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1.
Cell ; 184(18): 4713-4733.e22, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34352228

RESUMO

SARS-CoV-2 infection can cause severe respiratory COVID-19. However, many individuals present with isolated upper respiratory symptoms, suggesting potential to constrain viral pathology to the nasopharynx. Which cells SARS-CoV-2 primarily targets and how infection influences the respiratory epithelium remains incompletely understood. We performed scRNA-seq on nasopharyngeal swabs from 58 healthy and COVID-19 participants. During COVID-19, we observe expansion of secretory, loss of ciliated, and epithelial cell repopulation via deuterosomal cell expansion. In mild and moderate COVID-19, epithelial cells express anti-viral/interferon-responsive genes, while cells in severe COVID-19 have muted anti-viral responses despite equivalent viral loads. SARS-CoV-2 RNA+ host-target cells are highly heterogenous, including developing ciliated, interferon-responsive ciliated, AZGP1high goblet, and KRT13+ "hillock"-like cells, and we identify genes associated with susceptibility, resistance, or infection response. Our study defines protective and detrimental responses to SARS-CoV-2, the direct viral targets of infection, and suggests that failed nasal epithelial anti-viral immunity may underlie and precede severe COVID-19.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Imunidade , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença , Adulto , Idoso , Efeito Espectador , COVID-19/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/patologia , Nasofaringe/virologia , RNA Viral/análise , RNA Viral/genética , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Transcrição Gênica , Carga Viral
2.
J Neurosci ; 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35610051

RESUMO

The robust, reciprocal anatomical connections between the cerebellum and contralateral sensorimotor cerebral hemisphere underscores the strong physiological interdependence between these two regions in relation to human behavior. Previous studies have shown that damage to sensorimotor cortex can result in a lasting reduction of cerebellar metabolism, the magnitude of which has been linked to poor rehabilitative outcomes. A better understanding of movement-related cerebellar physiology as well as cortico-cerebellar coherence (CCC) in the chronic, post-stroke state may be key to developing novel neuromodulatory techniques that promote upper limb motor rehabilitation. As a part of the first in-human phase-I trial investigating the effects of deep brain stimulation of the cerebellar dentate nucleus (DN) on chronic, post-stroke motor rehabilitation, we collected invasive recordings from DN and scalp EEG in subjects (both sexes) with middle cerebral artery stroke during a visuo-motor tracking task. We investigated the excitability of ipsilesional cortex, DN and the their interaction as a function of motor impairment and performance. Our results indicate that 1) event-related oscillations in the ipsilesional cortex and DN were significantly correlated at movement onset in the low-ß band, with moderately and severely impaired subjects showing desynchronization and synchronization, respectively. 2) Significant CCC was observed during isometric 'hold' period in the low-ß band, which was critical for maintaining task accuracy. Our findings support a strong coupling between ipsilesional cortex and DN in the low-ß band during motor control across all impairment levels which encourages the exploitation of the cerebello-thalamo-cortical pathway as a neuromodulation target to promote rehabilitation.Significance Statement:Cerebral infarct due to stroke can lead to lasting reduction in cerebellar metabolism resulting in poor rehabilitative outcomes. Thorough investigation of the cerebellar electrophysiology as well as cortico-cerebellar connectivity in humans that could provide key insights to facilitate development of novel neuromodulatory technologies, has been lacking. As a part of the first in-human phase-I trial investigating deep brain stimulation of the cerebellar dentate nucleus (DN) for chronic, post-stroke motor rehabilitation, we collected invasive recordings from DN and scalp EEG while stroke patients performed a motor task. Our data indicate strong coupling between ipsilesional sensorimotor cortex and DN in the low-ß band across all impairment levels encouraging the exploration of electrical stimulation of the DN.

