Gastric pseudolymphoma

Six histologically proved cases of gastric pseudolymphoma are described. This uncommon benign condition often simulates ulcerated gastric carcinoma radiologically, and pathologically it may cause considerable confusion with malignant lymphoma. Recognition of this condition is important to prevent unnecessary and often hazardous treatment whether by surgery or radiotherapy and to prevent inclusion in series of malignant gastric lymphoma, so that falsely high survival rates are not recorded.

Later stages of development of the periotic duct and its adjacent area in the human fetus

The later stages of development (16-40 weeks in utero) of the periotic duct and its adjacent areas in the human fetus indicate that the critical stages of development occur in four specific time related stages over a six-week period (20-26 weeks). First, the petrous apex ossifies to separate th inferior cochlear vein into the canal of Cotugno and forms the medial wall of the cochlear aqueduct (22 weeks); second, the canalicular otic capsule fuses with the cochlear otic capsule to obliterate Hyrtl fissure and forms of the lateral wall of the cochlear aqueduct (24 weeks); third, progressive bone deposition to the medial surface of the membranous labyrinth and cochlea at the petrous apex elongates the periotic duct and cochlear aqueduct (32 weeks in utero); and fourth, active arachnoid tissue ingrowth into the periotic duct occurs at 20-24 weeks and 34-40 weeks in utero. The terminal event is widening of the CNS opening of the periotic duct at 32 weeks in utero. The periotic duct and cochlear aqueduct length increase with gestation from 25 weeks until term. The periotic duct width remains the same throughout the gestation. The cochlear aqueduct width diminishes with gestational age. The periotic duct remains patent throughout 16-40 weeks in utero.

Influence of fibrinogen levels in dogs on mortality from hemorrhagic and traumatic shock

1) Fibrinogen levels appear related to the outcome of hemorrhagic shock in dogs. 2) Fibrinogen levels can vary with different animals based on location, disease, stress, nutrition, or other factors. 3) Any experiments in hemorrhagic shock (or anything else) should utilize simultaneous and paired controls of animals from the same source or they may be subject to major error.

High perfusion pressure damages the sieving ability of sinusoidal endothelium in rat livers

Fenestrated endothelium lining liver sinusoids forms an ultrastructural sieve between blood and hepatocytes which at physiological perfusion pressures has previously been shown to shield hepatocytes from large triglyceride-rich chylomicrons. In the study reported in this paper, enlargement of endothelial fenestrae at high perfusion pressures has been confirmed and a concurrent increase in trapping of large chylomicrons by the liver noted. These findings suggest the importance of employing physiological perfusion pressures in studies designed to examine hepatic lipoprotein metabolism and also suggest a possible mechanism in the pathogenesis of fatty change seen in the "nutmeg" liver of chronic venous congestion.

Structure-function of the factor VIII complex studied with an immobilized heteroantisera to VIII:C

An antibody was raised in rabbits to the small active fragment of human factor VIII, obtained by Ca2+ dissociation of a human factor VIII preparation made from a multidonor plasma pool. After absorption, the antibody neutralized the factor VIII coagulant activity of normal human plasma, but did not precipitate with any plasma or plasma fractions or neutralize von Willebrand factor (vwf) activity as measured by ristocetin aggregation of fixed washed platelets. Immune beads were prepared by CNBr binding of the partially purified rabbit antibody to 1% agarose beads. Non-immune beads were prepared with IgG fractions obtained from the rabbits before immunization and used throughout as a control. The amount of factor VIII coagulant activity (VII:C) removed from plasma by immune beads was time-dependent and proportional to the amount of beads used, but all of the VIII:C could not be readily removed. Removal of VIII:C by immune beads parallelled removal of factor VIII:antigen, but less VWF activity was removed. Immune beads could be blocked or saturated by treatment with large amounts of normal plasma, but not by von Willebrand disease plasma and only by some haemophilic plasma.

Acute caecal volvulus

Forty-one cases of acute caecal volvulus have been analysed. The diagnosis is rarely made on clinical grounds alone but plain radiography of the abdomen should suggest the diagnosis in nearly 90 per cent of cases. Prompt surgery is imperative. When the bowel is viable, simple caecopexy combined with tube caecostomy is effective in fixing and decompressing the bowel in the short term and prevents recurrence.

Mk in three generations of an English family

Mk was demonstrated in three generations of an English family. The propositus was detected as a result of an incompatibility in cross-match. General serological, biochemical and biophysical aspects have been studied.

