Agar Research Articles

Improvement of Adsorption Capacity by Refined Encapsulating Method of Activated Carbon into the Hollow-Type Spherical Bacterial Cellulose Gels for Oral Absorbent

To reduce the risk of adsorption of granular activated carbon (AC) in the gastrointestinal tract, we successfully prepared a hollow-type spherical bacterial cellulose gel encapsulated with AC (ACEG) and evaluated its pH tolerance and adsorption capacity. The bacterial cellulose gel membrane of ACEG features a three-dimensional mesh structure of cellulose fibers, allowing the selective permeation of substances based on their size. In this study, the preparation method of ACEGs was investigated, and the indole saturation adsorption capacity of the obtained gel was measured. We modified the gel culture nucleus gel from calcium alginate gel to agar gel, facilitating the encapsulation of previously challenging particles. The new preparation method used sodium hydroxide solution for sterilization and dissolution to remove the debris of Komagataeibacter xylinus, which was feared to remain in the bacterial cellulose membrane. This treatment was also confirmed to have no effect on the adsorption capacity of the AC powder. Therefore, this new preparation method is expected not only to improve the performance of ACEGs but also to be applied to a wide range of adsorbent-encapsulated hollow-type bacterial cellulose gels.

A modular, human body-mimicking phantom with active thermoregulation capabilities for validation and verification of convective hyperthermia devices

Objectives This study aims to design and fabricate a modular phantom for hyperthermia applications, addressing interpatient variability in thermal regulation mechanisms like sweating rate, metabolic heat production, and blood redistribution. Materials & methods The phantom can be constructed in various weights and dimensions by connecting identical units. Each unit consists of an agar-based block, an ethyl cellulose-based top layer, a heat source, deep and superficial water circulation, and a sweating mechanism. Agar and ethyl cellulose gels mimic the thermal properties of human tissues and fat respectively. The blocks are wrapped in PVC foil to prevent water evaporation. A heating wire, coiled around an embedded aluminum tubing simulates metabolic heat production. A superficial water circulation mimics skin capillaries. A water pump ensures a steady flow rate throughout the tubing system. Sweat production is simulated using a water pump and perforated tubing. A programmed controller maintains core temperature in a normal operating mode and simulates an anesthetized patient in anesthesia mode. Results Temperature uniformity and regulation were assessed under varying environmental conditions. The phantom effectively regulated its core temperature at 37.0 °C +/- 0.7 °C with an ambient temperature ranging between 21 °C and 30 °C. Activating the water circulation reduced the maximum temperature gradient within the phantom from 4.70 °C to 1.92 °C. Conclusion The versatile phantom successfully models heat exchange processes. Its thermal properties, dimensions, and heat exchange rates can be tuned to mimic different patient models. These are promising results as an effective tool for hyperthermia device validation and verification, representing human physiological responses.

Gel Cleaning in Heritage: Comparison of the Water Release among Gels and Traditional Pads

Water release is a crucial aspect when considering cleaning effects on water-sensitive materials. In conservation practice, a water-based cleaning method which limits water release is very often needed. Unfortunately, this is not accompanied by an appropriate measure of the effectively released water. In this paper, water release has been measured by comparing traditional cleaning formulations, such as paper pulp and sepiolite, with several gar gel formulations, used by both Italian and European conservators. The assessment has been carried out by the gravimetric method, using three different stone material specimens as reference: Noto calcarenite, Manciano sandstone and Black Bergamo limestone, whose porosity values and distributions are known. Moreover, water distribution has been evaluated by portable NMR tests. Different commercial agar gel products (Bresciani, CTS, Sigma), having different concentrations (3, 4, and 5%), application modes (rigid at room T or fluid warm gels, with and without inserting Japanese tissue paper), and geometry (horizontal in gravity force direction or vertical), have been compared to obtain a full scenario among different water release mechanisms present in real conservation works. The paper faces the important issue of preparing reproducible chemical or water pads as well, useful for further research aimed at comparing cleaning effects in heritage conservation. The most interesting quantitative results can be summarized as follows. The water release measured from paper pulp and sepiolite was found to be 2 to 4 times higher than from any tested agar gel. Water release decreases by increasing agar concentration; an increase in the agar concentration by 1% induces a decrease in water release in the range 16.98–66.88 g depending on the stone; the increase from 4% to 5% is more obvious with respect to that from 3% to 4%. It is possible to assess the effect of the presence of Japanese paper, which is able to reduce the water release from 18 to 76%, depending on the stone and on the agar used. The gravimetric results were also used in the preliminary calibration tests of a contact probe named System Unit Salinity Index (SUSI), recently patented and useful in providing humidity and salinity indexes in a given porous material.

