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2.
J Dairy Sci ; 103(8): 7498-7508, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32448582

RESUMO

The objective of this experiment was to identify and characterize the bovine milk proteome within the skim milk fraction and milk fat globule membrane (MFGM)-associated fraction from 16 organically certified lactating Jersey cows after a short term of grazing pastures with or without annual forage crops (AFC). Cows were offered a partial mixed ration (∼60% of dry matter intake) and approximately 40% of their total dry matter intake as herbage. Eight cows were offered a cool-season grass-legume herbage (GLH), which included orchardgrass (Dactylis glomerata), timothy (Phleum pratense), Kentucky bluegrass (Poa pratensis), and white clover (Trifolium repens). The other 8 cows were offered the same GLH strip-tilled with the AFC, including oat (Avena sativa), millet (Pennisetum glaucum), teff (Eragrostis tef), buckwheat (Fagopyrum esculentum), and chickling vetch (Lathyrus sativus). Milk samples were collected from each cow during a.m. and p.m. milkings on d 19 to 21 of grazing, and composite milk samples per cow were analyzed for (1) the high-abundance milk protein profile, (2) the skim milk low-abundance protein-enriched proteome, and (3) the MFGM proteome. Of the 443 proteins identified in the skim and MFGM proteomes, 433 were included in statistical analysis, including 68 proteins identified in the skim milk fraction and 365 in the MFGM-associated fraction. Analysis of the skim and MFGM proteomes encompassed unique gene ontology profiles and proportions of functional classifications. In response to diet, αS1-casein as well as 8 low-abundance proteins were present in higher concentration or abundance in milk from cows grazing the GLH strip-tilled with the AFC compared with milk from cows grazing GLH, suggesting that even short-term grazing of pastures including some AFC may affect the milk proteome.


Assuntos
Ração Animal , Dieta/veterinária , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Herbivoria , Gotículas Lipídicas/metabolismo , Leite/química , Plantas Comestíveis , Proteoma/metabolismo , Ração Animal/análise , Animais , Biodiversidade , Bovinos , Fabaceae , Feminino , Lactação , Proteínas do Leite/análise , Plantas Comestíveis/classificação , Poaceae , Estações do Ano , Trifolium
3.
J Dairy Sci ; 100(11): 9392-9401, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918156

RESUMO

Heat treatment of colostrum is performed on modern dairy farms to reduce pathogenic contamination before hand-feeding the colostrum to newborn calves; however, limited data are available concerning effects of heat treatment on biologically active proteins in colostrum. The objective of this exploratory study was to investigate effects of heat treatment and length of heat treatment on colostrum protein profile. Colostrum samples were collected from Holstein cows within 12 h after parturition and assigned to the following groups: heat treatment at 60°C for 0 (untreated control), 30, 60, or 90 min. Samples were fractionated using acid precipitation, followed by ultracentrifugation and ProteoMiner (Bio-Rad Laboratories, Hercules, CA) treatment, and tandem-mass tagging was used to comparatively assess the low abundance protein profile. A total of 162 proteins were identified with more than 2 peptides in the low abundance protein enriched fraction. Of these, 62 differed in abundance by more than 2-fold in heat-treated samples compared with the unheated control. The majority of proteins affected by heat treatment were involved in immunity, enzyme function, and transport-related processes; affected proteins included lactadherin, chitinase-3-like protein 1, and complement component C9. These results provide a foundation for further research to determine optimum heat treatment practices to ensure newborn calves are fed colostrum-containing proteins with the highest nutritional and biological value.


