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1. The aim of this study was to investigate if male-to-female aggression of common pheasants in the course of the breeding season was related to the concentration of plasma testosterone and/or other biochemical plasma indicators in male pheasants housed in breeding cages. The influence of season on the concentration of testosterone and biochemical indicators was also investigated. 2. Males were divided into non-aggressive and aggressive groups during the breeding season based on ethological evaluation. At the beginning, in the middle and at the end of the breeding season, a blood sample was taken from all males on the same day and the concentration of selected biochemical indicators and the total circulating testosterone in the plasma were determined. 3. Male-to-female aggression during the breeding season of pheasants was not influenced by the total plasma testosterone of males. 4. The concentration of total plasma testosterone in males decreased gradually during the breeding season. 5. Male-to-female aggression of pheasants did not have a significant effect on any of the assessed biochemical indicators. 6. The influence of the breeding season affected the activities of alanine aminotransferase and aspartate aminotransferase as well as the concentrations of glucose, magnesium, potassium and chloride in the blood plasma of cage-housed male pheasants.
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Agresión , Galliformes/fisiología , Testosterona/sangre , Crianza de Animales Domésticos , Animales , Femenino , Galliformes/sangre , MasculinoRESUMEN
AIM: An open-label, phase I dose-escalation trial was performed in adult patients with various solid cancers to identify the maximum tolerated dose (MTD), to assess the safety, pharmacokinetic profile and anti-tumour activity of the new prodrug CAP7.1. The prodrug is converted to its active moiety etoposide via carboxylesterases in selective cells leading to a better tolerability and higher efficacy in therapeutic resistance cells and children with refractory neuroblastoma. PATIENTS AND METHODS: Eligible adult patients with advanced, refractory, solid malignancies received CAP7.1 as intravenous infusion on 5 consecutive days. Doses were escalated in four cohorts consisting of three to six patients, with a starting dose of 45 mg/m2/day. Treatment cycles were repeated in 21-day intervals in the absence of disease progression and prohibitive toxicity. The safety, pharmacokinetics and efficacy were evaluated, and the MTD and dose-limiting toxicity (DLT) were determined. RESULTS: Nineteen patients were assigned to four CAP7.1 dose cohorts (45, 90, 150 and 200 mg/m2/day). CAP7.1 was well tolerated. Haematotoxicity was observed at the two highest dose levels including three DLTs (two febrile neutropenia and one sepsis) only and were reversible with adequate therapy. No organ toxicity was observed. Non-haematological toxicities (mild-moderate) consist mainly of nausea, fatigue, vomiting, pyrexia and alopecia. One partial response and 11 stable diseases were observed as supporting signs of efficacy. CONCLUSION: MTD of CAP7.1 was reached at the dose of 200 mg/m2. A favourable safety profile and initial anti-tumour efficacy of CAP7.1 in therapeutic refractory tumours warrant further evaluation in clinical studies.
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Etopósido/administración & dosificación , Neoplasias/tratamiento farmacológico , Profármacos/administración & dosificación , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Etopósido/efectos adversos , Etopósido/farmacocinética , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/metabolismo , Profármacos/efectos adversos , Profármacos/farmacocinéticaRESUMEN
Selexipag (Uptravi) is an oral selective IP prostacyclin receptor agonist approved for the treatment of pulmonary arterial hypertension (PAH). The pivotal GRIPHON study was the largest clinical study ever conducted in PAH patients, providing long-term data from 1,156 patients. PAH comedication did not affect exposure to selexipag, while exposure to its active metabolite ACT-333679 was reduced by 30% when taken in combination, clinically not relevant in the context of individual dose up-titration. Using log-linear regression models linking model-predicted steady-state exposure to pharmacodynamics (PD), exposure to selexipag and ACT-333679 showed some statistically significant, albeit not clinically relevant, effects on exercise capacity, laboratory values, and the occurrence of prostacyclin-related adverse events, but not on vital signs or adverse events denoting hemorrhage. Using suitable modeling techniques, the GRIPHON study yielded clinically relevant data with limited burden of pharmacokinetics (PK) blood sampling, demonstrating that PK/PD modeling enables firm conclusions even with sparse PK and PD sampling.
