Publications by authors named "Diego Marin"

40 Publications

The "mosaic" embryo: misconceptions and misinterpretations in preimplantation genetic testing for aneuploidy.

Fertil Steril 2021 Jul 22. Epub 2021 Jul 22.

Genomic Prediction Inc., North Brunswick, New Jersey.

Preimplantation genetic testing for aneuploidy (PGT-A) remains one of the most controversial topics in reproductive medicine. With more than 40% of in vitro fertilization cycles in the United States reportedly involving PGT, both those in favor of and those opposed to PGT-A have significant interest in the efficacy of PGT-A. Ongoing issues include what patient population, if any, benefits from PGT-A, the true frequency of chromosomal mosaicism, whether embryonic aneuploidies self-correct, and how practitioners manage embryos designated as "mosaic." This review addresses several misconceptions and misinterpretations of data surrounding the genetic analysis and prediction of mosaicism in the preimplantation embryo.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fertnstert.2021.06.027DOI Listing
July 2021

embryo production in buffaloes: from the laboratory to the farm.

Anim Reprod 2019 Oct 23;16(2):260-266. Epub 2019 Oct 23.

Instituto de Ciências Biológicas, Universidade Federal do Pará (UFPA), Belém, Pará, Brazil.

Transvaginal follicular aspiration technique together with embryo production are the biotechnological alternatives currently available to support genetic improvement breeding programs in buffalo species. However, aspects related to animal management, lack of knowledge of the metabolic needs and biochemical peculiarities of gametes and embryos, as well as the reproductive physiology characteristics have hampered progress in the results. Despite the low availability of good quality oocytes collected after OPU in donors as a physiological characteristic of buffalo species, high rates of oocyte maturation, modest embryo cleavage, blastocyst production and pregnancy rates after transvaginal embryo transfer in recipients could be obtained in buffalo embryo production programs. The results of implementing an embryo production program in buffaloes in the northern region of Pará state, Brazil, and results published by other groups demonstrate the feasibility of implementing this biotechnology in the routine of breeding programs. Nevertheless, in order to achieve better and consistent results, it is necessary to deepen the knowledge on the peculiarities of reproductive biology in this specie. Selection of donor animals based on ovarian size and ovarian follicular reserve and on the rate of blastocyst production is presented as an effective alternative to increase the efficiency of the embryo production technique applied to the buffalo species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21451/1984-3143-AR2018-0135DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7673586PMC
October 2019

Allele-Specific Chromosome Removal after Cas9 Cleavage in Human Embryos.

Cell 2020 12 29;183(6):1650-1664.e15. Epub 2020 Oct 29.

Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University, New York, NY 10032, USA; Columbia University Stem Cell Initiative, New York, NY 10032, USA; Department of Obstetrics and Gynecology, Columbia University, New York, NY 10032, USA. Electronic address:

Correction of disease-causing mutations in human embryos holds the potential to reduce the burden of inherited genetic disorders and improve fertility treatments for couples with disease-causing mutations in lieu of embryo selection. Here, we evaluate repair outcomes of a Cas9-induced double-strand break (DSB) introduced on the paternal chromosome at the EYS locus, which carries a frameshift mutation causing blindness. We show that the most common repair outcome is microhomology-mediated end joining, which occurs during the first cell cycle in the zygote, leading to embryos with non-mosaic restoration of the reading frame. Notably, about half of the breaks remain unrepaired, resulting in an undetectable paternal allele and, after mitosis, loss of one or both chromosomal arms. Correspondingly, Cas9 off-target cleavage results in chromosomal losses and hemizygous indels because of cleavage of both alleles. These results demonstrate the ability to manipulate chromosome content and reveal significant challenges for mutation correction in human embryos.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cell.2020.10.025DOI Listing
December 2020

Preimplantation genetic testing for aneuploidy: A review of published blastocyst reanalysis concordance data.

Prenat Diagn 2021 04 4;41(5):545-553. Epub 2020 Oct 4.

Genomic Prediction, North Brunswick, New Jersey, USA.

Preimplantation genetic testing for aneuploidy (PGT-A) reduces miscarriage risk, increases the success of IVF, shortens time to pregnancy, and reduces multiple gestation rates without compromising outcomes. The progression of PGT-A has included common application of next-generation sequencing (NGS) from single nucleotide polymorphism microarray, quantitative real-time PCR, and array comparative hybridization platforms of analysis. Additional putative advances in PGT-A capability include classifying embryos as mosaic and predicting the presence of segmental imbalance. A critical component in the process of technical validation of these advancements involves evaluation of concordance between reanalysis results and initial testing results. While many independent studies have investigated the concordance of results obtained from the remaining embryo with the original PGT-A diagnosis, compilation and systematic analysis of published data has not been performed. Here, we review results from 26 primary research articles describing concordance in 1271 human blastocysts from 2260 pairwise comparisons. Results illustrate significantly higher discordance from PGT-A methods which utilize NGS and include prediction of mosaicism or segmental imbalance. These results suggest caution when considering new iterations PGT-A.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pd.5828DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8259107PMC
April 2021

Modulation of phosphatidylinositol 3-kinase activity during oocyte maturation increases the production of bovine blastocysts.

Zygote 2020 Aug 3:1-6. Epub 2020 Aug 3.

Laboratório de Reprodução e Melhoramento Genético Animal, Centro de Ciências e Tecnologias Agropecuárias, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, CEP: 28013-602. Campos dos Goytacazes, Rio de Janeiro, Brazil.

