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1.
Spine Deform ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935264

ABSTRACT

INTRODUCTION: Since the outbreak of the COVID-19 pandemic, reduction of social activities and rapid adoption of telemedicine, decreasing face-to-face encounters seems to have negatively affected the timely Idiopathic Scoliosis (IS) referral with a spine specialist. We aim to document the progression of IS curves during COVID-19 pandemic reflected by the late presentation of patients at the initial visit with higher Cobb angles and to evaluate its influence on health-related quality of life scores. MATERIALS AND METHODS: All IS patients scheduled for surgery between April 2019 and September 2021 were recruited in a prospective cohort study. The patients were divided into five cohorts of 6 month duration each according to their booking date: 2 periods before the 1st COVID-19 wave, one period during and two periods afterwards. In each cohort, patients were divided into 3: those who were scheduled for posterior spinal fusion (PSF) at 1st visit, those booked for vertebral body tethering (VBT) at 1st visit, and those scheduled for surgery but who have failed brace treatment. Variables included age, gender, Risser grade and preoperative SRS-22 scores. Chi2 and ANOVA tests were used for comparison. RESULTS: 173 patients were analyzed. 33 patients (13.1 ± 3 y.o.) were scheduled between Apr and Sept 2019; 38 (13.1 y.o. ± 2) between Oct 2019 and Mar 2020; 31 (13.4 ± 3 y.o.) between Apr and Sept 2020; 30 (14.3 ± 2 y.o.) between Sept 2020 and Mar 2021; and 41 patients (13.8 ± 2 y.o.) between Apr and Sept 2021. Non-statistically significant differences were found between periods before, during or after the COVID-19 first wave regarding patients' age, gender, Risser grade and SRS-22 scores. Average Cobb angles of patients at their 1st visit after the beginning of the COVID-19 pandemic were significantly higher than those before COVID-19 (52.2° ± 7° and 56.6° ± 13° vs 47.8° ± 12° and 45.2° ± 13°; p = 0.0001). More patients were booked for PSF (p < 0.0000) through the five evaluated periods, while the indication of VBT or surgery in patients previously braced progressively decreased. CONCLUSION: Patients presented at the scoliosis clinic for the 1st time after the 1st COVID-19 wave with significantly larger Cobb angles, and likely contributed to an increased proportion of PSF, as the potential window for bracing or VBT was missed due to a delayed consultation.

2.
Aquat Toxicol ; 271: 106940, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38728927

ABSTRACT

Aminomethylphosphonic acid (AMPA) is the main metabolite in the degradation of glyphosate, a broad-spectrum herbicide, and it is more toxic and persistent in the environment than the glyphosate itself. Owing to their extensive use, both chemicals pose a serious risk to aquatic ecosystems. Here, we explored the genotoxicological and physiological effects of glyphosate, AMPA, and the mixed solution in the proportion 1:1 in Lymnaea stagnalis, a freshwater gastropod snail. To do this, adult individuals were exposed to increasing nominal concentrations (0.0125, 0.025, 0.050, 0.100, 0.250, 0.500 µg/mL) in all three treatments once a week for four weeks. The genotoxicological effects were estimated as genomic damage, as defined by the number of micronuclei and nuclear buds observed in hemocytes, while the physiological effects were estimated as the effects on somatic growth and egg production. Exposure to glyphosate, AMPA, and the mixed solution caused genomic damage, as measured in increased frequency of micronuclei and nuclear buds and in adverse effects on somatic growth and egg production. Our findings suggest the need for more research into the harmful and synergistic effects of glyphosate and AMPA and of pesticides and their metabolites in general.


Subject(s)
Glycine , Glyphosate , Herbicides , Lymnaea , Organophosphonates , Water Pollutants, Chemical , Animals , Glycine/analogs & derivatives , Glycine/toxicity , Lymnaea/drug effects , Lymnaea/genetics , Water Pollutants, Chemical/toxicity , Organophosphonates/toxicity , Herbicides/toxicity , Micronucleus Tests , DNA Damage/drug effects , Hemocytes/drug effects , Tetrazoles/toxicity
3.
Aging Cell ; 23(4): e14157, 2024 04.
Article in English | MEDLINE | ID: mdl-38558485

