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1.
Plant J ; 110(3): 658-672, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35106853

RESUMEN

Plant cuticles are a mixture of crystalline and amorphous waxes that restrict the exchange of molecules between the plant and the atmosphere. The multicomponent nature of cuticular waxes complicates the study of the relationship between the physical and transport properties. Here, a model cuticle based on the epicuticular waxes of Petunia hybrida flower petals was formulated to test the effect of wax composition on diffusion of water and volatile organic compounds (VOCs). The model cuticle was composed of an n-tetracosane (C24 H50 ), 1-docosanol (C22 H45 OH), and 3-methylbutyl dodecanoate (C17 H34 O2 ), reflecting the relative chain length, functional groups, molecular arrangements, and crystallinity of the natural waxes. Molecular dynamics simulations were performed to obtain diffusion coefficients for compounds moving through waxes of varying composition. Simulated VOC diffusivities of the model system were found to highly correlate with in vitro measurements in isolated petunia cuticles. VOC diffusivity increased up to 30-fold in completely amorphous waxes, indicating a significant effect of crystallinity on cuticular permeability. The crystallinity of the waxes was highly dependent on the elongation of the lattice length and decrease in gap width between crystalline unit cells. Diffusion of water and higher molecular weight VOCs were significantly affected by alterations in crystalline spacing and lengths, whereas the low molecular weight VOCs were less affected. Comparison of measured diffusion coefficients from atomistic simulations and emissions from petunia flowers indicates that the role of the plant cuticle in the VOC emission network is attributed to the differential control on mass transfer of individual VOCs by controlling the composition, amount, and dynamics of scent emission.


Asunto(s)
Petunia , Compuestos Orgánicos Volátiles , Células Epidérmicas , Epidermis de la Planta/química , Hojas de la Planta/química , Compuestos Orgánicos Volátiles/análisis , Agua , Ceras/química
2.
Nat Chem Biol ; 17(2): 138-145, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33077978

RESUMEN

The plant cuticle is the final barrier for volatile organic compounds (VOCs) to cross for release to the atmosphere, yet its role in the emission process is poorly understood. Here, using a combination of reverse-genetic and chemical approaches, we demonstrate that the cuticle imposes substantial resistance to VOC mass transfer, acting as a sink/concentrator for VOCs and hence protecting cells from the potentially toxic internal accumulation of these hydrophobic compounds. Reduction in cuticle thickness has differential effects on individual VOCs depending on their volatility, and leads to their internal cellular redistribution, a shift in mass transfer resistance sources and altered VOC synthesis. These results reveal that the cuticle is not simply a passive diffusion barrier for VOCs to cross, but plays the aforementioned complex roles in the emission process as an integral member of the overall VOC network.


Asunto(s)
Flores/química , Petunia/química , Compuestos Orgánicos Volátiles/química , Regulación hacia Abajo , Genes de Plantas/genética , Fenilalanina/química , Interferencia de ARN , Solventes
3.
Am J Perinatol ; 40(14): 1573-1578, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-34784616

RESUMEN

OBJECTIVE: The objective of our study is to determine if human immunodeficiency virus (HIV)-positive pregnant patients have a higher rate of group B streptococcus (GBS) rectovaginal colonization compared with HIV-negative pregnant patients. STUDY DESIGN: Our study is a multi-site retrospective study performed at Ochsner Louisiana State University-Health Shreveport and Monroe campuses including patients who delivered between December 2011and June 2019. Rates of GBS rectovaginal colonization between HIV-positive pregnant patients were compared with a control group of HIV-negative patients. The control group was age and race matched in a 2:1 fashion. The primary outcome was to investigate rates of GBS rectovaginal colonization. Secondary outcomes included GBS culture antibiotic sensitivities, presence of GBS urinary tract infection, GBS positivity based on HIV viral load, and GBS positivity based on new vs established diagnosis of HIV. Continuous data were analyzed using an unpaired t-test, and categorical data were analyzed using a Chi-squared test. The probability level of <0.05 was set as statistically significant. RESULTS: A total of 225 patients were included in the final analysis, 75 HIV-positive and 150 HIV-negative controls. Demographic differences were noted. HIV-positive patients were more likely to deliver preterm and were more likely to deliver via cesarean section. Our primary outcome showed no significant differences in incidence of GBS colonization between HIV-positive patients and control group (n = 31, 41.3% vs n = 46, 30.6%, p = 0.136). Antibiotic resistance patterns showed no significant difference between the two groups. There were no significant differences in GBS positivity based on HIV viral load. CONCLUSION: Our study does not show a statistically significant difference in the incidence of GBS colonization between HIV-positive patients and HIV-negative controls. KEY POINTS: · HIV-positive pregnant patients do not have an increased risk of GBS rectovaginal colonization.. · HIV-positive pregnant patients have similar rates of GBS colonization regardless of viral load.. · GBS antibiotic sensitivities are similar in HIV-positive and HIV-negative pregnant patients..


