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1.
Langmuir ; 40(17): 9097-9107, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38640355

RESUMO

The concurrent utilization of an adsorbent and absorbent for carbon dioxide (CO2) adsorption with synergistic effects presents a promising technique for CO2 capture. Here, 1-butyl-3-methylimidazole acetate ([Bmim][Ac]), with a high affinity for CO2, and the molecular sieve SAPO-34 were selected. The impregnation method was used to composite the hybrid samples of [Bmim][Ac]/SAPO-34, and the pore structure and surface property of prepared samples were characterized. The quantity and kinetics of the sorbed CO2 for loaded samples were measured using thermogravimetric analysis. The study revealed that SAPO-34 could retain its pristine structure after [Bmim][Ac] loading. The CO2 uptake of the loaded sample was 1.879 mmol g-1 at 303 K and 1 bar, exhibiting a 20.6% rise compared to that of the pristine SAPO-34 recording 1.558 mmol g-1. The CO2 uptake kinetics of the loaded samples were also accelerated, and the apparent mass transfer resistance for CO2 sorption was significantly reduced by 11.2% compared with that of the pure [Bmim][Ac]. The differential scanning calorimetry method revealed that the loaded sample had a lower CO2 desorption heat than that of the pure [Bmim][Ac], and the CO2 desorption heat of the loaded samples was between 30.6 and 40.8 kJ mol-1. The samples exhibited good cyclic stability. This material displays great potential for CO2 capture applications, facilitating the reduction of greenhouse gas emissions.

2.
J Am Chem Soc ; 146(12): 7971-7978, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483538

RESUMO

We describe a nickel-catalyzed carbonylative cross-coupling of unactivated secondary alkyl electrophiles with the organozinc reagent at atmospheric CO gas, thus allowing the expedient construction of unsymmetric dialkyl ketones with broad functional group tolerance. The leverage of a newly developed NN2-pincer type ligand enables the chemoselective three-component carbonylation by overcoming the competing Negishi coupling, the undesired ß-hydride elimination, and dehalogenation of alkyl iodides side pathways. Both alkyl iodides and alkyl tosylates are compatible in the single electron transfer involved mechanism.

3.
Org Biomol Chem ; 22(12): 2380-2383, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38436087

RESUMO

A nickel-catalyzed acylation of vinylpyridines with CO at atmospheric pressure is reported, allowing for an expedient approach to synthesize ß-acyl pyridine derivatives with high regio- and chemoselectivity. The electron-withdrawing property of pyridine plays pivotal roles in activating the alkenyl group, thereby facilitating this carbonylative process. In addition to vinylpyridines, other alkenylheterocycles such as thiazole and quinoline were also suitable for this method.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38498743

RESUMO

Functional near-infrared spectroscopy (fNIRS) seems opportune for neurofeedback in robot-assisted rehabilitation training due to its noninvasive, less physical restriction, and no electromagnetic disturbance. Previous research has proved the cross-session reliability of fNIRS responses to non-motor tasks (e.g., visual stimuli) and fine-motor tasks (e.g., finger tapping). However, it is still unknown whether fNIRS responses remain reliable 1) in gross-motor tasks, 2) within a training session, and 3) for different training parameters. Hence, this study aimed to investigate the within-session reliability of fNIRS responses to gross-motor tasks for different training parameters. Ten healthy participants were recruited to conduct right elbow extension-flexion in three robot-assisted modes. The Passive mode was fully motor-actuated, while Active1 and Active2 modes involved active engagement with different resistance levels. FNIRS data of three identical runs were used to assess the within-session reliability in terms of the map- ( R2 ) and cluster-wise ( Roverlap ) spatial reproducibility and the intraclass correlation (ICC) of temporal features. The results revealed good spatial reliability ( R2 up to 0.69, Roverlap up to 0.68) at the subject level. Besides, the within-session temporal reliabilities of Slope, Max/Min, and Mean were between good and excellent ( ICC < 0.86). We also found that the within-session reliability was positively correlated with the intensity of the training mode, except for the temporal reliability of HbO in Active2 mode. Overall, our results demonstrated good within-session reliability of fNIRS responses, suggesting fNIRS as reliable neurofeedback for constructing closed-loop robot-assisted rehabilitation systems.


