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1.
Langenbecks Arch Surg ; 408(1): 191, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37171640

RESUMEN

PURPOSE: The objective of this work was to uncover inequalities in access to liver transplantation in Bavaria, Germany. METHODS: For this purpose, the annual transplantation rate per 1 million inhabitants for the respective districts was determined from the aggregated postal codes of the place of residence of transplanted patients. The variables examined were proximity and travel time to the nearest transplant center, as well as the care category of the regional hospital. In addition, we assessed whether the head of gastroenterology at the regional hospital through which liver transplant candidates are referred was trained at a liver transplant center. RESULTS: We could not demonstrate a direct relationship between proximity or travel time to the nearest transplant center and access to liver transplantation. Multivariate regression analysis shows that liver transplant training (p < 0.0001) of the chief physician (gastroenterologist) of the regional hospital was the most decisive independent factor for access to liver transplantation within a district. CONCLUSION: We show that the transplant training experience of the head of gastroenterology at a regional hospital is an independent factor for the regional transplantation rate. Therefore, it appears important to maintain some liver transplant expertise outside the transplant centers in order to properly identify and assign potential transplant candidates for transplantation.


Asunto(s)
Trasplante de Hígado , Médicos , Humanos , Alemania
2.
Z Gastroenterol ; 61(1): 71-75, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36379463

RESUMEN

Immunotherapy has become the standard of care in advanced HCC but is only approved in first- or second-line treatment. We report a patient with HCC refractory to several lines of tyrosine kinase inhibitors, who was treated with Ipilimumab and Nivolumab (Ipi/Nivo) as the fourth line. The tumor responded profoundly to Ipi/Nivo. Established biomarker-predicting responses to immunotherapy, such as a high PD-L1 staining, a high combined-positive score, microsatellite instability or a high tumor mutational burden, were not detected. Potential negative predictive markers for response to immunotherapy such as CTNNB1 and TERT were present. This constellation puts the spotlight on two mutations observed here in the SET domain-containing 2 (SETD2) and low-density lipoprotein receptor-related protein 1b (LRP1B) genes, which may explain the outstanding response. Our case demonstrates that immunotherapy can be efficient in a late-line scenario, resulting in long-term survival. Further studies should prospectively evaluate the value of SETD2 and LRP1B alterations as predictors for the success of immunotherapy in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Antígeno CTLA-4/genética , Ipilimumab , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Mutación , Nivolumab/uso terapéutico , Receptor de Muerte Celular Programada 1 , Receptores de LDL
3.
Ann Surg Oncol ; 29(13): 8523-8533, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36094690

RESUMEN

BACKGROUND: Pancreatic adenocarcinoma (PDAC) patients with preoperative carbohydrate antigen 19-9 (CA19-9) serum levels higher than 500 U/ml are classified as biologically borderline resectable (BR-B). To date, the impact of cholestasis on preoperative CA19-9 serum levels in these patients has remained unquantified. METHODS: Data on 3079 oncologic pancreatic resections due to PDAC that were prospectively acquired by the German Study, Documentation and Quality (StuDoQ) registry were analyzed in relation to preoperative CA19-9 and bilirubin serum values. Preoperative CA19-9 values were adjusted according to the results of a multivariable linear regression analysis of pathologic parameters, bilirubin, and CA19-9 values. RESULTS: Of 1703 PDAC patients with tumor located in the pancreatic head, 420 (24.5 %) presented with a preoperative CA19-9 level higher than 500 U/ml. Although receiver operating characteristics (ROC) analysis failed to determine exact CA19-9 cut-off values for prognostic indicators (R and N status), the T, N, and G status; the UICC stage; and the number of simultaneous vein resections increased with the level of preoperative CA19-9, independently of concurrent cholestasis. After adjustment of preoperative CA19-9 values, 18.5 % of patients initially staged as BR-B showed CA19-9 values below 500 U/ml. However, the postoperative pathologic results for these patients did not change compared with the patients who had CA19-9 levels higher than 500 U/ml after bilirubin adjustment. CONCLUSIONS: In this multicenter dataset of PDAC patients, elevation of preoperative CA19-9 correlated with well-defined prognostic pathologic parameters. Bilirubin adjustment of CA19-9 is feasible but does not affect the prognostic value of CA19-9 in jaundiced patients.


