RESUMEN
Projects to manage arthropod pests using entomopathogenic nematodes (EPNs) in Brazil, Korea and USA are reviewed to identify conditions and practices that affected the use of EPNs for pest management. A proliferation of covered agriculture in Korea, the growth in demand for high value, pesticide-free produce in Korea and Brazil, and the cost-effectiveness of EPNs created favorable conditions for the widespread adoption of EPN products in Brazilian guava orchards and Korean vegetable greenhouses. In Florida, EPNs imported from South America function successfully as classical biocontrol agents against invasive mole crickets attacking pasture and turf. However, the low value of pasture and the availability of cost-effective chemical insecticides in turf have depressed the demand for EPN products to control mole crickets. In Florida citrus orchards, a recent, dramatic increase in the use of chemical insecticides to control an arthropod vector of a devastating bacterial disease of citrus (huanglongbing) reduced the demand for EPN products to control Diaprepes root weevils. Nevertheless, a rich and diverse EPN fauna in the Florida peninsula provides significant control of subterranean stages of root weevils in some habitats, and is the focus of research to develop cultural practices that exploit the potential for increased pest management through EPN conservation.
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BACKGROUND: Serotonin (5-hydroxytryptamine, 5-HT) levels are increased by light exposure but the role and mechanism of 5-HT in the pigmentation of skin cells are unclear. OBJECTIVES: To clarify the effect of 5-HT on melanogenesis and to determine the 5-HT receptor subtype involved. METHODS: B16F10, SK-MEL-2 and Melan-A cells were cultured in Dulbecco's modified Eagle's medium with low fetal bovine serum. The three cell lines were treated with various concentrations of 5-HT, and 5-HT receptor agonists and antagonists. The involvement of the 5-HT receptor 2A (5-HTR2A) was examined by gene silencing and use of 5-HTR2A antagonists. RESULTS: 5-HT and the 5-HTR2A agonist, DOI, increased melanogenesis in the three cell lines. These increased events were suppressed by 5-HTR2A antagonists or gene silencing of the HTR2A gene. CONCLUSIONS: 5-HTR2A is involved in melanogenesis. These findings highlight the role of 5-HT and suggest new ways of controlling melanogenesis.
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Melaninas/biosíntesis , Melanosis/etiología , Receptor de Serotonina 5-HT2A/fisiología , Serotonina/fisiología , Animales , Western Blotting , Movimiento Celular/efectos de los fármacos , Silenciador del Gen , Humanos , Melanocitos/metabolismo , Melanoma/fisiopatología , Melanosis/metabolismo , Ratones , ARN Interferente Pequeño/farmacología , Receptor de Serotonina 5-HT2A/genética , Serotonina/farmacología , Agonistas del Receptor de Serotonina 5-HT2/farmacología , Antagonistas del Receptor de Serotonina 5-HT2/farmacología , Neoplasias Cutáneas/fisiopatología , Células Tumorales CultivadasRESUMEN
This study determined the mechanical performance of bioactive restoratives in cariogenic environments and compared the flexural properties of various bioactive materials. The materials evaluated included a conventional resin-based composite (Filtek Z350 [FZ]) and 3 bioactive restoratives, namely an alkasite (Cention N [CN]), a giomer (Beautifil-bulk Restorative [BB]), and an enhanced resin-modified glass ionomer (Activa Bioactive Restorative [AV]). Beam-shaped specimens (12 x 2 x 2 mm) were produced, randomly allocated to 4 groups (n=10), and conditioned in deionized solution, remineralizing solution, demineralizing solution (DE), or pH cycled for 14 days at 37°C. After conditioning/pH cycling, the specimens were subjected to 3-point flexural testing. Flexural data were subjected to statistical analysis using analysis of variance or Tukey's test (α=0.05). Mean flexural modulus and strength ranged from 3.54 ± 0.33 to 7.44 ± 0.28 GPa, and 87.07 ± 8.99 to 123.54 ± 12.37 MPa, respectively. While the flexural modulus of the bioactive restoratives was not affected by cariogenic/acidic conditions, flexural strength usually decreased, with the exception of CN. The strength of BB was significantly reduced by DE and pH cycling, while that of AV was lowered by DE. For all conditioning mediums, AV had a significantly lower modulus than the other materials. Apart from conditioning in DE, where differences in flexural strength was insignificant, FZ and AV were generally significantly stronger than BB and CN. The effect of cariogenic environments on flexural strength was found to be material dependent, and aside from the alkasite material (CN), cariogenic conditions were observed to significantly decrease the strength of bioactive restoratives.
