American Population Groups Research Articles

Increased prevalence of valgus constitutional alignment subtypes in a South African arthritic population group using the coronal plane alignment of the knee (CPAK) classification

BackgroundKnee alignment philosophies and patient specific models to improve patient reported outcomes are gaining increasing attention. The coronal plane alignment of the knee (CPAK) classification describes nine knee phenotypes and then proposes surgical alignment strategies to achieve constitutional alignment. The CPAK classification has been validated in Australian, European, Asian and North American population groups. To date no African data has been analyzed using CPAK. MethodsA total of 344 arthritic patients (608 knees) with appropriate long leg radiographs were classified based on the CPAK type. Measurements included mechanical hip-knee-angle(mHKA), medial proximal tibial angle (mMPTA) and lateral distal femoral angle (mLDFA) and the derived calculations of joint line obliquity (JLO) and arithmetic hip-knee-angle (aHKA). ResultsThe sample population was 77.9% (n = 268) female with a mean age of 68.4 ± 9.2 years. The most common CPAK types in order were type 3 (n = 174; 28.6%), type 2 (n = 155; 25.5%), type 1 (n = 94; 15.5%) and type 6 (n = 80; 13.2%). The most common limb alignment types were valgus (CPAK types 3,6,9; 41.8%). ConclusionThis study, which investigated arthritic patients from a single institution in South Africa, shows a divergence of CPAK phenotypic knee patterns relative to other international studies, with much higher proportions of valgus phenotypes (3 and 6). This regional difference should be further investigated in other South African and African population samples and used to adapt the surgical strategies employed by local surgeons.

What Are We Really Estimating in Forensic Anthropological Practice, Population Affinity or Ancestry?

While American forensic anthropologists often state that they estimate ancestry, is that what they are really estimating? Although typological terminology, the oids, was replaced with continental terminology, the change was linguistic rather than substantive. The American population is comprised largely of immigrants. Genetic data suggests a high degree of admixture within American population groups. Further, data from documented skeletal collections suggest that Americans have undergone secular changes. Our paper addresses the uniqueness of the American population as compared to ancestral continental and geographic origin groups to address what it is that forensic anthropologists are really estimating, ancestry or something else? We conclude, based on uniqueness of American population groups, that what forensic anthropologists are estimating is best described as affinity, a term that indicates similarity and is not exclusively attached to definitions of race and ethnicity.

Performance of ancestry-informative SNP and microhaplotype markers

The use of microhaplotypes (MHs) for ancestry inference has added to an increasing number of ancestry-informative markers (AIMs) for forensic application that includes autosomal single nucleotide polymorphisms (SNPs) and insertions/deletions (indels). This study compares bi-allelic and tri-allelic SNPs as well as MH markers for their ability to differentiate African, European, South Asian, East Asian, and American population groups from the 1000 Genomes Phase 3 database. A range of well-established metrics were applied to rank each marker according to the population differentiation potential they measured. These comprised: absolute allele frequency differences (δ); Rosenberg’s informativeness for (ancestry) assignment (In); the fixation index (FST); and the effective number of alleles (Ae). A panel consisting of all three marker types resulted in the lowest mean divergence per population per individual (MDPI = 2.16%) when selected by In. However, when marker types were not mixed, MHs were the highest performing markers by most metrics (MDPI < 4%) for differentiation between the five continental populations.

Geographic patterns of end-stage renal disease and kidney transplants in the Midwestern United States

This research analyzes geographic patterns of ESRD incidence and kidney transplantation at county level in an area that covers 11 states in the Midwestern US from 2004 to 2011. We investigate whether variations in ESRD incidence exist among white, black, and Native American population groups, and the degree to which disparities existed with respect to access to kidney transplantation, and with respect to rural and urban counties. Spatial clusters of ESRD incidence rates are detected using global Moran's I and local Getis-Ord Gi∗ statistic. Spatial accessibility to transplant centers is evaluated using the enhanced two-step floating catchment area method where dissimilarities due to varying travel times and ESRD incidence rates result in differences in spatial access among the groups. Results show that while similar age-adjusted ESRD incidence rates hold for white and black population groups in urban counties, the kidney transplant rate is 73% lower among black patients than for whites in the study area. A lack of transplant centers in locations that correspond to strongly clustered age-adjusted ESRD incidence rates in southern Missouri and central South Dakota, contribute to lower spatial access indices in these counties. The results of the analyses capture varying patterns of ESRD incidence rates and kidney transplants in this Midwestern region and highlight spatial disparities for certain population groups.

