The need for an intersectionality framework in precision medicine research.

Precision medicine research has seen growing efforts to increase participation of communities that have been historically underrepresented in biomedical research. Marginalized racial and ethnic communities have received particular attention, toward the goal of improving the generalizability of scientific knowledge and promoting health equity. Against this backdrop, research has highlighted three key issues that could impede the promise of precision medicine research: issues surrounding (dis)trust and representation, challenges in translational efforts to improve health outcomes, and the need for responsive community engagement. Existing efforts to address these challenges have predominantly centered on single-dimensional demographic criteria such as race, ethnicity, or sex, while overlooking how these and additional variables, such as disability, gender identity, and socioeconomic factors, can confound and jointly impact research participation. We argue that increasing cohort diversity and the responsiveness of precision medicine research studies to community needs requires an approach that transcends conventional boundaries and embraces a more nuanced, multi-layered, and intersectional framework for data collection, analyses, and implementation. We draw attention to gaps in existing work, highlight how overlapping layers of marginalization might shape and substantiate one another and affect the precision-medicine research cycle, and put forth strategies to facilitate equitable advantages from precision-medicine research to diverse participants and internally heterogeneous communities.

Structural Racism in the COVID-19 Pandemic: Moving Forward.

The COVID-19 pandemic has taken a substantial human, social and economic toll globally, but its impact on Black/African Americans, Latinx, and American Indian/Alaska Native communities in the U.S. is unconscionable. As the U.S. continues to combat the current COVID-19 cycle and prepares for future pandemics, it will be critical to learn from and rectify past and contemporary wrongs. Drawing on experiences in genomic research and intersecting areas in medical ethics, health disparities, and human rights, this article considers three key COVID-19-related issues: research to identify remedies; testing, contact tracing and surveillance; and lingering health needs and disability. It provides a pathway for the future: community engagement to develop culturally-sensitive responses to the myriad genomic/bioethical dilemmas that arise, and the establishment of a Truth and Reconciliation Commission to transition the country from its contemporary state of segregation in healthcare and health outcomes into an equitable and prosperous society for all.

Mono- and bimetallic zwitterionic chromium(0) and tungsten(0) allenyls.

A series of stable chiral (racemic), formally neutral, zwitterionic mono- and bimetallic M(CO)5[C(OEt)═C═CR(NHC)] (M = Cr, W) σ-allenyls are ready available by the addition of N-heterocyclic carbenes (NHCs) to Cr(0) and W(0) alkynyl Fischer carbene complexes. Different classes of NHCs, (e.g., 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene, and their six- and seven-membered analogues and 1,3-bis(dimethyl)imidazol-2-ylidene) were employed as nucleophiles in these C-C bond-forming reactions yielding the novel complexes in essentially quantitative yields. A systematic experimental and computational study of the electronic properties of the Cr- and W-allenyls shows that their UV-vis spectra are directly influenced by the structure of the heterocyclic moiety derived from the NHC (ring size, substituents on the N atoms) and by the nature of the metal fragment (Cr/W). The electron-releasing nature of these complexes allows them to participate in electron-transfer reactions in the ground state, leading to a type of charged α,ß-unsaturated Fischer carbenes that incorporate an NHC fragment in their structure.

Multiple EphB receptors mediate dorsal-ventral retinotopic mapping via similar bi-functional responses to ephrin-B1.

The projection from the retina to the superior colliculus in mice is organized in a retinotopic map that develops through the formation and guidance of interstitial branches extended by retinal ganglion cell axons. Bidirectional branch guidance along the lateral-medial collicular axis is critical to mapping the dorsal-ventral retinal axis. EphB receptor tyrosine kinases expressed in an overall low to high dorsal-ventral retinal gradient have been implicated in this mapping in response to the graded low to high lateral-medial expression of a ligand, ephrin-B1, in the superior colliculus. However, the relative contributions of EphBs and ephrin-B1 are not well understood. We examined EphB1, EphB2, and EphB3 mutant mice and find that each has ectopic arborizations of retinal axon branches lateral to their appropriate termination zone, with no qualitative differences in aberrant mapping, suggesting a similar role for each EphB. However, the frequency of cases with map defects progressively rises in compound EphB mutants coincident with the number of EphB null alleles from one to five of the six total alleles indicating that EphB level is critical. We analyzed branch extension in vitro and find that dorsal branches, with low EphB levels, exhibit a negative response to ephrin-B1, whereas ventral branches, with high EphB levels, exhibit a positive response to ephrin-B1. Using EphB mutant retina, we show that both of these differential branch extension responses are dependent on EphB level. Our findings show a bifunctional action of ephrin-B1 regulated by EphB levels that can account for the bidirectional extension of interstitial branches required to establish a retinotopic map.

