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1.
Nature ; 603(7902): 631-636, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35322249

RESUMO

Metastable phases-kinetically favoured structures-are ubiquitous in nature1,2. Rather than forming thermodynamically stable ground-state structures, crystals grown from high-energy precursors often initially adopt metastable structures depending on the initial conditions, such as temperature, pressure or crystal size1,3,4. As the crystals grow further, they typically undergo a series of transformations from metastable phases to lower-energy and ultimately energetically stable phases1,3,4. Metastable phases sometimes exhibit superior physicochemical properties and, hence, the discovery and synthesis of new metastable phases are promising avenues for innovations in materials science1,5. However, the search for metastable materials has mainly been heuristic, performed on the basis of experiences, intuition or even speculative predictions, namely 'rules of thumb'. This limitation necessitates the advent of a new paradigm to discover new metastable phases based on rational design. Such a design rule is embodied in the discovery of a metastable hexagonal close-packed (hcp) palladium hydride (PdHx) synthesized in a liquid cell transmission electron microscope. The metastable hcp structure is stabilized through a unique interplay between the precursor concentrations in the solution: a sufficient supply of hydrogen (H) favours the hcp structure on the subnanometre scale, and an insufficient supply of Pd inhibits further growth and subsequent transition towards the thermodynamically stable face-centred cubic structure. These findings provide thermodynamic insights into metastability engineering strategies that can be deployed to discover new metastable phases.

2.
Nature ; 577(7790): 359-363, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942056

RESUMO

The impact of topological defects associated with grain boundaries (GB defects) on the electrical, optical, magnetic, mechanical and chemical properties of nanocrystalline materials1,2 is well known. However, elucidating this influence experimentally is difficult because grains typically exhibit a large range of sizes, shapes and random relative orientations3-5. Here we demonstrate that precise control of the heteroepitaxy of colloidal polyhedral nanocrystals enables ordered grain growth and can thereby produce material samples with uniform GB defects. We illustrate our approach with a multigrain nanocrystal comprising a Co3O4 nanocube core that carries a Mn3O4 shell on each facet. The individual shells are symmetry-related interconnected grains6, and the large geometric misfit between adjacent tetragonal Mn3O4 grains results in tilt boundaries at the sharp edges of the Co3O4 nanocube core that join via disclinations. We identify four design principles that govern the production of these highly ordered multigrain nanostructures. First, the shape of the substrate nanocrystal must guide the crystallographic orientation of the overgrowth phase7. Second, the size of the substrate must be smaller than the characteristic distance between the dislocations. Third, the incompatible symmetry between the overgrowth phase and the substrate increases the geometric misfit strain between the grains. Fourth, for GB formation under near-equilibrium conditions, the surface energy of the shell needs to be balanced by the increasing elastic energy through ligand passivation8-10. With these principles, we can produce a range of multigrain nanocrystals containing distinct GB defects.

3.
J Am Chem Soc ; 146(27): 18586-18591, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38949127

RESUMO

Intercalation of hydrogen into the palladium atomic layers during the growth of Pd nanoparticles can lead to the synthesis of unique palladium hydride phases. Here, we discover an unusual nonfcc palladium hydride nanoparticle, a structure that is not face-centered cubic (fcc), formed through coreduction of water molecules and Pd ions in solution. Crystal structure determination based on atomic electron tomography points to potential triclinic unit cells, indicating the presence of more than one nonfcc phase, with some of those being a stack of loosened and distorted close-packed layer of atoms. The probability of finding the nonfcc phase in single-crystalline particles varies depending on the number and distribution of contact area with other particles. Roughly half of the isolated and one side-coalesced single-crystal particles exhibit a nonfcc structure, while fcc dominates multiple side-coalesced single crystals as well as polycrystal particles. These observations suggest a coalescence-induced phase transition from a nonfcc to a stable fcc structure, due to the metastable nature of the nonfcc phases. While hydrogen is proven to be a key component for the synthesis of the nonfcc structure, there was limited formation of the unusual phase in a H2 gas bubbling system. Thus, electrochemical pathways can be promising for the in situ creation and study of unique metastable nanomaterials.

