[The study and primary application of multimedia teaching and learning system for diseases of temporomandibular joint]

A multimedia computer-assistant teaching and learning system for diseases of temporomandibular joint was reported in this paper. It was designed and implemented in Windows (Chinese) on PC 486. It was emphasized that interactive teaching and learning was an available, funny method and student was the focus of teaching and learning in this system. A satisfied result was obtained by utilizing of this multimedia teaching and learning system for primary application.

In vitro inhibition of proliferation of HL-60 cells by tetrandrine and coriolus versicolor peptide derived from Chinese medicinal herbs

Coriolus versicolor polysaccharide peptide (CVP) and the bis-benzylisoquinoline alkaloids, tetrandrine (TET) and berbamine (BER), the active ingredients isolated from Chinese medicinal herbs known to possess antitumor activities, concentration-dependently inhibited the proliferation of human leukemic HL-60 cells. CVP did not affect the growth of normal human peripheral blood lymphocytes (PBL), whereas TET elicited concentration-dependent cytotoxic effects. Morphological observation and DNA analysis revealed that CVP elicited no effect on the morphological features of HL-60 cells and did not cause DNA fragmentation, but TET and BER caused cell shrinkage with the formation of apoptotic bodies, and showed clear evidence of DNA fragmentation. These findings indicate that TET and BER, but not CVP, inhibited the proliferation of HL-60 cells via induction of apoptosis.

HLA-DRB1 alleles genotyping in patients with rheumatoid arthritis in Chinese

OBJECTIVE

To explore the role of HLA-DRB1 genes in the development of rheumatoid arthritis (RA) and the correlations between HLA-DR alleles and clinical manifestations of patients with RA.

METHODS

86 patients with rheumatoid arthritis and 106 race matched controls were studied in whom HLA-DR typing was performed by the method of DNA amplification with sequence-specific primers (PCR-SSP). The subtypes of HLA-DR4 were determined by the method of hybridization of PCR products with sequence-specific oligonucleotides (PCR-SSO). The absence or presence of HLA-DR4 and its subtypes was correlated with the clinical and serological characteristics of the patients.

RESULTS

Compared with controls, an increased gene frequency of HLA-DR4 (48.8% vs 17.9%, P < 0.001) and a decreased frequency of HLA-DR7 (16.3% vs 27.4%, P = 0.06) were found. The DRB1* 0405 account for 61.9% of DR4+RA patients and 21.1% of DR4+ controls (P < 0.01). There was no difference between the DR4+ and DR4- patients with respect to age, sex, duration of disease, rheumatoid factor (RF), extra-articular manifestations including secondary Sjogren's syndrome. According to the wrist X-ray stage, the patients of DR4+ were more severe than that of DR4- (P < 0.05).

CONCLUSION

HLA-DR4 and DR4 subtype of DRB1*0405 are related to the development of RA in Chinese. HLA-DR4 can be a useful prognostic marker in the patients with RA.

Widespread loss of gelsolin in breast cancers of humans, mice, and rats

Down-regulation of gelsolin, an actin-binding protein, is frequently found in several types of transformed cells and tumors. The present study demonstrates that gelsolin protein and RNA were absent or markedly reduced in human breast cancer cell lines relative to "normal" mortal human mammary epithelial cells and benign, immortalized cell lines. Moreover, actin filaments were usually attenuated coincident with the reduction in gelsolin. Gelsolin was also missing or greatly decreased in 70% of 30 human sporadic, invasive breast carcinomas examined by immunocytochemistry and in 100% of virally induced mouse and chemically induced rat mammary carcinomas evaluated by Northern analysis. Southern analysis revealed no major mutations in the gelsolin gene of human breast cancer cells. Our results show that partial or total loss of gelsolin expression is common to the majority of breast cancers of diverse etiologies in three animal species and point to gelsolin as a candidate suppressor of breast cancer.

Atrophy of the corpus callosum associated with cognitive impairment and widespread cortical hypometabolism in carotid artery occlusive disease

OBJECTIVE

To investigate whether atrophy of the corpus callosum is associated with cognitive impairment and widespread cerebral cortical hypometabolism in carotid artery occlusive disease.

