Vial Method Research Articles

Rapid test to detect insecticide resistance in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae).

Introduction: The development of insecticide resistance in Spodoptera frugiperda populations is a serious threat to the crop industry. Given the spread of invasive resistant populations, prospective monitoring should be accelerated, and the development of diagnostic tools for rapid and accurate assessments of insecticide resistance is essential. Methods: First, the discriminating dose and diagnostic time of the kit were determined by the glass vial method based on a susceptible strain. Then, pests that were collected from field populations were used to determine their susceptibility to seven insecticides by using the diagnostic kit. Finally, the accuracy of the kit was verified based on correlation analyses and the likelihood of insecticide control failure was assessed. Results: Here, we describe a diagnostic kit that enables the rapid detection of resistance to chlorpyrifos, bifenthrin, deltamethrin, lambda-cyhalothrin, phoxim, chlorantraniliprole and chlorfenapyr within 1-2h in S. frugiperda at diagnostic doses of 0.98, 0.84, 0.38, 1.64, 0.0082, 1.75 and 0.65μg/cm2, respectively. The linear equation between mortalities under diagnostic doses and actual resistance ratios measured by the diet-overlay bioassay was determined. The high correlation indicates that the insecticide resistance levels diagnosed by the kit were consistent with the results of the diet-overlay bioassay. Moreover, we found a significant negative correlation between diagnostic mortality and the likelihood of control failure for bifenthrin (r = -0.899, p = 0.001), deltamethrin (r = -0.737, p = 0.024) and lambda-cyhalothrin (r = -0.871, p = 0.002). Discussion: The insecticide resistance diagnostic kit for S. frugiperda is a user-friendly tool (portable, short detection time). Its excellent performance qualifies the kit as a reliable screening tool for identifying effective insecticides in sustainable resistance management.

FORMULATION AND EVALUATION OF IMPLANTABLE DRUG DELIVERY OF DISULFIRAM

Disulfiram is widely prescribed to discourage alcoholics from drinking alcohol. The effectiveness of oral disulfiram as a treatment for alcoholism is severely limited due to its poor bioavailability and poor patient compliance. To minimize the failure of the orally administered drug, efforts have been made to prepare alternative dosage form of subcutaneously implantable disulfiram pellets or tablets. In the present study an attempt has been made to design and evaluate a disulfiram implant using plain drug. The disulfiram implants have been formulated by direct compression and the effect of parameters like pH of site of administration (6.0 and 7.4) and sterilization were studied on in-vitro release of implantable disulfiram pellets. In- vitro release has been studied by vial and rotary flask shaker methods. The release kinetic mechanism from all the formulation was found to be zero order. The in vitro release data of all the formulations was compared with that of marketed disulfiram implant (Esperal). In contrast to other formulation in vitro release from marketed formulation appeared to be independent of hydrodynamics of diffusion (volume of dissolution media and agitation speed). The present study had revealed that, in-vitro drug release from implants is unaffected by pH of site of administration and gamma ray sterilization. Both the methods (Vial Method & Rotating Flask Method) of in vitro dissolution testing are found significantly different for formulations prepared in laboratory but not for marketed formulation, indicating the different mechanism of release of marketed formulation.

In-Needle Pre-Column Derivatization for Amino Acid Quantification (iPDAQ) Using HPLC.

Pre-column fluorescent derivatization has been used for the fast quantification of amino acids using high-performance liquid chromatography (HPLC) systems. However, it generally requires an offline in-vial derivatization process with multiple derivatization reagents. The offline derivatization requires the same number of reaction vials as the number of sample vials for use as a reaction chamber for the derivatization reaction in an autosampler. Therefore, the number of samples analyzed per batch using the pre-column derivatization method is halved. To benefit from the pre-column derivatization method, we transformed the derivatization process from an offline chamber process to an online in-needle process (in-needle Pre-column Derivatization for Amino acids Quantification; iPDAQ). Fluorescent derivatization in the injection needle obviated the need for vacant vials as reaction chambers. Consequently, the throughput per batch improved up to two times, and the consumption of derivatization reagents was reduced to less than one-tenth of that in the conventional vial method. We demonstrated to separate and quantify the amino acids in various biological samples. Herein, we presented a novel HPLC-based amino acid quantification method that enables the continuous analysis of a large number of samples. The iPDAQ facilitates accurate amino acid quantification due to the automation of derivatization and achieves improvement in the throughput and reduction of analysis labor.

