In-vivo Trials Research Articles

Abstract No. 514 Injectable thermo-sensitive hydrogels as chemoembolic drug delivery agents for interventional applications

Controversy exist when discussing disease control of hepatocellular carcinoma in regards to bland embolization verses drug loaded microspheres. While the reasons for the absence of convincing data supporting the use of embolic microspheres in combination with chemotherapy are multiple, the importance of achieving complete vascular occlusion and sustained drug release are clear. Therefore, the development of biodegradable injectable drug loaded materials that can “cast” the tumor capillary bed would be advantageous. Chitosan is an FDA approved biocompatible and biodegradable polysaccharide derived from the crustacean exoskeleton. It can be used as a delivery vehicle for small molecules. Chitosan was dissolved in 0.25% acetic acid solution (1.44%w/v) under magnetic stirring for approximately 12 hours at room temperature. The solution was sterilized by autoclaving at 121ºC for 30 min. Chitosan (5 mL) was mixed with 200μL of ammonium hydrogen phosphate (AHP) solution (60% aqueous solution) via two syringe vigorous mixing method. The pH of the mixture was in the range of 7-7.2. Doxorubicin (5 mg/ml) was loaded into chitosan solution during magnetic stirring for release studies. The drug released from the hydrogel was determined by measuring the concentrations of the doxorubicin after set time points with a UV-vis spectrophotometer at 483 nm with a standard curve constructed with known concentrations of doxorubicin. The resulting solution can be injected through a microcatheter with gelation times range from 1-3 minutes at 37 degrees. In vitro degradation and release studies were performed with doxorubin from the hydrogel. It was determined that the hydrogels are stable in an aqueous environment for up to 90 days. Additionally, when loaded with 5 mg/ml doxorubicin, drug release profiles demonstrated up to 70% delivery of the drug at 28 days. We hypothesized that the development of a chitosan hydrogel to enable casting and drug release can be used as an intravascular chemoembolic agent. These gels demonstrate controlled, sustained release of doxorubicin and can be injected through a microcatheter in preparation for in-vivo trials.

Influences of quorum-quenching probiotic bacteria on the gut microbial community and immune function in weaning pigs.

The aim of this study is to investigate the dynamic gut microbial diversity in weaning swine after administering feed supplemented with probiotic bacteria that specifically inhibit the activity of quorum molecules. Initially, the universal quorum molecule autoinducer-2 (AI-2) bioassay results indicated that AI-2 activity was profoundly inhibited in enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the presence of Lactobacillus acidophilus strain 30SC cell extract, although the growth of EHEC was not affected. Based on plate counting results, bacterial community analysis revealed a specific reduction in coliforms compared to the control, whereas the population of lactobacilli increased in weaning swine in invivo trials. Supplementation with L.acidophilus strain 30SC did not affect the counts of other communities, such as total aerobes and yeast/mold. In addition, PCR-denaturing gradient gel electrophoresis analysis showed a significant difference in the 16S rRNA gene products after administering L.acidophilus strain 30SC. Selected bands were sequenced, and most of them were identified as uncultured bacterium clones or a Lactobacillus- and Bifidobacterium-specific community. Therefore, our results indicate that quorum-quenching probiotic bacteria can significantly modulate the gut microbiota of swine and these beneficial effects can contribute to the improvement of performance and health in the gastrointestinal tract of weaning pigs.

DFT predictions, synthesis, stoichiometric structures and anti-diabetic activity of Cu (II) and Fe (III) complexes of quercetin, morin, and primuletin

The current study is aimed at the synthesis of Cu (II) and Fe (III) complexes of three flavonoids {morin (mor), quercetin (quer) and primuletin (prim)} and characterization through UV–Vis spectroscopy, cyclic voltammetry, FTIR, and thermal analysis. Structure prediction through DFT calculation was supported by experimental data. Benesi-Hildebrand equation was modified to function for 1:2 Cu-flavonoid and 1:3 Fe-flavonoid complexes. DFT predictions revealed that out of poly chelation sites present in morin and quercetin, 3-OH site was utilized as preferable chelation site while primuletin chelated through 5-OH position. In-vivo trials revealed the complexes to have better anti-diabetic potential than respective flavonoid. Fls/M-Fls proved as antagonistic to Alloxan induced diabetes and also retained anti-diabetic activity even in the presence of (2-hydroxypropyl)-β-cyclodextrin (HPβCD).

