Reduction of cell proliferative activities of gastric stump adenomatous hyperplasias after bile reflux diversion in rats

Previously we reported the majority of lesions induced by bilereflux, in the absence of chemical carcinogens, in the rat remnantstomach to consist primarily of gastric type and secondarilyof intestinal type cells, and that they are reversible afterdiversion of bile reflux. The present study was designed toevaluate changes in proliferative activities in cells of eachtype under these conditions. The frequency of adenomatous hyperplasia(AH) induced in the gastric stump mucosa by duodenal contentreflux after Billroth II partial gastrectomy (BII) increaseduntil the 54th week of the experiment. Roux-en-Y (RY) surgicalprocedure which prevents duodenal reflux performed at the 24thor 36th week after BII led to a decrease in AH. Cell contentof the lesions was analyzed using routine H&E staining,immunohistochemical staining for pepsinogen isoenzyme 1 andhistochemical procedures for mucins (paradoxical concanavalinA, galactose oxidase Schiff and sialidase galactose oxidaseSchiff reactions) and proliferation in each compartment evaluatedby an immunohistochemical method using bromodeoxyuridine (BrdU)and a monoclonal antibody against BrdU. At the 54th week thenumber of BrdU-labeled cells per normal pyloric column was significantly(P < 0.05) increased to 10.63/pit after the BII operation,while it diminished to 5.23/pit after RY diversion, this beingthe same level as with the RY procedure alone. AH maintaineda high rate of BrdU incorporation at 12.7% after BII operation,which was also significantly reduced (P < 0.01) to 7.0% bythe RY surgery. The intestinal type cell showed highest (22.2%),the surface mucous type cell showed the next (16.5%) and thepyloric gland type cell showed lowest (5.2%) BrdU labeling indicesafter BII operation. All the cell types in AH showed similarproportional decreases in BrdU incorporation after RY diversion.Thus surgical intervention reverses the cell proliferation causedby bile reflux in the gastric stump.     

The effect of glibenclamide on the production of interstitial adenosine by inhibiting ecto-5′-nucleotidase in rat hearts

1. Adenosine exerts cardioprotective effects on the ischaemic myocardium. The production of adenosine in the ischaemic myocardium is attributed primarily to the enzymatic dephosphorylation of adenosine 5′-monophosphate (AMP) by 5′-nucleotidase. We determined the activity of 5′-nucleotidase in rat hearts. The objective of the study was to determine the effects of ATP-sensitive K⁺ (K_ATP) channel antagonists (glibenclamide and 5-hydroxydecanoate) on the production of adenosine, by use of a flexibly mounted microdialysis technique.
2. Rats were anaesthetized and the microdialysis probe was implanted in the left ventricular myocardium, followed by perfusion with Tyrode solution. The baseline level of dialysate adenosine was 0.51±0.09 μM (n=16). Introduction of AMP (100 μM) through the probe increased the dialysate adenosine markedly to 9.79±0.43 μM (n=12, P<0.001 vs baseline), and this increase was inhibited by the ecto-5′-nucleotidase inhibitor, α,β-methyleneadenosine 5′-diphosphate (100 μM), to 0.76±0.12 μM (n=8). Thus, the dialysate adenosine noted during the perfusion of AMP originated from dephosphorylation of AMP by ecto-5′-nucleotidase, and the dialysate level of adenosine attained reflects the ecto-5′-nucleotidase activity in the tissue in situ.
3. Glibenclamide (0.1–100 μM) decreased the adenosine concentration measured during the perfusion of AMP (100 μM) in a concentration-dependent manner (IC₅₀=10.5 μM). In contrast, 5-hydroxydecanoate (10–100 μM) did not affect the concentrations of dialysate adenosine, measured in the presence of AMP (100 μM). These results suggest that glibenclamide inhibits the activity of endogenous ecto-5′-nucleotidase and decreases the concentration of adenosine in the interstitial space of rat ventricular muscles in situ.

     

Accumulation of L-[2-(F-18)]fluorophenylalanine in peri-infarct area in a patient with acute cerebral infarction

We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain.     

