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1.
Nat Immunol ; 24(7): 1098-1109, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37337103

RESUMO

Macrophages are involved in immune defense, organogenesis and tissue homeostasis. Macrophages contribute to the different phases of mammary gland remodeling during development, pregnancy and involution postlactation. Less is known about the dynamics of mammary gland macrophages in the lactation stage. Here, we describe a macrophage population present during lactation in mice. By multiparameter flow cytometry and single-cell RNA sequencing, we identified a lactation-induced CD11c+CX3CR1+Dectin-1+ macrophage population (liMac) that was distinct from the two resident F4/80hi and F4/80lo macrophage subsets present pregestationally. LiMacs were predominantly monocyte-derived and expanded by proliferation in situ concomitant with nursing. LiMacs developed independently of IL-34, but required CSF-1 signaling and were partly microbiota-dependent. Locally, they resided adjacent to the basal cells of the alveoli and extravasated into the milk. We found several macrophage subsets in human milk that resembled liMacs. Collectively, these findings reveal the emergence of unique macrophages in the mammary gland and milk during lactation.


Assuntos
Lactação , Leite Humano , Gravidez , Feminino , Camundongos , Humanos , Animais , Macrófagos , Glândulas Mamárias Animais
2.
Langenbecks Arch Surg ; 409(1): 111, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587539

RESUMO

PURPOSE: The presence of an aberrant right hepatic artery (aRHA), arising from the superior mesenteric artery, is a common variant of the liver vascular anatomy. Considering that tumor spread occurs along vessels, the question arises, whether the presence of an aRHA influences the oncologic outcome after resection for cancer of the pancreatic head. METHODS: Patients with ductal adenocarcinoma of the pancreatic head, who underwent resection from 2011 to 2020 at the Frankfurt University Hospital, Germany, were analyzed retrospectively. Surgical records and computed tomography imaging were reviewed for the presence of aRHA. Overall and disease-free survival as well as hepatic recurrence were analyzed according to the presence of aRHA. RESULTS: aRHA was detected in 21 out of 145 patients (14.5%). The median overall survival was 26 months (95%CI 20.8-34.4), median disease-free survival was 12.1 months (95%CI 8.1-17.3). There was no significant difference in overall survival (26.1 versus 21.4 months, adjusted hazard ratio 1.31, 95%CI 0.7-2.46, p = 0.401) or disease-free survival (14.5 months versus 12 months, adjusted hazard ratio 0.98, 95%CI 0.57-1.71, p = 0.957) without and with aRHA. The hepatic recurrence rate was 24.4.% with conventional anatomy versus 30.8% with aRHA (adjusted odds ratio 1.36, 95%CI 0.3-5.38, p = 0.669). In the multivariable analysis, only lymphatic vessel invasion was an independent prognostic factor for hepatic recurrence. CONCLUSIONS: The presence of an aRHA does not seem to influence the long-term survival and hepatic recurrence after resection for ductal adenocarcinoma of the pancreatic head.


Assuntos
Adenocarcinoma , Artéria Hepática , Humanos , Artéria Hepática/cirurgia , Estudos Retrospectivos , Pâncreas , Pancreatectomia
3.
Magn Reson Chem ; 61(6): 345-355, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36840535

RESUMO

We studied the micellar and solubilizing properties of aqueous solutions of unfractionated rhamnolipids produced by Pseudomonas aeruginosa. We used nuclear magnetic resonance (NMR) diffusometry, dynamic light scattering, and conductometry to measure the critical micelle concentration (CMC) of rhamnolipid solutions and determined the effective hydrodynamic radii of rhamnolipid monomers and micelles. Based on selective measurements of the self-diffusion coefficients of molecules, performed by NMR diffusometry, the solubilizing properties of rhamnolipids were studied depending on their concentration in solution; aromatic hydrocarbons, benzene, toluene, ethylbenzene, and para-xylene were taken as solubilizates. On the basis of the measurement results, we estimated the distribution coefficient of the solubilizate between the micellar (solubilized) and free (in the aqueous phase) states and the solubilizing capacity of rhamnolipid micelles.

