RESUMO
The anterolateral system (ALS) is a major ascending pathway from the spinal cord that projects to multiple brain areas and underlies the perception of pain, itch and skin temperature. Despite its importance, our understanding of this system has been hampered by the considerable functional and molecular diversity of its constituent cells. Here we use fluorescence-activated cell sorting to isolate ALS neurons belonging to the Phox2a-lineage for single-nucleus RNA sequencing. We reveal five distinct clusters of ALS neurons (ALS1-5) and document their laminar distribution in the spinal cord using in situ hybridization. We identify 3 clusters of neurons located predominantly in laminae I-III of the dorsal horn (ALS1-3) and two clusters with cell bodies located in deeper laminae (ALS4 & ALS5). Our findings reveal the transcriptional logic that underlies ALS neuronal diversity in the adult mouse and uncover the molecular identity of two previously identified classes of projection neurons. We also show that these molecular signatures can be used to target groups of ALS neurons using retrograde viral tracing. Overall, our findings provide a valuable resource for studying somatosensory biology and targeting subclasses of ALS neurons.
RESUMO
STUDY DESIGN: Focus group qualitative study. OBJECTIVES: To explore factors affecting adherence to behaviours appropriate for the prevention of pressure injuries (PIs) in people with spinal cord injury (SCI) in Malaysia. SETTING: University Hospital, Malaysia METHODS: Four sets of focus group interviews were conducted, each with 5-10 participants, totalling 30 people with SCI. A trained interviewer used structured interviews designed to explore participants' experiences of complying with recommended behaviours for the prevention of PIs. All interviews were digitally recorded, transcribed, and analysed utilising thematic analysis. RESULTS: The factors that affected participants' adherence are classified into four main themes: (a) educational aspects, (b) internal drive, (c) social and environmental factors, and (d) post-SCI physiological changes. CONCLUSIONS: This qualitative study provides initial exploratory evidence regarding the thoughts, experience, and opinions pertaining to PI preventive behaviours within the Malaysian SCI population. The emerging themes contribute to an in-depth understanding of the competency of the Malaysian healthcare system in PI prevention, personal and societal factors influenced by the socio-demographic backgrounds, and disease-related factors that influence the adherence to such preventive interventions.
Assuntos
Úlcera por Pressão , Traumatismos da Medula Espinal , Humanos , Grupos Focais , Malásia , Pesquisa Qualitativa , Traumatismos da Medula Espinal/complicações , Úlcera por Pressão/prevenção & controleRESUMO
A new prenylated flavone, named artoindonesianin L (1), was isolated from Artocarpus rotunda (Hout) Panzer (Moraceae). Its structure was elucidated as on the basis of spectroscopic evidence. Along with this new compound, four known phenolic compounds were also isolated from this plant and identified as artonins M (2) and E (3), cycloartobiloxanthone (4) and artonin O (5). All these compounds showed significant cytotoxicity against murine P388 leukemia cells.
Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Moraceae , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos/uso terapêutico , Flavonoides/uso terapêutico , Concentração Inibidora 50 , Camundongos , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
Two new alkaloids, norpandamarilactonine-A (1) and -B (2), which have a pyrrolidinyl-alpha,beta-unsaturated gamma-lactone moiety as in the known pandamarilactonine alkaloids, were isolated from the leaves of Pandanus amaryllifolius. Their structures were determined by spectroscopic analysis and total synthesis.
