A snapshot of the status of problem-based learning in U. S. medical schools, 2003-04.

PURPOSE: Although the use of problem-based learning (PBL) is widespread in U.S. medical schools, its true prevalence is unknown. This study examined the prevalence of PBL in preclinical curricula. METHOD: In 2003, a Web-based questionnaire was sent to education deans or directors of medical education at the 123 Liaison Committee on Medical Education-accredited medical schools in the United States. The respondents indicated whether or not they were using PBL and what percentage of faculty-student contact hours in the preclinical years used PBL. RESULT: All 123 schools responded. Of them, 70% used PBL in the preclinical years. Of schools using PBL, 45% used it for less than 10% of their formal teaching, while 6% used it for more than half of their formal teaching. Of the 30% of schools not using PBL, 22% had used it in the past, and 2% had plans to incorporate it in the future. CONCLUSIONS: Use of PBL is widespread in the preclinical curricula of U.S. medical schools. That use is limited, however, since fewer than 6% of programs use it for more than 50% of their instruction.     

Activity of the enantiomers of 2-amino-5-phosphono-valeric acid as stereospecific antagonists of excitatory aminoacids

The (+) and (?) enantiomers of 2-amino-5-phosphono-valeric acid have been separated and tested as antagonists of aminoacid excitation of neurones in rat cerebral cortex. The compounds were applied by microiontophoresis. The (?)-isomer was about 8–10 times more active than the racemate in blocking responses to N-methyl-d-aspartate, and was better able to distinguish between N-methyl-d-aspartate and glutamate.The results support the concept of a distinct population of receptors for N-methyl-d-aspartate.     

A profile of U.S. asthma centers, 2006.

BACKGROUND: Asthma is a significant public health problem that results in 1.8 million annual emergency department (ED) visits. Many ED visits may be prevented with specialized asthma care. OBJECTIVE: To describe US asthma centers with a long-term goal of exploring their potential role in improving outcomes for ED patients with acute asthma. METHODS: We conducted initial online surveys in 2004. One survey identified asthma centers and their directors through reports by emergency medicine researchers and fellowship directors (allergy/immunology, pulmonary, and critical care) at US hospitals. A second survey asked asthma center directors to describe their asthma center. Follow-up surveys were conducted 2 years later in 2006. RESULTS: Eighty-seven (49%) of the 177 hospitals surveyed have asthma clinics. Although spirometry was available on the day of the visit at all asthma centers surveyed in 2006, only 21% (95% confidence interval, 11 %-34%) of sites reported that at least 90% of visits per week included a spirometry test. Only one quarter (26%; 95% confidence interval, 15%-40%) of asthma centers reported that at least 90% of patients undergo a skin or blood test for environmental allergens during 1 of their visits. Half of center directors (53%) were unsure of the approximate number of annual ED visits for acute asthma at their hospital. No significant measured changes were noted in asthma centers between 2004 and 2006. CONCLUSIONS: Asthma centers are heterogenous, with different services available. Although challenges remain, collaboration between EDs and asthma centers may contribute to improved asthma outcomes and merits further study.     

A comparison of the anticonvulsant potency of (+/-) 2-amino-5-phosphonopentanoic acid and (+/-) 2-amino-7-phosphonoheptanoic acid

Two ω-phosphonic α-amino carboxylic acids have been compared as antagonists of excitation due to N-methyl-D-aspartic acid or aspartic acid on rat cortical neurons and also against seizures induced by sound in DBA/2 mice, or seizures induced by N-methyl-D-aspartic acid or 3-mercaptopropionic acid in Swiss S mice. There was no significant difference in potency ratios of ( ± ) 2-amino-7-phosphono-heptanoic acid and ( ± ) 2-amino-5-phosphonopentanoic acid, comparing inhibition of excitation due to glutamic acid, N-methyl-D-aspartic acid or aspartic acid on single cortical neurons using 3 quantitative microiontophoretic techniques. Although not statistically significant, due possibly to the large variation observed from cell to cell, a greater mean potency (comparing ejection currents required to reduce excitatory responses by 50%) of 2-amino-7-phosphonoheptanoic acid relative to 2-amino-5-phosphono-pentanoic acid was seen in the case of aspartic acid and N-ethyl-D-aspartic acid antagonism (1.80 ± 0.38 for aspartic acid; 1.52 ± 0.35 for N-methyl-D-aspartic acid). The sequential stages of sound-induced seizures in DBA/2 mice are more potently suppressed by 2-amino-7-phosphonoheptanoic acid than by 2-amino-5-phosphonopentanoic acid, with a potency ratio of 6–12 for wild running or clonic seizures (using either intracerebroventricular or intraperitoneal administration). Against clonic seizures induced by N-methyl-D-aspartic acid or by 3-mercaptopropionic acid, the potency ratio 2-amino-7-phosphono-heptanoic acid: 2-amino-5-phosphonopentanoic acid is approximately 2.5.The greater relative potency of 2-amino-7-phosphonoheptanoic compared to 2-amino-5-phosphono-pentanoic acid against a variety of epileptic seizure manifestations may be interpreted in terms of a greater antagonist action at certain excitatory receptor sites.     

