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81.
82.

Background:

Resection of liver metastases from neuroendocrine cancer (NEC) prolongs survival and provides durable symptom relief. Not all hepatic lesions are amenable to resection, particularly when there is multifocal involvement. In this study, it was hypothesized that ablation of concomitant non-resectable NEC liver metastases is safe and salvages patients who would not have been selected for cytoreductive surgery.

Methods:

Patients who underwent adjuvant ablation of NEC liver metastases between 1995 and 2008 were reviewed. NEC was classified by patient and tumour characteristics. Regression and Kaplan–Meier models were used to compare variables and generate survival curves.

Results:

Ninety-four patients underwent hepatic resection and intra-operative ablation of metastatic NEC. The median number of lesions ablated was 3, and median size was 1.4 cm. One abscess occurred at an ablation site. Local recurrence was detected in four patients (3.8%). Overall survival was 80% and 59% at 5 and 10 years. Age, gender, tumour type, grade, primary site and need for repeat ablation had no significant association with survival. The Ki67 proliferative index was a significant predictor of decreased survival. Symptom-free survival was 34% at 3 years and 16% at 5 years, independent of the tumour grade.

Conclusion:

Concurrent ablation of NEC metastases to the liver not amenable to resection is safe and increases the candidacy of patients for cytoreductive surgery. Ablation performed intra-operatively and repeated post-operatively as needed provides significant symptom control regardless of the tumour grade.  相似文献   
83.
ABSTRACT

Introduction: Cachexia and sarcopenia are conditions phenotypically characterized by muscle loss and represent a factor of poor prognosis, increasing patients’ morbidity and mortality. Cachectic and sarcopenic patients often suffer from low quality of life, presenting lower muscle strength and appetite loss, which makes research on novel treatment strategies to ameliorate clinical response including patient’s symptoms, the objective of scientific interest.

Areas covered: This article covers recent developments in the area of cachexia and sarcopenia treatment and therapeutic interventions, targeting central nervous system involvement, key inflammatory and muscle-specific metabolic pathways.

Expert opinion: A number of promising agents have being evaluated, such as enobosarm, a selected androgen receptor modulator, and anamorelin, a ghrelin agonist which have been recently studied in phase III trials. These and other agents (i.e., infliximab, tocilizumab, MABp1, bimagrumab) have shown significant impact on reversal of skeletal muscle loss, but limited effect on physical function.