Magnetically Agitated Nanoparticle-Based Batch Reactors for Biocatalysis with Immobilized Aspartate Ammonia-Lyase

In this study, we investigated the influence of different modes of magnetic mixing on effective enzyme activity of aspartate ammonia-lyase from Pseudomonas fluorescens immobilized onto epoxy-functionalized magnetic nanoparticles by covalent binding (AAL-MNP). The effective specific enzyme activity of AAL-MNPs in traditional shake vial method was compared to the specific activity of the MNP-based biocatalyst in two devices designed for magnetic agitation. The first device agitated the AAL-MNPs by moving two permanent magnets at two opposite sides of a vial in x-axis direction (being perpendicular to the y-axis of the vial); the second device unsettled the MNP biocatalyst by rotating the two permanent magnets around the y-axis of the vial. In a traditional shake vial, the substrate and biocatalyst move in the same direction with the same pattern. In magnetic agitation modes, the MNPs responded differently to the external magnetic field of two permanent magnets. In the axial agitation mode, MNPs formed a moving cloud inside the vial, whereas in the rotating agitation mode, they formed a ring. Especially, the rotating agitation of the MNPs generated small fluid flow inside the vial enabling the mixing of the reaction mixture, leading to enhanced effective activity of AAL-MNPs compared to shake vial agitation.

Isolation of the Human Cytomegalovirus from bodily fluids

In vitro studies on the pathogenesis of the human cytomegalovirus (HCMV) are conducted regularly using laboratory adapted strains that lose some characteristics during the adaptation process. Since HCMV is excreted from bodily fluids during infection or reactivation, this work aimed to isolate and culture HCMV from the MRC-5 human cells found in the urine, bronchoalveolar lavage, saliva, and plasma samples of pediatric patients with probable or confirmed infection. The samples were inoculated on cell cultures either for 14 days or until a cytopathic effect (CPE) of 80 % was observed. The cell lysates and supernatants were used to perform successive viral passages. Besides HCMV, the herpes simplex virus was detected from all the saliva samples. Inoculation of the HCMV positive sera induced cell clustering and immediate monolayer damage that restricted their use. One sample of bronchoalveolar lavage induced a CPE after inoculation like that of the HCMV reference strains (Towne and Merlin), which was consequently propagated and titrated. A second viral isolate derived from the urine sample of a patient with congenital infection did not demonstrate a CPE, although presence of the virus had been confirmed using PCR. The viral isolates were examined and found to be negative for adenoviruses or enteroviruses. Despite the evident difficulty encountered for the isolation and harvesting of the HCMV, this work shows that it was possible to obtain a low passage viral strain using a modified shell vial method and inoculation protocol with extended follow-up and confirmation.

Residual contact vial method for the rapid on-site detection of insecticide resistance in Thrips palmi

Abstract A residual contact vial plus water (RCVpW) bioassay method, in which water was supplemented to minimize control mortality, was established to monitor insecticide resistance in field populations of the melon thrips, Thrips palmi. In the RCVpW, median lethal doses (LD50) of six insecticides commonly used in T. palmi control, were determined at 8 h post-treatment, using a susceptible RDA strain according to the RCVpW protocol. Diagnostic doses for on-site resistance monitoring of the six insecticides, which were determined as doses two-fold higher than required to achieve LD90 in the RDA strain, were in the range of 0.299 to 164.3 μg−1 cm2. Insecticide resistance levels in five field populations of T. palmi were evaluated to test the applicability of RCVpW in monitoring the pest. Although the RDA strain exhibited 100% mortality to diagnostic doses, field populations showed a reduced mortality in response to all test insecticides, indicating different degrees of resistance. In particular, all test field populations exhibited a significantly low mortality in response to spinosad, suggesting a wide distribution of spinosad resistance. Synergistic bioassay revealed that cytochrome P450-mediated metabolic factor is involved in spinosad resistance in the Korean population. Interestingly, an apparently reduced mortality to emamectin benzoate and chlofenapyr was observed in some field populations, perhaps suggesting uneven distribution of resistance to these insecticides in field populations. Our study showed that the RCVpW protocol can be employed both as an on-site resistance monitoring method for major thrip species, and in the selection of appropriate insecticides for their control.