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Resinas Compuestas , Resistencia Flexional , Materiales Dentales , Ensayo de Materiales , DocilidadRESUMEN
The effects of several potentially nephrotoxic furans on urinary levels of N-acetylglucosaminidase (NAG) were examined to determine whether this test might serve as a useful quantitative index of nephrotoxicity for this series of compounds. Whereas others have found that nephrotoxins such as sodium salicylate and biphenyl cause increases in urinary NAG, we observed that these furans, which were shown to be nephrotoxic by histological procedures, caused significant decreases in urinary levels of the enzyme. This effect was dose-related in the one case examined.
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Acetilglucosaminidasa/orina , Furanos/toxicidad , Hexosaminidasas/orina , Enfermedades Renales/inducido químicamente , Animales , Compuestos Heterocíclicos/toxicidad , Masculino , Ratones , Ratones Endogámicos ICR , Salicilatos/toxicidad , Ácido SalicílicoRESUMEN
A series of 28 diarylsulfonylureas with antitumor activity was subjected to a three-dimensional quantitative activity relationship (3D-QSAR) study. Three different QSAR methods, comparative molecular field analysis (CoMFA), hologram QSAR (HQSAR) and comparative molecular similarity indices analysis (CoMSIA), were compared in terms of their potential for predictability. All three QSAR-based models had good predictability and yielded q(2) values 0.74, 0.63 and 0.72, respectively. The CoMFA model provided the highest q(2) and r(2) values, which implied the significance of correlation of steric and electrostatic fields with biological activities. The number of components was 3-4 for all three QSAR methods. The quality of HQSAR or CoMSIA was slightly lower than that of CoNFA in terms of q(2) and r(2) values. HQSAR does not require the generation of a three-dimensional structure of molecules and CoMSIA does not require molecular superposition, therefore they are faster than CoMFA in data processing.
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Alcanos/síntesis química , Alcanos/farmacología , Antineoplásicos/química , Urea/análogos & derivados , Urea/síntesis química , Urea/farmacología , Antineoplásicos/farmacología , Carcinoma/metabolismo , Humanos , Pulmón/citología , Modelos Moleculares , Relación Estructura-Actividad Cuantitativa , Células Tumorales CultivadasRESUMEN
The alpha,beta-unsaturated amide that is incorporated into the basic structural frame of a simple substrate molecule of angiotensin converting enzyme was found to serve as a Michael acceptor for the catalytic carboxylate of Glu-127, inhibiting the enzyme irreversibly.
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Inhibidores de la Enzima Convertidora de Angiotensina/síntesis química , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Prolina/análogos & derivados , Animales , Cromatografía Líquida de Alta Presión , Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Concentración 50 Inhibidora , Cinética , Peptidil-Dipeptidasa A/metabolismo , Prolina/síntesis química , Prolina/farmacología , ConejosRESUMEN
The amount of stanozolol and 3'-hydroxystanozolol in urine was determined after oral administration of stanozolol. A gas chromatograph/mass selective detector equipped with a capillary column was used for these determinations. The GC/MS was operated in the SIM mode, and m/z 581, 669, and 315 were monitored for stanozolol, 3'-hydroxystanozolol, and calusterone (internal standard), respectively. The detection limit was approximately 1 ng/mL for both steroids. The maximum excretion rate of stanozolol was reached in 8 h and the maximum of 3'-hydroxystanozolol in 19 h. However, only 3% of the administered amount was recovered in urine.
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Doping en los Deportes , Estanozolol/orina , Detección de Abuso de Sustancias/métodos , Administración Oral , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Estanozolol/administración & dosificación , Factores de TiempoRESUMEN
When phenothiazine drugs (chlorpromazine, promazine, promethazine, propiomazine, propionylpromazine, trifluoperazine and trimeprazine) were reacted with m-chloroperbenzoic acid, N-demethylated phenothiazines were obtained in moderate yield. The mass spectra of the N-demethylated phenothiazines showed either m/z 44 and 72 or m/z 58 as characteristic ions depending on their side chain. The N-demethylated propiomazine was identified as a metabolite of propiomazine from the urine of a rat which was given propiomazine orally.
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Antipsicóticos/orina , Animales , Antipsicóticos/metabolismo , Clorobenzoatos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Fenotiazinas/metabolismo , Fenotiazinas/orina , Ratas , Ratas EndogámicasRESUMEN
This study describes the use of gas chromatography/mass spectrometry with selected ion monitoring to screen 18 anabolic steroids banned by the International Olympic Committee. These anabolic steroids are analyzed in two fractions depending on their excretion pattern: nonconjugated (free) or conjugated fraction. The wet procedure of extracting steroids from urine consists of an initial isolation of lipophilic compounds on a column packed with Amberlite XAD-2 resin, followed by enzymatic hydrolysis with beta-glucuronidase from Escherichia coli. After extraction, the hydrolyzed steroids are derivatized to the corresponding trimethylsilyl ethers. The derivatized steroids are analyzed by gas chromatography/mass spectrometry with selected ion monitoring of their characteristic ions. It takes 12 and 26 min to run GC/MS and edit the raw data for nonconjugated and conjugated fractions respectively.
