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1.
Immunol Rev ; 322(1): 311-328, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38306168

RESUMEN

Inborn errors of immunity (IEIs) encompass a diverse spectrum of genetic disorders that disrupt the intricate mechanisms of the immune system, leading to a variety of clinical manifestations. Traditionally associated with an increased susceptibility to recurrent infections, IEIs have unveiled a broader clinical landscape, encompassing immune dysregulation disorders characterized by autoimmunity, severe allergy, lymphoproliferation, and even malignancy. This review delves into the intricate interplay between IEIs and the JAK-STAT signaling pathway, a critical regulator of immune homeostasis. Mutations within this pathway can lead to a wide array of clinical presentations, even within the same gene. This heterogeneity poses a significant challenge, necessitating individually tailored therapeutic approaches to effectively manage the diverse manifestations of these disorders. Additionally, JAK-STAT pathway defects can lead to simultaneous susceptibility to both infection and immune dysregulation. JAK inhibitors, with their ability to suppress JAK-STAT signaling, have emerged as powerful tools in controlling immune dysregulation. However, questions remain regarding the optimal selection and dosing regimens for each specific condition. Hematopoietic stem cell transplantation (HSCT) holds promise as a curative therapy for many JAK-STAT pathway disorders, but this procedure carries significant risks. The use of JAK inhibitors as a bridge to HSCT has been proposed as a potential strategy to mitigate these risks.


Asunto(s)
Enfermedades del Sistema Inmune , Inhibidores de las Cinasas Janus , Humanos , Transducción de Señal , Inhibidores de las Cinasas Janus/uso terapéutico , Inhibidores de las Cinasas Janus/farmacología , Quinasas Janus/metabolismo , Factores de Transcripción STAT/metabolismo
2.
Artículo en Inglés | MEDLINE | ID: mdl-39316673

RESUMEN

There is increasing evidence that third hand exposure to e-cigarette vapor (e-vapor) can have detrimental effects on the lungs. However, whether maternal exposure during pregnancy results in harmful changes to the offspring is unknown. Using two different e-cigarette settings (low versus high power), BALB/c mice were subjected to third hand e-vapor (e-vapor deposited onto towels, towels changed daily) in the absence or presence of nicotine, before, during, and after pregnancy. Male adult offspring were then infected with mouse-adapted influenza A virus (A/PR/8/34 H1N1) and lung and bone marrow immune cell responses assessed 7 days post infection. Maternal third hand exposure to low power (MLP) or high power (MHP) e-vapor with nicotine (MLP+NIC and MHP+NIC, respectively) increased the percentage of lung immune cells and neutrophils in the bone marrow. Interestingly, Flu-infected offspring from MLP+NIC and MHP+NIC groups had lower percentages of lung alveolar macrophages, and more pronounced increases in neutrophils in the bone marrow, when compared to offspring from MSham Flu controls. Flu infection also decreased the percentage of lung CD4+ T cells and increased the percentage of lung CD8+ T cells, irrespective of maternal exposure (MLP-/+NIC and MHP-/+NIC). Significantly, both MLP+NIC and MHP+NIC resulted in blunted activation of lung CD4+ T cells, but only MLP+NIC caused blunted activation of lung CD8+ T cells. Together, we show for the first time that maternal third hand exposure to e-vapor results in significant, long-lived effects on lung and bone marrow immune cell responses in offspring at baseline and in response to Flu infection.

3.
Am J Physiol Heart Circ Physiol ; 327(4): H967-H977, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39240256

RESUMEN

T-cell accumulation within the aorta promotes endothelial dysfunction and the genesis of cardiovascular disease, including hypertension and atherosclerosis. Viral infection during pregnancy is also known to mediate marked acute endothelial dysfunction, but it is not clear whether T cells are recruited to the aorta and whether the dysfunction persists postpartum. Here, we demonstrate that influenza A virus (IAV) infection during pregnancy in a murine model resulted in endothelial dysfunction of the aorta, which persisted for up to 60 days postinfection and was associated with higher levels of IFN-γ mRNA expression within the tissue. In the absence of infection, low numbers of naïve CD4+ and CD8+ T cells, central memory T cells, and effector memory T cells were observed in the aorta. However, with IAV infection, these T-cell subsets were significantly increased with a notable accumulation of IAV-specific CD8+ effector memory T cells. Critically, this increase was maintained out to at least 60 days. In contrast, IAV infection in nonpregnant female mice resulted in modest endothelial dysfunction with no accumulation of T cells within the aorta. These data, therefore, demonstrate that the aorta is a site of T-cell recruitment and retention after IAV infection during pregnancy. Although IAV-specific memory T cells could theoretically confer protection against future influenza infection, nonspecific memory T-cell activation and IFN-γ production in the aorta could also contribute to future endothelial dysfunction and cardiovascular disease.NEW & NOTEWORTHY Pregnancy is a risk factor for cardiovascular complications to influenza A virus (IAV) infection. We demonstrate that gestational IAV infection caused endothelial dysfunction of the maternal aorta, which persisted for 60 days postinfection in mice. Various T cells accumulated within the aorta at 60 days because of the infection, and this was associated with elevated levels of the proinflammatory cytokine, IFN-γ. Our study demonstrates a novel "long influenza" cardiovascular phenotype in female mice.