Assuntos
Bovinos/fisiologia , Colostro/química , Temperatura Alta , Proteoma , Animais , Feminino , Imunoglobulina G , Gravidez
4.
J Dairy Sci ; 100(9): 7246-7261, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28711247

RESUMO

Little is known about the bovine milk proteome or whether it can be affected by diet. The objective of this study was to determine if the dietary rumen degradable protein (RDP):rumen undegradable protein (RUP) ratio could alter the bovine milk proteome. Six Holstein cows (parity: 2.5 ± 0.8) in mid lactation were blocked by days in milk (80 ± 43 d in milk) and milk yield (57.5 ± 6.0 kg) and randomly assigned to treatment groups. The experiment was conducted as a double-crossover design consisting of three 21-d periods. Within each period, treatment groups received diets with either (1) a high RDP:RUP ratio (RDP treatment: 62.4:37.6% of crude protein) or (2) a low RDP:RUP ratio (RUP treatment: 51.3:48.7% of crude protein). Both diets were isonitrogenous and isoenergetic (crude protein: 18.5%, net energy for lactation: 1.8 Mcal/kg of dry matter). To confirm N and energy status of cows, dry matter intake was determined daily, rumen fluid samples were collected for volatile fatty acid analysis, blood samples were collected for plasma glucose, ß-hydroxybutyrate, urea nitrogen, and fatty acid analysis, and total 24-h urine and fecal samples were collected for N analysis. Milk samples were collected to determine the general milk composition and the protein profile. Milk samples collected for high-abundance protein analysis were subjected to HPLC analysis to determine the content of α-casein, ß-casein, and κ-casein, as well as α-lactalbumin and ß-lactoglobulin. Samples collected for low-abundance protein analysis were fractionated, enriched using ProteoMiner treatment, and separated using sodium dodecyl sulfate-PAGE. After excision and digestion, the peptides were analyzed using liquid chromatography (LC) tandem mass spectrometry (MS/MS). The LC-MS/MS data were analyzed using PROC GLIMMIX of SAS (version 9.4, SAS Institute Inc., Cary, NC) and adjusted using the MULTTEST procedure. All other parameters were analyzed using PROC MIXED of SAS. No treatment differences were observed in dry matter intake, milk yield, general milk composition, plasma parameters, or rumen volatile fatty acid concentrations, indicating no shift in total energy or protein available. Milk urea N and plasma urea N concentrations were higher in the RDP group, indicating some shift in N partitioning due to diet. A total of 595 milk proteins were identified, with 83% of these proteins known to be involved in cellular processes. Although none of the low-abundance proteins identified by LC-MS/MS were affected by diet, feeding a diet high in RUP decreased ß-casein, κ-casein, and total milk casein concentration. Further investigations of the interactions between diet and the milk protein profile are needed to manipulate the milk proteome using diet.


Assuntos
Proteínas Alimentares/metabolismo , Lactação , Proteínas do Leite/metabolismo , Nitrogênio/metabolismo , Proteoma/metabolismo , Rúmen/metabolismo , Animais , Bovinos , Feminino , Gravidez , Distribuição Aleatória , Espectrometria de Massas em Tandem
5.
J Pain Symptom Manage ; 51(6): 994-1001, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27112311

RESUMO

CONTEXT: The oral route is compromised for nearly all patients approaching death. When agitation, seizures, or other intractable symptoms occur, a quick, discreet, comfortable, and effective alternate route for medication delivery that is easy to administer in the home setting is highly desirable. OBJECTIVES: To characterize the early absorption profile, variability, and comfort of phenobarbital given in microenema suspensions delivered via the Macy Catheter(®) (MC) vs. the same dose given via suppository. METHODS: This was a randomized, open-label, crossover study comparing the early absorption profile of equal doses of phenobarbital administered rectally in three treatment phases: phenobarbital suppository and two different microenemas with phenobarbital tablets crushed and suspended in 6 mL (MC-6) or 20 mL (MC-20) of tap water. RESULTS: Mean plasma phenobarbital concentrations at 10 minutes were 12× higher for MC-20 and 8× higher for MC-6 compared to suppository. Concentrations achieved in 30 minutes via MC-20 took almost three hours to achieve with suppository. Mean AUC values were higher for MC-20 and MC-6 (82% and 46%, respectively) vs. suppository (P < 0.05). There was less variability in absorption for MC-20 and MC-6 (1.4- to 1.9-fold difference) compared to a 4.4-fold difference via suppository. MC administrations were reported as "not uncomfortable" compared to suppositories, which were reported as "mildly uncomfortable" (P < 0.05). CONCLUSION: These results suggest phenobarbital oral tablets crushed and suspended in water and administered via the MC is superior to suppository in delivering the medication reliably and rapidly.


