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1.
Background: The human body has undergone significant changes in stature and other areas, which reflect secular trends associated with socioeconomics.

Aim: To analyse cranial morphological traits for deciphering if they are subject to secular trends.

Subjects and methods: Two documented skeletal collections were sampled for a total of 525 individuals from 1849–1960. Cranial morphological traits were scored and input into time series statistics (logistic regression).

Results: In females, nuchal crests have enlarged, while glabella has decreased. In males, supraorbital margins have dulled, while glabella decreased. Sexual dimorphism increased in supraorbital margins.

Conclusion: The patterns in the data here reflect those found in other areas of the skeleton, namely height, as regards to secular trends. These findings can be extended to stature and cranial changes that parallel socioeconomic trends during the Industrial Revolution, antebellum period and after.  相似文献   


2.
Background: Proteinuria is an uncommon clinical manifestation of IgA nephropathy and is usually seen in cases with severe lesions like endocapillary proliferation. However, it is occasionally seen even with cases with mild glomerular manifestations and may even be of nephrotic range.

Predictor: Podocyte foot process effacement.

Outcome: Severity of proteinuria.

Measurements: Podocyte foot process effacement was measured. Morphometric analysis was performed on transmission electron microscope images using a computerized digital photomicrograph system (BioWizard 4.2 Image analysis software, New Delhi, India). Proteinuria was measured quantitatively assigned into five grades.

Results: It was found that as the extent of proteinuria increased, the effacement ratio also increased, and this was most significant between “no” proteinuria and the rest of the categories.

Conclusion: Nephrotic presentation in IgA nephropathy is a known phenomenon and in certain cases may show near normal glomerular morphology with severe foot process effacement on EM being the only significant finding to explain the proteinuria. Proteinuria in these cases shows a significant correlation with degree of foot process effacement. Renal biopsy is important in these cases because they are known to have a better prognosis and are usually steroid responsive.  相似文献   


3.
Objective: The aim of this study was to establish normative values for torso muscle endurance in adolescents aged 15–18 years. It was hypothesized that torso endurance profiles of adolescents differs between males and females and between adolescents and adults.

Background: Decreased torso muscle endurance has been identified as a potential personal risk factor for low back pain development in both adolescents and later years together with being detrimental for athletic performance.

Design: Measurement of torso muscle endurance, established through four tests performed in random order in a healthy adolescent population.

Setting: High school in Novi Sad, Province of Vojvodina, Republic of Serbia.

Methods: Two hundred and ninety-four adolescents from one high school (178 males and 116 females) were grouped into four age strata. Selected isometric torso muscle endurance tests were: Biering-Sørensen test for extensor endurance; Flexor endurance test; right and left Side Bridge tests. The mean, ratio, standard deviation and 25th, 50th and 75th percentile scores were determined for each gender/age strata.

Results and conclusion: Males had higher lateral torso endurance than females. Adolescents in general demonstrate their peak lifetime endurance as they appear more endurable than children and comparable adult groups. These data of endurance times, their ratios and percentiles in healthy normal subjects form a database bridging existing data for children and adults that may be useful for guiding training and rehabilitation.  相似文献   


4.
Background: Cross-sectional study among immigrant and native children from Emilia-Romagna (Italy).

Aim: The purpose of the present study was to examine the relative contribution of weight status, ethnicity and sex on body dissatisfaction in a sample of children from Emilia-Romagna (Italy).

Subjects and methods: Primary school children (226 immigrants and 1206 Italians) aged 6–11 years were measured: immigrant children were divided into Asians, Africans, Latin Americans and East Europeans. Height and weight were measured and Body Mass Index (BMI) was calculated. Body image perception was assessed using Body Silhouette Charts. A body dissatisfaction score (BDS) was derived by subtracting the "ideal self" from the "self" score.

Results: Weight status disorders were higher in immigrants than in native-born males; Italian females had higher prevalence of underweight and overweight and lower prevalence of obesity than immigrants peers. BDS rose with the increase of weight status categories.