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Acetamidas/farmacocinética , Acetamidas/uso terapéutico , Antihipertensivos/farmacocinética , Antihipertensivos/uso terapéutico , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/metabolismo , Modelos Biológicos , Pirazinas/farmacocinética , Pirazinas/uso terapéutico , Acetamidas/efectos adversos , Acetamidas/sangre , Acetatos/sangre , Adulto , Antihipertensivos/efectos adversos , Antihipertensivos/sangre , Bilirrubina/sangre , Método Doble Ciego , Tolerancia al Ejercicio/efectos de los fármacos , Femenino , Humanos , Hipertensión Pulmonar/sangre , Recuento de Leucocitos , Masculino , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Pirazinas/efectos adversos , Pirazinas/sangre , Resultado del TratamientoRESUMEN
BACKGROUND: Interleukin (IL)-17A has major proinflammatory activity in psoriatic lesional skin. OBJECTIVES: To assess the efficacy and safety of secukinumab, a fully human IgG1κ monoclonal anti-IL-17A antibody, in moderate-to-severe plaque psoriasis in a phase II regimen-finding study. METHODS: A total of 404 patients were randomized to subcutaneous placebo (n = 67) or one of three secukinumab 150 mg induction regimens: single (week 0; n = 66), early (weeks 0, 1, 2, 4; n = 133) and monthly (weeks 0, 4, 8; n = 138 patients). The primary outcome was ≥ 75% improvement from baseline Psoriasis Area and Severity Index score (PASI 75) at week 12. PASI 75 responders from active treatment arms at week 12 were rerandomized to either a fixed-interval (secukinumab 150 mg at weeks 12 and 24; n = 65) or a treatment-at-start-of-relapse maintenance regimen (secukinumab 150 mg at visits at which a start of relapse was observed; n = 67). RESULTS: At week 12, early and monthly induction regimens resulted in higher PASI 75 response rates vs. placebo (54·5% and 42·0% vs. 1·5%; P < 0·001 for both). Among PASI 75 responders at week 12 entering the maintenance period, PASI 75 and PASI 90 achievement at least once from week 20 to week 28 was superior with the fixed-interval regimen [85% (n = 55) and 58% (n = 38), respectively] vs. the start-of-relapse regimen [67% (n = 45), P = 0·020, and 21% (n = 14), respectively]. Fifteen weeks after last study drug administration, < 10% of patients in the fixed-interval and start-of-relapse groups experienced a start of relapse. No immunogenicity was observed, and no injection-site reactions were reported. Reported cases of neutropenia were mild-to-moderate (≤ grade 2); none was associated with clinically significant adverse events or resulted in study discontinuation. Due to the brief duration of the safety assessment, no firm conclusions can be drawn regarding long-term safety. CONCLUSIONS: Secukinumab shows efficacy for induction and maintenance treatment of moderate-to-severe plaque psoriasis.
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Anticuerpos Monoclonales/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Psoriasis/tratamiento farmacológico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Peso Corporal , Fármacos Dermatológicos/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Quimioterapia de Inducción/métodos , Inyecciones Intradérmicas , Quimioterapia de Mantención/efectos adversos , Quimioterapia de Mantención/métodos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
We propose a framework for tracking arbitrary complex cell boundary movements, relying on a unique definition of protrusion and retraction as the pathlength a virtual edge marker traverses when moving continuously perpendicular to the cell boundary. We introduce the level set method as a numerical scheme to reconstruct continuous boundary movement in time-lapse image sequences with finite time sampling. For moderately complex movements, we describe a numerically less expensive method that satisfactorily approximates the definition. Densely sampled protrusion and retraction rates were accumulated in space-time charts revealing distinct morphodynamic states. Applying this technique to the profiling of epithelial cell protrusion we identified three different states. In the I-state, long cell edge sectors are synchronized in cycles of protrusion and retraction. In the V-state random bursts of protrusion initiate protrusion waves propagating transversally in both directions. Cells switch between both states dependent on the Rac1 activation level. Furthermore, the persistence of transversal waves in the V-state depends on Arp2/3 concentration. Inhibition of PAK shifts cells into a lambda-state where continuous protrusion is occasionally interrupted by self-propagating ruffles. Our data support a model where activation of Rac1 mediates the propagation of protrusion waves, whose persistence depends on the relative abundance of activated Arp2/3 and polymerizable G-actin.