Assuntos
Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae , Lactonas/isolamento & purificação , Magnoliopsida/química , Pirrolidinas/isolamento & purificação , Alcaloides/química , Catálise , Cromatografia , Cristalografia por Raios X , Lactonas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Folhas de Planta/química , Plantas Medicinais/química , Pirrolidinas/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Estereoisomerismo , TailândiaRESUMO
The small intestinal damage induced by the methotrexate (MTX) treatment results in malabsorption and diarrhea. The fluoresceinated methotrexate (F-MTX) may possibly be useful to study such effects of MTX on the small intestine. The purpose of this study is to characterize the transport of F-MTX in the small intestine in order to use it as a membrane transport and cellular marker of MTX. The transport of F-MTX in the rat small intestine (jejunum) was examined in the in vitro everted segments of the intestine. The uptake was pH-dependent and showed a maximal effect at pH 6.0, which was the same as the results of MTX previously reported. Further, it was temperature-dependent and was inhibited by metabolic inhibitors, dinitrophenol and sodium azide, and by MTX. The transport kinetics at pH 6.0 in the mucosal solution and at pH 7.4 in the serosal solution was saturable with Km of 0.48 +/- 0.23 microM and Vmax of 0.66 +/- 0.24 pmol/cm/min and in addition, the passive diffusion was observed there. These results suggested that the transport of F-MTX was energy-dependent and was mediated by the same transporter as that of MTX, although, in addition to it, other transport mechanism might contribute to the F-MTX transport. Therefore F-MTX will be of great use to investigate the MTX transport system in the normal and diseased states of small intestine, using various fluorescence techniques like visualization of membrane-associated transport proteins.
Assuntos
Corantes Fluorescentes/farmacocinética , Jejuno/metabolismo , Metotrexato/farmacocinética , Animais , Transporte Biológico , Temperatura Baixa , Dinitrofenóis/farmacologia , Concentração de Íons de Hidrogênio , Jejuno/efeitos dos fármacos , Masculino , Metotrexato/análogos & derivados , Ratos , Ratos Wistar , Azida Sódica/farmacologiaRESUMO
Two new prenylated compounds, the benzoquinone atrovirinone (1) and the depsidone atrovirisidone (2), were isolated from the roots of Garcinia atroviridis. Their structures were determined on the basis of the analysis of spectroscopic data. While compound 2 showed some cytotoxicity against HeLa cells, both compounds 1 and 2 were only mildly inhibitory toward Bacillus cereus and Staphylococcus aureus.
Assuntos
Anti-Infecciosos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Benzoquinonas/isolamento & purificação , Lactonas/isolamento & purificação , Plantas Medicinais/química , Adolescente , Antibacterianos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Aspergillus ochraceus/efeitos dos fármacos , Bacillus cereus/efeitos dos fármacos , Benzoquinonas/química , Benzoquinonas/farmacologia , Candida albicans/efeitos dos fármacos , Colchicina/farmacologia , Doxorrubicina/farmacologia , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células HeLa , Humanos , Lactonas/química , Lactonas/farmacologia , Espectroscopia de Ressonância Magnética , Malásia , Estrutura Molecular , Raízes de Plantas/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Staphylococcus aureus/efeitos dos fármacos , Estreptomicina/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
Three new indole alkaloids with methyl chanofruticosinates skeletal system, viz., methyl 12-methoxy-N1-decarbomethoxychanofruticosinate, methyl 12-methoxychanofruticosinate and methyl 11,12-dimethoxychanofruticosinate, in addition to methyl 11,12-methylenedioxy-N1-decarbomethoxychanofruticosinate, have been isolated from the leaves of Kopsia flavida Blume. The structures of these three new indole alkaloids were assigned by NMR spectral data using various 2D-techniques.
Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Indóis/química , Magnoliopsida/química , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Malásia , Folhas de Planta/química , Plantas Medicinais/químicaRESUMO
A novel alkaloid, lycoposerramine-A (1), which has a 1,2,4-oxadiazolidin-5-one residue in the molecule, was isolated from the club moss Lycopodium serratum Thunb. The structure was determined by spectroscopic and X-ray analyses. [structure: see text]
Assuntos
Alcaloides/química , Lycopodiaceae/química , Oxidiazóis/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura MolecularRESUMO
The leaves of a tropical plant, Mitragyna speciosa Korth. (Rubiaceae), have been traditionally used as a substitute for opium. By phytochemical studies on the constituents of the plant growing in Thailand as well as in Malaysia, several 9-methoxy-Corynanthe-type monoterpenoid indole alkaloids including new natural products were isolated. The structures of these new compounds were elucidated by the modern spectroscopic methods and/or chiral-total syntheses. The chiral total synthesis of (-)-mitragynine, a major component of this plant, was achieved. Potent opioid agonistic properties of mitragynine, which acts on mu- and delta-opioid subtype receptors, and of mitragynine pseudoindoxyl, whose analgesic activity is more potent than that of morphine, were clarified in in vitro experiments. The essential structural features in mitragynine for revealing the analgesic activity were elucidated by pharmacological evaluation of the natural and synthetic mitragynine derivatives.
