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Reasons for Performing Study: Standard bacteriological methods for identifying Taylorella equigenitalis in cervical smears are time consuming. Therefore, a more rapid real-time PCR assay was evaluated for its suitability in screening swabs., Objective: To compare the results of a commercially available real-time PCR assay with routine microbiological culture for the identification of T. equigenitalis, the causative organism of contagious equine metritis, in equine genital swab samples, under 'field trial' conditions., Materials and Methods: Routine prebreeding genital swabs (n=2072) collected from Thoroughbred mares and stallions during 2009 were examined together with stored T. equigenitalis positive material. Swabs were cultured for T. equigenitalis using standard microbiological techniques. Bacterial lysates were isolated from the swabs and examined for the presence of a 16S DNA fragment of T. equigenitalis, using a commercial multiplex real-time PCR assay system., Results: There was complete concordance between positive and negative results obtained by the 2 methods. Real-time PCR also detected T. equigenitalis DNA from swabs that were negative using standard microbiological culture after 6 months' storage at +4 degrees C but from which T. equigenitalis had been isolated following collection. The sensitivities of real-time PCR and bacterial culture were both 10(-3) (equivalent to 3 colony-forming units)., Conclusion and Clinical Relevance: Routine bacterial culture of T. equigenitalis requires an incubation period of not less than 7 days before a conclusive negative result can be obtained, whereas bacterial extraction and real-time PCR assay can be completed in less than 6 h. The commercially-available PCR assay tested provided a rapid and reliable method for the identification of T. equigenitalis from equine genital swabs and could be usefully employed for the screening of mares and stallions for preseason Horserace Betting Levy Board (HBLB) Code of Practice and in other situations such as for bloodstock sales screening requirements, overcoming the current delays imposed by bacterial culture requirements. Its use could be quality assured by the existing HBLB biannual testing scheme for designated laboratories.

Series of well-documented case reports strongly suggest a causal association between tiaprofenic acid and a form of aseptic cystitis, which can cause serious and long-term morbidity if the drug is not withdrawn promptly. These findings are supported in the Australian and UK spontaneous reporting data-bases. Using sales data as the denominator, a comparison of NSAIDs in the WHO drug monitoring data-base indicates that the reaction is specific to tiaprofenic acid and cannot be accounted for by changes in reporting patterns in certain countries or years. Delayed recognition is an important feature of this reaction and possible reasons for this are discussed. Comparison of the risk profiles of seven NSAIDs indicated that tiaprofenic acid had the poorest risk profile, compared with NSAIDs of similar efficacy, when cystitis reports were included. The results suggest that combining spontaneous reports, classified according to severity, with sales data may enhance the ability of drug monitoring data-bases to contribute to risk benefit appraisals.

Objective: The present study was performed both to investigate whether there might be a difference between the selective serotonin re-uptake inhibitors, (SSRIs) with regard to the incidence of withdrawal reactions, and to describe the associated symptoms. From the WHO database, therefore, all case reports from the year of introduction for each of the SSRIs, fluoxetine, paroxetine and sertraline, were retrieved. Sales figures were obtained from Intercontinental Medical Statistics International. The reporting rates were calculated as the number of reports per million defined daily doses (DDDs) sold per year., Results: The reporting rate of withdrawal reactions for paroxetine was found to be higher than that for sertraline and fluoxetine in each of the countries selected for detailed analyses (US, UK and Australia), as well as for all 16 countries combined. Moreover, using the WHO system of organ classification, the ratio of central nervous system to psychiatric withdrawal symptoms was 1.9 and 2.1 for paroxetine and sertraline, respectively, whereas that for fluoxetine was 0.48, indicating a possible qualitative difference between the SSRIs with respect to the nature of the withdrawal syndrome.

Objective: To evaluate the incidence of discontinuation of and changes in treatment after newly prescribed courses of antihypertensive drugs of the four primary therapeutic classes: beta blocker, calcium channel blocker, and angiotensin converting enzyme inhibitor., Design: A retrospective analysis of patients on an automated database of 1.2 million patients was conducted on visits between 1 October 1992 and 30 September 1993., Setting: General practices in the United Kingdom., Subjects: 37,643 patients with hypertension receiving a relevant drug in the time period were identified. A new course of treatment in at least one of the four therapeutic classes, defined as a drug not prescribed in the previous four months, was observed in 10,222 patients aged > or = 40 years., Main Outcome Measures: Patients changing to other treatment or discontinuing after initiating a new course of treatment, defined as the absence of a refill prescription for the new drug or another in its category within a six month observation period., Results: Changes in or discontinuation of treatment were frequently observed, and by month six continuation rates ranged between 40% to 50% for all four classes of drugs., Conclusion: Low rates of continuation with a newly prescribed antihypertensive drug exist regardless of which drug is prescribed.