PATIENTS

Twelve patients with unilateral internal carotid artery occlusive disease (1 with severe stenosis and 11 with occlusion) and no cortical infarction in the chronic stage (mean +/- SD age, 64 +/- 5 years).

MAIN OUTCOME MEASURES

Midsagittal corpus callosum area-skull area ratio (on T1-weighted magnetic resonance images), the sum of the scaled scores of the 6 subtests on the Wechsler Adult Intelligence Scale-Revised (Digit Span, Arithmetic, Picture Arrangement, Object Assembly, Block Design, and Digit Symbol), and cerebral metabolic rate of oxygen (measured with position emission tomography by using the oxygen 15 steady-state technique).

RESULTS

The degree of cognitive impairment varied but was strongly correlated with the severity of callosal atrophy (r = 0.92, P < .001). Patients with callosal atrophy and cognitive decline also showed decreased oxygen consumption in the bilateral cerebral cortices. Stepwise regression analysis revealed that the severity of white matter lesions, especially in the centrum semiovale, and that of cortical atrophy in the hemisphere with arterial disease were 2 important factors for callosal atrophy.

CONCLUSIONS

Callosal atrophy is associated with cognitive impairment and widespread cerebral cortical hypometabolism in carotid artery occlusive disease without cortical infarction. Callosal atrophy might reflect the severity of the disconnection between cortical regions, and this may be an important factor in the development of cognitive impairment with widespread cortical hypometabolism in carotid artery occlusive disease without large cortical lesions.

p53 mutations in transitional cell carcinomas of the urinary bladder in rats treated with N-butyl-N-(4-hydroxybutyl)-nitrosamine

Involvement of p53 gene alterations has been demonstrated in a variety of human neoplasias including urinary bladder carcinomas. N-Butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced urinary bladder carcinogenesis models in rodents have been widely used to study carcinogenic processes in this organ. In the present study, transitional cell carcinomas induced in the urinary bladders of male F344 rats treated with 0.05% BBN for 16 or 32 weeks and then sacrificed at experimental week 32 were analyzed for mutational changes in the p53 and H-ras genes by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and subsequent DNA sequencing. The total p53 mutation incidences were 3/10 (30%) and 8/12 (66.7%) in rats treated with BBN for 16 weeks followed by 16 weeks' non-treatment, or in rats treated with BBN for 32 weeks, respectively, while the H-ras mutation incidences were 0/10 (0%), and 1/12 (8.3%), respectively. The present results indicate that mutations in the p53 gene might be involved in the process of urinary bladder carcinogenesis by BBN as part of a multistep pathway. However, considering the decreasing tendency in lesions with p53 mutations after stopping BBN administration, a p53 mutation alone would not appear to be sufficient to give a marked selective advantage to mutant cells. No evidence of H-ras mutation involvement was gained even for the late course of rat urinary bladder carcinogenesis.

[Immunohistochemical study of lactate dehydrogenase isoenzymes in gastric cancer: light and electron microscopic observations]

In order to study the metabolic features of gastric cancer, the relationship between intestinal metaplasia or dysplasia and gastric cancer, and the relationship between LDH isoenzymes and biological behavior of gastric cancer, the content and distribution of lactate dehydrogenase (LDH) isoenzymes in 60 cases of gastric cancer were observed with immunohistochemical and immunoelectron microscopic techniques. The results showed that the content of LDH5 in gastric cancer cells was higher than that in any cells of normal gastric epithelium except parietal cells (P < 0.001). LDH-H (LDH1-LDH4) in cancer cells was lower than in parietal cells, but was not significantly different from that in chief cells and surface epithelium. Under electron microscope, LDH5 in cancer cells was mainly distributed in the matrix of cytoplasm, while LDH-H was scarce. LDH5 in the epithelium of intestinal metaplasia (IM) or dysplasia was higher than in pyloric glandular epithelium (P < 0.05), but was not significantly different from that in cancer cells (P > 0.2). LDH-H in the epithelium of IM or dysplasia was higher than that in pyloric glandular epithelium and gastric cancer cells (P < 0.05). The results suggest that increased LDH in gastric cancer cells is resulted mainly from increased LDH5, which makes the gastric cancer cells produce more lactate, with decrease in local pH. Invasion and spread of cancer cells could be indirectly promoted through an elevated activity of acid hydrolases. IM and dysplasia may be considered as borderline lesions from normal gastric mucosa to gastric cancer.