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Anabolizantes/orina , Doping en los Deportes , Detección de Abuso de Sustancias/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , HumanosRESUMEN
Three dimensional QSAR studies for antihistamine and antibradykinin effects of new piper azine derivatives were conducted using the comparative molecular field analysis. Electro static and steric factors, but not hydrophobic factor, of the synthesized compounds were correlated with the antagonistic effect.
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Bradiquinina/antagonistas & inhibidores , Antagonistas de los Receptores Histamínicos/farmacología , Piperazinas/farmacología , Animales , Humanos , Modelos Moleculares , Relación Estructura-Actividad Cuantitativa , Relación Estructura-ActividadRESUMEN
In order to study the simultaneous determination of (+)- and (-)-cetirizine in human urine we have developed a chiral separation method by HPLC. A chiral stationary phase of alpha1-acidglycoprotein, the AGP-CSP, was used to separate the enantiomers. The pH of the phosphate buffer, as well as the content of the organic modifier in the mobile phase, markedly affected the chromatographic separation of (+)- and (-)-cetirizine. A mobile phase of 10 mmol/l phosphate buffer (pH 7.0)-acetonitrile (95: 5, v/v) was used for the urine assays. Ultraviolet absorption was monitored at 230 nm and roxatidine was employed as the internal standard for quantification. (+)-Cetirizine, (-)-cetirizine and the internal standard were eluted at retention times of 12, 16, and 32 mins, respectively. The detection limit for cetirizine enantiomers was 400 ng/ml of urine. A pharmacokinetic study was conducted with the help of 5 healthy female volunteers who were administered with a single oral dose of racemic cetirizine (20 mg). The peak area ratios provided by the cetirizine enantiomers were linear (r>0.997) over a concentration range of 2.5-200 microg/ml. The peak of the excreted cetirizine enantiomers appeared in the urine sample during the period of 1-2 hrs following the administration of the oral dose. The excreted level of (+)-cetirizine was slightly higher than (-)-cetirizine but the difference was not statistically significant. However, this method appears to have applications for enantioselective pharmacokinetic studies of racemic drugs.
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Cetirizina/orina , Antagonistas de los Receptores Histamínicos H1/orina , Adulto , Cetirizina/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Femenino , Antagonistas de los Receptores Histamínicos H1/aislamiento & purificación , Humanos , Indicadores y Reactivos , Espectrofotometría Ultravioleta , EstereoisomerismoRESUMEN
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06-5.5 microM.
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Inhibidores de la Enzima Convertidora de Angiotensina/síntesis química , Compuestos Epoxi/síntesis química , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Sitios de Unión , Compuestos Epoxi/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Peptidil-Dipeptidasa A/química , Espectrofotometría InfrarrojaRESUMEN
Adults of the brown planthopper (BPH) and the whitebacked planthopper (WBPH) that migrated into Korea from China were not parasitized by the mermithid, Agamermis unka. BPH and WBPH collected from Korean rice fields were parasitized. Parasitism of BPH in the lst-3rd, 4th, and 5th instars, and adults was 31.5%, 61.5%, 66.4%, and 45.5%, respectively, whereas parasitism of the same stages of WBPH was 50%, 50%, 100% and 90.7%, respectively. Parasitism of BPH by A. unka significantly reduced the number of eggs. Only 4.2% of the parasitized females contained eggs, whereas 85.6% of unparasitized females had eggs. Tilling of rice fields significantly increased mermithid parasitism of BPH. Mermithids parasitized 39.3% of caged adults in the untilled field and 77.8% in the tilled field.
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Afenestrata koreana n. sp. collected from roots of bamboo (Phyllostachys pubescens) in Gyeongnam Province in the southern part of the Korean peninsula is described and illustrated. Its primary differentiating characteristics are a globose to subspherical body in adults with a prominent neck and terminal cone, thick cuticle, terminal vulva, and deep vagina. Fenestra, bullae, and underbridge are absent. The anus is on the immediate posterior side of the cone. Superficial small tubercules cover all the terminal cone area. The new species differs markedly from the other two known species in the genus, specifically in having three incisures in the lateral field of juveniles and a shorter stylet length in juveniles and adults. The male is unknown.
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The mermithid Agamermis unka, a parasite of the brown planthopper (BPH), was found in many rice paddies in Gyeongnam Province, Korea. Nematode parasitism of adult BPH varied from year to year, reaching as high as 50% in paddies not treated with an insecticide. Parasitism was lower in insecticide-treated paddies. Generally, mermithid parasitism was higher in BPH adults collected from the lower part (19%) compared with adults collected from the upper part (8%) of the rice plant and in brachypterous (57%) compared with macropterous forms (8%). No difference in parasitism between first (54%) and second (57%) generation was observed.
