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PubMed2004

A survey of clinical practice of lung transplantation in North America.

OBJECTIVES: The clinical practice of lung transplantation (LT) varies widely among transplant centers. The objective of this study was to determine the practice patterns of North American lung transplant programs in specific areas that are considered controversial by most lung transplant practitioners. METHODS: The Transplant/Immunology Network of the American College of Chest Physicians (ACCP) designed a survey and distributed it through the ACCP using a Web-based survey tool. The survey was divided into the following two sections: (1) patient selection issues; and (2) posttransplant management. Additional questions were asked about graft preservation, retransplantation, and living donor operations. A single 64-question survey was sent to each lung transplant program in the United Sates registered in the United Network of Organ Sharing database as of September 2001 and to each of the five active Canadian programs. RESULTS: The survey was conducted in September and October 2002. Fifty of 65 active centers completed the survey, for a response rate of 77%. The data are presented in graphic format as a percentage of respondents. CONCLUSION: This survey provides a large, time-sensitive database summarizing the clinical practice of LT in North America. In general, the survey responses demonstrated a remarkable degree of consistency around patient selection criteria, but much greater variance in posttransplant management of lung transplant recipients. These findings may reflect the fact that a published selection criteria guideline exists, but no similar documents have been designed for postoperative management. Hopefully, postoperative areas with widely divergent approaches to management will foster future collaborative studies aimed at identifying the most appropriate practices.

Data Collection↗
PubMed1999

Common ancestry of Borrelia burgdorferi sensu lato strains from North America and Europe.

Ten atypical European Borrelia burgdorferi sensu lato (Borrelia spp. ) strains were genetically characterized, and the diversity was compared to that encountered among related Borrelia spp. from North America. Phylogenetic analyses of a limited region of the genome and of the whole genome extend existing knowledge about borrelial diversity reported earlier in Europe and the United States. Our results accord with the evidence that North American and European strains may have a common ancestry.

Borrelia burgdorferi Group↗
PubMed2001

A review of soybean (Glycine max) seed, pod, and flower mycofloras in North America, with methods and a key for identification of selected fungi.

A review of the fungi associated with soybean seeds, pods, or flowers was conducted in North America. Species of Deuteromycetes are the most common fungi in each of the soybean flower organs followed by the Ascomycetes and Phycomycetes which comprise about one-fourth of the total mycoflora. Eighty genera and about 135 or more species occur in seeds, pods, or flowers. With regard to numbers of taxa from separate mycofloras, 63 genera and about 108 or more species occur in seeds, 65 genera and about 88 or more species occur in pods, and 36 genera and approximately 47 or more species occur in flowers. Most of the fungi which occur in flowers can be cultured from pods, and the majority of those fungi occur in seeds. Methods for and a key are provided for the identification of the 30 most important selected fungi.

Ascomycota↗
PubMed2001

Distribution of mitochondrial DNA lineages among Native American tribes of Northeastern North America.

The mtDNA haplogroups of 185 individuals from Native American tribes in Northeast North America were determined. A subset of these individuals was analyzed by sequencing hypervariable segments I and II of the control region. The haplogroup frequency distributions of populations in the Northeast exhibit regional continuity that predates European contact. A large amount of gene flow has occurred between Siouan-and Algonquian-speaking groups, probably due to an Algonquian intrusion into the Northeast. The data also support both the Macro-Siouan hypothesis and a relatively recent intrusion of Northern Iroquoians into the Northeast. These conclusions are consistent with archaeological and linguistic evidence.

Canada↗
PubMed2006

Comparative phylogeography of the Veronica alpina complex in Europe and North America.

