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1.
Artículo en Inglés | MEDLINE | ID: mdl-37052767

RESUMEN

BACKGROUND: The colonization of skin with pathogenic, partially antibiotic-resistant bacteria is frequently a severe problem in dermatological therapies. For instance, skin colonization with Staphylococcus aureus is even a disease-promoting factor in atopic dermatitis. The photodynamic inactivation (PDI) of bacteria could be a new antibacterial procedure. Upon irradiation with visible light, a special photosensitizer exclusively generates singlet oxygen. This reactive oxygen species kills bacteria via oxidation independent of species or strain and their antibiotic resistance profile causing no bacterial resistance on its part. OBJECTIVE: To investigate the antibacterial potential of a photosensitizer, formulated in a new hydrogel, on human skin ex vivo. METHODS: The photochemical stability of the photosensitizer and its ability to generate singlet oxygen in the hydrogel was studied. Antimicrobial efficacy of this hydrogel was tested step by step, firstly on inanimate surfaces and then on human skin ex vivo against S. aureus and Pseudomonas aeruginosa using standard colony counting. NBTC staining and TUNEL assays were performed on skin biopsies to investigate potential necrosis and apoptosis effects in skin cells possibly caused by PDI. RESULTS: None of the hydrogel components affected the photochemical stability and the life time of singlet oxygen. On inanimate surfaces as well as on the human skin, the number of viable bacteria was reduced by up to 4.8 log10 being more effective than most other antibacterial topical agents. Histology and assays showed that PDI against bacteria on the skin surface caused no harmful effects on the underlying skin cells. CONCLUSION: Photodynamic inactivation hydrogel proved to be effective for decolonization of human skin including the potential to act against superficial skin infections. Being a water-based formulation, the hydrogel should be also suitable for the mucosa. The results of the present ex vivo study form a good basis for conducting clinical studies in vivo.

2.
Mol Cell ; 48(1): 63-74, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-22921937

RESUMEN

How nascent polypeptides emerging from ribosomes fold into functional structures is poorly understood. Here, we monitor disulfide bond formation, protease resistance, and enzymatic activity in nascent polypeptides to show that in close proximity to the ribosome, conformational space and kinetics of folding are restricted. Folding constraints decrease incrementally with distance from the ribosome surface. Upon ribosome binding, the chaperone Trigger Factor counters folding also of longer nascent chains, to extents varying between different chain segments. Trigger Factor even binds and unfolds pre-existing folded structures, the unfolding activity being limited by the thermodynamic stability of nascent chains. Folding retardation and unfolding activities are not shared by the DnaK chaperone assisting later folding steps. These ribosome- and Trigger Factor-specific activities together constitute an efficient mechanism to prevent or even revert premature folding, effectively limiting misfolded intermediates during protein synthesis.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Pliegue de Proteína , Ribosomas/metabolismo , Proteínas Bacterianas , Disulfuros/metabolismo , Proteínas de Escherichia coli/química , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/metabolismo , Modelos Biológicos , Modelos Moleculares , Chaperonas Moleculares/química , Chaperonas Moleculares/metabolismo , Isomerasa de Peptidilprolil/química , Conformación Proteica , Estructura Terciaria de Proteína , Ribonucleasas/química , Ribonucleasas/metabolismo , Tetrahidrofolato Deshidrogenasa/química , Tetrahidrofolato Deshidrogenasa/metabolismo
3.
Drug Dev Ind Pharm ; 46(11): 1753-1762, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33006298

RESUMEN

OBJECTIVE: Probiotic bacteria, such as different lactobacilli strains, have successfully been used to treat gingivitis and periodontitis or caries. By formulating probiotics as orodispersible tablet (ODT), the benefits of this dosage form could be utilized. Without any further measures, the probiotic bacteria will be eliminated too fast from the intended site of action, the oral mucosa. The use of mucoadhesive granules, composed of mucoadhesive polymer and probiotics, is a promising strategy to prolong the contact time between lactobacilli and oral mucosa without delaying disintegration. METHODS: Three common mucoadhesive polymers, anionic Carbopol 971P NF, nonionic Metolose 65SH50 and cationic chitosan were included into tablets either by direct compression (DC) or after granulation with the probiotics. Disintegration, mucoadhesion of the tablets, and storage stability of the probiotics were characterized. RESULTS: By incorporating a sufficient amount of polymer superior probiotic mucoadhesion could be achieved. All formulations based on granulated probiotics and mucoadhesive polymer fulfilled the Food and Drug Administration (FDA) acceptance level for disintegration of orodispersible tablets. These formulations exhibited excellent storage stability under refrigerated conditions over 30 months. Interestingly, ODTs including Carbopol 971P NF still proved superior mucoadhesion after long-term storage, whereas the mucoadhesive effect of Metolose 65SH50 and chitosan declined markedly. CONCLUSIONS: The results of this study suggest that Carbopol 971P NF was the most appropriate polymer for a probiotic mucoadhesive ODT.


