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1.
Eur J Obstet Gynecol Reprod Biol ; 296: 83-90, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38417279

RESUMO

The rate of caesarean section (CS) is increasing worldwide. Defects in uterine healing have a major gynaecological and obstetric impact (uterine rupture, caesarean scar defect, caesarean scar pregnancy, placenta accreta spectrum). The complex process of cellular uterine healing after surgery, and specifically after CS, remains poorly understood in contrast to skin wound healing. This literature review on uterine wound healing was mainly based on histological observations, particularly after CS. The primary objective of the review was to examine the effects of CS on uterine tissue at the cellular level, based on histological observations. The secondary objectives were to describe the biomechanical characteristics and the therapies used to improve scar tissue after CS. This review was performed using PRISMA criteria, and PubMed was the data source. The study included all clinical and animal model studies with CS and histological analysis of the uterine scar area (macroscopic, microscopic, immunohistochemical and biomechanical). Twenty studies were included: 10 human and 10 animal models. In total, 533 female humans and 511 female animals were included. Review articles, meeting abstracts, case series, case reports, and abstracts without access to full-text were excluded. The search was limited to studies published in English. No correlation was found between cutaneous and uterine healing. The histology of uterine scars is characterized by disorganized smooth muscle, fibrosis with collagen fibres and fewer endometrial glands. As for skin healing, the initial inflammation phase and mediation of some growth factors (particularly connective tissue growth factor, vascular endothelial growth factor, platelet-derived growth factor, tumour necrosis factor α and tumour necrosis factor ß) seem to be essential. This initial phase has an impact on the subsequent phases of proliferation and maturation. Collagen appears to play a key role in the initial granulation tissue to replace the loss of substance. Subsequent maturation of the scar tissue is essential, with a decrease in collagen and smooth muscle restoration. Unlike skin, the glandular structure of uterine tissue could be responsible for the relatively high incidence of healing defects. Uterine scar defects after CS are characterized by an atrophic disorganized endometrium with atypia and a fibroblastic highly collagenic stromal reaction. Concerning immunohistochemistry, one study found a decrease in tumour necrosis factor ß in uterine scar defects. No correlation was found between biomechanical characteristics (particularly uterine strength) and the presence of a collagenous scar after CS. Based on the findings of this review, an illustration of current understanding about uterine healing is provided. There is currently no validated prevention of caesarean scar defects. Various treatments to improve uterine healing after CS have been tested, and appeared to have good efficacy in animal studies: alpha lipoic acid, growth factors, collagen scaffolds and mesenchymal stem cells. Further prospective studies are needed.


Assuntos
Cesárea , Doenças Uterinas , Animais , Feminino , Gravidez , Humanos , Cesárea/efeitos adversos , Cicatriz/etiologia , Linfotoxina-alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular , Cicatrização , Doenças Uterinas/complicações , Colágeno
2.
Soc Sci Med ; 332: 116103, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37506485

RESUMO

Mandatory COVID-19 vaccination requirements for healthcare workers in the United States, instituted at the height of the pandemic to protect vulnerable patients and preserve the infrastructure of healthcare, nonetheless met with resistance by some members of the work force. As unprecedented numbers of employees sought religious accommodations, chaplain leaders were recruited by institutional leadership to adjudicate these requests, either alone or as part of a committee. This study reports results of a survey conducted from 6/1/2022 to 7/15/2022 with U.S. healthcare chaplains (n = 76) who were involved in the evaluation of coworker requests for religious exemption to the COVID-19 vaccine anytime during the pandemic until they accessed the survey. Chaplains were recruited online through national chaplaincy and ethics organizations. A mixed methods design facilitates integration of statistically significant associations with chaplains' in-depth reflections on their experience. Surveying the religious experts on the review committee affords a rare look into how the tension between the free exercise of religion in the workplace and the obligation to protect the public played out during the pandemic. The study further addresses a gap in research literature on the experience of chaplains during the pandemic and identifies unique features of moral injury experienced by a subset of healthcare providers. Chaplains largely perceived their involvement as promoting an ethical, informed process of review. Although all chaplains found this role stressful, high levels of meaning were protective against distress. Sources of distress identified included: ethical concern that granting exemptions would lead to the spread of the virus; inconsistencies in the review process; and, repeated exposure to coworkers' misunderstanding and political use of religious teachings. Featuring prominently in comments from chaplains was the difficulty navigating requests in the context of anti-science, anti-vaccine, and politically charged public discourse.

