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1.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36902373

RESUMEN

The repair of orthopedic and maxillofacial defects in modern medicine currently relies heavily on the use of autograft, allograft, void fillers, or other structural material composites. This study examines the in vitro osteo regenerative potential of polycaprolactone (PCL) tissue scaffolding, fabricated via a three-dimensional (3D) additive manufacturing technology, i.e., a pneumatic micro extrusion (PME) process. The objectives of this study were: (i) To examine the innate osteoinductive and osteoconductive potential of 3D-printed PCL tissue scaffolding and (ii) To perform a direct in vitro comparison of 3D-printed PCL scaffolding with allograft Allowash® cancellous bone cubes with regards to cell-scaffold interactions and biocompatibility with three primary human bone marrow (hBM) stem cell lines. This study specifically examined cell survival, cell integration, intra-scaffold cell proliferation, and differentiation of progenitor cells to investigate the potential of 3D-printed PCL scaffolds as an alternative to allograft bone material for the repair of orthopedic injuries. We found that mechanically robust PCL bone scaffolds can be fabricated via the PME process and the resulting material did not elicit detectable cytotoxicity. When the widely used osteogenic model SAOS-2 was cultured in PCL extract medium, no detectable effect was observed on cell viability or proliferation with multiple test groups showing viability ranges of 92.2% to 100% relative to a control group with a standard deviation of ±10%. In addition, we found that the honeycomb infill pattern of the 3D-printed PCL scaffold allowed for superior mesenchymal stem-cell integration, proliferation, and biomass increase. When healthy and active primary hBM cell lines, having documented in vitro growth rates with doubling times of 23.9, 24.67, and 30.94 h, were cultured directly into 3D-printed PCL scaffolds, impressive biomass increase values were observed. It was found that the PCL scaffolding material allowed for biomass increase values of 17.17%, 17.14%, and 18.18%, compared to values of 4.29% for allograph material cultured under identical parameters. It was also found that the honeycomb scaffold infill pattern was superior to the cubic and rectangular matrix structures, and provided a superior microenvironment for osteogenic and hematopoietic progenitor cell activity and auto-differentiation of primary hBM stem cells. Histological and immunohistochemical studies performed in this work confirmed the regenerative potential of PCL matrices in the orthopedic setting by displaying the integration, self-organization, and auto-differentiation of hBM progenitor cells within the matrix. Differentiation products including mineralization, self-organizing "proto-osteon" structures, and in vitro erythropoiesis were observed in conjunction with the documented expression of expected bone marrow differentiative markers including CD-99 (>70%), CD-71 (>60%), and CD-61 (>5%). All of the studies were conducted without the addition of any exogenous chemical or hormonal stimulation and exclusively utilized the abiotic and inert material polycaprolactone; setting this work apart from the vast majority of contemporary investigations into synthetic bone scaffold fabrication In summary, this study demonstrates the unique clinical potential of 3D-printed PCL scaffolds for stem cell expansion and incorporation into advanced microstructures created via PME manufacturing to generate a physiologically inert temporary bony defect graft with significant autograft features for enhanced end-stage healing.


Asunto(s)
Caproatos , Células Madre Mesenquimatosas , Andamios del Tejido , Humanos , Células de la Médula Ósea , Caproatos/farmacología , Osteogénesis , Poliésteres/química , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
2.
J Bacteriol ; 203(16): e0016521, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34060904

RESUMEN

The Yersinia pestis pH 6 antigen (PsaA) forms fimbria-like structures and is required for full virulence during bubonic plague. High temperature and low pH regulate PsaA production, and while recent work has uncovered the molecular aspects of temperature control, the mechanisms underlying this unusual regulation by pH are poorly understood. Using defined growth conditions, we recently showed that high levels of PsaE and PsaF (two regulatory proteins required for expression of psaA) are present at mildly acidic pH, but these levels are greatly reduced at neutral pH, resulting in low psaA expression. In prior work, the use of translational reporters suggested that pH had no impact on translation of psaE and psaF, but rather affected protein stability of PsaE and/or PsaF. Here, we investigated the pH-dependent posttranslational mechanisms predicted to regulate PsaE and PsaF stability. Using antibodies that recognize the endogenous proteins, we showed that the amount of PsaE and PsaF is defined by a distinct pH threshold. Analysis of histidine residues in the periplasmic domain of PsaF suggested that it functions as a pH sensor and indicated that the presence of PsaF is important for PsaE stability. At neutral pH, when PsaF is absent, PsaE appears to be targeted for proteolytic degradation by regulated intramembrane proteolysis. Together, our work shows that Y. pestis utilizes PsaF as a pH sensor to control psaA expression by enhancing the stability of PsaE, an essential psaA regulatory protein. IMPORTANCE Yersinia pestis is a bacterial pathogen that causes bubonic plague in humans. As Y. pestis cycles between fleas and mammals, it senses the environment within each host to appropriately control gene expression. PsaA is a protein that forms fimbria-like structures and is required for virulence. High temperature and low pH together stimulate psaA transcription by increasing the levels of two essential integral membrane regulators, PsaE and PsaF. Histidine residues in the PsaF periplasmic domain enable it to function as a pH sensor. In the absence of PsaF, PsaE (a DNA-binding protein) appears to be targeted for proteolytic degradation, thus preventing expression of psaA. This work offers insight into the mechanisms that bacteria use to sense pH and control virulence gene expression.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Membrana Celular/metabolismo , Regulación Bacteriana de la Expresión Génica , Complejo de Proteína del Fotosistema I/metabolismo , Yersinia pestis/metabolismo , Ácidos/metabolismo , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Membrana Celular/genética , Concentración de Iones de Hidrógeno , Complejo de Proteína del Fotosistema I/genética , Transporte de Proteínas , Yersinia pestis/genética
3.
FASEB J ; 34(7): 8778-8786, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32946179