Biotoxicity Evaluation of Biodegradable Polymeric Particles: Exploring the Possible Adverse Impacts on Biological Systems

ABSTRACTThis study aimed to investigate the impact of plastic particles on cell viability and tissue toxicity. The cells were subjected to incubation with plastic particles immobilized in agar gels, resulting in minimal cell death and cytotoxicity. Furthermore, direct exposure of various cell types to suspended plastic particles showed negligible effects on cell viability, with no observed lysis or growth inhibition. Staining techniques revealed minimal plastic particle‐induced cell death, with the majority of cells remaining viable. However, histological evaluations of mouse tissues demonstrated that the nondegradable low‐density poly(ethylene) (LDPE) groups exhibited severe irritation, characterized by an excessive presence of macrophages, neutrophils, fibrosis, fat infiltration, and increased blood vessel formation in subcutaneous tissue. In contrast, biodegradable neat poly(butylene succinate) (KRICT‐PBS) and cellulose nanocrystals/PBS nanocomposite (CNC‐PBS) groups induced minimal toxicity. Interestingly, the intravenous injection of KRICT‐PBS and CNC‐PBS degradate solutions in mice exhibited mild toxicity, suggesting no significant damage to normal kidney and liver function.

Make it a standard? The creation and variability assessment of a consensus standard protocol for Tenebrio molitor larvae feeding trials

Abstract Interest in the nutrition of the yellow mealworm (Tenebrio molitor L.) larvae is on the rise, leading to an increase in publications on this topic. The absence of a standard protocol and resulting differences in experimental designs reduces comparability among studies and impedes research on mealworm nutrition. To address this, a consensus standardised protocol was developed specifically for the evaluation of mealworm larval growth and performance in feeding trials. The efficacy of this protocol was evaluated through an international ring test involving seven partners using two wheat brans as dry feed (a standard bran and a local bran) at 27 °C and 60% relative humidity. As experimental units, plastic crates filled with 2.1 kg of bran and 10,000 4-week-old larvae were used with six replicates. Agar gel was provided as wet feed ad libitum. The mean individual larval weight and the number of larvae per crate were determined weekly until either three or more replicates ran out of feed or pupation exceeded 10%. At harvest, the total larval fresh biomass and amount of frass was determined. Larval samples were taken for chemical analysis. To assess the protocol, the within (repeatability) and between (reproducibility) laboratory variability was calculated for each parameter. The repeatability was good (limit at 12% (standard) and 14% (local)). The reproducibility was poorer with a limit 2.7 times higher for the standard feed (36%) and 3.8 times higher for the local feed (55%). For both feeds, the total larval fresh harvest, amount of frass and the larval protein concentration were the most consistent both within and among laboratories. The highest variability was observed at the early life stages and for the larvae ash content. The detailed consensus standard protocol and repeatability/reproducibility estimates can be used as basis for future mealworm feeding trials, comparing results and future improvements.

Assessing the effects of NapA gene overexpression on denitrification and denitrogenation in magnetospirillum gryphiswaldense MSR-1.

