A Substrate-induced Switch in the Reaction Mechanism of a Thermophilic Esterase KINETIC EVIDENCES AND STRUCTURAL BASIS

The reaction mechanism of the esterase 2 (EST2) from Alicyclobacillus acidocaldarius was studied at the kinetic and structural level to shed light on the mechanism of activity and substrate specificity increase previously observed in its double mutant M211S/R215L. In particular, the values of kinetic constants (k1, k(-1), k2, and k3) along with activation energies (E1, E(-1), E2, and E3) were measured for wild type and mutant enzyme. The previously suggested substrate-induced switch in the reaction mechanism from kcat=k3 with a short acyl chain substrate (p-nitrophenyl hexanoate) to kcat=k2 with a long acyl chain substrate (p-nitrophenyl dodecanoate) was validated. The inhibition afforded by an irreversible inhibitor (1-hexadecanesulfonyl chloride), structurally related to p-nitrophenyl dodecanoate, was studied by kinetic analysis. Moreover the three-dimensional structure of the double mutant bound to this inhibitor was determined, providing essential information on the enzyme mechanism. In fact, structural analysis explained the observed substrate-induced switch because of an inversion in the binding mode of the long acyl chain derivatives with respect to the acyl- and alcohol-binding sites

Uso di tecnologia GIS per l’analisi del degrado di beni archeologici e/o architettonici

Il SIT per l'analisi del degrado di beni architettonici e/o archeologici del centro antico di Napoli crea un sistema che consente il riconoscimento e il geo-posizionamento dei beni culturali e un collegamento con il database delle schede di rilievo che registrano indicatori chimico-fisici e strutturali del bene. Attraverso strumenti di analisi spaziale si analizza il degrado registrato (e potenziale) sul bene nonché il degrado che deriva dal contesto ambientale in cui ricade. Attraverso l'obiettivo è proporre un Sistema Informativo Territoriale a scala urbana e creare la Carta del rischio locale dei beni culturali

Risk of Hepatocellular Carcinoma after HCV Clearance by Direct-Acting Antivirals Treatment. Predictive Factors and Role of Epigenetics

Abstract: Direct-acting antivirals (DAAs) induce a rapid virologic response (SVR) in up to 99% of chronic hepatitis C patients. The role of SVR by DAAs on the incidence or recurrence of carcinoma (HCC) is still a matter of debate, although it is known that SVR does not eliminate the risk of HCC. In this review, we made an updated analysis of the literature data on the impact of SVR by DAAs on the risk of HCC as well as an assessment of risk factors and the role of epigenetics. Data showed that SVR has no impact on the occurrence of HCC in the short–medium term but reduces the risk of HCC in the medium–long term. A direct role of DAAs in the development of HCC has not been demonstrated, while the hypothesis of a reduction in immune surveillance in response to the rapid clearance of HCV and changes in the cytokine pattern influencing early carcinogenesis remains to be further elucidated. HCV induces epigenetic alterations such as modifications of the histone tail and DNA methylation, which are risk factors for HCC, and such changes are maintained after HCV clearance. Future epigenetic studies could lead to identify useful biomarkers and therapeutic targets. Cirrhosis has been identified as a risk factor for HCC, particularly if associated with high liver stiffness and α-fetoprotein values, diabetes and the male sex. Currently, considering the high number and health cost to follow subjects’ post-HCV clearance by DAAs, it is mandatory to identify those at high risk of HCC to optimize management

NAB-paclitaxel and gemcitabine in metastatic pancreatic ductal adenocarcinoma (PDAC): From clinical trials to clinical practice