Oceanographic influences on patterns in North Pacific salmon abundance

We identified three dominant patterns of temporal variation (1951–2002) in the abundance of 34 stock groups of wild North American and Asian pink salmon (Oncorhynchus gorbuscha), chum salmon (Oncorhynchus keta), and sockeye salmon (Oncorhynchus nerka) that were related to patterns of oceanographic variability. We identified these patterns using three different ordination methods and found consistent patterns across these methods. Alaskan salmon dominated the most prominent pattern, which exhibited a positive abundance shift in the mid-1970s. In general, warm (cold) periods in the Gulf of Alaska and eastern Bering Sea corresponded with high (low) abundance years for these stock groups. The second abundance pattern captured differences among Asian, northern North American, and southern North American population groups and was associated with an intense, large-scale Aleutian Low. To our knowledge, this is the first analysis that identifies regional patterns of covariation in salmon abundance around the entire North Pacific Rim, and it highlights the existence of basin-wide covariations in wild salmon abundance that are associated with spatially coherent and regionally distinct patterns in North Pacific climate.

Early Childhood Dental Caries: A Rising Dental Public Health Crisis

The aim of this article is to examine the literature and review the risk factors and disparities contributing to early childhood caries (ECC), which is a major health problem among preschoolers in the United States of America. A search was conducted using MEDLINE, PubMed, Google Scholar, and the Cochrane Library databases and the key terms ‘early childhood caries’, ‘baby bottle tooth decay’, ‘nursing caries’, ‘dental caries’, and ‘access to dental care and disparities’. ECC is a multifactorial disease with risk factors like biological, social, environmental, dietary and cultural determinants. Prevalence of ECC is highest among disadvantaged children living in poverty and in high-risk North American population groups such as, American Indians, Mexican Americans and in Hispanics. It is also found in families with less education and who have limited access to dental care services. This summarized review of early childhood caries will determine the need of future intervention programs focusing on the underserved and disadvantaged section of the population to prevent ECC.

Twelve short tandem repeat loci Y chromosome haplotypes: Genetic analysis on populations residing in North America

A total of 2443 male individuals, previously typed for the 13 CODIS STR loci, distributed across the five North American population groups African American, Asian, Caucasian, Hispanic, and Native American were typed for the Y-STR loci DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 using the PowerPlex ® Y System. All population samples were highly polymorphic for the 12 Y-STR loci with the marker DYS385a/b being the most polymorphic across all sample populations. The Native American population groups demonstrated the lowest genetic diversity, most notably at the DYS393 and DYS437 loci. Almost all of the 12-locus haplotypes observed in the sample populations were represented only once in the database. Haplotype diversities were greater than 99.6% for the African Americans, Caucasians, Hispanics, and Asians. The Native Americans had the lowest haplotype diversities (Apaches, 97.0%; Navajo, 98.1%). Population substructure effects were greater for Y-haplotypes, compared with that for the autosomal loci. For the apportionment of variance for the 12 Y-STRs, the within sample population variation was the largest component (>98% for each major population group and approximately 97% in Native Americans), and the variance component contributed by the major population groups was less than the individual component, but much greater than among sample populations within a major group (11.79% versus 1.02% for African Americans/Caucasians/Hispanics and 15.35% versus 1.25% for all five major populations). When each major population is analyzed individually, the R ST values were low but showed significant among group heterogeneity. In 692 confirmed father–son pairs, 14 mutation events were observed with the average rate of 1.57 × 10 −3/locus/generation (a 95% confidence bound of 0.83 × 10 −3 to 2.69 × 10 −3). Since the Y-STR loci reside on the non-recombining region of the Y chromosome, the counting method is one approach suggested for conveying an estimate of the rarity of the Y-haplotype. Because the Y-STR loci are not all in disequilibrium to the same extent, the counting method is a very conservative approach. The data also support that autosomal STR frequencies can be multiplied by the upper bound frequency estimate of a Y-haplotype in the individual population group or those pooled into major population groups (i.e., Caucasian, African American, Hispanic, and Asian). These analyses support use of the haplotype population data for estimating Y-STR profile frequencies for populations residing in North America.

Population Data of Five Genetic Markers in the Turkish Population: Comparison with Four American Population Groups

In this study, the phenotype and allele frequencies of five enzyme systems were determined in a total of 611 unrelated Turkish individuals and analyzed by using the exact and the chi 2 test. The following five red cell enzymes were identified by cellulose acetate electrophoresis: phosphoglucomutase (PGM), adenosine deaminase (ADA), phosphoglucose isomerase (PGI), adenylate kinase (AK), and 6-phosphogluconate dehydrogenase (6-PGD). The ADA, PGM and AK enzymes were found to be polymorphic in the Turkish population. The results of the statistical analysis showed, that the phenotype frequencies of the five enzyme under study are in Hardy-Weinberg equilibrium. Statistical analysis was performed in order to examine whether there are significant differences in the phenotype frequencies between the Turkish population and four American population groups. This analysis showed, that there are some statistically significant differences between the Turkish and the other groups. Moreover, the observed phenotype and allele frequencies were compared with those obtained in other population groups of Turkey.

