RESUMO
Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of â¼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.
RESUMO
Poor storage capacity is a major constraint limiting further expansion of the use of entomopathogenic nematodes. In order to prolong shelf life, a quiescent state of the dauer juveniles (DJs) should be induced. This can be attained by means of desiccation of DJs. In this study, 24 natural isolations of Steinernema feltiae were exposed to desiccation stress in non-ionic polyethylene glycol 600. The dehydrating conditions were measured as water activity, a(w)-value. Non-adapted and adapted DJs were tested separately under a series of dehydrating conditions. The mean tolerated a(w)-value (MW50) ranged from 0.85 for the isolate NEP1 to 0.95 for FIN1, ISR5 and ITA2 when not adapted to desiccation stress and from MW50 of 0.822 for CR1 to 0.98 for ISR6 when adapted to the stress conditions. CR1 tolerated the lowest desiccation stress at an a(w)-value for the most tolerant 10% of the population (MW10) at 0.65 when DJs had been adapted to stress. No significant differences were recorded between all isolates in non-adapted DJs populations MW10 was compared. No correlation between tolerance under non-adapted and adapted conditions were found. Most tolerant isolates will now be used for cross-breeding and subsequent genetic selection to enhance desiccation tolerance.
Assuntos
Mariposas/parasitologia , Rabditídios/química , Animais , Desidratação , Controle Biológico de Vetores , Rabditídios/genética , Rabditídios/isolamento & purificação , Rabditídios/metabolismo , Água/metabolismoRESUMO
Most plants, when damaged by herbivore insects, synthesize and release various chemicals as indirect defence mechanism that attract parasitic or predatory insects that are natural enemies of the herbivores. When attacked by Western Corn Rootworms, the roots of many maize plant varieties emit (E)-beta-caryophyllene that attracts the neighbouring entomopathogenic nematodes to kill the feeding pest. Through plant genetics and biotechnology it was possible to manipulate this volatile compound in order to increase the effectiveness of entomopathogenic nematodes in reducing the damage of the pest. In order to further use this strategy to improve the effectiveness of Heterorhabditis bacteriophora by selective breeding, we invesa tigated the applicability of the strategy in different standard laboratory bioassays using three different sand and agar plate assays. The synthetic form of (E)-beta-caryophyllene and H. megidis (the strain, which in previous investigation, showed significant attraction to caryophyllene) were used in the study. In all bioassays no significant difference was observed in attraction of nematodes between the caryophyllene treatments and the controls. The results contradict results of previous investigations done by other investigators (Rasmann et al., 2005). Future investigations for the genetic improvement of the host finding ability of entomopathogenic nematodes can therefore not target attraction to caryophyllene.
Assuntos
Quimiotaxia/efeitos dos fármacos , Besouros/fisiologia , Nematoides/fisiologia , Plantas/química , Sesquiterpenos/farmacologia , Animais , Comportamento Alimentar , Larva , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/químicaRESUMO
Codling moth (CM) is a serious and global pest of pome fruit. It overwinters in cryptic habitats as cocooned diapausing larvae. Field trials with the entomopathogenic nematode Steinernema feltiae (Rhabditida: Steinernematidae) report control of diapausing CM of up to 70%, but results are variable. The objective of this study was to define environmental conditions favouring the performance of the nematodes. Cocooned larvae were more susceptible than non-cocooned larvae. S. feltiae was unable to infect CM at a water activity (aw-values) < or = 0.9. Mortality of cocooned larvae was reported at lower aw-values than of non-cocooned larvae. Exposure time and impact of external relative humidity (RH) was studied. Mortality of cocooned larvae did not further increase after half an hour of exposure, whereas the mortality increased with increasing exposure time in non-cocooned larvae. LC50 and LC90 considerably decreased with increasing RH. The influence of the relative humidity was less pronounced when surpassing 80% than the effect of the volume of applied water. When S. feltiae was formulated in a surfactant-polymer-formulation (SPF), mortality significantly increased when compared to application in water.
