Fabrication and characterization of chitosan nanoparticles and collagen-loaded polyurethane nanocomposite membrane coated with heparin for atrial septal defect (ASD) closure

Atrial septal defect (ASD) constitutes 30–40% of all congenital heart diseases in adults. The most common complications in the treatment of ASD are embolization of the device and thrombosis formation. In this research, an occluding patch was developed for ASD treatment using a well-known textile technology called electrospinning. For the first time, a cardiovascular occluding patch was fabricated using medical grade polyurethane (PU) loaded with bioactive agents namely chitosan nanoparticles (Cn) and collagen (Co) which is then coated with heparin (Hp). Fourier transform infrared spectrum showed characteristic vibrations of several active constituents and changes in the absorbance due to the inclusion of active ingredients in the patch. The contact angle analysis demonstrated no significant decrease in contact angle compared to the control and the composite patches. The structure of the electrospun nanocomposite (PUCnCoHp) was examined through scanning electron microscopy. A decrease in nanofiber diameter between control PU and PUCnCoHp nanocomposite was observed. Water uptake was found to be decreased for the PUCnCoHp nanocomposite against the control. The hemocompatibility properties of the PUCnCoHp ASD occluding patch was inferred through in vitro hemocompatibility tests like activated partial thromboplastin time (APTT), prothrombin time (PT) and hemolysis assay. It was found that the PT and APTT time was significantly prolonged for the fabricated PUCnCoHp ASD occluding patch compared to the control. Likewise, the hemolysis percentage was also decreased for the PUCnCoHp ASD patch against the control. In conclusion, the developed PUCnCoHp patch demonstrates potential properties to be used for ASD occlusion

A q-deformed nonlinear map

A scheme of q-deformation of nonlinear maps is introduced. As a specific example, a q-deformation procedure related to the Tsallis q-exponential function is applied to the logistic map. Compared to the canonical logistic map, the resulting family of q-logistic maps is shown to have a wider spectrum of interesting behaviours, including the co-existence of attractors -- a phenomenon rare in one dimensional maps.Comment: 17 pages, 19 figure

Fabrication and hemocompatibility assessment of novel polyurethane-based bio-nanofibrous dressing loaded with honey and Carica papaya extract for the management of burn injuries

Management of burn injury is an onerous clinical task since it requires continuous monitoring and extensive usage of specialized facilities. Despite rapid improvizations and investments in burn management, >30% of victims hospitalized each year face severe morbidity and mortality. Excessive loss of body fluids, accumulation of exudate, and the development of septic shock are reported to be the main reasons for morbidity in burn victims. To assist burn wound management, a novel polyurethane (PU)-based bio-nanofibrous dressing loaded with honey (HN) and Carica papaya (PA) fruit extract was fabricated using a one-step electrospinning technique. The developed dressing material had a mean fiber diameter of 190±19.93 nm with pore sizes of 4-50 µm to support effective infiltration of nutrients and gas exchange. The successful blending of HN- and PA-based active biomolecules in PU was inferred through changes in surface chemistry. The blend subsequently increased the wettability (14%) and surface energy (24%) of the novel dressing. Ultimately, the presence of hydrophilic biomolecules and high porosity enhanced the water absorption ability of the PU-HN-PA nanofiber samples to 761.67% from 285.13% in PU. Furthermore, the ability of the bio-nanofibrous dressing to support specific protein adsorption (45%), delay thrombus formation, and reduce hemolysis demonstrated its nontoxic and compatible nature with the host tissues. In summary, the excellent physicochemical and hemocompatible properties of the developed PU-HN-PA dressing exhibit its potential in reducing the clinical complications associated with the treatment of burn injuries

Surface, thermal and hemocompatible properties of novel single stage electrospun nanocomposites comprising polyurethane blended with bio oil™

In this work, the physicochemical and blood compatibility properties of prepared PU/Bio oil nanocomposites were investigated. Scanning electron microscope (SEM) studies revealed the reduction of mean fiber diameter (709 ± 211 nm) compared to the pristine PU (969 nm ± 217 nm). Fourier transform infrared spectroscopy (FTIR) analysis exposed the characteristic peaks of pristine PU. Composite peak intensities were decreased insinuating the interaction of the bio oil™ with the PU. Contact angle analysis portrayed the hydrophobic nature of the fabricated patch compared to pristine PU. Thermal gravimetric analysis (TGA) depicted the better thermal stability of the novel nanocomposite patch and its different thermal behavior in contrast with the pristine PU. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness of the composite patch. Activated partial thromboplastin time (APTT) and prothrombin time (PT) signified the novel nanocomposite patch ability in reducing the thrombogenicity and promoting the anticoagulant nature. Finally the hemolytic percentage of the fabricated composite was in the acceptable range revealing its safety and compatibility with the red blood cells. To reinstate, the fabricated patch renders promising physicochemical and blood compatible nature making it a new putative candidate for wound healing application

Gallic acid induced apoptotic events in HCT-15 colon cancer cells

AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid (GA) against HCT-15 colon cancer cells. METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide (MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species (ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2',7'-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1. RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase (0.98 ± 1.03 vs 58.01 ± 2.05) with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment. CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells

