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1.
Ann Vasc Surg ; 108: 76-83, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38942368

RESUMEN

BACKGROUND: Low wall shear stress (WSS) is predictive of aortic aneurysm growth and rupture. Yet, estimating WSS in a clinical setting is impractical, whereas measuring aneurysm geometry is feasible. This study investigates the association between saccular aneurysm geometry of the infrarenal aorta and WSS. METHODS: Starting with a nonaneurysmal, patient-specific, computational fluid dynamics model of the aorta, saccular aneurysms of varying geometry were created by incrementally increasing the neck width and sac depth from 1 cm to 4 cm. The aspect ratio (the ratio between sac depth and neck width) varied between 0.25 and 4. The peak WSS, time-averaged WSS (TAWSS), and oscillatory shear index (OSI) were measured within the aneurysm sac. RESULTS: Decreasing the neck width from 4 cm to 1 cm decreased the peak WSS by 69% and the TAWSS by 83%. Increasing the sac depth from 1 cm to 4 cm decreased the peak WSS by 55% and the OSI by 37%. The aspect ratio was negatively correlated to peak WSS (Rs -0.85; P < 0.001). CONCLUSIONS: In saccular aneurysms of the infrarenal aorta, a smaller neck width, deeper aneurysm sac, and larger aspect ratio are associated with lower peak WSS.


Asunto(s)
Aorta Abdominal , Aneurisma de la Aorta Abdominal , Modelos Cardiovasculares , Modelación Específica para el Paciente , Flujo Sanguíneo Regional , Estrés Mecánico , Humanos , Aneurisma de la Aorta Abdominal/fisiopatología , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/fisiopatología , Aorta Abdominal/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Velocidad del Flujo Sanguíneo , Aortografía , Simulación por Computador , Factores de Tiempo , Hemodinámica , Masculino , Hidrodinámica
2.
Am J Med Genet A ; 191(9): 2337-2343, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37435845

RESUMEN

Two children are presented who have a distinct syndrome of multiple buccolingual frenula, a stiff and short fifth finger with small nails, a hypothalamic hamartoma, mild to moderate neurological impairment, and mild endocrinological symptoms. No variant assessed to be pathogenic or likely pathogenic was detected in the GLI3 gene in either child. This syndrome appears to be distinct from the inherited Pallister-Hall syndrome associated with GLI3 variants, which is characterized by hypothalamic hamartoma, mesoaxial polydactyly, and other anomalies. In the individuals described here, manifestations outside of the central nervous system were milder and the mesoaxial polydactyly, which is common in individuals with Pallister-Hall syndrome, was absent. Instead, these children had multiple buccolingual frenula together with the unusual appearance of the fifth digit. It remains unclear whether these two individuals represent a separate nosologic entity or if they represent a milder manifestation of one of the more severe syndromes associated with a hypothalamic hamartoma.


Asunto(s)
Hamartoma , Enfermedades Hipotalámicas , Síndrome de Pallister-Hall , Polidactilia , Niño , Humanos , Síndrome de Pallister-Hall/diagnóstico , Síndrome de Pallister-Hall/genética , Hamartoma/diagnóstico , Hamartoma/genética , Hamartoma/patología , Enfermedades Hipotalámicas/diagnóstico , Enfermedades Hipotalámicas/genética , Enfermedades Hipotalámicas/patología , Polidactilia/genética
3.
Eur J Pediatr ; 182(6): 2903-2911, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37059961