The Veronica alpina complex comprises eight species of alpine habitats over a wide range of mountain systems in the Northern Hemisphere. The occurrence of sympatric species in the European and North American mountain systems allowed us not only to investigate the effect of the ice ages on intraspecific phylogeographical patterns and genetic diversity in different continents of the Northern Hemisphere, but also to compare these patterns in closely related species. Plastid DNA trnL-F sequences and AFLP (amplified fragment length polymorphism) fingerprints were used to infer the phylogenetic history of the group and phylogeographical patterns within species. Hybrid origin of tetraploid eastern North American V. wormskjoldii from western North American V. nutans (= V. wormskjoldii s.l.) and Eurasian V. alpina is suggested. A number of phylogeographical groups have been found both in V. alpina from Europe and in V. nutans from western North America. Phylogeographical substructuring in the Alps is inferred for V. alpina but not for V. bellidioides, which is moreover characterized by an overall very low genetic diversity. Western North American V. cusickii is much more genetically diverse than its sympatric relative, V. nutans, an effect that is likely due to differences in the breeding system. Populations of V. nutans are differentiated into three groups, those from the Cascades and from the southern and the northern Rocky Mountains. Genetic diversity seems to be higher in the North American V. nutans than in the morphologically and ecologically similar European V. alpina. A possible scenario to explain this pattern is suggested.

Base Sequence↗
PubMed2004

Comparison of anthocyanin pigment and other phenolic compounds of Vaccinium membranaceum and Vaccinium ovatum native to the Pacific Northwest of North America.

Two huckleberry species, Vaccinium membranaceum and Vaccinium ovatum, native to Pacific Northwestern North America, were evaluated for their total, and individual, anthocyanin and polyphenolic compositions. Vaccinium ovatum had greater total anthocyanin (ACY), total phenolics (TP), oxygen radical absorbing capacity (ORAC), and ferric reducing antioxidant potential (FRAP) than did V. membranaceum. The pH and degrees Brix were also higher in V. ovatum. Berry extracts from each species were separated into three different fractions--anthocyanin, polyphenolic, and sugar/acid-by solid-phase extraction. The anthocyanin fractions of each species had the highest amount of ACY, TP, and antioxidant activity. Each species contained 15 anthocyanins (galactoside, glucoside, and arabinoside of delphinidin, cyanidin, petunidin, peonidin, and malvidin) but in different proportions. Their anthocyanin profiles were similar by high-performance liquid chromatography with photodiode array detection (LC-DAD) and high-performance liquid chromatography with photodiode array and mass spectrometry detections (LC-DAD-MS). Each species had a different polyphenolic profile. The polyphenolics of both species were mainly composed of cinnamic acid derivatives and flavonol glycosides. The major polyphenolic compound in V. membranaceum was neochlorogenic acid, and in V. ovatum, chlorogenic acid.

Anthocyanins↗
PubMed2002

Stripe rust of wheat and barley in North America: a retrospective historical review.

This retrospective review deals with the sequence of events and research progress on control of stripe rust of wheat and barley in North America. From the discovery of stripe rust in 1915, it documents the early years of stripe rust research, the 20-year hiatus when stripe rust was not considered important and research was almost nonexistent, the short period in the 1950s when stripe rust became prevalent in the central United States, and the severe epidemics in the West in the 1960s and the associated revival and expansion of research. Finally, it covers 1968 to 2001 when the earlier information was consolidated and combined with results of new research to enable prediction and control of stripe rust, especially in the West.

Basidiomycota↗
PubMed1987

Strategies for surveillance, prevention, and control of arbovirus diseases in western North America.

Present strategies for surveillance, prevention, and control of arbovirus diseases in western North America have been developed from more than 4 decades of epidemiological research and development of mosquito control technology. Methods of prediction of outbreaks remain imprecise, although our understanding of sources of variation associated with indicators used for prediction is improving. Well organized and funded systematic mosquito abatement remains the most effective method of prevention of human cases of mosquito-borne virus disease, although emergency methods must be employed when outbreaks are imminent. The development of information management systems technology, use of recent developments of sampling theory, and research on vector competency and related areas should permit much better precision in estimates of impending outbreaks.