Asunto(s)
Adenocarcinoma , Carcinoma Ductal Pancreático , Colestasis , Neoplasias Pancreáticas , Humanos , Antígeno CA-19-9 , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/cirugía , Pronóstico , Adenocarcinoma/complicaciones , Adenocarcinoma/cirugía , Bilirrubina , Carcinoma Ductal Pancreático/complicaciones , Carcinoma Ductal Pancreático/cirugía , Estudios Retrospectivos , Biomarcadores de Tumor , Neoplasias Pancreáticas
6.
Z Gastroenterol ; 60(2): 184-191, 2022 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-34670296

RESUMEN

BACKGROUND: Multiple systemic therapy options have been recently approved for the treatment of hepatocellular carcinoma (HCC). In particular, immuno-oncology combination therapies can now achieve impressive response rates and significantly prolonged survival with good tolerability. These immuno-oncology (IO)-based combinations are currently not only evaluated for the therapy of advanced HCC, but increasingly also in earlier stages in terms of peri-interventional therapy concepts and also for down-sizing to local therapies. In the context of liver transplantation (LTx), a particularly critical benefit/risk assessment must be made before the use of immunotherapeutics in the context of multimodal concepts, since the risk of a potentially lethal rejection can be significantly increased by immunotherapy. METHODS: This review is based on a selective literature search performed between December 2020 and April 2021 in the PubMed and Cochrane Library databases. Guidelines, expert opinions, and recommendations from professional societies were given special consideration. RESULTS: Nearly one in five LTx in Germany are performed due to HCCs. In this context, LTx is a curative therapy option not only for the underlying liver disease but also for the malignant tumor. Individual case reports indicate that IO therapy prior to LTx may increase the risk of rejection or liver failure after subsequent liver transplantation. Since 2015, immunotherapeutics have also been widely used for tumor therapy in patients after LTx. In small case series, rejection rates of 36%, associated with rejection-related mortality of 20% of treated patients, have been described. A similar incidence of rejection has also been described following the use of immunotherapeutics in patients after other organ transplantations. CONCLUSION: In the context of organ transplantation, IO therapy carries the risk of graft rejection, which can lead to graft loss and also patient death. However, from today's point of view, IO-based therapy can be considered in the context of organ transplantation with a careful benefit/risk assessment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Carcinoma Hepatocelular/terapia , Humanos , Inmunoterapia , Neoplasias Hepáticas/terapia , Medición de Riesgo
7.
Immunobiology ; 226(6): 152144, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34624625

RESUMEN

Regulatory T cells (Tregs) maintain immune homeostasis by regulating the activation of other immune cells. Preclinical studies show that the infusion of Tregs can promote immunological tolerance to allografts and prevent or cure multiple autoimmune diseases. However, Treg therapy is limited by high numbers of cells required to induce tolerance. In this study, we aimed at improving the in vitro expansion of sort purified mouse Tregs using the CD28 Superagonist (CD28-SA) D665 and comparing it to the conventional expansion using anti-CD3/anti-CD28 Dynabeads®. CD28-SA-stimulated Tregs expanded more than Dynabead®-stimulated Tregs while maintaining their phenotype by expressing the same level of CD4, CD25 and Foxp3. CD28-SA-expanded Tregs produced comparable amounts of IL-10 and TGFß while showing a slightly superior suppressive capacity compared to Dynabead®-stimulated Tregs. Thus, stimulating murine Tregs with the CD28-SA is a promising alternative since it maintains their suppressive capacity without altering their phenotype and yields a higher fold expansion within 14 days.


