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Secular change in sitting height and lower limb height of children, youths, and young adults of Afro-black, European, and Japanese ancestry.

During a large part of the last 100 years many human populations in Asia, Australia, Europe, and North America have increased in standing height. The amount of increase has risen with age from infancy to mid-adolescence, and diminished with age from mid-adolescence to early adulthood. In the present paper standing height is broken into two components and-for American black, American white, and Japanese groups-each component is found to (1) show substantial secular increase, and (2) yield a trend of quantitative difference similar to that of standing height. Average sitting height of Japanese males increased during the 33 years between 1937 and 1970 by 2.5 cm at age 8 years, 4.1 cm at age 14 years, and 2.9 cm at age 16 years; corresponding values for lower limb height were 3.7 cm, 5.3 cm, and 3.9 cm. During the 80 years following 1881, American white females ages 9 years and 13 years living in the Midwest increased in average sitting height by 4.6 cm and 5.4 cm, and in average lower limb height by 4.9 cm and 5.2 cm. For both dimensions of each racial group, secular change is greater at mid-adolescence than in early adulthood.

Adolescent

Aging and secular change in adult stature in rural Colombia.

Age-associated changes in adult stature of a cross-sectional sample of 634 adults from rural Colombia were estimated by multiple regression of stature and age controlling for subischial length, and from equations predicting maximum attained stature from subischial length. From these analyses the estimated rate of loss in stature due to aging per se for men was 0.12 cm/yr, while for women it was 0.03 cm/yr. When corrected for aging, several secular trends in adult stature were evident, although none were statistically significant.

Adult

Some secular changes in the growth of American-born and native Japanese children.

Three hundred and sixteen (35%) of the American-born Japanese children whose height, weight, and skeletal age were recorded in 1956-57 were reexamined as young adults between 1968 and 1974, when they were found to be taller, heavier and shorter legged than men and women in Japan who were born in the same years as they. These differences between the American-born and the native Japanese adults were relatively smaller than they had been during childhood, due to both an acceleration in the growth rate of the native Japanese and a concomitant decline in that of the American-born Japanese during the intervening years. A comparison of our 1956-57 data with Kondo and Eto's findings in Los Angeles in 1971 shows that there has been very little increase in the size of California-Japanese children since 1956. The curves of average heights of native Japanese children 6 to 20 years of age, at 10-year intervals from 1900 to 1970, disclosed the changing rate at which they grew during different decates of that period. Those curves and other data discussed in this paper provide additional evidence of the biological superiority of the human female as compared with the male.

Adolescent

The secular changes of skin and venereal diseases in Nigeria.

A retrospective review of the changing phase of the incidence of dermatological and venereal diseases, as seen in University Teaching Hospital practice in Lagos, Nigeria is presented. About 8,849 new patients were seen over a 5-year-period. An analysis of the dermatological conditions encountered is made, while brief reports of few common skin conditions are also given. The clinical pattern was similar to those of Western countries, but with addition of a great number of dermatoses. This similarity has been modified by epidemiological factors. A national program for improvement of the environmental health including control of industrial and communicable diseases will ameliorate the increasing morbidity of tropical dermatology.

Female

Colon cancer and diet, with special reference to intakes of fat and fiber.

Colon cancer, rare in the past, and in developing populations, currently accounts for 2 to 4% of all deaths in Western populations. Evidence suggests the primary cause to be changes in diet, which affect the bowel milieu intérieur. It is possible that in sophisticated populations, the higher concentrations of fecal bile acids and sterols, and longer transit time, favor the production of potentially carcinogenic metabolites. Of secular changes in diet, evidence suggests that the following may have etiological importance: 1) the fall in intake of fiber-containing foods with its effects on bowel physiology, and 2) the decreased fiber but increased fat intakes, in their respective capacities to raise concentrations of fecal bile acids, sterols, and other noxious substances. For possible prophylaxis against colon cancer, recommendations for a lower fat intake, or a higher intake of fiber-containing foods (apart from fiber ingestion from bran) are extremely unlikely to be adopted. For future research, western populations with considerably lower than average mortality rates, e.g., Seventh Day Adventists, Mormons, the rural Finnish population, as well as developing populations, demand intensive study. Also requiring elucidation are the respective roles of diet and of genetic constitution on concentrations of fecal bile acids, etc., and on transit time, in prone and nonprone populations.

Adult

Integrating genomic and spatial analyses to describe tuberculosis transmission: a scoping review.

