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This study investigated the effects of dietary isoleucine (Ile) on growth performance, intestinal expression of amino acid transporters, protein metabolism-related genes and intestinal microbiota in starter phase Chinese yellow-feathered chickens. Female Xinguang yellow-feathered chickens (n = 1,080, aged 1 d) were randomly distributed to 6 treatments, each with 6 replicates of 30 birds. Chickens were fed diets with 6 levels of total Ile (6.8, 7.6, 8.4, 9.2, 10.0, and 10.8 g/kg) for 30 d. The average daily gain and feed conversion ratio were improved with dietary Ile levels (P < 0.05). Plasma uric acid content and glutamic-oxalacetic transaminase activity were linearly and quadratically decreased with increasing dietary Ile inclusion (P < 0.05). Dietary Ile level had a linear (P < 0.05) or quadratic (P < 0.05) effect on the jejunal expression of ribosomal protein S6 kinase B1 and eukaryotic translation initiation factor 4E binding protein 1. The relative expression of jejunal 20S proteasome subunit C2 and ileal muscle ring finger-containing protein 1 decreased linearly (P < 0.05) and quadratically (P < 0.05) with increasing dietary Ile levels. Dietary Ile level had a linear (P = 0.069) or quadratic (P < 0.05) effect on the gene expression of solute carrier family 15 member 1 in jejunum and solute carrier family 7 member 1 in ileum. In addition, bacterial 16S rDNA full-length sequencing showed that dietary Ile increased the cecal abundances of the Firmicutes phylum, and Blautia, Lactobacillus, and unclassified_Lachnospiraceae genera, while decreased that of Proteobacteria, Alistipes, and Shigella. Dietary Ile levels affected growth performance and modulated gut microbiota in yellow-feathered chickens. The appropriate level of dietary Ile can upregulate the expression of intestinal protein synthesis-related protein kinase genes and concomitantly inhibit the expression of proteolysis-related cathepsin genes.
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Galinhas , Microbioma Gastrointestinal , Animais , Feminino , Galinhas/fisiologia , Suplementos Nutricionais/análise , Isoleucina , Dieta/veterinária , Sistemas de Transporte de Aminoácidos/genética , Ração Animal/análiseRESUMO
The successful synthesis of superconducting infinite-layer nickelate thin films with the highest Tc ≈ 15 K has ignited great enthusiasm for this material class as potential analogs of the high-Tc cuprates. Pursuing a higher Tc is always an imperative task in studying a new superconducting material system. Here we report high-quality Pr0.82Sr0.18NiO2 thin films with Tconset ≈ 17 K synthesized by carefully tuning the amount of CaH2 in the topotactic chemical reduction and the effect of pressure on its superconducting properties by measuring electrical resistivity under various pressures in a cubic anvil cell apparatus. We find that the onset temperature of the superconductivity, Tconset, can be enhanced monotonically from ~17 K at ambient pressure to ~31 K at 12.1 GPa without showing signatures of saturation upon increasing pressure. This encouraging result indicates that the Tc of infinite-layer nickelates superconductors still has room to go higher and it can be further boosted by applying higher pressures or strain engineering in the heterostructure films.
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The Mn-based superconductor is rare owing to the strong magnetic pair-breaking effect. Here we report on the discovery of pressure-induced superconductivity in KMn_{6}Bi_{5}, which becomes the first ternary Mn-based superconductor. At ambient pressure, the quasi-one-dimensional KMn_{6}Bi_{5} is an antiferromagnetic metal with T_{N}≈75 K. By measuring resistance and ac magnetic susceptibility under hydrostatic pressures up to 14.2 GPa in a cubic anvil cell apparatus, we find that its antiferromagnetic transition can be suppressed completely at a critical pressure of P_{c}≈13 GPa, around which bulk superconductivity emerges and displays a superconducting dome with the maximal T_{c}^{onset}=9.3 K achieved at about 14 GPa. The close proximity of superconductivity to a magnetic instability in the temperature-pressure phase diagram of KMn_{6}Bi_{5} and an unusually large µ_{0}H_{c2}(0) exceeding the Pauli paramagnetic limit suggests an unconventional magnetism-mediated paring mechanism. In contrast to the binary MnP, the flexibility of the crystal structure and chemical compositions in the ternary AMn_{6}Bi_{5} (A=alkali metal) can open a new avenue for finding more Mn-based superconductors.
