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1.
Cell Mol Life Sci ; 81(1): 196, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658440

RESUMO

Telomeres as the protective ends of linear chromosomes, are synthesized by the enzyme telomerase (TERT). Critically short telomeres essentially contribute to aging-related diseases and are associated with a broad spectrum of disorders known as telomeropathies. In cardiomyocytes, telomere length is strongly correlated with cardiomyopathies but it remains ambiguous whether short telomeres are the cause or the result of the disease. In this study, we employed an inducible CRISPRi human induced pluripotent stem cell (hiPSC) line to silence TERT expression enabling the generation of hiPSCs and hiPSC-derived cardiomyocytes with long and short telomeres. Reduced telomerase activity and shorter telomere lengths of hiPSCs induced global transcriptomic changes associated with cardiac developmental pathways. Consequently, the differentiation potential towards cardiomyocytes was strongly impaired and single cell RNA sequencing revealed a shift towards a more smooth muscle cell like identity in the cells with the shortest telomeres. Poor cardiomyocyte function and increased sensitivity to stress directly correlated with the extent of telomere shortening. Collectively our data demonstrates a TERT dependent cardiomyogenic differentiation defect, highlighting the CRISPRi TERT hiPSCs model as a powerful platform to study the mechanisms and consequences of short telomeres in the heart and also in the context of telomeropathies.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Telomerase , Telômero , Telomerase/metabolismo , Telomerase/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Telômero/metabolismo , Encurtamento do Telômero , Linhagem Celular
2.
J Am Chem Soc ; 146(13): 9224-9229, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517326

RESUMO

Ligand-based functionalization strategies have emerged as powerful approaches to tune and optimize blue phosphorescence, which can involve nucleophilic addition to coordinated ligands or electrophilic functionalization via the coordination of exogenous Lewis acids. Whereas both have been used separately to enhance the photophysical properties of organometallic compounds with high-energy triplet states, in this work, we show that these two strategies can be used together on the same platform. Isocyanide-supported cyclometalated platinum compounds undergo nucleophilic addition with diethylamine to form a strong σ-donor acyclic diaminocarbene-supporting ligand. In a subsequent step, a cyanide ancillary ligand is converted into a more strongly π-acidic isocyanoborate via the coordination of a borane Lewis acid. Importantly, both of these ligand-based functionalization steps improve the quantum yields and lifetimes of the blue-phosphorescent complexes. This synergy results in complexes with photoluminescence quantum yields up to 0.40 for deep blue and 0.75 for sky blue regions and PL lifetimes on the order of 10-5 s.

3.
Inorg Chem ; 62(41): 16759-16769, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37782937

RESUMO

One of the main challenges in developing effective copper(I) photosensitizers is their short excited-state lifetimes, usually attributed to structural distortion upon light excitation. We have previously introduced copper(I) charge-transfer chromophores of the general formula Cu(N^N)(ArNacNac), where N^N is a conjugated diimine ligand and ArNacNac is a substituted ß-diketiminate ligand. These chromophores were promising regarding their tunable redox potentials and intense visible absorption but were ineffective as photosensitizers, presumably due to short excited-state lifetimes. Here, we introduce sterically crowded analogues of these heteroleptic chromophores with bulky alkyl substituents on the N^N and/or ArNacNac ligand. Structural analysis was combined with electrochemical and photophysical characterization, including ultrafast transient absorption (UFTA) spectroscopy to investigate the effects of the alkyl groups on the excited-state lifetimes of the complexes. The molecular structures determined by single-crystal X-ray diffraction display more distortion in the ground state as alkyl substituents are introduced into the phenanthroline or the NacNac ligand, showing smaller τ4 values due to the steric hindrance. UFTA measurements were carried out to determine the excited-state dynamics. Sterically encumbered Cu5 and Cu6 display excited-state lifetimes 15-20 times longer than unsubstituted complex Cu1, likely indicating that the incorporation of bulky alkyl substituents inhibits the pseudo-Jahn-Teller (PJT) flattening distortion in the excited state. This work suggests that the steric properties of these heteroleptic copper(I) charge-transfer chromophores can be readily modified and that the excited-state dynamics are strongly responsive to these modifications.