RESUMEN

Reporting the sex of biological material is critical for transparency and reproducibility in science. This study examined the reporting of the sex of cells used in cardiovascular studies. Articles from 16 cardiovascular journals that publish peer-reviewed studies in cardiovascular physiology and pharmacology in the year 2018 were systematically reviewed using terms "cultured" and "cells." Data were collected on the sex of cells, the species from which the cells were isolated, and the type of cells, and summarized as a systematic review. Sex was reported in 88 (38.6%) of the 228 studies meeting inclusion criteria. Reporting rates varied with Circulation, Cardiovascular Research and American Journal of Physiology: Heart and Circulatory Physiology having the highest rates of sex reporting (>50%). A majority of the studies used cells from male (54.5%) or both male and female animals (32.9%). Humans (31.8%), rats (20.4%), and mice (43.8%) were the most common sources for cells. Cardiac myocytes were the most commonly used cell type (37.0%). Overall reporting of sex of experimental material remains below 50% and is inconsistent among journals. Sex chromosomes in cells have the potential to affect protein expression and molecular signaling pathways and should be consistently reported.


Asunto(s)
Investigación Biomédica , Sistema Cardiovascular/fisiopatología , Sistema Cardiovascular/citología , Células Cultivadas , Femenino , Humanos , Masculino , Factores Sexuales
4.
Pharm Stat ; 20(5): 929-938, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34396690

RESUMEN

Differences in patient characteristics, including age, sex, and race influence the safety and effectiveness of drugs, biologic products, and medical devices. Here we provide a summary of the topics discussed during the opening panel at the 2018 Johns Hopkins Center for Excellence in Regulatory Science and Innovation symposium on Assessing and Communicating Heterogeneity of Treatment Effects for Patient Subpopulations: Challenges and Opportunities. The goal of this session was to provide a brief overview of FDA-regulated therapeutics, including drugs, biologics and medical devices, and some of the major sources of heterogeneity of treatment effects (HTE) related to patient demographics, such as age, sex and race. The panel discussed the US Food and Drug Administration's role in reviewing and regulating drugs, devices, and biologic products and the challenges associated with ensuring that diverse patient populations benefit from these therapeutics. Ultimately, ensuring diverse demographic inclusion in clinical trials, and designing basic and clinical research studies to account for the intended patient population's age, sex, race, and genetic factors among other characteristics, will lead to better, safer therapies for diverse patient populations.


Asunto(s)
Preparaciones Farmacéuticas , United States Food and Drug Administration , Humanos , Estados Unidos
5.
J Bacteriol ; 201(16)2019 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-31138630

RESUMEN

PsaA, the subunit of the fimbria originally referred to as the "pH 6 antigen," is required for full virulence of Yersinia pestis during bubonic plague. The expression of psaA is dependent upon specific environmental signals, and while the signals (high temperature and acidic pH) are defined, the mechanisms underlying this regulation remain unclear. In the closely related species Yersinia pseudotuberculosis, psaA transcription requires two regulatory genes, psaE and psaF, and it is speculated that posttranscriptional regulation of PsaE and/or PsaF contributes to the regulation of psaA transcription. Few studies have examined the regulation of psaA expression in Y. pestis, and prior to this work, the roles of psaE and psaF in Y. pestis had not been defined. The data presented here show that both psaE and psaF are required for psaA transcription in Y. pestis and that the impact of temperature and pH is mediated through discrete posttranscriptional effects on PsaE and PsaF. By generating antibodies that recognize endogenous PsaE and PsaF, we determined that the levels of both proteins are impacted by temperature and pH. High temperature is required for psaE and psaF translation via discrete mechanisms mediated by the mRNA 5' untranslated region (UTR) upstream of each gene. Additionally, levels of PsaE and PsaF are impacted by pH. We show that PsaF enhances the stability of PsaE, and thus, both PsaE and PsaF are required for psaA transcription. Our data indicate that the environmental signals (temperature and pH) impact the expression of psaA by affecting the translation of psaE and psaF and the stability of PsaE and PsaF.IMPORTANCEY. pestis is a Gram-negative bacterial pathogen that causes bubonic plague. As a vector-borne pathogen, Y. pestis fluctuates between an arthropod vector (flea) and mammalian host. As such, Y. pestis must recognize environmental signals encountered within each host environment and respond by appropriately regulating gene expression. PsaA is a key Y. pestis mammalian virulence determinant that forms fimbriae. Our work provides evidence that Y. pestis utilizes multiple posttranscriptional mechanisms to regulate the levels of two PsaA regulatory proteins in response to both temperature and pH. This study offers insight into mechanisms that bacteria utilize to sense environmental cues and regulate the expression of determinants required for mammalian disease.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Complejo de Proteína del Fotosistema I/metabolismo , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Complejo de Proteína del Fotosistema I/genética , Temperatura , Yersinia pestis/genética , Yersinia pestis/metabolismo , Yersinia pseudotuberculosis/genética , Yersinia pseudotuberculosis/metabolismo
6.
Physiology (Bethesda) ; 33(6): 374-383, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30303778