Asunto(s)
Infecciones por VIH , Complicaciones Infecciosas del Embarazo , Infecciones Estreptocócicas , Recién Nacido , Embarazo , Humanos , Femenino , Complicaciones Infecciosas del Embarazo/diagnóstico , Estudios Retrospectivos , Cesárea , Antibacterianos/uso terapéutico , Streptococcus agalactiae , Infecciones Estreptocócicas/complicaciones , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/epidemiología , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Vagina
4.
Plant J ; 108(3): 737-751, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34403557

RESUMEN

Out of the three aromatic amino acids, the highest flux in plants is directed towards phenylalanine, which is utilized to synthesize proteins and thousands of phenolic metabolites contributing to plant fitness. Phenylalanine is produced predominantly in plastids via the shikimate pathway and subsequent arogenate pathway, both of which are subject to complex transcriptional and post-transcriptional regulation. Previously, it was shown that allosteric feedback inhibition of arogenate dehydratase (ADT), which catalyzes the final step of the arogenate pathway, restricts flux through phenylalanine biosynthesis. Here, we show that in petunia (Petunia hybrida) flowers, which typically produce high phenylalanine levels, ADT regulation is relaxed, but not eliminated. Moderate expression of a feedback-insensitive ADT increased flux towards phenylalanine, while high overexpression paradoxically reduced phenylalanine formation. This reduction could be partially, but not fully, recovered by bypassing other known metabolic flux control points in the aromatic amino acid network. Using comparative transcriptomics, reverse genetics, and metabolic flux analysis, we discovered that transcriptional regulation of the d-ribulose-5-phosphate 3-epimerase gene in the pentose phosphate pathway controls flux into the shikimate pathway. Taken together, our findings reveal that regulation within and upstream of the shikimate pathway shares control over phenylalanine biosynthesis in the plant cell.


Asunto(s)
Hidroliasas/genética , Petunia/genética , Petunia/metabolismo , Fenilalanina/biosíntesis , Proteínas de Plantas/genética , Carbohidrato Epimerasas/genética , Carbohidrato Epimerasas/metabolismo , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Hidroliasas/metabolismo , Mutación , Fenilalanina/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Plastidios/genética , Plastidios/metabolismo , Metabolismo Secundario/genética , Ácido Shikímico/metabolismo
5.
Nat Chem Biol ; 16(8): 850-856, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32284603

RESUMEN

In plants, phenylalanine biosynthesis occurs via two compartmentally separated pathways. Overexpression of petunia chorismate mutase 2 (PhCM2), which catalyzes the committed step of the cytosolic pathway, increased flux in cytosolic phenylalanine biosynthesis, but paradoxically decreased the overall levels of phenylalanine and phenylalanine-derived volatiles. Concomitantly, the levels of auxins, including indole-3-acetic acid and its precursor indole-3-pyruvic acid, were elevated. Biochemical and genetic analyses revealed the existence of metabolic crosstalk between the cytosolic phenylalanine biosynthesis and tryptophan-dependent auxin biosynthesis mediated by an aminotransferase that uses a cytosolic phenylalanine biosynthetic pathway intermediate, phenylpyruvate, as an amino acceptor for auxin formation.