This study aimed to evaluate the effect of regulating phosphatidylinositol 3-kinase (PI3K) activity on the kinetics of oocyte nuclear maturation and the blastocyst rate. To evaluate oocyte viability, nuclear maturation rate and in vitro embryo production, cumulus-oocyte complexes (COCs) were maintained for 0, 10 min, 6 h or 22 h in TCM 199 medium supplemented with 20 nM wortmannin, an inhibitor of PI3K. After each period, COCs were transferred to the same medium without wortmannin and kept under the same conditions until completion of 22 h of in vitro maturation (IVM). To evaluate the effect of time on progression of nuclear maturation, COCs cultivated with 20 nM wortmannin was maintained for 22, 28 or 34 h of IVM. To determine the effect of wortmannin on the activity of maturation-promoting factor (MPF), COCs were kept under IVM conditions in the presence of the inhibitor for 0, 1, 3, 6, or 8 h. Exposure of COCs to wortmannin decreased (P < 0.05) the percentage of oocytes that reached metaphase II (MII) up to 22 h, MPF activity and reduced PI3K activity by 30%. However, after 28 and 34 h, 70% of oocytes reached the MII stage in the presence of inhibitor Moreover, COCs matured in the presence of wortmannin showed an increase (P < 0.05) in the blastocyst rate. These findings suggested that the regulation of the PI3K activity during IVM of bovine COCs interfered with the meiotic progression due to control of MPF activity, positively affecting the blastocyst rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1017/S0967199420000209DOI Listing
August 2020

Mitochondrial DNA content is not predictive of reproductive competence in euploid blastocysts.

Reprod Biomed Online 2020 Aug 14;41(2):183-190. Epub 2020 May 14.

Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, 310 Cedar street, LSOG 304B, New Haven CT, 06525, USA; IVIRMA New Jersey, 140 Allen Road, Basking Ridge NJ, 07920, USA. Electronic address:

Research Question: Does mitochondrial DNA (mtDNA) copy number predict the reproductive potential of euploid human blastocysts?

Design: To investigate whether the amount of mtDNA in trophectoderm biopsies correlates with IVF outcome, euploid human blastocysts (n = 615) used in single embryo transfer were analysed. Furthermore, to determine whether mtDNA content is predictive of reproductive outcome within a given cohort, paired sibling embryos (n = 78) transferred in two consecutive cycles carried out in the same patient (in which one cycle failed to result in implantation and the other cycle resulted in sustained implantation) were studied. Targeted amplification followed by quantitative real-time polymerase chain reaction for two mitochondrial loci (16S and MajArc) relative to a multicopy nuclear genome locus (AluYb8) were carried out to determine relative mtDNA copy number.

Results: Sustained implantation was not associated with relative mtDNA copy number (P = 0.78), and there was no threshold value above or below which ongoing implantation was more or less likely. No correlation was observed between maternal age and relative mtDNA copy number (P = 0.39). In addition, no association was found between relative mtDNA levels of sibling embryos and ensuing implantation and delivery rates in women who underwent a successful single embryo transfer before or after a failed transfer using embryos derived from the same cohort of oocytes (P = 0.70).

Conclusions: In trophectoderm samples, mitochondrial DNA copy number analysis was not found to be predictive of euploid human embryo reproductive competence. These data do not support the use of mitochondrial DNA copy number in clinical decision making when selecting which embryo to transfer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rbmo.2020.04.011DOI Listing
August 2020

Preimplantation Genetic Testing for Polygenic Disease Relative Risk Reduction: Evaluation of Genomic Index Performance in 11,883 Adult Sibling Pairs.

Genes (Basel) 2020 06 12;11(6). Epub 2020 Jun 12.

Genomic Prediction Inc., 675 US Highway One, North Brunswick, NJ 08902, USA.

Preimplantation genetic testing for polygenic disease risk (PGT-P) represents a new tool to aid in embryo selection. Previous studies demonstrated the ability to obtain necessary genotypes in the embryo with accuracy equivalent to in adults. When applied to select adult siblings with known type I diabetes status, a reduction in disease incidence of 45-72% compared to random selection was achieved. This study extends analysis to 11,883 sibling pairs to evaluate clinical utility of embryo selection with PGT-P. Results demonstrate simultaneous relative risk reduction of all diseases tested in parallel, which included diabetes, cancer, and heart disease, and indicate applicability beyond patients with a known family history of disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/genes11060648DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7349610PMC
June 2020

Comparative economic analysis of soil sampling methods used in precision agriculture.

An Acad Bras Cienc 2020 1;92 Suppl 1:e20190277. Epub 2020 Jun 1.

Departamento de Engenharia Agrícola, Universidade Federal de Lavras/UFLA, Lavras, MG, Brazil.

Precision agriculture is an alternative for reducing costs. This study evaluated and economically compared three sampling methods used in precision agriculture with respect to the acquisition of inputs and machines and equipment. The sampling methods used were zone management by elevation (ZME), grid sampling (GS) and sampling guided by apparent electrical conductivity of the soil (OS). Soil samples for the ZME were collected after the definition of zones according to the elevations of the plots. The sample mesh was in a georeferenced mesh of 100 x 100 m. The targeted sampling was performed after a ground proximity sensor was used to identify the apparent electrical conductivity of the soil to define the management areas. From the results of the laboratory tests, the application costs were calculated for lime, phosphorus, potassium and nitrogen to allow a comparison between the methods, volumes and costs. This approach considered the costs of depreciation, insurance, interest, operating costs, labor, maintenance and fuel. With this study, it was possible to compare the volumes of the recommended fertilizers and estimate the overall economic cost of using the technology via sensor. Taking the GS as a reference, the ZME presented as the best alternative compared to other methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1590/0001-3765202020190277DOI Listing
June 2020

PREIMPLANTATION GENETIC TESTING: Preimplantation genetic testing for polygenic disease risk.

Reproduction 2020 Nov;160(5):A13-A17

Genomic Prediction Inc., North Brunswick, New Jersey, USA.

Since its introduction to clinical practice, preimplantation genetic testing (PGT) has become a standard of care for couples at risk of having children with monogenic disease and for chromosomal aneuploidy to improve outcomes for patients with infertility. The primary objective of PGT is to reduce the risk of miscarriage and genetic disease and to improve the success of infertility treatment with the delivery of a healthy child. Until recently, the application of PGT to more common but complex polygenic disease was not possible, as the genetic contribution to polygenic disease has been difficult to determine, and the concept of embryo selection across multiple genetic loci has been difficult to comprehend. Several achievements, including the ability to obtain accurate, genome-wide genotypes of the human embryo and the development of population-level biobanks, have now made PGT for polygenic disease risk applicable in clinical practice. With the rapid advances in embryonic polygenic risk scoring, diverse considerations beyond technical capability have been introduced.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1530/REP-20-0071DOI Listing
November 2020

Cumulus cells have longer telomeres than leukocytes in reproductive-age women.

