A locus coeruleus to dorsal hippocampus pathway mediates cue-induced reinstatement of opioid self-administration in male and female rats.

Opioid use disorder is a chronic relapsing disorder encompassing misuse, dependence, and addiction to opioid drugs. Long term maintenance of associations between the reinforcing effects of the drug and the cues associated with its intake are a leading cause of relapse. Indeed, exposure to the salient drug-associated cues can lead to drug cravings and drug seeking behavior. The dorsal hippocampus (dHPC) and locus coeruleus (LC) have emerged as important structures for linking the subjective rewarding effects of opioids with environmental cues. However, their role in cue-induced reinstatement of opioid use remains to be further elucidated. In this study, we showed that chemogenetic inhibition of excitatory dHPC neurons during re-exposure to drug-associated cues significantly attenuates cue-induced reinstatement of morphine-seeking behavior. In addition, the same manipulation reduced reinstatement of sucrose-seeking behavior but failed to alter memory recall in the object location task. Finally, intact activity of tyrosine hydroxylase (TH) LC-dHPCTh afferents is necessary to drive cue induced reinstatement of morphine-seeking as inhibition of this pathway blunts cue-induced drug-seeking behavior. Altogether, these studies show an important role of the dHPC and LC-dHPCTh pathway in mediating cue-induced reinstatement of opioid seeking.

Assessment of novel antiviral filter using pseudo-type SARS-CoV-2 virus in fast air velocity vertical-type wind tunnel.

Current evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can remain suspended spread in aerosols for longer period of time under poorly ventilated indoor setting. To minimize spreading, application of antiviral filter to capture infectious aerosols and to inactivate SARS-CoV-2 can be a promising solution. This study aimed to develop a method to assess simultaneously the filtration and removal efficiency of aerosolized pseudo-type SARS-CoV-2 using a vertical-type wind tunnel with relatively high face velocity (1.3 m/s). Comparing with the untreated spunlace non-woven filter, the C-POLAR™ treated filter increased the filtration efficiency from 74.2 ± 11.5% to 97.2 ± 1.7%, with the removal efficiency of 99.4 ± 0.051%. The results provided not only solid evidence to support the effectiveness of the cationic polymeric coated filter in fighting against the SARS-CoV-2 pandemic, but also a method to test viral filtration and removal efficiency under relative fast air velocity and with a safer environment to the operators.

Oral Vaccines: A Better Future of Immunization.

Oral vaccines are gaining more attention due to their ease of administration, lower invasiveness, generally greater safety, and lower cost than injectable vaccines. This review introduces certified oral vaccines for adenovirus, recombinant protein-based, and transgenic plant-based oral vaccines, and their mechanisms for inducing an immune response. Procedures for regulatory approval and clinical trials of injectable and oral vaccines are also covered. Challenges such as instability and reduced efficacy in low-income countries associated with oral vaccines are discussed, as well as recent developments, such as Bacillus-subtilis-based and nanoparticle-based delivery systems that have the potential to improve the effectiveness of oral vaccines.

Quantitative analysis and risk assessment to full-size microplastics pollution in the coastal marine waters of Hong Kong.

Given the potential risk to the ecosystem, attention has increased in recent decades to the contamination of the aquatic environment by microplastics (MPs). Due to the limitations of conventional analysis methods of MPs, little is known about the size distribution and abundance of a full-size MPs from 1 µm to 5 mm. The present study quantified MPs with size ranges of 50 µm - 5 mm and 1-50 µm in the coastal marine waters from twelve locations in Hong Kong using fluorescence microscopy and flow cytometry respectively, during the end of wet (September 2021) and dry (March 2022) seasons. The average abundance of MPs with size ranges of 50 µm - 5 mm and 1-50 µm from twelve sampling locations marine surface waters were found ranging from 27 to 104 particles L-1 and 43,675-387,901 particles L-1 in the wet season respectively, and 13-36 particles L-1 and 23,178-338,604 particles L-1 in the dry season respectively. Significant temporal and spatial variations of small MPs abundance might be observed at the sampling locations, which were contributed by the influences of the estuary of Pearl River, sewage discharge points, land structure, and other anthropogenic activities. Based on the MPs abundance information, ecological risk assessment was conducted and revealed that the small MPs (< 10 µm) in coastal marine surface waters may pose potential health risks to aquatic organisms. Additional risk assessments are needed in order to determine whether or not the MPs exposure would cause health risks to the public.

