Photometric Monitoring of Electronic Cigarette Puff Topography.

To study and monitor the adverse health consequences of using electronic cigarettes, a user's puff topography, which are quantification parameters of the user's vaping habits, plays a central role. In this work, we introduce a topography sensor to measure the mass of total particulate matter generated in every puff and to estimate the nicotine yield. The sensor is compact and low-cost, and is integrated into the electronic cigarette device to promptly and conveniently monitor the user's daily puff topography. The topography sensor is comprised of a photometric sensor and a pressure sensor. The photometric sensor measures the mass concentration of the aerosol, based on scattering of near-infrared light from airborne particles, while the pressure sensor measures the flow rate. The topography sensor was tested under various conditions including a wide range of atomizer power, puff duration, and inhalation pressure. The sensor's accuracy was validated by comparing the sensor's readings with reference measurements, and the results matched closely with the trends reported by existing studies on electronic cigarettes. An example application for tracking a user's puff topography was also demonstrated. Our topography sensor holds great promise in mitigating the health risks of vaping, and in promoting quality control of electronic cigarette products.

Nebulization as a more efficient method than atomizer for experimental reproduction of avian colibacillosis in young chickens.

Infection and immunity studies involving genetically modified organisms (GMOs), such as gene knockout bacterial mutants, require stringent physical containment to prevent the accidental spread of these organisms into the environment. Experimental respiratory tract infection models often require the animals, for example birds, to be transported several times between a negative pressure housing isolator and a bespoke aerosol exposure chamber under positive pressure. While the exposure chamber is sealed and fitted with HEPA filters, the repeated movements of infected animals and opening of the chamber can still pose a serious risk of breaching containment of the organism in the experimental facility. In the current study, the ability of two aerosol infection protocols that expose birds to avian pathogenic E. coli (APEC) aerosols directly within the housing isolator was evaluated. Young chicks were exposed to APEC E956 within the negative pressure housing isolators using either a nebulizer or an atomizer. Birds exposed twice (days 1 and 4) to aerosols of APEC E956 produced by the nebulizer developed a rapidly progressing disease mimicking field cases of avian colibacillosis. However, birds exposed to aerosols of APEC E956 produced by an atomizer did not develop colibacillosis even after three exposures to APEC E956 on days 1, 4 and 7. Consequently, the current study reports the nebulizer was more efficacious in producing avian colibacillosis under stricter bacterial containment settings.RESEARCH HIGHLIGHTS Two aerosol exposure methods were evaluated to develop avian colibacillosis.Nebulizer method found to be more efficient in reproducing avian colibacillosis.Refined infection method can be used to study genetically modified organisms (GMOs).

Spray curtains as devices for surface spraying during the SARS-CoV-2 pandemic.

Counteracting the spread of the SARS-CoV-2 virus is a current and important problem. A crucial issue in this area is the disinfection of various surfaces, as well as the air itself. For this purpose, devices such as foggers, which have different designs, are used. The appropriate size of droplets and their distribution determines the effectiveness of disinfectants. The paper presents droplet size distributions and characteristic mean droplet diameters, which are obtained with the use of a conical pressure-swirl atomizer. For the purpose of the analysis, the laser diffraction method was used. The influence of gas pressure and the distance from the atomizer's orifice on the spray angle and the distance between the nozzles on the spray curtain was also demonstrated.

Study on a Flexible Odor-Releasing Device for Olfactory Training.

Olfactory training has been shown to be effective in treating olfactory dysfunction. However, there are hardly any devices that can regularly and quantificationally release odors for olfactory training. A new odor-releasing device, which is low-cost, customizable, semi-automatic, and flexible, was developed in this study. The operation of the device can be easily achieved by the examiner, or even by the participant, simply by pressing a few buttons. A controller system with 15 individual relays was employed to master the working logic for the whole process. The device allows the examiner to isolate from the participants using the Bluetooth module in the control board. The odorants and their concentrations stored in the scent bottles can be customized by the specific requirements of different participants. The odors for training are provided by ultrasonic atomizers, which have simple structures, but powerful features. The flow rates of the odors can also be controlled by altering the rotation speed of the fans. Final experiments on practical odor generation further proved the potential of the developed device for olfactory training. More attention should be paid to the improvements of odor generation devices for olfactory training.

