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1.
Hum Reprod ; 34(7): 1334-1344, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31241750

RESUMO

STUDY QUESTION: Does female weekly alcohol intake and binge drinking impact the chance of a successful fertility treatment? SUMMARY ANSWER: Low-to-moderate weekly alcohol drinking and binge drinking were not associated with the chance of achieving a clinical pregnancy or a live birth among women and couples undergoing medically assisted reproduction (MAR) treatments. WHAT IS KNOWN ALREADY: Alcohol consumption is common among women of reproductive age, even though health authorities advise women trying to conceive to abstain from drinking. A growing number of couples struggle with infertility, but it is unknown whether low-to-moderate levels of alcohol consumption and alcohol binge drinking impair success in fertility treatment. STUDY DESIGN, SIZE, DURATION: Cohort study with prospectively collected exposure information including 1708 women and potential partners undergoing fertility treatment at the public fertility clinic, Aarhus University Hospital, 1 January 2010 to 31 August 2015. In total, data on 1511 intrauterine insemination (IUI) cycles, 2870 in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles and 1355 frozen embryo transfer cycles. PARTTICIPANTS/MATERIALS, SETTING, METHODS: Exposure to weekly average alcohol intake was assessed from questionnaires completed by participants before the start of treatment. Outcome measures are the achievement of a clinical pregnancy and live birth in consecutive treatment cycles in the Danish national health registries, enabling complete follow-up. A modified Poisson regression with robust standard errors was used to evaluate associations between a weekly average alcohol intake and MAR outcomes, adjusting for female age, body mass index, cigarette smoking, coffee consumption, chronic diseases, level of education, and cycle number. When evaluating the association between binge drinking in the month prior to baseline and MAR outcomes the analyses were further adjusted for average weekly alcohol consumption. MAIN RESULTS AND THE ROLE OF CHANCE: Low-to-moderate average weekly alcohol intake was not statistically significantly associated with the chance of achieving a clinical pregnancy or a live birth following IUI or IVF/ICSI treatment cycles. Compared to women abstaining from alcohol, the adjusted relative risks for achieving a live birth among those reporting 1-2, 3-7, and >7 drinks per week were 1.00 (95% CI 0.66; 1.53), 1.20 (0.76; 1.91), and 1.48 (0.56; 3.93), respectively, among women initiating IUI treatments. Among those initiating IVF/ICSI treatments, the chance for achieving a live birth among those reporting 1-2, 3-7, and >7 drinks per week were 1.00 (0.83; 1.21), 0.95 (0.75; 1.20), and 0.89 (0.53; 1.51), respectively. The chance of achieving a live birth in the first IUI or IVF/ICSI treatment cycle was unrelated to the number of binge drinking episodes in the month preceding baseline. LIMITATIONS, REASONS FOR CAUTION: The risk of non-differential exposure misclassification, confounding, or chance cannot be ruled out. In addition, due to the low number of women reporting an intake of >7 drinks/week, the potential effect of high alcohol consumption should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS: Although it remains unsettled if and how alcohol affects female reproduction, our results indicate that is not necessary to abstain from alcohol when striving for a successful outcome following fertility treatment. STUDY FUNDING/COMPETING INTEREST(S): J.L. is supported by a fully financed Ph.D. scholarship from Aarhus University and has received funds from the A.P. Møller foundation. The funding sources had no involvement in the conduct of the article. Dr Kesmodel reports personal fees from MSD and Ferring Pharmaceuticals outside the submitted work. All other authors have no conflicts of interest to declare and all have completed the ICMJE disclosure form. TRIAL REGISTRATION NUMBER: Not relevant.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Coeficiente de Natalidade , Fertilização in vitro/estatística & dados numéricos , Inseminação Artificial/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Gravidez
2.
BJOG ; 126(2): 253-260, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30341984

