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1.
BMC Pregnancy Childbirth ; 23(1): 303, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120529

RESUMO

BACKGROUND: In low- and middle-income countries, approximately two thirds of maternal deaths occur in the postpartum period. Yet, care for women beyond 24 h after discharge is limited. The objective of this systematic review is to summarize current evidence on socio-demographic and clinical risk factors for (1) postpartum mortality and (2) postpartum hospital readmission. METHODS: A combination of keywords and subject headings (i.e. MeSH terms) for postpartum maternal mortality or readmission were searched. Articles published up to January 9, 2021 were identified in MEDLINE, EMBASE, and CINAHL databases, without language restrictions. Studies reporting socio-demographic or clinical risk factors for postpartum mortality or readmission within six weeks of delivery among women who delivered a livebirth in a low- or middle-income country were included. Data were extracted independently by two reviewers based on study characteristics, population, and outcomes. Included studies were assessed for quality and risk of bias using the Downs and Black checklist for ratings of randomized and non-randomized studies. RESULTS: Of 8783 abstracts screened, seven studies were included (total N = 387,786). Risk factors for postpartum mortality included Caesarean mode of delivery, nulliparity, low or very low birthweight, and shock upon admission. Risk factors for postpartum readmission included Caesarean mode of delivery, HIV positive serostatus, and abnormal body temperature. CONCLUSIONS: Few studies reported individual socio-demographic or clinical risk factors for mortality or readmission after delivery in low- and middle-income countries; only Caesarean delivery was consistently reported. Further research is needed to identify factors that put women at greatest risk of post-discharge complications and mortality. Understanding post-discharge risk would facilitate targeted postpartum care and reduce adverse outcomes in women after delivery. TRIAL REGISTRATION: PROSPERO registration number: CRD42018103955.


Assuntos
Assistência ao Convalescente , Readmissão do Paciente , Gravidez , Feminino , Humanos , Países em Desenvolvimento , Mortalidade Materna , Alta do Paciente , Período Pós-Parto , Fatores de Risco
2.
Chaos ; 27(10): 103125, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29092454

RESUMO

In this work, we consider a ring of coupled electronic (Wien-bridge) oscillators from a perspective combining modeling, simulation, and experimental observation. Following up on earlier work characterizing the pairwise interaction of Wien-bridge oscillators by Kuramoto-Sakaguchi phase dynamics, we develop a lattice model for a chain thereof, featuring an exponentially decaying spatial kernel. We find that for certain values of the Sakaguchi parameter α, states of traveling phase-domain fronts involving the coexistence of two clearly separated regions of distinct dynamical behavior, can establish themselves in the ring lattice. Experiments and simulations show that stationary coexistence domains of synchronization only manifest themselves with the introduction of a local impurity; here an incoherent cluster of oscillators can arise reminiscent of the chimera states in a range of systems with homogeneous oscillators and suitable nonlocal interactions between them.

3.
Int J Obes (Lond) ; 40(10): 1515-1522, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27457416

RESUMO

OBJECTIVE: Large portions of energy-dense foods drive energy intake but the brain mechanisms underlying this effect are not clear. Our main objective was to investigate brain function in response to food images varied by portion size (PS) and energy density (ED) in children using functional magnetic resonance imaging (fMRI). METHODS AND DESIGN: Blood-oxygen-level-dependent (BOLD) fMRI was completed in 36 children (ages 7-10 years) after a 2-h fast while viewing food images at two levels of PS (Large PS, Small PS) and two levels of ED (High ED, Low ED). Children rated perceived fullness pre- and post-fMRI, as well as liking of images on visual analog scales post-fMRI. Anthropometrics were completed 4 weeks before the fMRI. Large PS vs Small PS and High ED vs Low ED were compared with region-of-interest analyses using Brain Voyager v 2.8. RESULTS: Region-of-interest analyses revealed that activation in the right inferior frontal gyrus (P=0.03) was greater for Large PS vs Small PS. Activation was reduced for High ED vs Low ED in the left hypothalamus (P=0.03). Main effects were no longer significant after adjustment for pre-fMRI fullness and liking ratings (PS, P=0.92; ED, P=0.58). CONCLUSION: This is the first fMRI study to report increased activation to large portions in a brain region that is involved in inhibitory control. These findings may contribute to understanding why some children overeat when presented with large portions of palatable food.


