Arsenic is a semi-metal,and lipid-soluble arsenic compounds are one of the widespread forms in the environment and food chain,but there is a lack of standards for lipid-soluble arsenic compounds,which is one of the bottlenecks in the current analytical detection and toxicological studies of organic arsenic.In this study,four saturated arsenic-containing hydrocarbons,AsHC 318,AsHC 332,AsHC 346,and AsHC 374(The number is relative molecular mass),were successfully synthesized in three steps by using dimethylarsinic acid,potassium iodide,sodium hydroxide,and four brominated alkanes(1-Bromotetradecane,1-bromopentadecane,1-bromohexadecane,and 1-bromooctadecane)as raw materials.The structures of these four saturated arsenic-containing hydrocarbons were characterized by proton nuclear magnetic resonance(1H NMR)spectroscopy,13C nuclear magnetic resonance(13C NMR)spectroscopy,and high-resolution mass spectrometry(HR-MS).The yields of the method were 8%-10%,and the synthesized compounds could be used in subsequent toxicity evaluation experiments to assess the toxic effects and mechanisms of action of arsenic-containing hydrocarbons.This study provided an effective method for synthesis of arsenic-containing hydrocarbons,enriching the synthesis methods of arsenic-containing hydrocarbons,and provided raw materials for the subsequent toxicological studies of arsenic-containing hydrocarbons.

Objective: To grasp the epidemiological characteristics of influenza outbreaks in Guangdong Province by analyzing the outbreaks of influenza-like cases reported in Guangdong Province from January 2015 to the end of August 2022. Methods: In response to the outbreak of epidemics in Guangdong Province from 2015 to 2022, information on on-site epidemic control was collected, and epidemiological analysis was conducted to describe the characteristics of the epidemics. The factors that influence the intensity and duration of the outbreak were determined through a logistic regression model. Results: A total of 1 901 influenza outbreaks were reported in Guangdong Province, with an overall incidence of 2.05%. Most outbreak reports occurred from November to January of the following year (50.24%, 955/1 901) and from April to June (29.88%, 568/1 901). A total of 59.23% (1 126/1 901) of the outbreaks were reported in the Pearl River Delta region, and primary and secondary schools were the main places where outbreaks occurred (88.01%, 1 673/1 901). Outbreaks with 10-29 cases were the most common (66.18%, 1 258/1 901), and most outbreaks lasted less than seven days (50.93%,906/1 779). The size of the outbreak was related to the nursery school (aOR=0.38, 95%CI:0.15-0.93), the Pearl River Delta region (aOR=0.60, 95%CI:0.44-0.83), the time interval between the onset of the first case and the time of report (>7 days compared with ≤3 days: aOR=3.01, 95%CI:1.84-4.90), the influenza A(H1N1) (aOR=2.02, 95%CI:1.15-3.55) and the influenza B (Yamagata) (aOR=2.94, 95%CI: 1.50-5.76). The duration of outbreaks was related to school closures (aOR=0.65, 95%CI: 0.47-0.89), the Pearl River Delta region (aOR=0.65, 95%CI: 0.50-0.83) and the time interval between the onset of the first case and the time of report (>7 days compared with ≤3 days: aOR=13.33, 95%CI: 8.80-20.19; 4-7 days compared with ≤3 days: aOR=2.56, 95%CI: 1.81-3.61). Conclusions: An influenza outbreak in Guangdong Province exhibits two peaks, one in the winter and spring seasons and the other in the summer. Primary and secondary schools are high-risk areas, and early reporting of outbreaks is critical for controlling influenza outbreaks in schools. Furthermore, comprehensive measures should be taken to prevent the spread of the epidemic.
Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human/epidemiology* ; Disease Outbreaks ; Epidemics ; China/epidemiology*

Starting with the relationship between mulberry leaves and silkworm droppings as food and metabolites, this study systematically compared the chemical components, screened out differential components, and quantitatively analyzed the main differential components based on ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and UPLC-Q-TRAP-MS combined with principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA). Moreover, the in vitro enzymatic transformation of the representative differential components was studied. The results showed that(1) 95 components were identified from mulberry leaves and silkworm droppings, among which 27 components only exist in mulberry leaves and 8 components in silkworm droppings. The main differential components were flavonoid glycosides and chlorogenic acids.(2) Nineteen components with significant difference were quantitatively analyzed, and the components with significant differences and high content were neochlorogenic acid, chlorogenic acid, and rutin.(3) The crude protease in the mid-gut of silkworm significantly metabolized neochlorogenic acid and chlorogenic acid, which may be an important reason for the efficacy change in mulberry leaves and silkworm droppings. This study lays a scientific foundation for the development, utilization, and quality control of mulberry leaves and silkworm droppings. It provides references for clarifying the possible material basis and mechanism of the pungent-cool and dispersing nature of mulberry leaves transforming into the pungent-warm and dampness-resolving nature of silkworm droppings, and offers a new idea for the study of nature-effect transformation mechanism of traditional Chinese medicine.
Animals ; Bombyx ; Morus/chemistry* ; Chlorogenic Acid/analysis* ; Gas Chromatography-Mass Spectrometry ; Chromatography, High Pressure Liquid/methods* ; Plant Leaves/chemistry*