Previous research on Magnetospirillum gryphiswaldense MSR-1 found that MSR-1 has a good denitrification nitrogen removal ability and specific application prospects in the sewage biological nitrogen removal field. Therefore, this study selected the essential denitrification gene NapA in MSR-1-wt for overexpression, and the overexpressed MSR-1-NapA was successfully constructed. Q-PCR amplification experiment and AGAR gel electrophoresis experiment proved that the relative transcription level of the NapA gene was increased by more than four times, and the denitrification ability of MSR-1-wt and MSR-1-NapA was further determined by enzyme activity experiment, denitrification experiment, and flow cytometry. The results showed that overexpression of the NapA gene increased nitrate reductase activity in MSR-1-NapA by more than four times. In the solution with a nitrate concentration of 118.33 ± 3.23mgN/L, the denitrification efficiency of MSR-1-NapA was superior to that of MSR-1-wt, significantly enhancing both the denitrification and nitrogen removal capacities of MSR-1. This indicates its greater potential for biological nitrogen removal in wastewater treatment.

Mechanical, electrical, and piezoresistive properties of modified conductive recycled fine aggregate smart mortar

The application of recycled fine aggregates (RFA) in smart conductive mortar is of great significance for conserving natural resources and protecting the environment. However, the high water absorption and microstructural defects of RFA limit its widespread use in smart conductive mortar. This study employs an agar gel impregnation treatment containing graphite particles to improve the properties of RFA. The resulting modified conductive recycled fine aggregate (M-RFA) exhibited a 2.8 % reduction in water absorption. The workability, mechanical properties, electrical properties, and self-sensing capabilities of the modified recycled fine aggregate mortar (M-RFAM) were studied. It was found that the workability and mechanical properties of the smart conductive mortar prepared with M-RFA were slightly reduced but remained within acceptable ranges (28-day compressive strength greater than 33 MPa). At the same time, it achieved low resistivity and high strain-sensing sensitivity, with the highest strain-sensing sensitivity being 61.9 (30 times higher than ordinary strain gauges). The influence of loading rate and moisture content on the self-sensing ability of conductive mortar was also investigated, revealing a positive correlation between moisture content and stress-sensing ability. Furthermore, the study found that factors such as AC frequency, curing age, moisture content, and temperature significantly affect resistivity. These factors should be considered in practical applications and further research.

Evidence of G1-G3 Complex Life Cycle of Echinococcus granulosus sensu stricto Through Molecular Characterization (Genotyping) in Dogs, Sheep, Goats and Humans of North-western Himalayas, India

Background: The helminthic zoonotic disease echinococcosis is brought on by tapeworms that are members of the genus (Family Taeniidae). Currently, Echinococcus granulosus, Echinococcus multilocularis, Echinococcus vogeli, Echinococcus oligarthrus and Echinococcus shiquicus are identified species. Of them, E. granulosus and E. multilocularisare important zoonotic organisms that cause cystic echinococcosis and alveolar echinococcosis in humans, respectively (Bowles and McManus, 1993). Echinococcus granulosus is mainly spread by dogs and a few other intermediate hosts, although it is hardly ever a part of a naturally occurring predator-prey cycle that is not caused by humans. Methods: In a present study, 1254 small ruminants (723 sheep and 531 goats) and 305 dogs, including 122 pet dogs visiting small animal clinics, 183 stray dogs in Jammu division, for a period of 12 months (July, 2021- June, 2022) were taken for the detection of the prevalence of cystic echinococcosis and molecular detection. Result: Among sheep and goats, 209 animals (sheep = 137 and goats = 72) were found infected with hydatidosis with an overall infection rate of 16.67% (sheep = 18.95% and goats = 13.56%). Molecular prevalence based on copro PCR was conducted in dogs, in which the overall prevalence of Echinococcus was found to be 14.09% [stray (22.95%); pet (0.82%)]. For the identification of Echinococcus species from cyst of sheep, goats and humans, a PCR protocol employing the Cox1 primers was used. The amplified products of PCR were electrophoretically separated on agar gels (1%) and analysed in a gel documentation system. Clear amplification was noticed at 440 bp for sheep, goat andhuman. The generated Cox1 partial sequences were assigned theaccession numbers as: dog (ON427821), goat (ON427822), sheep (ON427823), human 1(OP215294) and human 2 (OP215295). All the Cox1 sequences from dog, goat, sheep and humans were clustering in same clade, irrespective of their geographical location, representingthe cycle of transmission in Jammu region as Echinococcus granulosus G1-G3 complex.

