Effect of angiotensin II on hematopoietic progenitor cell proliferation

Angiotensin II (AII) induced the proliferation of hematopoietic progenitor cells (HPC) isolated from murine bone marrow or human cord blood. The formation of colonies with more than 50 cells increased approximately five-sevenfold in cultures of murine lineage-negative (Lin(-)) bone marrow cells both in the presence (day 10) and absence (day 13) of colony-stimulating factors (CSF). This could be blocked with addition of Losartan, an antagonist of AIITR1. The increase in proliferation of early hematopoietic progenitors (Lin(-)Sca l(+) cells) by AII was approximately threefold and occurred only in the presence of CSF, suggesting that AII may affect mesenchymal stromal cells to induce CSF production and might directly affect early HPC. These in vitro studies were replicated with human HPC isolated from cord blood. AII also accelerated the proliferation and formation of colony-forming units (CFU)-granulocyte/erythroid/macrophage/megakaryocyte and CFU-granulocyte/macrophage colonies by CD34(+)CD38(-) enriched progenitors but only in the presence of CSF. Additional studies also indicated that AII can act to increase proliferation in suspension culture. Exposure of CD34(+) cells to AII in suspension culture, prior to placement in a semisolid medium with erythropoietin, increased the formation of colonies with more than 50 cells and erythroid progenitors approximately five- and 20-fold, respectively. Further, mRNA for the AT1a receptor was expressed by human bone marrow CD34(+)CD38(-) cells, CD34(+)CD38(-) cells, and lymphocytes, but not mature myeloid cells. Similarly, mRNA for the AT1a receptor was expressed on human stromal cell clones, offering further support to the hypothesis that AII acts partially through the mesenchymal compartment of the bone marrow. These data suggest that AII may be a factor which stimulates the proliferation of hematopoietic progenitors.

[Skeletal dysplasia and osteoporosis due to inadequate athletic]

Athletic load is an important factor that has an influence on the growth, development and mature of skeleton. In patients who had the functional disorder of hip joint resulting from hip diseases during their teen-ages, skeletal dysplasia and osteoporosis would occur. The present paper reported 30 cases of unilateral hip disorder. The patients were 20 men and 10 women whose age ranged from 2 to 20 years. The course of disease lasted 2 to 49 years. Their primary diseases included suppurant hip arthritis (16 cases), tuberculous arthritis of hip (10 cases), and others (4 cases). The follow-up study revealed fixed hip joint in 18 cases, positive Thomas sign in 22 cases, limited motion of hip joint in 12 cases, and unequal length of lower extremities in 25 cases; at the same time X-ray films showed ankylosis of hip at normal position in 10 patients, dislocation with ankylosis of hip in 13 patients, arthritic disorder of hip in 7 patients, skeletal dysplacia of ischium and pubis in 18 patients, and skeletal dysplasia of femur in 22 patients. All patients had osteoporosis. A discussion about the basic mechanism for skeletal dysplasia and osteoporosis following inadequate athletic load is presented. We believe that the skeletal dysplasia and osteoporosis in our group were caused by the diseases that led to inadequate athletic load. Therefore it is important to provide a thorough treatment and help the patients to their strength to be loaded in time.

Wild-type p53 suppresses angiogenesis in human leiomyosarcoma and synovial sarcoma by transcriptional suppression of vascular endothelial growth factor expression

Our recent studies (R. Pollock et al., Clin. Cancer Res., 4: 1985-1994, 1998; M. Milas et al., Cancer Gene Ther., in press, 2000) have shown that the restoration of wild-type (wt) p53 enhances cell cycle control in vitro and inhibits the growth of human soft-tissue sarcoma in severe combined immunodeficient mice. We hypothesized that the antitumor effect of wt p53 overexpression in sarcoma cells is attributable not only to enhanced cell cycle control but also to inhibition of angiogenesis. We evaluated the effect of restoring wt p53 function on angiogenesis in human soft-tissue sarcoma harboring mutant p53. Restoration of wt p53 expression in human leiomyosarcoma SKLMS-1 cells that contain mutant p53 markedly inhibited angiogenesis induced by tumor cells in vivo. Angiogenesis assays using an in vivo Matrigel plug assay demonstrated that less neovascularization in severe combined immunodeficient mice was observed with conditioned medium (CM) from human synovial sarcoma cells expressing wt p53 compared with CM from human synovial sarcoma cells expressing mutant p53. Microvessel density and microvessel counts were lower in tumor xenografts from cells containing wt p53 than in tumor xenografts from cells containing mutant p53. The growth and migration of murine lung endothelial cells were decreased when cells were treated with CM from sarcoma cells expressing wt p53 compared with CM from sarcoma cells expressing mutant p53. The introduction of wt p53 into sarcoma cells containing mutant p53 significantly reduced the expression of vascular endothelial growth factor (VEGF), which is a key mediator of tumor angiogenesis. Stimulation of endothelial cell migration by CM from cells expressing mutant p53 was significantly reduced after anti-VEGF neutralizing antibody was added to the CM. Using luciferase as the reporter of VEGF promoter activity, we found that wt p53 inhibited VEGF promoter activity in SKLMS-1 cells. Deletion analysis defined an 87-bp region (bp -135 to -48) in the VEGF promoter that is necessary for inhibiting VEGF promoter activity by wt p53. The transcription factor Sp1 may be involved in the repression of VEGF promoter activity by wt p53 in SKLMS-1 cells. These data indicated that wt p53 can suppress angiogenesis in human soft-tissue sarcomas by transcriptional repression of VEGF expression.

[Clinical controlled study of shenmai injection and aminophylline on diaphragm fatigue]

OBJECTIVE

To compare the therapeutic effect of Shenmai injection (SM) and aminophylline (AP) on diaphragm fatigue in chronic obstructive pulmonary disease (COPD).

METHODS

Sixty-four COPD patients with respiratory failure and diaphragm fatigue were randomly divided into 2 groups: (1) SM group (33 patients), treated with oxygen inhalation and anti-infection agents, and SM injection (SM 40 ml + 10% glucose 100 ml), (2) AP injection group (31 patients), treated with AP 0.25 g plus 10% glucose 100 ml, and the same comprehensive treatment. To investigate the initial time of diaphragm fatigue disappearance, the maintaining effect of 24 hours of drug administration, and the arterial blood gas analysis.

RESULTS

The effect in 30 min and maintaining effect in 24 hours in SM group were better than those in the AP group. In both groups, PaO2 increased and PaCO2 decreased.

CONCLUSION

The therapeutic effect of SM on COPD patients with respiratory failure and diaphragm fatigue was better than those of AP.

