Self-Assembling Sulfated Lactobacillus Exopolysaccharide Nanoparticles as Adjuvants for SARS-CoV-2 Subunit Vaccine Elicit Potent Humoral and Cellular Immune Responses.

Coronavirus disease 2019 (COVID-19) has caused a global pandemic since its onset in 2019, and the development of effective vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to induce potent and long-lasting immunity remains a priority. Herein, we prepared two Lactobacillus exopolysaccharide (EPS) nanoparticle adjuvants (NPs 7-4 and NPs 8-2) that were constructed by using sulfation-modified EPS and quaternization-modified chitosan. These two NPs displayed a spherical morphology with sizes of 39 and 47 nm. Furthermore, the zeta potentials of NPs 7-4 and NPs 8-2 were 50.40 and 44.40 mV, respectively. In vitro assays demonstrated that NPs could effectively adsorb antigenic proteins and exhibited a sustained release effect. Mouse immunization tests showed that the NPs induced the expression of cytokines and chemokines at the injection site and promoted the uptake of antigenic proteins by macrophages. Mechanically, the NPs upregulated the expression of pattern recognition receptors (toll-like receptors and nod-like receptors) and activated the immune response of T cells and the production of neutralizing antibodies. In addition, the NP adjuvants had favorable immune-enhancing effects in cats, which are of great significance for controlling the trans-host transmission and re-endemicity of SARS-CoV-2. Overall, we demonstrated that NP-adjuvanted SARS-CoV-2 receptor binding domain proteins could induce robust specific humoral and cellular immunity.

Effects of Continuous Nutritional Intervention on Nutritional Status and Serum Albumin During Maintenance Therapy in Children with Acute Lymphoblastic Leukemia.

Background: Nutritional imbalances can significantly impact clinical efficacy and chemotherapy tolerance in cases of acute lymphoblastic leukemia. Despite the potential significance, there is limited research in this domain, and clinicians have paid limited attention to it. Objective: This study aims to investigate the impact of continuous nutritional intervention on pediatric patients with acute lymphoblastic leukemia. Methods: A comparative analysis was conducted by dividing the children into observation and control groups, examining the effects of intermittent diet intervention and continuous nutrition intervention post-nutritional risk assessment. Results: After the intervention, the observation group exhibited a higher proportion of good nutrition and elevated serum albumin levels compared to the control group (χ2=4.79, 5.49, P = .029, 0.019, t =-2.819, -5.559, P = .01, P < .001). Additionally, the complication rate in the observation group was significantly lower than that in the control group (χ2=5.247, P = .022). Conclusions: Continuous nutrition intervention emerges as a valuable strategy for improving the nutritional status and serum albumin levels in children undergoing maintenance treatment for acute lymphoblastic leukemia. Moreover, it contributes to a noteworthy reduction in the incidence of complications.