Asunto(s)
Aorta , Linfocitos T CD8-positivos , Virus de la Influenza A , Interferón gamma , Ratones Endogámicos C57BL , Infecciones por Orthomyxoviridae , Animales , Femenino , Embarazo , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/virología , Aorta/inmunología , Aorta/patología , Aorta/metabolismo , Interferón gamma/metabolismo , Linfocitos T CD8-positivos/inmunología , Ratones , Complicaciones Infecciosas del Embarazo/inmunología , Complicaciones Infecciosas del Embarazo/virología , Complicaciones Infecciosas del Embarazo/fisiopatología , Modelos Animales de Enfermedad , Endotelio Vascular/inmunología , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo
4.
PLoS Pathog ; 18(8): e1010703, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35930608

RESUMEN

Influenza A virus (IAV) infection during pregnancy initiates significant aortic endothelial and vascular smooth muscle dysfunction, with inflammation and T cell activation, but the details of the mechanism are yet to be clearly defined. Here we demonstrate that IAV disseminates preferentially into the perivascular adipose tissue (PVAT) of the aorta in mice. IAV mRNA levels in the PVAT increased at 1-3 days post infection (d.p.i) with the levels being ~4-8 fold higher compared with the vessel wall. IAV infection also increased Ly6Clow patrolling monocytes and Ly6Chigh pro-inflammatory monocytes in the vessel wall at 3 d.p.i., which was then followed by a greater homing of these monocytes into the PVAT at 6 d.p.i. The vascular immune phenotype was characteristic of a "vascular storm"- like response, with increases in neutrophils, pro-inflammatory cytokines and oxidative stress markers in the PVAT and arterial wall, which was associated with an impairment in endothelium-dependent relaxation to acetylcholine. IAV also triggered a PVAT compartmentalised elevation in CD4+ and CD8+ activated T cells. In conclusion, the PVAT of the aorta is a niche that supports IAV dissemination and a site for perpetuating a profound innate inflammatory and adaptive T cell response. The manifestation of this inflammatory response in the PVAT following IAV infection may be central to the genesis of cardiovascular complications arising during pregnancy.


Asunto(s)
Virus de la Influenza A , Tejido Adiposo , Animales , Aorta , Endotelio Vascular , Femenino , Inflamación/genética , Ratones , Embarazo
5.
Arch Biochem Biophys ; 755: 109966, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537870

RESUMEN

Flavin disulfide reductases (FDRs) are FAD-dependent enzymes that transmit electrons from NAD(P)H to reduce specific oxidant substrate disulfides. These enzymes have been studied extensively, most particularly the paradigm examples: glutathione reductase and thioredoxin reductase. The common, though not universal, traits of the family include a tyrosine- or phenylalanine-gated binding pocket for NAD(P) nicotinamides adjacent to the FAD isoalloxazine re-face, and a disulfide stacked against the si-face of the isoalloxazine whose dithiol form is activated for subsequent exchange reactions by a nearby histidine acting as a base. This arrangement promotes transduction of the reducing equivalents for disulfide exchange relay reactions. From an observational standpoint the proximal parallel stacking of three redox moieties induces up to three opportunities for unique charge transfer interactions (NAD(P)H FAD, NAD(P)+•FADH2, and FAD•thiolate). In transient state, the charge transfer transitions provide discrete signals to assign reaction sequences. This review summarizes the lineage of observations for the FDR enzymes that have been extensively studied. Where applicable and in order to chart a consistent interpretation of the record, only data derived from studies that used anaerobic methods are cited. These data reveal a recurring theme for catalysis that is elaborated with specific additional functionalities for each oxidant substrate.

