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BACKGROUND: Use of frozen embryo transfer (FET) in in-vitro fertilisation (IVF) has increased. However, the best endometrial preparation protocol for FET cycles is unclear. We compared natural and modified natural cycle strategies with an artificial cycle strategy for endometrial preparation before FET. METHODS: In this randomised, open-label study, we recruited ovulatory women aged 18-45 years at a hospital in Ho Chi Minh City, Viet Nam, who were randomly allocated (1:1:1) to natural, modified natural, or artificial cycle endometrial preparation using a computer-generated random list and block randomisation. The trial was not masked due to the nature of the study interventions. In natural cycles, no oestrogen, progesterone, or human chorionic gonadotropin (hCG) was used. In modified natural cycles, hCG was used to trigger ovulation. In artificial cycles, oral oestradiol valerate (8 mg/day from day 2-4 of menstruation) and vaginal progesterone (800 mg/day starting when endometrial thickness was ≥7 mm) were used. Embryos were vitrified, and then one or two day-3 embryos or one day-5 embryo were warmed and transferred under ultrasound guidance. If the first FET cycle was cancelled, subsequent cycles were performed with artificial endometrial preparation. The primary endpoint was livebirth after one FET. This trial is registered at ClinicalTrials.gov, NCT04804020. FINDINGS: Between March 22, 2021, and March 14, 2023, 4779 women were screened and 1428 were randomly assigned (476 to each group). 99 first FET cycles were cancelled in each of the natural and modified cycle groups, versus none in the artificial cycle group. The livebirth rate after one FET was 174 (37%) of 476 in the natural cycle strategy group, 159 (33%) of 476 in the modified natural cycle strategy group, and 162 (34%) of 476 in the artificial cycle strategy group (relative risk 1·07 [95% CI 0·87-1·33] for natural vs artificial cycle strategy, and 0·98 [0·79-1·22] for modified natural vs artificial cycle strategy). Maternal and neonatal outcomes did not differ significantly between groups, as the power to detect small differences was low. INTERPRETATION: Although the livebirth rate was similar after natural, modified natural, and artificial cycle endometrial preparation strategies in ovulatory women undergoing FET IVF, no definitive conclusions can be made regarding the comparative safety of the three approaches. FUNDING: None.
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Criopreservación , Transferencia de Embrión , Endometrio , Nacimiento Vivo , Progesterona , Humanos , Femenino , Adulto , Transferencia de Embrión/métodos , Embarazo , Vietnam , Progesterona/administración & dosificación , Adulto Joven , Estradiol/administración & dosificación , Ovulación/efectos de los fármacos , Adolescente , Fertilización In Vitro/métodos , Inducción de la Ovulación/métodos , Persona de Mediana Edad , Índice de Embarazo , Gonadotropina Coriónica/administración & dosificaciónRESUMEN
STUDY QUESTION: In non-male factor infertile couples, are there any differences in the developmental outcomes between children born through ICSI and conventional IVF (cIVF)? SUMMARY ANSWER: In this preliminary study, ICSI and cIVF seem to have a comparable effect on developmental outcomes after 12 months in children born to non-male factor infertile couples. WHAT IS KNOWN ALREADY: ICSI, an invasive technique, has raised concerns about potential developmental abnormalities in children. Limited data are available regarding the developmental outcomes of ICSI-conceived infants born to non-male factor infertile couples. STUDY DESIGN, SIZE, DURATION: This prospective cohort study involved a follow-up of all children aged 12 months or older who were born from pregnancies resulting from either ICSI or cIVF as part of a previous randomized controlled trial (RCT) (NCT03428919). PARTICIPANTS/MATERIALS, SETTING, METHODS: In the original RCT, 1064 women were randomly assigned to the ICSI or cIVF groups (532 women for each group). Follow-up was conducted with 155 couples (195 children) in the ICSI group and 141 couples (185 children) in the cIVF group. The Vietnamese version of the Ages & Stages Third Edition Questionnaires (ASQ-3) and the Development Red Flags questionnaires were completed by the participants. A total of 141 (90.1%) women (177 children) in the ICSI group and 113 (80.1%) women (145 children) in the cIVF group returned fully