[CaMKIIα-positive excitatory hippocampal neurons mediate "Zusanli" (ST36) electroacupuncture induced increase of gastric function in mice].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of "Zusanli"(ST36)on gastric function (food consumption and gastric emptying rate) and excitability of hippocampal glutamatergic neurons in mice, so as to explore its mechanism underlying enhancing gastrointestinal function. METHODS: The present study includes 2 parts. 1) C57BL/6 mice were randomly divided into normal and EA groups (n=12 in each group). EA (2 Hz/15 Hz, 1-3 mA) was applied to bilateral ST36 for 20 min, once daily for 7 days. In each group, 6 mice were used to measure the food consumption and gastric emptying rate, and the other 6 mice used to detect the hippocampal glutamate secretion content by using in vivo microdialysis and high performance liquid chromatography. 2) Thirty CaMKIIα-Cre mice received microinjection of a recombinant adeno-associated viral vector containing inhibitory designer receptor exclusively activated by a designer drug (DREADD, AAV-DIO-hM4Di-eYFP) into the hippocampus. Twenty-one days later, 3 mice were selected to observe the expression of eYFP-labeled hM4Di by immunohistochemistry, and 15 mice employed to observe the electrical activities of hM4Di-eYFP positive neurons exposed in chemogenetic activating drug Clozapine N-oxide (CNO) perfusion conditions (n=3) and without CNO in the recording chamber (n=6 in the control and EA groups) by using whole cell patch clamp. The rest 12 CaMKII-Cre mice were equally randomized into AAV-DIO-hM4Di-eYFP+CNO group and AAV-DIO-hM4Di-eYFP+CNO+EA group, and CNO was given by intraperitoneal injection for observing the effect of EA on gastric function. RESULTS: 1) In C57BL/6 mice, compared with the normal group, the food consumption, gastric emptying rate, and the glutamate content in the hippocampus were obviously increased in the EA group (P<0.01). 2) In CaMKIIα-Cre mice, the hM4Di-eYFP positive neurons distributing in the hippocampus showed an obvious increase of firing rates in the EA group relevant to the control group (P<0.01), and a hyperdepolarization potential after application of CNO. No significant changes were found between the AAV-DIO-hM4Di-eYFP+CNO and AAV-DIO-hM4Di-eYFP+CNO+EA groups in the food consumption and gastric emptying rate (P>0.05), suggesting an elimination of EA effect after acute DREADD-mediated activation of the CaMKIIα-positive hippocampal excitatory neurons. CONCLUSION: EA at ST36 can promote food intake and gastric emptying in normal mice but not in CaMKIIα-Cre mice with activated hippocampal hM4Di receptors，suggesting a contribution of the CaMKIIα-positive hippocampal excitatory neurons (glutamatergic neurons in particular) to the enhanced gastrointestinal function of EA at ST36.

Acupuncture at Gastric Back-Shu and Front-Mu Acupoints Enhances Gastric Motility via the Inhibition of the Glutamatergic System in the Hippocampus.

Acupuncture strongly alleviates gastrointestinal symptoms and especially promotes gastrointestinal motility. However, the mechanism underlying these processes is poorly understood. This study was designed to examine the effect of electroacupuncture (EA) at gastric back-shu (BL21) and front-mu (RN12) acupoints on gastric motility in functional dyspepsia (FD) rats and to investigate the mechanisms of its effects on the glutamatergic system in the hippocampus. We found that EA at RN12 or BL21 enhanced gastric motility in FD rats, whereas EA at the combination of RN12 and BL21 showed an additional effect. Microdialysis combined with HPLC showed that EA reduced the glutamate content in the hippocampus, and the NMDAR-NO-cGMP signalling pathway was downregulated, as determined by Western blot assays, in FD rats. In addition, we found that decreased gastric motility was significantly restored by the hippocampal infusion of an NMDAR, nNOS, or sGC antagonist. Interestingly, EA had no further effects on gastric motility in the presence of these antagonists in FD rats. Taken together, these results suggest that the hippocampal glutamatergic system is involved in the regulation of gastric motility by EA at RN12 and BL21.

Two new stilbenoids from aerial parts of Flickingeria fimbriata.

Two new stilbenoids, named 2,3 -dimethoxyl-7-hydroxyl-1,4-phenanthrenedione (1) and 2-methoxyl-3-methyl-7-hydroxyl-9,10-dihydro-1,4-phenanthrenedione (2), together with two known stilbenoids including densiflorol B (3) and ephemeranthoquinone (4), were isolated from aerial parts of Flickingeria fimbriata (Bl.) Hawkes. The structures of two new compounds were elucidated by extensive spectroscopic analysis, including HRESIMS, 1H and 13C NMR, DEPT, HMBC, COSY, HMQC, NOESY. All the compounds were obtained from this genus for the first time. In addition, they all exhibited moderate cytotoxic activities against HepG2 cell lines.

[A study on identification of edible bird's nests by DNA barcodes].

