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1.
Fertil Steril ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38986758

RESUMEN

OBJECTIVE: To examine trends, characteristics, and outcomes of donor oocyte embryo transfer cycles by original oocyte and resultant embryo state and determine whether oocyte state (fresh or frozen) is differentially associated with clinical pregnancy, live birth, and term, healthy birthweight neonates among singleton live births. DESIGN: Retrospective cohort study. SETTING: National study. PATIENT(S): Patients undergoing donor oocyte embryo transfer cycles in the United States reporting to the National Assisted Reproductive Technology Surveillance System from 2013 to 2020. INTERVENTION(S): Original donor oocyte and resultant embryo state (fresh or frozen). MAIN OUTCOME MEASURE(S): Annual numbers and proportions of total donor oocyte embryo transfer cycles stratified by oocyte and embryo state and single embryo transfer cycles resulting in the live birth of term (≥37 weeks gestation), healthy birthweight (≥2,500 g) singletons during 2013-2020. Rates of live birth and term, healthy birthweight neonates among singleton live births for 2018-2020 are also reported. Relative risks examine associations between donor oocyte state and live birth and term, healthy birthweight neonates among singleton live births resulting from donor oocyte embryo transfer cycles. RESULT(S): From 2013 to 2020, there were 135,085 donor oocyte embryo transfer cycles, of which the proportions increased for frozen embryos (42.3%-76.6%), fresh embryos using frozen donor oocytes (19.9%-68.3%) and single embryo transfers (36.4%-85.5%). During 2018-2020, there were 48,679 donor oocyte embryo transfer cycles. Rates of live birth were lower with frozen compared with fresh donor oocytes for both fresh (46.2%, 55.9%; adjusted relative risk [aRR], 0.83; 95% confidence interval [CI], 0.79-0.87) and frozen (41.3%, 45.8%; aRR, 0.94; 95% CI, 0.91-0.98) embryo transfer cycles. Among singleton live births, rates of delivering a term, healthy birth weight neonate were similar for frozen compared with fresh donor oocyte transfer cycles among fresh (77.3, 77.2%; aRR, 1.01; 95% CI, 0.98-1.03) and frozen (75.6, 75.1%; aRR, 1.02; 95% CI, 0.99-1.04) embryos. CONCLUSION(S): In this national study of donor oocyte embryo transfer cycles, frozen embryo transfers, fresh embryo transfers using frozen oocytes, and single embryo transfers increased. Although frozen compared with fresh oocytes were associated with a slightly reduced rate of live birth, rates of term, healthy birthweight neonates among singleton live births were comparable between donor oocyte states.

2.
Womens Health Rep (New Rochelle) ; 4(1): 288-297, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37363358

RESUMEN

Objective: To estimate uptake of influenza, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap), and COVID-19 vaccines during pregnancy and describe vaccine attitudes and beliefs among predominantly racial and ethnic minority individuals delivering at a publicly funded hospital. Methods: We collected survey and electronic medical record data for English-speaking postpartum individuals who delivered a live-born infant from July 7, 2022, through August 21, 2022, and agreed to participate in our study. The 58-item survey included questions about general vaccine attitudes and beliefs as well as vaccine-specific questions. We calculated rates of influenza, Tdap, and COVID-19 vaccinations and compared distributions of survey responses by number (no vaccines, one vaccine, or two or three of the recommended vaccines) and type of vaccines received during pregnancy. Results: Of the 231 eligible individuals, 125 (54.1%) agreed to participate. Rates of influenza, Tdap, and COVID-19 vaccination were 18.4%, 48.0%, and 5.6% respectively. A total of 61 (48.8%) did not receive any recommended vaccines during pregnancy, 40 (32.0%) received one vaccine, and 24 (19.0%) received two or three vaccines. Approximately 66.1% of the no vaccine group, 81.6% of the one vaccine group, and 87.5% of the two or three vaccine group strongly agreed or agreed that they trusted the vaccine information provided by their obstetrician or midwife. While most (>69.2%) agreed that the vaccine-preventable diseases were dangerous for pregnant women, only 24.0%, 29.3%, and 40.3% agreed that they were worried about getting influenza, whooping cough, or COVID-19, respectively, while pregnant. Discussion: Vaccine uptake in our population was low and may be due, in part, to low perceived susceptibility to vaccine-preventable diseases. Obstetricians and midwives were trusted sources of vaccine information, suggesting that enhanced communication strategies could be critical for addressing maternal vaccine hesitancy, particularly in communities of color justifiably affected by medical mistrust.

3.
Curr Opin Pediatr ; 32(4): 601-609, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32692056

RESUMEN

PURPOSE OF REVIEW: To offer healthcare providers current, evidence-based approaches for addressing vaccine hesitancy to increase vaccine coverage and reduce the frequency of vaccine-preventable disease outbreaks. RECENT FINDINGS: Vaccine hesitancy is a growing problem with profound societal, economic, and medical consequences. Understanding the complexity of vaccine hesitancy can inform approaches to increasing vaccine uptake on both the individual and population levels. Notably, pediatricians play a critical role in increasing vaccine uptake due to their relationships with families. This doctor-patient relationship establishes trust and allows evidence-based intervention strategies to be effective in the office. Understanding potential solutions outside the office, such as media campaigns and policy changes, also provide insight into vaccine hesitancy and potential directions for future research. While pediatricians' attempts in the clinic to increase coverage remain crucial, vaccine hesitancy remains a formidable public health problem that requires attention on both the micro and macro levels to be addressed successfully. SUMMARY: Providers have an opportunity to increase both confidence in and uptake of vaccines. Public health interventions would effectively complement strategies in the clinic to increase overall coverage.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de Salud/psicología , Relaciones Médico-Paciente , Vacunación/psicología , Vacunas/administración & dosificación , Personal de Salud , Humanos , Entrevista Motivacional
4.
Insect Biochem Mol Biol ; 59: 58-71, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25701385