Assuntos
Regulação do Apetite/fisiologia , Ingestão de Energia/fisiologia , Comportamento Alimentar/fisiologia , Preferências Alimentares/psicologia , Hipotálamo/fisiologia , Obesidade Infantil/fisiopatologia , Tamanho da Porção/psicologia , Mapeamento Encefálico , Criança , Comportamento de Escolha/fisiologia , Sinais (Psicologia) , Jejum , Feminino , Alimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Obesidade Infantil/prevenção & controle , Obesidade Infantil/psicologia , Percepção , Estimulação Luminosa , Estados Unidos
4.
BMC Infect Dis ; 16: 194, 2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27146090

RESUMO

BACKGROUND: Antibiotic resistant strains of Acinetobacter baumannii have been responsible for an increasing number of nosocomial infections including bacteremia and ventilator-associated pneumonia. In this study, we analyzed 38 isolates of A. baumannii obtained from two hospital outbreaks in Los Angeles County for the molecular epidemiology, antimicrobial susceptibility and resistance determinants. METHODS: Pulsed field gel electrophoresis, tri-locus multiplex PCR and multi-locus sequence typing (Pasteur scheme) were used to examine clonal relationships of the outbreak isolates. Broth microdilution method was used to determine antimicrobial susceptibility of these isolates. PCR and subsequent DNA sequencing were employed to characterize antibiotic resistance genetic determinants. RESULTS: Trilocus multiplex PCR showed these isolates belong to Global Clones I and II, which were confirmed to ST1 and ST2, respectively, by multi-locus sequence typing. Pulsed field gel electrophoresis analysis identified two clonal clusters, one with 20 isolates (Global Clone I) and the other with nine (Global Clone II), which dominated the two outbreaks. Antimicrobial susceptibility testing using 14 antibiotics indicated that all isolates were resistant to antibiotics belonging to four or more categories of antimicrobial agents. In particular, over three fourth of 38 isolates were found to be resistant to both imipenem and meropenem. Additionally, all isolates were found to be resistant to piperacillin, four cephalosporin antibiotics, ciprofloxacin and levofloxacin. Resistance phenotypes of these strains to fluoroquinolones were correlated with point mutations in gyrA and parC genes that render reduced affinity to target proteins. ISAba1 was detected immediately upstream of the bla OXA-23 gene present in those isolates that were found to be resistant to both carbapenems. Class 1 integron-associated resistance gene cassettes appear to contribute to resistance to aminoglycoside antibiotics. CONCLUSION: The two outbreaks were found to be dominated by two clonal clusters of A. baumannii belonging to MLST ST1 and ST2. All isolates were resistant to antibiotics of at least four categories of antimicrobial agents, and their antimicrobial susceptibility profiles correlate well with genetic determinants. The results of this study will facilitate our understanding of the molecular epidemiology, antimicrobial susceptibility and mechanisms of resistance of A. baumannii obtained from Los Angeles hospitals.


Assuntos
Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Proteínas de Bactérias/genética , California , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , DNA Girase/genética , DNA Topoisomerase IV , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Humanos , Integrons , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , beta-Lactamases/genética
5.
Matern Child Health J ; 20(10): 2209-15, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27299903

