New spiral bacterium in gastric mucosa

A new spiral bacterium, distinct from Campylobacter pylori, was found in the gastric mucosa of six patients with gastrointestinal symptoms. All patients had chronic active type B gastritis and four had oesophagitis. Culture and microscopy for C pylori infection was negative. These unculturable spiral organisms were probably an incidental finding in patients presenting for upper gastrointestinal endoscopy, but it is not possible to say from this small series whether these organisms cause chronic active gastritis. The organism is helical, 3.5-7.5 microns long and 0.9 micron in diameter with truncated ends flattened at the tips, and up to 12 sheathed flagella 28 nm in diameter at each pole. It is proposed that this spiral bacterium should be called "Gastrospirillum hominis Gen.nov., Sp.nov."

Light- and electron-microscopic studies on multinucleated giant cells in sarcoid granuloma: new aspects of asteroid and Schaumann bodies

Ultrastructural studies using transmission, analytical, electron, and light microscopy were performed on epithelioid granulomata in 4 lymph nodes from a case of sarcoidosis, emphasizing the organization of asteroid and Schaumann bodies in multinucleated giant cells and the deposition of chemical elements. Serial sectioning at semithin level showed a single multinucleated giant cell can contain up to 4 asteroid and 1 Schaumann body. Microtubules and centrioles were not found in asteroid bodies, although a centriolar field was present in 1 giant cell close to the plasma membrane, completely unrelated to the asteroid body. In 1 asteroid body, tubulelike structures were observed in a focus showing filament dissociation. A principal ultrastructural finding is intimate envelopment of radiating filamentous arms of the asteroid body by myelinoid membranes, extensive forms of which are also present between the arms. Elemental analysis revealed a definite peak of calcium and a probable phosphorus peak in relation to the asteroid body and associated myelinoid membranes. Calcium and phosphorus with smaller quantities of aluminum and iron were found in Schaumann bodies. Our studies indicate that organization of the asteroid body is more complex than hitherto described, independent of the centriolar and microtubular systems. Evidence for the possible developmental pathway of the Schaumann body is provided by morphological changes within myelinoid figures intimately related to the asteroid body.

Interaction between mast cells and perineurial fibroblasts in neurofibroma. New insights into mast cell function

Transmission electron microscopy was performed on seven neurofibromata to study the relationship between the frequently occurring mast cells and the other cell types present in the tumour. Intimate association was observed between mast cells and perineurial fibroblasts, but not between mast cells and Schwann cells. At the contact interface between mast cells and perineurial fibroblasts, numerous vesicle-like structures were observed with corresponding endocytotic vesicles in the fibroblast plasma membrane. The authors regard this close morphological relationship as in vivo evidence for a possible role of mast cells in fibroblast metabolism, a conclusion which has already been drawn from in vitro studies, but until now inadequately supported by observations in vivo.

Microsporidiosis in a British patient with AIDS

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Immunologic competence of hemodialysis patients following withdrawal of vitamin C supplement

Twelve stable nondiabetic patients on chronic hemodialysis were studied for their immunobiologic competence while receiving vitamin C supplement and 1-2 months following its withdrawal. These subjects, on prescribed diets, were checked for their food intake at the beginning of the study and at 1-month intervals thereafter. Immunological parameters tested were: (1) plasma vitamin C levels; (2) number of mononuclear cells isolated from blood and their vitamin C contents; (3) lymphocyte blastogenic response to mitogens; (4) leukocyte metabolic functions in presence of endotoxin by nitroblue tetrazolium reduction test, and (5) delayed hypersensitivity to skin-testing antigens, e.g. Candida and mumps antigens and purified protein derivative. Patients on vitamin C had significantly higher plasma ascorbic acid levels compared to normal healthy subjects. These decreased to low normal levels 1 month following withdrawal of the supplement and stayed comparable thereafter, up to 12 months of the study period. Ascorbic acid contents in the isolated mononuclear cells remained unchanged in patients on or off vitamin C. The number of blood mononuclear cells isolated and mitogenic responses to concanavalin A and phytohemagglutinin did not change following withdrawal of vitamin C supplement. All patients had positive delayed hypersensitivity to Candida, 60% to mumps and all were unresponsive to purified protein derivative. Leukocyte metabolic functions by nitroblue tetrazolium reduction test were higher in patients on vitamin C than when off, but this was not statistically significant. Vitamin C supplement is not necessary in hemodialysis patients when they are on an adequate diet.

