Expression of MUC2, MUC5AC and MUC6 apomucins in carcinoma, dysplasia and non-dysplastic epithelia of the gallbladder

To date, nine apomucins have been characterized and their expression in malignant and premalignant lesions is under evaluation. The purpose of this study was to characterize immunohistochemically the expression of MUC2 (colonic/ intestinal type), MUC5AC (gastric surface type), and MUC6 (pyloric gland type) apomucins in 55 patients with gallbladder carcinoma (10 with in situ carcinoma, 45 with invasive carcinoma), 20 patients with gallbladder dysplasia, and 15 patients with non-dysplastic gallbladder. MUC2 was expressed mainly in 'goblet type' cells. The frequency was increased in non-dysplastic gallbladder (47%), dysplasia (75%), and in situ carcinoma (100%), and decreased in invasive carcinoma (58%). Carcinoma cells expressing MUC2, which were usually distributed at superficial areas, and well-differentiated carcinoma expressed MUC2 more extensively than moderately and poorly differentiated ones. MUC5AC was frequently expressed in gallbladder irrespective of non-dysplastic epithelia, dysplasia and carcinoma. MUC5AC was expressed also in carcinoma cells at deeply invasive sites. MUC6 was expressed frequently in pseudopyloric gland metaplasia as well as dysplasia and carcinoma. In conclusion, non-dysplastic gallbladder has a similar phenotype to gastric pyloric mucosa. Gallbladder carcinoma exhibits both intestinal and gastric surface phenotypes in the early stage of carcinogenesis, with the gastric surface phenotype dominant in invasive carcinoma.

Intravenous calcitriol regresses myocardial hypertrophy in hemodialysis patients with secondary hyperparathyroidism

To evaluate the response of circulating intact parathyroid hormone (iPTH) on myocardial hypertrophy in hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT), echocardiographic and neurohormonal assessments were performed over a 15-week period in 15 HD patients with SHPT before and after calcitriol treatment and 10 HD control patients with SHPT not receiving calcitriol therapy. We prospectively studied a group of 15 patients with significantly elevated iPTH levels (iPTH >450 pg/mL) receiving calcitriol (2 microg after dialysis twice weekly). Clinical assessment, medication status, and biochemical and hematological measurements were performed once a month. Throughout the study, calcium carbonate levels were modified to maintain serum phosphate levels at less than 6 mg/dL, but body weight, antihypertensive medication, and ultrafiltration dose remained constant. In patients treated with calcitriol, an adequate reduction of iPTH levels was found (1,112 +/- 694 v 741 +/- 644 pg/mL; P < 0.05) without changes in values of serum ionized calcium (iCa++), phosphate, or hematocrit. Blood pressure (BP), cardiac output (CO), and total peripheral resistance (TPR) did not significantly change. After 15 weeks of treatment with calcitriol, M-mode echocardiograms showed pronounced reductions in interventricular wall thickness (13.9 +/- 3.6 v 12.8 +/- 3.10 mm; P = 0.01), left ventricular posterior wall thickness (12.5 +/- 2.4 v 11.3 +/- 1.8 mm; P < 0.05), and left ventricle mass index (LVMi; 178 +/- 73 v 155 +/- 61 g/m2; P < 0.01). However, in control patients, these changes were not found after the treatment period. In addition, sequential measurements of neurohormonal mediator levels in patients receiving calcitriol showed that plasma renin (18.5 +/- 12.7 v 12.3 +/- 11.0 pg/mL; P = 0.007), angiotensin II (AT II; 79.7 +/- 48.6 v 47.2 +/- 45.7 pg/mL; P = 0.001), and atrial natriuretic peptide (ANP; 16.6 +/- 9.7 v 12.2 +/- 4.4 pg/mL; P = 0.03) levels significantly decreased, whereas antidiuretic hormone (ADH), epinephrine, and norepinephrine levels did not change significantly. The percent change in LVMi associated with calcitriol therapy had a strong correlation with the percent change in iPTH (r = 0.52; P < 0.05) and AT II (r = 0.47; P < 0.05) levels. We conclude that the partial correction of SHPT with intravenous calcitriol causes a regression in myocardial hypertrophy without biochemical or hemodynamic changes, such as heart rate, BP, and TPR. The changes in plasma levels of iPTH and, secondarily, plasma levels of neurohormones (especially AT II) after calcitriol therapy may have a key role in attenuating ventricular hypertrophy in SHPT.

