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1.
Nature ; 578(7796): 568-571, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32103192

RESUMEN

Mass loss from the Antarctic Ice Sheet to the ocean has increased in recent decades, largely because the thinning of its floating ice shelves has allowed the outflow of grounded ice to accelerate1,2. Enhanced basal melting of the ice shelves is thought to be the ultimate driver of change2,3, motivating a recent focus on the processes that control ocean heat transport onto and across the seabed of the Antarctic continental shelf towards the ice4-6. However, the shoreward heat flux typically far exceeds that required to match observed melt rates2,7,8, suggesting that other critical controls exist. Here we show that the depth-independent (barotropic) component of the heat flow towards an ice shelf is blocked by the marked step shape of the ice front, and that only the depth-varying (baroclinic) component, which is typically much smaller, can enter the sub-ice cavity. Our results arise from direct observations of the Getz Ice Shelf system and laboratory experiments on a rotating platform. A similar blocking of the barotropic component may occur in other areas with comparable ice-bathymetry configurations, which may explain why changes in the density structure of the water column have been found to be a better indicator of basal melt rate variability than the heat transported onto the continental shelf9. Representing the step topography of the ice front accurately in models is thus important for simulating ocean heat fluxes and induced melt rates.

2.
J Am Chem Soc ; 144(11): 4839-4844, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35258969

RESUMEN

Recent studies have sparked debate over whether catalytic reactions enhance the diffusion coefficients D of enzymes. Through high statistics of the transient (600 µs) displacements of unhindered single molecules freely diffusing in common buffers, we here quantify D for four enzymes under catalytic turnovers. We thus formulate how ∼ ±1% precisions may be achieved for D, and show no changes in diffusivity for catalase, urease, aldolase, and alkaline phosphatase under the application of wide concentration ranges of substrates. Our single-molecule approach thus overcomes potential limitations and artifacts underscored by recent studies to show no enhanced diffusion in enzymatic reactions.


Asunto(s)
Fructosa-Bifosfato Aldolasa , Nanotecnología , Fosfatasa Alcalina , Difusión , Ureasa
3.
Aesthetic Plast Surg ; 46(2): 907-911, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34767060

RESUMEN

With the increase of cosmetic injectable hyaluronic acid (HA), there have been more cases with serious complications, including skin necrosis, blindness, and cerebral embolism. Patients who have recovered from HA filler-induced total vision loss are extremely rare. We report a case of a 27-year-old female who developed severe ocular pain on the right side and total vision loss following a 1.0 ml HA filler injection in the nasal dorsum. She arrived at our hospital 4 hours later. Her visual acuity was no light perception (NLP), and she exhibited eyelid ptosis, ophthalmoplegia, and frontal and nasal ecchymosis. She was promptly treated with subcutaneous and retrobulbar hyaluronidase injections, as well as intra-arterial 1500 IU hyaluronidase injections into the right ophthalmic artery with DSA assistance. Her vision improved from NLP to counting fingers at 1.0 meters. Unfortunately, 13 hours later, she felt an intense headache, and her vision again decreased to NLP. We immediately performed an injection of 1500 IU hyaluronidase combined with 8 mg alteplase for intra-arterial thrombolysis (IAT) into the right ophthalmic artery. Her vision improved immediately afterward. After 3 months, her visual acuity had significantly recovered from NLP (admission vision status) to 20/50 (Snellen chart with glasses). Similarly, skin, conjunctival, eye movement, and ptosis symptoms completely recovered. This case demonstrates that reversal of complete blindness due to embolism of the ophthalmic and central retinal arteries could be accomplished through multidisciplinary therapies, especially IAT using fibrinolytic agents combined with hyaluronidase followed by an anticoagulant regimen.Level of evidence VThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Técnicas Cosméticas , Rellenos Dérmicos , Adulto , Ceguera/etiología , Técnicas Cosméticas/efectos adversos , Femenino , Fibrinolíticos/efectos adversos , Humanos , Ácido Hialurónico/efectos adversos , Hialuronoglucosaminidasa , Inyecciones Intraarteriales
4.
Aesthetic Plast Surg ; 45(6): 2665-2675, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34251473