Fabrication of Magnetic Ferrofluid Microrobot for Tissue Mechanical Measurement

Ferrofluids are a uniform mixture of magnetic nanoparticles and a carrier liquid, such as water or oil. They have become increasingly popular in the medical field due to their biocompatibility, manipulability, and their wide range of possible medical applications, one of them being mechanical measurement in human tissues. Our goal is to fabricate a bio-compatible ferrofluid droplet to perform these mechanical measurements. To fabricate the ferrofluid, magnetite nanoparticles (Fe3O4) were chosen along with vegetable oil as the carrier liquid due to their biocompatibility. The magnetic nanoparticles were also coated with oleic acid to serve as a lubricant layer to prevent them from agglomerating. We first coated the magnetic particles (Nanoshel) with oleic acid (Sigma). The magnetic particles were added to distilled water that was heated up to 60oC and mechanically stirred at 500 rpm. For each gram of magnetic nanoparticles used, an equal amount of oleic acid was added into the mixture and stirred for 15 minutes. The coated particles were then rinsed with distilled water followed by ethyl alcohol and dried. To fabricate the ferrofluid, we mixed the vegetable oil with the nanoparticles overnight to ensure uniform mixing with weight rations including 30%wt, 40%wt, and 50%wt, to find the optimal ratio for magnetic control and stability. To validate the technology using ferrofluid to perform tissue mechanical measurement, a droplet of ferrofluid was injected into the agar gel mimicking the stiffness of tissue and then actuated with a magnet. The ferrofluid showed observable deformation under a microscope after magnetic actuation. Our next steps will include repeating this process under a controlled gradient magnetic field while using a camera to track its deformation and movement and from there the hope is to perform on human tissue.

Nucleation mechanism in the absence and presence of an electric field

The objective of this article is to investigate the mechanism of the ice nucleation process theoretically by assaying the thermodynamics of the ice nucleus as a small system, and experimentally verified by studying the effect of the static electric field on the ice nucleation process. Using the thermodynamic of small system related to Hill, we predicted that the equilibrium temperature of water and ice nucleus decreases with the reduction of nucleus size. By applying an electrostatic field, the Gibbs free energy of nucleus formation decreases due to this fact that the electrostatic work on the ice nucleus is lower than that for bulk water which it causes a decrease in the critical size of the ice nucleus. The experimental results showed that the nucleation temperature of water increases by applying the electric field with the voltage of 4.5 kV (internal strength of 2.2 × 104 V/m) while the size of ice crystals decreases in the frozen agar gel at the presence of electric field.

Utilizing Reactant-Infused Agar Gel to Model the Effect of Solid Reactant Particle Size on Reaction Rate

Utilizing Reactant-Infused Agar Gel to Model the Effect of Solid Reactant Particle Size on Reaction Rate

Analysis of root-environment interactions reveals mechanical advantages of growth-driven penetration of roots.

Plant roots are considered highly efficient soil explorers. As opposed to the push-driven penetration strategy commonly used by many digging organisms, roots penetrate by growing, adding new cells at the tip, and elongating over a well-defined growth zone. However, a comprehensive understanding of the mechanical aspects associated with root penetration is currently lacking. We perform penetration experiments following Arabidopsis thaliana roots growing into an agar gel environment, and a needle of similar dimensions pushed into the same agar. We measure and compare the environmental deformations in both cases by following the displacement of fluorescent beads embedded within the gel, combining confocal microscopy and Digital Volume Correlation (DVC) analysis. We find that deformations are generally smaller for growing roots. To better understand the mechanical differences between the two penetration strategies, we develop a computational model informed by experiments. Simulations show that, compared to push-driven penetration, grow-driven penetration reduces frictional forces and mechanical work, with lower propagation of displacements in the surrounding medium. These findings shed light on the complex interaction of plant roots with their environment, providing a quantitative understanding based on a comparative approach.