[Changes of chemical constituents of radix Sophorae flavescentis in complex formulas of traditional Chinese medicine]

Experiments have been made on the changes of chemical constituents in complex formulas of traditional Chinese medicine. The results show that in the complex formula containing Radix Sophorae Flavescentis, as affected by various conditions of processing such as water, temperature and coexisting reductive substances, the content of oxymatrine tends to decrease gradually to disappear while that of matrine increase gradually.

[Expression of cytokines in labial gland of Sjögren's syndrome]

OBJECTIVE

To explore the role of cytokines in the process of inflammation and destruction of minor salivary gland in Sjögren's Syndrome. (SS) METHODS: Using in situ non-isotope double hybridization method, we detected the mRNA of the following cytokines: TNF alpha, IL-1 beta, IL-6, PDGF alpha and PDGF beta in 24 labial gland biopsied sections.

RESULTS

No cytokine could be detected in the normal labial glands sections. The positivity of all cytokine expression was higher in the pSS and sSS patients than that in the control. The intensity of TNF alpha expression was 3-4 fold increase in pSS compared with sSS. The different cytokines were expressed with the different grade of lymphocytic focus. The site of different cytokines was also expressed differently. The coexpression of mRNA of TNF alpha and IL-1 beta or TNF alpha and IL-6 was only seen in the inflammatory mononuclear cells but not others. The expression of TNF alpha in aciniar cells could occur earlier than the infiltration of lymphocytes in the interstitial region. It was found that the IL-6 positive group had higher positivity of serum ANA compared with the IL-6 negative group according to Ridit statistical analysis (P < 0.05). The serum anti-SSA and anti-SSB antibody had an increase tendency in the IL-6 positive group.

CONCLUSION

We hypothesize that the development of SS may be secondary to some trigger agents, which activated the aciniar cells in exocrine gland of predisposed individuals. The activated acini cells secreted TNF alpha, then TNF alpha induced other cytokine expression, followed by the lymphocytes infiltration, which led to autoimmne reaction and the destruction of the exocrine gland.

Gene therapy for malignant gliomas using replication incompetent retroviral and adenoviral vectors encoding the cytochrome P450 2B1 gene together with cyclophosphamide

Cyclophosphamide is an inactive prodrug which is converted by hepatic cytochrome P450 2B1 to cytotoxic metabolites which produce interstrand DNA cross-linking in a cell cycle-independent fashion. The limited ability of these metabolites to cross the blood-brain barrier contributes to the poor activity of cyclophosphamide against brain tumors. In this study we demonstrate that replication deficient retroviral and adenoviral vector-mediated gene transfer of cytochrome P450 2B1 into 9L glioma cells significantly increases the sensitivity of these tumor cells to cyclophosphamide in vitro, and prolongs the survival of animals bearing intracerebral 9L tumors treated with cyclophosphamide in vivo. Attempts to improve the effectiveness of retrovirally mediated transduction of the P450 2B1 gene by increasing the concentration of cyclophosphamide delivered to the tumors using intracarotid and intratumoral injections did not prolong animal survival, although survival was increased when a second treatment with P450-expressing retroviral vectors and cyclophosphamide was administered. These results suggest that in situ transduction of tumor cells with the P450 2B1 gene using retroviral and adenoviral vectors increases their sensitivity to cyclophosphamide and may have a potential role in the therapy of malignant gliomas.

Antitumor effects of a refined polysaccharide peptide fraction isolated from Coriolus versicolor: in vitro and in vivo studies

