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PubMed1998

[Bone mineral density in nursing infants and young children (0-4 years old) at the level of the lumbar spine. The normal patterns].

OBJECTIVE: A cross-sectional study of bone mineral density was conducted in a normal population of children with ages ranging from the neonatal period to 4 years with the aim of establishing normal bone mineral density (BMD) patterns. PATIENTS AND METHODS: Bone mineral content density was measured by dual-energy X-ray absorptiometry at the level of the lumbar spine (L2-L4) in 147 normal children (69 boys, 78 girls, age range: 15 days to 4 years) randomly selected from the urban area of Barcelona. RESULTS: Weight, length and height were in the normal age distribution. Bone mineral content values were corrected by the vertebral surface area scanned and expressed as bone mineral density values (grams of hydroxyapatite/cm2). Bone mineral density values increased progressively from birth to 4 years and values were similar in both sexes. A statistically significant correlation was found between BMD values and age (r = 0.82, p < 0.001), weight (r = 0.87, p < 0.001) and length or height (r = 0.79, p < 0.001). Lumbar bone mineral density values increased annually, but the periods of higher increase were observed during the first 2 years of life. Bone mineral density values showed a similar pattern to height growth velocity. CONCLUSIONS: We report normative data for bone mineral density at the lumbar spine in our normally-growing pediatric population from the neonatal period to 4 years. These data provide a tool for the study and follow-up of pediatric populations at risk for low bone mineralization during early childhood.

Absorptiometry, Photon↗
PubMed2001

A review of taurodontism with new data on indigenous southern African populations.

The prevalence and degree of taurodontism (enlargement of the pulp cavity) in the mandibular permanent molars of two recent population samples from southern Africa were investigated quantitatively from lateral radiographs. The degree of occlusal wear was scored and two measures of relative pulp cavity size were recorded for each tooth. There was a significant association between increased attrition and a reduction in the size of the pulp cavity when all of the teeth were considered together, but no correlation among individual molar types within each sample. In both the Zulu (n=68 individuals) and Khoisan (n=28 individuals) samples, third molars had the highest prevalence of taurodontism and first molars the lowest. The data for Zulus are similar to those recorded for other modern populations (e.g. white and black Americans, and Israelis), whereas the Khoisan data exhibit significantly higher frequencies. An increased appreciation of the distribution of this variant in modern human populations would contribute to an understanding of its possible evolutionary significance in the human fossil record.

Africa, Southern↗
PubMed1978

Impact of age integration on the well-being of elderly tenants in public housing.

The social, psychological, and environmental situations of a national area probability sample of 1875 elderly tenants in 153 public housing sites were studied by means of interviews with tenants and project mangers and direct observation of social and environmental characteristics of the housing. In this report the association between the age mix of the housing and the well-being of the tenants was investigated. With a variety of personal, social, and physical environmental characteristics statistically controlled, age segregation showed small but reliable relationships to on-site activity participation, morale, housing satisfaction, and neighborhood motility. The results are discussed in terms of policy and planning designed to maximize options for the individual.

Age Factors↗
PubMed1996

Insulin sensitivity index, acute insulin response, and glucose effectiveness in a population-based sample of 380 young healthy Caucasians. Analysis of the impact of gender, body fat, physical fitness, and life-style factors.

BACKGROUND: Insulin sensitivity and insulin secretion are traits that are both genetically and environmentally determined. AIM: The aim of this study was to describe the distribution of the insulin sensitivity index (Si), the acute insulin response, and glucose effectiveness (Sg) in young healthy Caucasians and to estimate the relative impact of anthropometric and environmental determinants on these variables. METHODS: The material included 380 unrelated Caucasian subjects (18-32 yr) with measurement of Si, Sg and insulin secretion during a combined intravenous glucose (0.3 grams/kg body weight) and tolbutamide (3 mg/kg body weight) tolerance test. RESULTS: The distributions of Si and acute insulin response were skewed to the right, whereas the distribution of Sg was Gaussian distributed. Sg was 15% higher in women compared with men (P < 0.001). Waist circumference, body mass index, maximal aerobic capacity, and women's use of oral contraceptives were the most important determinants of Si. Approximately one-third of the variation of Si could be explained by these factors. Compared with individuals in the upper four-fifths of the distribution of Si, subjects with Si in the lowest fifth had higher waist circumference, higher blood pressure, lower VO2max, and lower glucose tolerance and fasting dyslipidemia and dysfibrinolysis. Only 10% of the variation in acute insulin response could be explained by measured determinants. CONCLUSION: Estimates of body fat, maximal aerobic capacity, and women's use of oral contraceptives explain about one-third of the variation in Si in a population-based sample of young healthy Caucasians.

