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1.
Drug Test Anal ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039910

RESUMO

A number of synthetic cannabinoids have been appearing in the recreational drug market for more than a decade. Recent additions are so-called semi-synthetic cannabinoids, and they structurally closely resemble the main psychoactive component of cannabis, Δ9-tetrahydrocannabinol. Knowledge of new (semi-)synthetic cannabinoids is essential to help identify them in authentic forensic case samples. Therefore, the aim of the study was to examine two commercially available electronic cigarette liquid products claiming to contain cannabinoids and characterize the structures of the main compounds. The liquid products were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), and liquid chromatography-high-resolution mass spectrometry (LC-HRMS). In product A, typical cannabinoids (cannabidiol, cannabigerol, and cannabinol) and terpenes (α-caryophyllene and ß-caryophyllene) were identified by comparison with reference materials. An unknown peak was isolated by semi-preparative high-performance LC, analyzed by nuclear magnetic resonance (NMR) spectroscopy, and identified to be Δ9-tetrahydrocannabihexol acetate (Δ9-THCH-O). To the authors' knowledge, this is the first report of the identification of Δ9-THCH-O in commercially available products. Another compound estimated as cannabihexol acetate was also detected. In product B, cannabidiol, cannabinol, α-caryophyllene, and ß-caryophyllene were identified, while two unknown peaks were estimated as tetrahydrocannabidiol isomers. Despite products A and B being labeled to contain "60% HHCPM" and "80% 10-OH-HHC," respectively, no such compounds were detected. The findings of this study could help detect Δ9-THCH-O in case samples and highlight the need to keep monitoring commercial products to identify new drugs, while warning that the package labels cannot be trusted.

2.
J Am Soc Mass Spectrom ; 32(2): 601-605, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33284010

RESUMO

Positional isomers o-, m-, and p-chloromethcathinones (CMCs) and m- and p-bromomethcathinones (BMCs) were effectively differentiated using gas chromatography (GC) and energy-resolved mass spectrometry (ERMS) analyses. GC demonstrated that the free bases of CMC and BMC isomers were simultaneously baseline-separated at a slow column heating rate (5 °C/min) using a conventional low-polar capillary column. ERMS showed that the trifluoroacetyl derivatives of the positional isomers differed in mass spectral abundances of both halophenyl and halobenzoyl cations. Moreover, the logarithmic plots of the abundance ratio of the two cations as a function of the collision energy (CE) exhibited marked differences among the isomers at each CE, following the order of ortho < para < meta for CMCs and para < meta for BMCs. The performed theoretical calculations of dissociation energy agreed well with the ERMS measurements. The GC and ERMS methodologies enabled unambiguous and reliable differentiation of CMC and BMC isomers. The developed approach is expected to significantly contribute to the accurate structural identification of new psychoactive substances in forensic, toxicological, and clinical fields.

3.
Anal Sci ; 31(12): 1325-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26656825

RESUMO

We describe a unique UV-visible absorption spectral property of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (THPP) in the presence of organophosphorus (OP) pesticides. Upon titrating each 16 among total 40 different OP pesticides, the Soret band was significantly red-shifted, and a very intense Q band appeared. They were attributed to the diprotonation of THPP. A suitable solvent for this reaction was determined to be methanol. THPP would become a potential sensor molecule used to detect OP pesticides with high sensitivity in the concentration range of 10(-6) - 10(-4) M.

4.
Nature ; 462(7270): 226-30, 2009 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-19907495

RESUMO

The mucosal immune system forms the largest part of the entire immune system, containing about three-quarters of all lymphocytes and producing grams of secretory IgA daily to protect the mucosal surface from pathogens. To evoke the mucosal immune response, antigens on the mucosal surface must be transported across the epithelial barrier into organized lymphoid structures such as Peyer's patches. This function, called antigen transcytosis, is mediated by specialized epithelial M cells. The molecular mechanisms promoting this antigen uptake, however, are largely unknown. Here we report that glycoprotein 2 (GP2), specifically expressed on the apical plasma membrane of M cells among enterocytes, serves as a transcytotic receptor for mucosal antigens. Recombinant GP2 protein selectively bound a subset of commensal and pathogenic enterobacteria, including Escherichia coli and Salmonella enterica serovar Typhimurium (S. Typhimurium), by recognizing FimH, a component of type I pili on the bacterial outer membrane. Consistently, these bacteria were colocalized with endogenous GP2 on the apical plasma membrane as well as in cytoplasmic vesicles in M cells. Moreover, deficiency of bacterial FimH or host GP2 led to defects in transcytosis of type-I-piliated bacteria through M cells, resulting in an attenuation of antigen-specific immune responses in Peyer's patches. GP2 is therefore a previously unrecognized transcytotic receptor on M cells for type-I-piliated bacteria and is a prerequisite for the mucosal immune response to these bacteria. Given that M cells are considered a promising target for oral vaccination against various infectious diseases, the GP2-dependent transcytotic pathway could provide a new target for the development of M-cell-targeted mucosal vaccines.


