Cerebral blood volume in the sleep measured by near-infrared spectroscopy

We investigated the relationship between hemodynamic changes in the cortex measured by near-infrared spectroscopy (NIRS) and the polysomnographic changes during sleep. Four healthy male volunteers participated in the study. Near-infrared spectroscopy measuring and polysomnographic recordings were done simultaneously during sleep. In many case, oxy-hemoglobin (oxy-Hb) decreased and deoxy-hemoglobin (deoxy-Hb) increased during the transition from wakefulness to sleep, and oxy-Hb increased toward deep sleep. Oxy-Hb and deoxy-Hb had larger fluctuations during REM sleep than those during non-REM sleep. During REM sleep, oxy-Hb often showed a lower level and deoxy-Hb showed a higher level than those during the preceding and following non-REM sleep.

Small bowel rejection in isolated small bowel transplantation and in multivisceral transplantation: a comparative study in a large animal model

The proposition that a combined graft including the liver protects other organ allografts from the same donor is well known. However, it is not evident in the clinical results. The present experiments were undertaken to compare acute small bowel rejection in isolated small bowel transplantation with multivisceral transplantation. Using 36 outbred, male Large-White pigs, isolated small bowel transplantation (SBTX: n = 9) and abdominal multivisceral transplantation (MVTX: n = 9) were performed without immunosuppression. The survival rate and blood serum samples were monitored postoperatively. In order to compare acute small bowel rejection, sequential biopsy specimens from Thiry-Vella loops were also monitored daily beginning on me 3rd day after transplantation. The specimens were scored from 0 to 3 according to the severity of the rejection. The survival rate was not significantly different. However, significant differences were noted in the cause of the death and in the pathologic changes of the small bowel. In contrast to SBTX, the small bowel rejection of MVTX was significantly delayed and less severe. The rejection score of MVTX was significantly better than SBTX from 5 postoperative days (POD) to 1 lPOD (P < 0.05). The present study demonstrated mat acute small bowel rejection of MVTX graft including the liver was delayed and less severe than that of SBTX in an outbred large animal model.

Influence of the flow rate during flushing on porcine multivisceral preservation

The effect of flushing flow rate during multiple organ procurement (MOP) on viability of the liver, pancreas, and intestine were investigated in porcine multivisceral transplantation. Splanchnic organs were flushed in situ with 50 ml/kg of 4 degrees C UW solution via the aorta using a pump at a flow rate of 10, 30, or 50 ml/kg/min. After storage and transplantation, we assessed the clearance of hyaluronic acid (CHA) for hepatic endothelial cells function, liver enzymes, amylase, and histology. Two-day survival was 17% in the 10 ml/kg/min group and 67% in other groups. The former group had inadequate flushing out of the hepatic and intestinal grafts, resulting in aggravation of CHA and intestinal tissue injury. At the flow rate of 30 ml/kg/min, the viability and integrity of all organs were well maintained. We conclude that the optimal flushing flow rate would differ for each organ, therefore the common flow rate acceptable for any of the individual grafts should be applied in MOP.

Mucin secretion in inflammatory bowel disease: comparison of a macrophage-derived mucin secretagogue (MMS-68) to conventional secretagogues

We have described a novel macrophage-derived mucin secretagogue (MMS-68) that mediates mucin secretion in colon cancer cell lines and explants of normal and inflammatory bowel disease (IBD) mucosa. We compared MMS-68 induced mucin release with other known intestinal mucin secretagogues in normal colon explants and in the HT-29 colon cancer cell line, and to study the effects of MMS-68 on mucin release from inflamed and uninflamed ulcerative colitis (UC) and Crohn's disease (CD) mucosa. In normal colonic explants and HT-29 cells, each of the secretagogues including, MMS-68-induced mucin release two- to fivefold more than culture medium alone. In HT-29 cells, MMS-68 plus leukotriene C4 (LTC4) induced a 50% increase in mucin release over either secretagogue alone, and MMS-68 plus platelet-activating factor (PAF) markedly enhanced mucin release by eightfold over either secretagogue. In colonic explants from patients with UC and CD, the mucin release in response to MMS-68 was similar to that of normal colonic explants. Likewise, in isolated epithelial cells from CD and UC (whether involved or uninvolved), MMS-68-induced release was similar to that of epithelial cells isolated from normal colonic mucosa. The number of MMS-68-producing macrophages was lower in uninflamed UC mucosa compared with inflamed UC mucosa and CD mucosa. The mucin secretagogue activity of MMS-68 is comparable to that of other known secretagogues, and PAF can have a synergistic effect on this activity. Whole tissue explants and isolated colonic epithelial cells from patients with IBD respond at least as well as their normal counterparts to MMS-68. MMS-68 may play a role in mucin secretion in normal and inflamed colonic tissue.

Different modes of sialyl-Tn expression during malignant transformation of human colonic mucosa

Monoclonal antibodies TKH2 and B72.3, which react with the mucin-associated sialyl-Tn(STn) antigen, preferentially bind to cancerous but not normal colonic tissues. If O-acetyl groups are removed by saponification of tissues, MAb TKH2 will react with normal colonocytes, whereas MAb B72.3 remains non-reactive. To explain this difference in binding specificity, we tested both MAbs against synthetic constructs of single (monomeric) or clustered (trimeric) STn epitopes by enzyme immunoassay. Both MAb TKH2 and MAb B72.3 reacted with trimeric STn, but MAb TKH2 demonstrated greater binding than MAb B72.3 to monomeric STn. This suggests that normal colonic mucosa expresses monomeric STn epitopes, but that with transformation to malignancy, clustered STn epitopes appear. The appearance of clustered STn epitopes during colonic carcinogenesis represents a novel pattern of carbohydrate antigen expression and implicates alterations at the level of apomucins and/or glycosyltransferases responsible for cluster epitope formation.