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We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu2+ moments and shows a large upper critical field comparable to the Pauli paramagnetic limit in EuTe2. In concomitant with the emergence of superconductivity with Tc ≈ 3-5 K above Pc ≈ 6 GPa, the antiferromagnetic transition temperature TN(P) experiences a quicker rise with the slope increased dramatically from dTN/dP = 0.85(14) K/GPa for P ≤ Pc to 3.7(2) K/GPa for P ≥ Pc. Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu2+ sublattice under moderate magnetic fields µ0H ≥ 2 T. Our findings establish the pressurized EuTe2 as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity.
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We studied the electronic Raman spectra of (Li_{1-x}Fe_{x})OHFeSe as a function of light polarization and temperature. In the B_{1g} spectra alone we observe the redistribution of spectral weight expected for a superconductor and two well-resolved peaks below T_{c}. The nearly resolution-limited peak at 110 cm^{-1} (13.6 meV) is identified as a collective mode. The peak at 190 cm^{-1} (23.6 meV) is presumably another collective mode since the line is symmetric and its energy is significantly below the gap energy observed by single-particle spectroscopies. Given the experimental band structure of (Li_{1-x}Fe_{x})OHFeSe, the most plausible explanations include conventional spin-fluctuation pairing between the electron bands and the incipient hole band and pairing between the hybridized electron bands. The absence of gap features in A_{1g} and B_{2g} symmetry favors the second case. Thus, in spite of various differences between the pnictides and chalcogenides, this Letter demonstrates the proximity of pairing states and the importance of band structure effects in the Fe-based compounds.
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Objective: To study the characteristics of the lens turbidity after long-term exposure to low intensity 635nm laser. Methods: Cluster sampling method was adopted to select 812 employees in a laser leveler workshop in a city of Guangdong Province from January 2014 to December 2018. They were divided into the control group, diffuse reflection (DR) group and direct vision (DV) group for retrospective observation and analysis of lens turbidity. The laser irradiation intensity of each group was investigated, the position and shape of lens opacity were analyzed, and the influencing factors were statistically analyzed with the repeated measurement data of dichotomy. Results: The laser irradiance and radiant exposure of DV group were between 0.72×10(-4) and 9.92×10(-4) mW/cm(2) and between 2.61×10(-2) and 1.53 J/cm(2), respectively. The subjects were mainly diagnosed with lens turbidity lesion, especially for the DV group. Most of lesions occurred in the pole and periphery of the anterior cortex. The lesions exhibited multipoint patterns with greyish white color. The turbidity rates in DV group (before work and work for 1, 2, 3 years) were 0%, 1.99% (8/402) , 4.98% (20/402) and 6.72% (27/402) , respectively, in the order of observation points. The statistical analysis of single factor effect showed that the turbidity rate was higher in DV group and higher in the second year in the DV group (P<0.01) . Multi-factor analysis of the laser effect on the lens showed that the main effect between groups, between the observation point were statistically significant (P<0.05) , but no statistical significance in the interaction between group×observation points (P>0.05) . Conclusion: Lens turbidity lesion can be caused by long-term exposure to low intensity 635 nm laser, so the product safety classification should be strictly strengthened. It is necessary to strengthen the protection of laser photochemical damage in the production process.
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Catarata , Lasers , Cristalino , Exposição Ocupacional , Humanos , Estudos RetrospectivosRESUMO
Objective: To explore the effects of different puberty development stages on thyroid morphology and function in women. Methods: From October to November 2017, a multi-stage cluster sampling method was used to select one junior high school in Minhang district of Shanghai, Haimen city of Jiangsu province, Yuhuan city of Zhejiang province and Deqing county of Zhejiang province respectively. A total of 491 girls in the first grade in 4 schools were included in the study. The subjects were examined with thyroid B-ultrasound and physical examination, and their morning random urine samples and fasting blood samples were collected to detect urinary iodine and thyroid function indexes. Puberty Development Self-rating Scale (PDS) was used to evaluate the stages of puberty; multiple linear regression models and logistic regression models were used to investigate the effects of different puberty stages on thyroid morphology and function. Results: There were differences in thyroid status among women at different stages of puberty. Thyroid volume, the rate of nodules and the level of FT4 were lowest in prepubertal period, followed by pubertal period and postpubertal period (P<0.05). TT3 and FT3 levels were highest in prepubertal period, followed by pubertal period and postpubertal period (P<0.001), and there was an opposite trend on the abnormal rate. TSH and TT4 levels were not affected by the stage of puberty (P>0.05). Multiple linear regression analysis and multivariate logistic regression analysis showed consistent results. There was a negative correlation between puberty development and TT3 and FT3 levels. For each 1 point increase in PDS, TT3 and FT3 levels decreased by 0.067 nmol/L and 0.170 nmol/L in Model 1, respectively, and decreased by 0.065 nmol/L and 0.162 nmol/L in Model 2, respectively. Compared with the prepubertal period, the TT3 and FT3 levels were lower in postpubertal period (Model 1: OR=0.337, 95%CI: 0.173-0.658; OR=0.283, 95%CI: 0.144-0.557; Model 2: OR=0.306, 95%CI: 0.155-0.605; OR=0.263, 95%CI: 0.132-0.524). Conclusions: The process of puberty is related to the thyroid status in women. The better matured during the puberty, the larger volume the thyroid was, more likely the thyroid nodules appeared, and the levels of TT3 and FT3 was much lower.
