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The objective of this study was to determine quarters requiring antimicrobial treatment using either a benchtop somatic cell counter or culture with gram-positive selective media and compare the outcomes in these cows to those receiving blanket dry cow therapy (BDCT) in a randomized, controlled trial. We evaluated 2 novel methods of identifying cows with intramammary infections followed by selective antimicrobial treatment at a commercial dairy farm to determine their usefulness in decreasing antibiotic usage during the dry period without significant detrimental effects on milk quality and production. Cows (n = 840) were randomly allocated to one of 3 groups (BDCT, gram-positive selective media culture-based selective dry cow therapy [C-SDCT], and somatic cell count-based SDCT [S-SDCT]) the day before dry-off, and quarter-level milk samples (QLMS) were collected. The QLMS from cows in the S-SDCT group were evaluated using the cell counter, and quarters were treated if SCC was ≥200,000 cells/mL, whereas the QLMS from cows in the C-SDCT group were cultured, and quarters were treated if the culture showed growth. All cows in the BDCT received antimicrobial therapy, and all cows received an internal teat sealant regardless of treatment group. Outcomes measured were first and second DHIA test SCC, milk production through 60 DIM, cows leaving the farm, clinical mastitis, and bacteriologic new infections in a subset of quarters. Cows in both SDCT groups had fewer antimicrobial treatments than cows in the BDCT group as was expected, and cows in the C-SDCT group had fewer treatments than those in the S-SDCT group. Cows in both SDCT groups had a higher linear score at the first DHIA test (BDCT: 1.8, S-SDCT: 2.2, C-SDCT: 2.2); however, we found no other differences between groups regarding any other outcomes measured. Although antimicrobial use was significantly reduced, farms should use caution in adopting the benchtop analyzer and the selective media described in this study as ways to identify infected cows for dry cow therapy because they may result in increased linear scores early in lactation.
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Lactação , Mastite Bovina , Leite , Animais , Bovinos , Feminino , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Contagem de Células/veterinária , Leite/citologia , Antibacterianos/uso terapêuticoRESUMO
The objectives of this study were to determine the effects of GnRH at the time of artificial insemination (AI) on ovulation, progesterone 7 d post-AI, and pregnancy in cows detected in estrus using traditional methods (tail chalk removal and mount acceptance visualization) or an automated activity-monitoring (AAM) system. We hypothesized that administration of GnRH at the time of AI would increase ovulation rate, plasma progesterone post-AI, and pregnancy per AI (P/AI) in cows detected in estrus. In experiment 1, Holstein cows (n = 398) were blocked by parity and randomly assigned to receive an injection of GnRH at the time of estrus detection/AI (GnRH, n = 197) or to remain untreated (control, n = 201) on 4 farms. The GnRH was administered as 100 µg of gonadorelin acetate. Ovarian structures and plasma progesterone were assessed in a subset of cows (GnRH, n = 52; control, n = 55) in experiment 1 at the time of AI and 7 d later. In experiment 2, a group of 409 cows in an AAM farm were enrolled as described for experiment 1 (GnRH, n = 207; control, n = 202). Data were categorized for parity (primiparous vs. multiparous), season (cool vs. warm), number of services (first vs. > first), DIM (>150 DIM vs. ≤150 DIM), and for AAM cows in experiment 2 for activity level (high: 90-100 index vs. low: 35-89 index). Pregnancy diagnosis was performed between 32 and 45 d post-AI (P1) and 60 to 115 d post-AI (P2). In experiment 1, there was no difference in plasma progesterone at day of estrus detection (control = 0.09 ng/mL vs. GnRH = 0.16 ng/mL), 7 d later (control = 2.03 ng/mL vs. GnRH = 2.18 ng/mL), and ovulation rate (GnRH = 83.2% vs. control = 77.9%) between treatments. There were no effects of GnRH in experiment 1 for P/AI at P1 (control = 43.3% vs. GnRH = 38.6%), P2 (control = 38.4% vs. GnRH = 34.5%), and for pregnancy loss (control = 9.8% vs. GnRH = 8.2%). In experiment 2, there were no effects of GnRH for P/AI at P1 (control = 39.6% vs. GnRH = 40.1%), P2 (control = 35.0% vs. GnRH = 37.4%), and for pregnancy loss (control = 9.5% vs. GnRH = 6.2%). There was a tendency for a parity effect on P/AI for P1, but not P2 or for pregnancy loss. High-activity cows had greater P/AI in P1 (low activity = 27.9% vs. high activity = 44.1%), P2 (low activity = 21.8% vs. high activity = 41.2%), and lower pregnancy loss (low activity = 20.7% vs. high activity = 5.1%), but there were no interactions between treatment and activity level. The current study did not support the use of GnRH at estrus detection to improve ovulatory response, progesterone 1 wk post-AI, and P/AI. More research is needed to investigate the relationship between GnRH at the time of AI and activity level in herds using AAM systems.
