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1.
Earths Future ; 9(12): e2021EF002285, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35864860

RESUMO

Numerical models for tides, storm surge, and wave runup have demonstrated ability to accurately define spatially varying flood surfaces. However these models are typically too computationally expensive to dynamically simulate the full parameter space of future oceanographic, atmospheric, and hydrologic conditions that will constructively compound in the nearshore to cause both extreme event and nuisance flooding during the 21st century. A surrogate modeling framework of waves, winds, and tides is developed in this study to efficiently predict spatially varying nearshore and estuarine water levels contingent on any combination of offshore forcing conditions. The surrogate models are coupled with a time-dependent stochastic climate emulator that provides efficient downscaling for hypothetical iterations of offshore conditions. Together, the hybrid statistical-dynamical framework can assess present day and future coastal flood risk, including the chronological characteristics of individual flood and wave-induced dune overtopping events and their changes into the future. The framework is demonstrated at Naval Base Coronado in San Diego, CA, utilizing the regional Coastal Storm Modeling System (CoSMoS; composed of Delft3D and XBeach) as the dynamic simulator and Gaussian process regression as the surrogate modeling tool. Validation of the framework uses both in-situ tide gauge observations within San Diego Bay, and a nearshore cross-shore array deployment of pressure sensors in the open beach surf zone. The framework reveals the relative influence of large-scale climate variability on future coastal flood resilience metrics relevant to the management of an open coast artificial berm, as well as the stochastic nature of future total water levels.

2.
Mol Ecol ; 24(10): 2379-91, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25846956

RESUMO

Host shifts are a key mechanism of parasite evolution and responsible for the emergence of many economically important pathogens. Varroa destructor has been a major factor in global honeybee (Apis mellifera) declines since shifting hosts from the Asian honeybee (Apis cerana) > 50 years ago. Until recently, only two haplotypes of V. destructor (Korea and Japan) had successfully host shifted to A. mellifera. In 2008, the sister species V. jacobsoni was found for the first time parasitizing A. mellifera in Papua New Guinea (PNG). This recent host shift presents a serious threat to world apiculture but also provides the opportunity to examine host shifting in this system. We used 12 microsatellites to compare genetic variation of V. jacobsoni on A. mellifera in PNG with mites on A. cerana in both PNG and surrounding regions. We identified two distinct lineages of V. jacobsoni reproducing on A. mellifera in PNG. Our analysis indicated independent host shift events have occurred through small numbers of mites shifting from local A. cerana populations. Additional lineages were found in the neighbouring Papua and Solomon Islands that had partially host shifted to A. mellifera, that is producing immature offspring on drone brood only. These mites were likely in transition to full colonization of A. mellifera. Significant population structure between mites on the different hosts suggested host shifted V. jacobsoni populations may not still reproduce on A. cerana, although limited gene flow may exist. Our studies provide further insight into parasite host shift evolution and help characterize this new Varroa mite threat to A. mellifera worldwide.


Assuntos
Abelhas/parasitologia , Variação Genética , Especificidade de Hospedeiro , Varroidae/genética , Animais , Teorema de Bayes , Fluxo Gênico , Genética Populacional , Haplótipos , Interações Hospedeiro-Parasita/genética , Repetições de Microssatélites , Modelos Genéticos , Papua Nova Guiné , Análise de Sequência de DNA
3.
J Invertebr Pathol ; 118: 71-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24650855

RESUMO

This study has characterised a novel serotype of Sacbrood virus (SBV) infecting Apis mellifera in New Guinea that has emerged in the presence of the introduced European and Asian serotypes, which infect A. mellifera and Apis cerana, respectively. The New Guinea serotype appears to have evolved through mutation of the European serotype with no evidence of recombination between known strains, although recombination was detected in other SBV isolates from Asia. SBV was also confirmed for the first time causing disease in Apis dorsata (giant Asian honeybee) in Indonesia and found to be infected by the Asian serotype.


