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2.
Rapid Commun Mass Spectrom ; 30(24): 2594-2600, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-27709696

RESUMO

RATIONALE: Extraction of lipids from tissues prior to carbon stable isotope analysis (SIA) has become a common practice, despite a lack of species-specific data to indicate when lipid extraction is needed. Marine invertebrates, including bivalves, are known to store carbon as glycogen and less in the form of lipids than other species, potentially reducing the need for lipid extraction even when C:N values are above 3.5, a value that previous studies suggest indicates a need for lipid extraction of animal tissues. METHODS: We investigated the need for lipid extraction on individual tissues (adductor muscle, gut gland, gill) and whole tissue of a glycogen-storing species, the oyster Crassostrea virginica. Bulk and lipid-extracted samples were analyzed for their C and N stable isotope ratios by continuous flow isotope ratio mass spectrometry (IRMS). Samples were analyzed on a 20-20 isotope ratio mass spectrometer (PDZ Europa) after combustion in an elemental analyzer (PDZ Europa Automatic Analyzer-Gas Solid Liquid). RESULTS: Although the C:N values for most bulk (unextracted) tissue samples were greater than 3.5, the lipid-extracted δ13 C values did not differ from the bulk values. Lipid extraction, however, affected δ15 N values in all tissue types except adductor muscle, indicating that separate SIA may be required when tissues are lipid extracted. CONCLUSIONS: These data demonstrate that it is not necessary to lipid extract oyster tissues in all cases, and that C:N thresholds for lipid extraction in other species may not be reliable for organisms such as oysters that store glycogen. Our data indicate that minimizing unnecessary lipid extraction through preliminary testing will save researchers time and expense by avoiding superfluous sample handling, reducing concern over secondary effects on data quality, and reducing the costs of reagents and additional separate stable isotope analysis to ensure analytical accuracy. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Isótopos de Carbono/análise , Glicogênio/análise , Lipídeos/química , Isótopos de Nitrogênio/análise , Ostreidae/química , Frutos do Mar/análise , Animais , Lipídeos/isolamento & purificação , Espectrometria de Massas
3.
Br Dent J ; 220(12): 623-5, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27338901

RESUMO

A patient was referred by a clinical oncologist regarding a non-healing area of bone in the lower jaw. The patient was taking denosumab (Prolia(®), Xgeva(®)) when they had a tooth extracted and the area failed to heal. Following suspension of the drug, the area healed with mucosal coverage. This new class of drugs are being increasingly used as an alternative antiresorptive drug to bisphosphonates and are licenced in the UK for prevention of osteoporotic fractures and prevention of skeletal-related events (SREs) in patients with metastatic cancer.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea/efeitos adversos , Denosumab/efeitos adversos , Idoso , Difosfonatos , Humanos , Arcada Osseodentária , Neoplasias , Extração Dentária
4.
Clin Exp Immunol ; 176(1): 1-10, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24313320

RESUMO

Protein kinases mediate protein phosphorylation, which is a fundamental component of cell signalling, with crucial roles in most signal transduction cascades: from controlling cell growth and proliferation to the initiation and regulation of immunological responses. Aberrant kinase activity is implicated in an increasing number of diseases, with more than 400 human diseases now linked either directly or indirectly to protein kinases. Protein kinases are therefore regarded as highly important drug targets, and are the subject of intensive research activity. The success of small molecule kinase inhibitors in the treatment of cancer, coupled with a greater understanding of inflammatory signalling cascades, has led to kinase inhibitors taking centre stage in the pursuit for new anti-inflammatory agents for the treatment of immune-mediated diseases. Herein we discuss the main classes of kinase inhibitors; namely Janus kinase (JAK), mitogen-activated protein kinase (MAPK) and spleen tyrosine kinase (Syk) inhibitors. We provide a mechanistic insight into how these inhibitors interfere with kinase signalling pathways and discuss the clinical successes and failures in the implementation of kinase-directed therapeutics in the context of inflammatory and autoimmune disorders.


