Hank's Balanced Salt Research Articles

Advancing biodegradable Mg-Gd-Y alloy for cardiovascular stent applications

The implants of percutaneous coronary intervention are making progress to periodic degradation and the reduction of complications. Thus, magnesium alloys have emerged as excellent candidate materials for preparing cardiovascular stents due to their excellent biodegradability and biocompatibility. This study investigates the effect of Gd content on the mechanical properties and corrosion behavior of Mg-xGd-5Y alloys. The results indicate that Gd dissolved in the Mg matrix, enhancing ultimate tensile strength (UTS of 344MPa) through a solid solution-strengthening effect and activating Prismatic <a> slip systems to enhance elongation (EL of 15.7%). The Pilling-Bedworth ratio (PBR) of Mg-xGd-5Y alloys was analyzed after being immersed in Hank's Balanced Salt Solution for 24h, with Mg-10Gd-5Y exhibiting a PBR value of 1.1. Furthermore, the product film of Mg-xGd-5Y alloys, mainly oxides and carbonates, effectively improved corrosion resistance. Mg-xGd-Y alloys with low Gd content (Gd≤10wt.%) demonstrated good cell compatibility with L929 cells (relative growth rate≥75%). These results suggest that Mg-xGd-5Y alloys (Gd≤10wt.%) have significant potential for cardiovascular stent application.

Sperm handling and management in the teleost model fish Japanese medaka (Oryzias latipes)

Japanese medaka (Oryzias latipes) has been used as a model organism in different research fields, including reproductive physiology. Sperm motility is the most important marker for male fertility in fish and, thus, reproduction success. However, because of small volume of ejaculate and short motility duration, it is still challenging to manage the sperm collection and analysis in small model fish. In the present study, we aimed to investigate sperm motility and to optimize sperm collection, short-term sperm storage, and cryopreservation in Japanese medaka (Oryzias latipes). Using two different approaches for sperm collection: testes dissection and abdominal massage, different housing conditions and activating the sperm with different activation solutions, we investigated immediate sperm motility. In the second part of this study, we used different osmolalities of immobilization solution, Hank's Balanced Salt Solution (HBSS) for sperm storage at 0, 2 and 3 h after sperm collection. Finally, the sperm were cryopreserved using methanol as cryoprotectant and HBSS as extender at two different osmolalities, and post-thaw sperm motility was investigated. The highest post-activating sperm motility was achieved in the groups activated by the extender at 300 mOsm/kg. The quality of sperm remained unaffected by co-housing with females or with males only. Furthermore, Hanks’ Balanced Salt Solution (HBSS) with an osmolality of 600 mOsm/kg demonstrated its efficacy as a suitable extender for sperm storage, preserving motility and progressivity for 3 h. The highest post-thaw motility was around 35%. There were no significant differences between post-thaw motility in different groups. We also found that post-thaw incubation on ice can maintain the motility of the sperm for up to one hour after thawing.

In vitro immersion study and characterization of biomimetic bovine hydroxyapatite scaffolds: Influence of calcination temperature (600 and 1000 °C) on apatite formation

