Kinetics of biodiesel production from microalgae using microbubble interfacial technology

As an alternative to fossil fuels, biodiesel can be a source of clean and environmentally friendly energy source. However, its commercial application is limited by expensive feedstock and the slow nature of the pretreatment step-acid catalysis. The conventional approach to carry out this reaction uses stirred tank reactors. Recently, the lab-scale experiments using microbubble mediated mass transfer technology have demonstrated its potential use at commercial scale. However, all the studies conducted so far have been at a lab scale~100 mL of feedstock. To analyze the feasibility of microbubble technology, a larger pilot scale study is required. In this context, a kinetic study of microbubble technology at an intermediate scale is conducted (3 L of oil). Owing to the target for industrial application of the process, a commercial feedstock (Spirulina), microalgae oil (MO) and a commercial catalyst para-toluene sulfonic acid (PTSA) are used. Experiments to characterize the kinetics space (response surface, RSM) required for up-scaling are designed to develop a robust model. The model is compared with that developed by the gated recurrent unit (GRU) method. The maximum biodiesel conversion of 99.45 ± 1.3% is achieved by using these conditions: the molar ratio of MO to MeOH of 1:23.73 ratio, time of 60 min, and a catalyst loading of 3.3 wt% MO with an MO volume of 3 L. Furthermore, predicted models of RSM and GRU show proper fits to the experimental result. It was found that GRU produced a more accurate and robust model with correlation coefficient R2 = 0.9999 and root-mean-squared error (RSME) = 0.0515 in comparison with RSM model with R2 = 0.9844 and RMSE = 3.0832, respectively. Although RSM and GRU are fully empirical representations, they can be used for reactor up-scaling horizontally with microbubbles if the liquid layer height is held constant while the microbubble injection replicates along the floor of the reactor vessel—maintaining the tessellation pattern of the smaller vessel. This scaling approach maintains the local mixing profile, which is the major uncontrolled variable in conventional stirred tank reactor up-scaling

Genetic factors affecting patient responses to pancreatic cancer treatment

Cancer of the exocrine pancreas is a malignancy with a high lethal rate. Surgical resection is the only possible curative mode of treatment. Metastatic pancreatic cancer is incurable with modest results from the current treatment options. New genomic information could prove treatment efficacy. An independent review of PubMed and Science Direct databases was performed up to March 2016, using combinations of terms such pancreatic exocrine cancer, chemotherapy, genomic profile, pancreatic cancer pharmacogenomics, genomics, molecular pancreatic pathogenesis, and targeted therapy. Recent genetic studies have identified new markers and therapeutic targets. Our current knowledge of pancreatic cancer genetics must be further advanced to elucidate the molecular basis and pathogenesis of the disease, improve the accuracy of diagnosis, and guide tailor-made therapies. © 2016 Hellenic Society of Gastroenterology

Hypersensitivity reactions associated with oxaliplatin and their clinical management

Introduction: Oxaliplatin, has become an integral part of the medical treatment of colorectal cancer and other malignancies. Increased use of the drug during the last decade, has led to increased occurrence of oxaliplatin-induced hypersensitivity reactions (HSRs), posing a significant challenge for clinicians. This article aims to review the existing literature regarding the incidence, clinical presentation, pathophysiology, risk factors and current management of oxaliplatin-induced HSRs. Areas covered: A systematic review of the English literature published in PubMed and Medline was undertaken. The clinical manifestations of HSRs were found to be variable and unpredictable. These reactions should be an important concern, as their potential life-threatening risks can force doctors to stop treatment and seek alternatives, which may be less effective, not as well tolerated and/or more expensive. There are a few strategies to prevent these reactions so that patients can still benefit from oxaliplatin. Such strategies include the use of premedication (steroid and antagonists of type I and II histamine receptors), prolonged infusion time and desensitization. Expert opinion: The presented management strategies as well as novel diagnostic tools including skin/intradermal tests and specific IgE have shown promising results. However, future research and validation are warranted in bigger clinical trials. © 2014 Informa UK, Ltd

The role of biliary drainage in patients with pancreatic adenocarcinoma

Pancreatic cancer is one of the leading causes of cancer deaths worldwide and constitutes a major public health problem. One of the most common symptoms associated with pancreatic adenocarcinoma is jaundice, caused by the obstruction of common bile duct. Endobiliary stenting is used to relief these patients either preoperatively or merely for palliation and plastic or metal stents are usually endoscopically or percutaneously placed. Two interesting studies were presented at the 2014 ASCO Gastrointestinal Cancers Symposium. Strom et al. sought to investigate the effect of preoperative biliary drainage on recurrence and survival and they concluded that percutaneous biliary decompression was an independent predictor of worse overall survival and was associated with non-significant increase in hepatic recurrence (Abstract #314). Montero et al. presented the results of their study regarding the cost-effectiveness of metal stents in patients with inoperable pancreatic cancer and they concluded that placement of metal biliary stents is cost saving, improves overall survival and quality-adjusted survival compared with plastic stents (Abstract #260). Both studies concluded to useful results that along with the existing literature and formulated guidelines may help the provision of more effective, higher quality management of these patients

