Dengue overview: An updated systemic review

Dengue is caused by the dengue virus (DENVs) infection and clinical manifestations include dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). Due to a lack of antiviral drugs and effective vaccines, several therapeutic and control strategies have been proposed. A systemic literature review was conducted according to PRISMA guidelines to select proper references to give an overview of DENV infection. Results indicate that understanding the virus characteristics and epidemiology are essential to gain the basic and clinical knowledge as well as dengue disseminated pattern and status. Different factors and mechanisms are thought to be involved in the presentation of DHF and DSS, including antibody-dependent enhancement, immune dysregulation, viral virulence, host genetic susceptibility, and preexisting dengue antibodies. This study suggests that dissecting pathogenesis and risk factors as well as developing different types of therapeutic and control strategies against DENV infection are urgently needed.

Understanding the role of galectins toward influenza A virus infection

INTRODUCTION

Influenza A virus (IAV) is highly contagious and causes respiratory diseases in birds, mammals, and humans. Some strains of IAV, whether from human or avian sources, have developed resistance to existing antiviral drugs. Therefore, the discovery of new influenza antiviral drugs and therapeutic approaches is crucial. Recent studies have shown that galectins (Gal), a group of β-galactose-binding lectins, play a role in regulating various viral infections, including IAVs.

AREAS COVERED

This review provides an overview of the roles of different galectins in IAV infection. We discuss the characteristics of galectins, their impact on IAV infection and spread, and highlight their positive or negative regulatory functions and potential mechanisms during IAV infection. Furthermore, we explore the potential application of galectins in IAV therapy.

EXPERT OPINION

Galectins were first identified in the mid-1970s, and currently, 15 mammalian galectins have been identified. While all galectin members possess the carbohydrate recognition domain (CRD) that interacts with β-galactoside, their regulatory functions vary in different DNA or RNA virus infections. Certain galectin members have been found to regulate IAV infection through diverse mechanisms. Therefore, a comprehensive understanding of their roles in IAV infection is essential, as it may pave the way for novel therapeutic strategies.

DC-SIGN and Galectin-3 individually and collaboratively regulate H5N1 and H7N9 avian influenza a virus infection via interaction with viral envelope hemagglutinin protein

DC-SIGN and Galectin-3 are two different lectins and have been reported to participate in regulation of several virus infections. WHO has pointed that H5N1 and H7N9 avian influenza viruses (AIVs) play continuous threats to global health. AIV hemagglutinin (HA) protein, a highly glycosylated protein, mediated influenza infection and was proposed to have DC-SIGN and Gal3 interactive domains. This study aims to address the individual and collaborative roles of DC-SIGN and Gal3 toward AIVs infection. Firstly, A549 cells with DC-SIGN expression or Gal3-knockdown, via lentiviral vector-mediated CD209 gene expression or LGALS-3 gene knockdown, respectively were generated. Quantitative Reverse Transcription PCR (qRT-PCR) results indicated that DC-SIGN expression and Gal3 knockdown in A549 cells were significantly promoted and ameliorated HA or NP gene expression, respectively after H5N1 and H7N9-reverse genetics (RG) virus post-infections (P < 0.05). Similar results observed in immunoblotting, indicating that DC-SIGN expression significantly facilitated H5N1-RG and H7N9-RG infections (P < 0.05) whereas Gal3 knockdown significantly reduced both viral infections (P < 0.05). Furthermore, we found that DC-SIGN and Gal3 co-expression significantly enhanced infectivity of both H5N1-RG and H7N9-RG viruses (P < 0.01) and higher regulatory capabilities by DC-SIGN and Gal3 in H5N1-RG than H7N9-RG was noted. The promoting effect mainly relied on exogenous Gal3 and DC-SIGN directly interacting with the HA protein of H5N1 or H7N9 AIVs, subsequently enhancing virus infection. This study sheds light on two different lectins individually and collaboratively regulating H5N1 and H7N9 AIVs infection and the inhibitors against DC-SIGN and Gal3 interacting with HA could be utilized as alternative antiviral strategies.