Detection of avian metapneumovirus field infection via reverse transcriptase polymerase chain reaction (RT-PCR) and ELISA in two layer farms in Johore

Avian metapneumovirus (AMPV) infection which is known as 'swollen head syndrome' has been shown to be prevalent in poultry farms in Malaysia. Two layer farms in Johor denoted as Farm A and Farm B, with previous history of AMPV disease outbreak, were the subjects used for the AMPV field investigation in this study. Thirty chicks from respective treatment groups were monitored at day old, two, four and six weeks of age for AMPV antibody and antigen detection. RT-PCR and ELISA serology indicate that at 2 weeks of age. AMPV field infection had occured in Farm A. In Farm B, AMPV field infection or lateral spread of vaccine was observed as early as 2 weeks. AMPV seroconversion was generally observed at four weeks of age and AMPV subtypes A and B were detected via RT-PCR from both farms in this study. This is the first report of AMPV subtypes A and B by RT-PCR detection in Malaysia

Survey of campylobacter, salmonella and mycoplasmas in house crows (Corvus splendens) in Malaysia

House crows (Corvus splendens) in Selangor, Malaysia were examined for the presence of Campylobacter species, Salmonella species, Mycoplasma gallisepticum and Mycoplasma synoviae by serology, culture and pcr. For the detection of Campylobacter and Salmonella species swabs were taken either from the intestine or cloaca. For the detection of mycoplasmas, swabs were taken either from the choanal cleft or trachea for culture and pcr and serum samples were tested by the rapid serum agglutination (rsa) and monoclonal antibody-blocking elisa (mbelisa) for antibodies to M gallisepticum and M synoviae. For campylobacter, 25·3 per cent of the crows were positive by culture, and the species identified were Campylobacter jejuni and Campylobacter coli. No Salmonella species were isolated. Four of 24 swabs were positive for M gallisepticum dna but none gave positive results for M synoviae dna. No M gallisepticum or M synoviae antibodies were detected by rsa but 60 per cent of the sera gave positive reactions for M gallisepticum and 13 per cent gave positive reactions for M synoviae by mbelisa

Prioritization of candidate genes in "QTL-hotspot" region for drought tolerance in chickpea (Cicer arietinum L.)

A combination of two approaches, namely QTL analysis and gene enrichment analysis were used to identify candidate genes in the "QTL-hotspot" region for drought tolerance present on the Ca4 pseudomolecule in chickpea. In the first approach, a high-density bin map was developed using 53,223 single nucleotide polymorphisms (SNPs) identified in the recombinant inbred line (RIL) population of ICC 4958 (drought tolerant) and ICC 1882 (drought sensitive) cross. QTL analysis using recombination bins as markers along with the phenotyping data for 17 drought tolerance related traits obtained over 1-5 seasons and 1-5 locations split the "QTL-hotspot" region into two subregions namely "QTL-hotspot_a" (15 genes) and "QTL-hotspot_b" (11 genes). In the second approach, gene enrichment analysis using significant marker trait associations based on SNPs from the Ca4 pseudomolecule with the above mentioned phenotyping data, and the candidate genes from the refined "QTL-hotspot" region showed enrichment for 23 genes. Twelve genes were found common in both approaches. Functional validation using quantitative real-time PCR (qRT-PCR) indicated four promising candidate genes having functional implications on the effect of "QTL-hotspot" for drought tolerance in chickpea.Sandip M Kale, Deepa Jaganathan, Pradeep Ruperao, Charles Chen, Ramu Punna, Himabindu Kudapa, Mahendar Thudi, Manish Roorkiwal, Mohan AVSK Katta, Dadakhalandar Doddamani, Vanika Garg, P B Kavi Kishor, Pooran M Gaur, Henry T Nguyen, Jacqueline Batley, David Edwards, Tim Sutton and Rajeev K Varshne

Effects of Intravenous Ephedrine on Onset Time and Intubating Conditions of Rocuronium Bromide

