bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE BILIARY EXCRETION OF SULFBROMOPHTHALEIN IN THE PIG
Authors: Rose Margaret , Ham John M 
Published: November 2007

SummaryThe characteristics of the hepatic metabolism of Sulfbromophthalein (BSP) have not been described previously for the pig. This is an important deficiency, since the pig is particularly suitable for studies of hepatic physiology and pharmacology which might apply to man.The aim of these experiments was to establish the pattern of serum clearance and biliary excretion of BSP and to determine that dose which would produce a maximal concentration in bile.A dose response and pattern of biliary excretion of BSP was studied at three dose levels administered either as a single bolus or a continuous infusion. All experiments were performed in conscious, conditioned pigs. The patterns of serum clearance and biliary excretion were found to be similar to other laboratory animals and to man. Maximal biliary concentration of BSP was achieved by a single bolus of 5.9 μmol/kg or a constant infusion of 0.59 μmol/kg/min. At these dose levels no significant alteration in bile flow was demonstrated nor was there any correlation between bile flow and BSP excretion. Supra‐maximal doses produced a significant increase in bile flow and with these doses there was a significant positive correlation between bile flow and BSP excretion.
EFFECTS OF THYMIDINE ANALOGUES ON MURINE AND HUMAN CELLS
Authors: Smellie SG , Parsons PG 
Published: November 2007

SummaryThree mouse tumour cell lines grew continuously in 3 μM 5‐bromodcoxyuridine (BUdR). One line (MC‐2) produced a retrovirus and altered in morphology in the presence of BUdR or 5‐iododeoxyuridine (IUdR). These effects, which could be reversed by growth in normal medium, were similar to those reported for the B‐16 mouse melanoma line. The B‐16 line used in this study, however, as well as a variety of human cells (six melanoma lines and three fibroblast strains), were much more sensitive to BUdR, 0·03–0·1 μM being the maximum tolerated levels for continuous growth. No virus production or changes in morphology were induced in these cells by BUdR, deoxyuridine (UdR), 5‐fluorodcsoxyuridine (FUdR) or thymidine (TdR). The results of cell labelling and growth studies showed a correlation of Incorporation of BUdR into DNA with toxicity. Compared on a competitive basis with 1 μM TdR, the order of incorporation of 1 μM nucleosides by two human cell lines was TdR = BUdR = 1UdR ≥ UdR ≥ ≥ FUdR. In contrast to previous reports that FUdR is incorporated into RNA but not into DNA, half of the FUdR label was found in alkali‐stable, DNase‐sensitive material. Over 90% of the other compounds was incorporated into DNA. All of the UdR and 60% of the 1UdR label was incorporated as thymidine: this conversion could be inhibited by labelling in the presence of FUdR.
IMMUNOPRECIPITATION OF BIOSYNTHETICALLY‐LABELLED PRODUCTS IN THE IDENTIFICATION OF ANTIGENS OF MURINE RED CELLS INFECTED WITH THE PROTOZOAN PARASITE, PLASMODIUM BERGHEI
Authors: Knopf Paul M , Brown Graham V , Howard Russell J , Mitchell Graham F 
Published: November 2007

SummaryIn this methodological paper an immunoprecipitation technique has been optimised for the identification of antigens of Plasmodium berghei‐infected blood which react with antibody specificities in a host‐protective antiserum. Extracted 3H‐leucine biosynthetically‐labelled products of infected blood were sequentially reacted and precipitated with sera from mice which had been exposed to P. berghei but which were either non‐protected or protected against lethal infection, protection having been shown to be transferable to naive recipients with the appropriate scrum. As analysed by polyacrylamide gel electrophoresis under reducing conditions, a small number of molecular species was detected in immunoprecipitates using host‐protective sera which were apparently not quantitatively precipitated out of the complex mixture of labelled products of infected blood using sera from non‐protected mice.
FACTORS AFFECTING THE ABILITY OF VARIOUS STRAINS OF ENTEROBACTERIACEAE TO INDUCE TUMOUR RESISTANCE IN MICE
Authors: Vingelis Velta , Ashman Leonie K , Kotlarski Ieva 
Published: November 2007

