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1.
Proc Natl Acad Sci U S A ; 120(52): e2312962120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38109547

RESUMO

After 500 y of colonizing the forest-steppe area northwest of the Black Sea, on the territories of what is today Moldova and Ukraine, Trypillia societies founded large, aggregated settlements from ca. 4150 BCE and mega-sites (>100 ha) from ca. 3950 BCE. Covering up to 320 ha and housing up to 15,000 inhabitants, the latter were the world's largest settlements to date. Some 480 δ13C and δ15N measurements on bones of humans, animals, and charred crops allow the detection of spatio-temporal patterns and the calculation of complete agricultural Bayesian food webs for Trypillia societies. The isotope data come from settlements of the entire Trypillia area between the Prut and the Dnieper rivers. The datasets cover the development of the Trypillia societies from the early phase (4800-4200/4100 BCE), over the agglomeration of mega-sites (4200/4100-3650 BCE), to the dispersal phase (3650-3000 BCE). High δ15N values mostly come from the mega-sites. Our analyses show that the subsistence of Trypillia mega-sites depended on pulses cultivated on strongly manured (dung-)soils and on cattle that were kept fenced on intensive pastures to easy collect the manure for pulse cultivation. The food web models indicate a low proportion of meat in human diet (approximately 10%). The largely crop-based diet, consisting of cereals plus up to 46% pulses, was balanced in calories and indispensable amino acids. The flourishing of Europe's first mega-populations depended on an advanced, integral mega-economy that included sophisticated dung management. Their demise was therefore not economically, but socially, conditioned [Hofmann et al., PLoS One. 14, e0222243 (2019)].


Assuntos
Agricultura , Isótopos , Animais , Humanos , Bovinos , Teorema de Bayes , Produtos Agrícolas , Produção Agrícola , Esterco/análise , Isótopos de Carbono/análise
2.
J Leukoc Biol ; 114(2): 180-186, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37075217

RESUMO

Chitin is a highly abundant N-acetylglucosamine polysaccharide that has been linked to immune responses in the context of fungal infections and allergic asthma, especially to T helper 2 immune responses. Unfortunately, due to the frequent use of crude chitin preparations of unknown purity and degree of polymerization, there is still great uncertainty about how chitin activates different parts of the human immune system. We recently identified chitin oligomers of 6 N-acetylglucosamine units as the smallest immunologically active chitin motif and the innate immune receptor TLR2 as a primary chitin sensor on human and murine myeloid cells, but the response of further immune cells (e.g. lymphoid cells) to oligomeric chitin has not been investigated. Our analysis of primary human immune cells now shows that chitin oligomers activate immune responses of both innate and adaptive lymphocytes: notably, chitin oligomers activated natural killer cells but not B lymphocytes. Moreover, chitin oligomers induced maturation of dendritic cells and enabled potent CD8+ T-cell recall responses. Our results suggest that chitin oligomers not only trigger immediate innate responses in a limited range of myeloid cells but also exert critical activities across the entire human immune system. This highlights chitin oligomer immune activation as an interesting and broadly applicable potential target for both adjuvant development and therapeutic interference in chitin-mediated pathologies.


Assuntos
Acetilglucosamina , Quitina , Humanos , Animais , Camundongos , Quitina/farmacologia , Células Matadoras Naturais , Linfócitos T CD8-Positivos , Apresentação de Antígeno , Imunidade Inata
3.
J Microsc ; 286(2): 160-167, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35229880

