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1.
Nat Commun ; 15(1): 5029, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866733

RESUMEN

Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black-hole and neutron-star magnetospheres, where accretion-powered jets and pulsar winds are expected to be enriched with electron-positron pairs. Their role in the dynamics of such environments is in many cases believed to be fundamental, but their behavior differs significantly from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies, which are rather limited. We present the first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN's Super Proton Synchrotron (SPS) accelerator. Monte Carlo simulations agree well with the experimental data and show that the characteristic scales necessary for collective plasma behavior, such as the Debye length and the collisionless skin depth, are exceeded by the measured size of the produced pair beams. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations.

2.
Phys Rev Lett ; 130(19): 195101, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37243644

RESUMEN

We present results from pulsed-power driven differentially rotating plasma experiments designed to simulate physics relevant to astrophysical disks and jets. In these experiments, angular momentum is injected by the ram pressure of the ablation flows from a wire array Z pinch. In contrast to previous liquid metal and plasma experiments, rotation is not driven by boundary forces. Axial pressure gradients launch a rotating plasma jet upward, which is confined by a combination of ram, thermal, and magnetic pressure of a surrounding plasma halo. The jet has subsonic rotation, with a maximum rotation velocity 23±3 km/s. The rotational velocity profile is quasi-Keplerian with a positive Rayleigh discriminant κ^{2}∝r^{-2.8±0.8} rad^{2}/s^{2}. The plasma completes 0.5-2 full rotations in the experimental time frame (∼150 ns).

3.
Phys Rev Lett ; 129(22): 225001, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493430

RESUMEN

We present a study of perpendicular subcritical shocks in a collisional laboratory plasma. Shocks are produced by placing obstacles into the supermagnetosonic outflow from an inverse wire array z pinch. We demonstrate the existence of subcritical shocks in this regime and find that secondary shocks form in the downstream. Detailed measurements of the subcritical shock structure confirm the absence of a hydrodynamic jump. We calculate the classical (Spitzer) resistive diffusion length and show that it is approximately equal to the shock width. We measure little heating across the shock (<10% of the ion kinetic energy) which is consistent with an absence of viscous dissipation.

4.
Sci Rep ; 12(1): 18447, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36323877

RESUMEN

Resistance to anthracnose caused by the fungal pathogen Colletotrichum lentis was explored through transcriptome sequencing over a period of 24 to 96 h post-inoculation (hpi) of the partially resistant recombinant inbred lines (RIL) LR-66-528 and susceptible LR-66-524 of the crop wild relative Lens ervoides population LR-66. The development of infection vesicles and primary hyphae by C. lentis were significantly higher on susceptible RIL LR-66-524 compared to partially resistant LR-66-528 at 24 and 48 hpi, but exponential trends in fungal growth were observed between 24 to 96 hpi in both RILs. Comparison of inoculated with mock-inoculated samples revealed 3091 disease responsive genes, among which 477 were differentially expressed between the two RILs. These were clustered into six expression clusters with genes that had either high or low expression in one of the RILs. Differentially expressed genes (DEGs) were functionally annotated and included genes coding LRR and NB-ARC domain disease resistance proteins, protein detoxification, LRR receptor-like kinase family proteins, and wall-associated Ser/Thr Kinases. DEGs were compared to genes in previously published anthracnose resistance QTLs mapped in LR-66 and revealed 22 DEGs located in 3 QTLs. Expression of 21 DEGs was validated using RT-qPCR confirming expression trends in RNA-seq.


Asunto(s)
Colletotrichum , Fabaceae , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Colletotrichum/genética , Resistencia a la Enfermedad/genética , Sitios de Carácter Cuantitativo , Fabaceae/genética
5.
Hum Reprod ; 37(12): 2908-2920, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36166702

