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PubMed1989

Kwashiorkor in North America.

The controversy regarding the relative importance of protein vs energy deficiency in the genesis of kwashiorkor has not been resolved by studies of protein-energy malnutrition (PEM) in developing countries. Cases of edematous PEM (n = 29) in North America on the other hand provide clear indications that protein deficiency is an essential prerequisite for the development of kwashiorkor and marasmic kwashiorkor. Energy intakes may vary from low to high and the main source of energy may be carbohydrate or fat. These findings are in keeping with experimental evidence that a low ratio of protein to energy disrupts the usual hypometabolic response to dietary deficiency and leads to hypoalbuminemia and consequent edema. Protein supplements should be a part of programs aimed at preventing kwashiorkor.

Anthropometry↗

PubMed2003

Antimicrobial susceptibility of community-acquired respiratory tract pathogens in North America in 1999-2000: findings of the PROTEKT surveillance study.

The PROTEKT surveillance study commenced in 1999 to examine the antimicrobial susceptibility of community-acquired respiratory pathogens. We report here the results from 2371 isolates collected during 2000 by North American centers (Canada, n = 7; USA, n = 8). Overall, 21.3% of pneumococci (n = 687) were penicillin G-resistant (Canada, 10.3%; USA, 32.6%). Corresponding rates of erythromycin resistance were 16.3% and 31.5%. Telithromycin inhibited all penicillin- and erythromycin-resistant isolates at < or =1 microg/ml. Among 612 Hemophilus influenzae isolates, 22.4% were beta-lactamase-positive. Antimicrobial susceptibility of H. influenzae varied between 82.4% (clarithromycin) and 100% (cefpodoxime, levofloxacin). Importantly, one isolate was found to be resistant to both moxifloxacin and ciprofloxacin. Most Moraxella catarrhalis isolates were highly susceptible to the antimicrobials tested, except ampicillin. All Streptococcus pyogenes isolates (n = 382) were penicillin-susceptible and 5.2% were non-susceptible to erythromycin. S. pyogenes showed cross-resistance to other macrolides yet remained inhibited by telithromycin at < or =0.5 microg/ml. Methicillin resistance among Staphylococcus aureus was common (19.9%), particularly in the USA. The PROTEKT study confirms the widespread prevalence of antimicrobial resistance among common respiratory pathogens in North America, and hence the need for continued surveillance to guide optimal empiric therapy for community-acquired respiratory tract infections.

Anti-Bacterial Agents↗

PubMed1993

Changes in the patterns of blood pressure treatment in North America from 1960-1990.

Seven North American surveys investigation a total of 241,725 hypertensives conducted between 1960-90 were reviewed with respect to their treatment status. In 1960 and 1970 nearly half of hypertensives were unaware of their condition and only 16% were treated and well-controlled. During the time period between 1970-1990 the proportion of the 'unaware' respondents declined to 16%, while the proportion of treated and well controlled patients increased to more than 40%. The proportion of those who are treated but the blood pressure fails to be controlled by the therapy to a satisfactory degree remained essentially unchanged, at around 16%. The proportion of those who are aware of their hypertension but are not treated shows a moderately decreasing trend, still representing 16% of all hypertensives in a recent Canadian survey. Although the handling of hypertension as a public health problem is largely successful, one third of patients still don't receive optimal therapy or is not treated at all.

Adolescent↗

PubMed1989

Spinal cord injury prevention in North America.

Traumatic spinal cord injury is accompanied by enormous physical, psychosocial and financial losses for the individual and society. The age group most affected by spinal cord injury are adolescents and young adults and the incidence appears to be rising in North America. In the past, efforts have been directed towards minimising the effects of the injury, optimising rehabilitation and searching for a cure. Only recently has it been acknowledged that spinal cord injuries are preventable disabilities. Spinal cord injury prevention programmes have begun to be developed in several regions of the United States and Canada. The authors contend that effective prevention programmes should be based on understanding and application of the developmental characteristics of the target population and should incorporate behavioural as well as cognitive components. A prototype programme that would integrate these aspects is described. The purpose of this article is to describe the application of one educational approach to the issue of spinal cord injury prevention in adolescents. The approach may be useful for nurses involved in health education programmes dealing with other high incidence health problems of this age group, such as pregnancy and substance abuse.