Impact of Burnout on Daily Activities from an Occupational Therapy Perspective: A Serial Mediation Model with the IDA Scale.

BACKGROUND: Burnout syndrome is one of the most frequent health complications among workers. Acknowledging the work perspective as something basic and essential in a person's life means that this disorder can have huge implications in their most basic daily activities. METHODS: A cross-sectional, quantitative observational design was conducted with data from Spanish workers. A serial mediation model was applied to study the relationship between daily activities and burnout syndrome. For this purpose, the IDA scale was developed. CONCLUSIONS: The results show us that peoples' work situation has an impact on their daily life. There is quantitative evidence of the impact on daily life occupations and how it further decreases the levels of health and well-being of the person, on their independence and, consequently, on their quality of life.

Colestasis intrahepática del embarazo Un reto más para la obstetricia / Intrahepatic Cholestasis of Pregnancy. One More Challenge for Obstetrics

Resumen: La colestasis intrahepática del embarazo es el trastorno hepático específico más común durante la gestación; es una condición multifactorial que aparece en mujeres genéticamente susceptibles. Se caracteriza principalmente por prurito palmo-plantar de predominio nocturno, su importancia radica en su considerable morbimortalidad fetal y aunque su tratamiento es sencillo, se debe diagnosticar. Objetivo: Realizar una revisión actualizada y a detalle de la bibliografía nacional e internacional de la etiología, las pruebas diagnósticas, tratamiento, resultados perinatales y su asociación con otras patologías del embarazo. Metodología: Se realizó una búsqueda de la literatura publicada en inglés y en español en bases de datos como PubMed / MEDLINE, Ovid, MD Consult, entre otras, utilizando las palabras clave: colestasis intrahepática del embarazo, etiología, diagnóstico, tratamiento, efectos adversos perinatales, preeclampsia, embarazo múltiple. De la información obtenida se seleccionaron 64 artículos, los cuales fueron clasificados y utilizados como soporte para realizar esta revisión. Resultados: Se aporta una actualización en cuanto al diagnóstico y tratamiento de esta enfermedad para actuar como guía clínica a los profesionales de la salud. Conclusión: Esta enfermedad es una entidad importante de diagnosticar para evitar los efectos adversos fetales que implica, la principal limitación es la carencia de determinación de niveles de ácidos biliares séricos en nuestro país, por lo tanto, la sospecha clínica se convierte en la herramienta más factible para su diagnóstico e inicio oportuno de tratamiento.

Abstract: Intrahepatic cholestasis of pregnancy is the most common specific liver disorder during pregnancy, it is a multifactorial condition that appears in genetically susceptible women and it is mainly characterized by palmoplantar itching predominantly at night. Its importance lies in the considerable fetal morbidity and mortality. Although the treatment is simple, we must know how to make the diagnosis. Objective: To carry out an updated and detailed review of the national and international bibliography of etiology, diagnostic tests, treatment, perinatal results, and their association with other pregnancy pathologies. Methodology: A search of the literature published in English and Spanish was conducted in databases such as PubMed / MEDLINE, Ovid, MD Consult, and others, using the keywords: intrahepatic cholestasis of pregnancy, etiology, diagnosis, treatment, perinatal adverse effects, preeclampsia, tween pregnancy. 64 articles were selected from the obtained, which were classified and used as support to carry out this review. Results: An update regarding the diagnosis and treatment of this disease is provided, to act as a clinical guide for healthcare professionals. Conclusion: This disease is an important entity to diagnose in order to avoid the fetal adverse effects that implies. The main limitation is the lack of determination of serum bile acid levels in our country, therefore, clinical suspicion becomes the most useful tool for diagnosis and early treatment.

Assessment of multiple displacement amplification for polymorphism discovery and haplotype determination at a highly polymorphic locus, MC1R.

