Effects of formaldehyde vapor on the nasal cavity and lungs of F-344 rats

Histopathological and biochemical examinations of the nasal cavity and lungs of rats inhaling 145.6 ppm (high-dose) or 15.0 ppm (low-dose) formaldehyde vapor for 6 h revealed dose-related damage. The contents of non-protein SH groups (NPSH) in the nasal mucosa and lung, and lipid peroxide (LPO) in the nasal mucosa were decreased, whereas LPO was increased in the lung. The contents of triglyceride in the lung tissue and lavage, and free cholesterol in the lung were decreased, providing evidence of a suppression of surfactant production. Exposure-related changes in the nasal turbinates, trachea, and lung included hyperkeratosis of the squamous epithelium, increased secretion, and desquamation of ciliated and mucosal cells. Under the present experimental conditions, 145.6 ppm formaldehyde vapor was found to strongly affect the exposed tissues. Changes in lipid peroxide were dependent on the level of exposure.

Divergent effects of endoscopic sphincterotomy on the long-term outcome of hepatolithiasis

BACKGROUND

The long-term value of endoscopic sphincterotomy in patients with hepatolithiasis has not been established.

METHODS

Long-term clinical effects of endoscopic sphincterotomy on hepatolithiasis were determined in 57 patients. All patients had sphincterotomy to remove their common bile duct stones. Intrahepatic stones were removed completely in 21 patients, while the stones partly remained in 36 patients despite combined use of surgery and/or percutaneous trans-hepatic choledochoscopy. Three patients of the latter group spontaneously passed all the remaining stones soon after the sphincterotomy.

RESULTS

Follow-up at 66 to 183 months (mean, 114 months) was available in 54 patients (94.7%). Late complications occurred in 10 patients with the remaining stones, including seven cases of cholangitis (two fatalities) and three of liver abscess (one fatality). In contrast, those with complete clearance developed no complications.

CONCLUSIONS

Endoscopic sphincterotomy has divergent effects on the long-term outcome of patients with hepatolithiasis. Every effort should be made to remove the intrahepatic stones as completely as possible shortly after sphincterotomy if the patient is to be managed endoscopically and adverse effects are to be avoided.

[The Human Menopausal Gonadotrophin Reference Standard (Control 961) of the National Institute of Health Sciences]

Raw human menopausal gonadotrophin (HMG) material was examined for preparation of the "Human Menopausal Gonadotrophin Reference Standard (Control 961)". The candidate material was assayed its follicle stimulating hormone (FSH) activity and luteinizing hormone (LH) activity against the 3rd International Standard for FSH and LH, urinary (71/264) by the augmented ovarian weight gain assay and the seminal vesicle weight gain test, respectively. The potency of the new standard was defined as 56 international units of FSH activity per mg and 61 international units of LH activity per mg as the result of 13 and 5 assays, respectively, in four collaborative laboratories.

Comparative developmental toxicity of di-, tri- and tetrabutyltin compounds after administration during late organogenesis in rats

Dibutyltin dichloride (DBT), tributyltin chloride (TrBT) and tetrabutyltin (TeBT) were compared for their developmental toxicity and teratogenic potential following administration during the susceptible period for teratogenesis of TrBT. Pregnant rats were given either DBT or TrBT at a dose of 165 or 330 mumol kg-1 or TrBT at a dose of 330, 660, 1320, 2640 or 5280 mumol kg-1 on days 13-15 of pregnancy. Treatment with DBT at 165 and 330 mumol kg-1 caused a significant decrease in the maternal body weight gain. A significant decrease in the fetal weight occurred at 165 and 330 mumol kg-1. No significantly increased incidences of postimplantation loss or of fetuses with malformations were found following treatment with DBT. Treatment with TrBT at 165 and 330 mumol kg-1 resulted in a significant decrease in the maternal weight gain. A significant decrease in the fetal weight was found at 330 mumol kg-1. A significantly and markedly increased incidence of fetuses with cleft palate was noted in both groups treated with TrBT. Treatment with TeBT caused a significantly decreased maternal body weight gain at doses of 660 mumol kg-1 and above. A significantly increased incidence of fetuses with cleft palate was observed at a dose of 5280 mumol kg-1. It could be concluded that there is a difference in the manifestation and degree of developmental toxicity between DBT, TrBT and TeBT.