Accidents, Traffic↗

PubMed2003

Comparative activity and spectrum of broad-spectrum beta-lactams (cefepime, ceftazidime, ceftriaxone, piperacillin/tazobactam) tested against 12,295 staphylococci and streptococci: report from the SENTRY antimicrobial surveillance program (North America: 2001-2002).

A contemporary collection of 12,295 North American isolates (2001-2002) consisting of Staphylococcus aureus (50%), coagulase-negative staphylococci (12%), Streptococcus pneumoniae (24%), beta-hemolytic streptococci (12%), and viridans-group streptococci (2%) were tested against broad-spectrum beta-lactams (cefepime, ceftazidime, ceftriaxone, imipenem, piperacillin/tazobactam) and comparator agents using a reference broth microdilution method to determine their continued effectiveness for empiric antimicrobial therapy. All isolates were very susceptible to vancomycin, linezolid and quinupristin/dalfopristin (>98%). Oxacillin-susceptible staphylococci were also highly susceptible to the tested beta-lactams (>98%) with the exception of ceftazidime (93%). beta-hemolytic streptococci were exquisitely susceptible (>99%) to penicillin and all other agents except for clindamycin (94%) and erythromycin (81%). Viridans group streptococci were routinely less susceptible than were other streptococci. S. pneumoniae remained susceptible to most agents (>91%) with the exceptions of erythromycin (74%) and penicillin (69%). Among beta-lactams tested against S. pneumoniae, ceftriaxone and cefepime continued to be very active against penicillin-susceptible (>99%) and intermediate (>98%) strains, but less active (80% and 82%, respectively) against penicillin-resistant isolates. These findings confirm that the newer cephalosporins (cefepime and ceftriaxone) among broad-spectrum beta-lactam agents have a spectrum of activity that remains comprehensive for the commonly isolated Gram-positive pathogens.

Drug Resistance, Bacterial↗

PubMed1977

Comparative studies on immunity to EBV-associated antigens in NPC patients in North America, Tunisia, France and Hong Kong.

This study compared the relative antibody titers to EBV-related antigens in patients with nasopharyngeal carcinoma (NPC) and controls from a high-incidence (Hong Kong), an intermediate incidence (Tunisia), and two low-incidence (France, North America) areas to determine which of several EBV antibodies best differentiated NPC patients from controls. Antibodies measured include anti-virus capsid antigen (VCA), anti-early antigen (EA), anti-soluble antigen by complement-fixation (CF) and antibody-dependent lymphocyte cytotoxicity (ADLC). A matched pair analysis showed that significantly more NPC patients had higher VCA and EA but not CF or ADLC antibody titers than their matched cancer controls. The comparison of geometric mean titers between NPC cases and controls was more than seven-fold (816 vs 11.5) for EA antibody and more than three-fold (359.7 vs 95.4) for VCA anti-body (p less than 0.01). A two-fold difference was seen for CF antibody to soluble antigens (27.3 vs 12.9, p less than 0.01) and a three-fold difference (2657.7 vs 870.9, p less than 0.05) was observed for ADLC. Our finding of significant differences between NPC patients from four countries and their matched controls suggest that if EBV is the etiological agent of NPC in Chinese, it is quite likely to cause the majority of NPC cases in other ethnic groups living in other countries as well.

Antibodies, Viral↗

PubMed1998

Chlorinated hydrocarbon contaminants in polar bears from eastern Russia, North America, Greenland, and Svalbard: biomonitoring of Arctic pollution.