Assuntos
Robótica , Humanos , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Extremidade Superior
5.
J Org Chem ; 89(5): 3123-3132, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377547

RESUMO

Introducing degrees of unsaturation into small molecules is a central transformation in organic synthesis. A strategically useful category of this reaction type is the conversion of alkanes into alkenes for substrates with an adjacent electron-withdrawing group. An efficient strategy for this conversion has been deprotonation to form a stabilized organozinc intermediate that can be subjected to α,ß-dehydrogenation through palladium or nickel catalysis. This general reactivity blueprint presents a window to uncover and understand the reactivity of Pd- and Ni-enolates. Within this context, it was determined that ß-hydride elimination is slow and proceeds via concerted syn-elimination. One interesting finding is that ß-hydride elimination can be preferred to a greater extent than C-C bond formation for Ni, more so than with Pd, which defies the generally assumed trends that ß-hydride elimination is more facile with Pd than Ni. The discussion of these findings is informed by KIE experiments, DFT calculations, stoichiometric reactions, and rate studies. Additionally, this report details an in-depth analysis of a methodological manifold for practical dehydrogenation and should enable its application to challenges in organic synthesis.

6.
Adv Sci (Weinh) ; 11(16): e2308077, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403462

RESUMO

The foreign body response (FBR) to implanted biomaterials and biomedical devices can severely impede their functionality and even lead to failure. The discovery of effective anti-FBR materials remains a formidable challenge. Inspire by the enrichment of glutamic acid (E) and lysine (K) residues on human protein surfaces, a class of zwitterionic polypeptide (ZIP) hydrogels with alternating E and K sequences to mitigate the FBR is prepared. When subcutaneously implanted, the ZIP hydrogels caused minimal inflammation after 2 weeks and no obvious collagen capsulation after 6 months in mice. Importantly, these hydrogels effectively resisted the FBR in non-human primate models for at least 2 months. In addition, the enzymatic degradability of the gel can be controlled by adjusting the crosslinking degree or the optical isomerism of amino acid monomers. The long-term FBR resistance and controlled degradability of ZIP hydrogels open up new possibilities for a broad range of biomedical applications.


Assuntos
Reação a Corpo Estranho , Hidrogéis , Animais , Hidrogéis/química , Camundongos , Materiais Biocompatíveis/química , Lisina/química , Primatas , Roedores , Ácido Poliglutâmico/química
7.
Langmuir ; 40(8): 4186-4197, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38358822

RESUMO

The dissolution of minerals within rock fractures is fundamental to many geological processes. Previous research on fracture dissolution has highlighted the significant role of buoyancy-driven convection leading to dissolution instability. Yet, the pore-scale mechanisms underlying this instability are poorly understood primarily due to the challenges in experimentally determining flow velocity and concentration fields. Here, we integrate pore-scale simulations with theoretical analysis to delve into the dissolution instability prompted by buoyancy-driven convection in a radial horizontal geometry. Initially, we develop a pore-scale modeling approach incorporating gravitational effects, subsequently validating it through experiments. We then employ pore-scale numerical simulations to elucidate the 3D intricacies of flow-dissolution dynamics. Our findings reveal that a simple criterion can delineate the condition for the onset of buoyancy-driven dissolution instability. If the characteristic length falls below a critical threshold, dissolution remains stable. Conversely, exceeding this threshold leads to two distinct regimes: the unstable regime of the confined domain affected by the initial aperture and the unstable regime of the semi-infinite domain independent of the initial aperture where the instability is no longer influenced by the lower boundary. We demonstrate that the pore-scale mechanism for this instability is due to the concentration boundary layer attaining a gravitationally unstable critical thickness. Through theoretical analysis of this layer and the time scales of diffusion and advection, we establish a theoretical model to predict where the dissolution instability occurs. This model aligns closely with our numerical simulations and experimental data across diverse conditions. Our work improves the understanding of buoyancy-driven dissolution instability in radial horizontal geometry. It is also of practical significance in understanding cavity formation in karst hydrology and preventing leaks in geological CO2 storage.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38330572