Evaluation of microneedles-assisted in situ depot forming poloxamer gels for sustained transdermal drug delivery

In this study, for the first time, we have reported a sustained transdermal drug delivery from thermoresponsive poloxamer depots formed within the skin micropores following microneedle (MN) application. Firstly, we have investigated the sol–gel phase transition characteristics of poloxamers (PF®127, P108, and P87) at physiological conditions. Rheological measurements were evaluated to confirm the critical gelation temperature (CGT) of the poloxamer formulations with or without fluorescein sodium (FS), as a model drug, at various concentrations. Optimized poloxamer formulations were subjected to in vitro release studies using a vial method. Secondly, polymeric MNs were fabricated using laser-engineered silicone micromolds from various biocompatible polymeric blends of Gantrez S-97, PEG 10000, PEG200, PVP K32, and PVP K90. The MN arrays were characterized for mechanical strength, insertion force determination, in situ dissolution kinetics, moisture content, and penetration depth. The optimized MN arrays with good mechanical strength and non-soluble nature were used to create micropores in the neonatal porcine skin. Microporation in neonatal porcine skin was confirmed by dye-binding study, skin integrity assessment, and histology study. Finally, the in vitro delivery of FS from optimized poloxamer formulations was conducted across non-porated vs microporated skin samples using vertical Franz diffusion cells. Results concluded that permeation of FS was sustained for 96 h across the MN-treated skin samples containing in situ forming depot poloxamer formulations compared to non-microporated skin which sustained the FS delivery for 72 h. Confocal microscopic images confirmed the distribution of higher florescence intensity of FS in skin tissues after permeation study in case of MN-treated skin samples vs intact skin samples.

The National Collection of Arachnida, South Africa: Making the Collection more Accessible

The National Collection of Arachnida (NCA) was established in 1976 at the Agricultural Research Council – Plant Health & Protection (ARC-PHP) in Pretoria, South Africa. This collection forms part of South Africa’s National Assets, which the ARC manages and maintains on behalf of the Department of Agriculture, Forestry and Fisheries (DAFF) and the Department of Science and Technology (DST). The specimen holdings of the NCA contain a wealth of associated taxonomic, biological and geographical information. Currently the collection is managed by a dedicated collection manager responsible for the day-to-day running of the collection assisted by one research assistant. It is utilized for various research activities and knowledge generation in the fields of agriculture and natural resource management. The specimens are preserved using 75% alcohol and held in a double vial method in order to maximize protection of the specimens against evaporation and breakage. Hand-written catalogue books are still used to record and allocate a unique NCA – AcAT number for each specimen. This number links to all primary data recorded for the specimen. Furthermore, the data associated with the specimens are digitized according to Darwin-Core guidelines in an Structured Query Language (SQL) relational database. The database was developed by the ARC-Information Technology services. The entire NCA presently houses approximately 77,780 catalogue entries representing more than 233,300 specimens from six Arachnida orders. The NCA is made up mainly of reference specimens, but also has a type specimen collection of newly described species. The type collection currently contains 1,018 type specimens representing 321 species in 136 genera and 42 families. Of these, 207 specimens are holotypes. The type collection is housed separately from the reference collection and was recently moved to a newly acquired fireproof cabinet. Further planned activities include taking photos of all type specimens using a Zeiss V.16 Zoom microscope so that all type holdings are fully digitized. This will allow the implementation of an electronic loans system. Updating of the types list in the collection will facilitate availability for the wider community. The NCA provides support for key services such as the identification of arachnid predators that have an impact on agricultural production and bio-security as well as a specimen identification and advisory service to government, farmers, industry, researchers, students and the public. These services are essential for research projects on biosystematics and relevant related fields such as conservation, decision-making, agriculture and natural resource management.

Cytomegalovirus Pneumonia In Critically Ill Patients

Cytomegalovirus (CMV) belongs to the human s-herpes virus group with a high seroprevalence in adults, and it is one of the important causes of morbidity and mortality in immunosuppressed patients, i.e, patients with organ transplantation, hematology malignancy and Acquired Immune Deficiency Syndrome (AIDS). The infection is usually latent. Reactivation also occurs in critically ill immunocompetent patients and is associated with prolonged ICU stay and increased mortality. Reactivation occurs when cell mediated immunity is disturbed. Cytomegalovirus infection is rarely monitored and remains unrecognized in critical ill patients1, 2 and CMV incidence is between 0 to 36% in the critically ill population. Infection usually occurs between four to 12 days after hospitalization in ICU with sepsis, mechanical ventilation more than 21 days, and multiple blood transfusions as potential risk factors for CMV reactivation.3 Rapid and accurate diagnosis of the etiology of pneumonia is needed in critically ill patients for a better outcome.4 Cytomegalovirus infection can be detected in tissue biopsy and rapid Polymerase Chain Reaction (PCR) CMV cultures of urine and bronchoalveolar lavage (BAL) fluid with shell vial method.5