Isolated liver perfusion: the choice of anaesthetic

Perfused livers isolated from rats under halothane anaesthesia produced greater amounts of bile, released smaller amounts of aspartate aminotransferase, and had a much greater ability to maintain a constant concentration of glucose in perfusates than those obtained with ether or pentobarbitone. Little or no effect was shown on the ability of the liver to synthesize urea and to retain potassium within the organ. It appears, therefore,that halothane is the anaesthetic of choice when removing the liver from the laboratory rat.

Lung injury induced by leukocytic proteases

Human polymorphonuclear neutrophilic leukocytes (PMNs) contain large amounts of neutral proteases that can degrade elastin, collagen, proteoglycan, and basement membrane. The instillation of one of the purified enzymes (elastase) into dog lungs in vivo causes degradation of elastic fibers and other alveolar septal components and results in anatomic changes similar to those of human pulmonary emphysema. Cigarette smoking is a major risk factor associated with pulmonary emphysema in man. One mechanism for this association may be interference with the regulation of PMN elastase activity by alveolar antiproteases. This possibility is supported by the observation that the oxidizing activity of tobacco smoke inactivates alpha 1-proteinase inhibitor in vitro. Macrophages also secrete an elastolytic protease, albeit at low levels. The short-term exposure of cultured mouse macrophages to cigarette smoke augments the rate of elastase secretion by these cells. Mouse macrophage elastase is not inhibited by alpha 1-proteinase inhibitor or alpha 2-macroglobulin. This unusual property of macrophage elastase may facilitate its attack upon elastin over prolonged intervals despite very low levels of macrophage elastase production. A unified hypothesis of lung injury in pulmonary emphysema is presented, involving both PMN and macrophage elastases and the actions of cigarette smoke. (Am J Pathol 97:111--136, 1979).

Improved performance of the isolated rat liver when perfused with purified bovine serum albumin

Three groups of isolated rat livers were perfused at 35 C with Krebs-Ringer bicarbonate buffer containing commercial bovine serum albumin (BSA) which had been purified by gel filtration on a column of Sephacryl S-200 and used within 12 hr of purification, or BSA which had been purified by gel filtration and stored at -70 C until used. The ability of livers to produce bile, retain potassium, and to maintain a constant level of glucose in the perfusate was greatly improved in the presence of purified albumin which had not been frozen. Such livers also showed the highest rates of urea synthesis, but the rate of release of aspartate aminotransferase (GOT) from cells and the bile salt content of the bile produced were similar to those found with unpurified BSA. Livers perfused with purified albumin which had been stored in the frozen state were slightly inferior to those perfused with nonfrozen albumin in their ability to produce bile and urea, to retain potassium and GOT within cells, and to maintain a constant concentration of glucose in perfusates. The concentration of bile salts in the bile produced by this group was also lower than that found with the other two groups. Overall, isolated rat livers benefited from perfusion with purified albumin, although freeze storage of this material rendered it slightly inferior to the nonfrozen material in its ability to support the liver.

The danger of hemolysis in shock

Intravascular hemolysis is sometimes harmful and often fatal. Other times it is harmless. Dogs were paired and subjected to hemorrhagic shock. One of the pair was given 2 ml/kg of autologous hemolyzed blood before bleeding. The other of the pair was given 2 ml/kg of heparinized autologous blood. All of the animals given heparinized blood survived, whereas, all of the animals given hemolyzed blood died. The animals given hemolyzed blood developed coagulation changes indicative of Disseminated Intravascular Coagulation (DIC), whereas, the dogs given nonhemolyzed blood did not. It is concluded that hemolysis in the presence of shock (slow capillary flow) causes DIC and death. Hemorrhagic shock alone or hemolysis alone was harmless.

A case of atypical polyagglutinability due to Tk-transformation

A case of acquired transient polyagglutinability in a group O, Rh(D) positive female patient, Wa, is described. An unusual finding in the preliminary serological investigation was the non-reaction of the cells with peanut (Arachis hypogaea) extract. The patient's red cells were strongly agglutinated by normal human and rabbit sera from which anti-T had been removed. Electrophoretic mobility studies and tests with polybrene indicated that their sialic acid content was normal. The use of a specific antiserum raised in a rabbit to Wa cells and cross-absorption tests showed that the patient's erythrocytes shared similar antigenic determinants to red cells treated with supernatants from pure cultures of Bacteroides fragilis. The in vitro-modified red cells reacted strongly with BS II lectin prepared from Bandeiraea simplicifolia seeds thus providing confirmatory evidence for Tk transformation on Wa cells. It is concluded that the Tk receptor is probably a more frequent feature of acquired transient polyagglutinability than has hitherto been recognized.