Advances in indolo[2,3-a]carbazole chemistry: design and synthesis of protein kinase C and topoisomerase I inhibitors

Indolo[2,3-a]carbazoles, their pyrrolo[3,4-c]anellated variants and structurally closely related bisindolylmaleimides represent a biologically highly interesting class of natural compounds which are potential anticancer agents. According to the ongoing literature new and efficient synthetic methods yield a great variety of these compounds which have been reported in detail. The biological activities and the inhibitory activities against the target enzymes protein kinase C and topoisomerase I are also discussed including structure activity relationships. A molecular binding model of the protein kinase C inhibitors with the target enzyme at the atomic level is presented and supported by X-ray crystallographic structures and by molecular modelling studies.

Effects of interleukin-2 transduction on the human hepatoma cell lines using retroviral vector

Gene therapy, using cytokine gene transduction, aims to increase the antigenicity of tumor cells, and to activate the immune effector cells, and thereby inducing tumor regression. With regards to in vitro sensitivity to peripheral blood monocytes and in vivo tumorigenic activity we compared the differences between parent hepatoma cell lines and interleukin-2 (IL-2) transduced hepatoma cell lines using N2A/IL-2 and LNC/IL-2 retrovirus. IL-2 secretion was 186 pg/10(6) cells/24 h in SK-Hep1 cell line and 147 pg/106 cells/24 h in Hep-3B cell line with N2A/IL-2 retroviral vector and was 55,000 pg/10(6) cells/24 h in Hep-3B cell line with LNC/IL-2 retroviral vector. in vitro sensitivity to peripheral blood monocytes was increased by 163.8-254% in IL-2 transduced hepatoma cell lines (Hep-3B/LNC/IL-2, Hep-G2/LNC/IL-2) compared to those of the parent cell lines. The tumor was formed in 1 of 3 BALB/c mice and all 3 nude mice with the injection of 1x107 cells. Simultaneous injection of 1x10(7) cells of the parent cell line (Hep-3B) into the right flank and IL-2 transduced cell line (Hep-3B/LNC/IL-2) into the left flank of the three BALB/c mice and of 5x10(5) cells for the three nude mice resulted in a complete regression of the IL-2 modified tumor cell line (Hep-3B/LNC/IL-2) in 3 weeks and the parent cell line (Hep-3B) in 5 weeks. After injection of 1x10(7) cells into five other nude mice, the tumor of the IL-2 transduced hepatoma cells (Hep-3B/LNC/IL-2) gradually disappeared, however, the tumor of the parent hepatoma cell line initially decreased and then gradually regrew 20 days later. In conclusion, IL-2 transduced hepatoma cell lines secreting IL-2 became more sensitive to peripheral blood monocytes. IL-2 secretion by LNC/IL-2 retrovirus from the hepatoma cell lines was more prominent compared with that by N2A/IL-2 retrovirus. IL-2 transduction into the hepatoma cells resulted in increased antigenicity to the tumors formed by IL-2 transduced hepatoma cell line and parent cell line, which leads the regression of the tumors. However, the higher the tumor burden, the less efficient tumor regression by IL-2 transduction into the hepatoma cell line in nude mice was observed.

Successful treatment with ganciclovir for cytomegalovirus duodenitis following allogenic bone marrow transplantation

Cytomegalovirus(CMV) disease is a major cause of morbidity and mortality in immunocompromised patients. CMV enteritis should be considered when nausea and vomiting continue 3 to 4 weeks after bone marrow transplantation(BMT). The treatment of CMV enteritis is not well established. We report a CMV duodenitis patient following allogenic bone marrow transplantation. The patient had prolonged nausea and vomiting for 5 weeks after bone marrow transplantation and CMV duodenitis was diagnosed by the gastroduodenoscopic mucosal biopsy which showed cytomegalic cells. Ganciclovir treatment for 3 weeks resulted in the resolution of symptoms and promoted healing of the lesion. The patient was free of CMV infection until 288 days after allogenic BMT without maintenance ganciclovir treatment.

Frequent occurrence of transgene deletion in transgenic plants

The status of the transgene in tobacco plants transformed by Agrobacterium was analyzed with PCR. Twelve percent of the transgenic plants with the nptII gene showed different levels of transgene deletion, which was also found in transgenic watermelon (10-30%) and carrot (40-60%). It appeared that the percentage of transgenic plants carrying deleted transgenes depended on both the transgene and the plant. It is suggested that the transgene should be inserted between a right border and a selection marker to reduce the number of transgenic plants containing deleted transgenes after selection.

