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1.
Am J Public Health ; 109(S4): S303-S308, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505137

RESUMO

Objectives. To assess preparedness levels of communities to help public health and others plan for disasters or emergencies and tailor messaging to increase community preparedness.Methods. US Virgin Islands Department of Health conducted a Community Assessment for Public Health Emergency Response (CASPER) in June 2017, 2 hurricane response CASPERs in November 2017, and a recovery CASPER in February 2018. CASPER is a 2-stage cluster sampling method designed to provide household-based information about a community's needs in a timely, inexpensive, and representative manner.Results. Roughly the same amount of households reported having a 3-day supply of food and water before and 3 months after the hurricanes. During the response, approximately a third of households resupplied between 3 and 6 days and an additional approximately 40% between days 7 and 14.Conclusions. On the basis of the CASPERs, we were able to track whether households had an emergency preparedness kit, whether they used it during the storms (and what was missing), and if they resupplied their kit in recovery.Public Health Implications. CASPER is a promising tool to measure community preparedness to help state, local, tribal, and territorial jurisdictions plan for disasters or emergencies.


Assuntos
Planejamento em Desastres/métodos , Avaliação das Necessidades , Tempestades Ciclônicas , Água Potável , Emergências , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Saúde Pública , Ilhas Virgens Americanas
2.
MMWR Morb Mortal Wkly Rep ; 68(22): 500-504, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31170124

RESUMO

Aedes aegypti, the mosquito that carries dengue, chikungunya, and Zika viruses, is present throughout the U.S. Virgin Islands (USVI). To reduce mosquitoborne disease transmission, the USVI Department of Health (VIDOH) is responsible for integrated mosquito management. During January 2016-January 2018, USVI experienced its first Zika outbreak, with most cases reported during January-December 2016, as well as two Category 5 hurricanes (Irma on St. Thomas/St. John on September 6, 2017, and Maria on St. Croix on September 19, 2017). The hurricanes severely damaged mosquito protection-related building structures (e.g., screens, roofs) and infrastructure (e.g., electricity, air conditioning) and might have created an environment more conducive to mosquito breeding. VIDOH, with requested technical assistance from CDC, conducted three Community Assessments for Public Health Emergency Response (CASPERs) to provide rapid community information at the household level. The three CASPERs were conducted to inform 1) the Zika outbreak response, 2) the hurricane response, and 3) the hurricane recovery. The CASPERs assessed mosquito prevention and control-related experiences, attitudes, and practices; household and environmental conditions associated with mosquito breeding, prevention, and control; and other nonmosquito-related information to inform outbreak and disaster response planning. Approximately 40% of households were very concerned about contracting Zika virus during the Zika outbreak and hurricane responses. Environmental conditions were reported to become more favorable for mosquito breeding between the Zika outbreak and hurricane response. Between 75%-80% of the community supported mosquito-spraying in all assessments. VIDOH used these data to support real-time outbreak and hurricane response planning. Mosquito prevention and control community assessments can provide rapid, actionable information to advise both mosquito education and control and emergency response and recovery efforts. The CASPER design can be used by vector control programs to enhance routine and response operations.


Assuntos
Tempestades Ciclônicas , Surtos de Doenças/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Controle de Mosquitos/métodos , Características de Residência , Infecção por Zika virus/prevenção & controle , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Ilhas Virgens Americanas/epidemiologia , Adulto Jovem , Infecção por Zika virus/epidemiologia
5.
Langmuir ; 33(32): 7889-7895, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28742968

RESUMO

Thin bilayers of contrasting nanomaterials are ubiquitous in solution-processed electronic devices and have potential relevance to a number of applications in flexible electronics. Motivated by recent mesoscopic simulations demonstrating synergistic mechanical interactions between thin films of single-wall carbon nanotubes (SWCNTs) and spherical nanocrystal (NC) inclusions, we use a thin-film wrinkling approach to query the compressive mechanics of hybrid nanotube/nanocrystal coatings adhered to soft polymer substrates. Our results show an almost 2-fold enhancement in the Young modulus of a sufficiently thin SWCNT film associated with the presence of a thin interpenetrating overlayer of semiconductor NCs. Mesoscopic distinct-element method simulations further support the experimental findings by showing that the additional noncovalent interfaces introduced by nanocrystals enhance the modulus of the SWCNT network and hinder network wrinkling.