Synthesis and characterization of aloe vera and hyaluronic acid-infused agar-agar/ gelatin-based biopolymeric gel for potential skincare applications

The demand for bioactive and biodegradable skincare products is growing with rising skin complications despite bare cosmetics, pharmaceuticals, and nutraceuticals. Biocompatible, Agar-agar (AA) and gelatin (G) based biopolymeric gel infused with hyaluronic acid (HA) and aloe vera (AV)) is suitable for burn treatment and wound healing. This proposed gel with HA and AV showed therapeutic effects due to its hydrating, antibacterial, and angiogenic potential. The said biopolymeric gels were characterized in both in-vitro and in-vivo studies, revealing their potential to replace synthetic and conventional cosmeceuticals. The adequately porous structure of the biopolymeric gels was evident from the scanning electron microscope (SEM) images, which allows the release of AV and HA. Fourier Transform Infrared (FTIR) spectroscopic analysis revealed the peaks attributed to secondary amine (-NH bond) in AA/G biopolymeric gel, which confirmed the crosslinking between AA and G. The degradation profile of biopolymeric gels showed the rapid release of AV and HA during the first hour of incubation, supporting the idea of minimal application time of biopolymeric gels. AV-infused AA/G/HA gel was highly bactericidal, with only 27 % of the E. coli population appearing viable. Similar behavior was seen against S. aureus, and 33 % of the cells seemed viable, confirming the antibacterial potential. In-vivo chorioallantoic membrane assay confirmed neo-vascular ability and angiogenic potential as the number of branched vessels for AA/G/HA was 6 ± 1 and a significant increase in the number of branched chain vessels was seen for AA/G/HA/AV, as 12 ± 2 due to the presence of HA. The results infer that the AA/G biopolymeric gels infused with AV and HA can effectively be used for burn treatment and wound healing.

Direct Three-Dimensional Mass Spectrometry Imaging with Laser Ablation Remote Atmospheric Pressure Photoionization/Chemical Ionization.

The laser ablation remote atmospheric pressure photoionization/chemical ionization (LARAPPI/CI) platform coupled to an ultrahigh resolution quadrupole-time-of-flight (QToF) mass spectrometer was developed and employed for the first direct three-dimensional (3D) mass spectrometry imaging (MSI) of metabolites in human and plant tissues. Our solution for 3D MSI does not require sample modification or cutting into thin slices. Ablation characteristics of an optical system based on a diffraction optical element are studied and used for voxel stacking to directly remove layers of tissues. Agar gel, red radish, kiwi, human kidney cancer, and normal tissue samples were used for the tests of this new system. The 2D and 3D ion images vividly illustrate differences in the abundances of selected metabolites between cancerous and noncancerous regions of the kidney tissue and also between different parts of plant tissues. The LARAPPI/CI MSI setup is also the first example of the successful use of combined dopant-assisted atmospheric pressure photoionization (DA-APPI) and atmospheric pressure chemical ionization (APCI) ion source for mass spectrometry imaging.

Structure, characterization, and application of a novel thermoreversible emulsion gel fabricated by citrate agar

A novel thermoreversible emulsion gel was successfully prepared with citrate agar (CA) as the sole emulsifier. Compared with native agar gel emulsion, CA gel emulsion (CAGE) formed a stable emulsion gel when the CA concentration was increased to 1.25 % (w/w). Results of time-temperature scanning experiments showed that the emulsion gel rapidly transformed into liquid emulsion when heated to 40–50 °C and then solidified into emulsion gel after cooling to the critical temperature of solidification. The emulsion gel had stable sol–gel transformation ability after seven cycles repeated heating–cooling treatment (HCT) at 85 °C and 4 °C. However, the stability of emulsion gels gradually decreased because of the large-droplet formation during heating, which affected the CA molecular-reconfiguration network structure in cooling. The conjunction analysis of microstructure and properties of the emulsion gel indicated that its stability depended primarily on the spatial repulsion and electrostatic repulsion provided by CA gel, and the main factor driving thermal reversibility was the temperature-responsive gelation performance of CA. The retention of quercetin was >90.23 % after seven HCTs because CAGEG enhanced the homogeneity and stability of the droplets.