ABSTRACT

A recently proposed principal law of lifespan (PLOSP) proposes to extend the whole human lifespan by elongating different life stages. As the preborn stage of a human being, gestation is the foundation for the healthy development of the human body. The antagonistic pleiotropy (AP) theory of aging states that there is a trade-off between early life fitness and late-life mortality. The question is whether slower development during the gestation period would be associated with a longer lifespan. Among all living creatures, the length of the gestation period is highly positively correlated to the length of the lifespan, although such a correlation is thought to be influenced by the body sizes of different species. While examining the relationship between lifespan length and body size within the same species, dogs exhibit a negative correlation between lifespans and body sizes, while there is no such correlation among domestic cats. For humans, most adverse gestational environments shorten the period of gestation, and their impacts are long-term. While many issues remain unsolved, various developmental features have been linked to the conditions during the gestation period. Given that the length of human pregnancies can vary randomly by as long as 5 weeks, it is worth investigating whether a slow steady healthy gestation over a longer period will be related to a longer and healthier lifespan. This article discusses the potential benefits, negative impacts, and challenges of the relative elongation of the gestation period.


Subject(s)
Aging , Longevity , Pregnancy , Female , Humans , Animals , Dogs , Cats , Body Size
4.
Dev Sci ; 27(4): e13493, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38497570

ABSTRACT

During human childhood, brain development and body growth compete for limited metabolic resources, resulting in a trade-off where energy allocated to brain development can decrease as body growth accelerates. This preregistered study explores the relationship between language skills, serving as a proxy for brain development, and body mass index at three distinct developmental stages, representing different phases of body growth. Longitudinal data from 2002 children in the EDEN mother-child cohort were analyzed using structural equation modeling. Our findings reveal a compelling pattern of associations: girls with a delayed adiposity rebound, signaling slower growth rate, demonstrated better language proficiency at ages 5-6. Importantly, this correlation appears to be specific to language skills and does not extend to nonverbal cognitive abilities. Exploratory analyses show that early environmental factors contributing to enhanced cognitive development, such as higher parental socio-economic status and increased cognitive stimulation, are positively associated with both language skills and the timing of adiposity rebound in girls. Overall, our findings lend support to the existence of an energy allocation trade-off mechanism that appears to prioritize language function over body growth investment in girls. RESEARCH HIGHLIGHTS: The high energy demand of neurocognitive development leads to a trade-off in human children between brain growth and other biological functions, including body growth. Previous studies indicate that around age 5, when the brain energy consumption peaks, children typically experience a decrease in body mass known as 'adiposity rebound'. A delayed adiposity rebound, indicating slower growth may be associated with enhanced language abilities in children. Our preregistered study confirms this correlation in girls and further associates early cognitive stimulation with improved language skills and delayed adiposity rebound time.


Subject(s)
Adiposity , Body Mass Index , Brain , Language Development , Humans , Female , Child , Child, Preschool , Male , Adiposity/physiology , Brain/growth & development , Brain/physiology , Cognition/physiology , Longitudinal Studies , Child Development/physiology
5.
Poult Sci ; 103(5): 103628, 2024 May.
Article in English | MEDLINE | ID: mdl-38518667

ABSTRACT

This study sought to determine the relationship among broiler performance, organ development, and indicators of microbiota colonization. A total of 1,200 two-day-old male Ross 308 broiler chicks, divided among 3 cohorts of equal size, were housed in battery cages, and allotted based on body weight. On study d 11, birds were weighed, and birds with BW gain within the 10th and 90th percentiles were assigned to the Slow and Fast groups, respectively. Birds (n = 30 for each group) selected on d 11 were provided water and a corn-soybean meal-based diet ad libitum while maintained individually through study d 25 (i.e., a 14-d growth period). Parameters regarding growth performance, organ and intestine weights and lengths, and intestinal volatile fatty acid concentrations were measured. All data were analyzed by one-way ANOVA using the Mixed procedure of SAS. Fast birds exhibited greater (P < 0.001) BW gain and feed intake than slow birds, but feed conversion ratio (FCR) did not differ (P = 0.19). Additionally, Slow birds had higher (P < 0.05) relative weights (% of BW) for nearly all organs on d 11 and 25, most notably the gizzard, proventriculus, pancreas, and liver. Conversely, intestinal sections were longer (P < 0.05) in the Fast birds. Measurement of gut histomorphology did not show any notable differences between growth rate groups in terms of villi height, crypt depth, or their ratio for either time-point (P > 0.05). In terms of volatile fatty acid concentrations of luminal contents, acetate concentrations were 10.2% higher (P < 0.001) in the ileum of the Slow birds compared with Fast birds on d 25. Overall, the findings suggest that total BW gain is influenced by the development of metabolically active organs, as supported by lower weight gain in Slow birds with relatively larger organ weights and shorter intestinal lengths than their Fast counterparts. The general lack of differences in fermentation end-product concentrations in luminal contents does not rule out influence of the microbiota on growth rate of broilers, which warrants further investigation.