RESUMO

Objective: To explore the relationship between the expression of placental growth factor (PLGF) and Zeste homolog enhancer 2 (EZH2) in placental tissues of women with gestational diabetes (GDM), placental function, and pregnancy outcome. Methods: Select 100 women with GDM diagnosed in our hospital from January 2019 to May 2020 as the GDM group and 100 women with normal pregnancy at the same time as the control group. Detection and analysis of the expression levels of PLGF and EZH2 proteins in placental tissue after delivery of the two components. Observation of the expression of different PLGF and EZH2 proteins using an electron microscope, and analyze the ultrastructural changes in placental tissue of women with GDM. Finally, assess the differences in pregnancy outcomes. Results: The expression intensity of PLGF protein in the GDM group was higher than that in the control group (P < .001), and the expression intensity of EZH2 protein in the GDM group was lower than that in the control group (P < .001); the positive rate of PLGF protein in the GDM group was 67.00% higher than that of the control group 35.00% (P < .001), the positive rate of EZH2 protein in the GDM group was 15.00% lower than 33.00% in the control group (P = .003); the placental ultrastructural change rate of PLGF-positive GDM women was 71.64% higher than that in the negative expression group 45.45 % (P = .011); the placental ultrastructural change rate of EZH2 protein-positive GDM mothers was 33.33% lower than that of negative expression of A mixed 68.24% (P = .01); the incidence of premature infants (26.87%) and fetal respiratory distress (13.43%) in the PLGF-positive GDM group, the rate was higher than that in the negative expression group (9.09%, 0%) (P = .027, .04); the incidence of preterm infants in the EZH2 protein-positive GDM group (0.00%) was lower than that in the negative expression group (24.71%) (P = .03). Conclusion: The expression of PLGF is up-regulated and the expression of EZH2 is down-regulated in the placental tissue of GDM women, which causes ultrastructural changes in the placental tissue and increases the incidence of preterm birth and fetal respiratory distress to a certain extent.

9.
Angew Chem Int Ed Engl ; : e202318991, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252658

RESUMO

ß-Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt-catalyzed enantioselective reductive addition reaction of ketimine using α-chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched ß-quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky-type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late-stage modification of drug candidates.

10.
Angew Chem Int Ed Engl ; 63(7): e202316012, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38164694

RESUMO

Chromium-catalyzed enantioselective Nozaki-Hiyama-Kishi (NHK) reaction represents one of the most powerful approaches for the formation of chiral carbon-heteroatom bond. However, the construction of sterically encumbered tetrasubstituted stereocenter through NHK reaction still posts a significant challenge. Herein, we disclose a cobalt-catalyzed aza-NHK reaction of ketimine with alkenyl halide to provide a convenient synthetic approach for the manufacture of enantioenriched tetrasubstituted α-vinylic amino acid. This protocol exhibits excellent functional group tolerance with excellent 99 % ee in most cases. Additionally, this asymmetric reductive method is also applicable to the aldimine to access the trisubstituted stereogenic centers.

11.
Clin Interv Aging ; 19: 41-50, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38204961

RESUMO

Purpose: Here, we introduce a novel strategy of awake unilateral biportal endoscopic (UBE) decompression, which applies conscious sedation combined with stepwise local anesthesia (LA) as an alternative to general anesthesia (GA). The study aims to evaluate the feasibility of awake UBE decompression for degenerative lumbar spinal stenosis (DLSS) in elderly patients. Patients and Methods: This retrospective study included 31 consecutive patients who received awake UBE decompression for DLSS in our institution from January 2021 to March 2022. Clinical results were evaluated using patient-reported outcomes measures (PROM) including visual analog scale for leg pain (VAS-LP), Oswestry Disability Index (ODI), and modified MacNab criteria. The anesthesia effectiveness and intraoperative experience were evaluated by intraoperative VAS and satisfaction rating system. Results: UBE decompression was successfully performed in all patients under LA combined with conscious sedation. 26 (83.9%) patients rated the intraoperative experience as satisfactory (excellent or good) and 5 (16.1%) as fair. The mean intraoperative VAS was 3.41±1.26. The VAS and ODI at each follow-up stage after surgery were significantly improved compared to preoperative scores (p < 0.01). At the last follow-up, 28 patients (90.3%) classified the surgical outcome as good or excellent, and 3 (9.7%) as fair. There were no serious complications or adverse reactions observed in the study. Conclusion: Our preliminary results suggest that awake UBE decompression is a feasible and promising alternative for elderly patients with DLSS.