RESUMEN

Members of the multicopper oxidase (MCO) family of enzymes can be classified by their substrate specificity; for example, ferroxidases oxidize ferrous iron, ascorbate oxidases oxidize ascorbate, and laccases oxidize aromatic substrates such as diphenols. Our previous work on an insect multicopper oxidase, MCO1, suggested that it may function as a ferroxidase. This hypothesis was based on three lines of evidence: RNAi-mediated knock down of Drosophila melanogaster MCO1 (DmMCO1) affects iron homeostasis, DmMCO1 has ferroxidase activity, and DmMCO1 has predicted iron binding residues. In our current study, we expanded our focus to include MCO1 from Anopheles gambiae, Tribolium castaneum, and Manduca sexta. We verified that MCO1 orthologs have similar expression profiles, and that the MCO1 protein is located on the basal surface of cells where it is positioned to oxidize substrates in the hemolymph. In addition, we determined that RNAi-mediated knock down of MCO1 in A. gambiae affects iron homeostasis. To further characterize the enzymatic activity of MCO1 orthologs, we purified recombinant MCO1 from all four insect species and performed kinetic analyses using ferrous iron, ascorbate and two diphenols as substrates. We found that all of the MCO1 orthologs are much better at oxidizing ascorbate than they are at oxidizing ferrous iron or diphenols. This result is surprising because ascorbate oxidases are thought to be specific to plants and fungi. An analysis of three predicted iron binding residues in DmMCO1 revealed that they are not required for ferroxidase or laccase activity, but two of the residues (His374 and Asp380) influence oxidation of ascorbate. These two residues are conserved in MCO1 orthologs from insects and crustaceans; therefore, they are likely to be important for MCO1 function. The results of this study suggest that MCO1 orthologs function as ascorbate oxidases and influence iron homeostasis through an unknown mechanism.


Asunto(s)
Anopheles/enzimología , Ascorbato Oxidasa/metabolismo , Proteínas de Insectos/metabolismo , Manduca/enzimología , Tribolium/enzimología , Secuencia de Aminoácidos , Animales , Ácido Ascórbico/química , Ceruloplasmina/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Compuestos Ferrosos/química , Hemolinfa/enzimología , Proteínas de Insectos/genética , Cinética , Datos de Secuencia Molecular , Oxidación-Reducción , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alineación de Secuencia , Especificidad de la Especie , Especificidad por Sustrato
5.
J Org Chem ; 80(3): 1979-84, 2015 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-25560882

RESUMEN

Calcium triflate has been identified as an efficient catalyst for the cycloaddition of nitrones to donor-acceptor cyclopropanes. The reaction proceeds with good to excellent yields of the corresponding tetrahydro-1,2-oxazines with high levels of diastereoselectivity. The generality of the reaction allowed for the synthesis of tetrahydro-1,2-oxazines bearing alkyl, aryl, and heteroaromatic substitution.


Asunto(s)
Calcio/química , Ciclopropanos/química , Óxidos de Nitrógeno/química , Oxazinas/química , Catálisis , Reacción de Cicloadición , Estructura Molecular , Estereoisomerismo
6.
Proc Natl Acad Sci U S A ; 109(33): 13337-42, 2012 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-22847425

RESUMEN

Multicopper ferroxidases catalyze the oxidation of ferrous iron to ferric iron. In yeast and algae, they participate in cellular uptake of iron; in mammals, they facilitate cellular efflux. The mechanisms of iron metabolism in insects are still poorly understood, and insect multicopper ferroxidases have not been identified. In this paper, we present evidence that Drosophila melanogaster multicopper oxidase-1 (MCO1) is a functional ferroxidase. We identified candidate iron-binding residues in the MCO1 sequence and found that purified recombinant MCO1 oxidizes ferrous iron. An association between MCO1 function and iron homeostasis was confirmed by two observations: RNAi-mediated knockdown of MCO1 resulted in decreased iron accumulation in midguts and whole insects, and weak knockdown increased the longevity of flies fed a toxic concentration of iron. Strong knockdown of MCO1 resulted in pupal lethality, indicating that MCO1 is an essential gene. Immunohistochemistry experiments demonstrated that MCO1 is located on the basal surfaces of the digestive system and Malpighian tubules. We propose that MCO1 oxidizes ferrous iron in the hemolymph and that the resulting ferric iron is bound by transferrin or melanotransferrin, leading to iron storage, iron withholding from pathogens, regulation of oxidative stress, and/or epithelial maturation. These proposed functions are distinct from those of other known ferroxidases. Given that MCO1 orthologues are present in all insect genomes analyzed to date, this discovery is an important step toward understanding iron metabolism in insects.


Asunto(s)
Ceruloplasmina/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Homeostasis , Hierro/metabolismo , Oxidorreductasas/metabolismo , Aminoácidos/metabolismo , Animales , Sitios de Unión , Biocatálisis/efectos de los fármacos , Sistema Digestivo/citología , Sistema Digestivo/enzimología , Drosophila melanogaster/citología , Drosophila melanogaster/efectos de los fármacos , Femenino , Técnicas de Silenciamiento del Gen , Homeostasis/efectos de los fármacos , Inmunohistoquímica , Hierro/farmacología , Lacasa/metabolismo , Longevidad/efectos de los fármacos , Masculino , Túbulos de Malpighi/citología , Túbulos de Malpighi/enzimología , Homología de Secuencia de Aminoácido
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