In-vitro validation of a closed-loop optogenetic stimulation device.

Closed-loop optogenetic stimulation (CLOS) involves real-time neural data collection and analysis, feedback control, and optical neuromodulation. Despite emergence of the CLOS devices, methods for validating such devices in-vitro are limited. This paper presents a CLOS device and introduces an in-vitro setup for validating CLOS devices. The CLOS device consists of an electrode, a neural detector, a control algorithm, and an optogenetic stimulator. The in-vitro setup consists of saline solution, a neural signal emitter, a photodiode and its amplifier, and a closed-loop simulation program. Synthetic neural signals are delivered to the CLOS device, and based on the sensed optical stimulations from the light source, the properties of the delivered neural signals are changed. Experiments are conducted to evaluate the closed-loop operation of the CLOS device, and verify the capability of the in-vitro setup to for validating the CLOS devices. The in-vitro setup enables refinement of CLOS devices before arduous in-vivo trials.

Study on the quality and stability of minimally processed apples impregnated with green tea polyphenols during storage

Abstract In the present study, a green tea extract (GTE) was used to enrich minimally processed apples by vacuum impregnation VI in order to obtain a nutritionally fortified product. Apples were impregnated with isotonic sucrose solutions containing 1% GTE and/or 1% ascorbic acid (AA). The impact of GTE enrichment on quality characteristics of the product, stability of the antioxidant compounds and activity during refrigerated storage were assessed. Results showed that a satisfactory impregnation of minimally processed apples was achieved and resulted in a strong increase of the antioxidant compounds content and activity. While other qualitative parameters were only slightly affected, colour of samples was influenced just after the VI treatment with an increase of the yellow/orange colour components but also during storage with a higher degree of browning development. However, the addition of 1% of AA allowed to better preserve colour and antioxidant properties during storage limiting oxidative phenomena. Industrial relevance The demand for functional foods characterized by a high nutritional value is constantly increasing. Vacuum impregnation (VI) is a technology that allows the replacement of the gas into the porous food structure with an aqueous solution, promoting compositional changes in short treatment times thus permitting the direct formulation of a porous food matrix, hence representing a promising technology for product innovation for the fruit and vegetable industry. Green tea (GT) is a high source of flavanoids, known to have strong antioxidant properties which has been widely studied both in in-vitro and in-vivo trials. According to the results obtained in this study, the enrichment of apples with GT catechins and AA seemed to be promising in order to obtain a nutritionally fortified fruit product.

Isolation, Characterization, and Antibacterial Activity of Bacteriophages Against Methicillin-Resistant Staphylococcus aureus in Pakistan.

BackgroundIn recent years, antibiotic resistance has been indicated as a paramount threat to public health. The use of bacteriophages appears to be a safer alternative for the control of bacterial infections.ObjectivesThe present study aims to explore sewage water for the presence of indigenous bacteriophages, and to investigate their antibacterial potential against Methicillin-resistant Staphylococcus aureus (MRSA).MethodsBacterial isolates were first collected and identified from pus samples taken from the surgical and burn units using standard microbiological procedures. A cefoxitin disk screen test was then used and interpreted according to the clinical laboratory standards institute (CLSI) guidelines for the detection of MRSA. The sewage samples were processed and the phages enriched using S. aureus as a host organism. Turbid and clear plaques of different sizes were isolated using an overlay method, purified, and then enumerated by means of a dilution method.ResultsThe phages exhibited good lytic activity against MRSA when tested in-vitro, and the highest activity was attained within three to six hours of phage infection. The isolated phage pq/48 was also found efficient in decreasing the bacterial count during an in-vivo trial in rabbits. A protein analysis using SDS-PAGE revealed 10 proteins of between 20 kDa and 155 kDa in size.ConclusionsThe overall results indicated that bacteriophages isolated from sewage exhibited excellent lytic activity against MRSA strains. In conclusion, bacteriophages can be further characterized and appear to be a promising candidate for phage therapy against MRSA in the future.