RESUMO

Composition and microstructure of four Viennese scagliola samples, originating from the early 18th to early 20th centuries, were analysed by different methods of microscopy. Results indicate a similar composition in all samples; only minor differences could be observed in the porosity and grain-size-distribution. While, the calcium sulphate raw material was fired at low temperatures (<200°C), the presumable presence of anhydrite II in two samples may indicate hot spots (200-300°C) during the calcination. To achieve 'marble-like' patterns mineral pigments were used to dye the ground mass. The first results show that scagliola surfaces of this study were produced by using the same or very similar technology between the 18th and early 20th centuries. The present study focuses on scagliola interiors in Vienna, Austria from different stylistic periods between the early 18th and early 20th centuries. Scagliola, also called stucco marble, imitates natural stone. It is produced by a mixture of gypsum (CaSO4 ·2H2 O), different pigments, animal glue and water. In the history of interior design, the material played an important role in the 18th and 19th centuries in Central Europe. The aim of the research was a detailed investigation of four selected samples in order to identify the raw materials and manufacturing technology of the stucco marbles used over time in Vienna. As a first step thin sections (i.e. polished, transparent samples with a thickness of 0.03 mm) were prepared from the samples and analysed by different microscopic techniques. All samples showed similarities in their bulk properties, but detailed investigations revealed also some differences in their mineralogical composition. The gypsum binders contained typical air voids and so-called secondary pores which were formed by dissolving larger binder-related particles during the preparation of the mixture. The macroporosity (i.e. the amount of the pores in the samples which are larger than 0.01 mm) measured on microscopic images varied in a narrow range between 14.1% and 19.3%. The raw materials of all samples were fired at relatively low temperatures (i.e. below 200°C), but in two samples we could also determine a few anhydrite (CaSO4 ) crystals that normally form at higher temperatures in the kiln. This indicates that the distribution of temperature in the kiln was heterogeneous during the firing process. The amount and appearance of some minor mineral constituents such as dolomite (CaMg[CO3 ]2 ) and celestine (SrSO4 ) suggest that they were naturally occurred in the raw material and not deliberately added to the binder as a filling material. To achieve different colour hues and imitate natural stone surfaces, fine-grained mineral pigments and charcoal powder were used. Although we have no distinct information about the gypsum sources of these stucco marbles, several small historical gypsum quarries existed southwest of Vienna. Some of them were already in operation in the 16th century, thus a local gypsum occurrence used as a raw material is very probable. Due to the fact that the main features of the analysed samples were very similar, we assume that the scagliola surfaces of this study were produced by using the same or very similar technology between the 18th and early 20th centuries.


Assuntos
Sulfato de Cálcio , Microscopia , Carbonato de Cálcio/química , Sulfato de Cálcio/química , Minerais , Temperatura
4.
Front Neurosci ; 15: 727527, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34588950

RESUMO

Patients with a lower limb amputation rely more on visual feedback to maintain balance than able-bodied individuals. Altering this sensory modality in amputees thus results in a disrupted postural control. However, little is known about how lower limb amputees cope with augmented visual information during balance tasks. In this study, we investigated how unilateral transfemoral amputees incorporate visual feedback of their center of pressure (CoP) position during quiet standing. Ten transfemoral amputees and ten age-matched able-bodied participants were provided with real-time visual feedback of the position of their CoP while standing on a pressure platform. Their task was to keep their CoP within a small circle in the center of a computer screen placed at eye level, which could be achieved by minimizing their postural sway. The visual feedback was then delayed by 250 and 500 ms and was combined with a two- and five-fold amplification of the CoP displacements. Trials with eyes open without augmented visual feedback as well as with eyes closed were further performed. The overall performance was measured by computing the sway area. We further quantified the dynamics of the CoP adjustments using the entropic half-life (EnHL) to study possible physiological mechanisms behind postural control. Amputees showed an increased sway area compared to the control group. The EnHL values of the amputated leg were significantly higher than those of the intact leg and the dominant and non-dominant leg of controls. This indicates lower dynamics in the CoP adjustments of the amputated leg, which was compensated by increasing the dynamics of the CoP adjustments of the intact leg. Receiving real-time visual feedback of the CoP position did not significantly reduce the sway area neither in amputees nor in controls when comparing with the eyes open condition without visual feedback of the CoP position. Further, with increasing delay and amplification, both groups were able to compensate for small visual perturbations, yet their dynamics were significantly lower when additional information was not received in a physiologically relevant time frame. These findings may be used for future design of neurorehabilitation programs to restore sensory feedback in lower limb amputees.