RESUMO

Introduction The prevalence of ethanol use in many Sub-Saharan African countries is high, but little research exists on use during pregnancy. The objective of this study was to assess the prevalence and predictors of ethanol use among pregnant women in Southwestern Uganda. Methods This descriptive, cross-sectional study was conducted in the maternity ward at Mbarara Regional Referral Hospital (MRRH). All pregnant women giving birth at MRRH between September 23, 2013 and November 23, 2013 were eligible for enrollment. The primary outcome was the proportion of women with ethanol use during pregnancy as determined by self-report. Secondary outcomes included the proportion with positive fatty acid ethyl ester (FAEE) results (indicating ethanol use) and positive TWEAK questionnaire results (indicating possible problem drinking). Predictors of ethanol use were assessed and stratified by patterns of ethanol intake. Results Overall, 505 mother-child dyads enrolled in the study. The proportion of women who reported any ethanol use during pregnancy was 16 % (n = 81, 95 % CI 13-19 %) and the prevalence of heavy drinking 6.3 % (n = 32, 95 % CI 3.8-7.9 %). The strongest predictor of use during pregnancy was pre-pregnancy use, with maternal education as a protective factor. Few neonates (n = 11, 2 %) tested positive for FAEE > 2.00 nmol/g in meconium. The TWEAK questionnaire captured 75 % of women who reported moderate/heavy drinking and aligned more with self-reported ethanol use than meconium results. Conclusions The substantial prevalence and clear predictors of ethanol use suggest that legislative action and educational interventions to increase awareness of potential harms could assist in efforts to decrease use during pregnancy in Southwestern Uganda.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/epidemiologia , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Gestantes , Adulto , Consumo de Bebidas Alcoólicas/etnologia , Consumo de Bebidas Alcoólicas/metabolismo , Estudos Transversais , Feminino , Humanos , Troca Materno-Fetal , Mecônio/química , Gravidez , Gestantes/etnologia , Prevalência , Fatores Socioeconômicos , Inquéritos e Questionários , Uganda/epidemiologia
6.
Phys Rev Lett ; 108(8): 084101, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22463533

RESUMO

We show experimentally and numerically that an intrinsic localized mode (ILM) can be stably produced (and experimentally observed) via subharmonic, spatially homogeneous driving in the context of a nonlinear electrical lattice. The precise nonlinear spatial response of the system has been seen to depend on the relative location in frequency between the driver frequency, ω(d), and the bottom of the linear dispersion curve, ω(0). If ω(d)/2 lies just below ω(0), then a single ILM can be generated in a 32-node lattice, whereas, when ω(d)/2 lies within the dispersion band, a spatially extended waveform resembling a train of ILMs results. To our knowledge, and despite its apparently broad relevance, such an experimental observation of subharmonically driven ILMs has not been previously reported.

7.
J Exp Med ; 144(3): 586-603, 1976 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-956726

RESUMO

The primary response of the popliteal node to Salmonella lipopolysaccharide was studied in the sheep. All three classes of immunoglobulin IgG1, igG2, and IgM were produced by both free-floating cells in the lymph and by cells within the pymph node throughout the immune responce which extended over a period of at least 20 days.. Most of the immunoglobulins were found to be nonspecific for the antigen when tested by a binding assay. It was calculated from the binding assay that far more antigen-specific IgG molecules were produced than IgM molecules. The proportion of IgM and IgG1 which showed affinity for Salmonella organisms increased throughout the response. IgG2 had no affinity for the antigen until around 480 h after challenge. When a hemagglutination assay was used to measure antibody production, most of the specific antibody produced during the response was found to be IgM. Blast cells produced most of the immunoglobulin during the first 4 days of the response, and these cells were responsible for almost all of the IgM production. Differences were observed in the relative amounts of IgG and IgM produced by the cells within the node and by free-floating cells in the efferent lymph. The free-floating cells in lymph synthesized and secreted relatively more IgM and relatively less IgG than did cells within the lymph node. Both populations of cells, however, secreted much more IgG than IgM.