Research on the Machinability of Micro-Tapered Hole Group in Piezoelectric Atomizer and the Improvement Method.

A metal atomizing sheet with a group of micro-tapered holes is the core constituent of a piezoelectric atomizer. However, the diameters of large-end and small-end micro-tapered holes in industrial applications deviate from the design values by 15.25% and 15.83%, respectively, which adversely impacts the effect of atomizers. In this study, two main factors that influence the machining quality of tapered holes, the external vibration disturbance and the internal system errors inside the laser processor, were explored; consequently, the vibration model of the machining device and the laser drilling model were established, respectively. Based on the models and the experimental results, it was found that the errors in diameter caused by these two factors accounted for 20% and 67.87% of the total deviation, respectively. Finally, an improved method was proposed, where a damping system was added to the machining device, and the diameter of the initial laser spot was corrected. The measurement results of tapered holes machined by the improved method showed that the deviation of the large diameters and the small diameters from the design values declined to 4.85% and 4.83%, respectively. This study lays a foundation for the high-precision and large-scale industry of atomizing sheets, and provides a new research direction for enhancing the performance of atomizers.

Comparison of the sedative effects of intranasal or intramuscular dexmedetomidine at low doses in healthy dogs: a randomized clinical trial.

OBJECTIVE: To compare the sedative effects of dexmedetomidine administered either intranasally or intramuscularly to healthy dogs. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A group of 16 client-owned healthy dogs. METHODS: Dogs were randomly allocated to one of two groups that were administered dexmedetomidine 5 µg kg-1 via either the intranasal route (INDex), through a mucosal atomization device in one nostril, or the intramuscular route (IMDex), into the epaxial muscles. Ease of intranasal administration, sedation score, onset of sedation, cardiopulmonary variables, mechanical nociceptive thresholds (MNTs) and response to venous catheterization were recorded at 0 (baseline), 5, 10, 15, 20, 25, 30, 35, 40 and 45 minutes, following drug administration. Data were compared with the one-way anova, Mann-Whitney U test, and chi-square test, where appropriate. RESULTS: Groups were not different for age, sex, weight, body condition score or temperament. Sedation scores, MNTs and response to intravenous catheter placement were not different when dexmedetomidine was administered by either route (p = 0.691; p = 0.630 and p = 0.435, respectively). Onset of sedation was not different between groups INDex and IMDex reaching a score of 4.2 ± 0.9 and 5.5 ± 1.2 at 9 ± 5 and 8 ± 4 minutes, respectively (p = 0.467). The highest sedation score was achieved at 30 and 35 minutes and sedation scores were 9.7 ± 2.0 and 9.5 ± 2.3 in groups INDex and IMDex, respectively (p = 0.799). Respiratory rate was higher in group INDex (p = 0.014), while there were no differences between routes in heart rate (p = 0.275), systolic (p = 0.957), diastolic (p = 0.837) or mean arterial pressure (p = 0.921). CONCLUSIONS AND CLINICAL RELEVANCE: Intranasal administration of dexmedetomidine at 5 µg kg-1 provides effective sedation in healthy dogs.

Effect of Montelukast sodium combined with Budesonide aerosol on airway function and T lymphocytes in asthmatic children.

Objectives: To investigate the effects of Montelukast sodium combined with Budesonide aerosol on airway function and T lymphocytes in asthmatic children. Methods: The records of 86 pediatric asthma patients, treated in Huzhou Maternal and Child Health Hospital from February 2020 to March 2021, were studied retrospectively. Of them, 40 children received routine treatment + budesonide atomizer (Group-I), and 46 patients received routine treatment + budesonide atomizer + montelukast sodium (Group-II). The improvement in airway and lung function, and T-lymphocyte count in both groups after 3 months of corresponding treatment were analyzed. Results: After three months of treatment, expiratory flow rate (TEF) with the tidal volume of 25%, 50% and 75%, was significantly higher in Group-II than Group-I (P<0.05). CD8+ expression in Group-II was lower, and CD3+, CD4+ and CD4+/CD8+ were higher than those in Group-I (P<0.05). There was a significant difference in the levels of inflammatory factors between the two groups. The levels of IL-4, IL-5 and IFN-γ in Group-II were lower than those in Group-I(P<0.05). Conclusions: In the clinical treatment of asthmatic children, in combination with routine treatment, budesonide atomizer and montelukast sodium can effectively promote the improvement of airway function, regulate T lymphocytes levels, reduce inflammatory reaction and improve the total clinical curative effect.

