Giant vesicles form in physiological saline and encapsulate pDNA by the modified electroformation method.

Giant vesicles (GVs) are used to study the structures and functions of cells and cell membranes. Electroformation is the most commonly used method for GV preparation. However, the electroformation of GVs is hindered in highly concentrated ionic solutions, limiting their application as cell models for research under physiological conditions. In this study, giant multilayer vesicles were successfully generated in physiological saline using a modified electroformation device by adding an insulating layer between the two electrode plates. The influence of the electric frequency and strength on the electroformation of GVs in physiological saline was explored, and a possible mechanism for this improvement was assessed. It has been shown that an insulating layer between the two electrodes can improve the electroformation of GVs in physiological saline by increasing the electrical impedance, which is weakened by the saline solution, thereby restoring the reduced effective electric field strength. Furthermore, macromolecular plasmid DNA (pDNA) was successfully encapsulated in the electroformed GVs of the modified device. This modified electroformation method may be useful for generating eukaryotic cell models under physiological conditions.

Buffalo yogurt fermented with commercial starter and Lactobacillus plantarum originating from breast milk lowered blood pressure in pregnant hypertensive rats.

Nutritional therapy, which may have advantages over medication, is being investigated as a novel treatment for pregnancy-induced hypertension. Several studies have shown that probiotic yogurt supplementation during pregnancy has beneficial effects on maternal and fetal health. In this study, fermented buffalo milk was produced with yogurt culture and Lactobacillus plantarum B, a probiotic isolated from healthy breast milk with high angiotensin-converting enzyme inhibitory activity. The fermentation conditions under which the angiotensin-converting enzyme (ACE) inhibitory activity reached 84.51% were optimized by the response surface method as follows: 2 × 106 cfu/mL of L. plantarum B, yogurt culture 2.5 × 105 cfu/mL, and 8 h at 37°C. The distribution of ACE inhibitory peptides from fermented buffalo milk and fermented cow milk were further analyzed by liquid chromatography-mass spectrometry. By searching according to the structural features of ACE inhibitory peptides, 29 and 11 peptides containing ACE inhibitory peptide features were found in fermented buffalo milk and fermented cow milk, respectively. To investigate the in vivo antihypertensive activity of fermented buffalo milk, 18 pregnant rats were divided into 3 groups (n = 6 in each group) and administered 10 mL of normal saline, yogurt (20 mg/kg), or labetalol hydrochloride (4 mg/kg) daily from the beginning of pregnancy to parturition. To induce hypertension, methyl nitrosoarginine (125 mg/kg) was injected subcutaneously every day from d 15 of pregnancy to the day of delivery. Blood pressure was not significantly changed in the yogurt and labetalol groups after induction of hypertension and was lower compared with the normal saline group, but there was no difference between the yogurt and labetalol groups. This implied that the buffalo yogurt had a preventive and antihypertensive effect in the pregnancy-induced hypertensive rat model. Further studies to determine the mechanism of action, as well as a randomized control trial, are warranted.

Phytochemical prospection, hemagglutinating and insecticidal activity of saline extracts from the seeds of Tamboril (Enterolobium contortisiliquum) Vell. Morong (Fabaceae) on Aedes aegypti (Diptera: Culicidae).

This study evaluated the insecticidal activity of crude extracts from Enterolobium contortisiliquum (Vell.) seeds on eggs and larvae of A. aegypti, and also verified the phytochemical profile and the presence of lectins in the extract. The 0.15 M NaCl saline solution was used as the extracting substance. For tests with eggs and larvae, the crude extract was used in its raw form (RCE) and boiled at 100º C for 5 min (BCE). Concentrations of 4.68; 9.37; 18.75; 28.13; 37.13 and 46.89 mg/mL, with distilled water as a negative control. Assays were performed in triplicate. The results were subjected to analysis of variance, Tukey's test and Log-Probit analysis to determine LC50 and LC90. BCE showed better results on eggs than RCE, managing to prevent the hatching of larvae in 81.66% ± 10.40 of treated eggs, at a concentration of 46.89 mg/mL. The LC50 and LC90 were set at 35.95 and 52.67 mg/mL, respectively. In tests with larvae, concentrations of 46.89 and 37.13 mg/mL, for RCE and BCE, caused 100% mortality in 24 hours of exposure. Larval mortality at the other concentrations increased with exposure time extending to 48 h. RCE, at 48 h exposure is the most promising extract on larvae (E = 72.77%, LC90 = 10.86 mg/mL). In RCE, the presence of lectins and secondary metabolites: flavonoids, xanthones and phenols, were detected. The results demonstrate the potential of E. contortisiliquum seed extracts with ovicidal and larvicidal action on A. aegypti.