4.
Eur J Immunol ; 51(7): 1799-1808, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33759186

RESUMO

Mononuclear phagocytes consisting of monocytes, macrophages, and DCs play a complex role in tumor development by either promoting or restricting tumor growth. Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer arising from transformed epidermal keratinocytes. While present at high numbers, the role of tumor-infiltrating and resident myeloid cells in the formation of cSCC is largely unknown. Using transgenic mice and depleting antibodies to eliminate specific myeloid cell types in the skin, we investigated the involvement of mononuclear phagocytes in the development of UV-induced cSCC in K14-HPV8-E6 transgenic mice. Although resident Langerhans cells were enriched in the tumor, their contribution to tumor formation was negligible. Equally, dermal macrophages were dispensable for the development of cSCC. In contrast, mice lacking circulating monocytes were completely resistant to UV-induced cSCC, indicating that monocytes promote tumor development. Collectively, these results demonstrate a critical role for classical monocytes in the initiation of skin cancer.


Assuntos
Carcinogênese/patologia , Epiderme/patologia , Monócitos/patologia , Neoplasias Cutâneas/patologia , Raios Ultravioleta/efeitos adversos , Animais , Carcinogênese/efeitos da radiação , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Epiderme/efeitos da radiação , Feminino , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/efeitos da radiação , Pele/patologia , Pele/efeitos da radiação
5.
Zentralbl Chir ; 147(5): 492-502, 2022 Oct.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-33045755

RESUMO

INTRODUCTION: In view of the limited capacities in intensive care units and the increasing economic burden, identification of risk factors could allow better and more efficient planning. Therefore, the aim of this study was to assess independent risk factors for the duration of intensive care unit stay after pancreatoduodenectomy (PD). METHODS: 147 patients who underwent pancreatoduodenectomy in the time period from 2013 to 2015 were identified from a prospective database and a retrospective analysis was performed. The primary endpoint was length of time spent in the ICU. A retrograde analysis was performed using univariate and multivariate regression analysis. All pre-, intra- and postoperative parameters were considered in the analysis. RESULTS: The median time spent in the intensive care unit (ICU) is one day. The univariate analysis demonstrated increased pack years, cerebrovascular events, anticoagulation, elevated creatinine and CA 19-9 as preoperative risk factors. In multivariate analysis, antihypertensive medication (AHT; OR 2.46; 95% CI 1.57 - 3.87; p = 0.05), operation time (OR 1.01; 95% CI 1.00 - 1.01; p = 0.03), extended LAD (OR 5.46; 95% CI 2.77 - 10.75; p = 0.01) and severe PPH (OR 4.01; 95% CI 2.07 - 7.76; p = 0.04) are significant risk factors for longer ICU stay. DISCUSSION: Patients with cardiovascular risk factors and elevated preoperative creatinine level are at greater risk for a prolonged ICU stay. Risk and benefit of an extended LAD should be weighed during the operation. Median duration on ICU/IMC after PD is one day or less for patients without risk factors. Whether routine monitoring in the ICU/IMC after PD is necessary must be clarified in further studies.


Assuntos
Anti-Hipertensivos , Pancreaticoduodenectomia , Anticoagulantes , Creatinina , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Pancreaticoduodenectomia/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
6.
Nat Chem Biol ; 15(5): 540-548, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30911179

RESUMO

Cell-based biosensors have great potential to detect various toxic and pathogenic contaminants in aqueous environments. However, frequently they cannot meet practical requirements due to insufficient sensing performance. To address this issue, we investigated a modular, cascaded signal amplifying methodology. We first tuned intracellular sensory receptor densities to increase sensitivity, and then engineered multi-layered transcriptional amplifiers to sequentially boost output expression level. We demonstrated these strategies by engineering ultrasensitive bacterial sensors for arsenic and mercury, and improved detection limit and output up to 5,000-fold and 750-fold, respectively. Coupled by leakage regulation approaches, we developed an encapsulated microbial sensor cell array for low-cost, portable and precise field monitoring, where the analyte can be readily quantified via displaying an easy-to-interpret volume bar-like pattern. The ultrasensitive signal amplifying methodology along with the background regulation and the sensing platform will be widely applicable to many other cell-based sensors, paving the way for their real-world applications.