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Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Membrana Celular/fisiología , Extensiones de la Superficie Celular/fisiología , Células Epiteliales/fisiología , Proteína de Unión al GTP rac1/metabolismo , Actinas/metabolismo , Animales , Línea Celular , Simulación por Computador , Humanos , Ratones , Modelos BiológicosRESUMEN
BACKGROUND: Symptomatic intradialytic hypotension (IDH) associated with increased mortality in hemodialysis patients is difficult to predict and hence prevent. Artificial Neural Networks (ANNs) are promising tools to solve multidimensional non-linear problems. The aim of the study was to verify in which way mathematical models, statistics or knowledge of patients influence the ability of the nephrologists to predict IDH. METHODS: The performance of ANNs was compared with that of independent nephrologists supported by a logistic regression giving odds ratio for each studied variable (NEPHiS) or of nephrologists in charge of the patients without (NEPHc) or with statistical support as for NEPHiS (NEPHcS). Data from 98 hemodialysis patients were analysed in order to select patients with frequent IDH (>10% of the dialysis sessions). Complete data on 1979 dialysis sessions from 7 patients were retrieved. The ability to predict the occurrence of hypotension episodes was compared (ROC curves) between ANNs, NEPHc/S (N=7) in Switzerland and NEPHiS from independent dialysis centers in Western Australia (N=10). RESULTS: ANN gave the most accurate correlation between estimated and observed IHD episodes compared to NEPHc (p<0.001), but a similar performance was attained by NEPHcS (p<0.001). NEPHiS were superior to NEPHc (P<0.05), but inferior to ANN (P<0.01). For a sensitivity of 80%, specificity was 44% for ANNs, 33% for NEPHcS and 20% for NEPHc. CONCLUSIONS: ANNs are superior to nephrologists in predicting IDH episodes; however when supported by a statistical analysis, nephrologists reach ANNs in their prediction ability. IDH still remains difficult to predict even with mathematical models.
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Hipotensión/diagnóstico , Hipotensión/epidemiología , Modelos Estadísticos , Redes Neurales de la Computación , Diálisis Renal , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hipotensión/etiología , Incidencia , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Diálisis Renal/efectos adversos , Diálisis Renal/estadística & datos numéricos , Estudios Retrospectivos , Suiza/epidemiologíaRESUMEN
Cell migration initiates by extension of the actin cytoskeleton at the leading edge. Computational analysis of fluorescent speckle microscopy movies of migrating epithelial cells revealed this process is mediated by two spatially colocalized but kinematically, kinetically, molecularly, and functionally distinct actin networks. A lamellipodium network assembled at the leading edge but completely disassembled within 1 to 3 micrometers. It was weakly coupled to the rest of the cytoskeleton and promoted the random protrusion and retraction of the leading edge. Productive cell advance was a function of the second colocalized network, the lamella, where actomyosin contraction was integrated with substrate adhesion.
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Citoesqueleto de Actina/fisiología , Actinas/fisiología , Movimiento Celular , Depsipéptidos , Células Epiteliales/fisiología , Seudópodos/fisiología , Citoesqueleto de Actina/efectos de los fármacos , Animales , Línea Celular , Células Cultivadas , Citocalasina D/farmacología , Células Epiteliales/ultraestructura , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Cinética , Macropodidae , Microscopía Fluorescente , Películas Cinematográficas , Péptidos Cíclicos/farmacología , Seudópodos/ultraestructura , SalamandridaeRESUMEN
A series of 6-chloro-3-phenyl-4-thioxo-2H-1,3-benzoxazine-2(3H)-ones 3 and a series of 6-chloro-3-phenyl-2H-1,3-benzoxazine-2, 4(3H)-dithiones 4 were synthesized by melting 6-chloro-3-phenyl-2H-1, 3-benzoxazine-2,4(3H)-dione and its derivatives substituted on the phenyl ring 2 with tetraphosphorus decasulfide. Compounds 2c-e, 3 and 4 exhibited in vitro activity against Mycobacterium tuberculosis, M. kansasii (two strains) and M. avium better than or comparable to that of isoniazid. Replacement of the oxo group by a thioxo group at position 4 led to improvement in activity against M. tuberculosis and M. kansasii. The Free-Wilson method and procedure developed by the authors were used to analyse the structure-activity and structure-antimycobacterial profile relationships, respectively.
