Effect of glycoprotein IIb/IIIa inhibitors on the individual components of composite endpoints used in clinical trials of unstable angina and non-Q-wave myocardial infarction

Inhibitors of the platelet glycoprotein (GP) IIb/IIIa receptor complex have recently been approved for the treatment of patients with unstable angina and non-Q-wave myocardial infarction (MI). We performed a meta-analysis to ascertain the effect of these agents on the individual endpoints of death, myocardial infarction, refractory ischemia, and major bleeding after 30 days of follow-up. Five randomized, placebo-controlled trials involving 17,255 patients were identified. The odds ratios for each of the endpoints in each trial were calculated and combined using a fixed-effects model. There was no significant reduction in death (OR, 0.87; 95% CI, 0.73-1.03; P = 0.1), myocardial infarction (OR, 0.91; 95% CI, 0.82-1.004; P = 0.06), or refractory ischemia (OR, 0.92; 95% CI, 0.78-1.1; P = 0.36) in patients treated with GP IIb/IIIa inhibitors. There was a significant increase in major bleeding following treatment with GP IIb/IIIa inhibitors (OR, 1.2; 95% CI, 1.06-1.4; P = 0.005). When used to treat unstable angina and non-Q-wave MI, this new class of agents appears to be associated with minimal clinical benefit and an increase in major bleeding complications.

Staging of advanced ovarian cancer: comparison of imaging modalities--report from the Radiological Diagnostic Oncology Group

PURPOSE

To compare ultrasonography (US), magnetic resonance (MR) imaging, and computed tomography (CT) for diagnosing and staging advanced ovarian cancer.

MATERIALS AND METHODS

US, CT, and MR imaging were performed in 280 patients. Images were read by three radiologists from each of the five hospitals. Image analysis included determination of malignancy within the peritoneum (11 sites), lymph nodes (10 sites), and hepatic parenchyma. The standard of reference was based on surgical and histopathologic findings. Statistical methods used were receiver operating characteristic (ROC) curve analysis, pairwise comparison of areas under the ROC curves (A(z)), analysis of sensitivity and specificity pairs, and assessment of agreement between the degree of suspicion and standard of reference.

RESULTS

There were 118 patients with malignant tumors; 73 (62%) had stage III or IV disease. Metastases were found in the peritoneum in 70 (59%), nodes in 20 (17%), and liver in seven (6%) cases. In the peritoneum, MR imaging and CT (A(z) = 0.96 for both) were more accurate than US (A(z) = 0.86), especially in the subdiaphragmatic spaces and hepatic surfaces. MR imaging and CT were more sensitive than US (95%, 92%, and 69%, respectively) for peritoneal metastases. MR imaging was more accurate than CT for detection of lymph node metastases (A(z) = 0.76 vs 0.57, P =.04). In the liver, the A(z) values for the three modalities were 0.77-0.94.

CONCLUSION

CT and MR imaging are equally accurate, and either modality can be used to stage advanced ovarian cancer.

Effect of early revascularization on mortality from cardiogenic shock complicating acute myocardial infarction in California

Recent retrospective analyses of treatment of cardiogenic shock suggest that early revascularization reduces mortality. All nonfederal hospital admissions in California for 1994 with a diagnosis of acute myocardial infarction (AMI) were identified. From that cohort, patients who developed cardiogenic shock were selected to determine demographic features, procedure utilization, and outcomes of their admission compared with patients with AMI without cardiogenic shock. Multivariate logistic regression analysis was performed to assess the effect of early revascularization on survival of patients in cardiogenic shock. Cardiogenic shock was identified in 1,122 patients. Mean age was 70.4 years, 45% of patients were women, and 28% had diabetes mellitus. Shock patients were more likely to be older, diabetic, women, and having an anterior Q-wave AMI. Overall in-hospital mortality for patients with shock was 56%. Patients referred for early revascularization had more favorable risk profiles, but after multivariate analysis early revascularization remained a powerful, independent predictor of improved survival, reducing the odds of death by 80%. This population-based study suggests that early revascularization may improve in-hospital survival of patients with cardiogenic shock complicating AMI, even after adjustment for baseline differences between patients who underwent early revascularization and those who did not.