RESUMO

OBJECTIVE: To assess the risk of stillbirth in low-risk in vitro fertilisation (IVF) pregnancies. DESIGN: Register-based national cohort study. SETTING: Denmark 2003-2013. POPULATION: Cohort of 425 732 singleton pregnancies including 10 235 conceived following IVF/intracytoplasmic sperm injection (ICSI), 4521 conceived following intrauterine insemination (IUI), and 410 976 spontaneously conceived. METHODS: Information on pregnancy, obstetrical risk factors, stillbirth, and fertility treatment was obtained from the Danish national health registers for all pregnancies after gestational week 21+6 . We estimated the overall and gestational age-specific risk of stillbirth in low-risk term pregnancies following IVF, ICSI, and IUI. Further, we estimated the association between stillbirth and IVF and ICSI respectively as well as fresh or frozen-thawed embryo transfer. MAIN OUTCOME MEASURES: Risk of stillbirth. RESULTS: The number of stillbirths in spontaneously conceived and IVF/ICSI low-risk term pregnancies was 525 (0.1%) and 35 (0.3%), respectively. In multivariate analysis, the risk of stillbirth in pregnancies following IVF/ICSI was increased (odds ratio 2.1, 95% CI 1.4-3.1). The risk of stillbirth was correspondingly increased in time-to-event analyses taking risk time for each fetus into account from gestational week 37 and onwards (hazard ratio 2.4, 95% CI 1.6-3.6). In sub-analyses, the risk of stillbirth was increased for pregnancies following ICSI (odds ratio 2.2, 95% CI 1.2-3.1), but not IVF (odds ratio 1.7, 95% CI 0.9-3.1). CONCLUSION: We found a systematically increased risk of stillbirth in low-risk term pregnancies following IVF/ICSI. Whether the risk was related to the treatment or to underlying subfertility is uncertain. The results may indicate a need for obstetrical surveillance for these pregnancies when reaching term. TWEETABLE ABSTRACT: Increased risk of stillbirth in low-risk term pregnancies following fresh cycle IVF/ICSI.


Assuntos
Injeções de Esperma Intracitoplásmicas/efeitos adversos , Natimorto/epidemiologia , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Dinamarca , Feminino , Fertilização in vitro/efeitos adversos , Fertilização in vitro/estatística & dados numéricos , Idade Gestacional , Humanos , Inseminação Artificial/efeitos adversos , Inseminação Artificial/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Gravidez , Sistema de Registros , Medição de Risco , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Nascimento a Termo
3.
BJOG ; 126(2): 158-166, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30168249

RESUMO

BACKGROUND: Assisted reproductive techniques are associated with an increased risk of adverse pregnancy outcomes, including low birthweight and intrauterine growth restriction. Yet, the long-term follow-up on the growth of these children is limited. OBJECTIVE: To systematically review the literature on post-neonatal height and weight among children conceived following in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment, compared with that of children born after spontaneous conception. SEARCH STRATEGY: A systematic computerised literature search using the online databases PubMed, Embase, and Scopus. SELECTION CRITERIA: Cohort or case-control studies with an exposed group of singletons conceived following IVF or ICSI along with a control group of spontaneously conceived singletons. DATA COLLECTION AND ANALYSIS: Studies were reviewed by at least two authors. Meta-analyses were conducted using Cochrane Review Manager. The quality of the studies was assessed with the Newcastle-Ottawa Scale. MAIN RESULTS: Twenty studies were included, with 13 of these eligible for meta-analyses. The meta-analyses compared 3972 children born after IVF/ICSI with 11 012 spontaneously conceived children and revealed no statistically significant difference in child weight [mean difference (MD) in weight of -160 g; 95% confidence interval (95% CI) -360, 3]. When stratifying by age of child at follow-up, we found a significant lower weight in children aged 0-4 years conceived following IVF/ICSI treatment (MD -180 g; 95% CI -320, -4), but this was no longer significant in children from 5 years of age (MD -160 g; 95% CI -580, 260). The pooled analysis revealed no statistically significant difference in childhood height. CONCLUSIONS: In vitro fertilisation/ICSI was not associated with long-term weight and height. TWEETABLE ABSTRACT: Children born following IVF/ICSI do not have impaired long-term weight or height compared with spontaneously conceived children.


Assuntos
Estatura , Peso Corporal , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil , Pré-Escolar , Estudos de Coortes , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Lactente , Recém-Nascido , Gravidez , Resultado da Gravidez , Fatores de Risco
4.
J Microsc ; 272(3): 165-179, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29655273

RESUMO

Many biological tissues have a complex hierarchical structure allowing them to function under demanding physiological loading conditions. Structural changes caused by ageing or disease can lead to loss of mechanical function. Therefore, it is necessary to characterise tissue structure to understand normal tissue function and the progression of disease. Ideally intact native tissues should be imaged in 3D and under physiological loading conditions. The current published in situ imaging methodologies demonstrate a compromise between imaging limitations and maintaining the samples native mechanical function. This review gives an overview of in situ imaging techniques used to visualise microstructural deformation of soft tissue, including three case studies of different tissues (tendon, intervertebral disc and artery). Some of the imaging techniques restricted analysis to observational mechanics or discrete strain measurement from invasive markers. Full-field local surface strain measurement has been achieved using digital image correlation. Volumetric strain fields have successfully been quantified from in situ X-ray microtomography (micro-CT) studies of bone using digital volume correlation but not in soft tissue due to low X-ray transmission contrast. With the latest developments in micro-CT showing in-line phase contrast capability to resolve native soft tissue microstructure, there is potential for future soft tissue mechanics research where 3D local strain can be quantified. These methods will provide information on the local 3D micromechanical environment experienced by cells in healthy, aged and diseased tissues. It is hoped that future applications of in situ imaging techniques will impact positively on the design and testing of potential tissue replacements or regenerative therapies. LAY DESCRIPTION: The soft tissues in our bodies, such as tendons, intervertebral discs and arteries, have evolved to have complicated structures which deform and bear load during normal function. Small changes in these structures can occur with age and disease which then leads to loss of function. Therefore, it is important to image tissue microstructure in 3D and under functional conditions. This paper gives an overview of imaging techniques used to record the deformation of soft tissue microstructures. Commonly there are compromises between obtaining the best imaging result and retaining the samples native structure and function. For example, invasive markers and dissecting samples damages the tissues natural structure, and staining or clearing (making the tissue more transparent) can distort tissue structure. Structural deformation has been quantified from 2D imaging techniques (digital image correlation) to create surface strain maps which help identify local tissue mechanics. When extended to 3D (digital volume correlation), deformation measurement has been limited to bone samples using X-ray micro-CT. Recently it has been possible to image the 3D structure of soft tissue using X-ray micro-CT meaning that there is potential for internal soft tissue mechanics to be mapped in 3D. Future application of micro-CT and digital volume correlation will be important for soft tissue mechanics studies particularly to understand normal function, progression of disease and in the design of tissue replacements.