Assuntos
Abelhas/virologia , Vírus de RNA/genética , RNA Viral/análise , Animais , Sequência de Bases , Dados de Sequência Molecular , Nova Guiné , Filogenia , Sorogrupo
4.
Br J Pharmacol ; 154(7): 1446-56, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18587422

RESUMO

BACKGROUND AND PURPOSE: Drug-induced prolongation of the QT interval can lead to torsade de pointes, a life-threatening ventricular arrhythmia. Finding appropriate assays from among the plethora of options available to predict reliably this serious adverse effect in humans remains a challenging issue for the discovery and development of drugs. The purpose of the present study was to develop and verify a reliable and relatively simple approach for assessing, during preclinical development, the propensity of drugs to prolong the QT interval in humans. EXPERIMENTAL APPROACH: Sixteen marketed drugs from various pharmacological classes with a known incidence -- or lack thereof -- of QT prolongation in humans were examined in hERG (human ether a-go-go-related gene) patch-clamp assay and an anaesthetized guinea-pig assay for QT prolongation using specific protocols. Drug concentrations in perfusates from hERG assays and plasma samples from guinea-pigs were determined using liquid chromatography-mass spectrometry. KEY RESULTS: Various pharmacological agents that inhibit hERG currents prolong the QT interval in anaesthetized guinea-pigs in a manner similar to that seen in humans and at comparable drug exposures. Several compounds not associated with QT prolongation in humans failed to prolong the QT interval in this model. CONCLUSIONS AND IMPLICATIONS: Analysis of hERG inhibitory potency in conjunction with drug exposures and QT interval measurements in anaesthetized guinea-pigs can reliably predict, during preclinical drug development, the risk of human QT prolongation. A strategy is proposed for mitigating the risk of QT prolongation of new chemical entities during early lead optimization.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Síndrome do QT Longo/induzido quimicamente , Animais , Cromatografia Líquida , Desenho de Fármacos , Eletrocardiografia , Canais de Potássio Éter-A-Go-Go/metabolismo , Cobaias , Humanos , Espectrometria de Massas , Modelos Animais , Técnicas de Patch-Clamp
5.
J Microsc ; 213(2): 172-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14731300

RESUMO

Stretching of DNA molecules helps to resolve detail during the fluorescence microscopy of both single DNA molecules and single DNA-protein complexes. To make stretching occur, intricate procedures of specimen preparation and manipulation have been developed in previous studies. By contrast, the present study demonstrates that conventional procedures of specimen preparation cause DNA stretching to occur, if the specimen is the double-stranded DNA genome of bacteriophage phi29. Necessary for this stretching is a protein covalently bound at both 5' termini of phi29 DNA molecules. Some DNA molecules are attached to a cover glass only at the two ends. Others are attached at one end only with the other end free in solution. The extent of stretching varies from approximately 50% overstretched to approximately 50% understretched. The understretched DNA molecules are internally mobile to a variable extent. In addition to stretching, some phi29 DNA molecules also undergo assembly to form both linear and branched concatemers observed by single-molecule fluorescence microscopy. The assembly also requires the terminal protein. The stretched DNA molecules are potentially useful for observing DNA biochemistry at the single molecule level.


Assuntos
Fagos Bacilares/metabolismo , DNA Viral/química , DNA Viral/ultraestrutura , Proteínas de Ligação a DNA/farmacologia , Proteínas Estruturais Virais/farmacologia , Fagos Bacilares/genética , DNA Concatenado/química , DNA Concatenado/ultraestrutura , Proteínas de Ligação a DNA/metabolismo , Microscopia de Fluorescência , Proteínas Estruturais Virais/metabolismo
6.
J Anim Sci ; 80(12): 3179-83, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12542158

RESUMO

One hundred and forty-four pigs were used to determine the effects of a putative synthetic maternal pheromone on behavior and performance of weanling pigs. Each pen of weaned pigs contained three pigs that were given free access to water and feed. Pigs were videotaped in time lapse for 48 h after weaning and weekly body weights and feed disappearances were recorded for 4 wk. Treatments included: a) control (vehicle applied), b) 30 mL of synthetic pheromone applied to the feeder, or c) 10 mL of synthetic pheromone applied to each of three pigs' snouts. Pigs exposed to the synthetic pheromone spent more (P < 0.05) time with their heads in the feeder and less (P < 0.05) time drinking, lying down, or engaged in agonistic behaviors than control pigs. Pigs exposed to the synthetic pheromone were more (P < 0.05) active during the 48-h period of video taping than control pigs. Pigs exposed to the synthetic pheromone (either on the feeder or their snout) had increased (P < 0.01) average daily gain (ADG) and better (P < 0.01) feed:gain ratio than control pigs over the 28-d postweaning period. In conclusion, the putative synthetic pheromone, applied once at weaning, stimulated apparent feeding behaviors, and reduced fighting and apparent drinking behaviors during the first 48 h after weaning. ADG and feed:gain ratio were improved by application of the putative synthetic pheromone either directly on the feeder or when painted on the pigs' snouts. Olfactory signals can modulate adaptation to the postweaning environment in ways that may improve pig performance and welfare.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Feromônios/farmacologia , Suínos/fisiologia , Aumento de Peso/efeitos dos fármacos , Animais , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Distribuição Aleatória , Fatores de Tempo , Gravação em Vídeo , Desmame , Aumento de Peso/fisiologia
7.
Nature ; 413(6857): 748-52, 2001 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-11607035

