonist activity, whereas the amidated carboxyl-terminal AGRP fragment (83-132)-NH2 was potently active with an inhibitory equilibrium dissociation constant (Ki) of 0.7 nM. The ability to synthesize functionally active AGRP should help unravel its role in the central nervous system and its unusual properties with respect to interaction with the melanocortin family of G-protein coupled receptors.

Gender-specific association of M235T polymorphism in angiotensinogen gene and diabetic nephropathy in NIDDM

This study examined the association between the development of nephropathy in non-insulin-dependent diabetes mellitus (NIDDM) patients and M235T polymorphism in the angiotensinogen gene. White NIDDM patients with diabetic nephropathy (case subjects, n = 117) and patients without any evidence of nephropathy and > or = 10 years of NIDDM (control subjects, n = 125) were selected from among patients of the Joslin Diabetes Center and examined. In addition to a standardized examination, blood was drawn for DNA and determination of M235T genotypes at the angiotensinogen locus. For the angiotensinogen gene, the frequency of the genotype 235T/235T, known to be associated with essential hypertension, was higher among case subjects with nephropathy than in control subjects without this complication. This difference, expressed as the odds ratio for nephropathy among 235T/235T homozygotes in comparison with all other genotypes, was 2.2 (95% confidence interval, 1.1 to 4.4). The difference, however, was confined to men (odds ratio, 4.8; 95% confidence interval, 1.5 to 14.9), with the distribution of genotypes in case and control subjects being equal among women (odds ratio, 1.1). DNA polymorphism M235T in the angiotensinogen gene, which is associated with higher expression of this gene, contributes to the risk of diabetic nephropathy in NIDDM men but not in women.

Evaluation of GAL4/TATA in vivo. Induction of transgene expression by adenovirally mediated gene codelivery

A synthetic GAL4-responsive promoter consisting of five GAL4-binding sites and a TATA box (GAL4/TATA) was evaluated for its transcriptional activity in an adenoviral backbone using luciferase as the reporter. Basal luciferase activities in vitro were the same for cells infected with either adenovirus-containing luciferase cDNA driven by GAL4/TATA (Ad/GT-Luc) or adenovirus-containing luciferase cDNA not driven by a promoter (Ad/PO-Luc). In vitro induction of GAL4/TATA by coinfection of cells with adenovirus expressing the GAL4/VP16 fusion protein (Ad/3-phosphoglycerate kinase (PGK)-GV16) was dose-dependent and reached as high as 4 x 10(4)- to 9 x 10(4)-fold above basal levels when GAL4/TATA and GAL4/VP16 were delivered at a ratio of 10:1. In vivo studies in Balb/c mice showed no detectable luciferase activities in liver or other tissues examined in mice infused with either Ad/GT-Luc or Ad/PO-Luc. High levels of luciferase activity were, however, elicited when animals were infused with Ad/GT-Luc and Ad/PGK-GV16. Together, these results suggest that combination of the GAL4 gene regulatory system with adenovirally mediated in vivo gene delivery may be applicable to the in vivo evaluation of promoter activities and in vivo targeting of gene expression.

Suppression of the immune response to an adenovirus vector and enhancement of intratumoral transgene expression by low-dose etoposide

Adenoviral vectors are commonly used in gene therapy trials because of their efficiency in gene transfer. However, their use is limited by cellular and humoral immune responses that result in temporary transgene expression and reduced efficacy of repeated vector administration. We hypothesized that certain oncolytic agents commonly used to treat cancer patients could suppress the immune response to adenoviral vectors, and enable repeated adenovirus-mediated cancer gene therapy. Etoposide and cyclophosphamide were tested for their ability to suppress the humoral and cellular immune responses to an adenoviral vector in immunocompetent C3H mice. Intratumoral transgene expression was monitored in adenovirus-immunized animals treated with etoposide or cyclophosphamide. Neutralizing antibodies to adenovirus and cytotoxic T lymphocyte (CTL) lysis of virally transduced cells were significantly suppressed in mice treated with etoposide at 2 or 10 mg/kg/day or cyclophosphamide at 10 mg/kg/day compared with untreated mice (P < 0.05). Significantly larger areas of gene transduction were observed in treated animals compared with untreated mice or the mice treated with cyclophosphamide at 2 mg/kg/day (P < 0.05). Our results suggest that repeated adenovirally mediated gene therapy is achievable in cancer patients who are concurrently undergoing treatment with chemotherapy.

A packaging system for SV40 vectors without viral coding sequences

SV40 vectors have been used as expression vectors for mammalian cells since the early 1980s. More recently, they have been used as gene transfer vectors in mice and in human peripheral blood cells. Here we described a system for packaging SV40 vectors without viral coding sequences. Recombinant adenovirus-expressing SV40 capsids can effectively package plasmids that contain the SV40 replication origin. The final yield of infectious SV40 vector is about 3 x 10(5), with a SV40 to adenoviral vector ratio of about 1000:1. Helper adenoviruses can be effectively heat-inactivated with no effect on the infectivity of SV40 vectors.

