Carcinogenic potential of duodenal reflux juice from patients with long-standing postgastrectomy

AIM: To determine whether study on the carcinogenic potential of reflux juice from patients with remote gastrectomy could clarify the inherent relationship between duodenal reflux and gastric stump cancer.

METHODS: A total of 37 reflux juice samples (13 Billroth I, 24 Billroth II) were employed in the present study. A two-stage transformation assay using BALB/c 3T3 cells was carried out to test the initiating or promoting activity of these samples.

RESULTS: Two of 18 (11.1%) reflux samples exerted initiating activities, whereas 9/19 (47.4%) samples enhanced the MNNG-initiating cell transformation, suggesting the duodenal reflux juice might more frequently possess the tumor-promoter activity (P = 0.029). In addition, there was no difference in initiating activities of the samples irrespective of surgical procedures (P = 0.488), while Billroth II samples exhibited stronger tumor-promoter activity than Billroth I samples (P = 0.027). Furthermore, the promoter activities were well correlated with the histological changes of the stomas (r_s = 0.625, P = 0.004), but neither their cytotoxicities nor initiating activities had this correlation (Probabilities were 0.523 and 0.085, respectively).

CONCLUSION: The duodenal reflux juice from patients with remote postgastrectomy did have carcinogenic potential, and suggested that tumor-promoting activity should principally account for the high incidence of gastric cancer in gastrectomy patients. In contrast, it is difficult to explain the high stump-cancer incidence with the "N-nitroso compounds" theory-a popular theory for the intact stomach carcinogenesis, and it seemed to be justified to focus chemoprevention of this cancer on the tumor-promoting potential of reflux juice.

Regulation of differentiation- and proliferation-inducers on Lewis antigens, alpha-fucosyltransferase and metastatic potential in hepatocarcinoma cells

The expressions of Lewis (Le) antigens, alpha-1,3/1,4 fucosyltransferases (alpha-1,3/1,4 FuTs), and metastatic potential after the treatment of 2 differentiation inducers, all- trans retinoic acid (ATRA), 8-bromo-cyclic 3',5'adenosine monophosphate (8-Br-cAMP); and 2 proliferation inducers, epidermal growth factor (EGF) and phobol-12-myristate-13-acetate (PMA), on 7721 human hepatocarcinoma cell line were studied. Cell adhesion to human umbilical vein endothelial cells (HUVEC), cell migration through transwell and invasion through matrigel were selected as the indexes of metastatic potential-related phenotypes. Using fluorescence-labelled antibodies and flow-cytometric analysis, it was found that 7721 cells mainly expressed sialyl Lewis X (SLe(x)) and a less amount of sialyl dimeric Lewis X (SDLe(x)) antigens on the cell surface. Their expressions were down-regulated by ATRA, and up-regulated by EGF. SLe(x)antigen was also decreased and increased by the treatment of 8-Br-cAMP and PMA respectively. With Northern blot to detect the mRNAs of alpha-1,3/1,4 FuTs, the main enzymatic basis for the change in SLe(x)expression was found to be the alteration of the expression of alpha-1,3 FuT-VII. It was evidenced by the observations that alpha-1,3 FuT-VII was the main alpha-1,3/1,4 FuT in 7721 cells, while alpha-1,3/1,4 FuT-III and alpha-1,3 FuT-VI were expressed rather low. The changes in the expressions of SLe(x)antigen and alpha-1,3 FuT-VII resulted in the altered cell adhesion to tumour necrosis factor-alpha stimulated HUVEC, since only the monoclonal antibody of the SLe(x), but not other monoclonal antibodies blocked the adhesion of 7721 cells to HUVEC. The migration and invasion of 7721 cells were also reduced by the treatment of ATRA or 8-Br-cAMP, and elevated by EGF or PMA. The above findings indicate that the metastatic potential of 7721 cells is suppressed by differentiation-inducers and promoted by proliferation-inducers.

Transfection of the c-erbB2/neu gene upregulates the expression of sialyl Lewis X, alpha1,3-fucosyltransferase VII, and metastatic potential in a human hepatocarcinoma cell line

The pCMV4 plasmid containing the cancer-promoting gene, c-erbB2/neu, was cotransfected into the human hepatocarcinoma cell line 7721 with the pcDNA3 vector, which contains the 'neo' selectable marker. Several clones showing stable expression of c-erbB2/neu were established and characterized by determination of c-erbB2/neu mRNA and its encoded protein p185. Expression of Lewis antigens and alpha1,3-fucosyltransferases and the biological behavior of 7721 cells after c-erbB2/neu transfection were studied using mock cells transfected with the vectors pCMV4 and pcDNA3 as controls. SLe(x) expression on the surface of mock cells was high, whereas expression of SDLe(x), Lex and SLe(a) was absent or negligible. This is compatible with the abundant expression of alpha1,3-fucosyltransferase VII, very low expression of alphafucosyltransferase III/VI, and almost absent expression of alpha1,3-fucosyltransferase IV in the mock cells. After transfection of c-erbB2/neu, expression of SLe(x) and alpha1,3-fucosyltransferase VII were simultaneously elevated, but that of alphafucosyltransferase III/VI was not altered. The expression of both SLe(x) and alpha1,3-fucosyltransferase VII correlated positively with the expression of c-erbB2/neu in different clones, being highest in clone 13, medium in clone 6, and lowest in clone 7. In addition, the adhesion of 7721 cells to human umbilical vein endothelial cells (HUVECs) or P-selectin, as well as cell migration and invasion, were increased in c-erbB2/neu-transfected cells. These increases also correlated positively with the expression intensities of c-erbB2/neu, SLe(x) and alpha1,3-fucosyltransferase VII in the different clones, whereas cell adhesion to fibronectin correlated negatively with these variables. mAbs to SLe(x) (KM93) and SDLe(x) (FH6) significantly and slightly, respectively, abolished cell adhesion to HUVECs or P-selectin and cell migration and invasion. mAbs to SDLe(x) and SLe(a) did not suppress cell adhesion to HUVECs nor inhibit cell migration and invasion. Transfection of alpha1,3-fucosyltransferase VII cDNA into 7721 cells showed similar results to transfection of c-erbB2/neu, and the increased adhesion to HUVECs, cell migration, and invasion were also inhibited significantly by KM93 and slightly by FH6. These results indicate that expression of alpha1,3-fucosyltransferase VII and its specific product, SLe(x), and their capacity for cell adhesion, migration and invasion are closely related. Therefore, the c-erbB2/neu gene is proposed to be a metastasis-promoting gene, and its effects are at least partially mediated by the increased expression of alpha1,3-fucosyltransferase VII and SLe(x).

Dehydroepiandrosterone inhibits lipopolysaccharide-induced nitric oxide production in BV-2 microglia

Levels of dehydroepiandrosterone (DHEA) and its sulfated derivative (DHEAS) decline during aging and reach even lower levels in Alzheimer's disease (AD). DHEA is known to exhibit a variety of functional activities in the CNS, including an increase of memory and learning, neurotrophic and neuroprotective effects, and the reduction of risk of age-related neurodegenerative disorders. However, the influence of DHEA on the immune functions of glial cells is poorly understood. In this study, we investigated the effect of DHEA on activated glia. The production of inducible nitric oxide synthase (iNOS) was studied in lipopolysaccharide (LPS)-stimulated BV-2 microglia, as a model of glial activation. The results showed that DHEA but not DHEAS significantly inhibited the production of nitrite in the LPS-stimulated BV-2 cell cultures. Pretreatment of BV-2 cells with DHEA reduced the LPS-induced iNOS mRNA and protein levels in a dose-dependent manner. The LPS-induced iNOS activity in BV-2 cells was decreased by the exposure of 100 microM DHEA. Moreover, DHEA suppressed iNOS gene expression in LPS-stimulated BV-2 cells did not require de novo synthesis of new proteins or destabilize of iNOS mRNA. Since DHEA is biosynthesized by astrocytes and neurons, our findings suggest that it might have an important regulatory function on microglia.

Left paraduodenal hernia presenting as intestinal obstruction: report of one case

We report a case of internal hernia of the small intestine in a 13-year-old boy with presentation of partial intestinal obstruction. The patient suffered from recurrent abdominal pain and chronic constipation over the past few years. An abdominal mass was suspected from clinical manifestations and images derived from abdominal echography. Upper gastrointestinal contrast study revealed poor motility at the distal jejunum with barium stasis. Follow-up film on the next day delineated medially and downwardly displaced splenic flexure and proximal descending colon. At operation, total herniation of small intestine into a retroperitoneal space through a defect on left mesocolon was noted. A left paraduodenal (mesocolic) hernia was diagnosed. The patient made an uneventful recovery after the hernia was repaired. This report provides unusual image clues of internal hernias of the small intestine presenting as ileus. Though rare, paraduodenal hernia should be taken into account in a differential diagnosis of intestinal obstruction. Early surgical intervention allows uneventful recovery to occur and also prevents the possible complication of gangrenous bowels.