SummaryPrimary infection of mice with Salmonella enteritidis 11RX (11RX) confers resistance to challenge with 104 LD50 doses of Ehrlich Ascites tumour (EAT). A lipopolysaccharide‐free protein extract of 11RX is capable of eliciting delayed type hypersensitivity (DTH) reactions in these mice and of “recalling” tumour resistance in long‐term 11RX immunised mice, which no longer exhibit any resistance to tumour challenge.In the present study, we have examined the ability of five other strains of Enterobacteriaciae to induce similar effects. Primary i.p. injection of S Chester. S. luton or S. typhimurium G30 into mice resulted in persisting infections and the induction of peritoneal exudate cells (PEC) which were tumouricidal in vitro. DTH reactions could also be elicited in these animals with protein extracts of the homologous or the 11RX strain of salmonella. S. friedenan and E. coli K12, which did not persist in mice, did not elicit tumouricidal PEC and did not sensitize mice for DTH reactions. However, protein extracts from all the five strains could elicit tumouricidal PEC and DTH reactions in long‐term 11 RX‐immunised mice (but not in normal mice).The results imply that a wide range of Enterobacteriaceae may possess antigen(s) which can be involved in tumour resistance, provided that these antigen(s) are presented in such a way that a cellular immune response develops.
ACCELERATED REJECTION OF NEMATOSPIROIDES DUBIUS INTESTINAL WORMS IN MICE SENSITIZED WITH ADULT WORMS
Authors: Hurley James C , Day Karen P , Mitchell Graham F 
Published: November 2007

SummaryAfter oral administration of infective third stage larvae (L3) of Nematospiroides dubius to young mice, intestinal worms persist for many weeks. However, in mice injected parenterally with N. dubius adult worms, the intraluminal intestinal infection arising after L3 administration can be terminated within 3 to 4 weeks. This accelerated rejection is seen in sensitized BALB/c mice (and (CBA/H × BALB/c)F1 mice) and in particular females, but has not been demonstrated in sensitized CBA/H mice. In female BALB/c mice, small numbers of living worms are more effective at sensitization than dead worms, intraperitoneal and subcutaneous implantations are both effective, and products from adult worms incubated in vitro (i.e. ‘excretory/secretory’ (ES) products) will sensitize but only with very high doses in adjuvant. Using appropriate isolated antigen preparations, comparative immunoparasitological analyses in different mice should provide clues on the nature of host‐protective immunities against intestinal nematode infections which are potentially chronic. From the present studies, two groups which differ most dramatically in the consequences of adult worm sensitization are young male CBA/H versus older female BALB/c mice.
AN IMMUNOHISTOCHEMICAL STUDY OF SECRETAGOGUE‐INDUCED SECRETION OF EPIDERMAL GROWTH FACTOR IN THE SUBMANDIBULAR SALIVARY GLANDS OF MICE
Authors: Steidler NE , Reade PC 
Published: November 2007

SummaryRoutine histological and indirect immunofluorescence techniques were used to examine the histological details of changes in the distribution of epidermal growth factor (EGF) in the submandibular salivary glands of mice during secretion. Comparisons were made between glands of normal mice and those of mice given one of a number of secretagogues at various times prior to sampling. Normal submandibular salivary glands in male mice had an extensive system of convoluted granular tubules (CGT), the cells of which contained EGF. When adrenaline or α‐phenylephrine was administered, the CGT cells degranulated, and there was a concomitant loss of intracellular EGF‐positive immunofluorescence. The excretory ducts were engorged with immunofluorescent material, indicating secretion of EGF into saliva, while the ductal cells themselves remained EGF‐negative. The degranulation response could be blocked by phentolamine, but not by propranolol, and no changes in EGF distribution followed the administration of pilocarpine. It was concluded that EGF is secreted, at least partly into the saliva, following an α‐adrenergic response, and that this occurs with degranulation of the cells of the CGT.
ULTRASTRUCTURAL EFFECTS OF THE VENOM OF THE SMALL‐SCALED SNAKE (PARADEMANSIA MICROLEPIDOTUS) ON THE NERVE TERMINALS OF THE RAT DIAPHRAGM
Authors: Hamilton RC , Broad AJ , Sutherland SK 
Published: November 2007