Post-roll effects on attitude perception: "the Gillingham Illusion"

BACKGROUND

Several aircraft each year are lost because of an unexplained collision with the ground. The attitude of most of these aircraft prior to impact was nose-low and with excessive bank, i.e., greater than 90 degrees . Prior to these accidents, each aircraft was noted as either changing heading or making an abrupt roll.

HYPOTHESIS

Could there be some underlying tendency for the pilot to make unnoticed stick inputs after completing a roll from one bank angle to another?

METHODS

Since ground-based flight simulators cannot create the true sensation of rolling an aircraft from one side to the other, the instrumented CALSPAN NT-33 aircraft was used for this study. Six pilots were given a series of three roll rates and two head positions while the aircraft automatically changed bank from 45 degrees of bank in one direction to 45 degrees of bank in the opposite direction. The subject's view of the external visual scene was restricted with a blue-amber vision restricting transparency combination. All attitude-indicating instruments were blanked, requiring the subjects to make stick inputs based on their vestibular (somatosensory) feedback.

RESULTS

Subjects experienced a consistent tendency to increase bank angle after given control of the aircraft immediately following the roll maneuver, while thinking they were maintaining a constant bank angle. In some cases, the pilots rolled the aircraft completely inverted.

CONCLUSION

When pilots rely on their perception of bank, following a roll, they will inadvertently increase their bank in the direction of the previous roll.

A naturally occurring mutation near the amino terminus of alphaIIb defines a new region involved in ligand binding to alphaIIbbeta3

Decreased expression of functional alphaIIbbeta3 complexes on the platelet surface produces Glanzmann thrombasthenia. We have identified mutations of alphaIIb(P145) in 3 ethnically distinct families affected by Glanzmann thrombasthenia. Affected Mennonite and Dutch patients were homozygous and doubly heterozygous, respectively, for a P(145)A substitution, whereas a Chinese patient was doubly heterozygous for a P(145)L substitution. The mutations affect expression levels of surface alphaIIbbeta3 receptors on their platelets, which was confirmed by co-transfection of alphaIIb(P145A) and beta3 cDNA constructs in COS-1 cells. Each mutation also impaired the ability of alphaIIbbeta3 on affected platelets to interact with ligands. Moreover, when alphaIIb(P145A) and beta3 were stably coexpressed in Chinese hamster ovary cells, alphaIIbbeta3 was readily detected on the cell surface, but the cells were unable to adhere to immobilized fibrinogen or to bind soluble fluorescein isothiocyanate-fibrinogen after alphaIIbbeta3 activation by the activating monoclonal antibody PT25-2. Nonetheless, incubating affected platelets with the peptide LSARLAF, which binds to alphaIIb, induced PF4 secretion, indicating that the mutant alphaIIbbeta3 retained the ability to mediate outside-in signaling. These studies indicate that mutations involving alphaIIb(P145 )impair surface expression of alphaIIbbeta3 and that the alphaIIb(P145A) mutation abrogates ligand binding to the activated integrin. A comparative analysis of other alphaIIb mutations with a similar phenotype suggests that these mutations may cluster into a single region on the surface of the alphaIIb and may define a domain influencing ligand binding. (Blood. 2000;95:180188)

Bioterrorism preparedness and local public health agencies: building response capacity

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Local perivascular delivery of basic fibroblast growth factor in patients undergoing coronary bypass surgery: results of a phase I randomized, double-blind, placebo-controlled trial

BACKGROUND

Angiogenesis is a promising treatment strategy for patients who are not candidates for standard revascularization, because it promotes the growth of new blood vessels in ischemic myocardium.

METHODS AND RESULTS

We conducted a randomized, double-blind, placebo-controlled study of basic fibroblast growth factor (bFGF; 10 or 100 microg versus placebo) delivered via sustained-release heparin-alginate microcapsules implanted in ischemic and viable but ungraftable myocardial territories in patients undergoing CABG. Twenty-four patients were randomized to 10 microg of bFGF (n=8), 100 microg of bFGF (n=8), or placebo (n=8), in addition to undergoing CABG. There were 2 operative deaths and 3 Q-wave myocardial infarctions. There were no treatment-related adverse events, and there was no rise in serum bFGF levels. Clinical follow-up was available for all patients (16.0+/-6.8 months). Three control patients had recurrent angina, 2 of whom required repeat revascularization. One patient in the 10-microg bFGF group had angina, whereas all patients in the 100-microg bFGF group remained angina-free. Stress nuclear perfusion imaging at baseline and 3 months after CABG showed a trend toward worsening of the defect size in the placebo group (20.7+/-3.7% to 23.8+/-5.7%, P=0.06), no significant change in the 10-microg bFGF group, and significant improvement in the 100-microg bFGF group (19.2+/-5.0% to 9.1+/-5.9%, P=0.01). Magnetic resonance assessment of the target ischemic zone in a subset of patients showed a trend toward a reduction in the target ischemic area in the 100-microg bFGF group (10.7+/-3.9% to 3. 7+/-6.3%, P=0.06).

