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1.
Reprod Biomed Online ; 36(6): 658-674, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29656830

RESUMEN

This proceedings report presents the outcomes from an international Expert Meeting to establish a consensus on the recommended technical and operational requirements for air quality within modern assisted reproduction technology (ART) laboratories. Topics considered included design and construction of the facility, as well as its heating, ventilation and air conditioning system; control of particulates, micro-organisms (bacteria, fungi and viruses) and volatile organic compounds (VOCs) within critical areas; safe cleaning practices; operational practices to optimize air quality while minimizing physicochemical risks to gametes and embryos (temperature control versus air flow); and appropriate infection-control practices that minimize exposure to VOC. More than 50 consensus points were established under the general headings of assessing site suitability, basic design criteria for new construction, and laboratory commissioning and ongoing VOC management. These consensus points should be considered as aspirational benchmarks for existing ART laboratories, and as guidelines for the construction of new ART laboratories.


Asunto(s)
Contaminación del Aire , Laboratorios/normas , Técnicas Reproductivas Asistidas/normas , Contaminación del Aire Interior , Consenso , Monitoreo del Ambiente , Humanos
2.
Hum Reprod ; 28(1): 10-21, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23054068

RESUMEN

STUDY QUESTION: Is there a need for a specific guide addressing studies of seminal quality? SUMMARY ANSWER: The proposed guidelines for the appraisal of SEMinal QUAlity studies (SEMQUA) reflect the need for improvement in methodology and research on semen quality. WHAT IS KNOWN ALREADY: From an examination of other instruments used to assess the quality of diagnostic studies, there was no guideline on studies of seminal quality. STUDY DESIGN, SIZE AND DURATION: Through systematic bibliographic search, potential items were identified and grouped into four blocks: participants, analytical methods, statistical methods and results. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Our findings were presented to a panel of experts who were asked to identify opportunities for improvement. Then, a checklist was designed containing the questions generated by the items that summarize the essential points that need to be considered for the successful outcome of a SEMQUA. MAIN RESULTS AND THE ROLE OF CHANCE: Eighteen items were identified, from which 19 questions, grouped into four blocks, were generated to constitute the final checklist. An explanation for the inclusion of each item was provided and some examples found in the bibliographic search were cited. LIMITATIONS AND REASONS FOR CAUTION: We consider that not all items are equally applicable to all study designs, and so the hypothetical results are not comparable. For that reason, a score would not be fair to critically appraise a study. This checklist is presented as an instrument for appraising SEMQUAs and therefore remains open to constructive criticism. It will be further developed in the future, in parallel with the continuing evolution of SEMQUAs. WIDER IMPLICATIONS OF THE FINDINGS: The final configuration of the SEMQUA is in the form of a checklist, and includes the items generally considered to be essential for the proper development of a SEMQUA. The final checklist produced has various areas of application; for example, it would be useful for designing and constructing a SEMQUA, for reviewing a paper on the question, for educational purposes or as an instrument for appraising the quality of research articles in this field. STUDY FUNDING/COMPETING INTEREST(S): None.


Asunto(s)
Guías de Práctica Clínica como Asunto , Análisis de Semen/normas , Investigación Biomédica/tendencias , Lista de Verificación , Europa (Continente) , Humanos , Infertilidad Masculina/diagnóstico , Masculino , Revisión de la Investigación por Pares/métodos , Sociedades Científicas , Agencias Voluntarias de Salud
3.
Zoology (Jena) ; 158: 126092, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37149944

RESUMEN

The Common Wasp, Vespula vulgaris (Hymenoptera: Vespidae), has an annual nest cycle with new colonies initiated by over-wintered queens. Survival of adult queen wasps through winter dormancy is enabled through the deposition of substantial quantities of triglycerides in fat bodies. Worker (and male) wasps lack these fat reserves. By comparing micro-CT scans of workers, pre-hibernation queens and post-hibernation queens, we demonstrate that it is possible to semi-quantitatively measure fat reserves using arbitrary X-ray attenuation ranges. Venom in the venom gland of the queen wasps, has a significantly lower X-ray attenuation value than the triglyceride-rich fat bodies. This may be due to its content of low molecular weight volatile pheromones in addition to its other known constituents. We also demonstrate the utility of micro-CT for visualising a range of physiological and anatomical features of insects. This non-destructive method for measuring fat reserves can be used on appropriately preserved or freshly collected insect specimens.


