Membrane composite a base di Lupamin 9095, grafene e grafene ossido per applicazioni carbon capture: purificazione del materiale, sintesi e caratterizzazione delle membrane

Il progetto di questa tesi sperimentale riguarda la preparazione di membrane polimeriche composite per separazione di gas, nello specifico per applicazioni di carbon capture, ovvero il sequestro di anidride carbonica. Come matrice è stato utilizzato un polimero a base di polivinilammina in quanto riesce a esplicare il così detto "trasporto facilitato" della CO2; come rinforzanti sono stati utilizzati grafene e grafene ossido, per via delle loro eccezionali caratteristiche di rigidità e resistenza meccanica. Il lavoro di tesi sperimentale si è articolato attorno 3 attività principali: 1) purificazione del prodotto commerciale di partenza, Lupamin 9095, per ottenere il polimero a base di polivinilammina 2) caratterizzazioni chimico-fisiche per monitorare la purificazione del prodotto, caratterizzare il materiale purificato e caratterizzare le membrane preparate. Nel complesso sono state applicate le analisi FT-IR ATR, DSC, TGA, SEM e SEM-EDX. 3) test di permeazione delle membrane ottenute per valutarne la permeabilità di CO2 e selettività CO2/N2, parametri fondamentali per determinare le performances delle membrane

Long-Standing Pancreatic Hyperenzymemia: Is It a Nonpathological Condition?

Chronic nonpathological pancreatic hyperenzymemia is characterized by a chronic, abnormal increase in the serum concentrations of the pancreatic enzymes including amylase, pancreatic isoamylase, lipase and trypsin. The diagnostic work-up that the physicians should recommend to subjects with hyperenzymemia to definitively assess this syndrome is still an open question. A 72-year-old female was admitted to our Pancreas Unit in December 2008 for the presence of long-standing pancreatic hyperenzymemia of 42 years duration. On admission, serum amylase activity was 160 IU/l (reference range 8–78 IU/l), serum pancreatic isoamylase activity was 91 IU/l (reference range 13–53 IU/l) and serum lipase activity was 127 IU/l (reference range 8–78 IU/l). Other laboratory examinations revealed normal blood tests except for total serum cholesterol, HDL cholesterol and serum triglycerides that was slight elevated. Abdominal ultrasonography demonstrated no alteration of the pancreatic gland. A magnetic resonance cholangiopancreatography was carried out according to our diagnostic work-up of patients with unexplained pancreatic hyperenzymemia. This examination revealed two small cystic lesions: one of 6 mm in diameter in the head of the pancreas and the other one of 9 mm in diameter in the body of the pancreatic gland. The duct of Wirsung was normal and the two cystic lesions were diagnosed as branch-type intrapapillary mucinous tumors of the pancreas. All patients with pancreatic hyperenzymemia should be strictly followed in high volume centers for pancreatic disease in order to early diagnose the possible appearance of morphological pancreatic alterations

Author response to: Survival after active surveillance versus upfront surgery for incidental small pancreatic neuroendocrine tumours

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A [68Ga]Ga-DOTANOC PET/CT radiomic model for non-invasive prediction of tumour grade in pancreatic neuroendocrine tumours

Predicting grade 1 (G1) and 2 (G2) primary pancreatic neuroendocrine tumour (panNET) is crucial to foresee panNET clinical behaviour. 51 patients with G1-G2 primary panNET demonstrated by pre-surgical [68Ga]Ga-DOTANOC PET/CT and diagnostic conventional imaging were grouped according to the tumour grade assessment method: histology on the whole excised primary lesion (HS) or biopsy (BS). First-order and second-order radiomic features (RFs) were computed from SUV maps for the whole tumour volume on HS. The RFs showing the lowest p-values and the highest Area Under the Curve (AUC) were selected. Three radiomic models were assessed: A (trained on HS, validated on BS), B (trained on BS, validated on HS), C (using the cross-validation on the whole dataset). The second-order Normalized homogeneity and Entropy was the most effective RFs couple predicting G2 and G1. The best performance was achieved by model A (test AUC=0.90, sensitivity=0.88, specificity=0.89), followed by model C (median test AUC=0.87, sensitivity=0.83, specificity=0.82). Model B performed worse. Using HS to train a radiomic model leads to the best prediction, although a “hybrid” (HS+BS) population performs better than biopsy-only. The non-invasive prediction of panNET grading may be especially useful in lesions not amenable to biopsy while [68Ga]Ga-DOTANOC heterogeneity might recommend FDG PET/CT

Appendiceal goblet cell carcinoma has marginal advantages from perioperative chemotherapy: a population-based study with an entropy balancing analysis

PurposeThe aim is to clarify the use of perioperative chemotherapy in resectable goblet cell carcinoma (GCC).MethodsA retrospective study was carried out based on the Surveillance, Epidemiology, and End Results study. The population was divided: into patients who received only radical surgery (group A) and those who received radical surgery plus chemotherapy (group B). An entropy balancing was carried out to correct the imbalance between the two groups. Two models were generated. Model 1 contained only high-risk patients: group B and a "virtual" group A with similar characteristics. Model 2 included only low-risk patients: group A and "virtual" group B with identical attributes. The efficacy of entropy balancing was evaluated with the d value. The overall survival was compared and reported with Hazard Ratio (HR) within a confidence interval of 95% (95 CI).ResultsThe groups A and B were imbalanced for tumor size (d = 0.392), T (d = 1.128), N (d = 1.340), M (d = 1.456), mean number of positive lymph nodes (d = 0.907), and LNR (d = 0.889). Before the balancing, the risk of death was higher in group B than in A (4.3; 2.5 to 7.4). After reweighting, all large differences were eliminated (d < 0.200). In high-risk patients, the risk of death was higher in patients who underwent surgery alone than those who received perioperative chemotherapy (HR 0.5; 0.2 to 1.3) without statistical significance (p = 0.187). In low-risk patients, the risk of death was similar (HR 1.1; 0.3 to 3.3).ConclusionPerioperative chemotherapy could provide some marginal advantages to high-risk patients

