Endothelial-cell-stimulating angiogenesis factor (ESAF) activates progelatinase A (72 kDa type IV collagenase), prostromelysin 1 and procollagenase and reactivates their complexes with tissue inhibitors of metalloproteinases: a role for ESAF in non-inflammatory angiogenesis

Endothelial-cell-stimulating angiogenesis factor (ESAF) has been shown to activate procollagenase and reactivate complexes of collagenase and gelatinase A with tissue inhibitor of metallo-proteinase (TIMP)-1. In the present paper we show a purification protocol for bovine pineal ESAF and that purified ESAF activates progelatinase A and prostromelysin-1. Unlike the activation of procollagenase by plasmin/plasminogen activator, which requires the presence of stromelysin for full activation, ESAF is able to activate fully all three proenzymes. Purified ESAF is also shown to reactivate the complexes of gelatinase A, collagenase and stromelysin-1 with TIMP-2. Once separated, both enzyme and inhibitor are active; however, ESAF binds to the enzyme in a manner preventing it from further inhibition by TIMP. ESAF is the only physiological molecule able to reactivate the TIMP/enzyme complex.

Noise levels in a cardiac surgical intensive care unit: a preliminary study conducted in secret

Noise in hospitals frequently exceeds recommended levels and has detrimental psychological and physiological effects on patients and staff. The aim of this study was to record the noise levels within the cardiac surgical intensive care unit (CSICU) environment in secret. The device used was a CEL Instruments environmental noise meter concealed in a dummy box featuring temperature and humidity digital displays. It allowed greater than 16 hours recording time at a 1-minute resolution. The 24-hour period was covered by overlapping recordings. The data collected were downloaded onto a personal computer for analysis. The maximum sound level recorded was 100.9 decibel level (dBA), 1 min Lmax (the maximum sound level occurring in a 1-min period). The minimum sound level was 61.3 dBA 1 min Lmax. The continuous background noise was at its lowest at 57.5 dBA 1 min equivalent continuous sound pressure levels (Leq) and at its peak 77.3 dBA 1 min Leq. Noise in the CSICU was above the recommended levels for patients and staff well-being. Future studies will be designed to establish a correlation between sound levels and events.

Adherence to national guidelines for drug treatment of suspected acute myocardial infarction: evidence for undertreatment in women and the elderly

BACKGROUND

Evidence-based guidelines for the treatment of patients with acute myocardial infarction (AMI) have been published and disseminated by the American College of Cardiology and the American Heart Association. Few studies have examined the rates of adherence to these guidelines in eligible populations and the influence of age and gender on highly effective AMI treatments in community hospital settings.

METHODS

Medical records of 2409 individuals admitted to 37 Minnesota hospitals between October 1992 and July 1993 for AMI, suspected AMI, or rule-out AMI, and meeting electrocardiographic, laboratory, and clinical criteria suggestive of AMI were reviewed to determine the proportion of eligible patients who received thrombolytic, beta-blocker, aspirin, and lidocaine hydrochloride therapy. The effects of patient age, gender, and hospital teaching status on the use of these treatments were estimated using logistic regression models.

RESULTS

Eligibility for treatment ranged from 68% (n=1627) for aspirin therapy, 38% (n=906) for lidocaine therapy, and 30% (n=734) for thrombolytic therapy to 19% (n=447) for beta-blocker therapy. Seventy-two percent of patients eligible to receive a thrombolytic agent received this therapy; 53% received beta-blockers; 81% received aspirin; and 88% received lidocaine. Among patients ineligible for lidocaine therapy (n=1503), 20% received this agent. Use of study drugs was lower among eligible elderly patients, especially those older than 74 years (thrombolytic agent: odds ratio, 0.2; 95% confidence interval, 0.1 to 0.4; aspirin: odds ratio, 0.4, 95% confidence interval, 0.3 to 0.6; beta-blocker: odds ratio, 0.4; 95% confidence interval, 0.2 to 0.8). Female gender was associated with lower levels of aspirin use among eligible patients (odds ratio, 0.7; 95% confidence interval, 0.6 to 0.9); and there was a trend toward lower levels of beta-blocker and thrombolytic use among eligible women.

CONCLUSIONS

Use of lifesaving therapies for eligible patients with AMI is higher than previously reported, particularly for aspirin and thrombolytic use in nonelderly patients. Lidocaine is still used inappropriately in a substantial proportion of patients with AMI. Increased adherence to AMI treatment guidelines is required for elderly patients and women.

