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Salmonella Give is a rare serotype across Europe. In October 2016, a national outbreak of S. Give occurred in Malta. We describe the epidemiological, environmental, microbiological and veterinary investigations. Whole-genome sequencing (WGS) was performed on human, food, environmental and veterinary isolates. Thirty-six human cases were reported between October and November 2016, 10 (28%) of whom required hospitalisation. Twenty-six (72%) cases were linked to four restaurants. S. Give was isolated from ready-to-eat antipasti served by three restaurants which were all supplied by the same local food manufacturer. Food-trace-back investigations identified S. Give in packaged bean dips, ham, pork and an asymptomatic food handler at the manufacturer; inspections found inadequate separation between raw and ready-to-eat food during processing. WGS indicated two genetically distinguishable strains of S. Give with two distinct clusters identified; one cluster linked to the local food manufacturer and a second linked to veterinary samples. Epidemiological, environmental and WGS evidence pointed towards cross-contamination of raw and ready-to-eat foods at the local manufacturer as the likely source of one cluster. Severity of illness indicates a high virulence of this specific serotype. To prevent future cases and outbreaks, adherence to food safety practices at manufacturing level need to be reinforced.
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Surtos de Doenças , Indústria Alimentícia , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Galinhas/microbiologia , Fabaceae/microbiologia , Fezes/microbiologia , Feminino , Mãos/microbiologia , Humanos , Entrevistas como Assunto , Masculino , Malta/epidemiologia , Carne/microbiologia , Pessoa de Meia-Idade , Olea/microbiologia , Restaurantes , Salmonella/classificação , Intoxicação Alimentar por Salmonella/etiologia , Inquéritos e Questionários , Suínos , Adulto JovemRESUMO
AIMS: To investigate the microbiological quality of imported fresh leaves on retail sale during 2017 with respect to Salmonella, Shiga-toxin-producing Escherichia coli (STEC) and levels of E. coli. METHODS AND RESULTS: Two hundred and seventy-nine samples of imported edible leaves (69 banana, 77 betel, 118 curry and 15 other types) were tested. Salmonella spp. were confirmed by whole-genome sequencing and isolated from 44 samples, 26% from curry leaves, 14% from betel and 2·4% from all other leaf types: 80% of all samples contained ≥102 , 44% ≥103 and 22% ≥104 CFU of E. coli CFU per g. All samples where Salmonella were detected also yielded ≥20 CFU of E. coli/g. 54 samples were tested for STEC which was detected in six samples and isolated from three: one was identified as STEC O157:H7. CONCLUSIONS: This report further highlights an ongoing problem of Salmonella contamination of imported fresh edible leaves. SIGNIFICANCE AND IMPACT OF THE STUDY: Among all food tested by Public Health England (approximately 11 000 per annum), curry leaves were the herb most commonly contaminated with Salmonella, and betel leaves were the most commonly contaminated ready-to-eat food. The high proportion with unsatisfactory E. coli levels and the detection of STEC suggests risks of contamination by multiple enteric pathogens.
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Areca/microbiologia , Helichrysum/microbiologia , Folhas de Planta/microbiologia , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento , Especiarias/microbiologia , Inglaterra , Contaminação de Alimentos/análise , Contaminação de Alimentos/economia , Salmonella/genética , Salmonella/crescimento & desenvolvimento , Salmonella/isolamento & purificação , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Especiarias/economiaRESUMO
The non-conventional yeast Kluyveromyces marxianus is an emerging industrial producer for many biotechnological processes. Here, we show the application of a biomass-linked stoichiometric model of central metabolism that is experimentally validated, and mass and charge balanced for assessing the carbon conversion efficiency of wild type and modified K. marxianus. Pairs of substrates (lactose, glucose, inulin, xylose) and products (ethanol, acetate, lactate, glycerol, ethyl acetate, succinate, glutamate, phenylethanol and phenylalanine) are examined by various modelling and optimisation methods. Our model reveals the organism's potential for industrial application and metabolic engineering. Modelling results imply that the aeration regime can be used as a tool to optimise product yield and flux distribution in K. marxianus. Also rebalancing NADH and NADPH utilisation can be used to improve the efficiency of substrate conversion. Xylose is identified as a biotechnologically promising substrate for K. marxianus.