This work reports on the properties of natural bovine hydroxyapatite (HAp) scaffolds calcined at temperatures of 600 and 1000 °C and on the effects of apatite formation on these calcined scaffolds during immersion experiments in Hank's Balanced Salt Solution (HBSS) from 0 to 28 days. The study systematically identifies different mechanisms that determine the formation of the apatite layer. First, compositional analysis of the scaffolds by inductively couple plasma (ICP) reveals significant differences in macromineral content, which includes calcium, phosphorus, magnesium, and sodium. Subsequent X-ray diffraction (XRD) analysis reveals the presence of hydroxyapatite in both scaffolds, while the 1000 °C sample has additional β-whitlockite due to the higher calcination temperature. Further investigation by Fourier Transform Infrared Spectroscopy (FTIR) and Raman analyzes revealed carbonated HAp in the 600 °C scaffolds and characteristic bands of HAp in the 1000 °C scaffolds. Morphological changes during immersion, documented by Scanning Electron Microscopy (SEM) images, display leaf-like and cauliflower-like structures in the 600 °C sample and rash-like features leading to leaf-type apatite formation in the 1000 °C sample. High-Resolution Transmission Electron Microscopy (HR-TEM) showed elongated crystals in both samples, confirming exclusive HAp presence in the 600 °C sample and the coexistence of HAp and β-whitlockite phases in the 1000 °C sample. After 28 days of immersion, TEM images at 600 °C reveal ordered apatite particles, while the 1000 °C images exhibit random apatite formation, confirmed by Energy Dispersive X-ray Spectroscopy in TEM (EDS-TEM). In addition, both scaffolds calcined at 600 and 1000 °C showed biocompatibility, as cytotoxicity tests confirmed a remarkable 100 % cell viability, underlining their non-toxicity. The scaffolds calcined at 600 and 1000 °C therefore exhibit high bioactivity and viability, supporting their suitability for bone tissue engineering applications.

Isolated bovine pancreatic islets as an alternate in vitro model for diabetes research.

Background & objectives Isolation of functional pancreatic islets for diabetes research and clinical islet transplantation stands as a big challenge despite the advancements in the field. In this context, the non-availability of human/animal tissues is one of the major impediments to islet-based research, which has tremendous scope for translation. The current study explores the feasibility of using the bovine pancreas as an alternative source to isolate pancreatic islets and assess its functionality for in vitro studies. Methods The bovine pancreas was collected from a registered slaughterhouse and transported in an ice-cold medium - Hank's Balanced Salt Solution (HBSS) to the laboratory. Islets were isolated by sequential collagenase digestion followed by a two-step filtration and purification by density gradient separation method. After isolation, islets were identified with dithizone staining and the islet function was assayed in vitro for assessing the dynamic insulin secretory function by monitoring the glucose-stimulated insulin secretion (GSIS), in response to low and high glucose. Staining techniques were also used to understand the cytoarchitecture of the bovine pancreas. Results The islet yield was 157±23 islets per gram of pancreas and was viable. The cold ischaemia time was reduced to 60-75 min. The islets released insulin with glucose stimulation. The insulin release was observed more with high glucose (28 mM) than with low glucose (2.8 mM). Dithizone staining confirmed the presence of islets after isolation and the size of islets ranged from 50 to 600 µm size. The mantled islets (islets with acinar tissue) were also noted with the pure islets in culture. Hematoxylin and eosin (H&E) and aldehyde- fuchsin showed islets interspersed in the acinar tissue of the bovine pancreas. Special stain defined the islets better than regular staining. Fluorescent and diaminobenzidine (DAB) staining with insulin, glucagon and somatostatin revealed the arrangement of the cells in each islet. The beta cells were majorly found in the islet core with alpha cells interspersed with the delta cells in the periphery. Interpretation & conclusions The isolation procedure described in this study yielded viable islets for in vitro studies which showed a differential response to glucose challenge, confirming their viability. We provide a simple and reproducible method for small-scale isolation of functional islets from the bovine pancreas. This model proffers the beginner a hands-on in islet experiments and helps to re-iterate the process that could be extrapolated to other pancreatic tissues as well as to expand on diabetes research.

The Probiotic Lactobacillus reuteri Preferentially Synthesizes Kynurenic Acid from Kynurenine.