6.
Arch Biochem Biophys ; : 110162, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39322101

RESUMEN

Thioredoxin/glutathione reductase from Schistosoma mansoni (SmTGR) is a multifunctional enzyme that catalyzes the reduction of glutathione (GSSG) and thioredoxin, as well as the deglutathionylation of peptide and non-peptide substrates. SmTGR structurally resembles known glutathione reductases (GR) and thioredoxin reductases (TrxR) but with an appended N-terminal domain that has a typical glutaredoxin (Grx) fold. Despite structural homology with known GRs, the site of glutathione reduction has frequently been reported as the Grx domain, based primarily on aerobic, steady-state kinetic measurements and x-ray crystallography. Here, we present an anaerobic characterization of a series of variant SmTGRs to establish the site of GSSG reduction as the cysteine pair most proximal to the FAD, Cys154/Cys159, equivalent to the site of GSSG reduction in GRs. Anaerobic steady-state analysis of U597C, U597S, U597C+C31S, and I592STOP SmTGR demonstrate that the Grx domain is not involved in the catalytic reduction of GSSG, as redox silencing of the C-terminus results in no modulation of the observed turnover number (∼0.025 s-1) and redox silencing of the Grx domain results in an increased observed turnover number (∼0.08 s-1). Transient-state single turnover analysis of these variants corroborates this, as the slowest rate observed titrates hyperbolically with GSSG concentration and approaches a limit that coincides with the respective steady-state turnover number for each variant. Numerical integration fitting of the transient state data can only account for the observed trends when competitive binding of the C-terminus is included, indicating that the partitioning of electrons to either substrate occurs at the Cys154/Cys159 disulfide rather than the previously proposed Cys596/Sec597 sulfide/selenide. Paradoxically, truncating the C-terminus at Ile592 results in a loss of GR activity, indicating a crucial non-redox role for the C-terminus.

7.
Brain Behav Immun ; 120: 488-498, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38925418

RESUMEN

Influenza A virus (IAV) infection during pregnancy can increase the risk for neurodevelopmental disorders in the offspring, however, the underlying neurobiological mechanisms are largely unknown. To recapitulate viral infection, preclinical studies have traditionally focused on using synthetic viral mimetics, rather than live IAV, to examine consequences of maternal immune activation (MIA)-dependent processes on offspring. In contrast, few studies have used live IAV to assess effects on global gene expression, and none to date have addressed whether moderate IAV, mimicking seasonal influenza disease, alters normal gene expression trajectories in different brain regions across different stages of development. Herein, we show that moderate IAV infection during pregnancy, which causes mild maternal disease and no overt foetal complications in utero, induces lasting effects on the offspring into adulthood. We observed behavioural changes in adult offspring, including disrupted prepulse inhibition, dopaminergic hyper-responsiveness, and spatial recognition memory deficits. Gene profiling in the offspring brain from neonate to adolescence revealed persistent alterations to normal gene expression trajectories in the prefronal cortex, hippocampus, hypothalamus and cerebellum. Alterations were found in genes involved in inflammation and neurogenesis, which were predominately dysregulated in neonatal and early adolescent offspring. Notably, late adolescent offspring born from IAV infected mice displayed altered microglial morphology in the hippocampus. In conclusion, we show that moderate IAV during pregnancy perturbs neurodevelopmental trajectories in the offspring, including alterations in the neuroinflammatory gene expression profile and microglial number and morphology in the hippocampus, resulting in behavioural changes in adult offspring. Such early perturbations may underlie the vulnerability in human offspring for the later development of neurodevelopmental disorders, including schizophrenia. Our work highlights the importance of using live IAV in developing novel preclinical models that better recapitulate the real-world impact of inflammatory insults during pregnancy on offspring neurodevelopmental trajectories and disease susceptibility later in life.


Asunto(s)
Encéfalo , Virus de la Influenza A , Infecciones por Orthomyxoviridae , Efectos Tardíos de la Exposición Prenatal , Animales , Femenino , Embarazo , Ratones , Encéfalo/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Infecciones por Orthomyxoviridae/metabolismo , Complicaciones Infecciosas del Embarazo/metabolismo , Masculino , Ratones Endogámicos C57BL , Hipocampo/metabolismo , Trastornos del Neurodesarrollo/metabolismo , Trastornos del Neurodesarrollo/genética , Expresión Génica , Modelos Animales de Enfermedad
8.
AIDS Behav ; 28(6): 2023-2033, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38489139

RESUMEN

Minority stressors have been linked to HIV risk behaviors among gay, bisexual, queer, and other men who have sex with men (MSM). Committed partnerships are a key context for new HIV infections and coping with minority stress among MSM, but very little work has tested the minority stress-HIV risk link among male couples, and little is known about how processes within one's relationship may exacerbate or buffer this association. The present study examined links between minority stress (i.e., internalized stigma, microaggressions) and HIV transmission risk behaviors (i.e., condomless anal sex with outside partners, breaks in relationship agreements) among male couples, as well as relationship-based moderators (i.e., social support, dyadic coping) of these associations. An analytic sample of male couples from a large cohort study (analytic N = 410 individuals, 205 dyads) completed self-report measures of minority stress, relationship-based moderators, and HIV transmission risk behaviors which were submitted to moderated actor-partner interdependence models (APIMs). In many cases, coping with stress with one's partner buffered the minority stress-HIV transmission link risk. However, findings also suggested situations in which partners may overburden one another with coping, thus exacerbating HIV-related risk behaviors.


