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2.
Animal ; 16(3): 100462, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35180682

RESUMO

High levels of supplementation with cereal increases production rates in cattle but can increase incidence of disease, ranging from mild indigestion to acute ruminal acidosis and death. Therefore, there is motivation to determine biological markers which can be used to identify whether animals have been, or are being fed, sufficient or excessive cereals. This study aimed to describe light microscopic findings from animals being fed diverse dietary cereal proportions and to test the performance of a novel rumen epithelial scoring system. Rumen wall tissue samples were obtained from the abattoir from 195 cattle from 11 Scottish farms and processed for histological examination. Light microscopic examination was used to characterise ruminal epithelial response to dietary challenge. Secondary objectives included describing the distribution of immune-related cells in bovine ruminal epithelium and assessing the use of a modified Elastin Martius Scarlet Blue stain (EMSB) for histological examination of the rumen epithelium. Cells staining positive for cluster of differentiation 3 were distributed mainly in the lower layers of the stratum basale and were found in higher densities in animals offered lower cereal proportion diets. Cells staining positive for major histocompatibility complex class 2 (MHCII) were most common in perivascular locations and in the junction between the lower stratum basale and the propria-submucosa. The density of MHCII positive staining cells was higher in animals on lower cereal diets. The level of supplementation with cereal was also associated with the thickness of the stratum corneum (SCT) and stratum granulosum (SGT), the integrity of the stratum corneum and sloughing of cornified cells. There were no advantages in using EMSB stain over haematoxylin and eosin (H&E) in this scoring system. We concluded that a scoring system that included only SCT, SGT and a measure of the loss of appearance of intercellular space allowed differentiation of groups of animals according to the level of cereal supplementation.


Assuntos
Acidose , Doenças dos Bovinos , Acidose/veterinária , Ração Animal/análise , Animais , Bovinos , Doenças dos Bovinos/etiologia , Dieta/veterinária , Grão Comestível , Epitélio , Concentração de Íons de Hidrogênio , Rúmen/fisiologia
3.
Zootaxa ; 4819(1): zootaxa.4819.1.11, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055678

RESUMO

Betta nuluhon, new species, is described from a hill stream habitat in western Sabah. This species is allied to both B. chini and B. balunga, and differs from rest of its congeners in the B. akarensis group in having the following combination of characters: yellow iris when live; mature males with greenish-blue iridescence on opercle when live; mature fish with distinct transverse bars on caudal fin; slender body (body depth 22.1-25.2 % SL); belly area with faint reticulate pattern (scales posteriorly rimmed with black); absence of tiny black spots on anal fin; lateral scales 29-31 (mode 30); predorsal scales 20-21 (mode 20). Notes on a fresh series of B. chini are also provided.


Assuntos
Peixes , Animais , Cor , Ecossistema , Malásia , Masculino , Rios
4.
Animal ; 14(7): 1447-1460, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31875798

RESUMO

Sub-acute ruminal acidosis (SARA) can reduce the production efficiency and impair the welfare of cattle, potentially in all production systems. The aim of this study was to characterise measurable postmortem observations from divergently managed intensive beef finishing farms with high rates of concentrate feeding. At the time of slaughter, we obtained samples from 19 to 20 animals on each of 6 beef finishing units (119 animals in total) with diverse feeding practices, which had been subjectively classified as being high risk (three farms) or low risk (three farms) for SARA on the basis of the proportions of barley, silage and straw in the ration. We measured the concentrations of histamine, lipopolysaccharide (LPS), lactate and other short-chain fatty acids (SCFAs) in ruminal fluid, LPS and SCFA in caecal fluid. We also took samples of the ventral blind sac of the rumen for histopathology, immunohistopathology and gene expression. Subjective assessments were made of the presence of lesions on the ruminal wall, the colour of the lining of the ruminal wall and the shape of the ruminal papillae. Almost all variables differed significantly and substantially among farms. Very few pathological changes were detected in any of the rumens examined. The animals on the high-risk diets had lower concentrations of SCFA and higher concentrations of lactate and LPS in the ruminal fluid. Higher LPS concentrations were found in the caecum than the rumen but were not related to the risk status of the farm. The diameters of the stratum granulosum, stratum corneum and of the vasculature of the papillae, and the expression of the gene TLR4 in the ruminal epithelium were all increased on the high-risk farms. The expression of IFN-γ and IL-1ß and the counts of cluster of differentiation 3 positive and major histocompatibility complex class two positive cells were lower on the high-risk farms. High among-farm variation and the unbalanced design inherent in this type of study in the field prevented confident assignment of variation in the dependent variables to individual dietary components; however, the CP percentage of the total mixed ration DM was the factor that was most consistently associated with the variables of interest. Despite the strong effect of farm on the measured variables, there was wide inter-animal variation.