The gut-brain axis is increasingly understood to play a role in neuropsychiatric disorders. The probiotic bacterium Lactobacillus (L.) reuteri and products of tryptophan degradation, specifically the neuroactive kynurenine pathway (KP) metabolite kynurenic acid (KYNA), have received special attention in this context. We, therefore, assessed relevant features of KP metabolism, namely, the cellular uptake of the pivotal metabolite kynurenine and its conversion to its primary products KYNA, 3-hydroxykynurenine and anthranilic acid in L. reuteri by incubating the bacteria in Hank's Balanced Salt solution in vitro. Kynurenine readily entered the bacterial cells and was preferentially converted to KYNA, which was promptly released into the extracellular milieu. De novo production of KYNA increased linearly with increasing concentrations of kynurenine (up to 1 mM) and bacteria (107 to 109 CFU/mL) and with incubation time (1-3 h). KYNA neosynthesis was blocked by two selective inhibitors of mammalian kynurenine aminotransferase II (PF-048559989 and BFF-122). In contrast to mammals, however, kynurenine uptake was not influenced by other substrates of the mammalian large neutral amino acid transporter, and KYNA production was not affected by the presumed competitive enzyme substrates (glutamine and α-aminoadipate). Taken together, these results reveal substantive qualitative differences between bacterial and mammalian KP metabolism.

Evaluation of Corrosion Performance of AZ31 Mg Alloy in Physiological and Highly Corrosive Solutions.

Resorbable Mg and Mg alloys have gained significant interest as promising biomedical materials. However, corrosion of these alloys can lead to premature reduction in their mechanical properties, and therefore their corrosion rate needs to be controlled. The aim of this study is to select an appropriate environment where the effects of coatings on the corrosion rate of the underlying Mg alloy can be discerned and measured in a relatively short time period. The corrosion resistance of uncoated AZ31 alloy in different solutions [Hank's Balanced Salt Solution, 1× phosphate buffered solution (PBS), 4× PBS, 0.9%, 3.5%, and 5 M sodium chloride (NaCl)] was determined by measuring the weight loss over a 2 week period. Upon exposure to physiological solutions, the uncoated AZ31 alloys exhibited a variable weight increase of 0.4 ± 0.4%. 3.5% and 5 M NaCl solutions led to 0.27 and 9.7 mm/year corrosion rates, respectively, where the compositions of corrosion products from AZ31 in all saline solutions were similar. However, the corrosion of the AZ31 alloy when coated by electrochemical oxidation with two phosphate coatings, one containing fluorine (PF) and another containing both fluorine and silica (PFS), showed 0.3 and 0.25 mm/year corrosion rates, respectively. This is more than 30 times lower than that of the uncoated alloy (7.8 mm/year), making them promising candidates for corrosion protection in severe corrosive environments. Cross-sections of the samples showed that the coatings protected the alloy from corrosion by preventing access of saline to the alloy surface, and this was further reinforced by corrosion products from both the alloy and the coatings forming an additional barrier. The information in this paper provides a methodology for evaluating the effects of coatings on the rate of corrosion of magnesium alloys.

Bio-corrosion susceptibility of surface voids and pores in microwave sintered Ti-HAp based bio-composites

Deterioration of implants caused by human blood plasma and liquid influence is termed Bio-corrosion. It is detrimental for metal-based implants to function and affects their lifespan adversely. Hybrid-microwave sintered Titanium-Hydroxyapatite-based metal-ceramic composites were studied for corrosion behaviour in Hank's Balanced Salt solution using an electrochemical test in linear polarization potential mode. The sintering induces surface voids and pores, thus its influence on corrosion for Ti-HAp sintered composite was studied. Different corrosion characteristics were determined, and the corrosion sites were analyzed using SEM-EDS. The study could lead to the development of corrosion-resistant porous bio-implants under an actual physiological body-fluid environment.

Improvement of corrosion resistance and adhesion of hydroxyapatite coating on AZ31 alloy by an anodizing intermediate layer.