Asunto(s)
Avispas , Masculino , Animales , Avispas/fisiología , Rayos X , Feromonas , Estaciones del Año , Tomografía
4.
J Insect Physiol ; 149: 104547, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37451536

RESUMEN

X-ray micro-CT has been used to study the tracheal system of Pre and Post hibernation Queen wasps (Vespula vulgaris) and their workers. We have compared our findings in wasps with Snodgrass's description of the tracheal system of the honeybee as characterised by anatomical dissection. Our images, whilst broadly similar, identify the tracheal system as being considerably more complex than previously suggested. One of the 30 wasps imaged had a markedly different, previously undescribed tracheal system. Since completing this study, a large micro-CT study from the American Museum of Natural History (AMNH) has been published. This used different software (Slicer) and analysed 16bit digital data. We have compared our methods with that described in the AMNH publication, adopted their suggested nomenclature and have made recommendations for future studies.

5.
Hum Reprod ; 26(12): 3207-12, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21965314

RESUMEN

ESHRE has been running courses for basic semen analysis since 1994 and course material has been updated regularly in response to new findings and publications. Following publication of the 5th edition of the WHO laboratory manual, entitled WHO Laboratory Manual for the Examination and Processing of Human Semen (WHO5), the Subcommittee for training of the ESHRE Special Interest Group for Andrology evaluated potential amendments to its course. In respect of the updated ESHRE course, there are eight particular areas of discourse that are reviewed (i) maintaining the four-class differential motility count allowing distinction between rapid and slow progressive sperm for assisted reproduction technology. (ii) Maintaining the four-category assessment for sperm morphology with calculation of the teratozoospermic index. (iii) Continuing to advocate the use of three categories of results: 'normal', 'borderline' and 'abnormal' with respect to the clinical interpretation of the data. (iv) Presenting clear and unequivocal methods for performing assessments e.g. morphology. (v) Correcting the inconsistencies in WHO5, some of which are actually erroneous. (vi) Reducing the requirements for substantial extra work for what are unestablished improvements in accuracy and/or precision in the final results. (vii) Presentation of logical methods of sperm preparation. (viii) Discussion of the suddenly changed limits between fertile and subfertile men.


Asunto(s)
Andrología/educación , Educación Continua , Salud Reproductiva/educación , Análisis de Semen/métodos , Andrología/tendencias , Humanos , Masculino , Opinión Pública , Salud Reproductiva/tendencias , Semen/fisiología , Análisis de Semen/normas , Análisis de Semen/tendencias , Organización Mundial de la Salud
6.
Soc Sci Med ; 263: 113284, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32818851

RESUMEN

Compulsory co-payments limit access and may compromise quality in primary care. Patient Chosen Gap Payments (PCGPs) allow patients to specify a (voluntary) out-of-pocket contribution, creating an incentive for patient-centred care without the need for complex outcomes-based funding formulae. It is not yet known if widespread use of PCGP services is consistent with consumer preferences. We conducted a discrete choice experiment (DCE) in a sample of the adult Australian general population (n = 1457) during April 2019 to simulate patient choice between alternative primary care services and describe preferences for PCGP services. Participants also completed a supplementary valuation task in which participants reported their intended PCGP contribution for PCGP services. Finally, we conducted policy-simulations to predict market shares when PCGP clinics operate alongside the two existing models of primary care funding in Australia. Results suggest that patients prefer shorter wait time, longer consults, lower compulsory copayments, services with higher patient satisfaction ratings, choice of doctor and $0 suggested voluntary contribution for PCGP services. Policy-simulations suggest that high-quality PCGP services could obtain market share of up to 39% and voluntary contributions of up to $25.36 per service (95%CI: $10.24, $40.47), potentially adding $1.48 billion AUD in revenues and funding for primary care at no cost to government. Low-quality PCGP services are unlikely to capture significant market share and PCGP contributions were lowest for low-quality PCGP services ($12.12, 95%CI: $2.09, $26.34). Further field testing is recommended where (i) patients make consequential choices (e.g. real payments for simulated services), and (ii) dynamic effects on quality of care and utilisation can be observed; particularly in vulnerable populations. We conclude that PCGP services aligned with patient preferences could capture significant market share and substantially increase revenue to general practice.