Assuntos
Hordeum , Rúmen , Ração Animal/análise , Animais , Bovinos , Ceco , Dieta/veterinária , Fermentação , Expressão Gênica , Hordeum/genética , Concentração de Íons de Hidrogênio , Rúmen/metabolismo , Silagem/análise
5.
Nano Lett ; 19(7): 4666-4677, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241966

RESUMO

We report a method for growing rectangular InAs nanofins with deterministic length, width, and height by dielectric-templated selective-area epitaxy. These freestanding nanofins can be transferred to lay flat on a separate substrate for device fabrication. A key goal was to regain a spatial dimension for device design compared to nanowires, while retaining the benefits of bottom-up epitaxial growth. The transferred nanofins were made into devices featuring multiple contacts for Hall effect and four-terminal resistance studies, as well as a global back-gate and nanoscale local top-gates for density control. Hall studies give a 3D electron density 2.5-5 × 1017 cm-3, corresponding to an approximate surface accumulation layer density 3-6 × 1012 cm-2 that agrees well with previous studies of InAs nanowires. We obtain Hall mobilities as high as 1200 cm2/(V s), field-effect mobilities as high as 4400 cm2/(V s), and clear quantum interference structure at temperatures as high as 20 K. Our devices show excellent prospects for fabrication into more complicated devices featuring multiple ohmic contacts, local gates, and possibly other functional elements, for example, patterned superconductor contacts, that may make them attractive options for future quantum information applications.

6.
J Hypertens ; 37(5): 985-996, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30308595

RESUMO

BACKGROUND: Combined congenic breeding and microarray gene expression profiling previously identified glutathione S-transferase µ-type 1 (Gstm1) as a positional and functional candidate gene for blood pressure (BP) regulation in the stroke-prone spontaneously hypertensive (SHRSP) rat. Renal Gstm1 expression in SHRSP rats is significantly reduced when compared with normotensive Wistar Kyoto (WKY) rats. As Gstm1 plays an important role in the secondary defence against oxidative stress, significantly lower expression levels may be functionally relevant in the development of hypertension. The aim of this study was to investigate the role of Gstm1 in BP regulation and oxidative stress by transgenic overexpression of the Gstm1 gene. METHOD: Two independent Gstm1 transgenic SHRSP lines were generated by microinjecting SHRSP embryos with a linear construct controlled by the EF-1α promoter encoding WKY Gstm1 cDNA [SHRSP-Tg(Gstm1)1 and SHRSP-Tg(Gstm1)2]. RESULTS: Transgenic rats exhibit significantly reduced BP and pulse pressure when compared with SHRSP [systolic: SHRSP 205.2 ±â€Š3.7 mmHg vs. SHRSP-Tg(Gstm1)1 175.5 ±â€Š1.6 mmHg and SHRSP-Tg(Gstm1)2 172 ±â€Š3.2 mmHg, P < 0.001; pulse pressure: SHRSP 58.4 ±â€Š0.73 mmHg vs. SHRSP-Tg(Gstm1)1 52.7 ±â€Š0.19 mmHg and SHRSP-Tg(Gstm1)2 40.7 ±â€Š0.53 mmHg, P < 0.001]. Total renal and aortic Gstm1 expression in transgenic animals was significantly increased compared with SHRSP [renal relative quantification (RQ): SHRSP-Tg(Gstm1)1 1.95 vs. SHRSP 1.0, P < 0.01; aorta RQ: SHRSP-Tg(Gstm1)1 2.8 vs. SHRSP 1.0, P < 0.05]. Renal lipid peroxidation (malondialdehyde: protein) and oxidized : reduced glutathione ratio levels were significantly reduced in both transgenic lines when compared with SHRSP [malondialdehyde: SHRSP 0.04 ±â€Š0.009 µmol/l vs. SHRSP-Tg(Gstm1)1 0.024 ±â€Š0.002 µmol/l and SHRSP-Tg(Gstm1)2 0.021 ±â€Š0.002 µmol/l; (oxidized : reduced glutathione ratio): SHRSP 5.19 ±â€Š2.26 µmol/l vs. SHRSP-Tg(Gstm1)1 0.17 ±â€Š0.11 µmol/l and SHRSP-Tg(Gstm1)2 0.47 ±â€Š0.22 µmol/l]. Transgenic SHRSP rats containing the WKY Gstm1 gene demonstrate significantly lower BP, reduced oxidative stress and improved levels of renal Gstm1 expression. CONCLUSION: These data support the hypothesis that reduced renal Gstm1 plays a role in the development of hypertension.