RESUMEN

Bilateral oophorectomy in premenopausal women is a unique condition causing the abrupt and premature loss of ovarian hormones, primarily estrogen. Bilateral oophorectomy causes an alteration of several fundamental aging processes at the cellular, tissue, organ, and system levels, leading to multimorbidity, frailty, and reduced survival. However, many questions remain unanswered.


Asunto(s)
Envejecimiento/metabolismo , Hormonas Esteroides Gonadales/metabolismo , Ovario/metabolismo , Animales , Femenino , Humanos
7.
Am J Physiol Regul Integr Comp Physiol ; 317(6): R834-R839, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31663771

RESUMEN

Preeclampsia (PE) is a hypertensive disorder of pregnancy described as a condition of excessive sympathoexcitation. PE places a woman at increased risk for lifelong hypertension and cognitive impairment. Cerebral blood velocity is blunted in response to a vasoactive stimulus in women with a history of PE. This study investigated how a sympathoexcitatory stimulus affects cerebral blood velocity in women with a history of PE. Middle cerebral artery blood velocity (MCAv) and beat-to-beat mean arterial blood pressure (MAP) were measured in postmenopausal women with a history of PE (n = 21; age = 59 ± 5 yr) and a history of a normotensive pregnancy (NP; n = 27; age = 58 ± 4 yr), at baseline, during isometric handgrip to fatigue (IHG) followed by postexercise ischemia (PEI), and a recovery period (REC). Baseline MAP and MAP responses to IHG and PEI did not differ between groups. MCAv at baseline and throughout the stimulus was lower in PE women compared with NP women (P < 0.05 for all). MCAv increased during IHG in both groups (P < 0.05). This increase in MCAv was greater in PE compared with NP women during IHG and REC (IHG: PE 13 ± 2% vs. NP 9 ± 2%; REC: PE 3 ± 2% vs. NP -2 ± 2%; P < 0.05 for both). Thus, a history of PE is associated with low baseline cerebral blood velocity but an augmented response to a sympathoexcitatory stimulus. These changes in cerebral blood flow regulation may lead to an increased risk for cognitive impairment in women with a history of PE.


Asunto(s)
Presión Sanguínea/fisiología , Circulación Cerebrovascular/fisiología , Ejercicio Físico/fisiología , Posmenopausia , Preeclampsia/patología , Femenino , Fuerza de la Mano , Frecuencia Cardíaca , Humanos , Contracción Isométrica , Persona de Mediana Edad , Arteria Cerebral Media/fisiología , Embarazo
8.
Am J Physiol Regul Integr Comp Physiol ; 317(6): R912-R920, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31663769

RESUMEN

Changes in pituitary-ovarian hormones across the menopausal transition have multiple physiological consequences. However, little is known about how the major types of postmenopausal hormone therapy (HT) affect pituitary-ovarian hormonal relationships. This study evaluated these relationships in recently menopausal women (52.45 ± 2.49 yr of age) in the Kronos Early Estrogen Prevention Study (KEEPS) who were compliant to randomized, double-blinded treatment with oral conjugated equine estrogen (o-CEE; n = 109), transdermal 17ß-estradiol (t-E2; n = 107), or placebo (n = 146). Androstenedione, testosterone, 17ß-estradiol, estrone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured in serum before (baseline) and 48 mo after randomization to treatment. Descriptive summaries of hormone levels were performed, and multiple regression analyses were used to examine the effects of o-CEE, t-E2, and placebo on these hormone levels at 48 mo, adjusting for baseline levels. A network analysis examined the covariance of changes in hormone levels over the 48 mo within treatment groups. As expected, at 48 mo of treatment, hormone levels differed between women in the two active treatment groups compared with placebo, and network analysis indicated stronger relationships among hormone levels in the t-E2 and o-CEE groups compared with placebo. Associations among testosterone, 17ß-estradiol, FSH, and LH differed between the o-CEE group compared with t-E2 and placebo groups. Thus, two common HT regimens differentially alter pituitary-ovarian hormone levels, altering feedback cycles and interhormonal associations in recently menopausal women. These interactions provide the basis for future studies investigating the impact of hormonal modulation of aging, including cognitive decline in women.