Asunto(s)
Polímeros/química , Probióticos , Adhesividad , Administración Bucal , Mucosa Bucal/efectos de los fármacos , Comprimidos
5.
Eur J Nucl Med Mol Imaging ; 42(3): 438-46, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25412766

RESUMEN

PURPOSE: Imaging of the 18-kDa translocator protein (TSPO) is a potential tool for examining microglial activation and neuroinflammation in early Alzheimer's disease (AD). [(18)F]FEMPA is a novel high-affinity second-generation TSPO radioligand that has displayed suitable pharmacokinetic properties in preclinical studies. The aims of this study were to quantify the binding of [(18)F]FEMPA to TSPO in AD patients and controls and to investigate whether higher [(18)F]FEMPA binding in AD patients than in controls could be detected in vivo. METHODS: Ten AD patients (five men, five women; age 66.9 ± 7.3 years; MMSE score 25.5 ± 2.5) and seven controls (three men, four women; age 63.7 ± 7.2 years, MMSE score 29.3 ± 1.0) were studied using [(18)F]FEMPA at Turku (13 subjects) and at Karolinska Institutet (4 subjects). The in vitro binding affinity for TSPO was assessed using PBR28 in a competition assay with [(3)H]PK11195 in seven controls and eight AD patients. Cortical and subcortical regions of interest were examined. Quantification was performed using a two-tissue compartment model (2TCM) and Logan graphical analysis (GA). The outcome measure was the total distribution volume (V T). Repeated measures analysis of variance was used to assess the effect of group and TSPO binding status on V T. RESULTS: Five AD patients and four controls were high-affinity binders (HABs). Three AD patients and three controls were mixed-affinity binders. V T estimated with Logan GA was significantly correlated with V T estimated with the 2TCM in both controls (r = 0.97) and AD patients (r = 0.98) and was selected for the final analysis. Significantly higher V T was found in the medial temporal cortex in AD patients than in controls (p = 0.044) if the TSPO binding status was entered as a covariate. If only HABs were included, significantly higher V T was found in the medial and lateral temporal cortex, posterior cingulate, caudate, putamen, thalamus and cerebellum in AD patients than in controls (p < 0.05). CONCLUSION: [(18)F]FEMPA seems to be a suitable radioligand for detecting increased TSPO binding in AD patients if their binding status is taken into account.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Hidrocarburos Fluorados , Tomografía de Emisión de Positrones , Piridinas , Radiofármacos , Receptores de GABA/metabolismo , Anciano , Femenino , Humanos , Hidrocarburos Fluorados/efectos adversos , Hidrocarburos Fluorados/farmacocinética , Masculino , Persona de Mediana Edad , Unión Proteica , Piridinas/efectos adversos , Piridinas/farmacocinética , Radiofármacos/efectos adversos , Radiofármacos/farmacocinética
6.
Planta Med ; 81(8): 670-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25519917

