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Cissen M, Meijerink AM, D'Hauwers KW, Meissner A, van der Weide N, Mochtar MH, de Melker AA, Ramos L, Repping S, Braat DDM, Fleischer K, van Wely M. Prediction model for obtaining spermatozoa with testicular sperm extraction in men with non-obstructive azoospermia. Hum Reprod 2016; 31:1934-41. [PMID: 27406950 DOI: 10.1093/humrep/dew147] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 05/02/2016] [Indexed: 11/15/2022] Open
Abstract
STUDY QUESTION Can an externally validated model, based on biological variables, be developed to predict successful sperm retrieval with testicular sperm extraction (TESE) in men with non-obstructive azoospermia (NOA) using a large nationwide cohort? SUMMARY ANSWER Our prediction model including six variables was able to make a good distinction between men with a good chance and men with a poor chance of obtaining spermatozoa with TESE. WHAT IS KNOWN ALREADY Using ICSI in combination with TESE even men suffering from NOA are able to father their own biological child. Only in approximately half of the patients with NOA can testicular sperm be retrieved successfully. The few models that have been developed to predict the chance of obtaining spermatozoa with TESE were based on small datasets and none of them have been validated externally. STUDY DESIGN, SIZE, DURATION We performed a retrospective nationwide cohort study. Data from 1371 TESE procedures were collected between June 2007 and June 2015 in the two fertility centres. PARTICIPANTS/MATERIALS, SETTING, METHODS All men with NOA undergoing their first TESE procedure as part of a fertility treatment were included. The primary end-point was the presence of one or more spermatozoa (regardless of their motility) in the testicular biopsies.We constructed a model for the prediction of successful sperm retrieval, using univariable and multivariable binary logistic regression analysis and the dataset from one centre. This model was then validated using the dataset from the other centre. The area under the receiver-operating characteristic curve (AUC) was calculated and model calibration was assessed. MAIN RESULTS AND THE ROLE OF CHANCE There were 599 (43.7%) successful sperm retrievals after a first TESE procedure. The prediction model, built after multivariable logistic regression analysis, demonstrated that higher male age, higher levels of serum testosterone and lower levels of FSH and LH were predictive for successful sperm retrieval. Diagnosis of idiopathic NOA and the presence of an azoospermia factor c gene deletion were predictive for unsuccessful sperm retrieval. The AUC was 0.69 (95% confidence interval (CI): 0.66-0.72). The difference between the mean observed chance and the mean predicted chance was <2.0% in all groups, indicating good calibration. In validation, the model had moderate discriminative capacity (AUC 0.65, 95% CI: 0.62-0.72) and moderate calibration: the predicted probability never differed by more than 9.2% of the mean observed probability. LIMITATIONS, REASONS FOR CAUTION The percentage of men with Klinefelter syndrome among men diagnosed with NOA is expected to be higher than in our study population, which is a potential selection bias. The ability of the sperm retrieved to fertilize an oocyte and produce a live birth was not tested. WIDER IMPLICATIONS OF THE FINDINGS This model can help in clinical decision-making in men with NOA by reliably predicting the chance of obtaining spermatozoa with TESE. STUDY FUNDING/COMPETING INTEREST This study was partly supported by an unconditional grant from Merck Serono (to D.D.M.B. and K.F.) and by the Department of Obstetrics and Gynaecology of Radboud University Medical Center, Nijmegen, The Netherlands, the Department of Obstetrics and Gynaecology, Jeroen Bosch Hospital, Den Bosch, The Netherlands, and the Department of Obstetrics and Gynaecology, Academic Medical Center, Amsterdam, The Netherlands. Merck Serono had no influence in concept, design nor elaboration of this study. TRIAL REGISTRATION NUMBER Not applicable.
