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1.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505957

RESUMO

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

2.
Phys Rev Lett ; 131(26): 262501, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38215380

RESUMO

The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.

3.
Chembiochem ; 23(3): e202100614, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34881485

RESUMO

Cycles of dehydration and rehydration could have enabled formation of peptides and RNA in otherwise unfavorable conditions on the early Earth. Development of the first protocells would have hinged upon colocalization of these biopolymers with fatty acid membranes. Using atomic force microscopy, we find that a prebiotic fatty acid (decanoic acid) forms stacks of membranes after dehydration. Using LC-MS-MS (liquid chromatography-tandem mass spectrometry) with isotope internal standards, we measure the rate of formation of serine dipeptides. We find that dipeptides form during dehydration at moderate temperatures (55 °C) at least as fast in the presence of decanoic acid membranes as in the absence of membranes. Our results are consistent with the hypothesis that protocells could have formed within evaporating environments on the early Earth.


Assuntos
Ácidos Decanoicos/química , Peptídeos/síntese química , Desidratação , Peptídeos/química , Conformação Proteica , Temperatura
4.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332266

RESUMO

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

5.
Public Health ; 198: 146-155, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34428607

RESUMO

OBJECTIVES: This study aimed to investigate the extent and key characteristics of academic research and scholarship on the public health community's use of social media for policy advocacy purposes. This will enable an evaluation of extant research and provide insight into directions for future research. STUDY DESIGN: This study was a scoping review of academic literature. METHODS: A scoping review of academic literature published between 1 January 2011 and 31 December 2020 was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework. Boolean searches were conducted using a university library platform, which included databases, such as EBSCO host, Informit, Scopus, and ScienceDirect. Data were extracted using an a priori code frame, and publication, content, and disciplinary characteristics were analysed. The results of coding and screening comparison checks were within acceptable limits. RESULTS: In total, 2672 works from around the world were identified and screened for inclusion. Twenty-two English language articles were included in the final analysis. The public health community's use of social media for policy advocacy purposes has largely been approached from a health perspective, despite research and scholarship about social media in communication and policy disciplines (among others). Reported research aims or questions emphasised functional rather than theoretical contributions. Most analysed works used empirical or case study-based methods and were produced by authors in Western geographies. Among the health issues discussed, tobacco and tobacco control were discussed most frequently. While recognising issues with social media, most publications framed social media as more of an opportunity than a problem. CONCLUSIONS: The public health community's use of social media for policy advocacy purposes is an emerging field. There is considerable potential to expand scholarship and research in this field internationally, especially by integrating transdisciplinary knowledge and perspectives and by applying social media to foster policy change around identified global health challenges. Greater representation of authors from institutions in the Global South is also encouraged, as are applied and theoretical contributions.


Assuntos
Mídias Sociais , Atenção à Saúde , Saúde Global , Humanos , Políticas , Saúde Pública
6.
Phys Rev Lett ; 125(19): 192501, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216605

RESUMO

The ß decay of ^{208}Hg into the one-proton hole, one neutron-particle _{81}^{208}Tl_{127} nucleus was investigated at CERN-ISOLDE. Shell-model calculations describe well the level scheme deduced, validating the proton-neutron interactions used, with implications for the whole of the N>126, Z<82 quadrant of neutron-rich nuclei. While both negative and positive parity states with spin 0 and 1 are expected within the Q_{ß} window, only three negative parity states are populated directly in the ß decay. The data provide a unique test of the competition between allowed Gamow-Teller and Fermi, and first-forbidden ß decays, essential for the understanding of the nucleosynthesis of heavy nuclei in the rapid neutron capture process. Furthermore, the observation of the parity changing 0^{+}→0^{-}ß decay where the daughter state is core excited is unique, and can provide information on mesonic corrections of effective operators.