Assuntos
Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacocinética , Fenobarbital/administração & dosagem , Fenobarbital/farmacocinética , Administração Retal , Adulto , Área Sob a Curva , Cateterismo , Estudos Cross-Over , Feminino , Cuidados Paliativos na Terminalidade da Vida , Humanos , Masculino , Supositórios , Adulto Jovem
6.
Mol Oral Microbiol ; 30(2): 97-110, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25055881

RESUMO

The cell envelope of gram-negative bacteria serves a critical role in maintenance of cellular homeostasis, resistance to external stress, and host-pathogen interactions. Envelope protein composition is influenced by the physiological and environmental demands placed on the bacterium. In this study, we report a comprehensive compilation of cell envelope proteins from the periodontal and systemic pathogen Aggregatibacter actinomycetemcomitans VT1169, an afimbriated serotype b strain. The urea-extracted membrane proteins were identified by mass spectrometry-based shotgun proteomics. The membrane proteome, isolated from actively growing bacteria under normal laboratory conditions, included 648 proteins representing 27% of the predicted open reading frames in the genome. Bioinformatic analyses were used to annotate and predict the cellular location and function of the proteins. Surface adhesins, porins, lipoproteins, numerous influx and efflux pumps, multiple sugar, amino acid and iron transporters, and components of the type I, II and V secretion systems were identified. Periplasmic space and cytoplasmic proteins with chaperone function were also identified. A total of 107 proteins with unknown function were associated with the cell envelope. Orthologs of a subset of these uncharacterized proteins are present in other bacterial genomes, whereas others are found exclusively in A. actinomycetemcomitans. This knowledge will contribute to elucidating the role of cell envelope proteins in bacterial growth and survival in the oral cavity.


Assuntos
Aggregatibacter actinomycetemcomitans/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Membrana Celular/metabolismo , Parede Celular/metabolismo , Periplasma/metabolismo , Proteoma/metabolismo , Aggregatibacter actinomycetemcomitans/genética , Proteínas da Membrana Bacteriana Externa/genética , Sistemas de Secreção Bacterianos , Biologia Computacional , Genoma Bacteriano
7.
J Biomed Mater Res A ; 103(7): 2383-93, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25430523

RESUMO

In this study, we explored the concept of introducing asymmetry to cell shapes by patterned cell culture substrates, and investigated the consequence of this induced asymmetry to cell migration behaviors. Three patterns, named "Squares", "Grating", and "Arcs" were fabricated, representing different levels of rotational asymmetry. Using time-lapse imaging, we systematically compared the motility and directionality of mouse osteoblastic cells MC3T3-E1 cultured on these patterns. Cells were found to move progressively faster on "Arcs" than on "Grating", and cells on "Squares" were the slowest, suggesting that cell motility correlates with the level of rotational asymmetry of the repeating units of the pattern. Among these three patterns, on the "Arcs" pattern, the least symmetrical one, cells not only moved with the highest velocity but also the strongest directional persistence. Although this enhanced motility was not associated with the detected number of focal adhesion sites in the cells, the pattern asymmetry was reflected in the asymmetrical cell spreading. Cells on the "Arcs" pattern consistently displayed larger cytoplasmic protrusion on one side of the cell. This asymmetry in cell shape determined the direction and speed of cell migration. These observations suggest that topographical patterns that enhance the imbalance between the leading and trailing fronts of adherent cells will increase cell speed and control movement directions. Our discovery shows that complex cell behaviors such as the direction of cell movement are influenced by simple geometrical principles, which can be utilized as the design foundation for platforms that guide and sort cultured cells.