Assuntos
Anestesia Local , Estenose Espinal , Idoso , Humanos , Estudos de Viabilidade , Descompressão Cirúrgica , Estudos Retrospectivos , Estenose Espinal/cirurgia , Vigília , Vértebras Lombares/cirurgia
12.
Bioact Mater ; 34: 482-493, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38292409

RESUMO

Implantable biomaterials and biosensors are integral components of modern medical systems but often encounter hindrances due to the foreign body response (FBR). Herein, we report an albumin coating strategy aimed at addressing this challenge. Using a facile and scalable silane coupling strategy, human serum albumin (HSA) is covalently grafted to the surface of polydimethylsiloxane (PDMS) implants. This covalently grafted albumin coating remains stable and resistant to displacement by other proteins. Notably, the PDMS with covalently grafted HSA strongly resists the fibrotic capsule formation following a 180-day subcutaneous implantation in C57BL/6 mice. Furthermore, the albumin coating led to reduced recruitment of macrophages and triggered a mild immune activation pattern. Exploration of albumin coatings sourced from various mammalian species has shown that only HSA exhibited a promising anti-FBR effect. The albumin coating method reported here holds the potential to improve and extend the function of silicone-based implants by mitigating the host responses to subcutaneously implanted biomaterials.

13.
IEEE Trans Image Process ; 33: 1487-1496, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37037237

RESUMO

Traditional CNN-based pipelines for panoptic segmentation decompose the task into two subtasks, i.e., instance segmentation and semantic segmentation. In this way, they extract information with multiple branches, perform two subtasks separately and finally fuse the results. However, excessive feature extraction and complicated processes make them time-consuming. We propose IDNet to decompose panoptic segmentation at information level. IDNet only extracts two kinds of information and directly completes panoptic segmentation task, saving the efforts to extract extra information and to fuse subtasks. By decomposing panoptic segmentation into category information and location information and recomposing them with a serial pipeline, the process for panoptic segmentation is simplified greatly and unified with regard to stuff and things. We also adopt two correction losses specially designed for our serial pipeline, guaranteeing the overall predicting performance. As a result, IDNet strikes a better balance between effectiveness and efficiency, achieving the fastest inference speed of 24.2 FPS at a resolution of 800×1333 on a Tesla V100 GPU and a PQ of 43.8, which is comparable in one-stage CNN-based methods. The code will be released at https://github.com/AronLin/IDNet.

14.
Nat Chem ; 16(3): 398-407, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082178

RESUMO

Unnatural chiral α-tertiary amino acids containing two different carbon-based substituents at the α-carbon centre are widespread in biologically active molecules. This sterically rigid scaffold is becoming a growing research interest in drug discovery. However, a robust protocol for chiral α-tertiary amino acid synthesis remains scarce due to the challenge of stereoselectively constructing sterically encumbered tetrasubstituted stereogenic carbon centres. Herein we report a cobalt-catalysed enantioselective aza-Barbier reaction of ketimines with various unactivated alkyl halides, including alkyl iodides, alkyl bromides and alkyl chlorides, enabling the formation of chiral α-tertiary amino esters with a high level of enantioselectivity and excellent functional group tolerance. Primary, secondary and tertiary organoelectrophiles are all tolerated in this asymmetric reductive addition protocol, which provides a complementary method for the well-exploited enantioselective nucleophilic addition with moisture- and air-sensitive organometallic reagents. Moreover, the three-component transformation of α-ketoester, amine and alkyl halide represents a formal asymmetric deoxygenative alkylamination of the carbonyl group.

15.
Ultrasound Q ; 40(1): 39-45, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37545088

RESUMO

ABSTRACT: The objective of this study is to develop and validate the performance of 2 ultrasound (US) feature-guided machine learning models in distinguishing cervical lymphadenopathy. We enrolled 705 patients whose US characteristics of lymph nodes were collected at our hospital. B-mode US and color Doppler US features of cervical lymph nodes in both cohorts were analyzed by 2 radiologists. The decision tree and back propagation (BP) neural network were developed by combining clinical data (age, sex, and history of tumor) and US features. The performance of the 2 models was evaluated by calculating the area under the receiver operating characteristics curve (AUC), accuracy value, precision value, recall value, and balanced F score (F1 score). The AUC of the decision tree and BP model in the modeling cohort were 0.796 (0.757, 0.835) and 0.854 (0.756, 0.952), respectively. The AUC, accuracy value, precision value, recall value, and F1 score of the decision tree in the validation cohort were all higher than those of the BP model: 0.817 (0.786, 0.848) vs 0.674 (0.601, 0.747), 0.774 (0.737, 0.811) vs 0.702 (0.629, 0.775), 0.786 (0.739, 0.833) vs 0.644 (0.568, 0.720), 0.733 (0.694, 0.772) vs 0.630 (0.542, 0.718), and 0.750 (0.705, 0.795) vs 0.627 (0.541, 0.713), respectively. The US feature-guided decision tree model was more efficient in the diagnosis of cervical lymphadenopathy than the BP model.