Tuberculosis remains a leading cause of infection-related mortality, and efforts to reduce its incidence have been hindered by an incomplete understanding of local Mycobacterium tuberculosis transmission dynamics. Advances in pathogen sequencing and spatial analysis have created new opportunities to map M tuberculosis transmission patterns more precisely. In this scoping review, we searched for studies combining pathogen genetics and location data to analyse the spatial patterns of M tuberculosis transmission and identified 142 studies published between 1994 and 2024. Secular changes in genetic methods were observed, with genome sequencing approaches largely replacing lower-resolution genotyping methods since 2020. The included studies addressed four primary research questions: how are tuberculosis cases and M tuberculosis transmission clusters geographically distributed; do spatially concentrated M tuberculosis clusters exist, and where are these areas located; when spatial concentration occurs, what host, pathogen, or environmental factors contribute to these patterns; and do identifiable relationships exist between the spatial proximity of tuberculosis cases and the genetic similarity of the M tuberculosis isolates infecting these individuals? Collectively, in this Review, we examined the available study data, evaluated the analytical requirements for addressing these questions, and discussed opportunities and challenges for future research. We found that the integration of spatial and genomic data can inform a detailed understanding of local M tuberculosis transmission patterns, but improved study designs and new analytical methods to address gaps in sampling completeness and to integrate additional movement data are needed to fully realise the potential of these tools.

Humans

Papanicolaou testing and hysterectomy prevalence in low-income communities: a survey in Los Angeles County.

A survey of the prevalence of Papanicolaou (Pap) testing and of hysterectomy and a feasibility study were conducted in low-income communities with high rates of cervical cancer, identified by an analysis of mortality and case rates. Although about 90% of the women reported having had a Pap regular testing. For example, in the 5 years preceding the study (1971--75), about a quarter of the women had been tested only once and about a third not at all. No evidence of a secular change in hysterectomy prevalence in these communities was found.

Adult

[Sugar consumption and prenatal acceleration. I. Studies in the history of medicine on the coincidence and connection of these 2 secular phenomenon].

A comparative historic evaluation reveals an astonishing world-wide relationship between prenatal acceleration, i.e. secular changes of birth-weight and percentage of "large babies", of distinct population groups, and their sugar consumption. They seem to be "connected" as they are regularly "conjoined" (HUME [46]). A statistically highly significant correlation between these two phenomena was established for Switzerland and Germany. The assumption of a causal relationship was confirmed by the abrupt development of growth acceleration together with the rapid increase in the per capita sugar consumption observed in an experiment-like situation in certain Canadian Eskimo populations in recent years.

Birth Weight

Secular trends in human growth, maturation, and development.

Rates of growth during childhood have increased considerably during the past 50-100 years. Because they are associated with increased rates of maturation, these size increases are maximal at ages when recently measured groups are pubescent but those measured in the past had not reached pubescence. Large secular increases in rates of growth and maturation have occurred in all developed countries but not in many other countries. There have been secular increases in recumbent length at birth in Italy and France but little change in the United States. The secular increase in childhood stature is much more obvious, being about 1.5 cm/decade for 12-year-old children, although for young adults the secular increase in stature has been about 0.4 cm/decade in most developed countries. In the United States these trends have been similar for blacks and whites during childhood but greater for black men than white men. Similarly, secular trends in birth weights have been small, but there have been large trends for children (about 1.5 kg/decade for 12-year-olds). These secular changes in size have been associated with an acceleration of maturation that is most evident in the 0.3 years/decade advancement in age at menarche. This advancement has now ceased in Norway and England. The changes in body proportions during recent decades are less marked than those in body size. Leg length, particularly the length of the thigh, seems to have increased more than stature in men but not women; chest circumference has increased more rapidly than stature in each sex. The relationships between stature and weight have changed in different ways in various national groups. Similarly, the relative changes in head length and head breadth vary with the groups studied. Few sets of data allow conclusions about possible secular trends in body composition, but subcutaneous fat thicknesses have increased, especially at the upper percentiles. Also strength, which reflects muscle mass, has increased absolutely, although it has decreased relative to stature. Undoubtedly the secular trend is due to various factors; the identification of causes is necessarily speculative. Changes in nutrition alone could not account for the trends which exceed the original socioeconomic differentials. In the United States, there have been per capita increases in the intake of protein and fat from animal sources, decreases in carbohydrates and fat from vegetable sources, and little change in caloric intake. It is not clear that these changes constitute better nutrition. The secular trends could reflect environmental improvements, specifically changes in health practices and living conditions leading to improvements in mortality rates and life expectancy. These factors are interrelated with those concerning family size. Also genetic factors, especially heterosis, may have played a small role in causing the secular trends...

Body Composition

Pretherapeutic morbidity in the prognostic staging of acute leukemia.

To classify the clinical severity of acute leukemia, we have used the degrees of pretherapeutic infection and hemorrhage to construct a taxonomy containing three "stages". The stages are associated with survival gradients that are clinically and statistically distinctive in both acute lymphoblastic leukemia and acute nonlymphoblastic leukemia. Median survival ranged from 64.0 months for stage 1 to 10.5 months for stage 3 in acute lymphoblastic leukemia, and from 7.1 months for stage 1 to 1.2 months for stage 3 in acute nonlymphoblastic leukemia. The gradients, which persist when other prognostic factors and secular therapeutic changes are taken into account, are more distinctive than those found with other forms of stratification.

Acute Disease