SummaryVenom of the small‐scaled snake (Parademansia microlepidotus) causes a large increase in the number of coated omega figures inserted in the axolemma of nerve terminals. It also causes both a loss of synaptic vesicles and an increase in the number of neurofilaments in the nerve terminals. The actions of the venom are very similar to taipoxin, a pre‐synaptic neurotoxin from the venom of the taipan (Oxyuranus scutellatus). The morphological changes in the nerve terminals caused by the small‐scaled snake venom are not unusual and do not explain the extreme lethality of the venom.
EFFECT OF 5‐AZACYTIDlNE ON DNA METHYLATION IN EHRLICH'S ASCITES TUMOR CELLS
Authors: Tanaka M , Hibasami H , Nagai J , Ikeda T 
Published: November 2007

Summary5‐Azacytidine inhibited in vivo DNA methylation in Ehrlich's ascites tumor cells depending upon the dose at which 5‐azacytidine did not inhibit DNA synthesis significantly. This drug did not inhibit DNA methylation in vitro. The DNA methylase activity in ascitic cells decreased with the increasing dose of 5‐azacytidine. Hypomethylated DNA was obtained from the 5‐azacytidine treated ascitic cells.
THE EFFECT OF OVERNIGHT BILIARY DRAINAGE ON THE HEPATIC EXCRETION OF BROMOSULPHOPHTHALEIN
Authors: MacKinnon M , Kohler M 
Published: November 2007

SummaryThe excretion of bromosulphophthalein (BSP) was studied in rats after depletion of their bile salt pool by overnight biliary drainage. Peak biliary BSP excretion was significantly lower (80% of control value) in animals with a depleted bile salt pool; however, treatment with phenobarbital for 5 days before bile salt depletion prevented a reduction in BSP excretion. These studies support the observation that the hepatic excretion of bile salt is an important factor influencing the biliary excretion of BSP.
CUTANEOUS LEISHMANIASIS IN MICE: DISEASE PATTERNS IN RECONSTITUTED NUDE MICE OF SEVERAL GENOTYPES INFECTED WITH LEISHMANIA TROPICA
Authors: Mitchell Graham F , Curtis Joan M , Handman Emanuela , McKenzie Ian FC 
Published: November 2007

SummaryBALB/c mice differ from CBA/H, (CBA/H × BALB/c)F1 and C57BL/6 mice in being highly susceptible to infection with a particular isolate of the intramacrophage protozoan parasite, Leishmania tropica. This is true over a wide range of challenge doses of promastigotes administered intradermally although, at low doses, male BALB/c are able to restrict the rate at which cutaneous lesions increase in size.Resistance to infection in highly susceptible hypothymic nude (nu/nu) mice of CBA/H and C57BL/6 genotypes can be achieved readily with as few as 106 syngeneic lymphoid cells. In CBA/H.nu/nu mice, Lyl+2− cells in low dose cellular inocula appear to be involved in restoring resistance (i.e. rapid resolution of infection). Surprisingly, a proportion of BALB/c.nu/nu mice injected with syngeneic lymphoid cells are resistant and thus differ from intact BALB/c mice or non‐reconstituted BALB/c.nu/nu mice. In keeping with a high efficacy of limited numbers of T cells following minimal reconstitution, the majority of nude mice implanted subcutaneously with allogeneic, irradiated, neonatal thymus grafts are resistant to L. tropica infection. Genetic features of the node mouse, such as, a defect in skin, may contribute to the extraordinary potency of T cell reconstitutive manipulations. Evidence was obtained that BALB/c.nu/nu skin on BALB/c.nu/+ recipients did not support the development of lesions as readily as normal skin sites.
CELLULAR REQUIREMENTS FOR PRODUCTION AND RELEASE OF THE LYMPHOCYTE COSTIMULATOR
Authors: Andrus Linda , Lafferty Kevin J 
Published: November 2007