Asunto(s)
Infecciones por VIH , Homosexualidad Masculina , Grupos Minoritarios , Asunción de Riesgos , Parejas Sexuales , Apoyo Social , Estrés Psicológico , Humanos , Masculino , Infecciones por VIH/psicología , Infecciones por VIH/epidemiología , Estrés Psicológico/psicología , Estrés Psicológico/epidemiología , Adulto , Parejas Sexuales/psicología , Homosexualidad Masculina/psicología , Homosexualidad Masculina/estadística & datos numéricos , Grupos Minoritarios/psicología , Grupos Minoritarios/estadística & datos numéricos , Minorías Sexuales y de Género/psicología , Minorías Sexuales y de Género/estadística & datos numéricos , Adaptación Psicológica , Persona de Mediana Edad , Estigma Social , Conducta Sexual/psicología , Estudios de Cohortes , Sexo Inseguro/psicología , Sexo Inseguro/estadística & datos numéricos , Composición Familiar
9.
J Phys Chem A ; 128(38): 8198-8208, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39285699

RESUMEN

The content and multiphase chemistry of iron (Fe) in multicomponent atmospheric aerosols are important to global climate and oceanic models. To date, reported dissolution rates of Fe span orders of magnitude with no quantifiable dependency on the content of basic minerals that coexist with Fe. Here, we report dissolution rates of Fe in simulated dark atmospheric aging of fully characterized multielement particles under acidic conditions (bulk pH 1 or 3) with and without oxalic acid and pyrocatechol. Our main findings are (a) the total amount of Ca and Mg was higher in coal fly ash than in Arizona test dust, (b) Fe dissolution initial rates increased exponentially with %Ca/Al and %Mg/Al below 50%, (c) a reduction in the Fe dissolution initial rate was observed with %Ca/Al higher than 50%, (d) reactive Ca and Mg minerals increased the calculated initial pH at the liquid/solid interface to values higher by only 1.5-2 units than the measured bulk pH, yet interfacial water remained acidic for Fe dissolution to take place, and (e) reactive Ca and Mg minerals enhanced the deprotonation of organics at the interface, aiding in ligand-promoted dissolution of Fe. The impact of these results is discussed within the context of constraining Fe dissolution kinetic models.

10.
Subst Use Misuse ; : 1-11, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39275954

RESUMEN

Background: Although health anxiety is broadly related to the overutilization of healthcare, limited research has examined this relation among individuals with substance use disorders (SUDs), or the extent to which racial/ethnic differences influence this relationship. Objectives: The purpose of the current study is to examine the moderating role of racial/ethnic minoritized background in the relationship between health anxiety and treatment utilization among individuals with SUDs. In the present study, patients with SUDs receiving residential treatment in Mississippi (N=118; 62% racial/ethnic minoritized status, 35.6% White) completed a measure of health anxiety and answered questions about past mental health, physical health, and substance use treatment. Regression models examined whether racial/ethnic minoritized status (White vs. racial/ethnic minoritized status) moderated the relation of health anxiety to treatment utilization among patients with SUDs. Treatment utilization was examined by asking whether participants had seen a doctor or mental health provider, engaged in substance use treatment, or alcohol treatment prior to their current treatment (dichotomous), as well as the number of times they had engaged in each treatment (physical health, mental health, substance use, and alcohol treatment) in the past year (continuous). Results: Results revealed that the facets of health anxiety involving concerns about pain and disease phobia were positively associated with treatment utilization, but only among racial/ethnic minoritized participants, with concerns about pain positively associated with self-reported physical health treatment utilization (OR=0.70, 95% CI=0.50; 0.97) and disease phobia positively associated with past mental health (B = 0.36, p = 0.023) and alcohol use treatment (B=-0.23, p=.009). Conversely, disease phobia was related to less prior alcohol use treatment among White participants (B=-0.23, p=.009). Conclusions: Overall, among patients in residential treatment for SUDs, racial/ethnic minoritized participants with SUDs reported more health anxiety compared to white participants, and certain facets of health anxiety (i.e., concerns about pain and worry about severe illness) were linked to heightened treatment utilization among racial/ethnic minoritized individuals.