Assuntos
Alcaloides , Analgésicos Opioides , Indóis , Plantas Medicinais/química , Alcaloides/química , Alcaloides/isolamento & purificação , Indóis/química , Indóis/isolamento & purificação , Ópio , Receptores Opioides/agonistas , Relação Estrutura-AtividadeRESUMO
A new type of natural product, idenburgene (1), was isolated from Crytocarya idenburgensis, and its unique structure was elucidated. Four known compounds, 3-hydroxy-5-methoxystilbene (2), 2',6'-dihydroxy-4'-methoxydihydrochalcone (3), stigmast-4-ene-3-one, and beta-sitosterol were also isolated and identified.
Assuntos
Lauraceae/química , Estilbenos/química , Indonésia , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Plantas Medicinais , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
The structure and absolute configuration of an alpha-pyrone isolated from Cryptocarya strictifolia was elucidated as 6R-(4'R,6'R-dihydroxy-8'-phenyloct-1'-enyl)-5,6-dihydro-2H-pyran-2 -one. Pinocembrin and lysicamine were also isolated.
Assuntos
Magnoliopsida/química , Pironas/isolamento & purificação , Estrutura Molecular , Pironas/química , Análise EspectralRESUMO
A new gluco indole alkaloid, 3,4-dehydro-5-carboxystrictosidine, was obtained from Peruvian Uña de Gato (Cat's Claw, original plant: Uncaria tomentosa) together with two known gluco indole alkaloids. This compound was the first example of isolation of a gluco monoterpenoid indole alkaloid having a 3,4-dihydro-beta-carboline ring system from nature. A characteristic feature of the compound was the quick replacement of the methylene hydrogens on C-14 with deuterium that was observed when it was dissolved in CD3OD. We demonstrated a similar proton-deuterium exchange on a model compound, 1-methyl-3,4-dihydro-gamma-carboline, in CD3OD solution.
Assuntos
Alcaloides/isolamento & purificação , Indóis/isolamento & purificação , Rubiaceae/química , Alcaloides/química , Indóis/química , Estrutura Molecular , Análise EspectralRESUMO
The methanol extract of Tabernaemontana penduliflora was found to appreciably inhibit [3H]-estradiol binding to estrogen receptors. Activity-guided fractionation led to the isolation of two known alkaloids, 10-hydroxycoronaridine (1) and its 10-O-methyl ether, voacangine (2). These alkaloids together with other related alkaloids were tested for their estrogenic activities. Among these molecules, 1 was found to be the most potent estrogen agonist and is distinctly more active than genistein.
Assuntos
Estrogênios não Esteroides/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Plantas/química , Divisão Celular/efeitos dos fármacos , Estrogênios não Esteroides/química , Estrogênios não Esteroides/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Estrutura Molecular , Células Tumorais CultivadasRESUMO
A new xanthone derivative, artoindonesianin C (1), was isolated from Artocarpus teysmanii, together with two known prenylated flavonoids, cycloartobiloxanthone and artonin J. The structure of artoindonesianin C (1) was determined on the basis of MS and NMR evidence and by comparison with known related compounds.