Subject(s)
Chickens , Fermentation , Animals , Chickens/growth & development , Chickens/physiology , Male , Gastrointestinal Microbiome/physiology , Organ Size , Diet/veterinary , Fatty Acids, Volatile/metabolism , Intestines/growth & development , Intestines/anatomy & histology , Animal Feed/analysis , Random Allocation
6.
Cell Rep Med ; 4(9): 101187, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37659411

ABSTRACT

The long-term clinical outcomes of severe obesity due to leptin signaling deficiency are unknown. We carry out a retrospective cross-sectional investigation of a large cohort of children with leptin (LEP), LEP receptor (LEPR), or melanocortin 4 receptor (MC4R) deficiency (n = 145) to evaluate the progression of the disease. The affected individuals undergo physical, clinical, and metabolic evaluations. We report a very high mortality in children with LEP (26%) or LEPR deficiency (9%), mainly due to severe pulmonary and gastrointestinal infections. In addition, 40% of surviving children with LEP or LEPR deficiency experience life-threatening episodes of lung or gastrointestinal infections. Although precision drugs are currently available for LEP and LEPR deficiencies, as yet, they are not accessible in Pakistan. An appreciation of the severe impact of LEP or LEPR deficiency on morbidity and early mortality, educational attainment, and the attendant stigmatization should spur efforts to deliver the available life-saving drugs to these children as a matter of urgency.


Subject(s)
Leptin , Obesity, Morbid , Child , Humans , Cross-Sectional Studies , Morbidity , Retrospective Studies
7.
Clin Transl Med ; 13(6): e1284, 2023 06.
Article in English | MEDLINE | ID: mdl-37323108

ABSTRACT

BACKGROUND: Spinal cord injury (SCI) in young adults leads to severe sensorimotor disabilities as well as slowing of growth. Systemic pro-inflammatory cytokines are associated with growth failure and muscle wasting. Here we investigated whether intravenous (IV) delivery of small extracellular vesicles (sEVs) derived from human mesenchymal stem/stromal cells (MSC) has therapeutic effects on body growth and motor recovery and can modulate inflammatory cytokines following severe SCI in young adult rats. METHODS: Contusional SCI rats were randomized into three different treatment groups (human and rat MSC-sEVs and a PBS group) on day 7 post-SCI. Functional motor recovery and body growth were assessed weekly until day 70 post-SCI. Trafficking of sEVs after IV infusions in vivo, the uptake of sEVs in vitro, macrophage phenotype at the lesion and cytokine levels at the lesion, liver and systemic circulation were also evaluated. RESULTS: An IV delivery of both human and rat MSC-sEVs improved functional motor recovery after SCI and restored normal body growth in young adult SCI rats, indicating a broad therapeutic benefit of MSC-sEVs and a lack of species specificity for these effects. Human MSC-sEVs were selectively taken up by M2 macrophages in vivo and in vitro, consistent with our previous observations of rat MSC-sEV uptake. Furthermore, the infusion of human or rat MSC-sEVs resulted in an increase in the proportion of M2 macrophages and a decrease in the production of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-6 at the injury site, as well as a reduction in systemic serum levels of TNF-α and IL-6 and an increase in growth hormone receptors and IGF-1 levels in the liver. CONCLUSIONS: Both human and rat MSC-sEVs promote the recovery of body growth and motor function after SCI in young adult rats possibly via the cytokine modulation of growth-related hormonal pathways. Thus, MSC-sEVs affect both metabolic and neurological deficits in SCI.