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Meijerink AM, Cissen M, Mochtar MH, Fleischer K, Thoonen I, de Melker AA, Meissner A, Repping S, Braat DDM, van Wely M, Ramos L. Prediction model for live birth in ICSI using testicular extracted sperm. Hum Reprod 2016; 31:1942-51. [PMID: 27406949 DOI: 10.1093/humrep/dew146] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 05/26/2016] [Indexed: 01/09/2023] Open
Abstract
STUDY QUESTION Which parameters have a predictive value for live birth in couples undergoing ICSI after successful testicular sperm extraction (TESE-ICSI)? SUMMARY ANSWER Female age, a first or subsequent started TESE-ICSI cycle, male LH, male testosterone, motility of the spermatozoa during the ICSI procedure and the initial male diagnosis before performing TESE were identified as relevant and independent parameters for live birth after TESE-ICSI. WHAT IS KNOWN ALREADY In reproductive medicine prediction models are used frequently to predict treatment success, but no prediction model currently exists for live birth after TESE-ICSI. STUDY DESIGN, SIZE, DURATION A retrospective cohort study between 2007 and 2015 in two academic hospitals including 1559 TESE-ICSI cycles. The prediction model was developed using data from one centre and validation was performed with data from the second centre. PARTICIPANTS/MATERIALS, SETTING, METHODS We included couples undergoing ICSI treatment with surgically retrieved sperm from the testis for the first time. In the development set we included 526 couples undergoing 1006 TESE-ICSI cycles. In the validation set we included 289 couples undergoing 553 TESE-ICSI cycles. Multivariable logistic regression models were constructed in a stepwise fashion (P < 0.2 for entry). The external validation was based on discrimination and calibration. MAIN RESULTS AND THE ROLE OF CHANCE We included 224 couples (22.3%) with a live birth in the development set. The occurrence of a live birth was associated with lower female age, first TESE-ICSI cycle, lower male LH, higher male testosterone, the use of motile spermatozoa for ICSI and having obstructive azoospermia as an initial suspected diagnosis. The area under the receiver operating characteristic (ROC) curve was 0.62. From validation data, the model had moderate discriminative capacity (c-statistic 0.67, 95% confidence interval: 0.62-0.72) but calibrated well, with a range from 0.06 to 0.56 in calculated probabilities. LIMITATIONS, REASONS FOR CAUTION We had a lack of data about the motility of spermatozoa during TESE, therefore, we used motility of the spermatozoa used for ICSI after freeze-thawing, information which is only available during treatment. We had to exclude data on paternal BMI in the model because too many missing values in the validation data hindered testing. We did not include a histologic diagnosis, which would have made our data set less heterogeneous and, finally, our model may not be applicable in centres which have a different policy for the indication for performing sperm extraction. The prognostic value of the model is limited because of a low 'area under the curve'. WIDER IMPLICATIONS OF THE FINDINGS This model enables the differentiation between couples with a low or high chance to reach a live birth using TESE-ICSI. As such it can aid in the counselling of patients and in clinical decision-making. STUDY FUNDING/COMPETING INTERESTS This study was partly supported by an unconditional grant from Merck Serono (to D.D.M.B. and K.F.) and by the Department of Obstetrics and Gynaecology of Radboud University Medical Center, Nijmegen, The Netherlands, the Department of Obstetrics and Gynaecology, Jeroen Bosch Hospital, Den Bosch, The Netherlands, and the Department of Obstetrics and Gynaecology, Academic Medical Center, Amsterdam, The Netherlands. Merck Serono had no influence in concept, design, nor elaboration of this study. TRIAL REGISTRATION NUMBER Not applicable.
