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1.
Respir Res ; 21(1): 238, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943048

RESUMO

BACKGROUND: Previously, it has been shown that obesity is a risk factor for recovery, regeneration, and tissue repair after blunt trauma and can affect the rate of muscle recovery and collagen deposition after trauma. To date, lung tissue regeneration and extracellular matrix regulation in obese mice after injury has not been investigated in detail yet. METHODS: This study uses an established blunt thorax trauma model to analyze morphological changes and alterations on gene and protein level in lean or obese (diet-induced obesity for 16 ± 1 week) male C57BL/6 J mice at various time-points after trauma induction (1 h, 6 h, 24 h, 72 h and 192 h). RESULTS: Morphological analysis after injury showed lung parenchyma damage at early time-points in both lean and obese mice. At later time-points a better regenerative capacity of lean mice was observed, since obese animals still exhibited alveoli collapse, wall thickness as well as remaining filled alveoli structures. Although lean mice showed significantly increased collagen and fibronectin gene levels, analysis of collagen deposition showed no difference based on colorimetric quantification of collagen and visual assessment of Sirius red staining. When investigating the organization of the ECM on gene level, a decreased response of obese mice after trauma regarding extracellular matrix composition and organization was detectable. Differences in the lung tissue between the diets regarding early responding MMPs (MMP8/9) and late responding MMPs (MMP2) could be observed on gene and protein level. Obese mice show differences in regulation of extracellular matrix components compared to normal weight mice, which results in a decreased total MMP activity in obese animals during the whole regeneration phase. Starting at 6 h post traumatic injury, lean mice show a 50% increase in total MMP activity compared to control animals, while MMP activity in obese mice drops to 50%. CONCLUSIONS: In conclusion, abnormal regulation of the levels of extracellular matrix genes in the lung may contribute to an aberrant regeneration after trauma induction with a delay of repair and pathological changes of the lung tissue in obese mice.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Matriz Extracelular/patologia , Pulmão/patologia , Obesidade/patologia , Traumatismos Torácicos/patologia , Ferimentos não Penetrantes/patologia , Animais , Dieta Hiperlipídica/efeitos adversos , Dieta Hiperlipídica/tendências , Matriz Extracelular/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/metabolismo , Traumatismos Torácicos/complicações , Traumatismos Torácicos/metabolismo , Tórax , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/metabolismo
2.
J Cell Sci ; 129(12): 2416-29, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27179075

RESUMO

Dynamic regulation of cell-cell adhesion by the coordinated formation and dissolution of E-cadherin-based adherens junctions is crucial for tissue homeostasis. The actin-binding protein cortactin interacts with E-cadherin and enables F-actin accumulation at adherens junctions. Here, we were interested to study the broader functional interactions of cortactin in adhesion complexes. In line with literature, we demonstrate that cortactin binds to E-cadherin, and that a posttranslational modification of cortactin, RhoA-induced phosphorylation by protein kinase D1 (PKD1; also known as PRKD1) at S298, impairs adherens junction assembly and supports their dissolution. Two new S298-phosphorylation-dependent interactions were also identified, namely, that phosphorylation of cortactin decreases its interaction with ß-catenin and the actin-binding protein vinculin. In addition, binding of vinculin to ß-catenin, as well as linkage of vinculin to F-actin, are also significantly compromised upon phosphorylation of cortactin. Accordingly, we found that regulation of cell-cell adhesion by phosphorylation of cortactin downstream of RhoA and PKD1 is vitally dependent on vinculin-mediated protein interactions. Thus, cortactin, unexpectedly, is an important integration node for the dynamic regulation of protein complexes during breakdown and formation of adherens junctions.


Assuntos
Caderinas/metabolismo , Cortactina/metabolismo , Canais de Cátion TRPP/metabolismo , Citoesqueleto de Actina/metabolismo , Junções Aderentes/metabolismo , Animais , Antígenos CD , Células CACO-2 , Adesão Celular , Colo/metabolismo , Epitélio/metabolismo , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Fosforilação , Fosfosserina/metabolismo , Vinculina/metabolismo
3.
BMC Cancer ; 18(1): 140, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29409464