Relationship between metastasis-associated phenotypes and N-glycan structure of surface glycoproteins in human hepatocarcinoma cells

PURPOSE

To study the relation of N-glycan structure on cell surface glycoproteins to the metastatic phenotypes.

METHODS

Two human hepatocarcinoma 7721 cell lines transfected with sense or antisense cDNA of GnT-V, named GnT-V/7721 and GnT-V-AS/7721, respectively, were adopted, because GnT-V can change the antennary number and the content of the beta 1,6 GlcNAc branch in N-glycans. The effects of over- and under-expression of GnT-V on the metastasis-associated phenotype of the transfected cells were investigated and compared with the cells mock-transfected with the plasmid vector.

RESULTS

In GnT-V/7721 cells, GnT-V activity was increased by 92% compared with the mock cells. HRP-labeled lectin staining of transfected cells showed elevated intensity with HRP-L-PHA and reduced intensity with HRP-ConA, suggesting the increased antennary number and content of the beta 1,6 GlcNAc branch in N-glycans. Analysis of the N-glycan structure of [3H]-labeled glycopeptides prepared from cell-surface [3H] glycoproteins using DSA-affinity chromatography also revealed the above change of the N-glycan structure in a more quantitative manner. GnT-V/7721 cells showed a suppressed cell attachment to fibronectin (Fn) or laminin (Ln), and increased cell migration and invasion through matrigel. In contrast, GnT-V-AS/7721 cells showed reduction of both GnT-V activity and content of the beta 1,6 branch in N-linked glycans, elevation of cell attachment to Fn or Ln, and decline of cell migration and invasion through matrigel. These changes were just the opposite to those in GnT-V/7721 cells.

CONCLUSIONS

The alteration of N-glycan structure in surface glycoproteins resulting from the activity change of GnT-V contributes to the alterations in metastasis-associated phenotypes. The product of GnT-V, the beta 1,6 GlcNAc branch in N-linked glycans, is a structural factor of adhesion inhibition and invasion promotion. GnT-V is, therefore, closely related to cancer metastasis and its over-expression is an important molecular mechanism of metastasis.

An animal model for human EBV-associated hemophagocytic syndrome: herpesvirus papio frequently induces fatal lymphoproliferative disorders with hemophagocytic syndrome in rabbits

Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis. However, the animal model for EBV-AHS has not been developed. We reported the first animal model for EBV-AHS using rabbits infected with EBV-related herpesvirus of baboon (HVP). Eleven of 13 (85%) rabbits inoculated intravenously with HVP-producing cells developed fatal lymphoproliferative disorders (LPD) between 22 and 105 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in nine of these 11 rabbits. The peroral spray of cell-free HVP induced the virus infection with increased anti-EBV-viral capsid antigen-IgG titers in three of five rabbits, and two of these three infected rabbits died of LPD with HPS. Autopsy revealed hepatosplenomegaly and swollen lymph nodes. Atypical lymphoid T cells expressing EBV-encoded small RNA-1 infiltrated diffusely in many organs, frequently involving the lymph nodes, spleen, and liver. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by polymerase chain reaction or Southern blot analysis. Reverse transcriptase-polymerase chain reaction revealed both HVP-EBNA1 and HVP-EBNA2 transcripts, suggesting latency type III infection. These data indicate that the high rate of rabbit LPD with HPS induction is caused by HVP. This system is useful for studying the pathogenesis, prevention, and treatment of human EBV-AHS.

[Contents of ten trace elements in Epimedium acuminatum Franch. and its different processed products]

OBJECTIVE

Determine and compare the contents of ten trace elements in crude E. acuminatum and its three different processed products.

METHOD

Using flame atomic absorption spectrometry.

RESULT

The ten trace elements were found in both the crude drug and its three processed products, and in terms of contents some of the trace elements in all the three processed products are higher than those in the crude drug.

CONCLUSION

According to the trace element contents, the three processed products of E. acuminatum have their own advantages. It is thus suggested that thoroughgoing clinical and experimental researches be performed anew for the long-shelved processing methods.

Cerebellar metastasis from papillary serous adenocarcinoma of the ovary mimicking Ménière's disease. A case report

BACKGROUND

In rare cases, cerebellar metastasis originating in serous papillary adenocarcinoma of the ovary can mimick Ménière's disease.

CASE

A 51-year-old woman, with complete remission after optimal maximal debulking and chemotherapy for an International Federation of Gynecology and Obstetrics IIIc primary ovarian carcinoma, presented with nausea, vomiting, vertigo and headache 18 months after surgery. Investigations revealed a solitary cerebellar cystic mass, 4.6 x 4.0 x 3.2 cm. Gross total excision of the cerebellar lesion followed by brain irradiation resulted in complete resolution of her symptoms. Histology showed a metastatic tumor consistent with the primary ovarian carcinoma.

CONCLUSION

In an atypical presentation in patients with metastatic ovarian carcinoma, thorough investigations should be done to rule out or confirm brain metastasis, which can be aggressively managed to prevent serious consequences and improve outcome.

Effects of isomalto-oligosaccharides on bowel functions and indicators of nutritional status in constipated elderly men

OBJECTIVES

To evaluate effects of isomalto-oligosaccharides (IO) on the bowel function and nutritional status of elderly men.

METHODS

Seven older male subjects participated in this study that consisted of a 30-day control low fiber period followed by a 30-day IO-supplemented (10 g active components) experimental period. Bowel functions such as defecation, enema use and bloating were monitored daily. Fecal characteristics such as wet and dry stool weights, stool moisture, pH and short-chain fatty acid contents were determined on five-day fecal composites collected in each period. Feces were further fractionated into plant, bacterial and soluble fractions to determine the bases for the increase in stool weight. Nutritional status of subjects was assessed with anthropometric parameters, nutrient intake and biochemical measurements.

RESULTS

Incorporation of IO significantly increased the defecation frequency, wet stool output and dry stool weight by twofold, 70% and 55%, respectively. Fecal acetate and propionate concentrations significantly increased by nearly two and a half fold with IO supplement. The increase in stool bulk was mainly attributed by increased bacterial mass. Mean serum sodium concentration decreased in the experimental period while other blood characteristics did not change significantly. Anthropometric parameters and nutrient intake remained constant throughout the study.

CONCLUSIONS

Consumption of IO effectively improved bowel movement, stool output and microbial fermentation in the colon without any adverse effect observed in this study. Therefore, supplementation of IO into ordinary low fiber diets may be practical in relieving constipation in the elderly population.

Exposure assessment of indoor allergens, endotoxin, and airborne fungi for homes in southern Taiwan

This study was undertaken to examine the seasonal variations of domestic Der p 1, Der p 2, and endotoxin on mattress and airborne fungal concentrations in homes of asthmatic and nonasthmatic children in southern Taiwan, where temperature and relative humidity are usually high throughout the year. A group of asthmatic children (10-12 years old) were selected randomly based on a citywide questionnaire survey. The nonasthmatic children were chosen to be in the comparison group by matching in age, gender, and proximity of residence. Environmental sampling of domestic microbes was conducted once a month for a year. Twelve calendar months were grouped into spring, summer, fall, and winter according to weather data (mainly average temperature and humidity) from the Central Weather Bureau. Dust samples from a child's mattress and airborne samples from a child's bedroom were collected and analyzed for allergens of Der p 1 and Der p 2, endotoxin, and fungi respectively. Results show that about 65% of children's mattresses in our region have Der p 1 levels greater than 2 microg/g. It is also apparent that most airborne fungal concentrations found in homes of either asthmatic or nonasthmatic children are higher than the recommended levels of concern. The predominant genera are Cladosporium, Aspergillus, Penicillium, Alternaria, and yeast. In addition, seasonal effects seem to be a critical factor for the concentrations and distributions of domestic endotoxin in these study homes. The implication of long-term exposure to these high levels of environmental microbes and how their effects vary with seasons remain to be further characterized.