Assuntos
Movimento Celular , Forma Celular , Células 3T3 , Animais , Camundongos
8.
J Acoust Soc Am ; 136(3): 1101, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25190385

RESUMO

This paper extends a potential-based approach to active noise shielding with preservation of wanted sound in three-dimensional settings. The approach, which was described in a previous publication [Lim et al., J. Acoust. Soc. Am. 129(2), 717-725 (2011)], provides several significant advantages over conventional noise control methods. Most significantly, the methodology does not require any information including the characterization of sources, impedance boundary conditions and surrounding medium, and that the methodology automatically differentiates between the wanted and unwanted sound components. The previous publication proved the concept in one-dimensional conditions. In this paper, the approach for more realistic conditions is studied by numerical simulation and experimental validation in three-dimensional cases. The results provide a guideline to the implementation of the active shielding method with practical three-dimensional conditions. Through numerical simulation it is demonstrated that while leaving the wanted sound unchanged, the developed approach offers selective volumetric noise cancellation within a targeted domain. In addition, the method is implemented in a three-dimensional experiment with a white noise source in a semi-anechoic chamber. The experimental study identifies practical difficulties and limitations in the use of the approach for real applications.

9.
Neuroscience ; 242: 78-84, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23558090

RESUMO

Relay cells of dorsal lateral geniculate nucleus (LGN) receive a Class 1 glutamatergic input from the retina and a Class 2 input from cortical layer 6. Among the properties of Class 2 synapses is the ability to activate metabotropic glutamate receptors (mGluRs), and mGluR activation is known to affect thalamocortical transmission via regulating retinogeniculate and thalamocortical synapses. Using brain slices, we studied the effects of Group I (dihydroxyphenylglycine) and Group II ((2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine) mGluR agonists on retinogeniculate synapses. We showed that both agonists inhibit retinogeniculate excitatory postsynaptic currents (EPSCs) through presynaptic mechanisms, and their effects are additive and independent. We also found high-frequency stimulation of the layer 6 corticothalamic input produced a similar suppression of retinogeniculate EPSCs, suggesting layer 6 projection to LGN as a plausible source of activating these presynaptic mGluRs.


Assuntos
Corpos Geniculados/fisiologia , Inibição Neural/fisiologia , Receptores de Glutamato Metabotrópico/fisiologia , Retina/fisiologia , Transmissão Sináptica/fisiologia , Animais , Córtex Cerebral/fisiologia , Ciclopropanos/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Corpos Geniculados/efeitos dos fármacos , Glicina/análogos & derivados , Glicina/farmacologia , Camundongos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Estimulação Luminosa , Receptores de Glutamato Metabotrópico/agonistas , Resorcinóis/farmacologia , Retina/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Tálamo/fisiologia , Vias Visuais/fisiologia
10.
ISRN Pharmacol ; 2013: 641089, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533802

RESUMO

The mapping of the human genome and subsequent advancements in genetic technology had provided clinicians and scientists an understanding of the genetic basis of altered drug pharmacokinetics and pharmacodynamics, as well as some examples of applying genomic data in clinical practice. This has raised the public expectation that predicting patients' responses to drug therapy is now possible in every therapeutic area, and personalized drug therapy would come sooner than later. However, debate continues among most stakeholders involved in drug development and clinical decision-making on whether pharmacogenomic biomarkers should be used in patient assessment, as well as when and in whom to use the biomarker-based diagnostic tests. Currently, most would agree that achieving the goal of personalized therapy remains years, if not decades, away. Realistic application of genomic findings and technologies in clinical practice and drug development require addressing multiple logistics and challenges that go beyond discovery of gene variants and/or completion of prospective controlled clinical trials. The goal of personalized medicine can only be achieved when all stakeholders in the field work together, with willingness to accept occasional paradigm change in their current approach.