The primary objective of this study is using an anodizing intermediate layer to improve corrosion resistance and adhesion of hydroxyapatite coated AZ31 alloy for applications in biodegradable implants. An anodizing intermediate layer was formed on the surface of AZ31 substrate at various anodizing voltage of 10, 20, 30, and 40 V respectively by anodizing process. HAp was grow on the surface of AZ31 substrate at 90°C and pH solution of 7.5 by chemical solution treatment method for 2 h. The coated samples were evaluated their corrosion behavior by Electrochemical measurements and biodegradation behavior by immersion test in Hank's balanced salts solution (HBSS) for 28 days via amount of Mg2+ ion released. While, their adhesion strength were evaluated by pull-off method. The amount of Mg2+ ions released of the samples was quantified by the Inductively coupled plasma mass spectrometry. An anodizing intermediate layer was successfully synthesized at various voltages by anodizing process and HAp coatings were prepared by chemical solution treatment method. The corrosion rate of hydroxyapatite coated AZ31 alloy with an anodizing intermediate layer decreased 4.4 times, while adhesion strength increased about two times compared to the HAp coated AZ31 specimen without an anodizing layer and achieved ~14.70, ~6.92 MPa, respectively. After immersion test in HBSS, the adhesion strength of HAp/AZ31-HBSS-specimen decrease to 45% because of large corroded areas with depth holes of hundreds of micrometers. The slighter decrease in adhesion strength of HAp/30V/AZ31-HBSS-specimen to 22% is due to the contribution of the anodizing intermediate layer. HAp coated AZ31 alloy specimen with the existence of a porous structure with an elliptical shape, uniform and high density of MgO on the surface at anodizing voltage of 30 V resulted in a significant increase in corrosion resistance and the adhesion strength of HAp coatings.

Anticorrosive properties of chitosan-derivatives coatings on Mg AZ31 alloy in Hank's Balanced Salt Solution

This study describes the preparation of chitosan-derivatives coatings on AZ31 Mg alloy for corrosion protection in Hank's Balanced Salt Solution (HBSS). The derivatives were prepared by reacting chitosan with natural aldehydes (vanillin, benzaldehyde and cinnamaldehyde) and the coatings were characterized by means of water contact angle, scanning electron microscopy and swelling essays. The corrosion behavior of the samples was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy and hydrogen evolution essays. All derivatives present superior corrosion protection than neat chitosan and the best performance is observed for the vanillin derivative with the highest modification degree, which present hydrogen evolution rate of 0.05 mL cm−2 day−1, below the tolerance limit for biomedical application, and |Z|max in the order of 104.6 Ω cm2 even after 14 days of exposure to the corrosive solution.

Short-Term Storage of Japanese Koi (Cyprinus carpio var. koi) Sperm on the Egg Fertilization Performance

Lack of mature male broodfish, insufficient sperm, and non-synchronized maturation times have always been a hindrance to the breeding program of Japanese koi (Cyprinus carpio var. koi) raised indoors. Therefore, it is believed that the preservation of Japanese koi sperm by short-term storage and cryopreservation could solve this problem. In this study, the appropriate diluent solution, sperm-to-diluent ratio, and storage temperature for short-term storage of Japanese koi sperm were determined, and the efficacy of the short-term stored sperm in fertilizing eggs was evaluated. Milt samples collected from sexually mature males were pooled and tested in modified calcium-free Hank's Balanced Salt Solution (CF-HBSS), modified Mahseer extender, and modified Kurokura extender at 1:1 and 1:5 ratios of sperm to diluent, respectively. Storage temperatures were tested at 4 °C and room temperature. Milt sample without diluent solution served as a control. The percentage of sperm motility was measured daily for one week. For the egg fertilization experiment, Japanese koi eggs were fertilized with sperm on the second day of short-term storage, while a freshly collected sperm sample served as a control. We found that sperm diluted 1:1 with a modified Kurokura extender and stored at 4 °C had a mean sperm motility of 76.00 ± 3.06% on the third day, compared with 54.67 ± 2.91% in the control treatment (P&lt;0.05). Short-term stored spermatozoa showed equivalent egg fertilization ability compared to fresh spermatozoa (control) (P&gt;0.05). In conclusion, the use of a modified Kurokura extender at a 1:1 ratio of sperm to diluent and storage at 4 °C was optimal for short-term storage of Japanese koi sperm, and these sperm still showed equivalent egg fertilization ability to freshly collected sperm after two days of storage. In addition, the current study also determined the appropriate extender solution for cryopreservation of Japanese koi sperm.