Fertil Steril 2020 01 6;113(1):217-223. Epub 2019 Oct 6.

IVIRMA Rome, Roma, Italy.

Objective: To investigate whether telomere length (TL) in granulosa cells (GC) or cumulus cells (CC) correlates with TL in leukocytes (L).

Design: Prospective noninterventional study.

Setting: Private assisted reproductive technology center.

Patient(s): Thirty-five egg donors were included in the study.

Interventions(s): None.

Main Outcome Measure(s): Average relative leukocyte telomere length (LTL), cumulus cell telomere length (CCTL), and granulosa cell telomere length (GCTL) measurements from each study subject.

Result(s): Participants had a mean age of 25.43 ± 4.57 years, antimüllerian hormone level of 1.90 ± 0.92 ng/mL, antral follicle count of 23.29 ± 5.11, and the mean number of mature oocytes retrieved was 23.29 ± 9.13. No significant association between these variables and GCTL, CCTL, or LTL was found. In addition, no correlation was observed between TL measurements of L vs. CC, L vs. GC, or CC vs. GC. Interestingly, CCTL was significantly higher than LTL (1.54-fold), although no significant differences were found between GCTL vs. CCTL or GCTL vs. LTL.

Conclusion(s): CC from mature follicles have significantly longer telomeres than L, suggesting that the follicular environment could possess different mechanisms to cope against telomere shortening compared with other somatic tissues. Furthermore, these data do not support the utility of telomere DNA measurement in L as an estimate of TL in follicular cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fertnstert.2019.08.089DOI Listing
January 2020

Nitric oxide impacts bovine sperm capacitation in a cGMP-dependent and cGMP-independent manner.

Reprod Domest Anim 2019 Dec 4;54(12):1612-1620. Epub 2019 Oct 4.

Laboratório de Reprodução e Melhoramento Genético Animal, Centro de Ciências e Tecnologias Agropecuárias (CCTA), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Brazil.

We aimed to elucidate whether NO acts in in vitro sperm capacitation in bovine via cGMP/PKG1 pathway. For this, cryopreserved bovine sperm were capacitated in vitro with 20 µg/ml heparin (Control) plus treatments: 1 mM L-arginine (L-arg, NO precursor), 50 µM Rp-8-Bromo-β-phenyl-1,N -ethenoguanosine-3',5'-cyclic monophosphorothioate (Rp-8-Br-cGMPS, selective inhibitor of the binding site for cGMP in PKG1), 1 mM 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO, NO scavenger), and the combinations of L-arg + RP-8-Br-cGMPS and L-arg + PTIO. Sperm motility and vigour were determined by phase-contrast microscopy, capacitation status by chlortetracycline staining, and the intracellular concentration of cGMP was measured by ELISA. Data were subjected to analysis of variance and means compared with SNK test at 5% probability. Motility and vigour were lower in sperm treated with PTIO when compared to Control and other treatments (p < .05). The L-arg treatment showed the highest percentage of capacitated sperm when compared to the Control and other treatments (Rp-8-Br-cGMPS, L-arg + Rp-8-Br-cGMPS and PTIO) (69.8 ± 3.4%, 51.2 ± 3.0, 51.1 ± 2.1, 51.2 ± 3.0 and 45.5 ± 2.7, respectively) (p < .05). The capacitation ratio (%) was lower in treatments with Rp-8-Br-cGMPS, L-arg + Rp-8-Br-cGMPS and PTIO, respectively (p < .05). Lastly, cGMP concentration (pmol/ml) was lower in PTIO and L-arg + PTIO (1.3 ± 0.3 and 1.6 ± 0.4) and was higher in Rp-8-Br-cGMPS and L-arg + Rp-8-Br-cGMPS (3.7 ± 0.4 and 4.0 ± 0.5) treatments. We showed that during in vitro capacitation of cattle: (a) NO influences sperm motility and vigour; (b) NO is associated with cGMP synthesis through two independent pathways and (c) the cGMP/PKG1 pathway has a partial role in sperm capacitation and does not involve the L-arg/NO.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/rda.13570DOI Listing
December 2019

New Frontiers in IVF: mtDNA and autologous germline mitochondrial energy transfer.

Reprod Biol Endocrinol 2019 Jul 12;17(1):55. Epub 2019 Jul 12.

Department of Obstetrics and Gynecology, Lincoln Medical and Mental Health Center, Bronx, New York, USA.

Many infertility specialists support the existence of a relationship between the levels of mitochondrial DNA and the quality of the blastocysts. Despite the extensive use of pre-implantation genetic testing for aneuploidy, a significant percentage of euploid embryos do not implant even though the endometrium is normal. Mitochondrial DNA may be used as a new test in evaluating embryonic vitality.Ovarian aging leads to a decrease in the quantity and quality of oocytes and aged oocytes have a reduced number of mitochondria. Mitochondria are the energy factories of the cells and their lacked could leads to lower fertilization rates and poor embryonic development. Various strategies have been tested to increase the mitochondria quantity and thus improve the quality of oocytes used in in vitro fertilization. Results of ovarian rejuvenation techniques such as autologous mitochondrial transplantation have been controversial. In this review, we describe the state of the art concerning the use of mitochondrial DNA and autologous mitochondrial transplantation as new possibilities to increase success in vitro fertilization.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12958-019-0501-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6626406PMC
July 2019

In vitro fertilization and infertility do not cause a significant alteration in placental gene expression at the end of the first trimester.

Fertil Steril 2019 03 5;111(3):463-464. Epub 2019 Feb 5.

IVIRMA New Jersey, Basking Ridge, New Jersey; and Yale School of Medicine, New Haven, Connecticut.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fertnstert.2018.12.006DOI Listing
March 2019

DNA methylation-based age prediction and telomere length in white blood cells and cumulus cells of infertile women with normal or poor response to ovarian stimulation.

Aging (Albany NY) 2018 12;10(12):3761-3773

IVIRMA New Jersey, Basking Ridge, NJ 07920, USA.