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Puberdade , Glândula Tireoide/anatomia & histologia , Glândula Tireoide/fisiologia , Adolescente , China , Feminino , HumanosRESUMO
The objective of current study was to investigate the effect of N-acetyl-l-methionine (NALM) supplementation on lactation performance and plasma variables in mid-lactating dairy cows. Forty-eight multiparous cows were blocked into 12 groups based on parity, days in milk, and milk production and were randomly assigned to 1 of the 4 treatments: 0, 15, 30, or 60 g/d of NALM per cow to supplement the basal diet. The experiment was conducted over a 13-wk period, with the first week as adaptation. The yields of milk, fat-corrected milk, and milk lactose were increased quadratically, and energy-corrected milk yield tended to increase with increased NALM supplementation in a quadratic manner. The dry matter intake, milk protein yield, milk fat yield, contents of milk composition (protein, fat, lactose, total solids, and milk urea nitrogen), feed efficiency, and body weight change were not affected by NALM supplementation. In addition, plasma methionine concentration was increased quadratically, and proline, total nonessential AA, and total AA concentrations were significantly higher in the 30 g/d group compared with that of the control group. However, other AA and total essential AA concentrations were not affected with supplementation of NALM. Adding NALM increased concentrations of total protein and globulin in plasma, but decreased plasma urea nitrogen concentration in a quadratic manner. Meanwhile, plasma malonaldehyde concentration decreased linearly as doses of NALM addition increased. Our results suggested that the supplementation of NALM improved milk yield and protein synthesis in the liver, and lowered lipid peroxidation in mid-lactating dairy cows.
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Bovinos/sangue , Dieta/veterinária , Suplementos Nutricionais , Lactação/efeitos dos fármacos , Metionina/análogos & derivados , Ração Animal/análise , Animais , Feminino , Metionina/metabolismo , Metionina/farmacologia , Leite/metabolismo , Proteínas do Leite/metabolismo , Paridade , Gravidez , Distribuição Aleatória , Ureia/metabolismoRESUMO
In order to elucidate pressure-induced second superconducting phase (SC-II) in A x Fe2-ySe2 (A = K, Rb, Cs, and Tl) having an intrinsic phase separation, we perform a detailed high-pressure magnetotransport study on the isoelectronic, phase-pure (Li1-xFe x )OHFe1-ySe single crystals. Here we show that its ambient-pressure superconducting phase (SC-I) with a critical temperature Tc ≈ 40 K is suppressed gradually to below 2 K and an SC-II phase emerges above Pc ≈ 5 GPa with Tc increasing progressively to above 50 K up to 12.5 GPa. Our high-precision resistivity data uncover a sharp transition of the normal state from Fermi liquid for SC-I to non-Fermi liquid for SC-II phase. In addition, the reemergence of high-Tc SC-II is found to accompany with a concurrent enhancement of electron carrier density. Without structural transition below 10 GPa, the observed SC-II with enhanced carrier density should be ascribed to an electronic origin presumably associated with pressure-induced Fermi surface reconstruction.
