Biosynthesis of Bt-Ag2O nanoparticles using Bacillus thuringiensis and their pesticidal and antimicrobial activities.

Nanosilver oxide exhibits strong antibacterial and photocatalytic properties and has shown great application potential in food packaging, biochemical fields, and other fields involving diseases and pest control. In this study, Ag2O nanoparticles were synthesized using Bacillus thuringiensis (Bt-Ag2O NPs). The physicochemical characteristics of the Bt-Ag2O NPs were analyzed by UV‒vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), inductively coupled plasma emission spectrometry (ICP), high-resolution transmission electron microscopy (HR-TEM), and zeta potential. The phis-chemical characterization revealed that the Bt-Ag2O NPs are in spherical shape with the small particle size (18.24 nm), high crystallinity, well dispersity, and stability. The biopesticidal and antifungal effects of Bt-Ag2O NPs were tested against Tribolium castaneum, Aspergillus flavus, and Penicillium chrysogenum. The survival, growth, and reproduction of tested pests and molds were significantly inhibited by Bt-Ag2O NPs in a dose-dependent manner. Bt-Ag2O NPs showed higher pesticidal activities against T. castaneum than Bt and commercial Ag2O NPs. The LC50 values of Bt, Ag2O NPs, and Bt-Ag2O NPs were 0.139%, 0.072%, and 0.06% on day 14, respectively. The Bt-Ag2O NPs also showed well antifungal activities against A. flavus and P. chrysogenum, while it resulted a small inhibition zone than commercial Ag2O NPs did. In addition, A. flavus showed much more sensitive to Bt-Ag2O NP treatments, compared to P. chrysogenum. Our results revealed that Bt-Ag2O NPs synthesized using B. thuringiensis could act as pesticides and antifungal agents in stored-product fields. KEY POINTS: • Bt-Ag2O NPs could be synthesized using Bacillus thuringiensis (Bt). • The NPs showed a high degree of crystallinity, spherical shape, and small particle size. • The NPs also showed excellent insecticidal and antifungal activity.

Microencapsulation of Capsaicin in Chitosan Microcapsules: Characterization, Release Behavior, and Pesticidal Properties against Tribolium castaneum (Herbst).

Capsaicin is a capsaicinoid in hot chili peppers, with excellent antibacterial and antimicrobial activities and a good safety profile, but its poor solubility and instability restrict its effectiveness. This limitation may be mitigated by encapsulation. Herein, capsaicin microcapsules (CCMs) were prepared through layer-by-layer self-assembly, using chitosan and carboxymethyl chitosan as shell materials. The chemical and microstructure structural characterization was evaluated by the methods of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The SEM indicated the microcapsules were irregular in shape with an average size of about 100 µm. The encapsulation had a high loading efficiency of 64.31%. FTIR and XRD revealed the absence of the interaction between the core and shell materials and the amorphous nature of the CCMs. The analysis results of the microcapsules' release behavior showed the burst release of capsaicin in 7 days and a slow progression afterward in three solutions, with the highest release properties in a basic solution, followed by acidic and neutral salt solutions. The entomotoxicity of CCMs was conducted against Tribolium castaneum (Herbst), and its efficacy was compared with pure capsaicin. The CCMs were found to be highly effective against this pest. The LC50 value for capsaicin and its microcapsules was 31.37 and 29.75 mg/kg on adults, respectively. According to these values, T. castaneum's development and reproduction were significantly inhibited compared with the control group. The excellent physicochemical characteristics and insecticidal performance show a high application value for integrated pest control.

Acupuncture for chronic constipation in patients with diabetes mellitus: A protocol for systematic review.

BACKGROUND: Assessing the effectiveness and safety of acupuncture for chronic constipation in patients with diabetes mellitus is the main purpose of this systematic review protocol. METHODS: The following electronic databases will be searched from their respective inception dates to December 1st 2020: PubMed, the Cochrane Library, Embase, World Science Net, the Allied and Complementary Medicine Database, the Web of Science, China National Knowledge Infrastructure, the Chongqing VIP Chinese Science and Technology Periodical Database and the Wanfang Database. All published randomized controlled trials in English or Chinese related to acupuncture for constipation in patient with diabetes mellitus will be included. The Bristol stool scale, spontaneous complete bowel movements, and observing symptoms (yes/no) including defecation feeling, defecation weakness, feeling of incomplete evacuation, bloating, and flatulence were considered as primary measures. The treatment efficiency consideration according to Bristol stool scale was considered as secondary measure. Two reviewers will conduct the study selection, data extraction and assessment independently. The assessment of risk of bias and data synthesis will be conducted with Review Manager Software (RevMan) V.5.2. RESULTS: The results will provide a high-quality synthesis of current evidence for researchers in this subject area. CONCLUSION: The conclusion of our study will provide an evidence to judge whether.Acupuncture is an effective intervention for chronic constipation in patients with diabetes mellitus. ETHICS AND DISSEMINATION: Formal ethical approval is not necessary as the data cannot be individualized. The results of this protocol will be disseminated in a peer-reviewed journal or presented at relevant conferences. PROSPERO REGISTRATION NUMBER: INPLASY202110079.