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Nematodes found in Ips paraconfusus from ponderosa pine in California were an undescribed species of Parasitaphelenchus, Contortylenchus elongatus, C. reversus, and C. brevicomi. C. elongatus, the most commonly found contortylenchid, was present in 98.2% of the contortylenchid-parasitized beetles. Only one nematode parasite of the gut, a Parasitorhabditis sp., was isolated. Although significant differences in parasitism were observed, they were by collection sites, rather than by elevation or bole sources (slash or standing). Significant changes in parasitism between fall and spring collections were observed but not at every site. Nematode parasitism in the F generation of I. paraconfusus by Parasitaphelenchus, Contortylenchus, or Parasitorhabditis increased or decreased from the parent generation depending upon the experiment.Nematode parasites from I. pini included an undescribed Parasitaphelenchus sp., two undescribed Contortylenchus spp., C. reversus and Parasitylenchus (= Neoparasitylenchus) ovarius from the hemocel, and Parasitorhabditis ipini from the gut. Parasitaphelenchus sp. was found in 99% and 45.3% of the beetles from Idaho and California, respectively. Of the 1,000 I. pini from Idaho and California, 157 were parasitized by the contortylenchid species or P. ovarius.
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The propionylpromazine concentrations in plasma after intramuscular administration to horses were determined using gas chromatography with nitrogen-phosphorus detection. After hydrolysis by beta-glucuronidase/arylsulphatase, the parent drug and three metabolites were detected in urine. The metabolites were identified as 2-(1-hydroxypropyl)promazine, 2-(1-propenyl)promazine and 7-hydroxypropionylpromazine by gas chromatography-mass spectrometry. No N-demethylated or sulphoxidated metabolites of propionylpromazine were observed in the horse urine.
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Promazina/análogos & derivados , Animales , Fenómenos Químicos , Química , Cromatografía de Gases , Cromatografía de Gases y Espectrometría de Masas , Caballos , Promazina/sangre , Promazina/metabolismo , Promazina/farmacocinéticaRESUMEN
Nematode yield is a decisive factor for successful large-scale commercial production of entomopathogenic nematode. Various carbon sources were tested in in-vitro liquid culture to improve the yield of the entomopathogenic nematode Heterorhabditis bacteriophora. Canola oil was the optimal carbon source for nematode culture compared to carbohydrates when applied as a sole carbon source. However, when some of carbohydrates were applied together with canola oil, significant increases in nematode yield were observed. When 25 mg glucose ml(-1) was supplemented to 25 mg oil-based liquid culture medium ml(-1), the highest nematode yield, 3.62 x 10(5) infective juveniles, was achieved at 12 days, but nematode growth was suppressed at higher than 75 mg glucose ml(-1). A fed-batch culture process was introduced in nematode liquid culture consisting of two growth phases: bacteria and nematode. In the oil fed-batch culture, in which only glucose was initially added and oil was fed to the culture after the bacterial growth phase concurrent with nematode inoculation, nematode yield increased up to 4.25 x 10(5) infective juveniles ml(-1), while the batch culture resulted in 3.60 x 10(5) infective juveniles ml(-1). These results indicate that glucose is a superior carbon source for the bacteria, whereas canola oil is optimal for the nematode. The application of fed-batch culture provides significant enhancement of nematode yield in in-vitro liquid culture.
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Glucosa/metabolismo , Nematodos/metabolismo , Animales , Medios de Cultivo , FermentaciónRESUMEN
Piperazine derivatives were prepared as histamine antagonists. Some of the synthesized compounds showed dual antagonistic activity against bradykinin as well as histamine.
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Antagonistas de los Receptores de Bradiquinina , Antagonistas de los Receptores Histamínicos H1/síntesis química , Antagonistas de los Receptores Histamínicos H1/farmacología , Piperazinas/síntesis química , Piperazinas/farmacología , Animales , Cobayas , Técnicas In Vitro , RatasRESUMEN
Steinernema longicaudum Shen & Wang is redescribed based on a comparative morphological study of specimens from the type isolate from China, and two other isolates recovered from Korea and the USA. For the first and second generation female, the location of the vulva, shape of the vulval lips, and shape and length of the tail were newly observed diagnostic characters. A more detailed description of the morphology of the male spicules and gubernaculum, and the arrangement of the genital papillae is included. A description, based on scanning electron microscopy observations, of the lateral field pattern of the third-stage infective juveniles is also provided. Additionally, restriction fragment length polymorphism profiles based on the internal transcribed spacer region, and cross-breeding tests supplement the description of this species.