Feasibility of electromagnetically guided transjugular intrahepatic portosystemic shunt procedure

Objectives: To develop an electromagnetic navigation technology for transjugular intrahepatic portosystemic shunt (TIPS) creation and translate it from phantom to an in-vivo large animal setting.Material and methods: A custom-designed device for TIPS creation consisting of a stylet within a 5 French catheter as well as a software prototype were developed that allow real-time tip tracking of both stylet and catheter using an electromagnetic tracking system. Feasibility of navigated TIPSS creation was tested in a phantom by two interventional radiologists (A/B) followed by in-vivo testing evaluation in eight domestic pigs. Procedure duration and number of attempts needed for puncture of the portal vein were recorded.Results: In the phantom setting, intervention time to gain access to the portal vein (PV) was 144 ± 67 s (A) and 122 ± 51 s (B), respectively. In the in-vivo trials, TIPS could be successfully completed in five out of eight animals. Mean time for the complete TIPS was 245 ± 205 minutes with a notable learning curve towards the last animal.Conclusions: TIPS creation with the use of electromagnetic tracking technology proved to be feasible in-vitro as well as in-vivo. The system may be useful to facilitate challenging TIPSS procedures.

Minimum length of the adaptation and collection period in digestibility trials with sheep fed adlibitum only forage or forage plus concentrate.

Two invivo digestibility trials with sheep were conducted to identify the minimum period length of feeding a new diet to obtain reproducible values of nutritional variables onward and the minimum length of collection period as to obtain maximal precision for each variable. Trial 1 was conducted with ten Polwarth male sheep (34±5kg body weight (BW)) throughout three 21-day periods, in a completely randomized two-way crossover design. The animals were divided into two groups (Group A and B, n=5 per group) which were fed adlibitum with a sequence of the following diets throughout the periods: Group A: hay - hay plus concentrate - hay; Group B: hay plus concentrate - hay - hay plus concentrate. The concentrate was included in a proportion of 0.33 of the total diet. The intake, and the faecal and urinary excretion were measured daily throughout the experiment. For evaluating rumen fermentation variables, in Trial 2 four Santa Inês male sheep (65±5kg BW) fitted with ruminal cannula were used. The animals were randomly divided into two groups (n=2 per group), and the trial was conducted through four 21days experimental period, in a three-way crossover design, using experimental diets and feeding management similar to Trial 1. The results indicated that, even though no clear or consistent steady-state condition was identified for rumen fermentation or urinary excretion variables, the adaptation period for measuring OM digestibility in invivo trials with sheep fed adlibitum where the diet shifts from one of only hay to another containing concentrate, or vice-versa, should be at least 12days long. Moreover, although no precision improvement was obtained by increasing the collection period above 1day for measuring OM digestibility, the minimal length of collection period should be 4days for measuring faecal excretion variables and 7days for measuring urinary excretion variables.