Potentially pathogenic culturable bacteria in hemodialysis waters

BackgroundHemodialysis patients are at risk of acquiring healthcare-related infections due to using non-sterile water to prepare hemodialysis fluid. Therefore, microbiological control and monitoring of used water are of crucial importance.Materials and methodsIn this work, we identified bacterial populations occupying a hemodialysis water distribution system for almost a 6-month period in Ahvaz city, southwest of Iran. A total of 18 samples from three points were collected. We found high colony counts of bacteria on R2A agar. 31 bacteria with different morphological and biochemical characteristics were identified by molecular-genetic methods based on 16 S rRNA gene sequencing. Endotoxin concentrations were measured, using Endosafe® Rapid LAL Single-Test Vials.ResultsA diverse bacterial community was identified, containing predominantly Gram-negative bacilli. The most frequently isolated genus was Sphingomonas. Five species including M. fortuitum, M. lentiflavum, M.szulgai, M. barrassiae, and M. gordonae was identified .Despite the presence of Gram-negative bacteria the endotoxin analysis of all samples revealed that their endotoxin values were below the detection limit.ConclusionThe members of Sphingomonas genus along with Bosea and mycobacteria could be regarded as pioneers in surface colonization and biofilm creation. These bacteria with others like Pelomonas, Bradyrhizobium, staphylococcus, and Microbacterium may represent a potential health risk to patients under hemodialysis treatment.

Evaluating Commercial Electrical Neuromodulation Devices with Low-Cost Neural Phantoms

Non-invasive transcranial electrical stimulation is a category of neuromodulation techniques used for various disorders. Although medically approved devices exist, the variety of consumer electrical stimulation devices is increasing. Because clinical trials and animal tests are costly and risky, using a brain phantom can provide preliminary experimental validation. However, existing brain phantoms are often costly or require excessive preparation time, precluding their use for rapid, real-time optimization of stimulation settings. A limitation of direct electric fields in a phantom is the lack of 3D spatial resolution. Using well-researched modalities such as transcranial direct current stimulation (tDCS) and newer modalities such as amplitude-modulated transcranial pulsed-current stimulation (am-tPCS), a range of materials was tested for use as electrical phantoms. Based on cost, preparation time, and efficiency, ground beef and agar gel with a 10% salt mix were selected. The measured values for the total dosages were 0.55 W-s for am-tPCS and 0.91 W-s for tDCS. Due to a low gain on the recording electrodes, the signal efficiency measured against the power delivered was 4.2% for tDCS and 3.1% for am-tPCS. Issues included electrodes shifting in the soft material and the low sensitivity of the recording electrodes. Despite these issues, the effective combination of the phantom and recording methodologies can enable low costs and the rapid testing, experimentation, and verification of consumer neuromodulation devices in three dimensions. Additionally, the efficiency factors (EFs) between the observed dosage and the delivered dosage could streamline the comparison of experimental configurations. As demonstrated by comparing two types of electrical neuromodulation devices across the 3D space of a phantom, EFs can be used in conjunction with a cost-effective, time-expedient phantom to rapidly iterate and optimize stimulation parameters.

A human monoclonal antibody based immunoenzymetric assay to measure Fel d 1 concentrations in cat hair and pelt allergenic extracts.