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the fourth leading cause of cancer related deaths worldwide and prognosis in advanced tumor stage still remains poor. Since CK1 isoforms have been reported to be deregulated in several tumor entities CK1 has emerged as a novel drug target in cancer therapy. In this study we set out to investigate whether CK1α might have the potential to serve as prognostic marker. METHODS: CK1α RNA and protein expression levels in healthy and tumor tissue of CRC patients were analyzed using quantitative real-time PCR and Western Blot analysis, respectively. Prognostic relevance was investigated by correlating obtained CK1α expression levels with patients' survival rate generating Kaplan-Meier survival plots. RESULTS: It could be shown that CK1α is overexpressed in colorectal tumor tissue compared to normal tissue and CK1α overexpression in tumor tissue correlates with poor survival in CRC patients. Results become more significant when only considering patients with high-grade tumors, as well as patients assigned to UICC II and UICC III stage. Furthermore, Cox regression analysis revealed that CK1α is an independent prognostic factor. In addition, tumors expressing decreased levels of the kinase reveal positive effects on overall survival when localized in the right colon compared to those in the left side. CONCLUSION: In summary, this study provides evidence for the first time that CK1α RNA levels might serve as prognostic marker for CRC.


Assuntos
Biomarcadores Tumorais/genética , Caseína Quinase Ialfa/genética , Neoplasias Colorretais/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Caseína Quinase Ialfa/metabolismo , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
4.
Arch Toxicol ; 92(1): 323-336, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28924833

RESUMO

Bacterial protein toxins became valuable molecular tools for the targeted modulation of cell functions in experimental pharmacology and attractive therapeutics because of their potent and specific mode of action in human cells. C2IN-C3lim, a recombinant fusion toxin (~50 kDa) of the Rho-inhibiting C3lim from Clostridium (C.) limosum and a non-toxic portion of the C. botulinum C2 toxin (C2IN), is selectively internalized into the cytosol of monocytic cells where C3lim specifically ADP-ribosylates Rho A and -B, thereby inhibiting Rho-mediated signaling. Thus, we hypothesized that these unique features make C2IN-C3lim an attractive molecule for the targeted pharmacological down-regulation of Rho-mediated functions in monocytes. The analysis of the actin structure and the Rho ADP-ribosylation status implied that C2IN-C3lim entered the cytosol of primary human monocytes from healthy donors ex vivo within 1 h. Moreover, it inhibited the fMLP-induced chemotaxis of human monocytes in a Boyden chamber model ex vivo. Similarly, in a 3-dimensional ex vivo model of extravasation, single cell analysis revealed that C2IN-C3lim-treated cells were not able to move. In a clinically relevant mouse model of blunt chest trauma, the local application of C2IN-C3lim into the lungs after thorax trauma prevented the trauma-induced recruitment of monocytes into the lungs in vivo. Thus, C2IN-C3lim might be an attractive lead compound for novel pharmacological strategies to avoid the cellular damage response caused by monocytes in damaged tissue after trauma and during systemic inflammation. The results suggest that the pathophysiological role of clostridial C3 toxins might be a down-modulation of the innate immune system.


Assuntos
ADP Ribose Transferases/genética , Toxinas Botulínicas/genética , Quimiotaxia/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Monócitos/citologia , Proteínas Recombinantes de Fusão/genética , Traumatismos Torácicos/tratamento farmacológico , Ferimentos não Penetrantes/tratamento farmacológico , Proteínas rho de Ligação ao GTP/metabolismo
5.
Int J Mol Sci ; 19(9)2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30200215

RESUMO

Colon cancer (CC) and rectal cancer (RC) are synonymously called colorectal cancer (CRC). Based on our experience in basic and clinical research as well as routine work in the field, the term CRC should be abandoned. We analyzed the available data from the literature and results from our multicenter Research Group Oncology of Gastrointestinal Tumors termed FOGT to confirm or reject this hypothesis. Anatomically, the risk of developing RC is four times higher than CC, while physical activity helps to prevent CC but not RC. Obvious differences exist in molecular carcinogenesis, pathology, surgical topography and procedures, and multimodal treatment. Therefore, we conclude that CC is not the same as RC. The term "CRC" should no longer be used as a single entity in basic and clinical research as well as other areas of classification.


