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1.
Hum Reprod ; 29(12): 2628-36, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25316447

RESUMO

STUDY QUESTION: Is in vitro fertilization treatment with or without intracytoplasmatic sperm injection (IVF/ICSI) associated with changes in first and second trimester embryonic and fetal growth trajectories and birthweight in singleton pregnancies? SUMMARY ANSWER: Embryonic and fetal growth trajectories and birthweight are not significantly different between pregnancies conceived with IVF/ICSI treatment and spontaneously conceived pregnancies with reliable pregnancy dating. WHAT IS KNOWN ALREADY: IVF/ICSI treatment has been associated with increased risks of preterm birth, fetal growth restriction and low birthweight. Decreased first-trimester crown-rump length (CRL) in the general population has been inversely associated with the same adverse pregnancy outcomes. STUDY DESIGN, SIZE, DURATION: In a prospective periconception birth cohort study conducted in a tertiary centre, 146 singleton pregnancies with reliable pregnancy dating and nonmalformed live borns were investigated, comprised of 88 spontaneous and 58 IVF/ICSI pregnancies. PARTICIPANTS/MATERIALS, SETTING, METHODS: Serial 3D ultrasound scans were performed from 6 to 12 weeks of gestation. As estimates of embryonic growth, CRL and embryonic volume (EV) were measured using the I-Space virtual reality system. General characteristics were obtained from self-administered questionnaires at enrolment. Fetal growth parameters at 20 weeks and birthweight were obtained from medical records. To assess associations between IVF/ICSI and embryonic growth trajectories, estimated fetal weight and birthweight, stepwise linear mixed model analyses and linear regression analyses were performed using square root transformed CRL and fourth root transformed EV. MAIN RESULTS AND THE ROLE OF CHANCE: In 146 pregnancies, 934 ultrasound scans were performed of which 849 (90.9%) CRLs and 549 (58.8%) EVs could be measured. Embryonic growth trajectories were comparable between IVF/ICSI pregnancies and spontaneously conceived pregnancies (CRL: ßIVF/ICSI = 0.10√mm; P = 0.10; EV: ßIVF/ICSI = 0.03(4)√cm³; P = 0.13). Estimated fetal weight and birthweight were also comparable between both groups (ßIVF/ICSI = 6 g; P = 0.36 and ßIVF/ICSI = 80 g; P = 0.24, respectively). LIMITATIONS, REASONS FOR CAUTION: Variations in embryonic growth trajectories of spontaneously conceived pregnancies with reliable pregnancy dating may partially be a result of less precise pregnancy dating and differences in endometrium receptivity compared with IVF/ICSI pregnancies. WIDER IMPLICATIONS OF THE FINDINGS: The absence of a significant difference in embryonic and fetal growth trajectories suggests safety of IVF/ICSI treatment with regard to early embryonic growth. However, further research is warranted to ascertain the influence of IVF/ICSI treatments in a larger study population, and to estimate the impact of the underlying causes of the subfertility and other periconceptional exposures on human embryonic and fetal growth trajectories. FUNDING STATEMENT: This study was supported by the Department of Obstetrics and Gynaecology of the Erasmus MC, University Medical Centre. CONFLICT OF INTEREST: No competing interests are declared.


Assuntos
Desenvolvimento Embrionário , Fertilização in vitro/efeitos adversos , Desenvolvimento Fetal , Adulto , Feminino , Humanos , Modelos Lineares , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Ultrassonografia Pré-Natal
2.
Hum Reprod ; 29(2): 201-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24287820

RESUMO

STUDY QUESTION: Can reliable size charts of human embryonic brain structures be created from three-dimensional ultrasound (3D-US) visualizations? SUMMARY ANSWER: Reliable size charts of human embryonic brain structures can be created from high-quality images. WHAT IS KNOWN ALREADY: Previous studies on the visualization of both the cavities and the walls of the brain compartments were performed using 2D-US, 3D-US or invasive intrauterine sonography. However, the walls of the diencephalon, mesencephalon and telencephalon have not been measured non-invasively before. Last-decade improvements in transvaginal ultrasound techniques allow a better visualization and offer the tools to measure these human embryonic brain structures with precision. STUDY DESIGN, SIZE, DURATION: This study is embedded in a prospective periconceptional cohort study. A total of 141 pregnancies were included before the sixth week of gestation and were monitored until delivery to assess complications and adverse outcomes. PARTICIPANTS/MATERIALS, SETTING, METHODS: For the analysis of embryonic growth, 596 3D-US scans encompassing the entire embryo were obtained from 106 singleton non-malformed live birth pregnancies between 7(+0) and 12(+6) weeks' gestational age (GA). Using 4D View (3D software) the measured embryonic brain structures comprised thickness of the diencephalon, mesencephalon and telencephalon, and the total diameter of the diencephalon and mesencephalon. MAIN RESULTS AND THE ROLE OF CHANCE: Of 596 3D scans, 161 (27%) high-quality scans of 79 pregnancies were eligible for analysis. The reliability of all embryonic brain structure measurements, based on the intra-class correlation coefficients (ICCs) (all above 0.98), was excellent. Bland-Altman plots showed moderate agreement for measurements of the telencephalon, but for all other measurements the agreement was good. Size charts were constructed according to crown-rump length (CRL). LIMITATIONS, REASONS FOR CAUTION: The percentage of high-quality scans suitable for analysis of these brain structures was low (27%). WIDER IMPLICATIONS OF THE FINDINGS:  The size charts of human embryonic brain structures can be used to study normal and abnormal development of brain development in future. Also, the effects of periconceptional maternal exposures, such as folic acid supplement use and smoking, on human embryonic brain development can be a topic of future research. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Department of Obstetrics and Gynaecology of the Erasmus University Medical Center. M.G. was supported by an additional grant from the Sophia Foundation for Medical Research (SSWO grant number 644). No competing interests are declared.