5.
J Hepatol ; 75(3): 634-646, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33872692

RESUMO

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC) is characterized by chronic inflammation and progressive fibrosis of the biliary tree. The bile acid receptor TGR5 (GPBAR1) is found on biliary epithelial cells (BECs), where it promotes secretion, proliferation and tight junction integrity. Thus, we speculated that changes in TGR5-expression in BECs may contribute to PSC pathogenesis. METHODS: TGR5-expression and -localization were analyzed in PSC livers and liver tissue, isolated bile ducts and BECs from Abcb4-/-, Abcb4-/-/Tgr5Tg and ursodeoxycholic acid (UDCA)- or 24-norursodeoxycholic acid (norUDCA)-fed Abcb4-/- mice. The effects of IL8/IL8 homologues on TGR5 mRNA and protein levels were studied. BEC gene expression was analyzed by single-cell transcriptomics (scRNA-seq) from distinct mouse models. RESULTS: TGR5 mRNA expression and immunofluorescence staining intensity were reduced in BECs of PSC and Abcb4-/- livers, in Abcb4-/- extrahepatic bile ducts, but not in intrahepatic macrophages. No changes in TGR5 BEC fluorescence intensity were detected in liver tissue of other liver diseases, including primary biliary cholangitis. Incubation of BECs with IL8/IL8 homologues, but not with other cytokines, reduced TGR5 mRNA and protein levels. BECs from Abcb4-/- mice had lower levels of phosphorylated Erk and higher expression levels of Icam1, Vcam1 and Tgfß2. Overexpression of Tgr5 abolished the activated inflammatory phenotype characteristic of Abcb4-/- BECs. NorUDCA-feeding restored TGR5-expression levels in BECs in Abcb4-/- livers. CONCLUSIONS: Reduced TGR5 levels in BECs from patients with PSC and Abcb4-/- mice promote development of a reactive BEC phenotype, aggravate biliary injury and thus contribute to the pathogenesis of sclerosing cholangitis. Restoration of biliary TGR5-expression levels represents a previously unknown mechanism of action of norUDCA. LAY SUMMARY: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease-associated with progressive inflammation of the bile duct, leading to fibrosis and end-stage liver disease. Bile acid (BA) toxicity may contribute to the development and disease progression of PSC. TGR5 is a membrane-bound receptor for BAs, which is found on bile ducts and protects bile ducts from BA toxicity. In this study, we show that TGR5 levels were reduced in bile ducts from PSC livers and in bile ducts from a genetic mouse model of PSC. Our investigations indicate that lower levels of TGR5 in bile ducts may contribute to PSC development and progression. Furthermore, treatment with norUDCA, a drug currently being tested in a phase III trial for PSC, restored TGR5 levels in biliary epithelial cells.


Assuntos
Sistema Biliar/efeitos dos fármacos , Colangite Esclerosante/genética , Regulação para Baixo/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Animais , Sistema Biliar/metabolismo , Colangite Esclerosante/tratamento farmacológico , Colangite Esclerosante/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Virulência
6.
Sci Rep ; 11(1): 2901, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536452

RESUMO

Pancreatic cystic lesions (PCL) are increasingly diagnosed. Endoscopic ultrasound fine-needle aspiration (EUS-FNA) cytology is often used for diagnostic confirmation but can be inconclusive. In this study, the role of molecular analyses in the pre-operative diagnostics of PCL is evaluated. Targeted Next Generation Sequencing (NGS) applied on cytology smears was retrospectively evaluated in a cohort of 37 resected PCL. Usefulness of NGS on fresh cyst fluids was tested in a prospective cohort of patients with newly diagnosed PCL (n = 71). In the retrospective cohort, cytology plus NGS displayed higher sensitivity (94.1% vs. 87.1%) and specificity (100% vs. 50%) than cytology alone for the detection of mucinous neoplasms. In the prospective cohort, sensitivity and specificity of conventional cytology alone were 54.2% and 100% for the detection of mucinous neoplasia and 50.0% and 100% for the detection of high-grade dysplasia, respectively. Adding NGS, all lesions which underwent histopathologic verification (12/71, 17%) could be classified without false positive or false negative results regarding the detection of mucinous neoplasm so far. NGS analysis of cfDNA in PCL fluids is feasible and can increase diagnostic accuracy in the detection of mucinous neoplasms compared to cytology alone. However, algorithms for the detection of high-risk lesions need further improvement.