6.
MMWR Morb Mortal Wkly Rep ; 66(34): 909-913, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28859049

RESUMO

As of May 2, 2017, the U.S. Virgin Islands (USVI), comprising St. Thomas, St. John, and St. Croix, had reported 1,021 probable or confirmed cases* of Zika virus disease in its population of approximately 100,000 (1); 222 symptomatic and asymptomatic pregnant women in the USVI had tested positive for Zika virus. In January 2016, USVI Department of Health (USVI DOH) initiated Zika response measures, including surveillance, vector control, and a communications program. Interventions included education and outreach, distribution of Zika prevention kits† to pregnant women in the USVI, and provision of free Zika virus laboratory testing and vector control services. In November 2016, USVI DOH staff members conducted interviews with convenience samples of community members and pregnant women to gather feedback about current and proposed interventions (2). Pregnant women reported taking a median of two actions to protect themselves from Zika, with repellent use being the most commonly reported action. Community members reported taking a median of one action and were supportive of several proposed vector control approaches. Whereas multiple pregnant women and community members reported hearing messages about the cause and consequences of Zika virus infections, few recalled messages about specific actions they could take to protect themselves. Integrating evaluation into response measures permits ongoing assessment of intervention effectiveness and supports improvement to serve the population's needs.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Complicações Infecciosas na Gravidez/prevenção & controle , Gestantes/psicologia , Infecção por Zika virus/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Repelentes de Insetos , Masculino , Pessoa de Meia-Idade , Controle de Mosquitos , Gravidez , Ilhas Virgens Americanas , Adulto Jovem
7.
Soft Matter ; 12(18): 4229-40, 2016 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-27049110

RESUMO

Charged spherical nanoparticles trapped at the interface between water and air or water and oil exhibit repulsive electrostatic forces that contain a long-ranged dipolar and a short-ranged exponentially decaying component. The former are induced by the unscreened electrostatic field through the non-polar low-permittivity medium, and the latter result from the overlap of the diffuse ion clouds that form in the aqueous phase close to the nanoparticles. The magnitude of the long-ranged dipolar interaction is largely determined by the residual charges that remain attached to the air- (or oil-) exposed region of the nanoparticle. In the present work we address the question to what extent the charges on the water-immersed part of the nanoparticle provide an additional contribution to the dipolar interaction. To this end, we model the electrostatic properties of a spherical particle - a nanoparticle or a colloid - that partitions equatorially to the air-water interface, thereby employing nonlinear Poisson-Boltzmann theory in the aqueous solution and accounting for the propagation of the electric field through the interior of the particle. We demonstrate that the apparent charge density on the air-exposed region of the particle, which determines the dipole potential, is influenced by the electrostatic properties in the aqueous solution. We also show that this electrostatic coupling through the particle can be reproduced qualitatively by a simple analytic planar capacitor model. Our results help to rationalize the experimentally observed weak but non-vanishing salt dependence of the forces that stabilize ordered two-dimensional arrays of interface-trapped nanoparticles or colloids.

8.
Langmuir ; 31(36): 9924-32, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26302019

RESUMO

Mixed fluid-like lipid membranes exhibit interactions not only among the lipids within a given leaflet but also across the bilayer. The ensuing collective interleaflet coupling of entire membrane domains has been modeled previously using various mean-field approaches. Yet, also on the level of individual lipids have correlations across the bilayer been observed experimentally for binary mixtures of charged/uncharged lipids with mismatching combinations of short and long acyl chain lengths. The present study proposes a lattice gas model to quantify these correlations. To this end, we represent a macroscopically homogeneous lipid bilayer by two coupled two-dimensional lattice gases that we study using the quasi-chemical approximation. We demonstrate that the rationalization of previous experimental results is only possible if besides two-body lipid-lipid interactions within and across the bilayer our model also accounts for an additional multibody interaction mechanism, namely the local hydrophobic height mismatch created by pairing short and long chain lipids together. The robustness of the quasi-chemical approximation is verified by comparison with Monte Carlo simulations.