Assuntos
Umidade , Mariposas/parasitologia , Nematoides/fisiologia , Animais , Interações Hospedeiro-Parasita , Larva/parasitologia , Controle Biológico de VetoresRESUMO
Four strains of Steinernema feltiae from Eastern Java, Indonesia were characterized based on morphometric, morphological and molecular data. In addition, their virulence against last instar Tenebrio molitor and heat tolerance was tested. Infective juvenile have a mean body length ranging from 749 to 792 microm. The maximum sequence difference among the four strains was 7 bp (8.8%) in the ITS and 2 bp (0.3%) in D2D3 regions of the rDNA. All the strains are not reproductively isolated and can reproduce with European strain S. feltiae Owiplant. The lowest LC50 was observed for strain SCM (373) and the highest for S. feltiae strain Owiplant (458) IJs/40 T. molitor. All four strains showed relatively better mean heat tolerance when compared with S. feltiae Owiplant, both in adapted and non-adapted heat tolerance experiments.
Assuntos
Variação Genética , Nematoides/genética , Animais , Cruzamentos Genéticos , Demografia , Indonésia , Filogenia , Tenebrio/parasitologiaRESUMO
OBJECTIVE: This study aimed to determine the knowledge of first year health sciences students at a South African university regarding hearing loss and symptoms attributable to personal listening devices and their practices concerning the use of personal listening devices. METHOD: This was a cross-sectional study carried out using an anonymous self-administered questionnaire. RESULTS: Of 336 students, 269 (80.1 per cent) completed the questionnaire. While most participants could identify symptoms that could be caused by extensive use of personal listening devices, almost 30 per cent did not know that it could cause permanent hearing loss. Personal listening devices were used by 90.7 per cent of participants, with 77.8 per cent having used them for more than five years. Use was at a high volume in 14.9 per cent of participants and for more than 2 hours per day in 52.7 per cent. CONCLUSION: The findings indicate the need for an educational programme to inform students as to safe listening practices when using personal listening devices.
Assuntos
Perda Auditiva Provocada por Ruído/epidemiologia , Estudantes/psicologia , Adulto , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Percepção Sonora , Masculino , Universidades , Adulto JovemRESUMO
The rhabditid nematodes Steinernema carpocapsae and Steinernema feltiae are used in biological control of insect pests. Mass production is done in liquid culture media pre-incubated with their bacterial symbionts Xenorhabdus nematophila and Xenorhabdus bovienii, respectively, before nematode dauer juveniles (DJs) are inoculated. As a response to food signals produced by the bacterial symbionts, the DJs exit from the developmentally arrested dauer stage (they recover development) and grow to adults, which produce DJ offspring. Variable DJ recovery after inoculation often causes process failure due to non-synchronous population development and low numbers of adult nematodes. This contribution investigated the influence of the bacterial cell density on DJ recovery and development to adults. At higher density of 10(10) bacterial cells ml(-1), a higher percentage of DJ recovery was induced, and adults occurred earlier in both Steinernema spp. than at lower density of 10(9) and 10(8) cells ml(-1). Xenorhabdus symbionts produce phase variants. Recovery in bacteria-free supernatants was lower than in supernatants containing bacterial cells for both primary and secondary phase Xenorhabdus spp. and lower in secondary than in primary phase supernatants or cell suspensions. In general, recovery was lower for Steinernema feltiae and the time at which 50% of the population had recovered after exposure to the food signal was longer (RT(50) = 17.1 h) than for Steinernema carpocapsae (RT(50) = 6.6 h). Whereas >90% S. carpocapsae DJs recovered in hemolymph serum of the lepidopteran insect Galleria mellonella, recovery of S. feltiae only reached 31%. Penetration into a host insect prior to exposure to the insect's food signal did not enhance DJ recovery. Consequences for liquid culture mass production of the nematodes and differences between species of the genera Steinernema and Heterorhabditis are discussed.
