RESUMO
OBJECTIVE: Smoking and periodontitis are risk factors for developing rheumatoid arthritis (RA), suggesting a break of tolerance on mucosal surfaces. Immunoglobulin A (IgA) antibodies are part of the mucosal immune system. The dominant autoantibodies in RA are anti-cyclic citrullinated protein antibodies (ACPAs), and IgG and IgA subclasses exist simultaneously. This study aimed to investigate the association of ACPA IgA subtypes with disease activity and long-term radiographic outcomes in RA, compared with ACPA IgG. METHOD: Total ACPA IgG, IgA, IgA1, and IgA2 were quantified in serum from patients with early RA (n = 97). Patient characteristics, IgM rheumatoid factor (IgM-RF) status, clinical and biochemical disease activity scores, and radiographic status evaluated by total Sharp score (TSS), were assessed at baseline and after 2 and 11 years of treatment. RESULTS: All patients with ACPA IgA also had ACPA IgG. ACPA IgA positivity was associated with IgM-RF and male gender. Both ACPA IgA and IgG levels at baseline were weakly associated with disease activity markers. Baseline ACPA IgA and IgG did not show a linear correlation with radiographic status after 10 years, but could predict radiographic progression (ΔTSS ≥ 5 from 0 to 11 years), with positive likelihood ratios of 3.7 and 4.0, respectively. CONCLUSION: ACPA IgA and IgG were weakly associated with disease activity in early RA. RA patients with a ΔTSS ≥ 5 after 11 years of treatment had higher ACPA IgG and ACPA IgA levels at baseline; however, none of the ACPA subtypes was superior in predicting long-term radiographic progression.
Assuntos
Anticorpos Antiproteína Citrulinada , Artrite Reumatoide , Humanos , Masculino , Artrite Reumatoide/tratamento farmacológico , Fator Reumatoide , Autoanticorpos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Peptídeos CíclicosRESUMO
Analysis of volatile compounds was performed on 81 wheat varieties and landraces, grown under controlled greenhouse conditions, in order to investigate the possibility of differentiating wheat varieties according to their volatile compound profiles. Volatile compounds from wheat samples were extracted by dynamic headspace extraction and analysed by gas chromatography-mass spectrometry. Seventy-two volatile compounds were identified in the wheat samples. Multivariate analysis of the data showed a large diversity in volatile profiles between samples. Differences occurred between samples from Austria compared to British, French and Danish varieties. Landraces were distinguishable from modern varieties and they were characterised by higher averaged peak areas for esters, alcohols, and some furans. Modern varieties were characterised by higher averaged peak areas for terpenes, pyrazines and straight-chained aldehydes. Differences in volatile profiles are demonstrated between wheat samples for the first time, based on variety. These results are significant to plant breeders and commercial users of wheat.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Triticum/química , Compostos Orgânicos Voláteis/metabolismo , Álcoois/análise , Aldeídos/análise , VolatilizaçãoRESUMO
AIM: To screen five strains of lactic acid bacteria (LAB) isolated from rye sourdoughs for the potential production of antimicrobial substances. METHODS AND RESULTS: Lactobacillus sakei KTU05-06, Pediococcus acidilactici KTU05-7, Pediococcus pentosaceus KTU05-8, KTU05-9 and KTU05-10 isolated from rye sourdoughs were investigated for the production of bacteriocin-like inhibitory substances (BLIS). The supernatants of analysed LAB inhibited growth of up to 15 out of 25 indicator bacteria strains as well as up to 25 out of 56 LAB strains isolated from rye sourdoughs. Moreover, these five LAB were active against ropes-producing Bacillus subtilis and the main bread mould spoilage causing fungi -Aspergillus, Fusarium, Mucor and Penicillium. Lactobacillus sakei KTU05-6 demonstrated the best antibacterial properties and is resistant towards heat treatment even at 100°C for 60 min. CONCLUSIONS: The use of LAB-producing antibacterial substances may be a good choice as a co-starter culture to ensure the stability of sourdoughs and to avoid the bacterial and fungi spoilage of the end product. SIGNIFICANCE AND IMPACT OF THE STUDY: The antimicrobial compounds designated as sakacin KTU05-6, pediocin KTU05-8 KTU05-9, KTU05-10 and AcKTU05-67 were not identical to any other known BLIS, and this finding leads up to the assumption that they might be the novel.