Assuntos
Microbiologia Industrial , Kluyveromyces/metabolismo , Acetatos/metabolismo , Biomassa , Calibragem , Meios de Cultura/química , Etanol/metabolismo , Glucose/química , Ácido Glutâmico/metabolismo , Glicerol/metabolismo , Inulina/química , Kluyveromyces/genética , Lactatos/metabolismo , Lactose/química , Engenharia Metabólica , Modelos Moleculares , Consumo de Oxigênio , Fenilalanina/metabolismo , Álcool Feniletílico/metabolismo , Reprodutibilidade dos Testes , Ácido Succínico/metabolismo , Xilose/químicaRESUMO
PURPOSE: The tooth-knuckle injury (TKI) is a serious and potentially costly injury seen in orthopaedic practice. The aim was to conduct a systematic literature review on the factors associated with serious complications and high treatment costs in tooth-knuckle injuries. METHODS: MEDLINE, Scopus and CINAHL were used as the literature sources. INCLUSION CRITERIA: Original research papers that reported on factors predicting serious complications and high treatment costs in TKIs were included. There were no restrictions placed on study size, language, study design or date of publication. EXCLUSION CRITERIA: Case studies, case series and review articles were not included. RESULTS: After duplicates were removed, 403 unique studies remained; after titles and abstracts were screened, 48 titles remained and were retrieved in full text. Of these, 14 titles met the inclusion criteria and were included in the data synthesis. Tenosynovitis, septic arthritis, osteomyelitis and residual stiffness were common serious complications occurring in up to 36.3, 70.0, 47.6 and 65.3 % of cases, respectively. Amputation was also common in up to 18.0 % of injuries. Treatment costs were measured by length of hospital stay and the number of debridements required. On average, patients required 3.8-8 days of admission and 1.3-2.7 debridements each. CONCLUSION: Increased time delay from injury to treatment, deeply penetrating injuries, proximal interphalangeal joint (PIPJ) injuries and, possibly, E. corrodens infections were associated with serious complications in TKIs. Delayed treatment, inadequate treatment, PIPJ injuries and deeply penetrating injuries predicted higher treatment costs. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42016029949 ( http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42016029949 ).
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Traumatismos dos Dedos/terapia , Custos de Cuidados de Saúde , Artropatias/terapia , Traumatismos dos Tendões/terapia , Ferimentos Penetrantes/terapia , Amputação Cirúrgica , Antibacterianos/uso terapêutico , Desbridamento , Traumatismos dos Dedos/microbiologia , Humanos , Artropatias/microbiologia , Boca/microbiologia , Fatores de Risco , Traumatismos dos Tendões/microbiologia , Traumatismos Dentários , Violência , Ferimentos Penetrantes/microbiologiaRESUMO
In resource limited nations, cancer control is often a lower priority issue creating challenges for the prevention, early diagnosis, and treatment of cancer. Training and education are vital components of efforts to tackle this problem. A 3-day cancer control workshop was conducted at the Lagos State University Teaching Hospital (LASUTH), Nigeria, in 2013. The curriculum included didactic lectures, panel discussions, and interactive sessions on local cancer statistics, preventive strategies, cancer registries, screening and diagnostic options, and treatment approaches with limited resources (chemotherapy, radiotherapy, surgery, and palliative care) and several site-specific (breast, lung, cervical, prostate, and colon) topics. Pre-workshop and post-workshop questionnaires were completed by participants. Eighty-six percent of the 50 workshop participants completed at least one questionnaire. Participants were mainly nurses and physicians (89% of responders), and 40% reported >25 years of practice experience. The more common local needs identified were professional education (65%) and increasing public cancer awareness (63%). The greatest interest for future programs was on research collaborations (70%). An immediate impact of the workshop was the commencement of monthly tumor board conferences and a review of the current cancer registry data. Capacity building is critical for the execution of effective cancer control strategies. Conducting collaborative workshops represents a cost-effective means of launching programs and energizing the medical community to pursue ongoing education and research addressing the anticipated cancer epidemic on the African continent.
