Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Infected Pneumonia.

BACKGROUND: The initial cases of novel coronavirus (2019-nCoV)-infected pneumonia (NCIP) occurred in Wuhan, Hubei Province, China, in December 2019 and January 2020. We analyzed data on the first 425 confirmed cases in Wuhan to determine the epidemiologic characteristics of NCIP. METHODS: We collected information on demographic characteristics, exposure history, and illness timelines of laboratory-confirmed cases of NCIP that had been reported by January 22, 2020. We described characteristics of the cases and estimated the key epidemiologic time-delay distributions. In the early period of exponential growth, we estimated the epidemic doubling time and the basic reproductive number. RESULTS: Among the first 425 patients with confirmed NCIP, the median age was 59 years and 56% were male. The majority of cases (55%) with onset before January 1, 2020, were linked to the Huanan Seafood Wholesale Market, as compared with 8.6% of the subsequent cases. The mean incubation period was 5.2 days (95% confidence interval [CI], 4.1 to 7.0), with the 95th percentile of the distribution at 12.5 days. In its early stages, the epidemic doubled in size every 7.4 days. With a mean serial interval of 7.5 days (95% CI, 5.3 to 19), the basic reproductive number was estimated to be 2.2 (95% CI, 1.4 to 3.9). CONCLUSIONS: On the basis of this information, there is evidence that human-to-human transmission has occurred among close contacts since the middle of December 2019. Considerable efforts to reduce transmission will be required to control outbreaks if similar dynamics apply elsewhere. Measures to prevent or reduce transmission should be implemented in populations at risk. (Funded by the Ministry of Science and Technology of China and others.).

Chlorogenic acid induces ROS-dependent apoptosis in Fusarium fujikuroi and decreases the postharvest rot of cherry tomato.

Chlorogenic acid is a plant polyphenol with antioxidant and antimicrobial activities. Fusarium fujikuroi is a fungal pathogen that causes many vegetables and fruits, including tomato, to rot. The effects of chlorogenic acid on the development of Fusarium rot of cherry tomato fruit were examined in the present study. Results showed that conidial germination, germ tube elongation, cell viability, and mycelial growth of F. fujikuroi were all significantly inhibited by chlorogenic acid. Chlorogenic acid stimulated the accumulation of reactive oxygen species (ROS), leading to cell apoptosis in F. fujikuroi. The addition of N-acetylcysteine partially recovered the mycelial growth, implying the antifungal activity of chlorogenic acid is related to a ROS burst. The application of chlorogenic acid decreased disease incidence and severity in cherry tomato fruit in a concentration-dependent manner. Taken together, these results suggest that chlorogenic acid inhibits the postharvest rot of cherry tomato fruit caused by F. fujikuroi by inducing cellular oxidative stress in the pathogen.

New Insights into Herb-Induced Liver Injury.

Significance: Herbs are widely used worldwide. However, inappropriate use of some of the herbs can lead to herb-induced liver injury (HILI). Intriguingly, HILI incidents are on the rise, and our understanding of the underlying etiologies is in progress, and hence, an update on the current status of incidents as well as our understanding on the etiologies of HILI is appropriate. Recent Advances: HILI reports due to the use of some herbs that are traditionally considered to be safe are also on the rise. Furthermore, HILI due to the use of certain herbs in combination with other herbs (herb-herb interaction [HHI]) or non-herb components (herb-drug interaction [HDI]) has also been reported, suggesting a potentially important new type of inappropriate use of herbs. Critical Issues: Updated overviews focus on the epidemiology, etiology, phenotypes, and risk factors of HILI, as well as HDI and HHI, and analysis on several types of newly reported "toxic" effects of herbs based on types of hepatotoxicity and the HILI mechanisms. Future Directions: HILI will continue to be a significant public health challenge in the near future. In the light of the lack of broadly available guidelines and regulations for proper and safe uses of herbs worldwide, raising the public awareness of HILI will remain one of the most effective measures. In particular, it should include a better understanding of the contributing factors; a more detail subclassification and description of HILI, better characterization of the components/substances that could induce HILI; and development of HILI diagnosis based on the Roussel Uclaf Causality Assessment Method (RUCAM). Antioxid. Redox Signal. 38, 1138-1149.

Curcumin inhibits Aspergillus flavus infection and aflatoxin production possibly by inducing ROS burst.