Assuntos
Formação de Anticorpos , Antígenos de Bactérias , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Linfonodos/imunologia , Polissacarídeos Bacterianos/imunologia , Animais , Especificidade de Anticorpos , Divisão Celular , Lipopolissacarídeos/imunologia , Linfa/imunologia , Linfonodos/metabolismo , Linfócitos/imunologia , Salmonella/imunologia , Ovinos , Fatores de Tempo
8.
J Cell Biol ; 97(4): 1299-302, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6311842

RESUMO

Friend murine erythroleukemia cells underwent apparently normal erythropoiesis when treated with dimethyl sulfoxide. One of the earliest events associated with this induction was a decrease in ouabain sensitive 86Rb+ uptake, an assay of the plasma membrane Na,K(ATPase). Ammonium vanadate (10 microM) blocked differentiation of these cells without affecting cell viability. Vanadium was taken up by Friend cells and prevented the dimethyl sulfoxide-induced decrease in ouabain sensitive 86Rb+ uptake. Vanadate reactivated 86Rb+ transport previously inhibited by dimethyl sulfoxide treatment but had no affect on 86Rb+ transport in untreated cells. These results suggest an essential role for the (Na,K)ATPase in cell differentiation.


Assuntos
Eritropoese/efeitos dos fármacos , Canais Iônicos/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Vanádio/farmacologia , Animais , Linhagem Celular , Dimetil Sulfóxido/farmacologia , Relação Dose-Resposta a Droga , Leucemia Eritroblástica Aguda , Camundongos , Potássio/metabolismo , Rubídio/metabolismo , Sódio/metabolismo , Vanadatos
9.
J Appl Microbiol ; 106(5): 1722-33, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19226383

RESUMO

AIMS: To determine the antimicrobial resistant profiles and clonality of Campylobacter coli isolated from clinically ill humans and retail meats. METHODS AND RESULTS: A total of 98 C. coli isolates (20 from humans and 78 from retail meats) were phenotypically characterized. Antimicrobial susceptibility testing was done using agar dilution method for ciprofloxacin, gentamicin, erythromycin and doxycycline. Seventy C. coli isolates including humans (n = 20) and retail meats (n = 50) were genotyped by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Resistance to ciprofloxacin was found in 29% and 15% of isolates from retail meats and humans. We observed 61 PFGE profiles using two enzymes (SmaI, KpnI) with an Index of discrimination of 0.99, whereas MLST generated 37 sequence types. Two clonal complexes were identified with 58 (82%) C. coli isolates clustered in the ST-828 complex. CONCLUSIONS: Resistance to ciprofloxacin and erythromycin was identified in C. coli obtained from retail meats and ill humans. PFGE typing of C. coli isolates was more discriminatory than MLST. Grouping of C. coli isolates (82%) by MLST in ST-828 clonal complex indicates a common ancestry. SIGNIFICANCE AND IMPACT OF THE STUDY: A high frequency of resistance found to ciprofloxacin and erythromycin is concerning from food safety perspective. PFGE using single or double restriction enzymes was found to be more discriminatory than MLST for genotyping C. coli. Overall, the C. coli populations recovered from humans and retail meats were genotypically diverse.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter coli/classificação , Campylobacter coli/genética , Carne/microbiologia , Animais , Antibacterianos/farmacologia , Campylobacter coli/efeitos dos fármacos , Bovinos , Galinhas , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Variação Genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Filogenia , Suínos , Perus
10.
Phys Rev E ; 100(6-1): 062114, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31962490

RESUMO

We examine theoretically and experimentally the localized electrical modes existing in a bi-inductive electrical lattice containing a bulk or a surface capacitive impurity. By means of the formalism of lattice Green's functions, we are able to obtain closed-form expressions for the frequencies of the impurity (bound-state) eigenmodes and for their associated spatial profiles. This affords us a systematic understanding of how these mode properties change as a function of the system parameters. We test these analytical results against experimental measurements, in both the bulk and surface cases, and find very good agreement. Last, we turn to a series of quench experiments, where either a parameter of the lattice or the lattice geometry itself is rapidly switched between two values or configurations. In all cases, we are able to naturally explain the results of such quench experiments from the larger analytical picture that emerges as a result of the detailed characterization of the impurity-mode solution branches.