Assuntos
Bicamadas Lipídicas/química , Lipídeos/química , Modelos Químicos , Método de Monte Carlo
9.
Ann Epidemiol ; 95: 1-5, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38740077

RESUMO

PURPOSE: The U.S. Virgin Islands (USVI) receives an updated population count once every 10 years and used 2010 decennial census population counts to estimate COVID-19 vaccination coverage during the COVID-19 emergency response. We investigated whether using outdated (2010) or modeled (2020 international database [IDB]) population counts biased vaccination coverage estimates used to inform public health priorities during the 2020-2022 COVID-19 response. METHODS: We estimated percentage of USVI residents with a completed primary COVID-19 vaccination series during December 16, 2020-September 20, 2022. Vaccination coverage was calculated as number of persons who completed the vaccination series divided by 2010 and 2020 decennial census population counts and 2020 IDB intercensal estimate. RESULTS: COVID-19 vaccination coverage using the 2020 population count was 12 % points higher than coverage using 2010 denominator (2010 denominator: 51 %; 2020 denominator: 63 %). Vaccination coverage estimated using 2020 IDB was approximately equal with the 2010 decennial census estimate (52 %). CONCLUSIONS: Using 2010 and modeled population counts underestimated 2020 USVI COVID-19 vaccination coverage given the 18 % population decline during 2010-2020, potentially limiting USVI's ability to assess vaccination progress. Identifying mechanisms for more reliable population enumeration or improved estimate modeling are essential for accurately guiding USVI public health decision-making.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Cobertura Vacinal , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Cobertura Vacinal/estatística & dados numéricos , Vacinas contra COVID-19/administração & dosagem , Ilhas Virgens Americanas/epidemiologia , Feminino , Adulto , Masculino , Pessoa de Meia-Idade , Idoso , Adolescente , Vacinação/estatística & dados numéricos , Viés , Adulto Jovem
10.
Nat Commun ; 15(1): 5304, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914537

RESUMO

Advancements in materials synthesis have been key to unveil the quantum nature of electronic properties in solids by providing experimental reference points for a correct theoretical description. Here, we report hidden transport phenomena emerging in the ultraclean limit of the archetypical correlated electron system SrVO3. The low temperature, low magnetic field transport was found to be dominated by anisotropic scattering, whereas, at high temperature, we find a yet undiscovered phase that exhibits clear deviations from the expected Landau Fermi liquid, which is reminiscent of strange-metal physics in materials on the verge of a Mott transition. Further, the high sample purity enabled accessing the high magnetic field transport regime at low temperature, which revealed an anomalously high Hall coefficient. Taken with the strong anisotropic scattering, this presents a more complex picture of SrVO3 that deviates from a simple Landau Fermi liquid. These hidden transport anomalies observed in the ultraclean limit prompt a theoretical reexamination of this canonical correlated electron system beyond the Landau Fermi liquid paradigm, and more generally serves as an experimental basis to refine theoretical methods to capture such nontrivial experimental consequences emerging in correlated electron systems.

11.
Vector Borne Zoonotic Dis ; 22(12): 600-605, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36399688

RESUMO

Background: The first Zika virus outbreak in U.S. Virgin Islands identified 1031 confirmed noncongenital Zika disease (n = 967) and infection (n = 64) cases during January 2016-January 2018; most cases (89%) occurred during July-December 2016. Methods and Results: The epidemic followed a continued point-source outbreak pattern. Evaluation of sociodemographic risk factors revealed that estates with higher unemployment, more houses connected to the public water system, and more newly built houses were significantly less likely to have Zika virus disease and infection cases. Increased temperature was associated with higher case counts, which suggests a seasonal association of this outbreak. Conclusion: Vector surveillance and control measures are needed to prevent future outbreaks.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/veterinária
12.
PLoS Negl Trop Dis ; 16(11): e0010880, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36378681

