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Biomedical subjects

J Ahlqvist

Publications and source records attributed to J Ahlqvist.

At least 37 records · Page 2Linked to original sources
PubMed1994

High hydrostatic pressures in traumatic joints require elevated synovial capillary pressure probably associated with arteriolar vasodilatation.

Three out of the four Starling pressures were determined at arthroscopy of traumatic effusions of the knee. The range of the joint fluid hydrostatic pressure Pjoint was 5-83 cmH2O (0.5-8.1 kPa, 4-61 mmHg), that of the colloid osmotic pressure difference COPplasma-COPjoint 0-21.7 cmH2O. In 11 of 15 cases the sum Pjoint+COP difference exceeded 32.6 cmH2O (3.19 kPa, 24 mmHg), a high estimate of average capillary pressure at the level of the heart. The number of 'exceeding' cases was 8/15 if only 80% of the COP difference was considered effective. Pjoint and the COP difference oppose filtration of fluid from plasma into joints, indicating that mean capillary pressure, the only Starling pressure not determined, was elevated unless the effusions were being resorbed back into the blood. The findings can be explained by tamponade compensated by arteriolar vasodilatation, suspected to be metabolically mediated.

Adolescent↗
PubMed1993

A technique for the accurate administration of corticosteroids in the temporomandibular joint.

A new technique for intra-articular injection of a corticosteroid in the temporomandibular joint (TMJ) is presented. The corticosteroid is mixed with contrast medium and the administration visualized and controlled using fluoroscopy. When superior and inferior joint spaces have been filled and the soft tissues of the joint have been identified in the fluoroscopic image, additional corticosteroid can be administered to selected sites within the TMJ.

Adrenal Cortex Hormones↗
PubMed1990

Osseointegrated implants in edentulous jaws: a 2-year longitudinal study.

Osseointegrated implants in 50 edentulous jaws were studied during a 2-year observation period. The implant survival rate was 89% in the maxillae and 97% in the mandibles. The marginal bone loss averaged 1.7 mm in the maxillae and 1.1 mm in the mandibles. Most of this bone loss occurred during the first year. The bone loss was greater in jaws with a preoperatively minor resorption of the alveolar ridge than in those with moderate or advanced resorption. The bone loss was also greater at the medially positioned implants than at those more posterior.

Adult↗
PubMed1989

Colloid osmotic and hydrostatic pressures and energy metabolism in high-protein joint swelling. A preliminary study of traumatic effusions of the knee.

In 10 patients referred to arthroscopy with traumatic effusions of the knee, the protein concentration of the synovial fluid (SF) correlated to its colloid osmotic pressure (pi SF). The pi SF did not correlate to the poorly determined hydrostatic pressure (PSF) in extended or slightly flexed joints or to the SF volume (VSF). SF hypoxia correlated to pi SF and to the number of intra-articular erythrocytes, but not to the determined PSF or VSF. SF hypoxia correlated to increase in lactate and decrease in pH, fitting enhanced anaerobic glycolysis. In addition, SF erythrocyte counts correlated to lactate increase. During a 5-min period of high PSF induced by flexion, the PSF decreased, and even more markedly so after the joints had been rinsed with saline. The results suggest that rinsing of joints in order to lower the pi SF and to remove erythrocytes is of benefit in cases of traumatic effusion.

Cell Count↗
PubMed1988

A physiological approach to the pathogenesis of rheumatoid and other high-protein arthropathies.

In many types of arthropathy the synovial fluid (SF) oxygen tension and glucose levels often are low and associated with lactic acidosis which, unless joints are insensitive to the lack of fuel and oxygen, must contribute to joint damage. To such hypoxic-ischaemic changes can contribute quite a number of rheological and other mechanisms and synovial necroses, but also tamponade due to increased SF hydrostatic pressure caused by colloid osmotic forces (pi) in SF with a high protein concentration. pi in SF can be increased by numerous mechanisms, many of which are active in patients with rheumatoid and other arthropathies. The present compilation shows that the above in a dynamic fashion can be covered by equations elaborated by physiologists.

Arthritis↗
PubMed1988

Rheumatoid factors and physiology of synovial joints.

Analysis of rheumatoid factor (RF) effects according to physiological principles suggests that RF activity may decrease joint swelling by (i) decreasing synovial fluid (SF) colloid osmotic pressure, by increasing plasma viscosity and thereby decreasing (ii) fluid escape from the plasma and (iii) convective flux of proteins into joints, and by decreasing (iv) diffusion of proteins from capillaries (et cetera?). RF complexes raising whole blood viscosity might (v) decrease blood flow. A more significant cause of SF hypoxia and lactic acidosis may be tamponade of synovial circulation created by swelling-induced high SF hydrostatic pressures. Increase of non-RF IgG or monomeric IgM and possibly agammaglobulinaemia could contribute to swelling more strongly than RF's.

Arthritis, Rheumatoid↗
PubMed1986

C-reactive protein compared with white blood cell count and erythrocyte sedimentation rate in the diagnosis of acute appendicitis in children.

Acute abdominal symptoms in 162 children were investigated with rapidly quantified C-reactive protein (CRP), white blood cell (WBC) count and erythrocyte sedimentation rate (ESR) as laboratory parameters. When the symptoms had been present for at least 12 hours, the CRP level was greater than 10 mg/l in 72% of cases with histologic evidence of appendicitis, while leukocytosis (WBC greater than 15 000/mm3) and raised ESR (greater than 20 mm/l h) were found in 58% and 51%, respectively. If appendicitis had progressed to gangrenous stage, however, CRP alone was capable of identifying 83% of cases, while 76% had leukocytosis and 60% elevated ESR. When perforation had occurred there was greatly increased CRP and invariably leukocytosis, but elevated ESR in only 60%. With the combination CRP and WBC count (using rise in one or both), 88% of all appendicitis cases could be identified, and at least 96% of those with gangrene or perforation. The predictive value of combined positive CRP and WBC tests was not less than 93%.

