Results of serum antibody detection from patients with hemorrhagic fever with renal syndrome in Heilongjiang, 2019-2021 / 中国热带医学

@#Abstract: Objective　To detect the antibody levels of hantavirus in serum samples from patients suspected with hemorrhagic fever with renal syndrome (HFRS) in Heilongjiang Province from 2019 to 2021, and to provide scientific basis for the prevention and control of disease. Methods　Enzyme-linked immunosorbent assays (ELISA) were used to detect the IgM antibodies to hantavirus in serum samples collected from suspected patients with HFRS in the acute-phase, and IgM and IgG antibody in convalescent-phase serum samples. The positive rate of IgM antibody in acute-phase serum samples of patients in different years was analyzed with χ2 test by SPSS 19.0, and the data were sorted out and analyzed about patients' gender, occupation, age, date of onset and interval from onset to initial diagnosis by EpiData 3.1, Excel 2003 software. Results　A total of 351 acute-phase serum samples and 208 convalescent-phase serum samples were detected in patients suspected with HFRS, respectively. There were 317 positive IgM antibodies of serum samples in the acute stage, with the positive rate of 90.31%. There was no significant difference in the positive rate of IgM antibodies in the acute stage between different years (χ2=0.895, P=0.639). T The IgM antibodies and IgG antibodies were positive in 32 (15.39%) and 28 (13.46%) of the convalescent-phase serum samples, respectively. Moreover, 148 patients (71.15%) were double-positive for IgM and IgG antibodies at the convalescent stage. The ratio of male to female patients was 4.56∶1, for which male patients were much more than female patients. Occupation was dominated by farmers (253 cases, 79.81%), followed by workers (19 cases, 5.99%) and the unemployed (17 cases, 5.36%), respectively. The age of patients ranged from 10 to 88 years old, with a median age of 49 years old. Most of the patients were in the age group from 30 years old to 60 years old (209 cases, 65.93%), among which the age group from 40 years old to 50 years old (86 cases, 27.13%) had the highest proportion, and the age group from 60 years old to 90 years old had a proportion of 20.18% (19 cases). May and November were the peak periods of HFRS in Heilongjiang Province. The median interval between onset and initial diagnosis was 4 days. Conclusions　There is a gap of about 10% between the clinical diagnosis of HFRS cases and the confirmed cases detected by laboratory in Heilongjiang Province from 2019 to 2021. The virus-specific detection results are important for confirming the diagnosis of local patients with HFRS.

MicroRNA-351 eases insulin resistance and liver gluconeogenesis via the PI3K/AKT pathway by inhibiting FLOT2 in mice of gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) is known as different degree glucose intolerance that is initially identified during pregnancy. MicroRNAs (miRs) may be a potential candidate for treatment of GDM. Herein, we suggested that miR-351 could be an inhibitor in the progression of GDM via the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway. Microarray analysis was used to identify differentially expressed genes and predict miRs regulating flotillin 2 (FLOT2). Target relationship between miR-351 and FLOT2 was verified. Gestational diabetes mellitus mice were treated with a series of mimic, inhibitor and small interfering RNA to explore the effect of miR-351 on insulin resistance (IR), cell apoptosis in pancreatic tissues and liver gluconeogenesis through evaluating GDM-related biochemical indexes, as well as expression of miR-351, FLOT2, PI3K/AKT pathway-, IR- and liver gluconeogenesis-related genes. MiR-351 and FLOT2 were reported to be involved in GDM. FLOT2 was the target gene of miR-351. Gestational diabetes mellitus mice exhibited IR and liver gluconeogenesis, up-regulated FLOT2, activated PI3K/AKT pathway and down-regulated miR-351 in liver tissues. Additionally, miR-351 overexpression and FLOT2 silencing decreased the levels of FLOT2, phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, fasting blood glucose, fasting insulin, total cholesterol, triglyceride, glyeosylated haemoglobin and homeostasis model of assessment for IR index (HOMA-IR), extent of PI3K and AKT phosphorylation, yet increased the levels of HOMA for islet ß-cell function, HOMA for insulin sensitivity index and glucose transporter 2 expression, indicating reduced cell apoptosis in pancreatic tissues and alleviated IR and liver gluconeogenesis. Our results reveal that up-regulation of miR-351 protects against IR and liver gluconeogenesis by repressing the PI3K/AKT pathway through regulating FLOT2 in GDM mice, which identifies miR-351 as a potential therapeutic target for the clinical management of GDM.

Efficacy of different antidiabetic drugs based on metformin in the treatment of type 2 diabetes mellitus: A network meta-analysis involving eight eligible randomized-controlled trials.