Assuntos
Anti-Inflamatórios/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Doenças Autoimunes/enzimologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo , Modelos Biológicos , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Quinase Syk , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Clin Neurophysiol ; 124(4): 708-12, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23085391

RESUMO

OBJECTIVE: Stimulation intensity (SI) in transcranial magnetic stimulation is commonly set in relation to motor threshold (MT), or to achieve a motor-evoked potential (MEP) of predefined amplitude (usually 1 mV). Recently, IFCN recommended adaptive threshold-hunting over the previously endorsed relative-frequency method. We compared the Rossini-Rothwell (R-R) relative-frequency method to an adaptive threshold-hunting method based on parameter estimation by sequential testing (PEST) for determining MT and the SI to target a MEP amplitude of 1 mV (I(1) mV). METHODS: In 10 healthy controls we determined MT and I(1) mV with R-R and PEST using a blinded crossover design, and performed within-session serial PEST measurements of MT. RESULTS: There was no significant difference between methods for MT (52.6±2.6% vs. 53.7±3.1%; p=0.302; % maximum stimulator output; R-R vs. PEST, respectively) or I(1) mV (66.7±3.0% vs. 68.8±3.8%; p=0.146). There was strong correlation between R-R and PEST estimates for both MT and I(1) mV. R-R required significantly more stimuli than PEST. Serial measurements of MT with PEST were reproducible. CONCLUSIONS: PEST has the advantage of speed without sacrificing precision when compared to the R-R method, and is adaptable to other SI targets. SIGNIFICANCE: Our results in healthy controls add to increasing evidence in favour of adaptive threshold-hunting methods for determining SI.


Assuntos
Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Estudos Cross-Over , Interpretação Estatística de Dados , Eletromiografia , Feminino , Humanos , Masculino , Córtex Motor/fisiologia , Adulto Jovem
7.
Br Dent J ; 206(9): E19; discussion 478-9, 2009 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-19360024

RESUMO

OBJECTIVE: To assess the treatment needs of patients undergoing pre-haematopoietic stem cell transplant (HSCT) dental assessment, to collate the examination findings and treatment provided and to define the management issues impacting on care. DESIGN: Single centre retrospective analysis. SETTING: Salaried Primary Care Dental Service, Western General Hospital, Edinburgh, UK. SUBJECTS AND METHODS: One hundred and sixteen available charts of patients who attended for pre-transplant dental assessment during April 2004-June 2007 were examined. RESULTS: Ninety-four patients, 52 men (55.3%) and 42 women (43.6%), were included. Patients were referred a mean of 31.5 (SD 18.82) days before admission for transplant. Dental assessment occurred, on average, 7.88 days (SD 6.78) following referral. Eighty-eight (93.6%) patients were dentate, while six (6.3%) were edentulous. Eighty-eight (93.6%) patients presented with oral disease; 89 (94.7%) patients received dental care. Issues impacting on care were medical (n = 88, 93.6%), time constraints (n = 73, 77.7%), no GDP (n = 25, 26.7%), dental complexity (n = 5, 5.3%) and anxiety management (n = 1, 1.1%). CONCLUSION: The majority of patients required dental care, most of which, for healthy adults, would normally be completed within a primary care setting. However, the issues surrounding the care of patients destined for HSCT indicate that there is a place for a dedicated dental service as part of the multidisciplinary team.


Assuntos
Assistência Odontológica para Doentes Crônicos , Acessibilidade aos Serviços de Saúde , Transplante de Células-Tronco Hematopoéticas , Avaliação das Necessidades , Adolescente , Adulto , Idoso , Ansiedade/complicações , Auditoria Odontológica , Cálculos Dentários/complicações , Cárie Dentária/complicações , Profilaxia Dentária , Restauração Dentária Permanente , Unidade Hospitalar de Odontologia , Feminino , Neoplasias Hematológicas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Boca Edêntula/complicações , Higiene Bucal , Doenças Periodontais/complicações , Cuidados Pré-Operatórios , Encaminhamento e Consulta , Estudos Retrospectivos , Fatores de Tempo , Extração Dentária , Adulto Jovem
8.
Phytopathology ; 98(8): 860-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18943203