Asunto(s)
Estradiol/farmacología , Menopausia/fisiología , Ovario/efectos de los fármacos , Hipófisis/efectos de los fármacos , Administración Cutánea , Método Doble Ciego , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Estrógenos/administración & dosificación , Estrógenos/farmacología , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Persona de Mediana Edad , Ovario/fisiología , Hipófisis/fisiología , Progesterona/sangre
9.
Curr Hypertens Rep ; 21(12): 93, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31741134

RESUMEN

PURPOSE OF REVIEW: Risks for developing cardiovascular disease and cognitive decline increase with age. In women, these risks may be influenced by pregnancy history. This review provides an integrated evaluation of associations of pregnancy history with hypertension, brain atrophy, and cognitive decline in postmenopausal women. RECENT FINDINGS: Atrophy in the occipital lobes of the brain was evident in women who had current hypertension and a history of preeclampsia. Deficits in visual memory in women with a history of preeclampsia are consistent with these brain structural changes. The blood velocity response to chemical and sympathoexcitatory stimuli were altered in women with a history of preeclampsia linking impairments in cerebrovascular regulation to the structural and functional changes in the brain. Having a history of preeclampsia should require close monitoring of blood pressure and initiation of anti-hypertensive treatment in perimenopausal women. Mechanisms by which preeclampsia affects cerebrovascular structure and function require additional study.


Asunto(s)
Encefalopatías/fisiopatología , Encéfalo/patología , Disfunción Cognitiva/fisiopatología , Hipertensión/etiología , Preeclampsia/fisiopatología , Historia Reproductiva , Atrofia , Presión Sanguínea , Encéfalo/irrigación sanguínea , Encéfalo/fisiopatología , Encefalopatías/etiología , Disfunción Cognitiva/etiología , Femenino , Humanos , Hipertensión/fisiopatología , Posmenopausia , Preeclampsia/tratamiento farmacológico , Embarazo
10.
FASEB J ; 31(1): 29-34, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27682203

RESUMEN

In June 2015, the National Institutes of Health (NIH) released a Guide notice (NOT-OD-15-102) that highlighted the expectation of the NIH that the possible role of sex as a biologic variable be factored into research design, analyses, and reporting of vertebrate animal and human studies. Anticipating these guidelines, the NIH Office of Research on Women's Health, in October 2014, convened key stakeholders to discuss methods and techniques for integrating sex as a biologic variable in preclinical research. The workshop focused on practical methods, experimental design, and approaches to statistical analyses in the use of both male and female animals, cells, and tissues in preclinical research. Workshop participants also considered gender as a modifier of biology. This article builds on the workshop and is meant as a guide to preclinical investigators as they consider methods and techniques for inclusion of both sexes in preclinical research and is not intended to prescribe exhaustive/specific approaches for compliance with the new NIH policy.-Miller, L. R., Marks, C., Becker, J. B., Hurn, P. D., Chen, W.-J., Woodruff, T., McCarthy, M. M., Sohrabji, F., Schiebinger, L., Wetherington, C. L., Makris, S., Arnold, A. P., Einstein, G., Miller, V. M., Sandberg, K., Maier, S., Cornelison, T. L., Clayton, J. A. Considering sex as a biological variable in preclinical research.


Asunto(s)
Investigación Biomédica/normas , Evaluación Preclínica de Medicamentos , National Institutes of Health (U.S.)/normas , Femenino , Humanos , Masculino , Factores Sexuales , Estados Unidos
11.
Adv Exp Med Biol ; 1065: 433-454, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30051400

RESUMEN

Sex differences in cardiovascular diseases can be classified as those which are specific to one sex and those that differ in incidence, prevalence, etiology, symptomatology, response to treatment, morbidity, and mortality in one sex compared to the other. All sex differences in cardiovascular conditions have their basis in the combined expression of genetic and hormonal differences between women and men. This chapter addresses how understanding basic mechanisms of hormone responses, imaging diagnostics, and integration of genomics and proteomics has advanced diagnosis and improved outcomes for cardiovascular conditions, apart from those related to pregnancy that are more prevalent in women. These conditions include obstructive coronary artery disease, coronary microvascular dysfunction, spontaneous coronary artery dissection, diseases of the cardiac muscle including heart failure and takotsubo cardiomyopathy, and conditions related to neurovascular dysregulation including hot flashes and night sweats associated with menopause and effects of exogenous hormones on vascular function. Improvement in technologies allowing for noninvasive assessment of neuronally mediated vascular reactivity will further improve our understanding of the basic etiology of the neurovascular disorders. Consideration of sex, hormonal status, and pregnancy history in diagnosis and treatment protocols will improve prevention and outcomes of cardiovascular disease in women as they age.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Enfermedades Cardiovasculares/fisiopatología , Sistema Cardiovascular/inervación , Disparidades en el Estado de Salud , Animales , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/terapia , Circulación Coronaria , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Hemodinámica , Humanos , Masculino , Menopausia , Factores de Riesgo , Caracteres Sexuales , Factores Sexuales , Función Ventricular
12.
Eur Heart J ; 38(46): 3434-3440, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29020402