RESUMO

BACKGROUND: The first documented human leptospirosis cases in the U.S. Virgin Islands (USVI) occurred following 2017 Hurricanes Irma and Maria. We conducted a representative serosurvey in USVI to estimate the seroprevalence and distribution of human leptospirosis and evaluate local risk factors associated with seropositivity. METHODOLOGY/PRINCIPAL FINDINGS: A stratified, two-stage cluster sampling design was used and consisted of three island strata and random selection of census blocks and then households. All eligible members of selected households were invited to participate (≥5 years old, resided in USVI ≥6 months and ≥6 months/year). Household and individual-level questionnaires were completed, and serum collected from each enrolled individual. Microscopic agglutination test serology was conducted, and bivariate and logistic regression analyses completed to identify risk factors for seropositivity. In March 2019, 1,161 individuals were enrolled from 918 households in St. Croix, St. Thomas, and St. John. The territory-wide weighted seroprevalence was 4.0% (95% CI:2.3-5.7). Characteristics/exposures independently associated with seropositivity using logistic regression included contact with cows (OR: 39.5; 95% CI: 9.0-172.7), seeing rodents/rodent evidence or contact with rodents (OR: 2.6; 95% CI: 1.1-5.9), and increasing age (OR: 1.02; 95% CI: 1.002-1.04); full or partial Caucasian/White race was negatively correlated with seropositivity (OR: 0.02, 95% CI: 0.04-0.7). Bivariate analysis showed self-reported jaundice since the 2017 hurricanes (pRR: 5.7; 95% CI: 1.0-33.4) was associated with seropositivity and using a cover/lid on cisterns/rainwater collection containers (pRR: 0.3; 95% CI: 0.08-0.8) was protective against seropositivity. CONCLUSIONS/SIGNIFICANCE: Leptospirosis seropositivity of 4% across USVI demonstrates an important human disease that was previously unrecognized and emphasizes the importance of continued leptospirosis surveillance and investigation. Local risk factors identified may help guide future human and animal leptospirosis studies in USVI, strengthen leptospirosis public health surveillance and treatment timeliness, and inform targeted education, prevention, and control efforts.


Assuntos
Leptospirose , Feminino , Humanos , Bovinos , Animais , Pré-Escolar , Estudos Soroepidemiológicos , Ilhas Virgens Americanas/epidemiologia , Leptospirose/epidemiologia , Testes de Aglutinação , Fatores de Risco
13.
Sci Rep ; 12(1): 1132, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064157

RESUMO

Leptospirosis is a global zoonotic disease caused by pathogenic bacteria of the genus Leptospira. We sought to determine if rodents in U.S. Virgin Islands (USVI) are carriers of Leptospira. In total, 140 rodents were sampled, including 112 Mus musculus and 28 Rattus rattus. A positive carrier status was identified for 64/140 (45.7%); 49 (35.0%) were positive by dark-field microscopy, 60 (42.9%) by culture, 63 (45.0%) by fluorescent antibody testing, and 61 (43.6%) by real-time polymerase chain reaction (rtPCR). Molecular typing indicated that 48 isolates were L. borgpetersenii and 3 were L. kirschneri; the remaining nine comprised mixed species. In the single culture-negative sample that was rtPCR positive, genotyping directly from the kidney identified L. interrogans. Serotyping of L. borgpetersenii isolates identified serogroup Ballum and L. kirschneri isolates as serogroup Icterohaemorrhagiae. These results demonstrate that rodents are significant Leptospira carriers and adds to understanding the ecoepidemiology of leptospirosis in USVI.


Assuntos
Portador Sadio/epidemiologia , Reservatórios de Doenças/microbiologia , Leptospira/isolamento & purificação , Leptospirose/veterinária , Doenças dos Roedores/epidemiologia , Animais , Portador Sadio/diagnóstico , Portador Sadio/microbiologia , Portador Sadio/transmissão , Feminino , Humanos , Leptospira/genética , Leptospirose/epidemiologia , Leptospirose/microbiologia , Leptospirose/transmissão , Masculino , Camundongos , Tipagem Molecular , Saúde Pública , Ratos , Doenças dos Roedores/diagnóstico , Doenças dos Roedores/microbiologia , Doenças dos Roedores/transmissão , Ilhas Virgens Americanas/epidemiologia , Zoonoses
14.
J Emerg Manag ; 19(8): 63-77, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36239499

RESUMO

On September 6 and 20, 2017, Hurricanes Irma and Maria made landfall as major hurricanes in the US Caribbean Territories of the Virgin Islands and Puerto Rico with devastating effects. As part of the initial response, a public health team (PHT) was initially deployed as part of the US Department of Health and Human Services Incident Response Coordination Team. As a result of increased demands for additional expertise and resources, a public health branch (PHB) was established for coordinating a broad spectrum of public health response activities in support of the affected territories. This paper describes the conceptual framework for organizing these activities; summarizes some key public health activities and roles; outlines partner support and coordination with key agencies; and defines best practices and areas for improvement in disaster future operations.