Developmentally regulated O-acetylated sialoglycans in the central nervous system revealed by a new monoclonal antibody 493D4 recognizing a wide range of O-acetylated glycoconjugates

We have previously detected an alkali-labile and developmentally regulated antigen in rat embryonic cerebral cortex, which may be 9-O-acetylsialylated GT3 ganglioside (Hirabayashi Y, Hirota M, Suzuki Y, Matsumoto M, Obata K, Ando S (1989) Neurosci Lett 106:193-98). In this study we established a mouse monoclonal antibody, 493D4, that recognizes 9-O-acetyl GT3 ganglioside, but not non-O-acetyl gangliosides. This antibody also reacted with 9-O-acetyl GD3 to a much lesser extent. By using this antibody, we found that O-acetyl GT3 as well as O-acetyl GD3 were expressed strongly in fetal murine cerebral cortex and decreased to an undetectable level after birth. With the assistance of TLC-immunostaining using 493D4 together with Q-Sepharose column chromatography, O-acetyl gangliosides of bovine brain were purified and the structural analysis showed the presence of O-acetyl GD3, O-acetyl LD1, O-acetyl GD2 and O-acetyl GD1b in the adult brain as extremely minor components. Interestingly, the antibody 493D4 could detect O-acetyl sialoglycoproteins in rat brain tissues. One of the major immunoreactive proteins was shown to be synaptophysin, an integral membrane protein specifically present in synaptic vesicles. This monoclonal antibody was therefore useful for sensitive detection of both O-acetylated gangliosides and glycoproteins with O-acetylated sialic acids.

[Pharmacognostical identification of Anoectochilus roxburghii]

This paper reported the pharmacognostical identification on characters, microscopic characteristics and TLC of the Anoectochilus roxburghii (Wall.) Lindl., and compared with different resouce samples. The results may provide reference for its identification.

Calmodulin-dependent protein kinase II mediates signal transduction in apoptosis

The present studies describe a new function for calmodulin-dependent protein kinase II (CaM-KII) in signal transduction leading to apoptosis. Both tumor necrosis factor alpha (TNF) and UV light rapidly stimulated Ca2+-independent activity of CaM-KII in the monocytic leukemia, U937. Two mechanistically different inhibitors of CaM-KII blocked activation of CaM-KII and prevented DNA fragmentation and death. Activation of CaM-KII during apoptosis and inhibition of DNA fragmentation by the two CaM-KII inhibitors were reproduced in several other lines including KGla, HL-60, and YAC-1. However, K562, which is relatively resistant to apoptosis induced by either TNF or UV light, did not activate CaM-KII in response to these stimuli. A variant derived from U937 that is resistant to TNF- or UV light-induced apoptosis also lacked a CaM-KII response. Activation of Cam-KII was blocked by two protease inhibitors, VAD-fmk and TPCK, but not by other inhibitors of serine proteases. Both inhibitors of CaM-KII and the protease inhibitors blocked activation of AP24, a serine protease originally isolated from apoptotic cells that induces DNA fragmentation in nuclei. Our evidence supports a model in which proteolytic activity functions upstream of CaM-KII. This kinase then leads to activation of AP24, which transmits signals to the nucleus to initiate DNA fragmentation.

[GC-MS analysis of constituents of essential oils from stems of Ephedra sinica Stapf, E. intermedia Schrenk et C.A. Mey. and E. equisetina Bge]

The essential oils from the dried stems of Ephedra sinica, E. intermedia and E. equisetina were analyzed by GC-MS qualitatively and GC quantitatively. One hundred and twenty-seven constituents were identified, l-alpha-terpineol (31.64%) in E. sinica, 1,4-cineole (12.80%) in E. intermedia and hexadecanoic acid (26.22%) in E. equisetina being the main constituents.

Impact of gate fan-in and fan-out limits on optoelectronic digital circuits

The impact of gate fan-in and fan-out limits on digital circuit delay is discussed with a set of benchmark circuits. This research presents the advantages of exploiting the ability of optoelectronic gates to perform both logic operations and optical interconnections with systematic optimization. It is possible for gate-level optical interconnected optoelectronic circuits to compete with their pure silicon counterparts in terms of the combinational circuit delay and system clock rate.

[GC-MS analysis of constituents of essential oil from twigs and leaves of Tamarix chinensis Lour]

The essential oil from the dried twigs and leaves of Tamarix chinensis was analyzed by GC-MS qualitatively and GC quantitatively. Sixty-three constituents were identified, which make up 81.76% of the oil. Hexadecanoic acid (22.22%) was the main constituent.