Angiotensin II increases host resistance to peritonitis

Studies by other laboratories have shown that angiotensin II (AII) can affect the function of cells which comprise the immune system. In the present study, the effect of AII on the function of peritoneal macrophages and peripheral blood monocytes was assessed. In vitro exposure (4 h prior to assay) of peritoneal macrophages from mice and rats to AII increased the percentage of cells that phagocytosed opsonized yeast and the number of yeast per macrophage. Furthermore, AII increased the respiratory burst capacity of peritoneal macrophages from mice and rats and peripheral blood mononuclear cells from humans. Because of these observations, the effect of AII on host resistance to bacterial infection was assessed. Intraperitoneal administration of AII was shown to increase host resistance (reduced abscess formation) in an animal model of bacterial peritonitis. Studies were then conducted to assess whether parenteral administration of AII, a clinically relevant route, could affect peritoneal host resistance in a manner similar to that observed after peritoneal administration. These studies showed that subcutaneous administration of AII throughout the postinfection interval increased the level of host resistance to bacterial peritonitis. Furthermore, in a study which compared AII and Neupogen, an agent approved for use for the reduction of febrile neutropenia after myeloablative therapy, daily subcutaneous administration of AII reduced abscess size and incidence, whereas Neupogen did not have any therapeutic benefit in this model. These data suggest that AII may be of therapeutic benefit as an immunomodulatory agent.

Sterol regulation of human fatty acid synthase promoter I requires nuclear factor-Y- and Sp-1-binding sites

To understand cholesterol-mediated regulation of human fatty acid synthase promoter I, we tested various 5'-deletion constructs of promoter I-luciferase reporter gene constructs in HepG2 cells. The reporter gene constructs that contained only the Sp-1-binding site (nucleotides -82 to -74) and the two tandem sterol regulatory elements (SREs; nucleotides -63 to -46) did not respond to cholesterol. Only the reporter gene constructs containing a nuclear factor-Y (NF-Y) sequence, the CCAAT sequence (nucleotides -90 to -86), an Sp-1 sequence, and the two tandem SREs responded to cholesterol. The NF-Y-binding site, therefore, is essential for cholesterol response. Mutating the SREs or the NF-Y site and inserting 4 bp between the Sp-1- and NF-Y-binding sites both resulted in a minimal cholesterol response of the reporter genes. Electrophoretic mobility-shift assays using anti-SRE-binding protein (SREBP) and anti-NF-Ya antibodies confirmed that these SREs and the NF-Y site bind the respective factors. We also identified a second Sp-1 site located between nucleotides -40 and -30 that can substitute for the mutated Sp-1 site located between nucleotides -82 and -74. The reporter gene expression of the wild-type promoter and the Sp-1 site (nucleotides -82 to -74) mutant promoter was similar when SREBP1a [the N-terminal domain of SREBP (amino acids 1-520)] was constitutively overexpressed, suggesting that Sp-1 recruits SREBP to the SREs. Under the same conditions, an NF-Y site mutation resulted in significant loss of reporter gene expression, suggesting that NF-Y is required to activate the cholesterol response.

[Factor XIIa-inhibited diluted thromboplastin time can reflect coagulation process]

OBJECTIVE

To establish a screening test that can reflect two stages of coagulation process.

METHODS

With FXII a being blocked, the effects of various dilution of thromboplastin on clotting time were observed. FX a activity was determined by chromogenic assay.

RESULTS

(1) At high concentration of thromboplastin, FXII a-inhibited diluted thromboplastin time (FXII ai DTT) of pooled normal plasma and FXI deficient plasma was very similar, but at low concentration, FXII ai DTT was in order of FVIII and FIX deficient plasma > FXI deficient plasma > pooled normal plasma. (2) FXI consumption by immunologic method induced FXII ai DTT of pooled normal plasma prolonged, and addition of FXI to FXI deficient plasma shortened FXII ai DTT. (3) Alpha-thrombin blocked by hirudin at different time (10 - 80 seconds) resulted in decreased FXa generation, and the earlier the block, the more the decrease. Under the same condition, the amount of FXa generation was in order of platelet-rich plasma > platelet-poor plasma > FXI deficient plasma.

CONCLUSION

(1) Our data support the two-stage hypothesis and confirm the important role of FXI in the amplification stage. (2) FXII ai DTT as a screening test for coagulation process may be practicable.

RAR and RXR expression by Kupffer cells

Retinoids are known to modulate macrophage differentiation, proliferation, and function including cytokine gene expression. However, signaling of retinoic acid (RA), a biologically active metabolite of vitamin A, in Kupffer cells has not been characterized. This study reports mRNA expression by rat Kupffer cells of RA receptor (RAR) and retinoid X receptor (RXR) subtypes and their binding activities to the RA responsive element (RARE) or retinoid X responsive element (RXRE). Total RNA and nuclear proteins were extracted from Kupffer cells immediately following isolation from livers of normal male Wistar rats. Competitive PCR demonstrated relative mRNA expression of RAR and RXR subtypes in the order of beta>alpha>gamma for and alpha>beta>gamma, respectively. It also demonstrated that the RXR alpha and beta mRNA levels were 5- to 10-fold higher in Kupffer cells than in hepatic stellate cells while RAR mRNA expression was shown to be similar for all the subtypes in both cell types. Gel mobility shift assays of nuclear extracts with labeled RARE and RXRE probes showed distinct binding activities for both responsive elements, which were effectively displaced with cold probes in excess but not with an unrelated oligonucleotide. A supershift assay with an antibody against RARalpha or RXRalpha has confirmed the contribution of both receptors to RARE binding and that of the RXRalpha to RXRE binding activity. These results represent the first demonstration of RA signaling at the nuclear level in Kupffer cells.

The change of interleukin-6 and tumor necrosis factor in patients with obstructive sleep apnea syndrome

The levels of lipopolysaccharide (LPS)-induced interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) expression in culture of peripheral blood mononuclear cells (PBMC) and the plasma levels of IL-6 and TNF-alpha in the patients with obstructive sleep apnea syndrome (OSAS) were measured and the relationship between OSAS and IL-6 or TNF-alpha expression studied. Both IL-6 and TNF-alpha were detected by using ELISA in 22 patients with OSAS and 16 normal controls. The levels of LPS-induced IL-6 (787.82 +/- 151.97 pg/ml) and TNF-alpha (4165.45 +/- 1501.43 pg/ml) expression in the supernatant of the culture of PBMC and plasma level of IL-6 (50.67 +/- 4.70 pg/ml) and TNF-alpha (299.09 +/- 43.57 pg/ml) in the patients with OSAS were significantly higher than those in the normal controls (in the supernatant of the culture of PBMC: 562.69 +/- 197.54 pg/ml and 1596.25 +/- 403.08 pg/ml respectively; in the plasma; 12.69 +/- 2.75 pg/ml and 101.88 +/- 21.27 pg/ml respectively). There were significantly positive correlation between the levels of IL-6 and TNF-alpha and the percentage of time of apnea and hyponea, as well as the percentage of time spending at SaO2 below 90% in the total sleep time. It was concluded that LPS-induced IL-6 and TNF-alpha levels as well as plasma IL-6 and TNF-alpha levels in the patients with OSAS were up-regulated, which may be associated with the pathogenesis of OSAS.