Characteristics of growth, morphology, contractility, and protein expression of fibroblasts derived from keloid

Phenotypic alterations of keloid-derived fibroblasts were characterized by comparison with the phenotypes of normal fibroblasts from the same patient. Explant cultures of keloids showed unique features. Keloid explants contracted considerably and reduced their size during culture, whereas the size of normal skin explants remained unchanged. Enlarged cells were found among fibroblasts which had grown out of all the explants and were morphologically distinct from fibroblasts; however, keloid explants produced many more of them than did the normal tissues. The growth rate of fibroblast colonies formed from normal explants was five times higher than keloid explants. Keloid fibroblasts which had been serially cultivated contracted lattices of collagen gels at a rate similar to normal fibroblasts. Proteins extracted from serially cultivated fibroblasts were mapped on polyacrylamide two-dimensional electrophoretic gels. No significant qualitative alterations in protein expression in keloid cells were found as compared with normal fibroblasts. However, some quantitative changes were found between the two. A computer-assisted image analyzer detected 151 polypeptide spots--50 spots (33%) of which increased their amounts in keloid cells, whereas 34 spots (22.5%) decreased in comparison with normal fibroblasts. Sixteen major polypeptides were identified as known proteins with the aid of time-of-flight mass spectrometry. The level of expression of these identified proteins was similar between normal and keloid cells, except stathmin whose expression was suppressed in keloid fibroblasts.

Exact documentation of location and size of bladder tumor with a three-dimensional mapping device

BACKGROUND

Cystoscopy is one of the most important devices for diagnosing bladder tumor, but has a crucial shortcoming--the size of observed objects cannot be measured. This paper describes a new method to measure the position and size of a bladder tumor using a three-dimensional mapping device.

METHODS

The three-dimensional mapping device, which is connected to an endoscope prior to use, can precisely measure the size and show the position of a bladder tumor. It consists of several arms connected by an angle sensor mounted on the articular site. One end of the device is fixed to the table and the other end is connected to the eye piece of an endoscope. Weight balancers keep each arm in a well balanced position, so urologists can freely manipulate the endoscope. Data from the angle sensor is sent to a personal computer (PC), which computes data such as three-dimensional coordination and diameter of a tumor. The diameter of a tumor is calculated by the PC according to the Pythagorean theorem.

CONCLUSION

The position and size of a bladder tumor can be measured using our three-dimensional mapping device.

A cross-sectional study on nerve conduction velocities among workers exposed to carbon disulphide

We examined nerve conduction velocities (NCVs) in the ulnar nerve (motor, slower motor fiber and mixed), the peroneal nerve (motor, MCV) and the sural nerve (sensory, SCV) among 46 Japanese workers exposed to carbon disulphide (CS2, CS2-exposed group) and 28 normal control workers (group C). The subjects had not suffered from diseases or injuries of the peripheral or central nervous system. MCV in the peroneal nerve and SCV in the sural sural nerve in the CS2-exposed group were significantly reduced compared with those of group C (p < 0.05 in both), but no significant difference in NCVs of the ulnar nerve was noted between the two groups. In the two subgroups of the CS2 exposed group (currently exposed: group E n = 24; removed from exposure: group R n = 22), NCVs of group E tended to be lower than those of group R in spite of the younger age of group E. MCV in the peroneal nerve and SCV in the sural nerve in group E were significantly reduced compared with those in group C, but not significantly in group R. These findings indicate the existence of a toxic effect of CS2 exposure on the NCV, predominantly evident in the lower limbs in those workers. On removal from CS2 exposure, NCV recovery seemed to be possible.