RESUMEN

INTRODUCTION: The most common surgical approaches for breast augmentation in Asia have traditionally been peri-areolar and transaxillary. In recent years, transaxillary approach has become increasingly popular with the use of endoscopic methods, which result in safer and better outcomes. In the literature, there are no comparison studies of endoscopic transaxillary and peri-areolar approaches. METHODS: This prospective study compared the outcomes of 275 women undergoing primary breast augmentation (endoscopic transaxillary n=205, peri-areolar n=70). All procedures were performed by a single surgeon using smooth round silicone implants and dual-plane pockets from April 2013 to March 2016. Every patient was monitored for a minimum of 4 years for minor and major complications. RESULTS: Types and percentage of patients experiencing minor complications among transaxillary and peri-areolar patients were localized fluid collection in the wound (1% transaxillary, 7.1% peri-areolar), hypertrophic scarring or keloids (1% transaxillary, 8.6% peri-areolar), and areolar and nipple deformity (0% transaxillary, 8.6% peri-areolar). Major complications were postoperative bleeding (0% transaxillary, 2.9% peri-areolar) and capsular contracture, Baker Group III or IV (1% transaxillary, 5.7% peri-areolar). CONCLUSIONS: Endoscopic transaxillary breast augmentation had better outcomes, with lower rates of complications than the peri-areolar approach. Reviewing the literature, our study is the first direct comparison of peri-areolar and endoscopic transaxillary incisions using smooth implants. With the risk of anaplastic large cell lymphoma associated with certain macrotexture implants, endoscopic transaxillary approach using smooth implants is the safer technique and very good alternative choice for Asian women who do not want any scarring on their breasts. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Asunto(s)
Implantación de Mama , Implantes de Mama , Mamoplastia , Implantación de Mama/efectos adversos , Implantes de Mama/efectos adversos , Estética , Femenino , Humanos , Pezones/cirugía , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
5.
Angiol Sosud Khir ; 27(1): 24-32, 2021.
Artículo en Ruso | MEDLINE | ID: mdl-33825725

RESUMEN

AIM: The study was aimed at comparing efficacy of conventional conservative therapy and comprehensive treatment including a plasmid VEGF-165-gene therapy drug in 'no-option' chronic limb-threatening ischaemia with different prevalence of trophic ulcers and infection during a 1-year follow-up period. PATIENTS AND METHODS: A total of 101 patients (54% being men and 46% women, mean age 69 years) with 'no-option' chronic limb-threatening ischaemia underwent comprehensive conservative treatment. They were subdivided into 4 groups according to the WIFI classification: WIFI 130 (n=38), 131 (n=23), 230 (n=16), 231 (n=24). The control group patients (n=58) received standard treatment using a PGE1 analogue (Vasaprostan) and the study group patients (n=43) underwent standard conservative treatment (SCT) in combination with gene therapy. The end points of the study were as follows: major amputation rate, amputation-free survival, total mortality, and ulcer healing rate during a 1-year of follow up. RESULTS: Major amputation rate in the control and study groups amounted to 35 and 28% (p=0.48), respectively, with amputation-free survival of 53 and 63% (p=0.35), total mortality of 21 and 12% (p=0.23), ulcer healing rate of 31 and 51% (p=0.04), respectively. The WIfI classification made it possible to single out a subgroup of patients (WIfI combination 130) yielding other statistically significant results: major amputation rate 27% and 0% (p=0.03), amputation-free survival 59 and 94% (p=0.025), ulcer healing rate 50 and 88% (p=0.016), respectively. CONCLUSION: Using plasmid-based VEGF-165 gene therapy in the subgroup with the WIfI combination 130 decreases the major amputation rate (p=0.03), increases amputation-free survival (p=0.025) and promotes ulcer healing (p=0.016) compared with the standard therapy during 1-year follow up. No significant differences in the compared groups were revealed by all endpoints of the study for other combinations analysed. The total mortality rate in patients with limb-threatening ischaemia does not depend on either the initial severity of ulcer or the selcted methods of conservative treatment.