3.
Int J Mol Sci ; 24(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37762483

RESUMO

Cotton (Gossypium spp.) is the primary source of natural textile fiber in the U.S. and a major crop in the Southeastern U.S. Despite constant efforts to increase the cotton fiber yield, the yield gain has stagnated. Therefore, we undertook a novel approach to improve the cotton fiber yield by altering its growth habit from perennial to annual. In this effort, we identified genotypes with high-expression alleles of five floral induction and meristem identity genes (FT, SOC1, FUL, LFY, and AP1) from an Upland cotton mini-core collection and crossed them in various combinations to develop cotton lines with annual growth habit, optimal flowering time, and enhanced productivity. To facilitate the characterization of genotypes with the desired combinations of stacked alleles, we identified molecular markers associated with the gene expression traits via genome-wide association analysis using a 63 K SNP Array. Over 14,500 SNPs showed polymorphism and were used for association analysis. A total of 396 markers showed associations with expression traits. Of these 396 markers, 159 were mapped to genes, 50 to untranslated regions, and 187 to random genomic regions. Biased genomic distribution of associated markers was observed where more trait-associated markers mapped to the cotton D sub-genome. Many quantitative trait loci coincided at specific genomic regions. This observation has implications as these traits could be bred together. The analysis also allowed the identification of candidate regulators of the expression patterns of these floral induction and meristem identity genes whose functions will be validated.

4.
Wound Repair Regen ; 30(6): 636-651, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35212086

RESUMO

Xenopus laevis tadpoles can regenerate functional tails, containing the spinal cord, notochord, muscle, fin, blood vessels and nerves, except for a brief refractory period at around 1 week of age. At this stage, amputation of the tadpole's tail may either result in scarless wound healing or the activation of a regeneration programme, which replaces the lost tissues. We recently demonstrated a link between bacterial lipopolysaccharides and successful tail regeneration in refractory stage tadpoles and proposed that this could result from lipopolysaccharides binding to Toll-like receptor 4 (TLR4). Here, we have used 16S rRNA sequencing to show that the tadpole skin microbiome is highly variable between sibships and that the community can be altered by raising embryos in the antibiotic gentamicin. Six Gram-negative genera, including Delftia and Chryseobacterium, were over-represented in tadpoles that underwent tail regeneration. Lipopolysaccharides purified from a commensal Chryseobacterium spp. XDS4, an exogenous Delftia spp. or Escherichia coli, could significantly increase the number of antibiotic-raised tadpoles that attempted regeneration. Conversely, the quality of regeneration was impaired in native-raised tadpoles exposed to the antagonistic lipopolysaccharide of Rhodobacter sphaeroides. Editing TLR4 using CRISPR/Cas9 also reduced regeneration quality, but not quantity, at the level of the cohort. However, we found that the editing level of individual tadpoles was a poor predictor of regenerative outcome. In conclusion, our results suggest that variable regeneration in refractory stage tadpoles depends at least in part on the skin microbiome and lipopolysaccharide signalling, but that signalling via TLR4 cannot account for all of this effect.


Assuntos
Lipopolissacarídeos , Microbiota , Animais , Antibacterianos , Larva/fisiologia , Lipopolissacarídeos/farmacologia , RNA Ribossômico 16S , Receptor 4 Toll-Like/metabolismo , Cicatrização , Xenopus laevis/genética , Xenopus laevis/metabolismo
5.
Nature ; 534(7606): 222-6, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279216

RESUMO

Quantum mechanics can help to solve complex problems in physics and chemistry, provided they can be programmed in a physical device. In adiabatic quantum computing, a system is slowly evolved from the ground state of a simple initial Hamiltonian to a final Hamiltonian that encodes a computational problem. The appeal of this approach lies in the combination of simplicity and generality; in principle, any problem can be encoded. In practice, applications are restricted by limited connectivity, available interactions and noise. A complementary approach is digital quantum computing, which enables the construction of arbitrary interactions and is compatible with error correction, but uses quantum circuit algorithms that are problem-specific. Here we combine the advantages of both approaches by implementing digitized adiabatic quantum computing in a superconducting system. We tomographically probe the system during the digitized evolution and explore the scaling of errors with system size. We then let the full system find the solution to random instances of the one-dimensional Ising problem as well as problem Hamiltonians that involve more complex interactions. This digital quantum simulation of the adiabatic algorithm consists of up to nine qubits and up to 1,000 quantum logic gates. The demonstration of digitized adiabatic quantum computing in the solid state opens a path to synthesizing long-range correlations and solving complex computational problems. When combined with fault-tolerance, our approach becomes a general-purpose algorithm that is scalable.