Awareness of the need to continue the safety assessment of new drugs into the post-marketing period has continued to increase over the past few years. The stage has been reached where there is, for all practical purposes, unanimous agreement that all new drugs, particularly those intended for widespread use and/or long-term administration, be subjected to some form of post-marketing monitoring. In many cases nationally sponsored spontaneous reporting systems are claimed to be sufficient to meet the needs without any critical appraisal being made of the suitability or reliability of this method. The adoption of 'pharmacovigilance' (spontaneous reporting) as the system for the whole European Community (EC) emphasizes the faith that has been placed in the system. At a recent symposium (Management Forum, 9-10 March, 1992) on post-marketing safety evaluation, more than half of the 16 papers presented were entirely or predominantly concerned with spontaneous reporting systems, which is a pattern common to other meetings on this topic. The Committee on Safety of Medicines (CSM) has referred to spontaneous reporting as the cornerstone of post-marketing surveillance which has further endorsed a general feeling of confidence that the system will meet our societal needs even though its scientific capability may be deficient. It is the purpose of this paper to challenge these assumptions and to make an objective appraisal of the various methods available.

Spontaneous adverse drug reaction (ADR) reporting is the mainstay of national and international drug safety evaluation in the post-approval phase. A major criticism of the method has been a high, but essentially unquantifiable, level of under-reporting by doctors. A direct comparison has been made between spontaneous ADR reporting and an observational event monitoring system for a group of more than 44,000 patients receiving one or other of a group of seven new drugs. The data suggests that under-reporting by the spontaneous system may be as high as 98% for several clinical events believed to be associated with drug treatment.

An event-monitoring, observational cohort study was conducted in 10,800 patients treated with the nonsteroidal anti-inflammatory agent (NSAID) nabumetone and in 2005 patients treated with a selection of other NSAIDs. A total of 2986 doctors in general practice in the UK participated in the study, which involved the provision of a registration report at the beginning of the study and follow-up reports at 1, 3, 6, and 12 months. The methodology which was developed was successful in collecting demographic, diagnostic, drug use, clinical event and adverse reaction data in everyday medical practice.

Serial determinations, using plasma fibrinogen gel chromatography as well as standard methodology, demonstrated that six children with severe glomerulonephritis, characterized on renal biopsy by glomerular necrosis and crescent formation, had persistent evidence of intravascular coagulation. Based on these observations, therapy with anticoagulants and azathicoagulants and azathioprine was instituted for one year; treatment with anticoagulants was continued for a second year. Anticoagulant therapy was initiated with heparin, followed by oral anticoagulation with phenindione and dipyridamole. In contrast to our earlier experience with similar patients, each of the present patients improved. Urinalyses returned to normal and glomerular filtration rates to near normal values in all patients at the end of the treatment period and have remained so for up to 3.9 years since treatment has been completed. Post-treatment biopsies showed remarkable improvement, with virtually no glomerulosclerosis even in patients who had had a high incidence of glomerular crescents before treatment. It is suggested that the therapeutic regimen favorably influenced the natural history of disease and that plasma fibrinogen chromatographic findings may be helpful in selecting patients likely to benefit from the use of anticoagulant therapy.

Four patients undergoing urokinase infusion therapy for acute occlusive cerebrovascular disease had intracerebral hemorrhage in the ischemic hemisphere. Three patients died during the acute phase of their illness and an autopsy was performed on two. The pathogenesis of cerebral bleeding in these case reports is discussed.

Plasma fibrinogen chromatography is a method for quantification of high molecular weight fibrinogen complexes (HMWFC), native fibrinogen and other fibrinogen derivatives in plasma. Enchanced formation of fibrin, intravascular coagulation, thrombus formation, etc., are reflected by elevation of plasma HMWFC, and the method distinguishes between subjects with normal and pathological rates of fibrin formation. Serial standard blood coagulation assays, including plasma fibrinogen chromatography, and neurological studies were performed on 220 patients admitted to a stroke unit. Findings from patients with cerebral infarction were compared against those of three control groups: (1)normals, (2)a stroke control group and(3)a stroke risk factor group. Plasma HMWFC findings were significantly (p less than 0.001) higher in the stroke risk factor group than in the normals. Plasma HMWFC values were significantly higher (p less than 0.001) in the cerebral infarction patients than in any of the control groups, and plasma fibrinogen, plasminogen, alpha1-antitrypsin and alpha2-macroglobulin also were significiantly higher (p less than 0.001) in the patients. The greater the degree of initial neurological deficit, the greater were plasma HMWFC values (p less than 0.001), and high HMWFC values were associated with poor clinical outcome. Plasma HMWFC values were significantly higher (p less than 0.001) in patients with intracerebral hemorrhage, subarachnoid hemorrhage and cerebral embolism. These findings docunment the fact that a high proportion of stroke patients have coagulopathy, characterized by pathological enhancement of fibrin formation.