The effects of niacin on DNA repair after N-methyl-N'-nitro-N-nitrosoguanidine treatment in normal human lymphocytes

We have investigated the effects of niacin on NAD levels and on DNA repair in human lymphocytes. When lymphocytes were incubated in culture medium with various concentrations of niacin, incubation of lymphocytes with nicotinic acid at 5 microM or nicotinamide at 10 mM caused a 2-3 fold increase in NAD content. Under these conditions lymphocytes were treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Interestingly, the rejoining of DNA strand breaks was promoted by nicotinic acid but nicotinamide inhibited the rejoining.

Absence of measles virus receptor (CD46) in lesions of subacute sclerosing panencephalitis brains

In this study we investigated pathological changes of the expression of the measles virus (MV) receptor, CD46, in subacute sclerosing panencephalitis (SSPE) brains. We analyzed CD46 expression in lesions of brain specimens from five SSPE patients in comparison to uninfected regions of the same brains and to normal human brains. The correlation between CD46 and MV infection, in individual cells in SSPE brains, was analyzed by double-staining procedures using monoclonal antibodies (mAbs) and in situ hybridization to detect MV-specific mRNAs. We found that CD46 was expressed at relatively low levels by neurons and astrocytes in normal brains in comparison to neuroblastoma and astrocytoma cell lines. Within heavily infected (MV-positive) brain lesions of all five SSPE cases, CD46 was either not detected or was expressed to a lesser degree by neural cells, irrespective of whether MV antigens were detectable or not. In contrast, normal levels of CD46 were found in SSPE brain tissue distant from the lesion. Using in situ hybridization, mRNAs of both MV nucleocapsid and MV hemagglutinin (MV-H) were detected in all SSPE lesions, while no or only small amounts of MV-H protein were detected. MV-infected neurons were never found to express CD46. Although a strict correlation between levels of the MV-H protein and the absence CD46 could not be seen, these findings suggest that the CD46 expression is reduced by the MV infection in lesions of SSPE brains.

Myeloperoxidase-antineutrophil cytoplasmic antibody-associated glomerulonephritis with membranous nephropathy in remission

A 47-year-old woman developed pulmonary hemorrhage and an increase in proteinuria during remission of membranous nephropathy. Renal biopsy revealed crescentic glomerulonephritis. She also had a high perinuclear antineutrophil cytoplasmic antibody level, so a diagnosis of myeloperoxidase-antineutrophil cytoplasmic antibody-associated glomerulonephritis was made. After immunosuppressive therapy was started, the pulmonary hemorrhage resolved and her proteinuria decreased. Renal biopsy was repeated after treatment and showed histological improvement. This case suggests that there may be a relationship between membranous nephropathy and myeloperoxidase-antineutrophil cytoplasmic antibody-associated glomerulonephritis.

Portal-hepatic venous shunt through a portal aneurysm complicated by hepatic encephalopathy and pulmonary hypertension

We report a rare case of portal-hepatic venous shunt through an enormous portal aneurysm complicated by pulmonary hypertension. A 66-year-old woman was admitted to our hospital for hepatic encephalopathy. Chest roentgenography revealed pulmonary hypertension. Computed tomography and ultrasound examination demonstrated a shunt between the portal and hepatic veins through an enormous portal aneurysm. The diagnoses of portal-hepatic venous shunt and pulmonary hypertension were confirmed by hepatic venous catheterization and cardiac catheterization. Pulmonary hypertension might result from the effects of vasoconstrictive agents, which should be metabolized by the liver in normal subjects, passing through the intrahepatic shunt into the lung.

A conjugative linear plasmid in Streptomyces laurentii ATCC31255

Plasmid pSLL of Streptomyces laurentii ATCC31255 (wild-type strain P0) is a 93-kilobase linear DNA plasmid that carries a protein bound to each 5' end of the DNA. It was self-transmitted to the pSLL-cured strain by conjugation in solid culture. The pSLL-cured strain carried a circular plasmid, pSLS, and showed a marked decrease in spore formation and thiostrepton productivity, owing to the pSLS. However, by retransmission of pSLL, these things reverted to levels seen in strain P0. Thus, plasmid pSLL suppressed the injurious effects of pSLS on the host mycelia.

Flow cytometric analysis for adhesion of Vibrio cholerae to human intestinal epithelial cell

The adhesion of Vibrio cholerae O1 strains to human intestinal epithelial cell, Intestine 407, was analyzed by flow cytometer. According to positive percentages of Intestine 407 cells adhered by V. cholerae, two groups of V. cholerae strains were classified as follows: more adhesive (more than 50%), less adhesive (less than 50%) strains. In addition, the fluorescence intensity after attachment of V. cholerae was directly correlated to the number of the microorganisms. It was concluded that flow cytometry is a useful and objective method for analyzing adhesion of V. cholerae to cultured cells.

Cloning and sequencing of the hup gene encoding the histone-like protein HSl of Streptomyces lividans

The hup gene encoding the histone-like HU-type protein HSl of Streptomyces lividans TK24 was cloned and sequenced. The deduced N-terminal amino acid sequence, molecular mass (9851 Da) and pI (9.95) are in good agreement with characteristics of the HSI protein. The hup transcript of about 500 nucleotides was detected. The 2.3-kb HincII fragment containing the hup gene hybridized with the AseI fragment C in the 9-10 o'clock region of the chromosome of S. lividans ZX7.