Isolation and characterization of brain-specific transglutaminases from rat

The relevance of transglutaminases with neural function and several disorders has been emphasized recently. Especially, many polypeptides associated with neurodegenerative diseases are suggested to be putative transglutaminase substrates such as beta amyloid protein of Alzheimer's disease, microtubule-associated proteins and neurofilaments, etc. In addition, the CAG repeated gene products with probable polyglutamine tract, putative transglutaminase substrates, were identified in several neurodegenerative disorders. However, the identity of the brain transglutaminase has not been confirmed, because of enzymic stability and low activity. In the present experiment, we have isolated brain-specific transglutaminases, designated as TGase NI and TGase NII, which are different from other types of transglutaminases in respects of molecular weights (mw. 45 kDa, 29 kDa respectively), substrate affinity, elution profile on ion-exchange chromatography, sensitivity to proteases and ethanol, and immunological properties. The enzymes were localized specifically in the brain tissues but not in the liver tissue. And neural cells such as pheochromocytoma cell, glioma cell, primary neuronal and glial cells were shown to be enriched with TGase NI and TGase NII. The possible biological roles of the enzymes were discussed not only on the aspect of crosslinking activity but also of signal transducing capacity of the enzyme in the brain.

Melatonin increases striatal dopaminergic function in 6-OHDA-lesioned rats

The purpose of this study was to assess the in vivo effects of melatonin, as an antioxidant, on striatal dopaminergic function in rats with a unilateral 6-hydroxydopamine (6-OHDA) lesion of the striatum. Compared with sham-operated controls and expressed as a ratio relative to the contralateral side, there was an increase in the lipid peroxidation product malondialdehyde (MDA, 142%) and a significant reduction in tyrosine hydroxylase (TH) enzyme activity (28%) and dopamine (DA, 32%) and its metabolite dihydroxyphenylacetic acid (DOPAC, 50%) 2 weeks after 6-OHDA injection. Melatonin treatment almost completely restored MDA levels to normal, suggesting the in vivo action of melatonin as an antioxidant. In parallel, partial, but statistically significant recovery of striatal dopaminergic function, including TH enzyme activity and DA levels, also occurred following melatonin treatment. Taken together with our previous reports showing behavioral and histochemical effects of melatonin on the nigrostriatal dopaminergic system, the present results strongly support the hypothesis that melatonin, as an antioxidant, may have beneficial effects on therapeutic approaches for the treatment of oxidative stress-induced neurodegenerative disease such as Parkinson's disease (PD).

Novel carbohydrate specificity of monoclonal antibody 91.9H prepared against human colonic sulfomucin: recognition of sulfo-Lewis(a) structure

Monoclonal antibody (mAb) 91.9H was previously prepared against partially purified human colonic sulfomucins. The epitope was detected in normal colonic mucosa and primary and metastatic colorectal carcinoma in decreasing order of magnitude. In the present study, this antibody was shown to recognize sulfo-Le(a) structure, HSO3-3Gal beta 1-3(Fuc alpha 1-4)GlcNAc. Interactions between mAb 91.9H and synthetic oligosaccharides conjugated with biotinylated polyacrylamide carrier were examined by a biosensor based on surface plasmon resonance and by enzyme-linked immunosorbent assays. This mAb bound to sulfo-Lea but not to sulfo-LeX, Le(a), LeX, sialyl-Le(a), or sialyl-LeX. Sulfo-Le(a) oligosaccharides decreased its binding affinity with mAb 91.9H after periodate oxidation of its fucose residue. Immunohistochemical study showed a strong binding of mAb 91.9H to goblet cells in human colonic epithelia of Lewis-positive individuals but a trace binding in Lewis-negative individuals, confirming the specificity of this antibody toward structures containing a fucosylated type 1 backbone.