Utility of Three Nebulizers in Investigating the Infectivity of Airborne Viruses.

Laboratory-generated bioaerosols are widely used in aerobiology studies of viruses; however, few comparisons of alternative nebulizers exist. We compared aerosol production and virus survival for a Collison nebulizer, vibrating mesh nebulizer (VMN), and hydraulic spray atomizer (HSA). We also measured the dry size distribution of the aerosols produced and calculated the droplet sizes before evaporation and the dry size distribution from normal saline solution. Dry count median diameters of 0.11, 0.22, and 0.30 µm were found for normal saline from the Collison nebulizer, VMN, and HSA, respectively. The volume median diameters were 0.323, 1.70, and 1.30 µm, respectively. The effect of nebulization on the viability of two influenza A viruses (IAVs) (H1N1 and H3N2) and human rhinovirus 16 (HRV-16) was assessed by nebulization into an SKC BioSampler. The HSA had the least impact on surviving fractions (SFs) of H1N1 and H3N2 (89% ± 3% and 94% ± 2%, respectively), followed by the Collison nebulizer (83% ± 1% and 82% ± 2%, respectively). The VMN yielded SFs of 78% ± 2% and 76% ± 2%, respectively. Conversely, for HRV-16, the VMN produced higher SFs (87% ± 8%). Our findings indicate that there were no statistical differences between SFs of the viruses nebulized by these nebulizers. However, VMN produced higher aerosol concentrations within the airborne size range, making it more suitable where high aerosol mass production is required. IMPORTANCE Viral respiratory tract infections cause millions of lost days of work and physician visits globally, accounting for significant morbidity and mortality. Respiratory droplets and droplet nuclei from infected hosts are the potential carriers of such viruses within indoor environments. Laboratory-generated bioaerosols are applied in understanding the transmission and infection of viruses, modeling the physiological aspects of bioaerosol generation in a controlled environment. However, little comparative characterization exists for nebulizers used in infectious disease aerobiology, including Collison nebulizer, vibrating mesh nebulizer, and hydraulic spray atomizer. This study characterized the physical features of aerosols generated by laboratory nebulizers and their performance in producing aerosols at a size relevant to airborne transmission used in infectious disease aerobiology. We also determined the impact of nebulization mechanisms of these nebulizers on the viability of human respiratory viruses, including IAV H1N1, IAV H3N2, and HRV-16.

Analytical methods for the identification of micro/nano metals in e-cigarette emission samples: a review.

In this review, numerous analytical methods to quantify the heavy and trace elements emitted from electronic cigarettes, cigarettes liquid and atomizer. The selection of a method was dependent upon the purpose, e.g., quantification or identification of elements only. The introductory part of this review focuses on describing the importance of setting up an electronic cigarettes- associated safety profile. The review dealt with studies that assessed elements in sizes ranging from nano to micro. The formation of different degradation chemical substances as well as impurity trends can be indicated through chemical investigation of metals in electronic cigarettes. Some studies have been covered that show the uses and benefits of. It is noticeable from all the collected sources that the minerals emitted from the smoke of e- cigs do not constitute any significant damage, as the percentage is very small, with the exception of minerals that may be emitted from the components of the device after heating it if the components of the e- cig are of poor specifications, except in the case of long-term accumulation. For this reason, an electronic cigarette can help smokers to quit smoking tobacco and replace it with electronic cigarettes smoke with distinctive flavors.

Novel Approaches for Treating Pain in Children.