Lactate Dehydrogenase in Hepatocellular Carcinoma: Something Old, Something New

Hepatocellular carcinoma (HCC) is the most common primary liver tumour (80-90%) and represents more than 5.7% of all cancers. Although in recent years the therapeutic options for these patients have increased, clinical results are yet unsatisfactory and the prognosis remains dismal. Clinical or molecular criteria allowing a more accurate selection of patients are in fact largely lacking. Lactic dehydrogenase (LDH) is a glycolytic key enzyme in the conversion of pyruvate to lactate under anaerobic conditions. In preclinical models, upregulation of LDH has been suggested to ensure both an efficient anaerobic/glycolytic metabolism and a reduced dependence on oxygen under hypoxic conditions in tumour cells. Data from several analyses on different tumour types seem to suggest that LDH levels may be a significant prognostic factor. The role of LDH in HCC has been investigated by different authors in heterogeneous populations of patients. It has been tested as a potential biomarker in retrospective, small, and nonfocused studies in patients undergoing surgery, transarterial chemoembolization (TACE), and systemic therapy. In the major part of these studies, high LDH serum levels seem to predict a poorer outcome. We have reviewed literature in this setting trying to resume basis for future studies validating the role of LDH in this disease

Cytochalasin B Modulates Nanomechanical Patterning and Fate in Human Adipose-Derived Stem Cells

Cytoskeletal proteins provide architectural and signaling cues within cells. They are able to reorganize themselves in response to mechanical forces, converting the stimuli received into specific cellular responses. Thus, the cytoskeleton influences cell shape, proliferation, and even differentiation. In particular, the cytoskeleton affects the fate of mesenchymal stem cells (MSCs), which are highly attractive candidates for cell therapy approaches due to their capacity for self-renewal and multi-lineage differentiation. Cytochalasin B (CB), a cyto-permeable mycotoxin, is able to inhibit the formation of actin microfilaments, resulting in direct effects on cell biological properties. Here, we investigated for the first time the effects of different concentrations of CB (0.1–10 μM) on human adipose-derived stem cells (hASCs) both after 24 h (h) of CB treatment and 24 h after CB wash-out. CB influenced the metabolism, proliferation, and morphology of hASCs in a dose-dependent manner, in association with progressive disorganization of actin microfilaments. Furthermore, the removal of CB highlighted the ability of cells to restore their cytoskeletal organization. Finally, atomic force microscopy (AFM) revealed that cytoskeletal changes induced by CB modulated the viscoelastic properties of hASCs, influencing their stiffness and viscosity, thereby affecting adipogenic fat

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ABSTRACT Context The absence of a definition and a widely accepted ranking system to classify surgical complications has hampered proper interpretation of the surgical outcome. Patients Sixty-one patients undergoing distal pancreatectomy. Main outcome measures The complications were classified according to the Clavien-Dindo classification; each grade was evaluated regarding the length of the postoperative stay and was compared to the most important complications. Results Thirty (49.2%) patients had no complications; out of the thirty-one (50.8%) patients with complications, 9 (14.5%) had grade I, 15 (24.6%) had grade II, 6 (9.8%) had grade III, and 1 (1.6%) had grade IV. There were no postoperative deaths (grade V). A progressive increase in the length of hospitalization from patients with no complications to those having grade IV (P<0.001) was noted. Postoperative pancreatic fistula and postpancreatectomy hemorrhage rates did not significantly increase from Clavien-Dindo grade I to grade IV (P=0.118 and P=0.226, respectively). The severity of a postpancreatectomy hemorrhage, instead, was positively related to the grade of the Clavien-Dindo classification (P=0.049) while postoperative pancreatic fistula resulted near the significant value (P=0.058). Conclusions The Clavien-Dindo classification is a simple way of reporting all complications following distal pancreatectomy. It allows us to distinguish a normal postoperative course from any deviation and the severity of complications and it may be useful for comparing postoperative morbidity between different pancreatic centers

Sarcopenia in gastric cancer: when the loss costs too much

Sarcopenia is a complex syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength. Malignancy is a major determinant of sarcopenia, and gastric cancer (GC) is among the most common causes of this phenomenon. As sarcopenia is a well-recognized poor prognostic feature in GC and has been associated with worse tolerance of surgical and medical treatments, members of the multidisciplinary team should be aware of the clinical relevance, pathogenic mechanisms, and potential treatments for this syndrome. The importance of sarcopenia is often underestimated in everyday practice and clinical trials, particularly among elderly or fragile patients. As treatment options are improving in all disease stages, deeper knowledge and greater attention to the metabolic balance in GC patients could further increase the benefit of novel therapeutic strategies and dramatically impact on quality of life. In this review, we describe the role of sarcopenia in different phases of GC progression. Our aim is to provide oncologists and surgeons dealing with GC patients with a useful tool for comprehensive assessment and timely management of this potentially life-threatening condition