RESUMEN

Current American Academy of Pediatrics (AAP) Guidelines recommend monitoring thyroid function in infants with Down syndrome (DS) at birth, 6 and 12 months, and annually thereafter. This study aimed to determine whether these guidelines are optimal for early diagnosis and treatment of (subclinical) hypothyroidism. Enrolled infants with DS less than age 7 months, born at ≥ 30 weeks gestation to monitor thyroid function test (TFT). A filter paper (FP) blood sample was analyzed for TSH and total T4 at ages 2 and 4 weeks and monthly thereafter until 12 months. Subjects with abnormal FP sample and confirmatory serum TFT for hypothyroidism promptly started treatment. Subjects with thyroid dysfunction identified had thyroid antibodies measured at diagnosis and 12 months. Descriptive statistics determined average time to diagnosis of abnormal TFT. Sixteen (30%) of 54 subjects were diagnosed with a thyroid disorder, the majority with subclinical hypothyroidism (SH) and 1 with hyperthyroidism. Diagnosis occurred in 6 (11%), 9 (17%), and 12 (22.2%) infants in the first 30, 60, and 90 days of life (DOL), respectively. Eight infants had an abnormal NBS and half were diagnosed with a thyroid disorder by DOL 8 and the remainder prior to 4 months. Among subjects with a normal NBS, four were diagnosed at a mean of 104 days and three at a mean of 101 days prior to the 6-month and 12-month routine screens, respectively.  Conclusion: Based on current AAP guidelines, thyroid disorder diagnosis would have been delayed in nearly 20% of the subjects. An additional TFT screen at 1 and 3 months can lead to earlier diagnosis and treatment. What is Known: • Current American Academy of Pediatrics (AAP) Guidelines recommend thyroid function tests (TFT) in infants with Down syndrome (DS) at birth and 6 and 12 months. • Peer- reviewed retrospective studies report an increased incidence of hypothyroidism in infants with DS undetected by the newborn screen (NBS) and prior to 6 months. What is New: • This prospective study monitored TFT in infants with DS at age 2 weeks and monthly throughout the first year of life. • The findings in this study support additional TFT screens at 1 and 3 months in infants with DS.


Asunto(s)
Hipotiroidismo Congénito , Síndrome de Down , Hipotiroidismo , Enfermedades de la Tiroides , Recién Nacido , Lactante , Humanos , Niño , Síndrome de Down/complicaciones , Síndrome de Down/diagnóstico , Estudios Prospectivos , Estudios Retrospectivos , Hipotiroidismo/complicaciones , Hipotiroidismo/diagnóstico , Enfermedades de la Tiroides/complicaciones , Enfermedades de la Tiroides/diagnóstico , Pruebas de Función de la Tiroides , Tirotropina , Tiroxina , Hipotiroidismo Congénito/diagnóstico
4.
Hum Reprod ; 37(4): 848-858, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35038334

RESUMEN

STUDY QUESTION: Are peripubertal blood lead levels (BLLs) associated with semen parameters and serum reproductive hormones among young Russian men? SUMMARY ANSWER: We observed a suggestion of lower ejaculate volume with higher peripubertal BLL but no associations of BLLs with reproductive hormones measured throughout adolescence or with other sperm parameters measured at adulthood. WHAT IS KNOWN ALREADY: Lead is a known reproductive toxicant and endocrine disruptor. Previous literature has shown associations between high lead exposure and poorer semen quality both in occupationally and environmentally exposed men. However, to our knowledge, no longitudinal studies have explored the association of childhood lead exposure with semen parameters and reproductive hormones in young men. STUDY DESIGN, SIZE, DURATION: The Russian Children's Study is a prospective cohort study that enrolled 516 boys at age 8-9 years in 2003-2005 and followed them annually for 10 years. BLLs were measured at entry and lifestyle and health questionnaires were completed. Reproductive hormones were measured in blood samples collected every 2 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Among the 516 boys enrolled, 481 had BLLs measured at entry. Of these, 453 had at least one measurement of serum testosterone, follicle stimulating hormone (FSH) or luteinizing hormone (LH) (median = 5 samples per boy) and 223 had semen samples collected ∼10 years after enrolment. Semen assessment included ejaculated volume, sperm concentration, progressive motility and total sperm count, and parameters were categorized using published andrology standards for low semen quality based on sperm count and motility. Linear mixed models were used to examine the associations of log-transformed BLLs (and BLL categories) with reproductive hormones and semen parameters, adjusting for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 223 young men with peripubertal BLLs and at least one semen sample (total samples = 438), the median (interquartile range) BLL was 3 (2, 5) µg/dl and 27% had BLL ≥5 µg/dl. Overall, 49% of the semen samples fell below reference levels for sperm count and/or motility. Men with peripubertal BLL ≥5 µg/dl had significantly lower ejaculated volume than those with BLL <5 µg/dl (mean = 2.42 vs 2.89 ml, P = 0.02), but this difference was attenuated in adjusted models (mean = 2.60 vs 2.83 ml, P = 0.25). No associations were observed between BLL measured at age 8-9 years and reproductive hormone levels or sperm parameters, including sperm concentration, total count, progressive motility and total progressive motile sperm count, or with the probability of having low semen quality based on sperm count/motility. LIMITATIONS, REASONS FOR CAUTION: Only a subset of the original cohort participated in the semen quality portion of the study, although inverse probability weighting was used to account for possible selection bias. BLLs were only measured at a single time in peripuberty, and other exposure time periods, including later or longer-term childhood exposure, may be more predictive of semen quality. The young men were also exposed to other chemical contaminants before and during pubertal development. WIDER IMPLICATIONS OF THE FINDINGS: While semen volume often receives less attention than other sperm parameters, it is an important component of male fertility. Additional prospective studies covering different exposure windows and including other seminal plasma biomarkers are warranted to explore our finding of potentially lower ejaculated volume with higher BLLs and to confirm the lack of associations for other semen parameters among youth exposed to environmental BLLs. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided through grants R01ES0014370 and P30ES000002 from the National Institute of Environmental Health Sciences, grant R82943701 from the U.S. Environmental Protection Agency, and grant 18-15-00202 from the Russian Science Foundation (O.S and Y.D.). All authors report no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Plomo , Semen , Adolescente , Adulto , Niño , Estudios de Cohortes , Humanos , Hormona Luteinizante , Masculino , Estudios Prospectivos , Análisis de Semen , Recuento de Espermatozoides , Motilidad Espermática
5.
Environ Res ; 212(Pt A): 113218, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35390299