Assuntos
Encéfalo/embriologia , Tamanho do Órgão , Primeiro Trimestre da Gravidez , Adulto , Encéfalo/patologia , Estatura Cabeça-Cóccix , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional , Masculino , Análise Multivariada , Gravidez , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes , Ultrassonografia Pré-Natal
3.
BJOG ; 121(7): 821-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24517216

RESUMO

OBJECTIVE: To investigate the association between periconception maternal folate status and embryonic size. DESIGN: Prospective periconception cohort study. SETTING: Erasmus University Medical Centre, Rotterdam, the Netherlands. POPULATION: Seventy-seven singleton pregnancies recruited in 2009 and 2010. METHODS: We recruited women before 8 weeks of gestation and performed weekly three-dimensional ultrasound scans from enrolment up to 13 weeks of gestation. As a measure of embryonic growth, crown-rump length (CRL) measurements were performed using V-Scope software in the BARCO I-Space. Maternal blood was collected to determine first-trimester long-term red blood cell (RBC) folate status. Non-malformed live births were included in the analysis. We calculated quartiles of RBC folate, square root-transformed CRL data and performed multivariable linear mixed model analyses. MAIN OUTCOME MEASURES: Serial first-trimester CRL measurements. RESULTS: In total, 484 ultrasound scans were performed in 77 women, in 440 (90.7%) of which CRLs could be measured. RBC folate in the third quartile (1513-1812 nmol/l) was significantly associated with an increased CRL compared with the first two quartiles (814-1512 nmol/l) and the upper quartile (1813-2936 nmol/l; P(overall) = 0.03; adjusted for gestational age, smoking, body mass index and fetal sex). Compared with the third quartile, embryos in the upper quartile were 24.2% smaller at 6(+0) weeks [4.1 mm (95% confidence interval 3.5, 4.7) versus 5.4 mm (95% confidence interval 4.8, 6.1)] and 7.6% smaller at 12(+0) weeks [55.1 mm (95% confidence interval 52.9, 57.3) versus 59.6 mm (95% confidence interval 57.4, 62.0)] of gestation. CONCLUSIONS: This study suggests that a very high maternal periconception folate status is associated with reduced embryonic size. Whether these effects are beneficial or harmful requires further investigation.


Assuntos
Estatura Cabeça-Cóccix , Ácido Fólico/sangue , Adulto , Feminino , Humanos , Países Baixos , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal
4.
Hum Reprod ; 28(12): 3188-96, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24105824