[Effects of bariatric surgery on sex hormones in male patients with obesity]

Objective: To analyze and evaluate the differences in sex hormones after laparoscopic Roux-en-Y Gastric Bypass Surgery (LRYGB) and laparoscopic sleeve gastrectomy (LSG) in male patients with obesity. Methods: This study was a retrospective cohort study. The inclusion criteria were (1) male patients with obesity who met the surgical indications of the "Chinese Guidelines for Surgical Treatment of Obesity and Type 2 Diabetes" (2019 Edition); (2) patients with a body mass index (BMI) of ≥27.5 kg/m2 and obesity-related metabolic diseases, or patients with severe obesity and a BMI of ≥35 kg/m2; and (3) sex hormone levels checked 1 year after surgery. The exclusion criteria included (1) patients with endocrine diseases (thyrotoxicosis, hyperprolactinemia) and hypothalamic-pituitary lesions and (2) those with severe major organ dysfunction who could not tolerate anesthesia or surgery. According to the above criteria, the clinical data of male patients with obesity admitted to the Gastrointestinal Surgery/Bariatric Center of the First Affiliated Hospital of Jinan University from October 2017 to January 2020 were included. A total of 52 male patients with obesity were included in this study. The mean age, body weight, BMI, and total testosterone level were (29.3±10.2) years, (123.6±35.4) kg, (40.1±11.1) kg/m², and 7.6 (5.5, 9.1) nmol/L, respectively. Forty-five patients (86.5%) exhibited testosterone deficiency. Among all the patients, 29 underwent LSG (LSG group) and 23 underwent LRYGB surgery (LRYGB group). The main outcome measure was the change in sex hormone levels before and after bariatric surgery in all the patients. The secondary outcome measures were the comparison of changes in sex hormone levels before and after LSG and LRYGB. Results: Pearson correlation analysis showed that preoperative estradiol was positively correlated with waist circumference (R=0.299, P<0.05), hip circumference (R=0.326, P<0.05), and chest circumference (R=0.388, P<0.05). Testosterone was negatively correlated with BMI (R=-0.563, P<0.01), waist circumference (R=-0.521, P<0.01), hip circumference (R=-0.456, P<0.01), chest circumference (R=-0.600, P<0.01), and neck circumference (R=-0.547, P<0.01). One year following bariatric surgery, the serum testosterone (7.6 [5.5, 9.1] nmol/L vs. 13.6 [10.5, 15.4] nmol/L, Z=-5.910, P<0.001), follicle-stimulating hormone (4.7 [2.7, 5.3] IU/L vs. 6.5 [3.6, 7.8] IU/L, Z=-4.658, P<0.001), and progesterone (1.2 [0.4, 1.5] nmol/L vs. 1.9 [0.8, 1.3] nmol/L, Z=-2.542, P=0.011) levels were significantly higher in all the patients. Both estradiol (172.8 [115.6, 217.5] pmol/L vs. 138.3 [88.4, 168.1] pmol/L, Z=-2.828, P=0.005) and prolactin (11.4 [6.4, 14.6] mIU/L vs. 8.6 [4.8, 7.3] mIU/L, Z=-2.887, P=0.004) levels were decreased. In addition to prolactin levels in the LRYGB group, there were statistically significant differences in the levels of estradiol (P=0.030), follicle-stimulating hormone (P < 0.001), luteinizing hormone (P=0.033), progesterone (P=0.034), and testosterone (P<0.001) compared with their preoperative levels. In the LSG group, there were statistically significant differences in the levels of follicle-stimulating hormone (P=0.011), prolactin (P=0.023), and testosterone (P<0.001) compared with their preoperative levels. Conclusion: The degree of obesity in men was negatively correlated with testosterone levels. Both LRYGB and LSG can significantly improve sex hormone levels in male patients with obesity, and testosterone levels show a significant increase after surgery.

The first case of monkeypox virus infection detected in Taiwan: awareness and preparation

OBJECTIVES

Monkeypox has recently been detected outside African countries. This study aimed to report and analyze the first case of monkeypox virus infection in Taiwan.