Obstructive jaundice caused by tumor emboli from hepatocellular carcinoma

Hepatocellular carcinoma (HCC) presenting as obstructive jaundice due to intrabile duct tumor growth is being reported with increasing frequency. We describe our clinical experiences and evaluate the results of different operative procedures for this disease. A retrospective study was undertaken to review 18 patients with obstructive jaundice by tumor emboli from HCC during a 15-year period of time. We reviewed clinical features, types of operative procedures, operative findings, and survival in the patients. All patients on initial examination had recurrent episodic jaundice or cholangitis. Types of surgical procedures were choledochotomy with T-tube drainage alone in nine patients, choledochotomy with T-tube drainage followed by hepatectomy in six, and T-tube drainage followed by transcatheter hepatic arterial chemoembolization in the remaining three patients. Liver cirrhosis was the associated disease in 15 (83.3%). There were three postoperative deaths (16.7%). The mean survival time for nine patients with external drainage alone was 4.5 months. For the three patients with T-tube drainage and transcatheter hepatic arterial chemoembolization, mean survival time was 11 months. Six patients who had undergone hepatectomy had a better postoperative survival time, with 1 surviving for more than 3 years and another alive for 70 months, without evidence of recurrence at the moment. Jaundice is not necessarily a harbinger of advanced disease and a contraindication for surgery. Managed properly, these patients will have satisfactory palliation and occasional cure.

Activation of CD4 T cells by somatic transgenesis induces generalized immunity of uncommitted T cells and immunologic memory

Cellular immune responses were analyzed in vivo after a single intraspleen inoculation of DNA coding for a 12-residue Th cell determinant associated with a 12-residue B cell epitope, a process termed somatic transgene immunization. We show that CD4 T cells are readily activated and produce IL-2, IFN-gamma and IL-4, characteristics of an uncommitted phenotype. Linked recognition of the two epitopes coded in the same transgene promoted IgM-IgG1 switch and enhanced the total Ab response but had no effect on IgG2a Abs. Although originating in the spleen, T cell responsiveness was found to spread immediately and with similar characteristics to all lymph nodes in the body. A single inoculation was also effective in establishing long term immunologic memory as determined by limiting dilution analysis, with memory T cells displaying a cytokine profile different from that of primary effector T cells. These studies provide evidence that by initiating immunity directly in secondary lymphoid organs, an immune response is generated with characteristics that differ from those using vaccines of conventional DNA or protein in adjuvant administered in peripheral sites. Somatic transgene immunization can therefore be used to probe T cell responsiveness in vivo and represents a tool to further understanding of the nature of the adaptive immune response.

[Pre- and post-operative changes in serum levels of glycocholic acid and 3,5,3'-triiodothyronine and their clinical significance in patients with cholelithiasis]

Pre- and post-operative changes of serum glycine-conjugated cholic acid (CG) and 3,5,3'-triiodothyronine (T3) levels were observed in twenty-two patients with cholelithiasis. The increase of the levels of serum CG varied with the patients; the highest levels were seen in patients with cirrhosis. After operation, the levels of serum CG and T3 were decreased significantly in patients without cirrhosis. There was positive correlation between serum CG and T3 (r = 0.4667, P < 0.01). It is indicated that the lowering of serum CG after operation may be related to the lowering of serum T3; the significant increase of serum CG level is useful to the diagnosis of liver cirrhosis, which is more sensitive than Type B ultrasonography or routine examination of liver function.

[Effect of Ganoderma japonicum (Fr.) Lloyd mixture on experimental thrombosis]

The therapeutic effect of Ganoderma japonicum(Fr.) Lloyd mixture on thrombosis and its mechanism were studied. The results showed that Ganoderma japonicum(Fr.) Lloyd mixture inhibited thrombus formation in vitro and in vivo, the thrombus weight and length formed in the rabbit common carotid artery and external jugular vein were significantly decreased in the experimental group compared with the control (P < 0.01). The results suggest that Ganoderma japonicum(Fr.) Lloyed mixture has anti-thrombotic effect, blood coagulation and platelet activation were inhibited, and the ability of vascular endothelial cells against the process of thrombosis was enhanced.

[Effects of aprotinin on heparinized whole blood activated clotting time and whole blood prothrombin time]

When aprotinin is used during cardiopulmonary bypass, there is a prolongation of the activated clotting time (ACT), which is used to monitor heparinization. The aim of this study was to observe the effects of aprotinin and heparin on whole blood ACT and whole blood prothrombin time (BPT). The results showed that when kaolin was used as the contact activator, the intrinsic clotting system was also inhibited by aprotinin, the observed ACTs with various dose aprotinin and concomitant heparin were significantly prolonged (Q = 0.757, P < 0.01). There was a dose-dependent prolongation of BPT by heparin (r = 0.985, P < 0.01). However, the heparin-mediated prolongation of BPT was not enhanced by aprotinin. The authors conclude that aprotinin prolongs heparinized whole blood activated clotting time but was not whole blood prothrombin time.

Identification of thyroid hormone response elements in the human fatty acid synthase promoter

To investigate the regulation of the human fatty acid synthase gene by the thyroid hormone triiodothyronine, various constructs of the human fatty acid synthase promoter and the luciferase reporter gene were transfected in combination with plasmids expressing the thyroid hormone and the retinoid X receptors in HepG2 cells. The reporter gene was activated 25-fold by the thyroid hormone in the presence of the thyroid hormone receptor. When both the thyroid hormone and the retinoid X receptors were expressed in HepG2 cells, there was about a 100-fold increase in reporter gene expression. 5'-Deletion analysis disclosed two thyroid hormone response elements, TRE1 (nucleotides -870 to -650) and TRE2 (nucleotides -272 to -40), in the human fatty acid synthase promoter. The presence of thyroid hormone response elements in these two regions of the promoter was confirmed by cloning various fragments of these two regions in the minimal thymidine kinase promoter-luciferase reporter gene plasmid construct and determining reporter gene expression. The results of this cloning procedure and those of electrophoretic mobility shift assays indicated that the sequence GGGTTAcgtcCGGTCA (nucleotides -716 to -731) represents TRE1 and that the sequence GGGTCC (nucleotides -117 to -112) represents TRE2. The sequence of TRE1 is very similar to the consensus sequence of the thyroid hormone response element, whereas the sequence of TRE2 contains only a half-site of the thyroid hormone response element consensus motif because it lacks the direct repeat. The sequences on either side of TRE2 seem to influence its response to the thyroid hormone and retinoid X receptors.

Experimental study on pathogenicity of precore mutants in Hepadnaviridae

OBJECTIVE

To study the replicative competency and pathogenicity of precore gene mutants of duck hepatitis B virus (DHBV) in the duck model.

METHODS

Three site-directed point mutations in the precore region of cloned DHBV were constructed. Head-to-tail dimers were formed. The three plasmids were named: pEDM1-2 (initiation codon ATG mutated to TTG), pEDM2-2 (an "A" was inserted down stream of codon 12, leading to frame shift in the distal end of precore region), pEDM3-2 (codon 38 was changed from TAT to TAA, leading to a stop codon at the 3'-end). Mutants and wild-type cloned DNA dimers were first separately used to transfect LMH cells (a chicken hepatoma cell line) and viruses were collected from supernatant and used to infect 6 one-day-old ducklings per group. Serum duck hepatitis B surface antigen (DHBsAg) and DHBV DNA were assayed. Six weeks after infection, ducks were killed and liver tissues were studied for histopathological changes.