Assuntos
Imageamento Tridimensional , Microtomografia por Raio-X/métodos , Tecido Conjuntivo , Humanos
5.
BJOG ; 122(13): 1728-38, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25395365

RESUMO

OBJECTIVE: To examine the effects of pre-pregnancy alcohol drinking on child neuropsychological functioning. DESIGN: Prospective follow-up study. SETTING AND POPULATION: 154 women and their children sampled from the Danish National Birth Cohort. METHODS: Participants were sampled based on maternal alcohol consumption before pregnancy. At 5 years of age, the children were tested with the Wechsler Preschool and Primary Scale of Intelligence-Revised, the Test of Everyday Attention for Children at Five (TEACh-5), and the Movement Assessment Battery for Children (MABC). The Behaviour Rating Inventory of Executive Function (BRIEF) was completed by the mothers and a preschool teacher. Parental education, maternal IQ, prenatal maternal smoking, child's age at testing, child's sex, and maternal alcohol intake during pregnancy were considered potential confounders. MAIN OUTCOME MEASURES: Performance on the Wechsler Preschool and Primary Scale of Intelligence-Revised, the TEACh-5, the MABC, and the BRIEF. RESULTS: Intake of 15-21 drinks/week on average prior to pregnancy was not associated with any of the outcomes, but intake of ≥22 drinks/week on average was associated with a significantly lower adjusted mean full scale IQ and lower adjusted means in overall attention and sustained attention score, but not in selective attention score or any of the BRIEF index scores or MABC scores. CONCLUSIONS: Intake of ≥22 drinks/week before pregnancy was associated with lower mean full scale IQ, overall attention and sustained attention. Assessment of pre-pregnancy drinking provides additional information regarding potential prenatal alcohol exposure and its implications for child neurodevelopment.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Atenção , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Inteligência , Masculino , Testes Neuropsicológicos , Gravidez , Estudos Prospectivos , Testes Psicológicos , Fatores de Risco , Adulto Jovem
6.
BJOG ; 121(13): 1642-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24910085

RESUMO

OBJECTIVE: To assess the association of fertility treatment and subfertility with offspring intelligence, attention, and executive functions in 5-year-old singletons. DESIGN: Follow-up study. SETTING: Denmark 2003-2008. POPULATION: A cohort of 1782 children sampled from the Danish National Birth Cohort. METHODS: The children were tested with a neuropsychological battery at age five. In addition to tests of intelligence, attention and executive functions, the follow up included extensive information on important covariates. The analyses were conducted using multiple linear regression and adjusted for parental educational level, maternal intelligence, age, parity, body mass index, smoking in pregnancy, alcohol consumption in pregnancy and child gender, child age, and examiner. MAIN OUTCOME MEASURES: Wechsler Preschool and Primary Scale of Intelligence-Revised, the Test of Everyday Attention for Children at Five, and the Behavior Rating Inventory of Executive Functions scores. RESULTS: A consistent pattern of nonsignificantly lower scores were only observed for intelligence and executive functions in children born after fertility treatment or by subfertile parents when the results were unadjusted for maternal intelligence and parental educational level. When adjusted for these and other covariates, there were no significant mean differences in intelligence (mean difference -2.8, 95% CI -7.8, 2.2), overall attention (-0.1, 95% CI -0.6, 0.3), or parent-rated executive functions (-0.1, 95% CI -3.0, 2.9) between children born after spontaneous conception and children born to parents conceiving after fertility treatment. Similarly, there were no significant mean differences in intelligence (mean difference 0.6, 95% CI -2.2, 3.4), overall attention (0.1, 95% CI -0.2, 0.4), or parent-rated executive functions (1.0, 95% CI -1.8, 3.7) between children born after spontaneous conception and children born to subfertile parents waiting more than 12 months before conceiving naturally. CONCLUSIONS: This study suggests that parental subfertility and fertility treatment are unrelated to offspring intelligence, attention and executive functions.


