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1.
Diabetes Metab Syndr Obes ; 17: 1739-1747, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645656

RESUMO

Aim: Pituitary stalk interruption syndrome is a relatively rare disease. Patients with this disease usually have different degrees of short stature in adulthood. The purpose of this case report is to highlight a special case of unusually elongated limbs with excessive height growth and congenital absence of uterus and ovary, so as to improve clinicians understanding of the atypical manifestations of pituitary stalk interruption syndrome and provide reference for the clinical diagnosis and treatment of the disease. Case Presentation: The 30-year-old female patient exhibited disproportionate growth in height, with a significant increase from 140 cm at the age of 16 to 180 cm currently. Physical examination revealed widened bilateral eye fissures, underdeveloped secondary sexual characteristics, and absence of menstruation. The patient 's parents are cousins, belonging to consanguineous marriage. The patient 's hypoglycemia provocation test suggested the lack of growth hormone and cortisol. Gonadorelin provocation test suggested hypogonadism, and thyroid function test showed hypothyroidism. Pituitary MRI plain scan and enhancement suggested pituitary stalk interruption syndrome, and abdominal and urinary color Doppler ultrasound suggested no echo of uterus and bilateral appendages in the pelvic cavity. The karyotype of peripheral blood was 45, X[3] / 46, XX [117]. The patient was diagnosed with pituitary stalk interruption syndrome, congenital uterine and ovarian deficiency, bone overgrowth, hypothyroidism and secondary osteoporosis. During hospitalization, the symptoms were improved and discharged after hormone replacement therapy such as physiological dose of glucocorticoid, estradiol valerate tablets and levothyroxine sodium tablets. Now the patient is still in our hospital endocrinology outpatient follow-up, no special discomfort. Conclusion: The patient had special clinical manifestations and was clinically confirmed as pituitary stalk interruption syndrome. The patient 's height continues to grow in the absence of growth hormone in the body, and its mechanism remains to be further studied.

2.
Plants (Basel) ; 12(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36771610

RESUMO

Nursery cultivation practices can be modified to increase resistance to water stress in forest seedlings following field establishment, which may be increasingly important under climate change. We evaluated the morphological (survival, growth) and physiological (chlorophyll fluorescence, leaf water potential) responses to water stress for three ecologically diverse Quercus species (Q. robur, Q. pubescens, and Q. ilex) with varying traits resulting from the combination of growing media (peat, coir) and fertilization (standard, P-enriched, K-enriched). For all species under water stress, seedlings grown in coir had generally higher growth than those grown in peat. Seedlings fertilized with P performed better, particularly for survival; conversely, K fertilization resulted in inconsistent findings. Such results could be explained by a combination of factors. P fertilization resulted in higher P accumulation in seedlings, while no K accumulation was observed in K fertilized seedlings. As expected, the more drought-sensitive species, Q. robur, showed the worst response, while Q. pubescens had a drought resistance equal or better to Q. ilex despite being classified as intermediate in drought resistance in Mediterranean environments.

3.
Front Nutr ; 10: 1081896, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819672

RESUMO

Objective: To investigate how serum 25-hydroxyvitamin D (25[OH]D) affects height growth velocity and the risk of low bone mineral density (BMD) in children. Design: A population-based prospective cohort study. Patients and methods: A total of 10 450 participants with complete follow-up records from a cohort were included in the current study. Serum 25(OH)D concentrations were measured at baseline and 2-year follow-up, and the average of 2-time measurements was used for analysis. Low BMD was defined as calcaneus speed of sound Z-score ≤ -1. The associations of vitamin D with height growth velocity and the risks of incident low BMD were evaluated using adjusted ß and risk ratio (RR). Results: After multivariable adjustment, an inverse L-shaped association between serum 25(OH)D concentrations and height growth velocity was observed, leveling off up to 40-60 nmol/L. Overall, each 10 nmol/L higher serum 25(OH)D concentration was associated with a 0.15 cm/year higher height growth velocity (P < 0.001) and a 7% decreased risk of low BMD [RR (95%CI): 0.93 (0.87~0.98)]. Compared to those with vitamin D deficiency, participants who had sufficient vitamin D had a 22% lower risk for low BMD [RR(95%CI): 0.78 (0.62~0.98)]. However, no significant associations between vitamin D and the risk of low BMD were found in overweight and obese children. Conclusion: These findings highlight the importance of maintenance of sufficient 25(OH)D concentrations and healthy body weight during childhood in height growth and bone health promotion.