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Promoção da Saúde , Recursos em Saúde , Acessibilidade aos Serviços de Saúde , Oncologia/educação , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Adulto JovemRESUMO
The cockroach ventral nerve cord preparation is a tractable system for neuroethology experiments, neural network modeling, and testing the physiological effects of insecticides. This article describes the scope of cockroach sensory modalities that can be used to assay how an insect nervous system responds to environmental perturbations. Emphasis here is on the escape behavior mediated by cerci to giant fiber transmission in Periplaneta americana. This in situ preparation requires only moderate dissecting skill and electrophysiological expertise to generate reproducible recordings of neuronal activity. Peptides or other chemical reagents can then be applied directly to the nervous system in solution with the physiological saline. Insecticides could also be administered prior to dissection and the escape circuit can serve as a proxy for the excitable state of the central nervous system. In this context the assays described herein would also be useful to researchers interested in limb regeneration and the evolution of nervous system development for which P. americana is an established model organism.
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Sistema Nervoso Central/fisiologia , Sistema Nervoso Central/cirurgia , Rede Nervosa/fisiologia , Periplaneta/fisiologia , Animais , Dissecação/métodos , Estimulação Elétrica , Masculino , Modelos Animais , Células Receptoras Sensoriais/fisiologiaRESUMO
The primary purpose of these procedures is to demonstrate for teaching and research purposes how to record the activity of living primary sensory neurons responsible for proprioception as they are detecting joint position and movement, and muscle tension. Electrical activity from crustacean proprioceptors and tension receptors is recorded by basic neurophysiological instrumentation, and a transducer is used to simultaneously measure force that is generated by stimulating a motor nerve. In addition, we demonstrate how to stain the neurons for a quick assessment of their anatomical arrangement or for permanent fixation. Staining reveals anatomical organization that is representative of chordotonal organs in most crustaceans. Comparing the tension nerve responses to the proprioceptive responses is an effective teaching tool in determining how these sensory neurons are defined functionally and how the anatomy is correlated to the function. Three staining techniques are presented allowing researchers and instructors to choose a method that is ideal for their laboratory.
Assuntos
Extremidades/inervação , Neurofisiologia/educação , Propriocepção/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , CrustáceosRESUMO
We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (C(n)(-), n = 1, 2, 3, 4) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C2 (-) molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s ± 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10(-14) mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity.
RESUMO
BACKGROUND: The adhesive mechanisms regulating leucocyte-endothelium interactions in the pancreas remain elusive, but selectins may play a role. This study examined the molecular mechanisms mediating leucocyte rolling along the endothelium in the pancreas and the therapeutic potential of targeting the rolling adhesive interaction in acute pancreatitis (AP). METHODS: Pancreatitis was induced by retrograde infusion of 5 per cent sodium taurocholate into the pancreatic duct, repeated intraperitoneal administration of caerulein (50 µg/kg) or intraperitoneal administration of L-arginine (4 g/kg) in C57BL/6 mice. A control and a monoclonal antibody against P-selectin were administered before and after induction of AP. Serum and tissue were sampled to assess the severity of pancreatitis, and intravital microscopy was used to study leucocyte rolling. RESULTS: Taurocholate infusion into the pancreatic duct increased the serum level of trypsinogen, trypsinogen activation, pancreatic neutrophil infiltration, macrophage inflammatory protein (MIP) 2 formation and tissue damage. Immunoneutralization of P-selectin decreased the taurocholate-induced increase in serum trypsinogen (median (range) 17·35 (12·20-30·00) versus 1·55 (0·60-15·70) µg/l; P = 0·017), neutrophil accumulation (4·00 (0·75-4·00) versus 0·63 (0-3·25); P = 0·002) and tissue damage, but had no effect on MIP-2 production (14·08 (1·68-33·38) versus 3·70 (0·55-51·80) pg/mg; P = 0·195) or serum trypsinogen activating peptide level (1·10 (0·60-1·60) versus 0·45 (0-1·80) µg/l; P = 0·069). Intravital fluorescence microscopy revealed that anti-P-selectin antibody inhibited leucocyte rolling completely in postcapillary venules of the inflamed pancreas. CONCLUSION: Inhibition of P-selectin protected against pancreatic tissue injury in experimental pancreatitis. Targeting P-selectin may be an effective strategy to ameliorate inflammation in AP.