RESUMEN

Angiotensin II and endothelin-1 are potent vasoconstrictive peptides that play a central role in blood pressure regulation. Both peptides exert their pleiotropic effects via binding to their respective G-protein-coupled receptors, i.e., angiotensin AT1 and endothelin type A and type B receptors. In the present study, we have selected six structurally different plant-derived compounds with known cardioprotective properties to evaluate their ability to modulate calcium signaling of the above-mentioned receptors. For this purpose, we used and validated a cellular luminescence-based read-out system in which we measured intracellular calcium signaling in Chinese hamster ovary cells that express the calcium sensitive apo-aequorin protein. Firstly, silibinin, a flavanolignan that occurs in milk thistle (Silybum marianum), was investigated and found to be an antagonist for the human angiotensin AT1 receptor with an affinity constant of about 9 µM, while it had no effect on endothelin type A or type B receptor activation. Quercetin and crocin partially impeded intracellular calcium signaling resulting in a non-receptor-related reduction of the responses recorded for the three investigated G-protein-coupled receptors. Two organosulfur compounds, diallyl disulfide and diallyl trisulfide, as well as the triterpene saponin ginsenoside Rb1 did not affect the activation of the angiotensin AT1 and endothelin type A and type B receptors. In conclusion, we were able, by using a nonradioactive cellular read-out system, to identify a novel pharmacological property of the flavanolignan silibinin.


Asunto(s)
Antagonistas de Receptores de Angiotensina/farmacología , Señalización del Calcio/efectos de los fármacos , Antagonistas de los Receptores de Endotelina/farmacología , Endotelinas/efectos de los fármacos , Silimarina/farmacología , Compuestos Alílicos/farmacología , Angiotensina II/efectos de los fármacos , Angiotensinas/efectos de los fármacos , Animales , Células CHO , Carotenoides/farmacología , Cricetinae , Cricetulus , Endotelina-1/efectos de los fármacos , Femenino , Ginsenósidos/farmacología , Humanos , Quercetina/farmacología , Receptores de Angiotensina/efectos de los fármacos , Receptores de Endotelina/efectos de los fármacos , Silibina , Sulfuros/farmacología
7.
Proc Natl Acad Sci U S A ; 109(33): E2223-9, 2012 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-22745171

RESUMEN

During the primary response, the commitment of the CD8(+) T cell to Blimp-1 expression and the terminal differentiation that Blimp-1 induces must be timed so as not to impair the process of clonal expansion. We determined whether the Hippo pathway, which links cell-cell contact to differentiation in other cell lineages, controls Blimp-1 expression. Activating the CD8(+) T cell with antigen and IL-2 causes expression of the core Hippo pathway components, including the pivotal transcriptional cofactor Yap. Contact between activated CD8(+) T cells induces Hippo pathway-mediated Yap degradation and Blimp-1 expression; a Hippo-resistant, stable form of Yap suppresses Blimp-1 expression. Cytotoxic T lymphocyte antigen 4 (CTLA-4) and CD80 comprise the receptor-ligand pair that mediates contact-dependent Hippo pathway activation. In vivo, CD8(+) T cells expressing Hippo resistant-Yap or lacking CTLA-4 have diminished expression of the senescence marker, KLRG1, during a viral infection. The CTLA-4/Hippo pathway/Blimp-1 system may couple terminal differentiation of CD8(+) T cell with the magnitude of clonal expansion.


Asunto(s)
Linfocitos T CD8-positivos/enzimología , Linfocitos T CD8-positivos/inmunología , Antígeno CTLA-4/metabolismo , Activación de Linfocitos/inmunología , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/inmunología , Factores de Transcripción/metabolismo , Animales , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linfocitos T CD8-positivos/citología , Diferenciación Celular/inmunología , Membrana Celular/metabolismo , Activación Enzimática , Ligandos , Ratones , Factor 1 de Unión al Dominio 1 de Regulación Positiva
8.
Knee Surg Sports Traumatol Arthrosc ; 23(5): 1552-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24756537

