Trends in the clinical and morphological characteristics of cardiac myxoma: 20-year experience of a single tertiary referral center in Japan.
(9/45)
The purpose of this study was to clarify whether or not a change in the clinical characteristics of cardiac myxoma has occurred during the past 2 decades. The clinical records of 57 patients (22 men, 35 women; age, 52+/-14 years) with myxoma that had been surgically treated between May 1978 and July 1997 at the National Cardiovascular Center in Japan were reviewed. All myxomas were discovered by transthoracic echocardiography. They were divided into an early group (n=30) treated in the first decade (1978-1987) and a late group (n=27) treated in the second decade (1988-1997). The incidence of myxoma, patient characteristics, preoperative symptoms and echocardiographic features did not differ between the 2 groups. In contrast, the maximal dimensions of myxoma in the early group were significantly larger than those in the late group (6.3 +/-2.7 cm vs 4.3+/-1.3 cm, p=0.012). The weight of myxoma in the early group tended to be heavier than that in the late group (76+/-80 g vs 25+/-18 g, p=0.054). The incidence of patients with asymptomatic myxoma also tended to increase in the late group (7% vs 26%, p=0.07). Although there was no difference in the incidence of myxoma, smaller and asymptomatic myxomas were more frequent during the last decade, probably as a result of the development of cardiac imaging, particularly echocardiography. (+info)
Evaluation of a method for typing the microsatellite D12S391 locus using a new primer pair and capillary electrophoresis.
(10/45)
We describe a modified method for typing a polymorphic microsatellite D12S391 locus by PCR using a newly designed primer pair. This primer pair produces shorter D12S391 amplified fragments (104-156 bp) than the primer pair originally described by Lareu et al. (209-261 bp). The detection system for the D12S391 locus using the new primer pair and capillary electrophoresis (CE) analysis was evaluated using various forensic samples. The typing results from 70 DNA samples using the new primer pair and the original primer pair were completely identical. One hundred twenty-five amplified fragments from D12S391 alleles were sized correctly within +/- 0.25 bp of the D12S391 allelic ladder. A rare allele, 19.3, previously found only in Caucasians, was found for the first time in a Japanese subject, and it was clearly distinguished from allele 20 by the CE analysis. This detection system was sensitive and could detect D12S391 types from 16 pg of genomic DNA, and from a minor component at a ratio of 1:10 in mixed samples. This system was more useful for the analysis of degraded DNA than was the method using the original primer pair, and could detect D12S391 types from bloodstains that had been stored for 26 years. In addition, the specificity of the method was demonstrated using nonhuman DNA. (+info)
Identification of severe acute respiratory syndrome in Canada.
(11/45)
BACKGROUND: Severe acute respiratory syndrome (SARS) is a condition of unknown cause that has recently been recognized in patients in Asia, North America, and Europe. This report summarizes the initial epidemiologic findings, clinical description, and diagnostic findings that followed the identification of SARS in Canada. METHODS: SARS was first identified in Canada in early March 2003. We collected epidemiologic, clinical, and diagnostic data from each of the first 10 cases prospectively as they were identified. Specimens from all cases were sent to local, provincial, national, and international laboratories for studies to identify an etiologic agent. RESULTS: The patients ranged from 24 to 78 years old; 60 percent were men. Transmission occurred only after close contact. The most common presenting symptoms were fever (in 100 percent of cases) and malaise (in 70 percent), followed by nonproductive cough (in 100 percent) and dyspnea (in 80 percent) associated with infiltrates on chest radiography (in 100 percent). Lymphopenia (in 89 percent of those for whom data were available), elevated lactate dehydrogenase levels (in 80 percent), elevated aspartate aminotransferase levels (in 78 percent), and elevated creatinine kinase levels (in 56 percent) were common. Empirical therapy most commonly included antibiotics, oseltamivir, and intravenous ribavirin. Mechanical ventilation was required in five patients. Three patients died, and five have had clinical improvement. The results of laboratory investigations were negative or not clinically significant except for the amplification of human metapneumovirus from respiratory specimens from five of nine patients and the isolation and amplification of a novel coronavirus from five of nine patients. In four cases both pathogens were isolated. CONCLUSIONS: SARS is a condition associated with substantial morbidity and mortality. It appears to be of viral origin, with patterns suggesting droplet or contact transmission. The role of human metapneumovirus, a novel coronavirus, or both requires further investigation. (+info)
Accelerator mass spectrometry at Arizona: geochronology of the climatic record and connections with the ocean.
(12/45)
There are many diverse uses of accelerator mass spectrometry (AMS). 14C studies at our laboratory include much research related to paleoclimate, with 14C as a tracer of past changes in environmental conditions as observed in corals, marine sediments, and many terrestrial records. Terrestrial records can also show the influence of oceanic oscillations, whether they are short term, such as ENSO (El Nino/Southern Oscillation), or on the millennial time scale. In tracer applications, we have developed the use of 129I as well as 14C as tracers for nuclear pollution studies around radioactive waste dump sites, in collaboration with IAEA. We discuss some applications carried out in Tucson, AZ, for several of these fields and hope to give some idea of the breadth of these studies. (+info)
Date of origin of the SARS coronavirus strains.