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Detecção do Estro , Hormônio Liberador de Gonadotropina , Animais , Bovinos , Dinoprosta , Estro , Sincronização do Estro , Feminino , Inseminação Artificial/veterinária , Lactação , Gravidez , ProgesteronaRESUMO
The objective of this study was to assess the effects of treatment with propylene glycol (PG) and cyanocobalamin (B12) on health, milk production, and reproductive outcomes of cows diagnosed with hyperketonemia (HK), hypoglycemia (HG), or concurrent HKHG. Glucose and ß-hydroxybutyric acid (BHBA) concentrations were assessed in whole blood using a handheld device in lactating dairy cows (n = 2,418) between 3 and 9 d postpartum. Cows categorized as HK (n = 232, BHBA ≥1.2 mmol/L), HG (n = 161, glucose ≤2.2 mmol/L), and concurrent HKHG (n = 204, BHBA ≥1.2 mmol/L, and glucose ≤2.2 mmol/L) were randomized to receive treatment or to remain untreated (control). Treatment consisted of a single dose of B12 (10 mg, intramuscularly) and 300 mL of PG orally for 5 d, starting on the day of cow-side testing. Milk production, health, and reproductive outcomes were analyzed according to groups. Statistical analysis was carried out using SAS version 9.4 (SAS/STAT, SAS Institute Inc.). Treatment in HG cows decreased clinical ketosis, increased milk production in the fifth week of lactation for multiparous cows, and tended to increase 305-d mature-equivalent milk yield (305ME) for primiparous cows compared with untreated cows with the same metabolic profile. For cows with HKHG, treatment increased 305ME in multiparous cows and tended to increase 305ME in primiparous cows. No differences were found for treatment among any of the metabolic groups regarding reproductive outcomes, nor were any treatment effects found among HK cows. Glycemic status may help identify metabolically challenged early postpartum dairy cows, which may have differential response to PG and B12 treatment.
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Doenças dos Bovinos , Hipoglicemia , Cetose , Feminino , Bovinos , Animais , Lactação/fisiologia , Ácido 3-Hidroxibutírico , Leite/metabolismo , Doenças dos Bovinos/metabolismo , Cetose/tratamento farmacológico , Cetose/veterinária , Propilenoglicol/farmacologia , Hipoglicemia/veterinária , Período Pós-Parto , Glucose/metabolismo , Vitamina B 12/farmacologiaRESUMO
The objectives of this study were to determine the effects of nerve growth factor-ß (NGF), purified from bulls' seminal plasma and administered at the time of artificial insemination (AI), on progesterone post-AI, interferon-stimulated genes (ISG), and pregnancy per AI (P/AI) for lactating Holstein dairy cows enrolled in a timed-AI protocol. We hypothesized that administration of NGF at the time of AI would increase plasma progesterone post-AI, upregulate relative abundance of ISG, and improve P/AI in lactating dairy cows. Holstein cows (n = 557) from a single commercial dairy farm were blocked by parity and randomly assigned to receive an intramuscular injection containing 296 µg of bovine purified NGF at the time of AI, diluted in 2 mL of phosphate-buffered saline (NGF: n = 275), or receive only the 2 mL of phosphate-buffered saline (control: n = 282). Plasma progesterone and corpus luteum size were assessed in a subset of cows (NGF: n = 32; control: n = 36) at d 7, 14, and 19 post-AI. Relative mRNA abundance of ISG (ISG15, MX1, MX2, and RTP4) was assessed in peripheral blood leukocytes on d 19 post-AI. Pregnancy diagnosis was performed at 37 and 65 d post-AI. There was an interaction effect between treatment and parity for plasma progesterone; however, plasma progesterone and ISG did not differ between treatments. There were no effects of NGF for P/AI at 37 d post-AI (NGF = 40.0% vs. control = 41.6%), 65 d post-AI (NGF = 36.0% vs. control = 38.1%), and for pregnancy loss (NGF = 8.4% vs. control = 7.7%). The current study revealed that effects to NGF in lactating Holstein cows were minor and contingent with parity for progesterone, and no improvement in ISG relative abundance and P/AI were observed.