Asunto(s)
Tratamiento Conservador , Recuperación del Miembro , Anciano , Amputación Quirúrgica , Femenino , Humanos , Isquemia/cirugía , Estimación de Kaplan-Meier , Masculino , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Cicatrización de Heridas
6.
Acc Chem Res ; 52(10): 2793-2805, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31553568

RESUMEN

Plasmonic nanoparticles are widely exploited in diverse bioapplications ranging from therapeutics to biosensing and biocomputing because of their strong and tunable light-matter interactions, facile and versatile chemical/biological ligand modifications, and biocompatibility. With the rapid growth of nanobiotechnology, understanding dynamic interactions between nanoparticles and biological systems at the molecular or single-particle level is becoming increasingly important for interrogating biological systems with functional nanostructures and for developing nanoparticle-based biosensors and therapeutic agents. Therefore, significant efforts have been devoted to precisely design and create nano-bio interfaces by manipulating the nanoparticles' size, shape, and surface ligand interactions with complex biological systems to maximize their performance and avoid unwanted responses, such as their agglomeration and cytotoxicity. However, investigating physicochemical interactions at the nano-bio interfaces in a quantitative and controllable manner remains challenging, as the interfaces involve highly complex networks between nanoparticles, biomolecules, and cells across multiple scales, each with a myriad of different chemical and biological interactions. A lipid bilayer is a membrane made of two layers of lipid molecules that forms a barrier around cells and plays structural and functional roles in diverse biological processes because they incorporate and present functional molecules (such as membrane proteins) with lateral fluidity. Plasmonic nanoparticles conjugated on lipid membranes provide reliable analytical labels and functional moieties that allow for studying and manipulating interactions between nanoparticles and molecules with single-particle resolution; they also serve as efficient tools for applying optical, mechanical, and thermal stimuli to biological systems, which stem from plasmonic properties. Recently, new opportunities have emerged by interfacing nanoparticle-modified lipid bilayers (NLBs) with complex systems such as molecular circuits and living systems. In this Account, we briefly review how plasmonic properties can be beneficially harnessed on lipid bilayer membranes to investigate the structures and functions of cellular membranes and to develop new platforms for biomedical applications. In particular, we discuss the versatility of supported lipid bilayers (SLBs), which are planar lipid bilayers on hydrophilic substrates, as dynamic biomaterials that provide lateral fluidity and cell membrane-like environments. We then summarize our efforts to create a quantitative analytical platform utilizing nanoparticles as active building blocks and SLBs as integrative substrates. Through this bottom-up approach, various functionalized nanoparticles have been introduced onto lipid bilayers to render nanoparticle-nanoparticle, nanoparticle-lipid bilayer, and biomolecule-lipid bilayer interfaces programmable. Our system provides a new class of tools for studying thermodynamics and kinetics in complex networks of nanostructures and for realizing unique applications in biosensing and biocomputing.


Asunto(s)
Membrana Celular , Membrana Dobles de Lípidos , Nanopartículas , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo
7.
N Z Vet J ; 68(5): 309-312, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32422083

RESUMEN

Aims: To compare detection by real-time PCR of DNA from Mycoplasma bovis on mucosal swabs taken from the palatine tonsillar crypt and the mainstem bronchi of clinically asymptomatic calves after slaughter. Methods: We compared the sensitivity of mucosal swabs taken from two sites: the palatine tonsillar crypt and the mainstem bronchi. Paired samples were taken post-mortem at slaughter from 55 clinically well calves from an infected herd and were tested by real-time PCR for the presence of M. bovis-specific DNA. Results: Mycoplasma bovis DNA was detected in 51 palatine tonsillar crypt swabs (92.7 (95% CI = 82.4-98.0)%) and seven mainstem bronchial swabs (12.7 (95% CI = 5.3-24.5)%). All seven calves with positive mainstem bronchial swabs also had positive palatine tonsillar crypt swabs. Conclusions: When compared to mucosal swabs of the mainstem bronchi, mucosal swabs of the palatine tonsillar crypt were seven times more sensitive for the post-mortem detection of M. bovis DNA. The viability of detected M. bovis was not assessed, because any cattle carrying viable or non-viable M. bovis DNA were determined to be a potential risk to eradication. Palatine tonsillar crypt mucosa may be a useful anatomical site for real-time PCR detection of M. bovis DNA in naturally infected calves. More work is needed to define the persistence and viability of M. bovis at this anatomical site. Clinical relevance: The results of this study helped form the basis of surveillance tools used in M. bovis control and eradication efforts. Familiarity with these results may help veterinarians better communicate with their clients about the science behind the eradication efforts.