RESUMEN

STUDY QUESTION: Is the metabolic health of men conceived using ICSI different to that of IVF and spontaneously conceived (SC) men? SUMMARY ANSWER: ICSI-conceived men aged 18-24 years, compared with SC controls, showed differences in some metabolic parameters including higher resting diastolic blood pressure (BP) and homeostasis model assessment for insulin resistance (HOMA-IR) scores, although the metabolic parameters of ICSI- and IVF-conceived singleton men were more comparable. WHAT IS KNOWN ALREADY: Some studies suggest that IVF-conceived offspring may have poorer cardiovascular and metabolic profiles than SC children. Few studies have examined the metabolic health of ICSI-conceived offspring. STUDY DESIGN, SIZE, DURATION: This cohort study compared the metabolic health of ICSI-conceived men to IVF-conceived and SC controls who were derived from prior cohorts. Participants included 121 ICSI-conceived men (including 100 singletons), 74 IVF-conceived controls (all singletons) and 688 SC controls (including 662 singletons). PARTICIPANTS/MATERIALS, SETTING, METHODS: Resting systolic and diastolic BP (measured using an automated sphygmomanometer), height, weight, BMI, body surface area and fasting serum metabolic markers including fasting insulin, glucose, total cholesterol, high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol, triglycerides, highly sensitive C-reactive protein (hsCRP) and HOMA-IR were compared between groups. Data were analysed using multivariable linear regression adjusted for various covariates including age and education level. MAIN RESULTS AND THE ROLE OF CHANCE: After adjusting for covariates, compared to 688 SC controls, 121 ICSI-conceived men had higher diastolic BP (ß 4.9, 95% CI 1.1-8.7), lower fasting glucose (ß -0.7, 95% CI -0.9 to -0.5), higher fasting insulin (ratio 2.2, 95% CI 1.6-3.0), higher HOMA-IR (ratio 1.9, 95% CI 1.4-2.6), higher HDLC (ß 0.2, 95% CI 0.07-0.3) and lower hsCRP (ratio 0.4, 95% CI 0.2-0.7) levels. Compared to 74 IVF-conceived singletons, only glucose differed in the ICSI-conceived singleton men (ß -0.4, 95% CI -0.7 to -0.1). No differences were seen in the paternal infertility subgroups. LIMITATIONS, REASONS FOR CAUTION: The recruitment rate of ICSI-conceived men in this study was low and potential for recruitment bias exists. The ICSI-conceived men, the IVF-conceived men and SC controls were from different cohorts with different birth years and different geographical locations. Assessment of study groups and controls was not contemporaneous, and the measurements differed for some outcomes (BP, insulin, glucose, lipids and hsCRP). WIDER IMPLICATIONS OF THE FINDINGS: These observations require confirmation in a larger study with a focus on potential mechanisms. Further efforts to identify whether health differences are due to parental characteristics and/or factors related to the ICSI procedure are also necessary. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by an Australian National Health and Medical Research Council Partnership Grant (NHMRC APP1140706) and was partially funded by the Monash IVF Research and Education Foundation. S.R.C. was supported through an Australian Government Research Training Program Scholarship. R.J.H. is supported by an NHMRC project grant (634457), and J.H. and R.I.M. have been supported by the NHMRC as Senior and Principal Research Fellows respectively (J.H. fellowship number: 1021252; R.I.M. fellowship number: 1022327). L.R. is a minority shareholder and the Group Medical Director for Monash IVF Group, and reports personal fees from Monash IVF Group and Ferring Australia, honoraria from Ferring Australia and travel fees from Merck Serono and MSD and Guerbet; R.J.H. is the Medical Director of Fertility Specialists of Western Australia and has equity in Western IVF; R.I.M. is a consultant for and shareholder of Monash IVF Group and S.R.C. reports personal fees from Besins Healthcare and nonfinancial support from Merck outside of the submitted work. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Resistencia a la Insulina , Insulinas , Niño , Masculino , Humanos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Estudios de Cohortes , Proteína C-Reactiva , Australia , Semen , Glucosa , Colesterol , Fertilización In Vitro/métodos
6.
Rev Sci Instrum ; 92(3): 033521, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33820051

RESUMEN

We report on a recently developed laser-probing diagnostic, which allows direct measurements of ray-deflection angles in one axis while retaining imaging capabilities in the other axis. This allows us to measure the spectrum of angular deflections from a laser beam, which passes through a turbulent high-energy-density plasma. This spectrum contains information about the density fluctuations within the plasma, which deflect the probing laser over a range of angles. We create synthetic diagnostics using ray-tracing to compare this new diagnostic with standard shadowgraphy and schlieren imaging approaches, which demonstrates the enhanced sensitivity of this new diagnostic over standard techniques. We present experimental data from turbulence behind a reverse shock in a plasma and demonstrate that this technique can measure angular deflections between 0.06 and 34 mrad, corresponding to a dynamic range of over 500.