Diabetes mellitus is one of the most prevalent metabolic diseases globally and it is increasing in prevalence. It is one of the most expensive diseases with respect to total health care costs per patient as a result of its chronic nature and its severe complications. To provide a more effective treatment of type 2 diabetes mellitus (T2DM), this study aims to compare different efficacies of six kinds of hypoglycemic drugs based on metformin, including glimepiride, pioglitazone, exenatide, glibenclamide, rosiglitazone, and vildagliptin, in T2DM by a network meta-analysis that were verified by randomized-controlled trials (RCTs). Eight eligible RCT in consistency with the aforementioned six hypoglycemic drugs for T2DM were included. The results of network meta-analysis demonstrated that the exenatide + metformin and vildagliptin + metformin regimens presented with better efficacy. Patients with T2DM with unsatisfactory blood glucose control based on diet control, proper exercise, and metformin treatment were included. The original regimen and dose of medication were unchanged, followed by the addition of glimepiride, pioglitazone, exenatide, glibenclamide, rosiglitazone, and vildagliptin. The results of RCTs showed that all these six kinds of drugs reduced the HbA1c level. Compared with other regimens, exenatide + metformin reduced fasting plasma glucose (FPG), fasting plasma insulin (FPI), total cholesterol (TC), and homeostasis model assessment insulin resistance index (HOMA-IR) levels, but increased the high-density lipoprotein (HDL) level; vildagliptin + metformin decreased FPI and low-density lipoprotein (LDL) levels; glibenclamide + metformin decreased the FPG level, but promoted HDL; and glimepiride + metformin decreased the TC level and rosiglitazone + metformin reduced the LDL level. Our findings indicated that exenatide + metformin and vildagliptin + metformin have better efficacy in T2DM since they can improve insulin sensitivity.

A novel SNP in the 5' regulatory region of organic anion transporter 1 is associated with chronic kidney disease.

We aimed to analyze the associations of single nucleotide polymorphisms (SNP) in the 5' regulatory region of the human organic anion transporter 1 (OAT1) gene with chronic kidney disease (CKD). A case-control study including age- and sex-matched groups of normal subjects and patients with CKD (n = 162 each) was designed. Direct sequencing of the 5' regulatory region (+88 to -1196 region) showed that patients with CKD had a higher frequency of the -475 SNP (T > T/G) than normal subjects (14/162 vs. 2/162). The luciferase activity assay results indicated that the -475G SNP had a higher promoter efficiency than the -475T SNP. Chromatin immunoprecipitation (ChIP) and LC/MS/MS analyses showed that the -475G SNP up-regulated 26 proteins and down-regulated 74 proteins. The Southwestern blot assay results revealed that the -475G SNP decreased the binding of Hepatoma-derived growth factor (HDGF), a transcription repressor, compared to the -475T SNP. Overexpression of HDGF significantly down-regulated OAT1 in renal tubular cells. Moreover, a zebrafish animal model showed that HDGF-knockdown zebrafish embryos had higher rates of kidney malformation than wild-type controls [18/78 (23.1%) vs. 1/30 (3.3%)]. In conclusion, our results suggest that an OAT1 SNP might be clinically associated with CKD. Renal tubular cells with the -475 SNP had increased OAT1 expression, which resulted in increased transportation of organic anion toxins into cells. Cellular accumulation of organic anion toxins caused cytotoxicity and resulted in CKD.

[Characterization of S gene of a strain of hantavirus isolated from Apodemus peninsulae in Heilongjiang Province].

In order to study the molecular characterization of the hantavirus isolated from Apodemus peninsulae in Heilongjiang Province, the S gene of a new strain NA33 was amplified, sequenced and analyzed. The results showed that the complete nucleotide sequence of the S gene of NA33 strain was composed of 1 693 nucleotides with TA-rich. The S gene contained one ORF, starting at position 37 and ending at position 1 326, encoding the N protein of 429 amino acid residues, and in line with HTN-based coding. Sequence comparison of the S genes between NA33 and reference hantavirus strains showed that NA33 was more homologous to Amur-like viruses than to the Hantaan (HTN) viruses or the other hantaviruses. Phylogenetic analysis of the amino acid sequence of N proteins showed that NA33 was clustered into the group of Amur-like viruses and was more similar to Far East Russia and Jilin strains isolated from Apodemus peninsulae. The phylogenetic tree indicated a certain degree of host-dependent characteristics and geographical aggregation characteristics of hantanviruses. Furthermore, the amino acid sequence of N protein of NA33 had the conserved amino acid sites of Amur-like viruses. In conclusion, Apodemus peninsulae carried Amur-like viruses in Heilongjiang province and was an important infectious source of hemorrhagic fever with renal syndrome (HFRS).

