Ensuring food security requires new green pesticides. Double-stranded RNA (dsRNA) pesticides trigger RNA interference by exogenous dsRNA specifically targeting pests and diseases. They can inhibit the expression of key genes in pathogens or pests, thereby achieving effective control of specific pests and diseases. DsRNA pesticides are environmentally friendly, with strong specificity and efficient gene silencing ability, while they have problems such as high production costs. Using engineering strains to produce dsRNA is a feasible strategy, whereas currently there is no cost-effective engineering strain for producing dsRNA. This article reviews the research progress and production strategies of using microorganisms to produce dsRNA, hoping to provide reference for dsRNA production.
RNA, Double-Stranded/genetics* ; Genetic Engineering/methods* ; RNA Interference ; Pesticides ; Animals

The use of tyrosine kinase inhibitors （TKI） has been an important advance in the systemic treatment of hepatocellular carcinoma， but their sustained anti-angiogenic therapy leads to increased tumor hypoxia， accelerates the development of a hypoxic microenvironment and promotes the expressions of hypoxia-inducible factors （HIF）， thereby inducing drug resistance of tumor patients to TKI. This paper summarizes the mechanism of action of HIF mediating TKI resistance in hepatocellular carcinoma in aspects of metabolic reprogramming， abnormal expressions of cancer and cancer-associated genes， and ferroptosis， and sorts resistance response strategies to provide reference for clinical solutions to TKI resistance issues. As results show， HIF/ glycolysis axis inhibitors （isoflavonoid genistein， simvastatin， etc.） can improve TKI resistance based on metabolic reprogramming mechanism； oncogene-targeted inhibitors combined with TKI （the combination of capsaicin and sorafenib） can improve TKI resistance based on abnormal expression of cancer and cancer-related genes； fatty acid synthase inhibitor （orlistat） can improve TKI resistance based on ferroptosis mechanism.

Chemical cleaning and disinfection are crucial steps for eliminating infection in root canal treatment.However,irrigant selection or irrigation procedures are far from clear.The vapor lock effect in the apical region has yet to be solved,impeding irrigation efficacy and resulting in residual infections and compromised treatment outcomes.Additionally,ambiguous clinical indications for root canal medication and non-standardized dressing protocols must be clarified.Inappropriate intracanal medication may present side effects and jeopardize the therapeutic outcomes.Indeed,clinicians have been aware of these concerns for years.Based on the current evidence of studies,this article reviews the properties of various irrigants and intracanal medicaments and elucidates their effectiveness and interactions.The evolution of different kinetic irrigation methods,their effects,limitations,the paradigm shift,current indications,and effective operational procedures regarding intracanal medication are also discussed.This expert consensus aims to establish the clinical operation guidelines for root canal irrigation and a position statement on intracanal medication,thus facilitating a better understanding of infection control,standardizing clinical practice,and ultimately improving the success of endodontic therapy.

Objective:To identify the association of sex hormone and sex hormone-binding globulin (SHBG) levels in patients with Graves′ disease.Methods:Between December 2017 and July 2019, 152 patients with Graves′ disease were enrolled in the Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University. Parameters such as height, weight, thyroid function, sex hormone, fasting blood glucose, insulin, C-peptide, glycosylated albumin, HbA 1C, and liver function were collected. The associations between SHBG and bioclinical characteristics were analyzed. Results:The glycosylated albumin level was negatively associated with SHBG in all subjects ( β=-0.308, P<0.01), while this association was not significant after the adjustment for thyroid hormones. Male patients had significantly lower SHBG level than female patients ( P<0.01). In male patients, SHBG was associated with luteinizing hormone ( r=0.465, P<0.01), estradiol ( r=0.629, P<0.01), testosterone ( r=0.786, P<0.01). While in female patients, SHBG was also associated with testosterone ( r=0.191, P<0.05). In multivariate linear regression analysis, estradiol was independently associated with SHBG ( β=0.329, P<0.01) in male subjects. Conclusion:The hypogonadism and infertility in Graves′ disease patients could partially be attributed to the association between SHBG and Graves′ disease.