Asunto(s)
Ácidos Indolacéticos/química , Ácidos Indolacéticos/metabolismo , Fenilalanina/biosíntesis , Vías Biosintéticas/genética , Citosol/metabolismo , Indoles , Fenilalanina/metabolismo , Ácidos Fenilpirúvicos/metabolismo , Plantas/metabolismo , Triptófano
6.
J Cell Physiol ; 236(3): 1866-1874, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32700783

RESUMEN

Adverse intrauterine environment has been considered a predisposing factor for fetal programming in preeclampsia. Using human umbilical vein endothelial cells (HUVECs), we specifically explored if aberrant histone methylation occurs in fetal endothelial cells in preeclampsia. Strikingly, we found that increased di-, and tri-methylation of histone H3 lysine 9 (H3K9me2 and H3K9me3) expression were associated with upregulation of methyltransferase G9a and downregulation of endothelial nitric oxide synthase and CuZn-SOD expression in preeclamptic HUVECs. We further demonstrated that hypoxia-induced hypermethylation of H3K9 and reduced CuZn-SOD expression mimicked what were seen in preeclamptic HUVECs and inhibition of G9a could attenuate these hypoxia-induced adverse events. Our study was the first to identify hypermethylation status in fetal endothelial cells in preeclampsia, which provides plausible evidence that increased oxidative stress in the intrauterine environment is likely a mechanism to induce aberrant histone modification in fetal endothelial cells which may have a significant impact on fetal programming in preeclampsia.


Asunto(s)
Células Endoteliales/metabolismo , Células Endoteliales/patología , Feto/patología , Histonas/metabolismo , Lisina/metabolismo , Preeclampsia/metabolismo , Regulación hacia Arriba , Adulto , Hipoxia de la Célula , Regulación hacia Abajo , Femenino , Antígenos de Histocompatibilidad/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Metilación , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo , Placenta/metabolismo , Embarazo , Superóxido Dismutasa/metabolismo
7.
Nat Chem Biol ; 15(6): 583-588, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31101916

RESUMEN

Plants synthesize volatile organic compounds (VOCs) to attract pollinators and beneficial microorganisms, to defend themselves against herbivores and pathogens, and for plant-plant communication. In general, VOCs accumulate in and are emitted from the tissue of their biosynthesis. However, using biochemical and reverse genetic approaches, we demonstrate a new physiological phenomenon: inter-organ aerial transport of VOCs via natural fumigation. Before petunia flowers open, a tube-specific terpene synthase produces sesquiterpenes, which are released inside the buds and then accumulate in the stigma, potentially defending the developing stigma from pathogens. These VOCs also affect reproductive organ development and seed yield, which are previously unknown functions of terpenoid compounds.


Asunto(s)
Flores/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Flores/química , Estructura Molecular , Compuestos Orgánicos Volátiles/química
8.
Metab Eng ; 56: 77-84, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31470115

RESUMEN

Photosynthetic microorganisms are increasingly being investigated as a sustainable alternative to existing bio-industrial processes, converting CO2 into desirable end products without the use of carbohydrate feedstock. The Calvin-Benson-Bassham (CBB) cycle is the main pathway of carbon fixation metabolism in photosynthetic organisms. In this study, we analyzed the metabolic fluxes in two strains of the unicellular cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis) that overexpressed fructose-1,6/sedoheptulose-1,7-bisphosphatase (FBP/SBPase) and transketolase (TK), respectively. These two potential carbon flux control enzymes in the CBB cycle had previously been shown to improve biomass accumulation when overexpressed under air and low light (15 µmol m-2 s-1) conditions (Liang and Lindblad, 2016). We measured the growth rates of Synechocystis under atmospheric and high (3% v/v) CO2 conditions at 80 µmol m-2 s-1. Surprisingly, the cells overexpressing transketolase (tktA) demonstrated no significant increase in growth rates when CO2 was increased, suggesting an altered carbon flux distribution and a potential metabolic bottleneck in carbon fixation. Moreover, the tktA strain had an increased susceptibility to oxidative stress under high light as revealed by its chlorotic phenotype under high light conditions. In contrast, the fructose-1,6/sedoheptulose-1,7-bisphosphatase (70glpX) and wild-type cells demonstrated increases in growth rates as expected. To investigate the disparate phenotypical responses of these different Synechocystis strains, isotopically non-stationary metabolic flux analysis (INST-MFA) was used to estimate the carbon flux distribution of tktA, 70glpX, and a kanamycin-resistant control (Km), under atmospheric conditions. In addition, untargeted label-free proteomics, which can detect changes in relative enzymatic abundance, was employed to study the possible effects caused by overexpressing each enzyme. Fluxomic and proteomic results indicated a decrease in oxidative pentose phosphate pathway activity when either FBP/SBPase or TK were overexpressed, resulting in increased carbon fixation efficiency. These results are an example of the integration of multiple omic-level experimental techniques and can be used to guide future metabolic engineering efforts to improve performances and efficiencies.