RESUMO

STUDY QUESTION: Are maternal characteristics and lifestyle factors associated with human embryonic growth trajectories? SUMMARY ANSWER: Periconception maternal age is associated with increased, and smoking and alcohol use with decreased embryonic growth trajectories, estimated with crown-rump length (CRL) measurements. WHAT IS KNOWN ALREADY: Fetal weight is associated with health and disease in later life. Maternal characteristics and lifestyle factors affect fetal growth in the second and third trimesters of pregnancy and at birth; however, little is known about the association of these characteristics with first trimester embryonic growth. STUDY DESIGN, SIZE, DURATION: In a tertiary centre, pregnant women were recruited and enrolled in a prospective periconception cohort study before 8 weeks of gestation. We selected 87 spontaneously conceived singleton pregnancies of women recruited in 2009 and 2010 that ended in non-malformed live births. PARTICIPANTS/MATERIALS, SETTING, METHODS: We performed weekly three-dimensional ultrasound scans from enrolment up to 13 weeks of gestation. At enrolment, a questionnaire was completed. Embryonic CRL measurements were performed using the V-Scope software in the BARCO I-Space. Associations between maternal characteristics and embryonic growth were assessed using square root transformed CRL as response in linear mixed model analyses, adjusted for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Four hundred and ninety-six scans from 87 pregnancies were included. In the multivariable analysis, maternal age was positively associated with first trimester CRL (difference per maternal year of age 0.024√mm (95% confidence interval (CI) 0.009, 0.040), P = 0.001). At 6 and 12 weeks of gestation, the CRL of an embryo from a 40-year-old mother was estimated 2.0 mm (61%) and 7.2 mm (14%) larger, respectively, compared with an embryo from a 20-year-old mother. Smoking of 10 or more cigarettes per day was negatively associated with CRL (difference -0.211√mm (95% CI -0.416, -0.006), P = 0.04), with embryos that were 0.9 mm (18.7%) and 3.1 mm (5.5%) smaller at 6 and 12 weeks, respectively, compared with non-smokers. Periconception alcohol use was negatively associated with CRL growth rate (difference -0.0025√mm (95% CI -0.0047, -0.0003)/day gestational age, P = 0.022), with embryos that were 0.2 mm (3%) and 1.1 mm (2%) smaller at 6 and 12 weeks, respectively, compared with non-alcohol users. Parity, BMI and moment of initiation of folic acid use were not significantly associated with embryonic CRL. LIMITATIONS, REASONS FOR CAUTION: Due to the selection of pregnancies in a tertiary centre and the small number of pregnancies, the external validity of the results has to be confirmed using larger sample sizes and other population-based periconception cohort studies. WIDER IMPLICATIONS OF THE FINDINGS: The association of maternal age and smoking with embryonic growth is in line with previous literature, whereas the association between embryonic growth and alcohol use is a new finding. However, concerning exposure to alcohol, the effect estimate was small and it is questionable whether this is of clinical value. More research is warranted to unravel underlying mechanisms and to assess the implications for preconception and early pregnancy care, such as the development and implementation of effective lifestyle interventions. STUDY FUNDING/COMPETING INTEREST(S): The work was funded by the Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. The authors declare no conflicts of interest.


Assuntos
Desenvolvimento Fetal , Idade Materna , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Estatura Cabeça-Cóccix , Feminino , Peso Fetal , Humanos , Estudos Longitudinais , Países Baixos , Gravidez , Estudos Prospectivos , Fumar/efeitos adversos
5.
Br J Cancer ; 106(3): 538-45, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22187034

RESUMO

BACKGROUND: We have recently demonstrated that expression profiling is a more accurate and objective method to classify gliomas than histology. Similar to most expression profiling studies, our experiments were performed using fresh frozen (FF) glioma samples whereas most archival samples are fixed in formalin and embedded in paraffin (FFPE). Identification of the same, expression-based intrinsic subtypes in FFPE-stored samples would enable validation of the prognostic value of these subtypes on these archival samples. In this study, we have therefore determined whether the intrinsic subtypes identified using FF material can be reproduced in FFPE-stored samples. METHODS: We have performed expression profiling on 55 paired FF-FFPE glioma samples using HU133 plus 2.0 arrays (FF) and Exon 1.0 ST arrays (FFPE). The median time in paraffin of the FFPE samples was 14.1 years (range 6.6-26.4 years). RESULTS: In general, the correlation between FF and FFPE expression in a single sample was poor. We then selected the most variable probe sets per gene (n=17,583), and of these, the 5000 most variable probe sets on FFPE expression profiles. This unsupervised selection resulted in a better concordance (R(2)=0.54) between expression of FF and FFPE samples. Importantly, this probe set selection resulted in a correct assignment of 87% of FFPE samples into one of seven intrinsic subtypes identified using FF samples. Assignment to the same molecular cluster as the paired FF tissue was not correlated to time in paraffin. CONCLUSION: We are the first to examine a large cohort of paired FF and FFPE samples. We show that expression data from FFPE material can be used to assign samples to intrinsic molecular subtypes identified using FF material. This assignment allows the use of archival material, including material derived from large-randomised clinical trials, to determine the predictive and/or prognostic value of 'intrinsic glioma subtypes' on Exon arrays. This would enable clinicians to provide patients with an objective and accurate diagnosis and prognosis, and a personalised treatment strategy.


Assuntos
Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica/métodos , Glioma/genética , Análise por Conglomerados , Fixadores , Formaldeído , Secções Congeladas , Regulação Neoplásica da Expressão Gênica , Humanos , Inclusão em Parafina/métodos , Reprodutibilidade dos Testes , Fixação de Tecidos/métodos
6.
Arterioscler Thromb Vasc Biol ; 27(11): 2310-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17717295