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Dietary patterns may interfere with the efficacy of herbal intervention. Our results demonstrated the protective effects of Salvia miltiorrhiza aqueous extract (SMA) on bone metabolism were influenced by levels of dietary fat and sucrose in ovariectomized (OVX) rats through its actions on attenuating lipid deposition and oxidative stress in rats. INTRODUCTION: Salvia miltiorrhiza (SM), also known as Danshen, has been tested as an osteoporosis treatment in a series of small, short human trials that generally report improvements in bone property. However, dietary patterns may interfere with the effects of herbal intervention. We hypothesized that dietary fat and sucrose levels could influence the effects of SM supplementation on bone in estrogen-deficient animals. METHODS: Six-month-old Sprague-Dawley sham or OVX rats were fed either a low-saturated fat-sucrose (LFS, a diet that was similar in composition to normal rat chow) or a high-fat-sucrose (HFS) diet and OVX rats were treated (8 rats/group) with SM aqueous extract (SMA, 600 mg/kg/day), 17ß-estradiol (1 mg/kg/day), or vehicle for 12 weeks. RESULTS: SMA significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats, but not in LFS-fed OVX rats. SMA greatly reduced lipid deposition and malondialdehyde levels, improved the activities of superoxide dismutase, catalase, and glutathione peroxidase in the livers of HFS-fed OVX rats. SMA could directly improve the proliferation and differentiation in vitro in an H2O2-induced preosteoblast cell model by attenuating cellular reactive oxygen species levels. CONCLUSIONS: The protective effects of SMA on bone metabolism were influenced by dietary fat and sucrose levels in OVX rats. The ability of SMA to reduce bone loss in HFS-fed OVX rats was associated with the attenuation of lipid deposition and oxidative stress levels.
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Dieta Hiperlipídica , Gorduras na Dieta/farmacologia , Sacarose Alimentar/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Osteoporose Pós-Menopausa/prevenção & controle , Fitoterapia/métodos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/efeitos dos fármacos , Sacarose Alimentar/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Medicamentos de Ervas Chinesas/farmacologia , Ácidos Graxos/administração & dosagem , Ácidos Graxos/farmacologia , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Salvia miltiorrhiza , Útero/patologiaRESUMO
Objective: In this study, we tested platelet count (PC), prothrombin time (PT), activated partial thromboplastin time (APTT), and other indicators of coagulation function, and revealed their difference in patients with traumatic brain injury (TBI) between plain and plateau area. Base on the results, we may provide research basis for the therapy of TBI associated coagulopathy in different areas. Methods: 151 TBI patients from Tianjin Medical University General Hospital, and 74 from People's Hospital of Tibet Autonomous Region in the period from Dec 2013 to Dec 2015 were enrolled.Coagulation function, including PC, platelet distribution width (PDW), mean platelet volume (MPV), platelet - large cell ratio (P- LCR), PT, APTT, fibrinogen (FIB), and D- Dimer were tested within 8 h. The difference in patients with TBI between plain and plateau areas were compared and analyzed. Results: Compared with plain area, the PC of patients with TBI in plateau area is lower [(168±49)×109/L vs (196±72)×109/L, P<0.05], while PT and APTT were extended [(13.5±1.3) s vs (12.0±4.0) s, (38±4) s vs(27±6) s, P<0.01]. On the other hand, FIB increases [(3.1±1.2) g/L vs (2.6±1.0) g/L, P<0.01] and D-Dimer decreases [(3.1±3.3) µg/L vs (4.7±3.6) µg/L, P<0.01] in plateau area compared with plain area. Conclusion: Due to the people of plateau area living in hypoxia state, the coagulation function is activated for a long time.Once TBI happens, the platelets and coagulation factors may be excessive consumption, resulting in hypocoagulable state and high risk of rebleeding, while the fibrinolysis system in patients with TBI of plateau area is not activated obviously.Therefore, it should give full consideration to these differences in the treatment of patients with TBI in plateau area, instead of directly copying the standard therapy of the people in plain area.The treatment recommendations should primarily supplement coagulation materials, and antifibrinolytics may unlikely have the therapy effect.
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Coagulação Sanguínea , Lesões Encefálicas Traumáticas , Transtornos da Coagulação Sanguínea , Testes de Coagulação Sanguínea , Produtos de Degradação da Fibrina e do Fibrinogênio , Fibrinogênio , Humanos , Tempo de Tromboplastina Parcial , Contagem de Plaquetas , Tempo de Protrombina , TibetRESUMO
Objective: To investigate the influence of body mass index (BMI) and its change on the incidence of type 2 diabetes mellitus (T2DM) in an adult cohort. Methods: A total of 3 043 subjects randomly selected among those without T2DM at baseline survey from the Rural Deqing Health Cohort Study were included into this study and follow up was conducted for 1 867 of them from July to November 2015. The subjects were divided into 3 groups according to their baseline BMI, normal group (BMI<24.0), overweight group (BMI: 24.0-27.9) and obese group (BMI≥28.0) and the subjects with stable weight (BMI change of-0.05 to + 0.05 per year) were used as the referent category. Cox proportional model was used to estimate associations between BMI, its changes and T2DM. Results: With an average of (8.68±1.25) person years, 213 new T2DM cases, including 125 females were detected, and incidence density was 13.14 per 1 000 person years. After adjusted for other covariates, the risk for incidence of T2DM was significantly higher in subjects with baseline BMI≥28.0 kg/m2 than those with baseline BMI<24.0 kg/m2 (aHR=2.12, 95% CI: 1.22-3.68), and weight gains were strongly associated with the incidence of T2DM in those with baseline BMI< 24.0 kg/m2 (aHR=2.21, 95%CI:1.17-4.17). Conclusion: Both BMI and its change were significantly associated with incidence of T2DM, especially in the population with BMI<24.0 kg/m2 at baseline.