4.
Cochrane Database Syst Rev ; 8: CD001301, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37581383

RESUMO

BACKGROUND: Starting over 40 years ago, in vitro fertilisation (IVF) has become the cornerstone for fertility treatment. Since then, in 1992, Palermo and colleagues successfully applied the technique intracytoplasmic sperm injection (ICSI) to benefit couples where conventional in vitro fertilisation (c-IVF) and sub-zonal insemination (SUZI) proved unsuccessful. After this case report, ICSI has become the treatment of choice for couples with severe male factor subfertility. Over time, ICSI has been used in the treatment of couples with mild male and even unexplained infertility. This review is an update of the review, first published in 1999, comparing ICSI with c-IVF for couples with males presenting with normal total sperm count and motility. OBJECTIVES: To evaluate the effectiveness and safety of ICSI relative to c-IVF in couples with males presenting with normal total sperm count and motility. SEARCH METHODS: We searched the following databases and trial registers: Cochrane Central Register of Controlled Trials (CENTRAL), Embase (excerpta Medica Database), MEDLINE (Medical Literature Analysis and Retrieval System Online) and PsycINFO (Psychological literature database) for articles between January 2010 and 22 February 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared ICSI with c-IVF in couples with males presenting with normal total sperm count and motility. DATA COLLECTION AND ANALYSIS: We used standard methodical procedures recommended by Cochrane. The primary review outcomes were live birth and adverse events. Secondary outcomes included clinical pregnancy, viable intrauterine pregnancy and miscarriage. MAIN RESULTS: The original review published in 2003 included one RCT. In this 2023 update, we identified an additional two RCTs totalling a cohort of 1539 couples, comparing ICSI with c-IVF techniques. Two studies reported on live birth. Using the GRADE method, we assessed the certainty of evidence and reported evidence as low-certainty for live birth. We are uncertain of the effect of ICSI versus c-IVF for live birth rates (risk ratio (RR) 1.11, 95% confidence interval (CI 0.94 to 1.30, I2 = 0%, 2 studies, n = 1124, low-certainty evidence). The evidence suggests that if the chance of live birth following c-IVF is assumed to be 32%, the chance of live birth with ICSI would be between 30% and 41%. For adverse events; multiple pregnancy, ectopic pregnancy, pre-eclampsia and prematurity, there was probably little or no difference between the two techniques. No study reported the primary outcome stillbirth. For secondary outcomes, we are uncertain of the effect of ICSI versus c-IVF for clinical pregnancy rates (RR 1.00, 95% CI 0.88 to 1.13, I2 = 45%, 3 studies, n = 1539, low-certainty evidence). Comparison of viable intrauterine pregnancy rates showed probably little or no difference between ICSI and c-IVF (RR 1.00, 95% CI 0.86 to 1.16, I2=75%, 2 studies, n = 1479 couples, moderate-certainty evidence). The high heterogeneity may have been caused by one older study conducted when protocols were less rigorous. The evidence suggests that if the chance of viable intrauterine pregnancy following c-IVF is assumed to be 33%, the chance of viable intrauterine pregnancy with ICSI would be between 28% and 38%. Miscarriage rates also showed probably little or no difference between the two techniques. AUTHORS' CONCLUSIONS: The current available studies that compare ICSI and c-IVF in couples with males presenting with normal total sperm count and motility, show neither method was superior to the other, in achieving live birth, adverse events (multiple pregnancy, ectopic pregnancy, pre-eclampsia and prematurity), also alongside secondary outcomes, clinical pregnancy, viable intrauterine pregnancy or miscarriage.


Assuntos
Aborto Espontâneo , Pré-Eclâmpsia , Gravidez Ectópica , Feminino , Humanos , Masculino , Gravidez , Aborto Espontâneo/epidemiologia , Fertilização in vitro/métodos , Nascido Vivo/epidemiologia , Taxa de Gravidez , Contagem de Espermatozoides , Injeções de Esperma Intracitoplásmicas/métodos
5.
Acta Obstet Gynecol Scand ; 102(5): 626-634, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36905390

RESUMO

INTRODUCTION: Preterm birth is the most common cause of neonatal morbidity and mortality. Women with twin pregnancies and a short cervical length are at high risk for preterm birth. Vaginal progesterone and cervical pessary have been proposed as potential strategies to reduce preterm birth in this high-risk population. Therefore, we aimed to compare the effectiveness of cervical pessary and vaginal progesterone in improving developmental outcomes of children born to women with twin pregnancies and mid-trimester short cervical length. MATERIAL AND METHODS: This was a follow-up study (NCT04295187) of all children at 24 months of age, born from women treated with cervical pessary or progesterone to prevent preterm birth in a randomized controlled trial (NCT02623881). We used a validated Vietnamese version of Ages & Stages Third Edition Questionnaires (ASQ-3) and a red flag questionnaire. In surviving children, we compared the mean ASQ-3 scores, abnormal ASQ-3 scores, the number of children with any abnormal ASQ-3 scores and red flag signs between the two groups. We reported the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in offspring. These outcomes were also calculated in a subgroup of women with a cervical length ≤28 mm (<25th percentile). RESULTS: In the original randomized controlled trial, we randomized 300 women to pessary or progesterone. After counting the number of perinatal deaths and lost to follow-up, 82.8% parents in the pessary group and 82.5% parents in progesterone group returned the questionnaire. The mean ASQ-3 scores of the five skills and red flag signs did not differ significantly between the two groups. However, the percentage of children having abnormal ASQ-3 scores in fine motor skills was significantly lower in the progesterone group (6.1% vs 1.3%, P = 0.01). There were no significant differences in the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in unselected women and in those with cervical length ≤28 mm. CONCLUSIONS: Cervical pessary and vaginal progesterone may have comparable effects on developmental outcomes in children at ≥24 months of age, born to women with twin pregnancies and short cervical length. However, this finding could be likely due to a lack of study power.


Assuntos
Morte Perinatal , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Criança , Humanos , Progesterona , Gravidez de Gêmeos , Seguimentos , Nascimento Prematuro/prevenção & controle , Pessários , Colo do Útero , Administração Intravaginal
6.
Am J Perinatol ; 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429323

