Biomedical subjects
Publications and source records attributed to M J Phillips.
The case of acute lymphoblastic leukemia developing shortly after the diagnosis and treatment of a mediastinal germ cell tumor, is reported. The close temporal relationship of these two rare diseases and the presence of a population of mononuclear cells with features of lymphoblasts in the resected germ cell tumor, suggest that the leukemic process originated from the mediastinal tumor.
The availability of polyclonal and monoclonal antibodies allows immunohistochemical staining (immunofluorescence and immunoperoxidase) procedures to be used by the surgical pathologist, so as to obtain a definite diagnosis in cases where light microscopic examination of tissue sections from biopsy and surgical specimens in inconclusive. Four cases of undifferentiated tumours are described in which only a differential diagnosis could be obtained using light microscopy but a definite diagnosis was achieved when additional information was provided by immunohistochemistry. A scheme is presented for the use of immunohistochemistry to increase diagnostic precision in assessing tumours.
Cytoplasmic microinjection of Ca2+ triggers contraction of bile canaliculi in freshly isolated monolayer cultures of rat hepatocytes. Unseparated paired hepatocytes were used to demonstrate this motility-based phenomenon. Only one cell of the pair was injected, but fluorescein spread from the target cell to the opposite cell; also, the contractions were always uniform, equally involving both hepatocytes that form the canaliculus, indicating that communication exists between the cell pairs. Inhibitors of calmodulin and actin filaments, trifluoperazine and cytochalasin B, respectively, inhibited the Ca2+-induced contractions. Hence, the mechanism of contraction has features in common with actin-myosin based cytoplasmic motility behavior found in other non-muscle cells.
Twenty-one anaplastic tumors were studied by light microscopy (LM), immunoperoxidase staining using anti-epidermal cytokeratin (ECK) and anti-Mallory body cytokeratin (MBCK) antibodies, and electron microscopy (EM), to determine whether an epithelial origin could be confirmed. The tumors were derived from lung, stomach, colon, breast, uterus, kidney, bladder, and mesothelium. By LM, the tumors consisted of either large and polygonal, spindle or small, round cells. With immunoperoxidase staining, 11 (52%) of the anaplastic tumors were positive for ECK, positivity being either absent or only weak in the main tumor mass, but marked in areas of infiltration and metastases. In contrast, all of the anaplastic tumors were positive for MBCK in the main tumor mass, infiltrating areas, and metastases. In the case of adenocarcinomas, staining was either web-like or diffuse throughout the cytoplasm with concentration occurring at the cell surface, whereas in mesotheliomas, the staining was either diffuse or showed focal perinuclear accentuation. Twelve of 13 anaplastic tumors examined by EM showed epithelial features (desmosomes, tonofilaments, lumina, and/or microvilli). As controls, 21 non-epithelial tumors (five melanomas, eight sarcomas, and eight lymphomas) showed no reactivity with either cytokeratin antibody. These studies show that the epithelial nature of undifferentiated and poorly differentiated tumors can be confirmed by immunohistochemistry using anti-cytokeratin antibodies.
The effect of exercise on isoprenaline-induced cyclic adenosine monophosphate (cAMP) production was studied in peripheral-blood lymphocytes obtained from ten patients with atopic asthma, seven subjects who were atopic but did not have asthma and eight non-atopic, non-asthmatic control subjects. The asthma in the atopic subjects was mild only requiring intermittent treatment with inhaled beta adrenoceptor agonists, none of which were taken in the 48 hr prior to the study. Exercise consisted of a standardized 6-min run on a treadmill sufficient to raise the subject's pulse rate to greater than 160 bpm and respiratory function was measured before and at 5, 10, 15, 20, 30 and 60 min after the test. Blood samples were taken 5 min before and at 10 and 60 min after exercise, lymphocytes were separated by density gradient centrifugation and cAMP measured by a competitive radioimmunoassay. Exercise led to a significant decrease (27%) in the forced expiratory volume in 1 sec (FEV1) in the ten atopic asthmatic subjects but no change (less than 3%) in the non-atopic and atopic non-asthmatics. There was no significant difference in the unstimulated cAMP levels before exercise in the three groups, but stimulation with isoprenaline caused a significantly greater rise in cAMP in the non-atopic, non-asthmatic subjects when compared to both the atopic asthmatics and the atopic subjects without asthma. Exercise led to a significant elevation of cAMP in all three groups of subjects, but the same differences between the groups remained.(ABSTRACT TRUNCATED AT 250 WORDS)
Hyposensitization with a tyrosine adsorbed extract of Dermatophagoides pteronyssinus was effective in relieving symptoms in selected patients with perennial rhinitis due to this allergen who had responded poorly to topical application of steroids. There was a significant reduction in the nasal response to allergen after six weekly injections only in the actively treated group, but symptomatic improvement greater than that produced by placebo therapy was only evident after a further 10 months of monthly injections. Significantly more placebo-treated patients considered that therapy was ineffective and withdrew from the study. Only one patient developed significant unwanted effects from the injection therapy and had to be withdrawn from the study. We conclude that hyposensitization with a tyrosine adsorbed extract of Dermatophagoides pteronyssinus can be a safe and effective treatment for adults with perennial rhinitis due to this allergen who have responded poorly to nasal corticosteroids, and that those patients who eventually respond clinically are likely to have a diminished nasal response to allergen after the first 6 weeks of therapy.