Development of Method for Evaluation of Edible Bird's Nest Content in Ready-to-Eat Beverages.

BACKGROUND: Edible bird's nest (EBN) is one of the most valuable tonic Chinese foods, made from glutinous salivary secretion with highly concentrated mucin glycoprotein. For ease of consumption, manufacturers have marketed different ready-to-eat EBN products, in which the EBN content varies. This is the first study to analyze the EBN content in ready-to-eat beverages. OBJECTIVE: To determine the EBN content in ready-to-eat beverages by its active ingredient, N-acetylneuraminic acid (sialic acid). METHOD: Sialic acid in ready-to-eat beverages and raw EBN was extracted in sodium hydrogen sulfate solution, followed by derivatization using o-phenylenediamine dihydrochloride and determination using high-performance liquid chromatography (HPLC). Method precision, recovery of extraction, degradation of sialic acid due to cooking, and measurement uncertainty were evaluated. RESULTS: The mean concentrations of raw EBN in different origins and colors ranged from 5.77 to 10.92%. Ten different brands of traditional ready-to-eat EBN beverages from the market were analyzed, in which estimated concentrations of EBN were diversified, ranging from 0.014 ± 0.010 to 0.66 ± 0.069% (w/w) (95% confidence level). The concentration of sialic acid was found to range from 11.4 to 527 mg/kg. CONCLUSIONS: Based on the results, sialic acid content can provide a better estimation of the EBN content in traditional ready-to-eat beverages. Neither the selling price nor dried matter could be used as an indicator of the quality of the ready-to-eat EBN beverage among the samples obtained. HIGHLIGHTS: Sialic acid can be used as an indicator to estimate EBN content, where the sialic acid and EBN content in ready-to-eat beverages from the market were found to vary significantly.

Retraction: Sung et al. Expression of SARS-CoV-2 Spike Protein Receptor Binding Domain on Recombinant B. subtilis on Spore Surface: A Potential COVID-19 Oral Vaccine Candidate. Vaccines 2022, 10, 2.

The journal retracts the article "Expression of SARS-CoV-2 Spike Protein Receptor Binding Domain on Recombinant B. subtilis on Spore Surface: A Potential COVID-19 Oral Vaccine Candidate"[...].

Quantitative Assessment of Full Size Microplastics in Bottled and Tap Water Samples in Hong Kong.

Human exposure to microplastics (MPs) through drinking water has drawn serious concern recently because of the potential adverse health effects. Although there are reports on the occurrence of MPs in bottled water, little is known about the abundance of a whole spectrum of MPs with sizes ranging from 1 µm to 5 mm due to the restrictions of conventional MPs detection methods. Some studies using micro-Raman spectroscopy can achieve MPs with a size of <10 µm, however, quantitation of all MPs was extremely time consuming and only a small portion (<10%) of MPs would be analyzed. The present study quantified MPs from nine brands of bottled water using fluorescence microscopy and flow cytometry for MPs with a size of ≥50 µm and a size of <50 µm, respectively. The average abundance of MPs with a size of ≥50 µm in bottled water samples was found ranging from 8-50 particles L-1, while MPs with a size of <50 µm were found to be 1570-17,817 particles L-1, where the MPs abundance from mineral water samples were significantly more than distilled and spring water samples. The modal size and shape of MPs were found at 1 µm and fragments, respectively. Besides, three tap water samples obtained locally were analyzed and compared with the bottled water samples, where less MPs were found in tap water samples. In addition, contamination of MPs from bottle and cap and interference by addition of mineral salts were studied, where no significant difference from all these processes to the control sample was found, suggesting the major contamination of MPs was from other manufacturing processes. Estimated daily intake (EDI) of MPs increased substantially when data of small MPs are included, suggesting that previously reports on exposure of MPs from drinking water might be underestimated, as only large MPs were considered.