The identification of common genetic variants such as single nucleotide polymorphisms (SNPs) in the human genome has become central in human population genetics and evolution studies, as well as in the study of the genetic basis of complex traits and diseases. Crucial for the accurate identification of genetic variants is the availability of high quality genomic DNA (gDNA). Since popular sources of gDNA (buccal cells, lymphocytes, hair bulb) often do not yield sufficient quantities of DNA for molecular genetic applications, whole genome amplification methods have recently been introduced to generate a renewable source of double-stranded linear DNA. Here, we assess the fidelity of one method, multiple displacement amplification (MDA), which utilizes bacteriophage Phi29 DNA polymerase to generate amplified DNA from an original source of gDNA, in a representative SNP discovery and genetic association study at the melanocortin 1 receptor (MC1R) locus, a highly polymorphic gene in humans involved in skin and hair pigmentation. We observed that MDA has high fidelity for novel SNP discovery and can be a valuable tool in generating a potentially indefinite source of DNA. However, we observed an allele amplification bias that causes genotype miscalls at heterozygous sites. At loci with multiple polymorphic sites in linkage disequilibrium, such as at MC1R, this bias can create a significant number of heterozygote genotype errors that subsequently misrepresents haplotypes.

Structure and photoreactivity of stable zwitterionic group 6 metal allenyls.

The synthesis and mechanistic study of the unprecedented reactivity of a series of zwitterionic η(1)-metal allenyls are reported.

Validez de la glucemia en ayuno como prueba diagnóstica para diabetes gestacional durante el primer trimestre del embarazo / Validity of blood glucose fasting test as diagnostic for gestational diabetes during the first trimester of pregnancy

Resumen Objetivo Determinar la validez de la glucemia en ayuno como valor único para establecer el diagnóstico de diabetes gestacional en el primer trimestre del embarazo. Calcular la sensibilidad, especificidad, valor predictivo positivo y negativo de esta prueba comparándola con el patrón de referencia "curva de tolerancia a la glucosa". Materiales y métodos Estudio observacional, retrospectivo, de casos y controles efectuado de 2014 a 2017. En el grupo de casos se incluyeron pacientes con diagnóstico de diabetes gestacional establecido entre las semanas 24 a 28 de embarazo mediante una curva de tolerancia a la glucosa. Para obtener el grupo control con resultado negativo de la curva se hizo un muestreo aleatorio. El análisis estadístico se efectuó con SPSS Statistics. Para la validez de la prueba se calculó la sensibilidad, especificidad, valores predictivos positivo y negativo. Resultados En el grupo de casos se obtuvieron 204 pacientes: 68.1% con glucemia en ayuno ≥ 92 mg/dL y 31.9% con valores normales de glucosa en el primer trimestre del embarazo. El 50% de las pacientes con sobrepeso y 100% de las pacientes con obesidad tuvieron glucemias ≥ 92 mg/dL. En el grupo control (n = 204) sólo 5.3% tuvo valores ≥ 92mg/dL. La razón de momios para diabetes gestacional con este valor de glucosa en el primer trimestre fue de 37.5; IC95%: 19.1-73.7. La sensibilidad de la prueba fue de 68% y la especificidad de 95%. Valor predictivo positivo de 93% y valor predictivo negativo de 75%. Conclusiones El valor de la glucosa en ayuno como única prueba diagnóstica de diabetes gestacional durante el primer trimestre tiene sensibilidad aceptable y buena especificidad en cualquier paciente con sobrepeso u obesidad.

Abstract Objectives To determine the validity of fasting blood glucose as the only value to perform the diagnosis of gestational diabetes in the first trimester of pregnancy, according to the criteria of the IADPSG. To calculate the sensitivity, specificity, positive and negative predictive value of this test comparing it with the gold standard "Oral glucose tolerance test". Materials and methods Case-control retrospective study carried out from 2014 to 2017. In the case group, patients diagnosed with gestational diabetes were included in the week 24 to 28 of pregnancy through an oral glucose tolerance test. Fasting blood glucose was recorded in the first trimester of pregnancy. A random sampling was done to obtain the control group with the result of the negative test. Statistical analysis was performed with SPSS Statistics. For the valid ity of the test, sensitivity, specificity, PPV, NPV, positive and negative likelihood ratio were calculated. Results In the case group, 204 patients were obtained, 68.1% with fasting blood glucose ≥ 92 mg/dL and 31.9% with normal glucose values in the first trimester of pregnancy. 50% of overweight patients and 100% of patients with obesity had glycemia ≥ 92 mg/dL. In the control group of 204 patients, only 5.3% had values ≥ 92 mg/dL. The OR for the development of gestational diabetes with this glucose value in the first trimester was 37.5 95%CI: 19.1-73.7. The sensitivity of the test was 68%, specificity 95%. Conclusions The fasting glucose value as the only diagnostic test of gestational diabetes during the first trimester has an acceptable sensitivity and a good specificity especially in patients with overweight or obesity.