An algorithm assessing the methylation levels of 353 informative CpG sites in the human genome permits accurate prediction of the chronologic age of a subject. Interestingly, when there is discrepancy between the predicted age and chronologic age (age acceleration or "AgeAccel"), patients are at risk for morbidity and mortality. Identification of infertile patients at risk for accelerated reproductive senescence may permit preventative action. This study aimed to assess the accuracy of the "epigenetic clock" concept in reproductive age women undergoing fertility treatment by applying the age prediction algorithm in peripheral (white blood cells [WBCs]) and follicular somatic cells (cumulus cells [CCs]), and to identify whether women with premature reproductive aging (diminished ovarian reserve) were at risk of AgeAccel in their age prediction. Results indicated that the epigenetic algorithm accurately predicts age when applied to WBCs but not to CCs. The age prediction of CCs was substantially younger than chronologic age regardless of the patient's age or response to stimulation. In addition, telomeres of CCs were significantly longer than that of WBCs. Our findings suggest that CCs do not demonstrate changes in methylome-predicted age or telomere-length in association with increasing female age or ovarian response to stimulation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/aging.101670DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326671PMC
December 2018

Conventional versus minimal ovarian stimulation: an intra-patient comparison of ovarian response in poor-responder women according to Bologna Criteria.

Reprod Biomed Online 2018 Oct 23;37(4):434-441. Epub 2018 Aug 23.

IVI-RMA Global, Plaza Policía Local, Valencia3. 46015, Spain.

Research Question: Is minimal ovarian stimulation (MOS) as effective as conventional ovarian stimulation (COS) in ovarian response and embryo quality in the same 46 poor-responder patients according to the Bologna criteria?

Design: An intra-patient comparison of patients undergoing both protocols. Ovaries were stimulated with either a gonadotrophin-releasing hormone antagonist protocol and a combination of recombinant FSH and highly purified human menotrophin (HP-HMG) daily (COS), or with the use of clomiphene citrate 50 mg daily and 150 IU of HP-HMG or recombinant FSH every other day from simulation day 4 (MOS).

Results: After MOS, significantly more good-quality embryos (1.0 ± 1.2 versus 0.3 ± 0.6) (P = 0.002), oocytes (3.2 ± 1.9 versus 2.0 ± 1.8) (P = 0.002), and mature (metaphase II) oocytes (2.6 ± 1.7 versus 1.6 ± 1.7) (P = 0.001) were obtained. In COS cycles, a significantly higher total gonadotrophin dose was needed per good-quality embryo (+2194 IU; 95% CI 618 to 3170).

Conclusions: In poor responder patients, MOS is a good alternative when COS has failed, or even as a first-line treatment. It offered a significantly greater number of good-quality embryos as well as a higher number of oocytes, using significantly lower doses of gonadotrophins per oocyte and embryo obtained.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rbmo.2018.07.007DOI Listing
October 2018

Celiac disease is not more prevalent in patients undergoing in vitro fertilization and does not affect reproductive outcomes with or without treatment: a large prospective cohort study.

Fertil Steril 2018 08;110(3):437-442

Reproductive Medicine Associates of New Jersey, Basking Ridge, New Jersey; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.

Objective: To study the prevalence of celiac disease in the infertile population undergoing in vitro fertilization (IVF) and assess outcomes.

Design: Prospective cohort study.

Setting: A single infertility center from January 2016 to March 2017.

Patient(s): Women 18-45 years of age participating in IVF.

Intervention(s): Patients had serum tissue transglutaminase (tTG) and endomysial (EMA) IgA testing to screen for celiac disease and completed a 10-question "yes or no" survey to assess their medical history, previous testing, dietary habits, and pertinent symptoms.

Main Outcome Measure(s): IVF cycle outcomes were compared between seronegative and seropositive patients.

Result(s): Of 1,000 patients enrolled, 995 completed serologic screening and 968 underwent oocyte retrieval. Eighteen patients screened positive for both tTG and EMA (1.8%) and 10 additional patients (1.0%) screened positive for one of the two antibodies. The number of mature oocytes retrieved, fertilization rates, and blastulation rates were equivalent between seronegative and seropositive patients. There were 987 patients who completed the questionnaire (98.7%), and 84 reported being gluten free (8.5%). Those who reported being gluten free were no more likely to be antibody positive than the general population. Furthermore, a low-gluten diet was not associated with markers of ovarian reserve, oocytes retrieved, fertilization, blastulation, sustained implantation and pregnancy loss rates.

Conclusion(s): The prevalence of seropositive celiac disease was consistent with that of the general population (2.8%). Patients who were seropositive for celiac disease-related antibodies had outcomes equivalent to seronegative patients, and patients with a gluten-free diet did not have improved outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fertnstert.2018.03.030DOI Listing
August 2018

Household survey data of adoption of improved varieties and management practices in rice production, Ecuador.

Data Brief 2018 Jun 10;18:1252-1256. Epub 2018 Apr 10.

International Centre for Tropical Agriculture (CIAT), Cali, Colombia.

This article provides a description of an agricultural household survey data of rice growers collected in Ecuador between October 2014 and March 2015. The household survey was implemented using a structured questionnaire administered among 1028 households in the main rice production areas of Ecuador (i.e. Guayas, Los Rios, Manabi, and El Oro provinces). Information collected was provided by household heads (male or female) and included household and plot level data. The survey information includes household socio-demographic characteristics (e.g. age, education, gender, main economic activity, etc.), farm characteristics (e.g. farm land size, assets ownership, other crops planted, etc.), rice management practices (e.g. variety and input use, production costs, etc.), and rice production and utilization (e.g. yields, prices, sales, etc.). Additional socio-economic context variables were also recorded such as government subsidies to rice production, participation in rural organizations, and food security related questions. The dataset contains a total of 6288 variables among numeric, categorical and string variables. The dataset is shared publicly on the Harvard dataverse site and provide access to questionnaires, the complete data and a brief report.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dib.2018.04.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5996945PMC
June 2018

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I.

J Vis Exp 2018 Apr 10(134). Epub 2018 Apr 10.