Inhibition of mitochondrial respiration under hypoxia and increased antioxidant activity after reoxygenation of Tribolium castaneum.

Regulating the air in low-oxygen environments protects hermetically stored grains from storage pests damage. However, pests that can tolerate hypoxic stress pose a huge challenge in terms of grain storage. We used various biological approaches to determine the fundamental mechanisms of Tribolium castaneum to cope with hypoxia. Our results indicated that limiting the available oxygen to T. castaneum increased glycolysis and inhibited the Krebs cycle, and that accumulated pyruvic acid was preferentially converted to lactic acid via anaerobic metabolism. Mitochondrial aerobic respiration was markedly suppressed for beetles under hypoxia, which also might have led to mitochondrial autophagy. The enzymatic activity of citrate synthase decreased in insects under hypoxia but recovered within 12 h, which suggested that the beetles recovered from the hypoxia. Moreover, hypoxia-reperfusion resulted in severe oxidative damage to insects, and antioxidant levels increased to defend against the high level of reactive oxygen species. In conclusion, our findings show that mitochondria were the main target in T. castaneum in response to low oxygen. The beetles under hypoxia inhibited mitochondrial respiration and increased antioxidant activity after reoxygenation. Our research advances the field of pest control and makes it possible to develop more efficient strategies for hermetic storage.

Comparative metabolomics analysis of Callosobruchus chinensis larvae under hypoxia, hypoxia/hypercapnia and normoxia.

BACKGROUND: Insect tolerance to low oxygen (hypoxia) and high carbon dioxide (hypercapnia) is critical for insect control. On the basis of bioassay, metabolism profiles were built to investigate adaptive mechanisms in bean weevil under hypoxia (2% O2 ), hypoxia/hypercapnia (2% O2 + 18% CO2 ) and normoxia (control, 20% O2 + 80% N2 ) using gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS). RESULTS: The growth and development of bean weevils were significantly suppressed by the two hypoxia conditions; hypercapnia enhanced the mortality, but after 24 days of exposure, the surviving insects emerged as adults earlier than those under hypoxia only. Metabolism profiles also showed striking differences in metabolites among the treatment and control groups, both quantitatively and qualitatively. Pairwise comparisons of the three groups showed that 61 metabolites changed significantly, 40 in the hypoxia group and 37 in the hypoxia/hypercapnia group relative to the control group, while only 16 were shared equally by the hypoxia and hypoxia/hypercapnia groups. Increased metabolites were mainly carbohydrates, amino acids and organic acids, while free fatty acids were decreased. Furthermore, the changes were strengthened by the addition of hypercapnia, but excluding free fatty acids. CONCLUSION: The findings show that bean weevil has high tolerance to hypoxia or even hypoxia/hypercapnia at biologically achievable levels and provide more direct evidence for stored product insect mechanism regulation under hypoxia stress, especially free fatty acid regulation by hypercapnia but not by hypoxia. © 2016 Society of Chemical Industry.

[Detection and analysis of HAV-HEV, HGV infection in patients with viral hepatitis].

OBJECTIVE: To study the simple infection and super/co-infection of HAV-HEV, HGV in patients with viral hepatitis. METHODS: Using EIA method to detect anti-HAV IgM, HBV serum markers, anti-HCV IgM, anti-HDV IgM, anti-HEV IgM, anti-HGV IgM in viral hepatitis patients with different clinical types. RESULTS: Seventy-three percent patients (154/210) had HBV infection markers, twenty-nine percent patients (61/210) had HAV infection marker, eight percent patients (17/210) had HCV, HDV infection markers, ten percent patients (21/210) had HEV infection and seven percent patients (15/210) had HGV infection. Only nine percent patients (20/210) had viral hepatitis serum markers negative. In all clinical types, sixty-one percent patients had only one type hepatitis virus infection, thirty-two percent patients had two types of hepatitis virus super/co-infection, six percent patients had three types of hepatitis virus super/co-infection. Super/co-infection often occurred in patients who had cirrhosis or hepatic failure. CONCLUSION: HBV and HAV infection is very common in viral hepatitis patients, whereas HCV, HDV, HEV and HGV infection is relatively low; double super/co-infection of HAV-HEV, HGV frequently occurs in severe patients with viral hepatitis.

[Relationship between hepatitis G virus infection and hepatic failure].

OBJECTIVE: To study the pathogenic effect of hepatitis G virus (HGV) infection on hepatic failure. METHODS: Using the RT-PCR and EIA techniques to detect HGV RNA and anti-HGV in sera of hepatic failure patients and compare them with their liver function and mortality rates. RESULTS: There was no significant difference about the positive rates of HGV among acute hepatic failure, subacute hepatic failure and chronic hepatic failure groups (X(2)=2.54, P>0.05). The level of ALT in HGV-positive group was slightly lower than that in HGV-negative group. The concentration of bilirubin and globulin was higher in HGV-positive group than HGV-negative group, and the concentration of albumin in HGV-positive group was significantly lower than that in HGV-negative group (t=2.59, P<0.05). The mortality rate in HGV-positive group was significantly lower than that in HGV-negative group (X(2)=4.68, 0.01