Assuntos
Atenção , Desenvolvimento Infantil , Deficiências do Desenvolvimento/epidemiologia , Função Executiva , Infertilidade/epidemiologia , Inteligência , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Técnicas de Reprodução Assistida/estatística & dados numéricos , Tempo para Engravidar , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Índice de Massa Corporal , Pré-Escolar , Estudos de Coortes , Dinamarca , Escolaridade , Feminino , Seguimentos , Humanos , Modelos Lineares , Masculino , Testes Neuropsicológicos , Pais , Gravidez , Fumar/epidemiologia , Escalas de Wechsler
7.
J Mech Behav Biomed Mater ; 138: 105579, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36463809

RESUMO

In-line phase contrast synchrotron tomography combined with in situ mechanical loading enables the characterisation of soft tissue micromechanics via digital volume correlation (DVC) within whole organs. Optimising scan time is important for reducing radiation dose from multiple scans and to limit sample movement during acquisition. Also, although contrasted edges provided by in-line phase contrast tomography of soft tissues are useful for DVC, the effect of phase contrast imaging on its accuracy has yet to be investigated. Due to limited time at synchrotron facilities, scan parameters are often decided during imaging and their effect on DVC accuracy is not fully understood. Here, we used previously published data of intervertebral disc phase contrast tomography to evaluate the influence of i) fibrous image texture, ii) number of projections, iii) tomographic reconstruction method, and iv) phase contrast propagation distance on DVC results. A greater understanding of how image texture influences optimal DVC tracking was obtained by visualising objective function mapping, enabling tracking inaccuracies to be identified. When reducing the number of projections, DVC was minimally affected by image high frequency noise but with a compromise in accuracy. Iterative reconstruction methods improved image signal-to-noise and consequently significantly lowered DVC displacement uncertainty. Propagation distance was shown to affect DVC accuracy. Consistent DVC results were achieved within a propagation distance range which provided contrast to the smallest scale features, where; too short a distance provided insufficient features to track, whereas too long led to edge effect inconsistencies, particularly at greater deformations. Although limited to a single sample type and image setup, this study provides general guidelines for future investigations when optimising image quality and scan times for in situ phase contrast x-ray tomography of fibrous connective tissues.


Assuntos
Disco Intervertebral , Disco Intervertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Síncrotrons , Fatores de Tempo
8.
Acta Biomater ; 138: 361-374, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34644611

RESUMO

Many soft tissues, such as the intervertebral disc (IVD), have a hierarchical fibrous composite structure which suffers from regional damage. We hypothesise that these tissue regions have distinct, inherent fibre structure and structural response upon loading. Here we used synchrotron computed tomography (sCT) to resolve collagen fibre bundles (∼5µm width) in 3D throughout an intact native rat lumbar IVD under increasing compressive load. Using intact samples meant that tissue boundaries (such as endplate-disc or nucleus-annulus) and residual strain were preserved; this is vital for characterising both the inherent structure and structural changes upon loading in tissue regions functioning in a near-native environment. Nano-scale displacement measurements along >10,000 individual fibres were tracked, and fibre orientation, curvature and strain changes were compared between the posterior-lateral region and the anterior region. These methods can be widely applied to other soft tissues, to identify fibre structures which cause tissue regions to be more susceptible to injury and degeneration. Our results demonstrate for the first time that highly-localised changes in fibre orientation, curvature and strain indicate differences in regional strain transfer and mechanical function (e.g. tissue compliance). This included decreased fibre reorientation at higher loads, specific tissue morphology which reduced capacity for flexibility and high strain at the disc-endplate boundary. STATEMENT OF SIGNIFICANCE: The analyses presented here are applicable to many collagenous soft tissues which suffer from regional damage. We aimed to investigate regional intervertebral disc (IVD) structural and functional differences by characterising collagen fibre architecture and linking specific fibre- and tissue-level deformation behaviours. Synchrotron CT provided the first demonstration of tracking discrete fibres in 3D within an intact IVD. Detailed analysis of regions was performed using over 200k points, spaced every 8 µm along 10k individual fibres. Such comprehensive structural characterisation is significant in informing future computational models. Morphological indicators of tissue compliance (change in fibre curvature and orientation) and fibre strain measurements revealed localised and regional differences in tissue behaviour.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Animais , Colágeno , Matriz Extracelular , Disco Intervertebral/diagnóstico por imagem , Ratos , Síncrotrons , Tomografia Computadorizada por Raios X
9.
Curr Med Chem ; 26(25): 4786-4798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30836908