Adipose tissue samples from polar bears (Ursus maritimus) were obtained by necropsy or biopsy between the spring of 1989 to the spring of 1993 from Wrangel Island in Russia, most of the range of the bear in North America, eastern Greenland, and Svalbard. Samples were divided into 16 regions corresponding as much as possible to known stocks or management zones. Concentrations of dieldrin (DIEL), 4,4'-DDE (DDE), sum of 16 polychlorinated biphenyl congeners (sigma PCB), and sum of 11 chlordane-related compounds and metabolites (sigma CHL) were determined. In order to minimize the effect of age, only data for adults (320 bears age 5 years and older) was used to compare concentrations among regions. Concentrations of sigma PCB were 46% higher in adult males than females, and there was no significant trend with age. Concentrations of sigma CHL were 30% lower in adult males than females. Concentrations of sigma PCB, sigma CHL, and DDE in individual adult female bears were standardized to adult males using factors derived from the least-square means of each sex category, and geometric means of the standardized concentrations on a lipid weight basis were compared among regions. Median geometric mean standardized concentrations (lipid weight basis) and ranges among regions were as follows: sigma PCB, 5,942 (2,763-24,316) micrograms/kg; sigma CHL, 1,952 (727-4,632) micrograms/kg; DDE, 219 (52-560) micrograms/kg; DIEL, 157 (31-335) micrograms/kg. Geometric mean sigma PCB concentrations in bears from Svalbard, East Greenland, and the Arctic Ocean near Prince Patrick Island in Canada were similar (20,256-24,316 micrograms/kg) and significantly higher than most other areas. Atmospheric, oceanic, and ice transport, as well as ecological factors may contribute to these high concentrations of sigma PCB. sigma CHL was more uniformly distributed among regions than the other CHCs. Highest sigma CHL concentrations were found in southeastern Hudson Bay, which also had the highest DDE and DIEL concentrations. In general, concentrations of sigma CHL, DDE, and DIEL were higher in eastern than western regions, suggesting an influence of North American sources. Average sigma PCB concentrations in bears from the Canadian Arctic were similar to those in 1982-84, while average sigma CHL and DDE concentrations were 35-44% lower and DIEL was 90% lower. However, the significance of these temporal trends during the 1980s is not conclusive because of the problems of comparability of data.

Adipose Tissue↗

PubMedDate not supplied

Secondary glaucomas in the dog in North America.

OBJECTIVE: To determine the prevalence of secondary glaucomas in dogs associated with cataract formation, lens luxation or displacement, cataract surgery, uveitis, hyphema and intraocular neoplasia. METHODS: Information was obtained from the Veterinary Medical Data Base (VMDB) from all veterinary medical teaching hospitals in North America from March 1964 to March 2003. Secondary glaucomas were diagnosed at the same examination or after the primary diagnosis was made, and included those associated with cataract formation, lens luxation, cataract surgery, uveitis of unknown cause, hyphema of unknown cause, and intraocular neoplasia. The data were evaluated by decade, breed, gender and age of presentation. RESULTS: A total of 1 592 831 dogs were presented, and 9695 canine secondary glaucomas. Secondary glaucoma associated with cataract formation represented 81% of all the canine secondary glaucomas. Breeds (n = 7890 dogs) predisposed to secondary glaucoma and cataracts had an overall prevalence of 0.5%, but nearly 20% of all the cataractous dogs developed secondary glaucoma in at least one eye. For the years 1994-2003, these breeds included the American Cocker Spaniel; Boston Terrier; Toy, Miniature and Standard Poodle; English Springer Spaniel; Bichon Frise; and Labrador Retriever. The other forms of secondary glaucoma occurred less frequently, and included those glaucomas with lens luxation or displacement (779 dogs; 12.0%), postcataract surgery (528 dogs; 5.1%), with uveitis from unknown cause (399 dogs; 7.1%), with hyphema from unknown cause (117 dogs; 7.3%), and with intraocular neoplasia (19 dogs; 3.5%). The risk of the secondary glaucomas from 1984 to 2002 was highest after the intracapsular lens extraction (ICLE), less in the extracapsular technique (ECLE), and lowest for the phacoemulsification/phacofragmentation method. CONCLUSION: Prevalence of the canine secondary glaucomas ranges from 0.25% (1964-1973), 0.46% (1974-1983), 0.79% (1984-1993), to 0.80% (1994-2003) and are as frequent as the primary or breed-related glaucomas during these same time periods.

Animals↗

PubMed1990

A case of rabies in North America.

A 25-year-old man developed classical hydrophobic rabies 3 months after being bitten on the face. We present his involuntary movements on videotape and discuss the clinical and epidemiological features of rabies. Though rabies is seen in tropical countries commonly and in North America occasionally, recording of the clinical features is rare.

Adult↗

PubMed1999

The role of providers in implementation of the National Kidney Foundation-Dialysis Outcomes Quality Initiative: Fresenius Medical Care North America perspective.

This is a brief review of the history of utilization of quality indicators by a major dialysis provider and how those indicators have been modified in response to the National Kidney Foundation-Dialysis Outcomes Quality Initiative (NKF-DOQI). Fresenius Medical Care North America (FMCNA) has monitored adequacy of dialysis, anemia management, and nutrition therapy for a number of years, using a self-directed continuous quality improvement program. FMCNA supports the NKF-DOQI Guidelines and has used the DOQI as it continues to enhance its patient quality care program. Specific goals and action thresholds of that program are delineated.