Humans ; Asthma/drug therapy* ; Biological Therapy

Lilii Bulbus is a commonly used Chinese herbal medicine with both medicinal and edible values, while the market products usually has the problem of sulfur fumigation. Therefore, the quality and safety of Lilii Bulbus products deserve attention. In this study, ultra-high performance liquid chromatography-time of flight-tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was combined with principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) to analyze the differential components of Lilii Bulbus before and after sulfur fumigation. We identified ten markers generated after sulfur fumigation, summarized their mass fragmentation and transformation patterns, and verified the structures of phenylacrylic acid markers of sulfur fumigation. At the same time, the cytotoxicity of the aqueous extracts of Lilii Bulbus before and after sulfur fumigation was evaluated. The results showed that in the concentration range of 0-800 mg·L~(-1), the aqueous extract of Lilii Bulbus after sulfur fumigation had no significant effect on the viability of human liver LO2 cells, human renal proximal tubular HK-2 cells, and rat adrenal pheochromocytoma PC-12 cells. Moreover, the viability of the cells exposed to the aqueous extract of Lilii Bulbus before and after sulfur fumigation showed no significant difference. This study identified phenylacrylic acid and furostanol saponins as markers of sulfur-fumigated Lilii Bulbus for the first time, and made clear that proper sulfur fumigation of Lilii Bulbus would not produce cytotoxicity, providing a theoretical basis for the rapid identification and quality and safety control of sulfur-fumigated Lilii Bulbus.
Humans ; Animals ; Rats ; Fumigation ; Tandem Mass Spectrometry ; Chromatography, High Pressure Liquid ; Epithelial Cells ; Sulfur

Aim To explore the effect of cuminaldehyde in cumin fruit on gastric ulcer and the protective mechanism via establishing the gastric ulcer model of rats was by ethanol injury. Methods Thirty-six male R. norregicus were divided into six groups: control group, model group, omeprazole positive control group and cuminaldehyde low, medium and high dosage groups. After seven days of continuous intragastric administration, the acute gastric ulcer of R. norregicus was tested by absolute alcohol. Gastric ulcer area, inhibition rate, gastric tissue antioxidant activity, serum inflammatory factors and gastric mucosal protective factors were detected in different groups. Results The results showed that cuminaldehyde significantly reduced the area of gastric ulcer and increased the inhibition rate of gastric ulcer. The inhibition rate of cuminaldehyde at high dose group was up to 74.65%, the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH) in gastric tissue significantly increased, and the contents of serum prolandin E

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.
COVID-19 ; Cohort Studies ; Contact Tracing ; Humans ; Incidence ; Prospective Studies

2019-nCoV Omicron (B.1.1.529) variant, which has brought new challenges to the prevention and control of COVID-19 pandemic, has the characteristics of stronger transmissibility and more rapid transmission and more significant immune evasion. It took only two months to become a predominant strain worldwide after its identification in South Africa in November 2021. Local epidemics caused by Omicron variant have been reported in several provinces in China. However, the epidemiological characteristics of highly mutated Omicron variant remain unclear. This article summarizes the progress in the research of functional mutations, transmissibility, virulence, immune evasion and cross-reactive immune responses of Omicron variant, to provide references for the effective prevention and control of COVID-19 pandemic caused by Omicron variant.
COVID-19 ; Humans ; Mutation ; Pandemics ; SARS-CoV-2