PURPOSE OF REVIEW: Good pain management in children, especially those at end of life, is a crucial component of palliative medicine. The current review assesses some of the new and/or innovative ways to manage pain in children. The article focuses on some recent medications/pharmaceutical options such as cannabinoids and also innovative ways to administer medication to children, such as intranasal and inhalation. RECENT FINDINGS: Current approaches to pain management now include (1) new uses of old drugs such as ketamine and lidocaine, (2) use of new drugs/medications such as cannabinoids, and (3) creative use of old technology such as atomizers, intranasal drops, and inhalation. Typically, novel approaches to care rarely start in pediatrics or palliative care. The current review has presented some new and old drugs being utilized in new and old ways.

Comparison of the sedative effects of medetomidine administered intranasally, by atomization or drops, and intramuscular injection in dogs.

OBJECTIVE: To compare the sedative effects of intranasal atomization (INA) of medetomidine with intranasal drops (IND) and intramuscular (IM) injection in healthy dogs. STUDY DESIGN: Prospective, blinded, randomized study. ANIMALS: A group of 18 mixed-breed shelter-owned dogs weighing 27 ± 4.3 kg (mean ± standard deviation). METHODS: The dogs were randomly assigned to equal groups of six dogs for administration of medetomidine (40 µg kg-1) by INA, IND and IM routes. Ease of administration was evaluated using a resistance scale. Composite sedation score (CSS), heart rate (HR) and respiratory frequency (fR) were measured immediately before (T0, baseline) and after drug administration at time points 15, 45, 75 and 120 minutes. The time of onset of sedation was recorded. Ease of administration and onset of sedation were analysed by the Kruskal-Wallis and post hoc Dunn's tests. Repeated measures analysis of anova and least significant difference tests were used to analyse CSS, HR and fR over time. Tukey's post hoc test was used for time point comparisons among groups. Significance was set at p < 0.05. RESULTS: No differences were detected among groups for ease of administration (p = 0.346). CSS increased in all groups from baseline values. Onset of sedation in IM was 6.3 ± 2.0 minutes, in INA was 7.2 ± 2.5 minutes and in IND was 20.7 ± 5.4 minutes. CSS in IND was lower than in the other groups at T15 and lower than in INA at T45. CSS was not different between IM and INA. HR and fR decreased in all groups compared with respective baseline values. HR in IND was lower than in IM at T45-T120. CONCLUSIONS AND CLINICAL RELEVANCE: INA medetomidine (40 µg kg-1) can be an alternative and noninvasive route to IM injections for sedating healthy dogs. IND resulted in a slow onset of sedation.

Surface Chemistry of Electronic Cigarette Electrical Heating Coils: Effects of Metal Type on Propylene Glycol Thermal Decomposition.

INTRODUCTION: Carbonyls, a class of compounds strongly linked to pulmonary disease in smokers, are probably the most reported non-nicotine toxicants found aerosols. Reported emissions vary from negligible quantities to those far exceeding combustible cigarettes. Observations of high emissions are commonly attributed to "dry puffing", whereby the ECIG heating filament runs dry of liquid and reaches temperatures that induce thermal degradation of the ECIG vapor components at the filament's metal surface. Using a pyrolysis flow reactor, in this study we examined the potential role of surface chemistry in the formation of carbonyl compounds in ECIGs, and whether the different commercially available filament materials could potentially impact their toxicant emissions through catalysis. This information could inform nascent efforts to regulate the design of ECIGs for public health ends. METHODS: Nitrogen or air saturated with propylene glycol vapor was drawn through a temperature and residence time controlled tubular quartz pyrolysis flow reactor in which nichrome, Kanthal, or stainless steel ECIG heating filament wires were inserted. A control condition with no inserted wire was also included. Concentrations of carbonyl products at the reactor outlet were measured as a function of temperature, heating filament wire material, and carrier gas composition (N2 vs air). Carbonyls were sampled using DNPH cartridges and analyzed by HPLC. RESULTS: ECIG heating filament wires were found to have a strong catalytic effect. Carbonyl formation initiated at temperatures lower than 250°C in the presence of the metallic wires, compared to 460°C without them. Carbonyl formation was found to be a function of the material of construction, and whether the wire was new or aged. New nichrome wires were the least reactive, but when aged they exhibited the highest reactivity. Carbonyls were formed via dehydration or oxidation reactions of PG. CONCLUSIONS: Carbonyl formation chemistry is catalyzed by commonly used ECIG heating filament materials, at temperatures that are well below those expected during "dry puffing". The variability in the distribution and yield of carbonyl compounds across ECIG filament materials suggests that this heretofore unaccounted variable may partially explain the wide ranges reported in the literature to date. More importantly, it suggests that ECIG construction materials may be an important variable for regulations designed to protect public health.