To provide theoretical basis for the traceability and quality evaluation of edible bird's nests (EBNs), the Cytb sequence was applied to identify the origin of EBNs. A total of 39 experiment samples were collected from Malaysia, Indonesia, Vietnam and Thailand. Genomic DNA was extracted for the PCR reaction. The amplified products were sequenced. 36 sequences were downloaded from Gen Bank including edible nest swiftlet, black nest swiftlet, mascarene swiftlet, pacific swiftlet and germain's swiftlet. MEGA 7.0 was used to analyze the distinction of sequences by the method of calculating the distances in intraspecific and interspecific divergences and constructing NJ and UPMGA phylogenetic tree based on Kimera-2-parameter model. The results showed that 39 samples were from three kinds of EBNs. Interspecific divergences were significantly greater than the intraspecific one. Samples could be successfully distinguished by NJ and UPMGA phylogenetic tree. In conclusion, Cytb sequence could be used to distinguish the origin of EBNs and it is efficient for tracing the origin species of EBNs.

Neural mechanism of gastric motility regulation by electroacupuncture at RN12 and BL21: A paraventricular hypothalamic nucleus-dorsal vagal complex-vagus nerve-gastric channel pathway.

AIM: To study the neural mechanism by which electroacupuncture (EA) at RN12 (Zhongwan) and BL21 (Weishu) regulates gastric motility. METHODS: One hundred and forty-four adult Sprague Dawley rats were studied in four separate experiments. Intragastric pressure was measured using custom-made rubber balloons, and extracellular neuron firing activity, which is sensitive to gastric distention in the dorsal vagal complex (DVC), was recorded by an electrophysiological technique. The expression levels of c-fos, motilin (MTL) and gastrin (GAS) in the paraventricular hypothalamic nucleus (PVN) were assayed by immunohistochemistry, and the expression levels of motilin receptor (MTL-R) and gastrin receptor (GAS-R) in both the PVN and the gastric antrum were assayed by western blotting. RESULTS: EA at RN12 + BL21 (gastric Shu and Mu points), BL21 (gastric Back-Shu point), RN12 (gastric Front-Mu point), resulted in increased neuron-activating frequency in the DVC (2.08 ± 0.050, 1.17 ± 0.023, 1.55 ± 0.079 vs 0.75 ± 0.046, P < 0.001) compared with a model group. The expression of c-fos (36.24 ± 1.67, 29.41 ± 2.55, 31.79 ± 3.00 vs 5.73 ± 2.18, P < 0.001), MTL (22.48 ± 2.66, 20.76 ± 2.41, 19.17 ± 1.71 vs 11.68 ± 2.52, P < 0.001), GAS (24.99 ± 2.95, 21.69 ± 3.24, 23.03 ± 3.09 vs 12.53 ± 2.15, P < 0.001), MTL-R (1.39 ± 0.05, 1.22 ± 0.05, 1.17 ± 0.12 vs 0.84 ± 0.06, P < 0.001), and GAS-R (1.07 ± 0.07, 0.91 ± 0.06, 0.78 ± 0.05 vs 0.45 ± 0.04, P < 0.001) increased in the PVN after EA compared with the model group. The expression of MTL-R (1.46 ± 0.14, 1.26 ± 0.11, 0.99 ± 0.07 vs 0.65 ± 0.03, P < 0.001), and GAS-R (1.63 ± 0.11, 1.26 ± 0.16, 1.13 ± 0.02 vs 0.80 ± 0.11, P < 0.001) increased in the gastric antrum after EA compared with the model group. Damaging the PVN resulted in reduced intragastric pressure (13.67 ± 3.72 vs 4.27 ± 1.48, P < 0.001). These data demonstrate that the signals induced by EA stimulation of acupoints RN12 and BL21 are detectable in the DVC and the PVN, and increase the levels of gastrointestinal hormones and their receptors in the PVN and gastric antrum to regulate gastric motility. CONCLUSION: EA at RN12 and BL21 regulates gastric motility, which may be achieved through the PVN-DVC-vagus-gastric neural pathway.