7.
Transfusion ; 59(4): 1246-1251, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30592057

RESUMO

BACKGROUND: Platelet inventory constraints can result in minor ABO incompatibility and possible hemolysis. The aims of this study were to determine the reduction of isoagglutinin in titers of platelets stored in additive solution (PAS) and compare its safety, efficiency, and cost-effectiveness with full-volume and plasma-reduced platelets. STUDY DESIGN AND METHODS: Isoagglutinin titers were performed in paired whole blood donor samples and apheresis platelets collected in PAS (PAS-PLT) aliquot samples by the tube method. RESULTS: A total of 149 pairs of donor/platelet samples were tested: 75 group O, 59 group A, and 15 group B. For group O donor samples, the median anti-A IgG and IgM were 64 and 16, respectively, and the median anti-B IgG and IgM were 64 and 16, respectively. For group O PAS-PLT samples the mean anti-A IgG and IgM, and anti-B IgG and IgM were 32 and 8, and 16 and 8, respectively. For group A donor samples, the mean anti-B IgG and IgM was 8 in both cases; and both titers decreased to 2 in PAS-PLT. For group B donor samples, mean anti-A IgG and IgM was 16 in both cases; and both titers decreased to 4 in PAS-PLT. PAS-PLT demonstrated a net reduction in cost and improved efficiency when compared to plasma reduction. The use of PAS-PLT resulted in a 40% reduction of allergic transfusion reactions. CONCLUSION: The use of PAS decreases plasma isoagglutinin titers, transfusion reactions, and is cost-effective when compared to routine plasma reduction as a strategy to mitigate hemolysis risk from minor incompatible platelet transfusion.


Assuntos
Incompatibilidade de Grupos Sanguíneos/prevenção & controle , Preservação de Sangue/métodos , Hemólise , Transfusão de Plaquetas/efeitos adversos , Reação Transfusional/prevenção & controle , Sistema ABO de Grupos Sanguíneos/imunologia , Análise Custo-Benefício , Hemaglutininas/sangue , Humanos , Transfusão de Plaquetas/economia
8.
Phys Rev Lett ; 121(14): 142701, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339438

RESUMO

The ^{12}C(α,γ)^{16}O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced α width, γ_{11}, of the bound 1^{-} level in ^{16}O is particularly important to determine the cross section. The magnitude of γ_{11} is determined via sub-Coulomb α-transfer reactions or the ß-delayed α decay of ^{16}N, but the latter approach is presently hampered by the lack of sufficiently precise data on the ß-decay branching ratios. Here we report improved branching ratios for the bound 1^{-} level [b_{ß,11}=(5.02±0.10)×10^{-2}] and for ß-delayed α emission [b_{ßα}=(1.59±0.06)×10^{-5}]. Our value for b_{ßα} is 33% larger than previously held, leading to a substantial increase in γ_{11}. Our revised value for γ_{11} is in good agreement with the value obtained in α-transfer studies and the weighted average of the two gives a robust and precise determination of γ_{11}, which provides significantly improved constraints on the ^{12}C(α,γ) cross section in the energy range relevant to hydrostatic He burning.

9.
Phys Rev Lett ; 118(16): 162501, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28474951

RESUMO

Prompt γ-ray spectroscopy of the neutron-rich ^{96}Kr, produced in transfer- and fusion-induced fission reactions, has been performed using the combination of the Advanced Gamma Tracking Array and the VAMOS++ spectrometer. A second excited state, assigned to J^{π}=4^{+}, is observed for the first time, and a previously reported level energy of the first 2^{+} excited state is confirmed. The measured energy ratio R_{4/2}=E(4^{+})/E(2^{+})=2.12(1) indicates that this nucleus does not show a well-developed collectivity contrary to that seen in heavier N=60 isotones. This new measurement highlights an abrupt transition of the degree of collectivity as a function of the proton number at Z=36, of similar amplitude to that observed at N=60 at higher Z values. A possible reason for this abrupt transition could be related to the insufficient proton excitations in the g_{9/2}, d_{5/2}, and s_{1/2} orbitals to generate strong quadrupole correlations or to the coexistence of competing different shapes. An unexpected continuous decrease of R_{4/2} as a function of the neutron number up to N=60 is also evidenced. This measurement establishes the Kr isotopic chain as the low-Z boundary of the island of deformation for N=60 isotones. A comparison with available theoretical predictions using different beyond mean-field approaches shows that these models fail to reproduce the abrupt transitions at N=60 and Z=36.