METHODS

The global epidemiological information was collected from the World Health Organization (WHO) and US Centers for Disease Control and Prevention (CDC). The data from the first confirmed Taiwanese monkeypox case was obtained from Taiwan Centers for Disease Control. Monkeypox diagnosis and prevention strategies were obtained from WHO guidelines on monkeypox. Phylogenetic tree analysis and sequence alignment and comparison were used to identify the phylogeny and single nucleotide polymorphism (SNP) characterization.

RESULTS

Epidemiological data indicated that since 2013, monkeypox has caused outbreaks outside African countries through contact with infected animals and international travels. Recently, two confirmed monkeypox cases were reported in Singapore and South Korea. On June 24, 2022, Taiwan CDC reported the first confirmed case of monkeypox virus infection in a 20-year-old man who returned from Germany, from January to June 2022. This is the third confirmed case of an imported monkeypox infection in Asia. Phylogenetic analysis demonstrated that this imported monkeypox virus belonged to the West African clade and is clustered with the 2022 European outbreak monkeypox isolates. Full-length sequence analysis indicates that this virus contains 51 SNPs, and has five variant SNPs compared with the recent outbreak strains.

CONCLUSION

This study suggests that active surveillance, enhancing border control, and the development of vaccines and antiviral drugs are urgently required to prevent and control the burden of monkeypox disease.

Targets and strategies for vaccine development against dengue viruses

Dengue virus (DENV) is a global health threat causing about half of the worldwide population to be at risk of infection, especially the people living in tropical and subtropical area. Although the dengue disease caused by dengue virus (DENV) is asymptomatic and self-limiting in most people with first infection, increased severe dengue symptoms may be observed in people with heterotypic secondary DENV infection. Since there is a lack of specific antiviral medication, the development of dengue vaccines is critical in the prevention and control this disease. Several targets and strategies in the development of dengue vaccine have been demonstrated. Currently, Dengvaxia, a live-attenuated chimeric yellow-fever/tetravalent dengue vaccine (CYD-TDV) developed by Sanofi Pasteur, has been licensed and approved for clinical use in some countries. However, this vaccine has demonstrated low efficacy in children and dengue-naïve individuals and also increases the risk of severe dengue in young vaccinated recipients. Accordingly, many novel strategies for the dengue vaccine are under investigation and development. Here, we conducted a systemic literature review according to PRISMA guidelines to give a concise overview of various aspects of the vaccine development process against DENVs, mainly targeting five potential strategies including live attenuated vaccine, inactivated virus vaccine, recombinant subunit vaccine, viral-vector vaccine, and DNA vaccine. This study offers the comprehensive view of updated information and current progression of immunogen selection as well as strategies of vaccine development against DENVs.

The Antiviral Role of Galectins toward Influenza A Virus Infection-An Alternative Strategy for Influenza Therapy

Animal lectins are proteins with carbohydrate recognition activity. Galectins, the β-galactoside binding lectins, are expressed in various cells and have been reported to regulate several immunological and physiological responses. Recently, some galectins have been reported to regulate some viral infections, including influenza A virus (IAV); however, the mechanism is still not fully understood. Thus, we aim to review systemically the roles of galectins in their antiviral functions against IAVs. The PRISMA guidelines were used to select the eligible articles. Results indicated that only Galectin-1, Galectin-3, and Galectin-9 were reported to play a regulatory role in IAV infection. These regulatory effects occur extracellularly, through their carbohydrate recognition domain (CRD) interacting with glycans expressed on the virus surface, as well as endogenously, in a cell-cell interaction manner. The inhibition effects induced by galectins on IAV infection were through blocking virus-host receptors interaction, activation of NLRP-3 inflammasome, augment expression of antiviral genes and related cytokines, as well as stimulation of Tim-3 related signaling to enhance virus-specific T cells and humoral immune response. Combined, this study concludes that currently, only three galectins have reported antiviral capabilities against IAV infection, thereby having the potential to be applied as an alternative anti-influenza therapeutic strategy.