6.
Am J Gastroenterol ; 116(8): 1638-1645, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34047305

RESUMO

INTRODUCTION: Proton pump inhibitor (PPI) use was recently reported to be associated with increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and worse clinical outcomes. The underlying mechanism(s) for this association are unclear. METHODS: We performed a prospective study of hospitalized coronavirus disease 2019 (COVID-19) patients and COVID-negative controls to understand how PPI use may affect angiotensin-converting enzyme 2 (ACE2) expression and stool SARS-CoV-2 RNA. Analysis of a retrospective cohort of hospitalized patients with COVID-19 from March 15, 2020 to August 15, 2020 in 6 hospitals was performed to evaluate the association of PPI use and mortality. Covariates with clinical relevance to COVID-19 outcomes were included to determine predictors of in-hospital mortality. RESULTS: Control PPI users had higher salivary ACE2 mRNA levels than nonusers, 2.39 ± 1.15 vs 1.22 ± 0.92 (P = 0.02), respectively. Salivary ACE2 levels and stool SARS-CoV-2 RNA detection rates were comparable between users and nonusers of PPI. In 694 hospitalized patients with COVID-19 (age = 58 years, 46% men, and 65% black), mortality rate in PPI users and nonusers was 30% (68/227) vs 12.1% (53/439), respectively. Predictors of mortality by logistic regression were PPI use (adjusted odds ratio [aOR] = 2.72, P < 0.001), age (aOR = 1.66 per decade, P < 0.001), race (aOR = 3.03, P = 0.002), cancer (aOR = 2.22, P = 0.008), and diabetes (aOR = 1.95, P = 0.003). The PPI-associated mortality risk was higher in black patients (aOR = 4.16, 95% confidence interval: 2.28-7.59) than others (aOR = 1.62, 95% confidence interval: 0.82-3.19, P = 0.04 for interaction). DISCUSSION: COVID-negative PPI users had higher salivary ACE2 expression. PPI use was associated with increased mortality risk in patients with COVID-19, particularly African Americans.


Assuntos
Enzima de Conversão de Angiotensina 2/sangue , COVID-19/sangue , COVID-19/mortalidade , Inibidores da Bomba de Prótons/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco
7.
Cancer Causes Control ; 32(5): 473-482, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33742258

RESUMO

PURPOSE: Community-based participatory research (CBPR) is a collaborative partnership approach that leverages the strengths of academic-community groups to address local problems. CBPR emphasizes equity (e.g., co-learning, power-sharing, participatory decision-making) among groups to achieve goals and promote sustainability. This study examines group dynamics, and their influence on achieving shared goals, within a CBPR-guided partnership established to improve breast and prostate cancer outcomes among underserved African American communities in St. Louis, Missouri. METHODS: We conducted in-person, semi-structured interviews with key academic and community informants and surveyed via email community collaborators involved in outreach activities. Interviews were audiotaped, transcribed, and independently coded by two authors using an iterative, open-coding process to identify major themes. Surveys were summarized using similar coding criteria for open-ended responses and descriptive statistics for discrete responses. Using a grounded theory approach, we summarized and compared themes from each data source to identify similarities and differences and triangulated results to generate overarching thematic findings. RESULTS: Participants described benefits from the partnership (funding; clinical, public health and evaluation expertise; training and networking opportunities) and found beneficial ways to leverage the partners' strengths in collaborating Participants expressed long-term commitment to sustaining the partnership and building capacity to address cancer disparities, but faced challenges related to power-sharing and participatory decision-making. CONCLUSIONS: Using CBPR to address cancer disparities is an effective approach to capacity-building and achieving shared goals. By evaluating the structures and processes within CBPR collaborations through the lens of equity, partners may identify and address challenges that threaten long-term partnership sustainability.


Assuntos
Negro ou Afro-Americano , Neoplasias da Mama/terapia , Neoplasias da Próstata/terapia , Fortalecimento Institucional , Pesquisa Participativa Baseada na Comunidade/métodos , Relações Comunidade-Instituição , Estudos Transversais , Feminino , Humanos , Masculino , Projetos de Pesquisa
8.
Nature ; 519(7541): 66-9, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25739628