Animals↗
PubMed2003

Metschnikowia vanudenii sp. nov. and Metschnikowia lachancei sp. nov., from flowers and associated insects in North America.

Two new species of the ascosporic yeast genus Metschnikowia were isolated from nectaries and associated muscoid flies of flowers from the common milkweed (Asclepias syriaca) in North America, and are described as Metschnikowia vanudenii [type strain=PYCC 4650(T)=CBS 9134(T)=NRRL Y-27243(T)=UWO(PS) 86A4.1(T)] and Metschnikowia lachancei [type strain=PYCC 4605(T)=CBS 9131(T)=NRRL Y-27242(T)=UWO(PS) 7ASB2.3(T)]. As with the previously described Metschnikowia gruessii, M. vanudenii has vegetative cells with an 'aeroplane' or cross-like configuration, produces ovoid chlamydospores and forms ellipsoidopedunculate asci with two acicular ascospores. Metschnikowia lachancei is distinguished from other Metschnikowia species by formation of club-shaped asci with 1-2 thick clavate ascospores. The phylogenetic positions of the proposed new species within Metschnikowia were determined from sequence analysis of the D1/D2 domain of 26S rDNA. The new species show low nuclear DNA relatedness with neighbouring taxa.

Animals↗
PubMedDate not supplied

Fusicoccum arbuti sp. nov. causing cankers on pacific madrone in western North America with notes on Fusicoccum dimidiatum, the correct name for Scytalidium dimidiatum and Nattrassia mangiferae.

Pacific madrone (Arbutus menziesii) is a broadleaf evergreen tree native to western North America that has been in decline for the past 30 years. A fungus has been isolated and was verified as the cause of cankers on dying trees. It was determined to belong in the genus Fusicoccum, an asexual state of Botryosphaeria. This genus in both its sexual and asexual states commonly causes canker diseases of deciduous woody plants. Using morphological and molecular data the fungus causing cankers on Pacific madrone is characterized, described and illustrated as a new species of Fusicoccum, F. arbuti D.F. Farr & M. Elliott sp. nov. No sexual state is known for F. arbuti. Evidence from the literature, cultures and specimens suggests that F. arbuti, often mistakenly identified as Nattrassia mangiferae, has been causing madrone canker since at least 1968. Authentic isolates of Nattrassia mangiferae as the synanamorph Scytalidium dimidiatum were sequenced and determined to be different from Fusicoccum arbuti and to belong in Botryosphaeria/Fusicoccum. In addition to molecular sequence data, the morphology of the pycnidial and arthric conidial states of Nattrassia mangiferae/ Scytalidium dimidiatum resembles that of Fusicoccum. Therefore the correct name for Nattrassia mangiferae and its numerous synonyms (Dothiorella mangiferae, Torula dimidata, Scytilidium dimidiatum, Fusicoccum eucalypti, Hendersonula toruloidea, H. cypria, Exosporina fawcetii, H. agathidia, and S. lignicola) is Fusicoccum dimidiatum (Penz.) D.F. Farr, comb. nov.

Ascomycota↗
PubMed1997

Risk factors for bacterial gill disease in young rainbow trout (Oncorhynchus mykiss) in North America.