Assuntos
Controle Biológico de Vetores , Rabditídios/crescimento & desenvolvimento , Rabditídios/microbiologia , Simbiose , Xenorhabdus/crescimento & desenvolvimento , Animais , Mariposas/crescimento & desenvolvimento , Mariposas/parasitologia , Rabditídios/fisiologia , Xenorhabdus/fisiologiaRESUMO
For commercial use of the entomopathogenic nematodes Steinernema carpocapsae and Steinernema feltiae in biological control of insect pests, they are produced in liquid culture on artificial media pre-incubated with their symbiotic bacteria Xenorhabdus nematophila and Xenorhabdus bovienii, respectively. After 1 day of the bacterial culture, nematode dauer juveniles (DJs) are inoculated, which recover development. The adult nematodes produce DJ offspring, which are harvested and can be sprayed. This study determined optimal temperatures to obtain high DJ progeny within a short process time. Temperatures assessed were 23 degrees C, 25 degrees C, 27 degrees C, and 29 degrees C for S. carpocapsae and 20 degrees C, 23 degrees C, 25 degrees C, and 27 degrees C for S. feltiae. The recovery of inoculated DJs was hardly affected and was reduced only in S. carpocapsae at 29 degrees C. The fecundity (eggs in uterus) in S. carpocapsae reached a maximum at 27 degrees C; whereas, maximum yields were recorded at 25 degrees C. For both Steinernema spp., highest DJ densities were obtained after 15 days incubation at 25 degrees C. Optimal culture temperature for both nematode species is 25 degrees C. S. carpocapsae was more sensible to suboptimal temperature than S. feltiae. Results on total DJ density and DJ proportion of the total nematode population were more variable at non-optimal temperature condition for S. carpocapsae than for S. feltiae. Suboptimal culture temperature also reduced DJ infectivity.
Assuntos
Rabditídios/crescimento & desenvolvimento , Animais , Meios de Cultura , Feminino , Fertilidade , Masculino , Controle Biológico de Vetores/economia , Controle Biológico de Vetores/métodos , Rabditídios/microbiologia , Simbiose , Temperatura , Xenorhabdus/crescimento & desenvolvimentoRESUMO
We link schizophrenia in families from the genetically isolated South African Afrikaner population to chromosome 13q (n =51), 1p (n =23) and combined 13q & 1p (n =18). Patients with linkages to chromosome 13q were 4.16 times more likely to meet diagnostic criteria for schizoaffective disorder compared to patients with linkage to 1p. A third of patients with linkage to both 13q &1p met diagnostic criteria for SAD. There was a significant positive relationship between suicidality and a diagnosis of schizoaffective disorder. Identifying linkage to chromosome 13q may be informative in identifying suicide risk early and prevent morbidity and mortality in schizophrenia patients.
Assuntos
Cromossomos Humanos Par 13 , Ligação Genética , Esquizofrenia/genética , Suicídio/psicologia , Adulto , Feminino , Humanos , Masculino , Risco , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto JovemRESUMO
The diamondback moth (DBM), Plutella xylostella, is a major pest of crucifers and has developed resistance against all chemical insecticides, even against the biological insecticide Bacillus thuringiensis (Bt). Entomopathogenic nematodes (EPN) as novel biological insecticide were successfully used against DBM. We investigated the potential of Bt to enhance the virulence of EPN and the possibility to reduce the application density by exploiting synergistic effects. The interaction between different combinations of Bt and EPN were tested against early 3rd instar P. xylostella on 2 cm2 cabbage leaf discs. All of the combinations had additive effects. Synergistic results were exceptional. The result indicate that a joint application of Bt and EPN is not recommended. But alternating applications are a measure to manage resistance development against Bt.