Assuntos
Migração e Rolagem de Leucócitos/fisiologia , Neutrófilos/fisiologia , Selectina-P/fisiologia , Pancreatite/prevenção & controle , Doença Aguda , Animais , Adesão Celular/fisiologia , Quimiocina CXCL2/metabolismo , Colagogos e Coleréticos/toxicidade , Citocinas/biossíntese , Endotélio/fisiologia , Contagem de Leucócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Selectina-P/antagonistas & inibidores , Pancreatite/induzido quimicamente , Pancreatite/patologia , Peroxidase/metabolismo , Ácido Taurocólico/toxicidade , Tripsinogênio/metabolismoRESUMO
BACKGROUND AND PURPOSE: Severe acute pancreatitis (SAP) is characterized by trypsinogen activation, infiltration of leucocytes and tissue necrosis but the intracellular signalling mechanisms regulating organ injury in the pancreas remain elusive. Rho-kinase is a potent regulator of specific cellular processes effecting several pro-inflammatory activities. Herein, we examined the role of Rho-kinase signalling in acute pancreatitis. EXPERIMENTAL APPROACH: Pancreatitis was induced by infusion of taurocholate into the pancreatic duct in C57BL/6 mice. Animals were treated with a Rho-kinase inhibitor Y-27632 (0.5-5 mg·kg⻹) before induction of pancreatitis. KEY RESULTS: Taurocholate infusion caused a clear-cut increase in blood amylase, pancreatic neutrophil infiltration, acinar cell necrosis and oedema formation in the pancreas. Levels of pancreatic myeloperoxidase (MPO), macrophage inflammatory protein-2 (MIP-2), trypsinogen activation peptide (TAP) and lung MPO were significantly increased, indicating local and systemic disease. Inhibition of Rho-kinase activity dose-dependently protected against pancreatitis. For example, 5 mg·kg⻹ Y-27632 reduced acinar cell necrosis, leucocyte infiltration and pancreatic oedema by 90%, 89% and 58%, respectively, as well as tissue levels of MPO by 75% and MIP-2 by 84%. Moreover, Rho-kinase inhibition decreased lung MPO by 75% and blood amylase by 83%. Pancreatitis-induced TAP levels were reduced by 61% in Y-27632-treated mice. Inhibition of Rho-kinase abolished secretagogue-induced activation of trypsinogen in pancreatic acinar cells in vitro. CONCLUSIONS AND IMPLICATIONS: Our novel data suggest that Rho-kinase signalling plays an important role in acute pancreatitis by regulating trypsinogen activation and subsequent CXC chemokine formation, neutrophil infiltration and tissue injury. Thus, these results indicate that Rho-kinase may constitute a novel target in the management of SAP.
Assuntos
Amidas/farmacologia , Inibidores Enzimáticos/farmacologia , Pancreatite/enzimologia , Pancreatite/patologia , Piridinas/farmacologia , Transdução de Sinais , Tripsinogênio/metabolismo , Quinases Associadas a rho/metabolismo , Amilases/sangue , Animais , Quimiocina CXCL2/metabolismo , Colagogos e Coleréticos/metabolismo , Citometria de Fluxo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Necrose , Infiltração de Neutrófilos , Pâncreas/metabolismo , Pancreatite/induzido quimicamente , Peroxidase/metabolismo , Ácido Taurocólico/metabolismo , Quinases Associadas a rho/antagonistas & inibidoresRESUMO
BACKGROUND: Platelets not only control thrombosis and haemostasis but may also regulate inflammatory processes. Acute pancreatitis (AP) is characterized by changes in both coagulation and proinflammatory activities. The role of platelets in AP is not yet known. METHODS: AP was induced in C57BL/6 mice by repeated caerulein administration (50 µg/kg intraperitoneally). Mice received a platelet-depleting or control antibody before caerulein challenge. Neutrophil infiltration, myeloperoxidase (MPO) and macrophage inflammatory protein (MIP) 2 levels, acinar cell necrosis and haemorrhage in the pancreas, as well as serum amylase activity, were determined 24 h after caerulein injection. In an alternative model of pancreatitis, L-arginine (4 g/kg intraperitoneally) was given twice with an interval of 1 h and tissue samples were taken after 72 h [Correction added after online publication 29 September 2010: in the preceding sentence, 4 mg/kg was corrected to 4 g/kg]. RESULTS: Caerulein administration increased acinar cell necrosis, neutrophil infiltration, focal haemorrhage and serum amylase levels. Platelet depletion reduced acinar cell necrosis, haemorrhage and serum amylase levels in AP. Depletion of platelets decreased caerulein-induced MPO levels and neutrophil recruitment in the pancreas. Platelet depletion abolished caerulein-induced MIP-2 generation in the pancreas and circulation. The effects of platelet depletion on necrosis, neutrophils and MPO levels were confirmed in L-arginine-induced pancreatitis. CONCLUSION: Platelets play a crucial role in AP by regulating neutrophil infiltration, most likely mediated by MIP-2 production in the pancreas.