BACKGROUND: Pancreatic adenocarcinoma is an aggressive disease with poor prognosis. In a randomized phase III trial, combination of Nab-paclitaxel (Nab-P) plus gemcitabine showed superior activity and efficacy in first-line treatment compared with gemcitabine alone. METHODS: Nab-P is not dispensed in Italy; however, we obtained this drug from our Ethics Committee for compassionate use. The aim of this study was to evaluate the efficacy and safety profile of this Nab-P and gemcitabine combination in a cohort of patients treated outside clinical trials. From January 2012 to May 2014, we included 41 patients with advanced pancreatic adenocarcinoma receiving combination of 125 mg/m(2) Nab-P and 1 g/m(2) gemcitabine on days 1, 8 and 15 of a 28-day cycle, as first-line treatment. Median age of patients was 67 (range 41-77) years, and 11 patients were aged ≥70 years. RESULTS: Eastern Co-operative Oncology Group performance status was 0 or 1 in 32 patients (78 %) and 2 in nine patients (22 %). Primary tumor was located in the pancreatic head or body/tail in 24 (58.5 %) and 17 (41.5 %) patients, respectively, and nine patients had received biliary stent implantation before starting chemotherapy. Median carbohydrate antigen 19-9 level was 469 U/l (range 17.4-61546 U/l) and 29 patients (70.7 %) had referred pain at the time of diagnosis. Patients received a median six cycles (range 1-14) of treatment. Overall response rate was 36.6 %; median progression-free survival was 6.7 months [(95 % confidence interval (CI) 5.966-8.034), and median overall survival was 10 months (95 % CI 7.864-12.136). Treatment was well tolerated. No grade 4 toxicity was reported. Grade 3 toxicity included neutropenia in 10 patients (24.3 %), thrombocytopenia in five (12 %), anemia in three (7.3 %), diarrhea in four (9.7 %), nausea and vomiting in two (4.9 %), and fatigue in six (14.6 %). Finally, pain control was achieved in 24 of 29 patients (82.3 %) with a performance status improvement of 10 % according to the Karnofsky scale. CONCLUSIONS: Our results confirm that combination of gemcitabine plus Nab-P is effective both in terms of overall response rate, progression-free survival and overall survival, with a good safety profile.Background: Pancreatic adenocarcinoma is an aggressive disease with poor prognosis. In a randomized phase III trial, combination of Nab-paclitaxel (Nab-P) plus gemcitabine showed superior activity and efficacy in first-line treatment compared with gemcitabine alone. Methods: Nab-P is not dispensed in Italy; however, we obtained this drug from our Ethics Committee for compassionate use. The aim of this study was to evaluate the efficacy and safety profile of this Nab-P and gemcitabine combination in a cohort of patients treated outside clinical trials. From January 2012 to May 2014, we included 41 patients with advanced pancreatic adenocarcinoma receiving combination of 125 mg/m2 Nab-P and 1 g/m2 gemcitabine on days 1, 8 and 15 of a 28-day cycle, as first-line treatment. Median age of patients was 67 (range 41-77) years, and 11 patients were aged ≥70 years. Results: Eastern Co-operative Oncology Group performance status was 0 or 1 in 32 patients (78 %) and 2 in nine patients (22 %). Primary tumor was located in the pancreatic head or body/tail in 24 (58.5 %) and 17 (41.5 %) patients, respectively, and nine patients had received biliary stent implantation before starting chemotherapy. Median carbohydrate antigen 19-9 level was 469 U/l (range 17.4-61546 U/l) and 29 patients (70.7 %) had referred pain at the time of diagnosis. Patients received a median six cycles (range 1-14) of treatment. Overall response rate was 36.6 %; median progression-free survival was 6.7 months [(95 % confidence interval (CI) 5.966-8.034), and median overall survival was 10 months (95 % CI 7.864-12.136). Treatment was well tolerated. No grade 4 toxicity was reported. Grade 3 toxicity included neutropenia in 10 patients (24.3 %), thrombocytopenia in five (12 %), anemia in three (7.3 %), diarrhea in four (9.7 %), nausea and vomiting in two (4.9 %), and fatigue in six (14.6 %). Finally, pain control was achieved in 24 of 29 patients (82.3 %) with a performance status improvement of 10 % according to the Karnofsky scale. Conclusions: Our results confirm that combination of gemcitabine plus Nab-P is effective both in terms of overall response rate, progression-free survival and overall survival, with a good safety profile

Vertebral carcinomatosis eleven years after advanced gastric cancer resection: A case report.

Bone metastasis is an uncommon event in advanced gastric cancer patients and bone metastases are rarely detected as isolated lesions. However, eleven years after treatment for locally advanced gastric cancer, including total gastrectomy followed by adjuvant chemotherapy, a 49-year-old female was admitted to the IX Division of General Surgery of the Second University of Naples (Naples, Italy) exhibiting severe progressive neurological symptoms. Magnetic resonance imaging indicated vertebral abnormalities, with evidence of marrow infiltration in several vertebral bodies; however, a contrast-enhanced computed tomography scan did not detect disease progression to other sites. Biopsy of the soft tissue at the level of the second lumbar vertebra (L2) revealed a metastatic lesion derived from gastric mucinous adenocarcinoma. The patient was initially treated with radiotherapy directed to the L2-L4 vertebral bodies to control the pain. Subsequently, systemic chemotherapy according to a FOLFOX-4 (leucovorin, fluorouracil and oxaliplatin) regimen commenced. However, after eight cycles, pulmonary progression of the disease occurred. Thus, palliative care was administered and the patient succumbed one month later. The late relapse of gastric cancer in the current patient may be associated with the theory of tumour dormancy

Distribution pattern of hepatitis C virus genotypes and correlation with viral load and risk factors in chronic positive patients.