Yellow Perch Sperm Motility, Cryopreservation, and Viability of Resulting Larvae and Juveniles

AbstractThe sperm of Yellow Perch Perca flavescens of two different age‐classes, age 0 and 3, were cryopreserved using two different cryoprotectants (dimethylsulfoxide [DMSO] and methanol [MetOH]) with two freezing methods (pellet and vial). The viability and quality of the progenies obtained from fertilization with cryopreserved sperm were then examined. The motility of Walleye Sander vitreus sperm was examined following cryopreservation and ultraviolet (UV) irradiation, with the aim of using heterologous cryopreserved sperm to inseminate Yellow Perch eggs to ensure gynogenesis. The first experiment compared the motility of fresh sperm and pellet method cryopreserved sperm devoid of salmon seminal plasma. Despite the high motility of fresh sperm—75% and 100%—of males age 0 and 3, respectively, the postthaw motility of seminal plasma devoid cryopreserved sperm was 0%. The second experiment addressed the efficiency of pellet and vial freezing methods with DMSO and MetOH supplemented with salmon seminal plasma. Cryopreserved sperm was thawed and motility measured. Sperm motility was not significantly different between pellet (13.3 ± 10.4%) and vial (10.3 ± 12.9%) methods in the absence of sperm extender; however, sperm motility of the pellet method was further improved (20 ± 8.7%) with the addition of sperm extender after thawing, while motility of the vial method sperm (10 ± 7.1%) was not. Cryopreserved sperm was further evaluated based on fertilization rate and ultimate survival and growth of larvae and juveniles through 14 d posthatch. Effects of UV exposure on fresh and pellet method cryopreserved sperm following UV irradiation were also examined. The motility of control sperm cryopreserved with DMSO and MetOH, and UV‐exposed sperm cryopreserved with DMSO decreased from 100% motility before cryopreservation (fresh sperm) to 75% following cryopreservation, while UV‐exposed sperm cryopreserved with MetOH decreased from 100% to 50%. This experiment provides significant new data to improve the effectiveness of straightforward cryopreservation techniques for Yellow Perch.

Mydriatics release from solid and semi-solid ophthalmic formulations using different in vitro methods

The aim of the present paper was the development of semi-solid (hydrogels) and solid (film) ophthalmic formulations for the controlled release of two mydriatics: phenylephrine and tropicamide. The formulations – based on polyvinylalcohol and hyaluronic acid – were characterized, and release studies were performed with three different in vitro set-ups, i.e. Franz-type diffusion cell, vial method and inclined plane; for comparison, a solution and a commercial insert, both clinically used to induce mydriasis, were evaluated. Both gels and film allowed for a controlled release of drugs, appearing a useful alternative for mydriatics administration. However, the release kinetic was significantly influenced by the method used, highlighting the need for optimization and standardization of in vitro models for the evaluation of drug release from ophthalmic dosage forms.

Formation of Multidomain Hydrogels via Thermally Induced Assembly of PISA-Generated Triblock Terpolymer Nanogels

Polymerization-induced self-assembly (PISA) is a rapidly evolving method for the efficient preparation of well-defined nano-objects. PISA-generated nano-objects have been explored in this work for the responsive formation of multidomain hydrogels by thermally induced assembly of doubly thermoresponsive triblock terpolymer nanogels. The nanogels consist of a thermoresponsive poly(diethylene glycol ethyl acrylate) (PDEGA) outer block with a lower thermal transition temperature, a hydrophilic poly(N,N-dimethylacrylamide) (PDMA) midblock, and a N,N′-methylenebis(acrylamide) (BIS) cross-linked, thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) core block with a higher thermal transition temperature. The unique location of these two thermoresponsive blocks of differing transition temperatures in the PDEGA–PDMA–P(NIPAM-co-BIS) nanogels is rationally designed to facilitate room-temperature gelation and is synthetically realized via judicious selection of water–ethanol mixtures under dispersion polymerization conditions. The nanogels were characterized by turbidimetry, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Gelation behavior of the nanogels was investigated by the inverted vial method as well as dynamic rheology sweeps. In comparison with PNIPAM–PDMA–P(DEGA-co-BIS) nanogel and a triblock terpolymer of similar composition, the PDEGA–PDMA–P(NIPAM-co-BIS) nanogels exhibit a good combination of gelation sensitivity and gel strength. The gelation ability, sensitivity, and mechanical properties are affected by the block ratios as well as the cross-linking density in the core of the nanogels.