Assuntos
Plaquetas/fisiologia , Pancreatite/sangue , Amilases/sangue , Animais , Anticorpos/sangue , Arginina/efeitos adversos , Ceruletídeo/efeitos adversos , Quimiocina CXCL2/biossíntese , Quimiocina CXCL2/metabolismo , Citometria de Fluxo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo/fisiologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Peroxidase/metabolismo , Agregação Plaquetária/fisiologia , Complexo Glicoproteico GPIb-IX de Plaquetas/imunologiaRESUMO
We present a case report of a patient with prostate cancer who failed to demonstrate consistent testosterone suppression to castration levels and incomplete suppression of serum prostate-specific antigen, although treated with gonadotropin releasing hormone agonists for 48 months. Serum dehydroepiandrosterone, dehydroepiandrosterone sulphate, as well as the androgen metabolite, androsterone glucuronide, were elevated compared to the other patients. The present data suggest that those prostate cancer patients who have even marginally elevated adrenal androgens may especially benefit from combined androgen blockade.
Assuntos
Adenocarcinoma/sangue , Adenocarcinoma/tratamento farmacológico , Androgênios/sangue , Hormônio Liberador de Gonadotropina/agonistas , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Idoso , Antagonistas de Androgênios/uso terapêutico , Anilidas/uso terapêutico , Busserrelina/uso terapêutico , Diarreia/induzido quimicamente , Flutamida/uso terapêutico , Gastrectomia , Glaucoma/complicações , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/uso terapêutico , Hérnia Hiatal/complicações , Humanos , Hormônio Luteinizante/sangue , Masculino , Nitrilas/uso terapêutico , Úlcera Péptica/complicações , Úlcera Péptica/cirurgia , Antígeno Prostático Específico/sangue , Testosterona/sangue , Compostos de Tosil/uso terapêuticoRESUMO
We propose a computational and theoretical framework for analyzing rapid coevolutionary dynamics of bacteriophage and bacteria in their ecological context. Bacteriophage enter host cells via membrane-bound surface receptors often responsible for nutrient uptake. As such, a selective pressure will exist for the bacteria to modify its receptor configuration and, in turn, for the phage to modify its tail fiber. A mathematical model of these trait adaptations is developed by using the framework of adaptive dynamics. Host strains differ in their efficiency of resource uptake and resistance to phage, whereas phage strains differ in their host preference for adsorption. We solve the evolutionary ecology model and find the conditions for coevolutionary branching and relevant dimensionless parameters leading to distinct quasispecies. We confirm these calculations using stochastic Monte Carlo simulations of populations evolving in a chemostat with fixed washout rate and inflow resource density. We find that multiple quasispecies of bacteria and phage can coexist in a homogeneous medium with a single resource. When diversification occurs, quasispecies of phage adsorb effectively to only a limited subset of the total number of quasispecies of bacteria, i.e., functional differences between quasispecies arise endogenously within the evolutionary ecology framework. Finally, we discuss means to relate predictions of this model to experimental studies in the chemostat, using the model organisms Escherichia coli and the virulent strain of lambda phage.