Objective: Hepatitis C virus (HCV) has emerged as a leading cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. The purpose of this study was to describe the distribution pattern of HCV genotypes in chronic hepatitis patients in the Campania region of southern Italy and estimate their association with risk factors and viral load. Materials and Methods: 404 consecutive HCV ribonucleic acid-positive patients were included in the study. HCV genotyping was carried out by the HCV line probe assay test and viral load estimation by the TaqMan real-time PCR system. Results: The predominant genotype was 1 (63.6%), followed by genotype 2 (29.4%), 3 (6.2%) and 4 (0.8%). Subtype 1b was more frequent in females than in males. Conversely, genotype 3 was more frequent in males. No significant difference was observed in age distribution of HCV genotypes. Surgery and dental therapy were the most frequent risk factors for genotype 1 and intravenous drug abuse and tattooing for genotype 3. Patients with genotype 1 more frequently showed high HCV viral load when compared to those with genotypes 2 and 3. Conclusion: The present study revealed that HCV genotypes 1 and 2 accounted for over 95% of all HCV infections in the Campania region, and genotype 1 was more frequently associated with a higher viral load when compared to genotypes 2 and 3

coMpliAnce with evideNce-based cliniCal guidelines in the managemenT of acute biliaRy pancreAtitis): The MANCTRA-1 international audit

Background/objectives: Reports about the implementation of recommendations from acute pancreatitis guidelines are scant. This study aimed to evaluate, on a patient-data basis, the contemporary practice patterns of management of biliary acute pancreatitis and to compare these practices with the recommendations by the most updated guidelines. Methods: All consecutive patients admitted to any of the 150 participating general surgery (GS), hepatopancreatobiliary surgery (HPB), internal medicine (IM) and gastroenterology (GA) departments with a diagnosis of biliary acute pancreatitis between 01/01/2019 and 31/12/2020 were included in the study. Categorical data were reported as percentages representing the proportion of all study patients or different and well-defined cohorts for each variable. Continuous data were expressed as mean and standard deviation. Differences between the compliance obtained in the four different subgroups were compared using the Mann-Whitney U, Student's t, ANOVA or Kruskal-Wallis tests for continuous data, and the Chi-square test or the Fisher's exact test for categorical data. Results: Complete data were available for 5275 patients. The most commonly discordant gaps between daily clinical practice and recommendations included the optimal timing for the index CT scan (6.1%, χ2 6.71, P = 0.081), use of prophylactic antibiotics (44.2%, χ2 221.05, P < 0.00001), early enteral feeding (33.2%, χ2 11.51, P = 0.009), and the implementation of early cholecystectomy strategies (29%, χ2 354.64, P < 0.00001), with wide variability based on the admitting speciality. Conclusions: The results of this study showed an overall poor compliance with evidence-based guidelines in the management of ABP, with wide variability based on the admitting speciality. Study protocol registered in ClinicalTrials.Gov (ID Number NCT04747990)

Anti-metastatic Properties of Naproxen-HBTA in a Murine Model of Cutaneous Melanoma

The beneficial effects of H2S-release and of COXs-inhibition have been exploited in the design of novel anti-inflammatory drugs, the H2S-releasing non-steroidal anti-inflammatory drugs (H2S-NSAIDs), showing promising potential for chemoprevention in cancers. Here, we evaluated the efficacy of a new H2S-releasing derivative of naproxen, named naproxen-4-hydroxybenzodithioate (naproxen-HBTA), in reducing metastatic melanoma features, both in vitro and in vivo. The novel H2S donor has been prepared following a synthetic scheme that provided high yields and purity. In particular, we investigated the effect of naproxen-HBTA in vitro on several metastatic features of human melanoma cells such as proliferation, migration, invasion, and colonies formation and in vivo in a model of cutaneous melanoma. Cell culture studies demonstrated that naproxen-HBTA induced caspase 3-mediated apoptosis and inhibited motility, invasiveness, and focus formation. Finally, daily oral treatment with naproxen-HBTA significantly suppressed melanoma growth and progression in mice. In conclusion, by using this dual approach we propose that the COX-2 and H2S pathways could be regarded as novel therapeutic targets/tools to generate new treatment options based on “combination therapy” for melanoma