Child abuse and neglect in American Indian communities

Child abuse and neglect have recently been found to occur among American Indians at rates comparable to other American population groups. Little is known about the clinical spectrum of Indian maltreatment, the psychodynamics and effective treatment modalities. Cultural misunderstanding, modernization, poverty, situational stress, poor parenting skills because of early break-up of Indian families, alcoholism, unusual perceptions of children, handicapped children, and divorce constitute factors associated with maltreatment in cases cited. Old solutions of removing children from families were largely inappropriate and ineffective and are being replaced by local efforts to develop foster homes, supportive family services, and legal procedures to protect children. Communication between agencies involved and mistrust of outsiders plus a lack of trained personnel and available community resources continue to pose major barriers to effective treatment and prevention efforts. Recent federal policies and laws clearly place the responsibility for child welfare in the hands of Indian tribes and tribal courts. The non-Indian health professional has an important but limited role in providing technical expertise and in aiding development of community resources, taking care to support but not usurp the emerging leadership of Indian people.

Influenza virus C infection in England.

In 1947 virus was isolated by Taylor (1949) from the throat washings of a man in New York who was suffer ing from a mild influenzal illness. It resembled the influenza viruses but differed from types A and B antigenically. Francis et al. (1950) later reported the recovery of a similar organism from the throat of a patient also suffering from an influenzal illness, and found serological evidence of infection in a number of other They suggested that the new virus be known as influenza virus Type C, and this designation has been generally accepted (Taylor, 1951 ; W.H.O., 1953). Isolations of influenza virus C have since been re ported from other laboratories in the United States (Gerber et al., 1952; DeMeio et al., 1955) and from Japan (Fukumi et al., 1951) and Czechoslovakia (Styk, 1954). However, few illnesses accompanied by an increase in antibody to this virus have been reported, and Minuse et al. (1954), commenting on experience at Ann Arbor, Michigan, stated that continued search has yielded only a few additional cases. Studies of the distribu tion of antibody to influenza virus C in American popu lation groups were made by Hilleman et al. (1953) and Davenport et al. (1953). These surveys showed a sharp rise in the general level of antibody during childhood, particularly in the earlier years. It seems probable that, in the United States, influenza virus C infection occurs widely in young children and may be accompanied by minor respiratory illness. Our own findings and those of Grist (1955) suggest that the same may be true in Britain. In the course of a number of investigations during the past three years we have had an opportunity to make clinical and laboratory observations on the presence of influenza virus C infection in this country. Histories of illness were studied in persons whose sera showed anti body changes, and sera from these investigations were used to estimate the age distribution of antibody in the population. Cases of influenza virus C infection were found during three investigations. In the winter of 1952-3, 455 factory workers who had volunteered for an influenza vaccine trial were under observation in Luton, Bedfordshire (McDonald and Andrews, 1955). Eighty two persons with an acute respiratory illness causing absence from work were visited at home. Specimens were-taken from 63 of them for laboratory examination, and serological evidence of virus C infection was found in one (Table-Case 1). In the following winter approxi mately 50 volunteers from each of five factories in widely separated parts of the country were bled at monthly intervals and their respiratory illnesses noted. Evidence of infection was found in one volunteer (Table -Case 2). In a study of 25 families in Wembley, Middlesex, between November, 1953, and April, 1955, a clinical record of all respiratory illnesses was kept, and blood taken from the adult members at approximately three-monthly intervals. Throat swabs or throat wash ings for virus isolation were obtained in all febrile illnesses, and in adults additional blood specimens were taken to provide paired sera for any such illness. Laboratory evidence indicated that influenza virus C infection occurred in eight persons during this study (Table-Cases 3 to 10).

Characteristics and Differential Fertility of American Population Groups

I885 to i889. The number of men concerned is of course small. It is also possible that failures to record children who died soon after birth were more common in the earlier records than now. Yet in spite of this there can be little question that the increase in families shown by these statistics is real. It confirms our other data in suggesting that the diminution in families arising from birth control has run its course among these distinguished men, and that they are returning to a normal situation wherein they will have enough children to replace themselves and to provide for a small increase from generation to generation. Under the impact of the movement for the restriction of families during the last century the ideal family canme to be looked upon as having only two children. This ideal is reflected in the size of the families of the men born before 1870. But the pendulum has swung too far. Now it is moving back. That the backward swing should begin among the most distinguished men is natural, for all new movements begin among the more thoughtful and far-sighted members of society. The original movement in the opposite direction toward the reduction of the unduly large families of a century or more ago also began with the leaders. But what the leaders are doing in the present generation, the rank and file will probably do later.