Assuntos
Tempestades Ciclônicas , Governo Federal , Humanos , Saúde Pública , Porto Rico , Ilhas Virgens Americanas
15.
PLoS Negl Trop Dis ; 15(7): e0009536, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34264951

RESUMO

Mongooses, a nonnative species, are a known reservoir of rabies virus in the Caribbean region. A cross-sectional study of mongooses at 41 field sites on the US Virgin Islands of St. Croix, St. John, and St. Thomas captured 312 mongooses (32% capture rate). We determined the absence of rabies virus by antigen testing and rabies virus exposure by antibody testing in mongoose populations on all three islands. USVI is the first Caribbean state to determine freedom-from-rabies for its mongoose populations with a scientifically-led robust cross-sectional study. Ongoing surveillance activities will determine if other domestic and wildlife populations in USVI are rabies-free.


Assuntos
Animais Selvagens/virologia , Reservatórios de Doenças/virologia , Herpestidae/virologia , Vírus da Raiva/isolamento & purificação , Animais , Estudos Transversais , Vírus da Raiva/classificação , Vírus da Raiva/genética , Ilhas Virgens Americanas
16.
PLoS Negl Trop Dis ; 15(11): e0009859, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34780473

RESUMO

During 2019-2020, the Virgin Islands Department of Health investigated potential animal reservoirs of Leptospira spp., the bacteria that cause leptospirosis. In this cross-sectional study, we investigated Leptospira spp. exposure and carriage in the small Indian mongoose (Urva auropunctata, syn: Herpestes auropunctatus), an invasive animal species. This study was conducted across the three main islands of the U.S. Virgin Islands (USVI), which are St. Croix, St. Thomas, and St. John. We used the microscopic agglutination test (MAT), fluorescent antibody test (FAT), real-time polymerase chain reaction (lipl32 rt-PCR), and bacterial culture to evaluate serum and kidney specimens and compared the sensitivity, specificity, positive predictive value, and negative predictive value of these laboratory methods. Mongooses (n = 274) were live-trapped at 31 field sites in ten regions across USVI and humanely euthanized for Leptospira spp. testing. Bacterial isolates were sequenced and evaluated for species and phylogenetic analysis using the ppk gene. Anti-Leptospira spp. antibodies were detected in 34% (87/256) of mongooses. Reactions were observed with the following serogroups: Sejroe, Icterohaemorrhagiae, Pyrogenes, Mini, Cynopteri, Australis, Hebdomadis, Autumnalis, Mankarso, Pomona, and Ballum. Of the kidney specimens examined, 5.8% (16/270) were FAT-positive, 10% (27/274) were culture-positive, and 12.4% (34/274) were positive by rt-PCR. Of the Leptospira spp. isolated from mongooses, 25 were L. borgpetersenii, one was L. interrogans, and one was L. kirschneri. Positive predictive values of FAT and rt-PCR testing for predicting successful isolation of Leptospira by culture were 88% and 65%, respectively. The isolation and identification of Leptospira spp. in mongooses highlights the potential role of mongooses as a wildlife reservoir of leptospirosis; mongooses could be a source of Leptospira spp. infections for other wildlife, domestic animals, and humans.


Assuntos
Reservatórios de Doenças/microbiologia , Herpestidae/microbiologia , Leptospira/isolamento & purificação , Testes de Aglutinação , Animais , Estudos Transversais , Herpestidae/fisiologia , Humanos , Espécies Introduzidas/estatística & dados numéricos , Rim/microbiologia , Leptospira/genética , Leptospira/imunologia , Leptospirose/microbiologia , Leptospirose/transmissão , Filogenia , Ilhas Virgens Americanas
17.
ACS Appl Mater Interfaces ; 12(27): 30520-30529, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32515187

RESUMO

Expanding the application space of transparent electrodes toward the ultraviolet range has been found challenging when utilizing the conventional approach to degenerately dope semiconductors with band gaps larger than ZnO or In2O3. Here, it is shown that the correlated metal SrxNbO3 with x < 1 is ideally suited as a UV-transparent electrode material, enabling UV light-emitting diodes for a wide range of applications from water disinfection to polymer curing. It is demonstrated that SrxNbO3 thin films can be grown by radio frequency (RF) sputtering and that they remain in the perovskite phase despite a sizeable Sr deficiency. The electrical and optical properties are characterized and compared to those of commonly used indium tin oxide (ITO) and Sn-doped Ga2O3 transparent conductor standards. SrxNbO3 films were found to have sheet resistances as low as 30 Ω sq-1 with optical transmission at a wavelength of 280 nm up to 86%, marking a two-order-of-magnitude increase over the performance of traditional UV-transparent conductors. The compatibility of SrxNbO3 with a physical vapor deposition technique that is widely employed in the transparent conductor coating industry along with the robustness of the highly electrically conducting and optically transparent perovskite phase makes it an ideal transparent electrode for applications in the UV spectrum.