Assuntos
DNA Tumoral Circulante/análise , Líquido Cístico/química , Cisto Pancreático/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Tumoral Circulante/genética , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Estudos de Viabilidade , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pâncreas/cirurgia , Cisto Pancreático/etiologia , Cisto Pancreático/genética , Cisto Pancreático/cirurgia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Período Pré-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
7.
Commun Biol ; 4(1): 113, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495542

RESUMO

The Wartberg culture (WBC, 3500-2800 BCE) dates to the Late Neolithic period, a time of important demographic and cultural transformations in western Europe. We performed genome-wide analyses of 42 individuals who were interred in a WBC collective burial in Niedertiefenbach, Germany (3300-3200 cal. BCE). The results showed that the farming population of Niedertiefenbach carried a surprisingly large hunter-gatherer ancestry component (34-58%). This component was most likely introduced during the cultural transformation that led to the WBC. In addition, the Niedertiefenbach individuals exhibited a distinct human leukocyte antigen gene pool, possibly reflecting an immune response that was geared towards detecting viral infections.


Assuntos
Agricultura , Comportamento Alimentar/fisiologia , Antígenos HLA/genética , Comportamento Predatório/fisiologia , Animais , Arqueologia , DNA Antigo/análise , Europa (Continente) , Evolução Molecular , Variação Genética , Genética Populacional , Genoma Humano , Estudo de Associação Genômica Ampla , Alemanha , História Antiga , Migração Humana , Humanos , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genética , Características de Residência
8.
Int J Paleopathol ; 32: 61-73, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33360164

RESUMO

OBJECTIVE: This study discusses the challenges and possibilities of establishing a definition for Ancient Rare Diseases (ARD) in a probable case of Legg-Calvé-Perthes Disease (LCPD) from the Bronze Age cemetery Kudachurt 14, situated in the Northern Caucasus. MATERIALS: We investigated the skeletal remains of a male aged 35-45 years at death. For comparison we examined other males buried at Kudachurt 14 (n = 24) and reviewed 22 LCPD cases from the paleopathological literature. METHODS: We use macroscopic as well as osteometric examination methods and imaging techniques. RESULTS: The morphology of the left hip joint corresponds to skeletal characteristics for LCPD. Co-occurring osteochondrosis dissecans, femoral anteversion, and atrophy of the left femoral shaft suggest a complex disease course. CONCLUSIONS: Modern criteria of rare diseases applied on ancient skeletal remains are either non-transferable or require completion. We conclude that rarity is dynamic, etiological uncertainty has to be accepted, and the respective socioeconomic context is crucial. Degree of disability and level of sociomedical investment are not defining criteria for ARD. SIGNIFICANCE: Dating 2200-1650 cal BCE, this study currently presents the earliest case of probable LCPD. This is the first attempt to transform modern characteristics of rare diseases for establishing a paleopathological concept of ARD. LIMITATIONS: As this study is limited to LCPD, our conclusions are not directly applicable to other ARD in question. SUGGESTIONS FOR FURTHER RESEARCH: More focused paleopathological research on skeletal populations from different cultures and time periods is needed, enabling an evolutionary perspective on the comparability of ancient, modern and future rare diseases.


Assuntos
Doença de Legg-Calve-Perthes , Osteocondrite Dissecante , Articulação do Quadril , Humanos , Masculino , Paleopatologia , Doenças Raras
9.
Cancers (Basel) ; 13(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375555

RESUMO

Currently available serum biomarkers for pancreatobiliary cancers lack sensitivity and specificity and ultimate diagnosis still requires invasive procedures for histological confirmation. The detection of tumor-specific genetic aberrations with utilization of cell free DNA (cfDNA) is a less invasive approach than traditional tissue biopsies; however, it has not been implemented into clinical routine. In this study, we investigated bile as a liquid biopsy source in pancreatobiliary cancers and compared its potential as cell-free DNA source to plasma. Blood (n = 37) and bile (n = 21) samples were collected from patients affected by pancreatic ductal adenocarcinoma (PDAC) and extrahepatic cholangiocarcinoma (CCA) or with non-malignant biliary obstructions (blood n = 16; bile n = 21). Panel-based next generation sequencing (NGS) and digital droplet PCR (ddPCR) were applied for tumor mutation profiling. NGS results from matched tumor tissues (n = 29) served as comparison. Sequencing of cfDNA from bile resulted in detection of 96.2% of the pathogenic tumor mutations found in matched tissue samples. On the other hand, only 31.6% of pathogenic tumor mutations found in tissue could be detected in plasma. In a direct comparison, only half of the mutations detected in bile cfDNA were concordantly detected in plasma from the same patients. Panel NGS and ddPCR displayed comparable sensitivity. In conclusion, bile is a suitable source of cfDNA for the diagnosis of pancreatobiliary cancer and performs more reliably than plasma. Although primary diagnosis still requires histologic confirmation, bile-derived cfDNA could offer an alternative if tissue sampling is not feasible and might allow less invasive disease monitoring.