4.
J Family Med Prim Care ; 12(12): 3279-3284, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38361874

RESUMO

Introduction: An important indicator that plays a pivotal role in examining the health of individuals living in a community is their height. The aim of this study was to examine the relationship between lifestyle and height among female high school students in Dezful, Iran. Methods: This research was a cross-sectional descriptive-analytical study. Participants included 351 female high school students who were selected from public and private high schools in Dezful using random cluster sampling. Miller-Smith Lifestyle Assessment Inventory was used to collect data about students' lifestyles, and their height was measured based on self-report. Results: The total lifestyle score of the study participants was 52.23 ± 11.31. Also, 30.2%, 67.2%, and 2.6% of the students had high, moderate, and low lifestyle scores, respectively. A negative and significant relationship was observed between the total score of lifestyle and its components, that is, nutrition, sleep, exercise, and mental stress, and the height growth of female high school students in Dezful (P < 0.05) according to Pearson's correlation. Results of regression analysis showed that the total lifestyle score and its components could significantly predict the height growth of students. Conclusion: Our results are indicative of the relationship between lifestyle and its components with height growth among female high school students.

5.
Nutrients ; 14(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36014831

RESUMO

Vitamin D is essential for calcium absorption and bone homeostasis. Although short-stature children were reported to have low vitamin D concentrations, there is no clear evidence of a link between vitamin D and height growth in young children not limited to those with short stature. We collected height and weight data at 2 and 4 years of age, serum vitamin D concentrations at 4 years, and questionnaire results on sun exposure from the Japan Environment and Children's Study (JECS). We then analyzed the relationship between vitamin D deficiency and height growth. We also analyzed the correlation between serum vitamin D concentration and sun exposure. Overall, 3624 participants from JECS were analyzed. We identified cases of subclinical vitamin D deficiency and insufficiency. We further found that definitive vitamin D deficiency (<10 ng/mL) impaired height growth by 0.6 cm per year even in young children not limited to those with short stature. Furthermore, we clarified that children with vitamin D deficiency had reduced outdoor activity, especially during winter. In children with either short or normal stature, definitive vitamin D deficiency was associated with height growth decline, and reduction in outdoor activity, especially during winter, was a risk factor for vitamin D deficiency.


Assuntos
Deficiência de Vitamina D , Estatura , Criança , Pré-Escolar , Humanos , Japão/epidemiologia , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Vitaminas
6.
Genes (Basel) ; 13(4)2022 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-35456516

RESUMO

We use Mendelian randomization to estimate the causal effect of age at menarche on late pubertal height growth and total pubertal height growth. The instrument SNPs selected from the exposure genome-wide association study (GWAS) are validated in additional population-matched exposure GWASs. Based on the inverse variance weighting method, there is a positive causal relationship of age at menarche on late pubertal growth (ß^=0.56, 95% CI: (0.34, 0.78), p=3.16×10-7) and on total pubertal growth (ß^=0.36, 95% CI: (0.14, 0.58), p=1.30×10-3). If the instrument SNPs are not validated in additional exposure GWASs, the estimated effect on late pubertal height growth increases by 3.6% to ß^=0.58 (95% CI: (0.42, 0.73), p=4.38×10-13) while the estimates on total pubertal height growth increases by 41.7% to ß^=0.51 (95% CI: (0.35, 0.67), p=2.96×10-11).