(13/45)
BACKGROUND: A new respiratory infectious epidemic, severe acute respiratory syndrome (SARS), broke out and spread throughout the world. By now the putative pathogen of SARS has been identified as a new coronavirus, a single positive-strand RNA virus. RNA viruses commonly have a high rate of genetic mutation. It is therefore important to know the mutation rate of the SARS coronavirus as it spreads through the population. Moreover, finding a date for the last common ancestor of SARS coronavirus strains would be useful for understanding the circumstances surrounding the emergence of the SARS pandemic and the rate at which SARS coronavirus diverge. METHODS: We propose a mathematical model to estimate the evolution rate of the SARS coronavirus genome and the time of the last common ancestor of the sequenced SARS strains. Under some common assumptions and justifiable simplifications, a few simple equations incorporating the evolution rate (K) and time of the last common ancestor of the strains (T0) can be deduced. We then implemented the least square method to estimate K and T0 from the dataset of sequences and corresponding times. Monte Carlo stimulation was employed to discuss the results. RESULTS: Based on 6 strains with accurate dates of host death, we estimated the time of the last common ancestor to be about August or September 2002, and the evolution rate to be about 0.16 base/day, that is, the SARS coronavirus would on average change a base every seven days. We validated our method by dividing the strains into two groups, which coincided with the results from comparative genomics. CONCLUSION: The applied method is simple to implement and avoid the difficulty and subjectivity of choosing the root of phylogenetic tree. Based on 6 strains with accurate date of host death, we estimated a time of the last common ancestor, which is coincident with epidemic investigations, and an evolution rate in the same range as that reported for the HIV-1 virus. (+info)
Scoring of radiographic progression in randomised clinical trials in ankylosing spondylitis: a preference for paired reading order.
(14/45)
OBJECTIVES: To describe the influence of the reading order (chronological v paired) on radiographic scoring results in ankylosing spondylitis. To investigate whether this method is sufficiently sensitive to change because paired reading is requested for establishing drug efficacy in clinical trials. METHODS: Films obtained from 166 patients (at baseline, 1 year, and 2 years) were scored by one observer, using the modified Stoke Ankylosing Spondylitis Spinal Score. Films were first scored chronologically, and were scored paired 6 months later. RESULTS: Chronological reading showed significantly more progression than paired reading both at 1 year (mean (SD) progression 1.3 (2.6) v 0.5 (2.4) units) and at 2 years (2.1 (3.9) v 1.0 (2.9) units); between-method difference: p<0.001 at 1 year, and p<0.001 at 2 years. After 1 year, progression (>0 units) was found in 35/166 (21%) patients after paired reading and in 55/166 (33%) after chronological reading. After 2 years, these figures were 50/166 (30%) and 68/166 (41%), respectively. Sample size calculations showed that 94 patients in each treatment arm are required in a randomised clinical trial (RCT) to provide sufficient statistical power to detect a difference in 2 year progression if films are scored paired. CONCLUSION: Reading with chronological time order is more sensitive to change than reading with paired time order, but paired reading is sufficiently sensitive to pick up change with a follow up of 2 years, resulting in an acceptable sample size for RCTs. (+info)
A historical chronology of teaching physiological sciences to medical students in Hungary.
(15/45)
Starting from the second half of the 18th century, a brief chronology of teaching medical physiology and pathophysiology in Hungary is given in this article. Even when the major milestones of this history are only identified, one can recognize several significant achivements that may inspire the present and coming generations to develope and enrich this inheritance of high values. These achivements involve--inter alia--influential scientific "schools" founded by eminent professors, outstanding institutions of basic medicine, recognition of the relevance of the integrative approach in medical education, close relationship between teaching and scientific research, high-standard theoretical and practical training, teaching based on excellent domestic and foreign textbooks, extensive international relationships and experience. (+info)
Date of first positive HIV test: reliability of information collected for HIV/AIDS surveillance in the United States.
(16/45)
OBJECTIVES: This study examined the reliability of the first positive HIV test date reported in the U.S. HIV/AIDS Reporting System (HARS). This date is essential to determine case counts for resource allocation for HIV treatment and prevention efforts. METHODS: The dates of first positive HIV tests reported by individuals with HIV in an interview survey conducted in 16 states (n=16,394, interviewed 1995-2002) were compared with the dates of HIV diagnosis reported to HARS. The percentage of agreement for the year of diagnosis and the weighed kappa (k) with 95% confidence intervals (CIs) was calculated. RESULTS: Self-reported year of diagnosis agreed with the year of diagnosis in HARS for 56% of date pairs (k=0.69; 95% CI 0.68, 0.70); 30% reported an earlier diagnosis year. Agreement differed by sex, age, race, exposure, and reason or place of testing (p<.01). Lower agreement was found when the self-reported diagnostic test was anonymous (k=0.57; 95% CI 0.52, 0.62) compared with confidential tests (k=0.66; 95% CI 0.64, 0.68). Lower agreement was also found for cases first reported with AIDS (k=0.58; 95% CI 0.55, 0.62) compared with cases first reported with HIV not AIDS (k=0.71; 95% CI 0.70, 0.73) as well as for participants interviewed three years or more after their HARS diagnosis date (k=0.55; 95% CI 0.52, 0.57) compared with those interviewed within one year (k=0.62; 95% CI 0.61, 0.63). More than 20% of participants in almost all groups, however, reported earlier diagnosis years than those recorded in HARS. CONCLUSION: As many as 30% of HIV diagnoses may have occurred earlier than recorded in HARS. Additional studies need to determine mechanisms to adequately capture diagnosis dates in HARS. (+info)