11.
J Acoust Soc Am ; 129(2): 717-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21361431

RESUMO

This paper describes an active sound control methodology based on difference potentials. The main feature of this methodology is its ability to automatically preserve "wanted" sound within a domain while cancelling "unwanted" noise from outside the domain. This method of preservation of the wanted sounds by active shielding control is demonstrated with various broadband and realistic sound sources such as human voice and music in multiple domains in a one-dimensional enclosure. Unlike many other conventional active control methods, the proposed approach does not require the explicit characterization of the wanted sound to be preserved. The controls are designed based on the measurements of the total field on the boundaries of the shielded domain only, which is allowed to be multiply connected. The method is tested in a variety of experimental cases. The typical attenuation of the unwanted noise is found to be about 20 dB over a large area of the shielded domain and the original wanted sound field is preserved with errors of around 1 dB and below through a broad frequency range up to 1 kHz.


Assuntos
Acústica , Modelos Teóricos , Ruído/prevenção & controle , Processamento de Sinais Assistido por Computador , Som , Acústica/instrumentação , Movimento (Física) , Pressão , Reprodutibilidade dos Testes , Espectrografia do Som , Fatores de Tempo , Vibração
12.
Mol Cell Proteomics ; 9(10): 2089-98, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20562470

RESUMO

Surface topography and texture of cell culture substrata can affect the differentiation and growth of adherent cells. The biochemical basis of the transduction of the physical and mechanical signals to cellular responses is not well understood. The lack of a systematic characterization of cell-biomaterial interaction is the major bottleneck. This study demonstrated the use of a novel subcellular fractionation method combined with quantitative MS-based proteomics to enable the robust and high-throughput analysis of proteins at the adherence interface of Madin-Darby canine kidney cells. This method revealed the enrichment of extracellular matrix proteins and membrane and stress fibers proteins at the adherence surface, whereas it shows depletion of extracellular matrix belonging to the cytoplasmic, nucleus, and lateral and apical membranes. The asymmetric distribution of proteins between apical and adherence sides was also profiled. Apart from classical proteins with clear involvement in cell-material interactions, proteins previously not known to be involved in cell attachment were also discovered.


Assuntos
Proteômica , Animais , Células Cultivadas , Cães , Proteínas da Matriz Extracelular/metabolismo , Espectrometria de Massas
13.
Psychiatr Serv ; 58(9): 1187-92, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17766564

RESUMO

OBJECTIVE: The most common ways of assessing adherence to oral antipsychotic medications in research and in clinical practice are self-report and physician report. This prospective study examined the agreement among measures of adherence to oral antipsychotic medications among 52 outpatients with schizophrenia. METHODS: Participants were assessed at baseline during a visit to their outpatient clinic and followed for 12 weeks. Adherence was assessed by using subjective measures (self-report and physician report) and objective measures (pill counts conducted in the home, electronic monitoring, and blood plasma concentrations). Electronic monitoring was used as an imperfect standard against which other methods were judged. RESULTS: Data from pill counts and from electronic monitoring were strongly correlated (r(k)=.61). Self-report and physicians' ratings of compliance were weakly correlated with pill count and electronic monitoring when compliance scores were examined with rank-order correlations (r(k)=.18-.32). When the sample was dichotomized into adherent and nonadherent groups on the basis of electronic monitoring or pill count (at least 80% adherent), neither physicians nor patients identified adherent behavior (kappa

Assuntos
Antipsicóticos/uso terapêutico , Cooperação do Paciente , Administração Oral , Adolescente , Adulto , Antipsicóticos/administração & dosagem , Antipsicóticos/sangue , Feminino , Visita Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Prospectivos , Esquizofrenia/tratamento farmacológico , Autorrevelação , Texas
14.
J Neurophysiol ; 93(2): 748-57, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15653787