Systemic kappa light chain deposition and amyloidosis in multiple myeloma: novel morphological observations

Light and transmission electron microscopic studies as well as immunohistochemical investigations were performed on a case of multiple myeloma in a 40-year-old female with systemic kappa light chain deposition. The latter took the form of extensive deposits in the liver, spleen and bone marrow. Amyloid was not found in these deposits, although it was present in the wall of branches of the portal vein. Conversely, amyloid but not light chain deposition was found in the tongue, synovial membrane from the knee and myocardium. The kidney was the only organ to show both amyloid and light chain deposits intimately associated with each other in and around tubules and collecting ducts. Ultrastructurally the light chain deposits were seen to be biphasic, having two granular components of different electron density. In the spleen and bone marrow, but not in the liver, the kappa light chain deposits were surrounded by multinucleated giant cells. This is the first report of light chain deposition disease associated with a foreign body type of giant cell reaction. The morphological variability of organ involvement suggests that the molecular structure and conformation of the deposited light chains are heterogeneous and may reflect a broad spectrum of metabolism of these deposits in various organs.

Enteric coronavirus in symptomless homosexuals

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The reliability of activated partial thromboplastin time methods and the relationship to lipid composition and ultrastructure

Wide variations in procoagulant properties, lipid composition and ultrastructure of five commonly used APTT methods have been demonstrated. Performance of the methods with a range of coagulation abnormalities has been ranked. Most of the reagents obtained a high score with one or more defects, but a low score with others. A consistent good ranking throughout was only observed with one reagent. The number of significant correlations between the reagents' procoagulant activities and lipid content confirms the view that the performance of an APTT method is largely dependent upon its lipid composition. Marked differences in concentration and distribution of phospholipids, fatty acids and neutral lipids were evident. The importance of the concentration of phosphatidyl serine in regulating the procoagulant activity of an APTT method has been demonstrated. Electron microscopy provides evidence of the contrasting composition of the reagents from the more discrete uniform liposomes present in the more reliable reagents, to more ill-defined components present in those reagents which performed less well. The study highlights the need for standardisation of the APTT.

Cryptosporidium species a "new" human pathogen

Publications describing aspects of the coccidian protozoan parasite Cryptosporidium, increased greatly during 1983 and 1984 as a result of not only increasing veterinary interest but also in the role of the parasite in the newly recognised acquired immune deficiency syndrome (AIDS). The reports reflected widespread collaboration, not only between clinicians, microbiologists, and histopathologists, but also between veterinary and human health care workers. Cryptosporidium was first described in mice in 1907 and subsequently in various other species; it was not described in man until 1976. Several likely putative species have been described, but there is probably little host specificity. Experimental and clinical studies have greatly increased the knowledge about the organism's biology. The parasite undergoes its complete life cycle within the intestine, although it may occasionally occur in other sites. The main symptom produced is a non-inflammatory diarrhoea, which, in patients with AIDS and children in Third World countries, may be life threatening: even in immunocompetent subjects this symptom is usually protracted. Attempts to find effective chemotherapeutic agents have been unsuccessful. Epidemiologically the infection was thought to be zoonotic in origin, but there is increasing evidence of person to person transmission. Diagnosis has depended upon histological examination, but simple methods of detection have now been described: more invasive methods need no longer be used. The parasite, which is found more commonly in children, occurs in about 2% of faecal specimens examined and seems to be closely associated with production of symptoms. A serological response has been shown. Much remains to be learned about its epidemiology and pathogenic mechanisms, while the expected increase in incidence of AIDS makes an effective form of treatment essential.

An ultrastructural study of the gastric campylobacter-like organism 'Campylobacter pyloridis'

Microaerophilic spiral organisms may be isolated frequently from samples of gastric mucus taken from patients undergoing gastroscopy. The ultrastructure of these gastric campylobacter-like organisms ('Campylobacter pyloridis') shows that they have greater affinities with Spirillum than with Campylobacter.