CONCLUSIONS

This study of bFGF in patients undergoing CABG demonstrates the safety and feasibility of this mode of therapy in patients with viable myocardium that cannot be adequately revascularized.

Circumferential abdominal skin defect possibly due to umbilical cord encirclement

We report on a newborn black male twin with a distinctive circumferential abdominal skin defect who was identified through the Active Malformation Surveillance Program at the Brigham and Women's Hospital. There were no other malformations, and amniotic disruption was not present. Although it cannot be proven, we believe that this skin defect may have been caused by in utero encirclement of the abdomen by an umbilical cord.

Two pathways for the induction of apoptosis in human lymphocytes

PURPOSE

To assess the roles of cell membranes and DNA as targets in radiation-induced apoptosis.

MATERIALS AND METHODS

Peripheral blood lymphocytes from normal human donors were exposed to different types of apoptosis-inducing agents. Several measures of apoptosis were used to compare the kinetics of the processes induced, as well as to correlate the processes with DNA damage and membrane oxidation.

RESULTS

Two kinetically distinct processes were observed. DNA-damaging agents, such as ionizing radiation, bleomycin, cisplatin and the topoisomerase inhibitor m-amsacrine, induced apoptosis by a kinetically slow process initiated by DNA damage and dependent on protein synthesis, but which did not correlate with membrane oxidation. Conversely, the agents t-butyl hydroperoxide and cumene hydroperoxide induced apoptosis by a kinetically fast process independent of protein synthesis and which did correlate with membrane oxidation.

CONCLUSIONS

Slowly repaired or unrepairable DNA lesions, such as some of those produced by ionizing radiation exposure, trigger apoptosis by a kinetically slow process. This slow apoptotic pathway is distinct from a fast process not induced by radiation but which is induced by membrane-oxidizing agents.

Apoptosis and the adaptive response in human lymphocytes

PURPOSE

To determine whether the sensitivity of human lymphocytes for apoptosis induced by either a membrane oxidizing agent or a DNA damaging agent is modified by an adaptive response.

MATERIALS AND METHODS

Peripheral blood lymphocytes from normal human donors were exposed to low doses of the DNA damaging agent gamma-radiation, or the membrane oxidizing agent t-butyl hydroperoxide (t-BuOOH), incubated for various times and then tested for their sensitivity to induction of apoptosis by a subsequent exposure to a high dose of either agent. Apoptosis was measured using a fluorescent assay of DNA unwinding or a terminal deoxynucleotide transferase assay.

RESULTS

The results show that Go lymphocytes pre-exposed to an adapting dose of radiation or DNA strand breaking agent are not protected but can become sensitized to subsequent apoptosis induced by radiation (a kinetically slow process). Inter- and intraindividual variations were observed. However, neither pre-exposure to radiation nor to a membrane oxidizing agent sensitized lymphocytes from any donor to apoptosis induced by a membrane oxidizing agent (a kinetically fast process).

CONCLUSIONS

Since an increase in the elimination of genetically damaged cells by apoptosis could reduce the risk of cancer from exposure to radiation or other DNA damaging agents, this cellular sensitization for apoptosis may represent a novel adaptive response mechanism.

Quadrangular space syndrome associated with superficial radial sensory neuropathy

Compression of the axillary nerve in the quadrangular space is an unusual cause of pain and paresthesia of the upper extremity. In this report, the authors present a patient with a 1-year history of an undiagnosed axillary nerve compression associated with radial sensory neuropathy who improved after surgical decompression of the quadrangular space.

A prospective comparison of laparoscopic ultrasound vs intraoperative cholangiogram during laparoscopic cholecystectomy

BACKGROUND

The laparoscopic ultrasound (US) probe provides a new modality for evaluating biliary anatomy during laparoscopic cholecystectomy (LC).