RESUMO

ABSTRACT Sources of inoculum were investigated for dominant hosts of Phytophthora ramorum in a redwood forest. Infected trunks, twigs, and/or leaves of bay laurel (Umbellularia californica), tanoak (Lithocarpus densiflorus), and redwood (Sequoia sempervirens) were tested in the laboratory for sporangia production. Sporangia occurred on all plant tissues with the highest percentage on bay laurel leaves and tanoak twigs. To further compare these two species, field measurements of inoculum production and infection were conducted during the rainy seasons of 2003-04 and 2004-05. Inoculum levels in throughfall rainwater and from individual infections were significantly higher for bay laurel as opposed to tanoak for both seasons. Both measurements of inoculum production from bay laurel were significantly greater during 2004-05 when rainfall extended longer into the spring, while inoculum quantities for tanoak were not significantly different between the 2 years. Tanoak twigs were more likely to be infected than bay laurel leaves in 2003-04, and equally likely to be infected in 2004-05. These results indicate that the majority of P. ramorum inoculum in redwood forest is produced from infections on bay laurel leaves. Years with extended rains pose an elevated risk for tanoak because inoculum levels are higher and infectious periods continue into late spring.


Assuntos
Phytophthora/isolamento & purificação , Sequoia/microbiologia , Árvores/microbiologia , Doenças das Plantas/microbiologia , Chuva/microbiologia , Estações do Ano , Fatores de Tempo
9.
J Anim Sci ; 86(7): 1697-708, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18344307

RESUMO

Dried distillers grains plus solubles (DDGS) contain fat and rumen undegradable intake protein, both of which have been shown to increase reproductive performance in heifers. The mechanisms leading to enhanced reproduction have not been fully defined. The objectives of this research were to evaluate effects of DDGS in late gestation heifer diets on animal and reproductive performance and on blood plasma concentrations of GH, IGF-I, and NEFA. Over 2 yr, 201 heifers were randomly allotted to 1 of 2 diets, which were similar in energy and adequate in rumen degradable intake protein and were fed from d 190 of gestation through calving. Diets were grass hay with DDGS or soybean hulls (SBH) and a supplement. Cow BW and BCS were measured from the beginning of treatment through weaning. Blood samples were collected prepartum on d 71 and 69 of the feeding period and weekly after calving for 4 and 6 wk (d 84 to 105 and d 76 to 111 relative to the feeding period) during yr 1 and 2, respectively. No treatment x year interactions were detected for any of the performance, hormonal, or reproductive dependent variables. Both treatments caused positive BW changes over the feeding period, but DDGS heifers had a greater (P < 0.01) positive BW change compared with SBH heifers. Initial and final BCS and BCS change were similar (P >/= 0.26) between DDGS and SBH treatments. Treatment did not influence (P >/= 0.12) BW or BCS change during the postpartum period. Calving ease, calf vigor, and calf birth weight, weaning weight, and ADG (birth to weaning) were similar (P >/= 0.41) between treatments. The proportion of cows that had initiated estrous cycles (P = 0.46) and the pregnancy distribution (P >/= 0.21) were similar between treatments. However, a greater (P = 0.058) percentage of DDGS cows became pregnant compared with SBH cows (94 and 84%). In both years, there were no effects of treatment (P >/= 0.17) or treatment x time (P >/= 0.52), but time influenced (P 0.10) for the duration of the sampling period. Concentrations of NEFA increased from calving through d 8 and gradually declined through d 20. Prepartum diets containing DDGS, a source of fat and UIP, benefited pregnancy rates in well-maintained, primiparous beef heifers.


Assuntos
Bovinos/fisiologia , Ciclo Estral/fisiologia , Glycine max , Reprodução/fisiologia , Zea mays , Ração Animal , Animais , Animais Recém-Nascidos , Peso ao Nascer/fisiologia , Peso Corporal/fisiologia , Bovinos/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Gravidez , Progesterona/sangue , Distribuição Aleatória , Fatores de Tempo
10.
Eur Respir J ; 31(6): 1292-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18256068

RESUMO

The extent of respiratory dysfunction is not well characterised in children with neonatal chronic lung disease (nCLD) too young to perform spirometry. Forced oscillations are easily performed by healthy young children; however, they may be more difficult for those with nCLD. The present study aimed to describe the feasibility of using the forced oscillation technique in children with nCLD in a routine clinical setting and to investigate the influence of neonatal factors on subsequent lung function. Respiratory function tests were attempted in 64 patients with nCLD aged 3.2-6.6 yrs. Respiratory resistance and reactance at 6, 8 and 10 Hz were expressed as z-scores derived from a healthy reference population. The within-test variation and between-test repeatability were also assessed. Technically, satisfactory data were obtained from 77% of children. On grouped data, z-scores for all oscillatory indices were different from zero and related to hospital oxygen administration in the neonatal period. In conclusion, the forced oscillation technique was feasible in preschool children with neonatal chronic lung disease in the clinical outpatient setting. These children had lung function significantly worse than that predicted from healthy children. Respiratory function assessed using forced oscillations appeared to reflect the severity of lung disease during the neonatal period.