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Sincronização do Estro , Progesterona , Animais , Bovinos , Ensaios Clínicos Veterinários como Assunto , Dinoprosta , Sincronização do Estro/métodos , Feminino , Hormônio Liberador de Gonadotropina , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Lactação , Masculino , Fator de Crescimento Neural/farmacologia , Fosfatos , GravidezRESUMO
The objective of this prospective cohort study was to characterize the metabolic profile, health, milk production, and reproductive outcomes of cows diagnosed with hyperketonemia (HK; ß-hydroxybutyrate ≥1.2 mmol/L), hypoglycemia (HG; glucose ≤2.2 mmol/L), or concurrent HK and HG (HKHG). Glucose and ß-hydroxybutyrate concentrations in whole blood were assessed using a handheld device (Precision Xtra, Abbott Laboratories) in lactating dairy cows (n = 2,418) between 3 and 9 d postpartum. Cows were categorized into 4 groups: no HK or HG (healthy; Norm = 1,821), HK only (HK = 232), HG only (HG = 161), and concurrent HK and HG (HKHG = 204). Subsequent milk production, along with health and reproductive outcomes, as recorded by farm personnel, were analyzed according to metabolic category. Serum collected on the day of cow-side diagnosis of hyperketonemia and hypoglycemia was evaluated for total calcium (tCa), magnesium (Mg), nonesterified fatty acids (NEFA), triglycerides (TG), and urea using an automated chemistry analyzer (Randox Daytona; Randox Laboratories Ltd.). Statistical analysis was carried out using SAS version 9.4 (SAS Institute Inc.). Hyperketonemia in multiparous cows was associated with greater incidence of metabolic abnormalities (hypomagnesemia, hypocalcemia, and elevated NEFA and urea). Hyperketonemia in primiparous and multiparous cows led to increased adverse health events (culling rate, retained fetal membranes, puerperal metritis, clinical ketosis, left displaced abomasum) relative to Norm cows. Multiparous cows with HKHG had fewer metabolic disturbances (hypomagnesemia, hypocalcemia, elevated NEFA) than HK cows. Cows with HKHG had an increased incidence of clinical ketosis and left displaced abomasum relative to Norm cows. Cows with HG had similar metabolic profiles to Norm cows and had lower incidence of retained fetal membranes and puerperal metritis than cows with HK. Multiparous cows with HG produced more milk than Norm cows from wk 10 to 20, whereas multiparous cows with HK produced less milk than Norm cows. For primiparous cows, HK did not have a negative effect on milk production compared with Norm cows.
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Doenças dos Bovinos , Hipocalcemia , Hipoglicemia , Cetose , Gastropatias , Feminino , Bovinos , Animais , Leite/química , Lactação , Ácido 3-Hidroxibutírico , Ácidos Graxos não Esterificados , Hipocalcemia/veterinária , Cálcio , Estudos Prospectivos , Magnésio/análise , Doenças dos Bovinos/epidemiologia , Cetose/veterinária , Período Pós-Parto , Hipoglicemia/veterinária , Gastropatias/veterinária , Metaboloma , Glucose/metabolismo , Ureia/metabolismo , Triglicerídeos/metabolismoRESUMO
The objective of this study was to characterize plasma concentrations of pregnancy-associated glycoprotein (PAG) and progesterone (P4) as predictors of twins and pregnancy loss in Holstein cows with high-risk pregnancies. High-risk pregnancy was characterized using transrectal ultrasonography 37 d after artificial insemination (AI) based on the following criteria: small embryo size <15 mm, n = 10), slow heartbeat (<60 beats per minute, n = 11), and extra-amniotic membrane (additional amniotic membrane, n = 3). A cohort of twins (n = 41) diagnosed at d 37 post-AI was also enrolled. Each high-risk and twin pregnancy cow was paired