Modification of spontaneous renal lesion of APA hamsters by streptozotocin-induced diabetes

Syrian hamsters of the APA strain (APA hamsters) develop spontaneous mesangial thickening in the renal glomeruli from an early age. They also develop focal and segmental glomerulosclerosis (FSG) at and after 6 months of age. In this study, histopathological, immunohistochemical and lectin histochemical examinations were conducted to clarify the modification of the spontaneous renal lesions of APA hamsters by streptozotocin(SZ)-induced diabetes. Histopathological analysis revealed that the expansion of the mesangial region was more prominent and the thickening of the glomerular basement membrane (GBM) was weaker in SZ-treated animals than in non-treated ones. Immunohistochemical analysis suggested that type IV collagen and laminin were involved in the expansion of the mesangial region and thickening of the GBM. In lectin histochemical analysis, podocytes, capillary endothelial cells, GBM and a part of mesangial region of SZ-treated animals were positive for RCA120 and GSL-I with neuraminidase-pretreatment although they were negative for these lectins in non-treated animals. These results suggest that the spontaneous glomerular lesion of APA hamsters is modified qualitatively and quantitatively by SZ-induced diabetes.

The Yersinia enterocolitica GsrA stress protein, involved in intracellular survival, is induced by macrophage phagocytosis

The Yersinia enterocolitica gsrA gene is a stress protein gene which was originally identified as essential for protecting cells under both extracellular environmental stress and intracellular stress in macrophages due to phagocytosis. The gsrA gene was shown to be a member of the htrA class of genes and to possess a sequence homologous to that of the promoter recognized by a stress-induced sigma factor, sigmaE. In order to study the induction of the potentially sigmaE-controlled gsrA gene in Y. enterocolitica after phagocytosis by macrophages, we identified GsrA by overproducing the protein using a T7 promoter-gsrA fusion. We found that it is translated as an unstable 49,500-Da protein which is processed by removal of an amino acid fragment consisting of 27 residues, resulting in a stable 46,800-Da protein. By radiolabeling proteins specific to bacteria in the J774-1 macrophage-like cell line, we found that the production of GsrA protein is indeed enhanced in bacterial cells growing within macrophage phagosomes. Transcriptional activation of the gsrA gene was determined by using the gsrA promoter-lacZ fusion system. This work provides the first piece of evidence that the sigmaE regulon responds to the stressful environment found in macrophages.

Purification and characterization of a kinin- and angiotensin II-forming enzyme in the dog heart

OBJECTIVE

To purify and characterize a kinin-forming enzyme in the dog heart and to examine the ability of this enzyme to generate angiotensin (Ang) II from Ang I.

METHODS

The enzyme was isolated from heart homogenate using a diethylaminoethyl-Sepharose column, an aprotinin affinity column and a wheat germ lectin-Sepharose 6MB column. Kininogenase activity was assessed with a kinin radioimmunoassay after samples had been incubated with bovine low-molecular-mass kininogen at 37 degrees C for 1 h. Ang I-converting activity was assessed by the quantitation of Ang II formed by incubation of the sample with Ang I at 37 degrees C for 3 h, using high performance liquid chromatography. The enzyme was subjected to 12.5% sodium dodecyl sulphate-polyacrylamide gel electrophoresis, stained by Coomassie brilliant blue and transferred electrically to a membrane with glycoprotein staining.

RESULTS

The purified enzyme is a glycoprotein with an apparent relative molecular mass of 65 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Its kininogenase activity was approximately 20 micrograms bradykinin/h per mg protein at an optimal pH of 8.0. The enzyme also converted Ang I to Ang II at an optimal pH of 6.5. Its specific activity was approximately 2 micrograms Ang II/h per mg protein. Both activities were inhibited by aprotinin, a tissue kallikrein inhibitor. Western blot analysis using polyclonal antibody against this enzyme demonstrated that this enzyme exists both in the myocardium and in the coronary artery.

CONCLUSIONS

The present study showed that the kinin-forming enzyme in the dog heart is a kallikrein-like enzyme that is different from cathepsin D, cathepsin G and chymase. It is also able to Ang I to Ang II. This enzyme might play a role in regulating myocardial perfusion, mainly by generating kinins and in part by forming Ang II.

Purification, characterization and partial primary structure of morphine 6-dehydrogenase from rabbit liver cytosol

Morphinone, a toxic metabolite, was formed from morphine by NAD(P)-dependent morphine 6-dehydrogenase(s) in both the cytosol and microsomal fractions of the rabbit liver at pH 7.4. The enzyme activity in the cytosol fraction was about twice that in the microsomal fraction and NAD served as the preferred cofactor in both fractions. The enzyme in the cytosol fraction was purified to a homogeneous protein by the use of various chromatographic techniques. The enzyme is a monomeric protein with a molecular weight of 36,000 and an isoelectric point of 6.4. The enzyme had a dual cofactor specificity but NAD was more efficiently utilized than NADP. With NAD, the enzyme showed an optimal pH of 9.4, and the Km and Vmax values toward morphine were 0.72 mM and 0.59 unit/mg protein, respectively. The enzyme also exhibited a significant activity for morphine analogs having an unsaturated bond at C-7,8 (codeine, ethylmorphine, and normorphine), alicyclic alcohols (3-hydroxyhexobarbital, 1-indanol, and cyclohexene-2-ol) and benzenedihydrodiol. In the reverse reaction, the enzyme exhibited highly restricted specificity for o-quinones. Sulfhydryl re-agents and quercetin inhibited the enzyme but pyrazole, barbital, and indomethacin had little effect on the enzyme activity. Androstanes, lithocholic acid, and estradiol potently inhibited the enzyme in a competitive manner toward morphine binding. The partial amino acid sequence of the random peptides obtained by the proteolytic digestion of the enzyme, which comprised about 40% of the whole protein, revealed a significant homology to the corresponding regions in the members of the aldo-keto reductase family. These results therefore indicate that the present enzyme is a new and unique member of the aldo-keto reductase family.