Assuntos
Neoplasias do Colo/patologia , Neoplasias Retais/patologia , Neoplasias do Colo/epidemiologia , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Terapia Combinada , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Estudos Multicêntricos como Assunto , Especificidade de Órgãos , Neoplasias Retais/epidemiologia , Neoplasias Retais/genética , Neoplasias Retais/terapia , Fatores de Risco
6.
J Hand Ther ; 31(1): 20-28, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28438435

RESUMO

STUDY DESIGN: Prospective cohort randomized controlled trial. PURPOSE OF THE STUDY: Is either a home exercise (HE) program or traditional physical therapy (PT) more effective in the postoperative management of metacarpal fractures? METHODS: Sixty patients suffering from nonthumb metacarpal fractures who received mobilization-stable open reduction and internal fixation were included. All patients were prospectively randomized into either the PT group or the HE group. Follow-up examinations at 2, 6 and 12 weeks postoperatively. RESULTS: After 2 weeks, the range of motion (ROM) in both groups was still severely reduced. Twelve weeks after surgery the ROM improved to 245° (PT) and 256° (HE). Grip strength after 6 weeks was 68% (PT) and 71% (HE) when compared to the non-injured hand, improving to 91% (PT) and 93% (HE) after 12 weeks. CONCLUSION: Study results show that both HE program and traditional PT are effective in the postoperative management of metacarpal fractures. LEVEL OF EVIDENCE: II.


Assuntos
Terapia por Exercício , Fixação de Fratura/reabilitação , Fraturas Ósseas/reabilitação , Serviços de Assistência Domiciliar , Ossos Metacarpais/lesões , Cuidados Pós-Operatórios , Adolescente , Adulto , Feminino , Fraturas Ósseas/cirurgia , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Resultado do Tratamento , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-27795367

RESUMO

Ertapenem provides broad-spectrum activity against many pathogens, and its use is relevant for the prophylaxis and treatment of infections in morbidly obese patients undergoing surgery. However, its pharmacokinetics and tissue penetration in these patients are not well defined. We assessed the population pharmacokinetics and target attainment for ertapenem in the plasma, subcutaneous tissue, and peritoneal fluid of morbidly obese patients. Six female patients (body mass index, 43.7 to 55.9 kg/m2) received 1,000 mg ertapenem as 15-min infusions at 0 and 26 h. On day 2, the unbound ertapenem concentrations in plasma, subcutaneous tissue, and peritoneal fluid were measured by microdialysis; total plasma concentrations were additionally quantified. The probability of attaining a target of an unbound ertapenem concentration above the MIC for at least 40% of the dosing interval was predicted via Monte Carlo simulations. The population pharmacokinetic model contained two disposition compartments and simultaneously described all concentrations. For unbound ertapenem, total clearance was 12.3 liters/h (coefficient of variation, 21.6% for between-patient variability) and the volume of distribution at steady state was 57.8 liters in patients with a 53-kg fat-free mass. The area under the concentration-time curve (AUC) for ertapenem was 49% lower in subcutaneous tissue and 25% lower in peritoneal fluid than the unbound AUC in plasma. Tissue penetration was rapid (equilibration half-life, <15 min) and was variable in subcutaneous tissue. Short-term ertapenem infusions (1,000 mg every 24 h) achieved robust (>90%) target attainment probabilities for MICs of up to 1 mg/liter in plasma, 0.25 to 0.5 mg/liter in subcutaneous tissue, and 0.5 mg/liter in peritoneal fluid. Ertapenem presents an attractive choice for many pathogens relevant to morbidly obese patients undergoing surgery. (This study has been registered at ClinicalTrials.gov under identifier NCT01407965.).


Assuntos
Obesidade Mórbida/sangue , beta-Lactamas/farmacocinética , beta-Lactamas/uso terapêutico , Adulto , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Ertapenem , Feminino , Humanos , Laparoscopia , Testes de Sensibilidade Microbiana , Microdiálise , Pessoa de Meia-Idade , Método de Monte Carlo , Obesidade Mórbida/terapia
8.
Int J Mol Sci ; 18(4)2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28350325