Prevalence of human immunodeficiency virus and associated risk behaviour in injection drug users in Toronto

During 1989-90, interviews were conducted with 582 current injection drug users in the City of Toronto, 535 of whom also provided blood and/or saliva for anonymous unlinked HIV antibody testing. The rate of seropositivity identified was 4.3% (95% CI 3-6). The subjects were predominantly male, with a mean age of 28.3. The commonest drug of choice was cocaine (70%). Forty-six percent of the subjects reported using someone else's needle in the preceding six months, 60% of these indicating that they always cleaned it first. Eighty-one percent of those interviewed had been in jail at some time since they began injecting; 25% of these had injected while in custody, and of these 61% had shared injection equipment. Eighty-two percent of the men and 85.4% of the women reported opposite sex partners in the previous six months. Only about 20% of men reported consistent condom use, while 22% of females reported condom use at least 75% of the time.

The outcomes of elective laparoscopic and open cholecystectomies

BACKGROUND

The demand for evidence of effectiveness for medical care has prompted the development of epidemiologic approaches to relating the outcomes of care to treatment. This study compares the outcomes of care for patients undergoing the newly introduced laparoscopic cholecystectomy with the results from conventional open cholecystectomies.

METHODS

Consecutive cases of elective cholecystectomy from 35 hospitals (all of the metropolitan and selected rural hospitals in Minnesota) were enrolled in the study. Patients were interviewed on admission to establish baseline symptoms and functional status and to confirm risk factors. Their medical records were abstracted to yield information on risk factors, treatment, and hospital complications. To establish outcomes, patients were sent a questionnaire about their symptoms and functional status six months postoperatively.

RESULTS

Of 3,448 patients studied, 2,490 (72 percent) had a laparoscopic procedure, including 195 cases that were converted to open cholecystectomies. Functional status data were obtained on 2,481 cases (76 percent). Laparoscopic operation was associated with more operative complications (odds ratio 3.02, p < 0.001), but with fewer general complications (odds ratio 0.32, p < 0.001). The mean time to return to work was 15 days for laparoscopic cases compared to 31 days for open procedures (p < 0.001). The only functional outcome difference between the two procedures was that patients who underwent laparoscopic cholecystectomies were more likely than those with conventional cholecystectomies to be able to perform their usual activities at follow-up evaluation (p < .001). There was evidence of a learning curve; the more laparoscopic procedures a surgeon performed, the fewer the operative (p < 0.01) and general (p < 0.0001) complications. There was no indication that the availability of laparoscopic operation was associated with more operations being performed.

CONCLUSIONS

Laparoscopic operation seems to represent a significant advance in getting patients back to a normal life sooner. More attention needs to be given to which patients are most likely to benefit from cholecystectomy of either type. Epidemiologic approaches can be useful in assessing the effectiveness of care. Partnerships between providers and researchers can produce useful effectiveness data by supplementing available clinical records with more detailed outcome data.

Raised endothelial cell stimulating angiogenesis factor in ankylosing spondylitis

Endothelial cell stimulating angiogenesis factor (ESAF) is important in the neovascularisation that precedes new bone formation, and raised levels are found in association with healing fractures and osteoarthritis. We investigated its relevance to the new bone growth that is found at inflammatory sites in ankylosing spondylitis (AS). Forty-one patients with AS were studied clinically and radiographically and had their serum ESAF levels measured. In comparison to age-matched controls the AS patients had significantly raised ESAF levels (p < 0.0001). Within the AS group, patients with relatively higher ESAF levels had no characteristic clinical or radiological features.

Collagenase and gelatinase production by calcifying growth plate chondrocytes

The regulation of cartilage resorption is important both in cartilage pathophysiology and angiogenesis. Previous work has identified a link between calcification and activation of collagenolysis. The aim here was to test whether production of collagenase itself is also calcification-dependent, using a high-density growth plate chondrocyte culture model of calcification. Ultrastructural studies indicated that calcification occurred around large hypertrophic cells. There was no indication of phagocytosis of crystals even by cells lying next to mineral aggregates, although remodeling of the organic matrix by cell processes was evident. Release of collagenase activity increased dramatically between 24 and 48 h postcalcification, from low or undetectable basal levels. In contrast, gelatinase production was not calcification-dependent. Collagenase was released almost entirely in the latent form, being a consequence of increased protein synthesis rather than activation of existing enzyme. This linkage of calcification with latent collagenase production represents part of a coordinated remodeling of both collagenous and mineral components of the matrix which may also extend, in vivo, to the control of microvascular invasion and resorption.