Effect of polydextrose on absorption of triglyceride and cholesterol in mesenteric lymph-fistula rats

In most experimental designs, the inhibitory effect of water-soluble dietary fibers on lipid absorption is evaluated by the decrease in plasma lipid concentration or the increase in fecal lipid output. The aim of this study was to evaluate the acute effect of a water-soluble polysaccharide, polydextrose, on lipid transport to the mesenteric lymph using lymph-fistula rats. The mesenteric lymph duct of rats was cannulated, and an infusion tube was introduced into the duodenum. After recovery, a lipid emulsion containing radioactive triolein and cholesteryl oleate was infused into the duodenum for 8 hr. The tested group was infused with the lipid emulsion containing 5% or 10% polydextrose as dietary fiber. Samples from the lymph-fistula were collected, and the luminal contents and mucosa were collected at the end of infusion. Lymph flow in the mesenteric lymph decreased in the polydextrose group after the infusion. The amounts of both triglyceride and cholesterol remaining in the lumen were greater in the polydextrose group, due to decreased transport of lipid into the lymph. These effects were dose dependent in the 5% and 10% polydextrose groups. The results of this study indicate that polydextrose retarded the transport of triolein and cholesterol into the mesenteric lymph.

Metastatic cancer involving pancreatic duct epithelium and its mimicry of primary pancreatic cancer

We investigated 47 autopsy cases of metastatic cancer involving the pancreas. Metastatic disease in nine cases involved the pancreatic duct epithelium. In two cases, metastatic cancer cells showed Pagetoid features. In three cases, pancreatic metastatic disease showed solitary proliferation with focal in situ carcinoma-like lesions mimicking primary pancreatic cancers. Each of these three cases had primary lung adenocarcinomas. Serial sections revealed abrupt borders between the in situ carcinoma-like lesions and the non-cancerous epithelium. Primary pancreatic cancers did not show Pagetoid features or abrupt borders between the cancerous and non-cancerous epithelium. We conclude that the possible diagnosis of pancreatic metastasis should be carefully ruled out in the histological detection of latent primary pancreatic cancer.

Studies on the relationship between adhesive activity and haemagglutination by Helicobacter pylori

The adhesion of Helicobacter pylori to gastric carcinoma cells (MKN45, KatoIII and MKN28) and Intestine-407 cells was tested by flow cytometric analysis. The mean adhesion rates of H. pylori strains to MKN45, KatoIII and Intestine-407 cells were 90.5, 42.7 and 15.1%, respectively. There was no statistical correlation between the adhesion rates to MKN45 cells and haemagglutination (HA) activity of H. pylori strains, although H. pylori strains with high HA activity with human type O erythrocytes tended to adhere effectively to MKN45 cells. No correlation between adhesion and production of vacuolating toxin was observed.

Gastric stump carcinosarcoma with rhabdomyosarcomatous differentiation

Gastric carcinosarcoma is an unusual tumor and its occurrence in the gastric stump is extremely rare. A report is presented here of a unique case of gastric stump carcinosarcoma with rhabdomyosarcomatous differentiation in a 74-year-old man. The patient had undergone partial gastrectomy with gastrojejunostomy (Billroth II method) 30 years previously. The tumor had both adenocarcinoma and sarcoma components, and an immunohistochemical study suggested a focal transition between these components. The main sarcomatous components showed fibrosarcomatous features with a scattered distribution of rounded tumor cells, whose rhabdomyosarcomatous differentiation was immunohistochemically determined. Ultrastructural examination supported the rhabdomyosarcomatous natures. Experience with the present tumor indicates that carcinosarcoma with rhabdomyosarcomatous differentiation can occur in the gastric stump and that this disease is capable of aggressive behavior.

Precise ultrastructural localization of endothelial leukocyte adhesion molecule-1, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 in patients with IgA nephropathy

Using light and electron microscopy, we performed an immunohistochemical study of endothelial leukocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in 15 patients with IgA nephropathy to clarify the localization of these adhesion molecules. The normal portions of 2 kidneys removed due to localized carcinoma and 3 biopsies from patients without glomerular disease were used as a control. By light microscopy, ELAM-1, VCAM-1, and ICAM-1 all showed positive staining in IgA nephropathy, with the intensity of staining following the sequence ICAM-1 > VCAM-1 > ELAM-1. ELAM-1 and VCAM-1 showed a patchy distribution of moderate staining in the tissues, including the mesangium, crescents, adhesions, and tubules. In contrast, there was marked linear ICAM-1 staining throughout the vascular walls. ELAM-1 and VCAM-1 were positive on the basolateral surfaces of a few proximal tubular epithelial cells in association with inflammatory cell infiltration, while ICAM-1 was found on the brush border. ICAM-1 was positive in the glomerular capillary walls and interstitial vessels of the control kidney tissue, while ELAM-1 and VCAM-1 were virtually absent. By electron microscopy, ELAM-1 positivity on the urinary surface of the parietal/visceral epithelial cells was often associated with adherent mononuclear cells in the urinary space. VCAM-1 positivity was increased in the perinuclear space and/or cytoplasm of mesangial cells as well as at the mesangial cell-endothelial cell interface. These findings suggest that ELAM-1 and VCAM-1 may be more closely related than ICAM-1 to the major histopathological changes occurring in IgA nephropathy, including mesangial expansion, formation of crescents and adhesions, and tubulointerstitial injury.