An ester extract of Cochinchina momordica seeds induces differentiation of melanoma B16 F1 cells via MAPKs signaling.

Cochinchina momordica seeds (CMS) have been widely used due to antitumor activity by Mongolian tribes of China. However, the details of the underlying mechanisms remain unknown. In the present study, we found that an EtOAc (ethyl ester) extract of CMS (CMSEE) induced differentiation and caused growth inhibition of melanoma B16 F1 cells. CMSEE at the concentration of 5-200 µg/ml exhibited strongest anti-proliferative effects on B16 F1 cells among other CMS fractions (water or petroleum ether). Moreover, CMSEE induced melanoma B16 F1 cell differentiation, characterized by dendrite-like outgrowth, increasing melanogenesis production, as well as enhancing tyrosinase activity. Western blot analysis showed that sustained phosphorylation of p38 MAP accompanied by decrease in ERK1/2 and JNK dephosphorylation were involved in CMSEE-induced B16 F1 cell differentiation. Notably, 6 compounds that were isolated and identified may be responsible for inducing differentiation of CMSEE. These results indicated that CMSEE contributes to the differentiation of B16 F1 cells through modulating MAPKs activity, which may throw some light on the development of potentially therapeutic strategies for melanoma treatment.

[Coumarins of Anemone raddeana Regel and their biological activity].

To study the coumarins of Anemone raddeana Regel, the compounds were separated by silica gel column chromatography and HPLC. Their structures were identified by their physicochemical property and spectral analysis. Two new compounds were isolated and identified as 4, 7-dimethoxyl-5-methyl-6-hydroxy coumarin (1) and 4, 7-dimethoxyl-5-formyl-6-hydroxycoumarin (2). The bioassays indicated that compounds 1 and 2 could significantly inhibit the proliferation of cancer cell, and showed the agonist effect on the transactivity of retinoic acid receptor-alpha (RARalpha). In addition, the two compounds had inhibitory effect against human leukocyte elastase (HLE).

[New homoisoflavanones from Polygonatum odoratum (Mill.) Druce].

To study chemical constituents of Polygonatum odoratum (Mill.) Druce, the compounds were separated with column chromatography and HPLC. On the basis of physicochemical properties and spectral data, their structures were confirmed. Nine compounds were isolated and identified as 5,7-dihydroxy-6-methoxyl-8-methyl-3-(2',4'-dihydroxybenzyl)chroman-4-one (1), 5,7-dihydroxy-6-methyl-3-(2',4'-dihydroxybenzyl)chroman-4-one (2), 5,7-dihydroxy-6-methoxyl-8-methyl-3-(4'-methoxybenzyl)chroman-4-one (3), disporopsin (4), chrysoeriol (5), 5,4'-dihydroxy-7-methoxy-6-methylflavone (6), N-trans-feruloyltyramine (7), N-trans-feruloyloctopamine (8), and (+)-syringaresinol (9). Compounds 1-3 are new homoisoflavanones. Compounds 4-9 are isolated from this plant for the first time.

[Characteristic analysis of E protein genes of new strains of tick-borne encephalitis virus isolated from China].

In order to determine the characteristics and genotypes of E protein genes of tick-borne encephalitis (TBE) virus strains DXAL-5, 12,13,16,18, 21 isolated from Ixodes persulcatus in the Northeast of China, cDNA synthesis of E protein genes of the six DXAL strains was performed using RT-PCR, and the E protein genes were cloned and sequenced. The results showed that the nucleotide sequence of E protein gene of the six DXAL strains was 1488 bp in length respectively and the length of predicted protein was 496 aa respectively. Sequence comparison of E protein genes among the six DXAL strains and the reference TBE virus strains showed that the six DXAL strains were more homologous to Far Eastern subtype strains than to Siberian subtype strains or European subtype strains. And the majority of subtype-determining amino acid sites of the six DXAL strains belonged to TBE virus Far Eastern subtype. Phylogenetic analysis of protein E showed that the six DXAL strains were all within the clade containing Far Eastern subtype strains. The new strains had higher identities and closer phylogenetic relationships with Senzhang strain, so we speculate that this vaccine strain still have good protection against the new TBE virus isolates. In the A, B and C antigenic domains of protein E, the six DXAL strains had different degrees of amino acid changes. These mutations were likely to affect the function of E protein.