Asunto(s)
Biomasa , Análisis de Flujos Metabólicos , Vía de Pentosa Fosfato/fisiología , Fotosíntesis/fisiología , Synechocystis/metabolismo , Proteómica , Synechocystis/genética
9.
Metab Eng ; 49: 36-46, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30025763

RESUMEN

Lignin is a polymer that significantly inhibits saccharification of plant feedstocks. Adjusting the composition or reducing the total lignin content have both been demonstrated to result in an increase in sugar yield from biomass. However, because lignin is essential for plant growth, it cannot be manipulated with impunity. Thus, it is important to understand the control of carbon flux towards lignin biosynthesis such that optimal modifications to it can be made precisely. Phenylalanine (Phe) is the common precursor for all lignin subunits and it is commonly accepted that all biosynthetic steps, spanning multiple subcellular compartments, are known, yet an in vivo model of how flux towards lignin is controlled is lacking. To address this deficiency, we formulated and parameterized a kinetic model based on data from feeding Arabidopsis thaliana basal lignifying stems with ring labeled [13C6]-Phe. Several candidate models were compared by an information theoretic approach to select the one that best matched the experimental observations. Here we present a dynamic model of phenylpropanoid metabolism across several subcellular compartments that describes the allocation of carbon towards lignin biosynthesis in wild-type Arabidopsis stems. Flux control coefficients for the enzymes in the pathway starting from arogenate dehydratase through 4-coumarate: CoA ligase were calculated and show that the plastidial cationic amino-acid transporter has the highest impact on flux.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Lignina/biosíntesis , Modelos Biológicos , Fenilpropionatos/metabolismo , Tallos de la Planta , Arabidopsis/citología , Arabidopsis/metabolismo , Tallos de la Planta/citología , Tallos de la Planta/metabolismo
11.
Phytochem Anal ; 28(4): 267-276, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28146307

RESUMEN

INTRODUCTION: The phenylpropanoid pathway is a source of a diverse group of compounds derived from phenylalanine, many of which are involved in lignin biosynthesis and serve as precursors for the production of valuable compounds, such as coumarins, flavonoids, and lignans. Consequently, recent efforts have been invested in mechanistically understanding monolignol biosynthesis, making the quantification of these metabolites vital. OBJECTIVE: To develop an improved and comprehensive analytical method for (i) extensively profiling, and (ii) accurately quantifiying intermediates of the monolignol biosynthetic network, using Arabidopsis thaliana as a model system. METHOD: A liquid chromatography-tandem mass spectrometry with electrospray ionization was developed to quantify phenylpropanoid metabolites in Arabidopsis wildtype and cinnamoyl CoA reductase1 (CCR1) deficient lines (ccr1). RESULTS: Vortexing at high temperatures (65°C) enhanced release of phenylpropanoids, specifically the more hydrophobic compounds. A pH of 5.3 and ammonium acetate buffer concentration of 2.5 mM resulted in an optimal analyte response across standards. Ion suppression was estimated using standard spike recovery studies for accurate quantitation. The optimized method was used to profile Arabidopsis wildtype and ccr1 stems. An increase in hydroxycinnamic acid derivatives and a decrease in the hydroxycinnamyl aldehydes and alcohols in ccr1 lines, supports a shift of flux from lignin synthesis to other secondary metabolites and phenylpropanoid derivatives. CONCLUSIONS: Compared to existing targeted profiling techniques, our method is capable of quantifying a wider range of intermediates (15 out of 22 in WT Arabidopsis stems) at low in vivo concentrations (~50 pmol/g-FW for certain compounds), while requiring minimal sample preparation. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Arabidopsis/metabolismo , Metabolómica , Fenilalanina/metabolismo , Propanoles/metabolismo , Aldehído Oxidorreductasas , Cromatografía de Fase Inversa , Ácidos Cumáricos/metabolismo , Lignina , Espectrometría de Masas en Tándem
12.
Development ; 138(14): 3033-42, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21693519