Safety and Immunogenicity of Inactivated Bacillus subtilis Spores as a Heterologous Antibody Booster for COVID-19 Vaccines.

The coronavirus diseases 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have threatened the world for more than 2 years. Multiple vaccine candidates have been developed and approved for emergency use by specific markets, but multiple doses are required to maintain the antibody level. Preliminary safety and immunogenicity data about an oral dose vaccine candidate using recombinant Bacillus subtilis in healthy adults were reported previously from an investigator-initiated trial in Hong Kong. Additional data are required in order to demonstrate the safety and efficacy of the candidate as a heterologous booster in vaccinated recipients. In an ongoing, placebo-controlled, observer-blinded, fixed dose, investigator-initiated trial conducted in the Macau, we randomly assigned healthy adults, 21 to 62 years of age to receive either placebo or a Bacillus subtilis oral dose vaccine candidate, which expressed the spike protein receptor binding domain of SARS-CoV-2 on the spore surface. The primary outcome was safety (e.g., local and systemic reactions and adverse events); immunogenicity was a secondary outcome. For both the active vaccine and placebo, participants received three courses in three consecutive days. A total of 16 participants underwent randomization: 9 participants received vaccine and 7 received placebo. No observable local or systemic side-effect was reported. In both younger and older adults receiving placebo, the neutralizing antibody levels were gradually declining, whereas the participants receiving the antibody booster showed an increase in neutralizing antibody level.

Expression of SARS-CoV-2 Spike Protein Receptor Binding Domain on Recombinant B. subtilis on Spore Surface: A Potential COVID-19 Oral Vaccine Candidate.

Various types of vaccines, such as mRNA, adenovirus, and inactivated virus by injection, have been developed to prevent SARS-CoV-2 infection. Although some of them have already been approved under the COVID-19 pandemic, various drawbacks, including severe side effects and the requirement for sub-zero temperature storage, may hinder their applications. Bacillus subtilis (B. subtilis) is generally recognized as a safe and endotoxin-free Gram-positive bacterium that has been extensively employed as a host for the expression of recombinant proteins. Its dormant spores are extraordinarily resistant to the harsh environment in the gastrointestinal tract. This feature makes it an ideal carrier for oral administration in resisting this acidic environment and for release in the intestine. In this study, an engineered B. subtilis spore expressing the SARS-CoV-2 spike protein receptor binding domain (sRBD) on the spore surface was developed. In a pilot test, no adverse health event was observed in either mice or healthy human volunteers after three oral courses of B. subtilis spores. Significant increases in neutralizing antibody against sRBD, in both mice and human volunteers, after oral administration were also found. These findings may enable the further clinical developments of B. subtilis spores as an oral vaccine candidate against COVID-19 in the future.

Application of anaerobic bacterial ammonification pretreatment to microalgal food waste leachate cultivation and biofuel production.