RESUMO

Quantum computing becomes viable when a quantum state can be protected from environment-induced error. If quantum bits (qubits) are sufficiently reliable, errors are sparse and quantum error correction (QEC) is capable of identifying and correcting them. Adding more qubits improves the preservation of states by guaranteeing that increasingly larger clusters of errors will not cause logical failure-a key requirement for large-scale systems. Using QEC to extend the qubit lifetime remains one of the outstanding experimental challenges in quantum computing. Here we report the protection of classical states from environmental bit-flip errors and demonstrate the suppression of these errors with increasing system size. We use a linear array of nine qubits, which is a natural step towards the two-dimensional surface code QEC scheme, and track errors as they occur by repeatedly performing projective quantum non-demolition parity measurements. Relative to a single physical qubit, we reduce the failure rate in retrieving an input state by a factor of 2.7 when using five of our nine qubits and by a factor of 8.5 when using all nine qubits after eight cycles. Additionally, we tomographically verify preservation of the non-classical Greenberger-Horne-Zeilinger state. The successful suppression of environment-induced errors will motivate further research into the many challenges associated with building a large-scale superconducting quantum computer.

9.
Am J Otolaryngol ; 42(5): 103146, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34171529

RESUMO

PURPOSE: 30-day hospital readmissions after head and neck cancer surgery continue to be a significant source of patient harm and healthcare expenditure. While there is substantial data in the literature assessing predictive factors for readmissions after head and neck cancer surgery, there are a paucity of studies which attempt to understand if such readmissions are preventable. The goal of this paper is to determine factors associated with 30-day hospital readmissions after head and neck cancer surgery and to understand if these readmissions were preventable. MATERIALS AND METHODS: Retrospective review from a single academic tertiary care center. Patients readmitted within 30 days after undergoing surgery for cancers of the head and neck between 2015 and 2018 were identified. RESULTS: Over a 3-year period, 26 patients undergoing resection with or without reconstruction of head and neck cancers were readmitted to the hospital within 30 days of discharge. There were 15 (58%) men and 11 (42%) women with a mean age of 68 years (SD 14 years). Twenty-one (81%) patients had squamous cell carcinoma and 13 (50%) had a primary site in the oral cavity. Thirteen (50%) had undergone free or regional flap reconstruction. The indication for readmission was related to the surgical wound in 19 (73%) and to medical complications in 7 (27%). Each case was categorized as "possibly preventable" versus "uncertain if preventable" based on whether a reasonable and feasible change in management may have prevented readmission. Six (23%) readmissions were deemed possibly preventable. Four were related to the surgical wound where initial free or regional flaps may have prevented complication. Two were medical complications that may have benefited from longer inpatient observation. CONCLUSIONS: For a subset of patients readmitted within 30 days of head and neck cancer surgery, a reasonable and feasible change in management may have prevented their hospital readmission. The significance of better understanding this patient population is underscored by the high mortality rate.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Readmissão do Paciente , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Previsões , Gastos em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Readmissão do Paciente/economia , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/prevenção & controle , Procedimentos de Cirurgia Plástica , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica/prevenção & controle
10.
Nature ; 515(7526): 241-4, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25391961

RESUMO

Topology, with its abstract mathematical constructs, often manifests itself in physics and has a pivotal role in our understanding of natural phenomena. Notably, the discovery of topological phases in condensed-matter systems has changed the modern conception of phases of matter. The global nature of topological ordering, however, makes direct experimental probing an outstanding challenge. Present experimental tools are mainly indirect and, as a result, are inadequate for studying the topology of physical systems at a fundamental level. Here we employ the exquisite control afforded by state-of-the-art superconducting quantum circuits to investigate topological properties of various quantum systems. The essence of our approach is to infer geometric curvature by measuring the deflection of quantum trajectories in the curved space of the Hamiltonian. Topological properties are then revealed by integrating the curvature over closed surfaces, a quantum analogue of the Gauss-Bonnet theorem. We benchmark our technique by investigating basic topological concepts of the historically important Haldane model after mapping the momentum space of this condensed-matter model to the parameter space of a single-qubit Hamiltonian. In addition to constructing the topological phase diagram, we are able to visualize the microscopic spin texture of the associated states and their evolution across a topological phase transition. Going beyond non-interacting systems, we demonstrate the power of our method by studying topology in an interacting quantum system. This required a new qubit architecture that allows for simultaneous control over every term in a two-qubit Hamiltonian. By exploring the parameter space of this Hamiltonian, we discover the emergence of an interaction-induced topological phase. Our work establishes a powerful, generalizable experimental platform to study topological phenomena in quantum systems.