with a cow of the same parity carrying a normal singleton at d 37 post-AI (control, n = 65). Blood samples were collected to measure PAG and P4 at d 37, 44, and 51 post-AI. Statistical analysis was performed using ANOVA, logistic regression, and receiver operator characteristic (ROC) curve with JMP software (SAS Institute Inc., Cary, NC). Pregnancy loss at d 51 post-AI was greater in high-risk pregnancies than in controls and twins (control = 1.5%; high-risk = 87.5%; twins = 12.2%). Concentration of PAG at d 37 post-AI did not differ among groups (control = 5.3 ± 0.7; high-risk = 4.8 ± 1.2; twins = 4.0 ± 0.9 ng/mL). Concentration of P4 at d 37 post-AI was greater in twins than in high-risk pregnancies and control, and lesser in high-risk pregnancies than in controls (control = 7.0 ± 0.3; high-risk = 5.9 ± 0.4; twins = 8.4 ± 0.3 ng/mL). Regression and ROC analysis for PAG at d 37 post-AI did not find a threshold to predict pregnancy loss or twins. Regression and ROC analysis for P4 at d 37 post-AI found that a threshold of 6.5 ng/mL predicted pregnancy loss with an area under the curve (AUC) of 0.64, and a threshold of 7.2 ng/mL predicted twins with AUC of 0.71. In summary, pregnancy loss and twins were predicted with only moderate accuracy by P4 concentration at d 37 post-AI, and the variability in PAG concentrations at d 37 post-AI was not sufficient to generate a threshold to predict pregnancy loss and twins in Holstein lactating cows.
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Sincronização do Estro , Progesterona , Animais , Bovinos , Feminino , Glicoproteínas , Hormônio Liberador de Gonadotropina , Inseminação Artificial/veterinária , Lactação , Gravidez , Gravidez de Alto RiscoRESUMO
BACKGROUND: Occupational skin diseases (OSD) have a high medical, social, economic and political impact. Knowledge dissemination from research activities to key stakeholders involved in health care is a prerequisite to make prevention effective. OBJECTIVES: To study and prioritize different activity fields and stakeholders that are involved in the prevention of OSD, to reflect on their inter-relationships, to develop a strategic approach for knowledge dissemination and to develop a hands-on tool for OSD prevention projects METHODS: Seven different activity fields that are relevant in the prevention of OSD have been stepwise identified. This was followed by an impact analysis. Fifty-five international OSD experts rated the impact and the influence of the activity fields for the prevention of OSD with a standardized questionnaire. RESULTS: Activity fields identified to have a high impact in OSD prevention are the political system, mass media and industry. The political system has a strong but more indirect effect on the general population via the educational system, local public health services or the industry. The educational system, mass media, industry and local public health services have a strong direct impact on the OSD 'at risk' worker. Finally, a hands-on tool for future OSD prevention projects has been developed that addresses knowledge dissemination and different stakeholder needs. CONCLUSION: Systematic knowledge dissemination is important to make OSD prevention more effective and to close the gap between research and practice. This study provides guidance to identify stakeholders, strategies and dissemination channels for systematic knowledge dissemination which need to be adapted to country-specific structures, for example the social security system and healthcare systems. A key for successful knowledge dissemination is building linkages among different stakeholders, building strategic partnerships and gaining their support right from the inception phase of a project.