A retrospective whole-population survey was used to investigate putative risk factors for bacterial gill disease (BGD) in young hatchery-reared rainbow trout in North America. Three sets of analyses were done. The first analysis included as cases all of the hatcheries in which there was at least one outbreak of BGD during the 2-year study interval, regardless of location of the outbreak in the hatchery. The case group for the second analysis was limited to hatcheries for which the BGD outbreak occurred inside the hatch house. The case group for the third analysis was limited to hatcheries for which the BGD outbreak occurred outside of the hatch house. For the logistic regression that combined all cases of BGD (regardless of location of the outbreak), there was a significant association between mortality from bacterial gill disease and previous experience with BGD outbreaks (odds ratio (OR) = 10.1; 95% confidence interval (CI) = 5.6, 18.2), being a commercial trout hatchery (OR = 5.2; 95% CI = 2.6, 10.4), and being a hatchery with an annual salmonid fish production of > 250,000 fish (OR = 2.9; 95% CI = 1.5, 5.7). For BGD outbreaks that occurred in the hatch house, the presence of fish in the hatch house water supply significantly increased the odds of an outbreak (OR = 5.3; 95% CI = 2.2, 12.6), as did the use of ultraviolet radiation to disinfect the hatch house water (OR = 7.5; 95% CI = 2.2, 25.8), previous experience with bacterial gill disease (OR = 19.3; 95% CI = 7.9, 46.8), and being a commercial hatchery (OR = 7.7; 95% CI = 3.2, 18.6). The odds of a BGD outbreak outside of the hatch house was significantly associated with previous experience with BGD (OR = 4.3; 95% CI = 2.2, 8.6) and with being a hatchery with an annual salmonid fish production > 50,000 pounds (OR = 2.5; 95% CI = 1.2, 5.1).

Animals↗
PubMed1993

Comparison of the post-Chernobyl 137Cs contamination of mushrooms from eastern Europe, Sweden, and North America.

A comparison was made of 134Cs and 137Cs contamination in fungi from eastern Europe and eastern North America. Mean activities of 25 Ukrainian, 6 Swedish, and 10 North American collections were 4,660, 9,750, and 205 Bq/kg (dry weight), respectively. Additional measurements were made on samples from the Moscow, southern Belarus, and Yugoslavia/Bulgaria regions. Activity values were found to vary by several orders of magnitude within all geographic areas, even for the same mushroom species. Significantly higher specific activities were observed in mycorrhizal species than in saprophytic and parasitic fungi. Unfortunately, many of the European mycorrhizal species considered as prized edibles contained unacceptably high levels of 137Cs (> 1,000 Bq/kg [dry weight]) and should be used sparingly as food. By contrast, no mushrooms collected in Ontario or northern Michigan exceeded 1,000 Bq of 137Cs per kg (dry weight). The excessive 137Cs contamination was evident in mushrooms from areas that had substantial fallout from the 1986 accident in reactor 4 at the Chernobyl nuclear power station. However, observations suggest that about 20% of the 137Cs in eastern Europe (Moscow area, Belarus, and Ukraine) is of non-Chernobyl origin.

Air Pollution, Radioactive↗
PubMed2002

Older adolescents with cancer in North America deficits in outcome and research.

In the two decades from the mid 1970s to the mid 1990s, the proportion of 5-year survivors among children in North America with cancer has increased nearly 40%. Advances in otherwise fatal leukemias, lymphomas, sarcomas, brain tumors, germ cell neoplasms and cancer of the kidney account for much of the improvement. Unfortunately, older adolescents have not fared as well. Their epidemiological, medical, physical, psychological and social needs remain largely unmet despite their age juxtaposition with younger patients whose outcomes have so much improved. In the United States and Canada, cancer in adolescents 15 to 19 years of age occurs at nearly twice the rate observed in 5 to 14 year-olds. Many of the types of cancer that occur in older adolescents are unique to this age group, and the pattern of distribution occurs at no other age interval. Overall, the cancers in older adolescents are more similar to the spectrum of cancer in children than to the common types of cancer in adults, but they are also distinctly different and require an age-specific approach. There is evidence of a lower degree in reduction in cancer mortality in the United States and Canada in this age range than in younger or older persons. Moreover, the disparity appears to be increasing. The improvement in 5-year survival from diagnosis of cancer from the mid 1970s to the early 1990s was lower than the rate of improvement in the younger age groups. Survival rates of older adolescents with cancer in the general population have not improved as much, especially in comparison with results of the national pediatric cooperative cancer groups. In the United States and Canada, only about 5% of 15 to 25 year-olds with cancer are entered onto clinical trials, in contrast to 60% to 65% of younger patients. Thus, cancer during adolescence and early adulthood has been relatively neglected and merits enhanced national research programs and resources.

