Effect of Pluronic on cellular uptake of cationic liposomes- mediated antisense oligonucleotides

Cationic liposomes modified by different Pluronic block copolymers were prepared. The influence of Pluronic on the cellular uptake of antisense oligonucleotides (ODN) based on cationic 3beta[N-(N', N'-dimethylaminoethan)-carbamoyl] cholesterol (DC-Chol) liposomes was studied by flow cytometric analysis. It showed that DC-Chol liposomes containing Pluronic gave 1.7-2.3 times higher capacity of cellular uptake of ODN, despite the diminution of ODN loading efficiency. The level of improvement by Pluronic is related to the hydrophobic propylene oxide (PO) units Pluronic contains as well as the lipophile/hydrophile value of the molecule. This preliminary study indicated that modifying liposomes with another excipient is a useful pharmaceutical technique to improve ODN delivery.

[Second sampled survey on the distribution of human parasites in Zhejiang Province]

OBJECTIVE

Twenty-six species of human parasites were recorded in Zhejiang Province in 1987-1989 as a part of the national investigation on the distribution of human parasites, and the total prevalence was 80.2%. In order to find out possible changes on the composition of parasite species and decrease of prevalence after control intervention particularly mass chemotherapy in the past years and provide evidence for an improved control strategy, the second sampled survey was carried out from 1998 to 1999.

METHODS

Ten counties were identified randomly out of 28 counties where the last survey was conducted following the same sampling method. Same technics were used for case detection and data processing.

RESULTS

The total infection rate in a sample of 15,698 was 22.84% was 22.84% in 30 investigation spots in 10 counties, and 17 species of parasites were revealed. The overall prevalence was reduced by 71.51% in comparison to that of 1989, and the number of parasite species was 17, 9 less than that of the last investigation.

CONCLUSIONS

The prevalence of human parasites has greatly declined in this province due to the socioeconomic development and adoption of comprehensive control measures focusing on mass chemotherapy in the past decade.

Expressions of Lewis antigens in human non-small cell pulmonary cancer and primary liver cancer with different pathological conditions

The expressions of three X series Lewis antigens, including Lewis X (Le(x)), sialyl Lewis X (SLe(x)) and sialyl dimeric Lewis X (SDLe(x)) were studied with immuno-histochemical methods in human non-small cell pulmonary cancer (NSCPC) and primary liver cancer (PLC) with different pathological conditions. The Lewis antigens are mainly expressed on the cell surfaces, medially or slightly in the cytoplasm, but not in the cell nuclei of the cancer tissues. The regions adjacent to the cancer tissues do not express any Lewis antigens. The positive rates of these antigens in NSCPC were within the range of 75% to approximately 86%. There was no apparent difference in positive rates between the cases with different differentiation and the presence or absence of metastasis in peripheral lymph nodes, nor among the three antigens, except that the positive rate of SDLe(x) was lower (about 56%) in the cases with well/medium differentiation and without metastasis. However, the expression-intensities (SI indexes) of all three antigens were significantly higher in the samples of poor differentiation and with metastasis as compared to those with well/medium differentiation and without metastasis. The two sialyl Lewis antigens increased more significantly than non-sialylated Le(x). The expressions of these antigens were also observed in the peripheral lymph nodes with metastasis, but not in those without metastasis. The positive rates of Le(x), SLe(x) and SDLe(x) in human primary liver cancer were 83.3%, 88.9% and 77.8%, respectively. In the cases with cancer cell thrombosis (CCT) in portal vein (an index of metastasis), the expressions of all these three antigens were stronger than those in the cases without CCT. SLe(x) was the most abundant and most highly increased Lewis antigen on the surface of NSCPC and PLC, especially in the cases with poor differentiation and metastasis. In the study of the enzymatic basis of the increased Lewis antigens in PLC by using Northern blot, it was found that the level of alpha1,3 FucT-III/VI mRNA in PLC tissues was much higher than that in the adjacent regions, and more significantly higher in the cancer tissues from patients with CCT in portal vein. In contrast, the expression of alpha1,3 FucT-VII was rather low in cancer tissues and not different from the adjacent regions in spite of the presence or absence of CCT. These results reveal that the SLe(x) in PLC is mainly synthesized by alpha1,3 FucT-III/VI (especially VI) and is the most important Lewis antigen involved in the metastasis of PLC.