RESUMO

Exogenous interleukin-4 (IL-4) has been demonstrated to affect the growth of different human malignancies including pancreatic cancer cells. The aim of our study was to determine the role of endogenously expressed IL-4-receptor-α-chain (IL-4Rα) in pancreatic cancer cells. IL-4Rα-suppression was achieved by generating Capan-1 cells stably expressing shRNA targeting IL-4Rα. The malignant phenotype was characterized by assessing growth properties, directional and non-directional cell movement in vitro and tumor growth in vivo. Signaling pathways were analyzed upon IL-4 and IL-13 stimulation of wildtype (WT) and control-transfected cells compared to IL-4Rα-knockdown cells. Silencing of IL-4Rα resulted in reduced anchorage-dependent cell growth (p < 0.05) and reduced anchorage-independent colony size (p < 0.001) in vitro. Moreover, cell movement and migration was inhibited. IL-4 and IL-13 stimulation of Capan-1-WT cells induced activation of similar pathways like stimulation with Insulin-like growth factor (IGF)-I. This activation was reduced after IL-4Rα downregulation while IGF-I signaling seemed to be enhanced in knockdown-clones. Importantly, IL-4Rα silencing also significantly suppressed tumor growth in vivo. The present study indicates that endogenously expressed IL-4 and IL-4Rα contribute to the malignant phenotype of pancreatic cancer cells by activating diverse pro-oncogenic signaling pathways. Addressing these pathways may contribute to the treatment of the disease.


Assuntos
Subunidade alfa de Receptor de Interleucina-4/genética , Interleucina-4/metabolismo , Neoplasias Pancreáticas/patologia , RNA Interferente Pequeno/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Predisposição Genética para Doença , Humanos , Técnicas In Vitro , Interleucina-3/metabolismo , Subunidade alfa de Receptor de Interleucina-4/antagonistas & inibidores , Camundongos , Transplante de Neoplasias , Neoplasias Pancreáticas/genética , Transdução de Sinais
9.
Curr Opin Gastroenterol ; 28(3): 209-16, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22450891

RESUMO

PURPOSE OF REVIEW: Keratins are a subgroup of intermediate filaments expressed in the epithelia. Keratins emerged as important tissue-protecting genes and keratin variants cause/predispose to development of more than 50 human disorders. Our review focuses on the importance of keratins in context of liver disease. RECENT FINDINGS: K8/K18 variants are found in approximately 4% of white population and predispose to development and adverse outcome of multiple liver diseases. K8/K18 are major constituents of Mallory-Denk bodies, that is inclusions found in alcoholic and nonalcoholic steatohepatitis (NASH) and dysregulated keratin expression, K8 hyperphosphorylation, misfolding and crosslinking via transglutaminase 2 facilitate aggregate formation. Necrosis-generated and apoptosis-generated keratin serum fragments are emerging as important noninvasive markers of multiple liver diseases, particularly NASH. Keratins are established markers of tumor origin and in hepatocellular carcinoma, K19 expression is associated with poor prognosis. SUMMARY: Keratins are established tumor markers and are widely used as noninvasive markers of liver injury. In addition, the data that have become available in recent years have greatly advanced our understanding of keratins as modifiers of liver disease development.


Assuntos
Queratina-18/metabolismo , Queratina-8/metabolismo , Hepatopatias/metabolismo , Fígado/metabolismo , Biomarcadores/metabolismo , Progressão da Doença , Suscetibilidade a Doenças , Feminino , Humanos , Queratina-18/genética , Queratina-8/genética , Fígado/patologia , Hepatopatias/genética , Hepatopatias/fisiopatologia , Masculino
10.
Proc Natl Acad Sci U S A ; 106(37): 15696-701, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19717452

RESUMO

Migration of cells is important for tissue maintenance, immune response, and often altered in disease. While biochemical aspects, including cell adhesion, have been studied in detail, much less is known about the role of the mechanical properties of cells. Previous measurement methods rely on contact with artificial surfaces, which can convolute the results. Here, we used a non-contact, microfluidic optical stretcher to study cell mechanics, isolated from other parameters, in the context of tissue infiltration by acute promyelocytic leukemia (APL) cells, which occurs during differentiation therapy with retinoic acid. Compliance measurements of APL cells reveal a significant softening during differentiation, with the mechanical properties of differentiated cells resembling those of normal neutrophils. To interfere with the migratory ability acquired with the softening, differentiated APL cells were exposed to paclitaxel, which stabilizes microtubules. This treatment does not alter compliance but reduces cell relaxation after cessation of mechanical stress six-fold, congruent with a significant reduction of motility. Our observations imply that the dynamical remodeling of cell shape required for tissue infiltration can be frustrated by stiffening the microtubular system. This link between the cytoskeleton, cell mechanics, and motility suggests treatment options for pathologies relying on migration of cells, notably cancer metastasis.