Adolescent↗
PubMed2002

Soft tissue profile in Anatolian Turkish adults: Part I. Evaluation of horizontal lip position using different soft tissue analyses.

This study investigated cephalometrically the horizontal lip position of Anatolian Turkish adults using the soft tissue analyses of Steiner, Ricketts, Burstone, Sushner, Holdaway, and Merrifield. Ninety-six adults (55 females, mean age, 21.63 years; 41 males, mean age, 22.45 years) with Angle Class I occlusal relationships were selected from the dentistry students at the University of Istanbul and called the dentally normal group. Their lateral cephalometric radiographs were analyzed, and 44 subjects (21 females, mean age, 21.35 years; 23 males, mean age, 21.41 years) with normal anteroposterior (ANB angle, 2 degrees +/- 2 degrees ) and vertical (SN-MP angle, 32 degrees +/- 5 degrees ) skeletal relationships were selected from the dentally normal group and called the dentally and skeletally normal group. Ten linear and 6 angular measurements were analyzed on each radiograph, and the significance of the differences between the groups was studied by means of the Mann-Whitney U test. The results of this study indicate that in Anatolian Turkish adults (1) the upper and lower lips were retrusive according to the norms of Steiner and Ricketts; (2) both the upper and lower lip values were within the normal range according to Burstone's B line; (3) the upper lip was protrusive and the lower lip was retrusive compared with the norms developed by Sushner for a black population; (4) the value for the lower lip was similar to the standard proposed by Holdaway, while the values for the nasal prominence and the H angle were greater than Holdaway's norms; and (5) the Z angle was smaller than the norm established by Merrifield.

Adult↗
PubMed1996

Comparability of treatment groups and risk factors for parasitemia at the first antenatal clinic visit in a study of malaria treatment and prevention in pregnancy in rural Malawi.

The problems of Plasmodium falciparum infection in pregnant women have been described in numerous sub-Saharan African countries, but the frequency of parasitemia at the first antenatal visit and risk factors for infection have not been fully investigated. During a prospective antimalarial treatment and prophylaxis trial in pregnant women in Malawi (three groups receiving a chloroquine regimen and one group receiving a mefloquine regimen), we examined women at their first antenatal clinic visit to evaluate these issues and to verify that subjects in the study treatment/prevention arms were similar. Among 4,127 women with enrollment blood smear results, 1,836 (44.5%) were parasitemic. The highest infection rates and densities were observed in primigravidas (66% infected, geometric mean parasite density [GMPD] = 1,588 parasites/mm3 of whole blood), followed by second pregnancies (46% infected, GMPD = 615 parasites/mm3) and subsequent pregnancies (29% infected, GMPD = 238 parasites/mm3), (P < 10(-6) for both infection prevalence and density, by chi-square test for trend). Significant risk factors for parasitemia at first antenatal clinic visit in a multivariate model included low gravidity, high transmission season, no use of prophylaxis before first antenatal clinic visit, young age (< 20 years), human immunodeficiency virus (HIV) infection, low hematocrit, short stature, and second trimester (compared with third trimester). Women in the different treatment arms of the study were generally similar in many characteristics; statistically significant differences, where present, were small. Targeting malaria control efforts to women in their first or second pregnancy and during the high transmission season will be an important strategy to reach most parasitemic women and minimize resource expenditure. Women infected with HIV had a 55% increased risk of parasitemia at their first antenatal clinic visit and may represent an additional important risk group whose numbers may be increasing and who may benefit from identification and management for malaria.

Adolescent↗
PubMed1999

Asthma-like disease in the children living in the neighborhood of Mt. Sakurajima.