Assuntos
Menarca , Análise da Randomização Mendeliana , Causalidade , Feminino , Estudo de Associação Genômica Ampla , Humanos , Menarca/genética , Análise da Randomização Mendeliana/métodos , Polimorfismo de Nucleotídeo Único
7.
Children (Basel) ; 9(1)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35053736

RESUMO

Gonadotropin-releasing hormone agonist (GnRHa) therapy is used to control puberty progression and it preserves height potential in patients with idiopathic central precocious puberty (ICPP). This study evaluated the correlation between weight and height gain at menarche following GnRHa treatment among girls with ICPP and relatively central early puberty (EP). We investigated height/weight trends and changes in height from diagnosis to menarche in girls with ICPP and EP treated with GnRHa. The mean difference in height (Δheight) from treatment cessation to menarche was 9.79 ± 3.53 cm. Girls were divided into girls with Δheight ≥ 9.79 cm (Group 1) and girls with Δheight < 9.79 cm (Group 2). Although near adult height was significantly higher in Group 1, the mean body mass index (BMI) and weight were significantly lower at diagnosis, treatment discontinuation, and menarche. The BMI and weight at the three time points were negatively correlated with height. Girls with higher BMI at all three time points had slower growth rates during the study period. Considering that BMI and body weight were closely related to Δheight, proper management of BMI and body weight of girls receiving early puberty treatment might contribute to growth during and after GnRHa treatment.

8.
Glob Chang Biol ; 28(5): 1903-1918, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34873797

RESUMO

The boreal forest represents the terrestrial biome most heavily affected by climate change. However, no consensus exists regarding the impacts of these changes on the growth of tree species therein. Moreover, assessments of young tree responses in metrics transposable to forest management remain scarce. Here, we assessed the impacts of climate change on black spruce (Picea mariana [Miller] BSP) and jack pine (Pinus banksiana Lambert) growth, two dominant tree species in boreal forests of North America. Starting with a retrospective analysis including data from 2591 black spruces and 890 jack pines, we forecasted trends in 30-year height growth at the transitions from closed to open boreal coniferous forests in Québec, Canada. We considered three variables: (1) height growth, rarely used, but better-reflecting site potential than other growth proxies, (2) climate normals corresponding to the growth period of each stem, and (3) site type (as a function of texture, stoniness, and drainage), which can modify the effects of climate on tree growth. We found a positive effect of vapor pressure deficit on the growth of both species, although the effect on black spruce leveled off. For black spruce, temperatures had a positive effect on the height at 30 years, which was attenuated when and where climatic conditions became drier. Conversely, drought had a positive effect on height under cold conditions and a negative effect under warm conditions. Spruce growth was also better on mesic than on rocky and sub-hydric sites. For portions of the study areas with projected future climate within the calibration range, median height-change varied from 10 to 31% for black spruce and from 5 to 31% for jack pine, depending on the period and climate scenario. As projected increases are relatively small, they may not be sufficient to compensate for potential increases in future disturbances like forest fires.


Assuntos
Picea , Pinus , Mudança Climática , Picea/fisiologia , Pinus/fisiologia , Estudos Retrospectivos , Taiga , Árvores
9.
J Pediatr Endocrinol Metab ; 34(6): 733-739, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33856747

RESUMO

OBJECTIVES: Gonadotropin-releasing hormone agonist treatment is important for optimal growth in girls with central precocious puberty (CPP). Data are lacking regarding benefit to height outcome when treatment is started after chronological age (CA) of 7 years, and if continued beyond CA of 10 years or bone age (BA) of 12 years. METHODS: Forty-eight girls with CPP were treated with monthly leuprolide depot. Change in predicted adult height (PAH) during treatment was assessed. Changes in PAH and growth velocity were compared between girls initiating treatment at CA <7 vs. ≥7 years, and BA ≥12 vs. BA <12 years. RESULTS: Mean baseline CA was 6.8 years, BA, 10.2 years; and PAH, 156.4 cm. BA/CA ratio decreased from pretreatment values, averaging 1.5 to 1.2 at the end of treatment. Proportion of girls with >5 cm PAH change during treatment was similar, and PAH increased throughout treatment in most girls, regardless of age at treatment initiation. PAH continued to increase in 16/19 girls who continued treatment after BA of 12 years, and also in 16/22 girls who continued treatment after CA of 10 years. CONCLUSIONS: PAH improved in most girls who initiated treatment after CA of 7 years. It continued to improve in most girls with longer treatment, even past BA of 12 years or CA of 10 years, which suggests that no absolute CA or BA limit should define initiation or end of treatment. Treatment plans need to be individualized, and neither treatment initiation nor cessation should be based on BA or CA alone.