11.
J Allergy Clin Immunol ; 151(4): 1081-1095, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36228738

RESUMEN

BACKGROUND: In 2014, germline signal transducer and activator of transcription (STAT) 3 gain-of-function (GOF) mutations were first described to cause a novel multisystem disease of early-onset lymphoproliferation and autoimmunity. OBJECTIVE: This pivotal cohort study defines the scope, natural history, treatment, and overall survival of a large global cohort of patients with pathogenic STAT3 GOF variants. METHODS: We identified 191 patients from 33 countries with 72 unique mutations. Inclusion criteria included symptoms of immune dysregulation and a biochemically confirmed germline heterozygous GOF variant in STAT3. RESULTS: Overall survival was 88%, median age at onset of symptoms was 2.3 years, and median age at diagnosis was 12 years. Immune dysregulatory features were present in all patients: lymphoproliferation was the most common manifestation (73%); increased frequencies of double-negative (CD4-CD8-) T cells were found in 83% of patients tested. Autoimmune cytopenias were the second most common clinical manifestation (67%), followed by growth delay, enteropathy, skin disease, pulmonary disease, endocrinopathy, arthritis, autoimmune hepatitis, neurologic disease, vasculopathy, renal disease, and malignancy. Infections were reported in 72% of the cohort. A cellular and humoral immunodeficiency was observed in 37% and 51% of patients, respectively. Clinical symptoms dramatically improved in patients treated with JAK inhibitors, while a variety of other immunomodulatory treatment modalities were less efficacious. Thus far, 23 patients have undergone bone marrow transplantation, with a 62% survival rate. CONCLUSION: STAT3 GOF patients present with a wide array of immune-mediated disease including lymphoproliferation, autoimmune cytopenias, and multisystem autoimmunity. Patient care tends to be siloed, without a clear treatment strategy. Thus, early identification and prompt treatment implementation are lifesaving for STAT3 GOF syndrome.


Asunto(s)
Enfermedades del Sistema Inmune , Síndromes de Inmunodeficiencia , Niño , Humanos , Autoinmunidad/genética , Estudios de Cohortes , Mutación con Ganancia de Función , Síndromes de Inmunodeficiencia/genética , Mutación , Factor de Transcripción STAT3/genética , Proliferación Celular , Linfocitos
12.
Biochemistry ; 62(9): 1497-1508, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37071546

RESUMEN

Thioredoxin/glutathione reductase from Schistosoma mansoni (SmTGR) catalyzes the reduction of both oxidized thioredoxin and glutathione with electrons from reduced nicotinamide adenine dinucleotide phosphate (NADPH). SmTGR is a drug target for the treatment of Schistosomiasis, an infection caused by Schistosoma platyhelminths residing in the blood vessels of the host. Schistosoma spp. are reliant on TGR enzymes as they lack catalase and so use reduced thioredoxin and glutathione to regenerate peroxiredoxins consumed in the detoxification of reactive oxygen species. SmTGR is a flavin adenine dinucleotide (FAD)-dependent enzyme, and we have used the flavin as a spectrophotometric reporter to observe the movement of electrons within the enzyme. The data show that NADPH fractionally reduces the active site flavin with an observed rate constant estimated in this study to be ∼3000 s-1. The flavin then reoxidizes by passing electrons at a similar rate to the proximal Cys159-Cys154 disulfide pair. The dissociation of NADP+ occurs with a rate of ∼180 s-1, which induces the deprotonation of Cys159, and this coincides with the accumulation of an intense FAD-thiolate charge transfer band. It is proposed that the electrons then pass to the Cys596-Cys597 disulfide pair of the associated subunit in the dimer with a net rate constant of ∼2 s-1. (Note: Cys597 is Sec597 in wild-type (WT) SmTGR.) From this position, the electrons can be passed to oxidized thioredoxin or further into the protein to reduce the Cys28-Cys31 disulfide pair of the originating subunit of the dimer. From the Cys28-Cys31 center, electrons can then pass to oxidized glutathione that has a binding site directly adjacent.