RESUMO

BACKGROUND: Preeclapmsia (PE) is characterized by early onset symptoms such as elevated blood pressure, proteinuria and edema in the pregnant woman, and may result in seizures in the affected female. Currently, there are no therapeutic drugs available to treat this condition, but there are interventions to regulate the symptoms based on the gestational period of the fetus, although the largely favored option is delivery of the fetus and placenta. OBJECTIVE: A search for biomolecules associated with PE was conducted so as to identify diagnostic markers and therapeutic leads. RESULTS: The literature search resulted in the identification of biomolecules such as Corin and Placental Protein 13 (PP13), among others that are associated with PE. Thereby, giving an insight into the various mechanistic pathways involved in the causation of PE. However, it is also evident that PE cannot be solely attributed to any single mechanism but is due to an interplay of different factors that have led to the development of this disease condition. CONCLUSION: The identified biomarkers would ultimately help in understanding this complex disease and perhaps lead to the discovery of potential effective molecular targets for clinical trials, thereby providing a valuable therapeutic option for affected pregnant women.


Assuntos
Adenosina/uso terapêutico , Pré-Eclâmpsia/tratamento farmacológico , Vasodilatadores/uso terapêutico , Animais , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/metabolismo , Gravidez
10.
Acta Biomater ; 92: 290-304, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31082569

RESUMO

The intervertebral disc (IVD) has a complex and multiscale extracellular matrix structure which provides unique mechanical properties to withstand physiological loading. Low back pain has been linked to degeneration of the disc but reparative treatments are not currently available. Characterising the disc's 3D microstructure and its response in a physiologically relevant loading environment is required to improve understanding of degeneration and to develop new reparative treatments. In this study, techniques for imaging the native IVD, measuring internal deformation and mapping volumetric strain were applied to an in situ compressed ex vivo rat lumbar spine segment. Synchrotron X-ray micro-tomography (synchrotron CT) was used to resolve IVD structures at microscale resolution. These image data enabled 3D quantification of collagen bundle orientation and measurement of local displacement in the annulus fibrosus between sequential scans using digital volume correlation (DVC). The volumetric strain mapped from synchrotron CT provided a detailed insight into the micromechanics of native IVD tissue. The DVC findings showed that there was no slipping at lamella boundaries, and local strain patterns were of a similar distribution to the previously reported elastic network with some heterogeneous areas and maximum strain direction aligned with bundle orientation, suggesting bundle stretching and sliding. This method has the potential to bridge the gap between measures of macro-mechanical properties and the local 3D micro-mechanical environment experienced by cells. This is the first evaluation of strain at the micro scale level in the intact IVD and provides a quantitative framework for future IVD degeneration mechanics studies and testing of tissue engineered IVD replacements. STATEMENT OF SIGNIFICANCE: Synchrotron in-line phase contrast X-ray tomography provided the first visualisation of native intact intervertebral disc microstructural deformation in 3D. For two annulus fibrosus volumes of interest, collagen bundle orientation was quantified and local displacement mapped as strain. Direct evidence of microstructural influence on strain patterns could be seen such as no slipping at lamellae boundaries and maximum strain direction aligned with collagen bundle orientation. Although disc elastic structures were not directly observed, the strain patterns had a similar distribution to the previously reported elastic network. This study presents technical advances and is a basis for future X-ray microscopy, structural quantification and digital volume correlation strain analysis of soft tissue.


Assuntos
Disco Intervertebral/patologia , Estresse Mecânico , Síncrotrons , Tomografia , Animais , Anel Fibroso/patologia , Colágeno/metabolismo , Degeneração do Disco Intervertebral/patologia , Masculino , Ratos Sprague-Dawley
11.
Acta Biomater ; 3(3): 321-30, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17321811

RESUMO

The current design requirement for a tissue engineering skin substitute is that of a biodegradable scaffold through which fibroblasts can migrate and populate. This artificial "dermal layer" needs to adhere to and integrate with the wound, which is not always successful for the current artificial dermal analogues available. The high cost of these artificial dermal analogues also makes their application prohibitive both to surgeons and patients. We propose a cost-effective composite consisting of a nanofibrous scaffold directly electrospun onto a polyurethane dressing (Tegaderm, 3M Medical) - which we call the Tegaderm-nanofiber (TG-NF) construct - for dermal wound healing. Cell culture is performed on both sides of the nanofibrous scaffold and tested for fibroblast adhesion and proliferation. It is hoped that these studies will result in a fibroblast-populated three-dimensional dermal analogue that is feasible for layered applications to build up thickness of dermis prior to re-epithelialization. Results obtained in this study suggest that both the TG-NF construct and dual-sided fibroblast-populated nanofiber construct achieved significant cell adhesion, growth and proliferation. This is a successful first step for the nanofiber construct in establishing itself as a suitable three-dimensional scaffold for autogenous fibroblast populations, and providing great potential in the treatment of dermal wounds through layered application.