METHODS

We performed a laparoscopic US examination in 65 patients without suspected common bile duct (CBD) stones prior to the performance of a laparoscopic cholangiogram (IOC). We then compared the cost, time required, surgeon's assessment of difficulty, and interpretations of findings.

RESULTS

There was a significant difference in the cost of US versus the cost of IOC ($362 +/- 12 versus $665 +/- 12; p < 0.05). Surgeons who had performed >10 US (EXP) were compared with those who had performed </=10 (NOV). There were significant differences between the EXP and NOV groups in ease of examination, visualization of biliary anatomy, and accuracy of measurement of the CBD.

CONCLUSIONS

The use of laparoscopic US for the accurate evaluation of the CBD and biliary anatomy requires that the surgeon has surpassed the learning curve, which we have defined as having performed >10 US exams.

New directions in type 2 diabetes mellitus: an update of current oral antidiabetic therapy

This article reviewed the relevant literature including published clinical trials and reviews on currently available oral hypoglycemic agents. Results showed that the benefits of glycemic control have been established through multiple clinical trials. Long-term control of blood glucose levels in type 1 and type 2 diabetic patients will decrease the incidence and prolong the time until progression of diabetic retinopathy, nephropathy, and neuropathy. Our increased understanding of the pathophysiology behind type 2 diabetes has led to the development of many new agents that are aimed at treating the underlying insulin resistance and relative insulinopenia. The sulfonylureas as a group have been used for many years and act by stimulating insulin secretion. They are useful alone or as combination therapy with insulin or another oral hypoglycemic agent. The biguanides act by decreasing hepatic glucose production and by increasing peripheral insulin sensitivity. The alpha-glucosidase inhibitors act nonsystemically by blocking the metabolism of digested polysaccharides and therefore lowering the amount of carbohydrate absorbed in a meal. Benzoic acid derivatives act in a manner similar to that of sulfonylureas by enhancing pancreatic insulin production. They offer a shorter duration of action, lowering the risk of hypoglycemia. The thiazolidinediones increase peripheral insulin sensitivity and are effective as both monotherapy and combination therapy. Oral hypoglycemic agents, when properly administered, are very effective in controlling type 2 diabetes and preventing long-term complications.

Developments in the therapeutic applications of bisphosphonates

The authors review the structural, pharmacologic, and clinical aspects of bisphosphonates, a class of drugs currently used to treat several disorders of bone and calcium metabolism. Pertinent literature on the bisphosphonates was reviewed with the help of a MEDLINE search and several bibliographies, including published clinical trials, monographs, and review articles. The bisphosphonates are analogs of pyrophosphate that, when given orally or intravenously, bind avidly to exposed bone mineral and disrupt bone turnover. These agents comprise three groups or generations, based on their potency and chemical structures. All three generations are effective in treating hypercalcemia, Paget's disease of bone, osteoporosis, and other disorders of accelerated bone turnover. The third-generation agents have the greatest potency and offer the promise of a convenient way to suppress or prevent osseous metastasis in patients with certain malignancies. As a group, these agents are well tolerated and, when administered correctly, rarely cause toxicity. The bisphosphonates are safe and effective agents for the treatment of disorders of accelerated bone turnover.

AR-R15896AR blocks the early NMDA-induced loss of MAP2 in primary cortical cultures

The low-affinity use-dependent N-methyl-D-aspartate (NMDA) receptor antagonist AR-R15896AR is neuroprotective in primary rat cortical cultures exposed to toxic concentrations of NMDA and reduces the magnitude of NMDA-triggered increases in [Ca2+]i. Here we show using fluorescence staining and measurements of microtubule-associated protein-2 (MAP2) levels, that AR-R15896AR inhibits the NMDA-induced loss of MAP2 that occurs within 2 min following NMDA exposure. Understanding the multiple, Ca(2+)-triggered intracellular events that occur following NMDA receptor stimulation is important to the development of safe and effective neuroprotective agents.

Diagnosis and staging of ovarian cancer: comparative values of Doppler and conventional US, CT, and MR imaging correlated with surgery and histopathologic analysis--report of the Radiology Diagnostic Oncology Group

PURPOSE

To determine the optimal imaging modality for diagnosis and staging of ovarian cancer.

