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Biomedical subjects

I Watt

Publications and source records attributed to I Watt.

At least 145 records · Page 8Linked to original sources
PubMed1986

Osteoclast-rich osteosarcoma.

Nine cases of primary osteoclast-rich osteosarcoma, an undifferentiated sarcoma with an overabundance of osteoclasts and a paucity of tumour osteoid, are reported. They comprise about 3% of all primary osteosarcomas and are histologically related to telangiectatic osteosarcoma, another undifferentiated tumour with abundant osteoclasts and scanty osteoid, perhaps being a predominantly solid variant of the latter. Many of the classical radiological features of an osteosarcoma are absent in these cases and differentiation from a benign lesion is sometimes difficult. Typically, an ill-defined margin surrounds a predominantly lytic lesion of the diaphysis or metaphysis of the femur or tibia of a young patient. A soft-tissue mass is not usually present and periosteal reaction is scanty.

Adolescent↗
PubMed1986

Arbovirus infections in several Ontario mammals, 1975-1980.

Serological studies for arboviruses were conducted on 725 animal sera collected in 22 Ontario townships between 1975 and 1980 including 44 coyote (Canis latrans), 277 red fox (Vulpes vulpes), 192 raccoon (Procyon lotor) and 212 striped skunk (Mephitis mephitis). Hemagglutination inhibition antibodies to two flaviviruses, namely St. Louis encephalitis and Powassan were found in 50% of coyote, 47% of skunk, 26% of fox and 10% of raccoon sera. Similarly, hemagglutination inhibition antibodies to a California serogroup virus, snowshoe hare, were found in 12% of fox, 7% of skunk, 7% of raccoon and 5% of coyote sera. No antibodies were detected to two alphavirus, namely eastern equine encephalitis and western equine encephalitis, antigens. This study affirms the endemic presence of Powassan and snowshoe hare virus and further delineates the scope of St. Louis encephalitis activity in Ontario.

Animals↗
PubMed1985

Palaeopathology of spinal osteophytosis, vertebral ankylosis, ankylosing spondylitis, and vertebral hyperostosis.

Five hundred and sixty intact skeletons and several thousand disarticulated vertebrae have been examined with special reference to spinal fusion. In period they ranged from a 21st dynasty Egyptian mummy to a mid-19th century skeleton. Osteophytes were found in about half of the specimens, as reported previously. Fifteen skeletons with extensive blocks of spinal fusion were also identified. Sacroiliitis was present in two, but the asymmetrical spinal disease and peripheral joint changes suggested Reiter's disease or psoriatic spondylitis rather than ankylosing spondylitis. The remaining 13 had typical features of Forrestier's disease, and extraspinal findings indicative of diffuse idiopathic skeletal hyperostosis (DISH) were also common. A review of the available literature suggests that many palaeopathological specimens previously reported as anklylosing spondylitis are examples of DISH or other seronegative spondylarthropathies. The antiquity and palaeopathology of AS needs reappraisal.

Adult↗
PubMed1985

The painful swollen sterno-clavicular joint.

Thirteen patients with isolated pain and swelling of a sterno-clavicular clavicular joint have been reviewed. Three groups were identified. Group 1 comprised four patients, all of whom had a short history of less than six weeks and suffered a pyarthrosis or malignant disease; group 2, four patients who were shown to have features of condensing osteitis of the clavicle (Cone et al, 1983); and group 3, five patients, had degenerative arthritis of a sterno-clavicular joint. The only difference between groups 2 and 3 were that patients in group 3 had a rather longer history, both articular surfaces were involved and showed a possible increase in the incidence of degenerative joint disease elsewhere. It is suggested that condensing osteitis is but a part of a spectrum of degenerative disease of the sterno-clavicular joints, akin to discogenic vertebral body sclerosis (McCarthy & Dorfman, 1982).

Adult↗
PubMed1984

Low incidence of calcium pyrophosphate dihydrate crystal deposition in rheumatoid arthritis, with modification of radiographic features in coexistent disease.

A negative correlation between rheumatoid arthritis (RA) and calcium pyrophosphate dihydrate (CPPD) crystal deposition was demonstrated in separate controlled radiographic and synovial fluid surveys of RA patients aged 55-75 years. Knee chondrocalcinosis was detected in 14% of 135 normal controls and 28% of 87 post-meniscectomy ("joint damage") controls (P less than 0.05), but only 3% of 100 RA and 75 osteoarthritis patients revealed CPPD crystals in 1% and 23%, respectively (P less than 0.01). Ten subjects with coexistent RA and CPPD deposition were also studied; 7 showed radiographic features atypical of RA, including patchy, asymmetric disease, retained bone density, prominent osteophytosis, well-corticated cysts, and paucity of progressive erosive disease. It is suggested that rheumatoid joint damage, unlike that in osteoarthritis, is not conducive to CPPD crystal formation. When RA and CPPD coexist, atypical radiographic features reflecting a hypertrophic reparative response may occur.

Aged↗
PubMed1984

Acute calcific periarthritis in a child.