RESUMO

As part of the viral infection cycle, viruses must package their newly replicated genomes for delivery to other host cells. Bacteriophage straight phi29 packages its 6.6-microm long, double-stranded DNA into a 42 x 54 nm capsid by means of a portal complex that hydrolyses ATP. This process is remarkable because entropic, electrostatic and bending energies of the DNA must be overcome to package the DNA to near-crystalline density. Here we use optical tweezers to pull on single DNA molecules as they are packaged, thus demonstrating that the portal complex is a force-generating motor. This motor can work against loads of up to 57 pN on average, making it one of the strongest molecular motors reported to date. Movements of over 5 microm are observed, indicating high processivity. Pauses and slips also occur, particularly at higher forces. We establish the force-velocity relationship of the motor and find that the rate-limiting step of the motor's cycle is force dependent even at low loads. Notably, the packaging rate decreases as the prohead is filled, indicating that an internal force builds up to approximately 50 pN owing to DNA confinement. Our data suggest that this force may be available for initiating the ejection of the DNA from the capsid during infection.


Assuntos
Fagos Bacilares/genética , DNA Viral/metabolismo , Montagem de Vírus/fisiologia , Fenômenos Biomecânicos , Microesferas , Modelos Genéticos , Óptica e Fotônica
8.
J Urol ; 166(4): 1539-48, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11547128

RESUMO

PURPOSE: Varying the concentration of infused acetic acid produced bladder irritation and dose dependent increases in external urethral sphincter electromyography activity in cats. We further characterized acetic acid induced external urethral sphincter electromyography activity in intact and acute spinal cord injured animals. MATERIALS AND METHODS: Bladder cystometrography and external urethral sphincter electromyography were continuously recorded in chloralose anesthetized cats. Dilute 0.05% to 0.8% acetic acid was infused into the lower urinary tract through the bladder dome. Intravesical or intraurethral infusion was performed separately in bladder neck ligated preparations. In some animals the spinal cord was transected at L1 to L2 2 to 8 hours before the study. RESULTS: Acetic acid infusion into the lower urinary tract elicited dose dependent increases in tonic external urethral sphincter activity. However, a prolonged infusion of 0.7% to 0.8% acetic acid usually inhibited external urethral sphincter activity. The excitatory external urethral sphincter response was elicited by intraurethral but not by intravesical infusion. This response remained in acute spinal cord injured animals. The inhibition of tonic external urethral sphincter activity during 0.7% to 0.8% acetic acid infusion was observed when there was extreme bladder irritation characterized by continual contractions. Induced tonic external urethral sphincter activity was attenuated by intrathecal administration of prazosin or scopolamine and abolished by hexamethonium. CONCLUSIONS: Acetic acid infusion into the lower urinary tract elicits biphasic external urethral sphincter responses. The early excitatory response is a spinal urethrourethral reflex and the late inhibitory phase results from negative vesicourethral feedback control. Spinal muscarinic cholinergic and alpha-adrenergic receptors are involved in acetic acid induced excitatory external urethral sphincter responses.


Assuntos
Ácido Acético/farmacologia , Uretra/efeitos dos fármacos , Uretra/fisiopatologia , Administração Intravesical , Anestesia , Animais , Gatos , Relação Dose-Resposta a Droga , Eletromiografia , Traumatismos da Medula Espinal/fisiopatologia
9.
J Struct Biol ; 135(1): 38-46, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11562164

RESUMO

A method has been developed for three-dimensional image reconstruction of symmetry-mismatched components in tailed phages. Although the method described here addresses the specific case where differing symmetry axes are coincident, the method is more generally applicable, for instance, to the reconstruction of images of viral particles that deviate from icosahedral symmetry. Particles are initially oriented according to their dominant symmetry, thus reducing the search space for determining the orientation of the less dominant, symmetry-mismatched component. This procedure produced an improved reconstruction of the sixfold-symmetric tail assembly that is attached to the fivefold-symmetric prolate head of phi29, demonstrating that this method is capable of detecting and reconstructing an object that included a symmetry mismatch. A reconstruction of phi29 prohead particles using the methods described here establishes that the pRNA molecule has fivefold symmetry when attached to the prohead, consistent with its proposed role as a component of the stator in the phi29 DNA packaging motor.