Update on Intranasal Medications in Rhinosinusitis.

This review describes beneficial effects and adverse events of various intranasal medications in treating rhinosinusitis. Application of intranasal steroids has been described in treating all subtypes of adult rhinosinusitis, but reports are limited in pediatrics and mostly in acute pediatric subgroups resulted in benefits While saline irrigation is effective for patients with chronic rhinosinusitis without polyps and in pediatric acute rhinosinusitis, there is no evidence yet for saline drips and sprays. Application of intranasal antifungals and nasal irrigation with surfactant brings more harm than benefits. There is no evidence supporting the use of intranasal antibiotics. We also review influence of devices, methods, and patient head position on nasal and paranasal sinus drug delivery.

A comparison of intranasal dexmedetomidine for sedation in children administered either by atomiser or by drops.

Intranasal dexmedetomidine has been used successfully for sedation in children. A mucosal atomisation device delivers an atomised solution to the nasal mucosa which facilitates rapid and effective delivery of medication to the systemic circulation. We compared intranasal delivery of dexmedetomidine in a dose of 3 µg.kg(-1) by either atomiser or drops from a syringe in children < 3 years old undergoing transthoracic echocardiography. Two hundred and seventy-nine children were randomly assigned to one or other group. One hundred and thirty-seven children received dexmedetomidine by atomiser and 142 by drops. The successful sedation rate was 82.5% (95% CI 75.3-87.9%) and 84.5% (95% CI 77.7-89.5%) for atomiser and drops, respectively (p = 0.569). Sedation tended to be less successful in older children (p = 0.028, OR 0.949, 95% CI 0.916-0.983). There were no significant complications. We conclude that both modes of dexmedetomidine administration are equally effective, although increasing age of the child was associated with a decreased likelihood of successful sedation.

Study on Anti-Inflammatory Effects of and Muscle Recovery Associated with Transdermal Delivery of Chaenomeles speciosa Extracts Using Supersonic Atomizer on Rat Model.

Repetitive motion or exercise is associated with oxidative stress and muscle inflammation, which can lead to declining grip strength and muscle damage. Oleanolic acid and ursolic acid have anti-inflammatory and antioxidant properties and can be extracted from Chaenomeles speciosa through ultrasonic sonication. We investigated the association between grip strength declines and muscle damage induced by lambda carrageenan (LC) injection and exercise exposure in rats. We also assessed the reparative effects of transdermal pretreatment and post-treatment with C. speciosa extracts (CSEs) by using a supersonic atomizer. The half-maximal inhibitory concentration (IC50) of CSEs for cells was 10.5 mg/mL. CSEs significantly reduced the generation of reactive oxygen species and inflammatory factors (interleukin [IL]-6 and IL-1ß) in in vitro cell tests. Rats subjected to LC injection and 6 weeks of exercise exhibited significantly increased inflammatory cytokine levels (IL-1ß, TNF-α, and IL-6). Hematoxylin and eosin staining revealed inflammatory cell infiltration and evident muscle damage in the gastrocnemius muscle, which exhibited splitting and the appearance of the endomysium and perimysium. The treated rats' grip strength significantly declined. Following treatment with CSEs, the damaged muscles exhibited decreased IL-1ß, TNF-α, and IL-6 levels and normal morphologies. Moreover, grip strength significantly recovered. Pretreatment with CSEs yielded an immediate and significant increase in grip strength, with an increase of 180% and 165% occurring in the rats exposed to LC injection and exercise within the initial 12 h period, respectively, compared with the control group. Pretreatment with CSEs delivered transdermally using a supersonic atomizer may have applications in sports medicine and training or competitions.