We wish to present an account of a child who developed acute calcification in his thenar eminence to highlight the difficulty in differentiation between calcific periarthritis, acute infection, on clinical grounds. Calcific periarthritis is due to hydroxyapatite crystal deposits in bursae, tendons and ligaments (Bonavita 1980) with characteristic radiographic appearances of opacities of variable density and shape around joints (Hitchcock 1959). The condition was first described in the shoulder, by Duplay in 1870 (Sandstrom 1938) and this remains the most commonly affected site. The hip, elbow, wrist, knee and ankle may also be involved but involvement of the hand is uncommon. Involvement in this site was first described in 1924 by Cohen (Carroll 1955). The previously reported age span ranged from thirteen years upwards, with an average of forty-five years, both sexes being equally affected (Currey 1970, Hitchcock 1959, Bonavita 1980).

Calcinosis↗
PubMed1984

Apatite associated destructive arthritis.

Twelve patients, 11 women and one man, aged 66-83, with a distinctive type of destructive arthropathy are described. The principal joints affected were the shoulders (ten) and knees (seven). Clinical features included pain on use, large cool effusions, instability and rapid progression. Radiographs showed attrition of bone and cartilage with a paucity of reparative changes. Synovial fluids were viscous, with low cell counts, and stained positively for the presence of apatite-containing particles. Extensive calcific material was seen in the synovium of the four patients biopsied, and on the radiographs in seven. Most patients had some associated or preceding joint disorder. The literature on similar cases is reviewed, and the possible role of crystals and other aetiological factors is discussed. It is suggested that a characteristic form of large-joint atrophy can occur in elderly patients at a number of joint sites and in several different clinical settings.

Aged↗
PubMed1984

Mortality amongst multiple trauma patients admitted to an intensive therapy unit.

A retrospective review of 428 severely injured patients admitted to an intensive therapy unit between 1969 and 1982 was performed. The patients' primary injuries were assessed using the injury severity score (ISS), and subsequent complications using the complications impact index and sepsis score. Between 1969 and 1980 mortality fluctuated between 19% and 29% but rose to 47% (p less than 0.05) during 1981-82 in spite of an unchanged ISS. The increased mortality was confined to ventilated patients surviving more than 5 days from injury and was associated with multiple organ failure and severe infection. The rapid and sustained increase in mortality could not be explained by any obvious change in severity of injury or referral pattern. The only deliberate change in management related to the combination of analgesic/sedative drugs used in ventilated patients. During 1979 to 1982 mortality was 28% in patients given morphine with or without benzodiazepines and 77% in those given morphine and etomidate (p less than 0.0005). After discontinuation of the latter regimen (May 1983) and resumption of the former analgesic/sedative combination, mortality fell to 25% (p less than 0.005). Possible mechanisms leading to increased mortality include adrenocortical insufficiency or depth of anaesthesia.

Adolescent↗
PubMed1984

The effect of etomidate on adrenocortical function in dogs before and during hemorrhagic shock.

The effects of the hypnotic agent ethyl phenylethyl imidazole carboxylate (etomidate), on corticosteroidogenesis were studied in greyhound dogs during a 2-h period of anesthetic followed by a further 2 h of anesthetic combined with hemorrhage. Three groups of dogs were studied. The first, a control, received thiopentone and pentobartitone for induction and maintenance of anesthesia. A second control group received the chemically unrelated hypnotic preparation, althesin, after induction with thiopentone and pentobarbitone. In the first control group and the althesin-treated control group, changes in plasma ACTH and in plasma renin and angiotensin II concentrations were followed closely by changes in the levels of their respective dependent corticosteroids. A third experimental group received etomidate after induction of anesthesia with thiopentone and pentobarbitone. In these, in contrast, plasma levels of progesterone, 17 alpha-hydroxyprogesterone, corticosterone, cortisol, and aldosterone decreased during the experiment even failing to respond to massive rises in plasma ACTH concentration, renin, and angiotensin II levels after hemorrhage. However, the ability of 11-deoxycortisol and 11-deoxycorticosterone to respond was retained. These results suggest that etomidate inhibits corticosteroidogenesis directly, probably acting at more than one point in the biosynthetic pathway. It is suggested that it inhibits mitochondrial steroid hydroxylation (e.g. side chain cleavage, 11 beta-hydroxylation), but not 21-hydroxylation which occurs outside the mitochondrion.

Adrenal Cortex↗
PubMed1984

The radiological features of "solid" aneurysmal bone cysts.

The radiological features of nine solid aneurysmal bone cysts (ABC) have been reviewed. The appearances form a spectrum ranging from lesions indistinguishable from the classical ABC, to an osteolytic lesion with a wide zone of transition, cortical destruction and soft tissue extension. Over half the lesions reviewed fell into the latter category and all were situated in the axial skeleton. Discrimination between the more aggressive solid ABC, giant cell tumour and malignancy may be difficult. Demonstration of an expanded partial cortical rim by either conventional or computerised tomography suggests the diagnosis of solid aneurysmal bone cyst.

Adolescent↗