11.
Nature ; 508(7497): 500-3, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24759412

RESUMO

A quantum computer can solve hard problems, such as prime factoring, database searching and quantum simulation, at the cost of needing to protect fragile quantum states from error. Quantum error correction provides this protection by distributing a logical state among many physical quantum bits (qubits) by means of quantum entanglement. Superconductivity is a useful phenomenon in this regard, because it allows the construction of large quantum circuits and is compatible with microfabrication. For superconducting qubits, the surface code approach to quantum computing is a natural choice for error correction, because it uses only nearest-neighbour coupling and rapidly cycled entangling gates. The gate fidelity requirements are modest: the per-step fidelity threshold is only about 99 per cent. Here we demonstrate a universal set of logic gates in a superconducting multi-qubit processor, achieving an average single-qubit gate fidelity of 99.92 per cent and a two-qubit gate fidelity of up to 99.4 per cent. This places Josephson quantum computing at the fault-tolerance threshold for surface code error correction. Our quantum processor is a first step towards the surface code, using five qubits arranged in a linear array with nearest-neighbour coupling. As a further demonstration, we construct a five-qubit Greenberger-Horne-Zeilinger state using the complete circuit and full set of gates. The results demonstrate that Josephson quantum computing is a high-fidelity technology, with a clear path to scaling up to large-scale, fault-tolerant quantum circuits.

12.
Foot Ankle Surg ; 26(3): 320-324, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31079958

RESUMO

BACKGROUND: Weightbearing images are important to the diagnosis of foot pathologies as are the three dimensional views available from CT and MRI. Standard three-dimensional imaging hardware, however, does not have a simple tool to obtain weightbearing images. The current research aimed to design, build and test a simple device to apply load in a horizontal bore imaging facility. METHODS: With the immediate need in hallux valgus studies, hallux valgus subjects were imaged using the new loading device, which could be easily transported and had no additional electronics. RESULTS: Testing showed that the usual angular measures of the foot (intermetatarsal and hallux valgus) replicated the results from the standard of care standing plain film results. With application of load, HV angle changed from 29.9° non-weightbearing to 32.2° weightbearing, while IM angle changed from nonweightbearing 15.8° to weightbearing 16.5°. CONCLUSION: The pedal-like device can provide weightbearing images in a horizontal bore MRI facility.


Assuntos
Hallux Valgus/diagnóstico , Imageamento por Ressonância Magnética/métodos , Suporte de Carga/fisiologia , Adulto , Idoso , Feminino , Hallux Valgus/fisiopatologia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Posição Ortostática
13.
Theor Appl Genet ; 132(4): 989-999, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30506522

RESUMO

KEY MESSAGE: Significant associations between candidate genes and six major cotton fiber quality traits were identified in a MAGIC population using GWAS and whole genome sequencing. Upland cotton (Gossypium hirsutum L.) is the world's major renewable source of fibers for textiles. To identify causative genetic variants that influence the major agronomic measures of cotton fiber quality, which are used to set discount or premium prices on each bale of cotton in the USA, we measured six fiber phenotypes from twelve environments, across three locations and 7 years. Our 550 recombinant inbred lines were derived from a multi-parent advanced generation intercross population and were whole-genome-sequenced at 3× coverage, along with the eleven parental cultivars at 20× coverage. The segregation of 473,517 single nucleotide polymorphisms (SNPs) in this population, including 7506 non-synonymous mutations, was combined with phenotypic data to identify seven highly significant fiber quality loci. At these loci, we found fourteen genes with non-synonymous SNPs. Among these loci, some had simple additive effects, while others were only important in a subset of the population. We observed additive effects for elongation and micronaire, when the three most significant loci for each trait were examined. In an informative subset where the major multi-trait locus on chromosome A07:72-Mb was fixed, we unmasked the identity of another significant fiber strength locus in gene Gh_D13G1792 on chromosome D13. The micronaire phenotype only revealed one highly significant genetic locus at one environmental location, demonstrating a significant genetic by environment component. These loci and candidate causative variant alleles will be useful to cotton breeders for marker-assisted selection with minimal linkage drag and potential biotechnological applications.