3.
J Visc Surg ; 160(1): 52-54, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36270954

RESUMO

Pressurized intraperitoneal aerosol chemotherapy, named PIPAC, is now used in many centers around the world and as an intraperitoneal drug delivery system for treatment of peritoneal carcinomatosis. Recently, many of us have encountered problems during PIPAC procedures due to changes in material and production features of the original PIPAC nebulizer. Concomitantly, new PIPAC nebulizers proposed by other manufacturers are being launched on the market; which claim that they are the same as the original device in delivering PIPAC. However, these new devices are all different in terms of materials, technical characteristics and costs. We have considered that, to maintain the acquired results of PIPAC, we must ensure that the new systems are equivalent. The characteristics deemed essential by the expert group are as follows: 1: The nebulizer must be able to create droplets through an injector pressure between 10 and 20 bars, 2: The mean droplet size must be 3 micrometers, with 95% of the droplets between 0 and 10 micrometers, 3: The diffusion angle must be 70 degrees, which is the minimum.


Assuntos
Neoplasias Peritoneais , Humanos , Aerossóis/uso terapêutico , Neoplasias Peritoneais/tratamento farmacológico , Nebulizadores e Vaporizadores
4.
Theriogenology ; 187: 135-140, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35569412

RESUMO

OBJECTIVES: The main aim of the study was to quantitatively characterize placental perfusion using contrast-enhanced ultrasound in a longitudinal study performed in pregnant rabbits. As a secondary objective, we qualitatively assessed the placental perfusion. METHODS: Three pregnant rabbits were used. Contrast-enhanced ultrasound was performed twice for each dam, either on embryo development (ED) day 14, 21 or 28 of pregnancy, under general anesthesia. Both qualitative and quantitative analyses were performed based on ultrasound assessment. RESULTS: Altogether, data from 29 fetuses were analyzed: 10 at ED-14; 12 at ED-21, and 7 at ED-28. Placental vascularization was mainly peripheral at the earliest gestational age and became gradually homogeneous within the whole placenta as pregnancy progressed. Intensity parameters and relative blood flows significantly increased with gestational age. The wash-in and wash-out rates were correlated and a significant increase in wash-in compared to in wash-out rates was observed with increased gestational age. CONCLUSION: Contrast-enhanced ultrasound is feasible in animal models and allows qualitative and quantitative analysis of placental vascularization during pregnancy.


Assuntos
Placenta , Animais , Feminino , Idade Gestacional , Estudos Longitudinais , Perfusão/veterinária , Placenta/diagnóstico por imagem , Gravidez , Coelhos , Ultrassonografia/veterinária
5.
Animal ; 16(4): 100498, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35338904

RESUMO

Research about mare's milk is mainly focused on quality and information about quantity is incomplete partly due to the lack of a consensus on the method of measuring milk yield. The live weight, body condition at foaling and age of mares are factors influencing milk yield. The influence of mare parity, however, remains unclear. Over a period of 2 years (2018-2019), milk yield was evaluated on 65 mares (51 multiparous and 13 primiparous). Mares and foals were kept in a group at pasture. One method of milk yield measurement and one proxy method were applied; milking and weight-suckle-weight (WSW), respectively. The procedure was performed at five timepoints during the lactation period (3-30-60-90 and 180 days) without repetition. The relevance of WSW was addressed by studying the correlation between the two methods on 23 individuals. Factors influencing milk yield, through milking data, were studied on 57 individuals. Data was divided into two subsets. The first was an explanatory matrix containing the live weight of mares 24 h after parturition, parity, age, year of lactation and foal gender. The second was a response matrix containing data from milking at the five timepoints of the lactation. A correlation was found (RV = 0.41) between milking and WSW at day 3, however no correlation was found for other timepoints (RV ≤ 0.15). The live weight of the mare 24 h after foaling, age and parity appeared to have a significant impact on milk production (P < 0.05). Thus, older or multiparous mares showed a higher milk yield than younger or primiparous mares. In addition, mares with a higher live weight after foaling produced more milk than those with a lower live weight. Overall, results can lead us to two main conclusions. First, the WSW method performed at five different timepoints of the lactation, but without repeated measurements, is not an efficient way to estimate the milk yield of mares. Secondly, results concerning the live weight and age of mares were in accordance with previous studies. The influence of parity was also highlighted, confirming trends showed by other authors. Age and parity are closely related in our population, making it difficult to differentially assess their effects. Being able to identify the impact of both factors independently would benefit several sectors of the horse industry from sport to mare milk producers.