Objective To evaluate the effect of pregnancy on gastric emptying of fluid using ultrasound.Methods Thirty parturients who were at full term,aged 20-40 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,were divided into 2 groups (n=15 each) according to the liquid ingested:clear water group (N group) and carbohydrate beverage group (S group).Parturients underwent food fasting ≥8 h and water fasting≥2 h.Parturients ingested clear water 200 ml in N group and carbohydrate beverage 200 ml in S group.The antral cross-sectional area (CSA) was measured in the semi-sitting position using bedside ultrasonography in the fasting state (T0),immediately after ingesting liquids (T1),and at 30,60 and 120 min after the end of ingesting liquids (T2-4).Gastric emptying was defined as the antral CSA measured less than or equal to the antral CSA at T0.Results The rate of gastric emptying was all 100％ at T4 between two groups.Compared with group N,the rate of gastric emptying was significantly decreased at T3 in group S (P＜0.05).Conclusion Gastric emptying of fluid is achieved within 2 h after ingesting clean water or carbohydrate beverage in parturients who are at full term,and gastric emptying is delayed after ingesting carbohydrate beverage compared with that after ingesting clean water.

Objective To investigate the effects of trichostatin A(TSA)on the mice model of collagen induced arthritis(CIA).Methods Mice model of rheumatoid arthritis(RA)was induced in DBA/1 mice with type Ⅱ collagen.Paws were scored for histological severity of arthritis.The severity of inflammation of mouse joint was evaluated by histological examination.Real-time PGR was used to determine the cytokine mRNA expression.Cytokine production was measured by ELISA from serum,spleen cell culture or dendritic cell and T cell co-culture supematant.T cell proliferation was examined by MTT method.Results TSA can significantly suppress the severity of the arthritis in CIA.IFN-γ was elevated in CIA mice,but was inhibited significantly by TSA introduced either at the same time with immunization or at the onset of manifestation of arthritis.Collagen specific T cell proliferation was significantly suppressed by introduction of TSA.Increased level of IL-4 by T cells was observed in TSA treated group compared to that of control group.Conclusion IL-4 level was increased and played a critical role in the protective effects of TSA in CIA.TSA suppresses the progress of CIA by regulates the balance of Th1/Th2 differentiation.

Objective To evaluate the performance characteristics of the second trimester double-marker test for the detection of fetal Down's syndrome in mainland China. Methods This prospective national multi-centered study used alpha-fetoprotein (AFP) and free β-subunit of human chorionic gonadotrophin( free β-hCG)as the serum markers. From May 2004 to September 2006, 11 centers participated in the collection and analysis of maternal serum AFP and free β-hCG between 14 and 20+6 weeks of pregnancy. The screening results were calculated using the standard algorithm based on the standard database provided with the analytic software. Patients with an increased risk of Down's syndrome pregnancy (≥1/270) were offered genetic anmiocentesis. Outcomes of all pregnancies were obtained.Results A total of 66 132 singleton pregnancies were included in the study. The median maternal age was 27 years. At a cut-eft of 1 in 270, the detection rate (DR) based on a Caucasian database was 72% corresponding to a false positive rate (FPR) of 5%, and the DR based on the Chinese database was raised to 76% corresponding to an FPR of 5%. Conclusion The double-marker test using AFP and free β-hCG is an effective screen strategy for second-trimester detection of fetal Down's syndrome in mainland China. Ethnic variance exists between the Caucasian and Chinese populations. The accuracy of screening is increased by the use of race-specific medians.

Objeetive To evaluate the performance characteristics of the second trimester double test for the detection of fetal Down's syndrome(DS)in women of advanced maternal age(AMA).Methods We undertook a prospective nation-wide multi-centered study and chose alpha-fetoprotein(AFP))and free β-subunit of human chorionic gonadotrophin(free β-hCG)as the serum markers.Between May 2004 and September 2006,12 centers participated in the collection and analysis of maternal serum AFP and free β-hCG.Patients with an iuereaged risk of DS(≥1/270)wero offered generic sunniocentesis.Follow up of the outcome of all pregnancies was obtained.Patients were divided into two groups,the AMA group and the non-AMA group and the screening efficiency Was evaluated in beth groups.Results A total of 66 132 singleton pregnancies were included in the study.and there were 36 10(5.46%)AMA women.The median maternal age of AMA women was 36.8years(35-47 years).At a cut-off of 1/270,in the AMA group,the number of positive cases screened was 727 and 22 cases of fetal DS were detected:the number of negative cases screened was 2883,and no fetal DS was found.In the non-AMA group,the number of positive cases screened was 4743 and 69 cases of fetal DS were detected:the number of negative cases screened was 57 779,and 6 cases of fetal DS were diagnosed postnatally.In AMA group,the detection rate(DR),false positive rate(FPR)and odds of being affected given a positive result(OAPR)were 100%,19.7%and 3.0%respectively.In the non-AMA group,the DR,FPR and OAPR were 92.0%.7.5%and 1.5%respectively.Conclusion The double-marker test using AFP and free β-hCG is an effective screen strategy for second-trimester detection of Down syndrome in AMA women.