Synthesis of the methyl alpha-glycoside of a trisaccharide mimicking the terminus of the O antigen of Vibrio cholerae O:1, serotype Inaba

Coupling of methyl 4-amino-4,6-dideoxy-2-O-4-methoxybenzyl-alpha-D-mannopyranoside, obtained from the corresponding 4-azido derivative by treatment with H2S, with 3-deoxy-L-glycero-tetronolactone gave the crystalline methyl 4-(3-deoxy-L-glycero-tetronamido)-4,6-dideoxy-2-O-4-methoxybenzyl- alpha-D- mannopyranoside (7). Subsequent acetylation of 7, followed by O-demethoxybenzylation of the 8 formed gave the crystalline methyl 3-O-acetyl-4,6-dideoxy-4-(2,4-di-O-acetyl-3-deoxy-L-glycero-tetronami do)-alpha- D-mannopyranoside (9), which was used as the key intermediate in the construction of the title trisaccharide. To make a glycosyl donor allowing the extension of the oligosaccharide chain at O-2, compound 9 was converted, via conventional transformations, into 3-O-acetyl-2-O-bromoacetyl-4,6-dideoxy-4-(2,4-di-O-acetyl-3-deoxy-L-glyc ero- tetronamido)-alpha-D-mannopyranosyl chloride (12). Condensation of 12 with 9 afforded the disaccharide 20 having a selectively removable protecting group at O-2(2). The latter was O-debromoacetylated, and the disaccharide nucleophile thus obtained was treated with 2,3-di-O-acetyl-4,6-dideoxy-4-(2,4-di-O-acetyl-3-deoxy-L-glycero-tetr onamido)- alpha-D-mannopyranosyl chloride to give, after O-deacetylation, the target, title trisaccharide. The constituent monosaccharide of the O-specific polysaccharide antigen of Vibrio cholerae serotype Inaba, 4-(3-deoxy-L-glycero-tetronamido)-4,6-dideoxy-D-mannopyranose (18), was obtained from the peracetate of its methyl alpha-glycoside by acetolysis, followed by O-deacetylation. The amorphous compound 18 was characterized by 1H and 13C NMR spectroscopy and through its crystalline alpha-per-O-acetyl derivative.

Altered gene expression of natriuretic peptide receptor subtypes in the kidney of stroke-prone spontaneously hypertensive rats

1. To elucidate the physiological and pathophysiological role of the natriuretic peptide system in the progression of hypertensive renal disease, we examined the gene expression of natriuretic peptide receptor subtypes, guanylate cyclase-A (GC-A), guanylate cyclase-B (GC-B) and clearance receptor (C receptor), in the kidney of stroke-prone spontaneously hypertensive rats (SHRSP) at 8 and 20 weeks of age, and compared them with their gene expression in age-matched Wistar-Kyoto (WKY) rats. 2. Northern blot analyses revealed that messages for three natriuretic peptide receptor subtypes were expressed in the kidney, and their expressions were higher in the glomeruli than in the whole kidney in each strain. 3. In 20 week old rats with established hypertension, the glomerular concentration of GC-A mRNA was significantly higher in SHRSP than in WKY. The concentrations of GC-B and C receptor mRNA in the glomeruli tended to increase and decrease, respectively, but they were not statistically significant in SHRSP. 4. In 8 week old rats, the glomerular concentrations of GC-A, GC-B and C receptor mRNA were not significantly different between SHRSP and WKY. 5. This study demonstrates that in the progression of hypertension, the expression of GC-A, which mediates biological actions of natriuretic peptides, is enhanced in the kidney of SHRSP compared to that of WKY. Together with the augmented secretion of the ligands previously revealed, altered expression of natriuretic peptide receptor subtypes in SHRSP may have a deterrent role in the development of hypertension and its renal complications.