SummaryThe lymphocyte costimulator (CoS) is a lymphokine required for the activation of T cell reponses to H‐2 alloantigens or mitogen. CoS activity is found in the supernatant medium of Concanavalin A (Con A) stimulated spleen cells. In this paper we investigate the cellular requirements for CoS production by Con A‐activated mouse spleen cells. Maximal lymphokine production in response to Con A depends on a co‐operative interaction between T cells and a nylon wool‐adherent cell present in the spleen of nude mice. T cells appear to be the major producers of CoS activity, doing so only in response to an initial inductive stimulus supplied by nude spleen cells. The inductive stimulus is found as a soluble factor in the supernatant of Con A‐activated spleen cells, and can also be provided by stimulatory (S+), but not by non‐stimulatory (S−), tumour cells H‐2 identical with the responding T cells. The activation of lymphokine‐producing T cells is thus a two‐signal process, requiring both mitogen and an additional inductive signal. Once activated, homogeneous populations of T cells will release lymphokine in response to mitogen alone.
ALTERATIONS OF DRUG METABOLISM IN RATS EXPOSED TO CIGARETTE SMOKE
Authors: Farrell GC , Cooksley WGE , Cash GA , Powell LW 
Published: November 2007

SummaryIn male rats exposed to cigarette smoke, antipyrine clearance was enhanced to the same extent as has been observed in human cigarette smokers. The activity of aryl hydrocarbon hydroxylase, a representative microsomal mixed function oxidase, was increased significantly in lung and kidney of smoke‐exposed rats compared with controls. The activity of this enzyme in the liver, however, was not altered by cigarette smoke. Although aryl hydrocarbon hydroxylase activity in extrahepatic tissues was significantly enhanced after cigarette smoke exposure, the total drug metabolizing capacity of these tissues remained trivial compared with that of the liver. Hence, extrahepatic drug metabolism is unlikely to account for enhanced antipyrine elimination in cigarette smokers. The present study has established an animal model for studying the changes produced by cigarette smoke which result in enhanced drug metabolism in man.
FURTHER CHARACTERIZATION OF NATURAL KILLER CELLS INDUCED BY KUNJIN VIRUS
Authors: Macfarlan Roderick I , White David O 
Published: November 2007

SummaryThe natural killer (NK)* cell induced one to two days after Kunjin virus infection of BAI.B/c mice is cytotoxic for a wide range of syngeneic, allogeneic and xenogeneic cell lines. It is also weakly cytotoxic for some non‐malignant cells including mouse fibroblasts, macrophages and thymocytes, but not lymph node cells. Levels of lysis of non‐tumour target cells are dependent on their genotype. Furthermore, malignant cell lines may become resistant following transplantation in vivo then susceptible again after culture in vitro.The virus‐induced NK cell is elicited as readily in athymic (nude) as in normal mice. X‐irradiation inhibits its development if administered prior to infection. It is labile on culture at 37°. The cell carries Fc receptors but its NK activity is not antibody‐dependent.
VASCULAR RESPONSES TO REN‐293 (2‐amino‐3[3, 5‐dihydroxyphenyl]‐1‐propanol hydrochloride)—A NEW SYMPATHOMIMETIC AGENT
Authors: Frost BR , Frewin DB 
Published: November 2007