Inhibition of inducible nitric oxide synthase (iNOS) prevents lung neutrophil deposition and damage in burned rats

This study was designed to investigate the role of NO and effect of iNOS inhibitor on the lung neutrophil deposition and damage after burn. In Experiment 1, specific pathogen-free (SPF) Sprague-Dawley rats underwent 35% total body surface area (TBSA) burn. On the 4th, 8th, 16th, and 24th h after burn, blood was collected for peroxynitrite-mediated dihydrorhodamine 123 (DHR 123) oxidation assay, and lung tissues were harvested for myeloperoxidase (MPO) test and histologic study. Pulmonary microvascular dysfunction was quantitated by measuring the extravasation of Evans blue dye (EBD). In Experiment 2, S-methylisothiourea (SMT) was given (7.5 mg/kg, intraperitoneal immediately post-burn) to suppress iNOS activity. On the 8th h after burn, the effect of SMT on blood DHR 123 oxidation, lung MPO, lung damage, and lung iNOS expression were evaluated. Lung MPO activity increased up to a maximum of 2-fold 8 h after burn. Blood DHR 123 oxidation increased up to a maximum of 2-fold 8 h after burn. Lung permeability increased up to a maximum of 2.5-fold 4 h after burn. SMT significantly decreased lung MPO activity, blood DHR 123 oxidation, and lung permeability by 31%, 41%, and 54%, respectively. SMT markedly decreased the thermal injury-induced perivascular and interstitial inflammatory cell infiltration and iNOS staining in bronchiolar epithelium, endothelial cells, and perivascular and interstitial inflammatory cells. In conclusion, thermal injury induces blood DHR 123 oxidation, lung neutrophil deposition, lung iNOS expression, and lung damage. Peroxynitrite might play an important role in thermal injury-induced lung neutrophil deposition and damage. Specific inhibition of lung iNOS expression and blood DHR 123 oxidation with SMT on thermal injury not only attenuated the lung neutrophil deposition, but also reduced lung damage.

Association between obesity and hyperlipidemia among children

BACKGROUND

This study was undertaken to show the association between obesity and hyperlipidemia among the children.

METHODS

In March 2000, while conducting a comprehensive health examination, we analyzed 2011 children from the first grade of primary schools in Taichung City in Taiwan. To study the association between obesity and hyperlipidemia, the t test, chi-square analysis, and multivariate logistic regression were used.

RESULTS

There were 1057 boys (52.56 percent) and 954 girls (47.44 percent). The mean age was 7.27 +/- 0.46 years. The proportion of overweight was 11.07 percent in boys and 11.64 percent in girls. The proportion of obesity was 14.19 percent in boys and 12.89 percent in girls. After controlling the other covariates, the multivariate logistic regression analysis showed that overweight was associated with a low level of high density lipoprotein cholesterol. Obesity was associated with hypertriglyceridemia, a high level of low density lipoprotein cholesterol, and a low level of high density lipoprotein cholesterol.

CONCLUSIONS

Our findings disclosed that the prevalence of overweight and obesity was high in childhood. Early intervention to control and prevent childhood obesity might be warranted. Obesity was associated with hyperlipidemia in children. A wide-scale survey will be suggested in the future to establish causal-effect issues between obesiyy and hyperlipidemia.

Frequency doubling technology perimetry in retinal diseases--preliminary report

The role of frequency doubling technology perimetry (FDT) in glaucoma has been promising in speed and simplicity as well as in its high sensitivity and specificity compared to conventional automatic perimetry. In this study, we evaluate the role of frequency doubling technology perimetry (FDT) in a variety of retinal diseases. FDT using full-threshold C-20 mode was performed in thirty-three patients with a variety of retinal diseases [16 cases of rhegmatogenous retinal detachment (RRD), nine cases of age-related maculopathy (AMD) and eight cases of central serous chorioretinopathy (CSCR)]. The fundus was scored by the extent of disease on each quadrant and macular area (central five degree visual angle). Then the retinal scores were compared with the points depressed to 2% on total deviation plots in FDT C-20 full-threshold mode using Spearman's rank correlation method. The correlation was statistically significant in the group of RRD (R = 0.57, P = 0.01), whereas the correlation was not significant in the group of macular diseases (AMD & CSCR, R = 0.47 & 0.32, P = 0.12 & 0.20). In conclusion, our results suggest that FDT might be a useful and simple technique for functional evaluation in RRD, but not in the macular disease group under this scoring system.

[Expression of autoantibodies to ICA512 and GAD in the sera of patients with diabetic ketoacidosis or ketonemia]

To explore the expression of the autoantibodies to ICA512 and GAD65 in the sera of diabetic patients who will be diagnosed as Type 1 diabetes, autoantibody assays were carried out in 15 diabetic patients complicated with ketonemia or ketoacidosis and in 19 healthy controls. The results were that the positive ratios of these autoantibodies were higher in the patient's sera than in the control's, and were higher in patients with shorter disease duration than those with longer disease duration. It is suggested that detecting these autoantibodies is helpful to the classification of diabetes and the disease duration affects the antibody's positive ratio.

Hepatitis B vaccination and hepatocellular carcinoma rates in boys and girls

CONTEXT

Hepatocellular carcinoma (HCC) has a male predominance and is closely related to hepatitis B virus (HBV) infection. Hepatitis B virus vaccination was launched in 1984 in Taiwan for neonates of mothers carrying hepatitis B e antigen, resulting in a decreased incidence of HCC in children. The effect on boys vs girls is not known.

OBJECTIVE

To evaluate the association between a HBV vaccination program with incidence of childhood HCC by sex.

DESIGN AND SETTING

Analysis of data collected from Taiwan's National Cancer Registry System and the Taiwan Childhood Hepatoma Study Group between 1981 and 1996.

PARTICIPANTS

Children aged 6 to 14 years who were diagnosed as having HCC (201 boys and 70 girls).

MAIN OUTCOME MEASURE

Incidence of HCC in boys and girls before and after implementation of the vaccination program.

RESULTS

The boy-girl incidence ratio decreased steadily from 4.5 in 1981-1984 (before the program's introduction) to 1.9 in 1990-1996 (6-12 years after the vaccination program was launched). The incidence of HCC in boys born after 1984 was significantly reduced in comparison with those born before 1978 (relative risk [RR], 0.72; P =.002). No significant decrease in HCC incidence was observed in girls born in the same periods (RR, 0.77; P =.20). The incidence of HCC in boys remained stable with increasing age, while an increase of HCC incidence with age in girls was observed. These age and sex effects remained the same regardless of birth before or after the vaccination program.

CONCLUSION

Our results suggest that boys may benefit more from HBV vaccination than girls in the prevention of HCC.

Human peritoneal mesothelial cells produce nitric oxide: induction by cytokines

OBJECTIVE

To investigate the induction of nitric oxide synthase type II (iNOS) in human peritoneal mesothelial cells (HPMC) using cytokines and bacterial lipopolysaccharide (LPS).

DESIGN

Confluent monolayers of HPMC were exposed to cytokines [tumor necrosis factor alpha (TNFalpha), interleukin-1 beta (IL-1beta), interferon gamma (IFNgamma)] or LPS, individually or in various double and triple combinations, for 24-72 hours. Concentrations of nitrate and nitrite in the media were quantified using the Griess reaction and used as indirect indices of nitric oxide (NO) production. The expression of iNOS was assessed using reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot.

RESULTS

Neither single cytokines nor LPS was able to induce iNOS mRNA or NO production. Both double combinations of TNFalpha + IFNgamma and IL-1beta + IFNgamma were able to induce iNOS mRNA expression, but only TNFalpha + IFNgamma induced significant NO production. The triple combination of TNFalpha + IFNgamma + IL-1beta induced even more NO production than TNFalpha + IFNgamma. There was no constitutive NO synthase type III (eNOS) expression in HPMC.

CONCLUSIONS

Certain combinations of cytokines could stimulate cultured HPMC to produce NO, and HPMC might be a source of intraperitoneal NO production during peritonitis.

Right middle lobe atelectasis associated with endobronchial silicotic lesions

BACKGROUND

In a period of 18 months, we have encountered 4 cases of right middle lobe atelectasis associated with endobronchial silicotic lesions of right middle lobe bronchi. All patients had occupational exposure to mineral dusts (3 coal miners and 1 sand blaster) for months to decades.

METHODS

The nature of the endobronchial silicotic lesions that caused the bronchial obstruction has been confirmed by endobronchial biopsies and energy-dispersive spectrometry of the lesions. Extrinsic compression has been excluded by careful radiographic and computed tomographic image analysis.

RESULTS

The endobronchial silicosis does not appear to correlate with the degree of pneumoconiosis of the lung parenchyma. The endobronchial silicosis may cause bronchial obstruction in the absence of radiographic evidence of pulmonary silicosis.

CONCLUSION

The endobronchial silicosis and consequent lung atelectasis may be associated with silica exposure.

[Change of bone mineral density in type 2 diabetes mellitus with nephropathy]

OBJECTIVE

To investigate into the changes of bone mineral density(BMD) in Type 2 diabetes mellitus with nephropathy(DN) and without nephropathy(DM).

METHODS

BMD of lumbar vertebrae 1-4 and femur in 93 cases of Type 2 diabetes mellitus(41 cases of DN and 52 cases of DM) were measured with dual energy x-ray absorptiometry(DEXA) and were compared with age, sex, and BMI-matched normal control group.

RESULTS

No significant differences were found in BMD of femoral total, neck, L1-L4 between DM and normal controls in females(P > 0.05). DM in men had higher BDM at L2, femoral total neck than normal controls(P < 0.05). BMD at femoral total, neck, in females and L1-L4 femoral total neck in men in DN group were lower than DM group, but had no statistical differences.

CONCLUSION

The changes in BMD of above areas in DM were normal and higher because of different areas. BMD in DN had lower predisposition.