Assuntos
Gelatina/química , Nanoestruturas/química , Poliésteres/química , Pele Artificial , Engenharia Tecidual/métodos , Cicatrização/fisiologia , Materiais Biocompatíveis , Adesão Celular , Contagem de Células , Proliferação de Células , Células Cultivadas , Fibroblastos/fisiologia , Gelatina/classificação , Gelatina/ultraestrutura , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanotecnologia , Poliuretanos/química , Pele Artificial/economia , Fatores de Tempo
12.
J Clin Pathol ; 59(12): 1283-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16603646

RESUMO

AIMS: To evaluate the nuclear morphometric features of breast columnar cell lesions (CCLs) observed on mammotome core biopsies, to determine if there are significant measurable differences between those with atypia and those without. Correlation with follow-up open excision specimens was made. METHODS: Mammotome core biopsies performed on patients that contained CCLs were derived from the departmental case files. Histological material was reviewed and foci of CCLs demarcated for nuclear morphometric assessment, which was accomplished using an imaging system. Nuclear parameters studied were nuclear area and perimeter, circularity factor and feret's diameter. Statistical analysis used the GraphPad Prism software, with p<0.05 indicating significance. RESULTS: On examination of core biopsies of 40 patients with CCLs, 8 lesions were benign, 4 showed atypical lobular hyperplasia, 8 showed CCLs with nuclear atypia, 19 disclosed atypical ductal hyperplasia (ADH) and 1 showed ductal carcinoma in situ (DCIS). The nuclear area, perimeter and feret's diameter of CCLs with atypia were significantly greater than those without (p = 0.04, 0.03 and 0.019, respectively), whereas no difference was observed in the circularity factor. Follow-up open excision biopsy specimens in 24 patients showed upgrading to DCIS in 40% of cases diagnosed initially with ADH on core biopsy compared with 20% of CCLs with atypia. CONCLUSIONS: Nuclear morphometry in CCLs confirms nuclear size as the key parameter in the assessment of nuclear atypia. Whether it can be potentially used as an adjunctive tool depends on the establishment of appropriate cut-offs.


Assuntos
Neoplasias da Mama/ultraestrutura , Mama/ultraestrutura , Tamanho do Núcleo Celular , Núcleo Celular/patologia , Lesões Pré-Cancerosas/ultraestrutura , Adulto , Biópsia , Mama/patologia , Carcinoma Intraductal não Infiltrante/ultraestrutura , Progressão da Doença , Feminino , Seguimentos , Humanos , Hiperplasia/patologia , Pessoa de Meia-Idade
13.
Int J Mol Med ; 17(2): 385-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16391841

RESUMO

Keloids are proliferative growths of dermal collagen, usually resulting from excessive tissue response during wound healing. There is evidence that keratinocytes may promote keloidogenesis via epithelial-mesenchymal interactions. Metallothioneins (MTs) are known to be involved in the fundamental cellular processes of growth and apoptosis. In this study, we evaluated the expression of MT isoforms in normal and keloid keratinocytes. The expression patterns of ten functional MT isoforms were assessed using real-time RT-PCR in primary cultures of normal and keloid keratinocytes. The MT-2A isoform was the most abundant MT isoform in both normal and keloid keratinocytes while the MT-1B isoform was absent. There was a significant increase in the mRNA expression of four MT isoforms, viz. MT-1A, 1E, 1F and 2A in keloid keratinocytes as compared to normal keratinocytes. Up-regulation of MT-1A, 1E, 1F and 2A isoforms may play a part in the development of keloids by paracrine signaling.


Assuntos
Queloide/genética , Queloide/patologia , Queratinócitos/metabolismo , Metalotioneína/genética , Regulação para Cima/genética , Células Cultivadas , Humanos , Queratinócitos/ultraestrutura , Microscopia Eletrônica de Transmissão , Isoformas de Proteínas/genética , RNA Mensageiro/genética
14.
Curr Med Chem ; 23(2): 186-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26549431