Assuntos
Pressão Sanguínea/genética , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Hipertensão/genética , Estresse Oxidativo/genética , Animais , Animais Geneticamente Modificados , Aorta/metabolismo , Glutationa/metabolismo , Hipertensão/fisiopatologia , Rim/metabolismo , Peroxidação de Lipídeos , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Transgênicos , Sístole
7.
Hum Reprod ; 33(11): 2141-2149, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30285230

RESUMO

STUDY QUESTION: Are higher overall and central adiposity associated with reduced fecundability, measured by time-to-pregnancy (TTP), in Asian women? SUMMARY ANSWER: Higher overall adiposity, but not central adiposity, was associated with longer TTP in Asian women. WHAT IS KNOWN ALREADY: High body mass index (BMI) has been associated with a longer TTP, although the associations of body composition and distribution with TTP are less clear. There are no previous studies of TTP in Asian women, who have a relatively higher percentage of body fat and abdominal fat at relatively lower BMI. STUDY DESIGN, SIZE, DURATION: Prospective preconception cohort using data from 477 Asian (Chinese, Malay and Indian) women who were planning to conceive and enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO) study, 2015-2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women's mean age was 30.7 years. Overall adiposity was assessed by BMI, sum of 4-site skinfold thicknesses (SFT) and total body fat percentage (TBF%, measured using air displacement plethysmography); central adiposity was assessed by waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and A body Shape Index (ABSI). Pregnancy occurring within one year from recruitment was ascertained by ultrasonography. Those who did not conceive within one year of recruitment, were lost to follow-up, or initiated fertility treatment were censored. TTP was measured in cycles. Discrete-time proportional hazards models were used to estimate the fecundability ratio (FR) and 95% confidence interval (CI) for each anthropometric measure in association with fecundability, adjusting for confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to women with a normal BMI of 18.5-22.9 kg/m2, women with higher BMI of 23-27.4 and ≥27.5 kg/m2 showed lower FR of 0.66 (95% CI 0.45, 0.97) and 0.53 (0.31, 0.89), respectively. Compared to women in the lowest quartile of SFT (25-52.9 mm), those in the highest quartile of ≥90.1 mm showed lower FR of 0.58 (95% CI 0.36, 0.95). Compared to women in the lowest quartile of TBF% (13.6-27.2%), those in the upper two quartiles of 33.0-39.7% and ≥39.8% showed lower FR of 0.56 (95% CI 0.32, 0.98) and 0.43 (0.24, 0.80), respectively. Association of high BMI with reduced fecundability was particularly evident among nulliparous women. Measures of central adiposity (WC, WHR, WHtR, ABSI) were not associated with fecundability. LIMITATIONS REASONS FOR CAUTION: Small sample size could restrict power of analysis.The analysis was confined to planned pregnancies, which could limit generalizability of findings to non-planned pregnancies, estimated at around 44% in Singapore. Information on the date of last menstrual period for each month was not available, hence the accuracy of self-reported menstrual cycle length could not be validated, potentially introducing error into TTP estimation. Measures of exposures and covariates such as cycle length were not performed repeatedly over time; cycle length might have changed during the period before getting pregnant. WIDER IMPLICATIONS OF THE FINDINGS: Other than using BMI as the surrogate measure of body fat, we provide additional evidence showing that higher amounts of subcutaneous fat that based on the measure of SFT at the sites of biceps, triceps, suprailiac and subscapular, and TBF% are associated with longer TTP. Achieving optimal weight and reducing total percentage body fat may be a potential intervention target to improve female fertility. The null results observed between central adiposity and TTP requires confirmation in further studies. STUDY FUNDING/COMPETING INTEREST(S): This research is supported by Singapore National Research Foundation under its Translational and Clinical Research Flagship Programme and administered by the Singapore Ministry of Health's National Medical Research Council, (NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014). Additional funding is provided by the Singapore Institute for Clinical Sciences, Agency for Science Technology and Research (A*STAR), Singapore. Y.S.C., K.M.G., F.Y. and Y.S.L. have received reimbursement to speak at conferences sponsored by companies selling nutritional products. Y.S.C., K.M.G. and S.Y.C. are part of an academic consortium that has received research funding from Abbott, Nutrition, Nestle and Danone. Other authors declared no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Adiposidade/fisiologia , Infertilidade Feminina/etiologia , Tempo para Engravidar , Adiposidade/etnologia , Adulto , Povo Asiático/estatística & dados numéricos , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Estimativa de Kaplan-Meier , Obesidade/complicações , Gravidez , Estudos Prospectivos , Singapura/epidemiologia
8.
Nanoscale ; 10(23): 11205-11210, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29873654