Subject(s)
Extracellular Vesicles , Mesenchymal Stem Cells , Spinal Cord Injuries , Humans , Rats , Animals , Tumor Necrosis Factor-alpha/metabolism , Mesenchymal Stem Cells/metabolism , Spinal Cord Injuries/therapy , Extracellular Vesicles/metabolism , Cytokines/metabolism , Interleukin-6/metabolism
8.
Elife ; 122023 05 09.
Article in English | MEDLINE | ID: mdl-37157843

ABSTRACT

Ectotherms are predicted to 'shrink' with global warming, in line with general growth models and the temperature-size rule (TSR), both predicting smaller adult sizes with warming. However, they also predict faster juvenile growth rates and thus larger size-at-age of young organisms. Hence, the result of warming on the size-structure of a population depends on the interplay between how mortality rate, juvenile- and adult growth rates are affected by warming. Here, we use two-decade long time series of biological samples from a unique enclosed bay heated by cooling water from a nearby nuclear power plant to become 5-10 °C warmer than its reference area. We used growth-increment biochronologies (12,658 reconstructed length-at-age estimates from 2426 individuals) to quantify how >20 years of warming has affected body growth, size-at-age, and catch to quantify mortality rates and population size- and age structure of Eurasian perch (Perca fluviatilis). In the heated area, growth rates were faster for all sizes, and hence size-at-age was larger for all ages, compared to the reference area. While mortality rates were also higher (lowering mean age by 0.4 years), the faster growth rates lead to a 2 cm larger mean size in the heated area. Differences in the size-spectrum exponent (describing how the abundance declines with size) were less clear statistically. Our analyses reveal that mortality, in addition to plastic growth and size-responses, is a key factor determining the size structure of populations exposed to warming. Understanding the mechanisms by which warming affects the size- and the age structure of populations is critical for predicting the impacts of climate change on ecological functions, interactions, and dynamics.


Subject(s)
Ecosystem , Perches , Animals , Hot Temperature , Temperature , Global Warming , Climate Change , Perches/physiology
9.
PeerJ ; 11: e14991, 2023.
Article in English | MEDLINE | ID: mdl-36949764

ABSTRACT

Salmonid species are main actors in the Italian socio-ecological landscape of inland fisheries. We present novel data on the size-age structure of one of the remnant Italian populations of the critically endangered marble trout Salmo marmoratus, which co-occurs with other stocked non-native salmonids in a large glacial river of the Lake Maggiore basin (Northern Italy-Southern Switzerland). Like other Italian native trout populations, the Toce River marble trout population is affected by anthropogenic introgression with the non-native brown trout S. trutta. Our sample includes 579 individuals, mainly collected in the Toce River main channel. We estimated the length-weight relationship, described the population size-age structure, estimated the age-specific growth trajectories, and fit an exponential mortality model. A subset of the sample was also used to measure numerical and biomass density. The estimated asymptotic maximum length is ~105 cm total length (TL). Mean length at first maturity is ~55 cm TL, and mean length at maximum yield per recruit is ~68 cm TL. Approximately 45-70% of the population are estimated to die annually, along with a fishing annual mortality of ~37%, with an exploitation ratio of ~0.5. The frequency distribution of length classes in a sample collected by angling shows that ~80% of the individuals that could be retained according to the current recreational fishing regulations likely never reproduced, and large fish disproportionally contributing to recruitment are fished and retained. We identify possible overfishing risks posed by present regulations, and propose updated harvest-slot length limits to mitigate such risks. More detailed and long-term datasets on this system are needed to more specifically inform the fishery management and monitor the effects of any change in the management strategy on the size-age structure of the marble trout population of the Toce River.


Subject(s)
Salmo salar , Trout , Animals , Conservation of Natural Resources , Fisheries , Italy
10.
Ecology ; 104(4): e3967, 2023 04.
Article in English | MEDLINE | ID: mdl-36565169

ABSTRACT

Body size-dependent physiological effects of temperature influence individual growth, reproduction, and survival, which govern animal population responses to global warming. Considerable knowledge has been established on how such effects can affect population growth and size structure, but less is known of their potential role in temperature-driven adaptation in life-history traits. In this study, we ask how warming affects the optimal allocation of energy between growth and reproduction and disentangle the underlying fitness trade-offs. To this end, we develop a novel dynamic energy budget integral projection model (DEB-IPM), linking individuals' size- and temperature-dependent consumption and maintenance via somatic growth, reproduction, and size-dependent energy allocation to emergent population responses. At the population level, we calculate the long-term population growth rate (fitness) and stable size structure emerging from demographic processes. Applying the model to an example of pike (Esox lucius), we find that optimal energy allocation to growth decreases with warming. Furthermore, we demonstrate how growth, fecundity, and survival contribute to this change in optimal allocation. Higher energy allocation to somatic growth at low temperatures increases fitness through survival of small individuals and through the reproduction of larger individuals. In contrast, at high temperatures, increased allocation to reproduction is favored because warming induces faster somatic growth of small individuals and increased fecundity but reduced growth and higher mortality of larger individuals. Reduced optimum allocation to growth leads to further reductions in body size and an increasingly truncated population size structure with warming. Our study demonstrates how, by incorporating general physiological mechanisms driving the temperature dependence of life-history traits, the DEB-IPM framework is useful for investigating the adaptation of size-structured organisms to warming.