Asunto(s)
Bronquios/microbiología , Enfermedades de los Bovinos/diagnóstico , Infecciones por Mycoplasma/veterinaria , Mycoplasma bovis/aislamiento & purificación , Tonsila Palatina/microbiología , Animales , Bovinos , Membrana Mucosa , Infecciones por Mycoplasma/diagnóstico , Sensibilidad y Especificidad
8.
Small ; 15(26): e1900998, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31026121

RESUMEN

Biocomputation is the algorithmic manipulation of biomolecules. Nanostructures, most notably DNA nanostructures and nanoparticles, become active substrates for biocomputation when modified with stimuli-responsive, programmable biomolecular ligands. This approach-biocomputing with nanostructures ("nano-bio computing")-allows autonomous control of matter and information at the nanoscale; their dynamic assemblies and beneficial properties can be directed without human intervention. Recently, lipid bilayers interfaced with nanostructures have emerged as a new biocomputing platform. This new nano-bio interface, which exploits lipid bilayers as a chemical circuit board for information processing, offers a unique reaction space for realizing nanostructure-based computation at a previously unexplored dimension. In this Concept, recent advances in nano-bio computing are briefly reviewed and the newly emerging concept of biocomputing with nanostructures on lipid bilayers is introduced.


Asunto(s)
ADN/química , Membrana Dobles de Lípidos/química , Nanoestructuras/química , Nanopartículas/química , Nanotecnología/métodos
9.
Proc Natl Acad Sci U S A ; 113(8): 2098-103, 2016 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-26858402

RESUMEN

We investigate the folding of GlpG, an intramembrane protease, using perfectly funneled structure-based models that implicitly account for the absence or presence of the membrane. These two models are used to describe, respectively, folding in detergent micelles and folding within a bilayer, which effectively constrains GlpG's topology in unfolded and partially folded states. Structural free-energy landscape analysis shows that although the presence of multiple folding pathways is an intrinsic property of GlpG's modular functional architecture, the large entropic cost of organizing helical bundles in the absence of the constraining bilayer leads to pathways that backtrack (i.e., local unfolding of previously folded substructures is required when moving from the unfolded to the folded state along the minimum free-energy pathway). This backtracking explains the experimental observation of thermodynamically destabilizing mutations that accelerate GlpG's folding in detergent micelles. In contrast, backtracking is absent from the model when folding is constrained within a bilayer, the environment in which GlpG has evolved to fold. We also characterize a near-native state with a highly mobile transmembrane helix 5 (TM5) that is significantly populated under folding conditions when GlpG is embedded in a bilayer. Unbinding of TM5 from the rest of the structure exposes GlpG's active site, consistent with studies of the catalytic mechanism of GlpG that suggest that TM5 serves as a substrate gate to the active site.


Asunto(s)
Proteínas de Unión al ADN/química , Endopeptidasas/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimología , Membrana Dobles de Lípidos/química , Proteínas de la Membrana/química , Modelos Moleculares , Pliegue de Proteína
10.
Sensors (Basel) ; 19(18)2019 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-31546772

RESUMEN

This paper presents two methods to optimize LoRa (Low-Power Long-Range) devices so that implementing multiplier-less pulse shaping filters is more economical. Basic chirp waveforms can be generated more efficiently using the method of chirp segmentation so that only a quarter of the samples needs to be stored in the ROM. Quantization can also be applied to the basic chirp samples in order to reduce the number of unique input values to the filter, which in turn reduces the size of the lookup table for multiplier-less filter implementation. Various tests were performed on a simulated LoRa system in order to evaluate the impact of the quantization error on the system performance. By examining the occupied bandwidth, fast Fourier transform used for symbol demodulation, and bit-error rates, it is shown that even performing a high level of quantization does not cause significant performance degradation. Therefore, the memory requirements of LoRa devices can be significantly reduced by using the methods of chirp segmentation and quantization so as to improve the feasibility of implementing multiplier-less filters in LoRa devices.