RESUMO

We report on the effect of nitridation on GaN self-assembled nanorods grown on the c-plane sapphire by metalorganic chemical vapour deposition (MOCVD). Nitridation conditions are found to critically influence the nanorod morphology and optical properties. The nanorod polarity was determined through a direct observation of atomic dumbbell pairs. While purely N-polar wires are obtained under optimised nitridation, incomplete or missing nitridation leads to mixed polarity. By comparing the morphology and the crystal structure with spatially resolved cathodoluminescence results, our study unambiguously establishes a link between appropriate nitridation duration and a homogeneous improvement in optical quality.

9.
Nanotechnology ; 28(45): 454001, 2017 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-29039362

RESUMO

We compare the characteristics of phase-pure MOCVD grown ZB and WZ InAs nanowire transistors in several atmospheres: air, dry pure N2 and O2, and N2 bubbled through liquid H2O and alcohols to identify whether phase-related structural/surface differences affect their response. Both WZ and ZB give poor gate characteristics in dry state. Adsorption of polar species reduces off-current by 2-3 orders of magnitude, increases on-off ratio and significantly reduces sub-threshold slope. The key difference is the greater sensitivity of WZ to low adsorbate level. We attribute this to facet structure and its influence on the separation between conduction electrons and surface adsorption sites. We highlight the important role adsorbed species play in nanowire device characterisation. WZ is commonly thought superior to ZB in InAs nanowire transistors. We show this is an artefact of the moderate humidity found in ambient laboratory conditions: WZ and ZB perform equally poorly in the dry gas limit yet equally well in the wet gas limit. We also highlight the vital role density-lowering disorder has in improving gate characteristics, be it stacking faults in mixed-phase WZ or surface adsorbates in pure-phase nanowires.

10.
Nanoscale ; 9(36): 13554-13562, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28872181

RESUMO

The usability and tunability of the essential InP-InGaAs material combination in nanowire-based quantum wells (QWs) are assessed. The wurtzite phase core-multi-shell InP-InGaAs-InP nanowire QWs are characterised using cross-section transmission electron microscopy and photoluminescence measurements. The InP-InGaAs direct interface is found to be sharp while the InGaAs-InP inverted interface is more diffused, in agreement with their planar counterpart. Bright emission is observed from the single nanowires containing the QWs at room temperature, with no emission from the InP core or outer barrier. The tunability of the QW emission wavelength in the 1.3-1.55 µm communication wavelength range is demonstrated by varying the QW thickness and in the 1.3 µm range by varying the composition. The experiments are supported by simulation of the emission wavelength of the wurtzite phase InP-InGaAs QWs in the thickness range considered. The radial heterostructure is further extended to design multiple QWs with bright emission, therefore establishing the capability of this material system for nanowire based optical devices for communication applications.