4.
BMC Infect Dis ; 24(Suppl 1): 194, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418989

RESUMO

BACKGROUND: Sexually transmitted infections (STIs) such as syphilis and HIV remain to be a significant public health issue worldwide. Dual rapid point-of-care tests (POCTs) have shown promise for detecting antibodies to HIV and syphilis but have not been fully evaluated in the field. Our study supported the WHO ProSPeRo study on Sexually Transmitted Infection Point-of-Care Testing (STI POCT) by providing external quality assessment (EQA) for HIV and syphilis testing in reference laboratories and their associated clinical sites in seven countries. METHODS: HIV/syphilis serum liquid and dried tube specimen (DTS) panels were prepared by CDC. Liquid panels were distributed to the reference laboratories for three rounds of testing using commercially and locally available laboratory-based serological tests. DTS panels were sent to the clinical testing sites for 8 rounds of POC testing using the Abbott SD BIOLINE HIV/Syphilis Duo test (hereafter referred to as SD BIOLINE) and the Chembio Dual Path Platform (DPP) HIV-Syphilis assay. EQA panels were tested at CDC using the Rapid Plasma Reagin (RPR) test and the Treponema pallidum Particle Agglutination assay (TP-PA) for syphilis antibodies. Genetic Systems HIV-1/HIV-2 Plus O EIA, Geenius HIV Supplemental Assay and the Oraquick Advance HIV test were used to detect HIV antibodies in the EQA panels. Results from the reference laboratories and POCT sites were compared to those obtained at the CDC and a percentage agreement was calculated. RESULTS: Qualitative RPR and TP-PA performed at the reference laboratories demonstrated 95.4-100% agreement with CDC results while quantitative RPR and TP-PA tests demonstrated 87.7% and 89.2% agreement, respectively. A 93.8% concordance rate was observed for qualitative HIV testing in laboratories. EQA testing at clinical sites using dual tests showed 98.7% and 99.1% agreement for detection of HIV antibodies and eight out of 10 sites had > 95.8% agreement for syphilis testing. However, two clinical sites showed only 65.0-66.7% agreement for SD BIOLINE and 84.0-86.7% for DPP, respectively, for syphilis testing. CONCLUSIONS: Overall, laboratories demonstrated high EQA performance in this study. Both HIV/syphilis POCTs gave expected results in the clinic-based evaluations using DTS. However, testing errors were identified in a few testing sites suggesting the necessity for continuous training and monitoring the quality of POC testing.


Assuntos
Infecções por HIV , HIV-1 , Sífilis , Humanos , Treponema pallidum , Anticorpos Anti-HIV , Infecções por HIV/diagnóstico , Sensibilidade e Especificidade , Anticorpos Antibacterianos , Testes Imediatos , Sorodiagnóstico da Sífilis/métodos , HIV-2 , Organização Mundial da Saúde , Sistemas Automatizados de Assistência Junto ao Leito
5.
J Clin Microbiol ; 61(6): e0016823, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37219422

RESUMO

Automated nontreponemal rapid plasma reagin (RPR) tests were recently introduced in the United States for syphilis testing and limited performance data are available. In collaboration with the Association of Public Health Laboratories, three public health laboratories (PHL) were chosen through a competitive selection process to evaluate the performance of three FDA-cleared automated RPR test systems: BioPlex 2200 Syphilis Total & RPR assay (Bio-Rad Laboratories), AIX 1000 (Gold Standard Diagnostics), and ASI Evolution (Arlington Scientific). Panels prepared at the CDC included: a qualitative panel comprised of 734 syphilis reactive/nonreactive sera; a quantitative panel of 50 syphilis reactive sera (RPR titer 1:64 to 1:1,024); and a reproducibility panel of 15 nonreactive and reactive sera (RPR titer 1:1 to 1:64). Panels were shipped frozen to the PHL and tested on the automated RPR systems following manufacturers' instructions. Prior test results were blinded to all laboratories. When compared to manual RPR (Arlington Scientific) performed at the CDC as a reference test, the qualitative panel results demonstrated an overall concordance of 95.9% for AIX 1000, 94.6% for ASI Evolution, and 92.6% for Bioplex RPR; quantitative panel showed within range titer of 2-fold for 94% of specimens for AIX 1000, 68% for ASI Evolution, and 64% for BioPlex RPR, and the reproducibility testing panel demonstrated point estimates ranging from 69 to 95%. Automated RPR instruments could reduce turnaround time and minimize interpretation errors. However, additional evaluations with more specimens could assist laboratories with implementing automated RPR tests and understanding their limitations.


Assuntos
Sífilis , Humanos , Sífilis/diagnóstico , Reaginas , Reprodutibilidade dos Testes , Anticorpos Antibacterianos , Sorodiagnóstico da Sífilis/métodos , Treponema pallidum
6.
Sex Transm Infect ; 99(8): 513-519, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37648446