RESULTS

After transfection, pEDM1-2, pEDM2-2 and pEDM3-2 expressed similar level of DHBsAg. Replication of pEDM1-2 and pEDM3-2 was similar to that of the wild type clone, while pEDM2-2 replicated at a significantly decreased level. Infection study employing the supernatant of transfected cells was as follows: pEDM1-2 infected 5/6 ducklings, pEDM2-2 non infected, pEDM3-2 infected 2/6 ducklings, wild type virus infected 6/6 ducklings. Positive serum samples from both pEDM1-2 and pEDM3-2 were at a lower serum DHBV level compared to that of the wild type virus. Pathological changes were more significant in pEDM3-2 infected duck livers, with numerous inflammatory cells in portal tract and infiltration into parenchyma.

CONCLUSIONS

Mutations in the initiating codon or generation of a stop codon at the 3'-end of the precore region resulted in decreased replication competency of DHBV, while frame-shift mutation of the precore region, covering the epsilon encapsidation signal abolished the replication of DHBV. When the mutants replicated in hosts, more severe pathological changes were observed in ducks infected with mutant harboring a stop codon at the 3'-end. Data suggest that replicative-competent DHBV precore mutant can be more pathogenic than wild-type DHBV.

Durable immunity and immunologic memory to a parasite antigen induced by somatic transgene immunization

Somatic transgene immunization (STI) is an alternative approach to immunization mediated by inoculation of plasmid DNA. In the experiments presented here we show that inoculation of plasmid DNA carrying an immunoglobulin heavy chain gene under the control of tissue-specific regulatory elements, leads to immunity and persistent immunologic memory against a peptide epitope encoded in the third complementarity-determining region. The epitope consists in three repeats of the tetrapeptide Asn-Ala-Asn-Pro (NANP) and is the immunodominant B cell epitope expressed at the surface of Plasmodium falciparum malaria parasite. When inoculated directly in the spleen the plasmid DNA initiated a specific anti-NANP response which lasted for 2 years. During the initial phase of priming the anti-NANP response was higher than that induced by immunization with recombinant protein in immunologic adjuvants. The establishment of immunologic memory was probed by single booster injection at various times after priming. We found that STI induces persistent immunologic memory up to 2 years. The immunologic characteristics of this new model are examined with respect to the requirement for the induction of B cell memory.

Effect of administration of malathion for 90 days on macrophage function and mast cell degranulation

Previous studies have shown that acute, oral administration of malathion modulated the humoral immune response to T cell-dependent antigen, mitogenic responses, macrophage function and mast cell degranulation. In this report, the effects of malathion administration for 90 days on macrophage function, as measured by respiratory burst capacity, phagocytic capability and the production of cathepsin D, and mast cell integrity were assessed. A dose-dependent increase in respiratory burst activity was observed at all doses tested. The production of cathepsin D was elevated at doses of 1 mg/kg/day malathion or greater. The phagocytic capability of peritoneal macrophages was elevated at the dose of 0.1 mg/kg/day, but was suppressed at higher doses. The effect of oral administration of malathion for 90 days on the degranulation of mast cells, in both organs (skin and uterus) and peritoneal lavage fluid, was also assessed. Degranulation (both severe and slight) of mast cells from the skin and peritoneum was observed at a dose of 1.0 mg/kg/day or greater. In addition, the percentage of mast cells that were undegranulated was decreased. In the skin, but not the peritoneum, these effects were dose-dependent. In the uterus, the percentage of mast cells that were undegranulated was decreased and severely degranulated was increased at a dose of 0.1 mg/kg/day or greater. These data indicate that repeated administration of malathion increased macrophage function and led to mast cell degranulation at doses as low as 0.1 mg/kg/day for 90 days.

Engineering vaccines with heterologous B and T cell epitopes using immunoglobulin genes

Antibodies engineered in their variable domain to express epitopes of heterologous antigens-antigenized antibodies-function as immunogens. Only the third complementarity-determining region (CDR3) of the H chain has been used as the site of epitope expression, as this loop has the highest natural variability in length and amino acid composition. We demonstrate that the CDR2 can be engineered to express a 12-amino acid peptide, which is a T-cell determinant that enhances the response to a B-cell epitope peptide of Plasmodium falciparum expressed in the CDR3 of the same variable domain. Mice with this gene inoculated into the spleen mounted an antibody response against the B-cell epitope higher than mice receiving the gene coding for the B-cell epitope only. In vitro studies established that the two epitopes were independently immunogenic in vivo.

Effect of acute administration of malathion by oral and dermal routes on serum histamine levels

Previous studies have shown that acute, oral administration of malathion increased the generation of a humoral immune response, stimulated macrophage function and caused mast cell degranulation and histamine release. In this study, the effect of acute administration of various doses of malathion via oral and dermal routes to mice and rats on serum levels of histamine was evaluated. Oral administration of malathion to mice led to an increase in the level of serum histamine 4 and 8 h after administration. At 4 h after administration, the peak in serum histamine levels was observed at a dose of 10 mg/kg malathion. At 8 h, a maximal effect was observed at a dose of 700 mg/kg and the response was more prolonged than at lower doses. At 12 and 24 h after administration, the level of histamine in the serum of treated mice was comparable to controls. A similar pattern was observed in rats. However, the time point at which histamine levels returned to control was 8 rather than 12 h. After application of malathion to the skin of mice or rats in dimethyl sulphoxide (DMSO), the level of histamine in the blood was also increased. As before, the peak increase was observed at 4 h after administration and the level had returned to control levels within 8 h (slight increase at 8 h in rats) after application. However, after dermal application the maximal levels of histamine in the serum were noted at the highest doses of malathion. The no effect levels for histamine in the blood after malathion administration to these two species by these two routes are as follows: (1) Mice, oral in corn oil, 0.1 mg/kg; (2) Rats, oral in corn oil, 0.1 mg/kg; (3) Mice, dermal in DMSO, 2 mg/kg; (4) Rats, dermal in DMSO--not determined (2 mg/kg low effect level).

[Mutations and their significance in the corepromoter region of hepatitis B virus]

OBJECTIVE

To study the mutations in the core promoter (CP) region of hepatitis B virus (HBV) in Chinese viral hepatits B patients.

METHODS

CP regions of 48 HBV strains were analysed by polymerase chain reaction (PCR) direct sequencing approach.

RESULTS

67% of the samples were detected to have point mutations in the CP region. The hot spots located in nt 1754-1766 and nt 1801-1811 while nucleotides in nt 1777-1800 and nt 1812-1836 were highly conserved. nt. 1764 mutation was present in HBeAg negative patients. There were 16 point mutations in region overlapping X gene, 9 of which lead to amino acid change.