Conclusions: Awareness of body image size and increasing body dissatisfaction with higher weight status is established in childhood, regardless of ethnicity and gender.  相似文献   


5.
Context: Epigenetics represents a still unexplored research field in the understanding of micro- and macro-evolutionary mechanisms, as epigenetic changes create phenotypic diversity within both individuals and populations.

Objective: The purpose of this review is to dissect the landscape of studies focused on DNA methylation, one of the most described epigenetic mechanisms, emphasizing the aspects that could be relevant in human adaptations.

Methods: Theories and results here considered were collected from the most recent papers published.

Results: The matter of DNA methylation inheritance is here described as well as the recent evolutionary theories regarding the role of DNA methylation—and epigenetics in a broader sense—in human evolution. The complex relation between (1) DNA methylation and genetic variability and (2) DNA methylation and the environmental stimuli crucial in shaping genetic and phenotypic variability through the human lineage—such as diet, climate and pathogens exposure—are described. Papers about population epigenetics are also illustrated due to their high relevance in this context.

Conclusion: Genetic, epigenetic and phenotypic variations of the species, together with cultural ones, are considerably shaped by a vast range of environmental stimuli, thus representing the foundation of all human bio-cultural adaptations.  相似文献   


6.
7.
Background: Parturition lines have been described in the teeth of a number of animals, including primates, but never in modern humans. These accentuated lines in dentine are comprised of characteristic dark and light component zones.

Aim: The aim of this study was to review the physiology underlying these lines and to ask if parturition lines exist in the third molar tooth roots of mothers known to have had one or more children during their teenage years.

Methods: Brief retrospective oral medical obstetric histories were taken from four mothers and compared with histological estimates for the timing of accentuated markings visible in longitudinal ground sections of their wisdom teeth.

Results: Evidence of accentuated markings in M3 root dentine matched the age of the mother at the time their first child was born reasonably well. However, the dates calculated for inter-birth intervals did not match well.

Conclusions: Parturition lines corresponding to childbirth during the teenage years can exist in human M3 roots, but may not always do so. Without a written medical history it would not be possible to say with confidence that an accentuated line in M3 root dentine was caused by stress, illness or was a parturition line.  相似文献   


8.
9.
Background: Studies of the process of human mate selection and attractiveness have assumed that selection favours morphological features that correlate with (genetic) quality. Degree of masculinity/femininity and fluctuating asymmetry (FA) may signal (genetic) quality, but what information they harboured and how they relate to fitness is still debated.

Aim: To study strength of associations between facial masculinity/femininity, facial FA, attractiveness and physical strength in humans.

Subjects and methods: Two-hundred young males and females were studied by measuring facial asymmetry and masculinity on the basis of frontal photographs. Attractiveness was determined on the basis of scores given by an anonymous panel, and physical strength using hand grip strength.

Results: Patterns differed markedly between males and females and analysis method used (univariate vs multivariate). Overall, no associations between FA and attractiveness, masculinity and physical strength were found. In females, but not males, masculinity and attractiveness correlated negatively and masculinity and physical strength correlated positively.

Conclusion: Further research into the differences between males and females in associations between facial morphology, attractiveness and physical strength is clearly needed. The use of a multivariate approach can increase our understanding of which regions of the face harbour specific information of hormone levels and perhaps behavioural traits.  相似文献   


10.
Background: Genes encoding KIR receptors are clustered in one of the most variable regions of the human genome. KIR gene frequencies vary in worldwide populations and reveal high probability of individuals differing in their gene content.

Aim: This study aimed to investigate KIR diversity among the northern Indian population who share features with either Western Eurasian or East Asian populations. It sought to decipher how northern Indians are associated phylogenetically with global populations whilst also focusing on differentiation of populations.