Assuntos
Resistência das Vias Respiratórias , Doenças do Recém-Nascido/fisiopatologia , Pneumopatias/fisiopatologia , Oscilometria/métodos , Estudos de Casos e Controles , Criança , Pré-Escolar , Doença Crônica , Estudos de Viabilidade , Feminino , Humanos , Recém-Nascido , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
11.
Vet Rec ; 161(19): 647-52, 2007 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17993655

RESUMO

In 2006 there was an outbreak of equine infectious anaemia (EIA) in Ireland. This paper describes the use of the diagnosis of clinical and subclinical cases of the disease. In acute cases the ELISAs and the immunoblot were more sensitive than the AGID. In one mare, fluctuating antibody levels were observed in all the serological assays before it seroconverted by AGID. Viral RNA and DNA were detected by RT-PCR and PCR in all the tissues from the infected animals examined postmortem. The PCR detected viral DNA in plasma regardless of the stage of the disease. In contrast, the RT-PCR detected RNA in only 52 per cent of the seropositive animals tested and appeared to be most sensitive for the detection of virus early in infection. Both PCR and RT-PCR demonstrated potential to detect acutely infected horses earlier than some of the official tests. The serological data suggest that the usual incubation/seroconversion period for this strain of the virus was approximately 37 days but may be more than 60 days in a few cases.


Assuntos
Anticorpos Antivirais/sangue , Surtos de Doenças/veterinária , Anemia Infecciosa Equina/diagnóstico , Anemia Infecciosa Equina/epidemiologia , Vírus da Anemia Infecciosa Equina/imunologia , Animais , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Cavalos , Immunoblotting/métodos , Immunoblotting/veterinária , Vírus da Anemia Infecciosa Equina/isolamento & purificação , Irlanda/epidemiologia , Masculino , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sensibilidade e Especificidade , Fatores de Tempo
12.
Eur Respir J ; 30(5): 892-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17690128

RESUMO

Measurement of lung function is an important component of clinical management in cystic fibrosis (CF), but has been difficult in young children. The present study aimed to characterise the utility of the forced oscillation technique for measurement of lung function in preschool-aged children with CF in a routine clinical setting. Lung function was assessed in 56 young children (aged 2-7 yrs) with CF. Respiratory system resistance (R(rs)) and reactance (X(rs)) at 6, 8 and 10 Hz were measured and expressed as Z-scores. Children were classified as asymptomatic or symptomatic based on an administered respiratory questionnaire and physical examination at the time of testing. Between-test repeatability was assessed in 25 children. Measurement of lung function using the forced oscillation technique was feasible in the CF clinic. The children with CF, as a group, had Z-scores for R(rs) at 6 Hz (R(rs,6)) R(rs,8), R(rs,10), X(rs) at 6 Hz (X(rs,6)) and X(rs,8) that were significantly different from zero. Children with current symptoms showed significantly decreased X(rs) and increased R(rs,6) compared with asymptomatic children. Measurement of lung function using the forced oscillation technique is feasible in young children with cystic fibrosis in a clinical setting. The technique has the potential to improve knowledge concerning early cystic fibrosis lung disease.


Assuntos
Resistência das Vias Respiratórias , Fibrose Cística/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Oscilometria/métodos , Exame Físico , Reprodutibilidade dos Testes , Testes de Função Respiratória/métodos , Estatísticas não Paramétricas , Inquéritos e Questionários
13.
Insect Mol Biol ; 16(4): 469-79, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17651236