Assuntos
Estatura/efeitos dos fármacos , Desenvolvimento Ósseo , Hormônio Liberador de Gonadotropina/agonistas , Puberdade Precoce/tratamento farmacológico , Criança , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Prognóstico , Puberdade Precoce/patologia
10.
Front Genet ; 12: 596749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868361

RESUMO

The study on the fast-growing traits of trees, mainly valued by tree height (TH) and diameter at breast height (DBH), is of great significance to promote the development of the forest industry. Quantitative trait locus (QTL) mapping based on high-density genetic maps is an efficient approach to identify genetic regions for fast-growing traits. In our study, a high-density genetic map for the F1 population was constructed. The genetic map had a total size of 5,484.07 centimorgan (cM), containing 5,956 single nucleotide polymorphisms (SNPs) based on Specific Length Amplified Fragment sequencing. Six fast-growing related stable QTL were identified on six chromosomes, and five stable QTL were identified by a principal component analysis (PCA). By combining the RNA-seq analysis for the two parents and two progenies with the qRT-PCR analysis, four candidate genes, annotated as DnaJ, 1-aminocyclopropane-1-carboxylate oxidase 1 (ACO1), Caffeic acid 3-O-methyltransferase 1 (COMT1), and Dirigent protein 6 (DIR6), that may regulate height growth were identified. Several lignin biosynthesis-related genes that may take part in height growth were detected. In addition, 21 hotspots in this population were found. The results of this study will provide an important foundation for further studies on the molecular and genetic regulation of TH and DBH.

11.
Front Pharmacol ; 11: 597885, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324225

RESUMO

Atopic dermatitis is a chronic inflammatory skin disease that affects the growth and development of children. The prevalence of atopic dermatitis has been continually increasing, and this has also been accompanied by rising socioeconomic costs. Interest has been growing in alternative medicine as a means of alleviating the burden of atopic dermatitis. This was a single-center, double-blinded, randomized, placebo-controlled investigator-led clinical trial including 60 atopic dermatitis patients. The participants were classified into an experimental group (30 persons) and a control group (30 persons), who were administered, respectively, socheongryong-tang or a placebo for 4 weeks. After 4 weeks of treatment, the participants visited the trial center again and assess their efficacy and safety. The researchers performed statistical comparisons of the changes in the SCORAD Index, amount and frequency of ointment use, and height and weight to assess the efficacy. To assess the safety, diagnostic tests and vital sign checks were performed at each visit, and the presence or absence of adverse events was observed. As a result, the frequency and the amount of steroid ointment application in both groups increased, but the experimental group showed less tendency (p = 0.081). Results of analyzing the children in the experimental group in relation to growth showed a significantly greater height growth than the control group (p < 0.05). In addition, all study participants did not show any remarkable abnormal signs in the safety evaluation. In conclusion, compared to the control group, the experimental group, who took socheongryong-tang showed a tendency to be less dependent on steroid ointment and statistically significant increase in height.

12.
Acta amaz ; 50(3): 192-198, jul. - set. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118817

RESUMO

Enrichment plantings into secondary forest are an important option in restoring species diversity and ecosystem services. However, little attention has been given to environmental requirements for species performance. This study evaluated the effects of lightgaps and topographic position on the growth and survival of four native tree species (Pouteria caimito, Garcinia macrophylla, Dipteryx odorata and Cynometra bauhiniaefolia) planted into a 26-year old secondary forest originating from abandoned pastures in the central Amazon Basin. Artificial lightgaps and control plots under closed canopy were uniformly distributed on plateaus and bottomlands near water bodies. Seedlings were planted randomly into the plots and monitored for 28 months. Seedling survival rate was high (93%) and did not differ among species. Overall, lightgaps produced a 38% increase in seedling height relative to the controls. Although the four species naturally occur in mature forest, two of the four grew significantly more in lightgaps than in closed canopy secondary forest. Overall, bottomlands facilitated greater seedling growth in height (38%) relative to plateaus, but only one species exhibited a significant increase. This study shows the importance of the environmental variability generated with canopy openings along the topographic gradient, suggesting that both the selection of species and microsite conditions of planting sites have to be considered important criteria in the recovery of degraded areas. (AU)