Viability of periodontal ligament cells in selected transport media for avulsed teeth

To compare the viability of periodontal ligament (PDL) cells stored in Hanks Balanced Salt Solution (HBSS) with those in readily available transport media over a variable period of time. Methods: Periodontal ligament cells harvested from premolars freshly extracted for orthodontic reasons were cultured for exponential growth. The cells were exposed to egg white, evaporated milk, water and Hanks Balanced Salt Solution (HBSS) at room temperature. Their viability was evaluated after 30 minutes, 1 hour and 3 hours with the tetrazolium salt-based colorimetric assay (MTT assay). Statistical analysis was done using the IBM® SPSS version 23.0 software. Comparison between the Mean Optical Densities (MODs) of the cells stored in HBSS and other media at each time interval was done using the independent t test. Repeated measure ANOVA and Tukey post-hoc test were also carried out to compare the MOD of cells within each medium over time. The level of significance was set at p &lt;0.05. Result: The PDL cells stored in egg white had higher MODs than those in HBSS at 30 minutes and 1 hour. Conversely, the MODs of the cells stored in milk and water were lower than those in HBSS at all the studied points. There was a significant difference in the viability of the cells stored in HBSS and water at all the time points (p&lt;0.05). Conclusion: For up to an hour, egg white was found to perform better than HBSS in supporting the viability of PDL cells.

Effects of surface treatments of bioactive tricalcium silicate-based restorative material on the bond strength to resin composite

ObjectivesThis study aimed to enhance the bond strength between Biodentine™ (BD), a bioactive tricalcium silicate (C3S) based material, and resin composite through various surface treatments. MethodologyBD samples were immersed in either double distilled water or Hank's Balanced Salt Solution and analyzed using X-ray Diffraction (XRD). Shear bond strength (SBS) evaluations of BD were performed using Prime & Bond™ NT (PNT), Single Bond Universal (SBU), Xeno V (Xeno), and glass ionomer cement (GIC) following various etching durations (0 s/ 15 s/ 30 s/ 60 s with 37.5% phosphoric acid). Two primers, RelyX™ Ceramic Primer (RCP) and Monobond ™ Plus (MBP), were chosen to prime BD for SBS enhancement. Fractography and bonding interfaces were examined with energy dispersive X-ray spectroscopy (EDS)/ scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). ResultsXRD confirmed BD’s main compositions as C3S, Ca(OH)2, CaCO3 and ZrO2 after 14 days crystal maturation. Etched BD did not improve SBS. GIC exhibited the lowest SBS (p < 0.05) among all adhesives, regardless of the etching mode (all < 1 MPa). The highest SBS (17.5 ± 3.6 MPa, p < 0.05) was achieved when BD primed with MBP followed by SBU application. FTIR and EDS showed γ-MPTS and10-MDP within the MBP primer interacted with C3S and ZrO2 of BD, achieving enhanced SBS. Most specimens exhibited mixed or cohesive failure modes.SignificanceBD’s subpar mechanical properties and texture may contribute to its poor adhesion to resin composite. Pretreating BD with MBP primer, followed by SBU adhesive is recommended for improving bond strength.

Guttapercha Improves In Vitro Bioactivity and Dentin Remineralization Ability of a Bioglass Containing Polydimethylsiloxane-Based Root Canal Sealer.

Guttapercha (GP, trans-1,4-polyisoprene) is the most used tooth root filling material, and it must be used with an appropriate cement (typically a polydimethylsiloxane (PDMS)-based sealer) to ensure an adequate canal obturation. This study aimed to assess the bioactivity and dentin remineralization ability of a bioglass containing PDMS commercial endodontic sealer, BG-PDMS (GuttaFlow Bioseal), and to evaluate the possible influence of a GP cone (Roeko GP point) on the mineralization process. To this end, BG-PDMS disks were aged alone or in the presence of a GP cone in Hank's Balanced Salt Solution (28 d, 37 °C). Dentin remineralization experiments were carried out under the same conditions. Micro-Raman and IR analyses demonstrated that BG-PDMS is bioactive, thanks to the formation of a silica-rich layer with nucleation sites for B-type carbonated apatite deposition. This phase was thicker when BG-PDMS was aged in the presence of GP. The two materials influenced each other because GP, which alone did not show any bioactivity, nucleated a calcium phosphate phase under these conditions. Analogously, dentin remineralization experiments showed that BG-PDMS is able to remineralize dentin, especially in the presence of GP. Under the experimental conditions, GP acted as a templating agent for calcium phosphate deposition.