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Antibacterianos/farmacología , Mycobacterium/efectos de los fármacos , Oxazinas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Oxazinas/síntesis química , Oxazinas/química , Especificidad de la EspecieRESUMEN
[reaction: see text] The reaction of silylalkynes and terminal alkenes proceeds with complete control of regioselectivity by the silyl substituent to give geometrically defined vinylsilanes. Since terminal alkynes normally give mixtures, protodesilylation of these adducts then constitutes a regioselective addition of terminal alkynes to terminal alkenes.
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Alquenos/química , Alquinos/química , Rutenio/química , Silanos/química , Catálisis , Silanos/síntesis química , Compuestos de Vinilo/síntesis químicaRESUMEN
The haplo-insufficient p53 knockout (p53+/-) and zetaglobin v-Ha-ras (Tg.AC) transgenic mouse models were compared to the conventional two rodent species carcinogen bioassay by prospectively testing nine chemicals. Seven of the chemicals classified as carcinogens in the conventional bioassay induced tumors in the liver or kidneys of B6C3F1 mice, and one (pentachlorophenol) also induced tumors in other tissues. Only three chemicals, furfuryl alcohol, pyridine, and pentachlorophenol, induced tumors in rats. The tumorigenic effect of pyridine was seen in F344 rats but not in Wistar strain rats. None of the chemicals induced tumors in the p53+/- transgenic mice, which is consistent with the absence of genotoxicity of these chemicals. Only two of the seven nongenotoxic carcinogens were positive in the Tg.AC model (lauric acid diethanolamine and pentachlorophenol). These results show that these transgenic models do not respond to many chemicals that show strain- or species-specific responses in conventional bioassays.
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Carcinógenos/toxicidad , Genes ras , Neoplasias Renales/inducido químicamente , Neoplasias Hepáticas Experimentales/inducido químicamente , Proteína p53 Supresora de Tumor/genética , Administración Oral , Administración Tópica , Animales , Pruebas de Carcinogenicidad , Modelos Animales de Enfermedad , Femenino , Neoplasias Renales/genética , Neoplasias Renales/patología , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Ratas , Ratas Endogámicas F344 , Ratas Wistar , Proteína p53 Supresora de Tumor/deficienciaRESUMEN
Transgenic rodent models have emerged as potentially useful tools in the assessment of drug and chemical safety. The transgenic Tg.AC mouse carries an inducible v-Ha-ras oncogene that imparts the characteristic of genetically initiated skin to these animals. The induction of epidermal papillomas in the area of topically applied chemical agents, for duration of not more than 26 weeks, acts as a reporter phenotype that defines the activity of the test article. We describe here the activity of six chemicals that have been previously characterized for activity in the standard 2-year bioassay conducted by the National Toxicology Program (NTP). Homozygous female Tg.AC mice were treated with benzene (BZ), benzethonium chloride (BZTC), o-benzyl-p-chlorophenol (BCP), 2-chloroethanol (2-CE), lauric acid diethanolamine (LADA) and triethanolamine (TEA). BZ and LADA induced skin papillomas in a dose-dependent manner, while BCP induced papillomas only at the highest dose. BZTC, 2-CE, and TEA exhibited no activity. The correspondence of chemical activity in Tg.AC mice with that in the 2-year bioassay was high. A comparison of responsiveness to BZ and LADA was made between hemizygous and homozygous female Tg.AC mice. Both genotypes appear to be equally sensitive to maximum doses of active compounds. The results reported here indicate that the Tg.AC transgenic mouse model can discriminate between carcinogens and noncarcinogens and that both mutagenic and nonmutagenic chemicals can be detected. These studies provide support for the adjunctive use of the Tg.AC transgenic mouse skin tumor model in drug and chemical safety assessment and for the prediction of the carcinogenic potential of chemicals.