SummaryIn this study the effects of REN‐293 have been examined on the rat tail artery ‘in situ’. It was found that the drug was totally dependent on the sympathetic nerves for its vasoconstrictor action. This action was blocked by phentolamine and attenuated by pre‐treatment of the vessel with tyramine. When a comparative study of the vasoconstrictor effects of several sympathomimetics was performed, it was found that REN‐293 was more potent than tyramine and ephedrine, but less so than etilefrine. It would appear that REN‐293 is of interest as a pharmacological tool for examining sympathetic nerve function, but its usefulness in the therapy of orthostatic hypotension is likely to be limited, due to the very indirect nature of its sympathomimetic action.
SUPPRESSOR CELL ACTIVITY IN A PROLIFERATIVE DISORDER OF T LYMPHOCYTES
Authors: Kupa Ann , Thomas Miriam E , Moore Helen , Bradley J , Zola H , Hooper M , Harding P 
Published: November 2007

SummaryWe report details of the immunological profile of a patient with the candidiasis endocrinopathy syndrome who has developed T‐type chronic lymphocytic leukaemia. The patient is anergic to a panel of delayed hypersensitivity skin tests, and has poor in vitro mitogenic responses, but B cell function in vivo is not impaired. Subsequent functional studies have revealed that cells from the patient have a significant suppressive effect in coculture (p < 0.05) on the responses of healthy donor lymphocytes (NR) to the mitogen phytohaemagglutinin (PHA). A degree of selectivity for the suppressive effect is suggested by the lack of similar effects on coculture responses to the mitogens cocanavalin A (Con A) and pokeweed mitogen (PWM). Mitomycin C treatment of the patient's cells reduced their suppressive activity but significant suppression was still observed in the majority of PHA cocultures. The suppressor activity required the presence of the pattern's cells in cocultures, as no suppression was observed when the pattern's serum or cell culture supernatant were included instead of the patient's cells in NR cultures.
COMPARISONS OF THE NEUROTOXIC ACTIVITY OF THE VENOM OF SEVERAL SPECIES OF FUNNEL WEB SPIDERS (ATRAX)
Authors: Atkinson RK 
Published: November 2007

SummaryA bioassay has been developed to allow comparison of the neurotoxic activity of the venom of individuals of the four most common species of funnel web spiders (Atrax species). In the absence of purified Atrax neurotoxin, the stimulatory action of the venom on skeletal muscle from the cane toad, Bufo marinus, was compared with that of known concentrations of acetylcholine. Several experiments to validate the assay were performed, then venom samples from both male anti female spiders were assayed. It was found that individual female spiders of all Atrax species normally secreted several times as much venom as male spiders, but its neurotoxicity was extremely variable and generally much lower. Both sexes tended to secrete more potent venom in summer than in other seasons. Both also showed some decrease in venom volumes and potencies if repeatedly milked at short intervals. All four Atrax species were found to have approximately equal levels of neurotoxic activity.
A STUDY OF THE GROWTH REQUIREMENTS OF HUMAN TUMOUR CELLS IN TISSUE CULTURE
Authors: Rowbottom Lynette A , Whitehead RH , Roberts GP , Hughes LE 
Published: November 2007

SummaryThe effect of potential growth enhancing substances and other environmental factors on the growth of human cells in culture were examined, For all the cell lines tested the optimum pH range was 7·45‐7·55. Optimum osmolality varied with different cell lines, optimum values being 240 milliosmoles/kg for melanoma cell lines and foetal fibroblasts, 260 milliosmoles/kg for adult fibroblasts and 300 milliosmoles/kg for a breast cancer cell line. A number of hormones were found to affect the growth of the cell lines examined. Insulin and hydrocortisone enhanced the growth of all the tumour cells tested, whereas 17 β‐oestradiol enhanced the growth of breast cancer cells but inhibited the growth of melanoma cells and fibroblasts. Stilboestrol inhibited the growth of all the cell lines but prolactin enhanced the growth of melanoma cells and inhibited fibroblast cell growth. Addition of galactose to the medium stimulated the growth of all cell lines tested, whereas sucrose and Fructose resulted in stimulation of tumour cell growth but had little effect on fibroblasts. α‐thioglycerol and β‐mercaptoethanol enhanced the growth of the tumour cells but had little effect on the growth of fibroblasts. A modified medium has been formulated which enhanced the growth of all the cell lines used when compared with McCoy's 5A medium.
THE EXTENT OF REFLUX OF UNCONJUGATED 14C‐CHOLIC ACID FROM THE LIVER IN SUBJECTS WITH NORMAL LIVER FUNCTION
Authors: Collins DM , Bates JHT , Maslowski AH , McKinnon AE , Campbell CB 
Published: November 2007