11.
Artículo en Inglés | MEDLINE | ID: mdl-30633631

RESUMEN

CuO-CeO2 catalysts supported on material synthesized from red mud and rice husk ash (CuO-CeO2/ZRM) were prepared by co-impregnation method. The role of CeO2 additive in the improvement of physicochemical properties and catalytic activity of CuO-CeO2/ZRM catalysts were emphasized. Several techniques, including Brunauer-Emmett-Teller Nitrogen physisorption measurements, X-ray powder diffraction, hydrogen temperature programed reduction, scanning electron microscopy and transmission electron microscopy (TEM) were used to investigate the properties of catalysts. Crystallite size calculated by Scherrer' equation was 17.4 - 21.8 nm. Modification of 5 wt% CuO/ZRM catalyst with CeO2 had reduced the size of the nanoparticles leading to a significant enhancement of the catalytic activity in p-xylene deep oxidation at temperature range of 275 - 400 °C. The 5 wt% CuO/ZRM sample promoted by 3 wt% of nanoparticle CeO2 with the average size of 17.5 nm and BET surface area of 31.3 m2 g-1 exhibited the best activity for p-xylene deep oxidation. In this sample, the conversion of p-xylene reaches to 90% at 350 °C.


Asunto(s)
Cerio/química , Cobre/química , Nanopartículas/química , Oryza/química , Xilenos/análisis , Zeolitas/química , Catálisis , Oxidación-Reducción , Tamaño de la Partícula , Tallos de la Planta/química , Propiedades de Superficie , Temperatura
12.
J Aquat Anim Health ; 31(4): 311-319, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31344755

RESUMEN

Acute hepatopancreatic necrosis disease (AHPND) is a new emerging bacterial disease that has been recently reported to cause mass mortalities in Pacific whiteleg shrimp Penaeus vannamei. Antibiotics have been used to treat bacterial diseases in shrimp, but most of them have been ineffective and have resulted in drug residues in the harvested shrimp products. In this study, an alternative approach was tested for its efficacy in controlling AHPND. The extract of rose myrtle Rhodomyrtus tomentosa seed, a traditional Vietnamese medicine, was tested for antibacterial effect against three AHPND bacterial strains in vitro (Vibrio parahaemolyticus [VPAHPND ] KC12.020, VPAHPND KC13.14.2, and V. harveyi KC13.17.5) and was further evaluated for its potential efficacy in prevention of AHPND in shrimp in vivo. The in vitro studies showed that the antibacterial activity of the R. tomentosa extract was dose dependent, with the strongest bacterial susceptibility (≥18.0 mm) at a concentration of around 3,500 µg/disc. The in vivo studies showed that after challenge with VPAHPND KC12.020, the survival rates for shrimp in the groups that received feed pellets supplemented with extract at 3.5% or 7.0% (survival ~48.9% and 52.2%, respectively) were significantly higher than the zero survival rate in the positive control group, which received feed without the extract. These results indicate that the use of the R. tomentosa extract as an alternative therapy for control of AHPND in shrimp could help to minimize disease outbreaks. As a result, the extract is further expected to reduce drug/chemical residues in shrimp products.


Asunto(s)
Antibacterianos/farmacología , Myrtaceae/química , Penaeidae/microbiología , Extractos Vegetales/farmacología , Vibrio parahaemolyticus/efectos de los fármacos , Animales , Hepatopáncreas/patología , Necrosis/patología , Extractos Vegetales/química , Semillas/química
13.
J Fish Dis ; 2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29806079

RESUMEN

A rickettsia-like organism, designated NZ-RLO2, was isolated from Chinook salmon (Oncorhynchus tshawytscha) farmed in the South Island, New Zealand. In vivo growth showed NZ-RLO2 was able to grow in CHSE-214, EPC, BHK-21, C6/36 and Sf21 cell lines, while Piscirickettsia salmonis LF-89T grew in all but BHK-21 and Sf21. NZ-RLO2 grew optimally in EPC at 15°C, CHSE-214 and EPC at 18°C. The growth of LF-89 T was optimal at 15°C, 18°C and 22°C in CHSE-24, but appeared less efficient in EPC cells at all temperatures. Pan-genome comparison of predicted proteomes shows that available Chilean strains of P. salmonis grouped into two clusters (p-value = 94%). NZ-RLO2 was genetically different from previously described NZ-RLO1, and both strains grouped separately from the Chilean strains in one of the two clusters (p-value = 88%), but were closely related to each other. TaqMan and Sybr Green real-time PCR targeting RNA polymerase (rpoB) and DNA primase (dnaG), respectively, were developed to detect NZ-RLO2. This study indicates that the New Zealand strains showed a closer genetic relationship to one of the Chilean P. salmonis clusters; however, more Piscirickettsia genomes from wider geographical regions and diverse hosts are needed to better understand the classification within this genus.