Department of Genetics, Rutgers, The State University of New Jersey;

Embryonic aneuploidy is the major genetic cause of infertility in humans. Most of these events originate during female meiosis, and albeit positively correlated with maternal age, age alone is not always predictive of the risk of generating an aneuploid embryo. Therefore, gene variants might account for incorrect chromosome segregation during oogenesis. Given that access to human oocytes is limited for research purposes, a series of assays were developed to study human gene function during meiosis I using mouse oocytes. First, messenger RNA (mRNA) of the gene and gene variant of interest are microinjected into prophase I-arrested mouse oocytes. After allowing time for expression, oocytes are synchronously released into meiotic maturation to complete meiosis I. By tagging the mRNA with a sequence of a fluorescent reporter, such as green fluorescent protein (Gfp), the localization of the human protein can be assessed in addition to the phenotypic alterations. For example, gain or loss of function can be investigated by establishing experimental conditions that challenge the gene product to fix meiotic errors. Although this system is advantageous in investigating human protein function during oogenesis, adequate interpretation of results should be undertaken given that protein expression is not at endogenous levels and, unless controlled for (i.e. knocked out or down), murine homologs are also present in the system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3791/57442DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5933469PMC
April 2018

Extracellular vesicles: a promising tool for assessment of embryonic competence.

Curr Opin Obstet Gynecol 2018 06;30(3):171-178

IVI-RMA New Jersey, Basking Ridge, New Jersey.

Purpose Of Review: Extracellular vesicles have recently emerged as a promising field of research due to their pivotal roles in intercellular communication and potential to serve as biomarkers. This review focuses on extracellular vesicles secreted by the human preimplantation embryo. The most recent findings on embryo-derived extracellular vesicles are described and discussed, as well as current technical challenges to study them.

Recent Findings: So far, only a few studies have addressed extracellular vesicles of embryonic origin and explored their potential as biomarkers for embryo selection. Two main hypotheses have driven interest in studying extracellular vesicles in IVF embryo-conditioned culture media. On the one hand, the potential roles of extracellular vesicles in mediating the embryo-endometrial crosstalk for proper implantation. On the other hand, the profile of secreted extracellular vesicles as an indicator of embryonic fitness irrespective of any involvement or communication with the endometrium. Embryo-derived extracellular vesicles have already been investigated to design diagnostic tests for embryo viability, however with small sample sizes or without extensive technology validation.

Summary: Extracellular vesicles offer indeed a novel means to assess embryonic fitness. Further validation studies, technology development and more complex study designs are certainly required to implement the profiling of embryonic extracellular vesicles as a diagnostic test for embryo selection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/GCO.0000000000000458DOI Listing
June 2018

Validation of a targeted next generation sequencing-based comprehensive chromosome screening platform for detection of triploidy in human blastocysts.

Reprod Biomed Online 2018 Apr 2;36(4):388-395. Epub 2018 Jan 2.

Rutgers, The State University of New Jersey, Department of Genetics, Piscataway, NJ, USA.

Triploidy accounts for ~2% of natural pregnancies and 15% of cytogenetically abnormal miscarriages. This study aimed to validate triploidy detection in human blastocysts, its frequency and parental origin using genotyping data generated in parallel with chromosome copy number analysis by a targeted next generation sequencing (tNGS)-based comprehensive chromosome screening platform. Phase 1: diploid and triploid control samples were blinded, sequenced by tNGS and karyotype predictions compared for accuracy. Phase 2: tNGS was used to calculate the frequency of triploidy in 18,791 human blastocysts from trophectoderm (TE) biopsies. Phase 3: parental origin of the inherited extra alleles was evaluated by sequencing parental gDNA to validate triploidy predictions from Phase 2. All karyotypes and ploidy in controls from Phase 1 were correctly predicted by two independent methods. A blastocyst triploidy frequency of 0.474% (89/18,791) was observed in Phase 2 of the study. Finally, five suspected triploid blastocysts with parental DNA available were confirmed to be triploid and of maternal origin. tNGS provides higher sequencing depth in contrast to other contemporary NGS platforms, allowing for accurate single nucleotide polymorphism calling and accurate detection of triploidy in TE biopsies. Triploidy in intracytoplasmic sperm injection-derived blastocysts is rare and mostly of maternal origin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rbmo.2017.12.015DOI Listing
April 2018

A tool for automated diabetic retinopathy pre-screening based on retinal image computer analysis.

Comput Biol Med 2017 09 8;88:100-109. Epub 2017 Jul 8.

Department of Electronic, Computer Science and Automatic Engineering, University of Huelva, Spain.

Aim: This paper presents a methodology and first results of an automatic detection system of first signs of Diabetic Retinopathy (DR) in fundus images, developed for the Health Ministry of the Andalusian Regional Government (Spain).

Material And Methods: The system detects the presence of microaneurysms and haemorrhages in retinography by means of techniques of digital image processing and supervised classification. Evaluation was conducted on 1058 images of 529 diabetic patients at risk of presenting evidence of DR (an image of each eye is provided). To this end, a ground-truth diagnosis was created based on gradations performed by 3 independent ophthalmology specialists.

Results: The comparison between the diagnosis provided by the system and the reference clinical diagnosis shows that the system can work at a level of sensitivity that is similar to that achieved by experts (0.9380 sensitivity per patient against 0.9416 sensitivity of several specialists). False negatives have proven to be mild cases. Moreover, while the specificity of the system is significantly lower than that of human graders (0.5098), it is high enough to screen more than half of the patients unaffected by the disease.

Conclusion: Results are promising in integrating this system in DR screening programmes. At an early stage, the system could act as a pre-screening system, by screening healthy patients (with no obvious signs of DR) and identifying only those presenting signs of the disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.compbiomed.2017.07.007DOI Listing
September 2017

Comprehensive chromosome screening and gene expression analysis from the same biopsy in human preimplantation embryos.

Mol Hum Reprod 2017 05;23(5):330-338

Reproductive Medicine Associates of New Jersey, 140 Allen Road, Basking Ridge, NJ 07920, USA.

Study Question: Can simultaneous comprehensive chromosome screening (CCS) and gene expression analysis be performed on the same biopsy of preimplantation human embryos?