Immunogenicity and reactogenicity of the combined hepatitis A and B vaccine in young adults

The combination of hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccinations can offer convenience, increased compliance and cost saving. We have studied the immunogenicity, reactogenicity and safety of combined hepatitis A and B vaccination in young adults (16-35 years old). Eighty healthy young adults were divided into two random groups. One group received the combined hepatitis A and B vaccine (HAB) in one arm while the other group was administered concomitant hepatitis A and B vaccines (HAV + HBV) in the right and left arms, respectively. The immunogenicity, reactogenicity and safety were assessed after each dose in both the groups. In local symptoms, the percentage of the combined HAB group was lower than the HAV + HBV group, and the general symptoms were noted in approximately 30% of each group without any significant difference. No serious adverse effects were noted. All the subjects were seropositive for antibody to hepatitis A virus (anti-HAV) after one dose of vaccine, and remained seropositive after three doses in both groups. The seropositive rate for antibody to hepatitis B surface antigen (anti-HBs) was significantly higher (84%) in the combined HAB group than the concomitant HAV + HBV group (62%), (p<0.05) after dose two, and all the subjects were seropositive (100%) after the third dose. The GMTs of anti-HAV and anti-HBs were not significantly different between groups 1 and 2 (p>0.1) except in month 6 when the GMT of anti-HBs was higher in HAB group (p=0.0039). The combined HAB vaccine was found to be safe, well tolerated and had less local symptoms in young adults. The immunogenicity and reactogenicity were similar to the concomitant HAV + HBV vaccines.

Growth enhancement of fowls by dietary administration of recombinant yeast cultures containing enriched growth hormone

In present study the methylotrophic yeast, Pichia pastoris, was used to express a recombinant growth hormone (rGH) gene of swine. A synthetic secretion cassette was constructed using the promoter of the alcohol oxidase1 gene (AOX1), and a alpha-factor signal peptide. After electroporatic transformation and zeocin selection, several clones exhibited high levels of rGH protein expression constituting more than 20% of total yeast protein. Over 95% of rGH was shown to be export into the culture supernatant. Yeast transformant containing the highest recombinant growth hormone level (rGH yeast) and native GS115 Pichia pastoris (non-rGH yeast, as a control) were separately cultured, harvested and adsorbed by wheat bran. Yeast cultures of four dosages (0.05, 0.1, 0.2, and 0.4%) were mixed respectively with chick basal diet and fed to simulated country chickens for 9 weeks. The results showed that, when compared to control chicks, the percentage of body weight gain was improved significantly (P<0.05) in chicks fed with diets containing 0.1 or 0.2% rGH-rich yeast culture at brooding stage, and in chicks fed with 0.4% rGH-rich yeast culture at growing stage. The average weight gain in rGH yeast treated groups for the full-term (0 to 63d) and short term (43 to 63d) of growth were 10.6 and 9.4%, respectively, better than the non-rGH yeast control group. These experimental data suggest that the use of rGH-containing yeast as a supplement in fed provided an alternative approach for growth improvement in simulated country chickens.

Down-regulation of N-acetylglucosaminyltransferase V by tumorigenesis- or metastasis-suppressor gene and its relation to metastatic potential of human hepatocarcinoma cells

The effects of transfection of the metastasis suppressor gene nm23-H1 and cell-cycle related tumor-suppressor gene p16 on the activity of N-acetylglucosaminyltransferase V (GnT-V) and their relations to cancer metastatic potential were investigated. After transfection of nm23-H1 into 7721 human hepatocarcinoma cells and A549 human lung cancer cells, the activities of GnT-V were decreased by 28%-42% in the cells. In contrast, when p16 was transfected into these two cell lines, the decrease of GnT-V activity was only observed in A549 cells. This was probably to be due to the obvious expression of p16 gene in parental 7721 cells and the deletion of p16 in A549 cells. The decrease of GnT-V mRNA was only observed in nm23-H1-transfected cells, but not in p16-transfected A549 cells, suggesting that these two genes regulated GnT-V via different mechanisms. Horseradish peroxidase (HRP)-lectin staining showed that the 7721 cells transfected with nm23-H1 or the A549 cells transfected with p16 displayed a decreased intensity with HRP-leucoagglutinating phytohemagglutinin and increased intensity with HRP-concanavalin A, indicating the decline of beta1,6 N-acetylglucosamine branching structure on the asparagine-linked glycans of cell-surface and intracellular glycoproteins. The nm23-H1 transfected 7721 cells also displayed some changes in metastasis-related phenotypes, including the increase in cell adhesion to fibronectin (Fn), the decline in cell adhesion to laminin (Ln), and the decreased cell migration and invasion through matrigel. Transfection of antisense GnT-V cDNA into 7721 cells resulted in a decrease of GnT-V activity, an increase of cell adhesion to Fn or Ln, and a decrease in cell migration and invasion through matrigel. These phenotypes bore similarity to those of the 7721 cells transfected with nm23-H1. Our findings indicate that the down-regulation of GnT-V by nm23-H1 contributes to the alterations in metastasis-related phenotypes, and is an important molecular mechanism of metastasis suppression mediated by nm23-H1.

Hereditary fructose intolerance presenting as Reye's-like syndrome: report of one case

Hereditary fructose intolerance (HFI) is an autosomal recessive disease caused by catalytic deficiency of aldolase B (fructose-1, 6-bisphosphate aldolase). Herein we report on a case of hereditary fructose intolerance with initial presentation of episodic unconsciousness, seizure, hypoglycemia, hepatomegaly, and abnormal liver function since the patient was 11 months old. She was diagnosed as Reye's-like syndrome according to a liver biopsy done at 20 months of age. As she grew up, cold sweating, abdominal pain or gastrointestinal discomfort shortly after the intake of fruits was noted and she developed an aversion to fruits, vegetables and sweet-tasting foods. At 9 years of age, a fructose tolerance test signified a positive result that induced hypoglycemia, transient hypophosphatemia, hyperuricaemia, elevation of serum magnesium, and accumulation of lactic acid. Appropriate dietary management and precautions were recommended. The patient has been symptom-free and exhibited normal growth and development when followed up to 12 years of age.

Long-term follow-up study of core gene deletion mutants in children with chronic hepatitis B virus infection

Core gene deletion mutants of hepatitis B virus (HBV) have been identified in adults. Because the acquisition of HBV occurs mainly in infancy and childhood in hyperendemic areas, this study aimed to learn the temporal profile of such mutants in children with chronic HBV infection. We have followed up 365 HBV-infected children for more than 10 years and screened out HBV core gene deletion from their sera. Serial serum samples of positive cases were subjected to HBV-DNA nucleotide sequence analyses and quantification. Deletion mutants were found in 18 of the 365 patients (4.9%). Most cases (15 of 18) with deletion mutants heralded hepatitis B e antigen (HBeAg) seroconversion phase, while the other cases (3 of 18) remained in HBeAg-seropositive phase. Deletion mutants disappeared after HBeAg seroconversion except in 1 child. Decreased HBV-DNA levels accompanied deletion mutants for those who finally underwent HBeAg seroconversion, but the HBV-DNA level did not decline if there was no seroconversion. Deletion mutants were not associated with a particularly high peak liver enzyme. Core gene deletion mutants could appear as early as the age of 5. The duration of their appearance was 0.5 to 5 years. Horizontal rather than perinatal transmission of HBV was a favorable factor for these mutants to develop. Deletion fragments were located in the middle part of core gene. The emergence of the mutants was likely the result of host-viral interaction and mostly signified HBeAg seroconversion within 1 year. Core gene deletion mutants appeared preferably in children acquiring HBV by horizontal transmission.

Modulation of the basal activity of phosphatidylinositol-3-kinase/protein kinase B signaling pathway in human hepatocarcinoma cells

The modulation of GnT-V activity by signaling molecules in PI-3-K/PKB pathway in human hepatocarcinoma cell line 7721 was studied. GnT-V activity was determined after the transfection of sense or antisense cDNA of PKB into the cells, as well as the addition of activators, specific inhibitors, and the antibodies to the enzyme assay system or culture medium. It was found that the basal activity of GnT-V was up regulated by the sense and down regulated by the antisense cDNA of PKB transfected into 7721 cells. GnT-V was activated by PIP2, PIP3 or GTPgamma[S] added to the assay system, and the activation of PIP2 or GTPgamma[S] was abolished by LY2940002, a specific inhibitor of PI-3-K, but the activation of PIP3 was not attenuated by LY2940002. In addition, GnT-V activity in cultured parental or H-ras transfected cells was inhibited by the antibody against PKB or PI-3-K. These findings demonstrated the involvement of PI-3-K/PKB signaling pathway in the regulation of GnT-V. Moreover, ET18-OCH3, an inhibitor of Raf translocation and PI-PLC enzyme, which produces the activator of PKC, as well as the antibodies against Raf-1 or MEK also inhibited GnT-V activity in the parental and H-ras transfected cells. The inhibitory rates, however, were less in the transfected cells than those in the parental cells. These results reveal that in parental and H-ras transfected 7721 cells, the basal activity of GnT-V is also regulated by the Ras/Raf-1/MEK/MAPK cascade in addition to PI-3-K/PKB signaling pathway. The significance of these two pathways in the regulation of GnT-V and their relations to the activation of PKC previously reported by our laboratory (Ju TZ et al., 1995 Glyconjugate J 12, 767-772) was discussed.