Assuntos
Arsênio/análise , Técnicas Biossensoriais , Telefone Celular , Metais Pesados/análise , Técnicas Analíticas Microfluídicas , Arsênio/efeitos adversos , Técnicas Biossensoriais/instrumentação , Telefone Celular/instrumentação , Humanos , Metais Pesados/efeitos adversos , Técnicas Analíticas Microfluídicas/instrumentação
7.
Pancreatology ; 21(5): 957-964, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33775565

RESUMO

BACKGROUND: Postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) can be associated with severe postoperative morbidity. This study aims to develop a preoperative POPF risk calculator that can be easily implemented in clinical routine. METHODS: Patients undergoing PD were identified from a prospectively-maintained database. A total of 11 preoperative baseline and CT-based radiological parameters were used in a binominal logistic regression model. Parameters remaining predictive for grade B/C POPF were entered into the risk calculator and diagnostic accuracy measures and ROC curves were calculated for a training and a test patient cohort. The risk calculator was transformed into a simple nomogram. RESULTS: A total of 242 patients undergoing PD in the period from 2012 to 2018 were included. CT-imaging-based maximum main pancreatic duct (MPD) diameter (p = 0.047), CT-imaging-based pancreatic gland diameter at the anticipated resection margin (p = 0.002) and gender (p = 0.058) were the parameters most predictive for grade B/C POPF. Based on these parameters, a risk calculator was developed to identify patients at high risk of developing grade B/C POPF. In a training cohort of PD patients this risk calculator was associated with an AUC of 0.808 (95%CI 0.726-0.874) and an AUC of 0.756 (95%CI 0.669-0-830) in the independent test cohort. A nomogram applicable as a visual risk scale for quick assessment of POPF grade B/C risk was developed. CONCLUSION: The preoperative POPF risk calculator provides a simple tool to stratify patients planned for PD according to the risk of developing postoperative grade B/C POPF. The nomogram visual risk scale can be easily integrated into clinical routine and may be a valuable model to select patients for POPF-preventive therapy or as a stratification tool for clinical trials.


Assuntos
Fístula Pancreática , Pancreaticoduodenectomia , Humanos , Pâncreas/cirurgia , Ductos Pancreáticos/cirurgia , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
8.
Pancreatology ; 21(1): 155-162, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33309623

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal malignancy characterized by early loco-regional invasion. Portal vein resection (PVR) during pancreatoduodenectomy (PD) for PDAC is performed if tumor cell invasion to the venous wall (PVI) is suspected. The aim of this study is to evaluate radiological criteria for predicting PVR and PVI. METHODS: Patients undergoing PD for PDAC were identified from a prospectively maintained database. On the basis of CT- and MRI-based imaging portal vein tumor contact (PV), stranding of the superior mesenteric artery (SMA) and any alterations of the superior mesenterico-portal vein (SMPV) were evaluated. The accuracy of PVI and PVR prediction based on the radiological parameters was calculated. RESULTS: 143 patients were included in the study. 48 patients underwent PVR (34%), PVI was diagnosed in 23 patients (16%). Median overall survival was 22 months. Prediction of PVR (sensitivity 79%, negative predictive value 88%, p = 0.010) and PVI (sensitivity 95%, negative predictive value 99%, p = 0.002) was most accurate for any SMPV alterations as compared to the other radiological parameters. SMPV alterations qualified as an independent prognostic parameter (26.5 months vs. 33.5months, p = 0.034). CONCLUSION: Radiological evaluation of any SMPV alterations is a simple preoperative method to accurately predict PVI. Assessing SMPV alterations may help to identify candidates for neoadjuvant therapy.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Veias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Veia Porta/cirurgia , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida , Tomografia Computadorizada por Raios X
9.
Pancreatology ; 20(3): 433-441, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31987649