Assuntos
Fagos Bacilares/química , Imageamento Tridimensional/métodos , Proteínas Estruturais Virais/química , Vírion/química , Fagos Bacilares/ultraestrutura , Microscopia Crioeletrônica/métodos , Análise de Fourier , Secções Congeladas , Modelos Estruturais , Rotação , Vírion/ultraestrutura , Montagem de Vírus
10.
Science ; 293(5537): 2016-8, 2001 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11557870
11.
Arthritis Rheum ; 45(4): 317-23, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11501718

RESUMO

OBJECTIVE: To develop a valid and reliable clinical instrument for measuring pain in adult patients with rheumatoid arthritis. The resulting Rheumatoid Arthritis Pain Scale (RAPS) is a quantitative, single-score, self-report 24-item instrument. METHODS: Psychometric evaluation of RAPS was conducted following estimation of content validity and a pilot study. The actual study used a convenience sample of 120 adults, 18 years of age or older, with pain of at least 3 months duration. The setting was a large rheumatology private practice in a metropolitan southwestern city. The gate control and affective motivational theories of pain served as a framework guiding the development of RAPS, which includes items suggestive of the multidimensional pain experience in rheumatoid arthritis. Four subscales, physiological, affective, sensory-discriminative, and cognitive, evaluated numerous pain factors. RESULTS: Findings indicate a high estimate for internal consistency for the total scale and a moderate to high estimate of internal consistency for projected subscales. Data were analyzed using Cronbach's coefficient alpha, Pearson product-moment correlation coefficients, and exploratory factor analysis. Using Cronbach's coefficient alpha, RAPS showed an internal consistency reliability coefficient of 0.92, a strong indicator of reliability. Reliability assessments for the 4 subscales also indicate reliability, with Cronbach's coefficients ranging from 0.65 to 0.86. Exploratory factor analysis yielded 3 factors with criteria for factor loadings > or = 0.4. CONCLUSION: The study's findings provided support for RAPS as a reliable and valid measurement of rheumatoid arthritis pain. Assessment of rheumatoid arthritis pain and its relationship to treatment outcomes could significantly impact the treatment interventions.


Assuntos
Artrite Reumatoide/fisiopatologia , Medição da Dor/métodos , Inquéritos e Questionários , Adulto , Artrite Reumatoide/psicologia , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Estatística como Assunto
12.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 9): 1260-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11526317

RESUMO

The head-tail connector of bacteriophage phi29 is composed of 12 36 kDa subunits with 12-fold symmetry. It is the central component of a rotary motor that packages the genomic dsDNA into preformed proheads. This motor consists of the head-tail connector, surrounded by a phi29-encoded, 174-base, RNA and a viral ATPase protein, both of which have fivefold symmetry in three-dimensional cryo-electron microscopy reconstructions. DNA is translocated into the prohead through a 36 A diameter pore in the center of the connector, where the DNA takes the role of a motor spindle. The helical nature of the DNA allows the rotational action of the connector to be transformed into a linear translation of the DNA. The crystal structure determination of connector crystals in space group C2 was initiated by molecular replacement, using an approximately 20 A resolution model derived from cryo-electron microscopy. The model phases were extended to 3.5 A resolution using 12-fold non-crystallographic symmetry averaging and solvent flattening. Although this electron density was not interpretable, the phases were adequate to locate the position of 24 mercury sites of a thimerosal heavy-atom derivative. The resultant 3.2 A single isomorphous replacement phases were improved using density modification, producing an interpretable electron-density map. The crystallographically refined structure was used as a molecular-replacement model to solve the structures of two other crystal forms of the connector molecule. One of these was in the same space group and almost isomorphous, whereas the other was in space group P2(1)2(1)2. The structural differences between the oligomeric connector molecules in the three crystal forms and between different monomers within each crystal show that the structure is relatively flexible, particularly in the protruding domain at the wide end of the connector. This domain probably acts as a bearing, allowing the connector to rotate within the pentagonal portal of the prohead during DNA packaging.


