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1.
Reprod Biomed Online ; 49(3): 104076, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38959531

RESUMEN

RESEARCH QUESTION: Is low serum 25-hydroxyvitamin D (25(OH)D) associated with an increased risk of miscarriage in women who presented with threatened miscarriage to the Early Pregnancy Assessment Clinic (EPAC)? DESIGN: This was a secondary retrospective analysis using archived serum samples from a randomized, double-blind, placebo-controlled trial. Stored serum samples from 371 women presenting to the EPAC with threatened miscarriage during the first trimester were assayed for 25(OH)D by liquid chromatography-mass spectrometry. RESULTS: The overall miscarriage rate was 45/371 (12.1%) in the whole cohort. After grouping vitamin D insufficiency and vitamin D sufficiency together into a 'non-deficient' group and excluding participants who underwent termination of pregnancy, there was no difference in the miscarriage rate between those who were vitamin D deficient compared with those who were not (25/205, 12.2% versus 20/157, 12.7%, P= 0.877, odds ratio 0.951, 95% CI 0.507-1.784). When analysed according to the number of gestational weeks, the miscarriage rate was significantly higher in the vitamin D non-deficient group than the vitamin D-deficient group in women who presented at 6 gestational weeks or earlier (13/33 [39.4%] versus 10/58 [17.2%], P= 0.019), but there were no statistically significant differences between the two groups presenting at later gestations. There was no difference in the vitamin D level in women who had a miscarriage compared with those who had a live birth (48 [37-57] versus 47 [37-58] nmol/l, P= 0.725 median [25th-75th percentile]). CONCLUSIONS: A low serum vitamin D concentration was not associated with an increased risk of miscarriage in women with threatened miscarriage presenting to the EPAC.

2.
Am J Obstet Gynecol MFM ; : 101423, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38977063

RESUMEN

BACKGROUND: Seven days of antibiotics are recommended in the setting of preterm premature rupture of membranes (PPROM) to promote latency. Azithromycin has generally replaced a seven-day course of erythromycin in current clinical practice. Azithromycin clears from plasma quickly and concentrates in local tissue which is why daily dosing is not always needed and local tissue, rather than plasma, concentrations are used to determine dosing. Based on limited pharmacokinetic studies in pregnancy, 1g one time dose of azithromycin may not maintain local (amniotic fluid) drug concentrations above minimum inhibitory concentrations (MIC50) for common genitourinary pathogens (50-500ng/ml). OBJECTIVE: We aim to compare the pharmacokinetics of one-time vs daily dosing of azithromycin in the setting of preterm pre-labor rupture of membranes (PPROM) STUDY DESIGN: This is a randomized clinical trial of singletons with PPROM randomized to 1gram oral azithromycin once or 500mg oral azithromycin daily x7 days. Primary outcome was amniotic fluid azithromycin concentrations over 8 days. Secondary outcomes included plasma azithromycin trough concentrations. Plasma was collected at time points 1-4hrs and 12-24hrs after first dose, and then every 24hrs through 8 days. Amniotic fluid was collected opportunistically throughout the day noninvasively with Always Flex-foam pads. We aimed to enroll 20 participants to achieve N=5 still pregnant through 8 days in each group. Continuous variables compared with Mann Whitney U test and relationship between azithromycin concentration and time assessed with linear regression. RESULTS: The study was halted after N=6 enrolled due to lagging enrollment, with 3 in each group. The mean gestational age of enrollment was 27.1±1.7weeks in the 1g group and 31.0±1.4 weeks in the 500mg daily group. One participant in each group had latency to delivery >7days. Regarding amniotic fluid azithromycin concentration, there was a difference in change in amniotic fluid azithromycin concentration over time between groups (p<0.001). Amniotic fluid concentration of azithromycin was relatively stable in the 1g once group (B=-0.07 (-0.44 - 0.31), p=0.71), in contrast, amniotic fluid concentration (ng/ml) increased over time (hours) in the 500mg daily group (B=1.3 (0.7 - 1.9), p<0.001). By ≥96hours median amniotic fluid levels of azithromycin were lower in the 1g once dosing group (median 11[7-56]) compared to 500mg daily (median 46 [23-196]), with a median difference -27 (-154 to -1), p=0.03. In plasma, there was higher azithromycin concentration during the first 24hrs with 1g once vs 500mg daily (median difference 637ng/ml (101-1547), p=0.01), however by ≥96hrs plasma azithromycin declined and was virtually undetectable in the 1g once group, while trough plasma levels in the 500mg remained elevated (median difference -207ng/ml (-271 to -155), p=0.03). CONCLUSION: 500mg daily dosing of azithromycin maintains higher amniotic fluid concentrations, and more consistently greater than common MICs, over eight days compared to 1g once in the setting of PPROM.