11.
Phys Rev E ; 99(3-1): 032206, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30999528

RESUMO

We observe dark and bright intrinsic localized modes (ILMs), also known as discrete breathers, experimentally and numerically in a diatomic-like electrical lattice. The experimental generation of dark ILMs by driving a dissipative lattice with spatially homogenous amplitude is, to our knowledge, unprecedented. In addition, the experimental manifestation of bright breathers within the band gap is also novel in this system. In experimental measurements the dark modes appear just below the bottom of the top branch in frequency. As the frequency is then lowered further into the band gap, the dark ILMs persist, until the nonlinear localization pattern reverses and bright ILMs appear on top of the finite background. Deep into the band gap, only a single bright structure survives in a lattice of 32 nodes. The vicinity of the bottom band also features bright and dark self-localized excitations. These results pave the way for a more systematic study of dark breathers and their bifurcations in diatomic-like chains.

12.
Pediatr Obes ; 14(2): e12436, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30019382

RESUMO

BACKGROUND: Portion size influences intake (i.e. the portion size effect [PSE]), yet determinants of susceptibility to the PSE are unclear. OBJECTIVE: We tested whether children who reported an episode of loss of control (LOC) eating over the last 3 months would be more susceptible to the PSE and would show differential brain responses to food cues compared with children with no-LOC. METHODS: Across five sessions, children (n = 47; 7-10 years) consumed four test meals at 100%, 133%, 167% and 200% conditions for portion size and completed a functional magnetic resonance imaging scan while viewing pictures of foods varied by portion size and energy density (ED). Incidence of LOC over the past 3 months was self-reported. Random coefficient models were tested for differences in the shape of the PSE curve by LOC status. A whole-brain analysis was conducted to determine response to food cues during the functional magnetic resonance imaging. RESULTS: Reported LOC (n = 13) compared with no-LOC (n = 34) was associated with increased susceptibility to the PSE, as evidenced by a positive association with the linear slope (P < 0.005), and negative association with the quadratic slope (P < 0.05) of the intake curve. Children who reported LOC compared with no-LOC showed increased activation in the left cerebellum to small relative to large portions (P < 0.01) and right cerebellum to High-ED relative to Low-ED food cues (P < 0.01). CONCLUSION: Children who reported LOC were more susceptible to the PSE and showed alterations in food-cue processing in the cerebellum, a hindbrain region implicated in satiety signalling.


Assuntos
Encéfalo/fisiologia , Sinais (Psicologia) , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Tamanho da Porção , Antropometria , Encéfalo/diagnóstico por imagem , Criança , Estudos Cross-Over , Feminino , Alimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(6 Pt 2): 066601, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18643384

RESUMO

The emergence of very stable traveling intrinsic localized modes (ILMs) locked to a uniform driver is demonstrated in a discrete electrical transmission line. The speed of these traveling ILMs is tunable by the driver amplitude and frequency. It is found to be quite sensitive to the ratio of intersite to on-site nonlinearity. The number of traveling ILMs can also be selected via the driving conditions and appears to be the result of a spatiotemporal pattern selection process.

14.
J Vet Intern Med ; 30(3): 819-26, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27013187

RESUMO

BACKGROUND: Dysregulated apoptosis is a hallmark of tumorigenesis, and is also involved in resistance to cytotoxic treatment, and might be relevant in lymphoma in dogs. HYPOTHESIS/OBJECTIVES: That Bcl-2/Bax expression patterns differ between lymphoma immunophenotypes, and that Bcl-2/Bax ratio is correlated with prognosis. ANIMALS: Fifty-five client-owned dogs with multicentric lymphoma and 5 healthy dogs. METHODS: Prospective, case-control study. We compared 3 methods (flow cytometry, qRT-PCR, Western blot) for Bcl-2 and Bax quantification in a subset of dogs. The effect of time on Bcl-2/Bax ratios measured by flow cytometry was assessed in lymphoma cell lines. Immunophenotype and Bcl-2/Bax expression by flow cytometry were determined in LN aspirates from all dogs with multicentric lymphoma compared to healthy dogs. Progression-free survival (PFS) was retrospectively evaluated in a group of dogs all receiving similar treatment. RESULTS: Bcl-2/Bax ratios remain consistent for at least 5 days after sample collection. Bcl-2/Bax ratio was higher in dogs with T-cell lymphoma (TCL; median 0.97, range 0.37-1.36) compared to B-cell lymphoma (BCL; median 0.36, range 0.07-1.45) (P < .0001) and normal dogs (median 0.36, range 0.21-0.48) (P = .0006), respectively. Dogs with Bcl-2/Bax ratios higher than the median of the group experienced a median PFS of 101 days and dogs with ratios equal and lower than the median had PFS of 130 days (P = .19). CONCLUSIONS AND CLINICAL IMPORTANCE: Higher intrinsic resistance to apoptosis following cytotoxic treatment might contribute to the less favorable prognosis associated with multicentric TCL in dogs. Whether Bcl-2/Bax will be helpful to identify canine BCL and TCL with more aggressive and more indolent behavior, respectively, should be evaluated in larger prospective clinical studies.