7.
Rev Sci Instrum ; 92(3): 033542, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33819991

RESUMEN

Optical collective Thomson scattering (TS) is used to diagnose magnetized high energy density physics experiments at the Magpie pulsed-power generator at Imperial College London. The system uses an amplified pulse from the second harmonic of a Nd:YAG laser (3 J, 8 ns, 532 nm) to probe a wide diversity of high-temperature plasma objects, with densities in the range of 1017-1019 cm-3 and temperatures between 10 eV and a few keV. The scattered light is collected from 100 µm-scale volumes within the plasmas, which are imaged onto optical fiber arrays. Multiple collection systems observe these volumes from different directions, providing simultaneous probing with different scattering K-vectors (and different associated α-parameters, typically in the range of 0.5-3), allowing independent measurements of separate velocity components of the bulk plasma flow. The fiber arrays are coupled to an imaging spectrometer with a gated intensified charge coupled device. The spectrometer is configured to view the ion-acoustic waves of the collective Thomson scattered spectrum. Fits to the spectra with the theoretical spectral density function S(K, ω) yield measurements of the local plasma temperatures and velocities. Fitting is constrained by independent measurements of the electron density from laser interferometry and the corresponding spectra for different scattering vectors. This TS diagnostic has been successfully implemented on a wide range of experiments, revealing temperature and flow velocity transitions across magnetized shocks, inside rotating plasma jets and imploding wire arrays, as well as providing direct measurements of drift velocities inside a magnetic reconnection current sheet.

8.
Hum Reprod Open ; 2020(4): hoaa042, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33033755

RESUMEN

STUDY QUESTIONS: What are the long-term health and reproductive outcomes for young men conceived using ICSI whose fathers had spermatogenic failure (STF)? Are there epigenetic consequences of ICSI conception? WHAT IS KNOWN ALREADY: Currently, little is known about the health of ICSI-conceived adults, and in particular the health and reproductive potential of ICSI-conceived men whose fathers had STF. Only one group to date has assessed semen parameters and reproductive hormones in ICSI-conceived men and suggested higher rates of impaired semen quality compared to spontaneously conceived (SC) peers. Metabolic parameters in this same cohort of men were mostly comparable. No study has yet evaluated other aspects of adult health. STUDY DESIGN SIZE DURATION: This cohort study aims to evaluate the general health and development (aim 1), fertility and metabolic parameters (aim 2) and epigenetic signatures (aim 3) of ICSI-conceived sons whose fathers had STF (ICSI study group). There are three age-matched control groups: ICSI-conceived sons whose fathers had obstructive azoospermia (OAZ) and who will be recruited in this study, as well as IVF sons and SC sons, recruited from other studies. Of 1112 ICSI parents including fathers with STF and OAZ, 78% (n = 867) of mothers and 74% (n = 823) of fathers were traced and contacted. Recruitment of ICSI sons started in March 2017 and will finish in July 2020. Based on preliminary participation rates, we estimate the following sample size will be achieved for the ICSI study group: mothers n = 275, fathers n = 225, sons n = 115. Per aim, the sample sizes of OAZ-ICSI (estimated), IVF and SC controls are: Aim 1-OAZ-ICSI: 28 (maternal surveys)/12 (son surveys), IVF: 352 (maternal surveys)/244 (son surveys), SC: 428 (maternal surveys)/255 (son surveys); Aim 2-OAZ-ICSI: 12, IVF: 72 (metabolic data), SC: 391 (metabolic data)/365 (reproductive data); Aim 3-OAZ-ICSI: 12, IVF: 71, SC: 292. PARTICIPANTS/MATERIALS SETTING METHODS: Eligible parents are those who underwent ICSI at one of two major infertility treatment centres in Victoria, Australia and gave birth to one or more males between January 1994 and January 2000. Eligible sons are those aged 18 years or older, whose fathers had STF or OAZ, and whose parents allow researchers to approach sons. IVF and SC controls are age-matched men derived from previous studies, some from the same source population. Participating ICSI parents and sons complete a questionnaire, the latter also undergoing a clinical assessment. Outcome measures include validated survey questions, physical examination (testicular volumes, BMI and resting blood pressure), reproductive hormones (testosterone, sex hormone-binding globulin, FSH, LH), serum metabolic parameters (fasting glucose, insulin, lipid profile, highly sensitive C-reactive protein) and semen analysis. For epigenetic and future genetic analyses, ICSI sons provide specimens of blood, saliva, sperm and seminal fluid while their parents provide a saliva sample. The primary outcomes of interest are the number of mother-reported hospitalisations of the son; son-reported quality of life; prevalence of moderate-severe oligozoospermia (sperm concentration <5 million/ml) and DNA methylation profile. For each outcome, differences between the ICSI study group and each control group will be investigated using multivariable linear and logistic regression for continuous and binary outcomes, respectively. Results will be presented as adjusted odds ratios and 95% CIs. STUDY FUNDING/COMPETING INTERESTS: This study is funded by an Australian National Health and Medical Research Council Partnership Grant (NHMRC APP1140706) and was partially funded by the Monash IVF Research and Education Foundation. L.R. is a minority shareholder and the Group Medical Director for Monash IVF Group, and reports personal fees from Monash IVF group and Ferring Australia, honoraria from Ferring Australia, and travel fees from Merck Serono, MSD and Guerbet; R.J.H. is the Medical Director of Fertility Specialists of Western Australia and has equity in Western IVF; R.I.M. is a consultant for and a shareholder of Monash IVF Group and S.R.C. reports personal fees from Besins Healthcare and non-financial support from Merck outside of the submitted work. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable. TRIAL REGISTRATION DATE: Not applicable. DATE OF FIRST PATIENT'S ENROLMENT: Not applicable.