RESUMEN

Components of the planar cell polarity (PCP) pathway are required for the caudal tangential migration of facial branchiomotor (FBM) neurons, but how PCP signaling regulates this migration is not understood. In a forward genetic screen, we identified a new gene, nhsl1b, required for FBM neuron migration. nhsl1b encodes a WAVE-homology domain-containing protein related to human Nance-Horan syndrome (NHS) protein and Drosophila GUK-holder (Gukh), which have been shown to interact with components of the WAVE regulatory complex that controls cytoskeletal dynamics and with the polarity protein Scribble, respectively. Nhsl1b localizes to FBM neuron membrane protrusions and interacts physically and genetically with Scrib to control FBM neuron migration. Using chimeric analysis, we show that FBM neurons have two modes of migration: one involving interactions between the neurons and their planar-polarized environment, and an alternative, collective mode involving interactions between the neurons themselves. We demonstrate that the first mode of migration requires the cell-autonomous functions of Nhsl1b and the PCP components Scrib and Vangl2 in addition to the non-autonomous functions of Scrib and Vangl2, which serve to polarize the epithelial cells in the environment of the migrating neurons. These results define a role for Nhsl1b as a neuronal effector of PCP signaling and indicate that proper FBM neuron migration is directly controlled by PCP signaling between the epithelium and the migrating neurons.


Asunto(s)
Movimiento Celular/fisiología , Nervio Facial/citología , Proteínas de la Membrana/metabolismo , Neuronas/fisiología , Transducción de Señal/fisiología , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Animales , Animales Modificados Genéticamente , Células Cultivadas , Inmunohistoquímica , Inmunoprecipitación , Hibridación in Situ , Mutagénesis , Plásmidos/genética
13.
New Phytol ; 204(3): 661-670, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24985707

RESUMEN

Volatile phenylpropenes play important roles in the mediation of interactions between plants and their biotic environments. Their biosynthesis involves the elimination of the oxygen functionality at the side-chain of monolignols and competes with lignin formation for monolignol utilization. We hypothesized that biochemical steps before the monolignol branch point are shared between phenylpropene and lignin biosynthesis; however, genetic evidence for this shared pathway has been missing until now. Our hypothesis was tested by RNAi suppression of the petunia (Petunia hybrida) cinnamoyl-CoA reductase 1 (PhCCR1), which catalyzes the first committed step in monolignol biosynthesis. Detailed metabolic profiling and isotopic labeling experiments were performed in petunia transgenic lines. Downregulation of PhCCR1 resulted in reduced amounts of total lignin and decreased flux towards phenylpropenes, whereas internal and emitted pools of phenylpropenes remained unaffected. Surprisingly, PhCCR1 silencing increased fluxes through the general phenylpropanoid pathway by upregulating the expression of cinnamate-4-hydroxylase (C4H), which catalyzes the second reaction in the phenylpropanoid pathway. In conclusion, our results show that PhCCR1 is involved in both the biosynthesis of phenylpropenes and lignin production. However, PhCCR1 does not perform a rate-limiting step in the biosynthesis of phenylpropenes, suggesting that scent biosynthesis is prioritized over lignin formation in petals.


Asunto(s)
Flores/metabolismo , Petunia/metabolismo , Propanoles/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Silenciador del Gen , Estructura Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Propanoles/química , Transporte de Proteínas , Interferencia de ARN , Compuestos Orgánicos Volátiles/química
14.
Obstet Gynecol ; 142(6): 1450-1453, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37708501