CONCLUSION

Though mutations in CP region of HBV appear frequently, the sequences associated with viral transcription are rarely changed. Point mutation at nt 1764 is related to HBeAg negative phenotype, but it is not the specific mutation of fulminant hepatitis. The importance of mutations in the X gene overlapping region needs to be further investigated.

Optical coatings for deuterium fluoride chemical laser systems

The high-power laser system has brought an interesting challenge to the development of optical coatings. A wide variety of coating specifications that are often contradictory have to be fulfilled. The choices of deposition process as well as coating materials are critical to coating loss, damage threshold, long-term stability, and other optical properties. A number of optical coatings being newly applied to deuterium fluoride laser systems are presented. The 3.8-mum laser reflection coatings with high damage threshold, multichromatic beam splitters, antireflection coatings with widely separated dual-wavelength bands, and 0.55-14-mum wide-band reflective coatings have been developed on substrates such as Si, Mo, fused silica, chemical vapor deposition ZnSe. Superior results have been obtained with ion-assisted deposition and electron-beam evaporation. Approaches to coating design and practical aspects of coating development are also discussed.

In vivo role of B lymphocytes in somatic transgene immunization

Immunity generated by in vivo inoculation of plasmid DNA is a straightforward and potentially valuable new approach to immunization. Little is known about the type of cells involved, the various immunological aspects, and the destiny of the transgene. In this report, we describe a system in which immunity is the result of in vivo targeting of B lymphocytes. This was accomplished using plasmid DNA encoding an immunoglobulin heavy-chain gene under the control of immunoglobulin promoter and enhancer elements. We show persistence of the transgene in splenic B lymphocytes for at least 3 months, i.e., the average life span of long-lived B lymphocytes in the mouse. The transgene could not be detected in any other lymphoid or nonlymphoid organs over a period of 6 months. We also established that the transgene is integrated in the host DNA. These studies bring new understanding to the events underlying the in vivo use of plasmid DNA. Moreover, the characteristics of this new approach make somatic transgene immunization a model system to study the immunogenicity of endogenous antigens in adult animals.

Effects of malathion metabolites on degranulation of and mediator release by human and rat basophilic cells

In the present study, the effects of malathion and malathion derivatives on histamine and beta-hexosaminidase release by RBL-1 cells, rat peritoneal mast cells (RPMC), and human peripheral blood basophils (HPBB) and cutaneous mast calls were examined. One hour of incubation of RBL-1 cells with all organophosphate compounds tested, except for malathion and malathion monoacid, led to an increase in histamine release. beta-Hexosaminidase, an enzyme released by basophilic cells and a biochemical marker of degranulation, was not released from RBL-1 cells after 1 h of exposure to organophosphate compounds. Within 4 h, all compounds tested increased the release of histamine and beta-hexosaminidase. Longer exposures led to a decrease in the concentration of the compound that was required to cause mediator release. Exposure of RPMC to organophosphate compounds, with the exception of malathion monoacid and malathion (30 min) or malathion monoacid (1 h), led to the release of histamine, but not beta-hexosaminidase. Incubation of HPBB with malaoxon (51.4 +/- 2.8% total histamine released), malathion diacid (25.7 +/- 2.9%), beta-malathion monoacid (31.4 +/- 2.8%), and isomalathion (57.1 +/- 17.1%) for 1 h led to the release of histamine. Only malaoxon and isomalathion caused beta-hexosaminidase release from HPBB after a 1-h incubation. Incubation of cutaneous mast cells with malaoxon and beta-monoacid for 4 h led to increased release of histamine and beta-hexosaminidase at levels comparable to compound 48/80. These data suggest that malathion metabolites can cause rapid release of histamine from basophilic cells from a variety of origins and species. With prolonged incubation, malathion itself caused the release of mast-cell mediators, suggesting that the cells may be capable of metabolizing malathion. These data also indicate a disparity between the release kinetics of two different mast-cell mediators contained in granules by organophosphates, and that there are different mechanisms of mediator release.

Effect of administration of malathion for 14 days on macrophage function and mast cell degranulation

Previous studies have shown that acute, oral administration of malathion modulated the humoral immune response to T-cell-dependent antigen, mitogenic responses, macrophage function, and mast cell degranulation. While administration of malathion for 14 days did not affect the generation of an immune response to antigen, it was possible that macrophage and mast cell functions were affected. In this report, the effect of malathion administration for 14 days upon these parameters were assessed. This treatment regimen increased the respiratory burst capacity to a maximal level at a dose of 1 mg/kg/day or greater. The effect of oral administration of malathion for 14 days on the degranulation of mast cells in various organs (heart, skin, and small intestine) and peritoneal lavage fluid was also assessed. At doses of 1 mg/kg/day and above, the number of mast cells that was undegranulated decreased and the number that was severely degranulated increased. There was no change in mast cell integrity in biopsies from heart and skin, and in peritoneal fluid after 14-day administration of 0.1 mg/kg/day. However, the number of mast cells associated with the small intestine that had undergone degranulation was increased at this dose of malathion. These data indicate that repeated administration of malathion increased macrophage function at doses as low as 1 mg/kg/day and led to mast cell degranulation at doses as low as 0.1 mg/kg/day.

Somatic transgene immunization with DNA encoding an immunoglobulin heavy chain

A plasmid DNA containing a chimeric immunoglobulin heavy-chain gene with tissue-specific promoter and enhancer elements was used as a model system to study the events triggered by a single intraspleen DNA inoculation in adult C57Bl/6 mice. A single intraspleen inoculation was followed in a week by secretion of transgene immunoglobulins and production of immunoglobulin M (IgM) anti-immunoglobulins. Their kinetics of serum appearance were almost superimposable. While anti-immunoglobulin antibodies remained detectable for over 6 months, transgene immunoglobulins disappeared after 3-4 weeks. However, transgene mRNA was detected in the spleen for 4 months. A multiplex polymerase chain reaction (PCR) analysis on splenic genomic DNA 17 days after inoculation demonstrated that the transgene was integrated in the host chromosomal DNA. The nucleotide sequence of the rearranged VDJ region from splenic genomic DNA was identical to that of the parental plasmid DNA, hence ruling out that hypermutation had occurred. A booster injection of immunoglobulin encoded by the transgene on day 200 elicited a typical secondary immune response with IgG1 and IgG2b antibodies. These results demonstrate that a single inoculation of an immunoglobulin heavy-chain DNA targeted to spleen lymphocytes leads to spontaneous integration of the transgene into the host DNA, and that this is sufficient to initiate immunity and establish immunologic memory. Our data also show that minute amounts (<100 ng/ml) of an endogenously produced protein secreted in the microenvironment of a lymphoid tissue generate immunity and establish immunologic memory rather than tolerance.