RESUMO

OBJECTIVE: Preterm birth, defined as birth before 37 weeks of gestation, is a leading cause of perinatal and infant mortality throughout the world. Preterm birth is also associated with long-term neurological disabilities and other significant health issues in children. A short cervix in the second trimester has been noted to be one of the strongest predictors of subsequent spontaneous preterm birth in both singleton and multiple pregnancies. Some studies have shown that cervical support in the form of an Arabin pessary lowers the risk of preterm birth in women with a singleton gestation and short cervical length; however, other studies have conflicting results. Our objective was to form an international collaborative of planned or ongoing randomized trials of pessary in singleton and twin gestations with a short cervix. STUDY DESIGN: In November 2014, an international group of investigators, who had initiated or were planning randomized trials of pessary for pregnant people with a short cervix and singleton or twin gestation to prevent preterm birth, formed a collaboration to plan a prospective individual patient data (IPD) meta-analysis of randomized trials (PROspective Meta-analysis of Pessary Trials [PROMPT]). The PROMPT investigators agreed on meta-analysis IPD hypotheses for singletons and twins, eligibility criteria, and a set of core baseline and outcome measures. The primary outcome is a composite of fetal death or preterm delivery before 32 weeks' gestation. Secondary outcomes include maternal and neonatal morbidities. The PROMPT protocol may be viewed as a written agreement among the study investigators who make up the PROMPT consortium (PROSPERO ID# CRD42018067740). RESULTS: Results will be published in phases as the individual participating studies are concluded and published. Results of the first phase of singleton and twin pessary trials are expected to be available in late 2022. Updates are planned as participating trials are completed and published. KEY POINTS: · Short cervical length predicts preterm birth.. · Results of prior cervical pessary trials are mixed.. · Meta-analysis of pessary trials protocol..

7.
Lancet ; 397(10284): 1554-1563, 2021 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33894833

RESUMO

BACKGROUND: The use of intracytoplasmic sperm injection has increased substantially worldwide, primarily in couples with non-male factor infertility. However, there is a paucity of evidence from randomised trials supporting this approach compared with conventional in-vitro fertilisation (IVF). We aimed to investigate whether intracytoplasmic sperm injection would result in a higher livebirth rate compared with conventional IVF. METHODS: This open-label, multicentre, randomised trial was done at two IVF centres in Ho Chi Minh City, Vietnam (IVFMD, My Duc Hospital and IVFAS, An Sinh Hospital). Eligible couples were aged at least 18 years and the male partner's sperm count and motility (progressive motility) were normal based on WHO 2010 criteria. Couples had to have undergone two or fewer previous conventional IVF or intracytoplasmic sperm injection attempts, have used an antagonist protocol for ovarian stimulation, and agree to have two or fewer embryos transferred. Couples were randomly assigned (1:1) to undergo either intracytoplasmic sperm injection or conventional IVF, using block randomisation with variable block size of 2, 4, or 8 and a telephone-based central randomisation method. The computer-generated randomisation list was prepared by an independent statistician who had no other involvement in the study. Embryologists and couples were not masked to study groups because of the type of interventions and differences in hospital fees, but clinicians performing embryo transfer were unaware of study group allocation. The primary outcome was livebirth after the first embryo transfer from the initiated cycle. Analyses were done on an intention-to-treat basis. The trial is registered with ClinicalTrials.gov, NCT03428919. FINDINGS: Between March 16, 2018, and Aug 12, 2019, we randomly assigned 1064 couples to intracytoplasmic sperm injection (n=532) or conventional IVF (n=532). Livebirth after the first embryo transfer from the initiated cycle occurred in 184 (35%) of 532 couples randomly assigned to intracytoplasmic sperm injection and in 166 (31%) of 532 couples randomly assigned to conventional IVF (absolute difference 3·4%, 95% CI -2·4 to 9·2; risk ratio [RR] 1·11, 95% CI 0·93 to 1·32; p=0·27). 29 (5%) couples in the intracytoplasmic sperm injection group and 34 (6%) couples in the conventional IVF group had fertilisation failure (absolute difference -0·9%, -4·0 to 2·1, RR 0·85, 95% CI 0·53 to 1·38; p=0·60). INTERPRETATION: In couples with infertility in whom the male partner has a normal total sperm count and motility, intracytoplasmic sperm injection did not improve the livebirth rate compared with conventional IVF. Our results challenge the value of the routine use of intracytoplasmic sperm injection in assisted reproduction techniques for this population. FUNDING: My Duc Hospital and Merck Sharp and Dohme.


Assuntos
Fertilização in vitro/efeitos adversos , Infertilidade/terapia , Técnicas de Reprodução Assistida/estatística & dados numéricos , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Adulto , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Humanos , Análise de Intenção de Tratamento/métodos , Nascido Vivo/epidemiologia , Masculino , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Técnicas de Reprodução Assistida/tendências , Contagem de Espermatozoides/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Motilidade dos Espermatozoides/fisiologia , Vietnã/epidemiologia
8.
Blood ; 136(19): 2162-2174, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32589707

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening hyperinflammatory syndromes typically associated with underlying hematologic and rheumatic diseases, respectively. Familial HLH is associated with genetic cytotoxic impairment and thereby to excessive antigen presentation. Extreme elevation of serum interleukin-18 (IL-18) has been observed specifically in patients with MAS, making it a promising therapeutic target, but how IL-18 promotes hyperinflammation remains unknown. In an adjuvant-induced MAS model, excess IL-18 promoted immunopathology, whereas perforin deficiency had no effect. To determine the effects of excess IL-18 on virus-induced immunopathology, we infected Il18-transgenic (Il18tg) mice with lymphocytic choriomeningitis virus (LCMV; strain Armstrong). LCMV infection is self-limited in wild-type mice, but Prf1-/- mice develop prolonged viremia and fatal HLH. LCMV-infected Il18-transgenic (Il18tg) mice developed cachexia and hyperinflammation comparable to Prf1-/- mice, albeit with minimal mortality. Like Prf1-/- mice, immunopathology was largely rescued by CD8 depletion or interferon-γ (IFNg) blockade. Unlike Prf1-/- mice, they showed normal target cell killing and normal clearance of viral RNA and antigens. Rather than impairing cytotoxicity, excess IL-18 acted on T lymphocytes to amplify their inflammatory responses. Surprisingly, combined perforin deficiency and transgenic IL-18 production caused spontaneous hyperinflammation specifically characterized by CD8 T-cell expansion and improved by IFNg blockade. Even Il18tg;Prf1-haplosufficient mice demonstrated hyperinflammatory features. Thus, excess IL-18 promotes hyperinflammation via an autoinflammatory mechanism distinct from, and synergistic with, cytotoxic impairment. These data establish IL-18 as a potent, independent, and modifiable driver of life-threatening innate and adaptive hyperinflammation and support the rationale for an IL-18-driven subclass of hyperinflammation.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Interleucina-18/metabolismo , Coriomeningite Linfocítica/complicações , Vírus da Coriomeningite Linfocítica/patogenicidade , Perforina/fisiologia , Animais , Feminino , Inflamação/etiologia , Inflamação/metabolismo , Interferon gama/metabolismo , Interleucina-18/genética , Ativação Linfocitária , Coriomeningite Linfocítica/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
9.
N Engl J Med ; 378(2): 137-147, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29320655

