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PubMed1999

Rheumatic diseases in North America's indigenous peoples.

OBJECTIVES: There are at least 3 million North American Indians and Eskimos in North America. The epidemiology of rheumatic diseases in Native North Americans differs from that described for the remainder of the North American population. An enhanced understanding of rheumatic diseases in these indigenous people may provide valuable clues to the cause of these disorders and improve rheumatologic care. METHODS: The world literature was searched for all reports of rheumatic diseases in North American Indians and Eskimos. The reports were reviewed and the findings summarized by disease process. RESULTS: Many Native American groups have high prevalence rates of rheumatoid arthritis (RA), systemic lupus erythematosus, connective tissue diseases, and spondyloarthropathies. There appears to be a correlation between the pattern of rheumatic diseases in Native North Americans and the patterns of migration and ancestry. In general, Amerind Indians have increased rates of RA and connective tissue disease, while Na-Dene Indians and Eskimos have high rates of spondyloarthropathies. The RA seen in Native Americans is generally severe, seropositive, with an early age of onset, and frequent extraarticular manifestations. Many Native American groups have very high frequencies of the RA shared epitope. The majority of Native American and Eskimo groups also have high frequencies of HLA-B27, and some of the world's highest prevalence rates of spondyloarthropathies are described in these groups. Although some groups show a marked tendency to develop either Reiter's syndrome or ankylosing spondylitis, psoriatic and enteropathic arthritis are rare. CONCLUSIONS: The excess rheumatic disease seen in this population is most likely genetic in origin. Because of the combination of high rates of rheumatic disease and relative genetic homogeneity, Native North Americans represent a singular opportunity to study genetic contributions to rheumatic disease. For clinicians, the index of suspicion for rheumatic diseases in North American Indians and Eskimos should be high, and the severe disease and sometimes atypical presentations kept in mind.

Humans↗
PubMed2006

Contingent Pacific-Atlantic Ocean influence on multicentury wildfire synchrony over western North America.

Widespread synchronous wildfires driven by climatic variation, such as those that swept western North America during 1996, 2000, and 2002, can result in major environmental and societal impacts. Understanding relationships between continental-scale patterns of drought and modes of sea surface temperatures (SSTs) such as El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) may explain how interannual to multidecadal variability in SSTs drives fire at continental scales. We used local wildfire chronologies reconstructed from fire scars on tree rings across western North America and independent reconstructions of SST developed from tree-ring widths at other sites to examine the relationships of multicentury patterns of climate and fire synchrony. From 33,039 annually resolved fire-scar dates at 238 sites (the largest paleofire record yet assembled), we examined forest fires at regional and subcontinental scales. Since 1550 CE, drought and forest fires covaried across the West, but in a manner contingent on SST modes. During certain phases of ENSO and PDO, fire was synchronous within broad subregions and sometimes asynchronous among those regions. In contrast, fires were most commonly synchronous across the West during warm phases of the AMO. ENSO and PDO were the main drivers of high-frequency variation in fire (interannual to decadal), whereas the AMO conditionally changed the strength and spatial influence of ENSO and PDO on wildfire occurrence at multidecadal scales. A current warming trend in AMO suggests that we may expect an increase in widespread, synchronous fires across the western U.S. in coming decades.

Journal Article↗
PubMed2004

Is heart failure different on the two continents (North America and Europe)?

Heart failure is increasing in both North America and Europe. Although many similarities in the disease are apparent between the two continents, differences do exist. Heart failure with preserved systolic function appears to be increasingly important on both continents, and is associated more frequently with hypertension, aging, and female sex. Treatment guidelines from the two continents show more similarities than differences, though different treatment patterns emerge. Because more patients with heart failure will be older in the future, clinical trials that include greater numbers of these patients are needed to demonstrate that therapies are as effective and safe in this population.

Europe↗
PubMed1998

Human coenurosis in North America: case reports and review.