A new experimental model for simultaneous evaluation of aortic and pulmonary allograft performance in a composite graft

A model was developed in pigs for simultaneous evaluation of aortic and pulmonary allograft performance in a composite graft. The composite graft consisted of vascular prosthesis and aortic and pulmonary allografts. Following antibiotic preservation, it was anastomosed to the recipient's thoracic descending aorta by an extrapleural approach without using cardiopulmonary bypass. Aortic blood flow was completely diverted into the composite graft. All 12 recipient pigs recovered well, 4 of which were assigned for the initial study to design the suitable experimental schedule. Calcification readily occurred in the aortic allografts and aneurysmal dilatation without calcification developed in the pulmonary allografts. These morphological findings were consistent with those of previous reports. This model has several benefits. First, aortic and pulmonary allograft conduits can be implanted and evaluated simultaneously under the same conditions by making a composite graft. Second, the magnitude of the operation is minimum, and postoperative circulatory and respiratory management is uncomplicated. Third, wound infection rarely occurs, because the skin incision is made on the back. These preliminary studies suggest that this model will allow future study concerning aortic and pulmonary allograft conduits under different conditions.

Expression of MUC2 and MUC3 mRNA in human normal, malignant, and inflammatory intestinal tissues

MUC2 and MUC3 are prominent mucin genes expressed in the human intestine. Using in situ hybridization with RNA probes, we examined the cellular distribution of MUC2 and MUC3 mRNA in normal, malignant, and inflammatory human intestinal tissues. In normal small intestine and colon, MUC2 mRNA was expressed exclusively in goblet cells and occurred throughout the entire height of the mucosa. MUC3 mRNA was expressed by goblet and columnar cells but was restricted to the villous compartment of the small intestine and the surface epithelium of the colon. Expression of MUC2 and MUC3 mRNA were both markedly decreased in poorly, moderately, and well-differentiated colon cancers but were preserved in mucinous colon cancers. In ulcerative colitis and Crohn's colitis tissues, MUC2 and MUC3 mRNA expression displayed a normal pattern regardless of whether the mucosa manifested active or quiescent inflammation. These findings indicate that MUC2 is goblet cell-specific, whereas MUC3 is related to maturation of intestinal epithelial cells. In colon cancers, the genetic regulation of MUC2 and MUC3 is different depending on the histological type of tumor. The constitutive expression of MUC2 and MUC3 mRNA in inflammatory bowel diseases suggests that these genes may be necessary for maintenance of normal epithelial cell function during inflammation.

Age-related histochemical and ultrastructural changes in renal glomerular mesangium of APA hamsters

Syrian hamsters of the APA strain (APA hamsters) develop spontaneous mesangial thickening in the renal glomeruli from an early age. They also develop focal and segmental glomerulosclerosis (FSG) at and after 6 months of age. In this study, histopathological, histochemical and electron microscopical examinations were conducted to clarify the age-related renal glomerular changes in spontaneous FSG of APA hamsters. Histopathological analysis revealed that expansion of the mesangial region and thickening of the glomerular basement membrane (GBM) in the glomeruli of APA hamsters progressed with age. These age-related changes appeared earlier in male animals. Immunohistochemical analysis suggested that type IV collagen was responsible for the expansion of the mesangial region and thickening of the GBM. In lectin histochemical analysis, positive sites for WGA with and without neuraminidase pretreatment and PNA with neuraminidase pretreatment were detected mainly in podocytes and were expanded with age. Ultrastructurally, the increase in basement membrane-like materials in the mesangial matrix, development of intracellular organella of mesangial cells and migration of a part of the mesangial cell cytoplasm into the GBM were observed at and after 6 months of age. These features suggested that mesangial cells played an important role in the age-related expansion of the mesangial region and thickening of the GBM.

Lingual factors enhance the increase of ornithine decarboxylase activity in rat jejunal mucosa after feeding

Luminal nutrients are the main factors that stimulate ornithine decarboxylase (ODC) activity in rat intestinal mucosa following feeding. The aim of the present study was to determine whether lingual (oral) factors are related to the increase in jejunal ODC activity after feeding. ODC activity in the jejunum and liver was measured 3 hours after refeeding of 48-hour fasted rats. In the first experiment, rats were refed with a regular pellet, powder, or liquid diet. In the second experiment, rats were infused with the liquid diet through a gastric infusion tube following 48 hours' fasting. In the third experiment, the experimental rats had a gastric fistula that allowed free drainage from the stomach of all ingested liquid diet. In the fourth experiment, a truncal vagotomy was performed 1 week before the experiment. The increase of ODC activity in the jejunum of rats fed with the liquid diet was less than that of rats fed with the pellet diet or powder diet. The increase of ODC activity in the jejunal mucosa of rats infused through the gastric tube was less than that of rats fed per os, and the increase of ODC activity in the liver did not differ between these experimental groups. ODC activity did not increase in rats with a gastric fistula. Vagotomy did not affect the increase of jejunal ODC activity after feeding. In conclusion, the increase of ODC activity after feeding was attenuated in rats in which the diet was given by bypassing the mouth. This indicates that lingual factors enhance the increase of ODC activity in the jejunal mucosa after feeding, but the lingual factors alone do not increase ODC activity in the jejunum.

Postabsorptive factors are important for satiation in rats after a lipid meal

We examined satiation after intraduodenal infusion of triglyceride with or without Pluronic L-81 (L-81) in rats. L-81 suppresses lipid transport into mesenteric lymph by preventing the formation of chylomicrons. Under unrestrained conditions, a lipid emulsion was infused into 24-h fasted rats intraduodenally for 8 h. After the infusion, food intake during the first 30 min and blood samples were measured. Food intake after the 8-h lipid infusion decreased significantly (-75%) compared with that of rats infused with vehicle only, and the effect of the lipid meal was time dependent. The satiation effect of the lipid was lost as a result of L-81 treatment, but food intake was still significantly decreased (-22%). The loss of inhibition of food intake by the feeding of lipid plus L-81 was totally reversed by the cessation of L-81 infusion. In rats infused with the lipid emulsion, plasma levels of triglyceride and apolipoprotein A-IV increased significantly. This increase was abolished by the presence of L-81 in the lipid infusate. The present study indicates that postabsorptive factors are important for anorexia observed after a lipid meal in addition to preabsorptive factors. This study further supports our previous conclusion that apolipoprotein A-IV is an important postabsorptive factor for satiation after a lipid meal.