Asunto(s)
Antígenos CD28/agonistas , Factores Inmunológicos/farmacología , Inmunomodulación/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Biomarcadores , Inmunofenotipificación , Activación de Linfocitos , Masculino , Ratones
8.
Langenbecks Arch Surg ; 406(7): 2479-2487, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34142218

RESUMEN

PURPOSE: Traditionally, previous wound infection was considered a contraindication to secondary skin closure; however, several case reports describe successful secondary wound closure of wounds "preconditioned" with negative pressure wound therapy (NPWT). Although this has been increasingly applied in daily practice, a systematic analysis of its feasibility has not been published thus far. The aim of this study was to evaluate secondary skin closure in previously infected abdominal wounds following treatment with NPWT. METHODS: Single-center retrospective analysis of patients with infected abdominal wounds treated with NPWT followed by either secondary skin closure referenced to a group receiving open wound therapy. Endpoints were wound closure rate, wound complications (such as recurrent infection or hernia), and perioperative data (such as duration of NPWT or hospitalization parameters). RESULTS: One hundred ninety-eight patients during 2013-2016 received a secondary skin closure after NPWT and were analyzed and referenced to 67 patients in the same period with open wound treatment after NPWT. No significant difference in BMI, chronic immunosuppressive medication, or tobacco use was found between both groups. The mean duration of hospital stay was 30 days with a comparable duration in both patient groups (29 versus 33 days, p = 0.35). Interestingly, only 7.7% of patients after secondary skin closure developed recurrent surgical site infection and in over 80% of patients were discharged with closed wounds requiring only minimal outpatient wound care. CONCLUSION: Surgical skin closure following NPWT of infected abdominal wounds is a good and safe alternative to open wound treatment. It prevents lengthy outpatient wound therapy and is expected to result in a higher quality of life for patients and reduce health care costs.


Asunto(s)
Terapia de Presión Negativa para Heridas , Humanos , Calidad de Vida , Estudios Retrospectivos , Infección de la Herida Quirúrgica/terapia , Cicatrización de Heridas
9.
Visc Med ; 37(2): 94-101, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33977098

RESUMEN

BACKGROUND: Liver resection is the most effective available therapy for patients with hepatocellular carcinoma (HCC). The accurate selection of patients for surgery requires determination of technical resectability and the risk of recurrence, as well as assessment of liver function and functional reserve to avoid postoperative liver failure. Previous studies have underlined the effectiveness and reliability of the LiMAx® test to evaluate liver function preoperatively. Nevertheless, data concerning HCC evaluation are lacking. METHODS: From 2014 to 2019, 92 patients with HCC underwent additional assessment of liver function using the LiMAx test prior to decision for or against liver resection. Preoperative LiMAx results were compared between cirrhotic and noncirrhotic liver. The clinical decision for surgery was evaluated applying the various liver function parameters available. RESULTS: Forty-six patients underwent liver resection. The LiMAx results were higher in resected patients (388 vs. 322 µg/kg/h; p = 0.004). LiMAx values were an independent risk factor for the presence of liver cirrhosis in multivariate analysis. In 17 patients, surgical treatment was cancelled due to major impairment of liver function. Only 4 out of 46 resected patients presented with post-hepatectomy liver failure (PHLF) grade ≥B. Histologic assessment revealed liver cirrhosis in 10 resected patients without PHLF. CONCLUSION: Preoperative determination of liver function by the LiMAx test enables effective and safe patient selection for HCC resection in both cirrhotic and noncirrhotic liver.

10.
BMC Cancer ; 21(1): 490, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33941104

RESUMEN

BACKGROUND: A prognostic benefit of additive chemotherapy in patients following resection of metachronous colorectal liver metastases (CRLM) remains controversial. Therefore, the goal of this retrospective study was to investigate the impact of perioperative chemotherapy on disease-free survival (DFS) and overall survival (OS) of patients after curative resection of metachronous CRLM. METHODS: In a retrospective single-centre study, patients after curative resection of metachronous CRLM were included and analysed for DFS and OS with regard to the administration of additive chemotherapy. The Kaplan-Meier method was applied to compare DFS and OS while Cox regression models were used to identify independent prognostic variables. RESULTS: Thirty-four of 75 patients were treated with additive 5-FU based chemotherapy. OS was significantly prolonged in this patient subgroup (62 vs 57 months; p = 0.032). Additive chemotherapy significantly improved 10-year survival rates (42% vs 0%, p = 0.023), but not 5-year survival (58% vs 42%, p = 0.24). Multivariate analysis identified additive chemotherapy (p = 0.016, HR 0.44, 95% CI 0.23-0.86), more than five CRLM (p = 0.026, HR 2.46, 95% CI 1.16-10.32) and disease recurrence (0.009, HR 2.70, 95% CI 1.29-5.65) as independent risk factors for OS. CONCLUSION: Additive chemotherapy significantly prolonged OS and 10-year survival in patients after curative resection of metachronous CRLM. Randomized clinical trials are needed in the future to identify optimal chemotherapy regimens for those patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Capecitabina/administración & dosificación , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Hepatectomía , Humanos , Estimación de Kaplan-Meier , Leucovorina/administración & dosificación , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo
11.
Lancet Gastroenterol Hepatol ; 6(2): 128-138, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33338442