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Pruebas de Carcinogenicidad/métodos , Carcinógenos/toxicidad , Ratones Transgénicos , Papiloma/inducido químicamente , Neoplasias Cutáneas/inducido químicamente , Animales , Relación Dosis-Respuesta a Droga , Femenino , Homocigoto , Ratones , Farmacogenética , Especificidad de la Especie , Tasa de SupervivenciaRESUMEN
Phenolphthalein, a common ingredient in nonprescription laxatives and a multisex, multispecies rodent carcinogen, was evaluated under chronic exposure conditions for genotoxicity in transgenic female mice heterozygous for the p53 gene (heterozygous TSG-p53 mice). Phenolphthalein was administered in the diet at 200, 375, 750, 3,000, and 12,000 ppm (corresponding to a time-weighted average of 37, 71, 146, 569, and 2,074 mg/kg/day, respectively) for 6 months (183 days). On days 39, 92, 137, and 183 of treatment, peripheral blood samples were collected and evaluated for the frequency of micronucleated polychromatic and normochromatic erythrocytes (MN-PCE and MN-NCE, respectively), the percentage of PCE (%PCE) among total erythrocytes, and the extent of DNA damage (single strand breaks, alkali labile sites, DNA crosslinking) in leukocytes. In addition, the extent of DNA damage was evaluated in liver parenchymal cells sampled from mice at the end of the 6-month treatment period. DNA damage was evaluated using the alkaline (pH > 13) Single Cell Gel (SCG) assay. In addition, using a modified SCG technique, the frequencies of leukocytes and liver parenchymal cells with extremely low molecular weight DNA (indicative of apoptosis and/or necrosis) were determined. At each sample time, phenolphthalein induced a highly significant, dose-dependent increase in the frequency of MN-PCE and MN-NCE and in %PCE. Maximal induction of MN-PCE and %PCE decreased with increasing treatment duration, most likely due to a treatment duration-dependent decrease in the relative amount of ingested phenolphthalein. A comparative analysis of the kinetochore status of MN in erythrocytes sampled from control mice and mice ingesting phenolphthalein at 12,000 ppm for 183 days indicates that the induced MN resulted predominantly but not exclusively from numerical chromosomal damage. The analysis for increased levels of DNA damage in blood leukocytes was inconclusive, with a small but statistically significant increase in DNA migration on days 39 and 137 but not on days 92 and 183. The extent of DNA migration in liver parenchymal cells sampled from mice at the end of treatment was not altered significantly. The frequencies of apoptotic and/or necrotic leukocytes and liver parenchymal cells were not increased among mice ingesting phenolphthalein. The lowest effective dose at which a significant genotoxic response (i.e., the induction of MN-NCE) was detected was 200 ppm, the lowest dose tested in this study. This dose in mice is comparable to doses (on a mg/m2 basis) experienced by humans.
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Catárticos/administración & dosificación , Daño del ADN/efectos de los fármacos , Eritrocitos Anormales/efectos de los fármacos , Genes p53/efectos de los fármacos , Genes p53/genética , Fenolftaleínas/administración & dosificación , Administración Oral , Animales , ADN/efectos de los fármacos , ADN/metabolismo , Dieta , Eritrocitos Anormales/química , Eritrocitos Anormales/ultraestructura , Femenino , Heterocigoto , Cinetocoros/efectos de los fármacos , Cinetocoros/metabolismo , Hígado/química , Hígado/citología , Hígado/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Micronúcleos con Defecto Cromosómico/química , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Pruebas de Micronúcleos , FenolftaleínaAsunto(s)
Amidas/síntesis química , Antibacterianos/síntesis química , Chlorella/fisiología , Mycobacterium/efectos de los fármacos , Plaguicidas/síntesis química , Piridinas/síntesis química , Amidas/farmacología , Antibacterianos/farmacología , Fenómenos Químicos , Química Física , Chlorella/efectos de los fármacos , Chlorella/metabolismo , Clorofila/biosíntesis , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Plaguicidas/toxicidad , Piridinas/farmacología , Espectrofotometría InfrarrojaRESUMEN
A series of 4-alkylthiopyridine-2-carbothioamides have been prepared and evaluated in vitro for antimicrobial activity. Chemical structures have been demonstrated by IR and 1H NMR data and by elemental analysis. The antimycobacterial activity of these compounds against Mycobacterium tuberculosis, Mycobacterium kansasii, Mycobacterium avium, and Mycobacterium fortuitum, and the antifungal activity against Candida albicans, Candida tropicalis, Candida krusei, Candida glabrata, Trichosporon beigelii, Trichophyton mentagrophytes, Aspergillus fumigatus, and Absidia corymbifera were determined by the MIC values. Compounds 3 exhibit good antimycobacterial activity compared to isoniazide. A moderate antifungal activity was observed against T. mentagrophytes. Activity is influenced by hydrophobicity of the alkyl group.