Assuntos
Lactação , Leite , Animais , Feminino , Cavalos , Lactação/fisiologia , Paridade , Parto , Gravidez
6.
Domest Anim Endocrinol ; 79: 106692, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34823139

RESUMO

Horses have been domesticated by man and historical information mostly associates horses with men. Nowadays, however, horse riding is essentially by women. Women are also very much involved in equine sciences, with a large contribution to the understanding of fetoplacental development. While highlighting the work of female scientists, this review describes the recent advances in equine fetoplacental studies, focusing on data obtained by new generation sequencing and progress on the understanding of the role of placental progesterone metabolites throughout gestation. A second emphasis is made on fetal programming, a currently very active field, where the importance of maternal nutrition, mare management or the use of embryo technologies has been shown to induce long term effects in the offspring that might affect progeny's performance. Finally, new perspectives for the study of equine pregnancy are drawn, that will rely on new methodologies applied to molecular explorations and imaging.


Assuntos
Placenta , Placentação , Animais , Feminino , Desenvolvimento Fetal , Cavalos , Humanos , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Progesterona
9.
Sci Total Environ ; 742: 140524, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32619842

RESUMO

Improving the food supply chain efficiency has been identified as an essential means to enhance food security, while reducing pressure on natural resources. Adequate food loss and waste (FLW) management has been proposed as an approach to meet these objectives. The main hypothesis of this study is to consider that the "strong fluctuations and short-term changes" on eating habits may have major consequences on potential FLW generation and management, as well as on GHG emissions, all taking into account the nutritional and the economic cost. Due to the exceptional lockdown measures imposed by the Spanish government, as a consequence of the emerging coronavirus disease, COVID-19, food production and consumption systems have undergone significant changes, which must be properly studied in order to propose strategies from the lessons learned. Taking Spain as a case study, the methodological approach included a deep analysis of the inputs and outputs of the Spanish food basket, the supply chain by means of a Material Flow Analysis, as well as an economic and comprehensive nutritional assessment, all under a life cycle thinking approach. The results reveal that during the first weeks of the COVID-19 lockdown, there was no significant adjustment in overall FLW generation, but a partial reallocation from extra-domestic consumption to households occurred (12% increase in household FLW). Moreover, the economic impact (+11%), GHG emissions (+10%), and the nutritional content (-8%) complete the multivariable impact profile that the COVID-19 outbreak had on FLW generation and management. Accordingly, this study once again highlights that measures aimed at reducing FLW, particularly in the household sector, are critical to make better use of food surpluses and FLW prevention and control, allowing us to confront future unforeseen scenarios.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Eliminação de Resíduos , Gerenciamento de Resíduos , Betacoronavirus , COVID-19 , Surtos de Doenças , Alimentos , Humanos , SARS-CoV-2 , Espanha
10.
Sci Total Environ ; 721: 137744, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32169649

RESUMO

Food and beverage packaging represent a relevant fraction of municipal solid waste, and its adequate management is critical. Selective waste collection by an authorized organization according to an Extended Producer Responsibility System (EPRS) is the current option implemented in Spain for packaging. Other European countries have selected an alternative or a complement: a Deposit-Refund System (DRS) for certain type of beverage packaging. The selection of an EPRS or a DRS is a complex task and this work developed a universal methodology for the evaluation of optimal waste packaging management systems, focused on food and beverage. Life Cycle Assessment (LCA) approach was applied to compare the current EPRS vs the implementation of a new system, with the coexistence of a DRS and a reduced EPRS. Although the environmental savings of the new system are superior to its impacts, even if the DRS would reach a value of 90% for the package return index, the current EPRS obtains significantly better environmental results. All impact categories are favorable to the current EPRS, except ADP, where the potentially higher DRS recycling rate is manifested. The impact associated to the flow of specific DRS packages in the new system is clearly higher than that linked to the flow of DRS excluded packages and it is even higher that the impact of the total joint flow in the current EPRS for all categories except ADP. The fundamental cause of this high impact is the backhauling stage to transport the recovered packages to the counting plants without compacting. A sensitivity analysis confirmed the robustness of the preference of the current EPRS over the combination of a DRS and a reduced EPRS. The developed approach supposes a methodological advance that can be extended to previously realized studies about the implementation of waste management systems in other contexts.