Food waste constitutes the largest component of municipal solid waste in many urbanized societies. The current practice of disposing of biodegradable food waste mixed with other solid wastes to landfills is not sustainable and is environmentally undesirable. Moreover, the leakage of nutrient-rich food waste leachate (FWL) impacts the environment by eutrophication of the water body. Two robust microalgal species, Dunaliella tertiolecta (D. tertiolecta) and Cyanobacterium aponinum (C. aponinum), have been selected previously for the treatment of FWL because they can tolerate diluted FWL. However, growth suppression by some inhibiting factors, such as total suspended solids and organic nitrogen, limited biomass productivity, and substantial dilution (5-10% v/v FWL) was required. To alleviate this suppression, anaerobic bacterial digestion was proposed to pretreat FWL and convert certain nutrients such as organic nitrogen to ammonium. The pretreatment was optimized in neutral to slightly alkaline media, where a byproduct of biomethane up to 4.67 L methane/kg COD was produced. In addition, digestate after anaerobic ammonification can provide sufficient inorganic nutrients for subsequent microalgal biofuel production. Through batch cultivation, 50% (v/v) of anaerobic bacterial pretreated FWL digestate can be fed to D. tertiolecta, with biomass productivity of up to 0.88 g/L/day, and biomass productivity can be increased to 0.34 g/L/day for C. aponinum at 30% FWL digestate. Regarding the nutrient removal efficiency, 98.99% of total nitrogen and 65% of total phosphorus can be removed by D. tertiolecta, whereas more than 80% of total nitrogen and 65% of total phosphorus can be removed by C. aponinum. The use of anaerobic bacterial ammonification pretreatment can significantly improve the performance of subsequent microalgal treatments and has been shown to be a sustainable green technology for biofuel production and FWL recycling.

Reduction in biogenic amines in douchi fermented by probiotic bacteria.

Ecology studies showed that esophageal and gastric cancers are directly correlated with the consumption of processed foods. The carcinogenicity of traditional Chinese fermented foods such as douchi (fermented black beans or fermented black soybeans) is due to the presence of carcinogenic N-nitroso compounds, which are derived from biogenic amines. Among the various biogenic amines that can act as precursors of N-nitroso compounds, histamine and tyramine are considered to be the most toxic and are of public health concern when present in food. We have examined some douchi products on the market, and significant amounts of histamine and tyramine were found. The use of fermentation starters generated by subculturing fermented products with unknown microbiota would induce the risk of biogenic amines. As the microbiota used in fermentation is a crucial factor in determining the biogenic amines of fermented food, it is hypothesized that the possible harmful effects of douchi can be minimized through the use of fermentation starters composed of probiotic bacteria. This is the first study to investigate the potential of using probiotic bacteria in manufacturing douchi. Lactobacillus rhamnosus GG (LGG), Lactobacillus casei Shirota (LcS) and Escherichia coli Nissle 1917 (EcN) were used to ferment black beans in this study, and no tyramine was detected in black bean samples incubated with these three strains anaerobically at 37°C or 20°C. The starter culture strains, temperature and presence of oxygen during the incubation period were found to be critical to the generation of biogenic amines. The findings of this study can provide evidence-based insights and warrant further investigations on the potential of reducing the harmful compounds in food fermented with probiotic bacteria as well as the sensory evaluation of douchi fermented with probiotic bacteria.

Mechanisms and therapeutic strategies for non-T2 asthma.

Non-T2 asthma is traditionally defined as asthma without features of T2 asthma. The definition is arbitrary and is generally based on the presence of neutrophils in sputum, or the absence (or normal levels) of eosinophils or other T2 markers in sputum (paucigranulocytic), airway biopsies or in blood. This definition may be imprecise as we gain more knowledge from applying transcriptomics and proteomics to blood and airway samples. The prevalence of non-T2 asthma is also difficult to estimate as most studies are cross-sectional and influenced by concomitant treatment with glucocorticosteroids, and by the presence of recognized or unrecognized airway infections. No specific therapies have shown any clinical benefits in patients with asthma that is associated with a non-T2 inflammatory process. It remains to be seen if such an endotype truly exists and to identify treatments to target that endotype. Meanwhile, identifying intense airway neutrophilia as an indicator of airway infection and airway hyperresponsiveness as an indicator of smooth muscle dysfunction, and treating them appropriately, and not increasing glucocorticosteroids in patients who do not have obvious T2 inflammation, seem reasonable.

Optimization of protein extraction and two-dimensional gel electrophoresis profiles for the identification of Cordyceps sinensis and other similar species.