11.
J Hypertens ; 35(2): 319-329, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27755386

RESUMO

BACKGROUND: We have previously confirmed the importance of rat chromosome 3 (RNO3) genetic loci on blood pressure elevation, pulse pressure (PP) variability and renal pathology during salt challenge in the stroke-prone spontaneously hypertensive (SHRSP) rat. The aims of this study were to generate a panel of RNO3 congenic sub-strains to genetically dissect the implicated loci and identify positional candidate genes by microarray expression profiling and analysis of next-generation sequencing data. METHOD AND RESULTS: A panel of congenic sub-strains were generated containing Wistar-Kyoto (WKY)-introgressed segments of varying size on the SHRSP genetic background, focused within the first 50 Mbp of RNO3. Haemodynamic profiling during salt challenge demonstrated significantly reduced systolic blood pressure, diastolic blood pressure and PP variability in SP.WKYGla3a, SP.WKYGla3c, SP.WKYGla3d and SP.WKYGla3e sub-strains. Only SBP and DBP were significantly reduced during salt challenge in SP.WKYGla3b and SP.WKYGla3f sub-strains, whereas SP.WKYGla3g rats did not differ in haemodynamic response to SHRSP. Those sub-strains demonstrating significantly reduced PP variability during salt challenge also demonstrated significantly reduced renal pathology and proteinuria. Microarray expression profiling prioritized two candidate genes for blood pressure regulation (Dnm1, Tor1b), localized within the common congenic interval shared by SP.WKYGla3d and SP.WKYGla3f strains, and one candidate gene for salt-induced PP variability and renal pathology (Rabgap1), located within the region unique to the SP.WKYGla3d strain. Comparison of next-generation sequencing data identified variants within additional positional genes that are likely to affect protein function. CONCLUSION: This study has identified distinct intervals on RNO3-containing genes that may be important for blood pressure regulation and renal pathology during salt challenge.


Assuntos
Pressão Sanguínea/genética , Dinamina I/genética , Hipertensão/genética , Chaperonas Moleculares/genética , Locos de Características Quantitativas , Animais , Animais Congênicos , Mapeamento Cromossômico , Cromossomos de Mamíferos , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Hipertensão/patologia , Rim/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Análise de Sequência de DNA , Cloreto de Sódio na Dieta/administração & dosagem , Acidente Vascular Cerebral/patologia
12.
Nano Lett ; 17(2): 827-833, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28002672

RESUMO

A key task in the emerging field of bioelectronics is the transduction between ionic/protonic and electronic signals at high fidelity. This is a considerable challenge since the two carrier types exhibit intrinsically different physics and are best supported by very different materials types-electronic signals in inorganic semiconductors and ionic/protonic signals in organic or bio-organic polymers, gels, or electrolytes. Here we demonstrate a new class of organic-inorganic transducing interface featuring semiconducting nanowires electrostatically gated using a solid proton-transporting hygroscopic polymer. This model platform allows us to study the basic transducing mechanisms as well as deliver high fidelity signal conversion by tapping into and drawing together the best candidates from traditionally disparate realms of electronic materials research. By combining complementary n- and p-type transducers we demonstrate functional logic with significant potential for scaling toward high-density integrated bioelectronic circuitry.


Assuntos
Arsenicais/química , Gálio/química , Índio/química , Nanofios/química , Condutividade Elétrica , Eletrônica , Elétrons , Equipamentos e Provisões , Tamanho da Partícula , Polietilenoglicóis/química , Prótons , Semicondutores
13.
Nano Lett ; 16(10): 6213-6221, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27676609