11.
Sci Total Environ ; 702: 134603, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726337

RESUMO

One-way packaging can represent up to half the environmental impacts of the food value chain and thus optimising its management is essential. Collective selective waste collection managed by authorised organisations (Extended Producer Responsibility, EPR), with or without Deposit-Refund Systems (DRS) are alternatives implemented at European level to handle this problem. Since there is no single simple formula that can be applied to every waste management system, this case study is focused on the entire Spanish model of one-way food packaging waste management, from collection of each fraction in specific containers to final treatment, considering eight different materials. For the analysis, six different impact categories were considered: abiotic depletion potential, global warming potential, acidification potential, eutrophication potential, ozone depletion potential and photochemical ozone formation. Results reveal that the recycling stage is the main stage contributing to the environmental impacts, but the environmental savings related to the recovery of materials in this stage compensates these loads and the system must be considered advantageous for the environment. By contrast, sorting plants present the lowest contributions and is the least significant stage. Significant environmental improvements (close to 10%) would be achieved by addressing the total bulk collection flow to mechanical-biological treatment and increasing the selective collection of light and glass packaging waste. This study can serve to identify common drivers that contribute significantly to the development of an integrated approach to waste packaging management and as baseline for comparison studies with alternative waste recovery technologies and systems.

12.
Waste Manag ; 96: 57-64, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376970

RESUMO

The aviation industry generates a significant amount of comingle waste. Nowadays, companies are making efforts to enhance waste management and reduce waste generation. In order to improve present practices and implement a proper waste management system, the quantities, materials, and typology of waste generated need to be studied. A total of 145 airplanes were analysed. We differentiated 5 strips of duration and identified 4 different generation sources within the cabin associated to the business and tourist passenger classes. We classified and characterized the waste into 20 different materials. Results provide a detailed, representative and adapted study of the catering waste generated in the aviation industry. The characterization, which allows distinguishing between manipulated and unmanipulated materials, aims at providing useful information to reduce the generation of waste. The analysis performed in the present study shows that the flying distance increases the waste generation, as more food is served. It also shows that organic matter, paper/cardboard and packaging are the dominant materials in the waste generated in flights. The results of the characterizations obtained allow making some recommendations. The use of bi-compartmentalized waste trolleys to separate on-board recyclable materials from the rest is desirable to obtain a clean recoverable waste stream. Supressing unpopular food from menus, identified analysing the leftovers, could also reduce the amount of waste generated. (This characterization study is part of the European project LIFE + Zero Cabin Waste.). Changes in the CE 1069/2009 regulation would allow more waste to be recycled instead of landfilled. Ultimately, the information obtained from this study will be used to design a more sustainable waste management system.


Assuntos
Gerenciamento de Resíduos , Aeronaves , Alimentos , Embalagem de Produtos , Reciclagem
13.
Animal ; 12(s2): s363-s371, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30139395

RESUMO

Epidemiological studies in humans and animal models (including ruminants and horses) have highlighted the critical role of nutrition on developmental programming. Indeed, it has been demonstrated that the nutritional environment during the periconceptional period and foetal development can altered the postnatal performance of the resultant offspring. This nutritional programming can be exerted by maternal and paternal lineages and can affect offspring beyond the F1 generation. Alterations in epigenetic mechanisms have been proposed as the causative link behind the programming trajectories observed in the offspring. Although a clear cause-effect relationship between epigenetic modifications during early development and later offspring phenotype has not been demonstrated in livestock species, strong associations have been reported for some epigenetic marks (e.g. messenger RNA) that are worth exploring as possible predictors of future offspring phenotype. In this review, we shortly describe the main epigenetic mechanisms studied so far in mammals (i.e. mainly in the mouse) thought to be associated with developmental programming, and discuss the few studies available in mammalian herbivores (e.g. cattle) showing the effect of nutrition on epigenetic marks and the associated phenotype. Clearly, there is a need to develop research on nutritional strategies capable of modulating the epigenetic machinery with positive influence on the phenotype of livestock herbivores. This type of research is needed to alleviate the challenges currently faced by the livestock industry (e.g. impaired fertility of high-yielding dairy cows). This in turn will have a positive influence on animal welfare and productivity of livestock enterprises.