We conducted a dose-response study in 23 postmenopausal women to compare the physiologic effects of transdermal estradiol and oral conjugated equine estrogens. The doses studied were 25, 50, 100, and 200 micrograms of transdermal estradiol per 24 hours, and 0.625 and 1.25 mg of oral conjugated estrogens. Transdermal estradiol increased circulating concentrations of estradiol and estrone. Oral conjugated estrogens also raised the levels of estrogen, particularly estrone. Both preparations lowered gonadotropin levels, decreased the percentages of vaginal parabasal cells, increased the percentage of superficial cells, and lowered urinary calcium excretion. The effects of 0.625 and 1.25 mg of oral estrogens were similar to those of 50 and 100 micrograms of transdermal estradiol per 24 hours, respectively. Oral estrogens significantly increased circulating levels of renin substrate, sex-hormone-binding globulin, thyroxine-binding globulin, and cortisol-binding globulin; transdermal estradiol had no effect. The higher dose of oral estrogens had favorable effects on concentrations of low-density and high-density lipoproteins, but transdermal estradiol did not. Neither preparation affected any of the four clotting factors studied. These data indicate that transdermal estradiol can elicit many of the desirable actions of estrogen while avoiding the pharmacologic effects of oral estrogens on hepatic proteins.

Thirty-one patients with acute cerebral infarction were treated with the thrombolytic agent urokinase for either a single or a double infusion period, each of ten hours. The effects of urokinase therapy administered at dosage rates of 1,200, 1,500 or 1,700 CTA urokinase units per pound of body weight per hour were followed by serial blood coagulation and other biochemical studies. In the dosage used, urokinase produced a prompt sustained increase, 20-fold to 40-fold, of plasma thrombolytic activity with relatively minor disturbance of the blood coagulation system. Nevertheless, hemorrhagic complications occurred in several patients and distinctly favorable therapeutic effects were not observed.

Blood coagulation function was serially studied in 84 children with nephrotic syndrome. Fifty-eight had minimal change disease, six had focal glomerulosclerosis and 20 had other forms of renal disease associated with the nephrotic syndrome. Qualitatively similar abnormalities in fibrinogen metabolism were present in all groups with clinically overt nephrotic syndrome; plasma fibrinogen concentration and high molecular weight fibrin(ogen) complexes (HMWFC) were grossly elevated (P less than 0.001 in most groups). With disease remission fibrinogen and HMWFC concentrations decreased to the normal range, usually with concomitant transient increase in plasma fibrinolytic activity (P less than 0.02). Alterations in concentrations of other proteins involved in coagulation and fibrinolysis differed depending on the underlying cause for the nephrotic syndrome. Antithrombin III concentration was normal except in the focal glomerulosclerosis group. The results demonstrate that a coagulopathy characterized by pathological degree of thrombin action on fibrinogen complicates the nephrotic state and may be initiated by different mechanisms. It is suggested that this coagulopathy, which remits with clinical improvement, is consequent upon local intrarenal activation of the blood coagulation system.

Two hundred twenty patients admitted to a Coronary Care Unit were studied by serial plasma fibrinogen chromatography--a method for quantification of HMWFCs, native fibrinogen, and other fibrinogen derivatives in plasma. Enhanced formation of fibrin (intravascular coagulation/thrombosis) is reflected by elevation of plasma HMWFC. One hundred ten patients suffering from documented acute myocardial infarction showed early, sharp elevation of plasma HMWFC (p less than 0.001 when compared to normal and cardiac control groups), a finding which persisted for 10 to 20 days after infarction. Forty-three of the patients did not receive anticoagulant therapy, and the others received either initial heparin, heparin plus warfarin, or werfarin therapy. Plasma fibrinogen chromatographic findings, days 1 to 5, did not differ between the anticoagulated and nonanticoagulated treatment groups, although there were minor differences in the data for days 6 to 10. The results demonstrate that patients with acute myocardial infarction develop a coagulopathy characterized by enhanced fibrin formation, which is influenced to only a minor degree by conventional dosage anticoagulant therapy.