Assuntos
Fagos Bacilares/química , Proteínas do Capsídeo , Capsídeo/química , Cristalização , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica
13.
Pediatr Pulmonol ; 31(6): 443-50, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11389577

RESUMO

There is a growing population of adults with cystic fibrosis (CF) and a need for development of adult CF programs. Recommendations for transfer of patients to an adult program include a transition program. Our goal was to assess the current status of transition programs in US CF centers. In addition, we sought to determine the problems related to the transfer of patients to adult programs as perceived by CF center program directors. A survey was sent in 1998 to 110 pediatric and 44 adult program directors at CF centers approved by the Cystic Fibrosis Foundation (CFF), with a response rate of 65.5% and 72.7%, respectively: 22.2% of pediatric centers reported having a non-CFF-approved adult program, and 38.9% had no specific adult program. About one fifth of pediatric centers cited lack of an adult CF physician as an impediment to establishing an adult program. Age (82% of programs; mean, 18.5 years), but not marriage (17.1%) or pregnancy (24.8%), was used as a criterion for transfer. Criteria precluding transfer included patient/family resistance (51.4%), disease severity (50.5%), and developmental delay (46.7%). The concept of transfer is introduced to the patient and family at the time of diagnosis in a minority (14%) of programs. Over one half of the patients did not meet the adult team until the time of transfer. Pediatricians reported higher perceived parent, patient, pediatric staff, and adult staff concerns about transition issues than did adult program directors. We conclude that there is a lack of standardized programs for transfer of CF patients from a pediatric to an adult care setting, and that there are differences between pediatric and adult program directors' perceptions of concerns that CF patients, their families, and the medical teams have about transfer. These differences may impede the successful transition of patients into an adult program.


Assuntos
Instituições de Assistência Ambulatorial , Atitude do Pessoal de Saúde , Continuidade da Assistência ao Paciente , Fibrose Cística/terapia , Transferência de Pacientes , Adolescente , Adulto , Fatores Etários , Criança , Saúde da Família , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pediatria , Encaminhamento e Consulta
14.
Contemp Top Lab Anim Sci ; 40(3): 21-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11353520

RESUMO

Studies were initiated to determine the effects of restricted (32.2 cm2 per mouse), normal (96.8 cm2), or excess floor space (129.0 cm2) allowances by using a model of three mice per cage. BALB/cJ mice were bred on-site and weaned at 3 weeks of age into specially designed polycarbonate shoebox cages modified to each space allowance. Cages contained aspen shavings for bedding, and mice were fed and watered ad libitum. Body weight gains, feed and water use, and immunologic measures largely were not effected by floor space allowances. Female BALB/cJ mice were heavier and had increased lymphocyte blastogenesis to phytohemagglutinin (20 microg/mL) when given 32.2 cm2/mouse than when given 129 cm2/mouse. Female mice showed an increase in grooming and sitting behaviors when given 32.2 cm2/mouse, but male mice with restricted floor space spent more time lying down but showed no change in grooming or sitting behaviors compared to mice given more space. Among male mice, limited floor space did not significantly influence growth rates, but male mice given 32.2 cm2/mouse had less mortality than did mice given more space. We conclude that floor spaces as limited as 32.2 cm2/mouse did not cause behavior, health, immune or performance problems for BALB/cJ mice.


Assuntos
Comportamento Animal/fisiologia , Abrigo para Animais/normas , Camundongos Endogâmicos BALB C/fisiologia , Animais , Peso Corporal/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Camundongos Endogâmicos BALB C/psicologia , Fatores Sexuais , Gravação de Videoteipe
15.
Chest ; 119(4): 1079-84, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11296173

RESUMO

STUDY OBJECTIVES: The purpose of this study is to assess the psychological profiles of adult patients with cystic fibrosis (CF) and to investigate predictors of patients' psychological status. PATIENTS AND METHODS: Thirty-four adults with CF completed a battery of psychological testing including the Minnesota Multiphasic Personality Inventory-2, Beck Depression Inventory, and State-Trait Anxiety inventory. These were compared to health status data, including pulmonary function testing and nutritional status measures. RESULTS: As a group, adults with CF did not demonstrate significant levels of depression, anxiety, or other psychopathology. Results were not affected by age, sex, or severity of disease. Male gender predicted higher scores for depression and anxiety, and better lung functioning predicted less anxiety. Having a higher level of psychosocial support emerged as a strong predictor of better psychological functioning. CONCLUSIONS: Overall, adults with CF report relatively healthy psychological functioning. Better lung function and a strong social support system predicted better psychological functioning, which may have implications for clinical intervention.