3.
Org Lett ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016380

RESUMEN

In this letter, we disclose the anodic oxidation of oxamic acids in the presence of Et3N·3HF as a practical, scalable, and robust method to rapidly access carbamoyl fluorides from readily available and stable precursors. The simplicity of this method also led us to develop the first flow electrochemical preparation of carbamoyl fluorides, demonstrating scale-up feasibility as a proof of concept.

4.
J Am Chem Soc ; 146(28): 18836-18840, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38954772

RESUMEN

Assembling molecular machines into crystals provides a way to harness their power on large length scales, but the development of a crystal analogue to a molecular motor remains a challenge. The molecule (Z)-5-(anthracen-9-ylmethylene)-3-butylthiazolidine-2,4-dione (C4-ATD) has E and Z isomers with strongly overlapping absorption spectra. This spectroscopic property allows both Z → E and E → Z photoisomerization reactions to be driven by a single light source, and simulations indicate this property can provide a route to robust oscillatory motion. Reprecipitation in an aqueous surfactant enables the growth of single crystal microwires that exhibit continuous mechanical oscillations under a wide range of illumination conditions, including ambient solar irradiation. Molecular crystal motors provide a new approach for transforming continuous light into oscillatory mechanical motion.

5.
ACS Omega ; 9(20): 22508, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38799350

RESUMEN

[This corrects the article DOI: 10.1021/acsomega.4c00411.].

6.
ACS Omega ; 9(14): 16563-16571, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38617675

RESUMEN

Water-free reflux condensers, which use convective cooling from the surrounding air to condense vapors, avoid the need for cooling water, which is more sustainable than water-cooled condensers, and eliminates the risk of flooding, but these devices are newer and less familiar to many chemists, who may never have used them before. To facilitate the shift to water-free condensers, several types of water-free condensers (simple glass tube, Vigreux column, Condensyn, Findenser, and air-cooled Dimroth) were characterized using three different solvents (ethyl acetate, acetone, and tetrahydrofuran) under both gentle and vigorous refluxing conditions to compare their relative performance and determine the condensing capacity/failure point. In addition to experimentally quantifying the performance of each condenser both gravimetrically and via infrared thermal imaging, energy-balance models were developed to gain insight into which factors were most important in driving their performance. Several of the water-free condensers, including the Findenser, Condensyn, and air-cooled Dimroth condenser, were shown to provide suitable performance for most refluxing operations.

7.
ACS Omega ; 9(10): 11266-11272, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38497006

RESUMEN

Organic molecules that undergo supercooling can provide the basis for novel stimuli-responsive materials, but the number of such compounds is limited. Results in this paper show that the stable organic radical 2,2,6,6-tetramethyl-1-piperidine-1-oxyl (TEMPO) can form a stable supercooled liquid (SCL). Upon melting and cooling back to room temperature, the TEMPO SCL can persist for months, even after mild physical agitation. Its high vapor pressure can enable crystal growth at remote locations within the sample container over the course of days. Optical, electron paramagnetic resonance, and birefringence measurements show no evidence of new chemical species or partially ordered phases in the supercooled liquid. TEMPO's free radical character permits absorption of visible light that can drive photothermal melting to form the SCL, while a single nanosecond light pulse can initiate recrystallization of the SCL at some later time. This capability enables all-optical switching between the solid and the SCL phases. The physical origin of TEMPO's remarkable stability as an SCL remains an open question, but these results suggest that organic radicals comprise a new class of molecules that can form SCLs with potentially useful properties.

9.
Langmuir ; 40(8): 4054-4062, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38353460

RESUMEN

2-Azidoanthracene (2N3-AN) can act as a photochemical source of N2 gas when dissolved in an optically transparent polymer such as poly(methyl methacrylate) (PMMA). Irradiation at 365 or 405 nm of a 150 µm-thick polymer film submerged in water causes the rapid appearance of a surface layer of bubbles. The rapid appearance of surface bubbles cannot be explained by normal diffusion of N2 through the polymer and likely results from internal gas pressure buildup during the reaction. For an azide concentration of 0.1 M and a light intensity of 140 mW/cm2, the yield of gas bubbles is calculated to be approximately 40%. The dynamics of bubble growth depend on the surface morphology, light intensity, and 2N3-AN concentration. A combination of nanoscale surface roughness, high azide concentration, and high light intensity is required to attain the threshold N2 gas density necessary for rapid, high-yield bubble formation. The N2 bubbles adhered to the PMMA surface and survived for days under water. The ability to generate stable gas bubbles "on demand" using light permits the demonstration of photoinduced flotation and patterned bubble arrays.