Zein-Bioactive Glass nanocomposite Coating on Magnesium Alloy Substrate for Orthopedic Applications

Excellent mechanical strength and biodegradable characteristics of magnesium alloys have sparked considerable interest in orthopedic applications. The utilization of magnesium alloys in orthopedic applications has been restricted due to their brittleness caused by high corrosion rate in biological environments. One of the best techniques for increasing corrosion resistance of these alloys is surface coating. For the first time, the present work aims to dip-coat zein-bioactive glass (BG) nanocomposite on AZ31B magnesium alloy. The alloy surface was also coated by native zein as a control coating. BG nanoparticles required for zein and BG (zein_BG) composite were synthesized by a bio-inspired method using cetyltrimethylammonium bromide (CTAB) as a template. The formation of BG particles was affirmed by FTIR showing characteristic Si-O-Si and Si-O– peaks. Nano-size of BG particles with an average diameter of 6.67 ± 0.06 nm was reported by TEM. SEM micrographs revealed successful deposition of zein and zein_BG coatings on the magnesium alloy surfaces. High-resolution XPS analysis on zein_BG-coated Mg alloy immersed in HBSS revealed the corrosion deposition of Mg(OH)2, MgHPO4.H2O, CaHPO4.H2O, SiO2, MgCO3, and CaCO3 on the substrate surface. More than twofold wettability, 95% adhesion strength and 14-fold increase in surface roughness were reported for zein_BG-coated magnesium alloy compared to the bare surface. Measurements of weight loss in zein and zein_BG-coated alloy substrates in Hanks Balanced Salt Solution (HBSS) for 10 d at 37°C showed a drastic decrease in weight loss of substrates after coating. As a result, zein_BG-coated substrate was observed to possess the maximum protective efficacy (95.99%) against corrosion. Interestingly, electrochemical measurements revealed a vast decrease in corrosion current density (2.41 E−6 A.cm−2) of zein_BG-coated substrate compared to the uncoated substrate (3.04 E−4 A.cm−2). Electrochemical impedance spectra (EIS) confirmed capacitive behavior of zein_BG-coated alloy substrate. These findings demonstrated that simple zein_BG composite dip coating was a successful corrosion-resistant implant coating on magnesium alloy surface for orthopedic applications.

The Comparative Analysis of the Effectiveness of Four Different Storage Media (Placentrex, Propolis 10%, Pomegranate Juice 5%, and Hank's Balanced Salt Solution) in Preserving the Viability of Periodontal Ligament Cells: An In Vitro Study.

Out of all traumas, dentoalveolar trauma occurs quite frequently and is commonly linked to avulsion injuries. Of all severe lesions to the permanent dentition, tooth avulsion accounts for 1%-16% of cases. The extraoral dry time and the storage medium in which the tooth is stored and its capacity to promote cell viability are two important variables influencing the prognosis of an avulsed tooth following replantation. The aim of this paper is to assess and contrast the effectiveness of placentrex, propolis 10%, pomegranate juice 5%, and Hank's balanced salt solution (HBSS) as a storage medium in preserving the periodontal ligament (PDL) cells' viability. Sixty freshly extracted premolars were put in four various media for 45 minutes each, including HBSS, placentrex, propolis 10%, and pomegranate juice 5%, and placed in an incubator for 30 minutes in 15 mL falcon tubes with 2.5 mL solutions of collagenase 0.2 mg/mL and dispase 2.4 mg/mL in phosphate-buffered saline. Bovine serum was added after incubation, and the mixture was centrifuged for four minutes. Trypan blue 0.4% wasused to identify the cells. Under a light microscope, a hemocytometerwasutilized to quantify the number of periodontal ligament cells that were still alive. Propolis, pomegranate, and placentrex are all significantly inferior to HBSS in the context of the sustainability of the cells. It was discovered that HBSS with placentrex and pomegranate juice 5% was statistically insignificant. The difference in periodontal ligament cell viability between propolis 10%, HBSS, placentrex, and pomegranate juice 5% was shown to be statistically significant. When compared to other media such as propolis 10% and pomegranate juice 5%, placentrex is a better alternative storage medium for avulsed teeth.