RESUMO

BACKGROUND/OBJECTIVE: The benefit of adjuvant therapy in ampullary cancer (AMPAC) patients following pancreatoduodenectomy (PD) is debated. The aim of this study was to determine the role of adjuvant therapy after pancreatoduodenectomy (PD) in histological subtypes of AMPAC. METHODS: Patients undergoing PD for AMPAC at 5 high-volume European surgical centers from 1996 to 2017 were identified. Patient baseline characteristics, surgical and histopathological parameters, and long-term overall survival (OS) after resection were evaluated. RESULTS: 214 patients undergoing PD for AMPAC were included. ASA score (ASA1-2 149 vs. ASA 3-4 82 months median OS, p = 0.002), preoperative serum CEA (CEA <0.5 ng/ml 128 vs. CEA >0.5 ng/ml 62 months, p = 0.013), preoperative serum CA19-9 (CA19-9 < 40 IU/ml 147 vs. CA19-9 > 40IU/ml 111 months, p = 0.042), T stage (T1-2 163 vs. T3-4 98 months, p < 0.001), N stage (N0 159 vs. N+ 110 months, p < 0.001), grading (G1-2 145 vs. G3-4 113 months, p = 0.026), R status (R0 136 vs. R+ 38 months, p = 0.031), and histological subtype (intestinal subtype 156 vs. PB/M subtype 118 months, p = 0.003) qualified as prognostic parameters. In multivariable analysis, ASA score (HR 1.784, 95%CI 0.997-3.193, p = 0.050) and N stage (HR 1.831, 95%CI 0.904-3.707, p = 0.033) remained independent prognostic factors. In PB/M subtype AMPAC, patients undergoing adjuvant therapy showed an improved median overall survival (adjuvant therapy 85 months vs. no adjuvant therapy 65 months, p = 0.005), and adjuvant therapy remained an independent prognostic parameter in multivariate analysis (HR 0.351, 95%CI 0.151-0.851, p = 0.015). There was no significant benefit of adjuvant therapy in intestinal subtype AMPAC patients. CONCLUSION: Adjuvant treatment seems indicated in pancreatobiliary or mixed type AMPAC.


Assuntos
Adenocarcinoma/terapia , Neoplasias do Sistema Biliar/terapia , Quimiorradioterapia Adjuvante/métodos , Neoplasias Pancreáticas/terapia , Pancreaticoduodenectomia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampola Hepatopancreática/patologia , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/cirurgia , Biomarcadores , Quimioterapia Adjuvante , Estudos de Coortes , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Prognóstico , Análise de Sobrevida
10.
Pancreatology ; 19(7): 985-993, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31563328

RESUMO

BACKGROUND/OBJECTIVE: The impact of preoperative biliary stenting (PBS) before pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) is controversial. METHODS: Patients undergoing PD with or without PBS for PDAC were identified from the German DGAV-StuDoQlPancreas registry. The impact of PBS on perioperative complications was analyzed. RESULTS: 1133 patients undergoing PD for PDAC were identified from the registry. After matching, 480 PBS patients vs. 480 patients without PBS were analyzed. Postoperative complications Clavien-Dindo classification (CDC) grade IIIa-IVb were higher in PBS patients (PBS 27% vs. no PBS 22%, p = 0.027). 320 PBS patients (66%) had no history of jaundice. In these patients, PBS was associated with higher morbidity. In contrast, PBS was not associated with higher complication rates in patients with history of jaundice. Serum bilirubin levels of 15 mg/dl and higher lead to more CDC IIIa-IVb (24% vs. 28%, p = 0.053) and higher mortality (3% vs. 7%, p < 0.001). PBS in patients with serum bilirubin levels of >15 mg/dl increased CDC IIa-IVb complications (21% vs. 50%, p = 0.001), mortality was equivalent. CONCLUSION: Most PBS procedures were performed in patients with no history of jaundice and increased morbidity. Serum bilirubin levels >15 mg/dl lead to higher morbidity and mortality. PBS correlated with higher complication rates in these patients.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Sistema de Registros , Stents , Idoso , Estudos de Casos e Controles , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Razão de Chances , Complicações Pós-Operatórias , Cuidados Pré-Operatórios
11.
Pancreatology ; 19(1): 17-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30563791