Assuntos
Linfadenopatia , Humanos , Estudos Retrospectivos , Linfadenopatia/diagnóstico , Ultrassonografia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Aprendizado de Máquina
16.
Adv Mater ; 36(8): e2308370, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37938798

RESUMO

Wide-bandgap (WBG) perovskite solar cells hold tremendous potential for realizing efficient tandem solar cells. However, nonradiative recombination and carrier transport losses occurring at the perovskite/electron-selective contact (e.g. C60 ) interface present significant obstacles in approaching their theoretical efficiency limit. To address this, a sequential interface engineering (SIE) strategy that involves the deposition of ethylenediamine diiodide (EDAI2 ) followed by sequential deposition of 4-Fluoro-Phenethylammonium chloride (4F-PEACl) is implemented. The SIE technique synergistically narrows the conduction band offset and reduces recombination velocity at the perovskite/C60 interface. The best-performing WBG perovskite solar cell (1.67 eV) delivers a power conversion efficiency (PCE) of 21.8% and an impressive open-circuit voltage of 1.262 V. Moreover, through integration with double-textured silicon featuring submicrometer pyramid structures, a stabilized PCE of 29.6% is attained for a 1 cm2 monolithic perovskite/silicon tandem cell (certified PCE of 29.0%).

17.
Artigo em Inglês | MEDLINE | ID: mdl-38095763

RESUMO

PURPOSE: The DELIVER trial demonstrated the efficacy of dapagliflozin in reducing primary endpoint (cardiovascular (CV) mortality or worsening heart failure) for heart failure with mid-range ejection fraction (HFmrEF) and heart failure with preserved ejection fraction (HFpEF). This study assessed the economic and clinical effects of incorporating dapagliflozin into a standard treatment regimen for HFpEF and HFmrEF cases in China. METHODS: A multistate Markov model was used to assess the clinical and economic effects of adding dapagliflozin to the usual treatment regimen for HFpEF and HFmrEF. A log-logistic formula was used to represent the cumulative incidence of hospitalization, readmission, and CV mortality. A 5% annual discount was applied to all costs. The health outcome was the incremental cost-effectiveness ratio (ICER), measured using quality-adjusted life years (QALYs) and life years (LYs). The findings were examined using sensitivity and scenario analyses to assess robustness. RESULTS: In the HFpEF or HFmrEF population, the 11.2-year incremental QALYs was 0.15 and LYs was 0.2, yielding an ICER of $10,615.87 per QALY and $7,763.08 per LY. These ICER values are lower than China's per capita gross domestic product (GDP) of $12,752 in 2022. The one-way sensitivity analysis revealed that non-hospital CV death was the most influential parameter. Furthermore, there was a 68% chance that dapagliflozin was cost-effective as an additional treatment, given a willingness-to-pay limit of three times the GDP ($38,256). CONCLUSIONS: Dapagliflozin adjunctive therapy was cost-effective in patients with HFpEF or HFmrEF from the perspective of Chinese national insurance.

18.
Nat Commun ; 14(1): 6960, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907542

RESUMO

Transition metal-catalyzed carbonylative reaction with CO gas are among the central task in organic synthesis, enabling the construction of highly valuable carbonyl compound. Here, we show an earth-abundant nickel-catalyzed three-component tandem acylzincation/cyclization sequence of allene and alkylzinc reagent with 1 atm of CO under mild conditions. This protocol is featured by broad functional group tolerance with high reaction selectivity, providing a rapid and convenient synthetic method for the construction of diverse fully substituted benzotropone derivatives. Mechanistic studies reveal that the installation of a cyano group tethered to allene moiety enables the high regio- and stereoselectivity of this acylzincation of allene, allowing the selective formation of three consecutive C-C bonds in a highly efficient manner.