10.
Clin Transl Sci ; 17(3): e13721, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38421210

RESUMEN

Transgender women may have concerns of drug interactions between feminizing hormone therapy (FHT) and antiretrovirals, leading to nonadherence. This randomized, three-period crossover, open-label, phase I trial assessed the effects of doravirine (DOR) and tenofovir disoproxil fumarate (TDF) on the pharmacokinetics (PKs) of estradiol, spironolactone, and total testosterone and vice versa in healthy transgender women. Volunteers were randomized 1:1 into two sequences containing three treatment groups (DOR, lamivudine [3TC], and TDF alone; estradiol, spironolactone, and placebo; and DOR/3TC/TDF, estradiol, and spironolactone). Eight subjects enrolled in the study and six had completed all study periods. The geometric mean ratios for DOR area under the concentration-time curve from zero to last measured concentration (AUC0-last ), maximum concentration (Cmax ), and concentration at 24 h (C24 ) were similar. However, tenofovir (TFV) AUC0-last , Cmax , and C24 moderately increased by 14%-38%. Last, estradiol AUC0-last , Cmax , and C24 were increased by 10%-13%. Whereas most 90% confidence intervals did not meet the bioequivalence bounds of 80%-125%, the point estimates fell within the intervals. Log-transformed DOR, TFV, and estradiol PK parameters computed with and without co-administration were not statistically different (p > 0.05). There were no serious adverse events. There is not a clinically significant impact of FHT on DOR/TFV PKs. Similarly, there is no observed impact on estradiol PKs and total testosterone following use of DOR/3TC/TDF.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Piridonas , Personas Transgénero , Triazoles , Humanos , Femenino , Tenofovir/efectos adversos , Estudios Cruzados , Espironolactona , Lamivudine , Estradiol , Testosterona , Fármacos Anti-VIH/efectos adversos , Infecciones por VIH/tratamiento farmacológico
11.
J Assist Reprod Genet ; 41(2): 465-472, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38183536

RESUMEN

PURPOSE: This study aimed to optimize the non-invasive preimplantation genetic testing for aneuploidy (niPGT-A) in the laboratory by comparing two collection timing of the spent culture medium (SCM), two embryo rinsing protocols, and the use of conventional insemination instead of intracytoplasmic sperm injection (ICSI). METHODS: Results of two embryo rinsing methods (one-step vs sequential) and SCM collected on day 5 vs day 6 after retrieval were compared against trophectoderm (TE) biopsies as reference. Results from day 6 SCM in cycles fertilized by conventional insemination were compared with PGT-A using ICSI. RESULTS: The rate of concordance was higher in day 6 samples than in day 5 samples when the sequential method was used, in terms of total concordance (TC; day 6 vs day 5: 85.0% vs 60.0%, p = 0.0228), total concordance with same sex (TCS, 82.5% vs 28,0%, p < 0.0001), and full concordance with same sex (FCS, 62.5% vs 24.0%, p = 0.0025). The sequential method significantly out-performed the one-step method when SCM were collected on day 6 (sequential vs one-step, TC: 85.0% vs 64.5%, p = 0.0449; TCS: 82.5% vs 54.8%, p = 0.0113; FCS: 62.5% vs 25.8%, p = 0.0021). There was no significant difference in niPGT-A results between cycles fertilized by the conventional insemination and ICSI. CONCLUSION: We have shown a higher concordance rate when SCM was collected on day 6 and the embryos were rinsed in a sequential manner. Comparable results of niPGT-A when oocytes were fertilized by conventional insemination or ICSI. These optimization steps are important prior to commencement of a randomized trial in niPGT-A.


Asunto(s)
Fertilización In Vitro , Diagnóstico Preimplantación , Embarazo , Femenino , Masculino , Humanos , Diagnóstico Preimplantación/métodos , Semen , Pruebas Genéticas/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Aneuploidia , Blastocisto/patología
12.
Org Lett ; 26(14): 2697-2701, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37204455

RESUMEN

Tertiary C-F bonds are important structural designs; however, they suffer from challenging synthesis. Current methodologies use corrosive amine-HF salts or expensive and hazardous catalysts and reagents. Our group recently introduced collidinium tetrafluoroborate as an efficient fluorinating agent for anodic decarboxyfluorination reactions. Nevertheless, tertiary carboxylic acids are less readily available and more challenging to prepare than their alcohol analogues. Herein we report a practical, mild, and cheap electrochemical method to achieve deoxyfluorination of hindered carbon centers.