Identification and characterization of the Yersinia enterocolitica gsrA gene, which protectively responds to intracellular stress induced by macrophage phagocytosis and to extracellular environmental stress

Yersinia enterocolitica is able to resist the microbicidal mechanisms of macrophages and to grow within phagocytic cells. Some bacteria including Y. enterocolitica have been shown to respond to the hostile environment in macrophages by producing a set of stress proteins which are also induced by environmental stresses. To understand the role of stress proteins in intracellular survival of bacteria, we identified and cloned a Y. enterocolitica gene, called gsrA (global stress requirement). The gsrA gene was identified because its insertional inactivation by a transposon resulted in the inability of the organism to grow at an elevated temperature and to survive within macrophages after phagocytosis. The gsrA gene was sequenced and shown to encode a basic, 49,500-Da protein. The GsrA protein shows significant amino acid sequence homology to the HtrA stress protein which was originally identified in Escherichia coli. Furthermore, the genetically defined Y. enterocolitica gsrA mutant was constructed and characterized. The insertional mutation of gsrA resulted in inhibition of growth at temperatures above 39 degrees C and greatly increased susceptibility to oxidative and osmotic stresses. The mutant additionally lost the ability to survive and replicate within macrophages. These results, taken together, indicate that the gsrA gene is an essential component of the protection mechanism employed by Y. enterocolitica, allowing it to respond to the intracellular stress in macrophages as well as extracellular environmental stress.

Prevention of bone loss by bisphosphonate YM175 in ovariectomized dogs with dietary calcium restriction

We have evaluated the effects of YM175 (disodium dihydrogen (cycloheptylamino) methylenebisphosphonate monohydrate), a novel bisphosphonate, on bone mineral densities (BMD) at the lumbar spine and forelimb in ovariectomized beagles with dietary calcium restriction. Groups 1 and 2 were given a sham operation and Groups 3-6 were ovariectomized. One month later (month 0), a low calcium diet was given to Groups 2-6. Groups 4-6 were orally treated with YM175 at doses of 0.01, 0.1 and 1.0 mg/kg, respectively, for 18 months. Changes in BMD at the lumbar spine and left forelimb were determined serially by dual energy X-ray absorptiometry. Calcium restriction decreased lumbar BMD by 19% at month 2 and by up to 30% at month 17 compared to its baseline value, but ovariectomy itself had a minimal effect on bone mass in dogs with restricted calcium intake. YM175 (1 mg/kg) prevented the bone loss at month 2 and YM175 at 0.1 mg/kg or more inhibited the BMD reduction at month 17. The magnitude of BMD reduction of the forelimb was less remarkable as compared to that of the lumbar spine. Urinary hydroxyproline excretion and plasma osteocalcin levels were increased by calcium restriction, indicating a high turnover of bone. YM175 reduced hydroxyproline excretion but not osteocalcin levels. These results indicate that YM175 prevents bone loss induced by calcium restriction and ovariectomy through partially normalizing high bone turnover.

Detection of the single-stranded DNA of Streptomyces plasmid pSA1.1 and a binding histone-like protein

Streptomyces plasmid pSA1.1 accumulated single-stranded DNA as replication intermediates in S. lividans; therefore, this plasmid was considered to replicate by a rolling-circle mechanism. A DNA-binding protein (pI > 9.7 and about 10 kDa) was purified on a denatured DNA-Cellulose column, then on a native DNA-Cellulose column. The N-terminal amino acid sequence of this protein has a high homology with bacterial histone-like proteins. In the gel retardation assay, this protein bound with the single-stranded DNA of pSA1.1. We propose that this protein may participate in the replication of pSA1.1.

Analysis of of the epitopes recognized by mouse monoclonal antibodies directed to Yersinia enterocolitica heat-shock protein 60

To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was performed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3.

Computerization of Fujimori's method of waveform recognition. A review and methodological considerations for its application to all-night sleep EEG

This article critically reviews 8 computer implementations of Fujimori's method for EEG waveform recognition, with methodological considerations for the application of this method to the analysis of all-night sleep EEG. Fujimori's method has been considered one of the most appropriate waveform analyses for EEG. This kind of analysis is advantageous for measuring frequency and amplitude of each EEG wave separately. However, current implementations have drawbacks which must be resolved before they can be used on all-night sleep EEG. An optimal sampling rate should be determined which is appropriate to the purpose of analysis. Amplitude thresholds for wave recognition, which are now set arbitrarily, should also be improved. Measurement of waves in higher orders of superimposition is also necessary, although existing systems are limited to the second order. Additional algorithms, such as for the separate detection of sleep slow waves, may be useful. Further applications for Fujimori's method are suggested.

Histaminergic control of mucosal repair in the small intestine

The aim of the present paper was to summarize histamine-mediated repair of rat intestinal mucosa. To evaluate intestinal repair, we examined lipid transport (an index of intestinal mucosal function) after 15 minutes occlusion of the superior mesenteric artery. Rats were pretreated with alpha-fluoromethylhistidine (a suicide inhibitor of histidine decarboxylase, a synthesizing enzyme of histamine), H1-receptor antagonist (chlorpheniramine maleate), H2-antagonist (cimetidine), or H3-antagonist (thioperamide) before ischemia-reperfusion (I/R). Lipid transport to rat mesenteric lymph decreased significantly 24 hours after I/R in all groups tested compared to sham-treated rats. Lipid transport was restored 48 hours after I/R in the vehicle-pretreated control group. Lipid transport was not restored to the control level 48 hours after I/R in rats pretreated with H1-antagonist and a suicide inhibitor of histidine decarboxylase. In contrast, intestinal function was restored to the control level 48 hours after I/R in rats pretreated with H2- and H3-antagonists. These results support our previous findings that newly formed histamine after I/R plays an important role in mucosal recovery through H1-receptors.