10.
Ultrasound Obstet Gynecol ; 56(2): 215-224, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31625225

RESUMEN

OBJECTIVES: To perform individual record linkage of women undergoing screening with cell-free DNA (cfDNA), combined first-trimester screening (CFTS), second-trimester serum screening (STSS), and/or prenatal and postnatal cytogenetic testing with the aim to (1) obtain population-based estimates of utilization of prenatal screening and invasive diagnosis, (2) analyze the performance of different prenatal screening strategies, and (3) report the residual risk of any major chromosomal abnormality following a low-risk aneuploidy screening result. METHODS: This was a retrospective study of women residing in the state of Victoria, Australia, who underwent prenatal screening or invasive prenatal diagnosis in 2015. Patient-funded cfDNA referrals from multiple providers were merged with state-wide results for government-subsidized CFTS, STSS and invasive diagnostic procedures. Postnatal cytogenetic results from products of conception and infants up to 12 months of age were obtained to ascertain cases of false-negative screening results and atypical chromosomal abnormalities. Individual record linkage was performed using LinkageWizTM . RESULTS: During the study period, there were 79 140 births and 66 166 (83.6%) women underwent at least one form of aneuploidy screening. Linkage data were complete for 93.5% (n = 61 877) of women who underwent screening, and of these, 73.2% (n = 45 275) had CFTS alone, 20.2% (n = 12 486) had cfDNA alone; 5.3% (n = 3268) had STSS alone, 1.3% (n = 813) had both CFTS and cfDNA, and < 0.1% (n = 35) had both STSS and cfDNA. CFTS had a combined sensitivity for trisomies 21 (T21), 18 (T18) and 13 (T13) of 89.57% (95% CI, 82.64-93.93%) for a screen-positive rate (SPR) of 2.94%. There were 12 false-negative results in the CFTS pathway, comprising 10 cases of T21, one of T18 and one of T13. cfDNA had a combined sensitivity for T21, T18 and T13 of 100% (95% CI, 95.00-100%) for a SPR of 1.21%. When high-risk cfDNA results for any chromosome (including the sex chromosomes) and failed cfDNA tests were treated as screen positives, the SPR for cfDNA increased to 2.42%. The risk of any major chromosomal abnormality (including atypical abnormalities) detected on prenatal or postnatal diagnostic testing after a low-risk screening result was 1 in 1188 for CFTS (n = 37) and 1 in 762 for cfDNA (n = 16) (P = 0.13). The range of chromosomal abnormalities detected after a low-risk cfDNA result included pathogenic copy-number variants (n = 6), triploidy (n = 3), rare autosomal trisomies (n = 3) and monosomy X (n = 2). CONCLUSIONS: Our state-wide record-linkage analysis delineated the utilization and clinical performance of the multitude of prenatal screening pathways available to pregnant women. The sensitivity of cfDNA for T21, T18 and T13 was clearly superior to that of CFTS. While there was no statistically significant difference in the residual risk of any major chromosomal abnormality after a low-risk CFTS or cfDNA result, there were fewer live infants diagnosed with a major chromosomal abnormality in the cfDNA cohort. These data provide valuable population-based evidence to inform practice recommendations and health policies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Ácidos Nucleicos Libres de Células , Aberraciones Cromosómicas/embriología , Trastornos de los Cromosomas/diagnóstico , Pruebas Genéticas/estadística & datos numéricos , Diagnóstico Prenatal/estadística & datos numéricos , Adulto , Aneuploidia , Trastornos de los Cromosomas/embriología , Análisis Citogenético/métodos , Análisis Citogenético/estadística & datos numéricos , Reacciones Falso Negativas , Femenino , Pruebas Genéticas/métodos , Humanos , Registro Médico Coordinado , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo/genética , Diagnóstico Prenatal/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad , Victoria
12.
Ultrasound Obstet Gynecol ; 53(4): 503-511, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29877030