RESUMO

OBJECTIVES: To measure the effectiveness of chlamydia control strategies, we must estimate infection incidence over time. Available data, including survey-based infection prevalence and case reports, have limitations as proxies for infection incidence. We therefore developed a novel method for estimating chlamydial incidence. METHODS: We linked a susceptible infectious mathematical model to serodynamics data from the National Health and Nutritional Examination Survey, as well as to annual case reports. We created four iterations of this model, varying assumptions about how the method of infection clearance (via treatment seeking, routine screening or natural clearance) relates to long-term seropositivity. Using these models, we estimated annual infection incidence for women aged 18-24 and 25-37 years in 2014. To assess model plausibility, we also estimated natural clearance for the same groups. RESULTS: Of the four models we analysed, the model that best explained the empirical data was the one in which longer-lasting infections, natural clearance and symptomatic infections all increased the probability of long-term seroconversion. Using this model, we estimated 5910 (quartile (Q)1, 5330; Q3, 6500) incident infections per 100 000 women aged 18-24 years and 2790 (Q1, 2500; Q3, 3090) incident infections per 100 000 women aged 25-37 years in 2014. Furthermore, we estimated that natural clearance rates increased with age. CONCLUSIONS: Our method can be used to estimate the number of chlamydia infections each year, and thus whether infection incidence increases or decreases over time and after policy changes. Furthermore, our results suggest that clearance via medical intervention may lead to short-term or no seroconversion, and the duration of untreated chlamydial infection may vary with age, underlining the complexity of chlamydial infection dynamics.


Assuntos
Infecções por Chlamydia , Soropositividade para HIV , Humanos , Feminino , Prevalência , Estudos Soroepidemiológicos , Incidência , Chlamydia trachomatis , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/prevenção & controle
7.
MMWR Morb Mortal Wkly Rep ; 72(21): 574-578, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37227985

RESUMO

During May 10-December 31, 2022, a total of 29,980 confirmed and probable† U.S. monkeypox (mpox) cases were reported to CDC, predominantly in cisgender adult men reporting recent same-gender sexual partners (1). Urban-rural differences in health (2) and diagnosis of HIV (3,4) and other sexually transmitted infections (5) are well documented nationally. This report describes urban-rural differences in mpox incidence (cases per 100,000 population) among persons aged 15-64 years, by gender and race and ethnicity. Urbanicity was assessed using the 2013 National Center for Health Statistics (NCHS) Urban-Rural Classification Scheme for Counties (2). Substantial differences in incidence by urbanicity, gender, and race and ethnicity were observed; most (71.0%) cases occurred in persons residing in large central urban areas. Among the cases in large central urban areas, most (95.7%) were in cisgender men. The overall incidence of mpox in the United States was 13.5 per 100,000 persons aged 15-64 years and peaked in August in both urban and rural areas. Among cisgender men, incidence in rural areas was approximately 4% that in large central urban areas (risk ratio [RR] = 0.04). Among cisgender women, incidence in rural areas was approximately 11% that in large central urban areas (RR = 0.11). In both urban and rural areas, incidence among non-Hispanic Black or African American (Black) and Hispanic or Latino (Hispanic) persons was consistently higher than that among non-Hispanic White (White) persons; RRs between Black and White persons were highest in rural areas. Support and maintenance of mpox surveillance and prevention efforts including vaccinations should focus on urban areas with the highest incidence of mpox during the 2022 outbreak; however, surveillance and prevention efforts should include all genders, persons of color, and persons residing in both urban and rural areas who are at increased risk for mpox.


Assuntos
Mpox , Adulto , Feminino , Humanos , Masculino , Etnicidade , Hispânico ou Latino , Incidência , Mpox/epidemiologia , População Rural , Estados Unidos/epidemiologia , População Urbana , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Negro ou Afro-Americano , Brancos
8.
MMWR Morb Mortal Wkly Rep ; 72(23): 627-632, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37289660

RESUMO

More than 30,000 monkeypox (mpox) cases were reported in the United States during the 2022 multinational outbreak; cases disproportionately affected gay, bisexual, and other men who have sex with men (MSM). Substantial racial and ethnic disparities in incidence were also reported (1). The national mpox vaccination strategy* emphasizes that efforts to administer the JYNNEOS mpox vaccine should be focused among the populations at elevated risk for exposure to mpox (2). During May 2022-April 2023, a total of 748,329 first JYNNEOS vaccine doses (of the two recommended) were administered in the United States.† During the initial months of the outbreak, lower vaccination coverage rates among racial and ethnic minority groups were reported (1,3); however, after implementation of initiatives developed to expand access to mpox vaccination,§ coverage among racial and ethnic minority groups increased (1,4). A shortfall analysis was conducted to examine whether the increase in mpox vaccination coverage was equitable across all racial and ethnic groups (5). Shortfall was defined as the percentage of the vaccine-eligible population that did not receive the vaccine (i.e., 100% minus the percentage of the eligible population that did receive a first dose). Monthly mpox vaccination shortfalls were calculated and were stratified by race and ethnicity; monthly percent reductions in shortfall were also calculated compared with the preceding month's shortfall (6). The mpox vaccination shortfall decreased among all racial and ethnic groups during May 2022-April 2023; however, based on analysis of vaccine administration data with race and ethnicity reported, 66.0% of vaccine-eligible persons remained unvaccinated at the end of this period. The shortfall was largest among non-Hispanic Black or African American (Black) (77.9%) and non-Hispanic American Indian or Alaska Native (AI/AN) (74.5%) persons, followed by non-Hispanic White (White) (66.6%) and Hispanic or Latino (Hispanic) (63.0%) persons, and was lowest among non-Hispanic Asian (Asian) (38.5%) and non-Hispanic Native Hawaiian and other Pacific Islander (NH/OPI) (43.7%) persons. The largest percentage decreases in the shortfall were achieved during August (17.7%) and September (8.5%). However, during these months, smaller percentage decreases were achieved among Black persons (12.2% and 4.9%, respectively), highlighting the need for a focus on equity for the entirety of a public health response. Achieving equitable progress in JYNNEOS vaccination coverage will require substantial decreases in shortfalls among Black and AI/AN persons.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Vacina Antivariólica , Masculino , Humanos , Estados Unidos/epidemiologia , Etnicidade , Homossexualidade Masculina , Cobertura Vacinal , Grupos Minoritários , Vacinação
9.
MMWR Morb Mortal Wkly Rep ; 72(15): 398-403, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37053122