RESUMO

Nasopharyngeal carcinoma (NPC) is a cancer of the nasopharyngeal epithelium with distinct geographical, ethnic and racial distribution. Several genetic, ethnic and environmental risk factors, have been implicated in nasopharyngeal pathogenesis and of significance, is the Epstein - Barr virus (EBV)- latent infection observed in most patients. Patients with NPC are typically diagnosed only in advanced stages due to non-specific symptoms, and hence, they respond poorly to therapy. Currently, low survival rates, severe complications, tumour metastasis and recurrence following chemo-radiotherapy, delineate the need for better therapeutic options to combat the disease. Recent studies have shown that epigenetic mechanisms such as DNA methylation, histone modifications and microRNAs, which are altered in the EBV genome as well as in the host cells, may underlie the initiation and progression of NPC. Histone acetylation and deacetylation which are mediated by enzymes, namely histone acetyl transferases (HATs) and histone deacetylases (HDACs), are known to regulate gene expression and several cellular processes. HDACs are also involved in maintaining the EBV latent cycle and thus, HDAC inhibitors (HDACi) are potent inducers of EBV reactivation, which is critical for the expression of the lytic proteins, thereby providing novel targets for therapy, as well as mediating enhanced killing of cancer cells, when used alone or along with additional anti-cancer agents in EBV associated malignancies. Recently, three FDA- approved HDACi have been used for the treatment of T-cell lymphoma, while several others are in clinical trials, making histone modifications excellent candidates for targeted therapy. In this review, we summarize the epigenetic mechanisms altered in NPC, with a focus on histone modifications for targeted therapy.


Assuntos
Antivirais/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Terapia de Alvo Molecular , Neoplasias Nasofaríngeas/metabolismo , Antivirais/química , Epigênese Genética/efeitos dos fármacos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Humanos , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/virologia
15.
Mol Endocrinol ; 14(3): 348-58, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10707953

RESUMO

Since the effects of progesterone are mediated mainly via estrogen-dependent progesterone receptor (PR), the expression of the effects of progesterone may be masked or overridden by the influence of estrogen under conditions in which priming with estrogens is required. We have established a PR-positive but estrogen receptor-alpha (ER-alpha) negative breast cancer cell model by transfecting PR cDNA into ER-alpha- and PR-negative MDA-MB-231 cells in order that the functions of progesterone can be studied independently of estrogens. We have demonstrated using this model that progesterone markedly inhibited cell growth. We have also discovered that progesterone induced remarkable changes in cell morphology and specific adhesion structures. Progesterone-treated cells became considerably more flattened and well spread than vehicle-treated control cells. This was associated with a striking increase of stress fibers, both in number and diameter, and increased focal contacts as shown by the staining of focal adhesion proteins paxillin and talin. There were also distinct increases in tyrosine phosphorylation of focal adhesion protein paxillin and focal adhesion kinase in association with increased focal adhesion. The staining of tyrosine-phosphorylated proteins was concentrated at focal adhesions in progesterone-treated cells. More interestingly, monoclonal antibody (Ab) to beta1 integrin was able to inhibit progesterone-induced cell spreading and formation of actin cytoskeleton. To our knowledge, this is the first report describing a direct effect of progesterone in inducing spreading and adhesion of breast cancer cells, and beta1-integrin appeared to play an essential role in the effect. It is known that the initial step of tumor metastasis is the breakaway of tumor cells from primary tumor mass when they lose the ability to attach. Hence, progesterone-induced cell spreading and adhesion may have significant implications in tumor metastasis.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Adesão Celular/efeitos dos fármacos , Progesterona/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Moléculas de Adesão Celular/metabolismo , Tamanho Celular , Proteínas do Citoesqueleto/metabolismo , DNA Complementar/genética , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Feminino , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Integrina beta1/fisiologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Paxilina , Fosfoproteínas/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Tirosina Quinases/metabolismo , Receptores de Estrogênio/deficiência , Receptores de Estrogênio/fisiologia , Receptores de Progesterona/genética , Receptores de Progesterona/fisiologia , Proteínas Recombinantes de Fusão/fisiologia , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas/efeitos dos fármacos
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 1011-8, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25171051

RESUMO

In this study, 5-(benzylthio)-1-cylopentyl-1H-tetrazole (5B1C1HT) have been synthesized. Boiling points of the obtained compound have been determined and it has been characterized by FT-IR, (1)H NMR, (13)C-APT and LC-MS spectroscopy techniques. The FT-IR, (1)H NMR and (13)C-APT spectral measurements of the 5B1C1HT compound and complete assignment of the vibrational bands observed in spectra has been discussed. The spectra were interpreted with the aid of normal coordinate analysis following full structure optimization and force field calculations based on Density Functional Theory (DFT) at 6-311++G(**), cc-pVDZ and cc-pVTZ basis sets. The optimized geometry with 6-311++G(**) basis sets were used to determine the total energy distribution, harmonic vibrational frequencies, IR intensities.


Assuntos
Modelos Moleculares , Tetrazóis/química , Tetrazóis/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Elétrons , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Vibração
17.
FEBS Lett ; 474(2-3): 208-12, 2000 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-10838086

RESUMO

Spider venoms contain toxins that specifically immobilize and kill insects. We report the purification and characterization of a new insect-specific toxin named covalitoxin-II (Cvtx-II; mass, 3406. 24+/-0.64), from Coremiocnemis validus (Singapore tarantula) venom. The complete 31 amino acid sequence of Cvtx-II has been determined and it shows less than 40% identity with spider toxins. However, Cvtx-II has conserved cystine motif analogous to other spider and omega-conotoxins. Cvtx-II was chemically synthesized and identified with the native Cvtx-II. Synthetic Cvtx-II induced insect-specific non-lethal excitatory activity when injected into crickets, but not in cockroaches and mice.