Assuntos
Adaptação Biológica , Bactérias/virologia , Bacteriófagos , Evolução Biológica , Modelos Biológicos , Bacteriófago lambda , Simulação por Computador , Escherichia coli , Método de Monte CarloRESUMO
In spectrophotometric assays, it has been well established that the recorded absorption, and therefore the experimentally determined extinction coefficient, decreases as a function of detected bandwidth. This manuscript presents an expression for the extinction coefficient as a function of the critical parameter detected bandwidth per transition linewidth. Calculations for both single channel and multichannel photodetection are presented; the derived expressions are shown to be in good agreement with experimental results. It is important to realize that this systematic bias is present in dilute solutions of low absorptivity, and the experimentally recorded extinction coefficient for a molecular standard such as caffeine can vary approximately 4% or more, depending upon choice of research instrumentation. The magnitude of this bias may be sufficient to effect method robustness, cause interlaboratory discrepancies, and fail system suitability requirements for spectrophotometric assays. The signal to noise ratio, for example as analyzed in HPLC/UV-VIS detected chromatograms, is also a function of the detected bandwidths of both the analyte and reference channels. It is shown here that use of a reference can only increase the baseline noise.
Assuntos
Espectrofotometria/instrumentação , Absorção , Algoritmos , Cromatografia Líquida de Alta Pressão , Modelos Teóricos , Reprodutibilidade dos Testes , Espectrofotometria UltravioletaRESUMO
Robust increases in locomotor activity are observed following administration of dizocilpine maleate (MK-801). The present study investigated the effects of prior apparatus experience and manipulation of the testing environment on locomotor activity following peripheral MK-801. Gerbils were given zero or nine sessions of apparatus exposure prior to testing with MK-801 (0.1 mg/kg ip) or saline. Sessions were 10 min in duration and separated by 24 h. As previously reported, naive animals treated with MK-801 were significantly more active relative to controls. Exposure to the apparatus for nine sessions resulted in a significant reduction in MK-801-induced activity, but did not alter the activity levels of control animals. To evaluate the effect of changes to the testing environment, animals previously evaluated in the familiar condition were retested in the identical apparatus relocated to a novel experimental room. MK-801-treated animals exhibited a significant increase in activity when tested in this novel environment while the locomotor activity of control gerbils was not significantly altered. The results illustrate the importance of repetitive testing and environmental changes as moderating variables in studies that evaluate locomotor activity. These data also indicate that the effects of MK-801 on activity are sensitive to prior experience with the apparatus and the novelty of the testing environment.
Assuntos
Maleato de Dizocilpina/farmacologia , Meio Ambiente , Antagonistas de Aminoácidos Excitatórios/farmacologia , Atividade Motora/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Gerbillinae , Habituação Psicofisiológica , Comportamento Estereotipado/efeitos dos fármacosRESUMO
The lifetime of two metastable levels in Fe+ has been measured by laser probing of a stored ion beam. In the dense spectrum of Fe+, the metastable levels a (6)S(5/2) and b (4)D(7/2) were selected and their lifetimes were determined to be 230 +/- 30 and 530 +/- 30 ms, respectively. The lifetimes are compared with previous theoretical results. Metastable lifetime measurements of Fe+ are of great importance for interpretation of spectra from astronomical objects. The present experiment opens for the possibilities to investigate lifetimes of metastable states in complex atomic ions, which have, so far, been unexplored.
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OBJECTIVE: Animal models of hindlimb ischemia are critical to our understanding of peripheral vascular disease and allow us to evaluate therapeutic strategies aimed to improve peripheral collateral circulation. To further elucidate the processes involved in revascularization following ischemia, we evaluated the temporal association between tissue ischemia, vascular endothelial cell growth factor (VEGF) release, angiogenesis (capillary sprouting), arteriogenesis (growth of the larger muscular arteries), and reserve blood flow (functional collateral flow). METHODS: New Zealand White rabbits (male 3-4 kg) were evaluated at specific days (0, 5, 10, 20 or 40) following femoral artery removal for measurement of hindlimb blood flow, skeletal muscle lactate production and VEGF content, capillary density (a marker of angiogenesis), and angiographic score (a marker of arteriogenesis). RESULTS: Maximal capillary sprouting occurred within 5 days of femoral artery removal and was temporally associated with reduced resting hindlimb blood flow, increased lactate release and detectable levels of skeletal muscle VEGF. The growth of larger angiographically visible collateral vessels occurred after 10 days and was not temporally associated with ischemia or skeletal muscle VEGF content, but did coincide with a large functional improvement in the reserve blood flow capacity of the limb. CONCLUSIONS: Following femoral artery removal in the rabbit, the time course of angiogenesis and arteriogenesis were clearly distinct. Tissue ischemia and/or VEGF may stimulate capillary sprouting, but this response does not translate to a significant improvement in collateral flow. The growth and development of the larger collateral vessels was correlated with a large functional improvement in collateral flow, and occurred at a time when VEGF levels were undetectable.