RESUMO

The effective mass of electrons and holes in semiconductors is pivotal in determining the dynamics of carriers and their confinement energy in nanostructured materials. Surprisingly, this quantity is still unknown in wurtzite (WZ) nanowires (NWs) made of III-V compounds (e.g., GaAs, InAs, GaP, InP), where the WZ phase has no bulk counterpart. Here, we investigate the magneto-optical properties of InP WZ NWs grown by selective-area epitaxy that provides perfectly ordered NWs featuring high-crystalline quality. The combined analysis of the energy of free exciton states and impurity levels under magnetic field (B up to 29 T) allows us to disentangle the dynamics of oppositely charged carriers from the Coulomb interaction and thus to determine the values of the electron and hole effective mass. By application of B⃗ along different crystallographic directions, we also assess the dependence of the transport properties with respect to the NW growth axis (namely, the WZ c axis). The effective mass of electrons along c is me∥ = (0.078 ± 0.002) m0 (m0 is the electron mass in vacuum) and perpendicular to c is me⊥ = (0.093 ± 0.001) m0, resulting in a 20% mass anisotropy. Holes exhibit a much larger (∼320%) and opposite mass anisotropy with their effective mass along and perpendicular to c equal to mh∥ = (0.81 ± 0.18) m0 and mh⊥ = (0.250 ± 0.016) m0, respectively. While no full consensus is found with current theoretical results on WZ InP, our findings show trends remarkably similar to the experimental data available in WZ bulk materials, such as InN, GaN, and ZnO.

15.
Parasit Vectors ; 9(1): 425, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27484910

RESUMO

BACKGROUND: The cattle tick Rhipicephalus (Boophilus) microplus is an economically important parasite of livestock. Effective control of ticks using acaricides is threatened by the emergence of resistance to many existing compounds. Several continuous R. microplus cell lines have been established and provide an under-utilised resource for studies into acaricide targets and potential genetic mutations associated with resistance. As a first step to genetic studies using these resources, this study aimed to determine the presence or absence of two genes and their transcripts that have been linked with acaricide function in cattle ticks: ß-adrenergic octopamine receptor (ßAOR, associated with amitraz resistance) and ATP-binding cassette B10 (ABCB10, associated with macrocyclic lactone resistance) in six R. microplus cell lines, five other Rhipicephalus spp. cell lines and three cell lines representing other tick genera (Amblyomma variegatum, Ixodes ricinus and Hyalomma anatolicum). METHODS: End-point polymerase chain reaction (PCR) was used for detection of the ßAOR gene and transcripts in DNA and RNA extracted from the tick cell lines, followed by capillary sequencing of amplicons. Quantitative real-time PCR (qPCR) was performed to determine the levels of expression of ABCB10. RESULTS: ßAOR gene expression was detected in all Rhipicephalus spp. cell lines. We observed a second amplicon of approximately 220 bp for the ßAOR gene in the R. microplus cell line BME/CTVM6, derived from acaricide-resistant ticks. Sequencing of this transcript variant identified a 36 bp insertion in the ßAOR gene, leading to a 12-amino acid insertion (LLKTLALVTIIS) in the first transmembrane domain of the protein. In addition, nine synonymous SNPs were also discovered in R. appendiculatus, R. evertsi and R. sanguineus cell lines. Some of these SNPs appear to be unique to each species, providing potential tools for differentiating the tick species. The BME/CTVM6 cell line had significantly higher ABCB10 (P = 0.002) expression than the other R. microplus cell lines. CONCLUSIONS: The present study has identified a new ßAOR gene and demonstrated a higher ABCB10 expression level in the BME/CTVM6 cell line, indicating that tick cell lines provide a useful experimental tool for acaricide resistance studies and further elucidation of tick genetics.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Acaricidas/farmacologia , Proteínas de Artrópodes/genética , Doenças dos Bovinos/parasitologia , Resistência a Medicamentos , Receptores de Amina Biogênica/genética , Rhipicephalus/efeitos dos fármacos , Rhipicephalus/genética , Infestações por Carrapato/veterinária , Transportadores de Cassetes de Ligação de ATP/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/metabolismo , Bovinos , Dados de Sequência Molecular , Receptores de Amina Biogênica/metabolismo , Rhipicephalus/metabolismo , Alinhamento de Sequência , Infestações por Carrapato/parasitologia , Toluidinas/farmacologia
16.
Cell Death Dis ; 7(6): e2277, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27336721