RESUMO

OBJECTIVE: The immune system is thought to play a crucial role in regulating collateral circulation (arteriogenesis), a vital compensatory mechanism in patients with arterial obstructive disease. Here, we studied the role of lymphocytes in a murine model of hindlimb ischemia. METHODS AND RESULTS: Lymphocytes, detected with markers for NK1.1, CD3, and CD4, invaded the collateral vessel wall. Arteriogenesis was impaired in C57BL/6 mice depleted for Natural Killer (NK)-cells by anti-NK1.1 antibodies and in NK-cell-deficient transgenic mice. Arteriogenesis was, however, unaffected in J alpha281-knockout mice that lack NK1.1+ Natural Killer T (NKT)-cells, indicating that NK-cells, rather than NKT-cells, are involved in arteriogenesis. Furthermore, arteriogenesis was impaired in C57BL/6 mice depleted for CD4+ T-lymphocytes by anti-CD4 antibodies, and in major histocompatibility complex (MHC)-class-II-deficient mice that more selectively lack mature peripheral CD4+ T-lymphocytes. This impairment was even more profound in anti-NK1.1-treated MHC-class-II-deficient mice that lack both NK- and CD4+ T-lymphocytes. Finally, collateral growth was severely reduced in BALB/c as compared with C57BL/6 mice, 2 strains with different bias in immune responsiveness. CONCLUSIONS: These data show that both NK-cells and CD4+ T-cells modulate arteriogenesis. Promoting lymphocyte activation may represent a promising method to treat ischemic disease.


Assuntos
Arteriopatias Oclusivas/imunologia , Linfócitos T CD4-Positivos/imunologia , Circulação Colateral/imunologia , Células Matadoras Naturais/imunologia , Neovascularização Fisiológica/imunologia , Animais , Arteriopatias Oclusivas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Modelos Animais de Doenças , Artéria Femoral/crescimento & desenvolvimento , Membro Posterior/irrigação sanguínea , Isquemia , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout
7.
Int J Gynecol Cancer ; 18(3): 432-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17692087

RESUMO

To evaluate the possibility to give a prediction of the future (disease-free) survival, given the fact that a patient with a history of early-stage cervical cancer has been disease free for a specific period after treatment. Between January 1984 and April 2005, 615 patients with cervical cancer stages I-IIA underwent radical hysterectomy with or without adjuvant radiotherapy. The Kaplan-Meier method was used to detect statistical significance and multistate risk models to estimate the influence of covariates and to generate predicted survival curves by simulation. Simulations were done for patients with positive lymph nodes (n= 123), patients with negative lymph nodes (n= 492), and 4 hypothetical patients. The 5-year cancer-specific survival and disease-free survival of the entire group was 84% and 76%, respectively. The probability of death of the two lymph node groups and the four hypothetical patients was demonstrated in predicted cumulative probability plots. It is possible with multistate risk models to give a detailed prediction of the future (disease-free) survival, given the fact that a patient has been disease free for a specific period after treatment. This possibility is an important step forward to improve the quality of cancer care.


Assuntos
Linfonodos/patologia , Recidiva Local de Neoplasia/mortalidade , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Histerectomia/métodos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Países Baixos , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Neoplasias do Colo do Útero/terapia
8.
J Chromatogr A ; 1118(2): 199-210, 2006 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-16643929

RESUMO

In this paper the performance of three alignment algorithms, correlation optimized warping, parametric time warping and semi-parametric time warping, is compared on real chromatograms. Among these, parametric time warping is the simplest and fastest; generally less than 1s is required to align two chromatograms. It does not require the optimization of input parameters and allows the alignment of peak shifts in only one direction, or non-complex peak shifts in both directions. With correlation optimized warping and semi-parametric time warping complex peak shifts in both directions can be corrected but at the expense of the optimization of two input parameters. Semi-parametric time warping requires the selection of the proper number of B-splines in the warping function and, if necessary, the optimization of the penalty parameter. Often the default values can be used to obtain aligned signals. The optimization of the input parameters for correlation optimized warping (section length, slack) is not easy and time-consuming. Moreover, dependent on the input parameters, the computation time of the correlation optimized warping algorithm can be twice as long as for semi-parametric time warping for which computation times up to 23 s are required. However, the performance of both algorithms is equally good considering the improvement of the precision of the peak retention times and correlation coefficients between the chromatograms, after alignment. For the data aligned in this study, the average retention time precision and the lowest correlation before warping were 14 and 0.17, and were improved to three and 0.83, and six and 0.87 after warping, with correlation optimized warping and semi-parametric time warping, respectively.