15.
Osteoporos Int ; 28(4): 1453-1459, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28083665

RESUMEN

Because the rate of bone loss is an important risk factor for fracture, we studied longitudinal changes in bone mineral density (BMD). Although the BMD of the hip decreased over time, spine BMD remained largely stable or increased. Therefore, spine BMD may not be appropriate for assessing BMD change. INTRODUCTION: The rate of age-dependent bone loss has been shown to be an important risk factor for fracture. However, longitudinal rates of BMD loss in Korea have not yet been reported. The objective of this study was to evaluate longitudinal changes in BMD in Korea. METHODS: This cohort study was performed in a population of individuals 40 years of age or older living in the rural area of Chungju City, Korea. A second BMD examination was conducted approximately 4 years after a baseline examination. A total of 3755 of the 6007 subjects completed the follow-up visit, corresponding to a follow-up rate of 62.51%. RESULTS: The age-standardized osteoporosis prevalence was 12.81% in males and 44.35% in females. In males, the average annual BMD loss at the total hip increased from -0.25% per year in their 40s to -1.12% per year in their 80s. In females, the average annual BMD loss at the total hip increased from -0.69% per year in their 40s to -1.51% per year in their 80s. However, the average annual percentage change in spine BMD in females increased from -0.91% per year in their 40s to +1.39% per year in their 80s. CONCLUSIONS: A substantial number of subjects had osteoporosis, even though we standardized the prevalence of osteoporosis. In total hip, the mean BMD was decreased during the follow-up period; in addition, the annual percentage loss increased with age. However, spine BMD remained approximately stable or increased over time and therefore may not be appropriate for assessing BMD change.


Asunto(s)
Densidad Ósea/fisiología , Osteoporosis/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Enfermedades Óseas Metabólicas/epidemiología , Enfermedades Óseas Metabólicas/fisiopatología , Estudios de Cohortes , Femenino , Cuello Femoral/fisiopatología , Articulación de la Cadera/fisiopatología , Humanos , Estudios Longitudinales , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología , Prevalencia , República de Corea/epidemiología , Salud Rural/estadística & datos numéricos
16.
Br J Nutr ; 118(12): 1031-1042, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29202889

RESUMEN

A foundation diet, an intermediate blend and a summit diet were formulated with different levels of soyabean meal, casein and crystalline amino acids to compare 'slow' and 'rapid' protein diets. The diets were offered to male Ross 308 chicks from 7 to 28 d post-hatch and assessed parameters included growth performance, nutrient utilisation, apparent digestibility coefficients and disappearance rates of starch and protein (N) in four small intestinal segments. Digestibility coefficients and disappearance rates of sixteen amino acids in three small intestinal segments and amino acid concentrations in plasma from portal and systemic circulations from the foundation and summit diets were determined. The dietary transition significantly accelerated protein (N) disappearance rates in the distal jejunum and ileum. The transition from foundation to summit diets significantly increased starch digestibility coefficients in the ileum and disappearance rates in all four small intestinal segments. These starch responses were associated with significant enhancements in nutrient utilisation. The dietary transition linearly increased digestibility coefficients and disappearance rates of amino acids in the majority of cases. The summit diet increased plasma concentrations of five amino acids but decreased those of four amino acids relative to the foundation diet to significant extents. Plasma concentrations of free amino acids were higher in the portal than systemic circulations. Rapid protein disappearance rates advantaged poultry performance and influenced post-enteral availability of amino acids. If the underlying mechanisms are to be identified, further research into the impact of protein digestive dynamics on broiler performance is required but appears justified.