18.
Disaster Med Public Health Prep ; 17: e5, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32452338

RESUMO

The Centers for Disease Control and Prevention (CDC), Division of State and Local Readiness (DSLR), Public Health Emergency Preparedness(PHEP) program funds 62 recipients to strengthen capability standards to prepare for and respond to public health emergencies. Recipients use these PHEP resources in addition to CDC's administrative and scientific guidance to support preparedness and response program planning and requirements. It is expected that public health agencies develop and maintain comprehensive emergency preparedness and response plans in preparation for disasters such as hurricanes. The 2017 historic hurricane season highlighted how emergency planning and collaborative operational execution is important for public health agencies to effectively prepare for and respond to both the immediate and long-term population health consequences of these disasters. In 2017, the southeastern United States (US) and US Caribbean territories experienced 3 Category 4 or higher Atlantic hurricanes (Harvey, Irma, and Maria) within a 5-week period. This paper highlights selected case studies that illustrate the contributions and impact of jurisdictional emergency management planning and operational capacity supported by capability standards during the 2017 hurricane season. Although the magnitude of the 2017 hurricanes required public health officials to seek additional assistance, the following case studies describe the use of public health preparedness systems and recovery resources supported by the PHEP program.

19.
J Tissue Eng Regen Med ; 14(8): 1037-1049, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32483878

RESUMO

Massive craniofacial bone loss poses a clinical challenge to maxillofacial surgeons. Structural bone allografts are readily available at tissue banks but are rarely used due to a high failure rate. Previous studies showed that intermittent administration of recombinant parathyroid hormone (rPTH) enhanced integration of allografts in a murine model of calvarial bone defect. To evaluate its translational potential, the hypothesis that rPTH would enhance healing of a mandibular allograft in a clinically relevant large animal model of mandibulectomy was tested. Porcine bone allografts were implanted into a 5-cm-long continuous mandible bone defect in six adult Yucatan minipigs, which were randomized to daily intramuscular injections of rPTH (1.75 µg/kg) and placebo (n = 3). Blood tests were performed on Day 56 preoperation, Day 0 and on Day 56 postoperation. Eight weeks after the surgery, bone healing was analyzed using high-resolution X-ray imaging (Faxitron and micro computed tomography [CT]) and three-point bending biomechanical testing. The results showed a significant 2.6-fold rPTH-induced increase in bone formation (p = 0.02). Biomechanically, the yield failure properties of the healed mandibles were significantly higher in the rPTH group (yield load: p < 0.05; energy to yield: p < 0.01), and the post-yield displacement and energy were higher in the placebo group (p < 0.05), suggesting increased mineralized integration of the allograft in the rPTH group. In contrast to similar rPTH therapy studies in dogs, no signs of hypercalcemia, hyperphosphatemia, or inflammation were detected. Taken together, we provide initial evidence that rPTH treatment enhances mandibular allograft healing in a clinically relevant large animal model.


Assuntos
Transplante Ósseo , Mandíbula/transplante , Traumatismos Mandibulares/terapia , Osteotomia Mandibular , Osteogênese/efeitos dos fármacos , Teriparatida/farmacologia , Aloenxertos , Animais , Feminino , Suínos , Porco Miniatura
20.
Nat Commun ; 10(1): 2464, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165726

RESUMO

The availability of native substrates is a cornerstone in the development of microelectronic technologies relying on epitaxial films. If native substrates are not available, virtual substrates - crystalline buffer layers epitaxially grown on a structurally dissimilar substrate - offer a solution. Realizing commercially viable virtual substrates requires the growth of high-quality films at high growth rates for large-scale production. We report the stoichiometric growth of SrTiO3 exceeding 600 nm hr-1. This tenfold increase in growth rate compared to SrTiO3 grown on silicon by conventional methods is enabled by a self-regulated growth window accessible in hybrid molecular beam epitaxy. Overcoming the materials integration challenge for complex oxides on silicon using virtual substrates opens a path to develop new electronic devices in the More than Moore era and silicon integrated quantum computation hardware.

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