Asunto(s)
Atención Dirigida al Paciente , Atención Primaria de Salud , Adulto , Australia , Humanos , Motivación , Prioridad del Paciente
7.
Sci Total Environ ; 678: 793-800, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31085495

RESUMEN

In recent years, the Stockholm Convention has listed an additional set of persistent organic pollutants (POPs) for elimination or restricted use/release. Data on the occurrence of these contaminants in food is scarce. Validated analytical methodology was developed to investigate the occurrence of hexachlorobutadiene (HCBD), pentachlorobenzene (PCBz), hexachlorobenzene (HCB) pentachlorophenol (PCP) and polychlorinated naphthalenes (PCNs) in 120 retail foods and 19 total diet study samples. The foods covered the range of commonly consumed dietary items including dairy products, eggs (hen and other species), poultry, meat, fish, vegetables, etc. HCBD showed a low frequency of detection, whereas PCBz, HCB and PCNs occurred in most samples (ranges: <0.01 to 0.19 µg/kg; <0.01 to 3.16 µg/kg and 0.1 to 166 ng ΣPCNs/kg respectively). PCP (<0.01 to 1.9 µg/kg) was detected more frequently in meat products, offal and eggs. Fish, shellfish, eggs from all species, animal fats, meat, offal and meat products showed higher contamination levels, which is normal when investigating lipophilic POPs. These levels of occurrence are similar to more recently reported literature levels but perhaps lower, relative to historic data. This is not unexpected, given the restrictions/limitations on these chemicals within the UK and Western Europe. The estimated human exposure to population groups through dietary intake is correspondingly low and based on current toxicological knowledge, the levels in the examined samples do not suggest a cause for health concern. The data also provide a current baseline for HCBD, PCBz and PCP, and update existing data for PCN and HCB occurrence in foods.


Asunto(s)
Exposición Dietética/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Contaminación de Alimentos/análisis , Animales , Reino Unido
8.
Environ Int ; 114: 219-230, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29522986

RESUMEN

The occurrence of a range of regulated and emerging organic environmental contaminants was investigated in 182 samples of edible marine fish sampled mainly from UK marine regions, but extending northerly to the coast of Norway and south to the Algarve. These species (sprats, mackerel, turbot, halibut, herring, grey mullet, sea bass, grey mullet, sardines, etc.) are among those considered to be at the highest risk of contamination with regulated contaminants such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins), and polychlorinated biphenyls (PCBs), but the occurrence of polybrominated diphenylethers (PBDEs) and polybrominated biphenyls (PBBs) was also investigated. Sub-sets of samples (50-75) were also analysed for emerging contaminants: polychlorinated naphthalenes (PCNs), polybrominated and mixed halogenated dibenzo-p-dioxins, dibenzofurans and biphenyls (PBDD/Fs, PXDD/Fs and PXBs) and perfluoroalkyl substances (PFAS). Contaminant occurrence varied with species and location, but all measured contaminants were detected, with sprats, sea bass, sardines, mackerel, and herring showing higher tissue concentrations. The concentrations of the different contaminants in the various samples were mapped utilising the GPS coordinate data of the capture locations to visualise spatial distribution levels. In terms of catch location, fish sampled from the coasts of southern Britain, north-western France and the Irish Sea appeared to contain proportionately higher levels of some contaminants - e.g. samples from the Irish Sea tended to show higher PCN concentrations, whereas higher levels of PCBs were observed in some fish sampled off the coasts of northern France. Similarly, samples of mullet from the southeast coast of UK showed much higher concentrations of BDE-99 than the other regions. In terms of occurrence trends, PCDD/F and PCB concentrations show a modest decline over the last decade but where limited background data is available for emerging contaminants, there is no evidence of downward trends.