10.
Nat Commun ; 10(1): 590, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30713341

RESUMO

Archaeogenetic studies have described the formation of Eurasian 'steppe ancestry' as a mixture of Eastern and Caucasus hunter-gatherers. However, it remains unclear when and where this ancestry arose and whether it was related to a horizon of cultural innovations in the 4th millennium BCE that subsequently facilitated the advance of pastoral societies in Eurasia. Here we generated genome-wide SNP data from 45 prehistoric individuals along a 3000-year temporal transect in the North Caucasus. We observe a genetic separation between the groups of the Caucasus and those of the adjacent steppe. The northern Caucasus groups are genetically similar to contemporaneous populations south of it, suggesting human movement across the mountain range during the Bronze Age. The steppe groups from Yamnaya and subsequent pastoralist cultures show evidence for previously undetected farmer-related ancestry from different contact zones, while Steppe Maykop individuals harbour additional Upper Palaeolithic Siberian and Native American related ancestry.

11.
EMBO Rep ; 19(12)2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30337494

RESUMO

Chitin is the second most abundant polysaccharide in nature and linked to fungal infection and asthma. However, bona fide immune receptors directly binding chitin and signaling immune activation and inflammation have not been clearly identified because polymeric crude chitin with unknown purity and molecular composition has been used. By using defined chitin (N-acetyl-glucosamine) oligomers, we here identify six-subunit-long chitin chains as the smallest immunologically active motif and the innate immune receptor Toll-like receptor (TLR2) as a primary fungal chitin sensor on human and murine immune cells. Chitin oligomers directly bind TLR2 with nanomolar affinity, and this fungal TLR2 ligand shows overlapping and distinct signaling outcomes compared to known mycobacterial TLR2 ligands. Unexpectedly, chitin oligomers composed of five or less subunits are inactive, hinting to a size-dependent system of immuno-modulation that appears conserved in plants and humans. Since blocking of the chitin-TLR2 interaction effectively prevents chitin-mediated inflammation in vitro and in vivo, our study highlights the chitin-TLR2 interaction as a potential target for developing novel therapies in chitin-related pathologies and fungal disease.


Assuntos
Quitina/química , Quitina/metabolismo , Fungos/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Receptor 2 Toll-Like/metabolismo , Animais , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Quitinases/metabolismo , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Fatores Imunológicos/farmacologia , Ligantes , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células THP-1 , Receptor 1 Toll-Like/agonistas , Receptor 1 Toll-Like/metabolismo , Receptor 2 Toll-Like/química , Zimosan/metabolismo
12.
Int J Clin Pract ; 72(12): e13272, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30329199

RESUMO

OBJECTIVE: The aim of this multi-centre, randomised, double-blind, placebo-controlled trial was to compare the efficacy and safety of the fixed combination of 0.5 mg tyrothricin, 1.0 mg benzalkonium chloride, and 1.5 mg benzocaine (study drug marketed as Dorithricin® ) in repeat dosing for 3 days to match placebo lozenges in the treatment of acute pharyngitis in adults. METHODS: Patients (pts, aged ≥18 years) with acute pharyngitis, ie, non-streptococcal sore throat and moderate-to-severe pain (intensity NRS ≥ 7; VAS ≥ 50) were assigned to study drug (n = 160) or matching placebo (n = 161). Efficacy was assessed by investigator for 2 hours post initial dose (p.i.d.), and 3 days later (Visit 2). Primary efficacy endpoint was the complete resolution of throat pain and difficulty in swallowing at Visit 2 (3 days p.i.d.). Safety and local tolerability were also assessed. RESULTS: Seventy-two hours (p.i.d.), complete resolution of throat pain and difficulty in swallowing were achieved by 44.6% patients on study drug compared with 27.2% patients on placebo (difference 17.4% (CI [5.8%; 29.7%]; 64% improvement [GEE, P = 0.0022]). Until 2 hours p.i.d., reduction in symptoms was better with study drug (P < 0.005). Treatment satisfaction was higher with study drug (patients'/investigators' assessment (78.9%/78.9% vs 55.0%/55.6% for placebo) and was well tolerated, overall safety profile was comparable to placebo. CONCLUSION: The strength of this randomised controlled trial lies in the endpoint of complete remission after 3 days p.i.d., especially in the light of other trials addressing acute pharyngitis. The results of this study show a significant benefit of the study drug over placebo in the treatment of acute pharyngitis. Local treatment with the fixed combination (0.5 mg tyrothricin, 1.0 mg benzalkonium chloride, and 1.5 mg benzocaine) provides a rapid analgesic effect and is effective in relieving both severe throat pain as well as difficulty in swallowing associated with acute pharyngitis leading to a 64% improved complete remission within 72 hours. The triple active combination is a suitable treatment option for patients in the self-management of acute pharyngitis and sore throat. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT03323528.