19.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003320

RESUMO

Hypericum perforatum (St. John's Wort) is a medicinal plant from the Hypericaceae family. Here, we sequenced the whole chloroplast genome of H. perforatum and compared the genome variation among five Hypericum species to discover dynamic changes and elucidate the mechanisms that lead to genome rearrangements in the Hypericum chloroplast genomes. The H. perforatum chloroplast genome is 139,725 bp, exhibiting a circular quadripartite structure with two copies of inverted repeats (IRs) separating a large single-copy region and a small single-copy region. The H. perforatum chloroplast genome encodes 106 unique genes, including 73 protein-coding genes, 29 tRNAs, and 4 rRNAs. Hypericum chloroplast genomes exhibit genome rearrangement and significant variations among species. The genome size variation among the five Hypericum species was remarkably associated with the expansion or contraction of IR regions and gene losses. Three genes-trnK-UUU, infA, and rps16-were lost, and three genes-rps7, rpl23, and rpl32-were pseudogenized in Hypericum. All the Hypericum chloroplast genomes lost the two introns in clpP, the intron in rps12, and the second intron in ycf3. Hypericum chloroplast genomes contain many long repeat sequences, suggesting a role in facilitating rearrangements. Most genes, according to molecular evolution assessments, are under purifying selection.


Assuntos
Clusiaceae , Genoma de Cloroplastos , Hypericum , Hypericum/genética , Clusiaceae/genética , Sequência de Bases , Sequências Repetitivas de Ácido Nucleico , Filogenia , Evolução Molecular
20.
Hum Reprod ; 38(12): 2489-2498, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37759343

RESUMO

STUDY QUESTION: Does ambient temperature exposure affect outcomes including clinical pregnancy and live birth in women undergoing IVF? SUMMARY ANSWER: Both extreme cold and hot ambient temperatures were significantly associated with adverse pregnancy outcomes of IVF cycles. WHAT IS KNOWN ALREADY: Heat exposure has been linked to adverse pregnancy outcomes worldwide. However, the effect of ambient temperature on infertile women undergoing IVF treatment is unclear. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study was conducted from a database of 3452 infertile women who underwent their first fresh or frozen embryo transfer in the Shanghai First Maternity and Infant Hospital from April 2016 to December 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: Daily mean ambient temperature exposure for each patient was obtained based on their residential address. Temperature-stratified multiple logistic regression analysis was performed to investigate associations between temperature exposure and pregnancy outcomes after controlling for confounders. Vulnerable sub-groups were identified using forest plots. MAIN RESULTS AND THE ROLE OF CHANCE: The clinical pregnancy rate and live birth rate were 45.7% and 37.1%, respectively. Regarding clinical pregnancy, a higher temperature during cold weather was significantly associated with a higher pregnancy rate in the period about 11 weeks before ovarian stimulation (adjusted odds ratio (aOR) = 1.102, 95% CI: 1.012-1.201). Regarding live birth, an increased temperature during cold weather was significantly related to a higher live birth rate in the period after confirmation of clinical pregnancy or biochemical pregnancy, with the aORs of 6.299 (95% CI: 3.949-10.047) or 10.486 (95% CI: 5.609-19.620), respectively. However, a higher temperature during hot weather was negatively associated with the live birth rate in the periods after confirmation of clinical pregnancy or biochemical pregnancy, with the aORs at 0.186 (95% CI: 0.121-0.285) or 0.302 (95% CI: 0.224-0.406), respectively. Moreover, the decline in live birth rates during cold and hot weather was accompanied by increased rates of early miscarriage (P < 0.05). Stratified analyses identified susceptibility characteristics among the participants. LIMITATIONS, REASONS FOR CAUTION: Climate monitoring data were used to represent individual temperature exposure levels according to the patient's residential address in the study. We were not able to obtain information of personal outdoor activity and use of indoor air conditioners in this retrospective study, which may affect actual temperature exposure. WIDER IMPLICATIONS OF THE FINDINGS: This study highlights that the ambient temperature exposure should be taken into account during IVF treatment and afterwards. There is a need to be alert to extremes in cold and hot ambient temperatures, especially during the period of follicle development and pregnancy. With this knowledge, clinicians can scientifically determine the timing of IVF treatment and reinforce patients' awareness of self-protection to minimize adverse pregnancy outcomes associated with extreme temperatures. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a grant from the Clinical Research Plan of Shanghai Hospital Development Center [SHDC2020CR4080], a grant from the Science and Technology Commission of Shanghai Municipality [19411960500], and two grants from the National Natural Science Foundation of China [81871213, 81671468]. B.W.M. is supported by a NHMRC Investigator grant (GNT1176437). B.W.M. reports consultancy for ObsEva, and research grants from Merck KGaA, Ferring and Guerbet. The other authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Feminina , Resultado da Gravidez , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Temperatura , Infertilidade Feminina/terapia , Resultado do Tratamento , China/epidemiologia , Fertilização in vitro/métodos , Taxa de Gravidez , Coeficiente de Natalidade , Nascido Vivo
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