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Morinda citrifolia L. is commonly known as Noni and has been found to have wide range of medicinal properties. It is usually found in the coastal region in many countries including Andaman and Nicobar Islands and belongs to the family Rubiaceae. This small evergreen tree is widely grown and well adapted to the tropics and can grow in fertile, acidic, alkaline and saline affected soils. It tolerates high soil salinity and brackish water stagnation. All the components of this plant have high demand in case of alternative medicines and herbal medicines. Due to its high demand and as a source of revenue generation the detail study on its nutritional benefits and therapeutic values are essential for its commercial exploitation. More than 200 nutraceutical compounds have been identified from the plant. Morinda citrifolia is reported to have broad spectrum biological activities such as antimicrobial, immunomodualtory, antioxidant wound healing etc. Apart from the in-vitro scientific validation of the activities and in-vivo trial in some lab animal model, the plant has been used for livestock and poultry health and production. A lot of reviews have been written on the different uses of Noni, however, scientific review on the use of this plant on the growth, production, immunomodulator and other pharmacological activities of M. citrifolia in livestock and poultry has not been compiled. Therefore this review discusses the compilation of the work done on the use of M. citrifolia in livestock and poultry. Jai Sunder*, Tamilvannan Sujatha and Anandamoy Kundu

In-vitro and in-vivo biological activity of recombinant yellowtail kingfish (Seriola lalandi) follicle stimulating hormone

Biologically active recombinant yellowtail kingfish follicle stimulating hormone (rytkFsh) was produced in yeast Pichia pastoris and its biological activity was demonstrated by both in-vitro and in-vivo bioassays. Incubation of ovarian and testicular fragments with the recombinant hormone stimulated E2 and 11-KT secretion, respectively. In-vivo trial in immature female YTK resulted in a significant increase of plasma E2 levels and development of oocytes. In males at the early stages of puberty, advancement of spermatogenesis was observed, however plasma 11-KT levels were reduced when administered with rytkFsh.

Efficacy of biotechnologically derived product in counteracting ill effects of aflatoxins in broiler chicken

A preliminary in-vitro aflatoxin adsorption study was conducted, and it was found that, the degradability of aflatoxin (AF) by the biotechnologically derived product (BTP) was similar to that of hydrated sodium calcium allumino-sillicate (HSCAS) and mannan ologosachharide (MOS). Further, an in-vivo trial was undertaken to assess BTP over HSCAS in broiler chicken fed diet containing aflatoxin (AF) with experimental design: T1-basal diet; T2-250 ppb of AF; T3-AF 250 ppb with HSCAS at 1 kg/ton; T4 and T5-AF 250 ppb with BTP 200 g/ton and 400 g/ton, respectively. During 42 days, trial revealed non-significant differences in performance parameters, dressing percentage, relative organ weights and serum biochemical parameters among treatments. Whereas, serum profile of ALT (P<0.01) and AST (P<0.05) was significantly increased with addition of AF (T2) indicating limitation of toxicity only to cellular level at liver. Addition of BTP was found to normalize the increased ALT and AST levels.

Arterial compliance probe for local blood pulse wave velocity measurement.

Arterial compliance and vessel wall dynamics are significant in vascular diagnosis. We present the design of arterial compliance probes for measurement of local pulse wave velocity (PWV). Two designs of compliance probe are discussed, viz (a) a magnetic plethysmograph (MPG) based probe, and (b) a photoplethysmograph (PPG) based probe. The ability of the local PWV probes to consistently capture carotid blood pulse waves is verified by in-vivo trials on few volunteers. The probes could reliably perform repeatable measurements of local PWV from carotid artery along small artery sections less than 20 mm. Further, correlation between the measured values of local PWV using probes and various measures of blood pressure (BP) was also investigated. The study indicates that such arterial compliance probes have strong potential in cuff less BP monitoring.

Production of a wheat-based fermented rice enriched with γ-amino butyric acid using Lactobacillus plantarum MNZ and its antihypertensive effects in spontaneously hypertensive rats

This study aimed to develop and characterize a wheat-based fermented rice (dosa) with potential anti-hypertensive effects using γ-aminobutyric acid (GABA)-producing Lactobacillus plantarum. Results showed that lactic acid bacterial fermentation enhanced the angiotensin converting enzyme inhibitory, radical scavenging activities and the GABA content (143 mg/kg at 120 h fermentation) of the dosa. The rats in the in-vivo trial were fed experimental diets containing dosa (T1), fermented dosa (T2) or dosa + pure GABA (T3). The systolic blood pressure, aortic endoteline-1 protein, plasma norepinephrine, serum level of thiobarbituric acid reactive substances and superoxide dismutase activity indicated improvement upon feeding of the diets containing GABA. While, the blood chemistry variables were not significantly affected in this experiment. GABA-enriched fermented dosa could therefore be considered as a functional food with the promising blood-pressure lowering effect.