We conducted self-administered questionnaire surveys of school children living in the vicinity of Mt. Sakurajima using ATS-DLD questionnaire. In this paper, we report the results of analysis comparing the proportion of children with asthma-like disease in the area exposed to the volcanic ash and gases released by Mt. Sakurajima and control areas. Asthma-like disease was ascertained using ATS-DLD questionnaire and the definition proposed by the study group established by Environmental Protection Agency in Japan. The proportion of children with asthma-like disease was not different between the exposed and control groups. The odds ratio of asthma-like disease comparing the exposed and control groups was 1.1 and its 95% confidence interval was 0.7-1.8 (P = 0.583). When the exposed area was divided into Tarumizu city. Sakurajima town and Kagoshima city, none of them showed an elevated proportion of children with asthma-like disease when compared with the control area. In the entire study population including both the exposed and control groups, the proportion of children with asthma-like disease was 6 and 3% in boys and girls, respectively. These values were quite similar to those obtained from a survey of 45,674 school children in western districts in Japan in 1992. In conclusion, the present study indicates that the proportion of children with asthma-like disease is not elevated in the exposed area. Further investigations are necessary to confirm our conclusions.

Air Pollutants↗
PubMed1989

Quantitating the effect of cystic fibrosis on linear growth by mathematical modelling of longitudinal growth curves.

Cystic fibrosis (CF) is a systemic disorder that may compromise linear growth in childhood, but quantitating this effect requires accurate mathematical models for normal growth. Anthropometric measurements on a cohort of 37 CF patients were analyzed using the growth model of Preece and Baines (1978) which reduces longitudinal height data to 6 quantitative parameters. When parameter means for CF females (n = 19) were compared to the reference population in the Harpenden growth study, the overall difference was significant (p less than 0.05). Examination of the derived biological parameters revealed 12-month and 14-month delays in age at take off and peak height velocity, respectively, indicating that the pubertal growth spurt in female patients is delayed. Mean ages at take off and peak height velocity were delayed 9 months in the CF males (n = 18). These results reaffirm the observation that CF females experience greater morbidity in later childhood and adolescence than males, and illustrate a quantitative approach that should facilitate further examination of CF and the efficacy of different treatment modalities on the disease process in both sexes.

Adolescent↗
PubMed1998

Prevalence of orthodontic asymmetries.

Epidemiological studies of the occlusal status of the US population do not include the prevalence of orthodontic asymmetries. To estimate the magnitude of dental and facial asymmetries in adolescents with no history of orthodontic treatment, data were analyzed from two mass orthodontic screenings that had been conducted on public schoolchildren in Florida. An analysis of orthodontic records of patients in treatment at the Virginia Commonwealth University graduate orthodontic clinic provided prevalence data on dental and facial asymmetries in a population of orthodontic patients. In the Florida studies, the two screenings yielded 5,817 untreated children (mean age, 9.3 +/- 0.8 years) and 861 untreated children (mean age, 14.4 +/- 0.5 years). Sagittal molar asymmetry was found in 30% of the children in the first screening and in 23% in the second screening. Additional asymmetry assessments in the second screening showed 12% facial asymmetry and 21% noncoincidence of dental midlines. Among orthodontic patients, the most common asymmetry trait was mandibular midline deviation from the facial midline. This occurred in 62% of patients, followed, in descending order of frequency, by lack of dental midline coincidence (46%), maxillary midline deviation from the facial midline (39%), molar classification asymmetry (22%), maxillary occlusal asymmetry (20%), mandibular occlusal asymmetry (18%), facial asymmetry (6%), chin deviation (4%), and nose deviation (3%).

Adolescent↗
PubMed1995

Dental findings in geriatric populations with diverse medical backgrounds.

OBJECTIVE: To determine whether there is a difference in the oral/dental health in older persons with different life styles and medical status. STUDY DESIGN: Survey (cross-sectional study) included four groups: (1) subjects (n = 123) living in a residential retirement home or community dwelling; (2) subjects (n = 218) seeking dental treatment at a Veterans Affairs Dental Outpatient Clinic; (3) subjects (n = 132) resident in a VA long-term care facility; and (4) subjects (n = 81) recently admitted to a VA acute care ward with a diagnosis of cerebral vascular accident or other neurologic problem. Each subject answered questions on medical and dental health and dietary preferences in a comprehensive interview. They were given a comprehensive dental examination that included measurements of stimulated salivary flow and minor salivary gland output. RESULTS: The data from groups 2 and 3 confirmed previous reports that independent living subjects have better oral/dental health than dependent living subjects. The data from groups 1 and 4, obtained from geriatric populations on the opposite ends of the medical health/disease continuum provide new information that suggests that good medical health and good oral/dental health are linked. The subjects in group 1 were very healthy as judged by their longevity; 54% were > or = 80 years and they had low reported prevalence of medical disease. Only 6% were edentulous and the dentate persons were missing 4.5 teeth. In contrast, over 50% of the patients in group 4 were < 70 years; they had an edentulous rate of 49% and among the dentate persons had an average 12 missing and 5 decayed teeth. CONCLUSIONS: The medically healthy persons had excellent dental health whereas the sickest persons were either edentulous or had many missing teeth.