Asunto(s)
Dioxinas y Compuestos Similares a la Dioxina/análisis , Peces/fisiología , Alimentos Marinos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Océanos y Mares , Reino Unido
9.
Best Pract Res Clin Obstet Gynaecol ; 21(4): 691-712, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17499552

RESUMEN

Patient safety incidents occur in approximately 10% of hospital admissions in the UK. Although robust data are not available, assisted conception is unlikely to be any less prone to adverse incidents; indeed there have been several high-profile cases which have drawn attention to this problem. Recently established national reporting systems for adverse events are collecting data which will inform trends in patient safety. Because of the nature of the work undertaken in assisted conception, there is the potential to affect not only future generations but also many patients simultaneously because of storage of biological material. It is therefore important to implement strategies to reduce the likelihood of patient safety incidents. Established methodologies exist for the reactive (root cause analysis) and the proactive assessment of risk (failure mode effects analysis). Furthermore, establishing the detail of a process and its context through process mapping is an important prerequisite for understanding its risk. The knowledge gained through these enquiries enables the implementation of an effective risk management programme which this chapter examines in detail.


Asunto(s)
Fertilización In Vitro/normas , Modelos Organizacionales , Administración de la Seguridad/métodos , Benchmarking , Femenino , Humanos , Masculino , Notificación Obligatoria , Errores Médicos , Medición de Riesgo/métodos
10.
Chemosphere ; 150: 472-478, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26733012

RESUMEN

Current occurrence data for polybrominated diphenyl ethers (PBDE) and hexa-bromocyclododecane (HBCD) measured in most commonly consumed foods (n = 156) and animal feeds (n = 51) sampled in the UK, demonstrates an ongoing ubiquity of these contaminants in human and animal diets. PBDE concentrations for the sum of 17 measured congeners ranged from 0.02 ng/g to 8.91 ng/g whole weight for food, and 0.11 ng/g to 9.63 ng/g whole weight for animal feeds. The highest concentration ranges, and mean values were detected in fish, processed foods and fish feeds. HBCD diastereomers (alpha-HBCD was the most commonly detected) generally occurred at lower concentrations (from <0.01 ng/g to 10.1 ng/g for food and <0.01 ng/g to 0.66 ng/g for animal feed) and less frequently than PBDEs, but tetrabromobisphenol A which was also measured, was rarely detected. The total bromine content of the samples was also determined in an attempt to use a mass balance approach to investigate some of these samples for the occurrence of novel and emerging BFRs. Although the approach was further refined by measuring organic bromine content, the concentrations of bromine were too high (in most cases by orders of magnitude) to allow use of the approach. A selected sub-set of samples was screened by GC-MS, for the presence of novel/emerging brominated flame retardants (PBT, TBX, PBEB, DBHCTD, HCTBPH and OBTMPI) but these were not detected at the higher limits of detection that result from full scan (GC-MS) screening. This data will contribute to the EU wide risk assessment on these contaminants.


Asunto(s)
Alimentación Animal/análisis , Bromo/análisis , Retardadores de Llama/análisis , Contaminación de Alimentos/análisis , Hidrocarburos Bromados/análisis , Animales , Monitoreo del Ambiente , Peces , Cromatografía de Gases y Espectrometría de Masas , Reino Unido
11.
Fertil Steril ; 48(3): 466-9, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3305089

RESUMEN

A single simple laboratory test for the detection of sperm surface antibodies is described. Spermatozoa from 300 men who were investigated for infertility were tested for sperm surface antibodies using the Immunobead test (IBT). IBTs for IgG, IgA, and IgM were performed on each sample as well as an IBT using an Immunobead with activity against both light and heavy immunoglobulin chains and therefore capable of detecting any of the three isotypes ("GAM-IBT"). An excellent correspondence was found between GAM-IBT-positive samples and those positive by one or more of the isotype-specific Immunobeads. In 29 of 32 positive tests, the GAM bead binding was within 5% of the most positive isotype-specific bead's binding. There were no false-positive or false-negative tests comparing the GAM-IBT with the isotype-specific IBTs.