Assuntos
Fibra de Algodão/normas , Cruzamentos Genéticos , Loci Gênicos , Estudo de Associação Genômica Ampla , Genômica/métodos , Gossypium/genética , Sequenciamento Completo do Genoma , Cromossomos de Plantas/genética , Gossypium/anatomia & histologia , Endogamia , Anotação de Sequência Molecular , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
14.
J Dairy Sci ; 102(3): 2266-2274, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639005

RESUMO

The objective of this study was to evaluate the effects of supplementing xylanase on production performance, nutrient digestibility, and milk fatty acid profile in high-producing dairy cows consuming corn silage- or sorghum silage-based diets. Conventional corn (80,000 seeds/ha) and brown midrib forage sorghum (250,000 seeds/ha) were planted, harvested [34 and 32% of dry matter (DM), respectively], and ensiled for more than 10 mo. Four primiparous and 20 multiparous Holstein cows were randomly assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments and 19-d periods. Treatment diets consisted of (1) corn silage-based diet without xylanase, (2) corn silage-based diet with xylanase, (3) sorghum silage-based diet without xylanase, and (4) sorghum silage-based diet with xylanase. The xylanase product was supplemented at a rate of 1.5 g of product/kg of total DM. Corn silage had higher concentrations of starch (31.2 vs. 29.2%), slightly higher concentrations of crude protein (7.1 vs. 6.8%) and fat (3.7 vs. 3.2%), and lower concentrations of neutral detergent fiber (36.4 vs. 49.0%) and lignin (2.1 vs. 5.7%) than sorghum silage. Xylanase supplementation did not affect DM intake, milk yield, milk fat percentage and yield, milk protein percentage and yield, lactose percentage and yield, and 3.5% fat-corrected milk yield. Cows consuming corn silage-based diets consumed 13% more DM (28.8 vs. 25.5 kg/d) and produced 5% more milk (51.6 vs. 48.9 kg/d) than cows consuming sorghum silage-based diets. Milk from cows consuming sorghum silage-based diets had 16% greater fat concentrations (3.84 and 3.30%) than milk from cows consuming corn silage-based diets. This resulted in 8% greater fat yields (1.81 vs. 1.68 kg/d). Silage type did not affect milk protein and lactose concentrations. Xylanase supplementation did not affect nutrient digestibility. Cows consuming corn silage-based diets showed greater DM (77.3 vs. 73.5%), crude protein (78.0 vs. 72.4), and starch (99.2 vs. 96.5%) digestibilities than cows consuming sorghum silage-based diets. In conclusion, xylanase supplementation did not improve production performance when high-producing dairy cows were fed corn silage- or sorghum silage-based diets. In addition, production performance can be sustained by feeding sorghum silage in replacement of corn silage.


Assuntos
Bovinos/fisiologia , Digestão , Endo-1,4-beta-Xilanases/metabolismo , Lactação , Leite/química , Silagem/análise , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Endo-1,4-beta-Xilanases/administração & dosagem , Ácidos Graxos/metabolismo , Feminino , Nutrientes/fisiologia , Silagem/classificação , Sorghum/química , Zea mays/química
15.
Climacteric ; 21(1): 3-12, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29106307

RESUMO

BACKGROUND: The menopausal transition may have significant consequences for respiratory health, risk of chronic respiratory disease and management strategies. OBJECTIVE: To systematically summarize the literature regarding the impact of menopause status on respiratory health outcomes. METHODS: PubMed was searched systematically to identify population-based studies investigating the associations between menopause status and respiratory outcomes including asthma, chronic obstructive pulmonary disease (COPD), respiratory symptoms and lung function. RESULTS: Ten publications were identified for full review. Evidence on menopause and asthma was conflicting, while studies on COPD were scarce. The findings generally support an association between menopause and clinically significant reductions in lung function in a non-obstructive pattern. However, the effects of menopause are clouded by aging, menopausal hormone therapy use, and increased risk of metabolic syndrome during this period. CONCLUSIONS: As the global burden associated with respiratory conditions continues to rise, the need to understand the associations between menopause and respiratory health is essential to identify potentially modifiable risk factors for respiratory disease in adult women. More studies are needed to clarify the impact of menopause on obstructive lung disease.