Assuntos
Epigênese Genética , Mamíferos/genética , Estado Nutricional , Animais , Bovinos , Feminino , Desenvolvimento Fetal , Herbivoria , Gado , Mamíferos/embriologia , Mamíferos/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Fenótipo , Gravidez , Ruminantes
14.
J Dev Orig Health Dis ; 9(5): 519-529, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29909796

RESUMO

The aim of the present work was to address experimentally the possible impact of exposure to air pollution during gestation on the differentiation and function of the gonads of the offspring using a rabbit model. Rabbits were exposed daily to diluted diesel exhaust gas or filtered air from the 3rd until the 27th day of gestation, during which time germ cells migrate in genital ridges and divide, and fetal sex is determined. Offspring gonads were collected shortly before birth (28th day of gestation) or after puberty (7.5 months after birth). The structure of the gonads was analyzed by histological and immunohistological methods. Serum concentrations of testosterone and anti-Müllerian hormone were determined using ELISA. The morphology and the endocrine function of the gonads collected just at the arrest of the exposure were similar in polluted and control animals in both sexes. No differences were observed as well in gonads collected after puberty. Sperm was collected at the head of the epididymis in adults. Sperm motility and DNA fragmentation were measured. Among all parameters analyzed, only the sperm DNA fragmentation rate was increased three-fold in exposed males. Mechanisms responsible for these modifications and their physiological consequences are to be further clarified.


Assuntos
Desenvolvimento Fetal/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Emissões de Veículos/toxicidade , Animais , Hormônio Antimülleriano/sangue , Fragmentação do DNA/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Gônadas/embriologia , Gônadas/patologia , Masculino , Ovário/efeitos dos fármacos , Ovário/patologia , Gravidez , Coelhos , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia , Testosterona/sangue
15.
Placenta ; 64: 44-52, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29626980

RESUMO

INTRODUCTION: Feeding pregnant broodmares with cereal concentrates has been shown to increase maternal insulin resistance and affect foal metabolism in the short and long-term. These effects are likely to be mediated by the placenta. Here, we investigated feto-placental biometry and placental structure and function at term in mares fed with or without cereals concentrates. MATERIAL AND METHODS: From 7 months of gestation, 22 multiparous mares were fed forage only (group F (n = 12)) or received forage and cracked barley (group B (n = 10)) until foaling. Foals and placentas were weighed and placental samples were collected above the umbilical cord insertion at birth. Placental histological structure was studied by stereology. A RNAseq analysis was performed on 9 placentas of each group. Enrichment of gene sets was analysed using the Gene Set Enrichment Analysis (GSEA) software using the KEGG and GO databases. RESULTS: No difference in feto-placental biometry was observed between groups. The volume of microcotyledonary vessels was decreased in B placentas and the vascular wall of allantoic arterioles was thickened. Gene sets involved in neutral amino acids, folate and anions transport and fatty acids, cholesterol and folate degradation were down-regulated while gene sets involved in RNA expression, inflammation and vascularisation were up-regulated in B placentas. CONCLUSION: Feeding pregnant mares with concentrates from mid-gestation alters the placental function and structure as observed in other species in cases of maternal insulin resistance.


Assuntos
Grão Comestível/efeitos adversos , Resistência à Insulina , Placenta/patologia , Complicações na Gravidez/etiologia , Transcriptoma , Animais , Biometria , Feminino , Cavalos , Placenta/metabolismo , Gravidez , Complicações na Gravidez/metabolismo , Complicações na Gravidez/patologia
16.
PLoS One ; 13(1): e0190309, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29373573

RESUMO

INTRODUCTION: Obesity is a growing concern in horses. The effects of maternal obesity on maternal metabolism and low-grade inflammation during pregnancy, as well as offspring growth, metabolism, low-grade inflammation, testicular maturation and osteochondrotic lesions until 18 months of age were investigated. MATERIAL AND METHODS: Twenty-four mares were used and separated into two groups at insemination according to body condition score (BCS): Normal (N, n = 10, BCS ≤4) and Obese (O, n = 14, BCS ≥4.25). BCS and plasma glucose, insulin, triglyceride, urea, non-esterified fatty acid, serum amyloid A (SAA), leptin and adiponectin concentrations were monitored throughout gestation. At 300 days of gestation, a Frequently Sampled Intravenous Glucose Tolerance Test (FSIGT) was performed. After parturition, foals' weight and size were monitored until 18 months of age with plasma SAA, leptin, adiponectin, triiodothyronine (T3), thyroxine (T4) and cortisol concentrations measured at regular intervals. At 6, 12 and 18 months of age, FSIGT and osteoarticular examinations were performed. Males were gelded at one year and expression of genes involved in testicular maturation analysed by RT-qPCR. RESULTS: Throughout the experiment, maternal BCS was higher in O versus N mares. During gestation, plasma urea and adiponectin were decreased and SAA and leptin increased in O versus N mares. O mares were also more insulin resistant than N mares with a higher glucose effectiveness. Postnatally, there was no difference in offspring growth between groups. Nevertheless, plasma SAA concentrations were increased in O versus N foals until 6 months, with O foals being consistently more insulin resistant with a higher glucose effectiveness. At 12 months of age, O foals were significantly more affected by osteochondrosis than N foals. All other parameters were not different between groups. CONCLUSION: In conclusion, maternal obesity altered metabolism and increased low-grade inflammation in both dams and foals. The risk of developing osteochondrosis at 12 months of age was also higher in foals born to obese dams.