Aedes aegypti in Puerto Rico: environmental determinants of larval abundance and relation to dengue virus transmission

In order to understand adquately the dynamics of vector-borne disease, one must understand how and why vector populations change over time. We describe a long-term, cooperative study of seasonal fluctuation in populations of the Aedes aegypti mosquito in Puerto Rico. During each month of the first 3 years of the project, A. aegypti was found breeding in all five communities studied. Mosquito density was positively correlated with rainfall, the relationship being more marked in the dry, south-coastal part of the island. Discarded tires and animal watering pans were the two most common larval breeding sites. In general, houses in Puerto Rico harbor more potential A. aegypti breeding sites than those in other tropical locations, probably because Puerto Rico is relatively more affluent.

The effect of insulin and hydrocortisone on the isolated rat liver

Isolated rat livers were perfused at 35 degrees C with bovine serum albumin (40 g/l) in Krebs Ringer bicarbonate buffer, or with the same solution containing insulin (0.22 x 10(-6) mol/l), hydrocortisone (0.068 x 10(-3) mol/l), or both hormones together. Observations on the synthesis of bile and on perfusate levels of potassium, aspartate aminotransferase, urea and glucose showed that the presence of insulin and/or hydrocortisone had no beneficial effect on the perfused rat liver in vitro. There is little justification of the isolated liver.

Techniques for arteriography and hydraulic analysis of coronary stenoses in unsedated dogs

This report describes techniques for obtaining pressure flow characteristics and arteriograms of controlled coronary stenoses in unsedated, trained dogs. Coronary flow velocity was recorded by calibrated Doppler velocity transducers linear to three times maximum coronary flow velocity. Pressure losses across stenoses were measured by a differential pressure transducer through small catheters implanted in the distal and proximal left circumflex coronary artery or ascending aorta, a system that was linear within +/-5% to 30 Hz. Coronary stenoses were produced by saline-filled, perivascular cuff constrictors inflated to constant pressure by a pressure regulator. Catheters were implanted in the pulmonary artery for injection of intravenous drugs or diffusible radionuclides and in the left atrium for injection of radionuclide microspheres. Contrast medium was injected through the proximal coronary catheter, and high-resolution arteriograms were obtained by single-spot filming on ultra detail X-ray film and cassettes at end diastole by triggering X-ray exposures from the electrocardiogram. In 13 dogs studied consecutively, the surgical mortality was 15.4%. All implanted instruments functioned for an average of 8 wk per dog.

Myelomatosis and the hyperviscosity syndrome

Eleven patients are described in whom myelomatosis was complicated by the laboratory and clinical features of the hyperviscosity syndrome (HVS). The myeloma type was IgA in nine and IgG3 in two. In those patients with IgA myeloma the HVS was related to the presence of high molecular weight complexes in the serum. Remission of clinical features was obtained in all patients by plasma exchange. Clinical improvement coincided with reduction of whole blood viscosity and in those patients with IgA myeloma, with a parallel reduction of the high molecular weight complexes. The relationship between the IgA complexes and blood viscosity has been examined by physicochemical analysis of purified IgA monomer and polymers and evidence is presented to show that the IgA polymer has a higher intrinsic viscosity and axial ratio than the larger IgM molecule. The significance of these observations is discussed.

The effect of colloid concentration on the functional characteristics of isolated perfused rat liver

The volume of bile produced by isolated perfused rat liver was dependent on the concentration of bovine serum albumin (BSA) in the perfusate, the lowest volumes being obtained with Krebs Ringer bicarbonate (KRB alone and with 70 g/l. BSA in KRB. Increasing amounts were produced as the concentration of BSA was reduced from 70 g/l. to 8.5 g/l. The concentration of bile salts in the bile decreased rapidly during the first hour, but much more slowly thereafter. The highest concentration observed during the first hour was with KRB alone and the lowest with 20 g/l. BSA; subsequently, the highest concentrations were obtained with 70 g/l. BSA and the lowest with 20 g/l. BSA. Urea synthesis was lowest with KRB alone, but increased as the concentration of BSA increased; however, values obtained with 8.5, 20, and 40 g/l. were fairly close together. With KRB alone there was a rapid release of potassium during the first hour, but thereafter the rate of release was similar to that found when BSA was present. The lowest concentrations of potassium were obtained with 20 and 40 g/l. BSA. With KRB alone, GOT was released from the start of perfusion of 300 units per minute. With BSA present, GOT release was delayed 4 hours, and thereafter the rate was dependent on the concentration of BSA, being lowest with 20 and 40 g/l. (200 units per min), higher with 8.5 g/l. (350 units per min) and highest with 70 g/l. (400 units per min).