Assuntos
Asma/fisiopatologia , Pulmão/fisiopatologia , Menopausa , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Feminino , Humanos , Fatores de Risco
16.
Thorax ; 72(3): 236-244, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27672121

RESUMO

RATIONALE: Evidence has suggested that exposure to environmental or microbial biodiversity in early life may impact subsequent lung function and allergic disease risk. OBJECTIVES: To investigate the influence of childhood living environment and biodiversity indicators on atopy, asthma and lung function in adulthood. METHODS AND MEASUREMENTS: The European Community Respiratory Health Survey II investigated ∼10 201 participants aged 26-54 years from 14 countries, including participants' place of upbringing (farm, rural environment or inner city) before age 5 years. A 'biodiversity score' was created based on childhood exposure to cats, dogs, day care, bedroom sharing and older siblings. Associations with lung function, bronchial hyper-responsiveness (BHR), allergic sensitisation, asthma and rhinitis were analysed. MAIN RESULTS: As compared with a city upbringing, those with early-life farm exposure had less atopic sensitisation (adjusted OR 0.46, 95% CI 0.37 to 0.58), atopic BHR (0.54 (0.35 to 0.83)), atopic asthma (0.47 (0.28 to 0.81)) and atopic rhinitis (0.43 (0.32 to 0.57)), but not non-atopic outcomes. Less pronounced protective effects were observed for rural environment exposures. Women with a farm upbringing had higher FEV1 (adjusted difference 110 mL (64 to 157)), independent of sensitisation and asthma. In an inner city environment, a higher biodiversity score was related to less allergic sensitisation. CONCLUSIONS: This is the first study to report beneficial effects of growing up on a farm on adult FEV1. Our study confirmed the beneficial effects of early farm life on sensitisation, asthma and rhinitis, and found a similar association for BHR. In persons with an urban upbringing, a higher biodiversity score predicted less allergic sensitisation, but to a lesser magnitude than a childhood farm environment.


Assuntos
Biodiversidade , Exposição Ambiental , Fazendas , Hipersensibilidade/epidemiologia , Adulto , Animais , Asma/epidemiologia , Gatos , Criança , Cuidado da Criança , Cães , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Fenótipo , Características de Residência , Testes de Função Respiratória , Rinite/epidemiologia , Irmãos
17.
Reproduction ; 154(6): 807-814, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28971891

RESUMO

It has been suggested that first embryo cleavage can be related with the embryonic-abembryonic axis at blastocyst stage in mice. Thus, cells of the 2-cell embryo might be already biased to form the inner cell mass or trophectoderm. This study was conducted to observe the possible effects of embryo biopsy on cell allocation patterns during embryo preimplantation in two different mouse strains and the effects of these patterns on further development. First, one blastomere of the 2-cell embryo was injected with a lipophilic tracer and cell allocation patterns were observed at blastocyst stage. Blastocysts were classified into orthogonal, deviant or random pattern. For the first experiment, embryos were biopsied at 8-cell stage and total cell counts (TCC) were annotated. Furthermore, non-biopsied blastocysts were transferred into foster mothers. Then, pups and their organs were weighed two weeks after birth. Random pattern was significantly recurrent (≈60%), against orthogonal (<22%) and deviant (<22%) patterns among groups. These patterns were not affected by biopsy procedure. However, TCC on deviant embryos were reduced after biopsy. Moreover, no differences were found between patterns for implantation rates, litter size, live offspring and organ weights (lungs, liver, pancreas and spleen). However, deviant pups presented heavier hearts and orthogonal pups presented lighter kidneys among the group. In conclusion, these results suggest that single blastomere removal does not disturb cell allocation patterns during pre-implantation. Nonetheless, the results suggest that embryos following different cell allocation patterns present different coping mechanisms against in vitro manipulations and further development might be altered.


Assuntos
Blastocisto/citologia , Blastômeros/citologia , Padronização Corporal , Animais , Animais Recém-Nascidos , Biópsia/efeitos adversos , Peso ao Nascer , Contagem de Células , Fase de Clivagem do Zigoto/citologia , Técnicas de Cultura Embrionária , Implantação do Embrião , Transferência Embrionária , Feminino , Masculino , Camundongos , Organogênese , Gravidez , Especificidade da Espécie
18.
Phys Rev Lett ; 118(5): 057702, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211704

RESUMO

By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around 2k_{B}T/h≈1 GHz, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a 1/f power law that matches the magnitude of the 1/f noise near 1 Hz. The antisymmetric component displays a 1/T dependence below 100 mK, providing dynamical evidence for a paramagnetic environment. Extrapolating the two-sided spectrum predicts the linewidth and reorganization energy of incoherent resonant tunneling between flux qubit wells.