Chemical sulfonation and anticoagulant activity of acharan sulfate

Acharan sulfate is a glycosaminoglycan prepared from the giant African snail, Achatina fulica. This polysaccharide has a repeating disaccharide structure of -->4)-2-deoxy-2-acetamido-alpha-D-glucopyranose (1-->4)-2-sulfo-alpha-L-idopyranosyluronic acid (1-->). Its structure is related to heparin and heparan sulfate but is distinctly different from all known members of these classes of glycosaminoglycans. Because of its structural similarities to heparin, chemically modified acharan sulfate was studied to understand the chemical structure effected its anticoagulant activity. After de-N-acetylation, acharan sulfate was N-sulfonated using either chlorosulfonic acid-pyridine or sulfur trioxide-trimethylamine complex. The sulfate level in these products ranged from 22 to 24%(w/w), significantly less than that of heparin at 36%. The molecular weight of both N-sulfoacharan sulfates were comparable with that of heparin. In vitro anticoagulant activity assays showed that N-sulfoacharan sulfate derivatives were moderately active for the inhibition of thrombin and neither product showed any measurable anti-factor Xa activity. The differences in the activities of N-sulfoacharan sulfates produced by these two methods are probably ascribable to a small level of concomitant O-sulfonation obtained when using chlorosulfonic acid-pyridine.

The MUC6 secretory mucin gene is expressed in a wide variety of epithelial tissues

Secretory mucins play an important role in the cytoprotection of epithelial surfaces and are used as tumour markers in a variety of cancers. The MUC6 secretory mucin was originally isolated from a gastric cDNA library. The aim was to determine the specific type and location of MUC6 mucin gene expression in a wide range of human adult and fetal epithelial tissues. In situ hybridization, RNA analysis, and immunohistochemistry were used to quantify and localize mucin gene expression. The data obtained show that MUC6 is highly expressed in gastric mucosa, duodenal Brunner's glands, gall bladder, seminal vesicle, pancreatic centroacinar cells and ducts, and periductal glands of the common bile duct; focal expression is seen in basal endometrial and endocervical glands. MUC6 epitopes were also highly expressed in 7/10 pancreatic cancers and 7/10 cholangiocarcinomas and focally expressed in 4/10 endocervical adenocarcinomas. Expression of MUC6 occurs early in fetal development and was observed in Brunner's glands and pancreatic ducts at 18-19 weeks and in gastric glands at 20 weeks' gestation. The tissue distribution of the MUC6 secretory mucin indicates that it may function to protect epithelial tissues from a wide range of substances. Expression of MUC6 is frequently preserved in pancreatic and bile duct adenocarcinomas, but it is only sparsely expressed in endocervical carcinomas.

Molecular cloning of capillary permeability-increasing enzyme-2 from Agkistrodon caliginosus (Korean viper)

The gene of capillary permeability-increasing enzyme-2 (CPI enzyme-2) was cloned from the cDNA library of Agkistrodon caliginosus and its nucleotide sequence was determined. Its sequence indicates that CPI enzyme-2 is synthesized as a pre-zymogen of 258 amino acid residues, including a putative secretory signal peptide of 18 amino acids and a proposed zymogen peptide of 6 amino acids. The amino terminal sequence deduced from the cDNA sequence was exactly consistent with that of CPI enzyme-2 except for the substitution of an amino acid (Gly27-->Ser). The open reading frame is very similar to those of plasminogen activator and thrombin-like proteases cloned from other snakes. The clone encoding CPI enzyme-2 belongs to the serine protease family. The active site of the enzyme is highly conserved at His41, Asp86 and Ser180. Its possible glycosylation sites, Asn-X-Thr/Ser, are located at amino acid residues 20-22, 55-57, 79-81 and 97-99.

Comparative efficacy of trovafloxacin in experimental endocarditis caused by ciprofloxacin-sensitive, methicillin-resistant Staphylococcus aureus

The new fluoroquinolone trovafloxacin was tested against a ciprofloxacin-sensitive, methicillin-resistant Staphylococcus aureus strain in the rabbit model of endocarditis. Trovafloxacin was more effective than vancomycin (CFU/g of vegetation, 2.65 +/- 1.87 versus 4.54 +/- 2.80 [mean +/- standard deviation]; P < 0.05) or ampicillin-sulbactam plus rifampin (4.9 +/- 1.1 CFU/g). The addition of ampicillin-sulbactam to trovafloxacin tended to reduce titers further.

Immunoglobulin-cytokine fusion molecules: the new generation of immunomodulating agents

Advances in the understanding of genetic engineering, protein expression, and Ig function have come together to allow for the rapid synthesis and production of a novel generation of potent immunomodulating reagents. Selective approaches that allow the isolation of desired specificities will be elucidated through meticulous engineering techniques. This, in turn, may eventually result in the fulfillment of the tremendous potential of engineered proteins for therapeutic and diagnostic applications.