SummaryAn improved understanding of bile acid physiology is a prerequisite for the construction of an acceptable model for describing plasma clearance of bile acids. The aim of this study was to determine the extent of reflux unconjugated cholic acid from the liver to the plasma in subjects with normal liver function. The clearance of a bolus injection of unconjugated 14 C‐cholic acid was studied in four subjects using samples collected simultaneously from a peripheral and a hepatic vein. Hepatic extraction ratios calculated directly from the data were found to be essentially constant dining the 20 min following injection, with average values of 0·60‐0·72. This indicates that reflux did not occur significantly in the subjects investigated. These results are interpreted as favouring a model in which exchange of unconjugated 14C‐cholic acid occurs between the plasma and a peripheral compartment with final removal from the plasma to the liver.
AGONIST‐STIMULATED BREAKDOWN OF MYO‐[2‐3H] INOSITOL‐LABELLED PHOSPHATIDYLINOSITOL IN MOUSE PANCREAS
Authors: Tennes Karin A , Roberts Michael L 
Published: November 2007

SummaryAgonist‐stimulated hydrolysis of phosphatidylinositol (PI) in cell membranes has been proposed to lead to an increase of cytosol calcium concentration and activation of the cellular response in certain smooth muscles and glands.A method is described which allows the rapid, reproducible measurement of hydrolysis of phosphatidylinositol in mouse pancreas. The technique involves the in vivo labelling of the pancreas with myo‐[2‐3H] inositol. The majority of the label incorporated into phospholipids is in the form of PI. with only a small proportion of label in di‐ and tri phosphoinositides. Tissue pieces of the labelled pancreata are incubated in vitro in the presence or absence of secretagogues, and the PI in homogenates of these pieces is precipitated with trichloroacetic acid. No PI remains in the acid‐soluble supernatant. This technique does not require the time‐consuming extraction and chromatographic separation of lipids which has been necessary in other assays of PI hydrolysis. Using this method, we have confirmed that PI breakdown is stimulated by carbachol and cholecystokinin‐octapeptide in the presence or absence of extracellular Ca2+. Agonist‐Stimulated hydrolysis of PI was potentiated by extracellular Ca2+, and was not dependent on agonist‐activated Na+ influx.This technique will facilitate the investigation of the importance of PI breakdown in stimulus‐response coupling.
MECHANISMS OF RECOVERY AND ACQUIRED RESISTANCE IN LEWIS RAT EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS
Authors: Willenborg David O 
Published: November 2007

SummaryExperimental allergic encephalomyelitis in the Lewis rat is an acute, self‐limiting disease. Rechallenge of convalescent rats fails to induce disease. Previous experiments provided direct evidence against clonal deletion as the mechanism of recovery from disease and resistance to reinduction and suggested the operation of an active suppression mechanism. The present studies on the mechanism(s) of recovery and resistance suggest (1) resistance is a function of a systemic rather than a local suppressor mechanism, (2) suppression acts by inhibiting induction of immunity rather than expression of immunity and (3) recovery from disease can occur in the absence of detectable anti‐myelin basic protein antibodies, yet these antibodies may play a role in protection against reinduction of disease.