Assuntos
Bacillus thuringiensis/fisiologia , Mariposas/crescimento & desenvolvimento , Rabditídios/fisiologia , Animais , Brassica/parasitologia , Resistência a Inseticidas , Controle Biológico de Vetores , Folhas de Planta/parasitologiaRESUMO
Genome-wide scans have revealed a significant role for de novo copy number variants (CNVs) and Single Nucleotide variants (SNVs) in the genetic architecture of schizophrenia. The present study attempts to parse schizophrenia based on the presence of such de novo mutations and attempts genotype-phenotype correlation. We examined phenotypic variables across three broad categories: clinical presentation, premorbid function, disease course and functional outcome and compared them in individuals with schizophrenia carrying either a de novo CNV, a de novo SNV, or no de novo mutation. Work skills were worst affected in patients carrying de novo CNVs. More learning disabilities were found in subjects carrying de novo SNVs. Patients with either mutation had older parents at birth and worse functional outcome as measured by SLOF scores. We found no relation between treatment resistance and the presence of de novo mutations. The combined consideration of the functional outcome scores and early deviant behaviours was found to have higher predictive value for underlying genetic vulnerability. Due to the rare nature of the de novo mutations the sample sizes studied here were small. Despite this, valuable phenotypic characteristics were identified in schizophrenia patients carrying de novo mutations and studying larger samples will be of interest.
Assuntos
Variações do Número de Cópias de DNA , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética , Adulto , Idade de Início , Criança , Feminino , Estudos de Associação Genética , Triagem de Portadores Genéticos , Predisposição Genética para Doença/genética , Humanos , Deficiências da Aprendizagem/diagnóstico , Deficiências da Aprendizagem/genética , Masculino , Pessoa de Meia-Idade , Mutação , Projetos Piloto , Prognóstico , Esquizofrenia/diagnóstico , Estatística como AssuntoRESUMO
Patients with acute coronary syndromes (ACS) frequently present with signs of disturbed fibrinolysis. The present study investigates the correlation of alterations in the fibrinolytic system and the amount of myocardial damage characterized by troponin release. In 85 patients with ACS markers of plasmin activation, plasminogen activator system and troponin T (TnT) were measured initially and after 48 h. Patients with TnT release (> or = 0.01 microg/l) at admission had higher TPA levels than those without release (10.2+/-0.7 ng/ml vs. 7.6+/-0.5 ng/ml; p <0.01). Additionally, patients with positive TnT had higher D-dimer levels initially (457+/-39 ng/ml vs. 316+/-22 ng/ml; p <0.01) and 48 h later (451+/-42 ng/ml vs. 275+/-37 ng/ml; p <0.01). The association of myocardial damage with a prothrombotic state and an enhanced fibrinolysis may explain the high prognostic value of troponin measurements in respect to future coronary events.
Assuntos
Doença das Coronárias/sangue , Fibrinólise/fisiologia , Troponina T/metabolismo , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Doença das Coronárias/diagnóstico , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinolisina/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Miocárdio/patologia , Plasminogênio/metabolismo , Prognóstico , Trombofilia/sangue , Trombofilia/complicações , Ativador de Plasminogênio Tecidual/sangue , Troponina T/sangue , Troponina T/fisiologiaRESUMO
BACKGROUND: Neurotensin, an important gut hormone, binds its receptor (NTR) to stimulate proliferation of intestinal cells; the molecular mechanisms remain largely undefined. Mitogen-activated protein kinases (MAPKs) translocate to the nucleus and induce transcription factors (eg, c-Fos) in response to certain trophic agents. The purpose of this study was (1) to define the signaling mechanisms regulating neurotensin and (2) to determine whether the AP-1 transcription factor c-Fos is induced. METHODS: Expression of the NTR gene was determined in the human colon cancer cell lines KM12C, KML4A, and KM20 by Northern blot analysis and ribonuclease-protection experiments. To assess whether NTR was functionally coupled to the CA(2+)-signaling pathway, intracellular CA2+ ([Ca2+]i) mobilization was assessed by fura-2 spectrofluorometry. To determine whether the MAPK signaling pathway was activated in KM20 cells by neurotensin, Western blots for the phosphorylated forms of MAPK (p42 and p44) and in vitro kinase assays were performed. In addition, Western blots were performed to assess levels of c-Fos after neurotensin treatment. RESULTS: The NTR gene was expressed in the KM20 cell line but not in KM12C or KM12LA. The NTR in KM20 cells was functionally coupled to the CA(2+)-signaling pathway as noted by a rapid (30 seconds) mobilization of [Ca2+]i after addition of neurotensin; the neurotensin-mediated response was blocked by the NTR antagonist SR48692. Both p42MAPK and p44MAPK were stimulated by neurotensin approximately 3 to 6 minutes after treatment. Increased levels of c-Fos were demonstrated, with peak levels occurring 2 hours after addition of neurotensin. CONCLUSIONS: Our results demonstrate that neurotensin binds to its endogenous NTR in KM20 cells with stimulation of the Ca(2+)- and MAPK-signaling pathways and an increase in the levels of the AP-1 protein c-Fos. Delineating the signal transduction mechanisms regulating the cellular effects of neurotensin will provide important insights into the molecular pathways responsible for gut hormone-mediated proliferation.
Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Neurotensina/genética , Transdução de Sinais/genética , Northern Blotting , Western Blotting , Cálcio/fisiologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Neoplasias do Colo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neurotensina/metabolismo , Neurotensina/farmacologia , Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/análise , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologiaRESUMO
BACKGROUND: Reactive oxygen species (ROS) have been implicated in the induction of acute pancreatitis. Mitochondria possess a distinct genome (mtDNA) that is more susceptible to ROS-induced damage than nuclear DNA (nDNA). The purpose of our study was to determine the effect of ROS on mitochondrial function and membrane potential (delta psi mt), to identify signal transduction mechanisms activated by ROS, and to quantify damage to mtDNA in an in vitro pancreatitis model. METHODS: Pancreatic acinar cells, AR4-2J, were treated with saline solution (control) or hydrogen peroxide (H2O2), a representative ROS. Mitochondrial function was assessed with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; to determine delta psi mt, rhodamine-123 uptake was measured. Intracellular calcium levels and c-Jun N-terminal kinase activity was determined; gel mobility shift assays were performed to assess induction of the transcription factor NF-kappa B. To quantitate DNA damage, a novel polymerase chain reaction-based procedure was performed. RESULTS: Mitochondrial function and delta psi mt were significantly decreased with oxidative damage. H2O2 treatment resulted in increased intracellular calcium levels, activation of c-Jun N-terminal kinase, and induction of NF-kappa B DNA binding. Treatment of AR4-2J cells with H2O2 resulted in selective mtDNA damage; nDNA was not affected. CONCLUSIONS: Our data demonstrate that pancreatic mtDNA is more susceptible to oxidative damage than nDNA; this damage is associated with decreases in mitochondrial function and delta psi mt and activation of downstream signal transduction pathways. Mitochondrial damage mediated by ROS may play a central role in pancreatic cell injury associated with acute pancreatitis.
Assuntos
Dano ao DNA , DNA Mitocondrial/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Mitocôndrias/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Pâncreas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Cálcio/metabolismo , MAP Quinase Quinase 4 , Potenciais da Membrana , NF-kappa B/metabolismo , Proteínas Quinases/fisiologia , Ratos , Células Tumorais CultivadasRESUMO
Heat shock proteins (HSPs) 70 and 27 are stress-responsive proteins that are important for cell survival after injury; the expression of these HSPs is regulated primarily by the transcription factor heat shock factor-1 (HSF-1). The purpose of this study was to determine the effect of acute pancreatitis on pancreatic HSPs (70, 27, 60, and 90) expression and to assess potential mechanisms for HSP induction using a murine model of cerulein-induced pancreatitis. We found an increase of both HSP70 and HSP27 levels with expression noted throughout the pancreas after induction of pancreatitis. HSP60 and HSP90 levels were constitutively expressed in the pancreas and did not significantly change with acute pancreatitis. HSF-1 DNA binding activity increased in accordance with increased HSP expression. We conclude that acute pancreatitis results in a marked increase in the expression of HSP70 and HSP27. Furthermore, the induction of HSP70 and HSP27 expression was associated with a concomitant increase in HSF-1 binding activity. The increased expression of both HSP70 and HSP27 noted with pancreatic inflammation may confer a protective effect for the remaining acini after acute pancreatitis.