RESUMO

Cardiac progenitor cells derived from adult heart have emerged as one of the most promising stem cell types for cardiac protection and repair. Exosomes are known to mediate cell-cell communication by transporting cell-derived proteins and nucleic acids, including various microRNAs (miRNAs). Here we investigated the cardiac progenitor cell (CPC)-derived exosomal miRNAs on protecting myocardium under oxidative stress. Sca1(+)CPCs-derived exosomes were purified from conditional medium, and identified by nanoparticle trafficking analysis (NTA), transmission electron microscopy and western blotting using CD63, CD9 and Alix as markers. Exosomes production was measured by NTA, the result showed that oxidative stress-induced CPCs secrete more exosomes compared with normal condition. Although six apoptosis-related miRNAs could be detected in two different treatment-derived exosomes, only miR-21 was significantly upregulated in oxidative stress-induced exosomes compared with normal exosomes. The same oxidative stress could cause low miR-21 and high cleaved caspase-3 expression in H9C2 cardiac cells. But the cleaved caspase-3 was significantly decreased when miR-21 was overexpressed by transfecting miR-21 mimic. Furthermore, miR-21 mimic or inhibitor transfection and luciferase activity assay confirmed that programmed cell death 4 (PDCD4) was a target gene of miR-21, and miR-21/PDCD4 axis has an important role in anti-apoptotic effect of H9C2 cell. Western blotting and Annexin V/PI results demonstrated that exosomes pre-treated H9C2 exhibited increased miR-21 whereas decreased PDCD4, and had more resistant potential to the apoptosis induced by the oxidative stress, compared with non-treated cells. These findings revealed that CPC-derived exosomal miR-21 had an inhibiting role in the apoptosis pathway through downregulating PDCD4. Restored miR-21/PDCD4 pathway using CPC-derived exosomes could protect myocardial cells against oxidative stress-related apoptosis. Therefore, exosomes could be used as a new therapeutic vehicle for ischemic cardiac disease.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose , Exossomos/metabolismo , MicroRNAs/metabolismo , Miocárdio/citologia , Miócitos Cardíacos/citologia , Células-Tronco/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Forma Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Exossomos/efeitos dos fármacos , Exossomos/ultraestrutura , Células HEK293 , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Modelos Biológicos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Ratos , Células-Tronco/efeitos dos fármacos
17.
Nano Lett ; 16(5): 3085-93, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27104870

RESUMO

Heat management mechanisms play a pivotal role in driving the design of nanowire (NW)-based devices. In particular, the rate at which charge carriers cool down after an external excitation is crucial for the efficiency of solar cells, lasers, and high-speed transistors. Here, we investigate the thermalization properties of photogenerated carriers by continuous-wave (cw) photoluminescence (PL) in InP and GaAs NWs. A quantitative analysis of the PL spectra recorded up to 310 K shows that carriers can thermalize at a temperature much higher than that of the lattice. We find that the mismatch between carrier and lattice temperature, ΔT, increases exponentially with lattice temperature and depends inversely on the NW diameter. ΔT is instead independent of other NW characteristics, such as crystal structure (wurtzite vs zincblende), chemical composition (InP vs GaAs), shape (tapered vs columnar NWs), and growth method (vapor-liquid-solid vs selective-area growth). Remarkably, carrier temperatures as high as 500 K are reached at the lattice temperature of 310 K in NWs with ∼70 nm diameter. While a population of nonequilibrium carriers, usually referred to as "hot carriers", is routinely generated by high-power laser pulses and detected by ultrafast spectroscopy, it is quite remarkable that it can be observed in cw PL measurements, when a steady-state population of carriers is established. Time-resolved PL measurements show that even in the thinnest NWs carriers have enough time (∼1 ns) after photoexcitation to interact with phonons and thus to release their excess energy. Nevertheless, the inability of carriers to reach a full thermal equilibrium with the lattice points to inhibited phonon emission primarily caused by the large surface-to-volume ratio of small diameter NWs.