Comparison of tau-fluvalinate, acrinathrin, and amitraz effects on susceptible and resistant populations of Varroa destructor in a vial test.

The parasitic mite Varroa destructor is a major pest of the western honeybee, Apis mellifera. The development of acaricide resistance in Varroa populations is a global issue. Discriminating concentrations of acaricides are widely used to detect pest resistance. Two methods, using either glass vials or paraffin capsules, are used to screen for Varroa resistance to various acaricides. We found the glass vial method to be useless for testing Varroa resistance to acaridices, so we developed a polypropylene vial bioassay. This method was tested on tau-fluvalinate-, acrinathrin-, and amitraz-resistant mite populations from three apiaries in Czechia. Acetone was used as a control and technical grade acaricide compounds diluted in acetone were applied to the polypropylene vials. The solutions were spread on the vial surface by rolling the vial, and were then evaporated. Freshly collected Varroa females were placed in the vials and the mortality of the exposed mites was measured after 24 h. The Varroa populations differed in mortality between the apiaries and the tested compounds. Mites from the Kyvalka site were resistant to acrinathrin, tau-fluvalinate, and amitraz, while mites from the Postrizin site were susceptible to all three acaricides. In Prelovice apiary, the mites were susceptible to acrinathrin and amitraz, but not to tau-fluvalinate. The calculated discriminating concentrations for tau-fluvalinate, acrinathrin, and amitraz were 0.66, 0.26 and 0.19 µg/mL, respectively. These results indicate that polyproplyne vial tests can be used to determine discriminating concentrations for the early detection of acaricide resistant Varroa. Finally, multiple-resistance in Kyvalka may indicate metabolic resistance.

Reactive extraction of castor seeds and storage stability characteristics of produced biodiesel

In the present study, oil was extracted from a single castor seed by eppendorf vial method, and the oil yield was compared with the yield obtained from Soxhlet method. The oil yield from both methods was about 55% and comparable. Free Fatty Acid (FFA) content of extracted castor oil was found to be lower (<1mg KOH/g oil). Therefore, single step transesterification (reactive extraction) was carried out to study the effect of various reaction variables on the conversion of castor oil biodiesel. The optimum biodiesel conversion of ∼93% was achieved under following conditions: 4h, 1:250 oil to MeOH molar ratio, 1wt.% NaOH, 40°C, 0.75mm particle size, 20g seed, 600rpm and 10 (vol.%) co-solvent. The estimated fuel properties of biodiesel obtained with NaOH, KOH and NaOH (with co-solvent) were found to be similar and within the limits of ASTM standards. Similarly, storage stability of prepared biodiesel was evaluated over a six-month storage period (180 days) under three different storage conditions. The results showed a sharp decrease in fuel stability over time in terms of increase in density from 0.878 to 0.984g/cm3, kinematic viscosity (10.59–16.18cSt), acid value (0.52–5.15mg KOH/g) respectively. While, iodine value significantly decreased from 82.5 to 54.57g I2/100g oil over time. Biodiesel sample stored in the open air degraded faster than samples stored in other storage conditions.

Self-assembled glucose-cored poly (aryl ether) dendron gel for efficient encapsulation and controlled release of guest molecules