Asunto(s)
Autoanticuerpos/análisis , Infertilidad Masculina/inmunología , Espermatozoides/inmunología , Antígenos de Superficie/inmunología , Humanos , Técnicas Inmunológicas , Masculino , Semen/análisis
12.
Fertil Steril ; 37(3): 410-5, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7060791

RESUMEN

In those patients whose infertility is unexplained after routine investigations, it is likely that there are defects of gamete transport, fertilization, or implantation. This paper describes the development of a test of sperm migration to the site of fertilization. A method of laparoscopic sperm recovery from the peritoneal cavity and fimbrial rinsings following insemination at midcycle is described. In all, 47 patients were studied, and spermatozoa were recovered in 55%. There was no difference in the success rate following artificial insemination or coital insemination. Successful sperm recovery could not be attributed to better semen quality or better timing of the procedure in the menstrual cycle. The spontaneous pregnancy rate in the positive sperm recovery group was significantly higher than in the negative group. A comparison was made between the results of the postcoital test and the results of laparoscopic sperm recovery. There was a poor correlation between the two tests. It is suggested that laparoscopic sperm recovery is useful in the investigation of and the further management of that group of patients whose infertility is unexplained.


Asunto(s)
Fertilización , Transporte Espermático , Moco del Cuello Uterino/análisis , Coito , Estradiol/sangre , Femenino , Humanos , Inseminación Artificial Homóloga , Masculino , Embarazo , Recuento de Espermatozoides , Motilidad Espermática
13.
Fertil Steril ; 50(6): 960-8, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3203762

RESUMEN

The sperm concentration and percentage motility values generated by version 3.2 of the CellSoft (Cryo Resources Ltd., New York, NY) automated semen analyzer on 200 ejaculates were compared with those obtained by standardized traditional methods. Overall, CellSoft gave mean concentrations that were 20.9 x 10(6)/ml lower (95% range of differences = -112.6 to +154.4 x 10(6)/ml). However, the difference between methods was not systematic. Below 50 x 10(6)/ml, CellSoft more often gave higher values, and above 100 x 10(6)/ml, it usually gave lower values. In the middle range, differences were randomly distributed. For motility, the CellSoft values were usually higher than those obtained by visual counting (mean difference = -17.5%, 95% range = -56.0% to +21.0%). Multiple regression analyses revealed a strong concentration dependency such that reliable values will probably be obtained only if all samples are diluted (with homologous seminal plasma) before CellSoft analysis. This upper concentration limit is of the order of 30 to 50 x 10(6)/ml. Without such dilution, this version of CellSoft will not provide sufficiently accurate values for basic semen characteristics and cannot be accepted as a routine diagnostic method.


Asunto(s)
Recuento de Espermatozoides , Motilidad Espermática , Humanos , Masculino , Métodos
14.
Fertil Steril ; 46(1): 97-103, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3087792

RESUMEN

An improved procedure for human sperm capacitation based upon calcium deprivation using a modified Tyrode's medium is described. Replacement of CaCl2 by SrCl2 significantly increased the penetration of zona-free hamster eggs after 20 hours of sperm preincubation, compared with parallel sperm aliquots incubated in normal medium. The effect of an extra 4 hours' sperm preincubation produced no significant shift in fertilizing ability. Addition of 0.1 mM ethyleneglycol-bis-(beta-amino-ethyl ether)-N,N,N',N'- tetraacetic acid (EGTA) to the strontium-substituted medium resulted in a further significant increase in the penetration rate as well as a significant increase in polyspermy. The average increase in the penetration capacity (penetration rate X polyspermy) of the strontium/EGTA-preincubated spermatozoa was approximately tenfold, with no significant shift as a result of an extra 4 hours' preincubation.