Assuntos
Compostos de Benzalcônio/uso terapêutico , Benzocaína/uso terapêutico , Dor/tratamento farmacológico , Faringite/tratamento farmacológico , Tirotricina/uso terapêutico , Doença Aguda , Administração Oral , Adulto , Deglutição , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Satisfação do Paciente , Faringite/complicações , Resultado do Tratamento , Adulto Jovem
13.
Immunol Lett ; 202: 31-37, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30076856

RESUMO

Myeloid-derived suppressor cells (MDSC) represent an innate immune cell subset capable of suppressing T-cell responses in cancer and chronic inflammation. While the effect of MDSC on T cells has been defined thoroughly, the reciprocal impact of T cells on MDSC homeostasis remains poorly understood. Therefore, we comprehensively analyzed the effect of different T-cell subsets on the generation and survival of human MDSC. Using an in vitro MDSC generation assay, we demonstrate that unstimulated CD4+, but not CD8+ T cells, induce polymorphonuclear MDSC (PMN-MDSC) from CD33+ myeloid cells. This effect was dependent on direct cell-cell contact and required TNF-α signaling. Soluble TNF-α was dispensable for PMN-MDSC generation, suggesting that transmembrane TNF-α is involved in that trans-cellular process. Stimulated human CD3+ T cells delayed the apoptosis of PMN-MDSC, which was independent of TNF-α signaling or direct cell-cell contact, but was recapitulated by IL-2. Taken together, our study shows that human T cells modulate MDSC generation and survival through two distinct mechanisms and thereby fine-tune the homeostasis of human MDSC in a regulated manner.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Mieloides/imunologia , Células Supressoras Mieloides/imunologia , Fator de Necrose Tumoral alfa/imunologia , Apoptose/imunologia , Células Cultivadas , Homeostase/imunologia , Humanos , Interleucina-2/imunologia , Neoplasias/imunologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Transdução de Sinais/imunologia
14.
J Biol Chem ; 293(8): 2829-2840, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29301933

RESUMO

The heterodimeric human (h) electron-transferring flavoprotein (ETF) transfers electrons from at least 13 different flavin dehydrogenases to the mitochondrial respiratory chain through a non-covalently bound FAD cofactor. Here, we describe the discovery of an irreversible and pH-dependent oxidation of the 8α-methyl group to 8-formyl-FAD (8f-FAD), which represents a unique chemical modification of a flavin cofactor in the human flavoproteome. Furthermore, a set of hETF variants revealed that several conserved amino acid residues in the FAD-binding pocket of electron-transferring flavoproteins are required for the conversion to the formyl group. Two of the variants generated in our study, namely αR249C and αT266M, cause glutaric aciduria type II, a severe inherited disease. Both of the variants showed impaired formation of 8f-FAD shedding new light on the potential molecular cause of disease development. Interestingly, the conversion of FAD to 8f-FAD yields a very stable flavin semiquinone that exhibited slightly lower rates of electron transfer in an artificial assay system than hETF containing FAD. In contrast, the formation of 8f-FAD enhanced the affinity to human dimethylglycine dehydrogenase 5-fold, indicating that formation of 8f-FAD modulates the interaction of hETF with client enzymes in the mitochondrial matrix. Thus, we hypothesize that the FAD cofactor bound to hETF is subject to oxidation in the alkaline (pH 8) environment of the mitochondrial matrix, which may modulate electron transport between client dehydrogenases and the respiratory chain. This discovery challenges the current concepts of electron transfer processes in mitochondria.