RESUMO

As of December 31, 2022, a total of 29,939 monkeypox (mpox) cases* had been reported in the United States, 93.3% of which occurred in adult males. During May 10-December 31, 2022, 723,112 persons in the United States received the first dose in a 2-dose mpox (JYNNEOS)† vaccination series; 89.7% of these doses were administered to males (1). The current mpox outbreak has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) and racial and ethnic minority groups (1,2). To examine racial and ethnic disparities in mpox incidence and vaccination rates, rate ratios (RRs) for incidence and vaccination rates and vaccination-to-case ratios were calculated, and trends in these measures were assessed among males aged ≥18 years (males) (3). Incidence in males in all racial and ethnic minority groups except non-Hispanic Asian (Asian) males was higher than that among non-Hispanic White (White) males. At the peak of the outbreak in August 2022, incidences among non-Hispanic Black or African American (Black) and Hispanic or Latino (Hispanic) males were higher than incidence among White males (RR = 6.9 and 4.1, respectively). Overall, vaccination rates were higher among males in racial and ethnic minority groups than among White males. However, the vaccination-to-case ratio was lower among Black (8.8) and Hispanic (16.2) males than among White males (42.5) during the full analytic period, indicating that vaccination rates among Black and Hispanic males were not proportionate to the elevated incidence rates (i.e., these groups had a higher unmet vaccination need). Efforts to increase vaccination among Black and Hispanic males might have resulted in the observed relative increased rates of vaccination; however, these increases were only partially successful in reducing overall incidence disparities. Continued implementation of equity-based vaccination strategies is needed to further increase vaccination rates and reduce the incidence of mpox among all racial and ethnic groups. Recent modeling data (4) showing that, based on current vaccination coverage levels, many U.S. jurisdictions are vulnerable to resurgent mpox outbreaks, underscore the need for continued vaccination efforts, particularly among racial and ethnic minority groups.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Masculino , Adulto , Humanos , Estados Unidos/epidemiologia , Adolescente , Etnicidade , Homossexualidade Masculina , Grupos Minoritários , Vacinação , Brancos
10.
BMC Public Health ; 23(1): 948, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231395

RESUMO

BACKGROUND: Low body weight is associated with an increased risk of fractures. However, the effect of temporal changes in the low body weight status on the risk of fracture remains unknown. This study aimed to evaluate the relationships between temporal changes in low body weight status and the risk of fractures in adults over the age of 40 years. METHODS: This study included data on adults over 40 years old who underwent two biannual consecutive general health examinations between January 1, 2007 and December 31, 2009 extracted from the National Health Insurance Database, a large nationwide population database. Fracture cases in this cohort were monitored from the time of the last health examination to the end of the designated follow-up period (from January 1, 2010 to December 31, 2018) or the participant's death. Fractures were defined as any fracture resulting in hospitalization or outpatient treatment claim after the date of general health screening. The study population was then separated into four groups based on the temporal changes in low body weight status as follows: low body weight to low body weight (L-to-L), low body weight to non-low body weight (L-to-N), non-low body weight to low body weight (N-to-L), and non-low body weight to non-low body weight (N-to-N). The hazard ratios (HRs) for new fractures, depending on weight changes over time, were calculated using Cox proportional hazard analysis. RESULTS: Adults in the L-to-L, N-to-L, and L-to-N groups had a substantially increased risk of fractures after multivariate adjustment (HR, 1.165; 95% confidence interval [CI], 1.113-1.218; HR, 1.193; 95% CI, 1.131-1.259; and HR, 1.114; 95% CI, 1.050-1.183, respectively). Although the adjusted HR was greater in participants who changed into having a low body weight, followed by those with consistently low body weight, those with low body weight remained to have an elevated risk of fracture independent of weight fluctuation. Elderly men (aged over 65 years), high blood pressure, and chronic kidney disease were significantly associated with an increase in fractures (p < 0.05). CONCLUSION: Individuals aged over 40 years with low body weight, even after regaining normal weight, had an increased risk of fracture. Moreover, having a low body weight after having a normal body weight increased the risk of fractures the most, followed by those with consistently low body weight.


