A transmission electron microscopic comparison of the articular surface of cartilage processed attached to bone and detached from bone.

The purpose of this study was to ascertain whether the surface asperities detected with the transmission electron microscope in shavings of young adult articular cartilage detached from bone reflect an in vivo condition or are artefacts. With this in view shavings of rabbit articular cartilage processed in the conventional manner were compared with pieces of cartilage attached to bone processed by a new method which we have evolved. An undulating surface and asperities up to about 0.3 micrometer deep were found in cartilage shavings processed in the conventional manner, but such asperities were not seen on cartilage processed attached to bone. We have therefore concluded that such asperities are artefactual and that they are engendered by cartilage curling. Cartilage processed attached to bone has an amazingly smooth surface; any so-called 'asperities' are less than 0.03 micrometer in depth and are confined to the surface coat which seems to be of a transient nature. On rare occasions, however, focal areas of roughening were found, where the asperities reached a depth of about 0.15 micrometer. Several past studies (reviewed in this paper) have shown that virtually all the asperities seen with the scanning electron microscope on the articular surface are artefacts of tissue processing. We have now shown that even most of the much smaller asperities seen with the transmission electron microscope are also artefacts. Therefore one has to conclude that the articular surface of young adults is remarkably smooth and that the surface asperities must be attributed to artefacts, ageing or pathological changes.

Uraniosomes produced in the synovial membrane by uranyl acetate.

Uranyl acetate was injected into the rabbit knee joint. This produced single-membrane-bound presumably lysosmal bodies (called 'uraniosomes') containing electron-dense crystals in Type A and Type B synovial intimal cells, subsynovial macrophages and lipocytes. Uranium deposits were also seen in the extracellular matrix. All uraniosomes and extracellular deposits analysed by electron-probe X-ray analysis were found to contain uranium, potassium and phosphorus. Traces of calcium and sulphur were also found in some of the uraniosomes and extracellular uranium deposits.

Amianthoid fibres in a chondrosarcoma.

Amianthoid fibres up to about 1000 nm thick were found in the matrix of a chondrosarcoma. Our findings support the idea that this is a degenerative change and that these fibres are probably formed by coalescence of collagen fibrils.

Immunogenetic aspects of nasopharyngeal carcinoma. V. Confirmation of a Chinese-related HLA profile (A2, Singapore 2) associated with an increased risk in Chinese for nasopharyngeal carcinoma.

Histocompatibility locus A typing of 43 Malaysian Chinese and 51 Hong Kong Chinese patients with nasopharyngeal carcinoma (NPC) confirmed the association between the occurrence of A2-Sin 2 and the increased risk for NPC that was previously demonstrated in Singapore Chinese. The results support the previous interpretation that the histocompatibility locus A genotype of importance in NPC predisposition is the A2-Sin 2 haplotype. The histocompatibility locus A-linked, genetically determined NPC risk is common to Asian Chinese from at least three geographic locations.

The surface of dog articular cartilage: a scanning electron microscope study.

The surface of dog articular cartilage attached to subchondral bone shows many humps on its surface when examined with the scanning electron microscope. The situation here contrasts with that in man and rabbit where large numbers of pits are seen of the surface. Such species variations cast doubts on the idea that pits and humps play a vital role in joint mechanics and lubrication. Ridges and undulations were not found in normal dog cartilage attached to bone, but complex systems of ridges did develop when the cartilage was cut or detached from bone.

The pattern of intestinal obstruction in Malaysia.

This is a review of 261 patients operated for 271 instances of mechanical intestinal obstruction over a 5-year period in a developing country in the tropics. The pattern of intestinal obstruction in Chinese is similar to that in Caucasians, where adhesions account for the largest number of cases. The occurrence in Malays, Indians, Pakistanis and Ceylonese is similar to that in other developing communities where external hernia is commonest while adhesive or tumour obstruction is rare; however, these racial groups do not exhibit the high incidence of intussusception and volvulus found in Africa and India. The operative mortality was 13-9 per cent, which is comparable to that in Western series. The major adverse factors in intestinal obstruction, i.e. extremes of age, associated disease, gangrenous bowel, large bowel obstruction and malignancy, were confirmed. Fluid and electrolyte imbalance was frequent, as in other tropical series, but with intensive preoperative correction it was not an important adverse factor.

Ultrastructure of the haemophilic synovial membrane and electron-probe X-ray analysis of haemosiderin.

An ultrastructural study of the haemophilic synovial membrane revealed the presence of solitary siderosomes, compound siderosomes and a peppering of the cell cytoplasm with electron-dense particles. These changes were found in synovial intimal cells, subsynovial macrophages and fibroblasts. Electron-probe X-ray analysis of siderosomes revealed the presence of iron and traces of phosphorus. On the basis of previous and present studies it is postulated that haemosiderin is essentially a condensate of hydrated ferric oxide and that a variable amount of phospholipid material lies in company with it in the siderosome.

Experimental production of ridges on rabbit articular cartilage: a scanning electron microscope study.

The surface of normal rabbit articular cartilage attached to subchondral bone has a pitted appearance when examined with the scanning electron microsope. It is thought that these pits are similar to those seen in human cartilage and that they reflect the presence of underlying chondrocytes and lacunae, shrunken by preparative procedures. Ridges or undulations were not seen on the normal articular surface with the scanning electron microscope but complex systems of coarse and fine ridges were produced when cartilage was damaged by cutting, by making a hole in it or by detaching it from subchondral bone. Humps or mound-like elevations also developed in some instances when cartilage was damaged by cutting or by making a hole in its substance.

Emergency Surgery for Bleeding Peptic Ulcer and Erosive Gastritis - A study of 124 cases.

No abstract available.

Gastric Carcinoma - A review of 114 cases.

No abstract available.

Physiological activity in mediastinal teratomata.

The clinical details of two patients with benign mediastinal teratomata are presented. Both patients developed inflammation of the root of the neck, the first after a small dose of radiotherapy and the second after a larger dose of radiotherapy and exploration of the thoracic inlet. In both cases, exploration of the inflamed area was followed by persistent discharge of fluid which was sterile on culture. In the first case, this was found to have a high cholesterol, lipid, and amylase content. In both cases, a benign mixed teratoma, with contents including intestinal epithelium and pancreatic tissue, was removed at thoracotomy. The suggestion is made that leakage of digestive enzymes from pancreatic, intestinal or salivary tissue may be a cause of inflammation in and around teratomata, especially after surgical exploration. Early thoracotomy is advised when the condition is recognized.

Successful repair of a penetrating wound of the thoracic aorta.

Penetrating wounds of the aorta are not necessarily fatal. A successfully managed patient with a stab wound of the ascending aorta is reported, and some problems of management associated with such injuries are discussed.

Oesophagobronchial fistual presenting in the adult.

A case of congenital oesophagobronchial fistula presenting in adult life and treated successfully by surgical excision is reported. The most unusual feature is its late presentation and high origin.