RESUMEN

AIMS: Sex differences in hypertrophic cardiomyopathy (HCM) remain unclear. We sought to characterize sex differences in a large HCM referral centre population. METHODS AND RESULTS: Three thousand six hundred and seventy-three adult patients with HCM underwent evaluation between January 1975 and September 2012 with 1661 (45.2%) female. Kaplan-Meier survival curves were assessed via log-rank test. Cox proportional hazard regression analyses evaluated the relation of sex with survival. At index visit, women were older (59 ± 16 vs. 52 ± 15 years, P < 0.0001) had more symptoms [New York Heart Association (NYHA) Class III-IV 45.0% vs. 35.3%, P < 0.0001], more obstructive physiology (77.4% vs. 71.8%, P = 0.0001), more mitral regurgitation (moderate or greater in 56.1% vs. 43.9%, P < 0.0001), higher E/e' ratio (n = 1649, 20.6 vs. 15.6, P < 0.0001), higher estimated pulmonary artery systolic pressure (n = 1783, 40.8 ± 15.4 vs. 34.8 ± 10.8 mmHg, P < 0.0001), worse cardiopulmonary exercise performance (n = 1267; percent VO2 predicted 62.8 ± 20% vs. 65.8 ± 19.2%, P = 0.007), and underwent more frequent alcohol septal ablation (4.9% vs. 3.0%, P = 0.004) but similar frequency of myectomy (28% vs. 30%, P = 0.24). Median follow-up was 10.9 (IQR 7.4-16.2) years. Kaplan-Meier analysis demonstrated lower survival in women compared with men (P < 0.0001). In multivariable modelling, female sex remained independently associated with mortality (HR 1.13 [1.03-1.22], P = 0.01) when adjusted for age, NYHA Class III-IV symptoms, and cardiovascular comorbidities. CONCLUSION: Women with HCM present at more advanced age, with more symptoms, worse cardiopulmonary exercise tolerance, and different haemodynamics than men. Sex is an important determinant in HCM management as women with HCM have worse survival. Women may require more aggressive diagnostic and therapeutic approaches.


Asunto(s)
Cardiomiopatía Hipertrófica/mortalidad , Técnicas de Ablación/mortalidad , Técnicas de Ablación/estadística & datos numéricos , Cardiomiopatía Hipertrófica/terapia , Ecocardiografía , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Minnesota/epidemiología , Modelos de Riesgos Proporcionales , Distribución por Sexo
13.
Am J Physiol Heart Circ Physiol ; 313(5): H1013-H1021, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28801526

RESUMEN

The worlds of observational, clinical, and basic science collided in 2002 with the publication of results of the Women's Health Initiative (WHI), a large-scale, prospective, blinded, randomized-controlled trial designed to provide evidence regarding use of hormone treatment to prevent cardiovascular disease in menopausal women. The results of the WHI dramatically changed clinical practice, negatively impacted funding for hormone research, and left scientists to unravel the "why" of the results. Now over a decade and a half since the initial publication of the WHI results, basic and clinical scientists often do not interpret the results of the WHI with the precision needed to move the science forward. This review will 1) describe the historical background leading up to the WHI, 2) list the outcomes from the WHI, and put them in perspective with results of subsequent analysis of the WHI data and results from other prospective menopausal hormone treatment trials addressing cardiovascular effects of menopausal hormone use, and 3) articulate how the collective results are influencing current clinical care with the intent to provide guidance for designing and evaluating relevant new hormonal studies.


Asunto(s)
Investigación Biomédica , Terapia de Reemplazo de Estrógeno/métodos , Estrógenos/administración & dosificación , Posmenopausia , Factores de Edad , Animales , Comorbilidad , Esquema de Medicación , Composición de Medicamentos , Terapia de Reemplazo de Estrógeno/efectos adversos , Terapia de Reemplazo de Estrógeno/normas , Estrógenos/efectos adversos , Medicina Basada en la Evidencia , Femenino , Humanos , Seguridad del Paciente , Guías de Práctica Clínica como Asunto , Factores de Riesgo , Resultado del Tratamiento
14.
PLoS Pathog ; 11(1): e1004587, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25611317