RESUMO

BACKGROUND: Among women who are undergoing in vitro fertilization (IVF), the transfer of frozen embryos has been shown to result in a higher rate of live birth than the transfer of fresh embryos in those with infertility associated with the polycystic ovary syndrome. It is not known whether frozen-embryo transfer results in similar benefit in women with infertility that is not associated with the polycystic ovary syndrome. METHODS: We randomly assigned 782 infertile women without the polycystic ovary syndrome who were undergoing a first or second IVF cycle to receive either a frozen embryo or a fresh embryo on day 3. In the frozen-embryo group, all grade 1 and 2 embryos had been cryopreserved, and a maximum of two embryos were thawed on the day of transfer in the following cycle. In the fresh-embryo group, a maximum of two fresh embryos were transferred in the stimulated cycle. The primary outcome was ongoing pregnancy after the first embryo transfer. RESULTS: After the first completed cycle, ongoing pregnancy occurred in 142 of 391 women (36.3%) in the frozen-embryo group and in 135 of 391 (34.5%) in the fresh-embryo group (risk ratio in the frozen-embryo group, 1.05; 95% confidence interval [CI], 0.87 to 1.27; P=0.65). Rates of live birth after the first transfer were 33.8% and 31.5%, respectively (risk ratio, 1.07; 95% CI, 0.88 to 1.31). CONCLUSIONS: Among infertile women without the polycystic ovary syndrome who were undergoing IVF, the transfer of frozen embryos did not result in significantly higher rates of ongoing pregnancy or live birth than the transfer of fresh embryos. (Funded by My Duc Hospital; ClinicalTrials.gov number, NCT02471573 .).


Assuntos
Criopreservação , Transferência Embrionária , Fertilização in vitro , Infertilidade Feminina , Taxa de Gravidez , Adulto , Transferência Embrionária/métodos , Feminino , Humanos , Recém-Nascido , Análise de Intenção de Tratamento , Nascido Vivo , Indução da Ovulação , Síndrome do Ovário Policístico , Gravidez , Complicações na Gravidez
10.
Hum Reprod ; 36(7): 1821-1831, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33930124

RESUMO

STUDY QUESTION: Does the addition of oral dydrogesterone to vaginal progesterone as luteal phase support improve pregnancy outcomes during frozen embryo transfer (FET) cycles compared with vaginal progesterone alone? SUMMARY ANSWER: Luteal phase support with oral dydrogesterone added to vaginal progesterone had a higher live birth rate and lower miscarriage rate compared with vaginal progesterone alone. WHAT IS KNOWN ALREADY: Progesterone is an important hormone that triggers secretory transformation of the endometrium to allow implantation of the embryo. During IVF, exogenous progesterone is administered for luteal phase support. However, there is wide inter-individual variation in absorption of progesterone via the vaginal wall. Oral dydrogesterone is effective and well tolerated when used to provide luteal phase support after fresh embryo transfer. However, there are currently no data on the effectiveness of luteal phase support with the combination of dydrogesterone with vaginal micronized progesterone compared with vaginal micronized progesterone after FET. STUDY DESIGN, SIZE, DURATION: Prospective cohort study conducted at an academic infertility center in Vietnam from 26 June 2019 to 30 March 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: We studied 1364 women undergoing IVF with FET. Luteal support was started when endometrial thickness reached ≥8 mm. The luteal support regimen was either vaginal micronized progesterone 400 mg twice daily plus oral dydrogesterone 10 mg twice daily (second part of the study) or vaginal micronized progesterone 400 mg twice daily (first 4 months of the study). In women with a positive pregnancy test, the appropriate luteal phase support regimen was continued until 7 weeks' gestation. The primary endpoint was live birth after the first FET of the started cycle, with miscarriage <12 weeks as one of the secondary endpoints. MAIN RESULTS AND THE ROLE OF CHANCE: The vaginal progesterone + dydrogesterone group and vaginal progesterone groups included 732 and 632 participants, respectively. Live birth rates were 46.3% versus 41.3%, respectively (rate ratio [RR] 1.12, 95% CI 0.99-1.27, P = 0.06; multivariate analysis RR 1.30 (95% CI 1.01-1.68), P = 0.042), with a statistically significant lower rate of miscarriage at <12 weeks in the progesterone + dydrogesterone versus progesterone group (3.4% versus 6.6%; RR 0.51, 95% CI 0.32-0.83; P = 0.009). Birth weight of both singletons (2971.0 ± 628.4 versus 3118.8 ± 559.2 g; P = 0.004) and twins (2175.5 ± 494.8 versus 2494.2 ± 584.7; P = 0.002) was significantly lower in the progesterone plus dydrogesterone versus progesterone group. LIMITATIONS, REASONS FOR CAUTION: The main limitations of the study were the open-label design and the non-randomized nature of the sequential administration of study treatments. However, our systematic comparison of the two strategies was able to be performed much more rapidly than a conventional randomized controlled trial. In addition, the single ethnicity population limits external generalizability. WIDER IMPLICATIONS OF THE FINDINGS: Our findings study suggest a role for oral dydrogesterone in addition to vaginal progesterone as luteal phase support in FET cycles to reduce the miscarriage rate and improve the live birth rate. Carefully planned prospective cohort studies with limited bias could be used as an alternative to randomized controlled clinical trials to inform clinical practice. STUDY FUNDING/COMPETING INTERESTS: This study received no external funding. LNV has received speaker and conference fees from Merck, grant, speaker and conference fees from Merck Sharpe and Dohme, and speaker, conference and scientific board fees from Ferring; TMH has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; R.J.N. has received scientific board fees from Ferring and receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; BWM has acted as a paid consultant to Merck, ObsEva and Guerbet, and is the recipient of grant money from an NHMRC Investigator Grant. TRIAL REGISTRATION NUMBER: NCT0399876.