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Circulação Colateral , Membro Posterior/irrigação sanguínea , Isquemia/fisiopatologia , Neovascularização Fisiológica , Doenças Vasculares Periféricas/fisiopatologia , Análise de Variância , Animais , Artérias , Capilares , Fatores de Crescimento Endotelial/metabolismo , Membro Posterior/diagnóstico por imagem , Artéria Ilíaca/fisiopatologia , Isquemia/diagnóstico por imagem , Isquemia/metabolismo , Ácido Láctico/metabolismo , Linfocinas/metabolismo , Masculino , Doenças Vasculares Periféricas/diagnóstico por imagem , Doenças Vasculares Periféricas/metabolismo , Coelhos , Radiografia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
Care pathways have recently been developed for hospice patients who die within one week of admission. This development was motivated by a number of factors. First, under managed care cost constraints, it is sometimes difficult to obtain early hospice admission approval because of certain reimbursement regulations. Second, patient and family wishes change during the illness trajectory as patients move through the stages of death and dying. Third, and most important to the caregiver, is that the philosophy adopted within care pathways advocates that patients should not suffer at the end of life. This article outlines the rationale for the formation of care pathways and describes a care pathway developed for a specific group of patients.
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Procedimentos Clínicos/organização & administração , Cuidados Paliativos na Terminalidade da Vida/organização & administração , Planejamento de Assistência ao Paciente/organização & administração , Atitude do Pessoal de Saúde , California , Humanos , Tempo de Internação , Programas de Assistência Gerenciada/organização & administração , Avaliação das Necessidades , Avaliação de Resultados em Cuidados de Saúde , Admissão do Paciente , Equipe de Assistência ao Paciente/organização & administração , Assistência Centrada no Paciente/organização & administração , Filosofia em Enfermagem , Inquéritos e Questionários , Fatores de TempoRESUMO
In the limbs of crustaceans, proprioception is monitored by chordotonal organs. One in particular, MC1, is arranged in a manner that is accessible for single unit recording of primary sensory neurons while simulating joint movement. The movement-sensitive cells are of two types, those sensitive to relaxation or to elongation of the chordotonal strand which corresponds to flexion or extension of the meropodite-carpopodite joint, respectively. A statistical method for the quantification of these movement-sensitive proprioceptive neuronal responses was implemented. This statistical index, eta(2), should allow neuronal responses recorded in different laboratories to be easily and quantitatively compared. In addition, an eta(2) value can be assigned to individual cells which represents a cell's consistency and degree to which the response is related to the stimulus. We found some cells to have a high eta(2) and to be consistent in their activity while other cells had a high degree of variability with low eta(2) values. J. Exp. Zool. 284:629-636, 1999.
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Braquiúros/fisiologia , Mecanorreceptores/fisiologia , Neurônios Aferentes/fisiologia , Propriocepção/fisiologia , Órgãos dos Sentidos/fisiologia , Potenciais de Ação/fisiologia , Animais , Interpretação Estatística de Dados , Extremidades/fisiologia , Articulações/fisiologia , MasculinoRESUMO
The evolutionary developments that led to the ability of photosynthetic organisms to oxidize water to molecular oxygen are discussed. Two major changes from a more primitive non-oxygen-evolving reaction center are required: a charge-accumulating system and a reaction center pigment with a greater oxidizing potential. Intermediate stages are proposed in which hydrogen peroxide was oxidized by the reaction center, and an intermediate pigment, similar to chlorophyll d, was present.