Acute Disease↗
PubMed1985

Multifactorial pathogenesis: ought we to classify disease or treat the individual's causes of disease?

Added to the uniqueness of most of us imparted by HLA, our individual differences in the expression of other genetic traits, foetal period steroid imprints on brain and other functions, and regulators shared by body and mind indicate that each one of us (except most monozygotic twins) is born as a unique individual whole (I). Mechanisms suspected to be contributing ones in classified synovitides appear to correspond to individually exaggerated or depressed modes of response by physiological mechanisms linked to our unique individual wholes (II). If we upgrade the importance of influences of combinations of 'contributing' mechanisms, the importance of the alleged unknown fundamental causes of these diseases diminishes (III). This broad interpretation of 'multifactorial pathogenesis' can probably be applied to many common types of disease (IV), implying that disease classifications may poorly reflect the individual's causes of disease (V). There is reason to challenge modern concepts about disease (VI).

Arthritis, Rheumatoid↗
PubMed1985

Decreased red cell deformability and vascular obstruction in falciparum malaria illustrated by a fatal case.

The autopsy findings in a case of falciparum malaria suggested that rheological mechanisms, above all decreased deformability of red cells, might have been the main cause of capillary obstruction. This mechanism had been assumed to be involved already in 1972, and red cells containing mature parasites have recently been shown to lack deformability. This may explain why severe cases have recovered after blood exchange.

Blood Viscosity↗
PubMed1985

On the structural and physiological basis of the influence of exercise, movement and immobilization in inflammatory joint diseases.

In inflammatory joint diseases the protein concentration often is high in the synovial fluid and, in rheumatoid arthritis at least, probably also in the extra-articular connective tissue. This alters the Starling equilibrium. Peculiarities of the circulation of blood and lymph in articular units and basic physiological principles might explain not only why this readily manifests as joint effusions, but also the influence of exercise, movement, immobilization and posture on the activity of non-bacterial synovitides.

Animals↗
PubMed1984

A hypothesis on the pathogenesis of rheumatoid and other non-specific synovitides. IV A. The possible intermediate role of local hypoxia and metabolic alterations.

According to the original hypothesis, synovial tissue (ST) oedema and synovial fluid (SF) volume increase contribute to local hypoxia and metabolic alterations and to inflammation (A 1). Studies on biochemical mechanisms (A 2) in synovitides show that the SF volume correlates to SF hypoxia that correlates to lactate increase, acidosis and to some decrease in glucose. Normal ST produces lactate by glycolytic and pentose phosphate pathway activity, both, as well as the normally low oxygen utilization, being increased in synovitides . In ST very little carbohydrate seems to pass directly into the citric acid cycle and oxidation of fat may be involved, but it is not known if the fat is carried to ST by the blood or if it is synthetized locally (B). ST oedema and effusions may be most important as causes of local hypoxia (C). Acidosis alters physico-chemical properties of proteins, possibly changing their chemotactic and antigenic qualities, etc. Hypoxia and fuel supply might be related to fibroblast, macrophage and neutrophil reactions, and, in view of the high metabolic demands of villi, they may contribute to, e.g., ST necroses, and to erosions (D). I shall summarize some essentials of my present views on the pathogenesis (E 1 a) and causes in single cases (E 3 b) of synovitis, and comment on two other new hypotheses on rheumatoid arthritis (E 2) and on therapeutic (E 4) and other implications of this concept (E).

Acidosis↗
PubMed1984

BCG vaccination as a cause of osteomyelitis and subcutaneous abscess.

Ten patients with osteomyelitis and three with a subcutaneous abscess, all caused by BCG vaccination, are described. All patients were less than 3 years old and had as newborns been vaccinated intracutaneously in the left gluteal or hip area. Pain, limping, or a slightly tender subcutaneous induration were the primary symptoms. The sites of predilection of osteomyelitis were the metaphysis or epiphysis of the femur, these being affected in five out of 10 cases. All three subcutaneous abscesses were in the thoracic region. Prolonged (up to 30 months) combined tuberculostatic medication, in addition to appropriate surgical procedures, resulted in healing, but two cases of arthritis and two of secondary abscesses developed. In addition, sequestrectomy and two late operations, for coxa valga and hip subluxation, were deemed to be necessary. Radiographs showed femoral overgrowth of up to 1 cm in two symptomless patients three to seven years after the first discharge. We conclude that the benefits of BCG vaccination should be weighed against the risk of complications, especially in countries with a low incidence of tuberculosis.

Abscess↗
PubMed1982

Fungal arthritis simulating juvenile rheumatoid arthritis.

Petriellidium boydii is often isolated from maduromycosis but has recently been associated with arthritis. A previously healthy 6-year-old boy developed chronic purulent arthritis of the knee after a bicycle accident. Culture of aspirate grew no pathogens and antibiotic treatment had no effect. Culture of synovial fluid grew P boydii, which responded initially to amphotericin but reappeared after six months. Subsequent treatment with miconazole was stopped after development of haematuria. The fungus was sensitive to ketoconazole, and treatment with this drug cured the infection. With the introduction of ketoconazole it is of practical importance to recognise fungal infections.

Antifungal Agents↗