Subjects and methods: This paper studied 867 northern Indians using PCR-SSP. Gene and genotypic frequencies were calculated, using statistical analyses. Findings were compared against 76 global populations of differing ethnicities.

Results: This northern Indian population shared characteristics with Western Eurasian or Asian Indian populations, as is evident from genetic distance, clustered heatmap, phylogenetic assessment and principal component analysis. The findings are consistent with the demographic history of northern India, including specific features, such as presence of comparatively high KIR B-haplotype as compared to A-haplotype.

Conclusion: KIR frequencies and profiles of northern Indians were more similar to Western Eurasians, Africans and Asian Indians. This may suggest that KIR genes are under constant evolutionary pressures and selection, which may be linked to different invading pathogens.  相似文献   


11.
Background: Different structural and non-structural models have been used to describe human growth patterns. However, few studies have compared the fitness of these models in an African transitioning population.

Aim: To find model(s) that best describe the growth pattern from birth to early childhood using mixed effect modelling.

Subjects and methods: The study compared the fitness of four structural (Berkey-Reed, Count, Jenss-Bayley and the adapted Jenss-Bayley) and two non-structural (2nd and 3rd order Polynomial) models. The models were fitted to physical growth data from an urban African setting from birth to 10 years using a multi-level modelling technique. The goodness-of-fit of the models was examined using median and maximum absolute residuals, Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC).

Results: There were variations in how the different models fitted to the data at different measurement occasions. The Jenss-Bayley and the polynomial models did not fit well to growth measurements in the early years, with very high or very low percentage of positive residuals. The Berkey-Reed model fitted consistently well over the study period.

Conclusion: The Berkey-Reed model, previously used and fitted well to infancy growth data, has been shown to also fit well beyond infancy into childhood.  相似文献   


12.
Background: The immune factors in human milk protect infants from infection and promote immune development. Evidence suggests that the production of milk-specific immunoproteins is energetically costly, making them a form of maternal investment in offspring health that is subject to life history trade-offs.

Aim: This research tests the relationship between measures of reproductive effort and the production of milk immunoglobulin A (IgA) among Ariaal women, a settled northern Kenyan pastoralist population that experiences nutritional and disease stress.

Subjects and methods: Two hundred and forty-three lactating Ariaal women participated in a questionnaire, anthropometric measurement and milk collection. Milk IgA was analysed using ELISA.

Results: There was a significant U-shaped relationship between post-partum months and milk IgA, reflecting decreasing investment in the current offspring over the early post-partum period and subsequent recovery of maternal energy status near the end. There was also a significant inverse U-shaped relationship between milk IgA and parity, with high parity women showing a drop in milk IgA. In contrast, anthropometric measures of energy status were not associated with the production of milk IgA.

Conclusion: This research shows that patterns of reproductive investment can be demonstrated in milk IgA in the absence of measured energy changes.  相似文献   


13.
Background: Copy Number Variants (CNVs) contribute to a large fraction of genetic diversity and some of them have been reported to offer an evolutionary advantage.

Aim: To identify CNVs in pigmentary loci that could contribute to human skin pigmentation diversity.

Subjects and methods: This study assessed the existence of CNVs in every exon of candidate genes: TYR, TYRP1, DCT, MC1R and SLC24A5, using the Multiplex Amplifiable Probe Hybridization technique (MAPH). This study analysed a total of 99 DNA samples of unrelated individuals from different populations. Validation and further analysis in a larger Spanish sample were performed by RT-qPCR.

Results: Five CNVs were identified by MAPH: DCT exons 4 and 8, TYR exon 1 and SLC24A5 exons 1 and 4. Real-time quantitative PCR (RT-qPCR) confirmed the CNV in exon 1 of SLC24A5. This study further analysed the 5′ promoter region of SLC24A5 and found another CNV in this region. However, no association was found between the CNV and the degree of pigmentation.