Fine particulate air pollution and mortality in 20 U.S. cities, 1987-1994

BACKGROUND: Air pollution in cities has been linked to increased rates of mortality and morbidity in developed and developing countries. Although these findings have helped lead to a tightening of air-quality standards, their validity with respect to public health has been questioned. METHODS: We assessed the effects of five major outdoor-air pollutants on daily mortality rates in 20 of the largest cities and metropolitan areas in the United States from 1987 to 1994. The pollutants were particulate matter that is less than 10 microm in aerodynamic diameter (PM10), ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide. We used a two-stage analytic approach that pooled data from multiple locations. RESULTS: After taking into account potential confounding by other pollutants, we found consistent evidence that the level of PM10 is associated with the rate of death from all causes and from cardiovascular and respiratory illnesses. The estimated increase in the relative rate of death from all causes was 0.51 percent (95 percent posterior interval, 0.07 to 0.93 percent) for each increase in the PM10 level of 10 microg per cubic meter. The estimated increase in the relative rate of death from cardiovascular and respiratory causes was 0.68 percent (95 percent posterior interval, 0.20 to 1.16 percent) for each increase in the PM10 level of 10 microg per cubic meter. There was weaker evidence that increases in ozone levels increased the relative rates of death during the summer, when ozone levels are highest, but not during the winter. Levels of the other pollutants were not significantly related to the mortality rate. CONCLUSIONS: There is consistent evidence that the levels of fine particulate matter in the air are associated with the risk of death from all causes and from cardiovascular and respiratory illnesses. These findings strengthen the rationale for controlling the levels of respirable particles in outdoor air.     

A comparison of the availability and content of genetic counseling as perceived by hemophilic men and carriers in the U.S.A., Canada, Scotland, and Greece

A survey study was carried out with 211 hemophilic men and 205 carriers of hemophilia at four hemophilia centers in New York; London, Ontario; the West of Scotland; and Athens, Greece. The participants responded to a questionnaire exploring socio-demographic and medical information, attitudes toward hemophilia, and experience of and attitudes toward genetic counseling. The study shows differences between attitudes of hemophilic men and carriers, differences in perceived problems among patients and carriers in the four centers, and differences in opinions between consumers and professionals. Comprehensive services for hemophilic families available in the New York center facilitate both patient education and satisfaction.     

Proficiency testing in immunohematology in Ontario, Canada, 1975-1977.

Since April 1975 the proficiency of laboratories in Ontario that perform immunohematology tests has been assessed. While the majority of test samples have required only ABO and Rh(D) typing, others have posed problems. The error rate in uncomplicated ABO typing was 1.3/1,000 in 17,479 tests and that in straightforward Rh(D) grouping, 6.6/1,000 in 17,757 tests. False-negative (36/1,000) and false-positive (1.4/1,000) direct antiglobulin tests occurred. Errors in detection of strong alloantibodies (e.g., anti-D) were 19.7, 10.2 and 5.1/1,000 in three test samples. A2B or A2 cells with anti-A1 in serum were sent out in two surveys; error rates in ABO interpretation were 189 and 52/1,000, respectively. Laboratories also experienced difficulty in interpreting the Rh(D) type of cells with positive antiglobulin tests. These surveys have had several effects: (1) laboratories with poor performance have been identified, (2) patterns of practice have been influenced, (3) areas of ignorance have been identified, and (4) a stimulus has been provided for continuing education in immunohematology.