Objective: To analyze the epidemiological characteristics and influencing factors of COVID-19 confirmed cases with viral nucleic acid re-positive in anal and/or throat swabs after discharge during the domestic imported epidemic stage in Guangdong Province in early 2020. Methods: The COVID-19 confirmed cases with the onset time before March 1, 2020 in Guangdong Province were collected to analyze the demographic data, epidemiological characteristics, and specimen collection and testing data after discharge. Logistic regression model was used for influencing factors analysis of re-positive cases. Results: A total of 1 286 COVID-19 confirmed cases were included, the M(Q₁,Q₃) of age was 44(32,58)years, 617 cases were male, 224 cases were re-positive in anal and/or throat swabs with the re-positive rate 17.42%. The M(Q₁,Q₃) of age of re-positive cases was 35(23, 50) years, which was younger than that of re-negative cases age was those 46(33, 59) years (P<0.001). With the increase of age, re-positive rate decreased (χ²_trend=52.73, P<0.001). 85.27% (191/224) of re-positive cases were found in 14 d after discharge, the duration time of re-positive status was 13(7, 24) d, and 81.69% (183/224) of re-positive cases were re-tested negative in 28 d after re-positive date. No fever and other symptoms had been observed among re-positive cases during the whole follow-up. No secondary infectious cases had been found among close contacts after 14 d of centralized isolation and sampling screening. Univariate logistic regression model analysis revealed that the influencing factors of the re-positive cases included age, occupation, clusters, clinical types, and admission time. Multivariate logistic regression model analysis revealed that age was an independent risk factor. Conclusions: SARS-CoV-2 viral nucleic acid re-positive is found in COVID-19 confirmed cases after discharge in Guangdong Province. Most re-positive cases are confirmed among 14 d after discharge and re-test to negative among 28 d after re-positive date. Age is an risk factor for re-positive cases after discharge.
COVID-19 ; China/epidemiology* ; Epidemics ; Humans ; Male ; Nucleic Acids ; SARS-CoV-2

Abstract: Objective　To understand the distribution and drug resistance of common pathogens of fungal bloodstream infection in Sichuan, and to provide reference for clinicians to empirically treat fungal bloodstream infection. Methods　From November 1, 2019 to December 31, 2020, fungal strains isolated from blood culture of patients diagnosed with bloodstream infection in 19 tertiary first-class general hospitals in Sichuan Province were collected for mass spectrometry identification and drug susceptibility, and the results were statistically analyzed, along with a retrospective analysis of clinical data. Results　A total of 255 fungal strains were received and identified by mass spectrometry, 215 strains of Candida spp (84.3%), 28 strains of Cryptococcus neoformans (11.0%), 4 strains of Talaromyces marneffei (1.6%) and 8 strains of others (3.1%). Among the Candida spp 90 strains of Candida albicans, 39 strains of Candida parapsilosis complex, 36 strains of Candida glabrata, 33 strains of Candida tropicalis, 8 strains of Candida guilliermondii, and 9 strains of other Candida. In the department, the ICU was predominant, accounting for 35.7%. The top four Candida (Candida albicans, Candida parapsilosis complex, Candida glabrata, Candida tropicalis) were analyzed for drug sensitivity, Candida albicans and Candida parapsilosis complex group were more sensitive to antifungal drugs, the sensitivity rates of Candida albicans to fluconazole, voriconazole, anidulafungin, caspofungin, micarafungin were 89.2%, 92.8%, 97.6%, 97.6%, 96.4%, respectively. The sensitivity rates of Candida parapsilosis to fluconazole and voriconazole were 89.7% and 94.9%, and to anidulafungin, caspofungin and micafungin were all 100%. Echinocandins had stronger antibacterial activity against Candida spp., Candida parapsilosis complex and Candida tropicalis had 100% sensitivity to echinocandins, Candida albicans had more than 95% sensitivity to echinocandins, and Candida glabrata had about 90% sensitivity to echinocandins. Candida tropicalis was less sensitive to fluconazole and voriconazole with 66.7% and 54.5%, and the sensitivity of Candida glabrata to fluconazole was mainly concentrated in susceptible dose dependent (SDD), accounting for 91.4%. The four Candida species did not show resistance to amphotericin B, all of them showed wild-type strains, Candida tropicalis showed the highest non-wild-type rate to posaconazole and itraconazole with 21.2% and 36.4%, and the drug sensitivity results of Cryptococcus neoformans showed that 4 out of 23 strains showed resistance to amphotericin B (non-wild-type) and 3 strains showed resistance to fluconazole (non-wild-type). Conclusions　The fungus of bloodstream infection is mainly Candida spp.. Among of them, Candida albicans accounts for the highest percentage, echinocandins have good antibacterial effect on Candida, Candida is sensitive to amphotericin B as wild type, but Candida tropicalis has slightly higher resistance rate to fluconazole and voriconazole, and the non-wild type rate of Cryptococcus neoformans to amphotericin B is increasing, and clinicians should pay high attention to the rational use of antifungal drugs.