RESUMEN

OBJECTIVE: To assess trends in ultrasound-indicated prenatal diagnostic testing performed over the past two decades in the Australian state of Victoria, in the context of rapidly changing practices in aneuploidy screening and chromosome analysis. METHODS: This was a retrospective analysis of all ultrasound-indicated prenatal diagnostic testing (amniocentesis and chorionic villus sampling) performed in the state of Victoria between 1994 and 2016. Ultrasound indications for testing included: fetal structural abnormality, fetal death, fetal growth restriction, abnormal amniotic fluid volume, genetic 'soft marker' and unspecified ultrasound abnormality. Maternal age, indication for testing, type of diagnostic procedure, gestational age, type of chromosome analysis (G-banded karyotyping or chromosomal microarray (CMA)) and test results were obtained. Diagnostic yield (i.e. percentage of tests yielding a major abnormality) was analyzed by year, maternal age and gestational age. Statistical analysis was performed using the χ2 tests for trend or difference in proportions, as appropriate. RESULTS: During the 23-year study period, 1 533 317 births were recorded and 16 152 diagnostic procedures were performed for the primary indication of ultrasound abnormality. In recent years, ultrasound abnormality became the most common indication for prenatal invasive testing (29.4% of diagnostic tests between 2013 and 2016) due to a steep decline in testing for other indications such as positive result on combined first-trimester screening or advanced maternal age alone. In 2016, over 95% of ultrasound-indicated procedures were performed with CMA; among these, pathogenic copy number variant (CNV) was the most common (3.5%) abnormality detected, followed by trisomy 21 (2.8%). The diagnostic yield of ultrasound-indicated tests performed < 16 weeks was significantly higher than that of tests performed after 20 weeks (31.5% vs 9.0%). CONCLUSIONS: Ultrasound-indicated invasive testing is contributing to prenatal diagnosis in new ways in the genomic era. A pathogenic CNV is now the most likely diagnosis after ultrasound-indicated testing, rather than trisomy 21 or other whole-chromosome aneuploidy. Despite steady improvements in first-trimester screening for aneuploidy, the diagnostic yield of ultrasound-indicated tests > 20 weeks has remained stable due to increased utilization of CMA. Procedures performed for structural abnormalities < 16 weeks continue to have the highest diagnostic yield, supporting the benefits of early fetal structural assessment at 11-13 weeks. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Amniocentesis/estadística & datos numéricos , Muestra de la Vellosidad Coriónica/estadística & datos numéricos , Ultrasonografía Prenatal/estadística & datos numéricos , Adulto , Aneuploidia , Ácidos Nucleicos Libres de Células , Variaciones en el Número de Copia de ADN , Síndrome de Down/diagnóstico , Femenino , Humanos , Edad Materna , Vigilancia de la Población , Embarazo , Estudios Retrospectivos , Victoria
13.
Andrology ; 6(5): 635-653, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30296010