Enhanced skin neocollagenesis through the transdermal delivery of poly-L-lactic acid microparticles by using a needle-free supersonic atomizer.

In this study, a spindle-type nozzle was designed to accelerate poly-L-lactic acid (PLLA) microparticles to supersonic velocities for the transdermal delivery of these microparticles to rats. This approach is needle- and pain-free and enhances skin collagen regeneration. The addition of PLLA microparticles at a concentration of 2 mg/mL did not hinder the growth of 3 T3 fibroblasts and Raw264.7 macrophages. The TNF-α assay revealed no obvious inflammation effect of PLLA microparticles at a concentration of 1 mg/mL. A time-lapse recording revealed that after being cocultured with PLLA microparticles for 24 h, Raw264.7 macrophages gradually approached and surrounded the PLLA microparticles. When 3 T3 fibroblasts were cocultured with Raw264.7 macrophages, which were stimulated using PLLA microparticles, collagen synthesis was increased by approximately 60 % compared with that in samples without PLLA microparticles. In vivo animal experiments indicated that after the transdermal delivery of 10 shots of PLLA microparticles through the supersonic atomizer, no obvious changes or damage to the back skin of Sprague-Dawley rats was observed. More importantly, numerous PLLA microparticles penetrated the rat epidermis into the dermal layer. We found macrophages and fibroblasts present close to the PLLA microparticles. Moreover, only mild or no inflammation reaction was observed. Masson staining revealed that after 6-week implantation, 6 % and 12 % of PLLA microparticles significantly stimulated collagen regeneration in 6-week-old and 32-week-old rats. In addition, picrosirius red staining revealed a significant increase in collagen regeneration, especially for type III collagen, following the 6-week implantation of PLLA microparticles. In summary, this study demonstrated an easy, pain-free, nondestructive approach for introducing PLLA microparticles into the dermal layer by using a supersonic atomizer to stimulate collagen regeneration in vivo.

Multifunctional Ultrasmall Theranostic Nanohybrids Developed by Ultrasonic Atomizer for Drug Delivery and Magnetic Resonance Imaging.

Theranostic nanoparticulate systems (TNPs) have shown potential in addressing problems related to spatial localization and temporally controlled release of drugs with the capabilities of real-time imaging to evaluate the progress of therapy. The current study reports the ultrasonic atomization-led synthesis of in vitro and in vivo evaluations of ultrasmall chitosan-based theranostic nanohybrid formulations with encapsulated doxorubicin (DOX) and iron-oxide magnetic nanoparticles. The nanohybrid particles are characterized using transmission electron microscopy, powder X-ray diffraction, FTIR, DOX encapsulation efficiency, in vitro release, cellular uptake, and toxicity. These formulations were also tested for the capability of invivo tumor reduction and simultaneous magnetic resonance imaging using Swiss albino mice. Ultrasonic atomizer-led synthesis resulted in chitosan-magnetic nanohybrids (CMNPs) having sizes of 15 ± 3 nm which comprise MNP of 10 ± 3 nm. The encapsulation of DOX in CMNP was around 25%, resulting in an 80% sustained release over 10 days at pH 5 and 7. CMNP was also found to be an efficient DOX delivery vehicle tested on cancer cells (HeLa). The CMNPs were able to reduce the tumor volume by 60% in 15 days. The inherent magnetic property and nanoscale size of CMNPs also provided for enhanced contrast efficiency in magnetic resonance imaging of tumors. Thus, such multifunctional theranostic nanoparticles can be an efficient tool for targeted diagnostic and therapeutic success.

An effective solar assisted semi-cylindrical saline water desalination system with direct atomizer and energy storage materials for domestic use: an experimental investigation.