RESUMEN

BACKGROUND: The optimal preoperative treatment for locally advanced pancreatic cancer is unknown. We aimed to compare the efficacy and safety of nab-paclitaxel plus gemcitabine with nab-paclitaxel plus gemcitabine followed by fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) as multidrug induction chemotherapy regimens in locally advanced pancreatic cancer. METHODS: In this open-label, multicentre, randomised phase 2 study, done at 28 centres in Germany, eligible patients were adults (aged 18-75 years) with an Eastern Cooperative Oncology Group performance status of 0 or 1 and histologically or cytologically confirmed, treatment-naive locally advanced pancreatic adenocarcinoma, as determined by local multidisciplinary team review. After two cycles of nab-paclitaxel 125 mg/m2 plus gemcitabine 1000 mg/m2 (administered intravenously on days 1, 8, and 15 of each 28-day cycle), patients without progressive disease or unacceptable adverse events were randomly assigned (1:1) to receive either two additional cycles of nab-paclitaxel plus gemcitabine (nab-paclitaxel plus gemcitabine group) or four cycles of sequential FOLFIRINOX (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, irinotecan 180 mg/m2, fluorouracil 400 mg/m2 by intravenous bolus followed by a continuous intravenous infusion of 2400 mg/m2 for 46 h on day 1 of each 14-day cycle; sequential FOLFIRINOX group). Randomisation was done by the clinical research organisation on request of the trial centre using a permuted block design (block size 2 and 4). Patients, investigators, and study team members were not masked to treatment allocation. The primary endpoint was surgical conversion rate (complete macroscopic tumour resection) in the randomised population by intention-to-treat analysis, which was assessed by surgical exploration in all patients with at least stable disease after completion of induction chemotherapy. This trial is registered with ClinicalTrials.gov, NCT02125136. FINDINGS: Between Nov 18, 2014, and April 27, 2018, 168 patients were registered and 130 were randomly assigned to either the nab-paclitaxel plus gemcitabine group (64 patients) or the sequential FOLFIRINOX group (66 patients). Surgical exploration after completed induction chemotherapy was done in 40 (63%) of 64 patients in the nab-paclitaxel plus gemcitabine group and 42 (64%) of 66 patients in the sequential FOLFIRINOX group. 23 patients in the nab-paclitaxel plus gemcitabine group and 29 in the sequential FOLFIRINOX group had complete macroscopic tumour resection, yielding a surgical conversion rate of 35·9% (95% CI 24·3-48·9) in the nab-paclitaxel plus gemcitabine group and 43·9% (31·7-56·7) in the sequential FOLFIRINOX group (odds ratio 0·72 [95% CI 0·35-1·45]; p=0·38). At a median follow-up of 24·9 months (95% CI 21·8-27·6), median overall survival was 18·5 months (95% CI 14·4-21·5) in the nab-paclitaxel plus gemcitabine group and 20·7 months (13·9-28·7) in the sequential FOLFIRINOX group (hazard ratio 0·86 [95% CI 0·55-1·36]; p=0·53). All other secondary efficacy endpoints, such as investigator-assessed progression-free survival, radiographic response rate, CA 19-9 response rate, and R0 resection rate, were not significantly different between the two treatment groups except for improved histopathological downstaging in evaluable resection specimens from the sequential FOLFIRINOX group (ypT1/2 stage: 20 [69%] of 29 patients in the sequential FOLFIRINOX group vs four [17%] of 23 patients in the nab-paclitaxel plus gemcitabine group, p=0·0003; ypN0 stage: 15 [52%] of 29 patients in the sequential FOLFIRINOX group vs four [17%] of 23 patients in the nab-paclitaxel plus gemcitabine group, p=0·02). Grade 3 or higher treatment-emergent adverse events during induction chemotherapy occurred in 35 (55%) of 64 patients in nab-paclitaxel plus gemcitabine group and in 35 (53%) of 66 patients in the sequential FOLFIRINOX group. The most common of which were neutropenia (18 [28%] in nab-paclitaxel plus gemcitabine group, 16 [24%] in the sequential FOLFIRINOX group), nausea and vomiting (two [3%] in nab-paclitaxel plus gemcitabine group, eight [12%] in the sequential FOLFIRINOX group), and bile duct obstruction with cholangitis (six [9%] in nab-paclitaxel plus gemcitabine group, seven [11%] in the sequential FOLFIRINOX group). No deaths were caused by treatment-related adverse events during the induction chemotherapy phase. INTERPRETATION: Our findings suggest that nab-paclitaxel plus gemcitabine is similarly active and safe as nab-paclitaxel plus gemcitabine followed by FOLFIRINOX as multidrug induction chemotherapy regimens for locally advanced pancreatic cancer. Although conversion to resectability was achieved in about a third of patients, additional evidence is required to determine whether this translates into improved overall survival. FUNDING: Celgene.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Albúminas/uso terapéutico , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Paclitaxel/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Desoxicitidina/uso terapéutico , Esquema de Medicación , Femenino , Fluorouracilo/uso terapéutico , Estudios de Seguimiento , Humanos , Quimioterapia de Inducción , Irinotecán/uso terapéutico , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Oxaliplatino/uso terapéutico , Pancreatectomía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Resultado del Tratamiento , Adulto Joven , Gemcitabina
12.
Ann Surg Oncol ; 28(4): 2325-2336, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32920720