Event Abstract Back to Event Self-assembled glucose-cored poly (aryl ether) dendron gel for efficient encapsulation and controlled release of guest molecules Ramya Kannan1, Vignesh Muthuvijayan2 and Edamana Prasad1 1 Indian Institute of Technology Madras, Department of Chemistry, India 2 Indian Institute of Technology Madras, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, India Introduction: Dendrimers/dendrons are well-defined, monodisperse compounds with repeating subunits from a core unit. Self-assembled dendritic systems have been examined for their efficiency to carry and deliver drug molecules in a controlled fashion[1],[2]. Nonetheless, utilizing self-assembled lower generation dendritic structures for drug loading/release has rarely been reported. The proposed work involves the design, synthesis of lower generation dendron-based gel for controlled guest release kinetics under in vitro conditions. The lower generation dendron is designed with complementary chemical functional groups at the periphery so that the amphiphilic dendrons self-assemble to form robust gel with an extensive three dimensional fibrous network, making it an ideal guest release system with controlled release kinetics. Materials and Methods: The first generation (G1) poly (aryl ether) dendron containing glucose moiety, attached through an acyl hydrazone spacer unit, was synthesized based on a previous reported procedure[3]. and estimated using Nuclear magnetic resonance spectrometry (NMR) and Mass spectrometry (MS). The glucose attached poly (aryl ether) dendron self assembles in a solvent mixture (DMSO:Water) to form a stable gel with a critical gelation concentration of 0.1wt%. Structural,morphological and viscoelastic property of the gel was analysed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and rheology measurements. The dendron gel was further loaded with model hydrophilic and hydrophobic dyes and evaluated for its loading efficiency. The release was monitored in vitro in PBS medium at pH 7.4 and release kinetics was fitted with the Peppas model to find out the exponential coefficient, so that an approximate mechanism of the drug release can be elucidated. Results and Discussions: Structure and morphology of the dendron gel were analysed by NMR, Mass spectrometry, FTIR and SEM. SEM images indicate a dense fibrous network of the xerogel (dried gel). FTIR spectrum shows a distinct shift in IR bands of carbonyl groups upon gelation, indicating extensive intermolecular hydrogen-bonding. The amplitude and frequency sweep of the dendron gels exhibited larger values of G’ (storage moduli) compared to the G" (loss moduli) and also showcased a concentration dependent viscoelasticity property of the dendron gel. Maximum loading efficiency of the dendron gel was confirmed by inverted vial method[4] and found that the amount of loading is a function of gelator concentration, molar mass and solubility of the dye. The release kinetics of the dyes from 0.5wt % and 0.7 wt% dendron gels demonstrated sustained release in comparison with the experimental control and curve fitting using Peppas model shows a good fit for the first 60% of the release profile. The exponential coefficient validated non-Fickian diffusion from the dendron gel. Conclusion: In summary, we report a simple dendron based gel to efficiently encapsulate and release small guest molecules under in-vitro conditions. Structural, morphological and viscoelastic studies validated the self-assembly of the dendron. In addition, investigations of the dye release behaviour of dendron gel suggests that the molecules are promising candidates for hosting suitable drug molecules with controlled release kinetics under in vivo conditions[5],[6]. We thank Interdisciplinary program, Department of Chemistry and Department of Biotechnology , IIT Madras for their support; We thank DST-Inspire for the fellowship

Incidence and Characterization of Resistance to Fenpropathrin in Some &lt;I&gt;Liriomyza sativae&lt;/I&gt; (Diptera: Agromyzidae) Populations in Iran

The vegetable leafminer, Liriomyza sativae Blanchard, is a key pest of vegetable and ornamental crops worldwide and is mainly controlled by insecticides. The toxicity of fenpropathrin on adult flies of F1 generation of six Iranian populations of the pest was assessed using the residual glass vial method. The bioassay results showed significant differences in susceptibility to fenpropathrin among the populations tested. Resistance ratios ranged from 5.09 to 28.32. The resistant populations were reared in the greenhouse under fenpropathrin pressure for 14 mo and then susceptibility of both larvae and adults of these strains to fenpropathrin was evaluated. The resistance levels significantly increased in these populations. Further study demonstrated that diethyl maleate and triphenyl phosphate had no synergistic effects on fenpropathrin, however, this compound was significantly synergized by piperonyl butoxide in all tested populations. S,S,S-tributyl phosphorotrithioate also showed a slight synergism with fenpropathrin. Enzyme assays for general esterases, glutathione S-transferases and monooxygenases were performed on adults and larvae of L. sativae. The activity of glutathione s-transferase in different resistant and susceptible strains was not significantly different. The activity of esterases in resistant strains was higher than the susceptible strain. Monooxygenase levels also were higher in resistant strains compared with the susceptible strain. Synergism and biochemical assays revealed that esterases and monooxygenases have a major role in resistance of L. sativae to fenpropathrin.