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Promoção da Saúde/métodos , Disseminação de Informação/métodos , Doenças Profissionais/prevenção & controle , Dermatopatias/prevenção & controle , Humanos , Pesquisa Interdisciplinar , Meios de Comunicação de Massa , Inquéritos e Questionários , Pesquisa Translacional BiomédicaRESUMO
BACKGROUND: Docetaxel is a widely used cytotoxic agent. This study evaluates the impact of docetaxel toxicities on patient's health-related quality of life (QoL). PATIENTS AND METHODS: We conducted a multicenter, prospective, non-interventional trial, in which the QoL was assessed using the EORTC QLQ-C30 questionnaires at baseline and every 4 weeks up to 40 weeks in patients receiving a docetaxel-based chemotherapy for metastatic disease. Treatment-related adverse events were correlated with the corresponding QoL scores. Uni- and multivariate analyses were applied. RESULTS: From January 2008 to June 2011, a total of 2659 patients were included. The majority of patients (48.1%) had prostate cancer, followed by breast (17.1%) and non-small-cell-lung cancer (15.8%). Patients received a median of 5 docetaxel cycles with the median dose of 75 mg/m(2). The presence of grade 3/4 diarrhea showed the strongest effect on global health status/QoL average scores (50.91 versus 33.06), followed by vomiting (50.91 versus 35.17), dyspnea (50.94 versus 35.81), mucositis/stomatitis (50.88 versus 36.41), nausea (50.91 versus 36.68), infection (50.90 versus 37.14), fatigue (50.90 versus 43.82) and anemia (50.91 versus 41.03), P < 0.05 for all comparisons. Grade 3/4 leukopenia/neutropenia, alopecia, constipation, neurotoxicity and nail disorders had no significant impact on the global health status/QoL or other items. CONCLUSION: In this large non-interventional trial, docetaxel-associated grade 3 or 4 toxicities were shown to have a strong detrimental effect on patient's QoL. Notably, diarrhea and vomiting had the strongest negative impact on QoL measures. This has to be kept in mind while making therapeutic decisions and providing optimized supportive treatment measures. CLINICAL TRIALS NUMBER: This study was registered at Deutsches Krebsstudienregister (DKSR, primary registry in the WHO Registry Network) with the ID 527.
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Antineoplásicos/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/psicologia , Neoplasias/tratamento farmacológico , Qualidade de Vida , Taxoides/efeitos adversos , Idoso , Diarreia/induzido quimicamente , Diarreia/psicologia , Docetaxel , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Feminino , Alemanha , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Neoplasias/patologia , Neoplasias/psicologia , Seleção de Pacientes , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Vômito/induzido quimicamente , Vômito/psicologiaRESUMO
Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) µs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) µs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.
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The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-µs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."
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The objective of this study was to evaluate the performance of a small footprint benchtop somatic cell counter based on image cytometry (LactiCyte HD; Page and Pedersen International Ltd., Hopkinton, MA) against a flow cytometer employed at a regional dairy herd improvement (DHI) laboratory. Milk samples collected during monthly DHI testing were split into 2 samples. One sample was evaluated using flow cytometry (Bentley SomaCount FCM; Bentley Instruments, Chaska, MN) at the regional DHI laboratory, whereas the other was evaluated using image cytometry at 2 different image levels (full number of images, 16 pictures per slide; half number of images, 8 pictures per slide). Mean bias of the image cytometer at 16 images was -15,500 cells/mL, whereas at 8 images the bias was 21,800 cells/mL. When considering only cell counts ≤400,000 cells per mL, the bias for both imaging resolutions was positive, meaning the image cytometer read higher than the flow cytometer. Both imaging resolutions (16 and 8) had a concordance correlation coefficient greater than 0.95. Considering ≥200,000 cells/mL to be indicative of subclinical mammary gland infection, the sensitivity and specificity of the image cytometer at 16 images were 92.0% and 91.7%, whereas the sensitivity and specificity of the analyzer at 8 images were 92.0% and 85.7%, respectively. Method precision (repeatability; coefficients of variation) were calculated at 3 different somatic cell counts (100,000, 200,000, and 400,000 cells/mL) where each sample was run repeatedly 12 times. When analyzed at the full number of images the coefficients of variation were 16.9%, 11.7%, and 10.9% for 100,000, 200,000, and 400,000 cells/mL, respectively. Analysis at half the number of images resulted in coefficients of variation of 18.9%, 24.8%, and 8.7% for 100,000, 200,000, and 400,000 cells/mL. We conclude that the image cytometer is an acceptable somatic cell count analyzer for on-farm use for applications such as screening cows for microbiological testing, and that precision is superior when the analysis is performed at the full number of images allowed by the instrument.
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Flerovium (Fl, element 114) is the heaviest element chemically studied so far. To date, its interaction with gold was investigated in two gas-solid chromatography experiments, which reported two different types of interaction, however, each based on the level of a few registered atoms only. Whereas noble-gas-like properties were suggested from the first experiment, the second one pointed at a volatile-metal-like character. Here, we present further experimental data on adsorption studies of Fl on silicon oxide and gold surfaces, accounting for the inhomogeneous nature of the surface, as it was used in the experiment and analyzed as part of the reported studies. We confirm that Fl is highly volatile and the least reactive member of group 14. Our experimental observations suggest that Fl exhibits lower reactivity towards Au than the volatile metal Hg, but higher reactivity than the noble gas Rn.