The blood supply to regenerative nodules in liver cirrhosis was studied by scanning electron microscopy of microvascular casts. Cirrhotic nodules are surrounded by many arterioles with rich anastomoses that form a perinodular arteriolar plexus: these arterioles connect with sinusoids in the nodules. The portal vein branches, on the contrary, are distorted and compressed by connective tissue. These findings illustrate how the regenerative nodules in liver cirrhosis are mainly nourished by hepatic arterial blood via a perinodular arteriolar plexus.
The inhibition of immediate allergen or histamine induced airflow obstruction by inhaled ketotifen, clemastine, sodium cromoglycate, and placebo was studied in two groups of asthmatic subjects. Single doses of ketotifen (0.5 mg), clemastine (0.5 mg), sodium cromoglycate (20 mg), or placebo were administered by inhalation 45 minutes before bronchial provocation testing at weekly intervals, double blind and in random order. Inhalation of ketotifen and clemastine, but not sodium cromoglycate, caused an increase in the amount of histamine which had to be administered to cause a 20% fall in FEV1 from control levels (PD20-FEV1) compared with placebo. The PD20-FEV1 for allergen increased significantly after inhalation of clemastine and sodium cromoglycate. Clemastine, primarily an H1 receptor antagonist, inhibited airflow obstruction after inhalation of both histamine and allergen. Its inhibitory effect on allergen induced asthma did not differ significantly from that of sodium cromoglycate. Ketotifen, when inhaled in a single dose of 0.5 mg before bronchial provocation testing, showed potent antihistamine activity, but there was no evidence of any additional "antianaphylactic" activity.
The influence of sodium taurocholate on bile canalicular contractions was examined by time-lapse cinephotomicrography of isolated rat hepatocytes in primary monolayer cultures. Frame-by-frame analyses indicates that as the dose of taurocholate increased, the number of contractions increased in a dose-dependent manner up to 5 microM. Because bile canaliculi are the smallest biliary passages across which bile secretion occurs, and because it is known that taurocholic acid within the dose range used in these studies causes a linear increase in bile secretion, the results suggest that canalicular contractions may be a function of canalicular bile secretion.
The hepatic morphological findings in 3 patients treated with amiodarone, a potent and effective antiarrhythmic drug, are reported. An enlarged liver and mild elevation of hepatic enzymes were the most important clinical findings. Fibrosis, cholangitis, mixed inflammatory infiltrate, and cytoplasmic granularity of the hepatocytes were the main histologic changes common to all cases. In 2 of the cases the presence of Mallory bodies was confirmed by electron microscopy. In 1 of these 2 cases, Mallory bodies were also confirmed by immunostaining. Ultrastructurally, numerous cytoplasmic inclusions with a membranous or lamellar structure identical to those described in phospholipidosis were the most striking features seen in hepatocytes, biliary epithelial cells, Kupffer cells, and endothelial cells.
Isolated dog mastocytoma cells sensitized with dog anti-ragweed IgE and challenged with ragweed antigen or incubated with ionophore A23187 or the carboxy-terminal dodecapeptide of platelet factor 4, PF4(59-70), release histamine and concurrently generate leukotrienes B4, C4, and D4. In contrast, the exposure of mastocytoma cells to 0.1-3 micrograms/ml of 15-hydroxyeicosatetraenoic acid (15-HETE) stimulates selectively the generation of leukotrienes, in the absence of histamine release, while 0.1-1 micrograms/ml of compound 48/80 releases histamine without enhancing the generation of leukotrienes. That natural stimuli are capable of selectively activating one synthetic or secretory compartment of mast cells suggests that separate subsets of receptors as well as different biochemical events may serve to mobilize each class of mediators.