Bioinspired Synthesis of Cross-Linking of Dopamine-Containing Block Copolymers to Form Thermosensitive Covalent Hydrogels

Marine mussels secrete remarkable mussel adhesive proteins (MAPs) for adherence to the substrates upon which they reside. Inspired by the intermolecular cross-linking characteristics of MAPs, we report the synthesis of thermosensitive dopamine modified Pluronic copolymer (PluF127-Dopa) with high coupling efficiency. Under certain temperature and concentration, PluF127-Dopa copolymers in aqueous solution self-assemble into micelles and are able to rapidly form a more stable hydrogels upon addition of oxidizing reagents such as NaIO4, resulting from oxidative cross-linking of dopamine. UV-vis spectroscopy was utilized to identify the reaction intermediates. The sol-gel transition curves of cross-linked PluF127-Dopa hydrogels (CL-PluF127-Dopa) were determined by a vial inversion method. The critical gelation concentration of CL-PluF127-Dopa hydrogels was significantly lower than those for PluF127-Dopa and unmodified Pluronic F127. The apparent mechanical strength of CL-PluF127-Dopa hydrogels was dramatically enhanced compared to those unmodified Pluronic copolymer hydrogels, suitable for sustained drug delivery. These new biomimetic materials are expected to have potential uses in biomedical applications.

Formulation and evaluation of controlled release ocular inserts of betaxolol hydrochloride

–Betaxolol Hydrochloride is a cardio selective β1 adrenergic receptor blocking agent used in the treatment of chronic open angle glaucoma and ocular hypertension In the present study, an attempt was made to formulate Betaxolol HCl ocular inserts. In matrix type the formulations for Betaxolol containing 10%, 12%, and 14% w/v of Gelatin, 1%, 1.5%, 2%, 2.5% and 3% w/v for Chitosan were prepared by solvent casting method and plasticizer were used in different concentration for smoothing texture of the ocular inserts. The prepared batches of ocular inserts were evaluated for weight variation thickness, drug content uniformity, swelling index. An increase in average weight and thickness is due to increase in polymer concentration. IR spectral studies were performed to confirm the interaction of drug with excipients. All formulations were tested for in vitro drug release (Simulated tear fluid) by vial method. The formulations GH8 and C5 show a maximum cumulative percentage drug release of 98.76% and 97.72% at the end of 12 th hrs, respectively. The drug release in all formulations decreases as the polymer concentration increases. The dissolution data of formulation were subjected to first order, Higuchi’s, and peppas equations. Drug release from the ocuserts by diffusion controlled mechanism. No significant change in the drug content and physical features was observed during storage at 25 0 C/60% RH and 40 0 C/75% RH for the selected formulation for three months. Keywords––Betaxolol Hydrochloride, Chitosan, Gelatin, Ocular inserts.

FIT to be Tried

FIT to be Tried

Sandalwood Fragrance Biosynthesis Involves Sesquiterpene Synthases of Both the Terpene Synthase (TPS)-a and TPS-b Subfamilies, including Santalene Synthases

Sandalwood oil is one of the worlds most highly prized fragrances. To identify the genes and encoded enzymes responsible for santalene biosynthesis, we cloned and characterized three orthologous terpene synthase (TPS) genes SaSSy, SauSSy, and SspiSSy from three divergent sandalwood species; Santalum album, S. austrocaledonicum, and S. spicatum, respectively. The encoded enzymes catalyze the formation of α-, β-, epi-β-santalene, and α-exo-bergamotene from (E,E)-farnesyl diphosphate (E,E-FPP). Recombinant SaSSy was additionally tested with (Z,Z)-farnesyl diphosphate (Z,Z-FPP) and remarkably, found to produce a mixture of α-endo-bergamotene, α-santalene, (Z)-β-farnesene, epi-β-santalene, and β-santalene. Additional cDNAs that encode bisabolene/bisabolol synthases were also cloned and functionally characterized from these three species. Both the santalene synthases and the bisabolene/bisabolol synthases reside in the TPS-b phylogenetic clade, which is more commonly associated with angiosperm monoterpene synthases. An orthologous set of TPS-a synthases responsible for formation of macrocyclic and bicyclic sesquiterpenes were characterized. Strict functionality and limited sequence divergence in the santalene and bisabolene synthases are in contrast to the TPS-a synthases, suggesting these compounds have played a significant role in the evolution of the Santalum genus.