Aspergillus flavus contamination is common in various food and feed ingredients, and it poses to serious threats to human and animal health. Curcumin is a plant-derived polyphenol that exhibits antifungal activity. In this study, the antifungal effect of curcumin on A. flavus was evaluated, and the underlying mechanism was investigated. Curcumin effectively decreased aflatoxin B1 synthesis and suppressed A. flavus infection in peanut. Curcumin inhibited the mycelial growth and sporulation of A. flavus. Ergosterol biosynthesis in A. flavus was suppressed, and cell membrane permeability was enhanced. The pathogenicity of A. flavus was also reduced by curcumin treatment. Curcumin induced ROS burst in the hyphae of A. flavus, and those damages could be reversed by exogenous superoxide dismutase, suggesting that curcumin inhibited A. flavus possibly via inducing oxidative stress. These results indicate that curcumin has the potential to be used as a preservative to control A. flavus contamination in food and feedstuff.

A clinical experience-based Chinese herbal formula improves ethanol-induced drunken behavior and hepatic steatohepatitis in mice models.

BACKGROUND: Bao-Gan-Xing-Jiu-Wan (BGXJW) is a clinical experience-based Chinese herbal formula. Its efficacy, pharmacological safety, targeted function, process quality, and other aspects have met the evaluation standards and the latest requirements of preparations. It could prevent and alleviate the symptoms of drunkenness and alcoholic liver injury clinically. The present work aims to elucidate whether BGXJW could protect against drunkenness and alcoholic liver disease in mice and explore the associated mechanism. MATERIAL AND METHODS: We used acute-on-chronic (NIAAA) mice model to induce alcoholic steatosis, and alcohol binge-drinking model to reappear the drunk condition. BGXJW at indicated doses were administered by oral gavage respectively to analyze its effects on alcoholic liver injury and the associated molecular mechanisms. RESULTS: BGXJW had no cardiac, hepatic, renal, or intestinal toxicity in mice. Alcoholic liver injury and steatosis in the NIAAA mode were effectively prevented by BGXJW treatment. BGXJW increased the expression of alcohol metabolizing enzymes ADH, CYP2E1, and ALDH2 to enhance alcohol metabolism, inhibited steatosis through regulating lipid metabolism, counteracted alcohol-induced upregulation of lipid synthesis related proteins SREBP1, FASN, and SCD1, meanwhile it enhanced fatty acids ß-oxidation related proteins PPAR-α and CPT1A. Alcohol taken enhanced pro-inflammatory TNF-α, IL-6 and down-regulated the anti-inflammatory IL-10 expression in the liver, which were also reversed by BGXJW administration. Moreover, BGXJW significantly decreased the blood ethanol concentration and alleviated drunkenness in the alcohol binge-drinking mice model. CONCLUSIONS: BGXJW could effectively relieve drunkenness and prevent alcoholic liver disease by regulating lipid metabolism, inflammatory response, and alcohol metabolism.

Metabolomic Profiling for Histologically Fibrotic Stage in Chronic Drug-Induced Liver Injury.

Background and aims: Chronic drug-induced liver injury (DILI) is a rare but under-researched adverse drug reaction-related disease, which is highly likely to progress into liver fibrosis and even cirrhosis. In this study, metabolomics was used to screen out characteristic metabolites related to the histological progression of fibrosis in chronic DILI and analyze the metabolic changes during the development of fibrosis to explain the underlying mechanism. Methods: Chronic DILI patients who underwent liver biopsy were divided into different fibrosis grades. Serum was analyzed by untargeted metabolomics to find serological characteristic metabolite fingerprints. The screened fingerprints were validated by the validation group patients, and the identification ability of fingerprints was compared using FibroScan. Results: A total of 31 metabolites associated with fibrosis and 11 metabolites associated with advanced fibrosis were identified. The validation group confirmed the accuracy of the two metabolite fingerprints [area under the curve (AUC) value 0.753 and 0.944]. In addition, the fingerprints showed the ability to distinguish the grades of fibrosis by comparing using FibroScan. The metabolite fingerprint pathway showed that bile acid synthesis is disturbed while lipid metabolism is extremely active, resulting in an overload of lipid metabolites in the occurrence and development of chronic DILI-associated fibrosis. Conclusions: Our metabolomic analysis reveals the unique metabolomic fingerprints associated with chronic DILI fibrosis, which have potential clinical diagnostic and prognostic significances. The metabolomic fingerprints suggest the disturbance of the lipid metabolites as the most important factor in the development of DILI fibrosis.