This report further evaluates the concept that the interaction of factors that originate within the liver can contribute, regulate or even initiate the actual development of hepatic regeneration after liver cell necrosis or partial hepatectomy. The effect of liver cytosol (100,000 g supernatant), both from intact adult rat liver (NLC) and from adult rat liver remnants that had been regenerating for 24 hours after 70% partial hepatectomy (PH) in posthepatectomy liver regeneration in the rat was studied. The specificity of the growth-controlling properties in liver cytosol was determined using tumor cells. The intraperitoneal administration of NLC after PH resulted in approximately 70-80% inhibition of the peak 3H-DNA specific activity seen in controls at 18 and 24 hours post-PH, with a significant increase in DNA synthesis at 31-40 hours post-PH. The intraperitoneal administration of RLC after PH, augmented the hepatic regenerative response normally produced. Autoradiographic determination of hepatic nuclear labeling confirmed the inhibitory and stimulatory properties of NLC and RLC respectively. Syngeneic NLC or RLC at six and 24 days after subcutaneous tumor inoculation resulted in significant inhibition of tumor growth for both a methylcholanthrene-induced bladder carcinoma (FBCa) and an HTC-hepatoma. The retardation of FBCa growth could be enhanced by administering NLC or RLC every three or seven days. Syngeneic and xenogeneic liver cytosol resulted in dose-dependent inhibition of P815 mastocytoma cell proliferation in vitro. It is apparent from these studies that both stimulatory and inhibitory factors can be extracted from liver tissue that not only influence liver cell regeneration, but also affect tumor growth. Further isolation and characterization of these factors may lead to an understanding of more fundamental problems such as the control of normal and malignant cell growth.
Histologic examination was carried out in 65 cases of childhood rhabdomyosarcoma (RMS), 53 embryonal, and 12 alveolar. Cross-striations were seen on light microscopy in 12 (23%) embryonal and 4 (33%) alveolar tumors. The capacity of immunohistochemical staining (PAP technique) to increase diagnostic accuracy was assessed, using antibodies against myoglobin, the MM isoenzyme of creatine kinase, desmin, calcium magnesium-dependent ATPase of sarcoplasmic reticulum and calsequestrin. Myoglobin was detected in 16 (30%) embryonal and eight (67%) alveolar RMS, higher numbers than obtained by viewing cross-striations on light microscopy. The creatine kinase antibody was slightly better than the antibody to myoglobin and 15 of 25 (60%) embryonal RMS were positive when both specificities were used. The remaining three antibodies were less useful. Of 13 (two alveolar and 11 embryonal) RMS studied by electron microscopy, four showed cross-striations, contained late myoblasts, and were positive for myoglobin. Three additional cases showed only late myoblasts and one of these was positive for myoglobin. Thus, 16 of 25 (64%) of the embryonal and seven of nine (78%) of the alveolar RMS showed either positive immunostaining or ultrastructural features of RMS. This study indicates that a combination of immunohistochemical staining, using antimyoglobin and anticreatine kinase (MM isoenzyme) antibodies, and electron microscopy are useful markers in the diagnosis of childhood RMS.
Cirrhosis is defined as the scarring of the liver acini in zone 3, zone 1 or in both; the resulting nodules are scarred and modified remnants of acini of various orders. The division of the nodules into "micronodules" and "macronodules" is difficult to justify as their two dimensional appearance changes at different planes of section. Early scar formation precedes changes in the microcirculatory dynamics. Sprouting of vascular branches, especially of arterioles, takes the leading role in the development of mature scars, i.e. of fibro-vascular membranes. The fibrous repair is at the same time the road builder for collateral flow. The pathophysiology of the collateral circulation is the basic determinant in the formation of the cirrhotic patterns. The three microcirculatory phases in the cirrhotic process are due to a changeover of the intrahepatic circulatory path from the normal trichotomy of the preterminal vascular branches to convoluted collateral channels. The three phases of the cirrhotic process are: The Triadal Nodule. It receives blood from the TPV and THA and from the perinodular plexus. The nodular parenchyma may already be segregated from the ThV, a situation that leads to portal hypertension. The Para-triadal Nodule. It is a conglomerate of nodules that often are not completely separated from each other; they are derived from neighbouring acini of various orders which receive blood from large triads contained in the perinodular scar. The blood arrives into the sinusoids primarily via the perinodular plexus. Some sinusoids may receive additional blood through sclerosing remnants of terminal afferent branches and through irregular vascular twigs which, along with septa, enter the nodules at various sites. The A-triadal Nodule. It is completely separated from neighbouring nodules by thick scars, its parenchyma totally segregated from afferent and efferent vascular branches. The nodules receive blood only from a dense perinodular plexus of wide capillaries.
