Mycoplasma sturni sp. nov., from the conjunctiva of a European starling (Sturnus vulgaris)

Strain UCMF(T) (T = type strain) was isolated from the conjunctiva of a European starling (Sturnus vulgaris) with conjunctivitis. Colonies grown on conventional mycoplasma agar possessed the typical fried-egg appearance observed with many mycoplasmal species. Electron micrographs of ultrathin sections of UCMF(T) revealed a pleomorphic cellular morphology; the cells ranged from spherical to elliptical or flask shaped. The cell size ranged from 0.3 to 0.5 microns. Strain UCMF(T) grows well in a variety of mycoplasma broth formulations at 25 degrees C, with rapid and heavy growth at 37 degrees C. No growth occurs at 42 degrees C. This organism ferments glucose but does not hydrolyze urea or arginine and has an absolute requirement for sterol from growth. Strain UCMF(T) does not hemagglutinate or hemadsorb chicken erythrocytes. The genome size is 870 kbp, and the guanine-plus-cytosine content is 31 mol%. Sequence analysis of the 16S rRNA gene demonstrated that this organism is unique and has not been described previously. Serological analysis confirmed that strain UCMF(T) is distinct from all previously identified Mycoplasma, Acholeplasma, Spiroplasma, Entomoplasma, and Mesoplasma species. This organism represents a new species, for which we propose the name Mycoplasma sturni. Strain UCMF (= ATCC 51945) is the type strain of M. sturni sp. nov.

Immunocytochemical evidence of Listeria, Escherichia coli, and Streptococcus antigens in Crohn's disease

BACKGROUND/AIMS

Infectious agents have long been suspected of playing a role in the initiation of Crohn's disease. The objective of this study was to search for likely microbial agents in diseased tissues using immunocytochemical techniques.

METHODS

Intestines and mesenteric lymph node specimens of 21 patients from two French families with a high frequency of Crohn's disease and from Connecticut were studied. The microbial agents searched for included Bacteroides vulgatus, Borrelia burgdorferi, Escherichia coli, Listeria monocytogenes, Streptococcus spp., bovine viral diarrhea virus, influenza A virus, measles virus, parainfluenza virus, and respiratory syncytial virus.

RESULTS

Seventy-five percent of the patients with Crohn's disease (12 of 16) were positively labeled with the antibody to Listeria. Macrophages and giant cells immunolabeled for this antigen were distributed underneath ulcers, along fissures, around abscesses, within the lamina propria, in granulomas, and in the germinal centers of mesenteric lymph nodes. In addition, 57% (12 of 21) of the cases contained the E. coli antigen, and 44% (7 of 16) contained the streptococcal antigen. The immunolabeling for the latter two agents also occurred within macrophages and giant cells, distributed in a pattern similar to that of Listeria antigen.

CONCLUSIONS

The results suggest that Listeria spp., E. coli, and streptococci, but not measles virus, play a role in the pathogenesis of Crohn's disease.

Morphologic considerations in the interpretation of gastrointestinal disorders

Misinterpretations of gastrointestinal alterations can be reduced or eliminated by avoiding sampling/labeling errors, reducing artifact, and gaining familiarity with normal variations for the species under study. The errant thrust of the gastroscopic biopsy forceps can yield mucosa resembling atrophic gastritis; ileal villi taken for jejunal erroneously lead to consideration of sprue-like disorder. Reduction of the postmortem delay prior to fixation is critical for avoiding artifact. Villous epithelial cells separate from basement membrane within 5 to 10 minutes. Flushing saline, water, or fixative through unopened intestine causes intolerable damage to epithelium and villi. The thin-walled intestines of small laboratory species may be fixed unopened, but without dissection gross lesions are overlooked. Osmolarity of the fixative is important for preserving normal shapes of villi. Smooth muscle of the muscularis and villi of the dog contracts vigorously after euthanasia and immediate fixation. Optimum preservation may be had by applying iso-osmolar neutral buffered fixatives to intestinal segments which have been opened, stretched slightly, and pinned to cardboard or styrofoam. The villous height:crypt depth ratios vary among species and among intestinal segments. Shapes vary as well, ileal villi of many species appearing short and Christmas-tree- or thumb-shaped. Dilated lacteals occur occasionally in normal villi. The goblet cell population increases aborally, while the lymphocytic-plasmacytic population of the core increases with age. Eosinophils are a normal component in several species; globule leukocytes are common in others. Mast cells of the villi will be overlooked unless tissues are fixed in Carnoy's solution and stained with Astra or Alcian blue.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevalence of paratuberculosis in culled New England cattle

The prevalence of bovine paratuberculosis in New England was determined to be 18% based on a random survey of abattoir cattle. Six tissues from each of 100 animals were examined by histologic and bacteriologic methods. The cecal lymph node and the ileocecal valve yielded positive cultures most frequently, but isolations were also made from liver, tonsil, colon, and ileum. On the basis of the prevalence data, the economic significance of paratuberculosis to the New England dairy industry was estimated in excess of +15.4 million annually. Field studies identified 25 infected herds in New England. One of the infected herds from Connecticut was sold at public auction, an act which resulted in the dissemination of 95 potentially infected cattle to 28 farms in 8 different states.

Mucoid enteritis of rabbits. Comparison to cholera and cystic fibrosis

Fourteen cases of spontaneous mucoid enteritis, five cases that occurred after transmission of material from natural cases, and 13 control animals were studied to define disease characteristics and lesions. Prominent clinical features included diarrhea with passage of mucus, polydipsia, crouched stance, distended abdomen, succussion splash, and subnormal temperature. Transmission of the disease was equivocally successful. Rabbits with mucoid enteritis had moderate leukocytosis, hyperglycemia, azotemia, serum globulin alterations, and electrolyte imbalance. Autopsy consistently revealed distended stomach, fluid-filled small bowel, impacted cecum, and mucus-filled colon. In the small intestine there was mucus-cell hyperplasia and in the colon mucous casts, glandular dilatation, and depletion of acidic mucus. The small-bowel changes in mucoid enteritis are similar to those in enterotoxin-induced secretory diarrheas, and the excessive discharge of mucus is comparable to that of cystic fibrosis.