In the last few years advancement in the number and type of potential treatments for cachexia and sarcopenia have been obtained and we have now available more data on measurable effects of several drugs on patients’ nutritional and metabolic parameters and outcomes.  相似文献   
84.
BACKGROUNDPancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with unpredictable responses to chemotherapy. Approaches to assay patient tumors before treatment and identify effective treatment regimens based on tumor sensitivities are lacking. We developed an organoid-based platform (OBP) to visually quantify patient-derived organoid (PDO) responses to drug treatments and associated tumor-stroma modulation for personalized PDAC therapy.METHODSWe retrospectively quantified apoptotic responses and tumor-stroma cell proportions in PDOs via 3D immunofluorescence imaging through annexin A5, α-smooth muscle actin (α-SMA), and cytokeratin 19 (CK-19) levels. Simultaneously, an ex vivo organoid drug sensitivity assay (ODSA) was used to measure responses to standard-of-care regimens. Differences between ODSA results and patient tumor responses were assessed by exact McNemar’s test.RESULTSImmunofluorescence signals, organoid growth curves, and Ki-67 levels were measured and authenticated through the OBP for up to 14 days. ODSA drug responses were not different from patient tumor responses, as reflected by CA19-9 reductions following neoadjuvant chemotherapy (P = 0.99). PDOs demonstrated unique apoptotic and tumor-stroma modulation profiles (P < 0.0001). α-SMA/CK-19 ratio levels of more than 1.0 were associated with improved outcomes (P = 0.0179) and longer parental patient survival by Kaplan-Meier analysis (P = 0.0046).CONCLUSIONHeterogenous apoptotic drug responses and tumor-stroma modulation are present in PDOs after standard-of-care chemotherapy. Ratios of α-SMA and CK-19 levels in PDOs are associated with patient survival, and the OBP could aid in the selection of personalized therapies to improve the efficacy of systemic therapy in patients with PDAC.FUNDINGNIH/National Cancer Institute grants (K08CA218690, P01 CA117969, R50 CA243707-01A1, U54CA224065), the Skip Viragh Foundation, the Bettie Willerson Driver Cancer Research Fund, and a Cancer Center Support Grant for the Flow Cytometry and Cellular Imaging Core Facility (P30CA16672).  相似文献   
85.
SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.  相似文献   
86.
Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer  相似文献   
87.
Background Ustekinumab is a fully human anti‐p40 monoclonal antibody which neutralizes interleukin (IL)‐12 and IL‐23, thereby interfering with T‐helper (Th)1/Th17 pathways and keratinocyte activation, and is highly effective in the treatment of psoriasis. During ustekinumab treatment, some of our patients noticed reduced koebnerization of noninvolved skin and less new plaque formation. Objectives To determine whether ustekinumab improves psoriasis‐related gene expression and tape‐strip responses in noninvolved skin. Methods Before and 4 weeks after ustekinumab treatment, noninvolved skin was tape‐stripped. After 5 h, biopsies were taken from untouched and tape‐stripped skin. The mRNA expression of psoriasis‐related markers such as NGF, GATA3 and IL‐22RA1, and several antimicrobial peptides (AMP) was quantified. Leucocyte counts and a broad range of inflammatory serum proteins were analysed to gain insight into the systemic alterations. Results Four weeks following a single ustekinumab injection, NGF showed a significant decrease, whereas GATA3 and IL‐22RA1 expression increased, indicative of reduced responsiveness to epidermal triggering. This was accompanied by an increase of the inflammation‐related serum proteins GPNMB, MST1 and TRADD. The baseline and tape‐strip‐induced mRNA expression of the AMP human β‐defensin‐2 (hBD‐2), S100A7 and LL‐37 remained unaltered. Clinically, after 4 weeks, eight out of 11 patients showed a 50% psoriasis area and severity index (PASI) improvement, which was accompanied by a significant reduction in serum hBD‐2 levels. No changes were noted in total leucocytes, C‐reactive protein and erythrocyte sedimentation rate. Conclusions These findings indicate that ustekinumab reduces psoriasis‐related gene expression in noninvolved psoriatic skin, making it more resistant to exogenous triggering, without disturbing its antimicrobial response. In parallel, ustekinumab modulates important circulating inflammation‐related proteins.  相似文献   
88.
Major hepatic resection for hilar cholangiocarcinoma: analysis of 46 patients   总被引:21,自引:0,他引:21  
HYPOTHESIS: Major hepatectomy, bile duct resection, and regional lymphadenectomy for hilar cholangiocarcinoma are associated with actual long-term (>5 years) survival. DESIGN: Retrospective outcome study. SETTING: Single tertiary referral institution. PATIENTS: Between 1979 and 1997, 46 consecutive patients had resection of hilar cholangiocarcinoma by major hepatectomy, bile duct resection, and regional lymphadenectomy. MAIN OUTCOME MEASURES: Overall survival and tumor recurrence were correlated to clinicopathological factors, operative morbidity, and mortality. RESULTS: Twenty-five patients underwent left hepatectomy, 17 underwent right hepatectomy, and 4 had extended right hepatectomy. Eighteen patients underwent resection of segment 1. Negative (R0) resection margins were achieved in 37 patients (80%). The operative mortality rate was 9%, and the surgical morbidity rate was 52%. Actual 1-year, 3-year, and 5-year survival rates were 80%, 39%, and 26%, respectively. Factors adversely associated with patient survival rates included: male sex, lymph node metastases, tumor grade 3 or 4, elevated direct serum bilirubin level at diagnosis, elevated preoperative activated partial thromboplastin time, and more than 4 U of red blood cells transfused perioperatively. Tumor size and R0 resection approached significance for survival. Factors associated with tumor recurrence included: male sex, tumor grade 3 or 4, a low hemoglobin level both at diagnosis and preoperatively, and a low preoperative prothrombin time and low alkaline phosphatase level at diagnosis and preoperatively. Median time to recurrence was 3.6 years. Tumor recurrence was predominantly local and regional. CONCLUSIONS: The actual 5-year survival rate of 26% justifies major partial hepatectomy, bile duct resection, and regional lymphadenectomy for hilar cholangiocarcinoma. The high frequency of local and regional recurrence warrants investigation of adjuvant therapy.  相似文献   
89.
90.
The development of neural network models has greatly enhanced the comprehension of cognitive phenomena. Here, we show that models using multiplicative processing of inputs are both powerful and simple to train and understand. We believe they are valuable tools for cognitive explorations. Our model can be viewed as a subclass of networks built on sigma-pi units and we show how to derive the Kronecker product representation from the classical sigma-pi unit. We also show how the connectivity requirements of the Kronecker product can be relaxed considering statistical arguments. We use the multiplicative network to implement what we call an Elman topology, that is, a simple recurrent network (SRN) that supports aspects of language processing. As an application, we model the appearance of hallucinated voices after network damage, and show that we can reproduce results previously obtained with SRNs concerning the pathology of schizophrenia.  相似文献   
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