RPSP, a refined polysaccharide peptide fraction isolated by fast performance liquid chromatography (FPLC) from the crude powder of total peptide-bound polysaccharides of cultivated Coriolus versicolor Cov-1 dose-dependently inhibited the proliferation of a human hepatoma cell line (HEPG2). The effective dose causing 50% inhibition following 3-day exposure to RPSP was 243 +/- 36 micrograms/ml for HEPG2. However, little or no inhibitory effects were detected in normal human foetal hepatocytes. On the other hand, in the pretreatment group, in which RPSP was administered i.p. for two weeks before sarcoma 180 inoculation in nude mice, the incidence of tumor growth was less (2 out of 5 mice) than that of the control group (all 5 mice). The tumor size of the control group was about 3-5 times bigger than that of the pretreatment group. In tumor-bearing nude mice, 5 days after sarcoma 180 inoculation, i.v. administration of RPSP significantly suppressed the growth of tumor mass. The inhibition rate was 93.6% on day 13. Furthermore, administration of RPSP did not cause any pathological lesions in vital organs of rabbits such as heart, liver, spleen, lung and kidney. In conclusion, these results indicate that RPSP acts by directly suppressing tumor cell growth in vitro and the prevention of in vivo growth of tumor mass is probably mediated also via its immunomodulating effects.

Viral vector transduction of the human deoxycytidine kinase cDNA sensitizes glioma cells to the cytotoxic effects of cytosine arabinoside in vitro and in vivo

Cytosine arabinoside (ara-C) is a cytidine analog that incorporates into replicating DNA and induces lethal DNA strand breaks. Although ara-C is a potent antitumor agent for hematologic malignancies, it has only minimal activity against most solid tumors. The rate-limiting step in intracellular ara-C activation is phosphorylation of the prodrug by deoxycytidine kinase (dCK). The present results demonstrate that both retroviral and adenoviral vector-mediated transduction of the dCK cDNA results in marked sensitization of glioma cells lines to the cytotoxic effects of ara-C in vitro. We also demonstrate that ara-C treatment of established intradermal and intracerebral gliomas transduced with dCK results in significant antitumor effects in vivo. These data suggest that viral vector transduction of the dCK gene followed by treatment with ara-C represents a new chemosensitization strategy for cancer gene therapy.

In vivo replication-deficient adenovirus vector-mediated transduction of the cytosine deaminase gene sensitizes glioma cells to 5-fluorocytosine

Viral vector-mediated transfer of chemosensitization genes represents a promising new approach to the treatment of cancer. Previous reports have demonstrated that transfection of the bacterial cytosine deaminase (cd) gene into mammalian cells can sensitize them to the otherwise nontoxic nucleoside, 5-fluorocytosine (5-FC). We now report that a replication-deficient adenovirus vector that transduces the cd gene (Ad.CMV-cd) highly sensitizes 9L gliosarcoma cells to 5-FC, and that gene transduction is associated with a potent bystander effect that is not dependent on direct cell-to-cell contact. Stereotactic injection of Ad.CMV-cd into established rat gliomas, followed by systemic administration of 5-FC in vivo, results in prolongation of survival.

[Preliminary diagnostic criteria for primary Sjogren's syndrome in China]

Primary Sjogren's syndrome (pSS) is a common autoimmune connective tissue disease in China yet without a universally accepted diagnostic criteria. In this study a new criteria was proposed and compared with other six sets of criteria. Fifty-five items in 112 pSS and 185 controls were evaluated. Results show the criteria we proposed contained one major and nine minor items. For the purpose of identifying patients in clinical studies, a major with at least three of the nine minor items or at least five of the minor items should be presented. The major item is anti-SSA/SSB(+) and the minors are, (1) dry eyes or dry mouth (> 3 months, persistently), (2) swollen salivary glands (recurrently or persistently), (3) rampant dental caries, (4) Schirmer test (< 5 mm in 5 min.) or corneal staining(+), (5) unstimulated salivary flow (< 0.03 ml/min) or abornal parotid sialography, (6) minor salivary gland biopsy (> or = 1 focus), (7) renal tubular acidosis, (8) hypergammaglobuminemia (gamma globulin > or = 30%) or hypergammaglobuminemic purpura, (9) RF > 1 : 20 or ANA > 1 : 20. Other connective tissure diseases, pre-existing lymphoma, AIDS, sarcoidosis, graft vs host disease must be excluded. The criteria we proposed had a high specificity of 98.2% and sensitivity of 94.1%.