Prevalence of bloodborne infective agents among people admitted to a Canadian hospital

OBJECTIVE

To determine the prevalence rates of hepatitis B surface antigen (HBsAg) and antibodies to the human immunodeficiency virus (anti-HIV) and the hepatitis C virus (anti-HCV) among people admitted to an urban Canadian hospital.

DESIGN

Anonymous unlinked serosurvey.

SETTING

A 420-bed teaching hospital in Toronto.

PARTICIPANTS

All 3000 patients admitted to the hospital on weekdays from January to June 1990. An attempt was made to exclude those who were readmitted during the study period.

INTERVENTIONS

Serum samples from all the patients were tested for HBsAg and anti-HIV, and 1306 samples were also tested for anti-HCV by means of enzyme immunosorbent assays; reactions were confirmed by means of specific antibody neutralization or immunoblot assay.

MAIN RESULTS

The prevalence rates of HBsAg, anti-HIV and anti-HCV were 2.1% (95% confidence interval [CI] 1.6% to 2.6%), 0.6% (95% CI 0.3% to 0.9%) and 0.5% (95% CI 0.1% to 0.9%) respectively.

CONCLUSIONS

This is the first report defining rates of infection with these bloodborne agents among patients admitted to a Canadian hospital. The observed rates likely reflect the patient population served by our hospital and do not necessarily apply to other Canadian centres. The results support the use of universal precautions in health care settings.

Concentrations of endothelial-cell-stimulating angiogenesis factor, a major component of human uterine angiogenesis factor, in human and bovine embryonic tissues and decidua

Embryonic development involves the establishment of new patterns of vascular growth in the fetus and within the lining of the womb. A factor, human uterine angiogenesis factor, has been purified from the decidua and stimulates the growth of blood vessels in collagen sponge implants and in the chick chorioallantoic membrane. Evidence is presented that suggests that a major active component of human uterine angiogenesis factor is an activator of latent matrix metalloproteinases, of low M(r), called endothelial-cell-stimulating angiogenesis factor and that this factor is present in substantial quantities in a number of embryonic tissues.

The Ontario HIV seroprevalence study of childbearing women: results from the first year of testing

The Ontario HIV Seroprevalence Study of Childbearing Women is an unliked anonymous seroprevalence study designed according to the well-established ethical and legal guidelines for such studies. Commencing in November, 1989, randomly selected neonatal heelprick specimens were tested for the presence of HIV antibodies after all identifying information had been permanently and irrevocably unlinked from the specimens. During the first year of the study 94,119 (approximately 60% of all submitted specimens) were tested. Twenty-six specimens which were repeatedly reactive by EIA were confirmed as positive for an overall crude seroprevalence rate of 2.8 per 10,000 women having live births (95% CI: 1.8-4.1). Twenty-five of the 26 confirmed seropositive results came from babies born in hospitals in the Metropolitan Toronto, Ottawa-Carlton, or Hamilton-Peel-Halton regions.

Doxazosin in the management of hypertensive diabetes--a cautionary note (?)

Twenty-two patients with diabetes and hypertension were treated with Doxazosin. An acceptable fall in blood pressure was found with 1 mg. in 50% of patients and 2-8 mgs. in 50%. An increase in HDL cholesterol and a fall in LDL cholesterol levels which reached statistical significance was observed. A small but significant increase in HBA1 levels occurred in the 50% of patients on the higher Doxazosin dose.

Detection of Norwalk-like virus and specific antibody by immune-electron microscopy with colloidal gold immune complexes

Direct electron-microscopy (DEM), immune electron microscopy (IEM) and four different procedures of immune electron microscopy with colloidal gold immune complexes were evaluated for the detection of Norwalk-like virus and specific antibody. A solid-phase immune electron microscopy with colloidal gold immune complexes-triple layer method (SPIEMGIC-TLM) is developed for screening patients' specimens for the detection of Norwalk-like virus and its specific antibody. The method demonstrates low non-specific background labelling and is simple, sensitive and easy to perform. A quadruple layer method (SPIEMGIC-QLM), which is a modification of the triple layer method, has been established by adding a cross-linking anti-IgG layer to amplify the reaction and to provide a more sensitive test which is suitable for screening monoclonal antibodies prepared against 32-34-nm Norwalk-like virus isolated in our laboratory.