MATERIALS AND METHODS

Two hundred eighty women suspected to have ovarian cancer were enrolled in a prospective study before surgery. Doppler ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging were used to evaluate the mass; conventional US, CT, and MR imaging were used to stage spread.

RESULTS

All three modalities had high accuracy (0.91) for the overall diagnosis of malignancy. In the ovaries, the accuracy of MR imaging (0.91) was higher than that of CT and significantly higher than that of Doppler US (0.78). In the extraovarian pelvis and in the abdomen, conventional US, CT, and MR imaging had similar accuracies (0.87-0.95). In differentiation of disease confined to the pelvis from abdominal spread, the specificity of conventional US (96%) was higher than that of CT and significantly higher than that of MR imaging (88%), whereas the sensitivities of MR imaging (98%) and CT (92%) were significantly higher than that of conventional US (75%).

CONCLUSION

MR imaging is superior to Doppler US and CT in diagnosis of malignant ovarian masses. There is little variation among conventional US, CT, and MR imaging as regards staging.

Effect of stent design on reduction of elastic recoil: a comparison via quantitative intravascular ultrasound

The increase in minimum lumen diameter achieved by coronary stent placement can be further enhanced by reducing the immediate recoil that occurs after stent deployment. The effect of various stent designs-flexible coils, slotted tubes, and a locking stent-on minimization of postdilation stent recoil was evaluated using an in vitro model of circumferential compression. The stents were expanded to 7 atm (3.82 +/- 0.02 mm); as pressure was reduced, lumen diameter and cross-sectional area (CSA) were determined by on-line intravascular ultrasound imaging (30 MHz) positioned inside the dilating balloon (n = 10-15 inflation-deflation cycles). Stent recoil was assessed by calculation of percent change in CSA from 7 atm to negative balloon pressure: -33.1 +/- 5.6% (GR-II) and -22.4 +/- 3.8% (Wiktor) in the coil stents; -20.0 +/- 4.2% (JJIS coronary), -8.4 +/- 2.6% (JJIS biliary), and -6.9 +/- 1.5% (Multilink) in the slotted tube stents; and -1.9 +/- 3.2% in the Navius ZR1 locking stent (P < 0.05 vs. Multilink, P < 0.0001 vs. others). A range of resistances to recoil is demonstrated by this model, with coil stent designs undergoing greater elastic recoil than slotted tube stent designs. The locking stent design demonstrated the greatest radial strength and the most reduction in elastic recoil.

Practice of coronary angioplasty in California in 1995 : comparison to 1989 and impact of coronary stenting

BACKGROUND

This study seeks to analyze changes in the practice of PTCA in California between 1989 and 1995 by use of the Office of Statewide Health Planning and Development (OSHPD) data set.

METHODS AND RESULTS

All hospital discharges in 1995 with a procedure code for PTCA or stent were identified. The 1995 PTCA data were compared with previously published data from 1989 obtained from the same database. The number of PTCAs performed increased by 49% between 1989 and 1995, from 24 883 to 37 118. The percentage of female patients increased from 29.8% to 32.7% (P=0.0001). The percentage of diabetics increased from 14.4% to 21.6% (P=0.0001) between 1989 and 1995. Procedures on patients with a principal diagnosis of acute myocardial infarction increased from 19.3% of all PTCAs in 1989 to 27.5% of PTCAs in 1995 (P=0.0001). In-hospital mortality increased from 1.4% in 1989 to 1.9% in 1995 (P=0.0001). There were 3087 admissions with stent placement in 1995. In-hospital mortality after stent placement was 0.9% (P=0.0001 versus PTCA). Patients undergoing PTCA in hospitals performing >400 PTCAs in 1995 had a 4% incidence of death or emergency bypass surgery compared with a 6% incidence when PTCAs were performed in hospitals performing </=400 PTCA in 1995 (P<0.0001). Patients undergoing stent implantation in hospitals performing >75 stent procedures in 1995 had a 1.3% incidence of death or emergency bypass compared with an incidence of 4% when the procedure was performed in a hospital performing </=75 stent placements in 1995 (P<0.0001).

CONCLUSIONS

The 1995 OSHPD data continue to suggest an inverse relationship between hospital PTCA and stent volume and adverse patient outcomes.