Assuntos
Produção Agrícola , Pastagens , Ecossistema Amazônico , Recuperação e Remediação Ambiental
13.
Mol Genet Genomic Med ; 7(12): e988, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31566922

RESUMO

BACKGROUND: Pathogenic variants of ANKRD11 have been reported to cause KBG syndrome characterized by short stature, characteristic facial appearance, intellectual disability, macrodontia, and skeletal anomalies. However, the direct clinical relevance of ANKRD11 mutation with short stature is yet unknown. METHODS: Here, we report a Chinese boy with idiopathic short stature (ISS) based on clinical and genetic characteristics. Comprehensive medical evaluations were performed including metabolic studies, endocrine function tests, bone X-rays, and echocardiography. Whole-exome and Sanger sequencing was used to detect and confirm genetic mutations associated with short stature in this patient, respectively. The pathogenicity of the variant was further predicted by several in silico prediction tools and repositories of sequence variation. Twenty-four months follow-up was performed to observe the growth rate of the patient treated with recombinant human growth hormone (GH). RESULTS: One heterozygous point mutation (c.2579C>T) was confirmed in the ANKRD11 gene of the patient and inherited from his mother. This mutation site was located within the highly conservative region of ANKRD11 protein and predicted to be possibly damaging in several in silico prediction programs and repositories of sequence variation. Additionally, patient underwent GH replacement therapy for 24 months exhibited good response to the treatment. CONCLUSION: A heterozygous point mutation of AKNRD11 gene was identified in a Chinese patient with short stature phenotype. The patient was treated effectively with GH supplementation.


Assuntos
Nanismo/genética , Receptores de Glutamato/genética , Proteínas Repressoras/genética , Adulto , Povo Asiático/genética , Criança , China , Família , Feminino , Estudos de Associação Genética , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Linhagem , Fenótipo , Mutação Puntual/genética , Polimorfismo de Nucleotídeo Único/genética
14.
BMC Pediatr ; 19(1): 287, 2019 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-31421667

RESUMO

BACKGROUND: Antiretroviral treatment (ART) has been shown to have a beneficial effect on the weight evolution but its effect on height remains unclear. We described patterns of height evolution and identified predictors of catch-up growth in HIV-infected children on ART. METHODS: To describe the height evolution from birth to adulthood, we developed a nonlinear mixed effect model using data from perinatally HIV-infected children who initiated ART from 1999 to 2013 in a prospective cohort study in Thailand. The main covariates of interest were: sex, ART regimen (dual nucleoside reverse-transcriptase inhibitor, non-nucleoside reverse transcriptase inhibitor (NNRTI)-, or protease inhibitor (PI)-based), baseline CD4 percentage, HIV-RNA load and CDC HIV Classification stage and occurrence of AIDS-defining events. RESULTS: A total 477 children (43% boys) contributed 18,596 height measurements over a median duration of 6.3 years on ART (interquartile range, 3.0 to 8.3). At ART initiation, median age was 6.2 years (1.8 to 9.6), 16% of children were underweight (weight-for-age z-score < - 2), 49% presented stunting (height-for-age z-score < - 2), and 7% wasting (weight-for-height z-score < - 2). The most frequent regimen at ART initiation was NNRTI-based (79%). A model with 4 components, birth length and 3 exponential functions of age accounting for the 3 growth phases was developed and show that the height-growth velocity was inversely associated with the age at ART initiation, the adult height was significantly lower in those who had experienced at least one AIDS-defining event while, as expected, the model found that adult height in females was lower than in males. Age at ART initiation, type of ART regimen, CDC stage, CD4 percentages, and HIV-RNA load were not associated with the final height. CONCLUSIONS: The younger the children at ART initiation, the greater the effect on height-growth velocity, supporting the World Health Organization's recommendation to start ART as early as possible. However, final adult height was not linked to the age at ART initiation.


