Search PubMed⌕ Search

Biomedical subjects

M de Silva

Publications and source records attributed to M de Silva.

At least 73 records · Page 4Linked to original sources
PubMed1985

Purification of a metalloproteinase inhibitor from human rheumatoid synovial fluid.

A metalloproteinase inhibitor present in human rheumatoid synovial fluid was purified by a combination of heparin-Sepharose chromatography, concanavalin A-Sepharose chromatography, ion-exchange chromatography and gel filtration. The Mr of the purified inhibitor was 28000 by SDS/polyacrylamide-gel electrophoresis and 30000 by gel filtration. The inhibitor blocked the activity of the metalloproteinases collagenase, gelatinase and proteoglycanase, but not thermolysin or bacterial collagenase. The serine proteinase trypsin was not inhibited. The inhibitory activity was lost after treatment with trypsin (0.5 micrograms/ml) at 37 degrees C for 30 min, 4-aminophenylmercuric acetate (1 mM) at 37 degrees C for 3 h, after incubation for 30 min at 90 degrees C and by reduction and alkylation. These properties suggest that the inhibitor closely resembles the tissue inhibitor of metalloproteinases ('TIMP') recently purified from connective-tissue culture medium.

Arthritis, Rheumatoid↗
PubMed1985

Sacral chondromyxoid fibroma.

A 15-year-old girl with a limp and weakness and wasting of the left leg, was found to have a large chondromyxoid fibroma of the sacrum. The lesion presented difficulties in diagnosis because of its unusual site, neurological presentation, large size and extensive extension into the soft tissues of the pelvis and buttock.

Adolescent↗
PubMed1985

Failure of passively administered anti-Rh to prevent secondary Rh responses.

Rh-negative women, immunized to Rh by previous pregnancies, with only low concentrations of IgG anti-Rh(D) in their plasma were assigned at random to test and control groups (7 subjects in each group). Both groups were challenged with an intravenous injection of 0.28 ml of Rh-positive red cells; in addition, the test group received 500 micrograms anti-Rh intramuscularly. 2 weeks after the injections, all subjects showed an increase in plasma anti-Rh concentration; levels in test and control groups were similar. It is concluded that in Rh-immunized subjects with low levels of IgG anti-Rh a secondary response to Rh cannot be prevented by giving passively administered anti-Rh with the red cells.

Female↗
PubMed1985

Preoperative intraincisional cefamandole reduces wound infection and postoperative inpatient stay in upper abdominal surgery.

The use of preoperative intraincisional (POII) single dose antibiotic prophylaxis has the advantage of providing extremely high concentrations of antibiotic along all layers of the wound, whilst achieving adequate systemic concentrations throughout the operation. In a single blind controlled trial, 250 patients undergoing upper abdominal surgery were randomised to receive POII cefamandole (2g) or to act as control. There was one wound infection in the POII group compared with 18 in the control group (P less than 0.001). Hospital stay was reduced by an average of one day (P less than 0.02) in the antibiotic treated group.

Abdomen↗
PubMed1984

Metalloproteinases and collagenase inhibitors in rheumatoid synovial fluid.

The levels of metalloproteinases and metalloproteinase inhibitors were measured in rheumatoid synovial fluid. Reliable estimates of total enzyme and inhibitor levels in the synovial fluids were obtained only after hyaluronidase treatment and gel filtration. Three latent metalloproteinases were found which, after activation, degraded collagen, proteoglycan, and gelatin. These enzymes closely resembled the metalloproteinases secreted into connective tissue culture medium. In addition to alpha 2 macroglobulin, an Mr 30,000 collagenase inhibitor was detected which closely resembled the tissue inhibitor of metalloproteinase found in tissue culture medium.

Arthritis, Rheumatoid↗
PubMed1984

Complete cartilage-ring tracheal stenosis associated with anomalous left pulmonary artery: the ring-sling complex.

The persistent high mortality in infants with pulmonary artery "sling" (retrotracheal anomalous left pulmonary artery) is primarily due to the coexistence in such patients of long-segment tracheal stenosis due to complete cartilage rings. Five such patients are reported. Airway studies (by filtered high-kV radiography, bronchography, and/or CT) showed low carina, horizontal equal-length right and left mainstem bronchi, and long-segment tracheal stenosis. The length of the stenosis far exceeded the contact with the pulmonary sling. The suggested term "ring-sling complex" for such patients correctly places emphasis on detection of the tracheal malformation, which currently has no satisfactory surgical treatment.

Bronchography↗
PubMed1983

Experience with bucrylate (isobutyl-2-cyanoacrylate) embolization of cerebral arteriovenous malformations during surgery.