Foundations↗

PubMed1985

Circulation of influenza viruses and paramyxoviruses in waterfowl originating from two different areas of North America.

Migratory waterfowl and shore birds harbour a wide range of influenza viruses, some of which have been implicated in influenza outbreaks in mammals and domestic birds. In the present study, a comparison was made of two marshalling areas for different migratory flyways of waterfowl in North America over a 6-8-year period. Virtually all known influenza subtypes were isolated and the predominant subtype changed from year to year. A marked difference between the two locations was that the predominant subtypes circulating were never the same, even though in both areas, most virus isolations were made from the same duck species (mallard duck). Isolations of paramyxovirus were characterized mainly as avian PMV-1.Viruses isolated from ducks included those antigenically related to viruses causing disease in birds and mammals, although the viruses did not necessarily appear in ducks immediately before they appeared in other species. For example, H5N2 isolates antigenically related to the virus causing severe disease outbreaks in chickens in the USA in 1983, were detected in ducks from both areas at different times (1976, 1980 and 1982). These studies indicate that ducks in different areas represent a continual source of orthomyxoviruses and paramyxoviruses of potential disease significance to other species.

Alberta↗

PubMed2006

Noninvasive versus histologic detection of gastric atrophy in a Hispanic population in North America.

BACKGROUND & AIMS: Cancer risk is directly correlated with the severity and extent of mucosal atrophy, making identification of atrophy a goal in cancer prevention programs. The aim of this study was to compare targeted histology with noninvasive testing for the identification of antral and/or corpus atrophy in North America. METHODS: In a cross-sectional study of a random sample of households, 8 gastric biopsy specimens were obtained from defined locations in the antrum and corpus. Biopsies were scored for the presence of Helicobacter pylori and gastric atrophy (defined as loss of normal glandular components). Atrophy was scored by using the Sydney system and a system based on the number and location of corpus biopsies with atrophy. Patients' sera were examined for pepsinogen I, pepsinogen II, and gastrin-17 (fasting and stimulated). RESULTS: One hundred eighty volunteers, approximately 30 per age group and ranging in age from 18-82 years, participated. There were 76 men. The overall weighted prevalence of a corpus atrophy was 4.7% (95% confidence interval, 2.3-7.0). There was a significant inverse relationship between the grade of corpus atrophy and the pepsinogen I/pepsinogen II ratio (R = -0.31, P < .01). We failed to confirm the usefulness of the proposed algorithm by using gastrin-17, H. pylori serology, and serum pepsinogens to categorize the gastric histology. The Sydney system underestimated the prevalence of corpus atrophy by approximately 25%. CONCLUSION: Noninvasive testing is both possible and practical by using pepsinogen assays for the identification of the precancerous condition of moderate to severe corpus atrophy in North American Hispanic patients.

Adolescent↗

PubMed2002

Polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxinlike polychlorinated biphenyls in sediments and mussels at three sites in the lower Great Lakes, North America.

Levels of contaminants including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho-substituted and mono-ortho-substituted dioxinlike polychlorinated biphenyls (DLPCBs) were determined in sediments and freshwater mussels (Dreissena spp. and Elliptio complanata) at three sites in the lower Great Lakes (North America). Impacts of mussel colonization on sediment quality were investigated by comparing contaminant levels in colonized sediment with levels in sediment in the same area that was not colonized, but exposed to similar environmental conditions. Significant impacts on contaminant levels of colonized sediment, compared to noncolonized sediment, were observed at two sites exhibiting high mussel population densities (Fort Erie, eastern Lake Erie, ON, Canada, 2.2 kg/m2 dry wt biomass, and Port Dalhousie, western Lake Ontario, Ontario, Canada, 6.1 kg/m2 dry wt biomass); these differences were not observed at a site with lower mussel densities (Bay of Quinte, eastern Lake Ontario, Ontario, Canada, 0.7 kg/m2). Total organic carbon and contaminant concentrations were statistically significantly greater in colonized sediment, compared to noncolonized sediment, at the two impacted sites. Areal estimates of PCDD/PCDF and DLPCB toxicity equivalents (TEQs) in mussel biomass at the three sites averaged 0.16% and 3.3%, respectively, of the TEQs in the top 3 cm of sediment, indicating that the sediments were the primary sink for contaminants. The observed differences between colonized and noncolonized sediment suggest that Dreissena are capable of influencing the chemical properties of sediment they colonize.