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Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Antifúngicos/síntesis química , Antifúngicos/farmacología , Piridinas/síntesis química , Piridinas/farmacología , Tioamidas/síntesis química , Tioamidas/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Piridinas/química , Tioamidas/químicaRESUMEN
Series of esters of 6-aminohexanoic acid, 7-aminoheptanoic acid, and 8-aminooctanoic acid were synthesized as candidates for novel skin penetration enhancers. The permeation of theophylline expressed in the form of the enhancement factor (EF) was studied with human cadaver skin by a diffusion cell technique in the presence of the esters 1-17 in the water vehicle. The permeation in the presence of the 6-aminohexanoates 1-5 was also studied in the olive oil vehicle. Of the compounds tested, the most satisfactory enhancement in the water vehicle and oil vehicle were observed with octyl 6-aminohexanoate (EF = 45.5) and decyl 6-aminohexanoate (EF = 19.5), respectively.
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Aminoácidos/farmacología , Absorción Cutánea/efectos de los fármacos , Aminoácidos/química , Cromatografía Líquida de Alta Presión , Difusión , Excipientes , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Relación Estructura-Actividad , Teofilina/farmacocinéticaRESUMEN
From 5-cyano-3-chloro-2-pyrazinecarboxamide) (II) hydrolysis in acid medium) yielded 3-chloro-2,5-pyrazinedicarboxamide (III), which in a reaction with sodium hydrogensulfide in dimethyl-formamide) yielded 3-mercapto-2,5-pyrazinedicarboxamide (IV). This compound through condensations with alkyl- and arylhalogenides in triethylamine) yielded 3-alkyl(or aryl) thio-2,5-pyrazinedicarboxamides of type I. The structure of compounds was confirmed by elemental analysis, IR and 1H NMR spectra. A microbiological evaluation was carried out; the antituberculous effect of these compounds is not higher than that of pyrazinamide.
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Pirazinas/química , Mycobacterium tuberculosis/efectos de los fármacos , Micobacterias no Tuberculosas/efectos de los fármacos , Pirazinas/farmacologíaRESUMEN
Forty-six 6-acylamido-2-alkylthiobenzothiazoles were tested in vitro for antimicrobial activity towards Mycobacterium avium. The values of logarithms of the minimal inhibitory concentrations (log MIC) are shown in Table 1. The relationships between chemical structure and the activity under study were studied by the Free-Wilson method. The results, contributions of the substituents in positions 2 and 6 and the contribution of the common benzothiazole part (marked C) to the activity (delta log MIC) are shown in Table 2. Regression equation correlating the contributions and fragmental hydrophobic constants (f) belonging to the unbranched alkyl groups bound to the sulphur atom in position 2 (see Table 2) are not statistically significant (equation 8). The initial data for a complex analysis of the structure--antimycobacterial activity relationships with regard to the equipotency of the activity towards the species mentioned below form the values of log MIC and the derived values delta log MIC towards Mycobacterium tuberculosis, M. kansasii (see ref.9) and M. avium (see above). According to it, to each drug, each molecular fragment, the vector of activities A is attributed (equation 1), or the vector of contributions a (equation 7). Complex analysis is based on the idea of comparison (similarity) of the drug under study with an "ideal" drug, which possesses the required profile of activities. The vector uk corresponding to it is given for the above-considered case (of wide spectrum) by relation 5, for the case of selectivity with regard to the 1st activity by relation 4. The fundamental concepts of vector algebra, particularly the scalar product of vectors (A, uk) (relation 3) are used as the criteria of decision.(ABSTRACT TRUNCATED AT 250 WORDS)
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Mycobacterium avium/efectos de los fármacos , Tiazoles/farmacología , Fenómenos Químicos , Química , Relación Estructura-ActividadRESUMEN
Adult female Swiss-Webster and B6C3F1 mice received distilled water only or water containing 0.1, 1.0, 10, 100, or 1000 ppb of aldicarb daily for 34 days. The target concentration of aldicarb present in the 10 ppb dosing solution was analytically verified on a daily basis as was its stability over a 48-hr period. To develop an immune profile of this compound, functional parameters measured after exposure included resistance to infectious viral challenge; quantitation of splenic antibody-forming cells to sheep erythrocytes and circulating serum antibody levels; splenic lymphocyte blastogenesis to T- and B-cell mitogens; and mixed-lymphocyte culture response. To supplement the functional assays, complete blood counts, differential leukocyte counts, and body and relative organ weights were measured. In addition, gross and histopathologic examinations of tissues relevant to the immune system were performed. The absence of significant effects on any of these parameters suggests that aldicarb at environmentally relevant exposure concentrations is not immunotoxic in rodents.