Assuntos
Hipertensão , Masculino , Idoso , Humanos , Adulto , Pessoa de Meia-Idade , Estudos de Coortes , Fatores de Risco , Modelos de Riscos Proporcionais , Magreza
11.
BMC Musculoskelet Disord ; 24(1): 586, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464374

RESUMO

BACKGROUND: Pyogenic spondylitis is a condition with low incidence that can lead to neurological sequelae and even life-threatening conditions. While conservative methods, including antibiotics and bracing, are considered the first-line treatment option for pyogenic spondylitis, it is important to identify patients who require early surgical intervention to prevent progressive neurologic deficits or deterioration of the systemic condition. Surgical treatment should be considered in patients with progressive neurologic deficits or deteriorating systemic condition. However, currently, there is a lack of treatment guidelines, particularly with respect to whether surgical treatment is necessary for pyogenic spondylitis. This study aims to analyze the radiological epidural abscess on MRI and clinical factors to predict the need for early surgical intervention in patients with pyogenic spondylitis and provide comprehensive insight into the necessity of early surgical intervention in these patients. METHODS: This study retrospectively reviewed 47 patients with pyogenic spondylitis including spondylodiscitis, vertebral osteomyelitis, epidural abscess, and/or psoas abscess. All patients received plain radiographs, and a gadolinium-enhanced magnetic resonance imaging (MRI) scan. All patients have either tissue biopsies and/or blood cultures for the diagnosis of a pathogen. Demographic data, laboratory tests, and clinical predisposing factors including comorbidities and concurrent other infections were analyzed. RESULTS: We analyzed 47 patients, 25 of whom were female, with a mean age of 70,7 years. MRI revealed that 26 of 47 patients had epidural abscesses. The surgical group had a significantly higher incidence of epidural abscess than the non-surgical group (p = 0.001). In addition, both CRP and initial body temperature (BT) were substantially higher in the surgical group compared to the non-surgical group. There was no significant difference between the surgical group and the non-surgical group in terms of age, gender, comorbidities, and concurrent infectious disorders, as well as the number of affected segments and affected spine levels. However, the surgical group had lengthier hospital stays and received more antibiotics. CONCLUSION: The presence of an epidural abscess on MRI should be regarded crucial in the decision-making process for early surgical treatment in patients with pyogenic spondylitis in order to improve clinical outcomes.


Assuntos
Abscesso Epidural , Espondilartrite , Espondilite , Humanos , Feminino , Masculino , Abscesso Epidural/diagnóstico por imagem , Abscesso Epidural/cirurgia , Abscesso Epidural/complicações , Estudos Retrospectivos , Espondilite/diagnóstico por imagem , Espondilite/cirurgia , Imageamento por Ressonância Magnética/efeitos adversos , Antibacterianos/uso terapêutico
12.
J Korean Med Sci ; 38(7): e48, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36808543

RESUMO

BACKGROUND: Although, being underweight is commonly associated with osteoporosis and sarcopenia, its association with vertebral fractures (VFs), is less well researched. We investigated the influence of cumulative, chronic periods of low weight and changes in body weight on VF development. METHODS: We used a nationwide, population-based database with data on people (> 40 years) who attended three health screenings between January 1, 2007, and December 31, 2009 to assess the incidence of new VFs. Cox proportional hazard analyses were used to establish the hazard ratios (HRs) for new VFs based on the degree of body mass index (BMI), the cumulative numbers of underweight participants, and temporal change in weight. RESULTS: Of the 561,779 individuals in this analysis, 5,354 (1.0%) people were diagnosed three times, 3,672 (0.7%) were diagnosed twice, and 6,929 (1.2%) were diagnosed once. The fully adjusted HR for VFs in underweight individuals was 1.213. Underweight individuals diagnosed only once, twice, or three times had an adjusted HR of 0.904, 1.443, and 1.256, respectively. Although the adjusted HR was higher in adults who were consistently underweight, there was no difference in those who experienced a temporal change in body weight. BMI, age, sex, and household income were significantly associated with VF incidence. CONCLUSION: Low weight is a risk factor for VFs in the general population. Given the significant correlation between cumulative periods of low weight and the risk of VFs, it is necessary to treat underweight patients before a VF to prevent its development and other osteoporotic fractures.