Subject(s)
Fertility , Reproduction , Animals , Reproduction/physiology , Temperature , Hot Temperature , Population Growth
11.
Biota Neotrop. (Online, Ed. ingl.) ; 23(2): e20231467, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1447507

ABSTRACT

Abstract This work was carried out in order to provide the length-weight relationship (LWR) and the allometric condition factor (Ka), as well as its correlation with limnological variables, for Prochilodus lineatus from the middle Tietê River basin. Fish were collected using gill nets in two rivers with contrasting environmental conditions, totaling 46 specimens in the highly polluted Tietê River, and 37 in the Peixe River, a relatively well-conserved tributary. Environmental measures were obtained concomitantly to the fish capture. The results showed an isometric growth (b = 3.00) for the fish from Tietê River and a positive allometric growth (b = 3.23) for the fish from Peixe River. The mean value of Ka was unexpectedly higher for the main river (Ka = 2.63) when compared to its tributary (Ka = 2.42), being statistically different from each other. This can be explained by the much higher availability of organic sediments in the main river, resulting from a long-term eutrophication process. Nevertheless, the positive and statistically significant correlations with dissolved oxygen, for both rivers, as well as significant negative correlations with electric conductivity, nitrogen and chlorophyll a for Tietê River, indicate the negative effects of the water quality deterioration on the fish condition factor. The work contributes to the expansion of knowledge about P. lineatus, the most important commercial fish of the middle Tietê River basin, which is severely impacted by unsustainable human actions.


Resumo Este trabalho foi realizado com o objetivo de fornecer a relação peso-comprimento (LWR) e o fator de condição alométrico (Ka), bem como sua correlação com variáveis limnológicas, para Prochilodus lineatus da bacia do médio rio Tietê. Os peixes foram coletados com redes de espera em dois rios com condições ambientais contrastantes, totalizando 46 espécimes no altamente poluído rio Tietê, e 37 no rio do Peixe, um tributário relativamente bem conservado. Medidas ambientais foram obtidas concomitantemente à captura dos peixes. Os resultados mostraram um crescimento isométrico (b = 3,00) para os peixes do rio Tietê e um crescimento alométrico positivo (b = 3,23) para os peixes do rio do Peixe. O valor médio de Ka foi, inesperadamente, maior para o rio principal (Ka = 2,63) quando comparado ao seu afluente (Ka = 2,42), sendo estatisticamente diferentes entre si. Isso pode ser explicado pela disponibilidade muito maior de sedimentos orgânicos no rio principal, resultante de um longo processo de eutrofização. No entanto, as correlações positivas e estatisticamente significativas com o oxigênio dissolvido, para ambos os rios, bem como correlações significativas negativas com a condutividade elétrica, nitrogênio e clorofila a para o rio Tietê, indicam os efeitos negativos da deterioração da qualidade da água sobre o fator condição dos peixes. O trabalho contribui para a expansão do conhecimento sobre P. lineatus, o peixe de maior importância comercial da bacia do médio rio Tietê, severamente impactada por ações humanas não-sustentáveis.

12.
Nutrients ; 14(9)2022 Apr 30.
Article in English | MEDLINE | ID: mdl-35565856

ABSTRACT

Background: The European Society for Clinical Nutrition and Metabolism database for chronic intestinal failure (CIF) was analyzed to investigate factors associated with nutritional status and the intravenous supplementation (IVS) dependency in children. Methods: Data collected: demographics, CIF mechanism, home parenteral nutrition program, z-scores of weight-for-age (WFA), length or height-for-age (LFA/HFA), and body mass index-for-age (BMI-FA). IVS dependency was calculated as the ratio of daily total IVS energy over estimated resting energy expenditure (%IVSE/REE). Results: Five hundred and fifty-eight patients were included, 57.2% of whom were male. CIF mechanisms at age 1−4 and 14−18 years, respectively: SBS 63.3%, 37.9%; dysmotility or mucosal disease: 36.7%, 62.1%. One-third had WFA and/or LFA/HFA z-scores < −2. One-third had %IVSE/REE > 125%. Multivariate analysis showed that mechanism of CIF was associated with WFA and/or LFA/HFA z-scores (negatively with mucosal disease) and %IVSE/REE (higher for dysmotility and lower in SBS with colon in continuity), while z-scores were negatively associated with %IVSE/REE. Conclusions: The main mechanism of CIF at young age was short bowel syndrome (SBS), whereas most patients facing adulthood had intestinal dysmotility or mucosal disease. One-third were underweight or stunted and had high IVS dependency. Considering that IVS dependency was associated with both CIF mechanisms and nutritional status, IVS dependency is suggested as a potential marker for CIF severity in children.