Given that Chinese materia medica (CMM) is expensive and rare, people take tremendous risk to adulterate and falsify Cordyceps sinensis with counterfeit species with similar morphological features. It is thus essential to develop new methods to identify the authenticity of Cordyceps sinensis. It is hypothesized in this study that Cordyceps sinensis possesses certain protein biomarkers distinct from its counterfeits, which can be identified by proteomic technologies for authentication purposes. This is the first study that aims to optimize the conditions for extracting proteins from Cordyceps sinensis, a hybrid of fungal-animal CMM, and to compare the two-dimensional gel electrophoresis (2-DE) profiles between different Cordyceps species. Two different protein extraction buffer systems, namely, phenol/sodium dodecyl sulfate (SDS) buffer or lysis buffer, were evaluated, where the preparation using lysis buffer yielded better protein content. The results also showed that extraction with lysis buffer without pre- or post-washing of samples was the most effective protocol, with over 220% of protein yield and 819 protein spots detected on a 2-DE gel. Moreover, the results demonstrated that Cordyceps sinensis possesses protein biomarkers distinct from its counterfeits, and these biomarkers are not source- or origin-dependent, strongly supporting the feasibility of using identified biomarkers as indicators for authentication of Cordyceps species. The findings of this study warrant further investigations on the structural identification of protein biomarkers of Cordyceps species.

Evaluation of the Use of TRIzol-Based Protein Extraction Approach for Gel-Based Proteomic Analysis of Dried Seafood Products and Chinese Tonic Foods.

Although the emergence of gel-free approaches has greatly enhanced proteomic studies, two-dimensional gel electrophoresis (2-DE) remains one of the most widely used proteomic techniques for its high resolving power, relatively low cost, robustness, and high resolution. Preparation of high-quality protein samples remains the key in high-quality 2-DE for proteomic analysis. Samples with high endogenous levels of interfering molecules, such as salts, nucleic acids, lipids, and polysaccharides, would yield a low-quality 2-DE gel and hinder the analysis. Recently, a TRIzol-based protein extraction method has gained prominence and has attracted attention due to its promising performance in high-quality 2-DE. The authors evaluate the use of this approach for four valuable dried food products, namely two dried seafood products (abalone slices and whelk slices) and two traditional Chinese tonic foods (ganoderma and caterpillar fungus). The results indicate that 2-DE gels obtained through the TRIzol-based method are of high-quality and are comparable to those obtained through the trichloroacetic acid⁻acetone method in terms of spot number, spot intensity, and resolution. The TRIzol-based method is generally applicable to dried food samples and is simple and fast, which greatly streamlines the protein extraction procedure. Additionally, it enables the concurrent extraction and analysis of RNA, DNA, and protein from the same sample.

Highly Chlorinated, Brominated, and Iodinated Icosahedral Carborane Anions: 1-H-CB(11)X(11)(-), 1-CH(3)-CB(11)X(11)(-) (X = Cl, Br, I); 1-Br-CB(11)Br(11)(-).

Direct chlorination of 1-CH(3)-CB(11)H(11)(-) in glacial acetic acid gave the highly chlorinated carborane anion 1-CH(3)-CB(11)Cl(11)(-), and treatment of 1-CH(3)-CB(11)H(11)(-) with ICl in triflic acid afforded the highly iodinated carborane anion 1-CH(3)-CB(11)I(11)(-). Under similar or more vigorous reaction conditions, however, the reaction of 1-CH(3)-CB(11)H(11)(-) with Br(2) in triflic acid did not proceed to completion. The highly brominated carborane anion 1-CH(3)-CB(11)Br(11)(-) was achieved via a sealed-tube reaction. This new method has led to the isolation of 1-H-CB(11)X(11)(-) (X = Cl, Br, I) and 1-Br-CB(11)Br(11)(-) in high yield. The lithiation of 1-H-CB(11)X(11)(-) resembles that of its parent anion CB(11)H(12)(-). Treatment of these lithio species with methyl iodide gave the methylated carborane anions 1-CH(3)-CB(11)X(11)(-). These new weakly coordinating anions were fully characterized by (1)H, (13)C, and (11)B NMR, IR, and negative-ion MALDI MS spectroscopy. Some were further confirmed by single-crystal X-ray analysis.