Assuntos
Doenças do Cão/patologia , Linfonodos/metabolismo , Linfoma de Células B/veterinária , Linfoma de Células T/veterinária , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/genética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Apoptose , Estudos de Casos e Controles , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Citometria de Fluxo/veterinária , Regulação Neoplásica da Expressão Gênica , Linfonodos/patologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/patologia , Masculino , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sístole , Resultado do Tratamento , Proteína X Associada a bcl-2/metabolismo
15.
Phys Rev E ; 94(6-1): 062212, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28085391

RESUMO

We derive the Kuramoto-Sakaguchi model from the basic circuit equations governing two coupled Wien-bridge oscillators. A Wien-bridge oscillator is a particular realization of a tunable autonomous oscillator that makes use of frequency filtering (via an RC bandpass filter) and positive feedback (via an operational amplifier). In the past few years, such oscillators have started to be utilized in synchronization studies. We first show that the Wien-bridge circuit equations can be cast in the form of a coupled pair of van der Pol equations. Subsequently, by applying the method of multiple time scales, we derive the differential equations that govern the slow evolution of the oscillator phases and amplitudes. These equations are directly reminiscent of the Kuramoto-Sakaguchi-type models for the study of synchronization. We analyze the resulting system in terms of the existence and stability of various coupled oscillator solutions and explain on that basis how their synchronization emerges. The phase-amplitude equations are also compared numerically to the original circuit equations and good agreement is found. Finally, we report on experimental measurements of two coupled Wien-bridge oscillators and relate the results to the theoretical predictions.

16.
Biochim Biophys Acta ; 1089(2): 257-8, 1991 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-2054386

RESUMO

Porcine interleukin 2 (IL-2) cDNA was cloned by polymerase chain reaction (PCR), using primers derived from the corresponding bovine sequence. The resulting porcine DNA sequence encodes a 154 residue IL-2 primary translation product. Comparison of the mature, secreted form of porcine IL-2 with those of other species was carried out in an attempt to identify differences that might contribute to the observed differing species specificities.


Assuntos
DNA/genética , Interleucina-2/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Bovinos , Clonagem Molecular , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Biossíntese de Proteínas , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/metabolismo , Ovinos , Especificidade da Espécie , Suínos
17.
J Econ Entomol ; 98(6): 2028-32, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16539129

RESUMO

Strain distribution for the alfalfa weevil, Hypera postica (Gyllenhal), was determined for the five major alfalfa-growing regions of New Mexico. Mitochondrial DNA from field-collected weevils at each location was digested and sequenced to differentiate among strains. Eastern, Egyptian, and western strains were recovered, along with a population not matching any known strain. The majority of sites examined had populations of two strains intermingled within a field. This is the first confirmation of the presence of all three strains within the same geographic region. Possible implications for alfalfa weevil management are discussed.