Assuntos
Antirretrovirais/uso terapêutico , Estatura/efeitos dos fármacos , Crescimento/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Peso Corporal/efeitos dos fármacos , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Feminino , Seguimentos , Transtornos do Crescimento , Infecções por HIV/sangue , Infecções por HIV/mortalidade , Humanos , Lactente , Perda de Seguimento , Masculino , Modelos Estatísticos , Estudos Prospectivos , Inibidores da Transcriptase Reversa/uso terapêutico , Fatores Sexuais , Estatísticas não Paramétricas , Tailândia , Magreza , Síndrome de Emaciação
15.
Am J Clin Nutr ; 109(4): 1154-1163, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30869114

RESUMO

BACKGROUND: Early protein intake may program later body composition and height growth, perhaps mediated by insulin-like growth factor I (IGF-I). In infancy, higher protein intake is consistently associated with higher IGF-I concentrations and more rapid growth, but associations of protein intake after infancy with later growth and IGF-I are less clear. OBJECTIVES: Our objective was to examine associations of protein intake in early childhood (median 3.2 y) with height, IGF-I, and measures of adiposity and lean mass in mid-childhood (median 7.7 y) and early adolescence (median 13.0 y), and with changes in these outcomes over time. We hypothesized that early childhood protein intake programs later growth. METHODS: We studied 1165 children in the Boston-area Project Viva cohort. Mothers reported children's diet using food-frequency questionnaires. We stratified by child sex and examined associations of early childhood protein intake with mid-childhood and early adolescent BMI z score, skinfold thicknesses, dual-energy X-ray absorptiometry (DXA) fat mass, DXA lean mass, height z score, and IGF-I concentration. We adjusted linear regression models for race/ethnicity, family sociodemographics, parental and birth anthropometrics, breastfeeding status, physical activity, and fast food intake. RESULTS: Mean protein intake in early childhood was 58.3 g/d. There were no associations of protein intake in early childhood with any of the mid-childhood outcomes. Among boys, however, each 10-g increase in early childhood total protein intake was associated with several markers of early adolescent size, namely BMI z score (0.12 higher; 95% CI: 0.01, 0.23), DXA lean mass index (1.34% higher; 95% CI: -0.07%, 2.78%), and circulating IGF-I (5.67% higher; 95% CI: 0.30%, 11.3%). There were no associations with fat mass and no associations with any adolescent outcomes among girls. CONCLUSIONS: Early childhood protein intake may contribute to programming lean mass and IGF-I around the time of puberty in boys, but not to adiposity development. This study was registered at clinicaltrials.gov as NCT02820402.


Assuntos
Composição Corporal , Desenvolvimento Infantil , Proteínas Alimentares/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Adiposidade , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Proteínas Alimentares/análise , Feminino , Humanos , Fator de Crescimento Insulin-Like I/genética , Masculino , Estudos Prospectivos
16.
Oecologia ; 189(2): 317-328, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30612226