Preparation of a monoclonal antibody against mouse brain natriuretic peptide (BNP) and tissue distribution of BNP in mice

1. In order to explore the significance of brain natriuretic peptide (BNP), a cardiac hormone secreted from the ventricle, in mice, we prepared a monoclonal antibody against mouse BNP (mBNP) and established a specific radioimmunoassay (RIA) for mBNP. 2. A monoclonal antibody, KY-mBNP-I, was prepared by the fusion of mouse myeloma cells X63-Ag8.653 with spleen cells of the BALB/c mouse immunized with synthetic mBNP[108-121] conjugated to bovine thyroglobulin. KY-mBNP-I belonged to an IgG2a subclass and showed a high affinity for mBNP (Ka = 1.8 x 10(11) mol/L-1). 3. The RIA established that using KY-mBNP-I was highly sensitive and specific for mBNP, with an IC50 value of 3 fmol/tube and cross-reactivities of less than 0.003% with related natriuretic peptides. mBNP-like immunoreactivity (mBNP-LI) was detected in the mouse atrium (0.35 +/- 0.02 nmol/g), ventricle (20.5 +/- 0.5 pmol/g) and kidney (0.50 +/- 0.05 pmol/g), but not in other tissues including brain. 4. Gel filtration analysis revealed that the major component of tissue mBNP-LI was co-eluted with synthetic mBNP[77-121], a 45-amino acid mature peptide. 5. The monoclonal antibody and RIA for mBNP established here will provide useful tools to investigate the functional significance of BNP in mice, coupled with the genetic engineering approach.

Augmented expression of the endothelin-A receptor gene in cultured mesangial cells from stroke-prone spontaneously hypertensive rats

1. To elucidate the role of endothelin (ET) receptor in hypertension, we studied the expression of the ET-A receptor (ET-AR) gene and the ET-B receptor (ET-BR) gene in cultured mesangial cells isolated from stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto (WKY) rats. 2. The mesangial cells from both SHRSP and WKY expressed ET-AR predominantly. The level of the ET-AR mRNA in mesangial cells from SHRSP was 5-fold higher than that in the cells from WKY. The ET-BR mRNA in the mesangial cells from both strains was hardly detectable by northern blot analysis. 3. These results demonstrate that the expression of the ET-AR gene was markedly augmented in mesangial cells from SHRSP.

Decreased expression of the very low density lipoprotein receptor mRNA in the cardiac ventricle of spontaneously hypertensive rats

1. To elucidate the functional implication of very low density lipoprotein (VLDL) receptor, we studied the gene expression of VLDL receptor in rats. The VLDL receptor mRNA was highly expressed in the cardiac ventricle and skeletal muscle. Intermediate amounts of VLDL receptor mRNA were detected in adipose tissue, adrenal gland, brain and lung. Thus the tissue distribution of VLDL receptor mRNA in rats was similar to that reported previously in rabbits. 2. We studied the gene expression of the VLDL receptor in the heart of stroke-prone spontaneously hypertensive rats (SHRSP), an animal model for hypertension-induced cardiac hypertrophy. RNase protection assay showed that the level of ventricular VLDL receptor mRNA was already decreased to one half when hypertension was not fully developed, and further diminished to one fifth when cardiac hypertrophy was established. 3. It is reported that energy utilization in SHRSP hypertrophied myocardium is impaired. Our results suggest that inactive fatty acid metabolism in the ventricle of SHRSP is related to the lowered expression of the VLDL receptor which is postulated as a gate for triglyceride-rich lipoprotein particle.