Assuntos
Algoritmos , Cromatografia Líquida de Alta Pressão/métodos , Chá/química
9.
J Plast Reconstr Aesthet Surg ; 68(2): 237-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25455286

RESUMO

The superficial branch of the radial nerve (SBRN) is known for developing neuropathic pain syndromes after trauma. These pain syndromes can be hard to treat due to the involvement of other nerves in the forearm. When a nerve is cut, the Schwann cells, and also other cells in the distal segment of the transected nerve, produce the nerve growth factor (NGF) in the entire distal segment. If two nerves overlap anatomically, similar to the lateral antebrachial cutaneous nerve (LACN) and SBRN, the increase in secretion of NGF, which is mediated by the injured nerve, results in binding to the high-affinity NGF receptor, tyrosine kinase A (TrkA). This in turn leads to possible sprouting and morphological changes of uninjured fibers, which ultimately causes neuropathic pain. The aim of this study was to map the level of overlap between the SBRN and LACN. Twenty arms (five left and 15 right) were thoroughly dissected. Using a new analysis tool called CASAM (Computer Assisted Surgical Anatomy Mapping), the course of the SBRN and LACN could be compared visually. The distance between both nerves was measured at 5-mm increments, and the number of times they intersected was documented. In 81% of measurements, the distance between the nerves was >10 mm, and in 49% the distance was even <5 mm. In 95% of the dissected arms, the SBRN and LACN intersected. On average, they intersected 2.25 times. The close (anatomical) relationship between the LACN and the SBRN can be seen as a factor in the explanation of persistent neuropathic pain in patients with traumatic or iatrogenic lesion of the SBRN or the LACN.


Assuntos
Nervo Musculocutâneo/anatomia & histologia , Neuralgia/etiologia , Nervo Radial/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Cadáver , Dor Crônica/etiologia , Feminino , Antebraço/inervação , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
10.
Hernia ; 19(1): 89-101, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25380560

RESUMO

PURPOSE: Incisional hernia (IH) is one of the most frequent postoperative complications. Of all patients undergoing IH repair, a vast amount have a hernia which can be defined as a large incisional hernia (LIH). The aim of this study is to identify the preferred technique for LIH repair. METHODS: A systematic review of the literature was performed and studies describing patients with IH with a diameter of 10 cm or a surface of 100 cm2 or more were included. Recurrence hazards per year were calculated for all techniques using a generalized linear model. RESULTS: Fifty-five articles were included, containing 3,945 LIH repairs. Mesh reinforced techniques displayed better recurrence rates and hazards than techniques without mesh reinforcement. Of all the mesh techniques, sublay repair, sandwich technique with sublay mesh and aponeuroplasty with intraperitoneal mesh displayed the best results (recurrence rates of <3.6%, recurrence hazard <0.5% per year). Wound complications were frequent and most often seen after complex LIH repair. CONCLUSIONS: The use of mesh during LIH repair displayed the best recurrence rates and hazards. If possible mesh in sublay position should be used in cases of LIH repair.


Assuntos
Hérnia Ventral/cirurgia , Herniorrafia/métodos , Telas Cirúrgicas , Hérnia Ventral/etiologia , Humanos , Implantação de Prótese
11.
Neuroscience ; 108(3): 359-63, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11738250

RESUMO

The circadian pacemaker of the suprachiasmatic nuclei is a complex multioscillator system, which controls circadian and seasonal rhythmicity. A number of clock genes have been identified that play a key role in the generation of circadian rhythms. These clock genes are expressed in a circadian manner as has been shown in mice, rats and hamsters. The time at which their expression reaches peak values differs among the several genes. Expression profiles for a specific gene may also differ among subdivisions of the suprachiasmatic nuclei. It has been shown that mPer1 peaks slightly out of phase in the left and right suprachiasmatic nuclei and that the rhythm in c-fos expression is significantly different between the dorsomedial and ventrolateral regions. In the special case that the animal shows splitting of its locomotor activity pattern, mPer1 in the left and right suprachiasmatic nuclei appeared to oscillate in antiphase. Whether the molecular organization within the suprachiasmatic nuclei plays a role in seasonal rhythmicity, allowing animals to track daylength and become reproductive at the proper phase of the annual cycle, receives increasing interest (). The differences in peak expression times that exist between different genes, and the spatial differences in peak time for single genes, are suggestive of a genetic mechanism underlying the multioscillator structure. It is unknown, however, whether phase differences that are observed at the molecular level exist at the level of electrical activity rhythms in the suprachiasmatic nuclei in order to become potentially functional. In this study we investigated the presence of phase differences in neuronal discharge rhythms in the suprachiasmatic nuclei of the rat. To this purpose we combined simultaneous electrophysiological recordings of neuronal populations in the left and right suprachiasmatic nuclei with a detailed analysis of the phase relationship between them. The results demonstrate that neuronal subpopulations of the suprachiasmatic nuclei show phase differences both in their peak and half-maximum times of up to 4 h. We propose that these phase differences may play a role in the plasticity of the circadian timing system.


