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1.
PLoS One ; 14(5): e0215214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31042741

RESUMO

We analyze the processing of cereals and its role at Early Neolithic Göbekli Tepe, southeastern Anatolia (10th / 9th millennium BC), a site that has aroused much debate in archaeological discourse. To date, only zooarchaeological evidence has been discussed in regard to the subsistence of its builders. Göbekli Tepe consists of monumental round to oval buildings, erected in an earlier phase, and smaller rectangular buildings, built around them in a partially contemporaneous and later phase. The monumental buildings are best known as they were in the focus of research. They are around 20 m in diameter and have stone pillars that are up to 5.5 m high and often richly decorated. The rectangular buildings are smaller and-in some cases-have up to 2 m high, mostly undecorated, pillars. Especially striking is the number of tools related to food processing, including grinding slabs/bowls, handstones, pestles, and mortars, which have not been studied before. We analyzed more than 7000 artifacts for the present contribution. The high frequency of artifacts is unusual for contemporary sites in the region. Using an integrated approach of formal, experimental, and macro- / microscopical use-wear analyses we show that Neolithic people at Göbekli Tepe have produced standardized and efficient grinding tools, most of which have been used for the processing of cereals. Additional phytolith analysis confirms the massive presence of cereals at the site, filling the gap left by the weakly preserved charred macro-rests. The organization of work and food supply has always been a central question of research into Göbekli Tepe, as the construction and maintenance of the monumental architecture would have necessitated a considerable work force. Contextual analyses of the distribution of the elements of the grinding kit on site highlight a clear link between plant food preparation and the rectangular buildings and indicate clear delimitations of working areas for food production on the terraces the structures lie on, surrounding the circular buildings. There is evidence for extensive plant food processing and archaeozoological data hint at large-scale hunting of gazelle between midsummer and autumn. As no large storage facilities have been identified, we argue for a production of food for immediate use and interpret these seasonal peaks in activity at the site as evidence for the organization of large work feasts.


Assuntos
Agricultura/história , Grão Comestível , Manipulação de Alimentos/instrumentação , Agricultura/instrumentação , Arqueologia , Manipulação de Alimentos/história , História Antiga , Humanos , Turquia
2.
Pharmaceuticals (Basel) ; 11(2)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29849009

RESUMO

Maintenance of body weight is fundamental to maintain one's health and to promote longevity. Nevertheless, it appears that the global obesity epidemic is still constantly increasing. Endocannabinoids (eCBs) are lipid messengers that are involved in overall body weight control by interfering with manifold central and peripheral regulatory circuits that orchestrate energy homeostasis. Initially, blocking of eCB signaling by first generation cannabinoid type 1 receptor (CB1) inverse agonists such as rimonabant revealed body weight-reducing effects in laboratory animals and men. Unfortunately, rimonabant also induced severe psychiatric side effects. At this point, it became clear that future cannabinoid research has to decipher more precisely the underlying central and peripheral mechanisms behind eCB-driven control of feeding behavior and whole body energy metabolism. Here, we will summarize the most recent advances in understanding how central eCBs interfere with circuits in the brain that control food intake and energy expenditure. Next, we will focus on how peripheral eCBs affect food digestion, nutrient transformation and energy expenditure by interfering with signaling cascades in the gastrointestinal tract, liver, pancreas, fat depots and endocrine glands. To finally outline the safe future potential of cannabinoids as medicines, our overall goal is to address the molecular, cellular and pharmacological logic behind central and peripheral eCB-mediated body weight control, and to figure out how these precise mechanistic insights are currently transferred into the development of next generation cannabinoid medicines displaying clearly improved safety profiles, such as significantly reduced side effects.

3.
J Med Chem ; 60(21): 8982-8988, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29028171

RESUMO

Macrocyclic peptides can interfere with challenging biomolecular targets including protein-protein interactions. Whereas there are various approaches that facilitate the identification of peptide-derived ligands, their evolution into higher affinity binders remains a major hurdle. We report a virtual screen based on molecular docking that allows the affinity maturation of macrocyclic peptides taking non-natural amino acids into consideration. These macrocycles bear large and flexible substituents that usually complicate the use of docking approaches. A virtual library containing more than 1400 structures was screened against the target focusing on docking poses with the core structure resembling a known bioactive conformation. Based on this screen, a macrocyclic peptide 22 involving two non-natural amino acids was evolved showing increased target affinity and biological activity. Predicted binding modes were verified by X-ray crystallography. The presented workflow allows the screening of large macrocyclic peptides with diverse modifications thereby expanding the accessible chemical space and reducing synthetic efforts.