RESUMO

Because tree size and age co-vary, it is difficult to separate their effects on growth and physiological function. To infer causes for age-related height-growth decline, we compared various leaf traits between mature (ca. 100 years) and old (ca. 300 years) trees of Pinus densiflora, having similar heights (ca. 30 m) and growing in the same stand. For many leaf traits, mature and old trees showed similar height-related trends reflecting acclimation to height-related hydraulic limitation for maintaining photosynthetic and hydraulic homeostasis. Photosynthetic capacity was constant within crowns of both age-classes, though 4.9-5.4 µmol CO2 m-2 s-1 lower for old than for mature trees. Biochemical acclimation of photosynthesis, allocating more nitrogen to treetop leaves, was observed only for mature trees. Leaf turgor loss point was also constant within crowns of both age-classes with no significant effect of age on leaf hydraulic traits. In mature trees, leaf capacitance increased, while bulk tissue elastic modulus decreased with height, whereas opposite height-related trends were observed for old trees. For both age-classes, leaf mass per area (LMA), transfusion-tissue area, and xylem area all increased with height, but LMA was ca. 30 g m-2 greater for old than for mature trees. In old trees, mesophyll area decreased with height, suggesting anatomical acclimation to height may negatively affect photosynthetic capacity. We inferred that old trees rely more on morphological than biochemical acclimation and that such post-maturational shift in resource allocation could underlie height-growth decline of P. densiflora after reproductive maturity.


Assuntos
Fotossíntese , Pinus , Homeostase , Folhas de Planta , Árvores
17.
J Expo Sci Environ Epidemiol ; 29(1): 109-117, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30185943

RESUMO

BACKGROUND: Bisphenol A (BPA) is an environmental endocrine disruptor and is found in many consumer products. Studies suggest that BPA may perturb pubertal development, although evidence on BPA-influenced pubertal height growth is scarce. METHODS: A total of 754 children aged 9-18 years from three schools (one elementary, one middle, and one high school) in Shanghai were included in this longitudinal study. Height was measured at enrolment (visit 1) and, subsequently, at 19 months after enrolment (visit 2). Age- and sex-specific Z scores for height were calculated (height Z score = [participant's height-sex- and age-specific population height mean]/sex- and age-specific population height standard deviation). Urine samples were collected at enrolment to measure BPA concentrations. We used multiple linear regression models or general estimating equation models (GEE) to estimate associations between urine BPA level and height Z score. RESULTS: The geometric mean of urine BPA concentrations was 1.6 µg/L (95%CI: 1.4, 1.8) or 1.2 µg/g creatinine (95%CI: 1.0, 1.3). An inverse association between urine BPA level and height was observed in boys. After adjustment for potential confounders, height Z score at enrolment in boys decreased by 0.49 for the highest exposure level (above 10.9 µg/g creatinine as the 90th percentile), compared with the lowest BPA exposure (below 0.2 µg/g creatinine as the 25th percentile) (95%CI: -0.96, -0.01; p-trend = 0.024). The inverse association remained between BPA exposure and height Z score at visit 2. The GEE model showed that a 1-unit increase in log10-transformed BPA concentrations was associated with a 0.15-point decrease in height Z score over the follow-up (95%CI: -0.30, -0.01). BPA was not associated with height growth in girls. CONCLUSIONS: Our findings indicate an inverse association between urine BPA level and height growth in boys. These findings need to be confirmed in further studies.


Assuntos
Compostos Benzidrílicos/urina , Disruptores Endócrinos/urina , Poluentes Ambientais/urina , Fenóis/urina , Puberdade/urina , Adolescente , Criança , China , Creatinina/urina , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-817931

RESUMO

The weight development can be used to indicate children's nutritional status. But the assessment of stature development in children is more complicated,which involves genetics,endocrine,nutrition and bone metabolism. Parents should regularly follow up on the growth and development of children. At the same time,the growth data of children should be kept by parents. Pediatricians can obtain important information from the child's development history to help assessment and diagnosis. Before dealing with this thorny problems of social and medical confusion,primary care pediatricians(PCP)should learn the knowledge of height growth during childhood,including the normal range and rules of height growth. Meanwhile,PCP need to understand the factors affecting the height growth in order to make proper management.