Histopathological sequence of hepatic and renal lesions in rats after cessation of the repeated administration of CCl4

The histopathological sequence of hepatorenal lesions in rats after cessation of the repeated administration of CCl4 (0.5 ml/kg, p.o., twice a week for 12 weeks) was examined. In the liver, cirrhotic lesions reduced rapidly after cessation of the CCl4-administration and collagen bundles surrounding the pseudolobules almost disappeared 12 weeks later. In contrast, in the kidney, vacuolation of epithelial cells in the proximal tubules disappeared rapidly but glomerular lesions progressed even after cessation of the CCl4-administration, and marked glomerulosclerosis developed 12 weeks later. Electron microscopically, marked expansion of the mesangial region due to increases of mesangial cells and matrix material, irregular thickening of the capillary basement membrane with mesangial interposition, and various degenerative changes in podocytes including deposition of small-sized droplets were observed.

1,25-Dihydroxyvitamin D3 promotes prostaglandin E1-induced differentiation of HL-60 cells

Human promyelocytic HL-60 cells can be induced by biochemical agents to differentiate in vitro towards divergent types of myelomonocytic cells. It has been reported that prostaglandin E1 (PGE1) can induce granulocytic differentiation and that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) can induce monocytic differentiation. We have now examined the effects of these compounds, both alone and in combination, on HL-60 cell differentiation. PGE1 (1 microgram/ml) or 1,25(OH)2D3 (10 nM) each inhibited cell proliferation over 48-96 hours of treatment, but combined treatment with both agents was necessary to produce a strong inhibition. The percentage of HL-60 cells that can reduce nitroblue tetrazolium (NBT) (a characteristic index of early monocytic or granulocytic differentiation) increased 13-fold within 72 hours of PGE1 treatment, and 1,25(OH)2D3 produced a five-fold stimulation. However, combined treatment (PGE1 plus 1,25(OH)2D3) produced a dramatic 35-fold increase. HL-60 cells did not produce significant levels of nitric oxide (NO) before 48 hours in culture, and treatment with PGE1 or 1,25(OH)2D3 did not significantly increase cellular NO elaboration over control levels. However, combined treatment produced a striking 12-fold increase over control levels. Similarly, combined treatment was necessary to obtain the maximal time-dependent stimulation of cellular lactate dehydrogenase (LDH) activity (a marker of granulocytic differentiation) as well as acid phosphatase (ACP) activity. During this same period of time, PGE1, but not 1,25(OH)2D3, markedly stimulated cellular elaboration of interleukin (IL)-1 alpha, IL-6, and tumor necrosis factor (TNF)-alpha, and 1,25(OH)2D3 cotreatment strongly augmented these effects. Thus, combined treatment with 1,25(OH)2D3 plus PGE1 generally augmented the apparent conversion of these cells, producing synergistic (multiplicative) or additive effects. Furthermore, PGE1 induced within 48 hours the more general phenotypic changes classically associated with the differentiation of these cells: increased expression of chloroacetate esterase (ChAE) (a granulocytic marker), decreases in the nuclear/cytoplasmic ratio (characteristic of development beyond the promyelocyte/myelocyte stage), and major alterations in morphology from floating spherical cells to loosely adherent, elliptical polygons. 1,25(OH)2D3 had little effect itself on most of these parameters, but augmented the morphological changes induced by PGE1 treatment. Within 48 hours, the ability of these cells to reduce the tetrazolium salt WST-1, a general measure of cellular metabolic activity, was increased by PGE1, but not by 1,25(OH)2D3; however, the combination of 1,25(OH)2D3 and PGE1 again produced the strongest stimulation. Similarly, only PGE1 significantly reduced intracellular ATP levels, but combined treatments produced a more pronounced decrease. In summary, our findings suggest that PGE1, not 1,25(OH)2D3, is sufficient to promote rapid in vitro differentiation of HL-60 cells along the granulocyte pathway; however, the PGE1-induced conversion of these cells is markedly augmented by cotreatment with 1,25(OH)2D3. In addition, these converted HL-60 cells preferentially utilize the glycolytic pathway, rather than the citric acid cycle, for production of ATP, a metabolic characteristic that resembles that described for mature granulocytes.

Protein tyrosine phosphorylation induced by epidermal growth factor and insulin-like growth factor-I in a rat clonal dental pulp-cell line