Assuntos
Antibiose , Bacillus subtilis/crescimento & desenvolvimento , Bacteriocinas/biossíntese , Bacteriocinas/isolamento & purificação , Pão/microbiologia , Fungos/crescimento & desenvolvimento , Lactobacillaceae/metabolismo , Bacteriocinas/química , Lactobacillaceae/química , SecaleRESUMO
AIMS: To screen yeast strains isolated from grain-based food and beer for phytase activity to identify high phytase-active strains. METHODS AND RESULTS: The screening of phytase-positive strains was carried out at conditions optimal for leavening of bread dough (pH 5·5 and 30°C), in order to identify strains that could be used for the baking industry. Two growth-based tests were used for the initial testing of phytase-active strains. Tested strains belonged to six species: Saccharomyces cerevisiae, Saccharomyces pastorianus, Saccharomyces bayanus, Kazachstania exigua (former name Saccharomyces exiguus), Candida krusei (teleomorph Issachenkia orientalis) and Arxula adeninivorans. On the basis of initial testing results, 14 strains were selected for the further determination of extracellular and intracellular (cytoplasmic and/or cell-wall bound) phytase activities. The most prominent strains for extracellular phytase production were found to be S. pastorianus KVL008 (a lager beer strain), followed by S. cerevisiae KVL015 (an ale beer strain) and C. krusei P2 (isolated from sorghum beer). Intracellular phytase activities were relatively low in all tested strains. CONCLUSIONS: Herein, for the first time, beer-related strains of S. pastorianus and S. cerevisiae are reported as phytase-positive strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The high level of extracellular phytase activity by the strains mentioned previously suggests them to be strains for the production of wholemeal bread with high content of bioavailable minerals.
Assuntos
6-Fitase/metabolismo , Cerveja/microbiologia , Pão/microbiologia , Microbiologia de Alimentos , Leveduras/isolamento & purificação , Grão Comestível/microbiologia , Saccharomyces/enzimologia , Saccharomyces/crescimento & desenvolvimento , Saccharomyces/isolamento & purificação , Leveduras/enzimologia , Leveduras/crescimento & desenvolvimentoRESUMO
BACKGROUND: Peristomal skin problems are common and are treated by a variety of health professionals. Clear and consistent communication among these professionals is therefore particularly important. The Ostomy Skin Tool (OST) is a new assessment instrument for the extent and severity of peristomal skin conditions. Formal tests of reliability and validity are necessary for its use in clinical practice, research, and education. OBJECTIVES: To estimate inter- and intra nurse assessment variability of the OST and validity by comparison to a 'gold standard' (GS) defined by an expert panel. METHODS: Thirty photographs of peristomal skin were presented twice to 20 ostomy care nurses--10 from Denmark (DK) and 10 from Spain (ES)--to determine intra- and inter nurse assessment variability. The same photographs were presented to an international group of experts (dermatologist and ostomy care nurses), to establish a GS for comparison and validation of the results. RESULTS: A high intra-nurse assessment agreement, κ=0·84, was found with no differences in the intra-nurse assessments from the two groups of nurses (DK and ES). The inter-nurse assessment agreement was 'moderate to good', κ=0·54, with the agreement between the experts higher, κ=0·70. A high correlation between the scores from the nurses and the GS were seen in the lower part of the two scales [Discoloration, Erosion, Tissue overgrowth (DET) score<7)]. CONCLUSION: The study supported the validity of the OST. It is suggested that a categorical scale can be used to illustrate the severity of the DET scores.