Acute Disease↗
PubMed1994

A population-based autopsy study of sudden, unexpected deaths from natural causes among persons 5 to 39 years old during a 12-year period.

All unexpected deaths in New Mexico from 1977 to 1988 were reviewed. By statute each such death must be reported to the Office of the Medical Examiner (OMI) and according to institutional policy autopsied even when death is presumed to be from natural causes. From this group the 650 index cases that form the basis of this report were obtained. The crude rate of sudden, unexpected death among New Mexico residents 5 to 39 years old during the study period was 6.6/100,000 persons at risk. As documented by autopsy, the underlying cause of death in a majority of these cases (53.4%) was related to cardiovascular disease and alcoholism. Male persons in general are at increased risk for sudden, unexpected death, and American Indian and black male persons are at greater risk than their Anglo and Hispanic counterparts. American Indians account for a disproportionate share of the unexpected deaths resulting from alcoholism, and black male persons are at particular risk for unexpected death resulting from cardiovascular diseases. This report emphasizes the importance of life style and diet in the well-being of persons 5 to 39 years old.

Adolescent↗
PubMed1995

Genetic and phenotypic (co)variances for production traits of intact male populations of purebred and composite beef cattle.

Least squares means, genetic (sigma g) and phenotypic (sigma p) standard deviations, and phenotypic coefficients of variation (CV) were estimated for growth traits of intact males from 12 breed groups combined, for nine purebreds combined, and for the F1, F2, F3, and F4 generations of three composite populations to which the nine purebreds contributed. Heritabilities (h2) and genetic (rg) and phenotypic (rp) correlations were estimated for growth traits, calving difficulty of calves with dams of different ages, and gestation length. Coefficients of variation and sigma g generally were similar for composites and contributing purebreds. Generally, estimates of h2 were similar for all breed groups combined, contributing purebreds combined, and composites combined. Estimates of h2 for calving difficulty were higher for calves with 2-yr-old dams than for calves with dams > or = 3 yr old and were sufficiently high (.27 and .31) to be a useful selection criterion for reducing calving difficulty. Mean h2 pooled within all breed groups ranged from .35 for 200-d weight and 368-d weight to .48 for 368-d height. Estimates of h2 for subjective scores of anatomical traits were only slightly lower than those for growth and size traits. The h2 of scrotal circumference (.43) was similar to those for growth and size traits. Genetic correlations between birth weight and calving difficulty were similar for 1) calves with dams of all ages, 2) calves with 2-yr-old dams, and 3) calves with dams > or = 3 yr old.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1997

Geographic variation in expenditures for workers' compensation physician claims.

We examine interstate variations in the cost of claims for physician care using injury claims from Worker's Compensation, and consider some of the factors that may explain cost differences. Multivariate regression analysis is used to isolate state variations, while controlling for personal and injury characteristics, and state characteristics. Statistical analyses reveal considerable variation in expenditures for physician care of injuries across states, even after controlling for case mix and state characteristics. We also find that the presence of HMOs and of general practitioners as a percent of physicians are associated with lower claims, and that the percent of the state that is urban is associated with higher claims. The large variation in costs suggests a potential to affect the costs of physician care for work-related injuries.

Geography↗
PubMedDate not supplied

Well-being changes in response to 30 years of regional integration in Maya populations from Yucatan, Mexico.

Infant mortality rate (IMR), overall frequency of linear enamel hypoplasia (LEH), sexual dimorphism in LEH, age of onset of LEH, and age at menarche were used as indicators to test the hypothesis that the origin and development of the tourist industry and increased state participation on Maya subsistence agriculturists in the early 1970s had improved the well-being of the Maya. Two historical moments where inferred from the data. The first was derived from cheap and effective immunization and sanitation campaigns that reduced IMR from 143.4/1,000 live births in the early 1960s to 97.4 in the early 1970s. State participation broke the undernutrition-disease cycle enough to reduce LEH frequencies significantly (from 71.9% in individuals born before 1971 to 51.5% in those born in 1971 or after, chi(2) = 55.72; 1 df; alpha = 0.00001) and to eliminate the sex difference in LEH expression (from a 14.8% LEH difference between men and women before 1971 [Male/Female Odds Radio = 0.45, alpha significant at 0.05] to a nonsignificant 2% difference). Improvement in overall living conditions reflected in a "modern stage" infant mortality regime and an almost disappearance of LEHs, resulted from gradual improvements in living conditions that did not become apparent until the 1980s. Trends in the age at menarche are not statistically significant, probably due to methodological limitations. However, if overall living conditions continue to improve or stay as they are today, accelerations in maturation should become noticeable.