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Índice de Massa Corporal , Diabetes Mellitus Tipo 2/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade , Sobrepeso , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Aumento de PesoRESUMO
Sturgeons (Acipenser schrenckii) are of high evolutionary, economic, and conservation value, and caviar isone of the most valuable animal food products in the world. The Illumina HiSeq2000 sequencing platform was used to construct testicular and ovarian transcriptomes to identify genes involved in reproduction and sex determination in A. schrenckii. A total of 122,381 and 114,527 unigenes were obtained in the testicular and ovarian transcriptomes, respectively, with average lengths of 748 and 697 bp. A total of 46,179 genes were matched to the non-redundant nr database. GO (31,266), KEGG (39,712), and COG analyses (20,126) were performed to identify potential genes and their functions. Twenty-six gene families involved in reproduction and sex determination were identified from the A. schrenckii testicular and ovarian transcriptomes based on functional annotation of non-redundant transcripts and comparisons with the published literature. Furthermore, 1309 unigenes showed significant differences between the testes and ovaries, including 782 genes that were up-regulated in the testes and 527 that were up-regulated in the ovaries. Eleven genes were involved in reproduction and sex determination mechanisms. Furthermore, 19,065 simple sequence repeats (SSRs) were identified in the expressed sequence tagged dataset, and 190,863 and 193,258 single nucleotide polymorphisms (SNPs) were obtained from the testicular and ovarian transcriptomic databases, respectively. This study provides new sequence information about A. schrenckii, which will provide a basis for the further study of reproduction and sex determination mechanisms in Acipenser species. The potential SSR and SNP markers isolated from the transcriptome may shed light on the evolution and molecular ecology of Acipenser species.
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Proteínas de Peixes/genética , Peixes/genética , Ovário/metabolismo , Reprodução/genética , Processos de Determinação Sexual , Testículo/metabolismo , Transcriptoma , Animais , Feminino , Proteínas de Peixes/metabolismo , Peixes/crescimento & desenvolvimento , Peixes/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Masculino , Anotação de Sequência Molecular , Ovário/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único , Testículo/crescimento & desenvolvimentoRESUMO
In China, covering developing apple (Malus × domestica) fruit with paper bags is a standard production practice. The fruit are usually covered from May to October to exclude pests and rain-dispersed pathogens and reduce pesticide residue at harvest. From 2010 to 2012, a fruit spot disease was observed on bagged fruit and caused 1 to 30% annual yield losses in most orchards in Shandong Province. Affected fruit were covered with red-brown, sunken, circular lesions 2 to 20 mm in diameter with dark violet edges often surrounded by a red halo. In many cases, the lesion cracked and pinkish mycelium was observed within the cracks. Isolations were made from bagged fruit from 12 orchards in October 2010 to 2012. Fungal isolations were made onto potato dextrose agar (PDA) medium. Two strains were consistently obtained from isolates. Strain 1 produced conidia assembled in head. Conidia were ellipsoidal to ovoid and 2.1 to 7.5 × 1.1 to 3.0 µm. Colonies were whitish with some pink and powdery on PDA. String 2 produced conidia in a long chain. Conidia were spindle-shaped with apiculate at both ends and 2.1 to 6.6 × 1.3 to 3.8 µm. Colonies were whitish at the beginning and grayish later and powdery on PDA. To further confirm the identity of the isolated fungus, the large subunit (LSU), the small subunit (SSU), and the internal transcribed spacer (ITS) sequences of ribosomal DNA, and the ß-tubulin gene (ß-tubulin), were amplified and sequenced with the primers V9G/LR5, NS1/NS24, ITS1/ITS4, and Bt1a/Bt1b, respectively. LSU (GenBank Accession Nos. KJ194115 and KJ194116), SSU (KJ194117 