Regulatory roles of galectins on influenza A virus and their potential as a therapeutic strategy

Galectins, are β-galactoside binding lectins expressed in numerous cells and are known to regulate various immune responses and cellular physiological functions. Galectins have been reported to participate in the regulation of several viral infections via carbohydrate‑dependent/independent manner. Galectins have displayed various regulatory functions on viral infection, however, the detailed mechanism remains unclear. More recently, some members of galectins have been reported to regulate influenza A virus (IAV) infection. In this review, we aim to analyze and summarize current findings regarding the role of galectins in IAV infection and their antiviral potential therapeutic application in the treatment of IAVs. The eligible articles were selected according to the PRISMA guidelines. Results indicate that Galectin-1(Gal-1), Galectin-3(Gal-3) and Galectin-9 (Gal-9) were found as the predominant galectins reported to participate in the regulation of IAVs infection. The inhibitory regulation of IAVs by these galectins occurred mainly through extracellular binding to glycosylated envelope proteins, further blocking the interaction between influenza envelope and sialic acid receptor, interacting with ligands or receptors on immune cells to trigger immunol or cellular response against IAVs, and endogenously interacting cellular components in the cytoplasm to activate inflammasome and autophagy. This study offers information regarding the multiple roles of galectins observed in IAVs infection and suggest that galectins has the potential to be used as therapeutic agents for IAVs.

[Molecular epidemiology of Listeria monocytogenes isolated from ready-to-eat food in 2017 in China]

Objective: To analyze the molecular characteristics of Listeria monocytogenes strains from ready-to eat food in China. Methods: A total of 239 Listeria monocytogenes strains isolated from ready-to-eat food in 2017, all strains underwent whole-genome sequencing (WGS) , and comparisons uncovered population structure derived from lineages, clonal complex, serogroups, antimicrobial susceptibility and virulence, which were inferred in silico from the WGS data. Core genome multilocus sequence typing was used to subtype isolates. Results: All strains were categorized into three different lineages, lineage Ⅱ was the predominant types in food, and IIa was the main serogroups. CC8, CC101 and CC87 were the first three prevalent CCs among 23 detected CCs, accounting for 49.4%. Only 4.6% (11 isolates) of tested strains harbored antibiotic resistance genes, which were mostly trimethoprim genes (7 isolates, 2.9%). All strains were positive for LIPI-1, and only a part of strains harbored LIPI-3 and LIPI-4, accounting for 13.8% (33 isolates) and 14.2% (34 isolates), respectively. ST619 carried both LIPI-3 and LIPI-4. 51.5% (123 isolates) of strains carried SSI-1, and all CC121 strains harbored SSI-2. Different lineages, serogroups and CCs can be separated obviously through cgMLST analysis, and 24 sublineages were highly concordant with CCs. Conclusion: Ⅱa was the main serogroups in ready-to-eat food isolates in China; CC8, CC101 and CC87 were the prevalent CCs, and CC87 isolates was hypervirulent isolates, cgMLST method can be adopted for prospective foodborne disease surveillance and outbreaks detection.

[The impact of different doses of atorvastatin on plasma endothelin and platelet function in acute ST-segment elevation myocardial infarction after emergency percutaneous coronary intervention]

Objective: To investigate the effects of different doses of atorvastatin on plasma endothelin and platelet function in acute ST-segment elevation myocardial infarction (STEMI) patients after emergency percutaneous coronary intervention(PCI). Methods: A total of 120 patients with acute STEMI treated with emergency PCI were enrolled and randomly divided into 20 mg of atorvastatin treatment group (standard group, n=60), and 40 mg of atorvastatin treatment group (intensive group, n=60). The blood C reactive protein (CRP), blood lipid profiles, plasma endothelin (ET) were measured before atorvastatin treatment and after 7 days of treatment, respectively. The platelet fibrin clot strength induced by ADP (MAADP) was determined by thrombelastography(TEG). Results: Seven days after of atorvastatin treatment, the level of plasma ET in intensive group was significantly lower than that in standard group [(0.49±0.21)pmol/L vs (0.63±0.58)pmol/L, P<0.05]. Moreover, the MAADP in intensive group was significantly decreased compared with the standard group [(38.4±17.4) mm vs (45.7±14.5) mm, P<0.05]. There was a positive correlation between the ET level and MAADP in intensive group after treatment (r=0.378, P<0.05). However, no significantly differences could be viewed in the CRP and LDL-C levels between the two groups (P>0.05). Conclusion: In patients with acute STEMI, early administration of 40 mg atorvastatin after emergency PCI could significantly reduce the vascular endothelial injury, improve endothelial function, and reduce the residual platelet activity.