RESUMEN

BACKGROUND: International consensus criteria (ICC) have redefined borderline resectability for pancreatic ductal adenocarcinoma (PDAC) according to three dimensions: anatomical (BR-A), biological (BR-B), and conditional (BR-C). The present definition acknowledges that resectability is not just about the anatomic relationship between the tumour and vessels but that biological and conditional dimensions also are important. METHODS: Patients' tumours were retrospectively defined borderline resectable according to ICC. The study cohort was grouped into either BR-A or BR-B and compared with patients considered primarily resectable (R). Differences in postoperative complications, pathological reports, overall (OS), and disease-free survival were assessed. RESULTS: A total of 345 patients underwent resection for PDAC. By applying ICC in routine preoperative assessment, 30 patients were classified as stage BR-A and 62 patients as stage BR-B. In total, 253 patients were considered R. The cohort did not contain BR-C patients. No differences in postoperative complications were detected. Median OS was significantly shorter in BR-A (15 months) and BR-B (12 months) compared with R (20 months) patients (BR-A vs. R: p = 0.09 and BR-B vs. R: p < 0.001). CA19-9, as the determining factor of BR-B patients, turned out to be an independent prognostic risk factor for OS. CONCLUSIONS: Preoperative staging defining surgical resectability in PDAC according to ICC is crucial for patient survival. Patients with PDAC BR-B should be considered for multimodal neoadjuvant therapy even if considered anatomically resectable.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Biología , Carcinoma Ductal Pancreático/cirugía , Consenso , Humanos , Terapia Neoadyuvante , Neoplasias Pancreáticas/cirugía , Estudios Retrospectivos
13.
J Appl Stat ; 48(7): 1180-1198, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35706886

RESUMEN

Skewness is a well-established statistical concept for continuous and, to a lesser extent, for discrete quantitative statistical variables. However, for ordered categorical variables, limited literature concerning skewness exists, although this type of variables is common for behavioral, educational, and social sciences. Suitable measures of skewness for ordered categorical variables have to be invariant with respect to the group of strictly increasing, continuous transformations. Therefore, they have to depend on the corresponding maximal-invariants. Based on these maximal-invariants, we propose a new class of skewness functionals, show that members of this class preserve a suitable ordering of skewness and derive the asymptotic distribution of the corresponding skewness statistic. Finally, we show the good power behavior of the corresponding skewness tests and illustrate these tests by applying real data examples.