RESUMEN

BACKGROUND: A significant increase in the use of intracytoplasmic sperm injection (ICSI) since its introduction in 1992 has been observed worldwide, including beyond its original intended use for severe male factor infertility. Concerns regarding ICSI include the effects of poor quality spermatozoa on offspring health and future fertility, and of the technique itself. The health and development of ICSI-conceived children beyond early infancy have not been comprehensively assessed. OBJECTIVE: A systematic review of health outcomes of ICSI-conceived offspring beyond the neonatal period compared to spontaneously conceived (SC) offspring. DESIGN: PubMed, OVID Medline/Embase, InformIT, Web of Science, and ProQuest databases were searched for studies reporting on health outcomes in ICSI-conceived offspring beyond 28 days after birth. MAIN OUTCOMES MEASURE(S): Physical and psychosocial health. RESULTS: The search strategy yielded 2826 articles. Of these, 2580 were not relevant or did not meet inclusion criteria and 138 were duplicates. One hundred and eight full-text papers were evaluated further, and 48 satisfied the inclusion criteria. Most studies reported on neurodevelopment during early infancy and childhood with reassuring results. Growth, vision, and hearing of ICSI and SC offspring also appear comparable, although important differences in general physical health, and particularly metabolic and reproductive health have been described, including recently poorer semen quality among ICSI-conceived young adult men compared to SC peers. CONCLUSION: Whilst neurodevelopment, growth, vision, and hearing appear similar between ICSI and SC children, evidence suggests differences in general physical health, and metabolic and reproductive endpoints. The clinical significance of many findings, however, remains unclear, and further prospective, large, and good quality studies with a focus on all these health outcomes in ICSI-conceived young adults are required.


Asunto(s)
Desarrollo Infantil , Inyecciones de Esperma Intracitoplasmáticas , Niño , Preescolar , Estudios de Seguimiento , Estado de Salud , Humanos , Lactante , Sistema Nervioso/crecimiento & desarrollo , Evaluación del Resultado de la Atención al Paciente
14.
Ultrasound Obstet Gynecol ; 51(4): 487-492, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29226487

RESUMEN

OBJECTIVES: To investigate by means of a population-based analysis of a cohort of women who underwent combined first-trimester screening (CFTS), changes in uptake of invasive prenatal diagnosis according to risk of trisomy 21 (T21) on CFTS, and prevalence and methods for ascertainment of atypical chromosome abnormalities. METHODS: This was a retrospective cohort study using state-wide prenatal datasets from Victoria, Australia. A three-step approach was taken to analyze the data: (1) linkage of records between serum screening and diagnostic results; (2) comparison of rates of diagnostic testing according to CFTS T21 risk result category in a 2014-2015 cohort with those of a historical 2002-2004 cohort; (3) detailed analysis of atypical abnormalities in the 2014-2015 group according to CFTS T21 risk result, individual serum analyte level and other indications for invasive diagnostic testing. RESULTS: In 2014-2015, there were 100 418 CFTS results issued for 146 776 births (68.4%). The overall prevalence of atypical chromosome abnormalities in the entire CFTS cohort was 0.10% and was highest in those with CFTS T21 risk > 1 in 10 (4.6%), or serum analyte levels < 0.2 multiples of the median (MoM) (6.9% for pregnancy-associated plasma protein-A (PAPP-A) and 5.2% for beta-human chorionic gonadotropin (ß-hCG)). Almost half (49.2%) of women with PAPP-A < 0.2 MoM had a risk for T21 on CFTS of less than 1 in 100. The majority (55%) of atypical abnormalities occurred in women with CFTS T21 risk below 1 in 300, and were most commonly detected on ultrasound examination (47.1%). CONCLUSION: Concerns regarding missed diagnoses of atypical chromosome abnormalities when non-invasive prenatal testing is offered after a result of high risk on CFTS can be mitigated if invasive diagnostic testing is offered to those women with CFTS T21 risk of > 1 in 100, serum PAPP-A or ß-hCG < 0.2 MoM, or ultrasound-detected abnormality. This has implications for contingent models of screening. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Síndrome de Down/diagnóstico , Síndrome de Down/genética , Pruebas de Detección del Suero Materno/estadística & datos numéricos , Ultrasonografía Prenatal/estadística & datos numéricos , Adulto , Gonadotropina Coriónica Humana de Subunidad beta/sangre , Variaciones en el Número de Copia de ADN/genética , Síndrome de Down/sangre , Síndrome de Down/epidemiología , Femenino , Humanos , Tamizaje Masivo/estadística & datos numéricos , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo , Proteína Plasmática A Asociada al Embarazo/análisis , Prevalencia , Estudios Retrospectivos , Medición de Riesgo , Victoria/epidemiología
15.
Philos Trans R Soc Lond B Biol Sci ; 372(1725)2017 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-28584176