Assuntos
Didrogesterona , Progesterona , Austrália , Feminino , Fertilização in vitro , Humanos , Fase Luteal , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Vietnã
11.
J Assist Reprod Genet ; 38(6): 1293-1302, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33825118

RESUMO

PURPOSE: In vitro maturation (IVM) is an alternative to in vitro fertilization (IVF) for women at high risk of developing ovarian hyperstimulation syndrome (OHSS). This study determined the effectiveness and safety of a freeze-only strategy versus fresh embryo transfer (ET) after IVM with a pre-maturation step (CAPA-IVM) in women with a high antral follicle count (AFC). METHODS: This randomized, controlled pilot study (NCT04297553) was conducted between March and November 2020. Forty women aged 18-37 years with a high AFC (≥24 follicles in both ovaries) undergoing one cycle of CAPA-IVM were randomized to a freeze-only strategy with subsequent frozen ET (n = 20) or to fresh ET (n = 20). The primary endpoint was ongoing pregnancy resulting in live birth after the first ET of the started treatment cycle. RESULTS: The ongoing pregnancy rate in the freeze-only group (65%) was significantly higher than that in the fresh ET group (25%; p = 0.03), as was the live birth rate (60% versus 20%; p = 0.02). Clinical pregnancy rate was numerically, but not significantly, higher after frozen versus fresh ET (70% versus 35%; p = 0.06), while the number of day 3 or good quality embryos, endometrial thickness on the day of oocyte pick-up, implantation rate, and positive pregnancy test rate did not differ significantly between groups. No cases of OHSS were observed, and miscarriage and multiple pregnancy rates were similar in the two groups. CONCLUSIONS: These findings suggest that the effectiveness of CAPA-IVM could be improved considerably by using a freeze-only strategy followed by frozen ET in subsequent cycles. TRIAL REGISTRATION NUMBER: NCT04297553 ( www.clinicaltrials.gov ).


Assuntos
Congelamento/efeitos adversos , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/crescimento & desenvolvimento , Adolescente , Adulto , Coeficiente de Natalidade , Criopreservação/métodos , Transferência Embrionária , Feminino , Humanos , Nascido Vivo/epidemiologia , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Adulto Jovem
12.
Genes Dev ; 27(12): 1378-90, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23788624

RESUMO

Although it is known that OCT4-NANOG are required for maintenance of pluripotent cells in vitro, the upstream signals that regulate this circuit during early development in vivo have not been identified. Here we demonstrate, for the first time, signal transducers and activators of transcription 3 (STAT3)-dependent regulation of the OCT4-NANOG circuitry necessary to maintain the pluripotent inner cell mass (ICM), the source of in vitro-derived embryonic stem cells (ESCs). We show that STAT3 is highly expressed in mouse oocytes and becomes phosphorylated and translocates to the nucleus in the four-cell and later stage embryos. Using leukemia inhibitory factor (Lif)-null embryos, we found that STAT3 phosphorylation is dependent on LIF in four-cell stage embryos. In blastocysts, interleukin 6 (IL-6) acts in an autocrine fashion to ensure STAT3 phosphorylation, mediated by janus kinase 1 (JAK1), a LIF- and IL-6-dependent kinase. Using genetically engineered mouse strains to eliminate Stat3 in oocytes and embryos, we firmly establish that STAT3 is essential for maintenance of ICM lineages but not for ICM and trophectoderm formation. Indeed, STAT3 directly binds to the Oct4 and Nanog distal enhancers, modulating their expression to maintain pluripotency of mouse embryonic and induced pluripotent stem cells. These results provide a novel genetic model of cell fate determination operating through STAT3 in the preimplantation embryo and pluripotent stem cells in vivo.


Assuntos
Massa Celular Interna do Blastocisto , Linhagem da Célula , Células-Tronco Embrionárias/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio , Fator 3 de Transcrição de Octâmero , Fator de Transcrição STAT3 , Animais , Massa Celular Interna do Blastocisto/citologia , Massa Celular Interna do Blastocisto/metabolismo , Células Cultivadas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fosforilação , Células-Tronco Pluripotentes/fisiologia , Ligação Proteica , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
13.
Hum Reprod ; 35(11): 2537-2547, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32974672