Effects of H-ras and v-sis overexpression on N-acetylglucosaminyltransferase V and metastasis-related phenotypes in human hepatocarcinoma cells

Oncogenes and N-acetylglucosaminyltransferase (GnT-V) are both commonly associated with carcinogenesis and metastasis. In order to elucidate the relationship between oncogenes and GnT-V, two oncogenes, H-ras and v-sis/PDGF (platelet-derived growth factor), were selected, and the effects of their overexpression on GnT-V in 7721 human hepatocarcinoma cells were investigated. The results showed that the over expression of H-ras or v-sis/PDGF-B up-regulated the activities of GnT-V to various degrees in the transfected cells. In H-ras- and PDGF-B-overexpressing cells, the activity of GnT-V was up-regulated to double the normal value. The transient expression of v-sis, which produces a protein almost identical to PDGF-B, stimulated the GnT-V activity by 80.3%, and the effect was more pronounced (increased by 182.5%) in 7721 cells with stable expression of v-sis. The stimulating effect was entirely abolished by treatment with PDGF-B antibody. The staining of asparagine-linked glycans (N-glycans) in the H-ras- and v-sis-overexpressing 7721 cells was intensified when horseradish peroxidase-labeled leucoagglutinating phytohemogglutinin was used as a probe, indicating the increased content of beta1,6GlcNAc branching on the N-glycans. The enhancement of GnT-V mRNA expression was also observed in H-ras- and v-sis- overexpressing cells, indicating that H-ras and v-sis regulated GnT-V via the transcription of GnT-V mRNA and the synthesis of GnT-V protein. The cells overexpressing H-ras and v-sis displayed some changes in metastasis-related phenotypes, including acceleration of cell growth, decline of cell adhesion to fibronectin, and an increase of cell adhesion to laminin, as well as increased invasiveness through Matrigel. These results indicated that the alteration of cell adhesion and invasion induced by oncogenes is closely related to the up-regulation of GnT-V activity and its product, beta1,6GlcNAc branching in N-glycans on the cell surface.

Transcriptional repression of p21((Waf1/Cip1/Sdi1)) gene by c-jun through Sp1 site

Previously, we found that c-jun represses the tumor suppressor p21((Waf1/Cip1/Sdi1)) (p21) gene expression. In this study, we further investigated the mechanism of the inhibitory effect of c-jun on p21. After analysis of a series of deletion and point mutants of p21 promoter, we found that Sp1-3 site (-77 and -83) relative to the transcription start site played an important role for c-jun-repressing-responsive element in the p21 promoter. Both Sp1 and Sp3 transcription factors were the key factors for this event. However, the data from electrophoretic mobility shift assay indicated that c-jun did not change the Sp1 DNA-binding affinity, suggesting that additional factors may be involved in the repression of p21 by c-jun. Furthermore, c-jun could inhibit butyrate-inducing p21 gene expression through Sp1, indicating at least one common pathway whereby p21 expression is affected by c-jun and butyrate in opposing actions. Moreover, the hyperphosphorylated retinoblastoma protein (Rb) increased in c-jun expressing cells, indicating that phosphorylated Rb may play a role in regulating Sp1 to repress p21 expression. This is the first demonstration of how housekeeping factors and oncogene product counteract the function of tumor suppressor genes to control cell cycle progression.

[Contents of general flavonoides in Epimedium acuminatum Franch. and its differently-processed products]

OBJECTIVE

Determining and comparing the contents of general flavonoides in four kinds of differently-processed products of Epimedium acuminatum.

METHOD

Determining the contents by ultraviolet spectrophotometry.

RESULT

The contents were found in the following seguence: unprocessed product, clearly-fried product, alcohol-broiled product, salt-broiled product, sheep-fat-broiled product. The average recovery rate was 96.01%, with a 0.74% RSD(n = 5).

CONCLUSION

Heating causes the contents of general flavonoides in the processed products to decrease. These processed products are still often used in clinical treatment, for the reason that the adjuvant features certain coordinating and promoting functions. The study is to be pursued further.

Regulation of phospholipase D from human hepatocarcinoma cell line by purine nucleotides and protein kinase A

The regulation of phosphatidylcholine-specific phospholipase D by purine nucleotides and protein kinase A were studied in vitro using an enzyme preparation partially purified from the membranous fraction of 7721 hepatocarcinoma cells. It was found that the enzyme activity was elevated by low concentrations of some purine nucleotides, but the activating effects were decreased when the concentrations of the nucleotides were higher. The optimal concentrations of GTP, GTPgamma[S], GDP and ATP for maximal activation were 0.1 mM, 5 microM, 1 mM and 1 mM respectively. The activation caused by 1 mM ADP was lower. The enzyme was not activated by 1 mM AMP, but significant activation was observed by the addition of 1 mM cAMP. The latter was mediated by protein kinase A, as a specific inhibitor of protein kinase A abolished the activation. There were synergic effects between ATP and GTP, ATP and PIP2, but not between ATP and GTPgamma[S], or PIP2 and GTPgamma[S]. The activating effects of GTP and ATP were abolished by neomycin, a PIP2 scavenger. These results suggest that phospholipase D is regulated by GTP-binding protein and the presence of PIP2 is required for the activation induced by GTP. Protein kinase A may be another protein kinase in addition to protein kinase C and protein tyrosine kinase which regulate the activity of phospholipase D, when the intracellular concentration of cAMP is increased.

Opposing changes in N-acetylglucosaminyltransferase-V and -III during the cell cycle and all-trans retinoic acid treatment of hepatocarcinoma cell line

The changes in N-acetylglucosaminyltransferase-V and -III (GnT-V, GnT-III) during the cell-cycle of synchronized 7721 human hepatocarcinoma cell line were investigated. Using an HPLC method to assay GnT and flow cytometry (FCM) for cell cycle analysis, it was found that GnT-V showed the highest activity, but GnT-III reached the lowest activity when G(2)/M cells were most abundant. In contrast, GnT-V declined to the minimum while GnT-III elevated to maximum when G(0)/G(1) cells were most predominant. The opposing changes were more obvious when the activities of GnT-V and GnT-III were expressed as relative activities (activity of GnT-V or GnT-III/the sum of activities of GnT-V plus GnT-IV plus GnT-III). These opposing changes of GnT-V and GnT-III during the cell cycle might result from the different regulatory mechanisms of GnT-V and GnT-III expression in the cell cycle. The alterations in the structures of cell surface N-glycans were compatible with the changes of the activities of GnTs. The results from immunocytochemistry and Northern blot showed that the protein and mRNA contents of GnT-V were not significantly changed during the cell cycle. The activity of a cell cycle regulating protein kinase, p34(cdc2) kinase, correlated to the activity of GnT-V. These findings suggested that the change of GnT-V activity in cell cycle was not the consequence of the alteration of gene transcription or enzyme protein synthesis, but might be caused by the post-translational regulation. The decrease in GnT-V and the corresponding increase in GnT-III activities were also found after the cells were treated with all-trans retinoic acid (ATRA), and the mechanism of this might be different from that in the cell cycle.

Effects of all-trans retinoic acid and epidermal growth factor on the expression of nm23-H1 in human hepatocarcinoma cells

The effects of all-trans retinoic acid (ATRA) and epidermal growth factor (EGF) on the expression of nm23-H1, a metastasis suppressor gene, were studied in a human 7721 hepatocarcinoma cell line. It was discovered that the expression of nm23-H1 mRNA was up-regulated by ATRA. This was compatible with the observation that the metastasis-associated phenotypes, such as chemotaxic cell migration and invasion, were both reduced in the ATRA-treated and nm23-H1-cDNA-transferred 7721 cells. However, ability of cells to adhere to fibronectin and laminin was not altered identically in the ATRA-treated and nm23-H1-cDNA-transfected 7721 cells. In contrast, the expression of nm23-H1 mRNA in 7721 cells was down-regulated both by the treatment with EGF and by the transfection of c-erbB-2/neu cDNA, which codes a protein homologous to the EGF receptor. EGF is a compound with biological effects opposite to those of ATRA, and c-erbB-2/neu is known to be a metastasis-promoting gene. These results reveal that the metastasis-preventing effect of ATRA may partly result from the up-regulation of nm23-H1, and the metastasis-promoting effects of EGF and c-erbB-2/neu were probably mediated in part by the down-regulation of nm23-H1.