RESUMO

BACKGROUND: Postoperative pancreatic fistula (POPF) is a major factor for morbidity and mortality after pancreatic resection. Risk stratification for POPF is important for adjustment of treatment, selection of target groups in trials and quality assessment in pancreatic surgery. In this study, we built a risk-prediction model for POPF based on a large number of predictor variables from the German pancreatic surgery registry StuDoQ|Pancreas. METHODS: StuDoQ|Pancreas was searched for patients, who underwent pancreatoduodenectomy from 2014 to 2016. A multivariable logistic regression model with elastic net regularization was built including 66 preoperative und intraoperative parameters. Cross-validation was used to select the optimal model. The model was assessed via area under the ROC curve (AUC) and calibration slope and intercept. RESULTS: A total of N = 2488 patients were included. In the optimal model the predictors selected were texture of the pancreatic parenchyma (soft versus hard), body mass index, histological diagnosis pancreatic ductal adenocarcinoma and operation time. The AUC was 0.70 (95% CI 0.69-0.70), the calibration slope 1.67 and intercept 1.12. In the validation set the AUC was 0.65 (95% CI 0.64-0.66), calibration slope and intercept were 1.22 and 0.42, respectively. CONCLUSION: The model we present is a valid measurement instrument for POPF risk based on four predictor variables. It can be applied in clinical practice as well as for risk-adjustment in research studies and quality assurance in surgery.


Assuntos
Pancreatopatias/complicações , Pancreatopatias/cirurgia , Fístula Pancreática/etiologia , Complicações Pós-Operatórias , Feminino , Alemanha , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Pancreatopatias/patologia , Fístula Pancreática/patologia , Sistema de Registros , Fatores de Risco
12.
HPB (Oxford) ; 21(11): 1513-1519, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30956162

RESUMO

BACKGROUND: Distal cholangiocarcinoma (DCC) is a rare malignancy and validated prognostic markers remain scarce. We aimed to evaluate the role of serum CA19-9 as a potential biomarker in DCC. METHODS: Patients operated for DCC at 6 high-volume surgical centers from 1994 to 2015 were identified from prospectively maintained databases. Patient baseline characteristics, surgical and histopathological parameters, as well as overall survival after resection were assessed for correlation with preoperative bilirubin-adjusted serum carbohydrate antigen 19-9 (CA19-9). Preoperative CA19-9 to bilirubin ratio (CA19-9/BR) was classified as elevated (≥ 25 U/ml/mg/dl) according to the upper serum normal values of CA19-9 (37 U/ml) and bilirubin (1.5 mg/dl) giving a cut-off at ≥ 25 U/ml/mg/dl. RESULTS: In total 179 patients underwent resection for DCC during the study period. High preoperative CA19-9/BR was associated with advanced age and regional lymph node metastases. Median overall survival after resection was 27 months. Elevated preoperative serum CA19-9/bilirubin ratio (HR 1.6, p = 0.025), T3/4 stage (HR 1.8, p = 0.022), distant metastasis (HR 2.5, p = 0.007), tumor grade (HR 1.9, p = 0.001) and R status (HR 1.7, p = 0.023) were identified as independent negative prognostic factors following multivariable analysis. CONCLUSION: Elevated preoperative bilirubin-adjusted serum CA19-9 correlates with regional lymph node metastases and constitutes a negative independent prognostic factor after resection of DCC.


