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1.
Nat Commun ; 15(1): 2744, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553478

RESUMO

Assigning single cell transcriptomes to cellular lineage trees by lineage tracing has transformed our understanding of differentiation during development, regeneration, and disease. However, lineage tracing is technically demanding, often restricted in time-resolution, and most scRNA-seq datasets are devoid of lineage information. Here we introduce Gene Expression Memory-based Lineage Inference (GEMLI), a computational tool allowing to robustly identify small to medium-sized cell lineages solely from scRNA-seq datasets. GEMLI allows to study heritable gene expression, to discriminate symmetric and asymmetric cell fate decisions and to reconstruct individual multicellular structures from pooled scRNA-seq datasets. In human breast cancer biopsies, GEMLI reveals previously unknown gene expression changes at the onset of cancer invasiveness. The universal applicability of GEMLI allows studying the role of small cell lineages in a wide range of physiological and pathological contexts, notably in vivo. GEMLI is available as an R package on GitHub ( https://github.com/UPSUTER/GEMLI ).


Assuntos
Perfilação da Expressão Gênica , Software , Humanos , Linhagem da Célula/genética , Análise de Sequência de RNA , Análise da Expressão Gênica de Célula Única , Análise de Célula Única
2.
J Pharm Pharm Sci ; 12(1): 116-28, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19470296

RESUMO

PURPOSE: Transient receptor potential vanilloid-3 (TRPV3) is a thermo-sensitive ion channel expressed in skin keratinocytes and in a variety of neural cells. It is activated by warmth as well as monoterpenoids including camphor, menthol, dihydrocarveol and 1,8-cineol. TRPV3 is described as a putative nociceptor and previous studies revealed sensitization of the channel during repeated short-term stimulation with different agonists. In the present investigation TRPV3 was transiently expressed in either Xenopus oocytes or HEK293 cells. Whole-cell voltage-clamp techniques were used to characterize the behavior of TRPV3 when challenged with different agonists. METHODS: Similarly, a human keratinocyte-derived cell line (HaCaT cells) was used to monitor the behavior of native TRPV3 when challenged with different agonists. RESULTS: We report here that prolonged exposure (5-15 minutes) of monoterpenoids results in agonist-specific desensitization of TRPV3. Long-term exposure to camphor and 1,8-cineol elicits desensitizing currents in TRPV3 expressing oocytes, whereas the non-terpenoid agonist 2-APB induces sustained currents. Agonist-specific desensitization of endogenous TRPV3 was also found in HaCaT cells, which may be taken as a representative for the native system. Terpenoids have a long history of use in therapeutics, pharmaceuticals and cosmetics but knowledge about underpinning molecular mechanisms is incomplete. Our finding on agonist-induced desensitization of TRPV3 by some monoterpenoids displays a novel mechanism through which TRP channels could be functionally modulated. CONCLUSION: Desensitization of TRPV3 channels might be the molecular basis of action for some of the medicinal properties of camphor and 1,8-cineol.


Assuntos
Potenciais da Membrana/efeitos dos fármacos , Monoterpenos/farmacologia , Canais de Cátion TRPV/agonistas , Animais , Humanos , Oócitos , Canais de Cátion TRPV/metabolismo , Xenopus laevis
4.
Transplant Proc ; 40(4): 974-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18555093