Assuntos
Movimento Celular/fisiologia , Células Mieloides/citologia , Células Mieloides/fisiologia , Citoesqueleto de Actina/fisiologia , Fenômenos Biomecânicos , Fenômenos Biofísicos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Complacência (Medida de Distensibilidade)/efeitos dos fármacos , Complacência (Medida de Distensibilidade)/fisiologia , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/patologia , Leucemia Promielocítica Aguda/fisiopatologia , Técnicas Analíticas Microfluídicas , Microtúbulos/efeitos dos fármacos , Microtúbulos/fisiologia , Células Mieloides/efeitos dos fármacos , Paclitaxel/farmacologia , Tretinoína/farmacologia , Moduladores de Tubulina/farmacologia
11.
Sci Rep ; 12(1): 7053, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488042

RESUMO

Cell migration plays an essential role in wound healing and inflammatory processes inside the human body. Peripheral blood neutrophils, a type of polymorphonuclear leukocyte (PMN), are the first cells to be activated during inflammation and subsequently migrate toward an injured tissue or infection site. This response is dependent on both biochemical signaling and the extracellular environment, one aspect of which includes increased temperature in the tissues surrounding the inflammation site. In our study, we analyzed temperature-dependent neutrophil migration using differentiated HL-60 cells. The migration speed of differentiated HL-60 cells was found to correlate positively with temperature from 30 to 42 °C, with higher temperatures inducing a concomitant increase in cell detachment. The migration persistence time of differentiated HL-60 cells was higher at lower temperatures (30-33 °C), while the migration persistence length stayed constant throughout the temperature range. Coupled with the increased speed observed at high temperatures, this suggests that neutrophils are primed to migrate more effectively at the elevated temperatures characteristic of inflammation. Temperature gradients exist on both cell and tissue scales. Taking this into consideration, we also investigated the ability of differentiated HL-60 cells to sense and react to the presence of temperature gradients, a process known as thermotaxis. Using a two-dimensional temperature gradient chamber with a range of 27-43 °C, we observed a migration bias parallel to the gradient, resulting in both positive and negative thermotaxis. To better mimic the extracellular matrix (ECM) environment in vivo, a three-dimensional collagen temperature gradient chamber was constructed, allowing observation of biased neutrophil-like differentiated HL-60 migration toward the heat source.


Assuntos
Inflamação , Neutrófilos , Movimento Celular , Células HL-60 , Humanos , Temperatura
12.
Nat Cell Biol ; 5(9): 803-11, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12942086

RESUMO

Sphingosylphosphorylcholine (SPC) is a naturally occurring bioactive lipid that is present in high density lipoproteins (HDL) particles and found at increased levels in blood and malignant ascites of patients with ovarian cancer. Here, we show that incubation of human epithelial tumour cells with SPC induces a perinuclear reorganization of intact keratin 8-18 filaments. This effect is specific for SPC, largely independent of F-actin and microtubules, and is accompanied by keratin phosphorylation. In vivo visco-elastic probing of single cancer cells demonstrates that SPC increases cellular elasticity. Accordingly, SPC stimulates migration of cells through size-limited pores in a more potent manner than lysophosphatidic acid (LPA). LPA induces actin stress fibre formation, but does not reorganize keratins in cancer cells and hence increases cellular stiffness. We propose that reorganization of keratin by SPC may facilitate biological phenomena that require a high degree of elasticity, such as squeezing of cells through membranous pores during metastasis.


Assuntos
Carcinoma/metabolismo , Citoesqueleto/metabolismo , Queratinas/metabolismo , Neoplasias Pancreáticas/metabolismo , Fosforilcolina/análogos & derivados , Fosforilcolina/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Células Tumorais Cultivadas/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/ultraestrutura , Carcinoma/fisiopatologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Tamanho Celular/efeitos dos fármacos , Tamanho Celular/fisiologia , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Elasticidade/efeitos dos fármacos , Imunofluorescência , Humanos , Queratinas/efeitos dos fármacos , Queratinas/ultraestrutura , Microscopia Eletrônica , Metástase Neoplásica/fisiopatologia , Neoplasias Pancreáticas/fisiopatologia , Fosforilcolina/farmacologia , Esfingosina/farmacologia , Estresse Mecânico , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/ultraestrutura
13.
PLoS One ; 16(7): e0254165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234360

