Ultrasonography and computed tomography in adenomyomatosis of the gallbladder

Ultrasonography and computed tomography were performed in 4 patients with adenomyomatosis of the gallbladder of segmental or diffuse type. Cholecystectomy was performed in all cases, and the diagnosis of adenomyomatosis was confirmed histopathologically. Ultrasonography revealed diffuse or segmental thickening of the gallbladder wall with small intramural diverticula. Small stones were also found. The characteristic findings of adenomyomatosis at computed tomography were soft tissue density masses in the gallbladder fossa, associated with a well-delineated, distinct tumor-free space between the mass and the liver, and with small intramural diverticula and calcified stones within the mass. Ultrasonography and computed tomography demonstrate a characteristic appearance of adenomyomatosis.

Growth inhibition of Streptococcus mutans by cellular extracts of human intestinal lactic acid bacteria

The in vitro growth of Streptococcus mutans was completely inhibited by water-soluble extracts from cells of various intestinal lactic acid bacteria identified as Streptococcus faecium, Streptococcus equinus, Lactobacillus fermentum, and Lactobacillus salivarius. The growth inhibition was dependent on the concentrations of the extracts. In contrast, the extracts did not inhibit the growth of the major indigenous intestinal lactic acid bacteria isolated from humans. These lactic acid bacteria were not acutely toxic in mice.

[Experimental study on influence of obstructive jaundice and vagotomy upon stress ulcer in rats]

The effect of water immersing and restraint stress upon the gastric acid secretion and gastric mucosal defensive factors was investigated in rats with special reference to the influence of obstructive jaundice and vagotomy. The results obtained were as follows. Water immersing and restraint stress ulcer may be caused by increased gastric acid secretion and deteriorated gastric defensive factors. Enhanced ulceration in jaundiced rats may be caused by severely damaged gastric defensive factors, rather than by the increased gastric acid secretion. Vagotomy itself, cannot inhibit stress ulceration completely, especially under the condition of damaged gastric defensive factors.

Exaggerated acetaldehyde response after ethanol administration during pregnancy and lactation in rats

The exaggerated blood acetaldehyde response that has been reported after ethanol administration to pregnant rats was found to be the beginning of a much larger alteration occurring during lactation. Indeed, at the end of pregnancy, we confirmed a 4-fold increase in the acetaldehyde values above nonpregnant values after an intragastric dose of 3 g/kg ethanol. During gestational days 1 to 17, the levels did not differ. After delivery, the exaggerated acetaldehyde response to ethanol was increased, producing acetaldehyde concentrations 15-fold greater than in nonlactating controls. This response returned to nonpregnant levels with weaning and could be abolished by removing the pups at birth. The intensified response was associated with both an enhanced rate of ethanol oxidation and a decreased low Km aldehyde dehydrogenase activity in liver mitochondria. At the end of pregnancy, measurable concentrations of acetaldehyde were found in umbilical venous blood and fetal blood. However, they amounted to only one-quarter of maternal values whereas ethanol levels were similar. Thus, during late pregnancy and lactation, there is a marked increase in maternal blood acetaldehyde after ethanol intake. In the presence of a normal placenta, however, an acetaldehyde concentration gradient exists between the mother and the fetus.

An in vitro preparation and study of cells in cat visual cortex

We have described full details of the preparation of slices from the visual cortex of cats. Then, we presented the results concerning the effects of the deprivation of glucose from the circulating medium on neuronal activities in the slices and the electrophysiological criteria for identifying glial cells in the sliced brain tissues. The results indicated that transsynaptic responses were reversibly blocked within 10-20 min, while nonsynaptic responses continued for more than 60 min in the glucose-free medium. We showed that glial cells could be identified according to the criteria proposed in in vivo experiments.

