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1.
Int J Toxicol ; 43(4): 368-376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38501993

RESUMO

In a 3-month toxicity study in cynomolgus monkeys at a European contract laboratory, animals were infected with HAV, initially resulting in hepatic injury being incorrectly attributed to the test compound. Elevated serum ALT/AST/GLDH (5- to 10-fold) were noted in individual animals from all groups including controls, with no apparent dose, exposure, or time-related relationship. Liver histopathology revealed minimal to slight inflammatory cell accumulation in periportal zones of most animals, and minimal to slight hepatocyte degeneration/necrosis in 10/42 animals from all groups. As these findings were more pronounced in 6 drug-treated animals, including 2/6 in the low dose group, the draft report concluded: "treatment-related hepatotoxicity at all dose levels precluded determination of a NOAEL." However, the unusual pattern of hepatotoxicity suggested a factor other than drug exposure might have caused the hepatic effects. Therefore, snap-frozen liver samples were tested for hepatitis viruses using a PCR method. Tests for hepatitis B, C, and E virus were negative; however, 20/42 samples were positive for hepatitis A virus (HAV). Infection was strongly associated with increased serum ALT/GLDH, and/or hepatocyte degeneration/necrosis. Re-evaluation of the study in light of these data concluded that the hepatic injury was not drug-related. A subsequent 6-month toxicology study in HAV-vaccinated cynomolgus monkeys confirmed the absence of hepatotoxicity. Identification of HAV infection supported progression of the drug candidate into later clinical trials. Although rarely investigated, subclinical HAV infection has occasionally been reported in laboratory primates, including those used for toxicology studies and it may be more prevalent than the literature indicates.


Assuntos
Hepatite A , Fígado , Macaca fascicularis , Animais , Masculino , Fígado/efeitos dos fármacos , Fígado/patologia , Feminino , Vírus da Hepatite A/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas , Alanina Transaminase/sangue , Testes de Toxicidade
2.
Acta Crystallogr C Struct Chem ; 75(Pt 12): 1635-1643, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802753

RESUMO

The structures of the cocrystalline adducts of 3-nitrophenol (3-NP) with 1,3,5,7-tetraazatricyclo[3.3.1.13,7]decane [HMTA, (1)] as the 2:1:1 hydrate, 2C6H5NO3·C6H12N4·H2O, (1a), with 1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecane [TATU (2)] as the 2:1 cocrystal, 2C6H5NO3·C7H14N4, (2a), and with 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane [TATD, (3)] as the 2:1 cocrystal, 2C6H5NO3·C8H16N4, (3a), are reported. In the binary crystals (2a) and (3a), the 3-nitrophenol molecules are linked via O-H...N hydrogen bonds into aminal cage azaadamantanes. In (1a), the structure is stabilized by O-H...N and O-H...O hydrogen bonds, and generates ternary cocrystals. There are C-H...O hydrogen bonds present in all three cocrystals, and in (1a), there are also C-H...O and C-H...π interactions present. The presence of an ethylene bridge in the structures of (2) and (3) defines the formation of a hydrogen-bonded motif in the supramolecular architectures of (2a) and (3a). The differences in the C-N bond lengths of the aminal cage structures, as a result of hyperconjugative interactions and electron delocalization, were analysed. These three cocrystals were obtained by the solvent-free assisted grinding method. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation from a mixture of hexanes.

3.
J Breath Res ; 12(3): 036016, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29593130

RESUMO

Rodent and nonhuman primate studies indicate that developmental programming by reduced perinatal nutrition negatively impacts life course cardio-metabolic health. We have developed a baboon model in which we feed control mothers (CON) ad libitum while nutrient restricted mothers are fed 70% of ad libitum global feed in pregnancy and lactation. Offspring of nutrient restricted mothers are intrauterine growth restricted (IUGR) at term. By 3.5 years IUGR baboons showed signs of insulin resistance, indicating a pre-diabetic phenotype, in contrast to healthy CON offspring. We hypothesized that a novel breath analysis approach would provide markers of the altered cardio-metabolic state in a non-invasive manner. Here we assess whether exhaled breath volatile organic compounds (VOCs) collected from this unique cohort of juvenile baboons with documented cardio-metabolic dysfunction resulting from in utero programming can be detected from their breath signatures. Breath was collected from male and female CON and IUGR baboons at 4.8 ± 0.2 years (human equivalent ∼13 years). Breath VOCs were quantified using a two-dimensional gas chromatography mass spectrometer. Two-way ANOVA, on 76 biologically relevant VOCs identified 27 VOCs (p < 0.05) with altered abundances between groups (sex, birthweight, and sex x birthweight). The 27 VOCs included 2-pentanone, 2-octanone, 2,2,7,7-tetramethyloctane and 3-methyl-1-heptene, which have not previously been associated with cardio-metabolic disease. Unsupervised principal component analysis of these VOCs could discriminate the four clusters defining males, females, CON and IUGR. This study, which is the first to assess quantifiable breath signatures associated with cardio-metabolic programing for any model of IUGR, demonstrates the translational value of this unique model to identify metabolites of programmed cardio-metabolic dysfunction in breath signatures. Future studies are required to validate the translatability of these findings to humans.