Assuntos
Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Adulto , Humanos , Estudos de Coortes , Magreza/complicações , Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Densidade Óssea
13.
Am J Hum Genet ; 105(1): 15-28, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31178129

RESUMO

Circulating levels of adiponectin, an adipocyte-secreted protein associated with cardiovascular and metabolic risk, are highly heritable. To gain insights into the biology that regulates adiponectin levels, we performed an exome array meta-analysis of 265,780 genetic variants in 67,739 individuals of European, Hispanic, African American, and East Asian ancestry. We identified 20 loci associated with adiponectin, including 11 that had been reported previously (p < 2 × 10-7). Comparison of exome array variants to regional linkage disequilibrium (LD) patterns and prior genome-wide association study (GWAS) results detected candidate variants (r2 > .60) spanning as much as 900 kb. To identify potential genes and mechanisms through which the previously unreported association signals act to affect adiponectin levels, we assessed cross-trait associations, expression quantitative trait loci in subcutaneous adipose, and biological pathways of nearby genes. Eight of the nine loci were also associated (p < 1 × 10-4) with at least one obesity or lipid trait. Candidate genes include PRKAR2A, PTH1R, and HDAC9, which have been suggested to play roles in adipocyte differentiation or bone marrow adipose tissue. Taken together, these findings provide further insights into the processes that influence circulating adiponectin levels.


Assuntos
Adiponectina/genética , Tecido Adiposo/patologia , Exoma/genética , Predisposição Genética para Doença , Lipídeos/análise , Obesidade/etiologia , Polimorfismo de Nucleotídeo Único , Tecido Adiposo/metabolismo , Adolescente , Adulto , Negro ou Afro-Americano/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Hispânico ou Latino/genética , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Fenótipo , Locos de Características Quantitativas , População Branca/genética , Adulto Jovem
14.
Sex Transm Dis ; 49(3): 184-189, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34561374

RESUMO

BACKGROUND: The persistence of congenital syphilis (CS) remains an important concern in the United States. We use the 2018 data to refine a previous predictive model that identifies US counties at elevated risk for CS in 2018. METHODS: Using county-level socioeconomic and health-related data from various sources, we developed a logistic regression predictive model to identify county-level factors associated with a county having had 1 or more CS case reported to the National Notifiable Diseases Surveillance System in 2018. We developed a risk scoring algorithm, identified the optimal risk score cutpoint to identify counties at elevated risk, and calculated the live birth to CS case ratio for counties by predicted risk level to compare counties at elevated risk with counties not at elevated risk. RESULTS: We identified several county-level factors associated with a county having 1 or more CS case in 2018 (area under the curve, 88.6%; Bayesian information criterion, 1551.1). Using a risk score cutoff of 8 or higher (sensitivity, 83.2%; specificity, 79.4%), this model captured 94.7% (n = 1,253) of CS cases born in 2018 and identified 850 (27%) counties as being at elevated risk for CS. The live birth to CS case ratio was lower in counties identified as at elevated risk (2,482) compared with counties categorized as not at elevated risk (10,621). CONCLUSIONS: Identifying which counties are at highest risk for CS can help target prevention efforts and interventions. The relatively low live birth to CS case ratio in elevated risk counties suggests that implementing routine 28-week screening among pregnant women in these counties may be an efficient way to target CS prevention efforts.


Assuntos
Complicações Infecciosas na Gravidez , Sífilis Congênita , Teorema de Bayes , Pré-Escolar , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Fatores de Risco , Sífilis Congênita/epidemiologia , Sífilis Congênita/prevenção & controle , Estados Unidos/epidemiologia
15.
Sex Transm Dis ; 49(8): 527-533, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34110735

RESUMO

BACKGROUND: Chlamydial infection is associated with tubal factor infertility (TFI); however, assessment of prior chlamydial infection and TFI is imperfect. We previously evaluated a combination of serological assays for association with TFI. We now describe the chlamydial contribution to TFI using a newer Chlamydia trachomatis Pgp3-enhanced serological (Pgp3) assay. METHODS: In our case-control study of women 19 to 42 years old with hysterosalpingogram-diagnosed TFI (cases) and non-TFI (controls) in 2 US infertility clinics, we assessed possible associations and effect modifiers between Pgp3 seropositivity and TFI using adjusted odds ratios with 95% confidence intervals (CIs) stratified by race. We then estimated the adjusted chlamydia population-attributable fraction with 95% CI of TFI. RESULTS: All Black (n = 107) and 618 of 620 non-Black women had Pgp3 results. Pgp3 seropositivity was 25.9% (95% CI, 19.3%-33.8%) for non-Black cases, 15.2% (95% CI, 12.3%-18.7%) for non-Black controls, 66.0% (95% CI, 51.7%-77.8%) for Black cases, and 71.7% (95% CI, 59.2%-81.5%) for Black controls. Among 476 non-Black women without endometriosis (n = 476), Pgp3 was associated with TFI (adjusted odds ratio, 2.6 [95% CI, 1.5-4.4]), adjusting for clinic, age, and income; chlamydia TFI-adjusted population-attributable fraction was 19.8% (95% CI, 7.7%-32.2%) in these women. Pgp3 positivity was not associated with TFI among non-Black women with endometriosis or among Black women (regardless of endometriosis). CONCLUSIONS: Among non-Black infertile women without endometriosis in these clinics, 20% of TFI was attributed to chlamydia. Better biomarkers are needed to estimate chlamydia TFI PAF, especially in Black women.