[Quantitative detection of serum hepatitis B wild type virus and the precore mutant genomes using competitive polymerase chain reaction in patients with HBeAg(-) chronic hepatitis B]

We set up a competitive PCR assay to obtain simultaneously a quantitative estimation of HBV wild type (M0) and precore mutant (M1 M2) genomes in sera of patients with HBeAg negative chronic hepatitis B and their evolution during antiviral therapy. The results showed that the amount of HBV DNA declined to undetectable levels very rapidly after the beginning of therapy in responders, while in non responders, the amount of viral genomes decreased but without becoming negative. Wild type viral strains (M0) seemed to be more sensitive to interferon as compared to precore mutant strains (M2). This method may be useful to study the course of viral infection and to evaluate the efficacy of antiviral therapy.

Contributions of inflammatory mast cell mediators to alterations in macrophage function after malathion administration

Recent studies using mast cell-defined mice showed that the presence of mast cells was necessary for the increase in macrophage function observed after oral administration of malathion and reconstitution with bone marrow-derived mast cells restored the ability of malathion to increase macrophage function. In addition, the release of mast cell mediators (blocked by cromolyn) and histamine (action blocked by pyrilamine) was shown to be involved in the action of malathion on macrophage function. In the present study, the contribution of inflammatory mediators (i.e. arachidonic acid metabolites and tumor necrosis factor [TNF]) which may be generated by mast cells after oral administration of malathion, was examined. Controls in this study included the effects of the agent to be examined on: (1) resident peritoneal macrophages; and (2) macrophages elicited with pristane, and agent shown previously to stimulate macrophage function in the absence of mast cells. Intraperitoneal administration of indomethacin, and inhibitor of cycloxygenase, or neutralizing antibody to TNF 30 h before and 4 h after oral malathion blocked the ability of malathion to increase macrophage function, as measured by the generation of respiratory burst activity and the production of cathepsin D. On the other hand, administration of these agents to mice injected intraperitoneally with pristane did not affect the observed increase in cathepsin D production. Respiratory burst function after elicitation with pristane was slightly decreased (indomethacin) or not affected (antibody to TNF). The effect of intraperitoneal administration of nordihydroguaiaretic acid (NDGA), and inhibitor of both cycloxygenase and lipoxygenase, was also examined. Intraperitoneal administration of NDGA partially blocked the effects of oral administration of malathion on peritoneal macrophage function, but did not affect the function of resident pristane-elicited peritoneal macrophages. These data suggest that inflammatory mediators (potentially released from mast cells upon stimulation) contribute to the elevation in macrophage function observed after oral malathion administration.

[Effects of arsenic trioxide on the subcellular localization of PML/PML-RARalpha protein in leukemic cells]

OBJECTIVE

In order to illustrate the possible roles of PML-RARalpha protein in arsenic trioxide (AsO3)-induced NB4 cell apoptosis.

METHODS

Effects of As2O3 on the subcellular localization of PML-RARalpha in NB4 cells were studied.

RESULTS

(1) Anti-PML serum staining was reduced and PML granules emerged in the perinuclear cytoplasm in a diffuse pattern in HL-60 cells under As2O3 treatment; (2) abnormal PML/PML-RARalpha granules were decreased; (3) NB4 cells accumulated anti-PML serum staining granules in the cytoplasms were increased and similar accumulation also found in apoptotic cells; and (4) pretreatment with all-trans retinoic acid (ATRA) for 24 or 48 hours did not alter the As2O3 effects.

CONCLUSION

As2O3-induced apoptosis was independent of the retinoic acid signal pathway, and it might be regulated by PML/PML-RARalpha and/or other related genes.

[Preliminary study on the arsenic trioxide-induced NB4 cell apoptosis and its molecular mechanisms]

OBJECTIVE

To illustrate the possible cellular and molecular mechanisms of arsenic trioxide (As2O3) in the treatment of acute promyelocytic leukemia (APL).

METHODS

APL cell line NB4 was used for in vitro studies. The effect of As2O3 on APL was studied by using flow cytometry, DNA electrophoresis, Narthern blotting and Western blotting.

RESULTS

As2O3 induced NB4 cell apoptosis, while not inhibiting the growth and survival of two other leukemic cell lines (HL-60 and U937). Furthermore, As2O3 effectively down-regulated the expression of bcl-2 gene without changing the mRNA levels of other apoptosis-associated genes (including p53, c-myc, bax and bcl-XL).

CONCLUSION

These might be one of the molecular mechanisms of As2O3 induced NB4 cell apoptosis.

[Quantitative histological study of adult condylar proliferation zone]

The thicknesses and cell numbers of 43 adult condylar proliferation zone were observed by serial section and multiarea measurement in order to investigate the relationships between them and age. The samples were divided into three groups by age (19-45, 46-59, 60-74). By way of statistical analysis, the cell numbers and thicknesses of different areas of the same age group, different age of the same area, and the relationship between thicknesses and age was analysed. The results show that the average proliferation zone thickness is different among different age groups, it becomes thinner with the increase of age, and the cell number is decreased. There is high significant difference among different age groups (P < 0.01). But there is no significant difference of the proliferation zone thickness between the group of 45-59 years old and the older group (60-74)(P > 0.05). There is diverse correlation between thicknesses and age increase.

Analysis of hepatitis B virus genotypes and pre-core region variability during interferon treatment of HBe antigen negative chronic hepatitis B

The clinical importance of hepatitis B virus (HBV) genome variability has been reported recently. One example is the occurrence of hepatitis B virus pre-core mutants, which arise during spontaneous or interferon-induced seroconversion from HBeAg to anti-HBe and are thought to be selected by immune pressure. A survey of HBV pre-core mutants and viral genotypes in 35 HBeAg negative patients during interferon therapy was carried out to understand viral pathogenesis in this form of chronic hepatitis B. Seventeen patients responded to interferon therapy as assessed by the sustained normalization of serum ALT levels and the significant decrease of viremia levels. The response rate to interferon was independent of both initial serum viral DNA level and interferon doses. During interferon therapy, a significant decrease of M0 (wild-type pre-core sequence at pos. 1887-1908), M1 (TGG to TAG at pos. 1896) or M2 (TGG to TAG at pos. 1896, and GGC to GAC at pos. 1899) positive viral genomes was found in 48%, 42%, and 33% of patients, respectively. A higher response rate to interferon therapy was observed in patients infected with HBV genotype A (70%) or M0 positive strains (75%) as compared to patients infected with genotype D/E (40%) or M1/M2 positive strains (44%). The data support the hypothesis that pre-core defective HBV represent viral mutants with an increased capacity to resist exogenous alpha interferon. These findings emphasize that characterization of HBV genome variability prior to interferon therapy may help to predict antiviral response in HBeAg negative patients.