completed questionnaires. The primary outcomes were the developmental outcomes based on responses to the ASQ-3 and the Red Flags questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: The mean age of children at follow-up was 19.5 ± 5.0 months in the ICSI group and 19.3 ± 5.5 months in the cIVF group. The mean height and weight of children in both groups were similar. The overall proportion of children with any abnormal ASQ-3 score did not differ significantly between the ICSI and cIVF groups (16.9% vs 13.1%, P = 0.34). The proportion of children with Red Flag signs was also comparable between the two groups (6.2% vs 9.2%, P = 0.36, ICSI vs cIVF, respectively). LIMITATIONS, REASONS FOR CAUTION: Despite a reasonably high follow-up response rate, there is a potential risk of sampling bias, and overall, the number of children with developmental abnormalities was very small. The study relied solely on questionnaires as screening tools, rather than incorporating additional behavioral observations or physical developmental tests; this may have affected the statistical power and the significance of between-group comparisons. WIDER IMPLICATIONS OF THE FINDINGS: The current findings contribute to the existing evidence and support the comparative safety of ICSI and cIVF regarding early childhood development. However, more extensive and prolonged follow-up data for these children are needed to draw definitive conclusions. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study, and no authors reported conflicting interests. TRIAL REGISTRATION NUMBER: NCT04866524 (clinicaltrials.gov).
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Escherichia coli expresses surface appendages including fimbriae, flagella, and curli, at various levels in response to environmental conditions and external stimuli. Previous studies have revealed an interplay between expression of fimbriae and flagella in several E. coli strains, but how this regulation between fimbrial and flagellar expression affects adhesion to interfaces is incompletely understood. Here, we investigate how the concurrent expression of fimbriae and flagella by engineered strains of E. coli MG1655 affects their adhesion at liquid-solid and liquid-liquid interfaces. We tune fimbrial and flagellar expression on the cell surface through plasmid-based inducible expression of the fim operon and fliC-flhDC genes. We show that increased fimbrial expression increases interfacial adhesion as well as bacteria-driven actuation of micron-sized objects. Co-expression of flagella in fimbriated bacteria, however, does not greatly affect either of these properties. Together, these results suggest that interfacial adhesion as well as motion actuated by adherent bacteria can be altered by controlling the expression of surface appendages.
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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.
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Muerte Perinatal , Nacimiento Prematuro , Embarazo , Recién Nacido , Femenino , Niño , Humanos , Progesterona , Embarazo Gemelar , Estudios de Seguimiento , Nacimiento Prematuro/prevención & control , Pesarios , Cuello del Útero , Administración IntravaginalRESUMEN
STUDY QUESTION: Is there any difference in developmental outcomes in children born after capacitation IVM (CAPA IVM) compared with conventional IVF? SUMMARY ANSWER: Overall development up to 24 months of age was comparable in children born after CAPA IVM compared with IVF. WHAT IS KNOWN ALREADY: IVM has been shown to be a feasible alternative to conventional IVF in women with a high antral follicle count (AFC). In addition to live birth rate, childhood development is also a relevant metric to compare between the two approaches to ART and there are currently no data on this. STUDY DESIGN, SIZE, DURATION: This study was a follow-up of babies born to women who participated in a randomized controlled trial comparing IVM with a pre-maturation step (CAPA IVM) and IVF. Developmental assessments were performed on 231 children over 24 months of follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants in the randomized controlled trial had an indication for ART and a high AFC (≥24 follicles in both ovaries). They were randomized to undergo one cycle of either IVM (n = 273) or IVF (n = 273). Of these, 96 women and 118 women, respectively, had live births. Seventy-six women (94 children, 79.2%) and 104 women (137 children, 88.1%), respectively, completed