Asunto(s)
Flavina-Adenina Dinucleótido , Schistosoma mansoni , Animales , Schistosoma mansoni/metabolismo , Glutatión Reductasa/metabolismo , NADP/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Reductasa de Tiorredoxina-Disulfuro/metabolismo , Glutatión/metabolismo , Disulfuros , Tiorredoxinas/metabolismo , Oxidación-Reducción
13.
Arch Biochem Biophys ; 736: 109517, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36681231

RESUMEN

Dihydropyrimidine dehydrogenase (DPD) is a flavin dependent enzyme that catalyzes the reduction of the 5,6-vinylic bond of pyrimidines uracil and thymine with electrons from NADPH. DPD has two active sites that are separated by ∼60 Å. At one site NADPH binds adjacent to an FAD cofactor and at the other pyrimidine binds proximal to an FMN. Four Fe4S4 centers span the distance between these active sites. It has recently been established that the enzyme undergoes reductive activation prior to reducing the pyrimidine. In this initial process NADPH is oxidized at the FAD site and electrons are transmitted to the FMN via the Fe4S4 centers to yield the active state with a cofactor set of FAD•4(Fe4S4)•FMNH2. The catalytic chemistry of DPD can be studied in transient-state by observation of either NADPH consumption or charge transfer absorption associated with complexation of NADPH adjacent to the FAD. Here we have utilized both sets of absorption transitions to find evidence for specific additional aspects of the DPD mechanism. Competition for binding with NADP+ indicates that the two charge transfer species observed in activation/single turnover reactions arise from NADPH populating the FAD site before and after reductive activation. An additional charge transfer species is observed to accumulate at longer times when high NADPH concentrations are mixed with the enzyme•pyrimidine complex and this data can be modelled based on asymmetry in the homodimer. It was also shown that, like pyrimidines, dihydropyrimidines induce rapid reductive activation indicating that the reduced pyrimidine formed in turnover can stimulate the reinstatement of the active state of the enzyme. Investigation of the reverse reaction revealed that dihydropyrimidines alone can reductively activate the enzyme, albeit inefficiently. In the presence of dihydropyrimidine and NADP+ DPD will form NADPH but apparently without measurable reductive activation. Pyrimidines that have 5-substituent halogens were utilized to probe both reductive activation and turnover. The linearity of the Hammett plot based on the rate of hydride transfer to the pyrimidine establishes that, at least to the radius of an iodo-group, the 5-substituent volume does not have influence on the observed kinetics of pyrimidine reduction.


Asunto(s)
Dihidrouracilo Deshidrogenasa (NADP) , Pirimidinas , Animales , Oxidación-Reducción , Dihidrouracilo Deshidrogenasa (NADP)/química , NADP/metabolismo , Espectrofotometría , Pirimidinas/metabolismo , Cinética , Flavina-Adenina Dinucleótido/química , Mamíferos/metabolismo
14.
Arch Sex Behav ; 52(6): 2539-2560, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37103633

RESUMEN

Risky sexual behaviors (RSBs) incur large societal and personal costs. Despite widespread prevention efforts, RSBs and associated consequences (e.g., sexually transmitted infections) continue to rise. A proliferation of research has emerged on situational (e.g., alcohol use) and individual difference (e.g., impulsivity) factors to explain this rise, but these approaches assume an unrealistically static mechanism underlying RSB. Because this prior research has resulted in few compelling effects, we sought to innovate by examining the interaction of situation and individual differences in explaining RSBs. A large sample (N = 105) completed baseline reports of psychopathology and 30 daily diary reports of RSBs and associated contexts. These data were submitted to multilevel models including cross-level interactions to test a person-by-situation conceptualization of RSBs. Results suggested that RSBs are most strongly predicted from interactions of person- and situation-level factors in both protective and facilitative directions. These interactions outnumbered main effects and commonly included partner commitment as a central mechanism. These results point to theoretical and clinical gaps in preventing RSB and urge a departure from prior ways of conceptualizing sexual risk as a static outcome.


Asunto(s)
Individualidad , Enfermedades de Transmisión Sexual , Humanos , Conducta Sexual , Asunción de Riesgos , Consumo de Bebidas Alcohólicas
15.
Arch Sex Behav ; 52(5): 2097-2110, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37351709

RESUMEN

Research shows that, for different sex couples, individual levels of substance use are deleterious for relationship quality (e.g., satisfaction, intimate partner aggression), whereas dyadic concordance is usually protective. However, there has been no research on these effects among male couples, even though they show increased risk for substance use and certain indices of relationship distress (e.g., intimate partner aggression) compared to different sex couples. Male partners also display distinct similarity patterns and norms surrounding substance use, suggesting that there might be unique effects of substance use on relationship quality among this population. We conducted actor-partner interdependence models of substance use on relationship quality (intimate partner aggression, satisfaction) among a large sample of male dyads (N = 934 individuals, N = 467 dyads). Results suggested that there are novel actor, partner, and similarity effects that imply unique pathways to relationship well-being for male couples. These results are discussed in light of future clinical and empirical efforts. [NCT03186534 - 6/12/2017; NCT03284541 - 6/23/2017].