The anti-proliferative effect of proliferating cell nuclear antigen-specific antisense oligonucleotides on human gastric cancer cell lines

The proliferating cell nuclear antigen (PCNA) is a nuclear protein that leads DNA synthesis by the DNA polymerase delta. As the PCNA gene is strongly expressed in invasive gastric cancer cells with high proliferative activity, PCNA is suspected of playing an important role in the proliferation and advancement of gastric cancer. Thus, the effects of antisense oligonucleotides specific for PCNA mRNA were examined in seven gastric cancer cell lines. It was found that treatment with antisense oligonucleotides at concentrations of 10–40 M dose-dependently inhibited the growth of all cell lines; however, random sequence oligonucleotides did not modify the proliferation of any type of cells. These results indicate that PCNA is essential for cell proliferation in gastric cancer cells, and that the growth inhibitory effect results from the inhibition of PCNA gene expression. Therefore, PCNA-specific antisense oligonucleotides may be effective in the treatment of gastric cancer.     

Public health services in Bangladesh with special reference to systems and trends of vital statistics

Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy for providing essential minimum health care to all has been actively pursued. An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on recent trends based upon relevant data and information. Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local, and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services to enhance the services of health facilities.     

An effective device to keep the sternum open

(Received for publication on Oct. 6, 1997; accepted on July 7, 1998)     

Intrathoracic omental herniation through the esophageal hiatus: Report of a case

(Received for publication on Dec. 8, 1997; accepted on July 7, 1998)     

Immunohistochemical study of crooke’s hyaline change

Crooke’s hyaline change of the human pituitary gland appears as an intracytoplasmic accumulation of fine filaments under electron microscopy. This study was attempted to identify the fine filaments by immunohistochemical methods. Twenty-eight postmortem, formalin-fixed or chrome-alum-fixed, paraffin-embedded pituitary glands revealing unequivocal Crooke’s hyaline change on hematoxylin and eosin stain were selected for this study. To demonstrate Crooke’s cells and fine filaments simultaneously, mirror image sections were sliced and stained with the following monoclonal antibodies using an avidin-biotin-peroxidase complex method: an antibody against synthesized adrenocorticotropic hormone 1–24, human cytokeratins (55–57 kilodalton [kd] and 68 kd), porcine vimentin (57 kd), porcine desmin (53 kd), bovine neurofilaments (70, 160, and 210 kd), human glial fibrilfary acidic protein (GFAP) (56 kd), and chicken actin. Crooke’s cells showed a variable intensity of cytoplasmic staining for 55- to 57-kd cytokeratins, from focal to more even and intense staining revealing a characteristic wide brown ring around the nucleus or beneath the cell membrane. The most severely affected cells were totally replaced by dark brown reaction products with no secretory granules detectable in the cytoplasm. However, 68-kd cytokeratin could not be unequivocally demonstrated. Crooke’s cells were all negative for vimentin, desmin, neurofilaments, GFAP, and actin. Thus far, it could be concluded that Crooke’s hyaline change was composed of intermediate-subunit molecular weight cytokeratins that are normal constituents of the ACTH cell.     

Effects of sodium and temperature on tension in isolated canine coronary artery

The effects of sodium and temperature on tension of isolated canine coronary arterial strips were studied.In 20mEq·l ^–1 K solution, the strength of tension was inversely related to the Na concentration. At 37°C, the tension was significantly increased at 70mEq·l ^–1 Na and below. The tension was gradually suppressed by lowering of the temperature from 37°C to 10°C. At 10°C, tension did not developed significantly at Na concentrations between 127mEq·l ^–1 and 12mEq·l ^–1.It was concluded that the decrease in Na concentrations increased the tension of the canine coronary artery and the lowering of temperature supressed the tension inducted by the decrease in Na concentrations.(Yoshida K, Fujii Y, Ina H, et al.: Effects of sodium and temperature on tension in isolated canine coronary artery. J Anesth 5: 56–59, 1991)