Adolescent↗
PubMed1993

Molecular analysis of an allozyme cline: alcohol dehydrogenase in Drosophila melanogaster on the east coast of North America.

Clines may either be selectively maintained or be the by-product of nonadaptive processes related to population structure and history. Drosophila melanogaster populations on the east coast of North America show a latitudinal cline in the frequencies of two common electrophoretically distinguishable alleles at the alcohol dehydrogenase locus (Adh), designated Adh-S and Adh-F. This cline may either be adaptive or an artifact of a possible recent dual founding of North American D. melanogaster populations in which frequencies of Adh alleles differed between founder populations. By means of a high resolution restriction-mapping technique, we studied the distribution of 113 haplotypes derived from 44 polymorphic DNA markers within the Adh region in 1533 individuals from 25 populations throughout the cline. We found significant clinal differentiation at the polymorphism determining the mobility-difference causing amino acid replacement between Adh-F and Adh-S alleles. Hitchhiking was limited, despite extensive linkage disequilibrium, and other sites did not vary clinally. Such a pattern of differentiation implies that selection is responsible for the cline. To investigate whether selection acts only on the Adh-F/S site, we performed a "selective equivalence" test under the assumption that all variability within the specified allelic class is selectively neutral. This revealed selective equivalence among Adh-S-bearing haplotypes, whose frequencies showed no differentiation throughout the cline, implying high levels of frequency-homogenizing gene flow. Geographical heterogeneity among Adh-F-bearing haplotypes implied the action of selection on one or more additional variants in linkage disequilibrium with Adh-F. In a further study of a subset of the data (n = 1076 from 18 populations), we found a combined insertion/deletion polymorphism, designated delta 1, located in the 5' adult intron and in linkage disequilibrium with Adh-F, to show more marked clinal variation than Adh-F/S. Although the unequivocal identification of the precise target(s) of selection requires further study, we suggest that clinal selection may be acting epistatically on the Adh-F/S and delta 1 polymorphisms.

Alcohol Dehydrogenase↗
PubMed1999

Psychopathy across cultures: North America and Scotland compared.

Differences in the prevalence and presentation of psychopathic personality disorder between North America and Scotland were evaluated. R. D. Hare's (1991) Psychopathy Checklist--Revised ratings obtained from a sample of 2,067 North American male prisoners and forensic patients were compared with ratings obtained from 246 Scottish male prisoners. Item response theory methods were used to examine differences in the performance of items and to equate the scale across settings. The items had equal relevance to the description of psychopathic personality disorder in both settings; however, the Scottish prisoners had to have higher levels of the underlying latent trait before certain characteristics became apparent. The prevalence of the disorder appears to be lower in Scotland. Explanations for the observed differences in terms of enculturation, socialization, and migration are explored.

Adolescent↗
PubMed2005

Analysis of Salmonella spp. with resistance to extended-spectrum cephalosporins and fluoroquinolones isolated in North America and Latin America: report from the SENTRY Antimicrobial Surveillance Program (1997-2004).