Assuntos
Adesinas de Escherichia coli/metabolismo , Antígenos de Bactérias/metabolismo , Células Epiteliais/imunologia , Proteínas de Fímbrias/metabolismo , Imunidade nas Mucosas/imunologia , Glicoproteínas de Membrana/metabolismo , Nódulos Linfáticos Agregados/citologia , Adesinas de Escherichia coli/genética , Adesinas de Escherichia coli/imunologia , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Linhagem Celular , Células Epiteliais/metabolismo , Escherichia coli/imunologia , Escherichia coli/metabolismo , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/imunologia , Proteínas Ligadas por GPI , Glicoproteínas , Células HeLa , Humanos , Intestinos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nódulos Linfáticos Agregados/imunologia , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Salmonella typhimurium/metabolismo , Especificidade por Substrato
5.
Blood ; 110(4): 1215-24, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17519390

RESUMO

Follicular dendritic cells (FDCs) form a reticular FDC network in the lymphoid follicle that is essential for the retention and presentation of native antigens in the form of antigen-antibody immune complexes (ICs) to B cells during secondary immune response. Although the presence of migrating precursors of FDCs has been hypothesized, their entity has not been elucidated. Here we report the identification of murine splenic CD19(-)CD11c(-)CD35(+)B220(+) cells as an inducer of FDC network formation. We demonstrated that CD19(-)-CD11c(-)CD35(+)B220(+) cells, together with stromal cells, had the remarkable ability to form lymphoid-follicle-like structures that contained B220(+)FDC-M1(+) reticular cells originally derived from CD19(-)-CD11c(-)CD35(+)B220(+) cells in the CD35(+) reticulum. Our results indicate that CD19(-)CD11c(-)CD35(+)B220(+) cells function as an inducer of FDC network formation and that the interaction between CD19(-)CD11c(-)CD35(+)B220(+) cells and stromal cells is required to initiate lymphoid follicle formation.


Assuntos
Antígenos CD19/metabolismo , Células Dendríticas Foliculares/citologia , Antígenos Comuns de Leucócito/metabolismo , Receptores de Complemento 3b/metabolismo , Baço/citologia , Animais , Diferenciação Celular , Linhagem da Célula , Células Dendríticas Foliculares/metabolismo , Citometria de Fluxo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imunofenotipagem , Células Matadoras Naturais/classificação , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Células Estromais/citologia , Células Estromais/imunologia , Células Estromais/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/fisiologia
6.
Immunity ; 22(1): 93-104, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664162

RESUMO

Tumor necrosis factor (TNF, TNFalpha) is implicated in various pathophysiological processes and can be either protective, as in host defense, or deleterious, as in autoimmunity or toxic shock. To uncover the in vivo functions of TNF produced by different cell types, we generated mice with TNF ablation targeted to various leukocyte subsets. Systemic TNF in response to lipopolysaccharide was produced mainly by macrophages and neutrophils. This source of TNF was indispensable for resistance to an intracellular pathogen, Listeria, whereas T-cell-derived TNF was important for protection against high bacterial load. Additionally, both T-cell-derived TNF and macrophage-derived TNF had critical and nonredundant functions in the promotion of autoimmune hepatitis. Our data suggest that T-cell-specific TNF ablation may provide a therapeutic advantage over systemic blockade.