Pathogenesis of precirrhotic portal hypertension in alcohol-fed baboons

To study mechanisms and anatomic correlates of precirrhotic portal hypertension, we measured portal pressure either at laparotomy (in the portal vein) or by hepatic vein catheterization (wedge pressure) in 24 pairs of baboons fed 50% of energy either as ethanol or isocaloric carbohydrate (controls) for 4 mo-9 yr. On liver biopsy 7 had simple fatty liver; none had portal pressure exceeding the control range (2.7-13.0 cmH2O). The remaining 17 alcohol-fed baboons had fibrous tissue deposition around the terminal hepatic venules and adjacent sinusoids. The mean portal pressure was significantly increased (15.0 +/- 1.4 cmH2O) compared with the value in baboons with fatty liver (9.6 +/- 0.9 cmH2O) and in controls (8.0 +/- 0.6 cmH2O), with 8 animals exceeding the control range. Estimated hepatic blood flow was unchanged. Alcohol feeding resulted in increased hepatocyte size in both the fatty liver and fatty liver with fibrosis group; however, portal pressure did not correlate with alterations of cell size, liver volume, hepatic triacylglycerol, and protein contents. By contrast, for veins of comparable size, there was a significant correlation (r = 0.6666, p less than 0.01) between the thickness of the perivenular fibrous rim and portal pressure. Perivenular fibrosis was commonly associated with adjacent perisinusoidal fibrosis and this lesion also correlated with portal pressure. Furthermore, if one postulates that increased cell size causes enhanced pressure with secondary fibrosis, the latter should have first occurred "upstream," in the mid and portal zones. Sequential biopsy specimens, however, showed that fibrosis first appeared in the perivenular areas, suggesting that, in most instances, increased pressure is in fact secondary to the perivenular fibrosis.

[Gastric mucosal defensive factor in various gastric diseases--with special reference to the influence of the operative insult and obstructive jaundice]

Gastric mucosal defensive factor plays an important role in the pathogenesis of various gastric diseases as well as aggressive factor such as acid. Gastric mucosal defensive factor of various gastric diseases and the relation to acid secretion were studied. The influence of operative insult and obstructive jaundice on gastric aggressive and defensive factors was also studied. Defensive factor was investigated using gastric transmucosal potential difference (PD). The results obtained were as follows: PD showed low value in the gastric diseases with the mucosal lesion such as gastric ulcer, stress ulcer and bleeding gastric ulcer. Particularly the last two diseases, which had active mucosal bleeding, showed remarkably low values. PD tended to increase following acid secretion but had no significance. Operative insult seemed to cause transient increase of intragastric pH and deterioration of gastric defensive factor, and the change was enhanced by obstructive jaundice.

Effect of cimetidine on gastric mucosal barrier in dogs

The effect of cimetidine on the gastric mucosal barrier (GMB) was investigated in adult mongrel dogs with a Heidenhain pouch. A linear correlation was found between the net flux of Na+ and H+, and transmucosal electrical potential difference (PD). The PD was thus considered to be a good indicator for the degree of impairment of the GMB which can be determined easily with high reproducibility. When irrigated with HCl alone, there was a slight, though not significant, upward tendency of the PD following intravenous cimetidine. The destruction of the GMB during perfusion with HCl plus sodium taurocholate resulted in a marked reduction of the PD. This response of the PD was significantly reduced by the injection of cimetidine. These results indicate that cimetidine protects the GMB from impairments by bile acid.

[Experimental study on acute gastric ulceration in rat--including influence of obstructive jaundice and vagotomy]

Prognostic indicator for acute gastric ulceration was experimentally investigated using water immersed and restrained rats, with special interest in influence of obstructive jaundice and effect of vagotomy. The results obtained are as follows: Intragastric pH and gastric mucosal potential difference (PD) faithfully reflected the ulcer index. This shows that continuous monitoring of these two parameters may be of clinical use as indicator for acute gastric ulceration in critically ill or postoperative patients. Water immersing and restraint stress ulcer may be caused by imbalance between gastric offensive and defensive factors as a result of progressively increasing gastric secretion and progressively deteriorating gastric mucosal barrier. Gastric ulceration was enhanced in rats with obstructive jaundice, probably because of compromised defensive factor. Prophylaxis of acute gastric ulceration with or without obstructive jaundice may not be attained by vagotomy alone; an adequate maintenance of defensive factor seems to be also necessary.

Zonal redox changes as a cause of selective perivenular hepatotoxicity of alcohol

Alcohol-induced lesions predominate in perivenular zones of the liver. To test the hypothesis that ethanol aggravates hypoxia in this zone by stimulating oxygen consumption, we measured hepatic venous pO2 after ethanol-administration to both alcohol-fed baboons (with perivenular lesions) and their controls, and found no changes: the stimulation of oxygen consumption was fully offset by a parallel increase in blood flow. Despite the lack of hypoxia, ethanol increased lactate/pyruvate (L/P) 15-fold in hepatic venous blood and only 3-fold in liver tissue. Addition of lactate to increase arterial L/P several-fold produced no changes in the hepatic venous ratio, indicating that the equilibrium between this ratio and the cytosolic redox state was reached in one passage through the liver. Thus, the higher L/P in hepatic venous blood most likely reflects an enhanced redox shift in perivenular zones. In isolated hepatocytes, a pO2 comparable to that normally prevailing in perivenular zones mimicked the exaggeration of the ethanol-induced redox shift and aggravated inhibition of protein synthesis. We therefore propose an alternate mechanism for the selective perivenular injury; namely, that the low pO2 normally prevailing at this site aggravates the redox-linked toxicity of ethanol.