Emerging antimicrobial-resistant Salmonella spp. requires increased efforts to appropriately test susceptibility. The SENTRY Antimicrobial Surveillance Program monitored Salmonella spp. and detected nalidixic acid-resistant strains with elevated fluoroquinolone minimum inhibitory concentration (MIC) results and strains with extended-spectrum beta-lactamase (ESBL) "phenotypes" over the last 8 years. A total of 786 stool and bloodstream isolates from North American and Latin American medical centers (2001-2003) were tested by reference broth microdilution methods. Genetic analysis was used to further characterize the resistance mechanisms. Twenty-one sites forwarded 89 (11.3%) nalidixic acid-resistant (MIC, > or =32 microg/mL) strains. Nineteen of these isolates were studied to determine mutations in the quinolone resistance-determining region (QRDR). Among the nalidixic acid-resistant Salmonella spp. isolates, fluoroquinolone MIC values were also elevated (8- to 32-fold) compared with "wild-type" strains. Ciprofloxacin and gatifloxacin (MIC(90), 0.5 microg/mL) were more potent than levofloxacin and garenoxacin (1 microg/mL) against nalidixic acid-resistant strains. Single gyrA mutations were responsible for elevated fluoroquinolone MIC values and included D87Y (5), S83F (7), D87N (5), and S83Y (2). During 2001, 9 sites contributed 11 (2.9%) strains that met ESBL screening criteria (> or =2 microg/mL) for aztreonam or ceftazidime or ceftriaxone. ESBL confirmation was evaluated by Etest (AB BIODISK, Solna, Sweden) ESBL strips and the enzymes were characterized by polymerase chain reaction and gene sequencing. The ESBL phenotype isolates had the following MIC patterns: ceftazidime (> or =16 microg/mL), aztreonam (4 to >16 microg/mL), and ceftriaxone (8-32 microg/mL). All strains were susceptible to cefepime, carbapenems, gentamicin, and fluoroquinolones. No strains were inhibited by clavulanic acid consistent with all isolates producing the identified CMY-2, AmpC-like enzyme. Fluoroquinolones may be compromised among isolates with QRDR mutations detected using nalidixic acid as a screening agent. Salmonella spp. with ESBL phenotypes were likely to harbor CMY-2 (not an ESBL) and remain susceptible to cefepime, carbapenems, and fluoroquinolones, which can be used for serious invasive Salmonella spp. infections. Compared with the stool culture isolates, the blood culture isolates had higher QRDR mutations, but remained susceptible to the fluoroquinolones. The blood culture isolates were more susceptible to penicillins (ampicillin and ticarcillin) and not significantly different for ceftriaxone or trimethoprim/sulfamethoxazole susceptibility patterns. No QRDR trends over time were detected in North America, but increased resistance was observed in Latin America.

Anti-Bacterial Agents↗
PubMed2003

Studies of radon and lung cancer in North America and China.

Studies of radon-exposed underground miners indicate that residential radon is the second leading cause of lung cancer. Seven case-control studies of residential radon have been conducted in North America and two in China, and represent all studies in these areas which included 200 or more lung cancer cases and used long-term radon detectors. North American studies enrolled 4081 cases and 5281 controls, and Chinese studies enrolled 1076 cases and 2015 controls. Based on analyses of pooled data, odds ratios (ORs) and 95% confidence limits at 100 Bq m(-3) were 1.106 (1.00,1.28) for the North American studies and 1.139 (1.01,1.37) for the Chinese studies. Tests of homogeneity of ORs within populations were not significant. Among subjects with complete dosimetry for the 5-30 y exposure period prior to interview, ORs at 100 Bq m(-3) were 1.205 (1.03,1.50) for the North American studies and 1.279 (1.07,0.75) for the Chinese studies. Results are consistent with extrapolations from miners and indicate an excess lung cancer risk from residential radon.

Air Pollution, Indoor↗
PubMed2006

Aspidoderidae from North America, with the description of a new species of Aspidodera (Nematoda: Heterakoidea).

Aspidodera sogandaresi n. sp. (Heterakoidea: Aspidoderidae) from Dasypus novemcinctus Linnaeus, 1758 is herein described. This nematode occurs in armadillos from as far south as the canal zone of Panama, north through central Mexico, and into the southern United States. Previously identified as Aspidodera fasciata (Schneider, 1866), this new species has blunt projections on the lips and lateral expansions at the distal tips of the spicules, whereas A. fasciata has conspicuous digitiform projections on the lips, and a terminal round expansion at the tips of the spicules. Other species of the family present in North America include Aspidodera binansata Railliet and Henry, 1913; Aspidodera vazi Proença, 1937; and Lauroia trinidadensis Cameron, 1939.

Animals↗