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Banc A, Charbonneau C, Dahesh M, Appavou MS, Fu Z, Morel MH, Ramos L. Small angle neutron scattering contrast variation reveals heterogeneities of interactions in protein gels. SOFT MATTER 2016; 12:5340-5352. [PMID: 27198847 DOI: 10.1039/c6sm00710d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We propose a quantitative approach to probe the spatial heterogeneities of interactions in macromolecular gels, based on a combination of small angle X-ray (SAXS) and neutrons (SANS) scattering. We investigate the structure of model gluten protein gels and show that the gels display radically different SAXS and SANS profiles when the solvent is (at least partially) deuterated. The detailed analysis of the SANS signal as a function of the solvent deuteration demonstrates heterogeneities of sample deuteration at different length scales. The progressive exchange between the protons (H) of the proteins and the deuteriums (D) of the solvent is inhomogeneous and 60 nm large zones that are enriched in H are evidenced. In addition, at low protein concentration, in the sol state, solvent deuteration induces a liquid/liquid phase separation. Complementary biochemical and structure analyses show that the denser protein phase is more protonated and specifically enriched in glutenin, the polymeric fraction of gluten proteins. These findings suggest that the presence of H-rich zones in gluten gels would arise from the preferential interaction of glutenin polymers through a tight network of non-exchangeable intermolecular hydrogen bonds.
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Ramos K, Gómez-Gómez M, Cámara C, Ramos L. Silver speciation and characterization of nanoparticles released from plastic food containers by single particle ICPMS. Talanta 2016; 151:83-90. [DOI: 10.1016/j.talanta.2015.12.071] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 12/21/2015] [Accepted: 12/26/2015] [Indexed: 01/03/2023]
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Ramos L, Perez Azorin JF. Comment on "A protocol for EBT3 radiochromic film dosimetry using reflection dosimetry using scanning" [Med. Phys. 41(12), 122101 (6pp.) (2014)]. Med Phys 2015; 42:2096-7. [PMID: 25832100 DOI: 10.1118/1.4914853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Duran J, Cusicanqui M, Laforcada C, Fortun F, Cruz D, Ramos L, Muñoz D, Torrez J, condori J, Copa H. Prevalence of cognitive impairment in older adults in rural areas of La Paz, measured with four neurocognitive test. J Neurol Sci 2015. [DOI: 10.1016/j.jns.2015.08.400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Meira T, Ramos L, Santos C, Fonseca J. MON-PP186: Feeding Tube Transparietal Thickness Could be a Nutritional Status Indicator? Clin Nutr 2015. [DOI: 10.1016/s0261-5614(15)30618-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wang E, Ozimek J, Greene N, Ramos L, Vyas N, Kilpatrick S, Pisarska M. Impact of ART on severe maternal morbidity. Fertil Steril 2015. [DOI: 10.1016/j.fertnstert.2015.07.672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Escobar-Arnanz J, Ramos L. The latest trends in the miniaturized treatment of solid samples. Trends Analyt Chem 2015. [DOI: 10.1016/j.trac.2015.02.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Quirce R, Martínez-Rodríguez I, Banzo I, de Arcocha-Torres M, Jiménez-Bonilla J, Martínez-Amador N, Ibáñez-Bravo S, Ramos L, Amado J, Carril J. 18F-sodium fluoride PET/CT for the in vivo visualization of Mönckeberg's sclerosis in a diabetic patient. Rev Esp Med Nucl Imagen Mol 2015. [DOI: 10.1016/j.remnie.2015.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Joaquim J, Matos C, Pires T, Fonseca F, Tavares O, Ramos L, Rocha M. Assessment of Adverse Reactions due to an Iodine-based Contrast Agent. Clin Ther 2015. [DOI: 10.1016/j.clinthera.2015.05.298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hessel M, de Vries M, D'Hauwers KWM, Fleischer K, Hulsbergen-van de Kaa CA, Braat DDM, Ramos L. Cytological evaluation of spermatogenesis: a novel and simple diagnostic method to assess spermatogenesis in non-obstructive azoospermia using testicular sperm extraction specimens. Andrology 2015; 3:481-90. [DOI: 10.1111/andr.12023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 12/15/2014] [Accepted: 02/04/2015] [Indexed: 11/29/2022]