Conclusion: Although the functional role of these structural variants in pigmentation should be the subject of future work, the results emphasize the need to consider all classes of variation (both SNPs and CNVs) when exploring the genetics of skin pigmentation.  相似文献   


14.
Background: Attempts to explain the increased risk for metabolic disorders observed in South Asians have focused on the “South Asian” phenotype at birth and subsequent post-natal growth, with little research on pre-natal growth.

Aim: To identify whether divergent growth patterns exist for foetal weight, head (HC) and abdominal circumferences (AC) in a sample of Pakistani and White British foetuses.

Subjects and methods: Models were based on 5553 (weight), 5154 (HC) and 5099 (AC) foetuses from the Born in Bradford birth cohort. Fractional polynomials and mixed effects models were employed to determine growth patterns from ~15 weeks of gestation-birth.

Results: Pakistani foetuses were significantly smaller and lighter as early as 20 weeks. However, there was no ethnic difference in the growth patterns of weight and HC. For AC, Pakistani foetuses displayed a trend for reduced growth in the final trimester.

Conclusion: As the pattern of weight and HC growth was not significantly different during the period under investigation, the mechanism culminating in the reduced Pakistani size at birth may act earlier in gestation. Reduced AC growth in Pakistanis may represent reduced growth of the visceral organs, with consequences for post-natal liver metabolism and renal function.  相似文献   


15.
Background: Adolescence represents a transitional period which is marked by physical, social and psychological changes. Changes in body shape and physical activity especially alter and shape the psychological well-being of adolescents.

Aim: The purpose of this study was to determine the role of physical activity level, body mass index and maturity status in body-related perception and self-esteem of 11–18 years old adolescents.

Subjects and methods: A total of 1012 adolescents participated in this study. The “Social Physique Anxiety Scale”, “Body Image Satisfaction Scale”, “Physical Self-Perception Profile for Children” and “Rosenberg Self-Esteem Inventory” were administered. Physical activity level and body mass index were assessed using the “Physical Activity Questionnaire” and “Bioelectrical Impedance Analyzer”, respectively.

Results: Regression analysis indicated that body mass index was the only predictor of perceived body attractiveness, social physique anxiety, body image satisfaction and self-esteem for female adolescents. For male adolescents, both physical activity and body mass index were correlated with perceived body attractiveness and social physique anxiety. Pubertal status were not correlated with self-esteem and body-related perceptions for both males and females adolescents.

Conclusion: In summary, body mass index and physical activity plays an important role in body-related perceptions and self-esteem of adolescents.  相似文献   


16.
Objectives: This article seeks to identify neuroanatomical differences in ADHD through an overview of systematic reviews that report encephalic differences compared to a control group in volume, area, activation likelihood or chemical composition.

Methods: We conducted a systematic search using Cochrane guidelines and PRISMA criteria in PubMed, Scopus, Web of Science, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects.

Results: Results revealed broad encephalic involvement that includes a functional frontal and cingulate hypoactivation and structural differences in corpus callosum, cerebellum and basal nuclei.

Conclusions: ADHD symptoms might be due to a multi-network unbalanced functioning hypothesis.  相似文献   


17.
Background: The geographical location of Egypt at the crossroads of several major cultural areas between North Africa and the Middle East has contributed to its population history.

Aim: To analyse the genetic structure of the population living in two geographical parts of Egypt.

Subjects and methods: A sample of 112 Egyptians from the North African part of Egypt (Ismailia sample) and a sample of 52 Egyptians from the Asian part Sinai, have been analysed using 10 Alu insertion polymorphisms.

Results: The results of the present study showed a significant genetic difference between the Sinai and Ismailia samples. The latter showed an evident genetic affinity with North African populations; whereas the Sinai sample was found to be genetically closer to the Middle East populations. The Sinai sample showed a low average heterozygosity, unlike that found in the Ismailia sample.