Artificial Pancreas: from in-silico to in-vivo

Type 1 diabetes is a disease caused by an autoimmune reaction. The Artificial Pancreas (AP) is an automatic closed-loop system composed of a subcutaneous glucose sensor, a subcutaneous insulin pump and a device on which a control algorithm and a human interface are implemented. The last years have seen an accelerated improvement of these three components that became more reliable and compact, making the system safer, wearable, and usable in real life. An overview on AP and its components is presented together with an introduction on the in-silico tools used to develop and tune the control algorithm and to make pre-clinical tests. Particular attention is devoted to the design of a Model Predictive Control, to the choice of the model and of the constraints, and to the definition of the most relevant performance indices. Most of the choices have been driven by the experience gained by both in-silico and in-vivo trials. In-silico experiments involved thousand of hours of simulations on the Food and Drug Administration accepted simulator equipped with 100 adult virtual patients. In-vivo experiments, of which a complete list is presented, involved about forty thousand hours of trials, first, conducted in a clinical environment and, then, at home.

Preliminary clinical trials of karela, Momordica charantia, on non-insulin-dependent diabetes mellitus patients

Background Traditional methods of treatment for diabetes was recommended by WHO in 1985. On in-vivo trials in animal models, one of the authors revealed the potentiality of karela in the treatment of diabetes. Aim The aim of the study was to evaluate the effects of Momordica charantia as a hypoglycemic in type 2 diabetic patients. Formulated tablets from M . charantia (karela) juice of the unripe fruits were used. Materials and methods Juice from immature fruits was filtrated through specific membranes to separate active polypeptide mimic insulin. The powder obtained after spray drying was formulated as a 20 mg tablet of polypeptide. Eighteen of 60 patients continued the treatment. All patients had type 2 diabetes. They were followed up for 1-8 weeks and examined clinically and investigated for different parameters. Results As this trial is a case analysis, the result of each case was presented and the overall trial results were discussed. Conclusion M. charantia can be used as an effective oral adjunct hypoglycemic, with no reportable clinical side effects. The treatment must be continued for 4 weeks.

Ophthalmic halo reduced lenses design

The halo effect is a very problematic visual artifact occurring in extended depth of focus or multi-focal ophthalmic lenses such as e.g. intra-ocular (after cataract surgery) or contact lenses when used in dark illumination conditions. This artifact is generated due to surface structures added on top of those lenses in order to increase their depth of focus or to realize multiple focal lengths. In this paper we present novel solution that can resolve this major problem of ophthalmic lenses. The proposed solution involves modification to the surface structure that realizes the extended depth of focus. Our solution is fabricated and numerically and experimentally validated also in preliminary in-vivo trials.

Design of a lossless image compression system for video capsule endoscopy and its performance in in-vivo trials.

In this paper, a new low complexity and lossless image compression system for capsule endoscopy (CE) is presented. The compressor consists of a low-cost YEF color space converter and variable-length predictive with a combination of Golomb-Rice and unary encoding. All these components have been heavily optimized for low-power and low-cost and lossless in nature. As a result, the entire compression system does not incur any loss of image information. Unlike transform based algorithms, the compressor can be interfaced with commercial image sensors which send pixel data in raster-scan fashion that eliminates the need of having large buffer memory. The compression algorithm is capable to work with white light imaging (WLI) and narrow band imaging (NBI) with average compression ratio of 78% and 84% respectively. Finally, a complete capsule endoscopy system is developed on a single, low-power, 65-nm field programmable gate arrays (FPGA) chip. The prototype is developed using circular PCBs having a diameter of 16 mm. Several in-vivo and ex-vivo trials using pig's intestine have been conducted using the prototype to validate the performance of the proposed lossless compression algorithm. The results show that, compared with all other existing works, the proposed algorithm offers a solution to wireless capsule endoscopy with lossless and yet acceptable level of compression.