Ages & Stages Third Edition Questionnaire assessment (ASQ-3), and underwent evaluation of Developmental Red Flags at 6, 12 and 24 months of age. MAIN RESULTS AND THE ROLE OF CHANCE: Baseline characteristics of participants in the follow-up study between the IVM and IVF groups were comparable. Overall, there were no significant differences in ASQ-3 scores at 6, 12 and 24 months between children born after IVM or IVF. The proportion of children with developmental red flags was low and did not differ between the two groups. Slightly, but significantly, lower ASQ-3 problem solving and personal-social scores in twins from the IVM versus IVF group at 6 months were still within the normal range and had caught up to the IVF group in the 12- and 24-month assessments. The number of children confirmed to have abnormal mental and/or motor development after specialist assessment was four in the IVM group and two in the IVF group (relative risk 2.91, 95% CI 0.54-15.6; P = 0.23). LIMITATIONS, REASONS FOR CAUTION: This study is an open-label follow-up of participants in a randomized controlled trial, and not all original trial subjects took part in the follow-up. The self-selected nature of the follow-up population could have introduced bias, and the sample size may have been insufficient to detect significant between-group differences in developmental outcomes. WIDER IMPLICATIONS OF THE FINDINGS: Based on the current findings at 2 years of follow-up, there does not appear to be any significant concern about the effects of IVM on childhood development. These data add to the evidence available to physicians when considering different approaches to fertility treatment, but require validation in larger studies. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number FWO.106-YS.2017.02. L.N.V. 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; T.M.H. has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; R.J.N. has receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; B.W.M. has acted as a paid consultant to Merck, ObsEva and Guerbet and is the recipient of grant money from an NHMRC Investigator Grant; J.E.J.S. reports lecture fees from Ferring Pharmaceuticals, Biomérieux and Besins Female Healthcare, grants from Fund for Research Flanders (FWO) and is co-inventor on granted patents on CAPA-IVM methodology in the USA (US10392601B2) and Europe (EP3234112B1); T.D.P., M.H.N.N., N.A.N., T.T.L., V.T.T.T., N.T.N., H.L.T.H. and X.T.H.L. have no financial relationships with any organizations that might have an interest in the submitted work in the previous 3 years, and no other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: NCT04296357 (www.clinicaltrials.gov). TRIAL REGISTRATION DATE: 5 March 2020. DATE OF FIRST PATIENT'S ENROLMENT: 7 March 2020.
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Tasa de Natalidad , Inducción de la Ovulación , Niño , Femenino , Fertilización In Vitro/métodos , Estudios de Seguimiento , Humanos , Nacimiento Vivo , Inducción de la Ovulación/métodos , EmbarazoRESUMEN
Highly stretchable electrically conductive hydrogels have been extensively researched in recent years, especially for applications in strain and pressure sensing, electronic skin, and implantable bioelectronic devices. Herein, we present a new cross-linked complex coacervate approach to prepare conductive hydrogels that are both highly stretchable and compressive. The gels involve a complex coacervate between carboxylated nanogels and branched poly(ethylene imine), whereby the latter is covalently cross-linked by poly(ethylene glycol) diglycidyl ether (PEGDGE). Inclusion of graphene nanoplatelets (Gnp) provides electrical conductivity as well as tensile and compressive strain-sensing capability to the hydrogels. We demonstrate that judicious selection of the molecular weight of the PEGDGE cross-linker enables the mechanical properties of these hydrogels to be tuned. Indeed, the gels prepared with a PEGDGE molecular weight of 6000 g/mol defy the general rule that toughness decreases as strength increases. The conductive hydrogels achieve a compressive strength of 25 MPa and a stretchability of up to 1500%. These new gels are both adhesive and conformal. They provide a self-healable electronic circuit, respond rapidly to human motion, and can act as strain-dependent sensors while exhibiting low cytotoxicity. Our new approach to conductive gel preparation is efficient, involves only preformed components, and is scalable.