Assuntos
Ritmo Circadiano/fisiologia , Neurônios/fisiologia , Núcleo Supraquiasmático/fisiologia , Animais , Simulação por Computador , Eletrofisiologia , Técnicas In Vitro , Modelos Neurológicos , Método de Monte Carlo , Ratos , Núcleo Supraquiasmático/citologia
12.
Behav Neurosci ; 117(5): 1076-85, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14570556

RESUMO

Antiepileptic drugs can suppress seizures completely, but they may also modify the appearance of drug-resistant seizures. In this study, the effects of three antiepileptic drugs on a seizure pattern were assessed by means of population pharmacokinetic/pharmacodynamic (PK/PD) modeling, yielding estimates of baseline response, EC50, and Hill slope. Lamotrigine did not affect eye closure, although it did suppress the other ictal signs in a concentration-dependent fashion. Midazolam suppressed forelimb clonus less potently than the other ictal signs; the same was observed for tiagabine with respect to eye closure. This study shows that ictal component analysis (ICA) in combination with PK/PD modeling may facilitate drug selection and dose optimization. The application of ICA is not restricted to a single seizure type or anticonvulsant drug and can be used to identify drug combinations that have a complementary action.


Assuntos
Anticonvulsivantes/farmacocinética , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Convulsões/metabolismo , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Relação Dose-Resposta a Droga , Estimulação Elétrica , Masculino , Ratos , Ratos Wistar , Convulsões/tratamento farmacológico
13.
Int J Tuberc Lung Dis ; 8(2): 232-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15139453

RESUMO

SETTING: Human observers generally have a strong tendency to round analog measurements or estimates to 'nice' ending digits, such as 0, 5, or even numbers. This is known as digit preference; it is a well-known phenomenon in frequency distributions of indurations collected in tuberculin surveys. Digit preference can distort estimates of prevalence and other statistical parameters. METHODS: We have developed a statistical model that combines smoothing by penalized likelihood and the transfer of counts from non-preferred to preferred digits, to obtain estimates of: 1) the smooth underlying distribution and 2) the amount of digit preference. RESULTS: To illustrate the validity of the model, it was applied to data from several countries. CONCLUSION: With the proposed model, digit preference can be quantified and frequency distributions of indurations can be corrected for it.


Assuntos
Interpretação Estatística de Dados , Modelos Estatísticos , Teste Tuberculínico/estatística & dados numéricos , Algoritmos , Viés , Comportamento de Escolha , Humanos , Funções Verossimilhança , Reprodutibilidade dos Testes
14.
Eur J Obstet Gynecol Reprod Biol ; 92(1): 91-6, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10986440

RESUMO

OBJECTIVE: To compare the outcome after intrauterine transfusion (IUT) between fetuses treated before and those treated after 32 weeks gestation. SETTING: National referral center for intrauterine treatment of red-cell alloimmunization in The Netherlands. STUDY DESIGN: Retrospective evaluation of an 11 year period, during which 209 fetuses were treated for alloimmune hemolytic disease with 609 red-cell IUTs. We compared fetal and neonatal outcome in three groups: fetuses only treated before 32 weeks gestation (group A, n=46), those treated both before and after 32 weeks (group B, n=117), and those where IUT was started at or after 32 weeks (group C, n=46). RESULTS: Survival rate was 48% in group A, 100% in group B, and 91% in group C. Moreover, fetuses in group A were hydropic significantly more often. Short-term perinatal loss rate after IUT was 3.4% in the 409 procedures performed before 32 weeks and 1.0% in the 200 procedures performed after 32 weeks gestation. CONCLUSION: Perinatal losses were much more common in fetuses only treated before 32 weeks gestation. Two procedure-related perinatal losses in 200 IUT after 32 weeks remain a matter of concern because of the good prospects of alternative extrauterine treatment.


Assuntos
Transfusão de Sangue Intrauterina , Eritroblastose Fetal/terapia , Isoimunização Rh/terapia , Transfusão de Sangue Intrauterina/efeitos adversos , Cesárea , Eritroblastose Fetal/mortalidade , Feminino , Morte Fetal , Idade Gestacional , Humanos , Mortalidade Infantil , Recém-Nascido , Gravidez , Terceiro Trimestre da Gravidez , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
15.
Clin Biomech (Bristol, Avon) ; 18(4): 296-302, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12689779

RESUMO

OBJECTIVE: To describe patterns of external rotation during humeral elevation, and to compare motion patterns.Design. Patterns of external rotation during forward flexion, scapular abduction and abduction in the frontal plane are described with P-spline curves with an approximately 95% confidence interval. BACKGROUND: External rotation of the humerus is an essential part of humeral elevation. Standard clinical assessment of external rotation provides insufficient information to describe external rotation patterns which may be essential for insight in shoulder disorders.Methods. The dominant and non-dominant arms of thirty subjects are measured, using a three-dimensional electromagnetic movement recording system. RESULTS: Overall group patterns demonstrate that humeral elevation in all planes is accompanied by about 55 degrees of external rotation, and each elevation plane has its own typical pattern. The dominant and non-dominant sides are comparable and can be combined. CONCLUSIONS: There are specific external rotation patterns for each elevation plane. Curves representing the approximately 95% confidence intervals make comparison between groups possible. This method can therefore possibly be used to study the external rotation patterns in groups with certain shoulder disorders to evaluate the results of before and after treatment. RELEVANCE: The method presented in this paper can be used to study external rotation patterns in healthy shoulders and in shoulders with a specific disorders to gain more insight, to define functional treatment, and to evaluate the results of treatment.