RESUMEN

Emerging zoonoses with pandemic potential are a stated priority for the global health security agenda, but endemic zoonoses also have a major societal impact in low-resource settings. Although many endemic zoonoses can be treated, timely diagnosis and appropriate clinical management of human cases is often challenging. Preventive 'One Health' interventions, e.g. interventions in animal populations that generate human health benefits, may provide a useful approach to overcoming some of these challenges. Effective strategies, such as animal vaccination, already exist for the prevention, control and elimination of many endemic zoonoses, including rabies, and several livestock zoonoses (e.g. brucellosis, leptospirosis, Q fever) that are important causes of human febrile illness and livestock productivity losses in low- and middle-income countries. We make the case that, for these diseases, One Health interventions have the potential to be more effective and generate more equitable benefits for human health and livelihoods, particularly in rural areas, than approaches that rely exclusively on treatment of human cases. We hypothesize that applying One Health interventions to tackle these health challenges will help to build trust, community engagement and cross-sectoral collaboration, which will in turn strengthen the capacity of fragile health systems to respond to the threat of emerging zoonoses and other future health challenges. One Health interventions thus have the potential to align the ongoing needs of disadvantaged communities with the concerns of the broader global community, providing a pragmatic and equitable approach to meeting the global goals for sustainable development and supporting the global health security agenda.This article is part of the themed issue 'One Health for a changing world: zoonoses, ecosystems and human well-being'.


Asunto(s)
Países en Desarrollo , Salud Global , Salud Única , Zoonosis/prevención & control , Animales , Humanos
16.
Andrology ; 5(4): 610-621, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28632930

RESUMEN

The use of intra-cytoplasmic sperm injection (ICSI) has increased significantly worldwide, often chosen instead of in vitro fertilization (IVF), yet long-term health outcomes are unknown and health differences between ICSI and IVF conceptions have not been comprehensively assessed. A systematic review of health outcomes of ICSI-conceived offspring beyond the neonatal period compared to IVF-conceived offspring was carried out. PubMed, OVID Medline/Embase, Informit, Web of Science and Proquest databases were searched on 9 November 2016 for studies reporting on health outcomes in ICSI-conceived offspring beyond 28 days after birth. Physical and psychosocial health were the main outcome measures. The search strategy yielded 2781 articles; 2539 were not relevant or did not meet inclusion criteria and 137 were duplicates. One hundred and five full-text papers were evaluated further and 34 satisfied the inclusion criteria. Studies comparing ICSI- and IVF-conceived children suggest their neurodevelopment is comparable. Growth and aspects of physical health are also similar; however, studies are few and limited to childhood. ICSI-conceived children may be at increased risk of autism and intellectual impairment. No difference in risk of childhood cancer was reported in one study. Whilst the neurodevelopment of ICSI-conceived children appears comparable to those of IVF conception, data relating to neurodevelopmental disorders, growth, physical health and childhood cancer are inconclusive. Further research into health outcomes in adolescence and adulthood is required before conclusions can be drawn about the long-term safety of ICSI compared to IVF. Until then, ICSI might be better reserved for its original intended use, male-factor infertility.


Asunto(s)
Desarrollo Infantil , Fertilización In Vitro , Infertilidad/terapia , Inyecciones de Esperma Intracitoplasmáticas , Factores de Edad , Trastorno Autístico/etiología , Niño , Preescolar , Discapacidades del Desarrollo/etiología , Femenino , Fertilidad , Fertilización In Vitro/efectos adversos , Estado de Salud , Humanos , Lactante , Recién Nacido , Infertilidad/diagnóstico , Infertilidad/fisiopatología , Nacimiento Vivo , Masculino , Neoplasias/etiología , Embarazo , Medición de Riesgo , Factores de Riesgo , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
17.
BMC Public Health ; 15: 707, 2016 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-27487945

