Frequency of Post Endoscopic Retrograde Cholangiopancreatography Acute Pancreatitis in an Academic Hospital of Bangladesh

Post-ERCP acute pancreatitis (PEP) is a common and serious complication with high morbidity and mortality rates. There is a paucity of data on the frequency of PEP in a resource constraint setting like Bangladesh. Hence we have conducted a prospective study to determine the frequency of PEP and the factors associated with its occurrence. This prospective, observational study was carried out in Gastroenterology Department of Dhaka Medical College & Hospital, Dhaka, Bangladesh from April 2018 to December 2018 on the consecutive patients who underwent ERCP. PEP and its severity were diagnosed according to consensus definition. Serum lipase was done in all patients before procedure and 24 hours after procedure or if patient develops abdominal pain after the procedure which became earlier. Total 168 patients were included (mean age 46.97±14.35 years; male 72(43.0%). The most common indication of ERCP was choledocholithiasis 97(58.0%) followed by malignant biliary obstruction 45(27.0%), recurrent pyogenic cholangitis 8(5.0%), chronic pancreatitis 4(2.3%), biliary ascariasis 4(2.3%) and others 10(6.0%). Overall post ERCP complication rate was 46(27.3%) including cholangitis 29(17.3%), pancreatitis 16(9.5%), bleeding 12(7.1%), aspiration pneumonia 4(2.4%) and death 3(1.8%). Regarding the severity of PEP, 50.0%, 43.7% and 6.3% patients developed mild, moderate and severe pancreatitis respectively. Number of cannulation attempts >5 times [22(48%) vs. 17(14%); p=0.001], cannulation attempts duration more than 10 minutes [25(55%) vs. 27(22%); p=0.001], unintentional passage of guide wire into the pancreatic duct [8(17%) vs. 18(15%); p=0.001], pancreatic duct contrast injection [12(26%) vs. 2(1.6%); p=0.001] and pre-cut sphincterotomy [16(35%) vs. 6(4.9%); p=0.001] were significantly different between the patients who developed PEP compared to those who did not. In multiple logistic regressions analysis, pancreatic duct contrast injection was significantly associated with PEP [OR 25.523 with 95% CI (4.049- 100.0%)]. Around ten percent patients had developed PEP. Regarding the severity half of them were mild, 44.0% patients had moderate and 6.0% patient had severe type of pancreatitis. Difficult cannulation, unintentional passage of guide wire into the pancreas, pancreatic duct contrast injection and pre-cut sphincterotomy were associated with PEP. Among them pancreatic duct contrast injection had independent significance in the causation of PEP.

Fusarium oxysporum; its enhanced entomopathogenic activity with acidic silver nanoparticles against Rhipicephalus microplus ticks

Fusarium oxysporum is an entomopathogenic fungus, and it has anti-biological activity against arthropods. Ticks are blood sucking arthropods which are responsible for transmitting different diseases in humans and animals. The use of chemical insecticides against ticks is not eco-friendly option and results in the development of acaricide resistance. Previously, we had cultured a local isolate of Fusarium oxysporum from soil samples which were identified through microscopy and confirmed through molecular technique. In our previous experiments, we have prepared Silver nanoparticles (AgNP) at pH 7 and they had been characterized through X-Ray Diffraction (XRD), UV-visible and zeta-potential. In our current study, the AgNP were prepared at different pH conditions and characterized through Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The protein molecules of F. oxysporum were charged with Ag ions. F. oxysporum NP were observed to enhance anti-biological activity by killing Rhipicephalus microplus and they caused 100% mortality at pH 4 and pH 5 in 24 h in anti-tick biological assay. Our study is the first report to do biological assay against Rhipicehalus ticks by using Fusarium AgNP at acidic pH. Biological control using entomopathogenic fungi can be the best alternative of the chemical method to control the tick population.

Copper doping enhanced the oxidative stress-mediated cytotoxicity of TiO2 nanoparticles in A549 cells

Physicochemical properties of titanium dioxide nanoparticles (TiO₂ NPs) can be tuned by doping with metals or nonmetals. Copper (Cu) doping improved the photocatalytic behavior of TiO₂ NPs that can be applied in various fields such as environmental remediation and nanomedicine. However, interaction of Cu-doped TiO₂ NPs with human cells is scarce. This study was designed to explore the role of Cu doping in cytotoxic response of TiO₂ NPs in human lung epithelial (A549) cells. Characterization data demonstrated the presence of both TiO₂ and Cu in Cu-doped TiO₂ NPs with high-quality lattice fringes without any distortion. The size of Cu-doped TiO₂ NPs (24 nm) was lower than pure TiO₂ NPs (30 nm). Biological results showed that both pure and Cu-doped TiO₂ NPs induced cytotoxicity and oxidative stress in a dose-dependent manner. Low mitochondrial membrane potential and higher caspase-3 enzyme (apoptotic markers) activity were also observed in A549 cells exposed to pure and Cu-doped TiO₂ NPs. We further observed that cytotoxicity caused by Cu-doped TiO₂ NPs was higher than pure TiO₂ NPs. Moreover, antioxidant N-acetyl cysteine effectively prevented the reactive oxygen species generation, glutathione depletion, and cell viability reduction caused by Cu-doped TiO₂ NPs. This is the first report showing that Cu-doped TiO₂ NPs induced cytotoxicity and oxidative stress in A549 cells. This study warranted further research to explore the role of Cu doping in toxicity mechanisms of TiO₂ NPs.

Application of polyhydroxyalkanoates for denitrification in water and wastewater treatment

Application of polyhydroxyalkanoates (PHAs) and related biodegradable polymers has gained momentum in various areas of biotechnology. A promising application that started appearing in the past decade is the use of PHAs as the solid substrate for denitrification of water and wastewater. This type of denitrification, termed here "solid-phase denitrification", has several advantages over the conventional system supplemented with liquid organic substrate. PHAs serve not only as constant sources of reducing power for denitrification but also as solid matrices favorable for development of microbial films. In addition, in contrast to conventional processes, the use of PHAs has no potential risk of release of dissolved organic carbon with the resultant deterioration of effluent water quality. If the production cost of PHAs can be brought down, its application to the denitrification process will become economically more promising. A number of PHA-degrading denitrifying bacteria have been isolated and characterized from activated sludge and continuous flow-bed reactors for denitrification with PHAs. Most of these isolates have been assigned phylogenetically to members of beta-Proteobacteria, especially those of the family Comamonadaceae. The metabolic and regulatory relationships between PHA degradation and denitrification, and the interactive relationship between PHA-degrading cells and the solid surface structure are important subjects awaiting future studies, which would provide a new insight into our comprehensive understanding of the solid-phase denitrification process.