p75(NTR) mediates ephrin-A reverse signaling required for axon repulsion and mapping.

Reverse signaling by ephrin-As upon binding EphAs controls axon guidance and mapping. Ephrin-As are GPI-anchored to the membrane, requiring that they complex with transmembrane proteins that transduce their signals. We show that the p75 neurotrophin receptor (NTR) serves this role in retinal axons. p75(NTR) and ephrin-A colocalize within caveolae along retinal axons and form a complex required for Fyn phosphorylation upon binding EphAs, activating a signaling pathway leading to cytoskeletal changes. In vitro, retinal axon repulsion to EphAs by ephrin-A reverse signaling requires p75(NTR), but repulsion to ephrin-As by EphA forward signaling does not. Constitutive and retina-specific p75(NTR) knockout mice have aberrant anterior shifts in retinal axon terminations in superior colliculus, consistent with diminished repellent activity mediated by graded ephrin-A reverse signaling induced by graded collicular EphAs. We conclude that p75(NTR) is a signaling partner for ephrin-As and the ephrin-A- p75(NTR) complex reverse signals to mediate axon repulsion required for guidance and mapping.

Ephrin-B ligands play a dual role in the control of neural crest cell migration.

Little is known about the mechanisms that direct neural crest cells to the appropriate migratory pathways. Our aim was to determine how neural crest cells that are specified as neurons and glial cells only migrate ventrally and are prevented from migrating dorsolaterally into the skin, whereas neural crest cells specified as melanoblasts are directed into the dorsolateral pathway. Eph receptors and their ephrin ligands have been shown to be essential for migration of many cell types during embryonic development. Consequently, we asked if ephrin-B proteins participate in the guidance of melanoblasts along the dorsolateral pathway, and prevent early migratory neural crest cells from invading the dorsolateral pathway. Using Fc fusion proteins, we detected the expression of ephrin-B ligands in the dorsolateral pathway at the stage when neural crest cells are migrating ventrally. Furthermore, we show that ephrins block dorsolateral migration of early-migrating neural crest cells because when we disrupt the Eph-ephrin interactions by addition of soluble ephrin-B ligand to trunk explants, early neural crest cells migrate inappropriately into the dorsolateral pathway. Surprisingly, we discovered the ephrin-B ligands continue to be expressed along the dorsolateral pathway during melanoblast migration. RT-PCR analysis, in situ hybridisation, and cell surface-labelling of neural crest cell cultures demonstrate that melanoblasts express several EphB receptors. In adhesion assays, engagement of ephrin-B ligands to EphB receptors increases melanoblast attachment to fibronectin. Cell migration assays demonstrate that ephrin-B ligands stimulate the migration of melanoblasts. Furthermore, when Eph signalling is disrupted in vivo, melanoblasts are prevented from migrating dorsolaterally, suggesting ephrin-B ligands promote the dorsolateral migration of melanoblasts. Thus, transmembrane ephrins act as bifunctional guidance cues: they first repel early migratory neural crest cells from the dorsolateral path, and then later stimulate the migration of melanoblasts into this pathway. The mechanisms by which ephrins regulate repulsion or attraction in neural crest cells are unknown. One possibility is that the cellular response involves signalling to the actin cytoskeleton, potentially involving the activation of Cdc42/Rac family of GTPases. In support of this hypothesis, we show that adhesion of early migratory cells to an ephrin-B-derivatized substratum results in cell rounding and disruption of the actin cytoskeleton, whereas plating of melanoblasts on an ephrin-B substratum induces the formation of microspikes filled with F-actin.