Effects of ethanol washing and storage duration on primary culture of stem cells from human exfoliated deciduous teeth

PurposeSince the oral environment harbors various microorganisms, the removal of contaminants during the primary culture process of stem cells from human exfoliated deciduous teeth (SHEDs) is very important. We investigated optimal methods for primary culture of SHEDs with minimal contamination rates. Materials and methodsThree different storage conditions for deciduous teeth were utilized:1) storing teeth in Hank's Balanced Salt Solution (HBSS) with 3% penicillin and streptomycin (P/S), 2) storing teeth in HBSS with 3% antibiotics and antimycotics (A-A), and 3) storing teeth in HBSS with A-A, and additional washing with 70% ethanol just before primary culture of dental pulp. In addition, the storage time from the extraction of teeth to the primary culture was measured. ResultsThe contamination rates were about 70% for HBSS with P/S, 40% for HBSS with A-A, and less than 10% for HBSS with A-A and additional washing with 70% ethanol. When the primary culture was conducted within 12 h after teeth extraction, the contamination rate was the lowest in all conditions. Furthermore, when the teeth were delivered in HBSS with A-A and an additional 70% ethanol washing was performed, the contamination rate was 0% until 48 h after teeth extraction. Ethanol washing had little effect on the cellular characteristics and stemness of SHEDs, including their morphology, growth rate, expression of surface markers, and differentiation potential. ConclusionsWe suggested that both delivering teeth in HBSS with A-A and additional 70% ethanol washing are critical considerations for the successful culture of SHEDs without contamination.

Optimisation of sperm cryopreservation protocol for Asian stinging catfish Heteropneustes fossilis (Bloch, 1794), to support hatchery seed production

The present study experimentally evaluated different parameters such as extender composition, storage duration and egg to sperm ratio to optimise parameters for sperm cryopreservation in Asian stinging catfish Heteropneustes fossilis. Four extender compositions viz. Hanks Balanced Salt Solution (HBSS), Modified HBSS (M-HBSS), Modified HBSS with hen’s egg yolk (M-HBSS with EY) and European catfish extender were evaluated for sperm cryopreservation with dimethyl sulphoxide (DMSO) as cryoprotectant (10% v/v). The hatching rate was used as standard to evaluate the fertility of thawed sperm at different periods of storage (2, 270 and 668 days). After 2 days, extender M-HBSS exhibited highest hatching rate (49.06±2.67%) which was comparable to the control value (51.00±7.23%), followed by HBSS (42.76±32.0%), M-HBSS with EY (37.46±24.34%) and European catfish extender (29.47±25.61%), respectively. After 270 days with M-HBSS, hatching rate was 64.34±8.84% similar to the control; however, cryopreserved sperm with other extenders exhibited lower hatching rate as compared to control and M-HBSS. After 668 days, sperm cryopreserved in the extender M-HBSS, only yielded successful hatching. Results indicated that presence of egg yolk in the extender M-HBSS did not improve the performance of cryopreserved sperm. The successful hatching using cryopreserved sperm after 270 and 668 days of storage indicates M-HBSS as a useful extender for sperm cryobanking and seed production of H. fossilis. Keywords: Aquaculture, Cryopreservation, Cryoprotectant, Dimethyl sulphoxide, Extender, Hanks Balanced Salt Solution, Hatching rate