Asunto(s)
Capacitación Espermática/efectos de los fármacos , Interacciones Espermatozoide-Óvulo/efectos de los fármacos , Estroncio/farmacología , Animales , Calcio/fisiología , Cricetinae , Ácido Egtácico/farmacología , Femenino , Humanos , Técnicas In Vitro , Masculino , Motilidad Espermática/efectos de los fármacos , Zona Pelúcida/fisiología
15.
Fertil Steril ; 45(3): 357-65, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3949035

RESUMEN

Carefully timed and quantitated Kremer-type tests were performed for assessment of sperm-mucus interaction in 100 couples who underwent an infertility workup. A novel scoring system for these in vitro tests was elaborated and validated. The success of penetration of seminal spermatozoa into the mucus, and their migration within the mucus column, was related to both the sperm concentration and their motility, especially their progressivity. A calculated index of sperm motility quality gave a 70% accuracy rate in predicting the test result (normal versus abnormal), but this success rate was not significantly improved by incorporation of the sperm concentration into the index. No clear biologic relationship was found between this method for assessing Kremer-type tests (which correlated closely with accepted clinical reporting practices) and Katz's "percentage of successful collisions." This apparent discrepancy is considered to reflect basic differences in the approaches of the two scoring systems.


Asunto(s)
Moco del Cuello Uterino , Infertilidad/diagnóstico , Interacciones Espermatozoide-Óvulo , Femenino , Humanos , Masculino , Semen/análisis , Recuento de Espermatozoides , Motilidad Espermática , Transporte Espermático , Espermatozoides/fisiología
16.
Fertil Steril ; 59(1): 192-6, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8419207

RESUMEN

OBJECTIVE: To determine whether the mouse embryo culture system can be sensitized to provide improved differentiation of suboptimal culture media for in vitro fertilization. DESIGN: Mouse embryo development in media prepared from one of three water sources were compared using embryos from two mouse strains, culturing embryos from either zygote or two-cell stage, and pretreating with either zona removal and/or cryopreservation. SETTING: Academic research department, tertiary care referral center. RESULTS: Embryos from CD1 mice were able to develop in suboptimal culture conditions, even when pretreated with zona removal or cryopreservation. Embryos from B6CBA/F1J mice were more sensitive to suboptimal culture conditions when harvested at the zygote stage than at the two-cell stage, and this sensitivity was improved after zona removal before culture. CONCLUSIONS: The mouse embryo culture system has deficiencies as an assay of culture medium quality, but the sensitivity of the assay can be optimized by harvesting at the zygote stage from an appropriate strain and by zona pellucida removal before culture.


Asunto(s)
Fertilización In Vitro , Ratones/embriología , Control de Calidad , Animales , Medios de Cultivo , Técnicas de Cultivo , Desarrollo Embrionario y Fetal , Humanos , Sensibilidad y Especificidad
17.
Fertil Steril ; 38(2): 212-21, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7106315

RESUMEN

A detailed analysis of semen quality was carried out in 85 couples with unexplained infertility by the use of conventional criteria of semen analysis, time-exposure photomicrography, and the zona-free hamster egg penetration test. According to the latter, 34.1% of the male partners exhibited evidence of defective sperm function, although only 4% of these patients were devoid of any demonstrable fertilizing capacity. Of the conventional parameters of semen analysis examined, the most revealing was the morphologic character of the sperm, which was significantly poorer (P less than 0.001) in the group with unexplained infertility than in the normal fertile control group and also showed a significant relationship (P less than 0.001) with the presence of subnormal fertilizing capacity in the hamster egg assay. A majority of movement characteristics measured by time-exposure photomicrography were significantly depressed in the group with unexplained infertility, compared with the normal fertile control group. In addition, certain of the movement characteristics investigated were significantly related to the fertilizing capacity of the spermatozoa; and, in this respect, a progressive swimming speed (greater than 25 micrometers/sec), a straight swimming mode of progression, and a small amplitude of lateral head displacement (Ah) all appeared to be important qualities.