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Grafito , Dispositivos Electrónicos Vestibles , Adhesivos , Conductividad Eléctrica , Humanos , HidrogelesRESUMEN
The ability to remotely and non-invasively monitor and measure the strain within injectable gels used to augment soft tissue is highly desirable. Such information could enable real-time monitoring of gel performance and bespoke gel design. We report progress towards this goal using two fluorescent particle probe systems included within two different injectable gels. The two injectable gels have been previously studied in the contexts of intervertebral disc repair and stretchable gels for cartilage repair. The two fluorophore particle probes are blue or near-infrared (NIR) emitting and are present at very low concentrations. The normalised photoluminescence (PL) intensity from the blue emitting probe is shown to equal the compressive deformation ratio of the gels. Furthermore, the normalised ratio of the PL intensities for the blue and NIR probes varies linearly with deformation ratio over a wide range (from 0.2 to 3.0) with a seamless transition from compression to tension. Hence, PL can discriminate between compression and tension. The new approach established here should apply to other gels and enable remote detection of whether a gel is being compressed or stretched as well as the extent. This study may provide an important step towards remotely and minimally invasively measuring the strain experienced by load-supporting gels in vivo.
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Nanopartículas , Geles , PresiónRESUMEN
Nanogels are crosslinked polymer particles with a swollen size between 1 and 100 nm. They are of major interest for advanced surface coatings, drug delivery, diagnostics and biomaterials. Synthesising polyacid nanogels that show triggered swelling using a scalable approach is a key objective of polymer colloid chemistry. Inspired by the ability of polar surfaces to enhance nanoparticle stabilisation, we report the first examples of pH-responsive polyacid nanogels containing high -COOH contents prepared by a simple, scalable, aqueous method. To demonstrate their functionalisation potential, glycidyl methacrylate was reacted with the -COOH chemical handles and the nanogels were converted to macro-crosslinkers. The concentrated (functionalised) nanogel dispersions retained their pH-responsiveness, were shear-thinning and formed physical gels at pH 7.4. The nanogels were covalently interlinked via free-radical coupling at 37 °C to form transparent, ductile, hydrogels. Mixing of the functionalised nanogels with polymer dots enabled covalent assembly of fluorescent hydrogels.
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Gold nanoparticles (GNPs) have UV-visible absorption spectra that are highly sensitive to their local environment due to their surface plasmon resonance (SPR). Furthermore, GNPs are able to quench the fluorescence of suitable dyes depending on the GNP-dye separation. Both of these features have led to the use of GNPs as spectroscopic rulers. In this study we sought to use GNPs as spectroscopic probes to investigate the local structural changes associated with the macroscopic pH-triggered swelling/de-swelling transitions of a pH-responsive hydrogel. The hydrogel used in this study comprised covalently inter-linked pH-responsive poly(ethylacrylate-co-methacrylic acid-co-divinyl benzene) microgel particles (MGs). MGs are crosslinked polymer colloids that swell when the pH approaches the pKa of the constituent polymer. The interlinked MG hydrogels are termed doubly crosslinked microgels (DX MGs) and are a new family of hydrogels. They had polymer volume fractions (Ïp) that strongly decreased as the pH increased. UV-visible spectra showed that the wavelength of the SPR absorption (λmax) for the DX MG/GNP gels was pH-responsive. A linear relationship was found between λmax and Ïp for Ïp values up to â¼0.80. The inclusion of Rhodamine 6G within the DX MG/GNP hydrogels resulted in metal-induced fluorescence quenching which was studied using photoluminescence (PL) spectroscopy. The extent of quenching was pH-dependent and was also proportional to Ïp. The results of the study showed that the pH-triggered changes of the nanoscale and macroscopic swelling for the DX MGs were similar and imply that affine swelling occurred, which is a new observation. The data suggest that UV-visible or PL spectroscopy could be used to study the swelling of pH-responsive hydrogels containing GNPs remotely.