Coenurosis is a zoonotic disease of humans caused by the larval stage of Taenia (Multiceps) species. In North America, the adult tapeworm of Taenia (Multiceps) serialis is found in canids. The cystic larval forms (coenuri) are found in hares, rabbits, squirrels, and, rarely, in humans. We review in clinical detail the fifth case reported from North America, involving a child with extensive central nervous system involvement. We also report a sixth case, involving an adult with an intramuscular coenurus. The latter case was diagnosed by needle aspiration of the cyst. Although praziquantel administration may have been effective in killing the parasite in both patients, we are concerned about the production of marked inflammation as a result of treatment. The four other North American cases are reviewed, and the epidemiology of the infection in animals is discussed.

Adult↗
PubMed2002

Chronic wasting disease in deer and elk in North America.

Chronic wasting disease (CWD) has emerged as an important disease of wildlife in North America. The disease is a unique member of the transmissible spongiform encephalopathies (TSEs) or prion diseases, which naturally affect only a few species. Of the TSEs, CWD is the only one found in free-ranging species. However, interest in CWD has recently grown, by association with the better-known TSEs such as variant Creutzfeldt-Jakob disease of humans and bovine spongiform encephalopathy. Knowledge of the geographic distribution of CWD, though still limited, has greatly improved since the mid-1990s as a result of surveillance in free-ranging deer and elk and in commercially owned Rocky Mountain elk (Cervus elaphus nelsoni), and the disease has now been found in multiple areas of the plains and Rocky Mountain foothills of western North America. Studies of the biology and natural history of CWD over recent years have resulted in a better understanding of the pathogenesis and epidemiology of the disease. Early involvement of the lymphoid tissues of the alimentary tract during the incubation period of CWD suggests plausible routes for agent exit from an infected individual, such as in faeces or saliva. Chronic wasting disease is laterally transmitted and environmental contamination may play an important role in local maintenance of the disease. Studies on the epidemiology of CWD have led to the development of models to help explain the history of CWD and to simulate future impacts on deer and elk populations. Diagnostic tests have been improved, allowing diagnosis early in the incubation period, long before the appearance of clinical disease. Surveillance techniques and programmes have been developed and instituted by wildlife management agencies for free-ranging deer and elk and by state and federal agricultural agencies for privately-owned elk. During the 1990s, perceptions of TSEs have altered dramatically; perhaps most remarkably, the goal of global eradication of all prion diseases is now being discussed.

Animals↗
PubMed2003

Update on molecular epidemiology of H1, H5, and H7 influenza virus infections in poultry in North America.

Avian influenza is endemic in wild birds in North America, and the virus routinely has been transmitted from this reservoir to poultry. Influenza, once introduced into poultry, can become endemic within the poultry population. It may be successfully eradicated by human intervention, or the virus may fail to successfully spread on its own. In the last 5 yr, influenza virus has been isolated from poultry in the United States on numerous occasions, and, with the use of molecular epidemiology, the relationships of these different viruses can be determined. There are 15 different hemagglutinin subtypes of avian influenza viruses, but infections with virus of H5 and H7 subtypes are of the most concern because of the potential for these viruses to mutate to the highly pathogenic form of the virus. Most of the influenza isolations in the United States have been associated with the live-bird markets (LBMs) in the Northeast. This has included primarily H7N2 influenza viruses, but also H7N3, H5N2, and other subtypes. Most of the H7N2 viruses were part of a single lineage that was first observed in 1994, but new introductions of H7N2 and H7N3 were also observed. The predominant H7N2 LBM lineage of virus spread to large commercial poultry operations on at least three occasions since 1997, with the largest outbreak occurring in Virginia in 2002. The H5N2 viruses in the LBMs included viruses from domestic ducks, gamebirds, and environmental samples. Some H5N2 viruses isolated in different years and in different locations had a high degree of sequence relatedness, although the reservoir source, if it is endemic, has not been identified. Finally, an H1N2 virus, associated with a drop in egg production, was isolated from turkeys in Missouri in 1999. This virus was a complex reassortant with swine, human, and avian influenza genes that was similar to recent swine isolates from the Midwest. Additional serologic evidence suggests that flocks in other states were infected with a H1N2 virus.

Animals↗
PubMed1990

Epizootiology of neoplasms in bony fish of North America.