Assuntos
Flavoproteínas Transferidoras de Elétrons/metabolismo , Flavina-Adenina Dinucleotídeo/análogos & derivados , Flavina-Adenina Dinucleotídeo/metabolismo , Modelos Moleculares , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Biocatálise , Domínio Catalítico , Sequência Conservada , Transporte de Elétrons , Flavoproteínas Transferidoras de Elétrons/química , Flavoproteínas Transferidoras de Elétrons/genética , Flavina-Adenina Dinucleotídeo/química , Humanos , Concentração de Íons de Hidrogênio , Deficiência Múltipla de Acil Coenzima A Desidrogenase/enzimologia , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Mutagênese Sítio-Dirigida , Mutação , Oxirredução , Engenharia de Proteínas , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
15.
Cell Adh Migr ; 11(5-6): 476-487, 2017 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-27874296

RESUMO

The attachment of cancer cells to the endothelium is an essential step during metastatic dissemination. The cell surface receptor CD44 is capable of binding to hyaluronan (HA) produced by tumor cells and by cells of the tumor microenvironment, including blood endothelial cells. Here, we investigated the role of CD44 in the interaction between the liver cancer cell line HepG2Iso and HA surfaces. The rolling interaction was quantitatively analyzed using a microfluidic shear force setup. It was found that rolling of the liver cancer cells on HA depends on CD44, which mediates a catch-bond interaction and thus a flow-induced rolling of the cells. Reduction of CD44 expression by means of siRNA, inhibition of the interaction of CD44 with HA by antibody blocking, and treatment with low molecular weight HA inhibited liver cancer cell rolling on HA-coated surfaces. The results not only clearly show the dependency of the shear-induced catch-bond interaction of HepG2Iso cells on CD44 and HA, but also for the first time demonstrate CD44-mediated rolling for epithelium-derived cells that are typically adherent.


Assuntos
Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Adesão Celular , Movimento Celular , Células Hep G2 , Humanos , Resistência ao Cisalhamento
16.
Mol Cell Pediatr ; 2(1): 3, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26542293

RESUMO

Chitin, after cellulose, the second most abundant biopolymer on earth, is a key component of insects, fungi, and house-dust mites. Lower life forms are endowed with chitinases to defend themselves against chitin-bearing pathogens. Unexpectedly, humans were also found to express chitinases as well as chitinase-like proteins that modulate immune responses. Particularly, increased levels of the chitinase-like protein YKL-40 have been associated with severe asthma, cystic fibrosis, and other inflammatory disease conditions. Here, we summarize and discuss the potential role of chitin, chitinases, and chitinase-like proteins in pediatric lung diseases.

17.
J Child Sex Abus ; 24(7): 796-815, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26523447

RESUMO

The aim of this research is to study the improvement of empathy in child-care professionals (i.e., teachers, psychologists, social workers) involved in the prevention of sexual abuse against children and youngsters. An E-Learning training pilot program was conducted with pre- and post-measures (T(1) = at the beginning and T(2) = after 6 months) using the program's standardized questionnaires of Situational Empathy and the Interpersonal Reactivity Index (IRI) as a Dispositional Empathy measure. A sample of 42 experienced professionals involved in activities with children and youngsters was obtained from the International Movement of Popular Education in Latin America called "Fe y Alegría." Significant progress was found in the scales of Situational Empathy and in some Coping subscales. The final outcomes seem to indicate that the prevention program elicits important changes in the cognitive sphere and that these changes are more intense when the implication level for the situation is greater. This research shows that empathy can be improved through professional experience and careful situational involvement.