Differential regulation of FGF-1 and -2 mitogenic activity is related to their kinetics of binding to heparan sulfate in MDA-MB-231 human breast cancer cells

The growth of the malignant human mammary MDA-MB-231 cells is stimulated by fibroblast growth factor-1 (FGF-1) but not by FGF-2. When these cells are cultured in the presence of chlorate, an inhibitor of heparan sulfate (HS) sulfation, their proliferation is stimulated by both FGF-1 and FGF-2. We analyzed the interactions of FGF-1 and FGF-2 with HS purified from the cell layer and the culture medium of control and chlorate-treated MDA-MB-231 cells. The HS from the cell layer bound FGF-1 with faster association kinetics than the HS from the culture medium, and so had a higher affinity for FGF-1. Chlorate treatment had no significant effect on the FGF-1 binding kinetics of the HS. In contrast to FGF-1, chlorate treatment of the cells significantly altered the FGF-2 binding kinetics. The HS from untreated cells possessed two binding sites for FGF-2, one with fast association kinetics (k(ass) 470,000 to 610,000 M(-1) s(-1)) and a high affinity (K(d) 46 to 70 nM) and one with slower association kinetics (k(ass) 74,000 to 100,000 M(-1) s(-1)) and a lower affinity (K(d) 290 to 400 nM). HS from chlorate-treated cells possessed just a single binding site for FGF-2 with fast association kinetics (k(ass) 270,000 to 290,000 M(-1) s(-1)) and a high affinity (K(d) 41 to 57 nM). These results show that there is a relationship between the binding kinetics of FGFs and their ability to stimulate cell growth.

Muscarinic regulation of basal versus thyrotropin-releasing hormone-induced prolactin secretion in rat anterior pituitary cells. differential roles of nitric oxide and intracellular calcium mobilization

Acetylcholine (ACh), synthesized in the pituitary, can act locally to modulate pituitary function. We used rat primary anterior pituitary (AP) cells to investigate how ACh affects pituitary prolactin (PRL) secretion in the presence or absence of known PRL regulators: thyrotropin-releasing hormone (TRH), 17beta-estradiol (E(2)) and triiodothyronine (T(3)). Cultured AP cells were prepared from ovariectomized rats and pretreated with diluent, 0.6 nM E(2), 10 nM T(3), or E(2) plus T(3) for 5 days, then challenged with various doses of ACh or muscarinic receptor agonists (oxotremorine or carbachol) and TRH (100 nM) for 20 min. Significant ACh (10(-5) M) suppression of both basal and TRH-induced PRL secretion was not evident in diluent-, E(2)- or T(3)-pretreated cells, but observed only in cells pretreated with both E(2) and T(3). Moreover, in E(2) plus T(3)-pretreated cells, oxotremorine and carbachol, like ACh (10(-7)-10(-5) M), suppressed both responses in a dose- related manner. Pertussis toxin (PTX; 100 ng/ml) as well as atropine (a muscarinic receptor antagonist; 1 mM) blocked these effects of cholinomimetics. ACh also inhibited both PRL responses elicited by drugs elevating intracellular cAMP (10 microM forskolin) or Ca(2+) (1 microM Bay K-8644) in a PTX-sensitive manner. ACh inhibition of basal PRL secretion was unaltered by intracellular Ca(2+) mobilization blockers, TMB-8 (100 microM) and thapsigargin (1 microM), but abrogated by the nitric oxide synthase inhibitor (300 microM L-NAME). ACh inhibition of TRH-induced PRL secretion was accentuated by TMB-8 and alleviated by thapsigargin or L-NAME. In summary, muscarinic inhibition of either basal or TRH-induced PRL secretion was augmented by E(2) and T(3), and involved the PTX-sensitive cAMP/Ca(2+) pathways. Furthermore, nitric oxide mediated the basal rather than TRH-induced PRL response to ACh, whereas the intracellular Ca(2+) mobilization concerned the TRH-induced rather than the basal PRL response to ACh. Thus, ACh synthesized in the AP appears to inhibit basal vs. TRH-induced PRL secretion via different mechanisms.

Changes of hepatitis B surface antigen variants in carrier children before and after universal vaccination in Taiwan

Mutants of a determinant of hepatitis B surface antigen (HBsAg) identified in vaccinated children pose a potential threat to long-term success of vaccination programs. We examined the mutants of a determinant (residues 110-160) of HBsAg in hepatitis B virus (HBV) DNA-positive children identified during previous serosurveys in Taipei undertaken just before (1984), 5 years after (1989), and 10 years after (1994) universal vaccination began. In HBV DNA-positive children from 3 surveys, the prevalence of a determinant mutants increased from 8 of 103 (7.8%) in 1984 to 10 of 51(19.6%) in 1989 and 9 of 32 (28.1%) in 1994 and was higher in those fully-vaccinated than unvaccinated (12/33 vs. 15/153, P =. 0003). Most amino acid changes of the variants clustered in residues 125-129 and 140-149. In all 27 children with detectable mutants, the mean age of those vaccinated was younger than those unvaccinated (4. 8 +/- 3.8 vs. 7.9 +/- 2.3 yrs, P <.05); and mutations occurred in a region with greatest local hydrophilicity (residues 140-149) more frequently in those vaccinated than in those unvaccinated (10/12 vs. 6/15, P =.0253). More mutated residues and more mutations at neutralizing epitopes, such as N146, C147, T148, and C149, were found in the 1994 survey. Vaccinated children may contract variant infections through vertical or horizontal transmission. Universal vaccination has accelerated an accumulation of HBsAg a determinant mutants with amino acid changes critical for immune escape in vaccinated children who became carriers, suggesting that new vaccination strategies should be considered.

Increased susceptibility to apoptosis of human hepatocarcinoma cells transfected with antisense N-acetylglucosaminyltransferase V cDNA

The antisense cDNA of N-acetylglucosaminyltransferase V (GnT-V, EC 2. 4.1.155) was constructed as pcDNA3/GnT-V-AS plasmid and transfected into 7721 cells, a human hepatocarcinoma cell line. The transfection was confirmed with Northern blot. By using HPLC and HRP-lectin staining, it was found that the cells transfected with pcDNA3/GnT-V-AS (GnT-V-AS/7721) expressed less GnT-V activity and beta-1,6-GlcNAc branching in the cell glycoproteins compared with the cells mock-transfected with the vector pcDNA3 (pcDNA3/7721). The growth rate of GnT-V-AS/7721 was decreased in serum-containing medium, while the cell death was accelerated in serum-free medium. The GnT-V-AS/7721 cells were more susceptible to the apoptosis induced by ATRA than the mock-transfected cells. This was evidenced by the obvious appearance of a hypoploid sub-G(1) fraction in the DNA histogram using FCM analysis, the more condensed new moon-type nuclei under morphological observation, and the more intensive TUNEL reaction for assaying the fragmented DNA. At the same time as GnT-V down-regulation by GnT-V-AS, an increase of another N-aceylglusaminyltransferase, GnT-III (EC 2.4.1.144), was observed, and the biological significance of this finding was discussed.

Cutaneous lymphocyte antigen is expressed on memory/effector B cells in the peripheral blood and monocytoid B cells in the lymphoid tissues

Cutaneous lymphocyte antigen (CLA) is expressed on a subpopulation of human memory T cells and is involved in the primary step of their skin homing. T cells and some B cells in the peripheral blood express CLA, but the pathophysiologic roles of CLA(+) B cells have not yet been clarified. We examined the relationships among CLA expression in B cells and immunoglobulin heavy chain subtype, the localization of CLA(+) B cells in the peripheral lymphoid tissues, and their functional binding to E-selectin. CLA was expressed on class-switched, memory B cells in the peripheral blood and tonsils as revealed by flow cytometry. Immunohistochemical staining of the lymph nodes with various types of inflammation or reactive hyperplasia showed CLA on the monocytoid B cells, which correspond to memory cells. The functional study revealed that CLA on B cells bound to E-selectin transfectants. E-selectin was detected on some of the high endothelial venules in the monocytoid B-cell-rich lymph nodes. These findings suggest that CLA is also expressed on a subset of memory/effector B cells, in addition to a subset of memory T cells. Such B cells were located in the lymph nodes or tonsils and rarely in chronic dermatitis. Therefore, CLA seems to be related to memory/effector B-cell trafficking to the lymph nodes or tonsils. According to the multistep theory, mechanisms involved in the second or third step might be different between CLA(+) B and T cells.

