PubMed Health⌕ Search

Biomedical subjects

M J Inwood

Publications and source records attributed to M J Inwood.

17 recordsLinked to original sources
PubMed1990

Human recombinant DNA-derived antihemophilic factor (factor VIII) in the treatment of hemophilia A. recombinant Factor VIII Study Group.

BACKGROUND: Current treatment of hemophilia A, a hereditary disorder affecting approximately 1 in 10,000 males, relies on plasma-derived factor VIII concentrates. We tested the safety and efficacy of a recombinant factor VIII preparation for the treatment of this disorder. METHODS: We conducted the investigation in three stages: comparing the pharmacokinetics of plasma-derived and recombinant factor VIII, assessing the efficacy of recombinant factor VIII for home therapy, and assessing its efficacy for major surgical procedures and hemorrhage. A total of 107 subjects with hemophilia, 20 of whom had not been treated previously, enrolled in the investigation. RESULTS: The in vivo recovery and elimination half-lives of recombinant factor VIII equaled or exceeded those of plasma-derived factor VIII. Seventy-six subjects participated in a home-treatment program, using recombinant factor VIII for 69 to 807 days (median, 618); home diaries of 56 subjects treated for 5 months were analyzed. Of 540 bleeding episodes, 399 (73.9 percent) required only one treatment with recombinant factor VIII. The projected annual consumption of recombinant factor VIII was similar to that of plasma-derived factor VIII concentrate. Twenty-six subjects received recombinant factor VIII for 22 surgical procedures and 10 serious hemorrhages; hemostasis was excellent in all cases. De novo formation of inhibitors occurred in only 1 of 85 previously treated subjects. Inhibitor antibodies also developed in 6 of 21 children, 20 of whom had not previously been treated; 5 had low levels (less than or equal to 7.5 Bethesda units) despite continued treatment with recombinant factor VIII. There was no evidence of new formation of antibody to foreign proteins, and recombinant factor VIII was well tolerated. CONCLUSIONS: Recombinant factor VIII has biologic activity comparable to that of plasma factor VIII and is safe and efficacious for the treatment of hemophilia A.

Adult↗
PubMed1990

Sensitivity of the thrombin clotting time and activated partial thromboplastin time to low level of antithrombin III during heparin therapy.

The thrombin clotting time (TCT) has been used at our institution, along with the activated partial thromboplastin time (aPTT), for monitoring heparin therapy. We have observed that, in some patients, a discrepancy develops between the heparin levels predicted by the TCT and the aPTT with the TCT consistently predicting a lower heparin level than the aPTT. An inverse relationship was noted between the functional antithrombin III (AT-III) level and the magnitude of this discrepancy.

Antithrombin III↗
PubMed1990

Prescribing and dispensing practices for oral iron tablets: a Canadian experience.

The formulation of an oral iron tablet may influence its therapeutic efficacy in correcting iron deficiency. In order to determine the oral iron preparations patients in a Canadian urban center were receiving, a questionnaire was circulated to family physicians, internists, surgeons, and obstetrician-gynecologists to determine their prescribing practices. A survey of pharmacies in the city was also conducted to determine which brand of each iron salt (sulfate, gluconate, fumarate) they dispensed for a generic oral iron prescription. Most physicians (74 percent) chose ferrous sulfate as their drug of first choice. The majority of prescribers would not specifically request either enteric-coated/slow-release or nonenteric-coated preparations as first or second choices (71 and 64 percent, respectively). Enteric-coated or slow-release preparations were specified by 10 and 19 percent of physicians as first and second choices, respectively. Most pharmacies (96 percent) dispensed an enteric-coated preparation of ferrous sulfate for a generic prescription. We believe that many patients are receiving iron tablets with altered release properties (enteric-coated/slow-release). These tablets may fail to provide the desired therapeutic benefit based on the known physiology of iron absorption.

Canada↗
PubMed1978

Effect of ibuprofen on platelet function in normal subjects and hemophiliac patients.

New propionic acid derivatives are claimed to induce a lower incidence of gastrointestinal bleeding and hemostatic disturbance than older anti-inflammatory analgesics such as aspirin. One of these (ibuprofen, Motrin) was given (600 mg orally) to normal subjects and hemophiliac subjects on a random, double-blind basis (lactose placebo). Platelet adhesiveness, aggregation, platelet and red cell counts, percent packed cells, percent hemoglobin, serum ibuprofen levels, and modified Ivy bleeding time were measured before and 2 and 24 hr after drug. Predrug and 24-hr postdrug values were normal, but at 2 hr after drug, adenosine diphosphate, epinephrine, and collagen aggregations were inhibited and bleeding times were slightly but significantly prolonged in the ibuprofen-treated normal subjects. The other parameters tested remained unchanged. Similar results were obtained in the ibuprofen-treated hemophiliac patients, although bleeding time was not prolonged. The results suggest that ibuprofen may be given to hemophiliac subjects with greater safety than some of the older anti-inflammatory drugs.

Adolescent↗
PubMed1978

The female carrier of haemophilia--a problem for the anaesthetist.

Three case histories reflect the difficulties of pre-operative assessment and management of female obligatory carriers for Factor VIII or Factor IX deficiency (haemophilia). The dangers of operation in these individuals is emphasized in view of the often confusing laboratory and clinical findings in this group of patients. A protocol is presented which, if used by the anaesthetist, will provide for logical and safe diagnostic and therapeutic approaches for these patients.

Adult↗
PubMed1975

Coagulation studies in ulcerative colitis and Crohn's disease.

Thromboembolic disease is a known complication of ulcerative colitis, but is rarely reported in Crohn's disease. In this study, we have tried to determine if there are indeed coagulation abnormalities associated with these two diseases. Four groups of patients were studies: (1) patients with ulcerative colitis; (2) patients with Crohn's disease; (3) patients with other diseases; (4) healthy control subjects. In both disease groups, platelet counts, factor V, factor VIII, and fibrinogen levels were found to be elevated, while antithrombin III levels were decreased.

Adolescent↗
PubMed1975

Jamshidi bone marrow needle modification.

A modification of the Jamshidi bone marrow biopsy needle is described. Modification includes designing a removable handle and changes to the obturator. These modifications allow for more precise use, prevention of instrument breakage, and greater convenience for the operator.

Biopsy, Needle↗
PubMedDate not supplied

Filtration of cryoprecipitate: a microscopic assessment of filter depostion.

A recent survey indicated that many Canadian hemophiliacs and physicians did not consider it necessary to filter cryoprecipitate prior to infusion. Experiments were performed to demonstrate that no loss of factor activity resulted from filtration of cryoprecipitate through standard blood filters. Furthermore, examination of the material retained on standard and ultrafiltration elements using scanning and transmission electron microscopy demonstrated the presence of amorphous and fibrillar proteins that proved to be largely composed of fibrin. This was accompanied by cellular material including intact and disintegrating leukocytes, erythrocytes, and platelets. Nonbiologic material was also discovered, including cellulose and plastic debris. This study emphasizes the need for effective filtration of cryoprecipitate.

Chemical Precipitation↗