[Spectroscopic investigation of the properties of axial coordination of tailed metalloporphyrins]

The properties of axial coordination of nitrogenous ligands to four tailed metalloporphyrins, O-PyTPPFe ( III ) Cl, O-ImTPPMn ( III ) Cl, O-PyTPPMn ( III ) Cl and O-ImTPPFe ( III ) Cl, has been investigated by UV-Visible spectral techniques. The effects of terminal groups, solvents and metal center were examined and discussed.

New susceptibility locus for NIDDM is localized to human chromosome 20q

To test the hypothesis that a gene (or genes) in the "MODY1 region" of the long arm of chromosome 20 contributes to the development of NIDDM, we conducted linkage studies in 29 extended Caucasian families in which many members were affected with NIDDM. A total of 498 individuals, including 159 NIDDM patients with an average age at diagnosis of 47 years, were genotyped for eight highly polymorphic microsatellite markers spanning a 31-cM region on chromosome 20q12-13.1. Using affected sib-pair analysis, we obtained evidence suggesting linkage between NIDDM and markers D20S119, D20S178, and D20S197 (allele sharing identical-by-descent [IBD], 0.56 for all three; P = 0.005, P = 0.009, and P = 0.004, respectively). Multipoint nonparametric linkage (NPL) analysis also showed evidence for linkage of NIDDM with the same three markers. The evidence for linkage was much stronger (allele sharing IBD by affected sibpairs, 0.64 [P < 0.0001]; maximum NPL score, 3.3 [P = 0.009]) in the 14 families whose average age at diagnosis of NIDDM was above the median (47 years) for all families. In these 14 families, one particular allele of the microsatellite D20S197 was transmitted from heterozygous parents to NIDDM offspring more frequently than expected (P < 0.01). This indicates that the marker allele and the disease allele are in linkage disequilibrium, implying that they are in close proximity. Consequently, the recently identified MODY1 gene (hepatocyte nuclear factor 4) is an unlikely candidate gene for NIDDM in our families, since it is located about 8 cM centromeric of D20S197. In conclusion, we have identified a new region on chromosome 20q that contains one or more NIDDM genes distinct from the recently identified MODY1 gene.

[Detection of hepatitis A virus in environmental samples by coupled reverse transcription and polymerase chain reaction]

A direct reverse transcription coupled with polymerase chain reaction (RT-PCR) was used to detect HAV-seeded sea water, coastal sediment and Arca subcrenata, HAV strain treated by different kind of disinfection, and naturally occurring HAV in Arca subcrenata. The results showed that HAV could be detected in HAV-seeded sea water, coastal sediment and Arca subcrenata. HAV could also be detected in HAV strain disinfected by phenol, suggesting that inactive HAV could also show positive PCR. Only Arca subcrenata collected from Shanghai in 1988 showed positive result by RCR, but negative by immunofluorescence at the same time. This result demonstrated that HAV was not infectious owing to long time storage. The author's method has the advantage of involving fewer manipulations.

DNA measurement of overlapping cell nuclei in thick tissue sections

The paper describes an improved image analysis procedure for measuring the DNA content of cell nuclei in thick sections of liver tissue by absorption densitometry. Whereas previous methods only permitted the analysis of isolated nuclei, the new technique enables both isolated and overlapping nuclei to be measured. A 3D segmentation procedure determines whether each object is an isolated nucleus or a pair of overlapping nuclei; in the latter case the combined optical density is redistributed to the individual nuclei. A selection procedure ensures that only complete nuclei are measured. The method has been tested on specially-prepared Feulgen-stained 20micro sections of normal liver tissue. The overall distribution of the nuclear DNA measurements shows well-defined diploid and tetraploid peaks, with coefficient of variations of less than 10%. Similar distributions were obtained from both the isolated nuclei and overlapped nuclei sub-populations.

CREB proteins function as positive regulators of the translocated bcl-2 allele in t(14;18) lymphomas

The translocated and normal bcl-2 alleles in the DHL-4 cell line with the t(14;18) translocation were separated by pulsed field electrophoresis. An in vivo footprint over a cAMP response element (CRE) in the bcl-2 5'-flanking sequence was identified on the translocated allele. Electrophoretic mobility shift assays with the bcl-2 CRE demonstrated complexes with mobilities identical to those with a consensus CRE. UV cross-linking experiments revealed that proteins with molecular masses of 34, 43, and 67 kDa bound to the bcl-2 CRE site. Electrophoretic mobility shift assay with an antibody specific to the phosphorylated cAMP response-binding protein (CREB) demonstrated that phosphorylated CREB was present in DHL-4 cells. Treatment with phorbol 12-myristate 13-acetate (PMA) led to an increase in both the amount of phosphorylated CREB and the bcl-2 promoter activity. The response to PMA was dependent on an intact CRE site. The activity of the bcl-2 promoter was increased 20-fold in a construct with the immunoglobulin heavy chain enhancers, and mutation of the CRE site abolished most of the induction. The addition of PMA increased the activity of the bcl-2-immunoglobulin enhancer construct by 3.5-fold. Access to the CRE site is blocked in the silent normal bcl-2 allele, while CREB proteins bind to the site on the translocated allele. We conclude that the CRE site functions as a positive regulatory site for the translocated bcl-2 allele in t(14;18) lymphomas.