Assuntos
Doenças dos Cavalos/patologia , Doenças dos Cavalos/fisiopatologia , Inflamação/veterinária , Resistência à Insulina/fisiologia , Obesidade/veterinária , Osteocondrose/veterinária , Complicações na Gravidez/veterinária , Adiponectina/sangue , Animais , Animais Recém-Nascidos , Glicemia/metabolismo , Feminino , Teste de Tolerância a Glucose , Cavalos , Inflamação/etiologia , Insulina/sangue , Leptina/sangue , Masculino , Troca Materno-Fetal , Obesidade/complicações , Obesidade/fisiopatologia , Osteocondrose/etiologia , Gravidez , Complicações na Gravidez/patologia , Complicações na Gravidez/fisiopatologia
17.
Theriogenology ; 108: 321-330, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29288976

RESUMO

Primiparous mares are known to produce smaller foals than multiparous mares. This difference seems to be partly explained by the reduced exchange surface and volume of the placental villi in primiparous compared to multiparous placentas. The effect of maternal parity on foals' post-natal growth, metabolism and sexual maturation, however, has been given little consideration. The objectives of this work were to analyse placental biometry and structure at term, growth of foals and yearlings, their metabolism and testicular maturation at one year of age. Twenty multiparous mares (M), aged over 6 years and 12 primiparous mares (P), aged up to 5 years were artificially inseminated with the same stallion and monitored the same way until foaling. At birth, foals and placentas were measured and placentas were sampled above at the umbilical cord insertion, as well as in the pregnant and the non-pregnant horn to perform stereological analyses. Foals were weighed and measured until 540 days of age. At 120 and 360 days of age, an Intravenous Glucose Tolerance Test was performed on foals and yearlings. At 360 days of age, the males were castrated and testicular maturation analysed by RT-qPCR. At birth, P dams produced lighter and smaller foals and placentas. The foal birth weight to placental surface ratio was lower in the P compared to the M group. P Foals remained lighter than M foals until 360 days of age and smaller until at least 540 days of age. At 120 days of age, P foals had a higher glucose tolerance than M foals, and then may be less mature than M foals in terms of the control of their glucose homeostasis. At 360 days of age, the testicles of prepubertal P stallions were less mature in the P vs the M group. In conclusion, primiparous dams produce intrauterine growth restricted, less mature and smaller foals compared to multiparous dams with altered metabolism and growth until at least 540 days of age. These differences could affect the sport career of these foals, especially if it begins at an early age.


Assuntos
Cavalos/fisiologia , Paridade , Placenta/fisiologia , Placentação , Animais , Feminino , Teste de Tolerância a Glucose/veterinária , Cavalos/crescimento & desenvolvimento , Cavalos/metabolismo , Gravidez , Maturidade Sexual
18.
Equine Vet J ; 50(3): 405-414, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28963763