Assuntos
Testes Respiratórios/métodos , Sistema Cardiovascular/metabolismo , Compostos Orgânicos Voláteis/análise , Animais , Biomarcadores/metabolismo , Peso ao Nascer , Expiração , Feminino , Retardo do Crescimento Fetal/diagnóstico , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Papio , Gravidez , Análise de Componente Principal
4.
J Am Assoc Lab Anim Sci ; 56(1): 57-62, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28905716

RESUMO

The protozoan parasite Trypanosoma cruzi causes Chagas disease, uses kissing bugs as a vector, and is maintained in nature by a variety of wildlife reservoirs. Many natural cases of Chagas disease have been reported in NHP at facilities across the southern United States, where infected vectors and wildlife occur. Infection of NHP with T. cruzi can diminish their value as research models and lead to health problems and death. Identifying the modes of transmission and role of wildlife reservoirs in these facilities is therefore critical to guide interventions to reduce transmission. Here we investigated the role of roof rats (Rattus rattus), the most abundant nuisance species at a primate facility in San Antonio, in the maintenance and transmission of T. cruzi. The hearts and blood from the carcasses of the 145 rats collected underwent 2 independent PCR assays for detection of T. cruzi and other trypanosomes. The 145 hearts and 61 blood samples were all negative for T. cruzi. This population sample of 145 subjects would allow the detection of disease prevalence of 0.020 with a confidence level of 95%. The limited active vector surveillance efforts by our team combined with passive surveillance by facility personnel yielded no kissing bugs during the study period. Our results suggest that roof rats are unlikely to be important local reservoirs of T. cruzi at this facility. Further investigation of transmission dynamics across multiple years and more comprehensive vector surveillance is warranted.


Assuntos
Doença de Chagas/veterinária , Primatas/parasitologia , Doenças dos Roedores/parasitologia , Trypanosoma cruzi , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Habitação , Reação em Cadeia da Polimerase , Prevalência , Ratos , Doenças dos Roedores/epidemiologia , Texas/epidemiologia , Trypanosoma cruzi/genética
5.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 11): 1651-1653, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27840729

RESUMO

Solvent-free treatment of 1,3,6,8-tetra-aza-tri-cyclo-[4.3.1.13,8]undecano (TATU) with 4-chloro-3,5-di-methyl-phenol led to the formation of the title co-crystal, C7H14N4·2C8H9ClO. The asymmetric unit contains one aminal cage mol-ecule and two phenol mol-ecules linked via two O-H⋯N hydrogen bonds. In the aminal cage, the N-CH2-CH2-N unit is slightly distorted from a syn periplanar geometry. Aromatic π-π stacking between the benzene rings from two different neighbouring phenol mol-ecules [centroid-centroid distance = 4.0570 (11) Å] consolidates the crystal packing.

6.
Molecules ; 21(10)2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27727186

RESUMO

An efficient methodology to obtain novel antifungal analogs of brassinin 1 is described. Starting from l-tryptophan 2, N,N'-dialkylthiourea 4, 4-[(1H-indol-3-yl)methylene]-2-sulfanylidene-1,3-thiazolidin-5-one 5 and alkyl (2S)-3-(1H-indol-3-yl)-2-{[(alkylsulfanyl)carbonothioyl]amino}propanoate 6 type compounds were obtained as main products in different ratios depending on the reaction conditions via a tandem dithiocarbamate formation and Michael addition reaction. In order to understand the dependence of the reaction conditions on the mechanism pathway, a DFT/B3LYP study was performed. The results suggested the existence of competitive mechanistic routes which involve the presence of an ionic dithiocarbamate intermediate 9. Antifungal activities of all products were then evaluated against Fusarium oxysporum through mycelial growth inhibition using a microscale amended-medium assay. IC50 values were thus determined for each compound. These results showed that 6-related compounds can be considered as promissory antifungal agents.