RESUMO

Ixodes ticks are vectors of several pathogens including Borrelia burgdorferi. Tick saliva contains numerous molecules that facilitate blood feeding without host immune recognition and rejection. We have expressed, purified, and characterized Ixodes scapularis salivary protein 20 (Salp20), a potential inhibitor of the alternative complement pathway that shares homology with the Isac protein family. When analysed by SDS-PAGE and size exclusion chromatography, Salp20 was approximately 48 kDa, more than double its predicted mass, primarily due N- and O-linked glycosylations. Recombinant Salp20 inhibited the alternative complement pathway by dissociating the C3 convertase, and partially protected a serum sensitive species of Borrelia from lysis by normal human serum. We propose that Salp20 facilitates tick feeding and possibly protects tick-borne pathogens from complement components.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Ixodes/genética , Ixodes/metabolismo , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/farmacologia , Sequência de Aminoácidos , Animais , Borrelia , Dados de Sequência Molecular , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/metabolismo
14.
J Anim Sci ; 82 E-Suppl: E83-92, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15471818

RESUMO

Designing a sound cow-calf nutritional program requires knowledge of nutrient requirements, diet quality, and intake. Effectively using the NRC (1996) beef cattle requirements model (1996NRC) also requires knowledge of dietary degradable intake protein (DIP) and microbial efficiency. Objectives of this paper are to 1) describe a framework in which 1996NRC-applicable data can be generated, 2) describe seasonal changes in nutrients on native range, 3) use the 1996NRC to predict nutrient balance for cattle grazing these forages, and 4) make recommendations for using the 1996NRC for forage-fed cattle. Extrusa samples were collected over 2 yr on native upland range and subirrigated meadow in the Nebraska Sandhills. Samples were analyzed for CP, in vitro OM digestibility (IVOMD), and DIP. Regression equations to predict nutrients were developed from these data. The 1996NRC was used to predict nutrient balances based on the dietary nutrient analyses. Recommendations for model users were also developed. On subirrigated meadow, CP and IVOMD increased rapidly during March and April. On native range, CP and IVOMD increased from April through June but decreased rapidly from August through September. Degradable intake protein (DM basis) followed trends similar to CP for both native range and subirrigated meadow. Predicted nutrient balances for spring- and summer-calving cows agreed with reported values in the literature, provided that IVOMD values were converted to DE before use in the model (1.07 x IVOMD - 8.13). When the IVOMD-to-DE conversion was not used, the model gave unrealistically high NE(m) balances. To effectively use the 1996NRC to estimate protein requirements, users should focus on three key estimates: DIP, microbial efficiency, and TDN intake. Consequently, efforts should be focused on adequately describing seasonal changes in forage nutrient content. In order to increase use of the 1996NRC, research is needed in the following areas: 1) cost-effective and accurate commercial laboratory procedures to estimate DIP, 2) reliable estimates or indicators of microbial efficiency for various forage types and qualities, 3) improved estimates of dietary TDN for forage-based diets, 4) validation work to improve estimates of DIP and MP requirements, and 5) incorporation of nitrogen recycling estimates.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Modelos Biológicos , Necessidades Nutricionais , Animais , Clima , Dieta/normas , Dieta/veterinária , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/metabolismo , Feminino , Lactação/fisiologia , Poaceae/química , Poaceae/crescimento & desenvolvimento , Gravidez , Análise de Regressão , Estações do Ano
15.
Emerg Med J ; 21(3): 302-5, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15107367

RESUMO

OBJECTIVES: Some trauma patients have an undiagnosed cervical spine injury but require immediate airway control. This paper reports an emergency department's (ED) experience with these patients. In particular, is there a worse neurological outcome? METHODS: A retrospective study over 6.5 years, based on prospectively collected data from the Royal Perth Hospital trauma registry. Patients with a cervical spine injury were identified and clinical data were abstracted. The primary outcome measure was evidence of exacerbation of cervical spine injury as a result of intubation by ED medical staff. RESULTS: 308 patients (1.9%) of the 15 747 trauma patients were intubated by ED medical staff. Thirty seven (12%) were subsequently verified to have a cervical spine injury, of which 36 were managed with orotracheal intubation. Twenty five (69%) survived to have a meaningful post-intubation neurological examination. Fourteen (56%) of these 25 patients had an unstable cervical spine injury. Ninety per cent of all ED intubations were by ED medical staff. No worsening of neurological outcomes occurred. CONCLUSIONS: Every ninth trauma patient that this ED intubates has a cervical spine injury. Intubation by ED medical staff did not worsen neurological outcome. In the controlled setting of an ED staffed by senior practitioners, patients with undiagnosed cervical spine injury can be safely intubated.