INTRODUCTION: The introduction of d-tubocurarine - a neuromuscular blocking drug, by Griffith and Johnson1 in 1942 revolutionized clinical anaesthesia. The use of muscle relaxants became a vitally important aspect of modern anaesthesia practice. In 1967, Baird and Reid first reported on the clinical administration of the synthetic amino steroid pancuronium. Development of the intermediate acting neuromuscular blockers was built on compound metabolism and resulted in the introduction of vecuronium, an aminosteroid,and atracurium, a benzylisoquinolium, in the 1980s. The lack of cardiovascular effects of vecuronium and degradation of atracurium by Hoffmann elimination, reduced the effects of biologic disorders such as advanced age or organ failure on the pattern of neuromuscular blockade. Despite the above mentioned neuromuscular blocking drugs, succinylcholine still remains the favorite for achieving rapid, evanescent relaxation despite its dangers of triggering malignant hyperthermia, producing hyperkalemia in susceptible patients, raising intra ocular pressure, raising intra cranial pressure and muscle pains in many. Although succinylcholine is a reliable agent due to its rapid onset, its numerous side effects led to the search of newer muscle relaxants with a similar onset of action. The technique of administering established non depolarizing muscle relaxants has been variously modified in an attempt to reduce its onset time. Rocuronium is the first non-depolarizing relaxant considered to be an acceptable substitute for succinylcholine in facilitating rapid tracheal intubation. Ephedrine is a sympathomimetic drug which acts on alpha1 and beta receptors. It acts as agonist at these receptors and increases cardiac output and muscle blood flow. It increases the oxygen consumption of tissues but cardiac output is also increased to meet the demand. The onset time of muscle relaxants is partly determined by the speed with which these drugs reach the neuromuscular junction. This concept is used in the present study in which the effect of Intravenous Ephedrine on the onset time and Intubating conditions of Rocuronium bromide was studied. AIM OF THE STUDY: To compare the Effect of intravenous “Ephedrine” on the onset of action of Rocuronium and intubating conditions with a “placebo”. MATERIALS AND METHODS It was a prospective, Randomized, Double blinded(subject), Case control study conducted in the Institute of Anaesthesiology and Critical Care, Madras medical college and Government General Hospital, Chennai Inclusion Criteria: 1. Males And Females. 2. ASA Physical Status 1,2,3. 3. Age 15 Years and Older. 4. Elective Patients Given General Anesthesia. 5. Patient Who Had Given Informed Consent. Exclusion Criteria: 1. Not Satisfying Inclusion Criteria. 2. Emergency Surgeries Under GA. 3. Patients With Neuromuscular Disorders, Cardiovascular Disease. 4. Hepatic or Renal Disease 5. Patients with Difficult Airway. 6. Intake of Drugs Known to Interact with Meuromuscular Junction or Ephedrine. 7. Increased Risk Of Pulmonary Aspiration. MATERIALS: 1. Injection Ephedrine 70 Microgram/Kg. 2. Drugs – Fentanyl, Glycopyrrolate, Thiopentone, Xylocard, Rocuro Nium Bromide, Normal Saline, Emergency Drugs. 3. Macintosh Laryngoscope with 3, 4 Blades. 4. Endotracheal Tubes of Various Sizes. 5. Monitors‐ ECG, NIBP, SPO2, Neuromuscular Monitor. OBSERVATION AND RESULT: This prospective, randomized, single blind (subject), case controlled study compared the Effects of intravenous Ephedrine on the onset time of rocuronium bromide and intubating conditions measured by haemodynamic alterations and pogo score. Primary Outcome Measures: 1. Onset Time of Rocuronium After Test Drug And Placebo. Secondary Outcome Measures: Intubating Conditions Using : 1. Hemodynamic Variables, 2. Pogo Score and Cormack and Lehane Grading All Data were Collected and Tabulated. Demographic Variables: 60 patients were randomly selected and included in this study. Thirty patients were randomly assigned to receive PLACEBO of 5ml. saline (Group A) and thirty patients received the test drug of 70 microgram/kg EPHEDRINE (Group B). Mean age, sex distribution and weight of the patients in both the group were compared and there was no significant difference between the groups. SUMMARY: In our study, the effect of intravenous “Ephedrine” on the onset time and intubating conditions of rocuronium bromide was compared with “Placebo”. All the patients in Ephedrine group were pretreated with ephedrine 70microgram/kg prior to induction and rocuronium 0.6mg/kg was given . All the patients in “Placebo” group were given 5ml Saline prior to induction. Onset of action is determined by abolition T1 in TOF and absence of single twitch stimulation in Neuro muscular monitor. The onset of action of Rocuronium was significantly shorter in “Ephedrine”group when compared to “Placebo” group. Ephedrine group provided better intubating conditions when compared with Placebo group. There was no clinically significant difference between the two groups with respect to heart rate and blood pressure changes.There was no significant incidence of adverse effects in both groups. CONCLUSION: It may be concluded from this study that “Ephedrine given at the dose of 70microgram/kg significantly shortens the onset time of Rocuronium bromide and provides better intubating conditions with minimal haemodynamic changes”

NIOSOMES AS AN EMERGING FORMULATION TOOL FOR DRUG DELIVERY-A REVIEW

Nonionic surfactant based vesicles which are uni/multilamellar in structures are called niosomes. These vesicles contains an aqueous interior surrounded by one or more amphiphilic bilayer membrane forming surfactant which separates them from the bulk solution, and are also called as supramolecular aggregates. Niosomes, being an efficient drug delivery system, investigations are carried out to utilize this system to treat various disorders, to promote improved patient compliance, lesser side effects, reduction in dose, lesser dosage frequency, and higher amount of the drug at the particular site so as to lessen an excessive contact with the whole body. The Pharmacokinetic and Pharmacodynamic profile of Niosomal drug delivery system vary for various entrapped drugs. Drugs that are successful in the mitigation or treatment of CNS disorders should cross the BBB to reach the brain, as BBB seems to be an obstacle for a large number of drugs, including CNS active drugs. This article compiles recent techniques for the preparation and characterization of niosomes, the effect of formulation variables on its physicochemical properties and discussed about its effective applications in drug delivery