Assuntos
Fusarium/efeitos dos fármacos , Indóis/síntese química , Indóis/farmacologia , Triptofano/química , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Indóis/química , Modelos Moleculares , Estrutura Molecular , Micélio/efeitos dos fármacos , Tiocarbamatos/química
7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o3041-2, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125806

RESUMO

The title chiral quaternary ammonium salt, C(13)H(25)N(4) (+)·I(-), was synthesized through the Menschutkin reaction between the cage aminal (2S,7S)-1,8,10,12-tetra-aza-tetra-cyclo-[8.3.1.1(8,12).0(2,7)]penta-decane and ethyl iodide. The quaternization occurred regioselectively on the nitrogen with major sp3 character. The crystal structure consists of anions and cations separated by normal distances. Ions are not linked through C-H⋯I hydrogen bonds.

8.
Artigo em Inglês | MEDLINE | ID: mdl-22259454

RESUMO

In the title compound, C(13)H(27)N(4) (+)·I(-), the ethyl-ene bridge is distorted from the ideal D(2d) symmetry wherein an N-C-C-N planar bridge, around whose C-C bond the C-N and C-H bonds are exactly eclipsed, is disordered over two sites with equal occupancies. In both disorder components, the hexyl chain adopts an ideal all-trans conformation. In the crystal, adjacent ions are connected by C-H⋯I hydrogen bonds, forming ionic pairs that are further linked into chains along [101] via a second C-H⋯I inter-action.

9.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2629, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22064969

RESUMO

The title compound C(14)H(29)N(4) (+)·I(-) salt, was obtained by the reaction of cage adamanzane-type aminal 1,3,6,8-tetra-aza-tricyclo-[4.3.1.1(3,8)]undecane with heptyl iodide. In the cation, the bond lengths and angles are within normal ranges, except for one N-C(ring) bond distance of 1.542 (3) Å, which is unexpectedly long compared with related compounds. In the crystal, ions are linked through C-H⋯I hydrogen bonds. The crystal studied was a non-merohedral twin with a minor twin domain of 6.56 (5)%.

10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2581, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22065817

RESUMO

The imidazolidine ring in the title compound, C(17)H(18)Cl(2)N(2)O(2), adopts a twist conformation. The observed conformation is stabilized by two intra-molecular O-H⋯N hydrogen bonds, with both N atoms acting as hydrogen-bond acceptors. The phenyl substituents are aligned at 70.0 (1) and 76.6 (1)° with respect to the best plane through the five atoms of the imidazolidine ring. Weak inter-molecular C-H⋯O inter-actions stabilize the crystal packing.

11.
Chem Cent J ; 5: 55, 2011 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-21933409

RESUMO

BACKGROUND: Novel mono N-alkyl quaternary ammonium salts (3a-f) were prepared using the Menschutkin reaction from the cage adamanzane type aminal 1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecane (TATU) and alkyl iodides, such as methyl, ethyl, propyl, butyl, pentyl and hexyl iodide (2a-f), in dry acetonitrile at room temperature. RESULTS: The structures of these new quaternary ammonium salts were established using various spectral and electrospray ionization mass spectrometry (ESI-MS) analyses. Compound (3b) was also analyzed using X-ray crystallography. CONCLUSION: It was noted that alkyl chain length did not significantly affect the reaction because all employed alkyl iodide electrophiles reacted in a similar fashion with the aminal 1 to produce the corresponding mono N-quaternary ammonium salts, which were characterized by spectroscopic and analytical techniques.

12.
Acta Crystallogr C ; 65(Pt 9): o435-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19726855

RESUMO

The title compound, 1,5:3,7-dimethano-1,3,5,7-benzotetrazonine-hydroquinone (2/1), 2C(11)H(14)N(4).C(6)H(6)O(2), crystallizes with the hydroquinone molecule located on a center of inversion. In contrast to other hydroquinone-adamanzane adducts, which form extended hydrogen-bonded networks, in the present case, one hydroquinone molecule is linked to two 1,5:3,7-dimethano-1,3,5,7-benzotetrazonine molecules, forming a 2:1 cluster through O-H...N hydrogen bonds.

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