10.
Stat Med ; 36(28): 4548-4569, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-28664564

RESUMO

The LIPGENE-SU.VI.MAX study, like many others, recorded high-dimensional continuous phenotypic data and categorical genotypic data. LIPGENE-SU.VI.MAX focuses on the need to account for both phenotypic and genetic factors when studying the metabolic syndrome (MetS), a complex disorder that can lead to higher risk of type 2 diabetes and cardiovascular disease. Interest lies in clustering the LIPGENE-SU.VI.MAX participants into homogeneous groups or sub-phenotypes, by jointly considering their phenotypic and genotypic data, and in determining which variables are discriminatory. A novel latent variable model that elegantly accommodates high dimensional, mixed data is developed to cluster LIPGENE-SU.VI.MAX participants using a Bayesian finite mixture model. A computationally efficient variable selection algorithm is incorporated, estimation is via a Gibbs sampling algorithm and an approximate BIC-MCMC criterion is developed to select the optimal model. Two clusters or sub-phenotypes ('healthy' and 'at risk') are uncovered. A small subset of variables is deemed discriminatory, which notably includes phenotypic and genotypic variables, highlighting the need to jointly consider both factors. Further, 7 years after the LIPGENE-SU.VI.MAX data were collected, participants underwent further analysis to diagnose presence or absence of the MetS. The two uncovered sub-phenotypes strongly correspond to the 7-year follow-up disease classification, highlighting the role of phenotypic and genotypic factors in the MetS and emphasising the potential utility of the clustering approach in early screening. Additionally, the ability of the proposed approach to define the uncertainty in sub-phenotype membership at the participant level is synonymous with the concepts of precision medicine and nutrition. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Análise por Conglomerados , Análise Fatorial , Genótipo , Fenótipo , Algoritmos , Teorema de Bayes , União Europeia , Humanos , Cadeias de Markov , Síndrome Metabólica/classificação , Síndrome Metabólica/genética , Método de Monte Carlo , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Risco
11.
Reprod Fertil Dev ; 29(4): 658-669, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26511586

RESUMO

The aims of the present study were to: (1) characterise the metabolome of follicular fluid and serum in dairy cows with similar genetic merit for milk production but with extremes of good (Fert+) or poor (Fert-) genetic merit for fertility; and (2) identify potential biomarkers of dairy cow fertility. Follicular fluid from the first wave dominant follicle and serum were collected on Day 7 of the oestrous cycle. The most pronounced effect of genotype was noted in the serum, where the abundance of total polyunsaturated fatty acids and n-6 polyunsaturated fatty acids was greater in Fert+ cows, and the abundance of total saturated fatty acids was greater in Fert- cows. The abundance of nine fatty acids (arachidic acid, heneicosanoic acid, myristic acid, behenic acid, myristoleic acid, heptadecenoic acid, cis-11-eicosanoic acid, nervonic acid and γ-linolenic acid) in follicular fluid was affected by genotype. Concentrations of cysteine, leucine, ornithine, proline and tyrosine in follicular fluid, and asparagine, creatinine, cysteine, methionine, proline and valine in serum, were also affected by genotype. Receiver operating characteristic curve analysis indicated that the follicular fluid and serum fatty acids and follicular fluid amino acids that were significantly affected by genotype were highly predictive of fertility genotype.


Assuntos
Ácidos Graxos/metabolismo , Fertilidade/genética , Líquido Folicular/metabolismo , Animais , Bovinos , Ciclo Estral/metabolismo , Feminino , Genótipo , Lactação/metabolismo , Metaboloma , Leite , Folículo Ovariano/metabolismo
12.
Am J Transplant ; 16(7): 2187-95, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26790369

RESUMO

Short-term outcomes of kidney transplantation have improved dramatically, but chronic rejection and regimen-related toxicity continue to compromise overall patient outcomes. Development of regulatory T cells (Tregs) as a means to decrease alloresponsiveness and limit the need for pharmacologic immunosuppression is an active area of preclinical and clinical investigation. Nevertheless, the immunomodulatory effects of end-stage renal disease on the efficacy of various strategies to generate and expand recipient Tregs for kidney transplantation are incompletely characterized. In this study, we show that Tregs can be successfully generated from either freshly isolated or previously cryopreserved uremic recipient (responder) and healthy donor (stimulator) peripheral blood mononuclear cells using the strategy of ex vivo costimulatory blockade with belatacept during mixed lymphocyte culture. Moreover, these Tregs maintain a CD3(+) CD4(+) CD25(+) CD127(lo) surface phenotype, high levels of intracellular FOXP3 and significant demethylation of the FOXP3 Treg-specific demethylation region on allorestimulation with donor stimulator cells. These data support evaluation of this simple, brief Treg production strategy in clinical trials of mismatched kidney transplantation.