Over the past 25 years, there have been an increasing number of fish tumor epizootics recognized in discrete geographical areas in North America. This is consistent with an association between tumor development in fish and exposure to waterborne contaminants as a result of increased industrialization. Reports of fish tumor epizootics from the literature, plus acquisitions at the Registry of Tumors in Lower Animals, Smithsonian Institution originate from 41 geographical regions in North America. Epizootics of hemic, neural, connective tissue, and gonial neoplasms seem unrelated to environmental pollution, but epizootics of hepatic and epidermal neoplasms appear to be caused or strongly influenced by environmental pollution. The 14 species with epizootic liver tumors are all bottom feeding fish, and tumor-bearing fish are generally located in areas where chemical contaminants are concentrated. Epidermal neoplasms are also found in fish near polluted areas, but a direct cause-and-effect link with chemical carcinogens is not clear.

Animals↗
PubMed2006

Phylogeography of Pseudacris regilla (Anura: Hylidae) in western North America, with a proposal for a new taxonomic rearrangement.

The Baja California populations of Pseudacris regilla, a widespread species in Western North America ranging from British Columbia to southern Baja California, are characterized by extensive geographic fragmentation. We performed phylogeographic and historical demographic analyses on 609 bp of the cytochrome b mitochondrial gene of 110 individuals representing 28 populations to determine the relative influences of current and historical processes in shaping the present distribution of genetic diversity on the Baja California Peninsula. Haplotypes from this area were nested in a clade with three well-differentiated groups. Two of these groups are from Baja California Sur and another is from California and Baja California. The estimated date for the split of these groups, between 0.9-1 Ma, fits with previously proposed hypotheses of vicariance due to different transpeninsular seaways, although successive population fragmentation and expansion due to climatic oscillations during Pleistocene glaciations cannot be discarded. Historical demographic analyses detected signs of past population expansions, especially in the southernmost group. With respect to populations north of this region, two older clades were identified, one with haplotypes mainly distributed in central California, and the other corresponding to the northern half of the species range, in what apparently is a recurrent pattern in the Pacific coast of North America. Based on the concordance between mt-DNA and available allozyme data indicating that these species have a long independent evolutionary history, we propose to consider the three major clades as distinct species: P. regilla, P. pacifica, and P. hypochondriaca.

Animals↗
PubMed2005

Atmospheric distribution and long-range transport behavior of organochlorine pesticides in North America.

Annually averaged concentrations and enantiomeric compositions of organochlorine pesticides (OCPs) in air were determined in 2000/2001 at 40 stations across North America using XAD-based passive samplers. Absolute concentration differences acrossthe continent, the skewness and kurtosis of the concentration distribution, the relative abundance of parent compound and metabolites, and the chiral signatures can identify regional sources of OCP to the atmosphere. Specifically, air samples collected in the southeastern United States had elevated concentrations of chlordane-related compounds, higher ratios of trans- to cis-chlordane and heptachlor to heptachlor epoxide, as well as higher enantiomeric fractions of trans-chlordane as compared to other regions, suggesting continued release of microbially unprocessed chlordane to the regional atmosphere. Similarly, greatly elevated concentrations of p,p'-DDT, low relative abundance of the metabolite DDE, and a racemic composition of o,p'-DDT in samples from southern Mexico and Belize indicate recent use of DDT in these regions. Belize is also a potential source region for dieldrin. Reflecting its continued use in North America, endosulfan is now one of the most abundant and ubiquitous OCPs in the continental atmosphere. In contrast to these OCPs, air concentrations of penta- and hexachlorobenzene vary only by factors of 2-4 across the continent, reflecting a long atmospheric residence time and few primary sources. Atmospheric levels of the chlorobenzenes, alpha-endosulfan, and p,p'-DDE increase with elevation in the Canadian Rocky Mountains. Empirical travel distances for the OCPs derived from latitudinal concentration profiles are in good agreementwith model-derived indicators of long-range transport potential and, in particular, lead to a similar categorization of the OCPs. Large-scale passive air sampling networks are suitable for monitoring compliance with, and effectiveness of, regulatory control measures and for establishing experimentally the atmospheric long-range transport behavior of organic air pollutants.

Air Movements↗
PubMed2002

The emergence of novel swine influenza viruses in North America.