and KJ194118), ITS (KF225143 and KF225144), and ß-tubulin (KF225145 and KF225146) sequences didn't have any variation between the two strains sequenced. Phylogenetic analyses of each of the examined genes indicated a high similarity (>99%) with Acremonium sclerotigenum (CBS 384.65 HQ232129). Based on the sequence data and the morphology, we identified the fungus as A. sclerotigenum (1,2). To confirm pathogenicity, a spore suspension (1 × 104 conidia per ml) was made from each of the strains isolated. Strains were subsequently inoculated on to 10 mature apple fruit by wounding them to a depth of 2 mm with an acupuncture needle. Inoculation with sterile distilled water was included as a control. Prior to inoculation, all fruit were surface-sterilized with 75% alcohol. Lesions developed on fruit inoculated with the putative pathogen 10 days after incubation in >90% humidity chamber at 25°C. The fungi that were isolated from the infected fruit were identical to the inoculated strains. No lesions developed on the control fruit. This is the first report of brown spot disease caused by A. sclerotigenum in apple and in bagged fruit production. Given that brown spot disease symptoms were usually observed in September after long periods of rain, management efforts need to focus on protecting bagged fruit before harvest. References: (1) H. Perdomo et al. J. Clin. Microbiol. 49:243, 2011. (2) R. C. Summerell et al. Stud. Mycol. 68:139, 2011.
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Gamma-Fe2.6Ni1.4 nanoparticles were prepared by the arc-discharge method as the precursor and its nitride counterpart of gamma'-Fe2.6Ni14N nanoparticles was synthesized directly through a thermal ammonolysis reaction at the temperature of 673 K for two hours. The resultant product was identified as a homogeneous ternary nitride with nearly spherical shape and average size of about 60.0 nm. The electromagnetic characteristics of gamma'-Fe2.6Ni1.4N derivant and gamma-Fe2.6Ni1.4 precursor have been studied in the frequency range of 2-18 GHz. Compared with the precursor, gamma'-Fe2.6Ni1.4N nanoparticles exhibits an enhanced electromagnetic absorption property resulted from the increased dielectric loss by nitriding process. The optimal reflection loss (RL) of gamma'-Fe2.6Ni1.4N nanoparticles/paraffin composite can reach -39.9 dB at 5.2 GHz in a thickness of 2.29 mm, and the frequency band corresponding RL < -10 dB is over 2.6-18 GHz in the thickness range of 0.78-4.20 mm.
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Hypoxia, frequently found in the center of solid tumors, may lead to enhance the production of key factor in cell survival, invasion, angiogenesis and loss of apoptosis. The low oxygen tension in hypoxic tumors is also known to interfere with the efficacy of chemotherapy, but the underlying mechanisms are not very clear. Paclitaxel (PTX) is an active agent used in breast cancer chemotherapy, which disturbs microtubule dynamics and impairs the transition of cells from metaphase to anaphase in mitosis, leading to cell death by apoptosis. In the present study, we try to determine whether hypoxia can decrease the chemosensitivity of human breast carcinoma cells to PTX and elucidate the underlying mechanism. We found that hypoxia could decrease PTX-induced cell death and G(2)/M arrest. Furthermore, our results showed that hypoxia inhibit PTX-induced soluble tubulin polymerized. In addition, we also found hypoxia could suppress PTX-induced cell cycle protein-cyclin B1 expression in MCF-7 cells. To further investigate whether the inhibitory effect of hypoxia on PTX-induced cell death is mediated by decreasing levels of cyclin B1, cyclin B1-transfected MCF-7 cells were used under hypoxic condition. The data showed that the hypoxia-based decreasing chemosensitivity of breast cancer cells to PTX was reversed by cyclin B1. We also found that overexpression of cyclin B1 could significantly increase the sensitivity of MCF-7 cells to PTX by stimulating soluble polymerized tubulin. Overall, hypoxia decreases cyclin B1, which could in turn reverse hypoxia-induced decreasing chemosensitivity to PTX in breast cancer cell line MCF-7.