Advancement in biological and mechanical behavior of 3D printed poly lactic acid bone plates using polydopamine coating: Innovation for healthcare

The metallic biomaterials have been proclaimed to exhibit stress shielding with discharge of toxic ions, leading to polymeric implants attracting interest in 3D Printing domain. In this study, Poly Lactic Acid based 336 bone plates are fabricated using Fused Filament Fabrication with printing parameters being varied. Polydopamine, being biocompatible, is deposited on fabricated bone plates at varying submersion time, shaker speed and coating solutions concentration. The study involves witnessing the effect of printing and coating parameters on biological behavior of bone plates upon preservation in Simulated Body Fluid and Hank's Balanced Salt Solution. The findings propose the close relation of degradation with apatite growth. The highest degradation rate with significant reduction in mechanical characteristics are shown by uncoated bone plates. These bone plates have porous structure at 20% infill density, 0.5 mm layer height, 0.4 mm wall thickness and 100 mm/s print speed which could result in complete degradation with partial healing of bone fracture. The study suggests the preservation of bone plates coated at 120 h' submersion time and 120 RPM shaker speed in 3 mg/ml concentrated solution which showed lower apatite formation. Thus, the coating would slow down degradation of PLA bone plates, resulting in complete healing of bone fracture.

Effects of Different CO2 Concentrations and Degradation Media on Static Corrosion of Commercially Pure Zinc

Zn alloys have lately captivated the attention of the scientific community as possible materials for cardiovascular applications, showing a corrosion behavior and mechanical properties in between of those of Mg and Fe alloys. To better understand the different aspects of the interaction of Zn with body fluids, the basic corrosion pattern and the degradation products’ formation were investigated considering the effect of CO2 amount in the atmosphere and different pseudo-physiological media; that is Hanks’ balanced salt (HSS), Dulbecco’s phosphate-buffered saline (PSS) and physiological saline solution (NSS), through a 14-day static immersion study. A mixed degradation layer mainly composed of ZnO with Zn3(PO4)2·4H2O and Zn(CO3)2 precipitates was found on surfaces immersed in both HSS and PSS, independently of the atmosphere, while a ZnO/ZnCl2 layer was found on the surface immersed in NSS, which also revealed the higher corrosion rate due to the effect of Cl− ions. Samples tested under a CO2-rich atmosphere showed a more compact passivating layer, higher dimensions crystals and less cavities when tested in HSS, PSS and NSS, respectively.

An In Vitro Evaluation of Morinda citrifolia and Ocimum sanctum as Potential Storage Media to Maintain Cell Viability for Avulsed Teeth Using Collagenase Dispase Assay.

Aim This study aimed to evaluate the protective effects of Ocimum sanctum extract and Morinda citrifolia juice on human periodontal ligament (PDL) cells after the reimplantation of avulsed teeth using a collagenase-dispase test. Materials and methods Sixty-five human premolars, all of which would eventually need to be extracted, were split into three experimental groups: one treated with Hanks Balanced Salt Solution, another with Morinda citrifolia juiceand Ocimum sanctum extract, and two control groups (positive and negative).There were 10 teeth in each control groupand 15 teeth each were used in the experimental groups, with the first 30 minutes spent dry before being submerged in one of three experimental media for 45 minutes, followed by 30 minutes of treatment with collagenase and dispase II. The cells' vitality was measured by the trypsin dye exclusion technique. To determine how many PDL cells were still alive, An optical microscope and a hemocytometer were used. The data were analyzed using Kruskal-Wallis one-way ANOVA and Mann-Whitney U tests. Results The percentage of viable PDL cells was greatest in Morinda citrifolia juice (85.18%), followed by HBSS (84.3%), and finally by Ocimum sanctum extract (68.04%). There was no significant difference in the number of viable PDL cells in Morinda citrifolia juice and HBSS. Conclusion The results of this research suggest that Morinda citrifolia juice has potential as a storage medium and as an alternative to HBSS, within the study's constraints, considering its availability as well as economic feasibility.