Summary Answer: For the first time, CCS and reliable gene expression analysis have been performed on the same human preimplantation embryo biopsy.

What Is Known Already: A single trophectoderm (TE) biopsy is routinely used for many IVF programs offering CCS for selection of only chromosomally normal embryos for transfer. Although the gene expression profiling of human preimplantation embryos has been described, to date no protocol allows for simultaneous CCS and gene expression profiling from a single TE biopsy.

Study Design, Size And Duration: This is a proof of concept and validation study structured in two phases. In Phase 1, cell lines were subjected to a novel protocol for combined CCS and gene expression analysis so as to validate the accuracy and reliability of the proposed protocol. In Phase 2, 20 donated human blastocysts were biopsied and processed with the proposed protocol in order to obtain an accurate CCS result and characterize their gene expression profiles using the same starting material.

Participants/materials, Setting And Method: A novel protocol coupling quantitative real-time PCR-based CCS and gene expression analysis using RT-PCR was designed for this study. Phase 1: six-cell aliquots of well-characterized fibroblast cell lines (GM00323, 46,XY and GM04435, 48,XY,+16,+21) were subjected to the proposed protocol. CCS results were compared with the known karyotypes for consistency, and gene expression levels were compared with levels of purified RNA from same cell lines for validation of reliable gene expression profiling. Phase 2: four biopsies were performed on 20 frozen human blastocysts previously diagnosed as trisomy 21 (10 embryos) and monosomy 21 (10 embryos) by CCS. All samples were processed with the proposed protocol and re-evaluated for concordance with the original CCS result. Their gene expression profiles were characterized and differential gene expression among embryos and early embryonic cell lineages was also evaluated.

Main Results And The Role Of Chance: CCS results from cell lines showed 100% consistency with their known karyotypes. ΔΔCt values of differential gene expression of four selected target genes from the cell lines GM4435 and GM0323 were comparable between six-cell aliquots and purified RNA (Collagen type I alpha-1 (COL1A1), P = 0.54; Fibroblast growth factor-5 (FGF5), P = 0.11; Laminin subunit beta-1 (LAMB1), P = 1.00 and Atlastin-1 (ATL1), P = 0.23). With respect to human blastocysts, 92% consistency was reported after comparing embryonic CCS results with previous diagnosis. A total of 30 genes from a human stem cell pluripotency panel were selected to evaluate gene expression in human embryos. Correlation coefficients of expression profiles from biopsies of the same embryo (r = 0.96 ± 0.03 (standard deviation), n = 45) were significantly higher than when biopsies from unrelated embryos were evaluated (r = 0.93 ± 0.03, n = 945) (P < 0.0001). Growth differentiation factor 3 (GDF3) was found to be significantly up-regulated in the inner cell mass (ICM), whereas Caudal type homebox protein-2 (CDX2), Laminin subunit alpha-1 (LAMA1) and DNA methyltransferase 3-beta (DNMT3B) showed down-regulation in ICM compared with TE. Trisomy 21 embryos showed significant up-regulation of markers of cell differentiation (Cadherin-5 (CDH5) and Laminin subunit gamma-1 (LAMC1)), whereas monosomy 21 blastocysts showed higher expression of genes reported to be expressed in undifferentiated cells (Gamma-Aminobutyric Acid Type-A Receptor Beta3 Subunit (GABRB3) and GDF3).

Large Scale Data: N/A.

Limitations, Reasons For Caution: Gene expression profiles of chromosomally normal embryos were not assessed due to restrictive access to euploid embryos for research. Nonetheless, the profile of blastocysts with single aneuploidies was characterized and compared. Only 30 target genes were analyzed for gene expression in this study. Increasing the number of target genes will provide a more comprehensive transcriptomic signature and reveal potential pathways paramount for embryonic competence and correct development.

Wider Implications Of The Findings: This is the first time that CCS and gene expression analysis have been performed on the same human preimplantation embryo biopsy. Further optimization of this protocol with other CCS platforms and inclusion of more target genes will provide innumerable research and clinical applications, such as discovery of biomarkers for embryonic reproductive potential and characterization of the transcriptomic signatures of embryos, potentially allowing for further embryo selection prior to embryo transfer and therefore improving outcomes.

Study Funding And Competing Interests: This study was funded by the Foundation for Embryonic Competence, Basking Ridge, NJ, USA. No conflicts of interests declared.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/molehr/gax014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420574PMC
May 2017

Identification and characterization of Aurora kinase B and C variants associated with maternal aneuploidy.

Mol Hum Reprod 2017 06;23(6):406-416

Department of Genetics, Rutgers, The State University of New Jersey, 145 Bevier Rd. Piscataway, NJ 08854, USA.

Study Question: Are single nucleotide variants (SNVs) in Aurora kinases B and C (AURKB, AURKC) associated with risk of aneuploid conception?

Summary Answer: Two SNVs were found in patients with extreme aneuploid concepti rates with respect to their age; one variant, AURKC p.I79V, is benign, while another, AURKB p.L39P, is a potential gain-of-function mutant with increased efficiency in promoting chromosome alignment.

What Is Known Already: Maternal age does not always predict aneuploidy risk, and rare gene variants can be drivers of disease. The AURKB and AURKC regulate chromosome segregation, and are associated with reproductive impairments in mouse and human.

Study Design, Size, Duration: An extreme phenotype sample selection scheme was performed for variant discovery. Ninety-six DNA samples were from young patients with higher than average embryonic aneuploidy rates and an additional 96 DNA samples were from older patients with lower than average aneuploidy rates.

Participants/materials, Setting, Methods: Using the192 DNA samples, the coding regions of AURKB and AURKC were sequenced using next generation sequencing. To assess biological significance, we expressed complementary RNA encoding the human variants in mouse oocytes. Assays such as determining subcellular localization and assessing catalytic activity were performed to determine alterations in protein function during meiosis.