Effects of lentinan on broiler splenocyte proliferation, interleukin-2 production, and signal transduction

Lentinan (LEN) is an intensively studied beta-glucan that has been shown to have immunostimulating and antitumor functions. However, it currently is not used in veterinary practice and animal production. This study was conducted to investigate the impacts of LEN on broiler splenocyte proliferation, interleukin-2 (IL-2) production, and to explore its effects on receptor signal transduction by determining signaling molecules, including nitric oxide (NO), cytosolic-free Ca2+, cytosolic cyclic adenosine monophosphate (cAMP), and cyclic guanosine monophosphate (cGMP). The results showed that compared to the control all three measured doses, including 40, 80, and 160 microg/mL LEN, increased splenocyte proliferation and IL-2 production (P < 0.05). Lentinan increased splenocyte NO production and cytosolic-free calcium concentration in a dose-dependent manner (P < 0.001). After incubating splenocytes for 20 min, LEN increased intracellular cAMP and cGMP concentrations at a dose of 80 and 160 microg/mL, respectively. However, after incubating the splenocytes for 60 min, LEN had no effect on cytosolic cAMP and cGMP concentration irrespective of the LEN dosage. Those results indicated that LEN had immunostimulatory effects on splenocytes by increasing splenocyte proliferation and IL-2 production and by activating splenocyte receptor signal transduction.

Effect of circumferential undercut placement in the root canal wall on the retention of a tapered post in large and small root canals

OBJECTIVES

This study examined the influence of root canal space and circumferential undercut placement in the dentine wall on the retention of a prefabricated Root Keeper post.

METHODS

Twenty-four extracted single-rooted teeth, having narrow root canal spaces, were decoronated, treated endodontically, and then centrally embedded in resin blocks. All canal spaces were prepared with a no. 2 Peeso reamer to an 8mm depth, and half the specimens were successively treated with a no. 3 Peeso to depths of 5 and 8mm for the small canal group (SC) and large canal group (LC), respectively. An L-type keeper post (Aichi Steel Co.) was luted to each canal with resin cement. The assembly was thermocycled 2000 times (4-60 degrees C), and post retention was measured. Afterwards the dislodged post with the intact structure was sandblasted, and the canal was cleaned and slightly undercut using an inverted cone bur. Six treated posts were recemented for both grooved large canal (GLC) and grooved small canal (GSC) groups, and the repaired retentive strengths were measured.

RESULTS

Keeper posts cemented in SC (84.26+/-31.85N) showed better (p<0.05) retention than those cemented in LC (41.92+/-22.36N). Interestingly, the repaired strengths of the recemented post increased in both GSC (104.29+/-11.89N) and GLC (96.65+/-6.91N). All posts, except for one in the GLC, failed at the keeper-post joint.

CONCLUSIONS

Prefabricated Root Keeper posts had lower retentive strength in roots with a large canal space. Placement of a circumferential undercut in the root canal wall significantly enhanced the retention of the short tapered posts.

Effects of Chinese herbal polysaccharides on the immunity and growth performance of young broilers

Two trials were conducted to study the effects of two Chinese herbal polysaccharides [achyranthan (ACH), a low-molecular-weight polysaccharide, and astragalan (APS), a high-molecular-weight polysaccaride] on the immunity and growth performance of young broilers. Trial 1 was a 28-d growth assay, in which 7-d-old broilers (n = 240) were randomly allotted to one of three dietary treatments, with eight replicate pens per treatment and ten chickens per pen. Dietary treatments included a control corn-soy-fishmeal (Treatment 1), a diet with 200 mg/kg APS (Treatment 2), and a diet with 200 mg/kg ACH (Treatment 3). Blood samples were collected by cardiac puncture on Days 7, 14, 21, and 28 for determination of serum parameters, and chickens were killed on Day 28 to measure immune organ indexes. Trial 2 was an in vitro trial to study the effects of different concentrations of polysaccharides on broiler splenocyte functions. In Trial 1, feeding either APS or ACH had no significant effects on growth performance of broilers relative to the control. However, compared to the control, feeding ACH significantly increased microhemagglutination inhibition (HI) antibody titers, bursa of Fabricius index, serum albumin, serum calcium, and nitric oxide (NO) concentrations at Day 28 (P < or = 0.05). In Trial 2, both polysaccharides showed significant immunostimulating effects. They increased NO and interleukin-2 (IL-2) production of splenocytes and enhanced splenocyte proliferation in a dose-dependent manner (P < 0.05). Those results indicate that the immunostimulating effects of APS are not as pronounced as those of ACH. Achyranthan showed immunostimulating effects in both the growth assay and in vitro studies. Therefore, ACH may be a Chinese herbal polysaccharide that has the potential to be used as a feed additive to improve broilers' immunity.