Asunto(s)
Aminoácidos/administración & dosificación , Aminoácidos/sangre , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Intestino Delgado/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Caseínas/administración & dosificación , Caseínas/metabolismo , Pollos/crecimiento & desarrollo , Proteínas en la Dieta/metabolismo , Digestión , Masculino , Aves de Corral , Glycine max/química , Almidón/administración & dosificación , Almidón/metabolismo
17.
Molecules ; 22(12)2017 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-29207465

RESUMEN

Measurement of telomere length by fluorescent in situ hybridization is widely used for biomedical and epidemiological research, but there has been relatively little development of the technology in the 20 years since it was first reported. This report describes the use of dual gammaPNA (γPNA) probes that hybridize at alternating sites along a telomere and give rise to Förster resonance energy transfer (FRET) signals. Bright staining of telomeres is observed in nuclei, chromosome spreads and tissue samples. The use of FRET detection also allows for elimination of wash steps, normally required to remove unhybridized probes that would contribute to background signals. We found that these wash steps can diminish the signal intensity through the removal of bound, as well as unbound probes, so eliminating these steps not only accelerates the process but also enhances the quality of staining. Thus, γPNA FRET pairs allow for brighter and faster staining of telomeres in a wide range of research and clinical formats.


Asunto(s)
ADN/metabolismo , Transferencia Resonante de Energía de Fluorescencia/métodos , Hibridación Fluorescente in Situ/métodos , Telómero/metabolismo , Secuencia de Bases , Recuento de Células , Línea Celular , Colorantes Fluorescentes/química , Humanos , Estructura Molecular , Hibridación de Ácido Nucleico , Imagen Óptica/métodos , Osteosarcoma , Ácidos Nucleicos de Péptidos/metabolismo
18.
N Z Vet J ; 65(4): 214-218, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28372487

RESUMEN

CASE HISTORY: An investigation was conducted to identify the cause of mortalities in freshwater reared Chinook salmon (Oncorhynchus tshawytscha). Mortalities occurred in juvenile salmon, at a salmon rearing facility in the South Island of New Zealand. The affected fish were from a pen inside the facility with no surrounding pens or other year classes affected. CLINICAL FINDINGS: Clinically affected fish presented with skin lesions. The majority of skin lesions were unruptured, boil-like, raised circular masses up to 4 cm in diameter, particularly on the dorsolateral aspects and the flank. A number of fish presented with large ulcers resulting from rupturing of the raised lesions described above. This clinical presentation showed similarities to that of furunculosis caused by typical Aeromonas salmonicida, a bacterium exotic to New Zealand. LABORATORY FINDINGS: Samples were taken from two representative fish in the field for histopathology, bacterial culture and molecular testing. Histopathological findings included granulomatous lesions in the kidney, liver, spleen and muscle. When stained with Fite-Faraco modified acid fast stain filamentous branching rods were identified within these granulomas. Following bacterial culture of kidney swabs pure growth of small white matt adherent colonies was observed. This isolate was identified as a Nocardia species by biochemical testing and nucleotide sequencing of the partial 16S rRNA gene. All samples were negative for A. salmonicida based on bacterial culture and PCR testing. DIAGNOSIS: Nocardiosis caused by a Nocardia species. CLINICAL RELEVANCE: Nocardiosis in these fish was caused by a previously undescribed Nocardia species that differs from the species known to be pathogenic to fish: N. asteroides, N. salmonicida and N. seriole. This bacterium is likely to be a new or unnamed environmental species of Nocardia that has the potential to cause disease in Chinook salmon under certain conditions. The clinical presentation of this Nocardia species manifested as raised, boil-like skin lesions which has similarities to the presentation of furunculosis caused by the bacterium typical A. salmonicida, a species exotic to New Zealand.