RESUMEN

PURPOSE: In rotator cuff repair, strong and long-lasting suturing techniques that do not require additional implants are needed. This study examines the ultimate load to failure and the Young's modulus at the suture-tendon interface for a novel single-loop knot stitch and double-loop knot stitch. These values are compared to those of the modified Mason-Allen stitch. METHODS: Twenty-four infraspinatus muscles with tendons were dissected from porcine shoulders (twelve Goettingen minipigs). The preparations were randomly allocated to three groups of eight samples. Load-to-failure testing of the single-loop knot stitch, the double-loop knot stitch and the mMAS were performed using a Zwick 1446 universal testing machine (Zwick-Roell AG, Ulm, Germany). RESULTS: The highest ultimate load to failure for the three techniques occurred with the double-loop knot stitch with a median value of 382.2 N (range 291.8-454.2 N). These values were significantly higher than those of the single-loop knot stitch, which had a median value of 259.5 N (range 139.6-366.3 N) and the modified Mason-Allen stitch, which had a median value of 309.3 N (range 84.55-382.9 N). The values of the single-loop knot stitch and the modified Mason-Allen stitch did not differ significantly. Regarding the Young's modulus, no significant differences were found between the double-loop knot stitch with a median value of 496.02 N/mm² (range 400.4-572.6 N/mm²) and the modified Mason-Allen stitch with 498.5 N/mm² (range 375.5-749.2 N/mm²) with respect to the stiffness of the suture-tendon complex. The median value for the Young's modulus of the single-loop knot stitch of 392.1 N/mm² (range 285.7-510.6 N/mm²) was significantly lower than those of the double-loop knot stitch and modified Mason-Allen stitch. CONCLUSION: This in vitro animal study demonstrated that both the single-loop knot stitch and the double-loop knot stitch have excellent ultimate load-to-failure properties when used for rotator cuff repair. The introduced single-loop knot stitch and double-loop knot stitch offer an alternative to other common used stitch techniques in rotator cuff repair.


Asunto(s)
Artroscopía/métodos , Manguito de los Rotadores/cirugía , Técnicas de Sutura/instrumentación , Suturas , Animales , Modelos Animales de Enfermedad , Diseño de Equipo , Femenino , Lesiones del Manguito de los Rotadores , Porcinos , Porcinos Enanos
9.
Alzheimers Dement ; 11(8): 964-74, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25824567

RESUMEN

BACKGROUND: Evaluation of brain ß-amyloid by positron emission tomography (PET) imaging can assist in the diagnosis of Alzheimer disease (AD) and other dementias. METHODS: Open-label, nonrandomized, multicenter, phase 3 study to validate the (18)F-labeled ß-amyloid tracer florbetaben by comparing in vivo PET imaging with post-mortem histopathology. RESULTS: Brain images and tissue from 74 deceased subjects (of 216 trial participants) were analyzed. Forty-six of 47 neuritic ß-amyloid-positive cases were read as PET positive, and 24 of 27 neuritic ß-amyloid plaque-negative cases were read as PET negative (sensitivity 97.9% [95% confidence interval or CI 93.8-100%], specificity 88.9% [95% CI 77.0-100%]). In a subgroup, a regional tissue-scan matched analysis was performed. In areas known to strongly accumulate ß-amyloid plaques, sensitivity and specificity were 82% to 90%, and 86% to 95%, respectively. CONCLUSIONS: Florbetaben PET shows high sensitivity and specificity for the detection of histopathology-confirmed neuritic ß-amyloid plaques and may thus be a valuable adjunct to clinical diagnosis, particularly for the exclusion of AD. TRIAL REGISTRATION: ClinicalTrials.govNCT01020838.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides/metabolismo , Compuestos de Anilina/farmacocinética , Encéfalo , Placa Amiloide/patología , Estilbenos/farmacocinética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Análisis de Varianza , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Encéfalo/patología , Estudios de Cohortes , Diagnóstico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Escalas de Valoración Psiquiátrica , Curva ROC , Radiografía
10.
Eur J Nucl Med Mol Imaging ; 40(6): 921-31, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23436070

RESUMEN

PURPOSE: Imaging the 18-kDa translocator protein (TSPO) is considered a potential tool for in vivo evaluation of microglial activation and neuroinflammation in the early stages of Alzheimer's disease (AD). ((R)-1-(2-chlorophenyl)-N-[(11)C]-methyl-N-(1-methylpropyl)-3-isoquinoline caboxamide ([(11)C]-(R)-PK11195) has been widely used for PET imaging of TSPO and, despite its low specific-to-nondisplaceable binding ratio, increased TSPO binding has been shown in AD patients. The high-affinity radioligand N-(5-fluoro-2-phenoxyphenyl)-N-(2-[(18)F]fluoroethyl-5-methoxybenzyl)acetamide ([(18)F]FEDAA1106) has been developed as a potential in vivo imaging tool for better quantification of TSPO binding. The aim of this study was to quantify in vivo binding of [(18)F]FEDAA1106 to TSPO in control subjects and AD patients. METHODS: Seven controls (five men, two women, age 68±3 years, MMSE score 29±1) and nine AD patients (six men, three women, age 69±4 years, MMSE score 25±3) were studied with [(18)F]FEDAA1106. PET measurements were performed on an ECAT EXACT HR system (Siemens Medical Solutions) in two 60-min dynamic PET sessions with a 30-min interval between sessions. Arterial blood radioactivity was measured using an automated blood sampling system for the first 5 min and using manually drawn samples thereafter. Quantification was performed using both kinetic analysis based on a two-tissue compartment model and Logan graphical analysis. Outcome measures were total distribution volume (V T) and binding potential (BP(ND)=k3/k4). An estimate of nondisplaceable distribution volume was obtained with the Logan graphical analysis using the first 15 min of PET measurements (V(ND 1-15 min)). Binding potential (BP(ND)) was also calculated as: V(T)/V(ND 1-15 min) - 1. RESULTS: No statistically significant differences in V(T), k3/k4 or BP(ND) were observed between controls and AD patients. CONCLUSION: This study suggests that TSPO imaging with [(18)F]FEDAA1106 does not enable the detection of microglial activation in AD.