14.
Entropy (Basel) ; 22(1)2020 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33285866

RESUMEN

A distribution that maximizes an entropy can be found by applying two different principles. On the one hand, Jaynes (1957a,b) formulated the maximum entropy principle (MaxEnt) as the search for a distribution maximizing a given entropy under some given constraints. On the other hand, Kapur (1994) and Kesavan and Kapur (1989) introduced the generalized maximum entropy principle (GMaxEnt) as the derivation of an entropy for which a given distribution has the maximum entropy property under some given constraints. In this paper, both principles were considered for cumulative entropies. Such entropies depend either on the distribution function (direct), on the survival function (residual) or on both (paired). We incorporate cumulative direct, residual, and paired entropies in one approach called cumulative Φ entropies. Maximizing this entropy without any constraints produces an extremely U-shaped (=bipolar) distribution. Maximizing the cumulative entropy under the constraints of fixed mean and variance tries to transform a distribution in the direction of a bipolar distribution, as far as it is allowed by the constraints. A bipolar distribution represents so-called contradictory information, which is in contrast to minimum or no information. In the literature, to date, only a few maximum entropy distributions for cumulative entropies have been derived. In this paper, we extended the results to well known flexible distributions (like the generalized logistic distribution) and derived some special distributions (like the skewed logistic, the skewed Tukey λ and the extended Burr XII distribution). The generalized maximum entropy principle was applied to the generalized Tukey λ distribution and the Fechner family of skewed distributions. Finally, cumulative entropies were estimated such that the data was drawn from a maximum entropy distribution. This estimator will be applied to the daily S&P500 returns and time durations between mine explosions.

15.
HPB (Oxford) ; 22(10): 1384-1393, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31980308

RESUMEN

BACKGROUND: The aim of this study was to evaluate the prognostic impact of simultaneous venous resection during pancreaticoduodenectomy (PD) for pancreatic adenocarcinoma (PDAC) that was preoperatively staged resectable according to NCCN guidelines. METHODS: A retrospective analysis of 153 patients who underwent PD for PDAC was performed. Patients were divided into standard PD and PD with simultaneous vein resection (PDVR). Groups were compared to each other in terms of postoperative morbidity and mortality, disease free (DFS) and overall survival (OS). RESULTS: 114 patients received PD while 39 patients received PDVR. No differences in terms of postoperative morbidity and mortality between both groups were detected. Patients in the VR group presented with a significantly shorter OS in the median (13 vs. 21 months, P = 0.011). In subgroup analysis, resection status did not influence OS in the PDVR group (R0 13 vs. R1 12 months, P = 0.471) but in the PD group (R0 23 vs. R1 14 months, P = 0.043). PDVR was a risk factor of OS in univariate but not multivariable analysis. CONCLUSION: PDVR for PDAC preoperatively staged resectable resulted in significantly shorter OS regardless of resection status. Patients who require PDVR should be considered for adjuvant chemotherapy in addition to other oncological indications.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Venas Mesentéricas , Neoplasias Pancreáticas/cirugía , Pronóstico , Estudios Retrospectivos
16.
Stem Cells Dev ; 28(21): 1451-1462, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31495270