RESUMO

STUDY QUESTION: Is one cycle of IVM non-inferior to one cycle of conventional in IVF with respect to live birth rates in women with high antral follicle counts (AFCs)? SUMMARY ANSWER: We could not demonstrate non-inferiority of IVM compared with IVF. WHAT IS KNOWN ALREADY: IVF with ovarian hyperstimulation has limitations in some subgroups of women at high risk of ovarian stimulation, such as those with polycystic ovary syndrome. IVM is an alternative ART for these women. IVM may be a feasible alternative to IVF in women with a high AFC, but there is a lack of data from randomized clinical trials comparing IVM with IVF in women at high risk of ovarian hyperstimulation syndrome. STUDY DESIGN, SIZE, DURATION: This single-center, randomized, controlled non-inferiority trial was conducted at an academic infertility center in Vietnam from January 2018 to April 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total, 546 women with an indication for ART and a high AFC (≥24 follicles in both ovaries) were randomized to the IVM (n = 273) group or the IVF (n = 273) group; each underwent one cycle of IVM with a prematuration step versus one cycle of IVF using a standard gonadotropin-releasing hormone antagonist protocol with gonadotropin-releasing hormone agonist triggering. The primary endpoint was live birth rate after the first embryo transfer. The non-inferiority margin for IVM versus IVF was -10%. MAIN RESULTS AND THE ROLE OF CHANCE: Live birth after the first embryo transfer occurred in 96 women (35.2%) in the IVM group and 118 women (43.2%) in the IVF group (absolute risk difference -8.1%; 95% confidence interval (CI) -16.6%, 0.5%). Cumulative ongoing pregnancy rates at 12 months after randomization were 44.0% in the IVM group and 62.6% in the IVF group (absolute risk difference -18.7%; 95% CI -27.3%, -10.1%). Ovarian hyperstimulation syndrome did not occur in the IVM group, versus two cases in the IVF group. There were no statistically significant differences between the IVM and IVF groups with respect to the occurrence of pregnancy complications, obstetric and perinatal complications, preterm delivery, birth weight and neonatal complications. LIMITATIONS, REASONS FOR CAUTION: The main limitation of the study was its open-label design. In addition, the findings are only applicable to IVM conducted using the prematuration step protocol used in this study. Finally, the single ethnicity population limits the external generalizability of the findings. WIDER IMPLICATIONS OF THE FINDINGS: Our randomized clinical trial compares live birth rates after IVM and IVF. Although IVM is a viable and safe alternative to IVF that may be suitable for some women seeking a mild ART approach, the current study findings approach inferiority for IVM compared with IVF when cumulative outcomes are considered. Future research should incorporate multiple cycles of IVM in the study design to estimate cumulative fertility outcomes and better inform clinical decision-making. STUDY FUNDING/COMPETING INTEREST(S): This work was partly supported by Ferring grant number 000323 and funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) and by the Fund for Research Flanders (FWO). LNV has received speaker and conference fees from Merck, grant, speaker and conference fees from Merck Sharpe and Dohme, and speaker, conference and scientific board fees from Ferring; TMH has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; RJN has received conference and scientific board fees from Ferring, is a minor shareholder in an IVF company, and receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; BWM has acted as a paid consultant to Merck, ObsEva and Guerbet, and is the recipient of grant money from an NHMRC Investigator Grant; RBG reports grants and fellowships from the NHMRC of Australia; JS reports lecture fees from Ferring Pharmaceuticals, Biomérieux, Besins Female Healthcare and Merck, grants from Fund for Research Flanders (FWO), and is co-inventor on granted patents on CAPA-IVM methodology in the US (US10392601B2) and Europe (EP3234112B1); TDP, VQD, VNAH, NHG, AHL, THP and RW have no financial relationships with any organizations that might have an interest in the submitted work in the previous three years, and no other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: NCT03405701 (www.clinicaltrials.gov). TRIAL REGISTRATION DATE: 16 January 2018. DATE OF FIRST PATENT'S ENROLMENT: 25 January 2018.


Assuntos
Infertilidade , Austrália , Europa (Continente) , Feminino , Fertilização in vitro , Humanos , Recém-Nascido , Oócitos , Gravidez , Vietnã
14.
Clin Lab ; 66(12)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33337827

RESUMO

BACKGROUND: Although TSH suppression by elevated ß-hCG is essentially seen during first trimester, differences in TSH reference ranges between various countries have been reported. Physiologic changes during pregnancy may also influence FT4 assays. This study aims to establish method-specific reference intervals (RIs) of TSH, FT4, and FT3 in Vietnamese, first trimester pregnant women. METHODS: This cross-sectional study was conducted at My Duc Hospital, Ho Chi Minh, Vietnam. Women with singleton pregnancies in the first trimester and conceived naturally were included. Those with a history of thyroid disease, positive thyroid-specific autoantibodies, diffuse goiter or one thyroid nodule > 10 mm in size or ≥ 2 nodules detected by ultrasound, and taking medications affecting thyroid function were excluded. Serum TSH, FT4, and FT3 were measured by chemiluminescent detection technology on the Access 2 Immunoassay System (Beckman Coulter, Inc., USA). Intra- and interassay coefficients of variations (CV) were 3.6% and 4.4% for TSH, 5.4% and 6.1% for FT4, 6.6%, and 6.0% for FT3, respectively. The 2.5th and 97.5th percentiles were used to determine RIs. RESULTS: Between August 1, 2017, to December 1, 2018, there were 876 pregnant women who fulfilled inclusion and exclusion criteria. They had a mean age of 30.1 years, an average BMI of 21.3 kg/m2, and 77.3% of them were primigravida. The RIs for TSH, FT4 and FT3 were 0.17 - 2.35 mIU/L, 0.67 - 1.11 ng/dL and 2.82 - 3.90 pg/mL, respectively. CONCLUSIONS: Established RIs for TSH, FT4, and FT3 in Vietnamese women would help to reduce the misdiagnosis of gestational thyroid disorders.