Asunto(s)
Acetamidas/farmacología , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Fluorodesoxiglucosa F18/farmacología , Tomografía de Emisión de Positrones , Receptores de GABA/metabolismo , Anciano , Automatización , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Factores de Tiempo , Distribución Tisular , Resultado del Tratamiento
11.
Sci Total Environ ; 858(Pt 1): 159433, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36244489

RESUMEN

Fatal dog poisoning after uptake of neurotoxic cyanobacteria associated with aquatic macrophytes in Tegeler See (Berlin, Germany) raised concerns about critical exposure of humans, especially children, to cyanotoxins produced by macrophyte associated cyanobacteria during recreational activity. From 2017 to 2021 a total of 398 samples of macrophytes washed ashore at bathing sites located at 19 Berlin lakes were analysed for anatoxins, microcystins, and cylindrospermopsins, as were 463 water samples taken in direct proximity to macrophyte accumulations. Cyanotoxins were detected in 66 % of macrophyte samples and 50 % of water samples, with anatoxins being the most frequently detected toxin group in macrophyte samples (58 %) and cylindrospermopsins in water samples (41 %). Microcoleus sp. associated with the water moss Fontinalis antipyretica was identified as anatoxin producing cyanobacterium in isolated strains as well as in field samples from Tegeler See. Anatoxin contents in macrophyte samples rarely exceeded 1 µg/g macrophyte fresh weight and peaked at 9. 2 µg/g f.w. Based on established toxicological points of departure, a critical anatoxin content of macrophyte samples of 3 µg/g f.w. is proposed. Five samples, all taken in Tegeler See and all associated with the water moss Fontinalis antipyretica, exceeded this value. Contents and concentrations of microcystins and cylindrospermopsins did not reach critical levels. The potential exposure risks to anatoxins for children and dogs are assessed and recommendations are given.


Asunto(s)
Toxinas Bacterianas , Cianobacterias , Niño , Humanos , Perros , Animales , Microcistinas/análisis , Toxinas de Cianobacterias , Berlin , Toxinas Bacterianas/análisis , Medición de Riesgo , Agua/análisis
12.
Photochem Photobiol ; 99(2): 716-731, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36004389

RESUMEN

Many studies show that photodynamic inactivation (PDI) is a powerful tool for the fight against pathogenic, multiresistant bacteria and the closing of hygiene gaps. However, PDI studies have been frequently performed under standardized in vitro conditions comprising artificial laboratory settings. Under real-life conditions, however, PDI encounters substances like ions, proteins, amino acids and fatty acids, potentially hampering the efficacy of PDI to an unpredictable extent. Thus, we investigated PDI with the phenalene-1-one-based photosensitizer SAPYR against Escherichia coli and Staphylococcus aureus in the presence of calcium or magnesium ions, which are ubiquitous in potential fields of PDI applications like in tap water or on tissue surfaces. The addition of citrate should elucidate the potential as a chelator. The results indicate that PDI is clearly affected by such ubiquitous ions depending on its concentration and the type of bacteria. The application of citrate enhanced PDI, especially for Gram-negative bacteria at certain ionic concentrations (e.g. CaCl2 or MgCl2 : 7.5 to 75 mmol L-1 ). Citrate also improved PDI efficacy in tap water (especially for Gram-negative bacteria) and synthetic sweat solution (especially for Gram-positive bacteria). In conclusion, the use of chelating agents like citrate may facilitate the application of PDI under real-life conditions.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/química , Ácido Cítrico/farmacología , Quelantes/farmacología , Staphylococcus aureus , Citratos/farmacología , Agua , Fotoquimioterapia/métodos
13.
ChemMedChem ; 18(16): e202300182, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37377066