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Due to its high electron mobility, good stability and potential for low-temperature synthesis ZnO has received considerable attention for use in solar cells, photodetectors and sensors. Whilst there have been reports involving the formation ZnO films with porous morphologies the majority of those have involved elaborate or time-consuming preparation methods. In this study we investigate a simple new method for preparing textured porous ZnO (tp-ZnO) films. We used colloidal instability triggered by the evaporation of a volatile stabilising ligand during spin-coating of a ZnO nanocrystal (NC) dispersion to deposit crack-free tp-ZnO films. The porosity of the tp-ZnO films was 56% and they could be prepared using amine-based ligands with boiling points less than or equal to 78 °C. To demonstrate the ability to use the tp-ZnO films as electron acceptors they were infiltrated with poly(3-hexylthiophene) (P3HT) and solar cells prepared. The power conversion efficiencies of the tp-ZnO/P3HT devices reached values that were three times higher than a control bilayer ZnO/P3HT device prepared using a sol-gel derived ZnO film. Because our method used a low temperature treatment and ZnO films are used in a wide variety of third-generation solar cells, the new tp-ZnO films introduced here may offer a low cost method for improving the efficiency of other solar cells.
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Aryl hydrocarbon receptor (Ahr), a transcription factor, plays a critical role in autoimmune inflammation of the intestine. In addition, microRNAs (miRNAs), small non-coding oligonucleotides, mediate pathogenesis of inflammatory bowel diseases (IBD). However, the precise mechanism and interactions of these molecules in IBD pathogenesis have not yet been investigated. We analyzed the role of Ahr and Ahr-regulated miRNAs in colonic inflammation. Our results show that deficiency of Ahr in intestinal epithelial cells in mice exacerbated inflammation in dextran sodium sulfate-induced colitis. Deletion of Ahr in T cells attenuated colitis, which was manifested by suppressed Th17 cell infiltration into the lamina propria. Candidate miRNA analysis showed that induction of colitis elevated expression of the miR-212/132 cluster in the colon of wild-type mice, whereas in Ahr (-/-) mice, expression was clearly lower. Furthermore, miR-212/132(-/-) mice were highly resistant to colitis and had reduced levels of Th17 cells and elevated levels of IL-10-producing CD4(+) cells. In vitro analyses revealed that induction of type 1 regulatory T (Tr1) cells was significantly elevated in miR-212/132(-/-) T cells with increased c-Maf expression. Our findings emphasize the vital role of Ahr in intestinal homeostasis and suggest that inhibition of miR-212/132 represents a viable therapeutic strategy for treating colitis.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Colitis/genética , Interleucina-10/genética , MicroARNs/genética , Receptores de Hidrocarburo de Aril/genética , Animales , Secuencia de Bases , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/deficiencia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Proliferación Celular , Colitis/inducido químicamente , Colitis/inmunología , Colitis/patología , Sulfato de Dextran , Femenino , Regulación de la Expresión Génica , Homeostasis/inmunología , Interleucina-10/inmunología , Intestinos/inmunología , Intestinos/patología , Recuento de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/inmunología , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-maf/genética , Proteínas Proto-Oncogénicas c-maf/inmunología , Receptores de Hidrocarburo de Aril/deficiencia , Receptores de Hidrocarburo de Aril/inmunología , Transducción de Señal , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología , Células Th17/inmunología , Células Th17/patologíaRESUMEN
Developing medical devices that resist bacterial attachment and subsequent biofilm formation is highly desirable. In this paper, we report the optimization of the molecular structure and thus material properties of a range of (meth)acrylate copolymers which contain monomers reported to deliver bacterial resistance to surfaces. This optimization allows such monomers to be employed within novel coatings to reduce bacterial attachment to silicone urinary catheters. We show that the flexibility of copolymers can be tuned to match that of the silicone catheter substrate, by copolymerizing these polymers with a lower Tg monomer such that it passes the flexing fatigue tests as coatings upon catheters, that the homopolymers failed. Furthermore, the Tg values of the copolymers are shown to be readily estimated by the Fox equation. The bacterial resistance performance of these copolymers were typically found to be better than the neat silicone or a commercial silver containing hydrogel surface, when the monomer feed contained only 25 v% of the "hit" monomer. The method of initiation (either photo or thermal) was shown not to affect the bacterial resistance of the copolymers. Optimized synthesis conditions to ensure that the correct copolymer composition and to prevent the onset of gelation are detailed.