RESUMEN

The series of events that occurs immediately after pathogen entrance into the body is largely speculative. Key aspects of these events are pathogen dissemination and pathogen interactions with the immune response as the invader moves into deeper tissues. We sought to define major events that occur early during infection of a highly virulent pathogen. To this end, we tracked early dissemination of Yersinia pestis, a highly pathogenic bacterium that causes bubonic plague in mammals. Specifically, we addressed two fundamental questions: (1) do the bacteria encounter barriers in disseminating to draining lymph nodes (LN), and (2) what mechanism does this nonmotile bacterium use to reach the LN compartment, as the prevailing model predicts trafficking in association with host cells. Infection was followed through microscopy imaging in addition to assessing bacterial population dynamics during dissemination from the skin. We found and characterized an unexpected bottleneck that severely restricts bacterial dissemination to LNs. The bacteria that do not pass through this bottleneck are confined to the skin, where large numbers of neutrophils arrive and efficiently control bacterial proliferation. Notably, bottleneck formation is route dependent, as it is abrogated after subcutaneous inoculation. Using a combination of approaches, including microscopy imaging, we tested the prevailing model of bacterial dissemination from the skin into LNs and found no evidence of involvement of migrating phagocytes in dissemination. Thus, early stages of infection are defined by a bottleneck that restricts bacterial dissemination and by neutrophil-dependent control of bacterial proliferation in the skin. Furthermore, and as opposed to current models, our data indicate an intracellular stage is not required by Y. pestis to disseminate from the skin to draining LNs. Because our findings address events that occur during early encounters of pathogen with the immune response, this work can inform efforts to prevent or control infection.


Asunto(s)
Derrame de Bacterias , Peste/microbiología , Peste/transmisión , Yersinia pestis/patogenicidad , Animales , Derrame de Bacterias/genética , Dermis/inmunología , Dermis/microbiología , Femenino , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/microbiología , Vasos Linfáticos/inmunología , Vasos Linfáticos/microbiología , Ratones , Ratones Endogámicos C57BL , Neutrófilos/inmunología , Organismos Modificados Genéticamente , Piel/inmunología , Virulencia/genética , Yersinia pestis/fisiología
15.
Am J Physiol Regul Integr Comp Physiol ; 312(1): R49-R54, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27927625

RESUMEN

Hypertensive pregnancy (HTNP) is a risk factor for future cardiovascular disease. Exaggerated cardiovascular responses to physical stress are also considered an independent marker of cardiovascular disease risk. However, there are limited data regarding the blood pressure (BP) responses to acute stress in women, who have a history of HTNP. Hence, the aim of the study is to compare BP responses to a physical stress in postmenopausal women with a history of HTNP to age- and parity-matched women with a history of normotensive pregnancy (NP). Beat-to-beat BP and heart rate was recorded in 64 postmenopausal women with [age = 58.5 (55.2, 62.2) yr, where values are the median, 25th percentile, and 75th percentile] and without [age = 59.4 (55.9, 62.4) yr] a history of HTNP before and during isometric handgrip (IHG) exercise (30% of maximal voluntary contraction) to fatigue. Muscle metaboreflex was measured during postexercise ischemia following IHG exercise. BP variables increased similarly in response to IHG exercise [systolic: NP = 11.5 (8.9, 17.6) %, HTNP = 11.3 (9.5, 15.9) %; diastolic NP = 11.2 (7.9, 13.3) %, HTNP = 9.5 (7.1, 14.3) %; mean blood pressure: NP = 9.8 (5.0, 13.6) %, and HTNP = 7.2 (4.4, 10.4) %] and postexercise ischemia [systolic: NP = 14.1 (10.3, 23.0) %, HTNP = 15.8 (10.6, 21.4) %; diastolic NP = 12.2 (4.8, 17.0) %, HTNP = 10.4 (5.3, 17.1) %; and mean blood pressure: NP = 11.1 (6.1, 17.9) %, HTNP = 9.4 (2.9, 14.8) %] in both groups. Although having a history of HTNP is associated with future cardiovascular disease risk, results from this study suggest that the risk may not be manifested through altered cardiovascular metaboreflex response to physical stressors.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Presión Sanguínea , Hipertensión Inducida en el Embarazo/fisiopatología , Músculo Esquelético/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Femenino , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Músculo Esquelético/inervación , Posmenopausia , Estrés Fisiológico
16.
Am J Kidney Dis ; 69(4): 498-505, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27707553

RESUMEN

BACKGROUND: Several registry-based studies, using diagnostic codes, have suggested that preeclampsia is a risk factor for end-stage renal disease (ESRD). However, because the 2 diseases share risk factors, the true nature of their association remains uncertain. Our goals were to conduct a population-based study to determine the magnitude of the association between preeclampsia and ESRD and evaluate the role of shared risk factors. STUDY DESIGN: Population-based nested case-control study. SETTING & PARTICIPANTS: The US Renal Data System was used to identify women with ESRD from a cohort of 34,581 women who gave birth in 1976 to 2010 in Olmsted County, MN. 44 cases of ESRD were identified and each one was matched to 2 controls based on year of birth (±1 year), age at first pregnancy (±2 years), and parity (±1 or ≥4). PREDICTOR: Preeclamptic pregnancy, confirmed by medical record review. OUTCOME: ESRD. MEASUREMENTS: Prepregnancy serum creatinine and urine protein measurements were recorded. Comorbid conditions existing prior to pregnancy were abstracted from medical records and included kidney disease, obesity, diabetes, and hypertension. RESULTS: There was evidence of kidney disease prior to the first pregnancy in 9 of 44 (21%) cases and 1 of 88 (<1%) controls. Per chart review, 8 of 44 (18%) cases versus 4 of 88 (5%) controls had preeclamptic pregnancies (unadjusted OR, 4.0; 95% CI, 1.21-13.28). Results were similar after independent adjustment for race, education, diabetes, and hypertension prior to pregnancy. However, the association was attenuated and no longer significant after adjustment for obesity (OR, 3.25; 95% CI, 0.93-11.37). LIMITATIONS: The limited number of ESRD cases and missing data for prepregnancy kidney function. CONCLUSIONS: Our findings confirm that there is a sizable association between preeclampsia and ESRD; however, obesity is a previously unexplored confounder. Pre-existing kidney disease was common, but not consistently coded or diagnosed.