Analysis of lewis antigens on cell surface and alpha1,3 fucosyltransferase subtypes in H7721 human hepatocarcinoma cells

The expressions of Lewis antigens on H7721 human hepatocarcinoma cells were detected with monoclonal antibodies and flow-cytometry. It was found that H7721 mainly expressed SLex, and a small amount of SDLex, but Lex and SLea was negligible. The monoclonal antibody of SLex (KM93) significantly blocked the adhesion of H7721 cells to human umbilical vein epithelial cells, as well as cell migration and invasion, but the blocking effect of SDLex antibody (FH6) was not statistically significant. The expressions of five subtypes of alpha1,3fucosyltransferases (alpha1,3FucTs), the enzyme responsible for the fucosylation step in Lewis antigen synthesis, were also studied using real-time RT-PCR. The expression of FucT mRNAs were FucT-IV > FucT-III > FucT-VI > or = FucT-VII > FucT-IX. FucT-VI is supposed to be the main enzyme responsible for the synthesis SLex and SDLex. FucT-VII and III may also participate in SLex synthesis. The absence of FucT-IX expression and FucT-III not being the rate-limiting enzyme for SLea synthesis may be the reasons for the negligible expressions of Lex and SLea on the cell surface, respectively.

Bone morphogenetic proteins are involved in fetal kidney tissue transplantation-induced neuroprotection in stroke rats

Both bone morphogenetic proteins (BMPs) and glial cell line-derived neurotrophic factor (GDNF) reduce ischemia-induced cerebral injury in rats. Intracerebral transplantation of fetal kidney tissue, which normally expresses BMPs and GDNF during development, reduces ischemic injury in cerebral cortex. In this study, we tested the hypothesis that BMP is involved in this neuroprotective response. Fetal kidney tissue was cut into small pieces and transplanted into cortical areas adjacent to the right middle cerebral artery (MCA) in adult rats. In situ hybridization of brain indicated that these fetal kidney transplants contained high levels of BMP-7 mRNA three days after grafting. Immunohistochemical analysis of grafted brain showed co-localization of BMP-7 and PAX-2 immunoreactivity in the graft, suggesting that these transplants contained BMP protein. Some animals were grafted with fetal kidney tissue after intraventricular administration (ICV) of the BMP antagonist noggin (1 micro g) or after vehicle, followed by MCA ligation for 60 min. Animals receiving fetal kidney tissue transplantation developed significantly less body asymmetry, as compared to stroke animals that either did not receive transplantation or received fetal kidney grafts and noggin pretreatment. Analysis of these brains after triphenyltetrazolium chloride staining showed that fetal kidney tissue transplantation reduced the volume of infarction in the cerebral cortex. Noggin pretreatment reduced the protection induced by fetal kidney grafting, although noggin itself did not cause increase in cerebral infarction. Eight hours after ischemia, brain homogenates were obtained from grafted and control animals to assay caspase-3 enzymatic activity. This analysis demonstrated that fetal kidney grafts significantly reduced ischemia-induced caspase-3 activity. Reduction of caspase-3 activity could also be antagonized by noggin pretreatment. In conclusion, our data suggest that fetal kidney transplantation reduces ischemia/reperfusion-induced cortical infarction and behavioral deficits in adult rats, which are, at least partially, mediated through the effect of BMPs from the transplants.

Hepatitis B virus infection in children and adolescents in a hyperendemic area: 15 years after mass hepatitis B vaccination

BACKGROUND

Hepatitis B virus (HBV) infection is hyperendemic in Taiwan. Before universal HBV immunization was started in Taiwan in 1984, the carrier rate for hepatitis B surface antigen (HBsAg) was 15% to 20% in the general population.

OBJECTIVE

To quantify the population impact of a mass vaccination program for HBV 15 years after its implementation.

DESIGN

Descriptive analysis of serologic markers of HBV in healthy children and adolescents.

SETTING

Chung-Cheng District, Taipei City, Taiwan, in 1999.

PARTICIPANTS

1357 persons younger than 15 years of age, who were born after the implementation of universal HBV vaccination, and 559 persons 15 to 20 years of age, who were born before the program began.