Subject(s)
Intestinal Diseases , Intestinal Failure , Parenteral Nutrition, Home , Short Bowel Syndrome , Adult , Child , Chronic Disease , Cross-Sectional Studies , Female , Humans , Intestinal Diseases/epidemiology , Intestinal Diseases/therapy , Male , Short Bowel Syndrome/therapy
13.
Matern Child Nutr ; 18(2): e13319, 2022 04.
Article in English | MEDLINE | ID: mdl-35043572

ABSTRACT

Compare with preterm formula, donor human milk (DM) is associated with a lower risk of mortality and morbidity in preterm infants. It is thus deemed superior to preterm formula as the sole diet or supplement to own mother's milk (OMM) for preterm infants, especially for those with very low birthweight (VLBW). This historic cohort study investigated the relationship between DM availability, and enteral feeding, body growth of VLBW infants by comparing two cohorts before and after the establishment of a human milk bank. A sub-analysis was also conducted between small-for-gestational-age (SGA) and non-SGA infants in our cohorts. Our results showed that DM availability was associated with earlier initiation and faster advancement of enteral feeding, earlier attainment of full enteral feeding, and a higher proportion of OMM in enteral feeding. DM availability was also associated with earlier regain of birthweight, but not with better body growth. SGA and non-SGA infants responded differently to DM availability with only the non-SGA group showing improved enteral feeding associated with DM availability. The poor growth of VLBW infants with fortified DM warrants further investigations on better fortification strategies to further improve body growth. Studies are also needed on long-term effects of DM feeding on the development of VLBW infants.


Subject(s)
Enteral Nutrition , Infant, Premature , Cohort Studies , Enteral Nutrition/methods , Humans , Infant , Infant Formula , Infant, Newborn , Infant, Very Low Birth Weight , Milk, Human
14.
Glob Chang Biol ; 28(7): 2259-2271, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35060649

ABSTRACT

According to the temperature-size rule, warming of aquatic ecosystems is generally predicted to increase individual growth rates but reduce asymptotic body sizes of ectotherms. However, we lack a comprehensive understanding of how growth and key processes affecting it, such as consumption and metabolism, depend on both temperature and body mass within species. This limits our ability to inform growth models, link experimental data to observed growth patterns, and advance mechanistic food web models. To examine the combined effects of body size and temperature on individual growth, as well as the link between maximum consumption, metabolism, and body growth, we conducted a systematic review and compiled experimental data on fishes from 52 studies that combined body mass and temperature treatments. By fitting hierarchical models accounting for variation between species, we estimated how maximum consumption and metabolic rate scale jointly with temperature and body mass within species. We found that whole-organism maximum consumption increases more slowly with body mass than metabolism, and is unimodal over the full temperature range, which leads to the prediction that optimum growth temperatures decline with body size. Using an independent dataset, we confirmed this negative relationship between optimum growth temperature and body size. Small individuals of a given population may, therefore, exhibit increased growth with initial warming, whereas larger conspecifics could be the first to experience negative impacts of warming on growth. These findings help advance mechanistic models of individual growth and food web dynamics and improve our understanding of how climate warming affects the growth and size structure of aquatic ectotherms.