18.
Vox Sang ; 110(1): 36-50, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26178308

RESUMO

BACKGROUND: A common national MTP was jointly implemented in 2011 by the national blood service (Blood Services Group) and seven participating acute hospitals to provide rapid access to transfusion support for massively haemorrhaging patients treated in all acute care hospitals. METHODS: Through a systematic clinical workflow, blood components are transfused in a ratio of 1:1:1 (pRBC: whole blood-derived platelets: FFP), together with cryoprecipitate for fibrinogen replacement. The composition of components for the MTP is fixed, although operational aspects of the MTP can be adapted by individual hospitals to suit local hospital workflow. The MTP could be activated in support of any patient with critical bleeding and at risk of massive transfusion, including trauma and non-trauma general medical, surgical and obstetric patients. RESULTS: There were 434 activations of the MTP from October 2011 to October 2013. Thirty-nine per cent were for trauma patients, and 30% were for surgical patients with heavy intra-operative bleeding, with 25% and 6% for patients with gastrointestinal bleeding and peri-partum haemorrhage, respectively. Several hospitals reported reduction in mean time between request and arrival of blood. Mean transfusion ratio achieved was one red cell unit: 0·8 FFP units: 0·8 whole blood-derived platelet units: 0·4 units of cryoprecipitate. Although cryoprecipitate usage more than doubled after introduction of MTP, there was no significant rise in overall red cells, platelet and FFP usage following implementation. CONCLUSION: This successful collaboration shows that shared transfusion protocols are feasible and potentially advantageous for hospitals sharing a central blood provider.


Assuntos
Transfusão de Sangue/métodos , Protocolos Clínicos , Guias de Prática Clínica como Assunto , Adulto , Transfusão de Sangue/normas , Hemorragia/epidemiologia , Hemorragia/terapia , Hospitais/estatística & dados numéricos , Humanos , Singapura , Reação Transfusional
19.
Neuroscience ; 311: 45-55, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26470809

RESUMO

The role of serotonin7 (5-HT7) receptors in the regulation of depression is poorly understood, particularly in Parkinson's disease-associated depression. Here we examined whether 5-HT7 receptors in the prelimbic (PrL) sub-region of the ventral medial prefrontal cortex (mPFC) involve in the regulation of depressive-like behaviors in sham-operated rats and rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. The lesion induced depressive-like responses as measured by the sucrose preference and forced swim tests when compared to sham-operated rats. Intra-PrL injection of 5-HT7 receptor agonist AS19 (0.5, 1 and 2 µg/rat) increased sucrose consumption, and decreased immobility time in sham-operated and the lesioned rats, indicating the induction of antidepressant-like effects. Further, intra-PrL injection of 5-HT7 receptor antagonist SB269970 (1.5, 3 and 6 µg/rat) decreased sucrose consumption, and increased immobility time, indicating the induction of depressive-like responses. However, the doses producing these effects in the lesioned rats were higher than those in sham-operated rats. Neurochemical results showed that intra-PrL injection of AS19 (2 µg/rat) increased dopamine, 5-hydroxytryptamine (5-HT) and noradrenaline (NA) levels in the mPFC, habenula and ventral hippocampus (vHip) in sham-operated and the lesioned rats; whereas SB269970 (6 µg/rat) decreased 5-HT levels in the habenula and vHip, and the levels of NA in the mPFC, habenula and vHip in the two groups of rats. The results suggest that 5-HT7 receptors in the PrL play an important role in the regulation of these behaviors, which attribute to changes in monoamine levels in the limbic and limbic-related brain regions after activation and blockade of 5-HT7 receptors.


Assuntos
Encéfalo/metabolismo , Transtorno Depressivo/metabolismo , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/psicologia , Receptores de Serotonina/metabolismo , Animais , Antidepressivos/farmacologia , Encéfalo/efeitos dos fármacos , Transtorno Depressivo/tratamento farmacológico , Sacarose Alimentar , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Norepinefrina/metabolismo , Oxidopamina , Transtornos Parkinsonianos/tratamento farmacológico , Ratos Sprague-Dawley , Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
20.
Sci Rep ; 5: 15339, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26469227

RESUMO

We propose the optical design for the absorptive element of photodetectors to achieve wavelength selective photo response based on resonant guided modes supported in semiconductor nanowires. We show that the waveguiding properties of nanowires result in very high absorption efficiency that can be exploited to reduce the volume of active semiconductor compared to planar photodetectors, without compromising the photocurrent. We present a design based on a group of nanowires with varying diameter for multi-color photodetectors with small footprint. We discuss the effect of a dielectric shell around the nanowires on the absorption efficiency and present a simple approach to optimize the nanowire diameter-dielectric shell thickness for maximizing the absorption efficiency.

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