MEASUREMENTS

Repeated serologic surveys similar to those done before and 5 and 10 years after the national vaccination program was implemented. All participants were tested for serum HBsAg, its antibody (anti-HBs), and hepatitis B core antibody (anti-HBc).

RESULTS

During the 15 years since the vaccination program was implemented, the prevalence of HBsAg among persons younger than 15 years of age decreased from 9.8% in 1984 to 0.7% in 1999; among persons 15 to 20 years of age, the 1999 prevalence of HBsAg was 7% (P < 0.001). Hepatitis B core antibody seropositivity, which represents HBV infection, was found in 2.9% of persons younger than 15 years of age and in 20.6% of persons 15 to 20 years of age (P < 0.001); in the same age groups, the rate of anti-HBs seropositivity was 75.8% and 70.7%, respectively (P = 0.02).

CONCLUSIONS

Universal vaccination significantly decreased the HBV carrier rate and infection rate among children and adolescents born since the program began. By decreasing the carrier pool, continuation of the national HBV immunization program should prevent HBV infection in the children of Taiwan, and, subsequently, adults as well.

[Determination of impurity elements in alloy aluminum by ICP-AES]

A method for the determination of Cr, Zn, Fe, Mn, Ti, Cu and Mg impurity elements of alloy aluminum of ICP-AES was studied. Working conditions were optimized. The method is simple, rapid, precise and convenient. The relative standard deviation is less than 6.3%. The recovery is 94%-105%. The results are satisfactory.

Congenital generalized lipodystrophy in a 4-month-old infant

Congenital generalized lipodystrophy (CGL, Berardinelli-Seip syndrome) is a rare autosomal recessive disorder with a clinical presentation of paucity of adipose tissue, muscular hypertrophy, organomegaly, and insulin-resistant diabetes. A 4-month-old Taiwanese female infant had hepatosplenomegaly and low body weight gain despite a voracious appetite. Hypermetabolism, hyperhidrosis, loss of subcutaneous fat, muscular hypertrophy, acanthosis nigricans, hypertrichosis, and marked hypertriglyceridemia were also noted. Liver histology revealed fatty change and portal-to-portal bridging fibrosis. Clinical features, serum biochemistry, and liver histology were compatible with the diagnosis of CGL. She was given a special diet characterized by calorie restriction and partial substitution of long-chain triglycerides with medium-chain triglycerides. The serum triglyceride concentration subsequently decreased. This present case suggests that extensive fatty infiltration and subsequent cirrhosis of the liver may be the earliest complication of CGL.

Bone morphogenetic protein-6 reduces ischemia-induced brain damage in rats

BACKGROUND AND PURPOSE

Bone morphogenetic protein-6 (BMP6) and its receptors are expressed in adult and fetal brain. Receptors for BMP6 are upregulated in adult brain after injury, leading to the suggestion that BMP6 is involved in the physiological response to neuronal injury. The purpose of this study was to determine whether there was a neuroprotective effect of BMP6 in vivo and in vitro.

METHODS

Lactate dehydrogenase and microtubule-associated protein-2 (MAP-2) activities were used to determine the protective effect of BMP6 against H(2)O(2) in primary cortical cultures. The neuroprotective effects of BMP6 were also studied in chloral hydrate-anesthetized rats. BMP6 or vehicle was injected into right cerebral cortex before transient right middle cerebral artery (MCA) ligation. Animals were killed for triphenyl-tetrazolium chloride staining, caspase-3 immunoreactivity and enzymatic assays, and TUNEL assay. A subgroup of animals were used for locomotor behavioral assays.

RESULTS

Application of H(2)O(2) increased lactate dehydrogenase activity and decreased the density of MAP-2(+) neurons in culture. Both responses were attenuated by BMP6 pretreatment. Complementary in vivo studies showed that pretreatment with BMP6 increased motor performance and generated less cerebral infarction induced by MCA ligation/reperfusion in rats. Pretreatment with BMP6 did not alter cerebral blood flow or physiological parameters. There was decreased ischemia-induced caspase-3 immunoreactivity, caspase-3 enzymatic activity, and density of TUNEL-positive cells in ischemic cortex in BMP6-treated animals.

CONCLUSIONS

BMP6 reduces ischemia/reperfusion injury, perhaps by attenuating molecular events underlying apoptosis.