Assuntos
Neurotoxinas/química , Neurotoxinas/isolamento & purificação , Venenos de Aranha/química , Venenos de Aranha/isolamento & purificação , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Baratas/efeitos dos fármacos , Baratas/fisiologia , Cistina/metabolismo , Gryllidae/efeitos dos fármacos , Gryllidae/fisiologia , Locomoção/efeitos dos fármacos , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , Peso Molecular , Atividade Motora/efeitos dos fármacos , Neurotoxinas/síntese química , Neurotoxinas/toxicidade , Paralisia/induzido quimicamente , Estrutura Secundária de Proteína , Alinhamento de Sequência , Especificidade da Espécie , Venenos de Aranha/síntese química , Venenos de Aranha/toxicidade
18.
Cancer Lett ; 104(2): 145-52, 1996 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-8665482

RESUMO

The effect of staurosporine, an antimicrobial agent and inhibitor of protein kinase C (PKC) on programmed cell death/apoptosis (PCD) was investigated in the human oral cavity epidermoid carcinoma KB cell line. Staurosporine-treated oral KB carcinoma cells exhibited morphological features characteristic of apoptosis such as (a) cell shrinkage and increased nuclear fluorescence (quantitated by image analysis with laser scanning confocal microscopy), (b) nuclear condensation and fragmentation observed under fluorescence microscopy with propidium-iodide-DNA staining and (c) chromatin condensation seen under transmission electron microscopy. Specific terminal deoxynucleotidyl transferase (TdT)-mediated labeling of 3'OH ends of DNA breaks in staurosporine-treated cells confirmed DNA fragmentation. In addition, we show the concomitant existence of M-phase PCD with interphase PCD in staurosporine-treated KB cells. It would appear that staurosporine induces apoptosis regardless of the cell cycle phase and that mitosis and apoptosis are not necessarily mutually exclusive events.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Interfase/efeitos dos fármacos , Mitose/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Humanos , Células KB , Estaurosporina , Células Tumorais Cultivadas
19.
Cancer Lett ; 155(1): 99-104, 2000 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-10814885

RESUMO

Metallothionein (MT) is a metal-binding protein with functional roles in cell growth, repair and differentiation. MT is reported to be differentially expressed in lymphocytes of malignant gastrointestinal lesions. The level of MT protein was examined by immunohistochemical analysis at light microscopic and ultrastructural level in infiltrating lymphocytes from 20 cases of undifferentiated nasopharyngeal carcinoma (NPC). MT expression was found to be absent in the infiltrating lymphocytes of NPC and in reactive lymphocytes of lymphoid hyperplasia in nasopharyngeal tissues. Ultrastructural examination confirmed the absence of MT immunoreactivity in the lymphoid infiltrate of NPC. On the other hand, malignant lymphoblasts of diffuse large cell lymphoma, showed MT-immunopositivity by immunoelectron microscopy. This study demonstrates a lack of MT expression in the lymphoid stroma of undifferentiated NPC, a further characteristic of its non-neoplastic nature.


Assuntos
Linfócitos do Interstício Tumoral/metabolismo , Metalotioneína/biossíntese , Neoplasias Nasofaríngeas/metabolismo , Adulto , Idoso , Carcinoma/metabolismo , Carcinoma/ultraestrutura , Feminino , Humanos , Imuno-Histoquímica , Linfócitos do Interstício Tumoral/ultraestrutura , Linfoma de Células B/metabolismo , Masculino , Microscopia Eletrônica , Microscopia Imunoeletrônica , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/ultraestrutura
20.
Cancer Lett ; 207(2): 175-81, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15072826

RESUMO

Photodynamic therapy (PDT) is a new modality of treatment for cancer. Hypericin is a photosensitizer, which is known to generate reactive oxygen species upon activation with light. We observed that photoactivated hypericin induces the generation of reactive oxygen intermediates in nasopharyngeal cancer (NPC) cells in vitro. There was also significant reduction of Glutathione S-transferase (GST) activity in HK1 and CNE-2 NPC cells and in tumor tissues from the NPC/HK1 murine tumor model by hypericin-mediated PDT. As antioxidants protect cells against phototoxicity, down-regulation of GST activity would potentiate the efficacy of hypericin-PDT treatment.


Assuntos
Glutationa Transferase/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Perileno/análogos & derivados , Perileno/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Antracenos , Diferenciação Celular , Divisão Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Confocal , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/patologia , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
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