Main Results And The Role Of Chance: Ten SNVs were identified using three independent variant-calling methods. Two of the SNVs (AURKB p.L39P and AURKC p.I79V) were non-synonymous and identified by at least two variant-identification methods. The variant encoding AURKC p.I79V, identified in a young woman with a higher than average rate of aneuploid embryos, showed wild-type localization pattern and catalytic activity. On the other hand, the variant encoding AURKB p.L39P, identified in an older woman with lower than average rates of aneuploid embryos, increased the protein's ability to regulate alignment of chromosomes at the metaphase plate. These experiments were repeated three independent times using 2-3 mice for each trial.

Large Scale Data: N/A.

Limitations, Reasons For Caution: Biological significance of the human variants was assessed in an in vitro mouse oocyte model where the variants are over-expressed. Therefore, the human protein may not function identically to the mouse homolog, or the same in mouse oocytes as in human oocytes. Furthermore, supraphysiological expression levels may not accurately reflect endogenous activity. Moreover, the evaluated variants were identified in one patient each, and no trial linking the SNV to pregnancy outcomes was conducted. Finally, the patient aneuploidy rates were established by performing comprehensive chromosome screening in blastocysts, and because of the link between female gamete aneuploidy giving rise to aneuploid embryos, we evaluate the role of the variants in Meiosis I. However, it is possible that the chromosome segregation mistake arose during Meiosis II or in mitosis in the preimplantation embryo. Their implications in human female meiosis and aneuploidy risk remain to be determined.

Wider Implications Of The Findings: The data provide evidence that gene variants exist in reproductively younger or advanced aged women that are predictive of the risk of producing aneuploid concepti in humans. Furthermore, a single amino acid in the N-terminus of AURKB is a gain-of-function mutant that could be protective of euploidy.

Study Funding/competing Interests: This work was supported by a Research Grant from the American Society of Reproductive Medicine and support from the Charles and Johanna Busch Memorial Fund at Rutgers, the State University of NJ to K.S. and the Foundation for Embryonic Competence, Inc to N.T. The authors declare no conflicts of interest.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/molehr/gax018DOI Listing
June 2017

Preimplantation embryonic mosaicism: origin, consequences and the reliability of comprehensive chromosome screening.

Curr Opin Obstet Gynecol 2017 Jun;29(3):168-174

aReproductive Medicine Associates of New Jersey, Basking Ridge, New Jersey bThomas Jefferson College of Biomedical Sciences, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.

Purpose Of Review: Embryonic mosaicism represents an ongoing challenge for contemporary comprehensive chromosome screening platforms due to the unknown reproductive potential of mosaic embryos and technical difficulties of its detection from a single embryo biopsy.

Recent Findings: Mosaicism in preimplantation embryos is a product of mitotic errors arising primarily from anaphase lag and chromosome nondisjunction. To date, there is high variability among estimations of prevalence of mosaicism in blastocysts, the most recent ranging from 3.3 to 83%. It has been reported that alleged mosaic embryos can develop into healthy babies, although the proper study evaluating this question remains to be completed. Technical artefacts from comprehensive chromosome screening platforms may also hinder correct classification of embryos as genuine mosaics.

Summary: Although complex, embryonic mosaicism is a phenomenon that deserves further investigation. Many embryos classified as mosaic may have actual reproductive potential. The predictive value of intermediate chromosome copy number assignments for the remaining embryo and for ongoing reproductive potential needs more careful consideration. In addition, recent advancements in extended embryo culture raise the possibility of investigating whether preferential segregation, selective advantage of normal cells or surveillance of abnormal chromosome numbers occur at postimplantation stages.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/GCO.0000000000000358DOI Listing
June 2017

Obtaining optic disc center and pixel region by automatic thresholding methods on morphologically processed fundus images.

Comput Methods Programs Biomed 2015 Feb 20;118(2):173-85. Epub 2014 Nov 20.

Department of Electronic, Computer Science and Automatic Engineering, "La Rábida" High Technical School of Engineering, University of Huelva, Spain. Electronic address:

Development of automatic retinal disease diagnosis systems based on retinal image computer analysis can provide remarkably quicker screening programs for early detection. Such systems are mainly focused on the detection of the earliest ophthalmic signs of illness and require previous identification of fundal landmark features such as optic disc (OD), fovea or blood vessels. A methodology for accurate center-position location and OD retinal region segmentation on digital fundus images is presented in this paper. The methodology performs a set of iterative opening-closing morphological operations on the original retinography intensity channel to produce a bright region-enhanced image. Taking blood vessel confluence at the OD into account, a 2-step automatic thresholding procedure is then applied to obtain a reduced region of interest, where the center and the OD pixel region are finally obtained by performing the circular Hough transform on a set of OD boundary candidates generated through the application of the Prewitt edge detector. The methodology was evaluated on 1200 and 1748 fundus images from the publicly available MESSIDOR and MESSIDOR-2 databases, acquired from diabetic patients and thus being clinical cases of interest within the framework of automated diagnosis of retinal diseases associated to diabetes mellitus. This methodology proved highly accurate in OD-center location: average Euclidean distance between the methodology-provided and actual OD-center position was 6.08, 9.22 and 9.72 pixels for retinas of 910, 1380 and 1455 pixels in size, respectively. On the other hand, OD segmentation evaluation was performed in terms of Jaccard and Dice coefficients, as well as the mean average distance between estimated and actual OD boundaries. Comparison with the results reported by other reviewed OD segmentation methodologies shows our proposal renders better overall performance. Its effectiveness and robustness make this proposed automated OD location and segmentation method a suitable tool to be integrated into a complete prescreening system for early diagnosis of retinal diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cmpb.2014.11.003DOI Listing
February 2015

Locating the fovea center position in digital fundus images using thresholding and feature extraction techniques.

Comput Med Imaging Graph 2013 Jul-Sep;37(5-6):386-93. Epub 2013 Jul 7.