Asunto(s)
Conducta Sexual , Trastornos Relacionados con Sustancias , Humanos , Masculino , Agresión , Relaciones Interpersonales , Parejas Sexuales , Trastornos Relacionados con Sustancias/epidemiología , Adulto Joven
16.
Biochemistry ; 60(40): 3027-3039, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34569786

RESUMEN

Guanosine triphosphate (GTP) cyclohydrolase II (RibA) is one of three enzymes that hydrolytically cleave the C8-N9 bond of the GTP guanine. RibA also catalyzes a subsequent hydrolytic attack at the base liberating formate and in addition cleaves the α-ß phosphodiester bond of the triphosphate to form pyrophosphate (PPi). These hydrolytic reactions are promoted by tandem active-site metal ions, zinc and magnesium, that respectively function at the GTP guanine and triphosphate moieties. The RibA reaction is part of riboflavin biosynthesis and forms 2,5-diamino-6-ß-pyrimidinone 5'-phosphate, an exocyclic pyrimidine nucleotide that ultimately forms the pyrimidine ring of the isoalloxazine of riboflavin. The stoichiometry of the RibA reaction was defined in the study that first identified this activity in Escherichia coli (Foor, F., Brown, G. M. J. Biol. Chem., 1975, 250, 9, 3545-3551) and has not been quantitatively evaluated in subsequent works. Using primarily transient state approaches we examined the interaction of RibA from E. coli with the GTP, inosine triphosphate, and PPi. Our data indicate that PPi is a slow substrate for RibA that is cleaved to form two phosphate ions (Pi). A combination of real-time enzymatically coupled Pi reporter assays and end-point 31P NMR revealed that Pi is formed at a catalytically relevant rate in the native reaction of RibA with GTP, redefining the reaction stoichiometry. Furthermore, our data indicate that both PPi and GTP stimulate conformational changes prior to hydrolytic chemistry, and we conclude that the cleavage of PPi bound as a substrate or an intermediate state results in conformational relaxation.


Asunto(s)
Proteínas de Escherichia coli/química , Escherichia coli/enzimología , GTP Ciclohidrolasa/química , Biocatálisis , Difosfatos/metabolismo , Proteínas de Escherichia coli/metabolismo , GTP Ciclohidrolasa/metabolismo , Guanosina Trifosfato/metabolismo , Inosina Trifosfato/metabolismo , Cinética , Unión Proteica , Pirofosfatasas/química , Pirofosfatasas/metabolismo
17.
Immunology ; 164(2): 386-397, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34056709

RESUMEN

There is growing interest in understanding antibody (Ab) function beyond neutralization. The non-structural protein 1 (NS1) of Zika virus (ZIKV) is an attractive candidate for an effective vaccine as Abs against NS1, unlike the envelope or premembrane, do not carry the risk of mediating antibody-dependent enhancement. Our aim was to evaluate whether ZIKV NS1 Abs elicited following natural infection in humans can mediate antibody-dependent cellular cytotoxicity (ADCC). We evaluated the isotype specificity of ZIKV-specific Abs in immune sera and supernatants from stimulated immune PBMC and found that Abs against ZIKV NS1 and virus-like particles were predominantly of the IgG1 isotype. Using a recently developed FluoroSpot assay, we found robust frequencies of NS1-specific Ab-secreting cells in PBMC of individuals who were naturally infected with ZIKV. We developed assays to measure both natural killer cell activation by flow cytometry and target cell lysis of ZIKV NS1-expressing cells using an image cytometry assay in the presence of ZIKV NS1 Abs. Our data indicate efficient opsonization of ZIKV NS1-expressing CEM-NKR cell lines using ZIKV-immune but not ZIKV-naïve sera, a prerequisite of ADCC. Furthermore, sera from immune donors were able to induce both NK cell degranulation and lysis of ZIKV NS1 CEM-NKR cells in vitro. Our data suggest that ADCC is a possible mechanism for ZIKV NS1 Abs to eliminate virally infected target cells.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Proteínas no Estructurales Virales/inmunología , Infección por el Virus Zika/inmunología , Virus Zika/inmunología , Células Cultivadas , Reacciones Cruzadas/inmunología , Humanos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Vacunas Virales/inmunología , Infección por el Virus Zika/virología
18.
J Anat ; 239(3): 669-681, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34018180