[GnT-V overexpression in human hepatocarcinoma cells affects its migration and expression of cell adhesion molecules]

The purpose of this paper is to study the effect of N-acetylglucosaminyltransferase V (GnT-V) overexpression on the migration of 7721 cells and its mechanism. The abilities of migration of both 7721 cells transfected with GnT-V cDNA and 7721 cells transfected with pcDNA3 was detected, the expressions of integrin and E-cadherin which are important adhesion molecules on surface membrane and closely related to the abilities of invasion and metastasis. Cell migration abilities were measured by the agarose drop explant method. Flow cytometric analysis (FACS) was applied to determine the relative amounts of integrin alpha 5 and beta 1 subunits on the cell surface while RTPCR was carried out to determine the expression of their mRNA. The expression of E-cadherin was examined by the immunocytochemical ABC method. Western blot analysis was carried out to examine the expression of beta-catenin. GnT-V overexpression enhanced evidently the migration ability of 7721 cells and increased the amount of integrin alpha 5 subunit to 2.9 times of that of control while the amount of beta 1 subunits was not significantly changed. Besides, the expressions of E-cadherin and beta-catenin were enhanced at different levels in GnT-V/7721 cells compared with mocked. The results suggested that the overexpression of GnT-V related to the production of N-linked sugar chains could promote the expressions of integrin, E-cadherin and beta-catenin on 7721 cells so that the migration ability of tumor cells was enhanced.

Structural alterations of sugar chains in urine fibronectin from bladder cancer patients and its enzymatic mechanism

PURPOSE

To study the structural alterations of asparagine-linked sugar chains (N-glycans) on urine fibronectin (Fn) from bladder cancer (BCa) patients and its enzymatic mechanism.

METHODS

Eight pairs of urine samples from eight BCa patients pre-operation and 3 months post-operation (which proved to be normal) were collected, and the Fn in the urine samples was purified with an anti-Fn antibody affinity column. Different lectins labeled with horseradish peroxidase (HRP) were used as probes to bind the glycans of purified Fn immobilized on membrane. Enhanced chemiluminescence (ECL) reagent was adopted to estimate the activity of the bound HRP as a measure of the binding affinity of the Fn glycans to lectins, and expressed as luminescent light units (LLU). The enzymatic mechanism of the structural alteration of N-glycans in BCa Fn was studied by determination of GnT activities using the HPLC method and fluorescent-labeled substrate.

RESULTS

The mean LLU of BCa Fn was only 18.1% of the normal samples when Con A-HRP were used as probes, while the mean LLU of the BCa group was 3.34 times and 3.26 times higher than normal for the DSA-HRP and WGA-HRP probes, respectively. The individual data of the patients did not overlap between the BCa sample and normal counterparts, indicating that the positive rates were 100%, regardless of which lectin-HRP was used. These results reveal that the antennary number and bisecting GlcNAc structure are increased in the N-glycans of urine Fn from BCa assessed according to the binding specificity of ConA, DSA, and WGA. In addition, the binding affinities of urine Fn with DSA and WGA were correlated to pathological stage, and the affinity of Fn with WGA was also correlated with pathological grade. The results of GnT determination showed that GnT-III, IV, and V in BCa tissues increased by 34.0, 18.1, and 1.6 times, respectively, in normal bladder tissues which were at least 5 cm away from the BCa of the same bladder. These findings were compatible with the structural changes of N-glycans in BCa Fn, since GnT-III and GnT-IV/V are responsible for the synthesis of bisecting GlcNAc and the increase of antennary number in N-glycans, respectively.

CONCLUSIONS

(1) The highest elevation of GnT-III and the close relationship between the WGA binding of BCa Fn with the pathological stage and grade of BCa indicate that the increase of bisecting GlcNAc in N-linked glycans contributes more to the malignant behavior of BCa than the increase of GnT-IV, GnT-V, and the antennary number. (2) The correlation of altered activities of bladder GnTs with the abnormal structures of urine Fn in BCa patients indicates that the urine Fn is synthesized in the bladder. (3) The lectin-HRP assay for analyzing the structure of N-glycans in urine Fn may be used as a simple and accurate diagnosis method for BCa in the future.