Subject(s)
Ecosystem , Fishes , Animals , Body Size , Food Chain , Temperature
15.
Genes Cells ; 27(2): 145-151, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34918430

ABSTRACT

Limited oxygen availability impairs normal body growth, although the underlying mechanisms are not fully understood. In Drosophila, hypoxic responses in the larval fat body (FB) disturb the secretion of insulin-like peptides from the brain, inhibiting body growth. However, the cell-autonomous effects of hypoxia on the insulin-signaling pathway in larval FB have been underexplored. In this study, we aimed to examine the effects of overexpression of Sima, a Drosophila hypoxia-inducible factor-1 (HIF-1) α homolog and a key component of HIF-1 transcription factor essential for hypoxic adaptation, on the insulin-signaling pathway in larval FB. Forced expression of Sima in FB reduced the larval body growth with reduced Akt phosphorylation levels in FB cells and increased hemolymph sugar levels. Sima-mediated growth inhibition was reversed by overexpression of TOR or suppression of FOXO. After Sima overexpression, larvae showed higher expression levels of Tribbles, a negative regulator of Akt activity, and a simultaneous knockdown of Tribbles completely abolished the effects of Sima on larval body growth. Furthermore, a reporter analysis revealed Tribbles as a direct target gene of Sima. These results suggest that Sima in FB evokes Tribbles-mediated insulin resistance and consequently protects against aberrant insulin-dependent larval body growth under hypoxia.


Subject(s)
Cell Cycle Proteins , DNA-Binding Proteins , Drosophila Proteins , Drosophila , Protein Serine-Threonine Kinases , Animals , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Drosophila/genetics , Drosophila/growth & development , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Fat Body/metabolism , Gene Expression , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Larva/growth & development , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism
16.
Int J Mol Sci ; 22(23)2021 Dec 04.
Article in English | MEDLINE | ID: mdl-34884924

ABSTRACT

Endocrine-disrupting chemicals include natural and synthetic estrogens, such as 17α-ethynilestradiol (EE2), which can affect reproduction, growth and immunity. Estrogen signalling is mediated by nuclear or membrane estrogen receptors, such as the new G-protein-coupled estrogen receptor 1 (GPER1). The present work studies the effect of EE2 and G1 (an agonist of GPER1) on body and muscle parameters and growth-related genes of 54 two-year-old seabreams. The fish were fed a diet containing EE2 (EE2 group) and G1 (G1 group) for 45 days and then a diet without EE2 or G1 for 122 days. An untreated control group was also studied. At 45 days, the shortest body length was observed in the G1 group, while 79 and 122 days after the cessation of treatments, the shortest body growth was observed in the EE2 group. Hypertrophy of white fibers was higher in the EE2 and G1 groups than it was in the control group, whereas the opposite was the case with respect to hyperplasia. Textural hardness showed a negative correlation with the size of white fibers. At the end of the experiment, all fish analyzed in the EE2 group showed a predominance of the gonadal ovarian area. In addition, the highest expression of the mafbx gene (upregulated in catabolic signals) and mstn2 (myogenesis negative regulator) was found in EE2-exposed fish.


Subject(s)
Ethinyl Estradiol/pharmacology , Fish Proteins/genetics , Muscle, Skeletal/drug effects , Sea Bream/physiology , Animals , Aquaculture , Fish Proteins/agonists , Gene Expression/drug effects , Male , Muscle, Skeletal/physiology , Receptors, Estrogen/genetics , Receptors, G-Protein-Coupled/genetics , Sea Bream/genetics , Sea Bream/growth & development , Testis/drug effects
17.
Ecol Evol ; 11(21): 14789-14804, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34765141

ABSTRACT

Despite their importance in shaping life history tactics and population dynamics, individual growth trajectories have only been rarely explored in the wild because their analysis requires multiple measurements of individuals throughout their lifetime and some knowledge of age, a key timer of body growth. The availability of long-term longitudinal studies of two wild boar populations subjected to contrasting environments (rich vs. poor) provided an opportunity to analyze individual growth trajectories. We quantified wild boar growth trajectories at both the population and the individual levels using standard growth models (i.e., Gompertz, logistic, and monomolecular models) that encompass the expected range of growth shapes in determinate growers. Wild boar is a rather altricial species, with a polygynous mating system and is strongly sexually dimorphic in size. According to current theories of life history evolution, we thus expect wild boar to display a sex-specific Gompertz type growth trajectory and lower sexual size dimorphism in the poorer environment. While wild boar displayed the expected Gompertz type trajectory in the rich site at the population level, we found some evidence for potential differences in growth shapes between populations and individuals. Asymptotic body mass, growth rate and timing of maximum growth rate differed as well, which indicates a high flexibility of growth in wild boar. We also found a cohort effect on asymptotic body mass, which suggests that environmental conditions early in life shape body mass at adulthood in this species. Our findings demonstrate that body growth trajectories in wild boar are highly diverse in relation to differences of environmental context, sex and year of birth. Whether the intermediate ranking of wild boar along the precocial-altricial continuum of development at birth may explain the ability of this species to exhibit this high diversity of growth patterns remains to be investigated.