Assuntos
Fibrose Cística/psicologia , Adolescente , Adulto , Ansiedade/complicações , Ansiedade/diagnóstico , Atitude Frente a Saúde , Fibrose Cística/fisiopatologia , Depressão/complicações , Depressão/diagnóstico , Feminino , Volume Expiratório Forçado , Nível de Saúde , Humanos , Controle Interno-Externo , Masculino , Pessoa de Meia-Idade , Determinação da Personalidade , Testes Psicológicos , Apoio Social , Capacidade Vital
16.
Am J Physiol Heart Circ Physiol ; 280(2): H830-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158983

RESUMO

The specific Na(+)/H(+) exchange inhibitor HOE-642 prevents ischemic and reperfusion injury in the myocardium. Although this inhibitor alters H(+) ion flux during reperfusion in vitro, this action has not been confirmed during complex conditions in situ. Myocardial intracellular pH (pH(i)) and high-energy phosphates were monitored using (31)P magnetic resonance spectroscopy in open-chest pigs supported by cardiopulmonary bypass during 10 min of ischemia and reperfusion. Intravenous HOE-642 (2 mg/kg; n = 8) administered before ischemia prevented the increases in diastolic stiffness noted in control pigs (n = 8), although it did not alter the postischemic peak-elastance or pressure-rate product measured using a distensible balloon within the left ventricle. HOE-642 induced no change in pH(i) during ischemia but caused significant delays in intracellular realkalinization during reperfusion. HOE-642 did not alter phosphocreatine depletion and repletion but did improve ATP preservation. Na(+)/H(+) exchange inhibition through HOE-642 delays intracellular alkalinization in the myocardium in situ during reperfusion in association with improved diastolic function and high-energy phosphate preservation.


Assuntos
Antiarrítmicos/farmacologia , Diástole/efeitos dos fármacos , Guanidinas/farmacologia , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Sulfonas/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Diástole/fisiologia , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Espectroscopia de Ressonância Magnética , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/fisiopatologia , Prótons , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Suínos
17.
Mol Microbiol ; 39(1): 26-36, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11123685

RESUMO

Plasmodium falciparum is a protozoan parasite responsible for the most severe forms of human malaria. All the clinical symptoms and pathological changes seen during human infection are caused by the asexual blood stages of Plasmodium. Within host red blood cells, the parasite undergoes enormous developmental changes during its maturation. In order to analyse the expression of genes during intraerythrocytic development, DNA microarrays were constructed and probed with stage-specific cDNA. Developmental upregulation of specific mRNAs was found to cluster into functional groups and revealed a co-ordinated programme of gene expression. Those involved in protein synthesis (ribosomal proteins, translation factors) peaked early in development, followed by those involved in metabolism, most dramatically glycolysis genes. Adhesion/invasion genes were turned on later in the maturation process. At the end of intraerythrocytic development (late schizogony), there was a general shut-off of gene expression, although a small set of genes, including a number of protein kinases, were turned on at this stage. Nearly all genes showed some regulation over the course of development. A handful of genes remained constant and should be useful for normalizing mRNA levels between stages. These data will facilitate functional analysis of the P. falciparum genome and will help to identify genes with a critical role in parasite progression and multiplication in the human host.


Assuntos
Eritrócitos/parasitologia , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Plasmodium falciparum/genética , Animais , Moléculas de Adesão Celular/genética , Análise por Conglomerados , Citoesqueleto/genética , Glicólise/genética , Humanos , Plasmodium falciparum/patogenicidade , Biossíntese de Proteínas/genética
18.
Exp Appl Acarol ; 24(3): 165-89, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11108385