Pathotypes of Pyricularia grisea in Rice Fields of Central and Southern China

Blast, caused by the fungal pathogen Pyricularia grisea, is the most devastating disease of rice worldwide. Knowledge of the pathotype composition of the pathogen in rice fields is essential for rational deployment of resistance genes in rice breeding programs. In this study, we assayed the pathotypes of the pathogen populations using samples recently collected from 13 major rice-growing provinces of central and southern China. In all, 792 single spore isolates were tested for pathogenicity reactions using 13 host differentials consisting of six indica and seven japonica near-isogenic lines (NILs). The compositions of the pathogen populations were complex; 48 pathotypes were identified with the indica NILs, 82 pathotypes were detected with the japonica NILs, and a total of 344 pathotypes were identified with both indica and japonica NILs. There were large differences in distribution of the pathotypes among the different rice-growing areas. Even neighbor provinces seemed to differ sharply in types and frequencies of the most prevalent pathotypes. There was also a large difference in the frequencies of the isolates producing compatible reactions on the NILs, indicating the difference in frequencies of avirulence genes in the pathogen populations. The data provided very useful information for formulating strategies for improving blast resistance in rice breeding programs.

Bacterial cholangitis in patients with biliary atresia: impact on short-term outcome

Bacterial cholangitis (BC) is a common complication in patients with biliary atresia (BA) and is characterized by fever, acholic stools and positive blood cultures. The diagnosis is often empirical because the yield of blood cultures is low. It is difficult to differentiate BC from other febrile episodes. In order to characterize the clinical and laboratory features of BC in patients with BA, identify risk factors, and correlate cholangitis with outcome, 37 patients with BA from 1993 to 1998 who underwent a Kasai operation in our hospital were studied. The follow-up period ranged from 6 to 59 months. A total of 107 febrile episodes were documented in these patients. The diagnostic criteria for cholangitis were fever, increased jaundice, or acholic stools. The clinical features, laboratory data, results of bacterial cultures, and outcomes were analyzed retrospectively. A total of 107 febrile episodes, including 78 bouts of cholangitis and 29 non-cholangitis infections, were found in 34 patients. Patients with BC had higher postoperative bilirubin levels (P = 0.02) and less frequent use of prophylactic antibiotics (P = 0.05) than those with non-cholangitis infections. Abnormal white blood cell counts (> 12,000 or <4,000 mm3) tended to be present in patients with BC (P = 0.08). There were no statistical differences in the risk factors and laboratory data between culture-positive (n = 16) and -negative (n = 62) cholangitis cases. The occurrence of cholangitis significantly reduced survival in both patients with good (P = 0.03) and inadequate bile flow (P = 0.03). All 9 patients who had never had cholangitis survived during the follow-up period. Repeated attacks of BC further decreased survival probability. The responsive organisms were mainly enteric bacteria, including Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumanni, and Salmonella typhi. The sensitivity tests justified empirical therapy with ceftriaxone. The effectiveness of prophylactic trimethoprim-sulfamethoxazole or neomycin warrants further studies. BC was a highly prevalent postoperative complication in patients with BA, especially those with inadequate bile drainage. It significantly affected early mortality. Aggressive and complete treatment with empirical ceftriaxone was appropriate.

Progressive familial intrahepatic cholestasis with high gamma-glutamyltranspeptidase levels in Taiwanese infants: role of MDR3 gene defect?

MDR3 P-glycoprotein mediates canalicular phospholipid transport in hepatocytes. Defects in the MDR3 gene have been found to cause a subtype of progressive familial intrahepatic cholestasis (PFIC) with high gamma-glutamyltranspeptidase (GGT) levels. Affected children develop proliferation of biliary epithelium, portal inflammation, and biliary cirrhosis. The frequency of MDR3 mutations in patients with high GGT-PFIC is unclear. There have been no Asian patients reported to carry MDR3 mutations. To determine the role of MDR3 defects in chronic cholestatic patients, we studied six Taiwanese children from five families who presented high GGT-PFIC among 47 patients with infantile onset chronic intrahepatic cholestasis. Sequence analysis of MDR3 cDNA from liver tissues was performed. Only one patient had mutation in the MDR3 gene. This patient had a homozygous 719-bp deletion (nucleotide 287 to 1005) of liver cDNA encompassing exon 5 to 9 and leading to protein truncation. The onset age was 1 y in contrast with the other five patients who presented neonatal cholestasis. Four patients without mutation, including one sibling pair, exhibited histologic features of prominent portal fibrosis leading to advanced biliary cirrhosis that were indistinguishable from the case of MDR3 mutation. We concluded that mutations in MDR3 accounted for approximately 2% (1/47) of infantile onset chronic cholestasis in Taiwan. Those patients presenting high GGT-PFIC with early onset cholestasis but without MDR3 mutation probably had inheritable disorders remaining to be clarified.

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.