Metabolomic Analysis Uncovers Lipid and Amino Acid Metabolism Disturbance During the Development of Ascites in Alcoholic Liver Disease.

Ascites is one of the most common complications of cirrhosis, and there is a dearth of knowledge about ascites-related pathologic metabolism. In this study, 122 alcoholic liver disease (ALD) patients, including 49 cases without ascites, 18 cases with mild-ascites, and 55 cases with large-ascites (1) were established according to the International Ascites Club (2), and untargeted metabolomics coupled with pattern recognition approaches were performed to profile and extract metabolite signatures. A total of 553 metabolites were uniquely discovered in patients with ascites, of which 136 metabolites had been annotated in the human metabolome database. Principal component analysis (PCA) analysis was used to further identify 21 ascites-related fingerprints. The eigenmetabolite calculated by reducing the dimensions of the 21 metabolites could be used to effectively identify those ALD patients with or without ascites. The eigenmetabolite showed a decreasing trend during ascites production and accumulation and was negatively related to the disease progress. These metabolic fingerprints mainly belong to the metabolites in lipid metabolism and the amino acid pathway. The results imply that lipid and amino acid metabolism disturbance may play a critical role in the development of ascites in ALD patients and could be a potent prognosis marker.

Metabolomic profiling for drug-induced liver injury with autoantibodies.

BACKGROUNDS: Drug induced liver injury (DILI) is sometimes similar to autoimmune hepatitis (AIH) in serology and histology. Clinicians empirically screened DILI with significant autoimmune characteristics to implement clinical intervention. We tried to characterize DILI with autoantibodies by metabolomics. METHODS: Untargeted metabolomics coupled with pattern recognition approaches were performed on sera samples including AIH (n = 59), DILI with autoantibodies (DILIAb+, n = 68), and DILI without autoantibodies (DILIAb-, n = 75). The differential metabolites and fingerprint metabolites between AIH and DILIAb- were screened by orthogonal partial least squares-discriminant analysis and hierarchical clustering respectively. RESULTS: Of the 388 annotated differential metabolites between AIH and DILIAb-, 74 fingerprint metabolites were screened. The eigenmetabolite compressed from the fingerprint possessed high discrimination efficacy (AUC:0.891; 95 %CI, 0.838-0.944). In the fingerprint-based PCA model, AIH and DILIAb- were separated into three regions: the "pure region" of AIH (Region 1), the "pure region" of DILIAb- (Region 3), the mixture region of AIH and DILIAb- (Region 2). After incorporated into the PCA model, DILIAb+ samples were distributed into the three regions, indicating that DILIAb+ samples had different etiological tendencies. Moreover, the fingerprint-based radar model verified the results of PCA model characterizing DILIAb+. Notably, the antibody titers of DILIAb+ in the three regions did not differ significantly, while the response rates for glucocorticoids were obviously different. The metabolic difference among DILIAb+ in different regions mainly lies in energy metabolism. CONCLUSIONS: In terms of metabolic signature, DILIAb+ may not be a community of same pathogenesis, including AIH-inclined parts. Which deserves further study.

Correction: Porcine Reproductive and Respiratory Syndrome Virus Nonstructural Protein 4 Induces Apoptosis Dependent on Its 3C-Like Serine Protease Activity.

[This corrects the article DOI: 10.1371/journal.pone.0069387.].

Unique Responses of Hepatocellular Carcinoma and Cholangiocarcinoma Cell Lines toward Cantharidin and Norcantharidin.