Increased endothelial cell stimulating angiogenesis factor in patients with tibial fractures

Angiogenesis is an important step in the normal process of fracture healing, irrespective of the method of fixation. Using a quantitative assay, the amount of endothelial cell stimulating factor (ESAF) has been determined in a small group of patients with tibial fractures. ESAF levels were found to be increased when compared with normal volunteers, although this increase was relatively less in fractures held with intramedullary nails than with external fixation.

Activation of the matrix metalloproteinase inhibitor complex by a low molecular weight angiogenic factor

Tissue inhibitor of matrix metalloproteinases is the major inhibitor of the collagenolytic enzymes and the inhibitory complex has been thought to be irreversible. In this paper we show that a low molecular weight non-protein endothelial cell stimulating angiogenic factor is able to reactivate the enzyme from the inhibitor complex and liberate free inhibitor. The importance of an angiogenic factor able to initiate limited degradation of extra-cellular matrix such that space is created for new capillary growth is discussed.

Production of endothelial cell stimulating angiogenesis factor (ESAF) by chondrocytes during in vitro cartilage calcification

The aim of this study was to identify the stimulus for production of the latent collagenase and angiogenic activator ESAF by growth plate chondrocytes. Stimulation correlated most closely with matrix calcification. Alkaline phosphatase was necessary for calcification (and so stimulation of ESAF production) but we could find no evidence for a direct link with ESAF production. ESAF production was also stimulated by addition of preformed mineral to non-calcified cultures but was inhibited by dexamethasone. Protein synthesis was necessary for the stimulation of ESAF production by calcification, though ESAF is not itself a protein. Based on these findings we suggest that chondrocytes, at a suitable stage of maturation in the growth plate, are stimulated to produce ESAF by the proximity of crystals in the matrix. Stimulation, which may consist of the induction of an enzyme or transport protein, leads to the release of this potent activator of collagenolysis as part of the angiogenic cascade.

Determinants of upper esophageal sphincter pressure in dogs

Chronic experiments were done on six dogs fitted with EMG electrodes on pharyngeal and esophageal musculature. Electromyographic activity of the cricopharyngeus was recorded in awake and sedated animals with and without manometric recordings as well as during esophageal distension. Intraluminal upper esophageal sphincter (UES) pressure had two distinct components; active contraction accompanied by cricopharyngeal EMG activity and passive elasticity that persisted in the absence of EMG activity. Between swallows, the cricopharyngeal EMG activity patterns observed were of either tonic activity, no activity, or phasic activity with inspiratory bursts. The activity level was markedly affected by anesthesia, phonating, whining, panting, level of alertness, or changes in head posture. A brisk UES contraction was elicited in response to passage of the manometric assembly and to intraesophageal balloon distension. Persistent EMG augmentation after stationing of the manometric sensor suggested that intraluminal manometry tends to exaggerate resting sphincter pressure. We conclude that electrical activity of the cricopharyngeus, and by inference UES pressure, is markedly affected by many variables that are difficult to control during clinical or experimental determinations of UES pressure.

Late onset adrenal hyperplasia in a group of Irish females who presented with hirsutism, irregular menses and/or cystic acne

The aims of this study were to determine the frequency of late-onset adrenal hyperplasia due specifically to 21-hydroxylase deficiency in a group of Irish women who presented at a Dublin Clinic with symptoms of hyperandrogenism, including hirsutism, menstrual irregularities and/or cystic acne, and to determine if those with 21-hydroxylase deficiency showed particular HLA associations. 119 women had blood samples taken basally and 1 h after an injection of 0.25 mg synacthen with the following hormones profiled: 17-hydroxyprogesterone, 11-deoxycortisol, androstenedione, testosterone, DHEAS and cortisol. Blood sampling was carried out between 0900 and 1000 h during the early follicular phase of the menstrual cycle (when applicable). Ninety-six subjects were new referrals to the Clinic for investigation of hyperandrogenism and 23 were acting as controls. In this study, 6% of patients showed evidence of partial 21-hydroxylase deficiency. In addition, 3 of the 6 with partial 21-hydroxylase deficiency had normal baseline levels of 17-hydroxyprogesterone, with the biochemical abnormality becoming manifest only on synacthen stimulation. Late-onset adrenal hyperplasia due to partial deficiency of this enzyme should always be considered as a possible diagnosis in women who present with symptoms of hyperandrogenism. Synacthen stimulation is an important diagnostic tool in elucidating partial enzyme deficiency as baseline 17-hydroxyprogesterone may be normal in such patients.