[CuZn-SOD determination of sera in patients with rheumatic diseases]

Superoxide anion (O2.-) plays an important part in reactive oxygen species (ROS). In order to explore its effect on the pathogenesis of rheumatic diseases, authors had determined CuZn-SOD contents of sera in 132 subjects involving the patients of rheumatic diseases (SLE, RA, etc), non-rheumatic diseases and normal controls by using enzyme linked immunosorbent assay (ELISA). The results showed the followings: CuZn-SOD contents of 27 normal subjects: 98.80 +/- 20.74 ng/ml (x +/- s); that of 27 non-rheumatic diseases cases: 72.24 +/- 16.60 ng/ml (x +/- s); of 22 SLE cases: 56.56 +/- 19.27 ng/ml (x +/- s); of 27 RA cases: 61.56 +/- 20.53 ng/ml (x +/- s); of 29 other rheumatic diseases cases: 68.97 +/- 17.79 ng/ml (x +/- s). Statistical test was made: both CuZn-SOD contents of rheumatic disease and non-rheumatic disease were lower than that of normal subjects with more significant difference (P < 0.001); compared with that of non-rheumatic diseases patients, SLE cases had significant difference (P < 0.01); RA cases had significant difference (P < 0.05); other cases of rheumatic diseases had no statistical differrence (P > 0.05). Above results suggest that superoxide anion is a non-specific inflammatory mediator which contributes to disorders with inflammatory damages (rheumatic or non-rheumatic diseases), where CuZn-SOD content tested was obviously lower than normal subjects; among the rheumatic disease patients, CuZn-SOD contents of the sera of SLE patients were the lowest because of its more autoimmune antibody, more severe inflammatory and immunological reaction. This work laid the theoretical and experimental foundation for the clinical application of exogenous CuZn-SOD in the treatment of rheumatic diseases. Combined use of CuZn-SOD scavengers may get better result because of the complexibility of ROS inflammatory mechanism.

[Ribozyme targeted the point-mutation of activated oncogene inhibits its expression in vivo]

We demonstrated previously that the hammerhead ribozyme designed by us against the activated oncogene T24-ras cleaved the target mRNA specifically and efficiently in vitro. To study its properties in vivo, we cloned the DNA fragment encoding the ribozyme into the eukaryotic expression vector pSMG and transfected it into the T24-ras gene transformed NIH3T3 cell lines. The intracellular cleavage of T24-ras mRNA was evaluated on either the cytological level or the molecular level. The malignant cells expressing ribozyme were partially reversed in morphology as evidenced by slower growth speed, partial recovery of contact-inhibition, reduced frequency of colony forming in soft agar and close-to-normal behaviour in agglutination teat. The primer extension experiment verified that the ribozyme had efficiently cleaved the transcripts of T24-ras gene at the target site in vivo.

[Expression of p53 in human esophageal carcinoma and pre-malignant lesions in the esophagus]

The levels of p53 protein were detected by immunocytochemistry in 197 endoscopic biopsy specimens of esophagus. Nuclear p53 protein was present in 2.9% of normal mucosa, 6.7% of inflammatory mucosa, 38.8% of mild dysplasia, 52.0% of moderate or severe dysplasia, 61.1% of carcinomas in situ, 62.5% of invasive carcinomas. Moreover, we examined 14 cases of esophageal carcinoma with extensive dysplasia near the carcinoma and found high levels of p53 protein in both dysplasias and carcinomas in 8 cases. In one case, carcinoma presented high level of p53 protein while the adjacent dysplasia did not. In another case, the result was just the opposite. Negativity for p53 immunostaining was found in 4 cases. These data indicated that p53 protein accumulation occurred before tumor invasion in the multistage esophageal carcinogenesis. The timing and the frequency of p53 protein accumulation made p53 gene an attractive marker for the early diagnosis an the evaluation of chemopreventive agents.

Breast cancer selective gene expression and therapy mediated by recombinant adenoviruses containing the DF3/MUC1 promoter

The high molecular weight mucin-like glycoprotein, DF3 (MUC1), is overexpressed in the majority of human breast cancers. Here we demonstrate that replication defective recombinant adenoviral vectors, containing the DF3 promoter (bp -725 to +31), can be used to express beta-galactosidase (Ad.DF3-betagal) and the herpes simplex virus thymidine kinase (HSV-tk) gene (Ad.Df3-tk) in DF3 positive breast carcinoma cell lines. In vivo experiments using breast tumor implants in nude mice injected with Ad.DF3-betagal demonstrated that expression of the beta-galactosidase gene is limited to DF3-positive breast cancer xenografts. Moreover, in an intraperitoneal breast cancer metastases model, we show that i.p. injection of Ad.DF3-tk followed by GCV treatment results in inhibition of tumor growth. These results demonstrate that utilization of the DF3 promoter in an adenoviral vector can confer selective expression of heterologous genes in breast cancer cells in vitro and in vivo.