Assuntos
Úmero/fisiologia , Movimento/fisiologia , Escápula/fisiologia , Articulação do Ombro/fisiologia , Adulto , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Reprodutibilidade dos Testes , Rotação , Sensibilidade e Especificidade
16.
J Plast Reconstr Aesthet Surg ; 66(4): 543-50, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23369737

RESUMO

BACKGROUND: Tendon transfers are essential for reconstruction of hand function in tetraplegic patients. To transfer the extensor carpi radialis longus (ECRL), the extensor carpi radialis brevis (ECRB) has to be sufficiently strong. However, there is currently no reliable clinical test to individually analyse both muscles. In order to develop a reliable preoperative clinical test, the anatomy of the muscle (innervation) areas of ECRB, ECRL and brachio-radialis (BR) was examined. METHODS: In 20 arms, the ECRB, ECRL and BR were dissected and localised. Subsequently, muscle-innervation points were mapped and categorised. A novel method, computer-assisted surgical anatomy mapping (CASAM), was used to visualise muscle areas and innervation points in a computed arm with average dimensions. RESULTS: For both ECRL and ECRB a 100% area could be identified, a specific area in the computed average arm in which the muscle was present for all 20 arms. For the ECRL, this area was situated at 16% of the distance between the lateral epicondyle and the deltoid muscle insertion. The ECRB 100% area was 5 times bigger than that of the ECRL and was located at 40% of the distance between the lateral epicondyle and the radial styloid process. The ECRL and BR showed one to three innervation points, the ECRB one to four. In 47% of the cases, there was a combined nerve branch innervating both the ECRL and the ECRB. CONCLUSIONS: It is feasible to develop a preoperative test; the 100% areas can be used for needle electromyography (EMG) or local anaesthetic muscle injections.


Assuntos
Processamento de Imagem Assistida por Computador , Força Muscular , Músculo Esquelético/fisiologia , Transferência Tendinosa , Estudos de Viabilidade , Pé/inervação , Humanos , Contração Isométrica/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/inervação , Período Pré-Operatório
17.
J Dev Orig Health Dis ; 3(5): 315-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25102259

RESUMO

Maternal smoking during pregnancy and a low socioeconomic status (SES) lead to increased risks of adverse pregnancy outcome. Maternal education is often used as proxy for SES. We explored the programming of the insulin pathway genes IGF2 DMR (insulin growth factor 2 differentially methylated region), IGF2R (insulin growth factor 2 receptor) and INSIGF [the overlapping region of IGF2 and insulin (INS)] in the child through any periconception maternal smoking and education level. In 120 children at 17 months of age, methylation of DNA derived from white blood cells was measured. Periconception smoking and low education were independently associated with INSIGF methylation and showed a relative increase in methylation of +1.3%; P = 0.043 and +1.6%; P = 0.021. Smoking and low education showed an additive effect on INSIGF methylation (+2.8%; P = 0.011). There were no associations with IGF2 DMR and IGF2R methylation. Our data suggest that periconception maternal smoking and low education are associated with epigenetic marks on INSIGF in the very young child, this warrants further study in additional populations.


Assuntos
Metilação de DNA , Proteínas Mutantes Quiméricas/genética , Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Adulto , Escolaridade , Epigênese Genética , Feminino , Homologia de Genes , Humanos , Lactente , Insulina/genética , Insulina/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Modelos Lineares , Masculino , Proteínas Mutantes Quiméricas/metabolismo , Gravidez , Receptor IGF Tipo 2/genética , Receptor IGF Tipo 2/metabolismo , Fatores Socioeconômicos
18.
Int J Obes (Lond) ; 31(11): 1671-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17471294

RESUMO

OBJECTIVE: The objective of this study was to systematically evaluate the molecular basis of the association between visceral fat mass and plasma plasminogen activator inhibitor-1 (PAI-1) levels in man. DESIGN: A comprehensive approach comprising observational, in vitro, and human intervention studies. MEASUREMENTS AND RESULTS: We confirmed an exclusive relationship between visceral fat and plasma PAI-1 levels (r=0.79, P<0.001) and corroborated preferential PAI-1 release from adipose tissue explants. Yet, messenger RNA analysis and in vivo measurement of PAI-1 release from visceral fat (AV-differences over the omentum) not only excluded visceral adipose tissue as a relevant source of circulating PAI-1, but also excluded visceral fat as a significant source of proinflammatory mediators such as tumor necrosis factor-alpha, IL-1 or transforming growth factor-beta that could induce PAI-1 expression in tissues other than visceral fat. Short-term interventions with acipimox and growth hormone (GH) as well as statistical evaluation excluded free fatty acids and GH as metabolic links. Further analysis of the metabolic data in a stepwise regression model indicated that plasma PAI-1 levels and visceral fat rather are co-correlates that both relate to impaired lipid handling. CONCLUSION: Our PAI-1 studies show that visceral fat mass and plasma PAI-1 levels are co-correlated rather than causatively related, with lipid load as common denominator.