RESUMO

The cellular cortex is an approximately 200-nm-thick actin network that lies just beneath the cell membrane. It is responsible for the mechanical properties of cells, and as such, it is involved in many cellular processes, including cell migration and cellular interactions with the environment. To develop a clear view of this dense structure, high-resolution imaging is essential. As one such technique, electron microscopy, involves complex sample preparation procedures. The final drying of these samples has significant influence on potential artifacts, like cell shrinkage and the formation of artifactual holes in the actin cortex. In this study, we compared the three most used final sample drying procedures: critical-point drying (CPD), CPD with lens tissue (CPD-LT), and hexamethyldisilazane drying. We show that both hexamethyldisilazane and CPD-LT lead to fewer artifactual mesh holes within the actin cortex than CPD. Moreover, CPD-LT leads to significant reduction in cell height compared to hexamethyldisilazane and CPD. We conclude that the final drying procedure should be chosen according to the reduction in cell height, and so CPD-LT, or according to the spatial separation of the single layers of the actin cortex, and so hexamethyldisilazane.


Assuntos
Actinas/química , Liofilização/métodos , Microscopia Eletrônica de Varredura/métodos , Compostos de Organossilício/química , Artefatos , Células Cultivadas , Dessecação/métodos , Humanos , Manejo de Espécimes/métodos
14.
Adv Sci (Weinh) ; 8(24): e2102381, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34713625

RESUMO

Trauma is the leading cause of death in individuals under 44 years of age. Thorax trauma (TxT) is strongly associated with trauma-related death, an unbalanced innate immune response, sepsis, acute respiratory distress syndrome, and multiple organ dysfunction. It is shown that different in vivo traumata, such as TxT or an in vitro polytrauma cytokine cocktail trigger secretion of small extracellular nanovesicles (sEVs) from endothelial cells with pro-inflammatory cargo. These sEVs transfer transcripts for ICAM-1, VCAM-1, E-selectin, and cytokines to systemically activate the endothelium, facilitate neutrophil-endothelium interactions, and destabilize barrier integrity. Inhibition of sEV-release after TxT in mice ameliorates local as well as systemic inflammation, neutrophil infiltration, and distant organ damage in kidneys (acute kidney injury, AKI). Vice versa, injection of TxT-plasma-sEVs into healthy animals is sufficient to trigger pulmonary and systemic inflammation as well as AKI. Accordingly, increased sEV concentrations and transfer of similar cargos are observed in polytrauma patients, suggesting a fundamental pathophysiological mechanism.


Assuntos
Células Endoteliais/imunologia , Vesículas Extracelulares/imunologia , Inflamação/imunologia , Inflamação/fisiopatologia , Traumatismo Múltiplo/complicações , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/imunologia , Injúria Renal Aguda/fisiopatologia , Animais , Modelos Animais de Doenças , Células Endoteliais/fisiologia , Vesículas Extracelulares/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo Múltiplo/imunologia , Infiltração de Neutrófilos/fisiologia , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/fisiopatologia , Sepse/etiologia , Sepse/imunologia , Sepse/fisiopatologia
15.
Visc Med ; 35(2): 124-132, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31192246

RESUMO

BACKGROUND: There is still the need to optimize adjuvant treatment of colon cancer (CC). Standard adjuvant chemotherapy using 5-fluorouracil (FU) and folinic acid (FA) was compared with a combination including irinotecan (Folfiri). The aim of the present report was to analyze overall survival (OS) after long-term follow-up, to summarize final recurrence rates and toxicity data, and to identify possible clinical and pathological factors associated with prognosis. METHODS: Patients (CC stage IIb and III) were randomized to a 6-month treatment with FUFA or Folfiri. The trial was closed after 275 of 588 planned patients, 269 of which were included in the intention-to-treat analysis. RESULTS: 133 and 136 patients received FUFA and Folfiri, respectively. Adjuvant therapy was not completed for 16 FUFA (12.0%) and 44 Folfiri (32.4%) patients. Toxicities grade III and IV were observed in 17 (12.8%) patients treated with FUFA and in 50 (36.8%) patients treated with Folfiri. Recurrences occurred in 46 of 133 (34.6%) and in 47 of 136 (34.6%) patients who received FUFA and Folfiri, respectively. 5-year OS rates were 69.9% (95% confidence interval (CI): 61.2-77.1) for FUFA and 72.7% (95% CI: 63.9-79.8) for Folfiri. OS was associated with tumor grading (1 & 2 vs. 3), tumor sub-stage (II vs. IIIa vs. IIIb vs. IIIc), and tumor location (left vs. right colon). CONCLUSION: Folfiri cannot be generally recommended for adjuvant chemotherapy of CC. Besides tumor grading and sub-staging, prognosis of CC may depend on tumor location. Left-sided tumors had a significantly better prognosis irrespective of treatment.