RESUMEN

Our retrospective cohort study evaluates the diagnostic yield of weekly laboratory surveillance in outpatient management of hypertensive disorders of pregnancy (HDP) based on patient clinical status at the time of laboratory testing. The study included 459 patients and 1,082 laboratory episodes: 356 (32.9%) episodes were performed in the setting of concerning clinical findings and 726 (67.1%) when the patient was asymptomatic. Overall, the diagnostic yield for abnormal laboratory values (n=11) was 1.0% (95% CI 0.4-1.6%) of all assessments performed and 2.4% (95% CI 1.0-3.8%) among all patients in the cohort. The prevalence of abnormal test results was higher in patients with clinical findings (2.8%, 95% CI 1.1-4.5%) compared with those who were asymptomatic (0.1%, 95% CI 0-0.2%) ( P <.01). Clinical findings suggestive of worsening disease had a 91% sensitivity (95% CI 59-100%) and a 99% (95% CI 99-100%) negative predictive value for abnormal laboratory values. Directed screening based on signs and symptoms, rather than universal weekly screening, may be a potential strategy to lower costs and reduce multiple blood draws for patients with HDP, because there is a low diagnostic yield for this practice.


Asunto(s)
Hipertensión Inducida en el Embarazo , Femenino , Humanos , Embarazo , Hipertensión Inducida en el Embarazo/diagnóstico , Hipertensión Inducida en el Embarazo/terapia , Hipertensión Inducida en el Embarazo/epidemiología , Laboratorios , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Espera Vigilante , Complicaciones Cardiovasculares del Embarazo
15.
Nat Commun ; 14(1): 330, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658137

RESUMEN

For volatile organic compounds (VOCs) to be released from the plant cell into the atmosphere, they have to cross the plasma membrane, the cell wall, and the cuticle. However, how these hydrophobic compounds cross the hydrophilic cell wall is largely unknown. Using biochemical and reverse-genetic approaches combined with mathematical simulation, we show that cell-wall localized non-specific lipid transfer proteins (nsLTPs) facilitate VOC emission. Out of three highly expressed nsLTPs in petunia petals, which emit high levels of phenylpropanoid/benzenoid compounds, only PhnsLTP3 contributes to the VOC export across the cell wall to the cuticle. A decrease in PhnsLTP3 expression reduces volatile emission and leads to VOC redistribution with less VOCs reaching the cuticle without affecting their total pools. This intracellular build-up of VOCs lowers their biosynthesis by feedback downregulation of phenylalanine precursor supply to prevent self-intoxication. Overall, these results demonstrate that nsLTPs are intrinsic members of the VOC emission network, which facilitate VOC diffusion across the cell wall.


Asunto(s)
Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/metabolismo , Difusión , Fenilalanina , Pared Celular/metabolismo , Lípidos
16.
Obstet Gynecol ; 141(3): 555-562, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36735413

RESUMEN

OBJECTIVE: To compare frequency of perinatal death between pregnant patients who completed the mRNA coronavirus disease 2019 (COVID-19) vaccination series and unvaccinated patients. METHODS: This retrospective cohort study included 15,865 pregnant patients who delivered 16,132 newborns after 20 weeks of gestation within a large regional health system between January 1, 2021, and December 31, 2021. Patients who received two doses of mRNA vaccine (Pfizer-BioNTech [BNT162b2] or Moderna [mRNA-1273]) were included in the vaccinated group and were compared with unvaccinated patients. Exclusions included partial vaccination, viral-vector vaccine, major congenital anomalies, and higher-order multiple gestation. Our primary outcome was perinatal death, including stillbirth and neonatal death, which was evaluated by logistic regression. Unadjusted odds ratios and adjusted odds ratios (aORs) were reported, controlling for age, body mass index (BMI), diabetes, hypertension, smoking, twin gestation, and insurance status. Propensity score matching was also performed. RESULTS: A total of 15,865 patients were included in the final analysis: 2,069 in the vaccination group and 13,796 in the control group. Only 13.0% of the cohort was included in the vaccination group; however, the vaccination rate increased over the course of the study period as the vaccine became more widely available and accepted. Vaccinated patients were older, with higher rates of people of non-Black racial non-Hispanic ethnic backgrounds, people with private insurance, and those with higher BMIs. Vaccination was associated with a lower incidence of perinatal death (0.5% vaccinated group vs 0.8% unvaccinated group, aOR 0.20 0.05-0.88). Vaccination against COVID-19 was also associated with lower rates of preterm delivery (aOR 0.63, 0.48-0.82), neonates with very low birth weight (aOR 0.35, 0.15-0.84), and neonatal intensive care unit (NICU) admission (aOR 0.66, 0.52-0.85). The association between vaccination and lower rates of perinatal death was no longer significant after propensity score matching. CONCLUSION: In a large retrospective cohort study, receipt of the primary mRNA COVID-19 vaccination series was associated with a lower rate of several adverse pregnancy outcomes, including perinatal death, preterm delivery, neonates with very low birth weight, and NICU admission. Although the decreased rates of perinatal death did not remain significant after propensity score matching, there was evidence of directional benefit for vaccinated patients.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Muerte Perinatal , Nacimiento Prematuro , Femenino , Humanos , Recién Nacido , Embarazo , Vacuna BNT162 , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/complicaciones , Vacunas contra la COVID-19/efectos adversos , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Estudios Retrospectivos , Vacunación/efectos adversos
17.
J Exp Bot ; 63(6): 2293-308, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22371075