Assuntos
Bilirrubina/sangue , Antígeno CA-19-9/sangue , Colangiocarcinoma/sangue , Colangiocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
13.
Nucleic Acids Res ; 44(7): e68, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-26704969

RESUMO

The capability to rapidly design proteins with novel functions will have a significant impact on medicine, biotechnology and synthetic biology. Synthetic genes are becoming a commodity, but integrated approaches have yet to be developed that take full advantage of gene synthesis. We developed a solid-phase gene synthesis method based on asymmetric primer extension (APE) and coupled this process directly to high-throughput, on-chip protein expression, purification and characterization (via mechanically induced trapping of molecular interactions, MITOMI). By completely circumventing molecular cloning and cell-based steps, APE-MITOMI reduces the time between protein design and quantitative characterization to 3-4 days. With APE-MITOMI we synthesized and characterized over 400 zinc-finger (ZF) transcription factors (TF), showing that although ZF TFs can be readily engineered to recognize a particular DNA sequence, engineering the precise binding energy landscape remains challenging. We also found that it is possible to engineer ZF-DNA affinity precisely and independently of sequence specificity and that in silico modeling can explain some of the observed affinity differences. APE-MITOMI is a generic approach that should facilitate fundamental studies in protein biophysics, and protein design/engineering.


Assuntos
Genes Sintéticos , Dispositivos Lab-On-A-Chip , Engenharia de Proteínas/métodos , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Nat Methods ; 11(8): 841-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24997862

RESUMO

The spatial organization of membrane-bound ligands is thought to regulate receptor-mediated signaling. However, direct regulation of receptor function by nanoscale distribution of ligands has not yet been demonstrated, to our knowledge. We developed rationally designed DNA origami nanostructures modified with ligands at well-defined positions. Using these 'nanocalipers' to present ephrin ligands, we showed that the nanoscale spacing of ephrin-A5 directs the levels of EphA2 receptor activation in human breast cancer cells. Furthermore, we found that the nanoscale distribution of ephrin-A5 regulates the invasive properties of breast cancer cells. Our ligand nanocaliper approach has the potential to provide insight into the roles of ligand nanoscale spatial distribution in membrane receptor-mediated signaling.


Assuntos
Nanotecnologia , Receptores de Superfície Celular/metabolismo , Endocitose , Ligantes
15.
Langenbecks Arch Surg ; 402(5): 831-840, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28612115

RESUMO

PURPOSE: Pancreatoduodenectomy is the most common operative procedure performed for distal bile duct carcinoma. Data on outcome after surgery for this rare malignancy is scarce, especially from western countries. The purpose of this study is to explore the prognostic factors and outcome after pancreatoduodenectomy for distal bile duct carcinoma. METHODS: Patients receiving pancreatoduodenectomy for distal bile duct carcinoma were identified from institutional databases of five German and one Russian academic centers for pancreatic surgery. Univariable and multivariable general linear model, Kaplan-Meier method, and Cox regression were used to identify prognostic factors for postoperative mortality and overall survival. RESULTS: N = 228 patients operated from 1994 to 2015 were included. Reoperation (OR 5.38, 95%CI 1.51-19.22, p = 0.010), grade B/C postpancreatectomy hemorrhage (OR 3.73, 95%CI 1.13-12.35, p = 0.031), grade B/C postoperative pancreatic fistula (OR 4.29, 95%CI 1.25-14.72, p = 0.038), and advanced age (OR 4.00, 95%CI 1.12-14.03, p = 0.033) were independent risk factors for in-hospital mortality in multivariable analysis. Median survival was 29 months, 5-year survival 27%. Positive resection margin (HR 2.07, 95%CI 1.29-3.33, p = 0.003), high tumor grade (HR 1.71, 95%CI 1.13-2.58, p = 0.010), lymph node (HR 1.68, 95%CI 1.13-2.51, p = 0.011), and distant metastases (HR 2.70, 95%CI 1.21-5.58, p = 0.014), as well as severe non-fatal postoperative complications (HR 1.64, 95%CI 1.04-2.58, p = 0.033) were independent negative prognostic factors for survival in multivariable analysis. CONCLUSION: Distant metastases and positive resection margin are the strongest negative prognostic factors for survival after pancreatoduodenectomy for distal bile duct carcinoma; thus, surgery with curative intent is only warranted in patients with local disease, where R0 resection is feasible.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Pancreaticoduodenectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Prognóstico , Reoperação , Estudos Retrospectivos , Federação Russa , Taxa de Sobrevida , Resultado do Tratamento
16.
J Pediatr Orthop ; 37 Suppl 1: S16-S23, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28594688