Assuntos
Macrófagos/metabolismo , Neutrófilos/metabolismo , Linfócitos T/metabolismo , Fatores de Necrose Tumoral/fisiologia , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Comunicação Celular , Cruzamentos Genéticos , Deleção de Genes , Vetores Genéticos , Listeria/patogenicidade , Fígado/imunologia , Fígado/patologia , Camundongos , Camundongos Transgênicos , Sensibilidade e Especificidade , Linfócitos T/imunologia , Fatores de Necrose Tumoral/imunologia , Fatores de Necrose Tumoral/metabolismo
7.
Eur J Immunol ; 34(3): 859-869, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14991616

RESUMO

To evaluate the in vivo effect of immunosuppressive glucocorticoids on CD4+CD25+ T regulatory cells, we injected dexamethasone (Dex) into BALB/c mice. Administration of Dex enhanced the proportion of CD4+CD25+ cells and the ratio of CD4+CD25+ cells to CD4+CD25- cells in the lymphoid organs, especially in the thymus. This correlates with our in vitro observation that CD4+CD25+ T cells express higher levels of glucocorticoid receptor and Bcl-2, and are therefore more resistant to Dex-mediated cell death than CD4+CD25- T cells. Furthermore, IL-2 selectively protected CD4+CD25+ T cells from Dex-induced cell death, while IL-7 and IL-15 did not exert preferential protective effects. Dex-treated CD4+CD25+ T cells expressed higher levels of intracellular CTLA-4 and surface glucocorticoid-induced TNF receptor than fresh CD4+CD25+ T cells, but still failed to respond to TCR stimulation and inhibited proliferation of CD4+CD25- T cells. These results suggest that, in addition to suppressing cytokine transcription, Dex treatment is permissive for the survival of functional CD4+CD25+ T regulatory cells, and this property may contribute to the anti-inflammatory and immunosuppressive efficacy of glucocorticoids. Our data also suggest that selective protection of CD4+CD25+ T cell from apoptosis may constitute a role in immune tolerance for IL-2.


Assuntos
Apoptose , Linfócitos T CD4-Positivos/imunologia , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Receptores de Interleucina-2/análise , Subpopulações de Linfócitos T/imunologia , Animais , Antígenos CD , Antígenos de Diferenciação/metabolismo , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Antígeno CTLA-4 , Feminino , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Interleucina-10/metabolismo , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Timo/citologia , Timo/efeitos dos fármacos , Timo/imunologia
8.
Blood ; 101(4): 1477-83, 2003 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-12560241

RESUMO

TNF/LTalpha/LTbeta (tumor necrosis factor/lymphotoxin-alpha/lymphotoxin-beta) triple knockout (KO) mice show a significant reduction of dendritic cell (DC) number in the spleen, presumably due to defective recruitment and/or production. To distinguish between these possibilities, DCs were generated from bone marrow (BM) cultures prepared from wild-type (wt) and mutant mice in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). The yield of CD11c(+) major histocompatibility complex (MHC) class II(+) DCs generated from TNF/LTalpha/LTbeta(-/-) BM culture was significantly reduced compared with wt BM culture. In order to further dissect the individual pathways responsible for defective DC properties observed in TNF/LTalpha/LTbeta(-/-) mice, the panel of TNF/LT ligand and receptor single KO mice were used. The production of DCs from BM culture was significantly reduced in TNF(-/-) and TNF receptor (TNFR) p55(-/-) mice, but normal in LTalpha(-/-), LTbeta(-/-), LTbetaR(-/-) mice. Recombinant TNF (rTNF) exogenously added to TNF/LTalpha/LTbeta(-/-) BM cultures could reverse this defect, and blocking antibodies showed partial effect on BM cultures of wt mice. Conversely, numbers of mature DCs in spleen were significantly decreased in LTalpha(-/-), LTbeta(-/-), LTbetaR(-/-) mice, but not in TNF(-/-) and TNFRp55(-/-) mice. These results reveal 2 distinct contributions of TNF/LT cytokines. First, TNF acting through TNF receptor is involved in the development/maturation of DCs in BM progenitor cultures, but this function appears to be redundant in vivo. Second, the microenvironment in peripheral lymphoid organs associated with LTalpha/LTbeta-LTbetaR signaling and chemokine production is critical for recruitment efficiency of DCs, and this pathway is indispensable.


Assuntos
Células Dendríticas/citologia , Linfocinas/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Células da Medula Óssea/citologia , Contagem de Células , Células Cultivadas , Células Dendríticas/imunologia , Citometria de Fluxo , Expressão Gênica , Teste de Cultura Mista de Linfócitos , Linfocinas/deficiência , Linfocinas/genética , Receptor beta de Linfotoxina , Linfotoxina-alfa/deficiência , Linfotoxina-alfa/genética , Linfotoxina-alfa/fisiologia , Linfotoxina-beta , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Knockout , Receptores do Fator de Necrose Tumoral/fisiologia , Proteínas Recombinantes/farmacologia , Baço/citologia , Células-Tronco/citologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética
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