Assuntos
Testes de Função Tireóidea , Tiroxina , Adulto , Povo Asiático , Estudos Transversais , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Gestantes , Valores de Referência , Tireotropina , Tri-Iodotironina
15.
Reprod Biomed Online ; 38(3): 387-396, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30711459

RESUMO

RESEARCH QUESTION: What are the roles of serum progesterone and endometrial thickness as biomarkers in the decision between a freeze-only and fresh embryo transfer in IVF for women without polycystic ovary syndrome (PCOS)? DESIGN: This was a secondary analysis of a randomized controlled trial including 782 couples who were followed up until the end of the first completed cycle. Couples scheduled for their first or second IVF cycle with a FSH/gonadotrophin-releasing hormone antagonist protocol were randomized to a freeze-only (n = 391) or fresh embryo transfer (n = 391) strategy. The endpoint for this analysis was live birth rate (LBR) after the first embryo transfer. RESULTS: There was no significant difference in LBR after the first cycle between a freeze-only and fresh transfer strategy. When serum progesterone levels at trigger were in the third quartile (Q3, 1.14-1.53 ng/ml), LBR was significantly higher in the freeze-only versus fresh transfer group (P = 0.01); when serum progesterone was ≥1.14 ng/ml, LBR was significantly better in the freeze-only group (37.4% versus 23.8% in the fresh transfer group; P = 0.004). LBRs in the freeze-only and fresh embryo transfer groups were similar across all quartiles of endometrial thickness, although a small advantage for freeze-only in women with a very thin endometrium could not be excluded. CONCLUSIONS: Serum progesterone level on the day of trigger may have potential as a biomarker on which to base a prospective decision about whether to use a freeze-only or fresh embryo transfer strategy in women undergoing IVF.


Assuntos
Coeficiente de Natalidade , Transferência Embrionária/métodos , Endométrio/diagnóstico por imagem , Nascido Vivo , Progesterona/sangue , Adulto , Feminino , Fertilização in vitro , Antagonistas de Hormônios/uso terapêutico , Humanos , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Ultrassonografia Pré-Natal
16.
Hum Reprod ; 33(10): 1907-1914, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239784

RESUMO

STUDY QUESTION: Is a freeze-only strategy more cost-effective from a patient perspective than fresh embryo transfer (ET) after one completed In Vitro Fertilization/ Intracytoplasmic Sperm Injection (IVF/ICSI) cycle in women without polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: There is a low probability of the freeze-only strategy being cost-effective over the fresh ET strategy for non-PCOS women undergoing IVF/ICSI. WHAT IS KNOWN ALREADY: Conventionally, IVF embryos are transferred in the same cycle in which oocytes are collected, while any remaining embryos are frozen and stored. We recently evaluated the effectiveness of a freeze-only strategy compared with a fresh ET strategy in a randomized controlled trial (RCT). There was no difference in live birth rate between the two strategies. STUDY DESIGN, SIZE, DURATION: A cost-effectiveness analysis (CEA) was performed alongside the RCT to compare a freeze-only strategy with a fresh ET strategy in non-PCOS women undergoing IVF/ICSI. The effectiveness measure for the CEA was the live birth rate. Data on the IVF procedure, pregnancy outcomes and complications were collected from chart review; additional information was obtained using patient questionnaires, by telephone. PARTICIPANTS/MATERIALS, SETTING, METHODS: For all patients, we measured the direct medical costs relating to treatment (cryopreservation, pregnancy follow-up, delivery), direct non-medical costs (travel, accommodation) and indirect costs (income lost). The direct cost data were calculated from resources obtained from patient records and prices were applied based on a micro-costing approach. Indirect costs were calculated based on responses to the questionnaire. Patients were followed until all embryos obtained from a single controlled ovarian hyperstimulation cycle were used or a live birth was achieved. The incremental cost-effectiveness ratio (ICER) was based on the incremental cost per couple and the incremental live birth rate of the freeze-only strategy compared with the fresh ET strategy. Probabilistic sensitivity analysis (PSA) and a cost-effectiveness acceptability curve (CEAC) were also performed. MAIN RESULTS AND THE ROLE OF CHANCE: Between June 2015 and April 2016, 782 couples were randomized to a freeze-only (n = 391) or a fresh ET strategy (n = 391). Baseline characteristics including mean age, Body Mass Index (BMI), anti-Mullerian hormone, total dose of Follicle Stimulating Hormone (FSH), number of oocytes obtained, good quality Day 3 embryos, fertility outcomes and treatment complications were comparable between the two groups. The live birth rate (48.6% vs. 47.3%, respectively; risk ratio, 1.03; 95% Confidence Interval [CI], 0.89, 1.19; P = 0.78) and the average cost per couple (3906 vs. 3512 EUR, respectively; absolute difference 393.6, 95% CI, -76.2, 863.5; P = 0.1) were similar in the freeze-only group versus fresh ET. Corresponding costs per live birth were 8037 EUR versus 7425 EUR in the freeze-only versus fresh ET group, respectively. The incremental cost for the freeze-only strategy compared with fresh ET was 30 997 EUR per 1% additional live birth rate. The direct non-medical costs and indirect costs of infertility treatment strategies represented ~45-52% of the total cost. PSA shows that the 95% CI of ICERs was -263 901 to 286 681 EUR. Out of 1000 simulations, 44% resulted in negative ICERs, including 13.0% of simulations in which the freeze-only strategy was dominant (more effective and less costly than fresh ET), and 31% of simulations in which the fresh embryo strategy was dominant. In the other 560 simulations with positive ICERs, the 95% CI of ICERs ranged from 2155 to 471 578 EUR. The CEAC shows that at a willingness to pay threshold of 300 000 EUR, the probability of the freeze-only strategy being cost-effective over the fresh ET strategy would be 58%. LIMITATIONS, REASONS FOR CAUTION: Data were collected from a single private IVF center study in Vietnam where there is no public or insurance funding of IVF. Unit costs obtained might not be representative of other settings. Data obtained from secondary sources (medical records, financial and activity reports) could lack authenticity, and recall bias may have influenced questionnaire responses on which direct costs were based. WIDER IMPLICATIONS OF THE FINDINGS: In non-PCOS women undergoing IVF/ICSI, the results suggested that the freeze-only strategy was not cost-effective compared with fresh ET from a patient perspective. These findings indicate that other factors could be more important in deciding whether to use a freeze-only versus fresh ET strategy in this patient group. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by My Duc Hospital; no external funding was received. Ben Willem J. Mol is supported by an NHMRC Practioner Fellowship (GNT 1082548) and reports consultancy for Merck, ObsEva and Guerbet. Robert J. Norman has shares in an IVF company and has received support from Merck and Ferring. All other authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Criopreservação/economia , Transferência Embrionária/métodos , Fertilização in vitro/economia , Coeficiente de Natalidade , Análise Custo-Benefício , Transferência Embrionária/economia , Feminino , Humanos , Síndrome do Ovário Policístico , Gravidez , Inquéritos e Questionários , Vietnã
17.
Nanotechnology ; 28(4): 045401, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-27981942