Analysis of hepatitis B virus genotypes and pre-core region variability during interferon treatment of HBe antigen negative chronic hepatitis B

The clinical importance of hepatitis B virus (HBV) genome variability has been reported recently. One example is the occurrence of hepatitis B virus pre-core mutants, which arise during spontaneous or interferon-induced seroconversion from HBeAg to anti-HBe and are thought to be selected by immune pressure. A survey of HBV pre-core mutants and viral genotypes in 35 HBeAg negative patients during interferon therapy was carried out to understand viral pathogenesis in this form of chronic hepatitis B. Seventeen patients responded to interferon therapy as assessed by the sustained normalization of serum ALT levels and the significant decrease of viremia levels. The response rate to interferon was independent of both initial serum viral DNA level and interferon doses. During interferon therapy, a significant decrease of M0 (wild-type pre-core sequence at pos. 1887-1908), M1 (TGG to TAG at pos. 1896) or M2 (TGG to TAG at pos. 1896, and GGC to GAC at pos. 1899) positive viral genomes was found in 48%, 42%, and 33% of patients, respectively. A higher response rate to interferon therapy was observed in patients infected with HBV genotype A (70%) or M0 positive strains (75%) as compared to patients infected with genotype D/E (40%) or M1/M2 positive strains (44%). The data support the hypothesis that pre-core defective HBV represent viral mutants with an increased capacity to resist exogenous alpha interferon. These findings emphasize that characterization of HBV genome variability prior to interferon therapy may help to predict antiviral response in HBeAg negative patients.

Contribution of mast cell mediators to alterations in macrophage function after malathion administration

Previous studies showed that acute administration of noncholinergic doses of malathion increased macrophage function and the generation of a primary humoral immune response to a T-dependent antigen and caused mast cell degranulation. Recent studies using mast cell-deficient mice showed that the presence of mast cells was necessary for the increase in macrophage function observed after oral administration of malathion, and reconstitution with bone marrow-derived mast cells restored the ability of malathion to increase macrophage function. In the present study, the contribution of mast cell mediators to alterations in macrophage function after oral administration of malathion was examined. Controls in this study included the effect of the agent to be examined on resident peritoneal macrophages and macrophages elicited with pristane, an agent that can stimulate macrophages in the absence of mast cells. Coadministration of intraperitoneal cromolyn, a stabilizer of mast cell membranes, with oral malathion blocked the ability of malathion to increase macrophage function as measured by the generation of respiratory burst activity, the phagocytosis of opsonized yeast, and the production of cathepsin D. On the other hand, administration of cromolyn to mice whose macrophage function was stimulated with pristane did not affect the observed increases in macrophage function. As oral administration of malathion caused histamine release, the ability of a histamine receptor antagonist, pyrilamine, to alter the response of peritoneal macrophages to oral administration of malathion was also examined. Intraperitoneal administration of pyrilamine partially blocked the effects of oral administration of malathion on peritoneal macrophage function, but did not affect the function of resident or pristane-elicited peritoneal macrophages. These data suggest that mediators from mast cells contribute to the elevation in macrophage function observed after oral malathion administration.

[Simultaneous rhinoplasty and blepharoplasty]

Simultaneous rhinoplasty and blepharoplasty are the commonest facial cosmetic operation. The paper presents 73 cases who underwent this procedure with satisfactory results from Jan. 1989 to Nov. 1993. The authors described operation steps, e.g., making lacuna in the dorsum, lengthening nasal columella, nasal tip plasty. It was emphasized that the pretarsal flap should contain complete network of the superficial fascia, and the soft tissue underneath be trimmed. All the dissection should be kept in the same cleavage, which would reduce intraoperative bleeding and postoperative edema.

Effects of malathion on humoral immunity and macrophage function in mast cell-deficient mice

Malathion, when administered at noncholinergic doses, was previously shown to enhance the humoral immune response to a T-dependent antigen, sheep red blood cells (SRBC), and macrophage function. In addition, malathion was shown to cause mast cell degranulation. The hypothesis that mast cells contribute to the observed alterations in humoral immunity and macrophage function was determined by examination of the effects of acute administration of malathion to mast cell-deficient mice on macrophage function and the generation of a humoral immune response to SRBC. Initial studies in two strains of mast cell-deficient mice (6-7 weeks old) indicated that oral administration of malathion reduced macrophage function in these mice, but enhanced macrophage function in the wild-type strain. Because both strains reacted in a similar fashion and the defect in the WBB6F1-W/WV strain allowed reconstitution, further studies were conducted with this strain. Exposure of either wild-type mice or mast cell-deficient mice with reconstituted with bone marrow-derived mast cells (BMMC) from the wild-type mice to malathion enhanced macrophage function and the production of circulating IgM, but not IgG, antibodies to SRBC on Days 3 and 5 after immunization. In contrast, administration of malathion to older mast cell-deficient mice suppressed the generation of IgM and IgG antibodies to SRBC on Days 3 and 5 after immunization, but did not affect macrophage function. In summary, the results presented indicate that the presence of mast cells was necessary for the increases in macrophage function and humoral immunity observed after acute oral administration of malathion to mice.

[Autocrine transforming growth factor-beta stimulates human ovarian cancer cell growth in vitro and in vivo]

OBJECTIVES

Our previous studies have shown that human ovarian cancer cell lines COC1 and COC2 secrete transforming growth factor-beta (TGF-beta) like substance in serum-free culture. In this study the effect of COC1 and COC2-produced TGF-beta like substance on COC1 and COC2 cell growth was investigated.

METHODS

The COC1 and COC2 RPMI 1640 serum-free conditioned media SFCM (SFCM1 from COC1, SFCM2 from COC2) were prepared, and their activities were investigated on COC1 and COC2 cell growth (SFCM1 on COC1, SFCM2 on COC2) in vitro and in vivo, and compared with that of TGF-beta.

RESULTS

SFCM1 and SFCM2 could separately promote COC1 and COC2 cell proliferation in culture with dose-dependent response, SFCM2 significantly promoted COC2 cell growth in BABL/C nude mice. Radioreceptor assay showed that both COC1 and COC2 expressed TGF-beta receptor (or binding site). The above mentioned SFCM growth-stimulating effects can be partially blocked by anti-TGF-beta antibody.

CONCLUSION

The results suggest that there may be TGF-beta autocrine loop in the two ovarian cancer cell lines, which is associated with autonomous proliferation of COC1 and COC2 cells.

Analysis of hepatitis B virus genotypes and pre-core region variability during interferon treatment of HBe antigen negative chronic hepatitis B

The clinical importance of hepatitis B virus (HBV) genome variability has been reported recently. One example is the occurrence of hepatitis B virus pre-core mutants, which arise during spontaneous or interferon-induced seroconversion from HBeAg to anti-HBe and are thought to be selected by immune pressure. A survey of HBV pre-core mutants and viral genotypes in 35 HBeAg negative patients during interferon therapy was carried out to understand viral pathogenesis in this form of chronic hepatitis B. Seventeen patients responded to interferon therapy as assessed by the sustained normalization of serum ALT levels and the significant decrease of viremia levels. The response rate to interferon was independent of both initial serum viral DNA level and interferon doses. During interferon therapy, a significant decrease of M0 (wild-type pre-core sequence at pos. 1887-1908), M1 (TGG to TAG at pos. 1896) or M2 (TGG to TAG at pos. 1896, and GGC to GAC at pos. 1899) positive viral genomes was found in 48%, 42%, and 33% of patients, respectively. A higher response rate to interferon therapy was observed in patients infected with HBV genotype A (70%) or M0 positive strains (75%) as compared to patients infected with genotype D/E (40%) or M1/M2 positive strains (44%). The data support the hypothesis that pre-core defective HBV represent viral mutants with an increased capacity to resist exogenous alpha interferon. These findings emphasize that characterization of HBV genome variability prior to interferon therapy may help to predict antiviral response in HBeAg negative patients.