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Nihonium (Nh, element 113) and flerovium (Fl, element 114) are the first superheavy elements in which the 7p shell is occupied. High volatility and inertness were predicted for Fl due to the strong relativistic stabilization of the closed 7p 1/2 sub-shell, which originates from a large spin-orbit splitting between the 7p 1/2 and 7p 3/2 orbitals. One unpaired electron in the outermost 7p 1/2 sub-shell in Nh is expected to give rise to a higher chemical reactivity. Theoretical predictions of Nh reactivity are discussed, along with results of the first experimental attempts to study Nh chemistry in the gas phase. The experimental observations verify a higher chemical reactivity of Nh atoms compared to its neighbor Fl and call for the development of advanced setups. First tests of a newly developed detection device miniCOMPACT with highly reactive Fr isotopes assure that effective chemical studies of Nh are within reach.
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The fusion-evaporation reaction 244Pu(48Ca,3-4n){288,289}114 was studied at the new gas-filled recoil separator TASCA. Thirteen correlated decay chains were observed and assigned to the production and decay of {288,289}114. At a compound nucleus excitation energy of E{*}=39.8-43.9 MeV, the 4n evaporation channel cross section was 9.8{-3.1}{+3.9} pb. At E^{*}=36.1-39.5 MeV, that of the 3n evaporation channel was 8.0{-4.5}{+7.4} pb. In one of the 3n evaporation channel decay chains, a previously unobserved α branch in 281Ds was observed (probability to be of random origin from background: 0.1%). This α decay populated the new nucleus 277Hs, which decayed by spontaneous fission after a lifetime of 4.5 ms.
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AIMS: Development of a predictive model for the determination of the shelf life of modified atmosphere-packed (MAP) cooked sliced ham in each step of the cold chain. METHODS AND RESULTS: The growth of lactic acid bacteria (LAB), as well as the development of the total viable count and changes of sensory and pH value parameters in MAP cooked sliced ham, stored under different constant temperature conditions from 2 to 15 degrees C was investigated. As a result of the measurements, the end of the shelf life could be considered as the time when LAB reach more than 7 log(10) CFU g(-1). Different primary and secondary models were tested and analysed to find the best way to calculate the shelf life. For primary modelling, the modified Gompertz Function and the modified Logistic Function were compared. There was no substantial difference between either model. The effect of temperature on the growth rate was modelled by using the Arrhenius and the Square root model, whereas the Arrhenius equation gave a better result. A combination of the primary and secondary model was used for shelf-life prediction under dynamic conditions. This combination showed the best prediction of microbial counts using the modified Logistic model and the Arrhenius equation. CONCLUSIONS: With the developed model, it is possible to predict the shelf life of MAP cooked sliced ham based on the growth of LAB under different temperature conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed model can be used to calculate the remaining shelf life in different steps of the chain. Thus, it can deliver an important contribution to improve food quality by optimizing the storage management.
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Manipulação de Alimentos , Microbiologia de Alimentos , Lactobacillaceae/crescimento & desenvolvimento , Modelos Biológicos , Temperatura Baixa , Concentração de Íons de Hidrogênio , Modelos LogísticosRESUMO
In a genome-wide screen using differential methylation hybridization (DMH), we have identified a CpG island within the 5' region and untranslated first exon of the secretory granule neuroendocrine protein 1 gene (SGNE1/7B2) that showed hypermethylation in medulloblastomas compared to fetal cerebellum. Bisulfite sequencing and combined bisulfite restriction assay were performed to confirm the methylation status of this CpG island in primary medulloblastomas and medulloblastoma cell lines. Hypermethylation was detected in 16/23 (70%) biopsies and 7/8 (87%) medulloblastoma cell lines, but not in non-neoplastic fetal (n=8) cerebellum. Expression of SGNE1 was investigated by semi-quantitative competitive reverse transcription-polymerase chain reaction and found to be significantly downregulated or absent in all, but one primary medulloblastomas and all cell lines compared to fetal cerebellum. After treatment of medulloblastoma cell lines with 5-aza-2'-deoxycytidine, transcription of SGNE1 was restored. No mutation was found in the coding region of SGNE1 by single-strand conformation polymorphism analysis. Reintroduction of SGNE1 into the medulloblastoma cell line D283Med led to a significant growth suppression and reduced colony formation. In summary, we have identified SGNE1 as a novel epigenetically silenced gene in medulloblastomas. Its frequent inactivation, as well as its inhibitory effect on tumor cell proliferation and focus formation strongly argues for a significant role in medulloblastoma development.