RESUMEN

Hepatic ischemia reperfusion injury (IRI) remains a major obstacle in liver resection and transplantation surgery, especially in diseased organs. Human mesenchymal stromal cells (MSCs) are reported to acutely alleviate hepatic IRI in mice by releasing bioactive membrane-enclosed extracellular vesicles (EVs), but the long-term effects of MSC-derived EV on hepatic IRI are unknown. Given the considerable differentiation capacity of fibroblasts (FBs) during wound healing and their morphological similarities with MSC, the present study aimed to investigate the potential of these two cell types and their cell-derived EV in attenuating liver damage after IRI. EVs were isolated and purified from the supernatant of MSC and FB cultures and, subsequently, characterized by electron microscopy, nanoparticle tracking analysis, and western blot. Liver injury and organ regeneration in a murine in vivo model of IRI were assessed by serum transaminase levels, histopathology, and immunohistochemistry. Changes in expression of inflammation-associated genes within liver tissue were evaluated by reverse transcriptase quantitative polymerase chain reaction. MSC, MSC-derived EV, FB, and FB-derived EV were systemically administered before hepatic IRI. We found that MSC and MSC-derived EV decreased serum transaminase levels, reduced hepatic necrosis, increased the amount of Ki67-positive hepatocytes, and repressed the transcription of inflammation-associated genes. Although they had no impact on organ damage, FB and FB-derived EV showed some regenerative potential in the late phase of hepatic IRI. Compared to FB, MSC and their derived EV had a stronger potential to attenuate liver damage and improve organ regeneration after hepatic IRI. These results suggest that the key therapeutic factors are located within EV.


Asunto(s)
Vesículas Extracelulares/trasplante , Regeneración Hepática/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Daño por Reperfusión/terapia , Animales , Proliferación Celular/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Células Cultivadas , Modelos Animales de Enfermedad , Hepatocitos/metabolismo , Humanos , Hígado/lesiones , Células Madre Mesenquimatosas/fisiología , Ratones , Daño por Reperfusión/patología , Transaminasas/sangre
17.
Cancer Immunol Immunother ; 68(4): 563-575, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30671614

RESUMEN

The prognostic value of the local immune phenotype in patients with colorectal cancer has been extensively studied. Neoadjuvant radiotherapy and/or chemotherapy may potentially influence these immune responses. In this study, we examined the prognostic role of indoleamine-2,3-Dioxygenase (IDO1) and infiltrating cytotoxic T lymphocytes (CD8+) in locally advanced rectal carcinomas after neoadjuvant treatment. Expression of IDO1 and CD8 was evaluated by immunohistochemistry in 106 archival tumour tissue samples from patients following neoadjuvant chemoradiation and radical resection. The average infiltration of IDO1+ and CD8+ cells was calculated along the tumour invasive front, in the tumour centre and within the neoplastic cells and expressed as total scores. Of the tumour specimens evaluable for immunohistochemistry, 100% showed CD8+ lymphocyte infiltration and 93.4% stained positive for IDO1. Total IDO1 score positively correlated with total CD8 score for all three subsites (p = 0.002, Kendall-tau-b 0.357). A high total CD8 score was positively correlated with lower ypUICC-stages (p = 0.047) and lower ypT-categories (p = 0.032). Total IDO1 expression showed a clear trend towards a lower risk of recurrence (p = 0.078). A high total IDO1 score was an independent prognostic marker for prolonged disease-free survival (HR 0.38, p = 0.046) and a high total CD8 score for favourable overall survival (HR 0.16, p = 0.029). Analysis of the local CD8 and IDO1 expression profile may be a helpful tool in predicting prognosis for patients with locally advanced rectal cancer following neoadjuvant chemoradiation.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Neoplasias del Recto/inmunología , Neoplasias del Recto/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Linfocitos T CD8-positivos/metabolismo , Quimioradioterapia , Femenino , Humanos , Inmunohistoquímica , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Estimación de Kaplan-Meier , Linfocitos Infiltrantes de Tumor/metabolismo , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Neoplasias del Recto/patología , Neoplasias del Recto/terapia
18.
PLoS One ; 14(1): e0209825, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30673740