Ins(1,4,5)P3 activates Drosophila cation channel Trpl in recombinant baculovirus-infected Sf9 insect cells

The trp-like (trpl) gene product (Trpl) is thought to form a nonselective cation channel important for signal transduction in Drosophila photoreceptor cells. This channel may be the insect homologue of mammalian channels involved in Ca2+ signal transduction. To determine the mechanism of receptor-mediated activation of Trpl, whole cell membrane currents were examined in Sf9 insect cells after infection with recombinant baculovirus. Stimulation by bradykinin increased whole cell Trpl currents three- to fivefold. Similar activation of Trpl was observed by inclusion of D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] in the pipette solution during whole cell recordings. These currents were 1) not seen in noninfected cells or in cells expressing only the B2 receptor, 2) mimicked by D-myo-inositol 2,4,5-trisphosphate, and 3-deoxy-3-fluoro-D-myo-inositol 1,4,5-trisphosphate, 3) not seen with D-myo-inositol 1,4-bisphosphate or D-myo-inositol 1,3,4,5-tetrakisphosphate, and 4) blocked by heparin, but not by de-N-sulfated heparin. In contrast, Trpl currents were unaffected by thapsigargin. These results demonstrate that the Trpl cation channel is activated by Ins(1,4,5)P3 in a heparin-sensitive fashion. Regulation of channel activity by Ins(1,4,5)P3 may occur by a number of mechanisms, including direct binding of Ins(1,4,5)P3 to the Trpl channel or direct physical interaction between the Ins(1,4,5)P3 receptor/Ca(2+)-release channel of the endoplasmic reticulum and the Trpl protein.

Ultrastructural cytochemistry of human gastric cancer: electron microscopic observations of five organellae marker enzymes

The distribution of ALPase, ACPase, G6Pase TPPase and CCOase of gastric cancer and normal gastric epithelium were studied ultrastructurally. The results showed that normal gastric epithelium had no ALPase reaction. The reactions of ACPase, G6Pase, TPPase and CCOase were found in the corresponding organellae which were consistent with their functions. In tubular adenocarcinoma cells, their reactions were more apparent in the corresponding organellae. Some cells of tubular adenocarcinomas showed ALPase reaction. The mucinous adenocarcinoma cells had higher ACPase and TPPase reactions. In poorly differentiated adenocarcinoma cells, the five marker enzymes showed negative or faint reactions. The biological significance and mechanisms of distribution of the five marker enzymes were discussed.

[Effect of sex steroids on serum amyloid P-component (female protein) in rats]

Serum amyloid P-component (SAP) has been designated as a female protein in hamsters. But such a distinction is not made for rats. In order to investigate the effects of sex-steroids on the SAP level in rats, SAP was purified from Wistar rats by affinity chromatography of phosphorylcholine, followed by gel filtration. Anti-SAP was raised through the immunization of rabbits with the rat SAP and Freund's adjuvant. Sample sera were obtained from 180 young and old rats, after which rats were injected with estradiol (E2), testosterone (T) or dehydroepiandrosterone (DHEA). Sera were serially obtained from the tail vessels until the 8th day after injection. The SAP level was assayed by micro single radial immunodiffusion. As the rats aged, the SAP levels increased from 2.9 mg/dl at 11 weeks to 10.7mg/dl at 58 weeks. In 37-week-old rats, the SAP levels in females (6.3 +/- 1.8 mg/dl) were significantly (p < 0.001) higher than those in males (3.9 +/- 1.0 mg/dl). The SAP levels did not change after T administration, but were increased rapidly by E2 administration, especially in young male rats (increased from 2.6 +/- 0.2 mg/dl to 4.9 +/- 0.7 mg/dl). The SAP levels were decreased significantly (p < 0.05) by DHEA injection. Serum E2 levels in young (11 wk) male rats were very low before E2 injection, and rose steeply on the 2nd day. From these findings, the different SAP levels in mature female and male rats are attributed to E2.