Structural organization and chromosomal assignment of the human obese gene

The obese (ob) gene has been identified through a positional cloning approach; the mutation of this gene causes marked hereditary obesity and diabetes mellitus in mice. We report here the isolation and characterization of the human ob gene. Southern blot analysis demonstrated a single copy of the ob gene in the human genome. The human ob gene spanned approximately 20 kilobases (kb) and contained three exons separated by two introns. The first intron, approximately 10.6 kb in size, occurred in the 5'-untranslated region, 29 base pair (bp) upstream of the ATG start codon. The second intron of 2.3 kb in size was located at glutamine +49. By rapid amplification of 5'-cDNA ends, the transcription initiation sites were mapped 54-57 bp upstream of the ATG start codon. The 172-bp 5'-flanking region of the human ob gene contained a TATA box-like sequence and several cis-acting regulatory elements (three copies of GC boxes, an AP-2-binding site, and a CCAAT/enhancer-binding protein-binding site). By the fluorescence in situ hybridization technique, the ob gene was assigned to human chromosome 7q31.3. This study should establish the genetic basis for ob gene research in humans, thereby leading to the better understanding of the molecular mechanisms underlying the ob gene.

Augmented expression of the obese gene in the adipose tissue from rats fed high-fat diet

Expression of the obese (ob) gene is augmented in the adipose tissue in several rodent models of genetic obesity. In the present study, we examined the ob gene expression in a rodent model of acquired obesity obtained by pure overfeeding of normal rats. Male Sprague-Dawley rats at 8 weeks of age were fed standard diet or high-fat diet. Rats fed high-fat diet developed moderate degree of obesity, hyperglycemia, and hyperlipidemia as compared with rats fed standard diet. Northern blot analysis revealed that the ob gene is expressed abundantly in the adipose tissue obtained from the epididymal, mesenteric, subcutaneous, retroperitoneal, and interscapular fat pads in rats fed standard diet. Expression of the ob gene was augmented in all the adipose tissue examined in rats fed high-fat diet. The present study demonstrates that the ob gene expression is augmented in the adipose tissue in diet-induced obesity, thereby suggesting the pathophysiologic roles of the ob gene in acquired obesity.

Molecular cloning and expression of multiple isoforms of human prostaglandin E receptor EP3 subtype generated by alternative messenger RNA splicing: multiple second messenger systems and tissue-specific distributions

Five distinct cDNA clones encoding four different isoforms of human prostaglandin (PG) E receptor EP3 subtype were isolated from a human kidney cDNA library. Two cDNA clones differed only in their 3'-untranslated regions. The four isoforms, tentatively named EP3-I, EP3-II, EP3-III, and EP3-IV, which were generated by alternative mRNA splicing, had identical amino acid sequences except for their different carboxyl-terminal tails. Transfection experiments revealed that all the four isoforms show high binding affinities to PGE2, PGE1, and M&B28767, an EP3-specific agonist, whereas their downstream signaling pathways are divergent. M&B28767 increased cAMP concentrations in cells expressing EP3-II and EP3-IV, whereas it inhibited forskolin-induced cAMP accumulations in cells expressing all EP3 isoforms. M&B28767 also stimulated phosphoinositide turnover in cells expressing EP3-I and EP3-II. Northern blot analysis revealed that the EP3 gene is expressed in a wide variety of human tissues. The human EP3 mRNA was present most abundantly in the kidney, pancreas, and uterus. A substantial expression was also detected in the heart, liver, skeletal muscle, small intestine, colon, prostate, ovary, and testis. Furthermore, reverse transcription-polymerase chain reaction analysis demonstrated tissue-specific expressions of the five different EP3 mRNA species. The present study suggests the presence of the multiple systems of PGE2/EP3 isoforms and leads to the better understanding of its physiological and pathophysiological implications in humans.

Comparative study of bone marrow induced by purified BMP and recombinant human BMP-2

Into a calf muscle pouch in Wistar rats, 50 micrograms purified bone morphogenetic protein (pBMP) or 50 micrograms recombinant human bone morphogenetic protein-2 (rhBMP-2) was implanted using atelopeptide type I collagen solution (CL) as a carrier. Three weeks later bone and bone marrow were induced in both groups. These induced bone and bone marrow were studied histologically. In the pBMP+CL group (n = 5), rich bone matrix and little bone marrow were observed. There was no fatty marrow or angioid tissue observed. In the rhBMP-2+CL group (n = 5), bone matrix and rich marrow including fatty marrow and angioid tissue were observed around and among the bony trabeculae. It was suggested that a "self-supporting bone organ" was induced.