RESUMO

In this research, an InGaN-based photoanode with a broadband light-absorption range from ultraviolet to green, patterned by imprint lithography and branched by ZnO nanowires, has been applied to water splitting. Over the solar spectrum range, the absorbance increases due to the scattering effect of the micro-structure compared to that of flat surface InGaN, which reaches a maximum of over 90% at 380 nm as ZnO nanowires are further employed in this novel photoanode. Consequently, the induced photocurrent density of the InGaN photoanode with a domelike structure and ZnO nanowires on the surface shows a remarkable enhancement of seven times that of the one with a flat surface. Further investigation indicates the wet-etching process for defect removal has an essential impact on photocurrent efficiency. This design demonstrates an innovative approach for water splitting.

18.
J Virol ; 89(16): 8114-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26063420

RESUMO

Molluscs, comprising one of the most successful phyla, lack clear evidence of adaptive immunity and yet thrive in the oceans, which are rich in viruses. There are thought to be nearly 120,000 species of Mollusca, most living in marine habitats. Despite the extraordinary abundance of viruses in oceans, molluscs often have very long life spans (10 to 100 years). Thus, their innate immunity must be highly effective at countering viral infections. Antiviral compounds are a crucial component of molluscan defenses against viruses and have diverse mechanisms of action against a wide variety of viruses, including many that are human pathogens. Antiviral compounds found in abalone, oyster, mussels, and other cultured molluscs are available in large supply, providing good opportunities for future research and development. However, most members of the phylum Mollusca have not been examined for the presence of antiviral compounds. The enormous diversity and adaptations of molluscs imply a potential source of novel antiviral compounds for future drug discovery.


Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Biologia Marinha , Moluscos , Animais
20.
Exp Lung Res ; 42(3): 121-30, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27093376

RESUMO

UNLABELLED: Purpose/Aim of Study: The renin angiotensin system is involved in experimentally induced lung fibrosis. Angiotensin (ANG)-II is profibrotic. Angiotensin converting enzyme-2 (ACE-2) cleaves ANG-II and is thus protective. ACE-2 has recently been reported to be significantly decreased under hyperoxic conditions. Hyperoxia is linked to Bronchopulmonary Dysplasia and lung fibrosis. Fetal lung cells normally do not undergo fibrotic changes with physiologic hypoxemia. We hypothesized that hypoxia prior to hyperoxic exposure in fetal lung fibroblasts (IMR-90 cell line) might be protective by preventing ACE-2 downregulation. MATERIALS AND METHODS: IMR-90 cells were exposed to hypoxia (1%O2/99%N2) followed by hyperoxia (95%O2/5%CO2) or normoxia (21%O2) in vitro. Cells and culture media were recovered separately for assays of ACE-2, TNF-α-converting enzyme (TACE), αSmooth muscle actin (αSMA)-myofibroblast marker-, N-cadherin, and ß-catenin immunoreactive protein. RESULTS: ACE-2 significantly increased when IMR-90 were hypoxic prior to hyperoxic exposure with no recovery. In contrast to hyperoxia alone, ACE-2 did not decrease when IMR-90 were hypoxic prior to hyperoxic exposure with recovery. TACE/ADAM17 protein and mRNA were significantly decreased under these conditions. αSMA N-cadherin, and ß-catenin proteins were significantly decreased with or without normoxic recovery. CONCLUSIONS: Hypoxia prior to hyperoxic exposure of fetal lung fibroblasts prevented ACE-2 downregulation and decreased ADAM17/TACE protein and mRNA. αSMA, N-cadherin, and ß-catenin were also significantly decreased under these conditions.


Assuntos
Regulação para Baixo/fisiologia , Fibroblastos/fisiologia , Hiperóxia/fisiopatologia , Hipóxia/fisiopatologia , Pulmão/fisiologia , Peptidil Dipeptidase A/metabolismo , Actinas/metabolismo , Angiotensina II/metabolismo , Enzima de Conversão de Angiotensina 2 , Caderinas/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Hiperóxia/metabolismo , Hipóxia/metabolismo , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo , beta Catenina/metabolismo
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