RESUMO

Varroa jacobsoni was first described as a natural ectoparasitic mite of the Eastern honeybee (Apis cerana) throughout Asia. It later switched host to the Western honeybee (A. mellifera) and has now become a serious pest of that bee worldwide. The studies reported here on genotypic, phenotypic and reproductive variation among V. jacobsoni infesting A. cerana throughout Asia demonstrate that V. jacobsoni is a complex of at least two different species. In a new classification V. jacobsoni is here redefined as encompassing nine haplotypes (mites with distinct mtDNA CO-I gene sequences) that infest A. cerana in the Malaysia Indonesia region. Included is a Java haplotype, specimens of which were used to first describe V. jacobsoni at the beginning of this century. A new name, V. destructor n. sp., is given to six haplotypes that infest A. cerana on mainland Asia. Adult females of V. destructor are significantly larger and less spherical in shape than females of V. jacobsoni and they are also reproductively isolated from females of V. jacobsoni. The taxonomic positions of a further three unique haplotypes that infest A. cerana in the Philippines is uncertain and requires further study. Other studies reported here also show that only two of the 18 different haplotypes concealed within the complex of mites infesting A. cerana have become pests of A. mellifera worldwide. Both belong to V. destructor, and they are not V. jacobsoni. The most common is a Korea haplotype, so-called because it was also found parasitizing A. cerana in South Korea. It was identified on A. mellifera in Europe, the Middle East, Africa, Asia, and the Americas. Less common is a Japan/Thailand haplotype, so-called because it was also found parasitizing A. cerana in Japan and Thailand. It was identified on A. mellifera in Japan, Thailand and the Americas. Our results imply that the findings of past research on V. jacobsoni are applicable mostly to V. destructor. Our results will also influence quarantine protocols for bee mites, and may present new strategies for mite control.


Assuntos
Abelhas/parasitologia , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Ácaros/classificação , Ácaros/genética , Animais , Ásia , Sequência de Bases , Feminino , Haplótipos , Infestações por Ácaros , Ácaros/anatomia & histologia , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
19.
Perfusion ; 15(6): 549-52, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11131220

RESUMO

A 34-year-old male diagnosed with pseudomyxoma peritoneii presented for an exploratory laparotomy and hyperthermic intraoperative intraperitoneal chemotherapy. A circuit using two roller pumps and a cardioplegia administration set was assembled to deliver the chemotherapy perfusate at a consistent temperature. The authors discuss a case in which this treatment modality was used, describing the perfusionist's role and the circuit design.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma/tratamento farmacológico , Carcinoma/cirurgia , Hipertermia Induzida/métodos , Infusões Parenterais/instrumentação , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/cirurgia , Sarcoma/tratamento farmacológico , Sarcoma/cirurgia , Adulto , Terapia Combinada , Humanos , Hipertermia Induzida/instrumentação , Infusões Parenterais/métodos , Cuidados Intraoperatórios/instrumentação , Cuidados Intraoperatórios/métodos , Masculino , Omento/patologia , Neoplasias Peritoneais/patologia , Neoplasias Esplênicas/tratamento farmacológico , Neoplasias Esplênicas/secundário , Neoplasias Esplênicas/cirurgia
20.
Nature ; 408(6813): 745-50, 2000 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11130079

RESUMO

Motors generating mechanical force, powered by the hydrolysis of ATP, translocate double-stranded DNA into preformed capsids (proheads) of bacterial viruses and certain animal viruses. Here we describe the motor that packages the double-stranded DNA of the Bacillus subtilis bacteriophage phi29 into a precursor capsid. We determined the structure of the head-tail connector--the central component of the phi29 DNA packaging motor--to 3.2 A resolution by means of X-ray crystallography. We then fitted the connector into the electron densities of the prohead and of the partially packaged prohead as determined using cryo-electron microscopy and image reconstruction analysis. Our results suggest that the prohead plus dodecameric connector, prohead RNA, viral ATPase and DNA comprise a rotary motor with the head-prohead RNA-ATPase complex acting as a stator, the DNA acting as a spindle, and the connector as a ball-race. The helical nature of the DNA converts the rotary action of the connector into translation of the DNA.


Assuntos
Fagos Bacilares/química , DNA Viral/química , Proteínas Motores Moleculares/química , Adenosina Trifosfatases/química , Fagos Bacilares/genética , Fagos Bacilares/metabolismo , Capsídeo/química , Capsídeo/metabolismo , Microscopia Crioeletrônica , Cristalografia por Raios X , DNA Viral/metabolismo , Modelos Moleculares , Proteínas Motores Moleculares/metabolismo , Conformação de Ácido Nucleico , RNA Viral/química
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