Assuntos
Isoantígenos/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Leucócitos Mononucleares/imunologia , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante/imunologia , Abatacepte/imunologia , Adulto , Idoso , Feminino , Seguimentos , Fatores de Transcrição Forkhead/imunologia , Taxa de Filtração Glomerular , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Conduta Expectante
13.
Phys Rev Lett ; 117(22): 222302, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925748

RESUMO

The ^{54}Fe nucleus was populated from a ^{56}Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10^{+} metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the ^{56}Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of ^{54}Fe, suggesting that it was populated via the decay of the Δ^{0} resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10^{+} metastable state in ^{54}Fe is a consequence of the quark structure of the nucleons.

14.
Am J Transplant ; 14(2): 305-18, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24410845

RESUMO

Allostimulation with concurrent costimulatory blockade induces alloantigen-specific hyporesponsiveness in responder T cells ("alloanergization"). Alloanergized responder cells also acquire alloantigen-specific suppressive activity, suggesting this strategy induces active immune tolerance. While this acquired suppressive activity is mediated primarily by CD4(+) FOXP3(+) cells, other cells, most notably CD8(+) suppressor cells, have also been shown to ameliorate human alloresponses. To determine whether alloanergization expands CD8(+) cells with allosuppressive phenotype and function, we used mixed lymphocyte cultures in which costimulatory blockade was provided by belatacept, an FDA-approved, second-generation CTLA-4-immunoglobulin fusion protein that blocks CD28-mediated costimulation, as an in vitro model of HLA-mismatched transplantation. This strategy resulted in an eightfold expansion of CD8(+) CD28(-) T cells which potently and specifically suppressed alloresponses of both CD4(+) and CD8(+) T cells without reducing the frequency of a range of functional pathogen-specific T cells. This CD8-mediated allosuppression primarily required cell-cell contact. In addition, we observed expansion of CD8(+) CD28(-) T cells in vivo in patients undergoing alloanergized HLA-mismatched bone marrow transplantation. Use of costimulatory blockade-mediated alloanergization to expand allospecific CD8(+) CD28(-) suppressor cells merits exploration as an approach to inducing or supporting immune tolerance to alloantigens after allogeneic transplantation.


Assuntos
Antígenos CD28/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Anergia Clonal/imunologia , Tolerância Imunológica/imunologia , Isoantígenos/imunologia , Leucócitos Mononucleares/imunologia , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Citometria de Fluxo , Humanos , Ativação Linfocitária , Transplante Homólogo
15.
Nutr Metab Cardiovasc Dis ; 24(9): 996-1003, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24875672