Maintenance of sterility in SMS packaging in dental environments: concern with biosafety

Healthcare services must be guided by biosafety practices and microbial control. This control is highly influenced by humidity, which directly impacts the maintenance of sterility of the materials used in the appointments. High concentration of moisture, in the form of aerosol, splashes and spills, is caused during dental care. During the COVID-19 times the contamination by aerosol and droplets worries greatly. Considering that it could cause harm to the sterility of an autoclaved material, especially in dental environments, the objective was to evaluate the behavior of SMS sterilization packages (Spunbonded / Meltblown / Spunbonded) against microbial penetration in an aqueous vehicle. SMS of three brands were challenged, equally divided into two groups: virgin and processed (subjected to a single autoclaving cycle). Each specimen was aseptically deposited on Macconkey agar. Subsequently, 5 µL of Escherichia coliATCC 25922 saline solution [108CFU mL-1] was deposited in center of the SMS specimen and the dish incubated at36°C/ 48h. Reading was performed by the presence or absence of bacterial growth typical of the species under the SMS, observed on the back of Petri dish. The lowest penetration rate observed was 60% for one of the brands in the virgin condition, and 75% for two brands in the processed condition. Statistical analysis showed an association between bacterial penetration and the evaluated group, this association being valid only in the virgin condition. The different SMS behave similarly in terms of resistance to bacterial penetration after being processed. The data show that moisture can assist in bacterial transport through sterilized SMS. Therefore, SMS packages are not able to prevent bacterial penetration, and possibly other microorganisms, when in aqueous vehicles, offering a potential risk of breaking the aseptic chain. Thus, care must be taken in routines for handling and storage sterile packaging.

Compatible stability of methylprednisolone sodium succinate and tropisetron in 0.9% sodium chloride injection.

Background: A combination of methylprednisolone sodium succinate and tropisetron hydrochloride is commonly used to treat the nausea and vomiting associated with antineoplastic therapy. The objective of this study was to investigate the stability of tropisetron hydrochloride and methylprednisolone sodium succinate in 0.9% sodium chloride injection for up to 48 hours. Methods: Commercial solutions of methylprednisolone sodium succinate and tropisetron hydrochloride were obtained and further diluted with 0.9% sodium chloride injection to final concentrations of either 0.4 or 0.8 mg/mL (methylprednisolone sodium succinate) and 0.05 mg/mL (tropisetron). The admixtures were assessed for periods of up to 48 hours after storage at 4°C with protection from light and at 25°C without protection from light. Physical compatibility was determined visually, and the chemical compatibility was measured with high-performance liquid chromatography (HPLC) and by measurement of pH values. Results: HPLC analysis demonstrated that methylprednisolone sodium succinate and tropisetron hydrochloride in the various solutions were maintained at 97% of the initial concentrations or higher during the testing period. There were no changes observed by physical precipitation or pH in any of the prepared solutions. Conclusions: Tropisetron hydrochloride injection and methylprednisolone sodium succinate injection in 0.9% sodium chloride injection are stable for up to 48 hours at 4°C and 25°C.

Retinal-based polyene fluorescent probe for selectively detection of Cu2+ in physiological saline and serum.

Retinal is a flexible natural chromophore and widely present in organisms. The slender conjugated polyene structure retinal is conducive to entering protein structure. In this work, a novel turn-on fluorescent probe for Cu2+ based on retinal and phenylenediamine was designed and synthesized. The probe achieved recognition of copper ions in human serum complex protein environment. Furthermore, the high sensitivity, selectivity for Cu2+ and the sensing mechanism was also investigated.

A novel 3D-printed solid phase microextraction device equipped with silver-polyaniline coated pencil lead for the extraction of phthalate esters in cosmeceutical products.

A screw-based portable and simple solid phase microextraction device was fabricated by a 3D printer and used in combination with the developed silver-incorporated porous polyaniline film pencil lead solid-phase microextraction fiber (Ag/PANI SPME). Scanning electron microscopy revealed a porous structure of the electrodeposited Ag/PANI film. The spectrum from energy dispersive x-ray spectroscopy (EDS) and the elemental map confirmed the presence of silver in the porous polymer film. It was used under stirring for the extraction of five phthalate esters: dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), benzyl butyl phthalate (BBP) and di-2-ethylhexyl phthalate (DEHP). The extracted solution was identified and quantified by gas chromatography using a flame ionization detector (GC-FID). Under the optimum conditions of the developed method, a good linearity was obtained in a concentration range of 5.0-1000 µg L-1 for all five phthalate esters with limits of detection (LODs) of 4.41 ±â€¯0.91 µg L-1, 3.98 ±â€¯0.92 µg L-1, 3.65 ±â€¯0.74 µg L-1, 4.91 ±â€¯0.52 µg L-1 and 4.25 ±â€¯0.66 µg L-1 for DMP, DEP, DBP, BBP and DEHP, respectively. The developed method provided good precision when tested with standard solutions (RSD < 5.5%, n = 6) and real samples (RSD < 3.4%, n = 6). Good fiber-to-fiber reproducibility was also confirmed by extraction with six newly prepared fibers; recoveries ranged from 81.09 ±â€¯0.54% to 92.92 ±â€¯0.46% with RSD <6.6%. The developed method was used to determine phthalate esters in 14 cosmeceutical samples. In rubbing alcohol samples, DEP and DEHP were detected at 7.03 ±â€¯0.76 µg L-1 and 5.89 ±â€¯0.53 µg L-1, respectively, while in contact lens cleaners, DEHP was found in a concentration range from 5.3 ±â€¯1.1 µg L-1 to 6.8 ±â€¯1.2 µg L-1. No phthalate esters contamination was detectable in saline solutions, eye cleaners and antibacterial disinfectant liquids. Recoveries in the range of 81.92 ±â€¯0.99% to 102.4 ±â€¯1.1% indicated the good accuracy of the developed method.