Evaluation of coarsely ground wheat as a replacement for ground corn in the diets of lactating dairy cows

Eight multiparous Holstein cows (569±47 kg of BW; 84±17 DIM) were used to evaluate the effects of different levels of coarsely ground wheat (CGW) as replacements for ground corn (GC) in diets on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites profiles in dairy cows. The cows were settled in a replicated 4×4 Latin square design with 3-wk treatment periods; four cows in one of the replicates were fitted with rumen cannulas. The four diets contained 0, 9.6, 19.2, and 28.8% CGW and 27.9, 19.2, 9.6, and 0% GC on dry matter (DM) basis, respectively. Increasing dietary levels of CGW, daily DM intake tended to increase quadratically (p = 0.07); however, apparent digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were significantly decreased (p<0.01) in cows fed the 28.8% CGW diets. Ruminal pH remained in the normal physiological range for all dietary treatments at all times, except for the 28.8% CGW diets at 6 h after feeding; moreover, increasing dietary levels of CGW, the daily mean ruminal pH decreased linearly (p = 0.01). Increasing the dietary levels of CGW resulted in a linear increase in ruminal propionate (p<0.01) and ammonia nitrogen (NH3-N) (p = 0.06) concentration, while ruminal acetate: propionate decreased linearly (p = 0.03) in cows fed the 28.8% CGW diets. Milk production was not affected by diets; however, percentage and yield of milk fat decreased linearly (p = 0.02) when the level of CGW was increased. With increasing levels of dietary CGW, concentrations of plasma beta-hydroxybutyric acid (BHBA) (p = 0.07) and cholesterol (p<0.01) decreased linearly, whereas plasma glucose (p = 0.08), insulin (p = 0.02) and urea nitrogen (p = 0.02) increased linearly at 6 h after the morning feeding. Our results indicate that CGW is a suitable substitute for GC in the diets of dairy cows and that it may be included up to a level of 19.2% of DM without adverse effects on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites if the cows are fed fiber-sufficient diets.

Nucleocytoplasmic transport blockage by SV40 peptide-modified gold nanoparticles induces cellular autophagy

Gold nanoparticles modified with the nuclear localization signal from simian virus 40 large T antigen (GNP-PEG/SV40) accumulate on the cytoplasmic side of the nuclear membrane in HeLa cells. Accumulation of GNP-PEG/SV40 around the nucleus blocks nucleocytoplasmic transport and prevents RNA export and nuclear shuttling of signaling proteins. This long-term blockage of nucleocytoplasmic transport results in cell death. This cell death is not caused by apoptosis or necrosis because caspases 3 and 9 are not activated, and the expression of annexin V/propidium iodide is not enhanced in HeLa cells after treatment. Using transmission electron microscopy, autophagosomes and autolysosomes were seen to appear after 72 hours of treatment with GNP-PEG/SV40. Increasing levels of enhanced green fluorescent protein-microtubule-associated protein 1 light chain 3 (EGFP-LC3)-positive punctate and LC3-II confirmed GNP-PEG/SV40-induced autophagy. In SiHa cells, treatment did not induce accumulation of GNP-PEG/SV40 around the nucleus and autophagy. Treating cells with wheat germ agglutinin, a nuclear pore complex inhibitor, induced autophagy in both HeLa and SiHa cells. GNP-PEG/SV40-induced autophagy plays a role in cell death, not survival, and virus-mediated small hairpin RNA silencing of Beclin-1 attenuates cell death. Taken together, the results indicate that long-term blockade of nucleocytoplasmic transport results in autophagic cell death.