16.
Cell Signal ; 19(2): 367-77, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16978842

RESUMO

Sphingosylphosphorylcholine (SPC) is the major component of high-density lipoproteins (HDL) in blood plasma. The bioactive lipid acts mainly via G protein coupled receptors (GPCRs). Similar to ligands of other GPCRs, SPC has multiple biological roles including the regulation of proliferation, migration, angiogenesis, wound healing and heart rate. Lysophospholipids and their receptors have also been implicated in cell differentiation. A potential role of SPC in stem cell or tumour cell differentiation has been elusive so far. Here we examined the effect of SPC on the differentiation of mouse embryonic stem (ES) cells and of human NB4 promyelocytic leukemia cells, a well established tumour differentiation model. Our data show that mouse embryonic stem cells and NB4 cells express the relevant GPCRs for SPC. We demonstrate both at the level of morphology and of gene expression that SPC induces neuronal and cardiac differentiation of mouse ES cells. Furthermore, SPC induces differentiation of NB4 cells by a mechanism which is critically dependent on the activity of the MEK-ERK cascade. Thus, the bioactive lipid SPC is a novel differentiation inducing agent both for mouse ES cells, but also of certain human tumour cells.


Assuntos
Células-Tronco Embrionárias/fisiologia , Leucemia Promielocítica Aguda/metabolismo , Fosforilcolina/análogos & derivados , Receptores Acoplados a Proteínas G/metabolismo , Esfingosina/análogos & derivados , Actinas/metabolismo , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Linhagem da Célula , Células-Tronco Embrionárias/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Adesões Focais , Humanos , Camundongos , Fosforilcolina/farmacologia , Esfingosina/farmacologia
17.
J Leukoc Biol ; 104(3): 615-630, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29656400

RESUMO

Neutrophils are important mediators of the innate immune defense and of the host response to a physical trauma. Because aberrant infiltration of injured sites by neutrophils was shown to cause adverse effects after trauma, we investigated how neutrophil infiltration could be modulated at the cellular level. Our data indicate that protein kinase D (PKD) is a vital regulator of neutrophil transmigration. PKD phosphorylates the Cofilin-phosphatase Slingshot-2L (SSH-2L). SSH-2L in turn dynamically regulates Cofilin activity and actin polymerization in response to a chemotactic stimulus for neutrophils, for example, fMLP. Here, we show that inhibition of PKD by two specific small molecule inhibitors results in broad, unrestricted activation of Cofilin and strongly increases the F-actin content of neutrophils even under basal conditions. This phenotype correlates with a significantly impaired neutrophil deformability as determined by optical stretcher analysis. Consequently, inhibition of PKD impaired chemotaxis as shown by reduced extravasation of neutrophils. Consequently, we demonstrate that transendothelial passage of both, neutrophil-like NB4 cells and primary PMNs recovered from a hemorrhagic shock trauma model was significantly reduced. Thus, inhibition of PKD may represent a promising modulator of the neutrophil response to trauma.