18.
Ecotoxicol Environ Saf ; 228: 113001, 2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34800778

ABSTRACT

Plastic debris has been found to be ubiquitous in many aquatic ecosystems and is constantly accumulating, not only because more and more plastic is being rapidly released into the environment, but also because its slow degradation means it persists in the water. Some more buoyant plastics accumulate in the water column, whereas other heavier types sink to the bottom. Consequently, the presence of microplastics can threaten organisms living in the water column as well as those found in the benthic zone. In this study, the filter feeder Daphnia has been found to ingest microplastics as the particle diameter (< 30 µm) is within their edible particle size range and they are unable to differentiate between particles of different natures. Four different treatments were considered: food only; only microplastic particles; 50% food and 50% microplastic particles; neither food nor microplastics. Sinking microplastics have been found to decrease Daphnia magna individuals' swimming velocity during vertical or cruising swimming trajectories, therefore demonstrating the sublethal effects microplastics have on this organism. In addition, microplastics decreased their body growth and survival rates. In cases with the presence of only microplastics, the swimming trajectories of Daphnia indicated the most serious stress experienced as individuals reversed vertical or cruising swimming trajectories to hopping and sinking movements. Therefore, Daphnia individuals in freshwater systems polluted by microplastics might take on the role of ingesting them and later on transporting them to deeper layer water column. In this way microplastics that would remain in the water column for a long time due to their buoyancy, might accumulate at the bottom of the water column.

19.
J Neuroendocrinol ; 33(11): e13025, 2021 11.
Article in English | MEDLINE | ID: mdl-34427011

ABSTRACT

Based on studies delivering ghrelin or ghrelin receptor agonists, we have learned a great deal about the importance of the brain ghrelin signalling system for a wide range of physiological processes that include feeding behaviours, growth hormone secretion and glucose homeostasis. Because these processes can be considered as essential to life, the question arises as to why mouse models of depleted ghrelin signalling are not all skinny dwarfs with a host of behavioural and metabolic problems. Here, we provide a systematic detailed review of the phenotype of mice with deficient ghrelin signalling to help better understand the relevance and importance of the brain ghrelin signalling system, with a particular emphasis on those questions that remain unanswered.


Subject(s)
Ghrelin , Receptors, Ghrelin , Animals , Disease Models, Animal , Feeding Behavior/physiology , Ghrelin/metabolism , Mice , Receptors, Ghrelin/genetics , Skeleton/metabolism
20.
Spine Deform ; 9(6): 1699-1703, 2021 11.
Article in English | MEDLINE | ID: mdl-34152579

ABSTRACT

PURPOSE: To report a case of iatrogenic durotomy with symptomatic Chiari-like deformity in a patient after undergoing anterior vertebral body growth modulation (AVBGM) in skeletally immature patients with adolescent idiopathic scoliosis (AIS). There have not been reports of iatrogenic durotomy in the literature and its management after AVBGM. METHODS: A 13-year-old skeletally immature girl underwent successful AVBGM for thoracic AIS from T6 to T12. Despite uneventful post-operative hospitalization, the patient suffered from recurrent and persistent bouts of headaches that were mostly orthostatic. At 3 months post-op, an MRI was performed on the suspicion of a cerebrospinal fluid (CSF) leak due to an iatrogenic durotomy. On MRI, decreased volume of CSF and a decrease in the dural sac diameter were observed. Furthermore, a pseudo-meningocele was seen at the last level of instrumentation. RESULTS: After an unsuccessfully trial of epidural blood patch combined with 5 days of supine immobilization, the patient was consented to screw revision as well as a lumbar drain. The lumbar drain was installed to redirect the CSF leak to allow the durotomy to heal. After 11 days, the drain was removed based on the favorable clinical evolution. CONCLUSION: Iatrogenic durotomy is a rare complication in AVBGM. This is the first report of such a case that involves a Chiari-like deformity on initial MRI investigation. We suggest that an MRI is performed for all patients presenting with symptoms of CSF leak after AVBGM.


Subject(s)
Kyphosis , Scoliosis , Adolescent , Female , Humans , Iatrogenic Disease , Lumbar Vertebrae , Lumbosacral Region , Scoliosis/surgery
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