Plasma fibrinogen chromatography and other relevant determinations of factors of known importance in thrombus production and dissolution were done serially in 19 hospitalized burned patients. The findings indicate that the coagulation mechanism was chronically activated and that, judging from the observed, sustained elevation of circulating high molecular weight fibrin (ogen) complexes, intravascular clotting was occurring at a pathological, if variable, rate. In patients older than 50 years of age, a relatively impaired thrombolytic response was also found; the latter finding is of special interest, as it provides biochemical substantiation for the well-recognized clinical proclivity of elderly burn patients to thromboembolic complications.

A new procedure, plasma fibrinogen chromatography, has been utilized, together with other blood coagulation assays, to quantify fibrin formation in 43 children with acute poststreptococcal glomerulonephritis (AGN) from the time of hospitalization until recovery. During the prediuretic phase of AGN, significant evidence for substantial increase in fibrin formation (intravascular coagulation) included gross increase in plasma high molecular weight fibrinogen complexes (HMWFC), the development of either hypo- or hyperfibrinogenemia and gross depression of coagulation factor XIII concentration and of alpha2-macroglobulin concentration. During the diuretic phase of the disease, these abnormalities regressed and evidence of enhanced plasma fibrinolytic activity, documented by an increase in fibrinogen first derivative, was detected. Concomitantly, urinary excretion of fibrin(ogen) degradation products (FDP) underwent substantial increase. With disease recovery, which occurred in all children, urinary FDP excretion ceased and all coagulation findings normalized.

Coagulation factor XIII and plasma fibrinogen chromatographic assays have been performed serially in patients suffering from acute myocardial and cerebral infarction, and in others with disseminated intravascular coagulation. The findings were compared with 2 groups of "controls"; normal clinically-well subjects and hospitalized patients with cerebral infarction who exhibited minimal, stable, or improving neurological deficits. Substantial depression of factor XIII concentrations developed in the 3 patient groups, together with concomitant significant increases in the proportion and concentration of plasma high molecular weight fibrin(ogen) complexes (HMWFC). An inverse correlation (p less than 0.05) between coagulation factor XIII concentration and percentage of HMWFC was demonstrated in the early stages of the illness. These findings suggest that depression of coagulation factor XIII concentration in these states, is secondary to extravascular or intravascular coagulation and may reflect its degree.

The kinetic parameters for release of fibrinopeptide A (FPA) from human fibrinogen by thrombin are: Km = 2.3 X 10(-6)M and Vmax. = 1.1 X 10(-10)mol of FPA/s per unit of thrombin; for fibrin formation, Km is similar to that for FPA release, but, the conditions of the present study, Vmax. was approximately half of that for FPA release. The formation of fibrin polymer before the sol-gel transition was studied by gel-permeation chromatography combined with effluent analysis for fibrinogen antigen and residual FPA. Polymer formation in purified fibrinogen incubated with thrombin proceeded as a bimolecular association of exposed sites in a manner predicted by probability calculations and assuming random FPA cleavage. Each oligomer consisted of n molecules of fibrin monomer and two fibrinogen molecules, each of the latter lacking one FPA molecule, i.e. each oligomer, regardless of molecular size, retains two FPA molecules. The addition of 5 mM-CaCl2 to the reaction mixture changed the rate of polymer formation, so that dimer was no longer the prevalent oligomer; in the presence of Ca2+, the trimer was the oligomer in highest concentration. The polymers formed in the presence of calcium were similar in composition to those without, i.e. 2 mol of FPA/mol of oligomer. EDTA-treated plasma samples incubated for short periods of time, 30s or less, with thrombin ranging in concentration up to 1 N.I.H. unit/ml did not form clots during the 10-15 min period of observation until they were applied to the column, though a large proportion of the available FPA was cleaved (maximum 45%). The soluble polymers in plasma were mostly of the high-Mr variety (tetramer and greater); these high-Mr polymers contained less than 2 mol of FPA/mol of polymer, whereas dimer and trimer in plasma were similar to those in the purified systems, i.e. 2 mol of FPA/mol.

The responses of the blood coagulation and related systems were studied in 23 postmenopausal women, all of whom received, in randomized order, therapy with conjugated oral estrogens (0.625 and 1.25 mg daily) and transdermally administered estradiol in doses of 25, 50, 100, and 200 micrograms/24 hr. Neither plasma fibrinopeptide A determinations nor plasma fibrinogen chromatographic findings were altered; thus there is no evidence of accelerated fibrinogen turnover with either form of therapy. However, alpha 1-antitrypsin and plasminogen concentrations were significantly increased with the higher dosage of oral but not with transdermally administered estrogen. Similarly, ceruloplasmin concentration was significantly elevated with both oral doses but was unchanged by transdermal therapy.