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Acrilatos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana , Polímeros/farmacología , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Sustancias Macromoleculares/química , Polimerizacion , Polímeros/químicaRESUMEN
The use of dielectric property measurements to define specific trends in the molecular structures of poly(caprolactone) containing star polymers and/or the interbatch repeatability of the synthetic procedures used to generate them is demonstrated. The magnitude of the dielectric property value is shown to accurately reflect: (a) the number of functional groups within a series of materials with similar molecular size when no additional intermolecular order is present in the medium, (b) the polymer molecular size for a series of materials containing a fixed core material and so functional group number, and/or (c) the batch to batch repeatability of the synthesis method. The dielectric measurements are validated by comparison to spectroscopic/chromatographic data.
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Materiales Biocompatibles/síntesis química , Poliésteres/síntesis química , Tensoactivos/síntesis química , Espectroscopía Dieléctrica , Estructura Molecular , TemperaturaRESUMEN
Macromolecules that possess three-dimensional, branched molecular structures are of great interest because they exhibit significantly differentiated application performance compared to conventional linear (straight chain) polymers. This paper reports the synthesis of 3- and 4-arm star branched polymers via ring opening polymerisation (ROP) utilising multi-functional hydroxyl initiators and Sn(Oct)2 as precatalyst. The structures produced include mono-functional hydrophobic and multi-functional amphiphilic core corona stars. The characteristics of the synthetic process were shown to be principally dependent upon the physical/dielectric properties of the initiators used. ROP's using initiators that were more available to become directly involved with the Sn(Oct)2 in the "in-situ" formation of the true catalytic species were observed to require shorter reaction times. Use of microwave heating (MWH) in homopolymer star synthesis reduced reaction times compared to conventional heating (CH) equivalents, this was attributed to an increased rate of "in-situ" catalyst formation. However, in amphiphilic core corona star formation, the MWH polymerisations exhibited slower propagation rates than CH equivalents. This was attributed to macro-structuring within the reaction medium, which reduced the potential for reaction. It was concluded that CH experiments were less affected by this macro-structuring because it was disrupted by the thermal currents/gradients caused by the conductive/convective heating mechanisms. These gradients are much reduced/absent with MWH because it selectively heats specific species simultaneously throughout the entire volume of the reaction medium. These partitioning problems were overcome by introducing additional quantities of the species that had been determined to selectively heat.
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Poliésteres/química , Polímeros/química , Técnicas de Química Sintética , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Polimerizacion , Polímeros/síntesis química , TemperaturaRESUMEN
BACKGROUND: Despite the importance of early initiation of and exclusive breastfeeding, prelacteal feeds continue to pose a barrier to optimal breastfeeding practices in several countries, including Vietnam. This study examined the factors associated with prelacteal feeding among Vietnamese mothers. METHODS: Data from 6068 mother-child (<6 m) dyads were obtained from a cross-sectional survey conducted in 11 provinces in Vietnam in 2011. Multivariate logistic regression analyses were used to examine factors associated with prelacteal feeding. RESULTS: During the first three days after birth, 73.3% of the newborns were fed prelacteals, 53.5% were fed infants formula, and 44.1% were fed water. The odds of feeding prelacteals declined with increased breastfeeding knowledge, beliefs about social norms in favor of exclusive breastfeeding, and confidence in one's own breastfeeding behaviors. Women who harbored misconceptions about breastfeeding had twice the odds of feeding any prelacteals (OR: 2.09, 95% CI: 1.74-2.50). Health care factors increasing the odds of prelacteal feeding included delivery by caesarean section (OR: 2.94, 95% CI: 2.39-3.61) or episiotomy (OR: 1.36, 95% CI: 1.17-1.58) and experiencing breastfeeding problems (OR: 1.31, 95% CI: 1.04-1.66). Health staff support during pregnancy and after birth reduced the odds of feeding formula. However, family support after delivery increased the odds of feeding water to newborns. CONCLUSIONS: The multiple factors contributing to the high prevalence of prelacteal feeding behaviors stress the need for early and appropriate breastfeeding interventions in Vietnam, particularly during routine healthcare contacts. Improving breastfeeding practices during the first days of an infant's life could be achieved by improving knowledge and confidence of mothers through appropriate perinatal counseling and support. Ensuring that health facilities integrate these practices into routine ante-natal care and post-delivery management is critical.