RESUMO

We used an in vitro slice preparation of the lateral geniculate nucleus in cats and rats to study morphological correlates of triadic circuitry in relay cells. The three triadic elements involve a retinal synapse onto a GABAergic dendritic terminal of an interneuron, a synapse from the same retinal terminal onto a relay cell dendrite, and a synapse from the same interneuron terminal onto the same relay cell dendrite. We made whole cell recordings and labeled cells with biocytin. Previous methods were used to identify triadic circuitry based on evidence that the retinal terminal activates a metabotropic glutamate receptor on the interneuronal terminal. Thus application of (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (an agonist to that receptor) increases the rate of spontaneous inhibitory postsynaptic currents (sIPSCs) recorded in the relay cell, and if some of this increase remains with further addition of TTX (a TTX-insensitive response), a triad is indicated. We quantified the extent of the TTX-insensitive response and sought morphological correlates. In both rats and cats, this response correlated (negatively) with the number of primary dendrites and (positively) with polarity of the dendritic arbor. There was no correlation with cell size. Curiously, in cats, this response correlated with the presence of appendages at primary dendritic branches, but there was no such correlation in rats. These observations in cats map onto the X/Y classification, with X cells having triads, but it is not clear from our results if a comparable classification exists for rats.


Assuntos
Corpos Geniculados/citologia , Corpos Geniculados/fisiologia , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Gatos , Tamanho Celular/efeitos dos fármacos , Corpos Geniculados/efeitos dos fármacos , Técnicas In Vitro , Rede Nervosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tetrodotoxina/farmacologia
15.
J Urol ; 172(1): 331-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15201806

RESUMO

PURPOSE: Various strategies have recently emerged to improve the diagnostic prediction of prostate cancer (CaP). One such strategy includes the mass profiling of serum protein fractions selectively adsorbed onto chemically modified probes. In the current study we further validated this approach, while offering a more versatile, less expensive and yet equally predictive alternative to existing technologies. MATERIALS AND METHODS: A solid core lipophilic C-18 resin was used to extract and enrich the low molecular weight protein fraction from patient serum for further analysis by mass spectrometry. Mass spectra generated from a 48 patient training set were data mined using multivariate analysis to identify diagnostically significant protein peaks. These peaks were then used to test a blinded study set comprising 168 patients with common statistical algorithms and commercially available software packages. RESULTS: A total of 36 peaks generated from the training set were used to test the combined set of 168 serum samples obtained from 98 healthy individuals and 70 patients with CaP. We report a sensitivity of 94.1% and a specificity of 99.0% with 1 false-positive, 4 false-negative and 5 nondiagnosed cases. CONCLUSIONS: Our results further indicate that mass profiling of serological proteins provides a means for the accurate detection of CaP. In addition, our approach was found to be superior to chip based protocols, generating rich, sharp, highly reproducible spectra attainable in a high throughput manner and at minimal cost. This technique is also scaleable for subsequent protein characterization using multidimensional protein identification technologies. Finally, analyses of mass spectra with commercially available statistical applications was found to be highly effective in generating highly discriminatory m/z values for CaP diagnosis.


Assuntos
Biomarcadores Tumorais/análise , Proteínas Sanguíneas/análise , Neoplasias da Próstata/diagnóstico , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise Serial de Proteínas , Testes Sorológicos
16.
Pharmacotherapy ; 24(4): 477-81, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15098801

RESUMO

STUDY OBJECTIVE: To compare the relative bioavailability of an extemporaneous ondansetron capsule formulation with that of an identical dose of the commercially available solution formulation. DESIGN: Open-label, randomized, two-way crossover study. SETTING: University-affiliated research laboratory. SUBJECTS: Sixteen (eight men, eight women) healthy, nonsmoking volunteers. INTERVENTION: Participants were randomly assigned to receive a 4-mg dose of either the commercially available ondansetron solution or the extemporaneous ondansetron capsule formulation. Blood sampling was performed over 12 hours after dosing. After a washout period of at least 3 days, each participant was switched to the alternate formulation, and blood sampling was repeated. MEASUREMENTS AND MAIN RESULTS: Ondansetron was well absorbed after administration of both formulations, with the solution achieving a faster rate of drug absorption over the first hour of dosing. After the peak plasma concentration was achieved, the plasma concentration-time curves of both formulations declined at a similar steady rate. There were no significant differences in pharmacokinetic parameters between the two formulations, and the relative bioavailability of the capsule versus the solution formulation was 101%. CONCLUSIONS: Similar concentration-time curves and pharmacokinetic parameters were achieved with the two formulations. The commercially available solution would be a useful alternative formulation for administration of low-dose ondansetron in research and clinical settings.