Assuntos
Gorgulhos/classificação , Gorgulhos/genética , Animais , DNA Mitocondrial/genética , Demografia , Genes de Insetos/genética , Medicago sativa/parasitologia , New Mexico
18.
Artigo em Inglês | MEDLINE | ID: mdl-26651767

RESUMO

We explore the collective phase dynamics of Wien-bridge oscillators coupled resistively. We carefully analyze the behavior of two coupled oscillators, obtaining a transformation from voltage to effective phase. From the phase dynamics we show that the coupling can be quantitatively described by Sakaguchi's modification to the Kuramoto model. We also examine an ensemble of oscillators whose frequencies are taken from a flat distribution within a fixed frequency interval. We characterize in detail the synchronized cluster, its initial formation, as well as its effect on unsynchronized oscillators, all as a function of a global coupling strength.

19.
Vet Immunol Immunopathol ; 168(3-4): 242-8, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26553299

RESUMO

Flow cytometric analysis of canine lymphoma sometimes demonstrates a mixed population of CD45+ and CD45- lymphocytes. Recently, indolent forms of canine lymphoma have been described which are associated with the loss of CD45 expression, warranting further investigation of the role of CD45 in canine lymphoma. The purpose of this study was to compare morphology and assess clonal origin between CD45+ and CD45- lymphocyte populations identified by flow cytometry in confirmed cases of canine B- and T-cell lymphoma. Our hypothesis was that the CD45- population of lymphocytes represented a phenotypic variant of the CD45+ population. Fifteen client-owned dogs with lymphoma and distinct CD45+ and CD45- lymphocyte populations identified by flow cytometry were identified for a blinded, prospective assessment of morphology and clonal origin (B cell or T cell) between populations of sorted CD45+ and CD45- cells. Lymphocytes were isolated from 11 dogs for paired cytologic evaluation. In 10/11 dogs, the CD45+ and CD45- samples were similar (95% C.I., 0.301-1.00). DNA was harvested from sorted populations of CD45+ and CD45- cells from 12/15 dogs and PARR analysis produced amplicons of identical size from both populations, indicating that 100% (12/12) were of the same lineage, B cell or T cell (95% C.I., 0.757-1.00). Collectively, our data suggests that the CD45- population identified in dogs with lymphoma represents a phenotypic variant of the CD45+ population.


Assuntos
Linfócitos B/metabolismo , Doenças do Cão/metabolismo , Citometria de Fluxo/veterinária , Antígenos Comuns de Leucócito/metabolismo , Linfoma/veterinária , Linfócitos T/metabolismo , Animais , Doenças do Cão/imunologia , Cães , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Antígenos Comuns de Leucócito/genética , Linfoma/metabolismo , Masculino
20.
Hypertension ; 10(5 Pt 2): I93-4, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2824373

RESUMO

A 6.5-kilobase fragment of genomic DNA from mutant mouse cells under ouabain selection pressure conferred ouabain resistance when transfected into ouabain-sensitive CV1 green monkey fibroblasts. Ouabain resistance was induced in the presence of 10 microM ouabain. Amiloride (500 microM) completely blocked ouabain-insensitive 86Rb+ uptake into these cells. Plasma membranes from these cells demonstrated little sodium-dependent adenosine triphosphatase (ATPase) activity but had potassium-dependent and ouabain-resistant p-nitrophenylphosphatase activity. Like Na+,K+-ATPase this activity was vanadate- and sodium-inhibitable. Also, like the Na+,K+-ATPase, sodium inhibition of the p-nitrophenylphosphatase was reversed by 10 microM adenosine 5'-triphosphate.


Assuntos
4-Nitrofenilfosfatase/metabolismo , Amilorida/farmacologia , Membrana Celular/metabolismo , Ouabaína/farmacologia , Monoéster Fosfórico Hidrolases/metabolismo , Potássio/metabolismo , 4-Nitrofenilfosfatase/antagonistas & inibidores , 4-Nitrofenilfosfatase/genética , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Linhagem Celular , Chlorocebus aethiops , Resistência a Medicamentos , Fibroblastos/metabolismo , Camundongos , Rubídio/metabolismo , Sódio/farmacologia , Transfecção , Vanadatos/farmacologia
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