RESUMO

Lower extremity deformities of patients with arthrogryposis multiplex congenita present a wide spectrum of severity and deformity combinations. Treatment goals range from merely ensuring comfortable seating and shoe wear, to fully independent and active ambulation, but the overarching intention is to help realize the patient's greatest potential for independence and function. Treatment of hip and knee contractures and dislocations has become more interventional, whereas treatment of foot deformities has paradoxically become much less surgical. This article synopsizes the treatment strategies presented in September 2014 in Saint Petersburg, Russia at the second international symposium on arthrogryposis.


Assuntos
Artrogripose/cirurgia , Artroplastia/métodos , Contratura/cirurgia , Músculo Esquelético/cirurgia , Pré-Escolar , Pé Torto Equinovaro/cirurgia , Feminino , Contratura de Quadril/cirurgia , Articulação do Quadril/anormalidades , Articulação do Quadril/cirurgia , Humanos , Lactente , Luxações Articulares/cirurgia , Articulação do Joelho/anormalidades , Articulação do Joelho/cirurgia , Masculino , Síndrome
17.
Nano Lett ; 16(12): 7882-7890, 2016 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960483

RESUMO

Through the use of optical tweezers we performed controlled translocations of DNA-protein complexes through nanocapillaries. We used RNA polymerase (RNAP) with two binding sites on a 7.2 kbp DNA fragment and a dCas9 protein tailored to have five binding sites on λ-DNA (48.5 kbp). Measured localization of binding sites showed a shift from the expected positions on the DNA that we explained using both analytical fitting and a stochastic model. From the measured force versus stage curves we extracted the nonequilibrium work done during the translocation of a DNA-protein complex and used it to obtain an estimate of the effective charge of the complex. In combination with conductivity measurements, we provided a proof of concept for discrimination between different DNA-protein complexes simultaneous to the localization of their binding sites.


Assuntos
Proteínas de Bactérias/análise , RNA Polimerases Dirigidas por DNA/análise , DNA/análise , Endonucleases/análise , Nanotubos , Pinças Ópticas , Sítios de Ligação , Proteína 9 Associada à CRISPR
18.
Surgery ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38789356