RESUMO

Acute cardiac allograft rejection remains a major cause of morbidity and mortality after heart transplantation and predisposes for the development of graft vasculopathy. The aim of this study was to investigate the immunomodulatory effect of preconditioning of the donor and recipient with medical ozone (O(3)/O(2)) on acute allograft rejection. Minimizing the initial ischemia-reperfusion injury may result in a reduction of graft vasculopathy and ameliorate long-term outcomes after cardiac transplantation. Lewis rats were challenged with Wistar-Furth cardiac allograft. In donor and recipient animals a medical ozone (O(3)/O(2))-pneumoperitoneum was induced by single (1x) or repetitive (5x) insufflation (concentration: 50 microg/mL, 80 mL/kg body weight) of medical ozone intraperitoneally. Without immunomodulatory therapy (n = 11) cardiac allograft survival was 5.9 +/- 0.9 days. Preconditioning with medical ozone alone (single bolus as well as repetitive administration, n = 7) of the donor and recipient animals prolonged cardiac allograft survival significantly to 7.6 +/- 1.4 days (P < .05), without any adjunctive immunosuppressive therapy. In this pilot study, the intraperitoneal administration of ozone in donor and recipient animals protected from ischemia-reperfusion injury, reduced the immunogenicity of the graft, and prolonged cardiac allograft survival. Further studies are warranted to elucidate the underlying mechanisms and--more important--to investigate the effect on the development of graft vasculopathy, the major obstacle to long-term graft and patient survivals.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transplante de Coração/fisiologia , Imunossupressores/uso terapêutico , Ozônio/uso terapêutico , Transplante Homólogo/fisiologia , Animais , Masculino , Modelos Animais , Ratos , Ratos Endogâmicos WF , Condicionamento Pré-Transplante/métodos
5.
Injury ; 49(10): 1822-1829, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30054047

RESUMO

Hand injuries are common and can result in a long time off work. To analyse and identify factors affecting time of work, a holistic view on patients is needed. World Health Organization's International Classification of Functioning, Disability and Health (ICF) with its bio-psycho-social perspective provides such a holistic view. The purpose of this study is to analyse time off work in patients with traumatic hand injuries and to identify factors affecting time off work from a bio-psycho-social perspective. We used factors derived from the ICF Core Set for Hand Conditions to predict time off work by applying Cox regression analyses and Kaplan-Meier method using data of a multicentre prospective study in nine German Level 1 hand trauma centres. In total, 231 study participants with a broad range of hand injuries were included. From these, 178 patients (77%) returned to work within 200 days. Impairments in mobility of joint functions and sensory functions related to temperature and other stimuli as well as higher hand strain at work led to extended time off work. Gender, fine hand use and employment status additionally influenced time off work in sub-models. Our results demonstrate that a bio-psycho-social perspective is recommended when investigating time off work.


Assuntos
Absenteísmo , Pessoas com Deficiência/psicologia , Traumatismos da Mão/psicologia , Traumatismos da Mão/reabilitação , Saúde Holística , Retorno ao Trabalho , Adulto , Avaliação da Deficiência , Pessoas com Deficiência/reabilitação , Emprego , Feminino , Traumatismos da Mão/classificação , Traumatismos da Mão/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psicometria , Recuperação de Função Fisiológica/fisiologia , Retorno ao Trabalho/psicologia , Retorno ao Trabalho/estatística & dados numéricos , Fatores de Risco , Fatores Socioeconômicos
6.
Br J Pharmacol ; 151(4): 530-40, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17420775

RESUMO

BACKGROUND AND PURPOSE: Transient receptor potential (TRP) V3 is a thermosensitive ion channel expressed predominantly in the skin and neural tissues. It is activated by warmth and the monoterpene camphor and has been hypothesized to be involved in skin sensitization. A selection of monoterpenoid compounds was tested for TRPV3 activation to establish a structure-function relationship. The related channel TRPM8 is activated by cool temperatures and a number of chemicals, among them the monoterpene (-)-menthol. The overlap of the receptor pharmacology between the two channels was investigated. EXPERIMENTAL APPROACH: Transfected HEK293 cells were superfused with the test substances. Evoked currents were measured in whole cell patch clamp measurements. Dose-response curves for the most potent agonists were obtained in Xenopus laevis oocytes. KEY RESULTS: Six monoterpenes significantly more potent than camphor were identified: 6-tert-butyl-m-cresol, carvacrol, dihydrocarveol, thymol, carveol and (+)-borneol. Their EC(50) is up to 16 times lower than that of camphor. All of these compounds carry a ring-located hydroxyl group and neither activates TRPM8 to a major extent. CONCLUSIONS AND IMPLICATIONS: Terpenoids have long been recognized as medically and pharmacologically active compounds, although their molecular targets have only partially been identified. TRPV3 activation may be responsible for several of the described effects of terpenoids. We show here that TRPV3 is activated by a number of monoterpenes and that a secondary hydroxyl-group is a structural requirement.