Assuntos
Flavonoides/isolamento & purificação , Plantas Medicinais/química , Animais , Artemia , Bombyx , Flavonoides/química , Flavonoides/farmacologia , Técnicas In Vitro , Dose Letal Mediana , Leucina/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Epiderme Vegetal/química , Raízes de Plantas/química , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
The effects of hirsutine, an indole alkaloid from Uncaria rhynchophylla MIQ. JACKSON with antihypertensive, negative chronotropic and antiarrhythmic activity, and its C3 structural epimer, dihydrocorynantheine, on membrane potentials of rabbit sino-atrial node and guinea-pig right ventricle and left atrium were studied with microelectrode techniques. In sino-atrial node preparations, hirsutine and dihydrocorynantheine (0.1 microM to 10 microM) concentration-dependently increased cycle length, decreased slope of the pacemaker depolarization (phase 4 depolarization), decreased maximum rate of rise and prolonged action potential duration. In atrial and ventricular preparations, both compounds (0.1 microM to 30 microM) concentration-dependently decreased maximum rate of rise and prolonged action potential duration. These results indicate that hirsutine and dihydrocorynantheine have direct effects on the action potential of cardiac muscle through inhibition of multiple ion channels, which may explain their negative chronotropic and antiarrhythmic activity.
Assuntos
Potenciais de Ação/efeitos dos fármacos , Alcaloides/farmacologia , Coração/efeitos dos fármacos , Animais , Anti-Hipertensivos/farmacologia , Função Atrial , Função do Átrio Esquerdo/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Feminino , Cobaias , Coração/fisiologia , Átrios do Coração/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Técnicas In Vitro , Masculino , Microeletrodos , Coelhos , Nó Sinoatrial/efeitos dos fármacos , Nó Sinoatrial/fisiologia , Estereoisomerismo , Vasodilatadores/farmacologia , Função Ventricular , Função Ventricular Direita/efeitos dos fármacosRESUMO
A new anthraquinone, 2-hydroxymethyl-10-hydroxy-1,4-anthraquinone (1), was isolated from Hedyotis herbacea along with three other known derivatives: 1,4-dihydroxy-2-hydroxymethylanthraquinone (2); 2, 3-dimethoxy-9-hydroxy-1,4-anthraquinone; and 1,4-dihydroxy-2, 3-dimethoxyanthraquinone. The structure of 1 was determined based on analysis of its spectroscopic data.
RESUMO
We have previously elucidated the opiate-like action of mitragynine, an active principle isolated from the Thai medicinal plant Mitragyna speciosa. In the present study, effects of the related compound, mitragynine pseudoindoxyl on electrically stimulated contraction in guinea pig ileum and mouse vas deferens, and on its binding affinity in the guinea pig brain membranes were studied. Mitragynine pseudoindoxyl inhibited the electrically stimulated ileum and mouse vas deferens contractions in a concentration-dependent manner. In the ileum, the effective concentration is in an nM order, being nearly equivalent to reported concentrations of the micro-opioid receptor agonist [D-Ala2, Met-Phe4, Gly-ol5] enkephalin (DAMGO), and is 100- and 20-fold smaller than those of mitragynine and morphine, respectively. In the vas deferens, it is 35-fold smaller than that of morphine. The inhibitory action of mitragynine pseudoindoxyl in the ileum was antagonized by the non-selective opioid receptor antagonist naloxone and the micro-receptor antagonist naloxonazine. It was also antagonized by the delta-receptor antagonist naltrindole in the vas deferens. Mitragynine pseudoindoxyl showed a similar binding affinity to DAMGO and naltrindole at micro- and delta-receptors, respectively. However, the affinity at kappa-receptors was negligible. The present study demonstrates that mitragynine pseudoindoxyl, a novel alkaloid structurally different from other opioid agonists, acts on opioid receptors, leading to a potent inhibition of electrically stimulated contraction in the ileum through the micro-receptors and in mouse vas deferens through delta-receptors.