RESUMEN

We compared the anti-influenza potencies of 57 adamantyl amines and analogs against influenza A virus with serine-31 M2 proton channel, usually termed as WT M2 channel, which is amantadine sensitive. We also tested a subset of these compounds against viruses with the amantadine-resistant L26F, V27A, A30T, G34E M2 mutant channels. Four compounds inhibited WT M2 virus in vitro with mid-nanomolar potency, with 27 compounds showing sub-micromolar to low micromolar potency. Several compounds inhibited L26F M2 virus in vitro with sub-micromolar to low micromolar potency, but only three compounds blocked L26F M2-mediated proton current as determined by electrophysiology (EP). One compound was found to be a triple blocker of WT, L26F, V27A M2 channels by EP assays, but did not inhibit V27A M2 virus in vitro, and one compound inhibited WT, L26F, V27A M2 in vitro without blocking V27A M2 channel. One compound blocked only L26F M2 channel by EP, but did not inhibit virus replication. The triple blocker compound is as long as rimantadine, but could bind and block V27A M2 channel due to its larger girth as revealed by molecular dynamics simulations, while MAS NMR informed on the interaction of the compound with M2(18-60) WT or L26F or V27A.


Asunto(s)
Gripe Humana , Simulación de Dinámica Molecular , Humanos , Antivirales/química , Aminas/farmacología , Protones , Mutación , Gripe Humana/tratamiento farmacológico , Amantadina/farmacología , Amantadina/uso terapéutico , Proteínas de la Matriz Viral/química , Farmacorresistencia Viral
14.
Pain ; 164(11): 2528-2539, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37289573

RESUMEN

ABSTRACT: Chronic pelvic pain (CPP), despite its high prevalence, is still relatively poorly understood mechanistically. This study, as part of the Translational Research in Pelvic Pain (TRiPP) project, has used a full quantitative sensory testing (QST) paradigm to profile n = 85 women with and without CPP (endometriosis or bladder pain specifically). We used the foot as a control site and abdomen as the test site. Across 5 diagnostically determined subgroups, we found features which are common across different aetiologies, eg, gain of function in pressure pain threshold (PPT) when assessing responses from the lower abdomen or pelvis (referred pain site). However, disease-specific phenotypes were also identified, eg, greater mechanical allodynia in endometriosis, despite there being large heterogeneities within diagnostic groups. The most common QST sensory phenotype was mechanical hyperalgesia (>50% across all the groups). A "healthy' sensory phenotype was seen in <7% of CPP participants. Specific QST measures correlated with sensory symptoms assessed by the painDETECT questionnaire (pressure-evoked pain [painDETECT] and PPT [QST] [ r = 0.47, P < 0.001]; mechanical hyperalgesia (painDETECT) and mechanical pain sensitivity [MPS from QST] [ r = 0.38, P = 0.009]). The data suggest that participants with CPP are sensitive to both deep tissue and cutaneous inputs, suggesting that central mechanisms may be important in this cohort. We also see phenotypes such as thermal hyperalgesia, which may be the result of peripheral mechanisms, such as irritable nociceptors. This highlights the importance of stratifying patients into clinically meaningful phenotypes, which may have implications for the development of better therapeutic strategies for CPP.