RESUMEN

The anatomy of the primate forearm is frequently investigated in terms of locomotor mode, substrate use, and manual dexterity. Such studies typically rely upon broad, interspecific samples for which one or two representative taxa are used to characterize the anatomy of their genus or family. To interpret variation between distantly related taxa, however, it is necessary to contextualize these differences by quantifying variation at lower hierarchical levels, that is, more fine-grained representation within specific genera or families. In this study, we present a focused evaluation of the variation in muscle organization, integration, and architecture within two speciose primate families: the Callitrichidae and Lemuridae. We demonstrate that, within each lineage, several muscle functional groups exhibit substantial variation in muscle organization. Most notably, the digital extensors appear highly variable (particularly among callitrichids), with many unique configurations represented. In terms of architectural variables, both families are more conservative, with the exception of the genus Callimico-for which an increase is observed in forearm muscle mass and strength. We suggest this reflects the increased use of vertical climbing and trunk-to-trunk leaping within this genus relative to the more typically fine-branch substrate use of the other callitrichids. Overall, these data emphasize the underappreciated variation in forearm myology and suggest that overly generalized typification of a taxon's anatomy may conceal significant intraspecific and intrageneric variation therein. Thus, considerations of adaptation within the forearm musculature should endeavor to consider the full range of anatomical variation when making comparisons between multiple taxa within an evolutionary context.


Asunto(s)
Evolución Biológica , Callitrichinae/anatomía & histología , Antebrazo/anatomía & histología , Lemuridae/anatomía & histología , Músculo Esquelético/anatomía & histología , Animales , Locomoción/fisiología
19.
Nurs Res ; 69(2): 116-126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31972847

RESUMEN

BACKGROUND: The presence of cognitive impairment (CI) among hospitalized older adults (aged 85 years and older) could interfere with the identification and treatment of other important symptoms experienced by these patients. Little is known, however, about the nursing care provided to this group. Contrasting the nursing care provided to patients with and without CI may reveal important insights about symptom treatment in the CI population. OBJECTIVE: The aim of this study was to examine the relationship of CI to nursing care provided and length of stay for hospitalized older adults using standardized nursing data retrieved from electronic health records. METHODS: We conducted a comparative secondary data analysis. A data set of standardized nursing plan of care data retrieved from electronic health record data of nine units at four hospitals was analyzed. The plan of care data for this study were previously transformed into one of eight categories (family, well-being, mental comfort, physical comfort, mental, safety, functional, and physiological care). Fisher exact tests were used to compare the differences in the nursing care for hospitalized older adults with and without CI. Mixed-effects models were used to examine associations of patient's cognitive status and nursing care, and cognitive status and length of stay. RESULTS: We identified 4,354 unique patients; 746 (17%) had CI. We observed that older adults with CI were less likely to receive physical comfort care than those without CI for seven of nine units. Older adults' cognitive status was associated with the delivery of mental comfort care. In addition, a worsening in cognitive status was associated with an increase in length of stay for older adults with CI. DISCUSSION: Older adults with CI appeared to be undertreated for symptoms of pain when compared to those without CI across units. There is a need for further research to improve symptom recognition and management for this population. The presence of CI was associated with variation in nursing care provided and length of stay. Future studies that include the analysis of nursing data merged with elements stored in the electronic health record representing the contributions of other health professions are expected to provide additional insights into this gap.


Asunto(s)
Disfunción Cognitiva/enfermería , Evaluación Geriátrica , Hospitalización , Tiempo de Internación/estadística & datos numéricos , Anciano de 80 o más Años , Atención Integral de Salud/normas , Registros Electrónicos de Salud , Femenino , Humanos , Masculino
20.
J Med Libr Assoc ; 108(2): 278-285, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32256239

RESUMEN

BACKGROUND: Health care continuing education conferences are important educational events that present opportunities for structured learning, interactive sharing, and professional networking. Conference presenters frequently cite published literature, such as clinical trials, to supply an evidence-based foundation, with presenters' slides often shared with conference attendees. By using social media, these conferences can have greater impact, assist in supporting evidence-based clinical practice, and increase stakeholder engagement. CASE PRESENTATION: The authors present a case of embedding a health sciences librarian into the Annual Johns Hopkins Critical Care Rehabilitation Conference. The librarian served multiple roles, including social media ambassador, conference exhibitor, and presenter. We explore how these roles contributed to the field of early rehabilitation research through information dissemination and education. We also address best practices for librarian support of the conference, with a discussion of tools, platforms, and work flows that were beneficial. CONCLUSIONS: Librarian integration facilitated education about bibliographic literature database content, database searching, critical appraisal, and reporting of search methodology. Additionally, the librarian contributed to real-time distribution of scholarly literature through proficiency with web platforms, citation management programs, and social media. Librarians' expertise in information organization and dissemination, as well as various technology platforms, make them a valuable addition to health care conferences.


Asunto(s)
Congresos como Asunto , Educación Médica Continua , Bibliotecólogos , Rol Profesional , Congresos como Asunto/organización & administración , Educación Médica Continua/métodos , Educación Médica Continua/organización & administración , Humanos , Servicios de Biblioteca , Medios de Comunicación Sociales
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