The clinical experience with five patients selected for embolization of cerebral arteriovenous malformations with bucrylate (isobutyl-2-cyanoacrylate) during surgery is described. Bucrylate embolization was used to obliterate one arteriovenous malformation with a dominant nutrient arterial network, and to facilitate surgical resection in two other cases. The extent of the embolization in one of these cases was limited because of segmental perfusion of the AVM nidus by different nutrient arteries. Histological examination of this arteriovenous malformation, resected 56 days after embolization, suggested bucrylate has minimal histotoxicity. Two arteriovenous malformations were found at operation to be unsuitable for embolization because of technical problems with access and exposure of nutrient arteries, and also because of vagaries in the angiographic data before surgery. In two cases, rapid polymerization of bucrylate resulted in gluing of the injection catheters into the arterial lumen. Two patients experienced transient postoperative neurological deficits after bucrylate embolization. Because of the potential hazards of the technique, direct bucrylate embolization of cerebral arteriovenous malformations should only be considered for those lesions felt unsuitable for direct microsurgical excision, and where facilities exist for recording angiographic data before surgery.

Adult↗
PubMed1982

Primary amoebic (Naegleria) meningoencephalitis.

The computed tomographic (CT) appearance of a case of primary meningoencephalitis due to the free living amoeba Naegleria fowleri is presented. The cisterns around and above the midbrain and the subarachnoid spaces were obliterated on precontrast CT. Marked enhancement in these regions was seen after intravenous contrast medium administration. The sulci and adjacent grey matter were also strongly enhanced. The ventricular size was normal. Pathological findings were those of arachnoiditis and invasion of the leptomeninges and brain substance by amoebae, especially at the base of the brain and cerebellum.

Amebiasis↗
PubMed1982

Intussusception on small bowel examinations in children.

Six children in whom an intussusception was diagnosed on a small bowel follow-through examination are presented. The radiographic signs of intussusception on such a study include: (1) a narrow channel of barium representing the compressed lumen of the intussusceptum, (2) a soft-tissue mass on either side of this channel due to hypertrophy and edema of the walls of the intussuceptum and intussuscipiens, (3) a coil spring appearance around the narrow channel, and (4) a mass lesion at the distal end of the narrow channel. Not all of these signs are present in each case. Intussusception is a dynamic process and the value of delayed films and frequent fluoroscopy during small bowel follow-through studies in these cases is stressed. All six cases had a demonstrable lesion as a lead point. Jejunal intussusceptions are usually caused by bening lesions--malignancy being found almost exclusively in distal intussusceptions.

Adolescent↗
PubMed1981

Bilateral optic nerve hypoplasia.

In the past 10 years, 15 children with bilateral optic nerve hypoplasia have been studied at the Royal Alexandra Hospital for Children. There were 5 boys and 10 girls. Nine were first-born and they presented at a mean age of 5 months (range: 4 days to 25 months). Five presented with suspected blindness and 7 with abnormal eye movements (nystagmus or less commonly squint). The other 3 presented because of fits or developmental delay. Eight showed evidence of neural damage--microcephaly, seizures and/or abnormalities of tone. Four appeared to be of normal or near normal intelligence, 6 were mildly retarded and 5 severely so. Two patients had already died, one suddenly. Six of the 7 cases investigated in detail had evidence of hypothalamic pituitary dysfunction. Another one had a minimal hypothalamic abnormality. Four were severely growth retarded and 2 were receiving growth hormone replacement. Two males had micropenis and a girl had precocious puberty with partial diabetes insipidus. Neuroradiological investigations showed an absent septum pellucidum in only 5 cases. Five patients had other major CNS malformations. Five patients had normal CT scans; 3 of these 5 appeared of normal intelligence and all 5 had normal neurological examinations. Bilateral optic nerve hypoplasia is frequently associated with serious brain and endocrine abnormalities.

Brain↗
PubMed1979

Liposomes in arthritis: a new approach.

Intra-articular liposomal cortisol palmitate in a dose equivalent to 2 mg of cortisol produced a worthwhile therapeutic response in patients with rheumatoid arthritis. This may represent a valuable new approach to treatment.

Arthritis, Rheumatoid↗
PubMed1978

The radiology of neonatal necrotizing enterocolitis (NEC). A review of 47 cases and the literature.

The radiological findings in 47 neonates with necrotizing enterocolitis (NEC) are reviewed. The presence of nonspecific, generalized bowel dilatation is stressed as being an important sign in early diagnosis and the progress of the distribution of the dilated loops is important in evaluating progress of the disease process. It is thus the key to the radiology of NEC. Intramural gas and portal venous gas are not always related to the severity of the disease and their disappearance is not always related to clinical improvement. These signs are therefore poor prognostic indicators. Important radiological indications for surgery besides free intraperitoneal gas and free fluid include: 1. diminished bowel gas with asymmetric loops, and 2. persistent dilated loops. Because of the number of colonic strictures seen at our hospital we advise routine barium enemas (several weeks after the acute phase) in all infants who have had NEC. Following bowel resection contrast studies of both distal and proximal remaining bowel are essential to exclude further stricture formation prior to final reanastomosis.

Enterocolitis, Pseudomembranous↗