[Clinical aspects and types of Sjögren's syndrome]

Sjögren's syndrome (SS) is a systemic as well as an organ-specific autoimmune disease, characterized by destructive lymphocytic infiltration of the salivary and lacrimal glands. We divided SS patients into three stages: stage I is glandular SS, stage II is extraglandular SS, and stage III is extraglandular SS with lymphoid malignancy. The lymphoaggressive nature of the disease appears to lead SS patients from stage I to II and from stage II to III. However, stage III patients made up only 5% of SS patients. Many patients remain stable in stages I or II for as long as 10 or 20 years. Therefore, we can assume that there are factors which trigger patients in stages I or II to progress to stages II or III and that only those patients who have such factors progress from stages I or II to stages II or III, respectively. Accumulation in the salivary glands or in the peripheral blood of B cells which have rearrangement of the RF-related germline gene Vg or over-expression of the bcl-2 gene in the lymphoepithelial lesion might be included among these factors.

[Lymphoproliferative disorders in patients with Sjögren's syndrome--Vg gene rearrangement and expression of bcl-2 protein]

Sjögren's syndrome (SS) is a unique disease which develops a high incidence of lymphoproliferative disorders (LPD) such as monoclonal gammopathy or malignant lymphoma. In order to elucidate the mechanism responsible for the emergence of monoclonal B cell proliferation at the site of a chronic autoimmune reaction, the rheumatoid factor (RF) related germline gene Vg and expression of the bcl-2 gene in the lymphoepithelial lesion (LEL) were studied. Predominant usage of the Vg or Vg-like genes was found in the peripheral blood leukocytes in SS patients and abundant expression of bcl-2 protein in the lymphocytes in and around the LEL were observed. These results suggest that RF clones were activated resulting into monoclonal proliferation and overexpression of bcl-2 protein play a role allowing the cell to escape a apoptotic cell death resulting into the increased risk of monoclonal proliferation in SS patients.

Differential response to transforming growth factors-beta1 and beta2: connective tissue deposition in animal models

The ability of transforming growth factor (TGF)-beta(1) and TGF-beta(2) to promote connective tissue deposition were compared in different animal models. A single subcutaneous injection of TGF-beta(2) in collagen/heparin gel carrier promoted markedly more extensive development of connective tissue than TGF-beta(1) at the site of injection in both neonatal and adult mice. Both TGF-beta(1) and TGF-beta(2) promoted deposition of dense and well-vascularized connective tissue matrix infiltrated with macrophages and fibroblasts. However, the results of immunohistochemical analyses suggested that TGF-beta(2) promoted an accumulation of more macrophages in the connective tissue than TGF-beta(1). Similar differences in the extent of connective tissue development were observed in neonatal mice when these factors were administered as a solution, without the collagen/heparin gel carrier. TGF-beta(2) was also more potent than TGF-beta(1) in domestic pigs. However, in guinea pigs, TGF-beta(1) promoted more extensive connective tissue development than TGF-beta(2). These results suggest that the differential connective tissue response to TGF-beta(1) and TGF-beta(2) is species dependent. However, the differences in the physical and chemical properties of these factors may account in part for the differential response as well.

Rapid ventricular induction of brain natriuretic peptide gene expression in experimental acute myocardial infarction

BACKGROUND

We have demonstrated that brain natriuretic peptide (BNP) is a cardiac hormone predominantly synthesized in and secreted from the ventricle. We have also reported that, compared with atrial natriuretic peptide (ANP), the plasma concentration of BNP is increased to a greater degree in patients with congestive heart failure and more rapidly in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