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Sanz-Landaluze J, Pena-Abaurrea M, Muñoz-Olivas R, Cámara C, Ramos L. Zebrafish (Danio rerio) eleutheroembryo-based procedure for assessing bioaccumulation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:1860-9. [PMID: 25590991 DOI: 10.1021/es504685c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This paper reports on the development and preliminary evaluation of a new bioaccumulation test based on the use of zebrafish (Danio renio) eleutheroembryos (72 h after hatching, corresponding to 144 h post fertilization, hpf) as an alternative to adult fish-based procedures for regulatory purposes regarding REACH application. The proposed test accomplished the OECD 305 guideline and consists of a 48 h uptake period followed by a 24 h depuration step. Bioaccumulation experiments were performed for a selected of hyper hydrophobic chemicals (log Kow> 7.6), that is, PCB 136 and PBDE 154 at two concentration levels corresponding roughly to 1% and 0.1% the chemicaĺs LC50(nominal concentrations of 4.0 and 12.0 μg/L for PCB 136, and 1.0 and 5.0 μg/L PBDE 154, respectively). Toxicokinetic models were used to calculate the bioconcentration factors (BCFs) based on of the chemical concentrations found in the contaminated eleutheroembryos and their surrounding media. The experimentally determined accumulation profiles show bioaccumulation by zebrafish eleutheroembryos of both chemicals, and that the process is more complex than simple water-lipid partition. Calculated log BCFs using a first-order accumulation model(3.97 and 3.73 for PCB 136, and 3.95 and 4.29 for PBDE 154) were in the range of those previously reported in the literature. The suitability of this new nonprotected life stage bioaccumulation protocol for BCF estimation was evaluated by application to widely divergent micropollutants with different accumulation mechanisms. The results were compared with those in the MITE-NITE database for adult rice fish (Oryzias latipes).
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Chávez B, Ramos L, García-Becerra R, Vilchis F. Hamster SRD5A3 lacks steroid 5α-reductase activity in vitro. Steroids 2015; 94:41-50. [PMID: 25498908 DOI: 10.1016/j.steroids.2014.11.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 08/28/2014] [Accepted: 11/28/2014] [Indexed: 11/28/2022]
Abstract
According to current knowledge, two steroid 5α-reductases, designated type 1 (SRD5A1) and type 2 (SRD5A2), are present in all species examined to date. These isozymes play a central role in steroid hormone physiology by catalyzing the reduction of 3-keto-4-ene-steroids into more active 5α-reduced derivatives, including the conversion of testosterone (T) to dihydrotestosterone (DHT). A third 5α-reductase (SRD5A3, -type 3), which is overexpressed in hormone-refractory prostate cancer cells, has been identified; however, its enzymatic characteristics are practically unknown. Here, we isolated a cDNA encoding hamster Srd5a3 (hSrd5a3) and performed functional metabolic assays to investigate its biochemical properties. The cloned cDNA encodes a 330 amino acid protein that is 87% identical to the homologous protein in mice and 78% to that in humans. However, hSrd5a3 exhibits low sequence homology with its counterparts hSrd5a1 (19%) and hSrd5a2 (17%). A fusion protein consisting of hSrd5a3 and green fluorescent protein provided evidence for cytoplasmic localization in transfected mammalian cells. Real-time PCR analysis revealed that, Srd5a3 mRNA was present in nearly all hamster tissues, with high expression in the cerebellum, Harderian gland and testis. Functional assays expressing hSrd5a3 cDNA in HEK-293 cells revealed that this isozyme is unable to reduce T into DHT. Further expression assays confirmed that similar to testosterone, progesterone, androstenedione and corticosterone are not reduced by hSrd5a3 or human SRD5A3. Together, these results indicate that hSrd5a3 lacks the catalytic activity to transform 3-keto-4-ene-compounds; therefore 5α-reductase type 3 may not be involved in 5α-reduction of steroids.