Assuntos
Vértebras Cervicais/lesões , Intubação Intratraqueal/efeitos adversos , Fraturas da Coluna Vertebral/complicações , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Traumatismos da Medula Espinal/etiologia , Fraturas da Coluna Vertebral/etiologia
16.
J Anim Sci ; 81(3): 563-70, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12661635

RESUMO

Metabolizable protein (MP) requirements of spring calving heifers increase over the winter due to advancing gestation. The MP content of grazed winter forage is low, which may result in an MP deficiency. The objective was to compare the response of supplementing pregnant yearling heifers to meet MP requirements versus conventional CP supplementation. In 1997-98 and in 1998-99, pregnant, March-calving heifers (2,120 animals; 358 kg) at two locations of a commercial ranch in the Nebraska Sandhills, were used following breeding through calving as 2-yr-olds (cows). Heifers were randomly allotted to one of two supplementation treatments (about 265 heifers/treatment) each year at each of two locations (Ashby and Whitman, NE). Treatments were 1) supplementation to meet MP requirements (MPR) or 2) supplementation to meet CP requirements (CPR). Heifers grazed upland range and meadow and were offered supplements three times weekly from mid-September to mid- or late-February. Increasing amounts of meadow hay were fed from mid-December through calving. After supplementation ended in February, heifers were managed in one group at each location until the following October. Body weights and body condition scores were taken in September, February, and October. Two-yr-old pregnancy rates were determined via rectal palpation in October. Capital budgeting techniques were used to determine the economic return of supplementation strategies. There were no differences in BW (P = 0.41) or body condition score (P = 0.99) change during the winter among treatment groups across years and locations, but MPR cows were heavier (425 kg) than CPR cows (421 kg) at the time of 2-yr-old pregnancy testing (P = 0.07). Pregnancy rate was higher (P = 0.001) in the MPR (91%) compared to the CPR treatment (86%). Regression analysis showed that the response of the MPR treatment on pregancy rates tended to be negatively correlated with precalving body condition score (P = 0.11), body condition score loss over the winter (P = 0.07), and body condition score at weaning of the first calf (P = 0.08). The improvement in 2-yr-old pregnancy by supplementing to meet MP requirements improved the value of each bred heifer by 13.64 dollars. We conclude that balancing MP requirements during gestation may result in a subsequent increase in 2-yr-old pregnancy and increase the value of young females.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Proteínas Alimentares/administração & dosagem , Prenhez/fisiologia , Animais , Constituição Corporal , Peso Corporal , Proteínas Alimentares/economia , Feminino , Nível de Saúde , Necessidades Nutricionais , Gravidez , Taxa de Gravidez , Distribuição Aleatória , Reprodução , Estações do Ano
17.
J Anim Sci ; 81(3): 800-11, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12661661

RESUMO

Three experiments were conducted to evaluate the response of supplementing primiparous heifers based on the metabolizable protein (MP) system during pregnancy and lactation. In Exp. 1, 12 pregnant, March-calving heifers (432 +/- 10 kg) grazing Sandhills range were randomly allotted to one of two treatments: supplementation based on either the MP system (MPR) or the CP system (CPR). Supplements were fed to individual heifers from October to February and no hay was offered. Grazed forage organic matter intake (FOMI) was measured in November, January, and February. In Exp. 2, 18 heifers (424 +/- 8 kg) were randomly allotted to one of three treatments: 1) supplementation based on the MP system with hay fed in January and February (average 2.0 kg/d; MPR/hay), 2) supplementation based on the CP system, with hay fed in January and February (CPR/hay), or 3) supplementation based on the MP system, with no hay fed (MPR/no hay). Supplements were fed from October to February, and FOMI was measured in December and February. In Exp. 3, lactating 2-yr-old cows (394 +/- 7 kg) maintained on meadow hay were supplemented to meet either 1) MP requirements (LMPR) or 2) degradable intake protein requirements (LDIPR). Body weight (BW) and body condition score change, hay intake, and milk production were measured. In Exp. 1, grazed FOMI decreased (P = 0.0001) from 1.9% of BW in November to 1.2% in February, but no differences among treatments were detected for FOMI or BW change. In Exp. 2, grazed FOMI declined (P = 0.0001) from 1.7% of BW in December to 1.1% in February, with no differences among treatments. Heifers on the MPR/hay and CPR/hay treatments had higher (P = 0.0018) total intake (grazed forage + hay intake) in February (1.7% BW) than the MPR/no hay heifers (1.1% BW). Heifers on the MPR/no hay treatment had a lower weight (P = 0.02) and tended (P = 0.11) to have a lower BCS than heifers on other treatments. In Exp. 3, the LMPR cows had higher (P = 0.02) ADG than LDIPR cows (0.41 and 0.14, respectively), but treatment did not affect milk production. Organic matter hay intake averaged 2.4% of BW. We conclude that supplementation to meet MP requirements had little benefit to heifer performance during gestation, but increased weight change during lactation. Because grazed forage intake decreased from 1.9 to 1.1% of BW with advancing gestation, supplemental energy is necessary to reduce weight and condition loss of gestating hefiers grazing dormant Sandhills range.