Animals↗

PubMed1998

Socioeconomic impact of otitis media in North America.

OBJECTIVE: Otitis media (OM) is a common and expensive disease with estimated cost to the health care system in the U.S.A. estimated at 3 to 4 billion dollars and to that of Canada at 600 million dollars per year. Despite the high prevalence rates reported in North America, there remains little censensus about which of the various treatment strategies (medical or surgical) is most clinically effective, which is most cost effective, or which has the most economic and societal impact. Few studies have been conducted comparing the various treatment strategies or analyzing outcome measurement of physiologic end-points relative to the various treatments and quality-of-life issues. This article addresses these problem areas and gives recommendations and guidelines for consideration in the treatment of OM, as well as a review of the literature available.

Canada↗

PubMed2003

Increase in the export of alkalinity from North America's largest river.

Chemical weathering and the subsequent export of carbonate alkalinity (HCO3- + CO3-2) from soils to rivers account for significant amounts of terrestrially sequestered atmospheric CO2. We show here that during the past half-century, the export of this alkalinity has increased dramatically from North America's largest river, the Mississippi. This increased export is in part the result of increased flow resulting from higher rainfall in the Mississippi basin. Subcatchment data from the Mississippi suggest that the increase in the export of alkalinity is also linked to amount and type of land cover. These observations have important implications for the potential management of carbon sequestration in the United States.

Atmosphere↗

PubMed1999

Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean

Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds from the northern tundra of Siberia towards North America across the Arctic Ocean (without landmark influences) were recorded by ship-based tracking radar studies in July and August. Field observations indicated that waders, including species such as Phalaropusfulicarius and Calidris melanotos, dominated, but also terns and skuas may have been involved. Analysis of flight directions in relation to the wind showed that these movements are not caused by wind drift. Assuming possible orientation principles based on celestial or geomagnetic cues, different flight trajectories across the Arctic Ocean were calculated: geographical loxodromes, sun compass routes, magnetic loxodromes and magnetoclinic routes. The probabilities of these four alternatives are evaluated on the basis of both the availability of required orientation cues and the predicted flight paths. This evaluation supports orientation along sun compass routes. Because of the longitudinal time displacement sun compass routes show gradually changing compass courses in close agreement with orthodromes. It is suggested that an important migration link between Siberia and North American stopover sites 1000-2500km apart across the Arctic Ocean has evolved based on sun compass orientation along orthodrome-like routes.

Journal Article↗

PubMed2003

NmcA carbapenem-hydrolyzing enzyme in Enterobacter cloacae in North America.

An imipenem-resistant Enterobacter cloacae isolate was recovered from the blood of a patient with a hematologic malignancy. Analytical isoelectric focusing, inhibitor studies, hydrolysis, induction assays, and molecular sequencing methods confirmed the presence of a NmcA carbapenem-hydrolyzing enzyme. This first report of NmcA detected in North America warrants further investigation into its distribution and clinical impact.

Adult↗

PubMed1997

Effect of recombinant human insulin-like growth factor-I on progression of ALS. A placebo-controlled study. The North America ALS/IGF-I Study Group.

The objective of this study was to investigate the safety and efficacy of recombinant human insulinlike growth factor-I (rhIGF-I) in the treatment of sporadic ALS. A double-blind, placebo-controlled, randomized study of 266 patients was conducted at eight centers in North America. Placebo or rhIGF-I (0.05 mg/kg/day or 0.10 mg/kg/day) was administered for 9 months. The primary outcome measure was disease symptom progression, assessed by the rate of change (per patient slope) in the Appel ALS rating scale total score. The Sickness Impact Profile (SIP), a patient-perceived, health-related quality of life assessment, was a secondary outcome variable. Progression of functional impairment in patients receiving high-dose (0.10 mg/kg/day) rhIGF-I was 26% slower than in patients receiving placebo (p = 0.01). The high-dose treatment group was less likely to terminate the study due to protocol-defined markers of disease symptom progression, and members in this group exhibited a slower decline in quality of life, as assessed by the SIP. Patients receiving 0.05 mg/kg/day of rhIGF-I exhibited trends similar to those associated with high-dose treatment, suggesting a dose-dependent response. The incidence of clinically significant adverse experiences was comparable among the three treatment groups. Recombinant human insulin-like growth factor-I slowed the progression of functional impairment and the decline in health-related quality of life in patients with ALS with no medically important adverse effects.

Amyotrophic Lateral Sclerosis↗