Department of Mathematics, "La Rábida" High Technical School of Engineering, University of Huelva, Spain. Electronic address:

A new methodology for detecting the fovea center position in digital retinal images is presented in this paper. A pixel is firstly searched for within the foveal region according to its known anatomical position relative to the optic disc and vascular tree. Then, this pixel is used to extract a fovea-containing subimage on which thresholding and feature extraction techniques are applied so as to find fovea center. The methodology was evaluated on 1200 fundus images from the publicly available MESSIDOR database, 660 of which present signs of diabetic retinopathy. In 93.92% of these images, the distance between the methodology-provided and actual fovea center position remained below 1/4 of one standard optic disc radius (i.e., 17, 26, and 27 pixels for MESSIDOR retinas of 910, 1380 and 1455 pixels in size, respectively). These results outperform all the reviewed methodologies available in literature. Its effectiveness and robustness with different illness conditions makes this proposal suitable for retinal image computer analyses such as automated screening for early diabetic retinopathy detection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.compmedimag.2013.06.002DOI Listing
July 2014

A function for quality evaluation of retinal vessel segmentations.

IEEE Trans Med Imaging 2012 Feb 15;31(2):231-9. Epub 2011 Sep 15.

Department of Mathematics, La Rábida High Technical School of Engineering, University of Huelva, 21071 Palos de la Frontera, Spain.

Retinal blood vessel assessment plays an important role in the diagnosis of ophthalmic pathologies. The use of digital images for this purpose enables the application of a computerized approach and has fostered the development of multiple methods for automated vascular tree segmentation. Metrics based on contingency tables for binary classification have been widely used for evaluating the performance of these algorithms. Metrics from this family are based on the measurement of a success or failure rate in the detected pixels, obtained by means of pixel-to-pixel comparison between the automated segmentation and a manually-labeled reference image. Therefore, vessel pixels are not considered as a part of a vascular structure with specific features. This paper contributes a function for the evaluation of global quality in retinal vessel segmentations. This function is based on the characterization of vascular structures as connected segments with measurable area and length. Thus, its design is meant to be sensitive to anatomical vascularity features. Comparison of results between the proposed function and other general quality evaluation functions shows that this proposal renders a high matching degree with human quality perception. Therefore, it can be used to enhance quality evaluation in retinal vessel segmentations, supplementing the existing functions. On the other hand, from a general point of view, the applied concept of measuring descriptive properties may be used to design specialized functions aimed at segmentation quality evaluation in other complex structures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TMI.2011.2167982DOI Listing
February 2012

A new supervised method for blood vessel segmentation in retinal images by using gray-level and moment invariants-based features.

IEEE Trans Med Imaging 2011 Jan 9;30(1):146-58. Epub 2010 Aug 9.

Department of Electronic, Computer Science and Automatic Engineering, La Rábida Polytechnic School, University of Huelva, 21819 Palos de Frontera, Spain.

This paper presents a new supervised method for blood vessel detection in digital retinal images. This method uses a neural network (NN) scheme for pixel classification and computes a 7-D vector composed of gray-level and moment invariants-based features for pixel representation. The method was evaluated on the publicly available DRIVE and STARE databases, widely used for this purpose, since they contain retinal images where the vascular structure has been precisely marked by experts. Method performance on both sets of test images is better than other existing solutions in literature. The method proves especially accurate for vessel detection in STARE images. Its application to this database (even when the NN was trained on the DRIVE database) outperforms all analyzed segmentation approaches. Its effectiveness and robustness with different image conditions, together with its simplicity and fast implementation, make this blood vessel segmentation proposal suitable for retinal image computer analyses such as automated screening for early diabetic retinopathy detection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TMI.2010.2064333DOI Listing
January 2011

Detecting the optic disc boundary in digital fundus images using morphological, edge detection, and feature extraction techniques.

IEEE Trans Med Imaging 2010 Nov 17;29(11):1860-9. Epub 2010 Jun 17.

Department of Electronic, Computer Science and Automatic Engineering, ”La Rábida” Polytechnic School, University of Huelva, 21071 Huelva, Spain.

Optic disc (OD) detection is an important step in developing systems for automated diagnosis of various serious ophthalmic pathologies. This paper presents a new template-based methodology for segmenting the OD from digital retinal images. This methodology uses morphological and edge detection techniques followed by the Circular Hough Transform to obtain a circular OD boundary approximation. It requires a pixel located within the OD as initial information. For this purpose, a location methodology based on a voting-type algorithm is also proposed. The algorithms were evaluated on the 1200 images of the publicly available MESSIDOR database. The location procedure succeeded in 99% of cases, taking an average computational time of 1.67 s. with a standard deviation of 0.14 s. On the other hand, the segmentation algorithm rendered an average common area overlapping between automated segmentations and true OD regions of 86%. The average computational time was 5.69 s with a standard deviation of 0.54 s. Moreover, a discussion on advantages and disadvantages of the models more generally used for OD segmentation is also presented in this paper.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TMI.2010.2053042DOI Listing
November 2010

Nitric oxide synthase (NOS2/3) expression in head and neck squamous cell carcinomas in correlation with clinical patterns.

Onkologie 2009 Nov 16;32(11):655-60. Epub 2009 Oct 16.

Department of Otolaryngology, Head and Neck Surgery, University of Leipzig, Germany.

Background: Increased nitric oxide synthase (NOS) expression has been demonstrated in a number of carcinomas and is discussed to play a key role in tumor progression. The aim of this immunohistochemical study was to examine the protein expression rates of endothelial (e)NOS and inducible (i)NOS in head and neck squamous cell carcinomas (HNSCCs) and oral mucosa and to correlate the results with clinicopathologic factors (TN stage).

Patients And Methods: Protein expression patterns of NOS were studied immunohistochemically (score 0-7) in 58 patients with HNSCC and 7 mucosa samples, and the results were correlated with tumor stages.

Results: In oral mucosa, iNOS was only expressed in the basal epithelial layers and in macrophages, eNOS in endothelial cells and lymphocytes. In contrast, both NOS isoforms were expressed in HNSCC with preference at the tumor margins. 64% of tumor specimens demonstrated a positive eNOS immunoreactivity (score > or =3), 55% a positive iNOS immunoreactivity. NOS protein expression rates reached higher scores in tumors of patients with lymph node metastasis (N > 0; iNOS protein expression rate p < 0.05).

Conclusions: HNSCCs are able to express both NOS protein isoforms in relevant amounts, and we presume that synthesized NO is able to support angiogenetic patterns and facilitate tumor progression and lymphatic spread.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000242233DOI Listing
November 2009
-->