RESUMEN

BACKGROUND: Although phthalate exposures have been associated with adverse effects on male reproductive health, few studies have explored longitudinal associations with male pubertal development. OBJECTIVES: We examined the association of prepubertal urinary concentrations of phthalate metabolites with age at pubertal onset in a prospective cohort of Russian boys. METHODS: At enrollment at ages 8-9 years, medical history, dietary, and demographic information was collected. At entry and annually, physical examinations and pubertal staging [Genitalia (G), Pubarche (P), and testicular volume (TV, in ml)] were conducted and spot urines were collected. Prepubertal urine samples (defined as either TV = 1, 2 and G = 1, 2 or TV = 3 and G = 1) were pooled for each boy and phthalate metabolite concentrations were quantified using isotope dilution LC-MS/MS at Moscow State University. We measured 15 metabolites including those from anti-androgenic parent phthalates (AAPs) such as di (2-ethylhexyl) (DEHP) and di-isononyl (DiNP) phthalates as well as monobenzyl (MBzP), mono-n-butyl (MnBP), and mono-isobutyl (MiBP) metabolites. We calculated the molar sums of DEHP (∑DEHP), DiNP (∑DiNP), and AAP (∑AAP) metabolites. Separate interval-censored models were used to assess associations of quartiles of prepubertal phthalate metabolites with each pubertal onset indicator, G2+, P2+ and TV > 3 mL, adjusted for covariates and urine specific gravity. RESULTS: 304 boys had 752 prepubertal urine samples (median 2, range: 1-6) for pooling. In adjusted models, higher urinary AAPs were consistently associated with later pubertal onset (P2) with mean shifts ranging from 8.4 to 14.2 months for the highest versus lowest quartiles. Significantly later onset for G2 and TV > 3 mL was observed for higher versus lower quartiles of MiBP, MBzP, ∑DEHP and ∑DiNP. CONCLUSIONS: On average, boys with higher concentrations of prepubertal urinary AAPs had later pubertal onset by six months to over a year. The impact of AAPs on timing of male puberty may be attributable to disruption of androgen-dependent biological pathways.


Asunto(s)
Dietilhexil Ftalato , Contaminantes Ambientales , Ácidos Ftálicos , Antagonistas de Andrógenos , Niño , Cromatografía Liquida , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/orina , Humanos , Masculino , Ácidos Ftálicos/orina , Estudios Prospectivos , Espectrometría de Masas en Tándem
6.
J Biol Chem ; 293(28): 10884-10894, 2018 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-29773653