Assuntos
Actinas/metabolismo , Infiltração de Neutrófilos/imunologia , Proteína Quinase C/metabolismo , Choque Hemorrágico/imunologia , Migração Transendotelial e Transepitelial/imunologia , Animais , Linhagem Celular , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Polimerização , Proteína Quinase C/imunologia , Transdução de Sinais/imunologia , Suínos
18.
J Clin Invest ; 127(7): 2842-2854, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28581443

RESUMO

The quantity and activation state of adipose tissue macrophages (ATMs) impact the development of obesity-induced metabolic diseases. Appetite-controlling hormones play key roles in obesity; however, our understanding of their effects on ATMs is limited. Here, we have shown that human and mouse ATMs express NPFFR2, a receptor for the appetite-reducing neuropeptide FF (NPFF), and that NPFFR2 expression is upregulated by IL-4, an M2-polarizing cytokine. Plasma levels of NPFF decreased in obese patients and high-fat diet-fed mice and increased following caloric restriction. NPFF promoted M2 activation and increased the proliferation of murine and human ATMs. Both M2 activation and increased ATM proliferation were abolished in NPFFR2-deficient ATMs. Mechanistically, the effects of NPFF involved the suppression of E3 ubiquitin ligase RNF128 expression, resulting in enhanced stability of phosphorylated STAT6 and increased transcription of the M2 macrophage-associated genes IL-4 receptor α (Il4ra), arginase 1 (Arg1), IL-10 (Il10), and alkylglycerol monooxygenase (Agmo). NPFF induced ATM proliferation concomitantly with the increase in N-Myc downstream-regulated gene 2 (Ndrg2) expression and suppressed the transcription of Ifi200 cell-cycle inhibitor family members and MAF bZIP transcription factor B (Mafb), a negative regulator of macrophage proliferation. NPFF thus plays an important role in supporting healthy adipose tissue via the maintenance of metabolically beneficial ATMs.


Assuntos
Tecido Adiposo/imunologia , Proliferação de Células , Ativação de Macrófagos , Macrófagos/imunologia , Oligopeptídeos/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Arginase/genética , Arginase/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Fator de Transcrição MafB/genética , Fator de Transcrição MafB/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Oligopeptídeos/genética , Proteínas/genética , Proteínas/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia
19.
Anticancer Res ; 35(10): 5587-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26408730

RESUMO

AIM: Adjuvant treatment is still controversially discussed for elderly colon cancer (CC) patients. Our aim was to investigate the benefit of adjuvant treatment for younger (<70 years) and elderly (≥70 years) patients. PATIENTS AND METHODS: The long-term outcome of patients (n=855) enrolled in a randomized controlled trial comparing adjuvant chemotherapy with 5-FU alone, 5-FU plus folinic acid (FA), and 5-FU plus interferon-alpha (IFNa) was compared in younger (<70 years) and elderly (≥70 years) patients using a quotient of each patient's survival time and his expected residual life expectancy (QSL) and a multivariate Cox proportional hazards model. RESULTS: Eight-year overall survival (OS) rates were 58.3% and 57.4% for younger (n=653) and elderly (n=202) patients, respectively. In elderly patients, 8-year OS rates were 51.4%, 61.8%, and 56.3, and median QSL scores were 0.338, 0.371, and 0.343 for 5-FU (n=59), 5-FU plus FA (n=76), and 5-FU plus IFNa (n=67), respectively. In elderly patients treatment with 5-FU plus FA decreased the risk for an event by 1.5-fold compared to 5-FU (HR=0.657, 95%CI=0.495-0.870, p=0.004) and 5-FU plus INFa (HR=0.685, 95%CI=0.515-0.912, p=0.009). CONCLUSION: Our analysis clearly demonstrates for the first time an additional benefit of FA for adjuvant treatment of elderly CC patients. We conclude that this regimen is very safe and effective for adjuvant treatment of elderly patients.


Assuntos
Adenocarcinoma/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/mortalidade , Recidiva Local de Neoplasia/mortalidade , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Interferon-alfa/administração & dosagem , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Adulto Jovem
20.
Artigo em Inglês | MEDLINE | ID: mdl-26504700

RESUMO

Spigelian hernia is a rare clinical entity and has a subtle clinical presentation with vague abdominal pain, which can cause an important delay in diagnosis. Given the relatively high risk of incarceration the diagnosis of Spigelian hernia is an indication for surgical repair. Laparoscopic Spigelian mesh herniorraphy has gained recognition as an effective tension-free method and is associated with lower recurrence. Appropriate fixation techniques are however required to reduce complications such as nerve irritation, hematoma, and postoperative chronic pain. In this case report we describe a novel approach in laparoscopic mesh repair of Spigelian hernia, securing a lightweight composite mesh with fibrin sealant. This fixation seems to be a reasonable, feasible alternative to the standard tissue-penetrating mesh fixation.

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