Asunto(s)
Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/etiología , Preeclampsia/diagnóstico , Preeclampsia/etiología , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Comorbilidad , Creatinina/sangre , Femenino , Humanos , Pruebas de Función Renal , Obesidad/complicaciones , Obesidad/diagnóstico , Embarazo , Recurrencia , Factores de Riesgo , Estadística como Asunto , Adulto Joven
17.
Am J Obstet Gynecol ; 217(1): 74.e1-74.e11, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28322777

RESUMEN

BACKGROUND: Hypertension is a risk factor for cerebrovascular disease and cognitive impairment. Women with hypertensive episodes during pregnancy report variable neurocognitive changes within the first decade following the affected pregnancy. However, long-term follow-up of these women into their postmenopausal years has not been conducted. OBJECTIVE: The aim of this study was to examine whether women with a history of preeclampsia were at increased risk of cognitive decline 35-40 years after the affected pregnancy. STUDY DESIGN: Women were identified and recruited through the medical linkage, population-based Rochester Epidemiologic Project. Forty women with a history of preeclampsia were age- and parity-matched to 40 women with a history of normotensive pregnancy. All women underwent comprehensive neuropsychological assessment and completed self-report inventories measuring mood, ie, depression, anxiety, and other symptoms related to emotional state. Scores were compared between groups. In addition, individual cognitive scores were examined by neuropsychologists and a neurologist blinded to pregnancy status, and a clinical consensus diagnosis of normal, mild cognitive impairment, or dementia for each participant was conferred. RESULTS: Age at time of consent did not differ between preeclampsia (59.2 [range 50.9-71.5] years) and normotensive (59.6 [range 52.1-72.2] years) groups, nor did time from index pregnancy (34.9 [range 32.0-47.2] vs 34.5 [range 32.0-46.4] years, respectively). There were no statistically significant differences in raw scores on tests of cognition and mood between women with histories of preeclampsia compared to women with histories of normotensive pregnancy. However, a consensus diagnosis of mild cognitive impairment or dementia trended toward greater frequency in women with histories of preeclampsia compared to those with normotensive pregnancies (20% vs 8%, P = .10) and affected more domains among the preeclampsia group (P = .03), most strongly related to executive dysfunction (d = 1.96) and verbal list learning impairment (d = 1.93). CONCLUSION: These findings suggest a trend for women with a history of preeclampsia to exhibit more cognitive impairment later in life than those with a history of normotensive pregnancy. Furthermore, the pattern of cognitive changes is consistent with that observed with vascular disease/white matter pathology.


Asunto(s)
Disfunción Cognitiva/etiología , Preeclampsia/fisiopatología , Afecto , Anciano , Ansiedad , Disfunción Cognitiva/epidemiología , Depresión , Femenino , Humanos , Hipertensión/fisiopatología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Embarazo , Autoinforme
18.
J Bacteriol ; 198(12): 1725-1734, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27044629

RESUMEN

UNLABELLED: The Yersinia enterocolitica Ysa type III secretion system (T3SS) is associated with intracellular survival, and, like other characterized T3SSs, it is tightly controlled. Expression of the ysa genes is only detected following growth at low temperatures (26°C) and in high concentrations of sodium chloride (290 mM) in the medium. The YsrSTR phosphorelay (PR) system is required for ysa expression and likely responds to NaCl. During our investigations into the Ysr PR system, we discovered that genes YE3578 and YE3579 are remarkably similar to ysrR and ysrS, respectively, and are probably a consequence of a gene duplication event. The amino acid differences between YE3578 and ysrR are primarily clustered into two short regions. The differences between YE3579 and ysrS are nearly all located in the periplasmic sensing domain; the cytoplasmic domains are 98% identical. We investigated whether these paralogs were capable of activating ysa gene expression. We found that the sensor paralog, named DygS, is capable of compensating for loss of ysrS, but the response regulator paralog, DygR, cannot complement a ysrR gene deletion. In addition, YsrR, but not DygR, interacts with the histidine phosphorelay protein YsrT. Thus, DygS likely activates ysa gene expression in response to a signal other than NaCl and provides an example of a phosphorelay system in which two sensor kinases feed into the same regulatory pathway. IMPORTANCE: All organisms need mechanisms to promote survival in changing environments. Prokaryotic phosphorelay systems are minimally comprised of a histidine kinase (HK) that senses an extracellular stimulus and a response regulator (RR) but can contain three or more proteins. Through gene duplication, a unique hybrid HK was created. We show that, while the hybrid appears to retain all of the phosphorelay functions, it responds to a different signal than the original. Both HKs transmit the signal to the same RR, which activates a promoter that transcribes a set of genes encoding a type III secretion system (T3SS) whose function is not yet evident. The significance of this work lies in finding that two HKs regulate this T3SS, highlighting its importance.