The effect of temperature on the synthesis of rhinovirus type 2 RNA

The reduced yields of rhinovirus type 2 at temperatures above 37 degrees C were shown to result from the degradation of virus-induced RNA, leaving little RNA available for inclusion into mature infectious virions. The degradation occurred about 6 h p.i., and appeared to be selectively effecting the single-stranded species. Lysosomal nucleases do not appear to have a role in this supra-optimal degradation.

Sensory alienation and interpersonal constraints as correlates of cognitive structure

This research tested the proposition that closed-minded persons will restrict sensory input and interpersonal relationships. 303 high and low scorers on dogmatism, self-attitude, and self-reliance scales were compared for food-avoidance and reference-other relationships. While there was no significant difference in number of foods tasted and rejected, the closed-minded had tried significantly fewer foods. There was no difference in number of reference others but the closed-minded felt significantly greater constraint regarding the perceived importance of, control of, and accountability to their reference others. The theoretical consistency of these findings is discussed.

The use of IgM anti-D coated cells in the deliberate immunisation of Rh-negative male volunteers

Attempts to produce anti-D in rhesus-negative men using reconstituted frozen rhesus-positive cells were unsuccessful. The use of cells coated with IgM anti-D for immunisation stimulates anti-D production, and a comparison between two groups, one having cells coated with IgM anti-D, and the other having identical cells without coating suggests that there is an enhancement of the immune response when IgM-coated cells are used.

Incorporation of galactose into galactosyltransferase

Bovine skim milk galactosyltransferase (EC 2.4.1.22) retained its catalytic activity after partial enzymatic removal of sialic acid and galactose. Desialylated and degalactosylated galactosyltransferase was a galactosyl acceptor in the galactosyltransferase reaction. [14C]Galactose from UDP-[14C]galactose was incorporated into the carbohydrate-depleted galactosyltransferase by native galactosyltransferase. The results suggest that galactosyltransferase participates in the biosynthesis of its glycopeptides of the sialic acid-galactose-N-acetylglucosamine type.

Maintenance of the functional state of isolated rat liver by hypothermic perfusion with an erythrocyte-free medium

Isolated rat liver was studied before, during, and after hypothermic perfusion at 5 C for 24, 48, or 72 hr with an acellular perfusate consisting of 7% bovine serum albumin in Kreb-Ringer buffer containing glucose, penicillin, and streptomycin. Bile production ceased at 5 C but resumed when the temperature was raised to 35 C. The rate of flow and the total amount produced was unaffected by 24 hr of hypothermia but decreased when the cooling period was extended to 48 and 72 hr. The data of other workers was used to show a correlation between bile flow and oxygen consumption by the liver. Cooling also caused the release of potassium into the perfusate but it was quickly reaccumulated after rewarming; however, the extent and rate of reaccumulation decreased as the cooling period increased, as did the ability of the livers to retain the ion. Urea synthesis did not cease after cooling and after rewarming, the rate of synthesis increased as the period of hypothermia was lengthened. The maximum concentration of urea in the perfusate was found when rewarmed livers had produced 200 mumol of urea but at this point, control livers had produced 280 mumol. The concentration of glucose in the perfusate of livers maintained at 35 C showed peaks at 2 and 9 to 10 hr after the start of perfusion. After cooling for 24 hr these peaks arose at 2 and 7 hr after rewarming, but with 48 hr of hypothermia, these peaks were higher and appeared at 2 and 4 hr. When the cooling period was extended to 72 hr, only a single peak was seen 2 hr after rewarming. These results suggest that rat liver can be cooled to 5 C for 24 hr with little effect on its functional characteristics but a marked decline becomes apparent when the cooling period is extended beyond 24 hr. None of the livers studied was transplanted after perfusion and it remains to be seen how the functional tests conducted in vitro correlate with the ability of the livers to support life.

Comparison of nucleic acid content in populations of free-living and symbiotic Rhizobium meliloti by flow microfluorometry

Populations of symbiotic Rhizobium meliloti extracted from alfalfa nodules were shown by flow microfluorometry to contain a significant number of bacteroids with higher nucleic acid content than the free-living rhizobia. Bacteroids with lower nucleic acid content than the free-living bacteria were not detected in significant quantities in these populations. These results indicate that the incapability of bacteroids to reestablish growth in nutrient media may not be caused by a decrease in nucleic acid content of the symbiotic rhizobia.