13.
Cell Mol Gastroenterol Hepatol ; 17(1): 93-106, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37743012

RESUMEN

Liver fibrosis of different etiologies is a serious health problem worldwide. There is no effective therapy available for liver fibrosis except the removal of the underlying cause of injury or liver transplantation. Development of liver fibrosis is caused by fibrogenic myofibroblasts that are not present in the normal liver, but rather activate from liver resident mesenchymal cells in response to chronic toxic or cholestatic injury. Many studies indicate that liver fibrosis is reversible when the causative agent is removed. Regression of liver fibrosis is associated with the disappearance of activated myofibroblasts and resorption of the fibrous scar. In this review, we discuss the results of genetic tracing and cell fate mapping of hepatic stellate cells and portal fibroblasts, their specific characteristics, and potential phenotypes. We summarize research progress in the understanding of the molecular mechanisms underlying the development and reversibility of liver fibrosis, including activation, apoptosis, and inactivation of myofibroblasts.


Asunto(s)
Cirrosis Hepática , Miofibroblastos , Humanos , Miofibroblastos/patología , Cirrosis Hepática/patología , Fibroblastos/patología , Hepatocitos
17.
Angew Chem Int Ed Engl ; 62(38): e202309563, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37540528

RESUMEN

Hydrogenation reactions are staple transformations commonly used across scientific fields to synthesise pharmaceuticals, natural products, and various functional materials. However, the vast majority of these reactions require the use of a toxic and costly catalyst leading to unpractical, hazardous and often functionally limited conditions. Herein, we report a new, general, practical, efficient, mild and high-yielding hydrogen-free electrochemical method for the reduction of alkene, alkyne, nitro and azido groups. Finally, this method has been applied to deuterium labelling.

18.
BMJ Open ; 13(7): e072557, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37500277

RESUMEN

INTRODUCTION: The success rate of in vitro fertilisation (IVF) treatment for couples with infertility remains low due to lack of a reliable tool in selecting euploid embryos for transfer. This study aims to compare the efficacy in embryo selection based on morphology alone compared with non-invasive preimplantation genetic testing for aneuploidy (niPGT-A) and morphology in infertile women undergoing IVF. METHODS AND ANALYSIS: This is a randomised double-blind controlled trial conducted in two tertiary assisted reproduction centres. A total of 500 infertile women will be recruited and undergo IVF as indicated. They will be randomly assigned on day 6 after oocyte retrieval into two groups: the intervention group using morphology and niPGT-A and the control group based on morphology alone. In the control group, blastocysts with the best quality morphology will be replaced first. In the intervention group, blastocysts with the best morphology and euploid result of spent culture medium will be replaced first. The primary outcome is a live birth per the first embryo transfer. The statistical analysis will be performed with the intention to treat and per protocol. ETHICS AND DISSEMINATION: Ethics approval was sought from the institutional review board of the two participating units. All participants will provide written informed consent before joining the study. The results of the study will be submitted to scientific conferences and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04474522.


Asunto(s)
Infertilidad Femenina , Embarazo , Humanos , Femenino , Fertilización In Vitro/métodos , Pruebas Genéticas/métodos , Aneuploidia , Transferencia de Embrión/métodos , Índice de Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
STAR Protoc ; 4(3): 102391, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37405925

RESUMEN

Here, we present a protocol for isolating human hepatocytes and neural progenitor cells from normal and nonalcoholic steatohepatitis livers. We describe steps for perfusion for scaled-up liver cell isolation and optimization of chemical digestion to achieve maximal yield and cell viability. We then detail a liver cell cryopreservation and potential applications, such as the use of human liver cells as a tool to link experimental and translational research.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Células Cultivadas , Hepatocitos , Separación Celular/métodos
20.
Int J Mol Epidemiol Genet ; 14(1): 11-18, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214589

RESUMEN

PURPOSE: Childhood cataracts and strabismus are among the most common causes of visual impairment in children worldwide, and prompt diagnosis and correction can significantly reduce disease burden. In certain regions, including the Eastern Caribbean, access to adequate treatment can be limited and epidemiological data scarce. This study aims to analyze the epidemiological data of pediatric strabismus and cataract cases in St. Vincent and the Grenadines. METHODS: The setting of the study is a clinical practice including 201 patients between the age of 0 to 19 who received care with World Pediatric Project (WPP). Factors analyzed include patient age, sex, and type of cataract or strabismus. The findings were compared to publicly available demographic information. RESULTS: The cases were divided into cataract (n=51), strabismus (n=134), and both strabismus and cataract (n=16). Mean ages (years) were 5.96, 5.54, and 4.50, respectively. The most frequent type of cataract and strabismus were congenital (n=25) and esotropia (n=95), respectively. The highest annual cumulative incidence was 31 and 49 cases per 100,000 people for cataracts and strabismus, respectively. CONCLUSION: This study provides regional epidemiological data on pediatric strabismus and cataracts. Further studies can expand the patient population by increasing collaboration with local providers. Ultimately, these findings can offer a basis for which additional epidemiological studies can be performed and help guide public health efforts to prevent visual impairment in St. Vincent and the Grenadines.

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