RESUMEN

BACKGROUND: Epidural catheters are state of the art for postoperative analgesic in abdominal surgery. Due to neurolysis it can lead to postoperative urinary tract retention (POUR), which leads to prolonged bladder catheterization, which has an increased risk for urinary tract infections (UTI). Our aim was to identify the current perioperative management of urinary catheters and, second, to identify the optimal time of suprapubic bladder catheter removal in regard to the removal of the epidural catheter. METHODS: We sent a questionnaire to 102 German hospitals and analyzed the 83 received answers to evaluate the current handling of bladder drainage and epidural catheters. Then, we conducted a retrospective study including 501 patients, who received an epidural and suprapubic catheter after abdominal surgery at the University Hospital Würzburg. We divided the patients into three groups according to the point in time of suprapubic bladder drainage removal in regard to the removal of the epidural catheter and analyzed the onset of a UTI. RESULTS: Our survey showed that in almost all hospitals (98.8%), patients received an epidural catheter and a bladder drainage after abdominal surgery. The point in time of urinary catheter removal was equally distributed between before, simultaneously and after the removal of the epidural catheter (respectively: ~28-29%). The retrospective study showed a catheter-associated UTI in 6.7%. Women were affected significantly more often than men (10,7% versus 2,5%, p<0.001). There was a non-significant trend to more UTIs when the suprapubic catheter was removed after the epidural catheter (before: 5.7%, after: 8.4%). CONCLUSION: The point in time of suprapubic bladder drainage removal in relation to the removal of the epidural catheter does not seem to correlate with the rate of UTIs. The current handling in Germany is inhomogeneous, so further studies to standardize treatment are recommended.


Asunto(s)
Cistostomía/métodos , Cateterismo Urinario/efectos adversos , Infecciones Urinarias/prevención & control , Adulto , Anciano , Anestesia Epidural/efectos adversos , Catéteres de Permanencia/efectos adversos , Remoción de Dispositivos/efectos adversos , Drenaje/efectos adversos , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Periodo Posoperatorio , Estudios Retrospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Vejiga Urinaria/cirugía , Catéteres Urinarios/efectos adversos , Retención Urinaria/etiología , Infecciones Urinarias/etiología
19.
Innov Surg Sci ; 4(4): 144-151, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33977124

RESUMEN

About 10% of patients taking a chronic, oral anticoagulant therapy require an invasive procedure that can be associated with an increased risk for peri-interventional or perioperative bleeding. Depending on the risk for thromboembolism and the risk for bleeding, the physician has to decide whether the anticoagulant therapy should be interrupted or continued. Patient characteristics such as age, renal function and drug interactions must be considered. The perioperative handling of the oral anticoagulant therapy differs according to the periprocedural bleeding risk. Patients requiring a procedure with a minor risk for bleeding do not need to pause their anticoagulant therapy. For procedures with an increased risk for perioperative bleeding, the anticoagulant therapy should be adequately paused. For patients on a coumarin derivative with a high risk for a thromboembolic event, a perioperative bridging therapy with a low molecular weight heparin is recommended. Due to an increased risk for perioperative bleeding in patients on a bridging therapy, it is not recommended in patients with a low risk for thromboembolism. For patients taking a non-vitamin K oral anticoagulant, a bridging therapy is not recommended due to the fast onset and offset of the medication.

20.
Front Immunol ; 9: 1338, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29946322

RESUMEN

The immune suppressants cyclosporin A (CsA) and tacrolimus (FK506) are used worldwide in transplantation medicine to suppress graft rejection. Both CsA and FK506 inhibit the phosphatase calcineurin (CN) whose activity controls the immune receptor-mediated activation of lymphocytes. Downstream targets of CN in lymphocytes are the nuclear factors of activated T cells (NFATs). We show here that the activity of NFATc1, the most prominent NFAT factor in activated lymphocytes supports the acute rejection of heterotopic heart allografts. While ablation of NFATc1 in T cells prevented graft rejection, ectopic expression of inducible NFATc1/αA isoform led to rejection of heart allografts in recipient mice. Acceptance of transplanted hearts in mice bearing NFATc1-deficient T cells was accompanied by a reduction in number and cytotoxicity of graft infiltrating cells. In CD8+ T cells, NFATc1 controls numerous intracellular signaling pathways that lead to the metabolic switch to aerobic glycolysis and the expression of numerous lymphokines, chemokines, and their receptors, including Cxcr3 that supports the rejection of allogeneic heart transplants. These findings favors NFATc1 as a molecular target for the development of new strategies to control the cytotoxicity of T cells upon organ transplantation.

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