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Neoplasias Cerebelares/patologia , Metilação de DNA , Meduloblastoma/patologia , Proteína Secretora Neuroendócrina 7B2/genética , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Cerebelares/genética , Ilhas de CpG/genética , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Inibidores Enzimáticos/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Meduloblastoma/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Transcrição Gênica/efeitos dos fármacosRESUMO
The in vitro fidelity of reverse transcriptase from human immunodeficiency virus type I (HIV-1 RT) upon copying an RNA template was measured using the phi Xam 16 reversion assay. A phi X174 sequence harboring the amber 16 codon was cloned into a transcription vector. RNA obtained from transcription by bacteriophage T7 RNA polymerase was used as a template for RNA-directed DNA synthesis by HIV-1 RT. An imbalance of dNTP concentrations during the reverse transcription step served to distinguish between errors that arose from the transcription step and errors from reverse transcription. The frequency of dGTP.U mismatches was determined to be 1/360, while dGTP.rA mismatches formed at a rate of 1/4600. These are 20-fold and sevenfold higher, respectively, than the error rates determined for the same sequence with a DNA template. Due to a high background of errors in the RNA template originating from the transcription step only upper limits for the frequency of three other mismatches can be given. The data indicate that the reverse transcription step of the HIV-1 replication cycle contributes significantly to the generation of mutant viruses.
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HIV-1/enzimologia , DNA Polimerase Dirigida por RNA/metabolismo , RNA/metabolismo , Sequência de Bases , DNA/metabolismo , Dados de Sequência Molecular , Moldes GenéticosRESUMO
Many microorganisms in nature have evolved new genes which encode catabolic enzymes specific for chlorinated aromatic substrates, allowing them to utilize these compounds as sole sources of carbon and energy. An understanding of the evolutionary mechanisms involved in the acquisition of such genes may facilitate the development of microorganisms with enhanced capabilities of degrading highly chlorinated recalcitrant compounds. A number of studies have been based on microorganisms isolated from the environment which utilize simple chlorinated substrates. In our laboratory, a selective technique was used to isolate microorganisms capable of degrading highly chlorinated compounds, such as 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), as sole sources of carbon and energy. This article summarizes the genetic and biochemical information obtained regarding the pathway of degradation, the mechanism of recruitment of new genes, and the organization of the degradative genes. In addition, we discuss the potential practical application of such microorganisms in the environment.
Assuntos
Ácido 2,4,5-Triclorofenoxiacético/metabolismo , Burkholderia cepacia/enzimologia , Burkholderia cepacia/genética , Dioxigenases , Genes Bacterianos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Biodegradação Ambiental , Burkholderia cepacia/crescimento & desenvolvimento , Genoma Bacteriano , Família Multigênica , Oxirredutases/genética , Oxirredutases/metabolismo , Oxigenases/genética , Oxigenases/metabolismoRESUMO
OBJECTIVE: To analyze treatment outcomes and the association between treatment effects and health-related quality of life (HRQoL) for incontinent children, and their parents. SUBJECTS AND METHODS: Health-related quality of life in 70 consecutively treated children, and their parents, was assessed with the Pediatric Incontinence Questionnaire and the WHO-Quality-Of-Life-BREF questionnaire. This was assessed before and after three months of standardized treatment. RESULTS: In 44.3% of children, symptoms decreased by 50-89%. After three months of treatment, the HRQoL of children improved significantly. Children with bladder and bowel dysfunction had a significantly lower HRQoL than children with isolated nocturnal enuresis, daytime urinary incontinence or fecal incontinence. Parental HRQoL did not change significantly within three months of treatment. Parents showed a significantly lower mean in the 'psychological' domain of the WHO-QoL-BREF questionnaire compared to norms. CONCLUSION: Children with different subtypes of incontinence can be treated effectively within three months of therapy. After three months, significant improvements of HRQoL were shown. Parents showed no general reduction in their quality of life (QoL). Specific aspects of parental QoL were impaired, but did not improve during the treatment of their children.