RESUMO

BACKGROUND: The method of transecting the pancreatic parenchyma during pancreatic resection may influence the rate of complications, including pancreatic fistula and bleeding. The objective of this study is to compare the transection of the pancreatic parenchyma during pancreatoduodenectomy with monopolar electrocautery versus scalpel in terms of postoperative complications. METHODS: A retrospective analysis of patients with open pancreatoduodenectomy from the German DGAV StuDoQ|Pancreas registry (January 2013 to December 2021) was performed. Transection of the pancreatic parenchyma with a scalpel versus monopolar electrocautery was compared regarding postoperative pancreatic fistula B/C, post-pancreatectomy hemorrhage B/C, and major complications (Clavien-Dindo classification ≥3) rates. Multivariable analysis with adjustment for potential confounders and surgical center cluster effect was performed. RESULTS: Overall, 6,752 patients were included in the study. In 4,072 (60.3%), transection was performed with a scalpel and, in 2,680 (39.7%), with electrocautery. Transection with electrocautery was associated with higher postoperative pancreatic fistula B/C (15.4% vs 12.8%; P = .003), post-pancreatectomy hemorrhage B/C (11% vs 7.4%; P < .001), and major complications (33.4% vs 29.6%; P = .001) rates. In the multivariable analysis, after adjustment for potential confounders and surgical center, the association of the transection method with postoperative pancreatic fistula B/C (odds ratio = 1.01; 95% CI, 0.79-1.2; P = .962), post-pancreatectomy hemorrhage B/C (odds ratio = 1.23; 95% CI, 0.94-1.6; P = .127), and major complications (odds ratio = 1.09; 95% CI, 0.93-1.27; P = .297) was not significant. CONCLUSION: The study found no significant association between transection of the pancreatic parenchyma during open pancreatoduodenectomy with a scalpel compared with monopolar electrocautery regarding pancreatic fistula, postoperative bleeding, or overall major complication rates.

19.
Nat Nanotechnol ; 19(2): 237-245, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37813939

RESUMO

Insulin binds the insulin receptor (IR) and regulates anabolic processes in target tissues. Impaired IR signalling is associated with multiple diseases, including diabetes, cancer and neurodegenerative disorders. IRs have been reported to form nanoclusters at the cell membrane in several cell types, even in the absence of insulin binding. Here we exploit the nanoscale spatial organization of the IR to achieve controlled multivalent receptor activation. To control insulin nanoscale spatial organization and valency, we developed rod-like insulin-DNA origami nanostructures carrying different numbers of insulin molecules with defined spacings. Increasing the insulin valency per nanostructure markedly extended the residence time of insulin-DNA origami nanostructures at the receptors. Both insulin valency and spacing affected the levels of IR activation in adipocytes. Moreover, the multivalent insulin design associated with the highest levels of IR activation also induced insulin-mediated transcriptional responses more effectively than the corresponding monovalent insulin nanostructures. In an in vivo zebrafish model of diabetes, treatment with multivalent-but not monovalent-insulin nanostructures elicited a reduction in glucose levels. Our results show that the control of insulin multivalency and spatial organization with nanoscale precision modulates the IR responses, independent of the insulin concentration. Therefore, we propose insulin nanoscale organization as a design parameter in developing new insulin therapies.


Assuntos
DNA , Nanoestruturas , Receptor de Insulina , Animais , Diabetes Mellitus/tratamento farmacológico , DNA/química , Insulina , Nanoestruturas/química , Receptor de Insulina/efeitos dos fármacos , Receptor de Insulina/metabolismo , Peixe-Zebra
20.
Cell Rep ; 43(7): 114395, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38941187

RESUMO

Macrophages play crucial roles in organ-specific functions and homeostasis. In the adrenal gland, macrophages closely associate with sinusoidal capillaries in the aldosterone-producing zona glomerulosa. We demonstrate that macrophages preserve capillary specialization and modulate aldosterone secretion. Using macrophage-specific deletion of VEGF-A, single-cell transcriptomics, and functional phenotyping, we found that the loss of VEGF-A depletes PLVAP+ fenestrated endothelial cells in the zona glomerulosa, leading to increased basement membrane collagen IV deposition and subendothelial fibrosis. This results in increased aldosterone secretion, called "haptosecretagogue" signaling. Human aldosterone-producing adenomas also show capillary rarefaction and basement membrane thickening. Mice with myeloid cell-specific VEGF-A deletion exhibit elevated serum aldosterone, hypokalemia, and hypertension, mimicking primary aldosteronism. These findings underscore macrophage-to-endothelial cell signaling as essential for endothelial cell specialization, adrenal gland function, and blood pressure regulation, with broader implications for other endocrine organs.

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