Magnetic plethysmograph transducers for local blood pulse wave velocity measurement.

We present the design of magnetic plethysmograph (MPG) transducers for detection of blood pulse waveform and evaluation of local pulse wave velocity (PWV), for potential use in cuffless blood pressure (BP) monitoring. The sensors utilize a Hall effect magnetic field sensor to capture the blood pulse waveform. A strap based design is performed to enable reliable capture of large number of cardiac cycles with relative ease. The ability of the transducer to consistently detect the blood pulse is verified by in-vivo trials on few volunteers. A duality of such transducers is utilized to capture the local PWV at the carotid artery. The pulse transit time (PTT) between the two detected pulse waveforms, measured along a small section of the carotid artery, was evaluated using automated algorithms to ensure consistency of measurements. The correlation between the measured values of local PWV and BP was also investigated. The developed transducers provide a reliable, easy modality for detecting pulse waveform on superficial arteries. Such transducers, used for measurement of local PWV, could potentially be utilized for cuffless, continuous evaluation of BP at various superficial arterial sites.

Microbiological studies on genital infections in slaughtered ewes from tropical arid zone of Nigeria

An abattoir survey was undertaken to investigate genital bacterial infections of ewes in tropical arid zone of Nigeria. Vaginal and uterine samples were collected and cultured using standard bacteriological techniques. The results of the study showed that the isolates were Escherichia coli (32%), Staphylococcus spp (26%), Klebsiella spp (16%), Pseudomonas (15%) and Proteus (11%); wherein E coli and S aureus were the most common bacterial isolates. The bacterial population in the vagina (64%) was significantly (p<0.05) higher than that in the uterus (34%). The antibiotic susceptibility test revealed that E. coli was highly susceptible (100%) to Amoxycillin, Ampicillin, Amoxycillin-clavulanate and Pefloxacin, whereas low susceptibility was observed against Ciprofloxacin and Ofloxacin (10 and 22% respectively). S. aureus showed 100% susceptibility to Amoxycillin-clavulanate, Gentamicin, Nalidixic acid and Pefloxacin, whereas susceptibility against Streptomycin, Amoxycillin, Ciprofloxacin and Ofloxacin was in declining order (46, 33, 30 and 20% respectively). The potentials of these microbes for producing pathogenicity in genital tract of ewes is likely to be high in Nigeria. Therapeutic use of these antimicrobial agents will help to reduce infectious reproductive diseases in ewes, though in-vivo trials are further required for establishing their efficacy in controlling genital infections in ruminants.Keywords: Antimicrobial susceptibility, Ewes, E. coli, S. aureus, Genital infections

Simulation of clinical fractures for three different all‐ceramic crowns

Comparison of fracture strength and fracture modes of different all-ceramic crown systems is not straightforward. Established methods for reliable testing of all-ceramic crowns are not currently available. Published in-vitro tests rarely simulate clinical failure modes and are therefore unsuited to distinguish between the materials. The in-vivo trials usually lack assessment of failure modes. Fractographic analyses show that clinical crowns usually fail from cracks initiating in the cervical margins, whereas in-vitro specimens fail from contact damage at the occlusal loading point. The aim of this study was to compare three all-ceramic systems using a clinically relevant test method that is able to simulate clinical failure modes. Ten incisor crowns of three types of all-ceramic systems were exposed to soft loading until fracture. The initiation and propagation of cracks in these crowns were compared with those of a reference group of crowns that failed during clinical use. All crowns fractured in a manner similar to fracture of the clinical reference crowns. The zirconia crowns fractured at statistically significantly higher loads than alumina and glass-ceramic crowns. Fracture initiation was in the core material, cervically in the approximal areas.