Asunto(s)
Infertilidad Masculina/etiología , Espermatozoides/fisiología , Animales , Cricetinae , Femenino , Humanos , Masculino , Semen/análisis , Recuento de Espermatozoides , Motilidad Espermática , Interacciones Espermatozoide-Óvulo
18.
J Androl ; 11(3): 195-203, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2384341

RESUMEN

Suspensions of seminal plasma-free human spermatozoa were prepared by swim-up from semen and studied using high magnification videomicrography after incubation under capacitating conditions for 1.5-2 h. Three subpopulations of capacitating spermatozoa showing different patterns of motility could be distinguished visually: forward progressive, transition phase, and hyperactivated motility. The purpose of this study was not to determine the relative proportions of spermatozoa in these three categories but to describe their movement characteristics. Manual track plotting and analysis allowed value derivation for the curvilinear, average path and straight-line velocities (VCL, VAP, and VSL respectively); for the three progression ratios of linearity (LIN = VSL divided by VCL X 100), straightness (STR = VSL divided by VAP X 100), and wobble (WOB = VAP divided by VCL X 100); and also for the amplitude of lateral head displacement (ALH) and the beat/cross frequency (BCF). Algorithms produced from these motion characteristics allowed distinctions to be made between cell motility patterns. Spermatozoa with straight-line velocity (VSL) greater than or equal to 40 microns/s, linearity (LIN) greater than or equal to 60% and amplitude of lateral head displacement (ALH) less than 5 microns were FP or non-hyperactivated. Tracks with curvilinear velocity (VCL) greater than or equal to 100 microns/s, linearity (LIN) less than 60% and amplitude of lateral head displacement (ALH) greater than or equal to 5 microns showed concomitants of hyperactivation. Classical hyperactivated tracks also showed straightness (STR) less than 60% and straight-line velocity (VSL) less than 30 microns/s.


Asunto(s)
Capacitación Espermática/fisiología , Motilidad Espermática/fisiología , Espermatozoides/fisiología , Humanos , Técnicas In Vitro , Masculino , Fotomicrografía , Grabación de Cinta de Video
19.
Clin Chim Acta ; 271(2): S5-26, 1998 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-9565337

RESUMEN

This document is the first recommendation on the presentation of properties in reproduction and fertility and their values in clinical laboratory sciences from The International Society of Andrology, IFCC and IUPAC. It forms part of the ongoing effort to standardise requests and reporting of laboratory data for transmission across cultural and linguistic domains, without attempting to standardise the language used by clinicians and laboratory practitioners. The document is accessible on Internet from C-NPU home page address: http://inet.uni-c.dk/ home/ifcc_iupac_cnpu.


Asunto(s)
Química Clínica/normas , Fertilidad , Reproducción , Química Clínica/métodos , Femenino , Humanos , Masculino , Estándares de Referencia , Terminología como Asunto
20.
Toxicol Lett ; 14(1-2): 15-20, 1982 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7157413

RESUMEN

Rats were dosed once per os with either plant-incorporated or solution-radioactive methylmercury (MeHg). While whole-body retention did not change, the incorporation into some organs was approx. 2.5 X higher when administered Hg was in the plant-incorporated rather than in solution form. The only noticeable change in demethylation occurred in the cerebrum where MeHg:Hg ratios were 79:10 (plant-incorporated MeHg) and 65:24 (solution-MeHg). Between 5 to 7% of the total mercury was excreted in faeces and urine either in the inorganic (faeces) or organic (urine) forms. Mercury levels in mitochondrial and soluble fractions of cerebrum were noticeably lower with plant-MeHg than with solution-MeHg.


Asunto(s)
Compuestos de Metilmercurio/farmacología , Plantas/metabolismo , Animales , Remoción de Radical Alquila , Heces/análisis , Femenino , Mercurio/metabolismo , Unión Proteica , Ratas , Ratas Endogámicas , Distribución Tisular
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