Assuntos
Proteínas de Ligação a DNA/biossíntese , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico , Proteínas de Neoplasias/biossíntese , Pancreatite/metabolismo , Doença Aguda , Animais , Western Blotting , Ceruletídeo , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Eletroforese , Feminino , Fatores de Transcrição de Choque Térmico , Camundongos , Chaperonas Moleculares , Pancreatite/induzido quimicamente , Fatores de TranscriçãoRESUMO
BACKGROUND: Activation of the mitogen-activated protein kinases (MAPKs) appears to play an important role in both proliferation and transformation of various cells; the role of MAPK activation in colorectal cancers has not been clearly defined. The purpose of our study was to determine whether MAPK activity and protein levels were increased in colorectal cancers. METHODS: Colorectal cancers and adjacent normal mucosa from 21 patients were extracted for protein. Expression levels and activity of the MAPKs (ERK1/2, JNK1, p38 and ERK3) were assessed by immunoblot analysis and in vitro kinase assays, respectively. In addition, changes in myelin basic protein (MBP) kinase activity and autophosphorylation were determined by in-gel kinase assays. RESULTS: The activities of ERK1/2, JNK1 and p38 were downregulated in the majority of cancers; ERK3 kinase activity was increased in 10 of 21 cancers. The presence of proteins displaying increased MBP phosphorylation and autophosphorylation was identified specifically in the cancers by in-gel kinase assays. CONCLUSIONS: Our findings demonstrate that the constitutive activation of ERK1/2, JNK1 and p38 is not a feature of colorectal cancers. Moreover, our in-gel kinase results suggest that protein kinases, other than the MAPKs assessed, may play a more crucial role in colon carcinogenesis.
Assuntos
Adenocarcinoma/enzimologia , Neoplasias do Colo/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Proteínas de Neoplasias/biossíntese , Adenocarcinoma/genética , Adenocarcinoma/patologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/biossíntese , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Quinase 3 da Glicogênio Sintase , Humanos , Mucosa Intestinal/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/biossíntese , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno , Proteína Quinase 6 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
Sequence variation within the variable region of the 16S rRNA at position 440 to 480 allowed the synthesis of specific PCR primers for the identification of groups within the species Photorhabdus luminescens, symbionts of entomopathogenic nematodes of the genus Heterorhabditis. For the second PCR primer the highly conserved region at 755 to 795 was used. The P. luminescens type strain specific primer could not recognize any other P. luminescens strain. The primer TEMPERATUS based on the sequence of strain DSM12190 (isolated from North West European H. megidis strain HSH2) identified all P. luminescens associated with H. megidis from North West Europe and two isolates from closely the related nematode strains from Ireland. The primer TROPICUS based on strain DSM12191 (isolated from the nematode type strain H. indica strain LN2) identified P. luminescens of tropical origin isolated from H. indica. Symbionts of H. bacteriophora could not yet be separated into well described groups with the primers used. A comparison of sequence data resulted in the identification of additional groups. The non-symbiotic P. luminescens isolates are distinct in the variable region. The group HELIOTHIDIS contains 15 P. luminescens associated with H. bacteriophora from North East America. The MARELATUS group contains symbionts of the nematode H. marelatus from the West Coast of the US. The data together with the specific symbiotic association of P. luminescens strains with different nematode species support the division of the taxon P. luminescens into different species.