Distortionless light pulse delay in quantum-well Bragg structures

We describe a reflection scheme that allows Bragg-spaced semiconductor quantum wells to be used to trap, store, and release light. We study the temporal and spectral distortion of delayed light pulses and show that this geometry allows multibit delays and offers a high degree of distortion compensation.

Evidence for intervalence band coherences in semiconductor quantum wells via coherently coupled optical Stark shifts

We report the experimental observation of coherently coupled heavy-hole-light-hole Stark shifts, i.e., light-hole exciton shifts under heavy-hole exciton pumping conditions, in InGaAs quantum wells. The theoretical analysis of the data is based on a full many-body approach (dynamics-controlled truncation formalism) in the third-order nonlinear optical regime. It is shown that the Stark shift data can be interpreted as strong evidence of suitably defined nonradiative intervalence band coherences in a semiconductor quantum well. Hence, the observations establish a semiconductor analog of Raman coherences in three-level atoms.

[A study on phage analysis of two episodes of food poisoning caused by the same serotype of enteroinvasive Escherichia coli]

The strains of EIEC serotype O28ac:K73 (B):H-were isolated from two episodes of food poisoning in Beijing during July to September in 1984. All strains were examined by E. coli K12 and found that they possessed the ability to produce the same colicin and same phage sensitivity pattern to eight phages isolated from contaminated water in Beijing area. These characteristics were different from reserved strains O28ac and other strains of E. coli. It indicated that two episodes were caused by the same phage type of O28ac:K73 (B):H-and proved the local outbreak was caused by same strain in western area of Beijing. The authors discussed in detail. The differentiation methods for plaque formation produced by colicin and phage.

[The discovery and study on invasive strain of Escherichia coli O121]

A strain of Enteroinvasive Escherichia coli was isolated from the stool with blood and mucus of a child suffering from acute diarrhea. The strain shows the following characteristics: rapid fermentation of glucose (with gas), no fermentation of lactose, beta-galactosidase reaction positive, growth in acetate media, lysine decarboxylase negative, non-motility causing keratoconjunctivitis in guinea pigs and invading into epithelial cells, with a plasmid of 140 Md, Serotype is O121:H- which is a new serotype of Enteroinvasive Escherichia coli.

[Serotypes of enteroinvasive Escherichia coli in China]

results of identification and serotyping of enteroinvasive escherichia in china from 13 provinces in China in 1984-85 were reproted.

Monoclonal antibodies to outer membrane antigens of Vibrio cholerae

Hybridoma-derived monoclonal antibodies were prepared against outer membrane antigens of four strains of Vibrio cholerae that were cultivated under iron-limited conditions, and these antibodies were partially characterized. We established a library of 66 hybridomas which produced monoclonal antibodies defining 16 different V. cholerae antigens. Two antigens (molecular weights, 18,000 and 112,000) were heat modifiable, whereas the reacting epitope of a third antigen (40,000-dalton-18,000-dalton doublet) was completely destroyed when it was heated at 100 degrees C. The 112,000-dalton heat-modifiable protein was an iron-regulated outer membrane protein. This protein bound 59Fe in vitro when it was combined with the V. cholerae siderophore-iron complex 59Fe-vibriobactin; it was also found in in vivo grown V. cholerae, as were three other antigens. A total of 26 hybridomas produced antibody to V. cholerae lipopolysaccharide. Of these, 12 were cross-reactive with lipopolysaccharides of other gram-negative bacteria, including 2 which recognized lipid A. Several of these anti-lipopolysaccharide monoclonal antibodies appeared to be lipopolysaccharide region specific. Some membrane antigens were strain specific, whereas others were common to both O group 1 and non-O group 1 vibrios.

Rapid latex particle agglutination test for Escherichia coli strains of porcine origin producing heat-labile enterotoxin

A latex particle agglutination test previously shown to be suitable for the rapid identification of Escherichia coli strains of human origin producing heat-labile enterotoxin (R. A. Finkelstein and Z. Yang, J. Clin. Microbiol. 18:23-28) is equally applicable to strains of porcine origin.