Micro-organisms in gastroenteritis

We present bacteriological and virological findings together with salient clinical features from a prospective study of 447 children aged under 2 years admitted to hospital with infectious gastroenteritis. Putative pathogenic micro-organisms were identified in the stools of 75% of these children. Eight identifiably distinct groups of viruses, found on electron microscopy and tissue culture were present in 67% of patients--rotavirus was detected most frequently. Pathogenic bacteria (salmonellas, shigellas, Escherichia coli, and Campylobacter jejuni--but excluding Clostridium difficile) were found in 16% only. Altogether 4 X 9% of 390 patients had gastroenteritis associated with Cl difficile toxin. The mean duration of diarrhoea was shortest in patients with identifiable virus, with rotavirus having a mean of 5 X 01 days, and was longest in patients with pathogenic bacteria in the stools (11 X 14 days). The finding of more than one type of virus did not seem to be associated with a significantly increased duration of diarrhoea. There are few clinical features which can be associated specifically with any particular micro-organism or groups of these. Multiple organism isolation was common, but the severity of the illness in those patients with at least two types of organism was not greater. Certain viruses, including the norwalk-like virus, known to be associated with outbreaks of gastroenteritis were found as frequently in a group of patients who did not have diarrhoea studied for comparison. Virus was still detectable in the stools of up to 40% of asymptomatic children on the day of discharge.

Food borne infection by a Norwalk like virus (small round structured virus)

Two outbreaks of gastrointestinal illness with identical symptoms occurred in parties attending banquets on consecutive evenings at a large hotel. The illness was typical of epidemic winter vomiting disease. Small round structured viruses resembling those seen in the Norwalk Ohio outbreak were identified by electron microscopy in stools of victims from one episode. One food handler was found to be excreting the virus, and there was evidence of a poor standard of hygiene in the kitchen. A food history analysis showed the illness to be significantly associated with eating cold cooked ham.

A new bacterial flagellar structure found in campylobacters

A previously unrecognized bacterial flagellar structure present in Campylobacter jejuni and Campylobacter fetus is described. The structure is located just below the insertion of the flagellar apparatus through the bacterial wall. It is disc shaped, approximately 100 nm in diameter and has eleven spokes radiating from a central hole. The function of this new structure and its possible importance in the taxonomy of campylobacters and other spiral micro-organisms are discussed.

Pneumocystis carinii: the continuing enigma

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Pneumocystis carinii pneumonia: a light microscopical and ultrastructural study

A case of Pneumocystis carinii pneumonia developing a patient with treated diffuse lymphocytic lymphoma is described. The electron microscopic features and life cycle of the organism are illustrated. The patient died twenty-four hours after the biopsy had been taken. Septrin appeared to have affected the trophozoite stage. Pneumocystis carinii appears to induce interstitial pulmonary oedema and fibrosis. A discussion of the role of electron microscopy in early diagnosis of the disease is presented.

Demonstration of papilloma virus particles in cervical and vaginal scrape material: a report of 10 cases

The finding of virus particles by transmission electron microscopy (TEM) in fixed cervical and vaginal scrape material and their identification as papilloma viruses by negative staining is described. The colposcopic, cytological, and histological appearances in a group of 10 patients in whom virus particles were seen are discussed and the possibly considered of an association between papilloma virus infection and the development of cervical intraepithelial neoplasia (CIN) and multifocal intraepithelial neoplasia of the female lower genital tract.

Detection of herpes-simplex viral genome in brain tissue

Herpes-simplex virus type (HSV-1) nucleic-acid sequences were detected by in-situ hybridisation in thin sections of brains from mice which had been inoculated 24 weeks previously with HSV-1. These mice were not ill, and infectious virus could not be recovered from them. HSV-1 sequences were also present in brain smears from 3 of 4 elderly patients who had died with chronic psychiatric illness and neuropathological changes but not in smears from 2 patients who had had acute psychotic episodes and minimum abnormal histology. Adenovirus type 7 nucleic-acid sequences were not detected in these human specimens.

Letter: Sand pneumoconiosis in an egyptian mummy

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