Asunto(s)
Dolor Crónico , Endometriosis , Humanos , Femenino , Hiperalgesia , Dimensión del Dolor/métodos , Investigación Biomédica Traslacional , Umbral del Dolor/fisiología , Dolor Pélvico , Dolor Crónico/diagnóstico
15.
EMBO J ; 27(11): 1622-32, 2008 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-18497744

RESUMEN

Ribosome-associated chaperone Trigger Factor (TF) initiates folding of newly synthesized proteins in bacteria. Here, we pinpoint by site-specific crosslinking the sequence of molecular interactions of Escherichia coli TF and nascent chains during translation. Furthermore, we provide the first full-length structure of TF associated with ribosome-nascent chain complexes by using cryo-electron microscopy. In its active state, TF arches over the ribosomal exit tunnel accepting nascent chains in a protective void. The growing nascent chain initially follows a predefined path through the entire interior of TF in an unfolded conformation, and even after folding into a domain it remains accommodated inside the protective cavity of ribosome-bound TF. The adaptability to accept nascent chains of different length and folding states may explain how TF is able to assist co-translational folding of all kinds of nascent polypeptides during ongoing synthesis. Moreover, we suggest a model of how TF's chaperoning function can be coordinated with the co-translational processing and membrane targeting of nascent polypeptides by other ribosome-associated factors.


Asunto(s)
Proteínas de Escherichia coli/química , Chaperonas Moleculares/química , Isomerasa de Peptidilprolil/química , Biosíntesis de Proteínas , Ribosomas/química , Secuencia de Aminoácidos , Reactivos de Enlaces Cruzados/química , Microscopía por Crioelectrón , Péptidos/química , Conformación Proteica , Pliegue de Proteína , Estructura Terciaria de Proteína
16.
Mol Plant ; 15(2): 363-371, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34848348

RESUMEN

Seed size critically affects grain yield of crops and hence represents a key breeding target. The development of embryo-nourishing endosperm is a key driver of seed expansion. We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size. These EIN3 functions have remained largely undiscovered because they oppose each other. Capitalizing on the analysis of multiple ethylene biosynthesis mutants, we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene. We, in addition, provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion. Interestingly, synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants, suggesting that this promoting function of EIN3 is independent of ethylene. Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue, the growth-promoting role of EIN3 is induced by fertilization, revealing a generation conflict that converges toward the key signaling component EIN3.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fitomejoramiento , Semillas/genética , Semillas/metabolismo
17.
Biochim Biophys Acta ; 1803(6): 650-61, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20132842

RESUMEN

Newly synthesized proteins often require the assistance of molecular chaperones to efficiently fold into functional three-dimensional structures. At first, ribosome-associated chaperones guide the initial folding steps and protect growing polypeptide chains from misfolding and aggregation. After that folding into the native structure may occur spontaneously or require support by additional chaperones which do not bind to the ribosome such as DnaK and GroEL. Here we review the current knowledge on the best-characterized ribosome-associated chaperone at present, the Escherichia coli Trigger Factor. We describe recent progress on structural and dynamic aspects of Trigger Factor's interactions with the ribosome and substrates and discuss how these interactions affect co-translational protein folding. In addition, we discuss the newly proposed ribosome-independent function of Trigger Factor as assembly factor of multi-subunit protein complexes. Finally, we cover the functional cooperation between Trigger Factor, DnaK and GroEL in folding of cytosolic proteins and the interplay between Trigger Factor and other ribosome-associated factors acting in enzymatic processing and translocation of nascent polypeptide chains.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Ribosomas/metabolismo , Chaperonina 60/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas de Choque Térmico/metabolismo , Cinética , Modelos Biológicos , Conformación Molecular , Péptidos/química , Fenotipo , Pliegue de Proteína , Transporte de Proteínas , Relación Estructura-Actividad , Especificidad por Sustrato
18.
Eur J Nucl Med Mol Imaging ; 38(11): 2058-65, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21732107

RESUMEN

PURPOSE: [(18)F]FEDAA1106 is a recently developed positron emission tomography (PET) radioligand for in vivo quantification of the 18 kDa translocator protein [TSPO or, as earlier called, the peripheral benzodiazepine receptor (PBR)]. TSPO imaging is expected to be useful for the clinical evaluation of neuroinflammatory diseases. The aim of this study was to provide dosimetry estimates for [(18)F]FEDAA1106 based on human whole-body PET measurements. METHODS: PET scans were performed for a total of 6.6 h after the injection of 183.8 ± 9.1 MBq of [(18)F]FEDAA1106 in six healthy subjects. Regions of interest were drawn on coronal images. Estimates of the absorbed doses of radiation were calculated using the OLINDA software. RESULTS: Peak uptake was largest in lungs, followed by liver, small intestine, kidney, spleen and other organs. Peak values of the percent injected dose (%ID) at a time after radioligand injection were calculated for the lungs (27.1%ID at 0.2 h), liver (21.1%ID at 0.6 h), small intestine (10.4%ID at 6.3 h), kidney (4.9%ID at 1.8 h) and spleen (4.6%ID at 0.6 h). The largest absorbed dose was found in the spleen (0.12 mSv/MBq), followed by kidneys (0.094 mSv/MBq). The calculated mean effective dose was 0.036 mSv/MBq. CONCLUSION: Based on the distribution and dose estimates, the estimated radiation burden of [(18)F]FEDAA1106 is moderately higher than that of [(18)F]fluorodeoxyglucose (FDG). In clinical studies, the administered activity of this radioligand ought to be adjusted in line with regional regulations. This result would be helpful for further clinical TSPO imaging studies.