Thrombocytosis in children at one medical center of southern Taiwan

Thrombocytosis in children is common, but usually without symptoms. The causes of thrombocytosis in children are considered to be mostly due to infection, trauma, surgery, blood disease, prematurity, renal disease and chronic inflammation. To evaluate the incidence and etiology of thrombocytosis of the hospitalized patients, patients who were admitted to the Pediatric Department of Kaohsiung Medical College Hospital (KMCH) from October 1996 to November 1997 were studied. There were 2910 cases studied and 220 cases (127 male and 93 female) had thrombocytosis (> or = 500 x 10(9)/L) with a rate of 7.6%. The causes of thrombocytosis are infections (49.5%), Kawasaki disease (6.4%), postsplenectomy (7.8%), blood diseases (3.7%), malignancies (3.2%), renal disorders (3.2%), prematurity (3.2%), tissue damage (4.5%), chronic inflammation (1.8%), recovery from marrow suppression (1.3%), immunologic disturbances (2.2%), essential thrombocythemia (0.5%), and miscellaneous factors (3.7%). Thrombocytosis associated with multiple, simultaneous causative factors was found in 9.0% of these cases. Thrombocytosis secondary to infectious diseases or Kawasaki disease was significantly more common in children under 2 years old. The most commonly associated infectious disease was respiratory tract infection (61.1%). There were 29 children (13.2%) presenting a platelet count of more than 800,000/mm3. However, no thrombotic complications were seen in any of the children. By far, the major cause of thrombocytosis in our cases was reactive in character. Most of the thrombocytosis cases were due to infections, inflammatory diseases, or Kawasaki disease.

Alterations in glycosyltransferases during myeloid and monocytoid differentiation of HL-60 cells

HL-60, a human promyelocytic leukemia cell line, can be differentiated to myeloid lineage by all- trans retinoic acid (ATRA), dimethylsulfoxide (DMSO) and n -butyric acid (n -BA), or to monocytoid(monocytic/macrophagic) lineage by phorbol-12-myristate-13-acetate (PMA) and ganglioside GM(3). The activity alterations of N -acetylglucosaminyltransferase III and V (GnT-III, GnT-V) as well as alpha-1,6-fucosyl-tranferase (alpha1,6 Fuc T) were studied during the differentiation of HL-60 cells by the above-mentioned five inducers using the fluorescence (PA)-labeled glycan-HPLC method for GnT assays and biotin-labeled glycan-LCA affinity chromatography combined with the HRP-avidin colorimetric method for alpha1,6 Fuc T assay. It was observed that after 3 days, all three enzymes decreased in HL-60 cells induced by 1 micromol/l ATRA and 0.6 mmol/l n-BA, while GnT-III and alpha1,6 Fuc T increased, but GnT-V still decreased after induction by 1% DMSO. GnT-V and alpha1,6 Fuc T declined, while GnT-III was elevated after induction by 0.1 micromol/l PMA for 3 days. In contrast, GnT-III increased after the treatment with 50 micromol/l GM(3)for 3 or 6 days, but GnT-V was not appreciably changed and alpha1,6 FucT was elevated after 6 days of GM(3)treatment. It may be concluded that the decrease of GnT-V is the common change in myeloid differentiation and the increase of GnT-III is the general alteration in monocytoid differentiation. The changes in the activities of glycosyltransferases were consistent with the structural changes in surface N -glycans previously found in our laboratory, i.e. that the antennary number of N -glycans decreased during myeloid differentiation by ATRA, and the amount of bisecting GlcNAc in N -glycans increased during monocytoid differentiation by PMA.

Hexamethyldisiloxane film as the bottom antireflective coating layer for ArF excimer laser lithography

We demonstrate a new bottom antireflective coating (BARC) layer for ArF excimer laser lithography. The antireflective layer is composed of hexamethyldisiloxane (HMDSO) film, which is deposited by the conventional electron cyclotron resonance-plasma-enhanced chemical-vapor deposition process. We obtain the appropriate HMDSO films for BARC layers by varying the gas-flow rate ratio of oxygen to HMDSO. Such a process has several advantages: high deposition rate, low process temperature, easy film removal, and reduced cost. Measured reflectances of less than 0.5% on both Al-Si and silicon crystal substrates have been achieved and agree well with the simulated reflectances. The swing effect is shown to be significantly reduced by addition of the HMDSO-based BARC layer.

Cyno-EBV (EBV-related herpesvirus from cynomolgus macaques) induces rabbit malignant lymphomas and their tumor cell lines frequently show specific chromosomal abnormalities

Malignant lymphoma (ML) induction in rabbits by Epstein-Barr virus (EBV)-related herpesvirus of cynomolgus (Cyno-EBV) is reported. Twenty-seven of 30 (90%) rabbits inoculated intravenously with Cyno-EBV-producing simian (cynomolgus) lymphocyte cell line (Ts-B6) cells developed ML between 45 and 115 days after inoculation. The peroral inoculation of Ts-B6 cells induced ML in only 2 of 10 (20%) rabbits (75 to 85 days). Five of 6 (83%) rabbits injected with cell-free pellets from Ts-B6 cultures also developed ML (27 to 122 days). Antibody response to the viral capsid antigen of EBV was also detected in sera from rabbits inoculated with Ts-B6. ML of the large cell or mixed type infiltrated diffusely in many organs, frequently involving the spleen, liver, kidneys, heart, and less frequently the lungs, lymph nodes, brain, eyes, gastrointestinal tract, thymus, and bone marrow. A chromosomal analysis of five lymphoma cell lines established from tumor-bearing rabbits revealed the rabbit karyotype. Three of these cell lines showed the chromosomal abnormalities with 12q- or t (7p+:12q-). EBV-encoded small RNA-1 and EBV-associated nuclear antigen 1 were expressed in Ts-B6 cells, the tumor tissues, and all rabbit cell lines by in situ hybridization and by immunofluorescence tests, respectively. EBV DNA was also detected in Ts-B6 cells and rabbit lymphoma cell lines by polymerase chain reaction and Southern blot analysis. The Southern blots of EBV termini revealed oligoclonal bands in the Cyno-EBV-induced rabbit lymphomas. No lymphoma was induced by the inoculation of B95-8 (EBV-producing cells) or peripheral leukocytes from normal cynomolgus (controls). These data suggest that the high rate of lymphoma induction in rabbits may be caused not by human EBV (B95-8) but by Cyno-EBV from Ts-B6 cells. A sequence analysis of the IR1 (BamHIW) region of Cyno-EBV revealed that this region is quite similar to that of herpesvirus Macaca fascicularis 1, which is a causative agent for a monkey model of AIDS-related lymphomas. The present rabbit model of lymphoma with specific chromosomal abnormalities is very useful to clarify the role of EBV in human EBV-associated lymphoma and provides a means for studying prophylactic and therapeutic regimens.

Interference coatings based on synthesized silicon nitride

Silicon nitrides are synthesized by ion-assisted deposition with only one coating material and a nitrogen-ion-beam source. All the SiN(x) films are amorphous and mechanically strong. A wide range of refractive indices from 3.43 to 1.72 at a wavelength of 1550 nm is obtained. Near-IR antireflection coating and a bandpass filter based on the multilayers of SiN(x) and Si are demonstrated.

Primary sclerosing cholangitis in a child

Primary sclerosing cholangitis (PSC) is a rare disease in Taiwan and has not been described in Taiwanese children previously. We report a 4-year-old girl who presented with prolonged fever, eosinophilia (11%), hepatomegaly, and markedly elevated serum levels of alkaline phosphatase (3,318 IU/L) and gamma-glutamyl transpeptidase (475 IU/L). Subsequent investigations including endoscopic retrograde cholangiopancreatography and liver histology confirmed the diagnosis fo PSC. Treatment with a low dose of prednisolone for 2 months and ursodeoxycholic acid during 32 months of follow-up resulted in clinical remission and halted disease progression. A high index of suspicion is necessary for physicians to diagnose this disorder in children with chronic liver disease. Our experience in this case indicates that therapy with prednisolone and ursodeoxycholic acid may be helpful for the treatment of PSC in children, and suggests the need for more trials of combined therapy.

[Molecular typing of Taiwanese Orientia tsutsugamushi isolates by restriction fragment profile]

Scrub typhus, which is caused by Orientia tsutsugamushi, is one of the reportable diseases in Taiwan, ROC. Positive cases seemed to be increasing in recent years and our laboratory had confirmed a total of 247 cases in 1997. In this study, 71 strains of O. tsutsugamushi were isolated from heparinized blood of the patients by cell culture, and their DNA was isolated. Two-step polymerase chain reaction was then used to amplify a specific sequence from the DNA, which was digested with restriction enzymes, Hha I and Sfa NI, for typing. With this technique, 34 strains gave rise to the same profile as that of the Kuroki type, 6 as the Karp type and 2 as the Gilliam type. The remaining 28 strains produced fragment profiles different from those of types Karp, Kato, Kawasaki, Kuroki, Gilliam and Shimokoshi and, therefore, were classified as 6 new types designated Taiwan A to Taiwan F, respectively. These strains with profiles different from those of the standard Japanese strains may represent the local mutant strains.