Since 1997, novel viruses of three different subtypes and five different genotypes have emerged as agents of influenza among pigs in North America. The appearance of these viruses is remarkable because there were no substantial changes in the overall epidemiology of swine influenza in the United States and Canada for over 60 years prior to this time. Viruses of the classical H1N1 lineage were virtually the exclusive cause of swine influenza from the time of their initial isolation in 1930 through 1998. Antigenic drift variants of these H1N1 viruses were isolated in 1991-1998, but a much more dramatic antigenic shift occurred with the emergence of H3N2 viruses in 1997-1998. In particular, H3N2 viruses with genes derived from human, swine and avian viruses have become a major cause of swine influenza in North America. In addition, H1N2 viruses that resulted from reassortment between the triple reassortant H3N2 viruses and classical H1N1 swine viruses have been isolated subsequently from pigs in at least six states. Finally, avian H4N6 viruses crossed the species barrier to infect pigs in Canada in 1999. Fortunately, these H4N6 viruses have not been isolated beyond their initial farm of origin. If these viruses spread more widely, they will represent another antigenic shift for our swine population, and could pose a threat to the world's human population. Research on these novel viruses may offer important clues to the genetic basis for interspecies transmission of influenza viruses.

Animals↗
PubMed2001

Synlophe in Ostertagia cf. kasakhstanica (Nematoda: Ostertagiinae), the minor morphotype of O. bisonis from western North America.

Ostertagia cf. kasakhstanica, the putative minor morphotype of the polymorphic ostertagiine O. bisonis, is reported in Bison bison from South Dakota. Descriptions of the synlophe and details of other diagnostic characters useful in identification and differentiation of this minor morphotype from other ostertagiines in wild and domestic ruminants from western North America are presented. Laterally, the cervical synlophe is consistent with Type Ib pattern among ostertagiines and is within the range of variation previously described for O. bisonis. Among recognized minor morphotypes of ostertagiines in wild and domestic ruminants from North America, O. kasakhstanica is distinct from O. kolchida, O. dikmansi, and O. arctica based on a tapering lateral synlophe. It is further distinguished from O. lyrata by the pattern of the cervical synlophe in the lateral field, structure of the genital cone and spicules, and dimensions of the esophageal valve. Although morphologically similar to T. davtiani/T. trifucata and T. boreoarcticus f. minor, it can be readily distinguished by the 2-1-2 bursal pattern, the structure of the spicules and genital cone, and the length of the esophageal valve. Ostertagia hisonis/O. cf. kasakhstanica circulates among pronghorn, mule deer, bison, and cattle in west-central North America.

Animals↗
PubMed2004

A short history of pediatric endocrinology in North America.

Pediatric endocrinology evolved as a subspecialty from the era of biochemical and metabolic clinical investigation led by John Howland, Edwards Park, and James Gamble at Johns Hopkins; Allan Butler at Boston University and Harvard University; Daniel Darrow at Yale University; and Irving McQuarrie at the University of Rochester and the University of Minnesota during the early 20th century. The father of the new subspecialty was Lawson Wilkins, a private pediatric practitioner in Baltimore, Maryland, who was invited by Dr. Edwards Park to establish an endocrine clinic at the Harriet Lane Home at Johns Hopkins in 1935. Dr. Wilkins managed his practice and the clinic until 1946, when, at the age of 52, he accepted a full-time position at the University. Dr. Nathan Talbot was invited to develop a pediatric endocrine clinic at Massachusetts General Hospital by Allan Butler in 1942. These units and their associated subspecialty training programs during the 1950s and 1960s provided the large majority of the second-generation pediatric endocrinologists who went on to establish endocrine subspecialty programs in university medical centers in North America as well as Europe and South America. Diabetes as a clinical pediatric discipline evolved in parallel from the early clinics of Elliott Joslin and Priscilla White in Boston, M.C. Hardin and Robert Jackson at the University of Iowa, George Guest at the University of Cincinnati Children's Hospital, and Alex Hartman at the St. Louis Children's Hospital. The Lawson Wilkins Pediatric Endocrine Society was founded in 1971, and the Council on Diabetes and Youth was established within the American Diabetes Association in 1980. Medical and economic factors led to increasing integration of pediatric diabetes and general endocrine care and training, and diabetes care now is a major activity within the subspecialty of pediatric endocrinology. The growth of pediatric endocrinology in North America has paralleled the growth of academic medicine during the past half-century. In 2002, there were 72 training programs in North America: 65 in the United States and seven in Canada. The endocrinology sub-board of the American Board of Pediatrics was established in 1978 to certify training and competence in endocrinology, including diabetes. By 2002, the board had certified 927 pediatric endocrinologists. Pediatric endocrine subspecialists during the past half-century have contributed major advances in our understanding of the ontogeny of endocrine systems and the diagnosis and treatment of fetal-perinatal endocrine disorders; newborn screening for endocrine and metabolic disorders; the physiology and therapies for disorders of sexual differentiation and pubertal maturation; the development of anthropometric standards for childhood growth and development; the characterization and physiology of hormone systems, including receptors and hormone actions; the molecular genetics of a number of congenital endocrine disorders and heritable endocrine diseases; development of pediatric endocrine diagnostics and reference standards; the pathophysiology and management of autoimmune endocrine disease; and development of a growing armamentarium of therapeutic agents for treatment of endocrine and metabolic diseases.