Both epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) produce a dose-dependent stimulation in the rate of cell division in a rat clonal dental pulp-cell line (RDP 4-1). To elucidate the initial mitogen-induced cellular events that may mediate mitogenic action, the effects of EGF and IGF-I on cellular protein tyrosine phosphorylation were examined. In a dose-dependent manner, EGF (1-100 ng/ml) transiently stimulated tyrosine phosphorylation in four major proteins with apparent molecular weights of 220, 180, 140 and 120 kDa, and in five other more minor proteins (90, 80, 65, 55 and 44 kDa). IGF-I (1-100 ng/ml) dose-dependently stimulated the tyrosine phosphorylation of 160- and 140-kDa proteins, and had a smaller effect on the 80-, 65- and 44 kDa proteins. In contrast to the action of EGF, IGF-I-induced tyrosine phosphorylation was sustained for more than 60 min, particularly that of the 160-kDa phosphoprotein. From the results of specific immunoprecipitation/Western-blot analyses, the 180-kDa EGF-sensitive protein could be identified as the EGF receptor (EGF-R). Among the IGF-I-sensitive pulp cell proteins, the 160-kDa protein was identified as insulin-receptor substrate-1. Both mitogenic treatments stimulated the tyrosine phosphorylation of a weak, 44-kDa protein, which we have identified as the extracellular signal-regulated kinase-1. Despite the presence of phosphoproteins of the correct size, neither the IGF-I receptor (IGF-I-R) nor the phospholipase C gamma-isoform could be identified as tyrosine kinase substrates in either treatment. Pretreatment with the tyrosine kinase inhibitor genistein (20 micrograms/ml) significantly inhibited EGF- and IGF-I-induced tyrosine phosphorylation in permeabilized RDP 4-1 cells, and the tyrosine phosphatase inhibitor orthovanadate (1 mM) significantly prolonged the duration of the mitogen-stimulated tyrosine phosphorylation in both intact or permeabilized cells. Phorbol 12-myristate 13-acetate (100 nM), which activates protein kinase C (PKC), inhibited the tyrosine phosphorylation induced by either growth factor. This action was blocked by pretreatment with staurosporine (200 nM, 15 min), a selective PKC inhibitor. However, neither removing external Ca2+ with EGTA (1 mM) nor inducing Ca2+ influx with A23187 ionophore (2 microM) significantly altered EGF- or IGF-I-induced phosphorylation. These findings strongly suggest that authentic EGF-R and IGF-I-R on RDP 4-1 cells are coupled to complex, tyrosine kinase-mediated, intracellular signalling systems that are sensitive to a PKC-dependent mechanism. EGF- and IGF-I-induced tyrosine phosphorylation cascades may have important roles in vivo in the regulation of dental pulp-cell proliferation and ultimately may affect dentine formation.

Different effect of hippocampal granule cell destruction on amygdaloid kindling in Sprague-Dawley and Wistar rats

The hippocampal granule cells receive major inputs via the perforant path from other limbic structures such as the amygdala (AM). In this study, we examined Sprague-Dawley (SD) and Wistar rats, the effect of bilateral destructions of the hippocampal granule cells on the process of AM kindling and kindled AM seizures after completion of kindling. The granule cells were selectively and completely destroyed bilaterally by intra-hippocampal injections of colchicine. The left AM was used as the primary kindling site and the right AM as the secondary site. In SD rats, prior destruction of the granule cells caused a marked delay in the seizure development of both the primary AM kindling and subsequent secondary AM kindling. However, once AM kindling was established in SD rats, the destruction of granule cells was totally ineffective in preventing kindled seizures. In Wistar rats, unlike SD rats, prior destruction of the granule cells failed to change the rate of kindling at the primary and secondary sites. However, Wistar rats showed a transient and marked regression of kindled seizures when the granule cells were destroyed after the completion of AM kindling. In both strains, granule cell destruction had no effect on the re-establishment of kindled seizures at the time of primary-site re-test. These findings suggest that hippocampal granule cells of SD and Wistar rats play different roles in AM kindling.

Immunogenicity of synthetic TF-KLH (keyhole limpet hemocyanin) and sTn-KLH conjugates in colorectal carcinoma patients

Mucins of colorectal carcinomas overexpress the cancer-associated disaccharides Thomsen-Friedenreich antigen (TF) and sialyl-Tn antigen (sTn), making these antigens suitable for active specific immunotherapy. Patients at high risk for recurrent colon cancer, but free from disease after surgical resection, were immunized with synthetic TF and sTn covalently attached by a two-carbon crotyl linker to keyhole limpet hemocyanin (KLH). Four groups of patients were treated with TF-KLH without adjuvant, TF-KLH plus the immunological adjuvant Detox, sTn-KLH plus Detox, or sTn-KLH plus the immunological adjuvant QS-21, and the serological response was monitored. Enzyme-linked immunosorbent assay (ELISA), dot-blot immunostains, and inhibition assays were used to identify antibody responses against synthetic TF and sTn epitopes and against natural antigens, including asialoglycophorin expressing TF antigen, and ovine submaxillary mucin and the human colon cancer line LS-C expressing sTn antigen. Our results demonstrate that vaccines containing TF or sTn-KLH conjugates plus immunological adjuvants Detox and especially QS-21 induced high IgM and IgG antibody titers against the respective synthetic disaccharide epitopes. However, when tested against natural antigens expressing these disaccharide epitopes, IgM antibodies showed weak to moderate reactivity, while IgG antibodies were almost totally unreactive. On the basis of these results we are continuing to test modifications of synthetic TF and sTn epitopes to identify those that induce IgM and IgG antibodies that are more reactive with these antigens as they are expressed on tumor mucins.

Adherence of Helicobacter pylori to cultured human gastric carcinoma cells

AIM

To examine the binding activity of Helicobacter pylori to cultured gastric epithelial cells using flow cytometry.

MATERIALS AND METHODS

We evaluated the adherence of 15 H. pylori strains to cultured gastric cancer (MKN45) cells by flow cytometric analysis. Other bacterial strains were also analysed for their adherence to MKN45 cells. In addition, we examined the effect of fetuin on the adherence of H. pylori to MKN45 cells.

RESULTS

H. pylori strains adhered to MKN45 cells at rates of between 49 and 93.7%, with a mean of 75.3%. In contrast, the rates of Escherichia coli, Shigella flexneri, Vibrio cholerae and Yersinia enterocolitica adherence to MKN45 cells were 69.1, 5.9, 11.7 and 33.1%, respectively. Fetuin had no inhibitory effect on the adherence of H. pylori to MKN45 cells in the flow cytometric analysis.

CONCLUSIONS

A flow cytometric analysis using MKN45 cells proved to be an objective and sensitive method for evaluating the adherence of H. pylori, showing close adherence between this organism and gastric epithelial cells.