[Immunohistochemical study of the expression of fucosylated glycoconjugates in human lung carcinoma]

Lewis X, Sialyl Lewis X and Sialyl Dimeric Lewis X are three fucosylated glycoconjugates on cell surface. With immunohistochemical method, the expression of the three structures in the original lung cancer tissues (with or without metastasis), adjacent tissues and metastatic lesions of lung carcinoma were studied. It was found that the three antigens were expressed with different intensity on the cell surface and in the cytoplasm of the lung carcinoma cell. However, there was no or only trace expression of these antigens in the adjacent tissues of lung carcinoma and normal lung tissues. Moreover, the original lesions of lung carcinoma with metastasis and/or poor differentiation expressed higher level of the three antigens than those without metastasis and/or with well or medium differentiation. Sialyl Lewis X was considered to be more closely related to the metastatic ability and differentiation of the lung carcinoma cell than the other two antigens, Lewis X and Sialyl Dimeric Lewis X. Furthermore, in the lymph nodes with lung carcinoma cell metastasis, there were expression of the three antigens with different degree, while in those lymph nodes without lung carcinoma cell metastasis, there was no expression of the three antigens.

Differential reactivity of the rat S100A4(p9Ka) gene to sodium bisulfite is associated with differential levels of the S100A4 (p9Ka) mRNA in rat mammary epithelial cells

Elevated intracellular levels of S100A4, an S100-related calcium-binding protein, induce metastatic capability in benign mammary tumor-derived epithelial cells and in transgenic mice bearing oncogene-induced benign mammary tumors. The S100A4(p9Ka) gene in rat mammary epithelial cells expressing low levels of S100A4 yields a reduced number of fragments upon digestion with the methylation-sensitive restriction enzyme, HpaII, compared with the gene from high S100A4-expressing cells. Genomic sequencing of two potential regulatory elements in the S100A4 gene, an intronic enhancer and TATA box region, revealed that in low S100A4-expressing cells, most cytosine bases exhibited high levels of resistance to conversion to thymine by sodium bisulfite. In derivative cell lines, which express high levels of S100A4, only a small number of cytosine bases were resistant to treatment with sodium bisulfite. In contrast, cytosine bases in the DNA surrounding an upstream regulatory region, which binds inhibitory GC factor in the low-expressing cell lines, are sensitive to conversion to thymine by sodium bisulfite in both low- and high-expressing cell lines. The results suggest that the rat S100A4 gene is maintained in a different state in the low-expressing cell lines and that this state might be a consequence of the pattern of methylation in this regulated gene that does not contain a CpG island.

Alteration in transcripting the gene encoding the delta-opioid receptor in rat brain is not underlying the development of tolerance to [D-Ala2,D-Leu5] enkephalin

Previous study has demonstrated that chronic treatment of [D-Ala2,D-Leu5] enkephalin (DADLE) induces profound down-regulation of delta opioid receptor in rat brain. We further examined whether this down-regulation of receptor was due to a decrease in the transcription of gene encoding delta-opioid receptor (DOR-1). Rats received daily i.c.v. injection of DADLE for 1, 3, or 5 days and developed significant tolerance to the antinociceptive effect of DADLE after one-day treatment. We measured the level of mRNA in rat brain tissues using in situ hybridization. No significant changes in the mRNA levels of the cortex, striatum, hippocampus, and thalamus on any examined days were found as compared to those of rats received sham operation only. There is only a transient decrease of DOR-1 mRNA level in midbrain region that occurred after a three-day treatment. Thus, the result of this study did not suggest that alteration in transcription of gene-encoding delta-opioid receptor was responsible for the down-regulation of delta-opioid receptor associated with the development of tolerance to DADLE.

[Changes with cell cycle of N-acetylglucosaminyl transferase III, IV and V in 7721 human hepatocarcinoma cells]

In order to investigate the changes of N-acetylglucosaminyl transferase (GlcNAc-T) III, IV and V in cell cycle, the synchronization of 7721 human hepatocellular carcinoma cells was performed using serum hunger method. The percentages of cells in different phases during cell cycle were measured by flow cytometry (FCM) and the cell cycle was checked by determining the activity of cellular p34cdc2 kinase. It was found that the activities of GlcNAc-T III increased in G0/G1 cell peak phase and had correlation with the cell percentage of G0/G1 phase (r = 0.760, P < 0.05), while GlcNAc-T V showed the highest activity when G2/M cells were most abundant and had an apparent correlation with the cell percentage of G2/M phase (r = 0.868, P < 0.001). The changes of GlcNAc-T IV activity seemed not related to the cell cycle. The changes in opposite directions of relative activities (percentage of total GlcNAc-T III, IV, V) of GlcNAc-T III and GlcNAc-T V were observed during cell cycle (r = -0.951, P < 0.001), suggesting that these two enzymes might be regulated differently and functioned oppositely in the cells: GlcNAc-T V may be related to the proliferation of 7721 cells, while GlcNAc-T III may be related to the non-mitotic silence phase of the cells, or, it may be a factor against proliferation. Immunohistochemical results showed that the protein content of GlcNAc-T V was not significantly changed during cell cycle, and had no correlation with the activity of GlcNAc-T V, suggesting that the changes of GlcNAc-T V activity in cell cycle might not be resulted from the alteration of enzyme protein synthesis. The correlation between the activities of GlcNAc-T V and p34cdc2 kinase (r = 0.752, P < 0.05) was observed in cell cycle, implicating that GlcNAc-T V might possibly be regulated by p34cdc2 kinase.

[Effects of sex hormones on the expression of placenta form glutathione S-transferase (GST-P) in rat induced hepatocarcinoma]

Using Solt-Farber method for the induction of rat hepatocarcinoma, the changes of the activity of glutathione S-transferase (GST) and the content of placenta form GST (GST-P) were studied during hepatocarcinogenesis, then the effects of sex hormones on the hepatic expression of GST-P were observed using immunohistochemical method. The results showed that both GST activity and GST-P content began to increase at the 3rd week, and reached the highest level at the 5th week (Table 1). Therefore, the 5th week was selected for the study of GST-P expression in the livers of rats treated with different protocol (Fig. 1). It was found that GST-P was highly expressed in the livers of sham-castrated male rats after chemically induced hepatocarcinoma (PLATE I, Fig. 1A, Table 2). When estradiol was administrated to these rats, both the number and area of GST-P positive(+) foci decreased significantly (PLATE I, Fig. 1B, Table 2). While testosterone was administrated instead of estradiol, the decrease of the area but slight increase of the number of GST-P positive foci were found (PLATE I, Fig. 1C, Table 2). After orchiectomy, the areas of GST-P (+) foci in carcinogen treated liver of male rats were smaller than those in rats with sham-orchiectomy and same carcinogen treatment (PLATE I, Fig. 2A, B, Table 3). When the orchiectomized male rats were administrated with estradiol, the areas of GST-P (+) foci decreased further (PLATE I, Fig. 2C, Table 3). In contrast, after ovariectomy of the female rats, the areas of GST-P (+) foci in carcinogen treated livers were slightly increased as compared with those in the rats with sham-ovariectomy and same carcinogen treatment (PLATE I, Fig. 2D, E, Table 3). While the ovariectomized female rats were administrated with testosterone, the areas of GST-P (+) foci increased further (PLATE I, Fig. 2F, Table 3). Regardless of whether castrations were done or not, GST-P expression in livers of male rats induced hepatocarcinoma was higher than in livers of female rats (PLATE I, Fig. 2A, B, D, E, Table 3). These results indicated that estrogen may inhibit but androgen may promote the GST-P expression in the rat liver during hepatocarcinogenesis. This may be related to the higher incidence of liver carcinoma in male than in female.

Television and music video exposure and risk of adolescent alcohol use

OBJECTIVE

Alcohol use is frequently portrayed in television programming and advertising. Exposure to media portrayals of alcohol use may lead to increased drinking. To address this issue, we examined prospectively the associations between media exposure and alcohol use in adolescents.

DESIGN

Prospective cohort study. Setting. Six public high schools in San Jose, California. Participants. Ninth-grade students (N = 1533; mean age = 14.6 years).

OUTCOME MEASURES

Students reported hours of television, music video, and videotape viewing; computer and video game use; and lifetime and past 30 days' alcohol use at baseline and 18 months later. Associations between baseline media exposure and subsequent alcohol use were examined with multiple logistic regression.

RESULTS

During the 18-month follow-up, 36.2% of baseline nondrinkers began drinking and 50.7% of baseline drinkers continued to drink. Onset of drinking was significantly associated with baseline hours of television viewing (odds ratio [OR] = 1.09; 95% confidence interval [95% CI] = 1.01-1.18), music video viewing (OR = 1.31; 95% CI = 1. 17-1.47), and videotape viewing (OR = 0.89; 95% CI = 0.79-0.99), controlling for age, sex, ethnicity, and other media use. Computer and video game use was not significantly associated with the subsequent onset of drinking. Among baseline drinkers, there were no significant associations between baseline media use and maintenance of drinking.

CONCLUSIONS

Increased television and music video viewing are risk factors for the onset of alcohol use in adolescents. Attempts to prevent adolescent alcohol use should address the adverse influences of alcohol use in the media.