Assuntos
Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Reação em Cadeia da Polimerase/métodos , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Rhabditoidea/microbiologia , Animais , Primers do DNA , Simbiose/fisiologiaRESUMO
Entomopathogenic nematodes can be mass produced in artificial media for use as biological insecticides. Nematode in vitro media have been primarily developed on the basis of yield without fully considering nematode nutritional requirements. We investigated the quality and quantity of lipids in the entomopathogenic nematode Steinernema glaseri when grown in vivo in Popillia japonica (a natural host), Galleria mellonella (a factitious host), and in solid and liquid media. Nematode yield (infective juveniles per mg dry organic material) was 4 times higher in the in vivo compared with the in vitro cultures. Nematodes produced in vivo using P. japonica accumulated a significantly higher amount of lipids compared with nematodes grown using G. mellonella or in vitro solid and liquid methods, respectively. Fractionation of S. glaseri total lipids revealed that nematodes produced using P. japonica accumulated significantly higher phospholipids and sterols compared with other methods. C:18 fatty acids were the predominant class of lipids in S. glaseri irrespective of production method. In vivo-produced nematodes had oleic 18:1 acid as the major fatty acid, whereas in vitro-produced S. glaseri had a mixture of oleic 18:1 and linoleic 18:2 acids as the predominant fatty acids. We conclude that the lipid composition of entomopathogenic nematode is host or medium dependent. We suggest that adjusting the in vivo medium by addition of components similar to a natural host nutritional composition should improve nematode production.
Assuntos
Besouros/parasitologia , Lepidópteros/parasitologia , Lipídeos/análise , Rhabditoidea/química , Rhabditoidea/crescimento & desenvolvimento , Animais , Meios de Cultura , Ácidos Graxos/análise , Lipídeos/químicaRESUMO
In patients with acute myocardial infarction treated with thrombolytics, platelet activation as well as alterations of the hemostatic and fibrinolytic systems have been described favoring early infarct-related artery reocclusion. We investigated the effects of a newer thrombolytic regimen with half-dose double-bolus reteplase (2 x 5 IU, 20 patients) combined with abciximab versus full-dose reteplase (2 x 10 IU, 18 patients) on the fibrinolytic and the hemostatic system in patients with acute ST-segment elevation (in the electrocardiogram) myocardial infarction. The thrombolytic regimen with half-dose reteplase in combination with abciximab caused in vivo a lower systemic plasminemia and a lower paradoxical activation of the contact phase of the coagulation system (measured as activated factor XII); a lower paradoxical thrombin activation/generation; and a lesser extent of fibrinogen breakdown compared with the reteplase regimen. These results could be, at least in part, a possible explanation for the observed significantly lower rates of reinfarction until 7 days after enrollment and of recurrent ischemia in the combination group in the Global Use of Strategies to Open Occluded Coronary Arteries V (GUSTO V) trial.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticoagulantes/uso terapêutico , Fibrinolíticos/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico , Abciximab , Idoso , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Proteínas Recombinantes/administração & dosagem , Ativador de Plasminogênio Tecidual/administração & dosagemRESUMO
Pathophysiological aspects of acute myocardial infarction include altered hemostatic and fibrinolytic systems as well as platelet activation. Treatment with thrombolytics and GP IIb/IIIa antagonists has been described as having an additional influence on these systems. We investigated the effects of a new thrombolytic regimen with half-dose double-bolus reteplase (2 x 5 IU, 20 patients) combined with abciximab versus full dose reteplase (2 x 10 IU, 18 patients) on platelet-granulocyte complexes and on thrombin-antithrombin III complexes in patients with acute ST-segment elevation myocardial infarction. In vivo, the thrombolytic regimen with half-dose reteplase in combination with abciximab caused fewer platelet-granulocyte aggregates (measured as percentage of CD41-positive granulocytes) and a lower paradoxical activation of the coagulation system (measured as thrombin-antithrombin III complex) compared with the reteplase regimen. The combination regimen could therefore have benefical effects on platelet-induced leukocyte activation and leukocyte-mediated proinflammatory/cytotoxic effects as well as on granulocyte-induced effects on endothelium, tissue damage and coagulation. This could be, at least in part, a possible explanation for the significantly lower rates of reinfarction, recurrent ischaemia and percutaneous coronary interventions observed during the early phase after an acute myocardial infarction in the combination group in the GUSTO-V trial.