Assuntos
Desenho de Fármacos , Peptídeos Cíclicos/farmacologia , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Aminoácidos , Animais , Sítios de Ligação , Cristalografia por Raios X , Humanos , Simulação de Acoplamento Molecular , Biblioteca de Peptídeos , Peptídeos Cíclicos/química , Ligação Proteica/efeitos dos fármacos , Relação Estrutura-Atividade
4.
Cell Chem Biol ; 24(8): 958-968.e5, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28757184

RESUMO

The Wnt signaling pathway plays a critical role in cell proliferation and differentiation, thus it is often associated with diseases such as cancers. Unfortunately, although attractive, developing anti-cancer strategy targeting Wnt signaling has been challenging given that the most attractive targets are involved in protein-protein interactions (PPIs). Here, we develop a stapled peptide inhibitor that targets the interaction between ß-catenin and T cell factor/lymphoid enhancer-binding factor transcription factors, which are crucially involved in Wnt signaling. Our integrative approach combines peptide stapling to optimize proteolytic stability, with lessons learned from cell-penetrating peptide (CPP) design to maximize cellular uptake resulting in NLS-StAx-h, a selective, cell permeable, stapled peptide inhibitor of oncogenic Wnt signaling that efficiently inhibits ß-catenin-transcription factor interactions. We expect that this type of integrative strategy that endows stapled peptides with CPP features will be generally useful for developing inhibitors of intracellular PPIs.


Assuntos
Peptídeos Penetradores de Células/metabolismo , beta Catenina/metabolismo , Sequência de Aminoácidos , Proteína Axina/genética , Proteína Axina/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Células HeLa , Humanos , Microscopia Confocal , Domínios e Motivos de Interação entre Proteínas , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores
5.
ACS Chem Biol ; 11(8): 2375-82, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27336832

RESUMO

Small GTPases comprise a family of highly relevant targets in chemical biology and medicinal chemistry research and have been considered "undruggable" due to the persisting lack of effective synthetic modulators and suitable binding pockets. As molecular switches, small GTPases control a multitude of pivotal cellular functions, and their dysregulation is associated with many human diseases such as various forms of cancer. Rab-GTPases represent the largest subfamily of small GTPases and are master regulators of vesicular transport interacting with various proteins via flat and extensive protein-protein interactions (PPIs). The only reported synthetic inhibitor of a PPI involving an activated Rab GTPase is the hydrocarbon stapled peptide StRIP3. However, this macrocyclic peptide shows low proteolytic stability and cell permeability. Here, we report the design of a bioavailable StRIP3 analogue that harbors two hydrophobic cross-links and exhibits increased binding affinity, combined with robust cellular uptake and extremely high proteolytic stability. Localization experiments reveal that this double-stapled peptide and its target protein Rab8a accumulate in the same cellular compartments. The reported approach offers a strategy for the implementation of biostability into conformationally constrained peptides while supporting cellular uptake and target affinity, thereby conveying drug-like properties.


Assuntos
Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Sequência de Aminoácidos , Disponibilidade Biológica , Células HeLa , Humanos , Peptídeos/química , Permeabilidade
6.
J Psychosoc Oncol ; 33(1): 1-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25396697

RESUMO

Distress is common in patients with gastrointestinal cancers. Most conventional scales are too long for routine clinic use. We tested the Emotion Thermometers (ET) tool, a brief visual-analogue scale. There are four emotional upset thermometers: distress, anxiety, depression, and anger. Sixty-nine surgical patients were recruited from an academic hospital clinic in 2012; 64 had complete data for Beck depression inventory and ET. The sample size was modest due to the specialist nature of the sample. We examined sensitivity, specificity, and area under the receiver-operator-curve. A dimensional multi-domain approach to screening for emotional disorders is preferable to using the distress thermometer alone and can be achieved with little extra time burden to clinicians. The ET is a diagnostic tool that is primarily designed for screening to identify cancer patients who would benefit by enhanced psychosocial care.


Assuntos
Ira , Ansiedade/diagnóstico , Depressão/diagnóstico , Neoplasias Gastrointestinais/psicologia , Programas de Rastreamento/instrumentação , Escalas de Graduação Psiquiátrica , Estresse Psicológico/diagnóstico , Neoplasias Gastrointestinais/cirurgia , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade
7.
J Biotechnol ; 167(3): 287-95, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-23871655

RESUMO

T7 RNA polymerase is an important biocatalyst that is used in diverse biotechnological applications such as in vitro transcription or protein expression. The enzyme displays high substrate specificity which is payed by significant limitations regarding incorporation of synthetic nucleotide analogs. Of specific interest is enzymatic synthesis of 2'-O-methyl-modified RNA as these nucleic acids exhibit improved biochemical and pharmacokinetic properties that make them attractive for diagnostic and therapeutic purposes. We report here on the development of an activity-based selection/screening approach for assessing polymerase activities in the presence of 2'-O-methyl-modified nucleotides, and on the identification of one variant T7 RNA polymerase which is capable of synthesizing all-2'-O-methyl RNA.


Assuntos
RNA Polimerases Dirigidas por DNA/química , Nucleosídeos/química , RNA Bacteriano/química , Proteínas Virais/química , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Biotecnologia , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Escherichia coli/genética , Humanos , Mutagênese Sítio-Dirigida , Mutação , Nucleosídeos/metabolismo , Plasmídeos , RNA Bacteriano/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
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