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Artiaga G, Ramos K, Ramos L, Cámara C, Gómez-Gómez M. Migration and characterisation of nanosilver from food containers by AF4-ICP-MS. Food Chem 2015; 166:76-85. [DOI: 10.1016/j.foodchem.2014.05.139] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 05/20/2014] [Accepted: 05/26/2014] [Indexed: 11/25/2022]
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Hicks C, Ramos L, Reekie T, Misagh GH, Narlawar R, Kassiou M, McGregor IS. Body temperature and cardiac changes induced by peripherally administered oxytocin, vasopressin and the non-peptide oxytocin receptor agonist WAY 267,464: a biotelemetry study in rats. Br J Pharmacol 2014; 171:2868-87. [PMID: 24641248 DOI: 10.1111/bph.12613] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 01/14/2014] [Accepted: 01/26/2014] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE There is current interest in oxytocin (OT) as a possible therapeutic in psychiatric disorders. However, the usefulness of OT may be constrained by peripheral autonomic effects, which may involve an action at both OT and vasopressin V1A receptors. Here, we characterized the cardiovascular and thermoregulatory effects of OT, vasopressin (AVP) and the non-peptide OT receptor agonist WAY 267,464 in rats, and assessed the relative involvement of the OT and V1A receptors in these effects. EXPERIMENTAL APPROACH Biotelemetry in freely moving male Wistar rats was used to examine body temperature and heart rate after OT (0.01 - 1 mg kg(-1); i.p.), AVP (0.001 - 0.1 mg kg(-1); i.p.) or WAY 267,464 (10 and 100 mg kg(-1); i.p.). The actions of the OT receptor antagonist Compound 25 (C25, 5 and 10 mg kg(-1)) and V1A receptor antagonist SR49059 (1 and 10 mg kg(-1)) were studied, as well as possible V1A receptor antagonist effects of WAY 267,464. KEY RESULTS OT and AVP dose-dependently reduced body temperature and heart rate. WAY 267,464 had similar, but more modest, effects. SR49059, but not C25, prevented the hypothermia and bradycardia induced by OT and AVP. WAY 267,464 (100 mg·kg(-1)) prevented the effects of OT, and to some extent AVP. CONCLUSIONS AND IMPLICATIONS Peripherally administered OT and AVP have profound cardiovascular and thermoregulatory effects that appear to principally involve the V1A receptor rather than the OT receptor. Additionally, WAY 267,464 is not a simple OT receptor agonist, as it has functionally relevant V1A antagonist actions.
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de Boer P, de Vries M, Ramos L. A mutation study of sperm head shape and motility in the mouse: lessons for the clinic. Andrology 2014; 3:174-202. [PMID: 25511638 DOI: 10.1111/andr.300] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 09/19/2014] [Accepted: 09/24/2014] [Indexed: 12/11/2022]
Abstract
Mouse mutants that show effects on sperm head shape, the sperm tail (flagellum), and motility were analysed in a systematic way. This was achieved by grouping mutations in the following classes: manchette, acrosome, Sertoli cell contact, chromatin remodelling, and mutations involved in complex regulations such as protein (de)phosphorylation and RNA stability, and flagellum/motility mutations. For all mutant phenotypes, flagellum function (motility) was affected. Head shape, including the nucleus, was also affected in spermatozoa of most mouse models, though with considerable variation. For the mutants that were categorized in the flagellum/motility group, generally normal head shapes were found, even when the flagellum did not develop or only poorly so. Most mutants are sterile, an occasional one semi-sterile. For completeness, the influence of the sex chromosomes on sperm phenotype is included. Functionally, the genes involved can be categorized as regulators of spermiogenesis. When extrapolating these data to human sperm samples, in vivo selection for motility would be the tool for weeding out the products of suboptimal spermiogenesis and epididymal sperm maturation. The striking dependency of motility on proper sperm head development is not easy to understand, but likely is of evolutionary benefit. Also, sperm competition after mating can never act against the long-term multi-generation interest of genetic integrity. Hence, it is plausible to suggest that short-term haplophase fitness i.e., motility, is developmentally integrated with proper nucleus maturation, including genetic integrity to protect multi-generation fitness. We hypothesize that, when the prime defect is in flagellum formation, apparently a feedback loop was not necessary as head morphogenesis in these mutants is mostly normal. Extrapolating to human-assisted reproductive techniques practice, this analysis would supply the arguments for the development of tools to select for motility as a continuous (non-discrete) parameter.