Animals↗
PubMed2000

Description and morphometric variability of Paranoplocephala serrata n. sp. (Cestoda: Anoplocephalidae) in collared lemmings (Dicrostonyx spp., Arvicolinae) from Arctic Siberia and North America.

We describe Paranoplocephala serrata n. sp. (Cestoda, Anoplocephalidae) from collared lemmings Dicrostonyx torquatus and D. groenlandicus (Arvicolinae, Rodentia) in Arctic Siberia and North America. The new species was recorded from the Yamal Peninsula (type-locality), Yana Delta, Kolyma Delta, Wrangel Island, Alaska and Victoria Island/Kent Peninsula (Northwest Territories). P. serrata n. sp. is characterised by a long, ribbon-like strobila, distinctly serrated segments, a small scolex, unilateral or infrequently alternating genital pores and testes confined to the antiporal part of the segment. It differs from the related species (Andrya bairdi, Parandrya feodorovi and Paranoplocephala manseri) by several morphological features, including the distribution of testes (several testes antiporal to ventral longitudinal osmoregulatory canal), structure of the cirrus-sac and vagina, and large eggs (0.053-0.068 mm in the type-material). The material of P. serrata n. sp. from North America differs from the Siberian material by the shorter cirrus-sac, smaller dimensions of the female reproductive organs, larger seminal receptacle and larger eggs. However, the statistical differences in the dimensions of reproductive organs mainly reflect the larger size of mature segments in Siberian specimens compared with North American specimens. The main diagnostic features, i.e. the size and form of scolex and suckers, number and distribution of testes, position of female glands, vagina/cirrus-sac ratio and morphology of reproductive organs, do not differ markedly between the Palaearctic and Nearctic specimens. According to the structure of the early-stage uterus, A. bairdi Schad, 1954 belongs to the genus Paranoplocephala. Parandrya Gulyaev & Chechulin, 1996 is probably a synonym of Paranoplocephala. A redescription is provided for Paranoplocephala bairdi n. comb.

Animals↗
PubMed1995

Distribution of the Ixodes ricinus-like ticks of eastern North America.

We analyzed the geographic distribution of the Ixodes ricinus-like ticks in eastern North America by comparing the mitochondrial 16S rDNA sequences of specimens sampled directly from the field during the 1990s. Two distinct lineages are evident. The southern clade includes ticks from the southeastern and middle-eastern regions of the United States. The range of the northern clade, which appears to have been restricted to the northeastern region until the mid-1900s, now extends throughout the northeastern and middle-eastern regions. These phyletic units correspond to northern and southern taxa that have previously been assigned specific status as Ixodes dammini and Ixodes scapularis, respectively. The expanding range of I. dammini appears to drive the present outbreaks of zoonotic disease in eastern North America that include Lyme disease and human babesiosis.

Animals↗
PubMed1991

The medicinal flora of Native North America: an analysis.