Asunto(s)
Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Proteínas Quinasas/metabolismo , Sistemas de Secreción Tipo III/genética , Yersiniosis/microbiología , Yersinia enterocolitica/enzimología , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Humanos , Datos de Secuencia Molecular , Operón , Unión Proteica , Proteínas Quinasas/química , Proteínas Quinasas/genética , Alineación de Secuencia , Sistemas de Secreción Tipo III/metabolismo , Yersinia enterocolitica/química , Yersinia enterocolitica/genética , Yersinia enterocolitica/metabolismo
19.
Physiol Genomics ; 48(1): 33-41, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26508701

RESUMEN

Prior to the initiation of menopausal hormone treatment (MHT), genetic variations in the innate immunity pathway were found to be associated with carotid artery intima-medial thickness (CIMT) and coronary arterial calcification (CAC) in women (n = 606) enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Whether MHT might affect these associations is unknown. The association of treatment outcomes with variation in the same 764 candidate genes was evaluated in the same KEEPS participants 4 yr after randomization to either oral conjugated equine estrogens (0.45 mg/day), transdermal 17ß-estradiol (50 µg/day), each with progesterone (200 mg/day) for 12 days each month, or placebo pills and patch. Twenty SNPs within the innate immunity pathway most related with CIMT after 4 yr were not among those associated with CIMT prior to MHT. In 403 women who completed the study in their assigned treatment group, single nucleotide polymorphisms (SNPs) within the innate immunity pathway were found to alter the treatment effect on 4 yr change in CIMT (i.e., significant interaction between treatment and genetic variation in the innate immunity pathway; P < 0.001). No SNPs by treatment effects were observed with changes of CAC >5 Agatston units after 4 yr. Results of this study suggest that hormonal status may interact with genetic variants to influence cardiovascular phenotypes, specifically, the pharmacogenomic effects within the innate immunity pathway for CIMT.


Asunto(s)
Calcinosis/genética , Arterias Carótidas/patología , Grosor Intima-Media Carotídeo , Vasos Coronarios/patología , Estrógenos/farmacología , Animales , Arterias Carótidas/efectos de los fármacos , Intervalos de Confianza , Vasos Coronarios/efectos de los fármacos , Femenino , Estudios de Asociación Genética , Caballos , Humanos , Inmunidad Innata/genética , Farmacogenética , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Factores de Tiempo
20.
Physiol Genomics ; 48(1): 12-20, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26534935

RESUMEN

Nonobstructive coronary artery disease (CAD) in women is associated with adverse cardiovascular (CV) outcomes; however, information regarding genetic variants that predispose women to nonobstructive CAD is lacking. Women from the Women's Ischemia Syndrome Evaluation (WISE) Study and the St. James Women Take Heart (WTH) Study were genotyped with the Cardio-MetaboChip. WISE enrolled women with symptoms and signs of ischemia referred for coronary angiography; WTH enrolled asymptomatic, community-based women without heart disease. Analyses were conducted with a case (WISE)--control (WTH) design and multivariate logistic regression models to investigate genetic variation associated with likelihood of nonobstructive CAD. One genetic marker, single nucleotide polymorphism (SNP) rs2301753 on chromosome 6 in RNF39, achieved chip-wide significance for nonobstructive CAD (P < 9.5 × 10(-7)). After adjusting for baseline characteristics, we found no variants achieved chip-wide significance. However, SNP rs2301753 on chromosome 6 in RNF39 was associated with reduced likelihood of nonobstructive CAD [odds ratio (OR) 0.42 and 95% confidence interval (CI) of 0.29 to 0.68], at a nominal level of P = 5.6 × 10(-6), while SNP rs12818945 in the ATP2B1 locus on chromosome 12 was associated with increased odds for nonobstructive CAD (OR 2.38 and 95% CI of 1.63 to 3.45) and nominal P = 5.8 × 10(-6). The functions of RNF39 and ATP2B1 raise the possibility that genes involved in cardio-dysfunction may contribute to nonobstructive CAD in Caucasian women and may provide insights into novel approaches for therapy and prevention. If replicated, incorporation of these genetic variants into diagnostic evaluation may identify women at high risk for nonobstructive CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Estudios de Asociación Genética , Sitios Genéticos , Predisposición Genética a la Enfermedad , Población Blanca/genética , Presión Sanguínea , Índice de Masa Corporal , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/fisiopatología , Demografía , Diástole , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , ATPasas Transportadoras de Calcio de la Membrana Plasmática/genética , Polimorfismo de Nucleótido Simple/genética , Análisis de Componente Principal
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