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Lactancia Materna/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Relaciones Madre-Hijo/psicología , Apoyo Social , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Modelos Logísticos , Masculino , Persona de Mediana Edad , Embarazo , Atención Prenatal , Prevalencia , Vietnam/epidemiologíaRESUMEN
To compare the rate of positive thyroid peroxidase antibodies (TPO Ab) between women with different polycystic ovary syndrome (PCOS) phenotypes and women without PCOS. This is a retrospective cohort study. Women with PCOS at My Duc Hospital between June 1, 2020, and March 27, 2021, were matched with non-PCOS women by age. TPO Ab (cut-off: 34 IU/mL) and thyroid-stimulating hormone (TSH) levels were measured as markers of Hashimoto thyroiditis and thyroid function, respectively. One thousand eight hundred eight infertile women were included, 904 with PCOS (mean age 29.0 ± 3.58 years) and 904 without PCOS (29.1 ± 3.4 years; controls). Women with PCOS had a higher body mass index (22.8 ± 3.84 vs. 19.9 ± 2.23 kg/m2, p < 0.001), but most were not overweight/obese. Rates of positive TPO Ab in women with versus without PCOS were 8.2% and 8.4%, respectively (p = 0.932). Rates of positive TPO Ab in patients with PCOS phenotype A, B, C, or D were not statistically different (7.5%, 2.9%, 20.0%, and 7.8%, respectively). Median TSH concentrations were similar in the PCOS and control groups (1.84 mIU/L vs. 1.78 mIU/L, respectively; p = 0.194). Based on a linear regression model, there was no correlation between either BMI or the estradiol to progesterone ratio and TPO Ab status. In a large population of infertile women with PCOS who were mostly lean patients, rates of positive TPO Ab across all four PCOS phenotypes did not differ significantly from those in women without PCOS. These findings did not support the hypothesis that PCOS is a risk factor for Hashimoto thyroiditis.
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Enfermedad de Hashimoto , Infertilidad Femenina , Síndrome del Ovario Poliquístico , Humanos , Femenino , Adulto , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/epidemiología , Estudios Retrospectivos , Tirotropina , Yoduro PeroxidasaRESUMEN
Understanding HIV-related behaviours and the factors that influence these behaviours among people living with HIV (PLHIV) is critical to the design of effective HIV-prevention strategies; however, this subject has yet to receive the attention it deserves in Vietnam. Given that greater proportions of new HIV infections in the country stem from heterosexual transmission, it is essential to examine the sexual behaviours of Vietnamese PLHIV. The purpose of this qualitative study was to explore the sexual behaviour of individuals following HIV diagnosis and to gain insight into how and why HIV diagnosis affects sexual practices and relationships. Seventy PLHIV in Thaibinh province participated in semi-structured, in-depth interviews. Qualitative data were supported by a quantitative questionnaire on demographics and sexual and drug use history. Nearly all of the participants reported adopting safer sexual practices following HIV diagnosis by using condoms consistently and reducing the number of sex partners. This was true for injecting drug users, female sex workers, unmarried individuals and participants in both HIV serodiscordant and seroconcordant marriages. Motivations for adopting these preventive measures included avoiding HIV transmission, reinfection or cross-resistance as well as preservation of one's own health. Due to stigma, depression, fear of transmission, health status and/or drug addiction, HIV diagnosis dramatically impacted the sexual health of most participants by reducing sexual desire, pleasure and frequency. Implications for HIV prevention and care programmes and policies in Vietnam are discussed.