The role of biliary drainage in patients with pancreatic adenocarcinoma

Pancreatic cancer is one of the leading causes of cancer deaths worldwide and constitutes a major public health problem. One of the most common symptoms associated with pancreatic adenocarcinoma is jaundice, caused by the obstruction of common bile duct. Endobiliary stenting is used to relief these patients either preoperatively or merely for palliation and plastic or metal stents are usually endoscopically or percutaneously placed. Two interesting studies were presented at the 2014 ASCO Gastrointestinal Cancers Symposium. Strom et al. sought to investigate the effect of preoperative biliary drainage on recurrence and survival and they concluded that percutaneous biliary decompression was an independent predictor of worse overall survival and was associated with non-significant increase in hepatic recurrence (Abstract #314). Montero et al. presented the results of their study regarding the cost-effectiveness of metal stents in patients with inoperable pancreatic cancer and they concluded that placement of metal biliary stents is cost saving, improves overall survival and qualityadjusted survival compared with plastic stents (Abstract #260). Both studies concluded to useful results that along with the existing literature and formulated guidelines may help the provision of more effective, higher quality management of these patients

Novel modalities in the treatment of patients with KRAS-mutated colorectal cancer

Mutations in the Kirsten rat sarcoma viral oncogene homolog (KRAS) gene are a well-described mechanism of resistance to monoclonal antibodies that target the epidermal growth factor receptor in patients with metastatic and nonoperable colorectal cancer. Treatment options in this population are limited to conventional chemotherapy regimens and antiangiogenesis compounds. Numerous strategies have been proposed in preclinical models as being effective in the presence of KRAS mutations. As basic and translational research further unravels the complex interactions and regulation points in the pathways downstream of epidermal growth factor receptor, more drugs become available for clinical testing. Indeed, there are many ongoing clinical trials that focus on the safety and efficacy of novel compounds in patients with KRAS-mutated colorectal cancer. This is a review of the literature with regard to the rationale of various approaches on this topic and also a summary of the current active clinical trials limited to patients with KRAS-mutated colorectal cancer. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins

Profile of capecitabine/temozolomide combination in the treatment of well-differentiated neuroendocrine tumors

Neuroendocrine tumors are a rare and heterogeneous group of tumors with a variety of primary origins and variable aggressiveness. Platinum-based chemotherapy has been the cornerstone of treatment for the poorly differentiated tumors. However, well-differentiated neuroendocrine tumors are quite chemoresistant and therapy options are limited. Octreotide analogs and tyrosine kinase inhibitors are widely acceptable treatments due to substantial efficacy and tolerable toxicity. On the contrary, monotherapy or combinations of the only approved cytotoxic agent streptozocin with other drugs have been almost abandoned because of excessive toxic events. In recent years, the combination of capecitabine and temozolomide has emerged as the most promising and efficacious treatment. The oral route of administration and the substantial improvement in the outcomes with manageable toxicity are the major advantages. We reviewed the current literature and presented the profile of the capecitabine/temozolomide combination in the management of well-differentiated neuroendocrine tumors. © 2016 Kotteas et al

Quality of life in patients with pancreatic cancer

QOL is highly affected in individuals suffering from pancreatic cancer. One parameter that influences negatively QOL in these patients is cancer -cachexia syndrome. During the ASCO Annual Meeting 2014, one abstract focusing on cancer-cachexia syndrome (Abstract #15208) emphasized the fact that cachexia is under diagnosed even in patients with pancreatic cancer who constitute a high-risk group for presenting this syndrome. In addition the abstract raises concerns about the benefit of the use of dronabinol and megestrol acetate in treating the cachexia syndrome in this group of patients. Another important factor that determines QOL in pancreatic cancer patients is surgical procedures-pancreatectomies that these patients may undergo. A very interesting abstract presented also at the ASCO Annual Meeting 2014 (Abstract #15234) explores the benefit of using pasireotide perioperative in ameliorating QOL of patients who had surgical intervention

Desmoplasia in pancreatic cancer. Can we fight it?

The hallmark of pancreatic tumours, the desmoplastic reaction, provides a unique microenvironment that affects pancreatic tumour behaviour, its ability to grow and metastasize as well as resist the effects of chemotherapy. Complex molecular interactions and pathways give rise to the desmoplastic reaction. Breakdown or penetration of the desmoplastic reaction may hold the key to overcoming the limits of delivery of efficacious chemotherapy or the development of new targeted treatments. Herein we discuss such new developments to fight the desmoplastic reaction, including inhibitors of the epidermal growth factor, fibroblast growth factor, the hedgehog pathway, as well as new molecular targets like CD40 agonist and its effects on T cells, extracellular matrix modifying enzymes such as LOXL2 inhibitor and novel tumour penetrating peptides for delivery of drugs. © 2012 E. E. Merika et al