Assuntos
Infecções por Chlamydia , Endometriose , Infertilidade Feminina , Adulto , Anticorpos Antibacterianos , Estudos de Casos e Controles , Infecções por Chlamydia/complicações , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis , Endometriose/complicações , Endometriose/epidemiologia , Feminino , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/etiologia , Adulto Jovem
16.
Clin Infect Dis ; 73(3): 506-512, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-32507882

RESUMO

BACKGROUND: Neonatal herpes simplex virus infection (nHSV) leads to severe morbidity and mortality, but national incidence is uncertain. Florida regulations require that healthcare providers report cases, and clinical laboratories report test results when herpes simplex virus (HSV) is detected. We estimated nHSV incidence using laboratory-confirmed provider-reported cases and electronic laboratory reports (ELR) stored separately from provider-reported cases. Mortality was estimated using provider-reported cases, ELR, and vital statistics death records. METHODS: For 2011-2017, we reviewed: provider-reported cases (infants ≤ 60 days of age with HSV infection confirmed by culture or polymerase chain reaction [PCR]), ELR of HSV-positive culture or PCR results in the same age group, and death certificates containing International Classification of Disease, Tenth Revision, codes for herpes infection: P35.2, B00.0-B00.9, and A60.0-A60.9. Provider-reported cases were matched against ELR reports. Death certificates were matched with provider and ELR reports. Chapman's capture-recapture method was used to estimate nHSV incidence and mortality. Mortality from all 3 sources was estimated using log-linear modeling. RESULTS: Providers reported 114 nHSV cases, and ELR identified 197 nHSV cases. Forty-six cases were common to both datasets, leaving 265 unique nHSV reports. Chapman's estimate suggests 483 (95% confidence interval [CI], 383-634) nHSV cases occurred (31.5 infections per 100 000 live births). The nHSV deaths were reported by providers (n = 9), ELR (n = 18), and vital statistics (n = 31), totaling 34 unique reports. Log-linear modeling estimates 35.8 fatal cases occurred (95% CI, 34-40). CONCLUSIONS: Chapman's estimates using data collected over 7 years in Florida conclude nHSV infections occurred at a rate of 1 per 3000 live births.


Assuntos
Herpes Simples , Florida/epidemiologia , Herpes Simples/diagnóstico , Herpes Simples/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Complicações Infecciosas na Gravidez , Simplexvirus
17.
Clin Infect Dis ; 73(8): 1507-1516, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34050737

RESUMO

BACKGROUND: Chlamydia trachomatis causes pelvic inflammatory disease (PID) and tubal infertility. Plasmid gene protein 3 antibody (Pgp3Ab) detects prior chlamydial infections. We evaluated for an association of high chlamydial seropositivity with sequelae using a Pgp3Ab multiplex bead array (Pgp3AbMBA). METHODS: We performed chlamydia Pgp3AbMBA on sera from women 18-39 years old participating in the 2013-2016 National Health and Nutrition Examination Survey (NHANES) with urine chlamydia nucleic acid amplification test results. High chlamydial seropositivity was defined as a median fluorescence intensity (MFI ≥ 50 000; low-positive was MFI > 551-<50 000. Weighted US population high-positive, low-positive, and negative Pgp3Ab chlamydia seroprevalence and 95% confidence intervals (CI) were compared for women with chlamydial infection, self-reported PID, and infertility. RESULTS: Of 2339 women aged 18-39 years, 1725 (73.7%) had sera, and 1425 were sexually experienced. Overall, 104 women had high positive Pgp3Ab (5.4% [95% CI 4.0-7.0] of US women); 407 had lowpositive Pgp3Ab (25.1% [95% CI 21.5-29.0]), and 914 had negative Pgp3Ab (69.5% [95% CI 65.5-73.4]). Among women with high Pgp3Ab, infertility prevalence was 2.0 (95% CI 1.1-3.7) times higher than among Pgp3Ab-negative women (19.6% [95% CI 10.5-31.7] versus 9.9% [95% CI 7.7-12.4]). For women with low Pgp3Ab, PID prevalence was 7.9% (95% CI 4.6-12.6) compared to 2.3% (95% CI 1.4-3.6) in negative Pgp3Ab. CONCLUSIONS: High chlamydial Pgp3Ab seropositivity was associated with infertility although small sample size limited evaluation of an association of high seropositivity with PID. In infertile women, Pgp3Ab may be a marker of prior chlamydial infection.