This paper describes an analysis of the plants of North America which have been used medicinally by Native North Americans. A method using regression residuals is developed for analyzing large quantities of data, divided into subgroups of varying sorts and sizes. The analysis shows that the medicinal species utilized by Native North Americans are distributed in a highly non-random fashion across subclasses and families as well as across groups defined in terms of growth habit and life pattern. This distribution makes sense in terms of both the defensive chemistry and the "complexity" of plants.

Humans↗
PubMed2003

Molecular phylogenetics of Houstonia (Rubiaceae): descending aneuploidy and breeding system evolution in the radiation of the lineage across North America.

Nuclear and chloroplast DNA sequence variation was used to infer evolutionary relationships within and among members of Houstonia (Rubiaceae) and other closely related genera in North America. Sequences from the internal transcribed spacer (ITS) of the nrDNA and a cpDNA intron in the trnL gene were used to reconstruct phylogenetic relationships of 30 species of Houstonia and closely related genera. The data suggest that the North American species of Houstonia are not monophyletic, but belong to the same lineage as Stenaria. The radiation of this lineage has been accompanied by changes in the basic chromosome number of the major clades through descending aneuploidy. This loss of chromosomes was also associated with northward colonization of North America. However, other characters, such as an annual versus perennial habit, heterostylous and homostylous breeding systems, and the evolution of self fertilization, seem to be labile throughout the lineage, originating multiple times throughout the evolutionary history of the lineage.

Aneuploidy↗
PubMedDate not supplied

Trends in incidence and prognosis of the histological subtypes of lung cancer in North America, Australia, New Zealand and Europe.

BACKGROUND: Since the incidence of the histological subtypes of lung cancer in industrialised countries has changed dramatically over the last two decades, we reviewed trends in the incidence and prognosis in North America, Australia, New Zealand and Europe, according to period of diagnosis and birth cohort and summarized explanations for changes in mortality. METHODS: Review of the literature based on a computerised search (Medline database 1966-2000). RESULTS: Although the incidence of lung cancer has been decreasing since the 1970s/1980s among men in North America, Australia, New Zealand and north-western Europe, the age-adjusted rate continues to increase among women in these countries, and among both men and women in southern and eastern Europe. These trends followed changes in smoking behaviour. The proportion of adenocarcinoma has been increasing over time; the most likely explanation is the shift to low-tar filter cigarettes during the 1960s and 1970s. Despite improvement in both the diagnosis and treatment, the overall prognosis for patients with non-small-cell lung cancer hardly improved over time. In contrast, the introduction and improvement of chemotherapy since the 1970s gave rise to an improvement in - only short-term (<2 years) - survival for patients with small-cell lung cancer. CONCLUSIONS: The epidemic of lung cancer is not over yet, especially in southern and eastern Europe. Except for short-term survival of small cell tumours, the prognosis for patients with lung cancer has not improved significantly.

Adult↗
PubMed2005

Attendance, drug use patterns, and referrals made from North America's first supervised injection facility.

BACKGROUND: North America's first government sanctioned supervised injection facility (SIF) was opened in Vancouver in response to the serious health and social consequences of injection drug use and the perseverance of committed advocates and drug user groups who demanded change. This analysis was conducted to describe the attendance, demographic characteristics, drug use patterns, and referrals made during the first 18 months of operation. METHODS: As part of the evaluation strategy for the SIF, information is collected through a comprehensive on-site database designed to track attendance and the daily activities within the facility. All users of the SIF must sign a waiver form and are then entered into a database using a unique identifier of their choice. This identifier is used at each subsequent visit to provide a prospective record of attendance, drug use, and interventions. RESULTS: From 10 March 2004 to 30 April 2005 inclusive, there were 4764 unique individuals who registered at the SIF. The facility successfully attracted a range of community injection drug users including women (23%) and members of the Aboriginal community (18%). Although heroin was used in 46% of all injections, cocaine was injected 37% of the time. There were 273 witnessed overdoses with no fatalities. During just 12 months of observation, 2171 individual referrals were made with the majority (37%) being referred for addiction counseling. INTERPRETATION: Vancouver's SIF has successfully been integrated into the community, has attracted a wide cross section of community injection drug users, has intervened in overdoses, and initiated over 2000 referrals to counseling and other support services. These findings should be useful for other settings considering SIF trials.

Acquired Immunodeficiency Syndrome↗