Assuntos
Gordura Intra-Abdominal/metabolismo , Inibidor 1 de Ativador de Plasminogênio/sangue , Adiposidade/fisiologia , Adulto , Antropometria , Citocinas/biossíntese , Feminino , Hormônio do Crescimento Humano/deficiência , Humanos , Mediadores da Inflamação/metabolismo , Gordura Intra-Abdominal/anatomia & histologia , Gordura Intra-Abdominal/patologia , Metabolismo dos Lipídeos , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/patologia , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Mensageiro/genética , Técnicas de Cultura de Tecidos , Fator de Necrose Tumoral alfa/biossíntese
19.
J Pathol ; 212(3): 269-77, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17471469

RESUMO

Total mesorectal excision (TME) is the standard treatment for rectal cancer, while transanal endoscopic microsurgery (TEM) is a recently introduced surgical approach for the treatment of rectal adenomas. Incorrect preoperative staging before TEM is a problem. To identify genetic changes that might correlate with tumour stage and could lead to optimized treatment selection we performed a genome-wide chromosomal instability search in a homogeneous, clinical cohort of rectal tumours. 78 rectal tumours during different clinical stages were analysed with 10K single nucleotide polymorphism (SNP) arrays. Logistic regression was performed to build a quantitative model of specific chromosomal aberrations. Overall, most cases (95%) had one or more chromosomal aberrations. We observed a clear correlation between the total number of aberrations and the different tumour stages. Specifically, the chromosomal events: gain of 8q22-24, 13q and 20q, and loss of 17p and 18q12-22, were far more abundant in carcinoma than in adenoma. In adenoma fractions from cases with a carcinoma (infiltrating at least in the submucosa), twice the amount of such 'malignant aberrations' was observed, compared to pure adenomas. Furthermore, combined aberrations such as gain of 13q and loss of 18q were only found in adenomatous fractions of carcinomas and not in benign lesions. Based on these five genomic events associated with carcinoma, a clear distinction between adenoma and carcinoma tissue could be made. These data should be validated further in order that they may be used in preoperative staging of rectal tumours.


Assuntos
Adenoma/patologia , Carcinoma/patologia , Instabilidade Cromossômica , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Neoplasias Retais/genética , Neoplasias Retais/patologia , Adenoma/genética , Análise de Variância , Carcinoma/genética , Diagnóstico Diferencial , Genoma , Humanos , Modelos Logísticos , Perda de Heterozigosidade , Estadiamento de Neoplasias
20.
J Pathol ; 208(4): 507-17, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16435282

RESUMO

To determine whether CCL2 mRNA expression is beneficial or detrimental for cervical cancer patients, the association between the expression of this molecule by cervical tumour cells, the number of tumour-associated macrophages, and clinicopathological parameters such as recurrence, relapse-free survival, and overall patient survival was investigated. In cervical cancer samples from 93 untreated cervical cancer patients, the CCL2 mRNA expression level was quantified using RNA in situ hybridization and verified using real-time quantitative RT-PCR. The number of tumour-associated macrophages was determined using immunohistochemistry. Furthermore, the study investigated whether lack of CCL2 expression was due to genetic alterations near the 17q11.2 (CCL2 genomic) region. CCL2 mRNA expression by cervical tumour cells was associated with the number of tumour-associated macrophages (p < 0.001). Lack of CCL2 mRNA expression (15 samples; 16%) was associated with increased cumulative relapse-free survival (log rank test, p = 0.030), increased cumulative overall survival (log rank test, p = 0.024), less post-operative surgery, reduced local and distant recurrence, reduced vascular invasion, and smaller tumour size (<40 mm). The absence of CCL2 mRNA expression corresponded with loss of heterozygosity (LOH) at 17q11.2 in five of six samples. The increased cumulative relapse-free survival and cumulative overall survival of cervical cancer patients lacking tumour cell-associated CCL2 mRNA suggest that the tumour-associated macrophages support tumour progression, presumably by promoting angiogenesis and production of growth factors.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma/genética , Quimiocina CCL2/genética , Recidiva Local de Neoplasia/genética , RNA Mensageiro/análise , Neoplasias do Colo do Útero/genética , Carcinoma/mortalidade , Carcinoma/patologia , Intervalo Livre de Doença , Feminino , Expressão Gênica , Humanos , Hibridização In Situ , Perda de Heterozigosidade , Macrófagos/patologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
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