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Biomedical subjects

S J Proctor

Publications and source records attributed to S J Proctor.

At least 181 records · Page 10Linked to original sources

Increased platelet aggregation induced by glucagon administration.

The effect of 1 mg of intravenous glucagon on platelet aggregation has been investigated in 12 normal subjects pre-treated with salicylate. All subjects demonstrated the expected inhibition of collagen-induced secondary aggregation but retained the normal adenosine diphosphate (ADP)-induced primary aggregation phase 18 h after the salicylate therapy (600-1,200 mg). Subsequent administration of glucagon caused a significant increase in the ADP-induced primary aggregation phase in the 12 subjects. This data indicates that glucagon increases the reactivity of platelets to ADP and may help to explain the common clinical association of raised plasma glucagon, increased platelet aggregation and vascular disease.

Adenosine Diphosphate↗

Intracranial disease in non-Hodgkin's lymphoma.

In an eighteen month period ending October 1978, nine cases of intracranial Non-Hodgkin's lymphoma were diagnosed in this centre. Eight patients had lymphomatous meningitis and one, multiple intracerebral lymphoma deposits. The commonest presentation was with multiple cranial nerve palsies. Despite treatment five patients died within one month of diagnosis and at autopsy three patients were found to have extensive lymphoma involving the meninges. Three patients remain in remission after combination chemotherapy and radiotherapy. The incidence, clinical features, management and prognosis for this condition are discussed.

Adolescent↗

Levamisole in the treatment of cyclical neutropenia.

A child with cyclical neutropenia was observed before and during treatment with levamisole. Marked clinical improvement occurred while on levamisole. Deterioration occurred after stopping treatment. The improvement was not associated with changes in the neutrophil or monocyte counts, nor did tests of phagocytic cell function convincingly demonstrate improvement while the child was on treatment.

Agranulocytosis↗

Malignant myelosclerosis. Myeloproliferative disorder or leukemia?

Four patients with the picture of "malignant myelosclerosis" are described and the relationship of this condition to acute granulocytic leukemia is discussed. It is suggested that there is a leukemic process from the beginning, that the fibrosis of the marrow is reactive rather than neoplastic, and that the disease should not be regarded as an accelerated form of chronic (primary) myelosclerosis. The presence of excessive reticulin in the marrow in acute leukemia, especially when the patient is first seen, indicates a bad prognosis and poor response to chemotherapy. A systemic fungal infection in one patient is described.

Adult↗

Ultrastructural characterization and hepatic pathogenesis of duck plague virus.

Six-week-old white Pekin ducks were inoculated intravenously with duck plague virus (DPV) isolated from wild waterfowl. The virus replicated in hepatic macrophages, hepatocytes, and bile duct epithelium. In ultrathin sections, herpes-like nucleocapsids and virions were found respectively in the nucleus and cytoplasm of infected cells. Typical herpesviral capsids and virions were seen in negatively-stained preparations of duck embryo fibroblasts. Antibodies against Holland-attenuated strain of DPV reacted with virions of this isolate.

Animals↗

Growth and effects of ureaplasmas (T mycoplasmas) in bovine oviductal organ cultures.

Ureaplasmas isolated from the human genital tract and from the genital and respiratory tracts of cattle were grown in association with organ cultures of bovine oviduct (uterine tube). All strains of unreaplasmas multiplied in organ cultures, stopped ciliary activity, and caused histological lesions. Most strains grew well, and 10(8) to 10(9) color-changing units were determined 18 to 144 h after inoculation. Twenty-four to 144 h after inoculation with unreaplasmas, ciliostasis was complete. Ciliostasis was also caused by additions of nonviable cultures at pH 8.8 (or adjusted to 7.4) or washed disrupted cells (100 mug of protein/ml); it occurred in 48 to 96 h. The cilia-stopping effect of nonviable cultures was diminished by heating (56 C for 30 min) and was abolished by boiling. When added to fresh medium in amounts exceeding 25%, nonviable unreaplasmal cultures completely inhibited ureaplasmal growth. By light, scanning, and transmission electron microscopy, cilia-stopping effect was correlated with collapse and sloughing of the cilia (the initial lesion was "bent" cilia), with bulging and vacuolization of secretory and ciliated cells, and finally with disorganization of the epithelium, necrosis, and desquamation.

Animals↗

Anisocytosis and the C-1000 Channelyzer in macrocytic anaemia.

Red cell anisocytosis as assessed using the Coulter Channelyzer C-1000 showed an increase with progressive anaemia in 25 patients with macrocytosis due to B12 and/or folate deficiency. In deficiency of a single factor, the degree of anisocytosis increased with progressive anaemia. In five cases with B12 and folate deficiency combined, anisocytosis was markedly increased out of proportion to the degree of anaemia present. Iron stores were also reduced in four of these cases. It is suggested that objective measurement of anisocytosis is of early diagnostic value in the assessment of multiple haematinic factor deficiency, for example, in macrocytic anaemia associated with malabsorption states and unexpected multiple deficiency states.