Assuntos
Antieméticos/farmacocinética , Ondansetron/farmacocinética , Adulto , Antieméticos/administração & dosagem , Antieméticos/sangue , Área Sob a Curva , Disponibilidade Biológica , Cápsulas , Estudos Cross-Over , Feminino , Gelatina , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Ondansetron/administração & dosagem , Ondansetron/sangue , Soluções Farmacêuticas
17.
J Clin Pharmacol ; 43(11): 1274-82, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14551182

RESUMO

The objective of this study was to investigate pharmacokinetic and pharmacodynamic interactions between midazolam and fluoxetine, fluvoxamine, nefazodone, and ketoconazole. Forty healthy subjects were randomized to receive one of the four study drugs for 12 days in a parallel study design: fluoxetine 60 mg per day for 5 days, followed by 20 mg per day for 7 days; fluvoxamine titrated to a daily dose of 200 mg; nefazodone titrated to a daily dose of 400 mg; or ketoconazole 200 mg per day. All 40 subjects received oral midazolam solution before and after the 12-day study drug regimen. Blood samples for determination of midazolam concentrations were drawn for 24 hours after each midazolam dose and used for the calculation of pharmacokinetic parameters. The effects of the study drugs on midazolam pharmacodynamics were assessed using the symbol digit modalities test (SDMT). The mean area under the curve (AUC) for midazolam was increased 771.9% by ketoconazole and 444.0% by nefazodone administration. However, there was no significant change in midazolam AUC as a result of fluoxetine (13.4% decrease) and a statistical trend for fluvoxamine (66.1% increase) administration. Pharmacodynamic data are consistent with pharmacokinetic data indicating that nefazodone and ketoconazole resulted in significant increases in midazolam-related cognition impairment. The significant impairment in subjects' cognitive function reflects the changes in midazolam clearance after treatment with ketoconazole and nefazodone. These results suggest that caution with the use of midazolam is warranted with potent CYP3A4 inhibitors.


Assuntos
Fluoxetina/farmacocinética , Fluvoxamina/farmacocinética , Cetoconazol/farmacocinética , Midazolam/farmacocinética , Triazóis/farmacocinética , Administração Oral , Adulto , Análise de Variância , Área Sob a Curva , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Feminino , Fluoxetina/administração & dosagem , Fluoxetina/farmacologia , Fluvoxamina/administração & dosagem , Fluvoxamina/farmacologia , Humanos , Cetoconazol/administração & dosagem , Cetoconazol/farmacologia , Masculino , Midazolam/administração & dosagem , Midazolam/farmacologia , Piperazinas , Triazóis/administração & dosagem , Triazóis/farmacologia
18.
Vet Immunol Immunopathol ; 94(3-4): 105-12, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12909407

RESUMO

A hexameric rhamnose-specific lectin with a molecular mass of 205kDa and exhibiting some N-terminal sequence similarity to other fish lectins was isolated from roe of the grass carp (Ctenopharyngodon idellus) by affinity chromatography on rhamnose-Sepharose and ion exchange chromatography by fast protein liquid chromatography on a Mono S column. The lectin exhibited mitogenic activity toward murine splenocytes with a potency lower than that of the plant lectin ConA. It exerted a stimulatory effect at a concentration of 10 micro g/ml on the phagocytic activity of seabream (Sparus sarba) macrophages. It was unstable toward heat (temperature > or =40 degrees C), acid (0.1M HCl), alkali (0.1M NaOH), trypsin and succinylation.