The effect of ketotifen was compared with that of clemastine and chlorpheniramine, known antihistamines, and sodium cromoglycate, a drug considered to have mast cell "stabilizing' properties on histamine and allergen wealing reactions in human skin, in random order, double-blind, placebo controlled studies. Ketotifen was significantly more potent in the inhibition of both histamine (P less than 0.001) and allergen (P less than 0.001) skin wealing reactions than either clemastine or chlorpheniramine. Sodium cromoglycate had no significant effect on either histamine or allergen skin wealing reactions in any of the concentrations tested. However ketotifen, like clemastine, had a significantly greater inhibitory effect on histamine than on allergen induced weals (P less than 0.001) and both drugs were shown to act as competitive antagonists of histamine. Ketotifen has been shown to be a potent anti-histamine but there is no evidence from these in vivo studies to suggest that it has any additional inhibitory activity on release of mediators from mast cells in human skin.
Arterial plasma histamine concentrations were measured after exercise in 10 subjects with extrinsic atopic asthma, 10 who were non-atopic and non-asthmatic and seven who were atopic but non-asthmatic, by a single isotope radioenzymatic assay. Significantly higher plasma histamine concentrations were found in the asthmatic subjects before exercise than in the non-atopic controls (p less than 0.05). The mean histamine concentration rose after exercise in all groups but the increased levels were not significantly different from pre-exercise values. Similarly, mean circulating basophil counts increased in all groups after exercise, and a highly significant correlation was found between basophil counts and whole blood histamine concentrations (p less than 0.001). In vitro studies showed that there was a significant correlation between the number of basophils added to plasma samples and the concentrations of histamine subsequently detected. Although the mean concentrations of plasma histamine and whole blood histamine and number of basophils in the atopic control group were intermediate between those found in the atopic asthmatic and non-atopic controls, none of the differences was significant. Venous plasma histamine concentrations after exercise were measured in a further five subjects with extrinsic atopic asthma and five non-atopic, non-asthmatic subjects before and after exercise with the more sensitive and specific double isotope radioenzymatic assay. Concentrations of plasma histamine measured by this assay were about one tenth of those measured by the single isotope radioenzymatic assay. Although a small rise in mean plasma histamine concentration occurred in both groups after exercise there was no significant difference in these levels either between or within the groups. We find no evidence from these studies on measurement of peripheral blood histamine to support the hypothesis that mast cell mediator release is implicated in the pathogenesis of exercise induced asthma.
We observed the motility of bile canaliculi in isolated rat hepatocytes obtained from animals that were pretreated with phalloidin (500 micrograms/kg body wt) for 1 and 3 days. Time-lapse cinephotomicrographs were taken in each experiment and in controls for 16.25 h. As we previously reported in normal hepatocytes, active contractions of bile canaliculi were observed. The number of contractions was 127.6 in controls, compared with 58.0 in 1-day phalloidin pretreated and 16.2 in 3-day phalloidin pretreated groups. The contraction process itself was not normal in the experimental groups, the contraction phase being slow and sustained. The altered canalicular motility depended on the dose of phalloidin administered. These results suggest that the integrity of actin filaments is necessary for normal bile canalicular motility. Further, dysfunction of actin microfilaments with altered canalicular motility may be involved in the pathogenesis of canalicular cholestasis.
Isolated dog mastocytoma cells sensitized with dog anti-ragweed IgE and challenged with ragweed antigen generate the C-6 peptide leukotriene (LT) constituents of the slow-reacting substance of anaphylaxis (SRS-A), LTC4 and LTD4, and the potent leukocyte chemotactic factor, LTB4, as well as 15-hydroxyeicosatetraenoic acid (15-HETE), 12-HETE, and 5-HETE. Antigen challenge evoked a mean maximum production of LTC4, LTD4, and LTB4, respectively, of 16.3 ng, 4.6 ng, and 6.7 ng per 10(6) mastocytoma cells within 5 min at 37 degrees C, which was maintained for up to 45 min. The maximum production of leukotrienes by mastocytoma cells activated with optimum concentrations of 0.2 to 1 microM calcium ionophore A23187 was 35% to 50% greater than that achieved by antigen challenge, without alterations in the relative quantities of leukotrienes, but was realized only after 30 min at 37 degrees C. The leukotriene products of mastocytoma cells were identified by high-performance liquid chromatography, spectral properties, and immunoreactivity with mono-specific antisera, and exhibited the same concentration-dependence of biologic activity as authentic synthetic standards. The ratio of quantities of C-6 peptide leukotrienes generated was attributable in part to the rate of peptidolytic conversion of LTC4 to LTD4 in the mastocytoma cells, which was 33% per 30 min at 37 degrees C. The rapid maximum response to IgE-dependent stimulation and the unique spectrum of products distinguishes the secretion of leukotrienes by dog mastocytoma cells from that by basophils and some other types of mast cells and suggests diverse contributions of mast cell leukotrienes to immediate and late hypersensitivity reactions.