Conclusion: This study provides new insights into the genetic structure of the Egyptian population living in a land bridge between Africa and Asia. Results suggest a genetic discontinuity between the Sinai population and that of the North African part of Egypt. This discontinuity would have been maintained thanks to geo-climatic and social factors.  相似文献   


18.
Context: Serum IgA suppresses immune responses when exposed to antigens recognized by the antibody; however, the underlying mechanism remains unclear.

Objective: We herein clarified the relationships between changes in antigen distribution and antigen-dependent B cell activation in the presence or absence of IgA against the antigen in mice.

Materials and methods: DBA/1J and HR-1 mice were intravenously injected with ovalbumin (OVA) and anti-OVA monoclonal IgA OA-4. The distribution of the antigen and B cell responses were measured.

Results: B cell activation by injected OVA, namely, increases in anti-OVA IgG production and the populations of B220+GL7+ and B220+CD69high splenocytes, was diminished by the co-injection of OA-4. Co-injected OA-4 increased OVA in the serum as well as in the bile and gut. This was coincident with its decrease in the urine due to the inhibition of OVA monomer secretion through the formation of immune complexes. The apparent similarities in the association between fluorescein isothiocyanate (FITC)-OVA and splenic B cells in the presence and absence of OA-4 in vivo appeared to be attributed to compensation between the two effects of OA-4; an increase in serum OVA in vivo and inhibition of the association between OVA and B cells, as suggested by in vitro experiments.

Discussion: Based on these results, the stimulation of B cells by OVA may be directly reduced, at least partly, by the neutralization of OVA by OA-4.

Conclusion: IgA may be an effective drug for the treatment of immune disorders due to its ability to blunt antigen-specific B cell activation.  相似文献   


19.
Context: Expression of various inflammatory mediators in corneal fibroblasts contributes to corneal inflammation.

Objective: The purpose of this study was to assess the possible effects of caffeic acid phenethyl ester (CAPE) on the expression of inflammatory mediators during an inflammatory response in human corneal fibroblasts.

Materials and methods: The levels of interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, and intercellular adhesion molecule-1 (ICAM-1) from IL-1β-exposed human corneal fibroblasts were measured with enzyme-linked immunosorbent assays (ELISA). The regulatory mechanisms of CAPE on cellular signaling pathways were examined using Western blot and electrophoretic mobility shift assays. A functional validation was carried out by evaluating the inhibitory effects of CAPE on neutrophil and monocyte migration in vitro.

Results: CAPE inhibited the expression of IL-6, MCP-1 and ICAM-1 induced by the pro-inflammatory cytokine IL-1β in corneal fibroblasts. The activation of AKT and NF-κB by IL-1β was markedly inhibited by CAPE, whereas the activity of mitogen-activated protein kinases (MAPKs) was not affected. CAPE significantly suppressed the IL-1β-induced migration of differentiated (d)HL-60 and THP-1 cells.

Discussion: These anti-inflammatory effects of CAPE may be expected to inhibit the infiltration of leukocytes into the corneal stroma in vivo.  相似文献   


20.
Background: Several demographic events have been postulated to explain the contemporaneous structure of European genetic diversity. First, an initial settlement of the continent by anatomically modern humans; second, the re-settlement of northern latitudes after the Last Glacial Maximum; third, the demic diffusion of Neolithic farmers from the Near East; and, fourth, several historical events such as the Slavic migration.

Aim: The aim of this study was to provide a more integrated picture of male-specific genetic relationships of Slovakia within the broader pan-European genetic landscape.

Subjects and methods: This study analysed a new Y-chromosome data-set (156 individuals) for both SNP and STR polymorphisms in population samples from five different Slovakian localities.

Results: It was found that the male diversity of Slovakia is embedded in the clinal pattern of the major R1a and R1b clades extending over the continent and a similar pattern of population structure is found with Y-specific SNP or STR variation.

Conclusion: The highly significant correlation between the results based on fast evolving STRs on one hand and slow evolving SNPs on the other hand suggests a recent timeframe for the settlement of the area.  相似文献   


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