[Effect of ovarian cancer produced-transforming growth factor-beta on phytohemagglutinin and interleukin-2-inducing proliferation of peripheral blood mononuclear cells]

OBJECTIVES

Our previous observation has demonstrated that human ovarian cell lines COC1 and COC2 are able to secrete transforming growth factor-beta (TGF-beta) in serum-free culture. The effect of ovarian cancer produced-TGF-beta was observed on phytohemagglutinin and interleukin-2-inducing proliferation of peripheral blood mononuclear cells.

METHODS

The effects of COC1 and COC2 from patients' ascitic fluid (AS1, AS2), the serum-free conditioned medium (SFCM1, SFCM2), and COC1- and COC2- bearing nude mice sera (NS1, NS2) on phytohemagglutinin (PHA) and interleukin-2 (IL-2)-inducing peripheral blood mononuclear cell (PBMC) proliferation and their correlation with TGF-beta were observed and compared.

RESULTS

It was shown that AS, SFCM and NS possessed inhibitory effects on PBMC proliferation. But in very low concentrations, PHA-induced by SFCM2 and IL-2-induced by SFCM1 as well as by NS1 and NS2 exerted promotive effects on PBMC proliferation. The above-mentioned SFCM effects similar to that of TGF-beta, might be partially blocked by anti-TGF-beta antibody.

CONCLUSIONS

The present results suggest that ovarian cancer cells may inhibit the host anti-tumor immunity through secreting TGF-beta, which may be associated with the highly malignant biological behavior of ovarian cancer and the threatening progressiveness of its clinical course.

ATP-sensitive binding of a 70-kDa cytosolic protein to the glucose transporter in rat adipocytes

We have identified a 70-kDa cytosolic protein (GTBP70) in rat adipocytes that binds to glutathione S-transferase fusion proteins corresponding to the cytoplasmic domains of the facilitative glucose transporter isoforms Glut1, Glut2, and Glut4. GTBP70 did not bind to irrelevant fusion proteins, indicating that the binding is specific to the glucose transporter. GTBP70 binding to the glucose transporter showed little isoform specificity but was significantly subdomain-specific; it bound to the C-terminal domain and the central loop, but not to the N-terminal domain of Glut4. The GTBP70 binding to Glut4 was not affected by the presence of 2 mM EDTA, 2.4 mM Ca2+, or 150 mM K+. The binding was inhibited by ATP in a dose-dependent manner, with 50% inhibition at 10 mM ATP. This inhibition was specific to ATP, as ADP and AMP-PCP (adenosine 5'-(beta, gamma-methylenetriphosphate)) were without effect. GTBP70 did not react with antibodies against phosphotyrosine, phosphothreonine, or phosphoserine, suggesting that it is not a phosphoprotein. The binding of GTBP70 to Glut4 was not affected by the pretreatment of adipocytes with insulin. When these experiments were repeated using rat hepatocyte cytosols, no ATP-sensitive 70-kDa protein binding to the glucose transporter fusion proteins was evident, suggesting that either GTBP70 expression or its function is cell-specific. These findings strongly suggest the possibility that GTBP70 may play a key role in glucose transporter regulation in insulin target cells such as adipocytes.

[Effects of interferon treatment on mutation of hepatitis B virus precore genome]

Effects of interferon (IFN) treatment on mutation of hepatitis B virus (HBV) precore were studied with a rapid polymerase chain reaction method to investigate the stop codon in the distal precore region during HBV precore mutation. 6 cases of chronic hepatitis B were treated with recombinant IFN alpha 1 3 x 10(6) U/day for 14 weeks. In 4 of them HBV DNA was undetectable after treatment. Precore mutant was detected in the remaining 2 cases whose HBV DNA was still positive. In a group of 11 cases not treated with IFN, mutants were detected in 3. HBV e antigen (HBeAg) became negative after IFN treatment in one case, the original wild strain was replaced by a status of co-existence of mutant and wild strain. These results suggest that HBeAg negative seroconversion after IFN treatment does not necessarily implicate a complete clearance of HBV and the possibility of mutation of precore still exists.

[A study on the relationship between morphology and gene heterogeneity in acute promyelocytic leukemia]

Aucte promyelocytic leukemia (APL) can be treated by all-trans retinoic acid (ATRA) with high complete remission rate. 50 cases of APL diagnosed morphologically were studied on their cytogenetics, molecular biology and response to treatment with ATRA. Forty-five cases showed chromosomal translocation t(15; 17) and PML/RAR alpha fusion gene (PML + RAR alpha + APL). They had typical morphologic change, in which hypergranular cells appeared more frequently in L type of PML/RAR alpha and microgranular cells in S type of PML/RAR alpha. Among the 45 PML + RAR alpha + APL patients 8 died early and 37 had complete remission with ATRA. In the remainging 5 patients, three had typical APL morphologic features in cytology, but one of them displayed t (11; 17) with PLZF+RARA alpha +, the second showed RAR alpha + PML - (PML - RAR alpha + APL) and the third PML - RAR alpha -(PML - RAR alpha - APL). They did not respond to ATRA treatment. These data indicate that APL is not a homogeneous disease. The other a patients had neither chromosomal translocation nor rearrangements of the two genes. On careful morphological reexamination, these two cases were not APL, but one of them responded well to ATRA. It is shown that morphology is the important diagnostic basis of APL, but in a few APL cases diagnosis should be made with the help of cytogenetics and molecular biology. Response of ATRA treatment may be of diagnostic value of APL, but is not a specific criterion.

Vaginal reconstruction with an island flap of the inferior epigastric vascular pedicle

This paper presents a new method of vaginal reconstruction. On the basis of anatomic study, we designed an island flap obtained from the upper abdomen to carry the deep inferior epigastric vasculature. At operation, the flap was transferred to the artificial cavity created between the urinary bladder and rectum for vaginal reconstruction. Eight patients received the operation. Complete survival of the flap occurred in seven patients, and one flap failed because of a twist in the flap vascular pedicle. During a follow-up of 6 months to 2 years, it was found that the reconstructed vaginal wall was not only soft but also elastic, and the patients were able to have a satisfying sexual life after marriage.

[Studies on laxative function of maren soft capsule]

The experimental results show that the Maren soft capsule can increase the amount and weight of the stool of normal mice and model mice with dry stool, promote the advanced percentage of charcoal powder in the small and large intestines of mice, enhance the movement of the smooth muscle of isolated ileum of guinea pigs under physiological conditions or low temperature, as well as strengthen the intestinal movement in rabbits.