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Antirretrovirales/uso terapéutico , Infecciones por VIH/epidemiología , Promoción de la Salud/métodos , Conducta Sexual/estadística & datos numéricos , Adolescente , Adulto , Condones/estadística & datos numéricos , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/psicología , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Conducta Sexual/psicología , Parejas Sexuales/psicología , Vietnam/epidemiología , Adulto JovenRESUMEN
A comprehensive, mapped social determinants of health (SDH) taxonomy in machine readable format was developed. The framework is intended to facilitate the extraction of social risk factors (SRFs) out of electronic health record (EHR) data and categorize them by domain and determinant to facilitate interpretation. Where other SDH frameworks have been focused on data input, this framework is designed from a data extraction point of view using EHR data in conjunction with published literature, public health policy documents, and official crosswalk maps. Frameworks developed by leading public health organizations were reviewed and synthesized to create an SDH framework comprising of 97 distinct SRFs organized under 16 domains. 2,329 medical codes across three standardized medical vocabularies, 10,896 free-text diagnosis descriptors, and 25 health insurance keywords were mapped to individual SRFs in the SDH framework. The framework is available as an open-source resource in Python dictionary or JSON format.
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Registros Electrónicos de Salud , Determinantes Sociales de la Salud , Humanos , Salud PúblicaRESUMEN
BACKGROUND: The key to fishery management is knowing the appropriate reproductive strategies of the targeted fish. For most gobiid species, the iteroparous pattern is dominant compared to semelparity. Albeit Butis koilomatodon plays an important role in the Mekong Delta's food supply, its reproductive biological data have not been known. Hence, this study was conducted to provide new fundamental knowledge of reproductive traits of Butis koilomatodon in the Mekong Delta. RESULTS: A total of 1314 individuals (903 males and 411 females) were monthly collected by bottom gill nets from July 2019 to June 2020 at six sampling sites along estuarial and coastal regions, from Tra Vinh to Ca Mau provinces, southern of Vietnam. pH and salinity of these six sampling sites are 7.72-7.93 pH and 11.17-26.17, respectively. The pH varies with sites, but not seasons; whereas a reverse case is found in salinity. Different types of oocytes are found in histological specimens of ovaries prove that B. koilomatodon is a multi-spawner. The gonadosomatic index value, together with the monthly presence of mature ovaries reveal that this species spawns throughout the year. The length at first mature male Butis koilomatodon (5.1-8.6 cm) is higher than that of females (4.8-6.7 cm), except in Hoa Binh and Dong Hai. Batch fecundity (3085 to 32,087 eggs/female) increases with fish weight (1.48-12.30 g) and length (4.8-9.0 cm) due to high determination values (r2 > 0.6). CONCLUSION: Knowledge of reproductive traits gained from this study was a reference source for future studies and helped manage this species' resources.
RESUMEN
Surface-initiated atom transfer radical polymerization (SI-ATRP) has been used to grow brushes of poly(2-(methacryloyloxy)ethyl phosphorylcholine) (PMPC) from silicon wafers using a polyelectrolytic macroinitiator on planar silicon wafers. Film thicknesses of up to 450 nm were possible within 21 h, and the effect of adding activator and deactivator species on the brush growth rate was studied. The solvation of PMPC brushes in mixed alcohol/water solvents was investigated using in situ ellipsometry. Co-nonsolvency (a re-entrant swelling transition) behavior was observed in water/ethanol binary mixtures; that is, the PMPC brushes were highly swollen in either pure ethanol or water but became deswollen at specific ethanol-rich solvent compositions. A similar effect was obtained with water/2-propanol mixtures, except that in this case pure 2-propanol was not a particularly good solvent for the PMPC chains. However, co-nonsolvency was not observed for water/methanol binary mixtures, since the brushes remained well swollen at all solvent compositions. This is consistent with prior reports of co-nonsolvency effects in both PMPC gels and linear PMPC chains. However, this is the first report of this phenomenon for PMPC brushes and one of the first examples of co-nonsolvency observed for any polymer brush system. A direct comparison of brush and gel swelling reveals an approximate power-law relationship between the equilibrium volumes of these two systems at various solvent compositions, which is interpreted by treating the brush layer as a surface-attached gel. We believe this to be the first quantitative comparison of brush and gel swelling using the same polymer under the same conditions. The kinetics of the PMPC brush response to adjustment of the alcohol/water composition is relatively fast, with the brush volume change occurring on time scales of less than 1 min as judged by in situ ellipsometry.