To investigate ventricular gene expression of BNP in AMI, we analyzed plasma and ventricular BNP concentrations along with ventricular BNP mRNA in rats with AMI produced by coronary artery ligation. The BNP concentration in the left ventricle increased about 2-fold as early as 12 hours postinfarction and 5-fold 1 day postinfarction compared with sham-operated rats, whereas left ventricular ANP concentration remained unchanged within 1 day. The tissue concentration of BNP increased in the noninfarcted region as well as in the infarcted region. The surviving myocytes in and around the necrotic tissues in the infarcted region were intensely stained with the anti-BNP antiserum, indicating augmented production in the remaining myocytes in the infarcts. The BNP concentration in the right ventricle also increased about 10-fold 12 hours postinfarction, whereas the ANP concentration remained unchanged within 12 hours. Northern blot analysis revealed that BNP mRNA expression was augmented 3-fold in the left ventricle as early as 4 hours postinfarction. In contrast, ANP mRNA expression was unchanged. Reflecting the rapid induction of ventricular BNP production, the plasma BNP concentration rose to about 100 pg/mL 12 hours postinfarction (sham-operated rats, < 70 pg/mL).

CONCLUSIONS

These results demonstrate the rapid induction of ventricular BNP gene expression in rats with AMI compared with ANP and suggest that BNP gene expression in the ventricle is regulated distinctively from ANP gene expression against acute ventricular overload. They also suggest that the BNP gene can be one of the acutely responsive cardiac genes for the ventricular overload and suggest a possible pathophysiological role of BNP distinct from ANP in AMI.

Synthesis and crystal structure of methyl 4-6-dideoxy-4-(3-deoxy-L- glycero-tetronamido)-2-O-methyl-alpha-D-mannopyranoside, the methyl alpha-glycoside of the terminal unit, and presumed antigenic determinant, of the O-specific polysaccharide of Vibrio cholerae O:1, serotype Ogawa

Methyl 4-azido-4,6-dideoxy-3-O-benzyl-alpha-D-mannopyranoside and its analogous 3-O-(4-methoxybenzyl) derivative were methylated and the 2-O-methyl derivatives formed were converted into methyl 4-amino-4,6-dideoxy-2-O-methyl-alpha-D- mannopyranoside [sequence: see text]. Reaction of the latter with 3-deoxy-L-glycero-tetronolactone gave the methyl glycoside of 4,6-dideoxy-4-(3-deoxy-L-glycero- tetronamido)-2-methyl-alpha-D-mannopyranose [sequence: see text], the monosaccharide that is reported to be the terminal moiety of the O-specific polysaccharide of Vibrio cholerae O:1, serotype Ogawa. The unit cell packing of the compound, which crystallized as a monohydrate, differs from that of the previously described crystalline compound lacking the 2-O-methyl group. The unmethylated sugar is the terminal moiety of the O-specific polysaccharide of Vibrio cholerae O:1, serotype Inaba. The crystal structure of methyl 4,6-dideoxy-2-O- methyl-4-trifluoroacetamido-alpha-D-mannopyranoside [sequence: see text] is also described.

Different expression of esterase variants in rat hepatic and hepatoma-derived cell lines detected by electrophoresis

Esterases in nine rat hepatic and hepatoma-derived cell lines and normal rat liver homogenate were detected by polyacrylamide gel electrophoresis coupled with active staining with alpha-naphthyl acetate or butyrate as a substrate. The esterase band patterns of the non-cancerous and oncogene-transformed cell lines were alike, but different from those of hepatoma cell lines and normal rat liver homogenate. The former groups of cells might have completely lost the characteristics of rat liver parenchymal cells, or else they might have their origin at cells other than liver parenchyma. The esterase patterns of the hepatoma cell lines (e.g., McA-RH7777) and the normal rat liver highly resembled with each other, exemplifying the slight biochemical deviation of cancer from normal cells. However, two-dimensional electrophoretogram for the McA-RH7777 cell line showed a prominent esterase spot (pI 6.0-M(r) 110 kDa) that was lacking in the normal liver. This result indicates that there is invariably some change in esterase expression between the cancer cells and the normal liver cells.