19.
Acta amaz ; 48(3): 179-190, July-Sept. 2018. ilus, map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455369

RESUMO

This paper presents a novel approach for estimating the height of individual trees in secondary forests at two study sites: Manaus (central Amazon) and Santarém (eastern Amazon) in the Brazilian Amazon region. The approach consists of adjusting tree height-diameter at breast height (H:DBH) models in each study site by ecological species groups: pioneers, early secondary, and late secondary. Overall, the DBH and corresponding height (H) of 1,178 individual trees were measured during two field campaigns: August 2014 in Manaus and September 2015 in Santarém. We tested the five most commonly used log-linear and nonlinear H:DBH models, as determined by the available literature. The hyperbolic model: H = a.DBH/(b+DBH) was found to present the best fit when evaluated using validation data. Significant differences in the fitted parameters were found between pioneer and secondary species from Manaus and Santarém by F-test, meaning that site-specific and also ecological-group H:DBH models should be used to more accurately predict H as a function of DBH. This novel approach provides specific equations to estimate height of secondary forest trees for particular sites and ecological species groups. The presented set of equations will allow better biomass and carbon stock estimates in secondary forests of the Brazilian Amazon.


Este trabalho apresenta uma nova abordagem para a estimativa de altura de árvores em florestas secundárias em duas áreas de estudo na Amazônia brasileira: Manaus (Amazônia central) e Santarém (Amazônia oriental). A abordagem consistiu em ajustar modelos hipsométricos separados por área de estudo e grupos ecológicos de espécies: pioneiras, secundárias iniciais e secundárias tardias. No total, 1178 árvores foram medidas em diâmetro e altura em duas etapas de campo: agosto de 2014 em Manaus e Setembro de 2015 em Santarém. Foram testados cinco modelos log-lineares e não lineares mais utilizados na literatura. O modelo hiperbólico: H = a.D/(b+D) foi o que apresentou o melhor ajuste quando avaliado com os dados de validação. Diferenças significativas nos parâmetros de ajuste foram observadas entre as espécies pioneiras e secundárias de Manaus e Santarém pelo teste F, significando que equações específicas por grupos ecológicos e área de estudo deveriam ser utilizadas para estimar a altura (H) a partir do diâmetro (D) com maior acurácia. Esta nova abordagem fornece equações específicas para localidade e grupo ecológico, para estimar a altura das árvores em florestas secundárias. O conjunto de equações desenvolvidas permitirá melhorar as estimativas de biomassa e a quantificação dos estoques de carbono nas florestas secundárias da Amazônia brasileira.


Assuntos
Biometria/métodos , Estatística como Assunto , Árvores/anatomia & histologia , Dinâmica não Linear , Modelos Lineares
20.
Am J Respir Crit Care Med ; 198(12): 1539-1548, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29995435

RESUMO

Rationale: Puberty may influence lung function, but the precise role of pubertal height growth in lung development is unclear.Objectives: To examine associations of timing of puberty and peak velocity of pubertal height growth with lung function in adolescence and early adulthood.Methods: Longitudinal analyses of repeat height measurements from age 5 to 20 years for a British birth cohort with 4,772 males and 4,849 females were conducted to characterize height growth trajectories and to derive pubertal age and peak height velocity using the validated SITAR (SuperImposition by Translation and Rotation) model. Association of these estimates with prebronchodilator and post-bronchodilator spirometry measures: FEV1; FVC; FEV1/FVC; FEF25-75% at age 15 and 24 years were investigated using multivariable regression models adjusted for lung function at age 8 years, height and age at time of outcome measurements, and potential confounders.Measurements and Main Results: Later pubertal age and greater peak velocity were associated with higher FEV1 and FVC at 24 years in both sexes. A 1-year increase in pubertal age was associated with a 263-ml higher FVC (95% confidence interval [CI], 167-360 ml) for males (n = 567) and 100-ml (95% CI, 50-150 ml) higher FVC for females (n = 990). A 1-cm/yr increase in peak velocity was associated with 145-ml (95% CI, 56-234 ml) and 50-ml (95% CI, 2-99 ml) increases in FVC for males and females, respectively. No associations were found with FEV1/FVC.Conclusions: Later onset and greater peak velocity of height growth in puberty are associated with increased FEV1 and FVC in young adults but there was no evidence of dysanapsis of pubertal lung growth.


Assuntos
Estatura , Crescimento/fisiologia , Pulmão/fisiologia , Puberdade/fisiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes de Função Respiratória , Adulto Jovem
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