RESUMO

BACKGROUND AND AIMS: Consumption of foods that modulate inflammatory stress in genetically-prone individuals may influence development of cardiometabolic diseases. Isoflavones in soy-derived foods function as phytoestrogens, have antioxidant and anti-inflammatory activity, inhibit protein-tyrosine kinase activity, and may be atheroprotective. We examined the relationship between soy food consumption and inflammatory responses to endotoxemia, postprandial responses to oral lipid tolerance test (OLTT), and insulin sensitivity from frequently sampled intravenous tolerance tests (FSIGTT). METHODS AND RESULTS: We administered low-dose endotoxin (LPS 1 ng/kg) to induce transient endotoxemia in young, healthy volunteers (N = 215) of African (AA), and European (EA) ancestry as part of the GENE Study. We further supported these findings in two independent samples: the MECHE Study and NHANES. Soy food consumption was a significant predictor of peak cytokine response following LPS. Individuals with moderate-high (>1.48 mg/day, N = 65) vs. low-no (<1.48 mg/day, N = 150) isoflavone consumption had significantly higher tumor necrosis factor alpha (TNFα) post-LPS (AUC, P = 0.009). Further, high-isoflavone consumers were protected against inflammation-induced decline in insulin sensitivity (SI) in GENE. We observed significant differences by soy consumption in the interferon gamma (IFNγ) response to OLTT, and the insulin response to OGTT in MECHE, as well as significantly lower fasting insulin, and 2-hour glucose post-OGTT in EA NHANES subjects. CONCLUSION: We demonstrate that soy consumption may influence inflammatory and metabolic responses. In research of nutritional exposures, measuring evoked phenotypes may be more informative than describing resting characteristics. The GENE Study was registered under NCT00953667 and the MECHE Study under NCT01172951, both at clinicaltrials.gov.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Inflamação/prevenção & controle , Isoflavonas/administração & dosagem , Adolescente , Adulto , Negro ou Afro-Americano , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Glicemia/metabolismo , Índice de Massa Corporal , Feminino , Voluntários Saudáveis , Homeostase/efeitos dos fármacos , Humanos , Resistência à Insulina , Modelos Lineares , Lipopolissacarídeos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fitoestrógenos/administração & dosagem , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Alimentos de Soja/análise , Fator de Necrose Tumoral alfa/metabolismo , População Branca , Adulto Jovem
16.
IEEE Trans Biomed Eng ; 71(4): 1151-1160, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37910420

RESUMO

OBJECTIVE: To enhance visualization in pediatric Otolaryngology middle ear surgeries and reduce mastoidectomy instances, we introduce a novel Articulating Chip-on-Tip Endoscope (ACoT Endo). METHODS: The ACoT Endo incorporates a cable-driven distal end camera and off-the-shelf Chip-on-Tip camera to improve visualization. We compared its capabilities with standard endoscopes, evaluating its bending capacity (70 ° ± 2 °) and center axis rotation (360 °). To test the overall functionality of this device, a Mock Ear was created to simulate the anatomy of the human ear, and the ACoT Endo's ability to be used in this cavity is compared to a standard 0 ° Karl Storz endoscope through tests with the Mock Ear and respective endoscopes. RESULTS: The ACoT Endo accurately captured surgical details similar to standard endoscopes in the ENT field. Compared to the 0 ° Karl Storz endoscope, the ACoT Endo demonstrated an increased field of view by approximately 69% and captured area by approximately 249%. ACot Endo allowed the surgeon to effortlessly articulate the camera with the rotation of a finger, while an excision tool was inserted in the middle ear, a procedure that is currently extremely difficult with standard endoscopes. CONCLUSION: The ACoT Endo's dynamic viewing angle and Chip-on-Tip camera enable unparalleled surgical visualization within the middle ear using a single endoscope, offering potential benefits in Otolaryngology procedures. SIGNIFICANCE: By reducing the need for invasive mastoidectomies and providing better visualization tools, the ACoT Endo has significant potential to improve outcomes and safety in pediatric middle ear surgeries.


Assuntos
Orelha Média , Endoscópios , Humanos , Criança , Orelha Média/cirurgia , Endoscopia
17.
Reproduction ; 146(4): 389-95, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23886995

RESUMO

The use of metabolomic based techniques to aid oocyte and embryo selection has gained attention in recent years. Previous work from our laboratory has demonstrated that the (1)H NMR-based metabolic profile of follicular fluid correlates with oocyte developmental potential. Patients undergoing IVF at the Merrion Fertility Clinic had follicular fluid collected at the time of oocyte retrieval. The fatty acid composition of follicular fluid from follicles where oocytes fertilised and developed into multi-cell embryos (n=15) and from oocytes that fertilised normally but failed to cleave (n=9) (cleaved vs non-cleaved) was compared. Statistical analysis was performed on the data using univariate and multivariate techniques. Analysis of the fatty acid composition revealed that there were nine fatty acids significantly different between follicular fluid from the cleaved and the non-cleaved sample groups. Of particular interest were the higher concentration of total saturated (P=0.03) and the lower concentration of total polyunsaturated fatty acids in the non-cleaved sample group (P=0.001). Random forest classification models were used to predict successful cleavage in follicular fluid samples producing models with errors rates of <10%. Receiver operating characteristic analysis demonstrated that the model had good predictability with an area under the curve of 0.96. The panel of fatty acid biomarkers identified in this study indicates that the fatty acid composition of follicular fluid may be more predictive in comparison to other previously identified biomarkers. Following validation in a larger cohort, these biomarkers may have the potential to be used in fertility clinics to aid the selection of oocytes in the future.