Assuntos
Diagnóstico de Enfermagem , Estomia/efeitos adversos , Dermatopatias/patologia , Pele/patologia , Humanos , Variações Dependentes do Observador , Estomia/enfermagem , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
An experimental model using 3-day-old snatch-farrowed colostrum-deprived piglets co-infected with porcine circovirus type 2 (PCV2) and porcine parvovirus (PPV) is at present one of the best methods to study factors affecting development of postweaning multisystemic wasting syndrome (PMWS). A Swedish isolate of PCV2 (S-PCV2) retrieved in 1993 from a healthy pig has been used in this model to reproduce PMWS in pigs from Northern Ireland. This virus has been present in the Swedish pig population for at least a decade without causing any known PMWS disease problems, despite its potential pathogenicity. The reasons for this are unknown, but could be related to genetics, absence of triggers for PCV2 upregulation (infectious agent and/or management forms) within Swedish pig husbandry. In order to confirm the pathogenicity of S-PCV2, Swedish and Danish pigs were experimentally infected with this isolate according to the established model. Swedish pigs were also infected with a reference isolate of PCV2 (PCV2-1010) to compare the severity of disease caused by the two isolates in Swedish pigs. Both Danish and Swedish pigs developed PMWS after the experimental infection with S-PCV2. Antibodies to PCV2 developed later and reached lower levels in serum from pigs infected with S-PCV2 than in pigs inoculated with PCV2-1010. In general, pigs infected with S-PCV2 showed more severe clinical signs of disease than pigs infected with PCV2-1010, but pigs from all PCV2-inoculated groups displayed gross and histological lesions consistent with PMWS. All pigs inoculated with PPV, alone or in combination with PCV2, displayed interleukin-10 responses in serum while only pigs infected with PPV in combination with PCV2 showed interferon-alpha in serum on repeated occasions. Thus, the pathogenicity of S-PCV2 was confirmed and a role for cytokines in the etiology of PMWS was indicated.
Assuntos
Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Doenças dos Suínos/virologia , Síndrome de Emaciação/veterinária , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/análise , Temperatura Corporal , Peso Corporal , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/virologia , Circovirus/genética , Circovirus/imunologia , Circovirus/patogenicidade , DNA Viral/química , DNA Viral/genética , Dinamarca , Histocitoquímica/veterinária , Interferon-alfa/sangue , Interleucina-10/sangue , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Parvovirus Suíno/imunologia , Reação em Cadeia da Polimerase/veterinária , Suécia , Suínos , Doenças dos Suínos/imunologia , Virulência , Síndrome de Emaciação/imunologia , Síndrome de Emaciação/virologiaRESUMO
OBJECTIVE: Some epidemiological studies found a lower risk of cardiovascular disease among wine drinkers than among drinkers of other types of ethanol. This difference might be due to an effect of nonalcohol compounds in wine on important cardiovascular risk factors. The objective of this study was to compare the effect of red wine, nonalcohol compounds of red wine and placebo on established cardiovascular risk factors. DESIGN: A parallel, four-armed intervention study. SUBJECTS: A total of 69 healthy 38-74-y-old men and women. INTERVENTIONS: Subjects were randomised to either 1: red wine (males: 300 ml/day, 38.3 g alcohol/day, female subjects: 200 ml/day, 25.5 g alcohol/day), 2: water + red grape extract tablets (wine-equivalent dose), 3: water + red grape extract tablets (half dose), or 4: water + placebo tablets for a period of 4 weeks. No other sources of alcohol or anthocyanin were allowed. Plasma high-density lipoprotein (HDL)-cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol (LDL-C), HDL-C/LDL-C-ratio, very-low-density lipoprotein (VLDL)-triacylglycerol, total cholesterol, fibrinogen, factor VII coagulant activity (FVIIc), blood pressure, and body weight were determined before and after intervention. RESULTS: Wine consumption was associated with a significant 11-16% increase in fasting HDL-C and 8-15% decrease in fasting fibrinogen relative to not drinking wine. There were no significant treatment effects on fasting LDL-C, HDL-C/LDL-C-ratio, VLDL-triacylglycerol, total cholesterol, FVIIc, or blood pressure. Drinking wine was associated with relative body weight increments closely corresponding to the energy contributed by the alcohol component. CONCLUSION: Moderate red wine consumption for 4 weeks is associated with desirable changes in HDL-C and fibrinogen compared with drinking water with or without red grape extract. The impact of wine on the measured cardiovascular risk factors thus seems primarily explained by an alcohol effect. Our finding suggests that the putative difference in cardiac risk associated with wine vs other alcoholic beverages might be rather explained by other life-style confounders than by red wine contents of nonalcohol components.
Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , HDL-Colesterol/sangue , Etanol/administração & dosagem , Hemostasia/fisiologia , Vinho , Adulto , Idoso , Colesterol/sangue , LDL-Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Fibrinogênio/análise , Fibrinogênio/metabolismo , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Aumento de Peso , Vinho/análiseRESUMO
OBJECTIVE: To investigate the effect of a probiotic milk product containing the culture CAUSIDO(R) and of two alternative products on risk factors for cardiovascular disease in overweight and obese subjects. DESIGN: An 8 week randomized, double-blind, placebo- and compliance-controlled, parallel study. SUBJECTS: Seventy healthy, weight-stable, overweight and obese (25.0Assuntos
Doenças Cardiovasculares/prevenção & controle
, LDL-Colesterol/sangue
, Lactobacillus acidophilus
, Obesidade/dietoterapia
, Probióticos/uso terapêutico
, Adulto
, Análise de Variância
, Pressão Sanguínea
, Peso Corporal
, Doenças Cardiovasculares/etiologia
, Método Duplo-Cego
, Feminino
, Fibrinogênio/análise
, Humanos
, Absorção Intestinal
, Masculino
, Pessoa de Meia-Idade
, Cooperação do Paciente
, Probióticos/administração & dosagem
, Probióticos/efeitos adversos
, Fatores de Risco
, Iogurte
RESUMO
A direct and sensitive biochemical assay to measure the interaction in solution between peptides and affinity-purified major histocompatibility complex (MHC) class I molecules has been generated. Specific binding reflecting the known class I restriction of cytotoxic T cell responses was obtained. Adding an excess of beta 2-microglobulin (beta 2m) significantly increased the rate of peptide association, but it did not affect the rate of dissociation. Binding was complicated by a rapid and apparently irreversible loss of functional MHC class I at 37 degrees C which might limit the life span of empty MHC class I thereby preventing the inadvertent exchange of peptides at the target cell surface. All class I molecules tested bound peptides of the canonical octa- to nona-meric length. However, one class I molecule, Kk, also bound peptides, which were much longer suggesting that the preference of class I molecules for short epitopes is not absolute and may be caused by factors other than the peptide-MHC class I binding event itself.
Assuntos
Antígenos Virais/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Antígenos Virais/metabolismo , Ligação Competitiva , Linhagem Celular , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Peptídeos/imunologia , Ligação Proteica , Temperatura , Fatores de Tempo , Microglobulina beta-2/metabolismoRESUMO
The function of MHC class-I molecules is to sample peptides from the intracellular environment and present them to CD8+ cytotoxic T lymphocytes. To understand the molecular details of the assembly (and disassembly) of peptide-beta 2m-class-I complexes a biochemical peptide-class-I binding assay has been generated recently and this paper reports on a similar assay for the interaction between beta 2m and class I. As a model system human beta 2m binding to mouse class I was used. The assay is strictly biochemical using purified reagents which interact in solution and complex formation is determined by size separation. It is specific and highly sensitive. The observed affinity of the interaction, KD, is close to 0.4 nM. The rate of association at 37 degrees C is very fast (the ka is around 5 x 10(4)/M/s) whereas the dissociation is slow (the kd is around 8 x 10(-6)/s); the ratio of dissociation to association yields a calculated KD close to the observed value. At 37 degrees C almost all of the purified class I participates in binding of the exogenously offered beta 2m showing that a considerable exchange of the endogenous beta 2m occurs. Finally, it was demonstrated that exogenous beta 2m enhances binding to MHC class-I of short perfectly-matching peptides as well as longer peptides.
Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Proteínas de Ligação a RNA , Microglobulina beta-2/metabolismo , Sequência de Aminoácidos , Animais , Linfócitos B/imunologia , Linhagem Celular , Transformação Celular Viral/imunologia , Cromatografia em Gel , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Hemaglutininas Virais/metabolismo , Antígenos de Histocompatibilidade Classe I/isolamento & purificação , Humanos , Técnicas Imunológicas , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Proteínas do Nucleocapsídeo , Nucleoproteínas/síntese química , Nucleoproteínas/metabolismo , Peptídeos/síntese química , Peptídeos/metabolismo , Temperatura , Células Tumorais Cultivadas , Proteínas do Core Viral/síntese química , Proteínas do Core Viral/metabolismoRESUMO
To analyze the expression of mouse aminopeptidase N (APN) on the cells of the immune system a panel of rat monoclonal antibodies against mouse intestinal APN was generated. These antibodies were used to affinity purify functional mouse APN from both intestine and kidney, and by flow cytometry to examine the APN expression of the cells of the mouse immune system. An APN closely related, perhaps identical, to the intestinal APN was expressed on a subpopulation of spleen cells and stimulated peritoneal exudate cells, primarily representing antigen-presenting cells, such as B cells, macrophages, dendritic cells, and veiled cells. In contrast this APN expression could not be detected on thymocytes or spleen T cells. As a corollary, APN was expressed on monocyte, macrophage, and B lymphoma cell lines, but not on T hybridoma or thymoma cell lines. The expression of APN showed a striking correlation with the MHC class II expression in all the cell populations studied. This apparent co-expression suggests a role for APN in antigen processing.
Assuntos
Aminopeptidases/análise , Células Apresentadoras de Antígenos/enzimologia , Antígenos de Histocompatibilidade Classe II/análise , Aminopeptidases/imunologia , Animais , Anticorpos Monoclonais/imunologia , Biomarcadores , Antígenos CD13 , Linhagem Celular , Cromatografia de Afinidade , Sistema Imunitário/enzimologia , Camundongos , Camundongos Endogâmicos , Ratos , Células Tumorais CultivadasRESUMO
There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.
Assuntos
Endopeptidases/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Peptídeos/metabolismo , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Sistema Livre de Células , Epitopos , Técnicas In Vitro , Camundongos , Dados de Sequência Molecular , Muramidase/química , Muramidase/imunologia , Muramidase/metabolismo , Ligação ProteicaRESUMO
The pH dependence of the interaction between immunogenic peptide and MHC class II was studied both in a direct biochemical binding assay and in a functional Ag presentation assay. The two approaches yielded similar results. All of the peptides tested bound optimally to their relevant MHC class II restriction element at around pH 4.5. Indeed, several of the peptides did not bind at neutral pH. These results demonstrate that Ag under physiologic conditions meet MHC class II in a quite acidic environment. The very acidic pH optimal for peptide-MHC class II interaction is only found intracellularly and most notably in the endosome-lysosome compartment in which Ag processing is thought to occur. Thus, Ag processing and interaction with MHC class II molecules can potentially happen in the very same compartment. This yet undefined acidic compartment would have to contain proteolytic enzymes and MHC class II molecules.