Assuntos
Analgésicos/farmacologia , Plantas Medicinais/química , Receptores Opioides/agonistas , Alcaloides de Triptamina e Secologanina/farmacologia , Animais , Ligação Competitiva , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Estimulação Elétrica , Cobaias , Íleo/efeitos dos fármacos , Íleo/fisiologia , Técnicas In Vitro , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/inervação , Músculo Liso/fisiologia , Naloxona/análogos & derivados , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Receptores Opioides/metabolismo , Tailândia , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologiaRESUMO
The non-nucleoside reverse transcriptase (RT) inhibitor RD4-2217 is a thiadiazole derivative that has proved to be a highly potent and selective inhibitor of human immunodeficiency virus type 1 (HIV-1) replication in vitro. In this study we examined genotypic and phenotypic characteristics of RD4-2217-resistant mutants that have been obtained by serial passage of HIV-1 in MT-4 cells in the presence of increasing concentrations (0.05, 0.25, 1 and 10 microM) of the compound. The strains obtained, III(B/2217RE/0.05) and III(B/2217RE/0.25,) were two- and 15-fold resistant to RD4-2217, respectively, whereas III(B/2217RE/1) and III(B/2217RE/10) displayed 161- and >238-fold resistance, respectively. Both III(B/2217RE/1) and III(B/2217RE/10) had two amino acid substitutions, V1891 and T2401, in the RT. Furthermore, RD4-2217 did not inhibit the replication of an HIV-1 molecular clone, which had the same mutation, at concentrations up to 10 microM, indicating that the V1891 plus T2401 mutation confers high-level resistance to RD4-2217. Interestingly, the replicability of III(B2217RE/1) and III(B/2217RE/10) appeared to be lower than that of wildtype III(B) in MT-4 cells, suggesting that the V1891 plus T2401 mutation may impair the enzymatic activity of HIV-1 RT.
Assuntos
Fármacos Anti-HIV/farmacologia , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Tiadiazóis/farmacologia , Linhagem Celular , Resistência Microbiana a Medicamentos , Genótipo , HIV-1/genética , HIV-1/fisiologia , Humanos , Fenótipo , Replicação Viral/efeitos dos fármacosRESUMO
We previously reported that corymine, an alkaloid extracted from the leaves of Hunteria zeylanica native to Thailand, inhibited glycine-induced chloride current using a receptor expression model of Xenopus oocytes. In this study, we investigated the mechanism underlying the inhibitory action of this alkaloid on glycine current using the same model. Corymine inhibited glycine current in a noncompetitive fashion. Co-application with strychnine, a competitive glycine receptor antagonist, or 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), a Cl- channel blocker, corymine decreased the ED50 value of strychnine, but did not change that of DIDS. Moreover, the inhibitory effects of corymine and either strychnine or DIDS were additive. The desensitization phase of glycine current showed two exponentials and corymine preferentially inhibited the fast component, whereas strychnine affected both of them to the same extent and DIDS preferentially inhibited the slow component. When these drugs were applied repeatedly, the inhibitory effects of corymine and strychnine were not use-dependent and reversible, while the effect of DIDS was use-dependent and irreversible. The inhibitory effect of corymine on gamma-aminobutyric acid (GABA) current was less potent than the effect on glycine current, while this alkaloid failed to affect acetylcholine and serotonin currents. These results demonstrate that corymine inhibits glycine-gated CI- channels by interacting with the site different from that of DIDS.
Assuntos
Alcaloides/farmacologia , Canais de Cloreto/antagonistas & inibidores , Cloretos/metabolismo , Antagonistas GABAérgicos/farmacologia , Glicinérgicos/farmacologia , Oócitos/efeitos dos fármacos , Receptores de Glicina/antagonistas & inibidores , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Separação Celular , Relação Dose-Resposta a Droga , Interações Medicamentosas , Glicina/metabolismo , Transporte de Íons/efeitos dos fármacos , Oócitos/metabolismo , Estricnina/farmacologia , Xenopus laevisRESUMO
We examined the effects of 4 corymine-related compounds on glycine-induced chloride current in Xenopus oocytes. Dihydrocorymine, N-demethyl-3-epi-dihydrocorymine and deformylcorymine dose-dependently decreased the glycine current with IC50 values of 34, 37 and 55 microM, respectively. The effect of these compounds on the glycine current was more potent than that of pleiocarpamine (IC50 > 1 mM). N-demethyl-3-epi-dihydrocorymine and dihydrocorymine, at 100 microM, also decreased the gamma-aminobutyric acid-induced current by 65% and 22%, respectively, whereas deformylcorymine and pleiocarpamine failed. The inhibitory action of deformylcorymine on the glycine current was noncompetitive. These results suggest that deformylcorymine is a novel specific noncompetitive glycine receptor antagonist. The structure-activity relationship of these compounds was discussed.