Assuntos
Biomarcadores/metabolismo , Ácidos Graxos/metabolismo , Líquido Folicular/metabolismo , Metabolômica , Oócitos/citologia , Oócitos/metabolismo , Adulto , Área Sob a Curva , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética , Curva ROC
18.
Insect Mol Biol ; 21(5): 510-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22831171

RESUMO

Molecular interactions between symbiotic bacteria and their animal hosts are, as yet, poorly understood. The most widespread bacterial endosymbiont, Wolbachia pipientis, occurs in high density in testes of infected Drosophila simulans and causes cytoplasmic incompatibility (CI), a form of male-derived zygotic lethality. Wolbachia grow and divide within host vacuoles that generate reactive oxygen species (ROS), which in turn stimulate the up-regulation of antioxidant enzymes. These enzymes appear to protect the host from ROS-mediated damage, as there is no obvious fitness cost to Drosophila carrying Wolbachia infections. We have now determined that DNA from Wolbachia-infected mosquito Aedes albopictus (Aa23) cells shows a higher amount of the base 8-oxo-deoxyguanosine, a marker of oxidative DNA damage, than DNA from uninfected cells, and that Wolbachia infection in D. simulans is associated with an increase in DNA strand breaks in meiotic spermatocytes. Feeding exogenous antioxidants to male and female D. simulans dramatically increased Wolbachia numbers with no obvious effects on host fitness. These results suggest that ROS-induced DNA damage in sperm nuclei may contribute to the modification characteristic of CI expression in Wolbachia-infected males and that Wolbachia density is sensitive to redox balance in these flies.


Assuntos
Dano ao DNA , Drosophila/microbiologia , Estresse Oxidativo , Espermatogênese , Wolbachia/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Animais , Antioxidantes , Linhagem Celular , Ensaio Cometa , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análise , Drosophila/metabolismo , Feminino , Glutationa , Homeostase , Masculino , Espermatócitos/metabolismo , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Testículo/microbiologia
19.
Br J Dermatol ; 166(2): 279-87, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21967555

RESUMO

BACKGROUND: Patients with papulopustular rosacea (PPR) frequently complain of dry, sensitive skin. We have previously demonstrated that patients with PPR have reduced skin surface hydration levels in the presence of normal sebum casual levels, suggesting that it may be the quality and not the quantity of sebum that plays a role in PPR. OBJECTIVES: To compare the sebaceous fatty acid composition of patients with PPR to that of controls with normal facial skin. METHODS: The sebaceous fatty acid composition of 25 patients with PPR and 24 age- and sex-matched controls was analysed by gas chromatography - mass spectrometry. Results Myristic acid (C14:0) was present in greater concentrations in PPR sebum, while the long chain saturated fatty acids arachidic acid (C20:0), behenic acid (C22:0), tricosanoic acid (C23:0) and lignoceric acid (C24:0) as well as the monounsaturated fatty acid cis-11-eicosanoic acid (C20:1) were present in the sebum of patients with PPR in lesser concentrations as compared with controls. CONCLUSIONS: There is increasing evidence that sebaceous fatty acids play a role in the maintenance of skin barrier integrity. We have shown for the first time that patients with PPR have an abnormal sebaceous fatty acid composition, with reduced levels of long chain saturated fatty acids. These new findings may have therapeutic implications for the development of sebum-modifying nonantibiotic treatments for patients with PPR.


Assuntos
Ácidos Graxos/metabolismo , Rosácea/metabolismo , Glândulas Sebáceas/química , Sebo/química , Adulto , Idoso , Estudos de Casos e Controles , Fármacos Dermatológicos/uso terapêutico , Ácidos Graxos/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Minociclina/uso terapêutico , Rosácea/tratamento farmacológico
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