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Coutinho I, Moreira S, Ramos L, Robalo Cordeiro M, Cardoso J, Gonçalo M, Tellechea O. Plaque-like papular xanthoma: a new variant of non-Langerhans cell disease. J Eur Acad Dermatol Venereol 2014; 30:332-3. [DOI: 10.1111/jdv.12725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Ramos L, Tellechea O, Moreno A, Martins L, Neves N, Januário G, Rodrigues C. Childhood bullous pemphigoid: report of 2 cases. J Eur Acad Dermatol Venereol 2014; 30:330-2. [PMID: 25186446 DOI: 10.1111/jdv.12724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Alarcón P, Díaz C, Tagle T, Ramos L, Quintana M. Metáforas para profesor y estudiante de pedagogía, en un grupo de estudiantes de pedagogía chilenos / Metaphors on teachers and student-teachers from the perspective of a group of chilean teacher candidates. ACTUALIDADES INVESTIGATIVAS EN EDUCACIÓN 2014. [DOI: 10.15517/aie.v14i2.14829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Ramos L, Barreira N, Mosquera A, Penedo MG, Yebra-Pimentel E, García-Resúa C. Analysis of parameters for the automatic computation of the tear film break-up time test based on CCLRU standards. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2014; 113:715-724. [PMID: 24438992 DOI: 10.1016/j.cmpb.2013.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/08/2013] [Accepted: 12/09/2013] [Indexed: 06/03/2023]
Abstract
Dry eye syndrome is affecting a remarkable percentage of population. The prevalence is 10-15% of normal population, and 18-30% of contact lenses users. The break-up time (BUT) is a clinical test used for the diagnosis of this disease. In this work, we perform an analysis of parameters for a global and a local automatic computation of the BUT measure, based on criteria of specificity and sensitivity. We have tested our methodology on a dataset composed of 18 videos annotated by 4 different experts. The local analysis preserves the results of the global approach providing useful additional information about the break-up tear zone.
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Ramos L, Barreira N, Pena-Verdeal H, Giráldez MJ. Automatic assessment of tear film break-up dynamics. Stud Health Technol Inform 2014; 207:173-182. [PMID: 25488223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Dry eye syndrome is a common disorder of the tear film which affects a remarkable percentage of the population. The Break-Up Time (BUT) is a clinical test used for the diagnosis of this disease, which computes the time the first tear film break-up appears. This work describes a fully automatic methodology to compute the BUT measurement and evaluate the break-up dynamics until the final blink. This analysis provides useful additional information for the assessment of tear film stability.
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Cruz Ortega R, Anaya AL, Ramos L. Effects of allelopathic compounds of corn pollen on respiration and cell division of watermelon. J Chem Ecol 2013; 14:71-86. [PMID: 24276995 DOI: 10.1007/bf01022532] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/1986] [Accepted: 01/07/1987] [Indexed: 11/26/2022]
Abstract
The effects of the allelopathic compounds of an "'ethanolic extract" of corn pollen on growth, respiration, and cellular division of watermelon (Citrullus lanatus, var. peacock improved) were studied. Bioassays with the ethanolic extract showed an inhibition of radicle and hypocotyl growth. The effects on respiration were observed in isolated watermelon hypocotyl mitochondria. The ethanolic extract acts as an inhibitor of the electron pathway, decreasing oxygen consumption in state 3, with malate and succinate substrates. The specific inhibition site probably is located before the cytochromec. Ascorbate-TMPD as substrate reversed the inhibitory effect of the ethanolic extract. An evaluation of the mitotic index was made in slide preparations of previously treated meristematic cells. A decrease in mitotic activity of more than 50% was found, as well as irregular and pycnotic nuclei. The data obtained from this study reflect an important mechanism of action of the allelopathic compounds of corn pollen.
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Pena-Abaurrea M, García de la Torre V, Ramos L. Ultrasound-assisted extraction followed by disposable pipette purification for the determination of polychlorinated biphenyls in small-size biological tissue samples. J Chromatogr A 2013; 1317:223-9. [DOI: 10.1016/j.chroma.2013.07.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 11/16/2022]
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