Assuntos
Constituição Corporal/fisiologia , Bovinos/fisiologia , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Lactação/fisiologia , Ração Animal , Animais , Peso Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Ingestão de Energia/fisiologia , Feminino , Nível de Saúde , Lactação/efeitos dos fármacos , Necessidades Nutricionais , Paridade , Gravidez , Distribuição Aleatória
19.
J Am Chem Soc ; 123(45): 11237-47, 2001 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-11697966

RESUMO

Solutions of K[Au(CN)(2)] and K[Ag(CN)(2)] in water and methanol exhibit strong photoluminescence. Aqueous solutions of K[Au(CN)(2)] at ambient temperature exhibit luminescence at concentration levels of > or =10(-2) M, while frozen methanol glasses (77 K) exhibit strong luminescence with concentrations as low as 10(-5) M. The corresponding concentration limits for K[Ag(CN)(2)] solutions are 10(-1) M at ambient temperature and 10(-4) M at 77 K. Systematic variations in concentration, solvent, temperature, and excitation wavelength tune the luminescence energy of both K[Au(CN)(2)] and K[Ag(CN)(2)] solutions by >15 x 10(3) cm(-1) in the UV-visible region. The luminescence bands have been individually assigned to *[Au(CN)(2)(-)](n) and *[Ag(CN)(2)(-)](n) excimers and exciplexes that differ in "n" and geometry. The luminescence of Au(I) compounds is related for the first time to Au-Au bonded excimers and exciplexes similar to those reported earlier for Ag(I) compounds. Fully optimized unrestricted open-shell MP2 calculations for the lowest-energy triplet excited state of staggered [Au(CN)(2)(-)](2) show the formation of a Au-Au sigma single bond (2.66 A) in the triplet excimer, compared to a weaker ground-state aurophilic bond (2.96 A). The corresponding frequency calculations revealed Au-Au Raman-active stretching frequencies at 89.8 and 165.7 cm(-1) associated with the ground state and lowest triplet excited state, respectively. The experimental evidence of the exciplex assignment includes the extremely large Stokes shifts and the structureless feature of the luminescence bands, which suggest very distorted excited states. Extended Hückel (EH) calculations for [M(CN)(2)(-)](n) and *[M(CN)(2)(-)](n) models (M = Au, Ag; n = 2, 3) indicate the formation of M-M bonds in the first excited electronic states. From the average EH values for staggered dimers and trimers, the excited-state Au-Au and Ag-Ag bond energies are predicted to be 104 and 112 kJ/mol, respectively. The corresponding bond energies in the ground state are 32 and 25 kJ/mol, respectively.

20.
Environ Pollut ; 113(2): 155-62, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11383333

RESUMO

Bioventing is an improved method of soil remediation that is being used with increasing frequency. In this paper, we refine techniques to measure the progress of petroleum hydrocarbon decomposition by monitoring vapor phase composition with synchronous scan fluorescence spectroscopy (SSFS). Analysis of the vapor phase has advantages compared to standard extraction techniques that require extensive sample handling and clean up. For comparison, hydrocarbon contamination in the soil was measured by analysis of Soxhlet extractions with gas chromatography-mass spectrometry (GC-MS). Comparison of the GC-MS and SSFS data showed that changes in hydrocarbon composition measured in the vapor phase provide an accurate measure of decomposition reactions taking place in the soil.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias Aeróbias/metabolismo , Poluição Ambiental/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Petróleo/metabolismo , Espectrometria de Fluorescência , Volatilização
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