Origin of breath acetaldehyde during ethanol oxidation. Effect of long-term cigarette smoking

Oropharyngeal microflora and lung microsomes can produce acetaldehyde from ethanol. Therefore we evaluated the suitability of breath acetaldehyde analysis to estimate blood acetaldehyde. We found that in individuals who develop high acetaldehyde concentrations (over 50 micro M) after alcohol ingestion (such a s oriental "flushers"), the acetaldehyde concentration in end-expiratory air reflects the blood levels. However, in the majority of non-Oriental subjects who develop very small concentrations of acetaldehyde in the blood (less than 5 micro M), the production of acetaldehyde in the respiratory tract accounted for most of the acetaldehyde present in end-expiratory samples. Under the latter conditions, breath acetaldehyde did not correlate with blood levels. The production of acetaldehyde from ethanol in the respiratory tract was markedly exaggerated in long-term cigarette smokers. Rinsing the oropharyngeal cavity with pyrazole (an alcohol dehydrogenase inhibitor) prior to sampling reduced, but did not eliminate, the local contribution to breath acetaldehyde, especially in smokers. In baboons, blood acetaldehyde could be accurately estimated from breath analysis only when the upper respiratory tract was completely excluded by collecting the expired air through an endotracheal tube. Thus, to assess blood acetaldehyde, breath acetaldehyde measurements cannot be substituted for direct measurements, except for those few conditions known to be associated with very high blood levels.

Mechanism for selective perivenular hepatotoxicity of ethanol

Chronic alcohol administration to baboons results in perivenular lesions in the liver. To study possible mechanisms, the effect of ethanol on splanchnic oxygen consumption was measured. Acute ethanol administration increased splanchnic oxygen consumption in the control baboons, but the consequences of this effect on oxygenation of the perivenular zones were offset by a concomitant rise in blood flow, resulting in unchanged hepatic venous oxygen tensions. In alcohol-fed baboons, splanchnic oxygen consumption was not increased, either in the withdrawal state or after ethanol infusion. To study the magnitude of the shift in redox state induced by ethanol in the perivenular zones, we compared the effects of ethanol on the lactate/pyruvate ratio in hepatic venous blood (an approximation of that in perivenular hepatocytes) with the ratio in total liver. Prior to ethanol infusion, the lactate and pyruvate were the same in liver and in hepatic venous blood. By contrast, in all baboons, ethanol produced a much greater rise in the lactate/pyruvate ratio and decreased pyruvate more in hepatic venous blood than in total liver. Moreover, in isolated rat hepatocytes, the ethanol-induced redox shift was markedly exaggerated by oxygen tensions similar to those found in centrolobular zones. This suggests that the normally low oxygen tensions existing in perivenular zones exaggerate the ethanol-induced redox shift, a change which may contribute to the exacerbation of the damage in the perivenular area of the hepatic lobule.

Nociceptive and non-nociceptive responses of neurons in the medial subthalamic region and lateral hypothalamic area of cats and their relationship to the effects of morphine and pentazocine

Single neuronal activity was recorded extracellularly from the Forel's field (FH), subthalamic region immediately rostral to the FH (STRF), rostral end of the medial subthalamic region (RE) and lateral hypothalamic area (LHA) of the anesthetized cats. Many of the FH, RE and LHA neurons were excited by nociceptive stimulation such as pinching the skin with serrated forceps and/or intra-arterial injection of bradykinin. These nociceptive neurons were also excited by non-nociceptive stimulation such as tap of deep tissues, bending hairs with an air-puff and/or joint rotation. On the other hand, inhibition by both nociceptive and non-nociceptive stimuli was seen in and around the rostral end of the FH including STRF. Their receptive fields were large. After intravenous administration of either morphine or pentazocine, most nociceptive neurons became unresponsive to nociceptive stimuli, although they were driven by non-nociceptive stimuli. This suggests that morphine and pentazocine have a specific antinociceptive action on these nociceptive neurons. Intravenous naloxone reversed the antinociceptive action of morphine, but failed to reduce the action of pentazocine. This differentiation has an important functional significance.