Solar still is the easiest method to purifying the saline water for domestic usage, but this method needs much improvement for better performance since it has lower productivity. In this paper, an experimental investigation is completed to analyse the semi cylindrical solar productivity still. The semi-cylindrical still is incorporated with direct atomizer and scrap used as an energy storage medium. Experiments are carried out during March 2020 in Kovilpatti, the southern part of India, with a depth of 2 and 4 cm saline water. Comparative performance analysis is made for conventional semi-cylindrical still, semi-cylindrical still with an atomizer, and semi-cylindrical still with atomizer and storage materials. The experimental study shows that the productivity of still increases while decreasing the water depth. Compared with 2-cm and 4-cm depth, solar still with 2-cm depth gives promising distillate productivity. The solar productivity still having 4-cm depth of water without atomizer gives only 2670 ml; on the other side, 2-cm water depth without atomizer gives 3100-ml productivity. The maximum productivity of solar still is found on a semi-cylindrical solar still combined with atomizer and energy storage medium having 2-cm water depth. Results revealed a higher freshwater production rate of 3610 ml found while incorporating atomizer and energy storage with the solar still. The system efficiency improved up to 35.20% compared to conventional semi-cylindrical still with 4 cm of saline water depth.

Phenotypic characteristics and protective efficacy of an attenuated Mycoplasma hyopneumoniae vaccine by aerosol administration.

With the improvement of large-scale breeding in pig farms, conventional head-by-head immunization has disadvantages with low efficiency and high cost. Considering that most pathogens leading to pulmonary diseases circulate from the respiratory mucosa, immunization through the respiratory tract route has been a highly attractive vaccine delivery strategy. In this study, to develop an effective Mycoplasma hyopneumoniae (Mhp) aerosol vaccine, a customized ultrasonic atomizer was developed. The aerodynamic diameter, activity, and content of the Mhp aerosol vaccine were measured. In addition, piglets were immunized with the Mhp aerosol vaccine, and the immunity of the animal challenge protection test was evaluated. At the end of nebulization, the mass median aerodynamic diameters (MMAD) and geometric standard deviation (GSD) of the aerosol were 2.98 ± 0.02 µm and 1.51 ± 0.02, respectively. Moreover, 10 min after nebulization, the MMAD and GSD of the aerosol were 2.76 ± 0.02 µm and 1.51 ± 0.01, respectively, which were hardly changed. Compared with theoretical value, the actual titer of aerosol vaccines presented in 50% color changing unit (CCU50) after nebulization decreased 0.6. The shape, size, and uniformity of collected aerosols are relatively stable. The proportion of Mhp in aerosol produced by vaccine stock solution and 10 times diluted vaccine solution was 76.52% and 58.82%, respectively, and the average number of Mhp in a single aerosol was 3.06 and 1.51, respectively. In addition, the aerosol vaccine antigen particles could be transported to the lower respiratory tract, a local mucosal immune response was induced in piglets. The vaccine colonized the respiratory tract and significantly decline the lung lesion index after aerosol vaccination. In conclusion, an effective aerosol vaccine against Mhp infection was developed. And this is the first effective assessment for Mhp live vaccine with aerosolization against infection in piglets.

Effervescent Atomizer as Novel Cell Spray Technology to Decrease the Gas-to-Liquid Ratio.

Cell spraying has become a feasible application method for cell therapy and tissue engineering approaches. Different devices have been used with varying success. Often, twin-fluid atomizers are used, which require a high gas velocity for optimal aerosolization characteristics. To decrease the amount and velocity of required air, a custom-made atomizer was designed based on the effervescent principle. Different designs were evaluated regarding spray characteristics and their influence on human adipose-derived mesenchymal stromal cells. The arithmetic mean diameters of the droplets were 15.4−33.5 µm with decreasing diameters for increasing gas-to-liquid ratios. The survival rate was >90% of the control for the lowest gas-to-liquid ratio. For higher ratios, cell survival decreased to approximately 50%. Further experiments were performed with the design, which had shown the highest survival rates. After seven days, no significant differences in metabolic activity were observed. The apoptosis rates were not influenced by aerosolization, while high gas-to-liquid ratios caused increased necrosis levels. Tri-lineage differentiation potential into adipocytes, chondrocytes, and osteoblasts was not negatively influenced by aerosolization. Thus, the effervescent aerosolization principle was proven suitable for cell applications requiring reduced amounts of supplied air. This is the first time an effervescent atomizer was used for cell processing.