Asunto(s)
Enfermedades de los Peces/microbiología , Nocardiosis/veterinaria , Nocardia/aislamiento & purificación , Salmón/microbiología , Animales , Bases de Datos de Ácidos Nucleicos , Enfermedades de los Peces/genética , Enfermedades de los Peces/patología , Agua Dulce , Genes de ARNr , Nueva Zelanda , Nocardia/genética , Nocardiosis/genética , Nocardiosis/patología , Reacción en Cadena de la Polimerasa
19.
Br Poult Sci ; 58(6): 718-728, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28841035

RESUMEN

1. The objective of this study was to compare the effects of pre- and post-pellet whole grain wheat additions to diets on growth performance, gizzard and pancreas development, nutrient utilisation and starch and protein (N) digestibility coefficients in broiler chickens via an equilateral triangle response surface design. 2. The three apical treatments of the equilateral triangle comprised (1A) a standard diet containing 600 g/kg ground wheat, (2B) the same diet containing 600 g/kg pre-pellet whole wheat and (3C) the same diet containing 300 g/kg ground wheat and 300 g/kg post-pellet whole wheat. Seven blends of the three apical diets were located within the triangle to complete the design and a total of 360 male Ross 308 chicks were offered the ten experimental diets from 7 to 28 d post-hatch. Model prediction and response surface plots were generated with R 3.0.3 software. 3. The most efficient FCR of 1.466 was observed in birds offered an almost equal mixture of the pre- and post-pellet whole grain apical dietary treatments, which corresponded to 172 g/kg ground grain, 256 g/kg pre-pellet whole grain, 172 g/kg post-pellet whole grain in a diet containing 600 g/kg wheat. 4. The most efficient energy utilisation (ME:GE ratio of 0.766) was observed in birds offered a blend of the ground grain and pre-pellet whole grain apical dietary treatments which corresponded to a mixture of 384 g/kg pre-pellet whole grain and 216 g/kg ground grain. 5. Pre-pellet whole grain feeding generated the most pronounced responses in increased relative gizzard contents, reduced gizzard pH and increased relative pancreas weights. Consideration is given to the likely differences between pre- and post-pellet whole grain feeding.


Asunto(s)
Alimentación Animal/análisis , Pollos/fisiología , Digestión/efectos de los fármacos , Triticum/química , Granos Enteros/química , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Proteínas en la Dieta , Digestión/fisiología , Molleja de las Aves/efectos de los fármacos , Molleja de las Aves/crecimiento & desarrollo , Masculino , Páncreas/efectos de los fármacos , Páncreas/crecimiento & desarrollo , Almidón/fisiología
20.
Diabet Med ; 33(5): 631-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26220259

RESUMEN

AIM: To determine whether preadipocyte factor 1 could be a predictive marker for the development of diabetes in people without diabetes at baseline. METHODS: We conducted a population-based, nested case-control study of individuals who progressed to diabetes (n = 43) or prediabetes (n = 345) and control participants matched on age, sex and fasting plasma glucose concentration, who maintained normal glucose tolerance (n = 389) during a 4-year follow-up using data from the Chungju Metabolic disease Cohort Study. Circulating levels of preadipocyte factor 1 were measured using an enzyme-linked immunosorbent assay. RESULTS: Baseline serum preadipocyte factor 1 levels showed a stepwise decrease across the glucose tolerance status groups at follow-up (normal glucose tolerance: 10.02 ± 3.02 ng/ml; prediabetes: 9.48 ± 3.35 ng/ml; diabetes: 8.66 ± 3.29 ng/ml; P for trend, 0.0151). Individuals whose fasting plasma glucose level had increased or whose homeostasis model assessment of ß-cell function had decreased at follow-up showed significantly lower levels of preadipocyte factor 1 compared with their control group counterparts. After adjusting for age, BMI, fasting plasma glucose, serum insulin levels, systolic blood pressure and triglycerides, the incidence of diabetes was nearly threefold higher in the lowest vs. the upper three quartiles of circulating preadipocyte factor 1 (relative risk 2.794; 95% CI 1.188-6.571; P = 0.0185). Notably, these findings were significant in women but not in men. CONCLUSIONS: Levels of circulating preadipocyte factor 1 may be a useful biomarker for identifying women at high risk of developing diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Regulación hacia Abajo , Resistencia a la Insulina , Péptidos y Proteínas de Señalización Intercelular/sangre , Proteínas de la Membrana/sangre , Estado Prediabético/epidemiología , Salud Rural , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Glucemia/análisis , Proteínas de Unión al Calcio , Estudios de Casos y Controles , Estudios de Cohortes , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Estado Prediabético/metabolismo , República de Corea/epidemiología , Riesgo , Factores Sexuales
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