The present study aimed to investigate whether cell lines from human gastric and liver cancers respond differently toward cantharidin (CTD) and norcantharidin (NCTD) than other types of cancer cells. We first established the half maximal inhibitory concentrations (IC50s) of CTD for a large panel of cancer cell lines representing the 12 major types of human cancers and the mode of cell death induced by the two compounds. We next compared the growth inhibitory effects as well as the corresponding modes of action of CTD and NCTD. The IncuCyte ZOOM system was used as a semi-high throughput means to define IC50s and 90% inhibitory doses (IC90s) as a reference for the maximal tolerable doses (MTDs) for the two compounds in 72 cancer cell lines. Classical clonogenic survival assay was used to assess the anti-proliferative effect of CTD on selected cell lines of interest. In addition, DNA content-based flow was used to interrogate the modes of cell death following CTD or NCTD exposure. The results of these experiments led to several findings. 1). Cell lines representing hepatocellular carcinomas (HCCs) and cholangiocarcinomas (CCs) were among the most sensitive toward CTD, consistent with the previous clinical study of this compound and its source of origin, Mylabris. 2). Among the individual cell lines of a given cancer types, the sensitivity trends for CTD and NCTD did not exhibit a good correlation. 3) CTD and NCTD caused distinctive cytotoxic effects on HepG2 cells. Specifically, while a cytostatic effect is the primary cause of growth inhibition of CTD, cytotoxic effect is the main contributing factor for the growth inhibition of NTCD. These results indicate that liver cancer cell lines are among the most sensitive to CTD and that CTD and NCTD exhibit their effects through distinct mechanisms.

A new bioluminescent imaging technology for studying oxidative stress in the testis and its impacts on fertility.

PURPOSE: Excessive oxidative stress (OS) leads to cellular dysfunctions and cell death and constitutes a major cause of male infertility. However, the etiologies of increased reactive oxygen species (ROS) in male infertility is not fully understood. One major limitation is the lack of an in vivo imaging system that can be used to effectively study the impact of excessive ROS in the testis. Recently, we discovered that the hepatocellular carcinoma reporter (HCR) mice previously generated in our laboratory also expressed luciferase in the spermatids of the testis. The goal of the current study is to use the HCR mice to detect OS in the testis and to investigate the potential use of this new system in studying OS-induced male infertility. EXPERIMENTAL DESIGN: Bioluminescence imaging (BLI) was performed in HCR mice that were treated with peroxy caged luciferin-1 (PCL-1), an OS reporter, to establish a new mouse model for in vivo monitoring of the OS status inside the male reproductive tract. Subsequently, the effect of acetaminophen (APAP) overdose on the OS inside the testis and male fertility were determined. Lastly, APAP was co-administered with glutathione, an antioxidant reagent, to test if the HCR mice can serve as a model for the effective and rapid assessment of the potency of individual agents in modifying the OS inside the mouse testis. RESULTS: The OS level in the testis in the HCR mice was readily detected by BLI. The use of this new model led to the discovery that APAP caused a sudden rise of OS in the testis and was a potent toxicant for the male reproductive system. Moreover, administration of glutathione was effective in preventing the APAP-induced elevation of OS and in ameliorating all of the OS-induced anomalies in the testis. CONCLUSIONS: The HCR mice represent an excellent model for monitoring OS change in the mouse testis by real time BLI. APAP is a potent male reproductive toxicant and APAP-treated mice represent a valid model for OS-induced male infertility. This model can be used to study OS-induced damage in male reproductive tract and in assessing the effects of therapeutic agents on the relative levels of OS and male fertility.

Effect of noninvasive focused ultrasound stimulation on gamma oscillations in rat hippocampus.

In recent years, noninvasive focused ultrasound stimulation (FUS), with the advantage of high spatial resolution and high penetration depth, has developed rapidly for modulating neuron activities in the brain. Gamma oscillations serve to synchronize neurons and play important roles in cortical information processing and cognitive function. However, how FUS modulates gamma oscillations in the rat hippocampus is not well understood. In this work, we characterized the interactions between the gamma amplitude and phases of the delta, theta, and alpha bands during FUS. Our results show that FUS can significantly modulate the extent of phase-locked gamma amplitude and phase-amplitude coupling of brain oscillations. In summary, FUS can modulate gamma oscillations in the rat hippocampus, indicating its potential as a powerful noninvasive method to interfere with brain rhythms for diagnostic and therapeutic purposes.

Noninvasive Focused Ultrasound Stimulation Can Modulate Phase-Amplitude Coupling between Neuronal Oscillations in the Rat Hippocampus.