19.
BJOG ; 124(6): 904-910, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27539893

RESUMO

OBJECTIVE: To evaluate the effect of ethnicity of women on the outcome of in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) treatment. DESIGN: Observational cohort study. SETTING: UK National Database. POPULATION: Data from 2000 to 2010 involving 38 709 women undergoing their first IVF/ICSI cycle were analysed. METHODS: Anonymous data were obtained from the Human Fertilization and Embryology Authority (HFEA), the statutory regulator of IVF and ICSI treatment in the UK. Data analysis was performed by regression analysis with adjustment for age, cause and type of infertility and treatment type (IVF or ICSI) to express results as odds ratio (OR) and 95% confidence intervals (95% CI). METHODS: Live birth rate per cycle of IVF or ICSI treatment. RESULTS: While white Irish (OR 0.73; 95% CI 0.60-0.90), Indian (0.85; 0.75-0.97), Bangladeshi (0.53: 0.33-0.85), Pakistani (0.68; 0.58-0.80), Black African (0.60; 0.51-0.72), and other non-Caucasian Asian (0.86; 0.73-0.99) had a significantly lower odds of live birth rates per fresh IVF/ICSI cycle than White British women, ethnic groups of White European (1.04; 0.96-1.13), Chinese (1.12; 0.77-1.64), Black Caribbean (0.76; 0.51-1.13), Middle Eastern (0.73; 0.51-1.04), Mediterranean European (1.18; 0.83-1.70) and Mixed race population (0.94; 0.73-1.19) had live birth rates that did not differ significantly. The cumulative live birth rates showed similar patterns across different ethnic groups. CONCLUSION: Ethnicity is a major determinant of IVF/ICSI treatment outcome as indicated by significantly lower live birth rates in some of the ethnic minority groups compared with white British women. TWEETABLE ABSTRACT: Ethnicity affects IVF outcome with lower live birth rates in some ethnic groups more than in white British.


Assuntos
Coeficiente de Natalidade/etnologia , Etnicidade/estatística & dados numéricos , Fertilização in vitro/estatística & dados numéricos , Nascido Vivo/etnologia , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado do Tratamento , Reino Unido
20.
Ultrasound Obstet Gynecol ; 49(5): 643-648, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27194568

RESUMO

OBJECTIVES: To determine the diagnostic accuracy of the double decidual sac sign (DDSS) for predicting an intrauterine pregnancy (IUP) prior to visualization of embryonic contents, using modern high-resolution transvaginal sonography (TVS). METHODS: The study was conducted following STARD guidelines and participants were recruited prospectively from Nurture Fertility, Nottingham, UK, following in-vitro fertilization/intracytoplasmic sperm injection treatment between 1 January 2015 and 31 October 2015. Women were excluded if there was no evidence of intrauterine fluid collection during the index test, a yolk sac or fetal pole was visible during the index test, no outcome data were available or pregnancy location could not be determined by the reference standard. The index test consisted of TVS at 32-34 days' gestation using a high-frequency transvaginal probe. Reference standard was TVS at 7 weeks' gestation. The outcome of interest was an IUP. RESULTS: A total of 67 intrauterine fluid collections were observed and included in the analysis, of which 61 exhibited the DDSS and 65 were proven to be IUPs. Two ectopic pregnancies were included, neither of which demonstrated the DDSS. The DDSS therefore had a sensitivity of 93.9% (95% CI, 85.0-98.3%), specificity of 100% (95% CI, 15.8-100%) and overall diagnostic accuracy of 94.0% (95% CI, 88.3-99.7%) for predicting an IUP. The negative likelihood ratio and positive and negative predictive values were 0.06 (95% CI, 0.02-0.16), 100% (95% CI, 94.1-100%) and 33.3% (95% CI, 4.3-77.7%), respectively. CONCLUSION: With modern high-resolution TVS, presence of the DDSS can be used to confirm accurately IUP location prior to sonographic visualization of embryonic contents, and therefore to exclude effectively ectopic pregnancy. Absence of the DDSS, however, does not preclude an IUP. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Saco Gestacional/diagnóstico por imagem , Gravidez Ectópica/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Imageamento Tridimensional , Guias de Prática Clínica como Assunto , Gravidez , Resultado da Gravidez , Curva ROC
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