RESUMEN

BACKGROUND: Although childhood obesity prevalence is stabilised in developed countries including Australia, it is continuing to rise among migrants and socially disadvantaged groups in these countries. African migrants and refugees in particular, are at high risk of obesity due to changes in their family dynamics. The aim of this study was to examine the difference between children and parental perception of family functioning, family communication, family type and parenting styles and their relationship with body mass index. METHODS: A cross-sectional parent-child dyad study was conducted among 284 African families from migrant and refugee backgrounds living in metropolitan Melbourne, Australia. Bilingual workers were trained to collect demographic, anthropometric and questionnaire data on family functioning, parenting, family type and family communication. RESULTS: Parents and children reported different levels of family dynamics. Children reported a higher prevalence of poor family functioning (61.5 %, 95 % CI: 55.6, 67.2 versus 56.8 %, 95 % CI: 49.7, 61.6) and protective family type (29 %, 95 % CI: 23.9, 34.5 vs. 13.4 %, 95 % CI: 9.9, 17.9), but a lower prevalence of authoritative parenting style (51.6 %, 95 % CI: 45.7, 57.5 vs. 63 %, 95 % CI: 57.5, 68.8) than parents. There was a positive relationship between poor family functioning and child BMI both before (ß = 1.28; 95 % CI: 0.14, 2.41; p < 0.05) and after (ß = 1.73; 95 % CI: 0.53, 2.94; p < 0.001) controlling for confounders, and an inverse relationship between consensual family type and child BMI after adjustment (ß = -1.92; 95 % CI: -3.59, -0.24; p < 0.05). There was no significant relationship between parental BMI and family functioning, communication, family type or parenting style. CONCLUSION: Children's perception of poor family functioning was associated with childhood obesity. Family interventions to reduce childhood obesity need to adopt an intergenerational approach to promote a clear understanding of family dynamics between children and parents. Unless these intergenerational challenges associated with family dynamics are clearly addressed in obesity interventions, current obesity prevention initiatives will continue to widen the childhood obesity gap in Australia.


Asunto(s)
Población Negra , Índice de Masa Corporal , Comunicación , Emigrantes e Inmigrantes , Relaciones Padres-Hijo , Responsabilidad Parental , Obesidad Infantil/etnología , Aculturación , Adolescente , Adulto , África , Concienciación , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Padres , Obesidad Infantil/etiología , Prevalencia , Encuestas y Cuestionarios , Migrantes , Victoria
18.
BJOG ; 123(1): 90-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26108969

RESUMEN

OBJECTIVE: To analyse population-based trends over the entire history of prenatal testing for aneuploidy. DESIGN: Retrospective analysis of state-wide data sets. SETTING: Australian state of Victoria with ~70 000 annual births. POPULATION: All pregnant women undergoing invasive prenatal testing at <25 weeks' gestation from 1976 to 2013. METHODS: Analysis of three state-wide data sets: (1) Prenatal diagnosis data set of 119 404 amniocenteses and chorionic villus samplings from 1976 to 2013; (2) central serum screening laboratory data set from 1996 to 2013; (3) government birth statistics from 1976 to 2013. MAIN OUTCOME MEASURES: Annual numbers and uptake rates of invasive prenatal tests and serum screening, indications for invasive prenatal testing, prenatal diagnoses of aneuploidy, diagnostic yield of invasive tests. RESULTS: Annual numbers of invasive prenatal tests climbed steadily from 1976, then declined from 2000. In 2013, the number of invasive prenatal tests was the lowest in 25 years, while the number of trisomy 21 diagnoses was the highest ever recorded. Annual uptake of serum screening climbed from 1.6 to 83% over 1996-2013. Results from 2013 showed a high diagnostic yield (15.8%) for a low rate of invasive testing (3.4% of births). Over four decades, the number of invasive procedures performed for each diagnosis of major chromosome abnormality declined from 100 to six. CONCLUSIONS: This study demonstrates historic reductions in the proportion of women undergoing invasive testing and dramatic improvements in diagnostic yield. Monitoring the impact of new prenatal technologies on this progress remains an important research priority. TWEETABLE ABSTRACT: Invasive prenatal testing has reached historic lows due to dramatic improvements in Down syndrome screening.


Asunto(s)
Aborto Espontáneo/prevención & control , Síndrome de Down/diagnóstico , Pruebas Genéticas , Medida de Translucencia Nucal/métodos , Diagnóstico Prenatal , Adulto , Amniocentesis/efectos adversos , Australia/epidemiología , Biomarcadores/metabolismo , Gonadotropina Coriónica Humana de Subunidad beta/metabolismo , Síndrome de Down/epidemiología , Síndrome de Down/metabolismo , Femenino , Edad Gestacional , Humanos , Recién Nacido , Edad Materna , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Proteína Plasmática A Asociada al Embarazo/metabolismo , Estudios Retrospectivos , Victoria/epidemiología , alfa-Fetoproteínas/metabolismo
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