RESUMEN

For the past decade, flux maps have provided researchers with an in-depth perspective on plant metabolism. As a rapidly developing field, significant headway has been made recently in computation, experimentation, and overall understanding of metabolic flux analysis. These advances are particularly applicable to the study of plant metabolism. New dynamic computational methods such as non-stationary metabolic flux analysis are finding their place in the toolbox of metabolic engineering, allowing more organisms to be studied and decreasing the time necessary for experimentation, thereby opening new avenues by which to explore the vast diversity of plant metabolism. Also, improved methods of metabolite detection and measurement have been developed, enabling increasingly greater resolution of flux measurements and the analysis of a greater number of the multitude of plant metabolic pathways. Methods to deconvolute organelle-specific metabolism are employed with increasing effectiveness, elucidating the compartmental specificity inherent in plant metabolism. Advances in metabolite measurements have also enabled new types of experiments, such as the calculation of metabolic fluxes based on (13)CO(2) dynamic labelling data, and will continue to direct plant metabolic engineering. Newly calculated metabolic flux maps reveal surprising and useful information about plant metabolism, guiding future genetic engineering of crops to higher yields. Due to the significant level of complexity in plants, these methods in combination with other systems biology measurements are necessary to guide plant metabolic engineering in the future.


Asunto(s)
Dióxido de Carbono/metabolismo , Marcaje Isotópico/métodos , Redes y Vías Metabólicas , Plantas/metabolismo , Isótopos de Carbono/análisis , Compartimento Celular , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Modelos Biológicos
18.
J Matern Fetal Neonatal Med ; 35(12): 2260-2265, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32576066

RESUMEN

OBJECTIVE: It was reported that fetal gender was associated with gestational-age related incidence of preeclampsia. However, there is no study to date to evaluate the association of fetal gender differences with all hypertensive disorders of pregnancy. The present study aimed to evaluate the association, if any, between fetal gender differences and the disposition to develop hypertensive disorders of pregnancy and the risk of developing severe features. METHODS: This was a single site retrospective cohort that included patients who were diagnosed with either gestational hypertension, preeclampsia without severe features, severe preeclampsia, superimposed preeclampsia, or superimposed preeclampsia with severe features. Patients were divided into two groups based on male versus female fetal gender. Our primary outcome was gestational age (GA) at diagnosis of hypertensive disorder. GA ranges evaluated were <28 weeks, 28-34 weeks, 34-37 weeks, and >37 weeks. Secondary outcomes were maternal morbidity (severe features at delivery, HELLP syndrome, placental abruption, eclampsia, maternal death, and maternal intensive care unit (ICU) admission), GA range at delivery, indication for delivery, and fetal outcomes. Continuous data were analyzed using an unpaired t-test and categorical data was analyzed using Chi-square test. A probability level was <.05 was set as statistically significant. RESULTS: A total of 597 patients were included, 275 with male fetus and 322 with female fetus. Demographic comparison between the two groups showed similar rates in patients complicated with chronic hypertension, but a higher incidence of antihypertensive medication used in the male fetus group, p < .05. All other demographics were similar between the two groups. There were no significant differences in maternal primary and secondary outcomes, including GA range at diagnosis and severe features at delivery, and fetal outcomes, including neonatal intensive care unit (NICU) admission, evaluated between the two groups. CONCLUSION: Our study did not find significant differences between fetal gender and GA at the diagnosis of hypertensive disorders of pregnancy or development of severe features in the study subjects.