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Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Ciclina B1/metabolismo , Paclitaxel/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologiaRESUMO
A new destructive apple disease, causing black spots and necrotic lesions on leaves and defoliation on cvs. Gala and Golden Delicious (Malus × domestica Borkh.), was observed in August 2011 in Fengxian, Jiangsu Province, China. More than 90% of trees of those cultivars in the area were defoliated by the disease and almost no leaves were left on trees before harvest. The disease was similar to Glomerella leaf spot reported first in Brazil in 1988 (2) and in the United States in 1998 (1) on cvs. Gala and Golden Delicious. The initial symptom was small black lesions on leaves. Above 30°C, the lesions developed quickly and grew to 2 to 3 cm, with a blurred edge. Diseased leaves became dark and were shed. At lower temperatures, the black lesions stopped enlarging after 5 to 6 days and formed large necrotic spots with clear edges; these leaves gradually grew yellow and were shed. When incubated at 30°C and 100% relative humidity for 1 to 2 days, the black lesions produced a mass of saffron-yellow conidia. On fruit, the pathogen only caused circular, necrotic, sunken, red-bordered lesions 2 to 3 mm in diameter, which was different from bitter rot. Three monospored cultures were isolated from diseased leaves and new conidia were obtained from isolates. The colony, with abundant mycelium, was white but turned gray to black. Conidia were 12 to 17 × 5 to 7 µm, and were cylindrical with rounded ends. After germination, conidia formed appressoria, oval, or circular cells with black thick walls 7 to 12 × 5 to 7 um. Based on morphological characteristics, the pathogen was putatively identified as Glomerella cingulata. The conidia were inoculated in vitro on leaves of cvs. Gala and Fuji by dripping a suspension of about 104 conidia/ml of water onto upper leaf surfaces. Dark necrotic lesions were observed on all inoculated Gala leaves, which were similar to those observed in orchards, after 4 days incubation in a chamber at 30°C with 100% humidity. Only small black lesions, about 1 to 2 mm in diameter, were observed on Fuji leaves. No symptoms developed on leaves inoculated with distilled water. The internal transcribed spacer (ITS) region of ribosomal DNA and part of the 18S and 28S ribosomal RNA of the three isolates were amplified with the universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-CCTCCGCTTATTGATATGC-3'). The amplified ITS sequences confirmed that the three isolates belonged to the same species, with only one base pair variation among sequences. The nucleotide sequence of isolate 1 and 2 was deposited in GenBank (JN714400 and JN714401). BLAST analysis showed that the sequence had 99% homology with the sequence of G. cingulata (EU008836), the causal agent of Glomerella leaf spot. However, the sequence of isolate 1 had 100% homology with that of G. cingulata (HQ845103.1) isolated from walnut in Shandong, China, while the sequence of isolate 2 had 100% homology with that of G. cingulata (HM015004.1) isolated from sweet pepper in Taiwan. Results suggested the disease is Glomerella leaf spot and the causal agent is G. cingulata. The disease will eliminate sensitive apple cultivars, such as Gala, from wet, warm production areas if effective control measures are not developed within a few years. To our knowledge, this was the first finding of the disease in China and will provide useful information for developing effective control strategies. References: (1) E. González and T. B. Sutton. Plant Dis. 83:1074, 1999. (2) T. B. Sutton and R. M. Sanhueza. Plant Dis. 82:267, 1998.
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OBJECTIVE: To examine the sensitivity and specificity of HbA1c testing for the diagnosis of type 2 diabetes in high-risk adults in China and to compare the cardiaovascular risk factors between 2 groups of patients with glycemic status classified by the 2 different tests. RESEARCH DESIGN AND METHOD: From a cross-sectional survey of prevalence of diabetes in China, we selected adults from the Jinan area of Shandong without known diabetes who underwent OGTT and HbA1c testing on the same day. Cardiovascular risk factors (blood pressure, body mass index, lipid levels) were compared among the subjects divided into 4 groups according to the 2 diabetes diagnostic criteria: true-diabetes, HbA1c-diagnosed diabetes, OGTT-diagnosed diabetes, and nondiabetes. RESULTS: Among 701 subjects, 65 cases of diabetes were diagnosed by HbA1c ≥6.5% and 94 cases by OGTT. Comparing with OGTT,the sensitivity with level of HbA1c >6.5% was 48.2% and the specificity 97.8%. In total, 30.7% of subjects with HbA1c ≥6.5% were not classified as having diabetes by OGTT criteria, and 52% of subjects with diabetes according to OGTT criteria would be considered nondiabetic by HbA1c recommended criteria. The OGTT- and HbA1c-diabetes groups showed the same cardiovascular risk factors, the levels of which were higher than that for the nondiabetes group. CONCLUSIONS: We found high specificity and low sensitivity with use of HbA1c level ≥6.5% to diagnose diabetes mellitus. The HbA1c test and OGTT did not reach full concordance. The 2 diagnostic criteria reflect similar levels of cardiovascular risk factors.