RESUMEN

Protein arginine methyltransferase 5 (PRMT5) regulates gene expression either transcriptionally by symmetric dimethylation of arginine residues on histones H4R3, H3R8, and H2AR3 or at the posttranslational level by methylation of nonhistone target proteins. Although emerging evidence suggests that PRMT5 functions as an oncogene, its role in metabolic diseases is not well-defined. We investigated the role of PRMT5 in promoting high-fat-induced hepatic steatosis. A high-fat diet up-regulated PRMT5 levels in the liver but not in other metabolically relevant tissues such as skeletal muscle or white and brown adipose tissue. This was associated with repression of master transcription regulators involved in mitochondrial biogenesis. In contrast, lentiviral short hairpin RNA-mediated reduction of PRMT5 significantly decreased phosphatidylinositol 3-kinase/AKT signaling in mouse AML12 liver cells. PRMT5 knockdown or knockout decreased basal AKT phosphorylation but boosted the expression of peroxisome proliferator-activated receptor α (PPARα) and PGC-1α with a concomitant increase in mitochondrial biogenesis. Moreover, by overexpressing an exogenous WT or enzyme-dead mutant PRMT5 or by inhibiting PRMT5 enzymatic activity with a small-molecule inhibitor, we demonstrated that the enzymatic activity of PRMT5 is required for regulation of PPARα and PGC-1α expression and mitochondrial biogenesis. Our results suggest that targeting PRMT5 may have therapeutic potential for the treatment of fatty liver.


Asunto(s)
Hígado/citología , Mitocondrias/fisiología , Biogénesis de Organelos , PPAR alfa/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Animales , Dieta Alta en Grasa , Regulación de la Expresión Génica , Hígado/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , PPAR alfa/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Transducción de Señal
7.
Health Promot Pract ; 19(1_suppl): 24S-33S, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30176774

RESUMEN

Racial equity is closely linked to principles of fairness and justice. It is distinct from the concept of racial equality. Community engaged strategies aimed at creating racial equity have generated effective ways to dismantle structural racism-the racialized policies and practices that have shaped economic and social institutions in the United States throughout its history. In crafting the Food & Fitness Initiative, the W.K. Kellogg Foundation made advancing racial equity a top priority. By doing so, it encouraged the community partnerships funded under the initiative to apply theories of expanding equity to real-world situations in order to reduce racial disparities in their neighborhoods. This article reviews the methods that were employed over the course of the initiative to support the partnerships with their efforts. It highlights three key components: (1) being intentional about maintaining a focus on racial equity, (2) concentrating on changing policies and systems, and (3) consistently incorporating meaningful and authentic community engagement into the work. The importance of making the concept of equity concrete and measurable is explored. Furthermore, the article discusses strategies that strengthened the capacity of the partnerships to navigate the policy-making process and to build leadership and shift power to community residents. The article concludes by detailing measures that could guide future efforts to make racial equity a priority and emphasizes that doing so is crucial given the rapid demographic shifts underway across the country.


Asunto(s)
Participación de la Comunidad , Relaciones Comunidad-Institución , Promoción de la Salud/métodos , Promoción de la Salud/organización & administración , Racismo/prevención & control , Etnicidad , Ejercicio Físico , Alimentos , Fundaciones , Disparidades en el Estado de Salud , Humanos , Liderazgo , Formulación de Políticas , Estados Unidos
8.
Annu Rev Public Health ; 37: 185-204, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26789383

RESUMEN

To improve health in the twenty-first century, to promote both access to and quality of health care services and delivery, and to address significant health disparities, legal and policy approaches, specifically those focused on civil rights, could be used more intentionally and strategically. This review describes how civil rights laws, and their implementation and enforcement, help to encourage health in the United States, and it provides examples for peers around the world. The review uses a broad lens to define health for both classes of individuals and their communities--places where people live, learn, work, and play. Suggestions are offered for improving health and equity broadly, especially within societal groups and marginalized populations. These recommendations include multisectorial approaches that focus on the social determinants of health.


Asunto(s)
Derechos Civiles/legislación & jurisprudencia , Política de Salud , Disparidades en el Estado de Salud , Barreras de Comunicación , Cultura , Planificación en Desastres/organización & administración , Reforma de la Atención de Salud/organización & administración , Accesibilidad a los Servicios de Salud/organización & administración , Humanos , Programas de Inmunización/organización & administración , Lenguaje , Vigilancia en Salud Pública/métodos , Calidad de la Atención de Salud/organización & administración , Determinantes Sociales de la Salud/legislación & jurisprudencia , Justicia Social , Factores Socioeconómicos , Estados Unidos/epidemiología , Violencia/legislación & jurisprudencia , Violencia/prevención & control
9.
BMC Pregnancy Childbirth ; 15: 71, 2015 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-25885002