Asunto(s)
Acetamidas/metabolismo , Acetamidas/farmacocinética , Tomografía de Emisión de Positrones , Receptores de GABA/metabolismo , Imagen de Cuerpo Entero , Anciano , Femenino , Humanos , Ligandos , Masculino , Dosis de Radiación , Radiometría
19.
Cancers (Basel) ; 13(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34638268

RESUMEN

Clinical translation of novel immunotherapeutic strategies such as chimeric antigen receptor (CAR) T-cells in acute myeloid leukemia (AML) is still at an early stage. Major challenges include immune escape and disease relapse demanding for further improvements in CAR design. To overcome such hurdles, we have invented the switchable, flexible and programmable adaptor Reverse (Rev) CAR platform. This consists of T-cells engineered with RevCARs that are primarily inactive as they express an extracellular short peptide epitope incapable of recognizing surface antigens. RevCAR T-cells can be redirected to tumor antigens and controlled by bispecific antibodies cross-linking RevCAR T- and tumor cells resulting in tumor lysis. Remarkably, the RevCAR platform enables combinatorial tumor targeting following Boolean logic gates. We herein show for the first time the applicability of the RevCAR platform to target myeloid malignancies like AML. Applying in vitro and in vivo models, we have proven that AML cell lines as well as patient-derived AML blasts were efficiently killed by redirected RevCAR T-cells targeting CD33 and CD123 in a flexible manner. Furthermore, by targeting both antigens, a Boolean AND gate logic targeting could be achieved using the RevCAR platform. These accomplishments pave the way towards an improved and personalized immunotherapy for AML patients.

20.
Pain ; 162(9): 2349-2365, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34448751

RESUMEN

ABSTRACT: Endometriosis (ENDO) and interstitial cystitis/bladder pain syndrome (IC/BPS) are chronic pain conditions for which better treatments are urgently needed. Development of new therapies with proven clinical benefit has been slow. We have conducted a review of existing preclinical in vivo models for ENDO and IC/BPS in rodents, discussed to what extent they replicate the phenotype and pain experience of patients, as well as their relevance for translational research. In 1009 publications detailing ENDO models, 41% used autologous, 26% syngeneic, 18% xenograft, and 11% allogeneic tissue in transplantation models. Intraperitoneal injection of endometrial tissue was the subcategory with the highest construct validity score for translational research. From 1055 IC/BPS publications, most interventions were bladder centric (85%), followed by complex mechanisms (8%) and stress-induced models (7%). Within these categories, the most frequently used models were instillation of irritants (92%), autoimmune (43%), and water avoidance stress (39%), respectively. Notably, although pelvic pain is a hallmark of both conditions and a key endpoint for development of novel therapies, only a small proportion of the studies (models of ENDO: 0.5%-12% and models of IC/BPS: 20%-44%) examined endpoints associated with pain. Moreover, only 2% and 3% of publications using models of ENDO and IC/BPS investigated nonevoked pain endpoints. This analysis highlights the wide variety of models used, limiting reproducibility and translation of results. We recommend refining models so that they better reflect clinical reality, sharing protocols, and using standardized endpoints to improve reproducibility. We are addressing this in our project Innovative Medicines Initiative-PainCare/Translational Research in Pelvic Pain.


Asunto(s)
Cistitis Intersticial , Endometriosis , Cistitis Intersticial/terapia , Femenino , Humanos , Dolor Pélvico/terapia , Reproducibilidad de los Resultados , Investigación Biomédica Traslacional
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