Anemia, Macrocytic↗

Duck plague in gnotobiotic ducks.

Four-week-old gnotobiotic and conventional ducks were inoculated orally with duck plague virus. Both groups of ducks died on the third and fourth day after inoculation. Gross and microscopic lesions of duck plague were similar in gnotobiotic and conventional ducks, indicating the synergistic action of species of Salmonella and Pasteurella was not essential for development of lesions.

Administration, Oral↗

Pathogenesis of duck plague in the bursa of Fabricius, thymus, and spleen.

White Pekin ducks were inoculated orally with duck plague virus and killed at 24-hour intervals after inoculation. Spleen, thymus, and bursa of Fabricius were collected and examined by light, fluorescent, and electron microscopy. Necrosis of lymphocytes occurred in the bursa of Fabricius, thymus, splenic periarteriolar lymphoid sheath (T lymphocytes), and splenic germinal centers (B lymphocytes). Viral nucleocapsids were present in the karyoplasm of lymphocytes, but these cells necrotized before virions were formed. Periarteriolar reticular sheath cells and sinusoidal lining cells in the spleen, epithelial cells in Hassall's corpuscle of the thymus, epithelial cells between the cortex and medulla of the follicles in the bursa of Fabricius, and macrophages in all 3 tissues contained nucleocapsids in the nuclei and virions in cytoplasmic vacuoles before necrosis occurred.

Animals↗

Experimentally induced bovine abortion with Mycoplasma agalactiae subsp bovis.

Two pregnant cows aborted 11 and 18 days after Mycoplasma agalactiae subsp bovis was inoculated into the amniotic fluids. The placentas were retained. The fetuses (approx 100 and 150 days of age) were decomposed; M agalactiae subsp bovis was recovered from several tissues of the fetuses, the placentas, and fetal fluids. The same organism was given by intraperitoneal injection to 2 other pregnant (130 and 180 days, respectively) cows. At necropsy of the latter 36 days later, placentitis was severe; M agalactiae subsp bovis was recovered from the placentas of both cows and from the fetus of 1 cow. Control cows given sterile mycoplasma cultural medium by intraamnion or intraperitoneal injection did not abort and were not infected. When first recovered from the bovine placenta and fetus, M agalactiae subsp bovis grew slowly in liquid medium and assumed bizarre colonial morphology on solidified medium. Colonies were small (0.1 to 0.5 mm) and dark and lacked halos, but they reacted specifically in the direct fluorescent antibody test with equine M agalactiae subsp bovis antiserum. After 1 or 2 subcultures, the isolates grew at a normal rate and displayed their usual colonial morphology.

Abortion, Veterinary↗

Pathogenesis of digestive tract lesions in duck plague.

White Pekin ducklings were inoculated orally with duck plague virus. Tissues from the digestive tract were collected daily after inoculation and examined by light, electron and fluorescent microscopy. There were necrosis and degeneration of stratified squamous epithelium of the esophagus and cloaca, epithelium of intestinal crypt and esophageal submucosal glands, macrophages in the lamina propria, and submucosal fibrocytes and lymphocytes. Submucosal hemorrhages occurred after degeneration and necrosis of lymphocytes, macrophages, fibrocytes and epithelial cells. Viral antigens were detected in all these cells by use of fluorescein-labeled antibodies. With the electron microscope, nucleocapsids were seen in the nuclei, budding through the inner nuclear membrane; enveloped virions were present in cytoplasmic vacuoles of macrophages, epithelial cells and fibrocytes. In lymphocytes, nucleocapsids were also in the nuclei, but karyorrhexis and cytolysis occurred before viral maturation was completed.

Animals↗

Ultrastructural changes in bovine lingual epithelium infected with vesicular stomatitis virus.

Vesicular stomatitis virus was inoculated into the dorsal lingual epithelium of three cows. The reaction that developed in 72 h was characterized by severe acute diffuse glossitis with intercellular edema and necrosis of keratinocytes. Virions budded from the plasma membrane and were in the intercellular spaces. Reduplication of desmosomes was a prominent alteration, and normal desmosomes were within the cytoplasm. Intracytoplasmic desmosomes appeared to be formed by endocytosis after breaks occurred in the plasma membrane of one cell; endocytosis of loops of plasma membrane containing desmosomes; and formation of desmosomes on invagination of the plasma membrane.

Animals↗

Venezuelan equine encephalomyelitis in pheasants and chukars.

Phesants (Phasianus colchicus) and chukars (Alectoris graeca) were inoculated with Venezuelian equine encephalitis virus. Antibody titers reached a peak 2 weeks postinoculation and the declined. Viremia was of short duration, clinical signs were not detected, and unionculated cage mates did not develop antibody titers.

Animals↗