Asunto(s)
Eclampsia , Hipertensión Inducida en el Embarazo , Preeclampsia , Femenino , Humanos , Hipertensión Inducida en el Embarazo/epidemiología , Recién Nacido , Masculino , Placenta , Preeclampsia/diagnóstico , Preeclampsia/epidemiología , Embarazo , Estudios Retrospectivos
19.
J Steroid Biochem Mol Biol ; 222: 106155, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35868598

RESUMEN

Vitamin D deficiency is a widespread health problem globally and vitamin D deficiency/ insufficiency in pregnancy is a risk factor for preeclampsia, a hypertensive disorder in human pregnancy. Vitamin D elicits its biological effects through binding to its receptor VDR. In the present study, we determined maternal vascular expression of VDR and hnRNPC1/C2, a native repressor of VDR, in subcutaneous adipose tissue from women with normal pregnancy and preeclampsia. Maternal antenatal and postnatal vitamin D levels were measured. We found that hnRNPC1/C2 expression was markedly increased, while VDR expression was markedly reduced, in maternal vessel endothelium and smooth muscle cells from women with preeclampsia compared to that from normal pregnant controls. Reduced VDR expression was relevant to low maternal antenatal and postnatal vitamin D levels in women with preeclampsia. Using human umbilical vein endothelial cells (HUVECs) as an endothelial model, we further investigated the role of hnRNPC1/C2-mediated VDR expression in endothelial cells, and tested effect of hnRNPC1/C2 inhibition on endothelial response to bioactive vitamin D, 1,25(OH)2D3. Our results showed that inhibition of hnRNPC1/C2 by hnRNPC1/C2 siRNA resulted in not only an increase in endothelial VDR expression, but further improved endothelial response to 1,25(OH)2D3. These findings indicate that aberrant hnRNPC1/C2 expression may contribute to reduced vascular expression of VDR in women with preeclampsia and suggest that hnRNPC1/C2 could be a target for improving vascular endothelial cell response to vitamin D.


Asunto(s)
Preeclampsia , Deficiencia de Vitamina D , Endotelio Vascular/metabolismo , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Preeclampsia/genética , Preeclampsia/metabolismo , Embarazo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Vitamina D/metabolismo , Vitaminas
20.
J Matern Fetal Neonatal Med ; 35(19): 3694-3699, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33092413

RESUMEN

OBJECTIVE: To investigate differences in maternal and fetal outcomes among pregnant patients with chronic hypertension requiring antihypertensives for adequate control versus those who do not require antihypertensives. STUDY DESIGN: Single-site retrospective cohort study including pregnant patients with chronic hypertension from 2015-2018. Two groups included those who required antihypertensives versus those who did not. Primary outcome is composite morbidity: pregnancy loss after 20 weeks, IUGR, maternal death, maternal stroke or TIA, pulmonary edema, renal failure, hypertensive emergency, HELLP syndrome, placental abruption or delivery before 34 weeks. Secondary outcomes included development of severe features, indication for preterm labor less than 37 weeks, incidence of severe range blood pressures, and neonatal outcomes. Student t, chi square, and Kruskal-Wallis tests where appropriate. Logistic regression used to account for potential confounders. RESULTS: Study cohort included 117 on antihypertensives and 114 not on antihypertensives. Use of antihypertensives was associated with the composite primary outcome (Odds ratio [OR], 3.88; 95% confidence interval [CI], 1.66-9.78). Use of antihypertensive medications was also associated with increased risk of prenatal diagnosis of IUGR, delivery prior to 34 weeks, development of severe features, severe blood pressure during pregnancy, earlier mean gestational age at delivery, lower mean birth weight, and higher risk of NICU admission. Logistic regression analysis showed that the association between medication requirement and our composite primary outcome persisted even after adjustment for age, BMI, and presence of gestational diabetes. CONCLUSION: Our findings show an association between the requirement of antihypertensive medication use a significantly higher risk of composite primary outcome, prenatal diagnosis of IUGR, delivery prior to 34 weeks, and the development of severe features.


Asunto(s)
Antihipertensivos , Hipertensión , Antihipertensivos/uso terapéutico , Femenino , Edad Gestacional , Humanos , Recién Nacido , Placenta , Embarazo , Estudios Retrospectivos
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