RESUMEN

BACKGROUND: Maternal and offspring immediate and long-term health are affected by pregnancy weight gain and maternal weight. This study was designed to determine feasibility of: 1) recruiting a socio-economically and racially/ethnically diverse sample of pregnant women into a longitudinal observational study, including consenting the women for serial biologic specimen evaluations; 2) implementing comprehensive assessments (including biologic, anthropometric, behavioral, cognitive/psychosocial and socio-demographic, and cultural measures) at multiple time points over the study period, including collecting biologic specimens at planned and unplanned pregnancy delivery times; and 3) retaining the sample for one year into the postpartum period. Additionally, the study will provide preliminary data of associations among hypothesized predictors, mediators and moderators of pregnancy and post-partum maternal and infant weight trajectories. The study was conceptualized under a Biopsychosocial Model using a lifespan approach. Study protocol and baseline characteristics are described. METHODS/DESIGN: We sought to recruit a sample of 100 healthy women age 18-45 years, between 28-34 weeks gestation, with singleton pregnancies, enrolled in care prior to 17 weeks gestation. Women provide written consent for face-to-face (medical history, anthropometrics, biologic specimens), and paper-and-pencil assessments, at five time points: baseline (third trimester), delivery-associated, and 6-weeks, 3-months and 6-months postpartum. Additional telephone-based assessments (diet, physical activity and breastfeeding) administered baseline and three-months postpartum. Infant weights are collected until 1-year of life. We seek to retain 80% of participants at six-months postpartum and 80% of offspring at 12-months. 110 women were recruited. Sample characteristics include: mean age 28.3 years, BMI 25.7 kg/m(2), and gestational age at baseline visit of 32.5 weeks. One-third of cohort was non-white, over a quarter were Latina, and almost a quarter were non-US born. The cohort majority was multigravida, had graduated high school and/or had higher levels of education, and worked outside the home. DISCUSSION: Documentation of study feasibility and preliminary data for theory-driven hypothesis of maternal and child factors associated with weight trajectories will support future large scale longitudinal studies of risk and protective factors for maternal and child health. This research will also inform intervention targets facilitating healthy maternal and child weight.


Asunto(s)
Obesidad , Periodo Posparto , Complicaciones del Embarazo , Aumento de Peso , Adulto , Antropometría/métodos , Demografía , Femenino , Edad Gestacional , Humanos , Lactante , Obesidad/epidemiología , Obesidad/etiología , Periodo Posparto/fisiología , Periodo Posparto/psicología , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Psicología , Proyectos de Investigación , Factores de Riesgo , Factores Socioeconómicos , Estados Unidos
10.
Am J Epidemiol ; 180(9): 909-19, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25255811

RESUMEN

Organochlorine pesticides (OCPs) have been linked to adult metabolic disorders; however, few studies have examined these associations in childhood. We prospectively evaluated the associations of baseline serum OCPs (hexachlorobenzene, ß-hexachlorocyclohexane, and p,p'-dichlorodiphenyldichloroethylene) in Russian boys with subsequent repeated measurements of serum glucose, insulin, lipids, leptin, and calculated homeostatic model assessment of insulin resistance (IR). During 2003-2005, we enrolled 499 boys aged 8-9 years in a prospective cohort; 318 had baseline serum OCPs and serum biomarkers measured at ages 10-13 years. Multivariable generalized estimating equation and mediation regression models were used to examine associations and direct and indirect (via body mass index (BMI) (weight (kg)/height (m)(2))) effects of prepubertal OCP tertiles and quintiles with biomarkers. In multivariable models, higher p,p'-dichlorodiphenyldichloroethylene (quintile 5 vs. quintile 1) was associated with lower leptin, with relative mean decreases of 61.8% (95% confidence interval: 48.4%, 71.7%) in models unadjusted for BMI and 22.2% (95% confidence interval: 7.1%, 34.9%) in models adjusted for BMI; the direct effect of p,p'-dichlorodiphenyldichloroethylene on leptin accounted for 27% of the total effect. IR prevalence was 6.6% at ages 12-13 years. Higher hexachlorobenzene (tertile 3 vs. tertile 1) was associated with higher odds of IR in models adjusted for BMI (odds ratio = 4.37, 95% confidence interval: 1.44, 13.28). These results suggest that childhood OCPs may be associated with IR and lower leptin.


Asunto(s)
Hidrocarburos Clorados/sangre , Resistencia a la Insulina , Síndrome Metabólico/sangre , Plaguicidas/sangre , Adolescente , Biomarcadores/sangre , Glucemia/análisis , Niño , Colesterol/sangre , Humanos , Insulina/sangre , Leptina/sangre , Masculino , Estudios Prospectivos , Análisis de Regresión , Triglicéridos/sangre
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