Assuntos
Antígenos de Histocompatibilidade Classe II/metabolismo , Fragmentos de Peptídeos/metabolismo , Sequência de Aminoácidos , Humanos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Linfócitos T/imunologiaRESUMO
Three oximes currently being evaluated for adoption as replacement nerve agent therapy by various countries were compared for therapeutic efficacy against the toxic organophosphate inhibitors soman and tabun under a standard set of conditions. These oximes together with PAM-Cl and toxogonin, were also compared for efficacy against GF, an agent weaponized by Iraq. The order of effectiveness against soman was HI-6 greater than HLö-7 greater than pyrimidoxime. HLö-7 was very effective against tabun poisoning while HI-6 and pyrimidoxime were of moderate value. Against GF, HI-6 and HLö-7 were extremely effective, toxogonin was moderately effective, and PAM-Cl and pyrimidoxime were the least effective. HI-6 provided a high level of protection against all of the agents tested as did HLö-7 to a slightly lesser degree. The other oximes suffered from their lack of effects against one or more of the organophosphates.
Assuntos
Substâncias para a Guerra Química/toxicidade , Inibidores da Colinesterase/toxicidade , Organofosfatos/toxicidade , Compostos Organofosforados/toxicidade , Oximas/uso terapêutico , Soman/toxicidade , Animais , Cobaias , Dose Letal Mediana , Masculino , Intoxicação/tratamento farmacológicoRESUMO
The toxicity and efficacy of two oximes, HLö-7 and pyrimidoxime, were evaluated in mice and compared to those obtained with HI-6. HLö-7 and pyrimidoxime produced 24 h LD50 values of 356 and 291 mg/kg (i.p.), respectively. In combination with atropine (17.4 mg/kg, i.p.), HLö-7 was a very efficient therapy against poisoning by 3 x LD50 dose of soman, sarin and GF and 2 x LD50 dose of tabun with ED50 values of 12.4, 0.31, 0.32 and 25.2 mg/kg, respectively. In contrast, pyrimidoxime was a relatively poor therapy which resulted in ED50 values of greater than 150, 5.88, 100 and 71 mg/kg against poisoning by soman, sarin, GF and tabun, respectively. HLö-7 produced significant (p less than 0.05) reactivation of phosphorylated acetylcholinesterase, in vivo, resulting in 47, 38, 27 and 10% reactivation of sarin, GF, soman and tabun inhibited mouse diaphragm acetylcholinesterase, respectively. HLö-7 also antagonized sarin-induced hypothermia in mice suggesting that it reactivated central acetylcholinesterase. The potential of HLö-7 as a replacement oxime for the treatment of nerve agent poisoning is discussed.
Assuntos
Antídotos/farmacologia , Inibidores da Colinesterase/intoxicação , Reativadores da Colinesterase/farmacologia , Imidazóis/farmacologia , Bloqueadores Neuromusculares/intoxicação , Piridinas/farmacologia , Compostos de Piridínio/farmacologia , Animais , Imidazóis/toxicidade , Dose Letal Mediana , Masculino , Camundongos , Intoxicação por Organofosfatos , Organofosfatos , Oximas , Piridinas/toxicidade , Compostos de Piridínio/toxicidade , Sarina/intoxicação , Soman/intoxicaçãoRESUMO
Oximes, such as pralidoxime and toxogonin, are important therapeutic agents for the treatment of organophosphate (OP) nerve agent poisoning. Oximes can react with these nerve agents to give intermediates, phosphonylated oximes, which may be equally toxic to the parent OP. The sc LD50s of a series of phosphonylated 2-butanone and 2,3-butanedione monoximes were compared to the sc LD50s of their parent OPs (tabun, sarin, and VX) in CD-1 mice. In every case the derivatives were significantly less toxic than their parent nerve agents. Times to death, and to signs of poisoning, were inversely proportional to the dose of test compound, and in all mortalities, blood serum acetylcholinesterase (AChE) was severely inhibited. The relative potencies of these compounds, as well as soman, cyclohexyl methylphosphonofluoridate, and diisopropyl fluorophosphate, as inhibitors of AChE in primary cultures of mouse embryo neurons, correlated with their in vivo toxicities. The results indicate that mouse embryo neuron cultures may be a useful model with which to study this class of compounds.