In the United States, 19 allergen extracts of different specificities are standardized, which means that their potencies are determined in comparison to a US reference standard. For cat allergen extracts, potency is determined by measuring Fel d 1 content expressed in in Fel d 1 units, and with a unitage that correlates with skin test reactions (bioequivalent allergy units or BAU). Currently, Fel d 1 content is measured with a radial immunodiffusion (RID) assay that uses polyclonal sheep antisera to detect the allergenic protein by producing a white precipitin line in agar gel. However, the RID is considered cumbersome, and the polyclonal sera may qualitatively vary among animals and may recognize epitopes irrelevant to human allergic disease. In this report, we describe a quantitative two-site immunoenzymetric assay (IEMA) for Fel d 1 that uses immobilized capture and soluble biotin-labeled detection Fel d 1-specific human IgE monoclonal antibodies (mAb) that have been class-switched to IgG4. Together, they sandwich Fel d 1 molecules from extracts. Using purified natural Fel d 1 as a calibrator, the historically reported ∼4 micrograms Fel d 1/Fel d 1 unit assignment was directly measured in this mAb-based IEMA at 3.12 ± 0.24 micrograms of Fel d 1 per Fel d 1 unit. This IEMA appears to be equivalent to RID in the measurement of biological potencies of commercial cat hair and cat pelt extracts marketed in the United States.

Characterization of predominant genotype (QX) of avian infectious bronchitis virus isolated from layer chickens in Bangladesh

Avian infectious bronchitis (AIB) is a highly transmissible infection that affects the poultry industry globally. This study aims to isolate and characterize emerging strains of infectious bronchitis virus (IBV) from field samples of layer chickens in Bangladesh. A total of 108 samples (trachea, lung, and kidney) were taken from dead and sick layer chickens from 18 farms in 4 areas detecting outbreaks in Bangladesh. The samples were processed and inoculated in embryonated chicken eggs (ECEs) and finally screened by the trypsin-induced hemagglutination (THA) test. Using various techniques such as hemagglutination inhibition (HI), agar gel immuno-diffusion (AGID), virus neutralization test (VNT), reverse transcription-polymerase chain reaction (RT-PCR), and nucleotide sequencing, we were able to identify and confirm the isolated IBV viruses. The study also determined the hemagglutination (HA) pattern of isolated virus using avian and mammalian red blood cells. The pathogenicity of the isolated IBV was determined using embryonated chicken eggs and day-old chicks. The study found that 8 samples were positive for IBV using ECEs, and 4 were positive by the THA test. These isolates were confirmed using HI, AGID, and VN tests. S1 gene-based RT-PCR confirmed all four isolates as IBV, with the recent isolates belonging to the genotype-QX and being similar to IBV isolates from Thailand, Saudi Arabia, and India. The HA pattern of the recent isolates showed that the isolated IBV was virulent. The pathogenicity test also revealed that the four isolates were highly pathogenic. The study indicated that the prevalent genotype (QX) of the IBV strain is present in the layer chicken population of Bangladesh.

Expression of VP2 protein of novel goose parvovirus in baculovirus and evaluation of its immune effect

Short-beak and dwarfism syndrome (SBDS) is a new disease caused by a genetic variant of goose parvovirus in ducks that results in enormous economic losses for the waterfowl industry. Currently, there is no commercial vaccine for this disease, so it is urgent to develop a safer and more effective vaccine to prevent this disease. In this study, we optimized the production conditions to enhance the expression of the recombinant VP2 protein and identified the optimal conditions for subsequent large-scale expression. Furthermore, the protein underwent purification via nickel column affinity chromatography, followed by concentration using ultrafiltration tube. Subsequently, it was observed by transmission electron microscopy (TEM) that the NGPV recombinant VP2 protein assembled into virus-like particles (VLPs) resembling those of the original virus. Finally, the ISA 78-VG adjuvant was mixed with the NGPV-VP2 VLPs to be prepared as a subunit vaccine. Furthermore, both agar gel precipitation test (AGP) and serum neutralization test demonstrated that NGPV VLP subunit vaccine could induce the increase of NGPV antibody in breeding ducks. The ducklings were also challenged with the NGPV, and the results showed that the maternal antibody level could provide sufficient protection to the ducklings. These results indicated that the use of the NGPV VLP subunit vaccine based on the baculovirus expression system could facilitate the large-scale development of a reliable vaccine in the future.