Noninvasive focused ultrasound stimulation (FUS) can be used to modulate neural activity with high spatial resolution. Phase-amplitude coupling (PAC) between neuronal oscillations is tightly associated with cognitive processes, including learning, attention, and memory. In this study, we investigated the effect of FUS on PAC between neuronal oscillations and established the relationship between the PAC index and ultrasonic intensity. The rat hippocampus was stimulated using focused ultrasound at different spatial-average pulse-average ultrasonic intensities (3.9, 9.6, and 19.2 W/cm(2)). The local field potentials (LFPs) in the rat hippocampus were recorded before and after FUS. Then, we analyzed PAC between neuronal oscillations using a PAC calculation algorithm. Our results showed that FUS significantly modulated PAC between the theta (4-8 Hz) and gamma (30-80 Hz) bands and between the alpha (9-13 Hz) and ripple (81-200 Hz) bands in the rat hippocampus, and PAC increased with incremental increases in ultrasonic intensity.

Recombinant Kluyveromyces lactis expressing highly pathogenic porcine reproductive and respiratory syndrome virus GP5 elicits mucosal and cell-mediated immune responses in mice.

Currently, killed-virus and modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccines are used to control porcine reproductive and respiratory syndrome. However, both types of vaccines have inherent drawbacks; accordingly, the development of novel PRRSV vaccines is urgently needed. Previous studies have suggested that yeast possesses adjuvant activities, and it has been used as an expression vehicle to elicit immune responses to foreign antigens. In this report, recombinant Kluyveromyces lactis expressing GP5 of HP-PRRSV (Yeast-GP5) was generated and immune responses to this construct were analyzed in mice. Intestinal mucosal PRRSV-specific sIgA antibody and higher levels of IFN-γ in spleen CD4(+) and CD8(+) T cells were induced by oral administration of Yeast-GP5. Additionally, Yeast-GP5 administered subcutaneously evoked vigorous cell-mediated immunity, and PRRSV-specific lymphocyte proliferation and IFN-γ secretion were detected in the splenocytes of mice. These results suggest that Yeast-GP5 has the potential for use as a vaccine for PRRSV in the future.

CTLA4 mediated targeting enhances immunogenicity against PRRSV in a DNA prime/killed virus boost strategy.

Porcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent of porcine reproductive and respiratory syndrome (PRRS), causing heavy economic losses to the swine industry all over the world. As current vaccination strategies could only confer limited and incomplete protection against PRRSV infection, a safe and efficient PRRSV vaccine is urgently needed. Vaccination with cytotoxic-T-lymphocyte-associated protein 4 (CTLA4) and antigen fusion expression plasmid which could target antigens to antigen presenting cells (APCs) has shown promising improvement of immunogenicity to antigens. In the present study, a fusion expression plasmid of CTLA4 and PRRSV GP5 was constructed. PRRSV-specific antibodies, neutralizing antibodies (NAs), cytokines of IFNγ and IL4, and the lymphocyte proliferation activity were analyzed in mice immunized with the constructed plasmids. Immunization of mice with the CTLA4 targeted plasmid leads to a significant enhancement of humoral and cellular immune responses. Moreover, this effect could be further augmented when the mice were boosted with a killed PRRSV vaccine after DNA vaccine priming. Our data imply that both the APC-target and heterologous prime-boost strategies could be used to improve the immune efficacy of vaccines against PRRSV in pigs in the future.

Porcine reproductive and respiratory syndrome virus nonstructural protein 4 induces apoptosis dependent on its 3C-like serine protease activity.

Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease in pigs caused by PRRS virus (PRRSV). Although PRRSV infection-induced cell apoptosis has been established, the related viral protein is still unknown. Here, we reported that PRRSV nonstructural protein 4 (nsp4) was a critical apoptosis inducer. Nsp4 could activate caspase-3, -8, and -9. Using truncated constructs without different domains in nsp4, we demonstrated that the full-length of nsp4 structure was required for its apoptosis-inducing activity. Furthermore, using site-directed mutagenesis to inactivate the 3C-like serine protease activity of nsp4, we showed that nsp4-induced apoptosis was dependent on its serine protease activity. The ability of nsp4 to induce apoptosis was significantly impaired by His39, Asp64, and Ser118 mutations, suggesting that His39, Asp64, and Ser118 were essential for nsp4 to trigger apoptosis. In conclusion, our present work showed that PRRSV nsp4 could induce apoptosis in host cells and might be partially responsible for the apoptosis induced by PRRSV infection. PRRSV 3C-like protease-mediated apoptosis represents the first report in the genus Arterivirus, family Arteriviridae.