RESUMO

BACKGROUND: Following embryo transfer (ET), the size and breed of the recipient mare can affect fetal development and subsequent post natal growth rate and insulin sensitivity in foals. OBJECTIVES: To investigate placental adaptation in pregnancies where increased or restricted fetal growth was induced through ET between Pony, Saddlebred and Draught horses. STUDY DESIGN: In vivo experiment. METHODS: Control Pony (P, n = 21) and Saddlebred (S, n = 28) pregnancies were obtained by artificial insemination. Increased pregnancies were obtained by transferring Pony (P-D, n = 6) and Saddlebred (S-D, n = 8) embryos into Draught mares. Restricted pregnancies were obtained by transferring Saddlebred embryos into Pony mares (S-P, n = 6). Placental weight and surface were recorded and samples collected for stereology and analysis of expression of genes involved in placental growth, vascularisation and nutrient transport. Data were analysed by linear model. RESULTS: S-P foals were growth retarded when compared with controls despite increased gestational length. Placental weight was reduced but placental surface density and volume fraction were increased. Placental expression of genes involved in growth and development and nutrient transfer was strongly reduced. In contrast, placental size and weight were increased in enhanced growth P-D and S-D foals. The trophoblastic surface density and the allantoic vessels surface density were decreased in P-D and S-D, respectively, both with very few modifications in gene expression. MAIN LIMITATIONS: Control embryos were produced by artificial insemination whereas experimental embryos were produced by ET. CONCLUSIONS: Placental structure and gene expression are modified after ET into a smaller or larger breed than that of the embryo. These adaptations contribute to the observed phenotype of foal growth restriction or enhanced growth at birth.


Assuntos
Retardo do Crescimento Fetal/veterinária , Doenças dos Cavalos/patologia , Placenta/anormalidades , Animais , Animais Recém-Nascidos , Transferência Embrionária , Feminino , Desenvolvimento Fetal , Cavalos , Gravidez
19.
Theriogenology ; 108: 136-145, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29207294

RESUMO

Ponies and sometimes draft horses are often used as experimental models for horses although size and metabolic parameters are known to vary between horse breeds. So far, there is little information about differences of placental structure and no information about differences of placental function between breeds. The aim of this study was to investigate differences in placental size, structure and function at birth in relation to foal size and weight in ponies, Saddlebred and draft horses. Pony, Saddlebred and draft horse pregnancies were obtained by artificial insemination over 2 successive breeding seasons. Foals and total fetal membranes (TFM) were weighed and placentas measured for surface area at term. Placentas were sampled above the umbilical cord insertion. Surface density and volume fraction of the different cellular components of the placenta were measured on histological sections using stereology. The expression of genes involved in growth and development, nutrient transfer and vascularization was compared between groups. Foals and TFM were lighter at birth in ponies than Saddlebred horses, and both were lighter compared to draft horses. The surface density and volume fraction of microcotyledonary vessels was increased in pony compared to Saddlebred placentas. The relative expression of genes involved in growth and development was different between breeds and increased with maternal, fetal and placental weight. Primiparous dams produced lighter foals and smaller placentas, associated with a decreased volume fraction of microcotyledonary vessels and genes involved in growth and development and vascularization. Foal sex had little effect on placental structure and function as the expression of only one gene differed according to sex, with EGFR expression being decreased in placentas of females compared to males. In conclusion, foal and placental weight, as well as placental expression of genes involved in growth and development were correlated with maternal size. Placental structure also differed between breeds, with a stronger difference between ponies and both breeds of horses.


Assuntos
Cavalos/genética , Placenta/anatomia & histologia , Placenta/fisiologia , Prenhez , Animais , Animais Recém-Nascidos , Biometria , Peso ao Nascer , Tamanho Corporal , Feminino , Regulação da Expressão Gênica/fisiologia , Cavalos/anatomia & histologia , Cavalos/fisiologia , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Prenhez/genética , Prenhez/fisiologia
20.
Int J Obes (Lond) ; 41(5): 820-823, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28133361

RESUMO

Limited research has explored longitudinal impact of stress on negative health outcomes, including overweight and obesity in Asian societies. Using data from a longitudinal school-based health promotion study conducted in Wuhan, China from 1999 to 2004, this study investigated the longitudinal effects of childhood stress exposure, including stressors related to school, family, peers, violence and health on overweight, and obesity risk during the transition to adolescence among 2179 Chinese adolescents. Results showed that health stressors were consistently related to higher BMI Z score for both boys and girls baseline, it also predicted higher likelihood of overweight status over time for girls. This finding highlights a particularly challenging time period for girls, suggesting a particular challenging time they face at the intersection of puberty and demanding school environment.


Assuntos
Comportamento do Adolescente/psicologia , Imagem Corporal/psicologia , Comportamento Infantil/psicologia , Promoção da Saúde , Obesidade Pediátrica/psicologia , Estresse Psicológico/psicologia , Adolescente , Criança , China/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Obesidade Pediátrica/epidemiologia , Maturidade Sexual , Estresse Psicológico/epidemiologia , Urbanização
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