Adolescent↗
PubMed1997

Heritability of 39 orthodontic cephalometric parameters on MZ, DZ twins and MN-paired singletons.

The twin method is one of the most effective methods available for investigating genetically determined variables in orthodontics, as well as in other medical fields, depending on the variance in the shape and the size of skull and teeth, both on genetic and environmental influences. The former have been extensively evaluated and, in particular, most of the facial and dental cephalometric parameters have shown high heritability, the vertical parameters have a higher genetic control compared with the horizontal ones. Nevertheless, most of the results provided by twin research have been considered arbitrary if directly transferred to a singleton population and in further studies, including extensive analysis of the parents, familial and nutritional habits have been recommended. In this study, heritability of 39 lateral orthodontic cephalometric parameters has been estimated by both statistical method of path analysis and Dahlberg' quotient in three orthodontic samples of young monozygotic and dizygotic twins and same-sex pairs of singletons living together, matched for sex and age, to evaluate genetic versus environmental factors affecting heritability of craniofacial features in the aim to obtain results not only statistically significant but also transferrable to a singleton population. Different inheritance trends, showing the highest concordance of values between monozygotic twin pairs when compared with dizygotic twin pairs or the same-sex singletons paired group, come from the 39 selected lateral cephalometric parameters, confirming the hypothesis that strong genetic control is exerted especially on the vertical ones. Heritability seems to have more influence on anterior vertical parameters than posterior. Mandibular structure seems to be more genetically determined than mandibular size. All five Ricketts' cephalometric typological parameters confirm high heritability coefficients, the same applies to the linear horizontal McNamara's measurement and lower incisor to A-Pg line. The two tested statistical methods showed relevant concordance of results.

Adolescent↗
PubMed2000

Hematological parameters in high altitude residents living at 4,355, 4,660, and 5,500 meters above sea level.

There have been a number of reports describing the hematological indicators of Andean residents living at altitudes above 4,000 m, but several confounding factors have made the published results difficult to interpret. To clear up the effect of hypoxia on hemoglobin concentration (Hb, g/dL), hematocrit (Hct, %) and red blood cell concentration (RBC, cells/microL), this publication describes and analyzes these variables in children, men, and women from three large and homogeneous populations living at 4,355 m (n = 151), 4,660 m (n = 400), and 5,500 m (n = 273) in the Southern Peruvian Andes. Hb, Hct, and RBC increase with age in men (p < 0.001), as well as in women (p < 0.001) at the three altitudes of the study. In children (boys and girls) living at 5,500, Hb increases 11% when compared with children living at 4,355 m, and in adults, Hb increases 9.6% when comparing the same altitudes. The maximum percentage increase in Hb with age was 5.6% at 5,500 m, in men and 3.2% at 4,355 m, in women. The average percentage of difference for the Hb concentration between adult men and women is 6.6% at 4,355 m, 9.8% at 4,660 m, and 11.6% at 5,500 m. The differences in Hb concentration between men and women can only be seen after puberty. Finally, Hb is higher in older than younger women, which confirms the role of menopause in the development of erythremia. The result of this analysis reinforces the notion that Hb and Hct seem to be stable and useful parameters for acclimatization only at moderate altitudes; with aging or with increasing altitude, they may become excessive and lose their efficiency to protect the venous oxygen pressure.

Acclimatization↗
PubMed1976

Born to be poor: birthplace and number of brothers and sisters as factors in adult poverty.

Household heads who grew up as members of large families and/or as natives of small towns or rural areas tend to have less education and are more likely to be poor than those coming from small families and/or large cities. Data to support these conclusions have been drawn from two independent sources--a special Social Security Administration supplement to the April 1968 Current Population Survey and findings from the Retirement History Study conducted by the Social Security Administration.

Educational Status↗