A case of leukemia cutis

We report a case of leukemia cutis with atypical skin manifestations, presented with generalized various sized dark brownish to erythematous patches with plaques on the whole body of a 42-year-old man. Skin lesions developed 6 months ago and had no signs of itching or tenderness. He complained of sustaining fevers with abdominal discomfort. Laboratory findings showed elevation of leukocyte count and peripheral blood smear revealed 86% of lymphocyte. Histologic examination showed diffuse infiltration of abnormal cells that appeared to be leukemic in nature.

Epstein-Barr virus and CD21 expression in gastrointestinal tumors

Epstein-Barr virus (EBV) was found in 7-17% of gastric adenocarcinomas, including lymphoepithelioma-like carcinomas, although its significance has not been clear. In addition, 20-30% of malignant lymphomas arising in the gastrointestinal tract have been known to express the EBV genome. Several lines of evidence indicate that EBV has been shown to infect both B lymphocytes and squamous epithelial cells via CD21 molecule in vivo and in vitro. The expression of CD21 in EBV-associated gastrointestinal tumors, however, has remained controversial. To determine the presence of CD21, an EBV receptor, in the EBV-associated gastrointestinal tumors, we, first, examined the EBV genome in sixty seven patients with either gastrointestinal adenocarcinomas or malignant lymphomas using in situ hybridization (ISH) for EBV-encoded small RNAs (EBERs) and PCR for EBNA-1. Then, the investigation of CD21 expression was performed only in the EBV-positive tumors with immunohistochemical method for CD21 antigen on paraffin sections. EBERs were detected in 6 out of 26 gastric adenocarcinomas, 2 of 24 colonic adenocarcinomas, and 8 of 17 malignant lymphomas. EBERs were more prevalent in the malignant lymphomas originating from the small and large intestine (6/6) than from the stomach (2/11), and were detected in both B and T cell phenotypes. EBNA-1 was amplified in 11 of 16 EBERs-positive cases. Interestingly, however, none of the EBV-positive six gastric adenocarcinomas and eight malignant lymphomas expressed the CD21 on the cell surfaces or cytoplasm of both tumor cells and adjacent normal epithelial cells. These results suggest that EBV infection in the gastrointestinal malignancies would be mediated via different routes besides the CD21 or a new receptor distinct from CD21.

Isolation of a novel auxin receptor from soluble fractions of rice (Oryza sativa L.) shoots

An auxin binding protein (ABP) was isolated from the shoots of rice seedlings and characterized. The ABP was found to be a monomer with a molecular mass of 57 kDa and play a crucial role via auxin binding in regulating H+ translocation activity of the plasma membrane in a typical biphasic manner. The results of binding equilibrium experiments indicate that the ABP binds indole 3-acetic acid with a high affinity (Kd = 1.9 x 10(-8) M), having four primary binding sites for auxin and some secondary sites with low auxin affinities. The ABP appears to have an unambiguous auxin receptor function.

Colonoscopic diagnosis of whipworm infection

Trichuriasis is an intestinal infection found in human beings which is caused by Trichuris trichiura, more commonly known as whipworm because of its whip-like appearance. It is characterized by the invasion of the colonic mucosa by the adult Trichuris and produces minor inflammatory changes at the sites of localization. It is prevalent throughout the world, especially in tropical areas. Its diagnosis is usually made by identification of the typical eggs in the stool; adult whipworm is rarely seen during colonoscopy. Colonoscopy can directly diagnose trichuriasis, confirming the threadlike form of worms with an attenuated end. The worms can be overlooked, particularly if colon preparation is imperfect. Attenuated whip-like ends of whipworms, which are embedded in the colonic mucosa, were removed with biopsy forceps. We report on 5 cases of whipworm infection that were diagnosed on total colonoscopy.

Evidence that a beta-1,4-endoglucanase secreted by Acetobacter xylinum plays an essential role for the formation of cellulose fiber

Cellulose-producing Acetobacter xylinum has been known to secrete a cellulose-hydrolyzing beta-1,4-endoglucanase (CMCax). When antibodies to recombinant CMCax were added to the culture medium, the formation of cellulose fiber was severely inhibited. Western blot analysis using the antibody showed that this enzyme was secreted into the medium even by a cellulose non-producing strain (Cel-). These results indicate that beta-1,4-endoglucanase in the medium plays a critical role in the formation of cellulose fiber by the microorganism.