Assuntos
Abuso Sexual na Infância/prevenção & controle , Educação Profissionalizante/métodos , Empatia , Docentes , Pessoal de Saúde/psicologia , Relações Interpessoais , Adolescente , Adulto , Idoso , Criança , Feminino , Pessoal de Saúde/educação , Humanos , Masculino , Pessoa de Meia-Idade , Competência Profissional , Adulto Jovem
18.
PLoS One ; 9(4): e94654, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24728341

RESUMO

PURPOSE: Design, validation and application of an accelerated fast spin-echo (FSE) variant that uses a split-echo approach for self-calibrated parallel imaging. METHODS: For self-calibrated, split-echo FSE (SCSE-FSE), extra displacement gradients were incorporated into FSE to decompose odd and even echo groups which were independently phase encoded to derive coil sensitivity maps, and to generate undersampled data (reduction factor up to R = 3). Reference and undersampled data were acquired simultaneously. SENSE reconstruction was employed. RESULTS: The feasibility of SCSE-FSE was demonstrated in phantom studies. Point spread function performance of SCSE-FSE was found to be competitive with traditional FSE variants. The immunity of SCSE-FSE for motion induced mis-registration between reference and undersampled data was shown using a dynamic left ventricular model and cardiac imaging. The applicability of black blood prepared SCSE-FSE for cardiac imaging was demonstrated in healthy volunteers including accelerated multi-slice per breath-hold imaging and accelerated high spatial resolution imaging. CONCLUSION: SCSE-FSE obviates the need of external reference scans for SENSE reconstructed parallel imaging with FSE. SCSE-FSE reduces the risk for mis-registration between reference scans and accelerated acquisitions. SCSE-FSE is feasible for imaging of the heart and of large cardiac vessels but also meets the needs of brain, abdominal and liver imaging.


Assuntos
Imagem Ecoplanar/métodos , Coração/diagnóstico por imagem , Calibragem , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Radiografia
19.
Artigo em Inglês | MEDLINE | ID: mdl-24517625

RESUMO

Sexual abuse can lead to long-lasting, even life-long, consequences and is a serious problem on an individual, familial and societal level. Therefore, prevention measures on different levels are a public health issue. Minors as well as adults should be involved in prevention work in order to prevent sexual abuse of minors in a sustainable way. Besides norms, structures and values in society, the respective laws as well as attitudes and structures should be changed and amended in such a way that abusers and the abuse are clearly confronted everywhere. In the last decades, numerous prevention programs for victims have been developed for various target groups (e.g. parenting education classes, home-visiting programs, public education, training sessions for teachers, E-Learning Programs of the German Federal Ministry for Education and Research and the Centre for Child Protection). Many of these programs have proven partially effective. Nevertheless, until now there is no consensus in the scientific community on what constitutes effectiveness in this context. Reasons for this are the discrepancies in definitions or the scarcity of attention which the evaluation of prevention measures has received.

20.
Magn Reson Med ; 72(6): 1590-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24347265

RESUMO

PURPOSE: This work proposes a dual contrast rapid acquisition with relaxation enhancement (RARE) variant (2in1-RARE), which provides simultaneous proton density (PD) and T2 * contrast in a single acquisition. THEORY AND METHODS: The underlying concept of 2in1-RARE is the strict separation of spin echoes and stimulated echoes. This approach offers independent weighting of spin echoes and stimulated echoes. 2in1-RARE was evaluated in phantoms including signal-to-noise ratio (SNR) and point spread function assessment. 2in1-RARE was benchmarked versus coherent RARE and a split-echo RARE variant. The applicability of 2in1-RARE for brain imaging was demonstrated in a small cohort of healthy subjects (n = 10) and, exemplary, a multiple sclerosis patient at 3 Tesla as a precursor to a broader clinical study. RESULTS: 2in1-RARE enables the simultaneous acquisition of dual contrast weighted images without any significant image degradation and without sacrificing SNR versus split-echo RARE. This translates into a factor of two speed gain over multi-contrast, sequential split-echo RARE. A 15% broadening of the point spread function was observed in 2in1-RARE. T1 relaxation effects during the mixing time can be neglected for brain tissue. CONCLUSION: 2in1-RARE offers simultaneous acquisition of images of anatomical (PD) and functional (T2 *) contrast. It presents an alternative to address scan time constraints frequently encountered during sequential acquisition of T2 * or PD-weighted RARE.


Assuntos
Algoritmos , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Esclerose Múltipla/patologia , Adulto , Imagem de Difusão por Ressonância Magnética/instrumentação , Feminino , Humanos , Masculino , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
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