Assuntos
Povo Asiático , Diabetes Mellitus Tipo 2/diagnóstico , Técnicas de Diagnóstico Endócrino , Hemoglobinas Glicadas/análise , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Teste de Tolerância a Glucose/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
Cherry is a main fruit tree species in Shandong Peninsula, which is one of the most important cherry-production areas of China. A stem canker disease was first noted in a 15-year-old cherry orchard in Yantai, Shandong Peninsula in May 2009. Canker and branch dieback were the main symptoms of the disease and cracks often appeared at the margins of sunken cankers, which exposed the wooden stem. In later stages from April to May, black pycnidia were observed on the surface of cankered bark and cirri containing α-conidia were extruded under wet conditions. Wooden tissue under the diseased bark was dark brown, in contrast to the healthy tissue that was yellowish green. On the basis of morphological characteristics, the pathogen was putatively identified as Phomopsis perniciosa (1). Pycnidia were smaller in naturally infected branches than when produced on potato dextrose agar (PDA) medium (180 to 365 × 65 to 226 µm). Cultures of the pathogen appeared creamy white with concentric rings on PDA at 25°C and a mass of α-conidia (5.75 to 11.13 × 2.08 to 3.46 µm) and ß-conidia (31.24 to 34.68 × 1.45 to 1.82 µm) were produced within 3 weeks. Alpha-conidia were hyaline, fusiform-elliptic to oblong-elliptic, and biguttulate. Beta-conidia were hyaline and unicellular, filiformia, leviter arcuata vel hamata. Total DNA was extracted from three monoconidial isolates collected from different infected trees. The internal transcribed spacer (ITS) region was amplified using the universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-CCTCCGCTTATTGATATGC-3'). The ITS amplicons were sequenced (582 bp) from three isolates and no nucleotide variation was observed. BLAST analysis of the obtained ITS sequences showed that isolate 230101 had 99% homology with a Phomopsis sp. (GenBank Accession No. AB302248) isolated from fruit trees in Japan. The nucleotide sequence from isolate 230101 has been deposited in GenBank (Accession No. JF812647). Pathogenicity of the isolate was confirmed by inoculating branches of 3-year-old cherry trees with either conidia or hyphae. Inoculations were performed by making an incision with a sterile scalpel at the dissected area to expose the tissue under the bark. An agar plug (4 × 4 mm) containing 5-day-old cultured hyphae or 50 µl of a conidium suspension containing 106 α-conidia per ml was placed on each of the inoculation sites, wrapped with moist cheesecloth, and sealed with Parafilm. Control trees were treated similarly with sterile blocks of PDA or water, respectively. For each inoculation technique, five shoots were inoculated and the inoculation treatments were replicated three times. All inoculated and control trees were kept in a greenhouse and watered as needed. After 10 days, cankers and necrotic lesions developed on all shoots inoculated with P. perniciosa and the control trees did not display any symptoms. The same pathogen was reisolated from symptomatic branches. Phomopsis spp. are known to cause cankers and dieback of several woody hosts (2), but no reports have been found that the pathogen causes cherry canker and dieback in China. References: (1) P. K. Chi et al. Flora Fungorum Sinicorum-Phomopsis 34:127, 2007. (2) D. P. Weingartner and E. J. Klos. Phytopathology 65:105, 1975.
RESUMO
The chemokines are a superfamily of chemotactic cytokines playing an important role in leukocyte chemotaxis. Here, a turbot head kidney cDNA library was constructed in which KC70 was identified as a CC chemokine. Unknown 5' and 3' parts of the cDNA were amplified by 5' and 3' rapid amplification of cDNA ends (RACE). The complete cDNA of KC70 contains a 59-bp 5' UTR, a 336-bp ORF, and a 152-bp 3' UTR. Four exons and three introns were identified in KC70. Phylogenetic analysis showed that KC70 was similar to CCL19. In normal turbot KC70 was expressed in all tissues except brain and skin. Infection of turbot with pathogenic bacteria significantly increased expression of KC70 in the liver. Expression of KC70 in head kidney first increased and then decreased after bacterial challenge. No significant change was observed in the spleen after bacterial challenge. During embryonic development, KC70 was highly expressed after the gastrula stage. These results indicated KC70 plays important and multiple roles in turbot immune response.