Assuntos
Adjuvantes Imunológicos/farmacologia , Carpas/metabolismo , Lectinas/farmacologia , Ramnose/metabolismo , Adjuvantes Imunológicos/isolamento & purificação , Adjuvantes Imunológicos/metabolismo , Sequência de Aminoácidos , Animais , Carpas/imunologia , Cromatografia de Afinidade/veterinária , Cromatografia por Troca Iônica/veterinária , Estabilidade de Medicamentos , Hemaglutinação/imunologia , Temperatura Alta , Concentração de Íons de Hidrogênio , Lectinas/imunologia , Lectinas/isolamento & purificação , Lectinas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Dourada , Alinhamento de Sequência , Análise de Sequência de Proteína , Baço/citologia , Baço/efeitos dos fármacos , Tripsina/metabolismo
19.
Neuropsychopharmacology ; 28(5): 961-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12644842

RESUMO

Olanzapine has previously been shown to have predominant metabolism by cytochrome (CYP) P450 1A2. Caffeine has been shown to provide an accurate phenotypic probe for measuring CYP1A2 activity. The purpose of this study is to determine if a significant correlation exists between olanzapine disposition and caffeine metabolic ratios. Subjects were phenotyped for CYP1A2 activity with caffeine probe methodology. After 200-mg caffeine administration, blood (4 h), saliva (6 and 10 h), and urine (8 h total) were collected for high-performance liquid chromatography (HPLC) analysis of caffeine and its metabolites.CYP1A2 activity was measured as plasma (PMR(4 h)), saliva (SMR(6 h) and SMR(10 h)), and three urinary metabolic (UMR1(8 h), UMR2(8 h), and UMR3(8 h)) ratios. Each of the 14 healthy nonsmokers (13 male) received a single 10 mg olanzapine dose after which blood was collected for HPLC determination of olanzapine concentrations at predose and at 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 12, 24, 48, 72, 96, and 120 h postdose. Olanzapine pharmacokinetic parameters in this study were similar to those previously published. All caffeine metabolic ratios (PMR(4 h), SMR(6 h), SMR(10 h), UMR1(8 h), and UMR2(8 h)) significantly correlated with each other (p <0.001) except for UMR3(8 h), which did not correlate. A significant correlation (p <0.05) was also found between olanzapine clearance and PMR(4 h) (r=0.701), SMR(6 h) (r=0.644), SMR(10 h) (r=0.701), UMR1(8 h) (r=0.745), and UMR2(8 h) (r=0.710). A negative correlation was observed between olanzapine clearance and UMR3(8 h) (r=-0.029, p=NS). A significant correlation was found between olanzapine clearance and various caffeine metabolic ratios. Interpatient variability in CYP1A2 activity may explain the wide interpatient variability in olanzapine disposition. Compounds that modulate CYP1A2 activity may be expected to alter olanzapine pharmacokinetics accordingly.


Assuntos
Cafeína/metabolismo , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Fenótipo , Pirenzepina/análogos & derivados , Pirenzepina/metabolismo , Adulto , Área Sob a Curva , Benzodiazepinas , Cafeína/farmacologia , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Taxa de Depuração Metabólica/fisiologia , Olanzapina , Pirenzepina/farmacocinética
20.
Protein Expr Purif ; 26(3): 378-85, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12460761

RESUMO

A rhamnose-specific lectin was isolated from ovaries of the grass carp (Ctenopharyngodon idellus). The grass carp lectin possesses a molecular mass of 205 kDa. It is composed of six subunits each with a molecular mass of 35 kDa. The N-terminal amino acid sequence of the grass carp shows similarity to those of other fish species with 26-35% amino acid identity. It is mitogenic toward murine splenocytes and peritoneal exudate cells.


Assuntos
Carpas/imunologia , Sistema Imunitário/efeitos dos fármacos , Lectinas/isolamento & purificação , Lectinas/farmacologia , Ovário/química , Ramnose/metabolismo , Sequência de Aminoácidos , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Sistema Imunitário/metabolismo , Interferon gama/genética , Interleucina-2/genética , Lectinas/química , Lectinas/metabolismo , Camundongos , Mitógenos/farmacologia , Dados de Sequência Molecular , Peso Molecular , Análise de Sequência de Proteína , Homologia de Sequência , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo
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