Assuntos
Monoterpenos/farmacologia , Canais de Cátion TRPV/agonistas , Animais , Células Cultivadas , Desenho de Fármacos , Feminino , Humanos , Relação Estrutura-Atividade , Canais de Cátion TRPM/agonistas , Xenopus laevis
8.
Am J Transplant ; 7(4): 789-98, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17391124

RESUMO

Sanglifehrin A (SFA) is a novel compound with unsurpassed cyclophilin-binding affinity, but relatively low direct antilymphocytic activity. Here, we report the capacity of SFA to selectively inhibit key dendritic cell (DC) functions in vivo and to suppress acute and chronic heart allograft rejection. We show that in vivo, SFA profoundly decreases DC receptor-mediated endocytosis and macropinocytosis and DC-T-cell allostimulatory activity. Furthermore, SFA abrogates >90% of IL-12p70 production in vivo while having no significant effect on IL-10 and TNF-alpha production. In a rat vascularized heart transplant model, SFA alone did not prevent graft rejection and rejection occurred within 23 days after low-dose CsA, whereas addition of SFA to low-dose CsA promoted long-term graft survival (median survival time >100 days; p = 0.0007). With respect to chronic rejection, SFA + CsA almost completely prevented graft arteriosclerosis compared to animals treated with CsA alone and controls. We propose that SFA represents a novel class of immunophilin-binding immunosuppressants with high activity against DCs and the development of graft vasculopathy in CsA-treated recipients.


Assuntos
Ciclosporina/uso terapêutico , Células Dendríticas/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/fisiologia , Transplante de Coração/imunologia , Transferência Adotiva , Animais , Antígenos de Superfície/análise , Células Dendríticas/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Imunossupressores/uso terapêutico , Lactonas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos WF , Compostos de Espiro/uso terapêutico , Transplante Homólogo
9.
Insect Mol Biol ; 11(4): 299-306, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12144694

RESUMO

Insect hindgut and Malpighian tubule (HMT) tissues regulate the contents of the haemolymph through the excretion of waste products and the specific reabsorption of nutrients. As such, they perform a role that is essential for survival and may contain molecular targets for insect control strategies. In order to discover genes expressed in the HMT tissues of the cat flea, Ctenocephalides felis, expressed sequence tags (ESTs) were generated from an unsubtracted HMT cDNA library and from a subtracted HMT cDNA library that had been enriched for HMT-specific cDNAs. A total of 4844 ESTs were analysed from both libraries: 3657 from the subtracted library and 1187 from the unsubtracted library. Of the 1418 distinct ESTs identified from both libraries, 953 had significant similarity to other sequences reported in the GenBank database. A comparison of the results from the two libraries confirmed that the percentages of genes likely to be involved with metabolism, cell structure, and digestion were reduced by the subtraction procedure, whereas genes likely to be involved with ion transport were enriched. Analysis of the prevalence of three individual cDNAs in each library revealed that the actin cDNA was reduced in the subtracted library whereas the cDNAs encoding allantoinase and a peritrophin-like protein were greatly enriched in the subtracted library. Northern blot analysis demonstrated that the actin cDNA was expressed in both the HMT and carcass tissues, whereas the allantoinase and peritrophin-like cDNAs were detected exclusively in the HMT tissues. In total, 97 distinct ESTs that appear to encode proteins involved with ion transport were analysed. Some of these proteins may be directly involved with diuresis or the specific reabsorption of salts and nutrients, and thus may be potential molecular targets for flea control strategies.


Assuntos
DNA Complementar/genética , Etiquetas de Sequências Expressas , Sifonápteros/genética , Animais , Sequência de Bases , Northern Blotting , DNA Complementar/química , Feminino , Biblioteca Gênica , Canais Iônicos/genética , Masculino , Dados de Sequência Molecular , RNA Mensageiro/química , RNA Mensageiro/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Sifonápteros/metabolismo
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