Characteristics of harringtonine-resistant human leukemia HL60 cell

AIM

To study the mechanisms of the resistance to harringtonine (Har) in the HL60 cells.

METHODS

Growth inhibition, karyotype analysis, flow cytometry, Western blotting and polymerase chain reaction.

RESULTS

The Har-resistant HL60 cell line, named HR20, showed cross resistance to homoharringtonine, doxorubicin, daunorubicin, vincristine, and colchicine. The growth doubling time and the cell numbers in G1 phase were increased. The accumulation of cellular daunorubicin in the resistant cells was obviously reduced, but distinctly increased by tetrandrine and verapamil. The numbers of telocentromeric chromosome increased and the chromosomal aberration more occured in the resistant cells. The resistant cells overexpressed multidrug resistant mdr-1 gene and P-glycoprotein 150 kDa.

CONCLUSION

The Har-resistant HL60 cell strain belonged to a multidrug resistance strain, overexpressing mdr-1 gene and P-glycoprotein.

[Quality standard of tanre kesou granules]

A TLC method was used in the identification of the following chemical consitituents of medicinal herbs in Tanre Kesou Granules: Radix Scutellariae, Bulbus Fritillariae Thunbergii, Pericarpium Citri Reticulatae and Fructus Aurantii Immaturus. The sample was purified through acidification with hydrochloric acid and extraction with ethyl acetatethe. The contents of baicalin in the preparation and Radix Scutellariae were determined by means of HPLC and TLC-densitometry. These methods fit for quality control of the preparation containing baicalin.

[Studies on the essential oils in Ligusticum chuanxiong Hort. of different habitats and species]

Constituents of the essential oils obtained from Chuanxiong, Yungxiong, Fuxiong, Xixiong and "Chuanxiong" of Japan were analysed by GC-MS. Ninety-six compounds including ligustilide, etc. were identified. Their percentages in the oils were given.

Tumor necrosis factor alpha increases tyrosine phosphorylation of a 23-kDa nuclear protein in U937 cells through ceramide signaling pathway

In many tumor cell lines, tumor necrosis factor alpha (TNF alpha) causes profound alterations in nucleus including chromatin condensation and DNA fragmentation. However the mechanism is largely unknown. Here we demonstrate that TNF alpha treatment of U937 cells increased tyrosine phosphorylation of a 23-kDa nuclear protein (P23) maximally by 13-fold, which occurred after 2.5 h treatment concomitantly with occurrence of DNA fragmentation. Tyrosine kinase inhibitor, herbimycin A, inhibited either tyrosine phosphorylation of P23 or DNA fragmentation, suggesting that the P23 phosphoprotein may be involved in the TNF alpha-induced changes in nucleus. Increase of intracellular Cer level by hydrolysis of cell surface SM with bacterial sphingomyelinase or addition of either C2-Cer or natural Cer also resulted in increase of P23 tyrosine phosphorylation, which was detectable at 1.5 h treatment and reached maximum after 2 h treatment, indicating that P23 phosphoprotein may be a downstream effector of Cer signaling pathway. Our data provide further evidence that Cer signaling pathway may mediate signal transduction of TNF alpha.

Inhibition of tumor necrosis factor alpha- and ceramide-induced internucleosomal DNA fragmentation by herbimycin A in U937 cells

In many tumor cell lines, tumor necrosis factor alpha (TNF alpha) causes apoptosis with characteristic internucleosomal DNA fragmentation. However, the mechanism is largely unknown. Here we examined the involvement of protein tyrosine kinases by using their inhibitors. Among various tyrosine kinase inhibitors tested, only herbimycin A was found to inhibit internucleosomal DNA fragmentation but not apoptotic morphological changes and cell death induced by TNF alpha in U937 cells. Herbimycin A was able to block DNA fragmentation when it was added to the cell culture as late as 1.5 h after TNF alpha treatment. These results demonstrate that herbimycin A selectively inhibits a later event involved in the process of apoptois that results in internucleosomal DNA fragmentation. Sphingomyelinase and ceramide (Cer) induced internucleosomal DNA fragmentation was also inhibited by herbimycin A, supporting the hypothesis that Cer may be a novel second messenger mediating the cytotoxic effect of TNF alpha.