Assuntos
Infecções por Chlamydia , Infertilidade Feminina , Doença Inflamatória Pélvica , Adolescente , Adulto , Infecções por Chlamydia/complicações , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis , Feminino , Humanos , Infertilidade Feminina/epidemiologia , Inquéritos Nutricionais , Doença Inflamatória Pélvica/epidemiologia , Plasmídeos , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia , Adulto Jovem
18.
Sex Transm Dis ; 48(12S Suppl 2): S111-S117, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34475363

RESUMO

BACKGROUND: We investigated differences in gonococcal antimicrobial susceptibility by anatomic site among cisgender men who have sex with men (MSM) using specimens collected through the Centers for Disease Control and Prevention's enhanced Gonococcal Isolate Surveillance Project and Strengthening the US Response to Resistant Gonorrhea. METHODS: During the period January 1, 2018-December 31, 2019, 12 enhanced Gonococcal Isolate Surveillance Project and 8 Strengthening the US Response to Resistant Gonorrhea sites collected urogenital, pharyngeal, and rectal isolates from cisgender MSM in sexually transmitted disease clinics. Gonococcal isolates were sent to regional laboratories for antimicrobial susceptibility testing by agar dilution. To account for correlated observations, linear mixed-effects models were used to calculate geometric mean minimum inhibitory concentrations (MICs), and mixed-effects logistic regression models were used to calculate the proportion of isolates with elevated or resistant MICs; comparisons were made across anatomic sites. RESULTS: Participating clinics collected 3974 urethral, 1553 rectal, and 1049 pharyngeal isolates from 5456 unique cisgender MSM. There were no significant differences in the geometric mean MICs for azithromycin, ciprofloxacin, penicillin, and tetracycline by anatomic site. For cefixime and ceftriaxone, geometric mean MICs for pharyngeal isolates were higher compared with anogenital isolates (P < 0.05). The proportion of isolates with elevated ceftriaxone MICs (≥0.125 µg/mL) at the pharynx (0.67%) was higher than at rectal (0.13%) and urethral (0.18%) sites (P < 0.05). CONCLUSIONS: Based on data collected from multijurisdictional sentinel surveillance projects, antimicrobial susceptibility patterns of Neisseria gonorrhoeae isolates may differ among MSM at extragenital sites, particularly at the pharynx. Continued investigation into gonococcal susceptibility patterns by anatomic site may be an important strategy to monitor and detect the emergence of antimicrobial resistant gonorrhea over time.


Assuntos
Gonorreia , Minorias Sexuais e de Gênero , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ciprofloxacina , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae
19.
J Am Chem Soc ; 142(30): 13201-13209, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32628842

RESUMO

By combining single-molecule fluorescence microscopy with traditional electrochemical methods, herein we report on the investigation of the electrocatalytic kinetics of two-electron (2e) pathway of oxygen reduction reaction (ORR) on a single Fe3O4 nanoparticle. The kinetic parameters for two-electron ORR process are successfully derived at the single-particle level, and a potential dependence of dynamic heterogeneity among individual nanoparticles is revealed. Furthermore, the performance stability of individual Fe3O4 nanoparticles for 2e ORR process is studied. This study deepens our understanding to the electrocatalytic ORR process, especially the 2e pathway at single-molecule and single-particle levels.

20.
Stat Med ; 39(3): 207-219, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-31846099

RESUMO

Latent class analysis (LCA) has been effectively used to cluster multiple survey items. However, causal inference with an exposure variable, identified by an LCA model, is challenging because (1) the exposure variable is unobserved and harbors the uncertainty of estimating parameters in the LCA model and (2) confounding bias adjustments need to be done with the unobserved LCA-driven exposure variable. In addition to these challenges, complex survey design features and survey weights must be accounted for if they are present. Our solutions to these issues are to (1) assess point estimates with the expected estimating function approach and (2) modify the survey design weights with LCA-based propensity scores. This paper aims to introduce a statistical procedure to apply the estimating equation approach to assessing the effects of LCA-driven cause in complex survey data using an example of the National Health and Nutrition Examination Survey.


Assuntos
Causalidade , Análise de Classes Latentes , Inquéritos e Questionários , Simulação por Computador , Humanos
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