RhoGDIß inhibition via miR-200c/AUF1/SOX2/miR-137 axis contributed to lncRNA MEG3 downregulation-mediated malignant transformation of human bronchial epithelial cells.

Nickel pollution is a recognized factor contributing to lung cancer. Understanding the molecular mechanisms of its carcinogenic effects is crucial for lung cancer prevention and treatment. Our previous research identified the downregulation of a long noncoding RNA, maternally expressed gene 3 (MEG3), as a key factor in transforming human bronchial epithelial cells (HBECs) into malignant cells following nickel exposure. In our study, we found that deletion of MEG3 also reduced the expression of RhoGDIß. Notably, artificially increasing RhoGDIß levels counteracted the malignant transformation caused by MEG3 deletion in HBECs. This indicates that the reduction in RhoGDIß contributes to the transformation of HBECs due to MEG3 deletion. Further exploration revealed that MEG3 downregulation led to enhanced c-Jun activity, which in turn promoted miR-200c transcription. High levels of miR-200c subsequently increased the translation of AUF1 protein, stabilizing SOX2 messenger RNA (mRNA). This stabilization affected the regulation of miR-137, SP-1 protein translation, and the suppression of RhoGDIß mRNA transcription and protein expression, leading to cell transformation. Our study underscores the co-regulation of RhoGDIß expression by long noncoding RNA MEG3, multiple microRNAs (miR-200c and miR-137), and RNA-regulated transcription factors (c-Jun, SOX2, and SP1). This intricate network of molecular events sheds light on the nature of lung tumorigenesis. These novel findings pave the way for developing targeted strategies for the prevention and treatment of human lung cancer based on the MEG3/RhoGDIß pathway.

Studying an off-axis optical bench for future gravity missions from the perspective of carrier-to-noise ratio.

The inter-satellite laser ranging heterodyne interferometer is vital for future gravity missions to achieve high ranging accuracy. This paper proposes a novel off-axis optical bench design which integrates merits of the off-axis optical bench design of GRACE Follow-On mission and other on-axis designs. This design makes use of lens systems subtly to restrict the tilt-to-length coupling noise and takes advantage of the DWS feedback loop to maintain the transmitting beam and receiving beam anti-parallel. The critical parameters of the optical components are determined and the carrier-to-noise ratio for a single channel of the photoreceiver is calculated to be more than 100 dB-Hz for the high case. The off-axis optical bench design is a potential candidate for China's future gravity missions.

All-electrical monitoring of bacterial antibiotic susceptibility in a microfluidic device.

The lack of rapid antibiotic susceptibility tests adversely affects the treatment of bacterial infections and contributes to increased prevalence of multidrug-resistant bacteria. Here, we describe an all-electrical approach that allows for ultrasensitive measurement of growth signals from only tens of bacteria in a microfluidic device. Our device is essentially a set of microfluidic channels, each with a nanoconstriction at one end and cross-sectional dimensions close to that of a single bacterium. Flowing a liquid bacteria sample (e.g., urine) through the microchannels rapidly traps the bacteria in the device, allowing for subsequent incubation in drugs. We measure the electrical resistance of the microchannels, which increases (or decreases) in proportion to the number of bacteria in the microchannels. The method and device allow for rapid antibiotic susceptibility tests in about 2 h. Further, the short-time fluctuations in the electrical resistance during an antibiotic susceptibility test are correlated with the morphological changes of bacteria caused by the antibiotic. In contrast to other electrical approaches, the underlying geometric blockage effect provides a robust and sensitive signal, which is straightforward to interpret without electrical models. The approach also obviates the need for a high-resolution microscope and other complex equipment, making it potentially usable in resource-limited settings.

Recent Advancements in Sensor Technologies for Healthcare and Biomedical Applications.

Biomedical sensors are the key units of medical and healthcare systems [...].

Single-Element Dual-Interferometer for Precision Inertial Sensing: Sub-Picometer Structural Stability and Performance as a Reference for Laser Frequency Stabilization.

Future GRACE-like geodesy missions could benefit from adopting accelerometer technology akin to that of the LISA Pathfinder, which employed laser interferometric readout at the sub-picometer level in addition to the conventional capacitive sensing, which is at best at the level of 100 pm. Improving accelerometer performance holds great potential to enhance the scientific output of forthcoming missions, carrying invaluable implications for research in climate, water resource management, and disaster risk reduction. To reach sub-picometer displacement sensing precision in the millihertz range, laser interferometers rely on suppression of laser-frequency noise by several orders of magnitude. Many optical frequency stabilization methods are available with varying levels of complexity, size, and performance. In this paper, we describe the performance of a Mach-Zehnder interferometer based on a compact monolithic optic. The setup consists of a commercial fiber injector, a custom-designed pentaprism used to split and recombine the laser beam, and two photoreceivers placed at the complementary output ports of the interferometer. The structural stability of the prism is transferred to the laser frequency via amplification, integration, and feedback of the balanced-detection signal, achieving a fractional frequency instability better than 6 parts in 1013, corresponding to an interferometer pathlength stability better than 1pm/Hz. The prism was designed to host a second interferometer to interrogate the position of a test mass. This optical scheme has been dubbed "single-element dual-interferometer" or SEDI.

Clonorchis sinensis Reinfection Rate and Reinfection Determinants: A Prospective Cohort Study in Hengxian County, Guangxi, China.

BACKGROUND: To understand Clonorchis sinensis reinfection and the determinants of reinfection in endemic areas is important in establishment of control measures. METHODS: A prospective cohort study was implemented in Hengxian County, Guangxi, China. Individuals with C. sinensis infection were completely treated, and those cured were enrolled as study subjects and followed up for 3, 6, and 12 months. The reinfection frequency and incidence were calculated, and a multivariable Cox proportional hazard model was constructed to capture reinfection determinants. RESULTS: Among 635 enrolled subjects, 436 (68.7%) completed follow-up. Of these, 177 (40.6%) were reinfected; 133 (75.1%) were reinfected once, 41 (23.2%) twice, and 3 (1.7%) three times. The incidence of reinfection was 64.0 per 100 person-years. Men (adjusted hazard ratio [aHR], 1.67; 95% confidence interval [CI], 1.14-2.44), those with underlying diseases (aHR, 1.41; 95% CI, 1.02-1.95), and those with moderate- or heavy-intensity infections (aHR, 1.45; 95% CI, 1.14-1.85) had increasing reinfection probabilities. CONCLUSIONS: C. sinensis reinfection is high in endemic areas. Men and high-intensity infection are important determinants of reinfection. Repeated chemotherapy is necessary to control reinfection and its associated morbidities, especially in high-risk individuals. In addition, behavioral education is advised to decrease overall reinfection in endemic areas.

Epidemiological characterization of Clonorchis sinensis infection in humans and freshwater fish in Guangxi, China.

BACKGROUND: Clonorchiasis is a widespread yet neglected foodborne disease with over 85% of all cases found in China. Guangxi province, located in southeastern China, ranks among the highest endemic provinces. We explore the epidemiological status and determinants of Clonorchis sinensis (C. sinensis) infection in humans and freshwater fish in Guangxi, China. METHODS: Data on C. sinensis infection in humans from January 2008 to December 2017were extracted from the China Information System for Disease Control and Prevention. An active surveillance of C. sinensis infection in fish was conducted in 2016-2017. County level data including potential environmental, social-economical and behavioral determinants was also collected. Univariate and multivariate logistic regression models were used to explore the determinants of C. sinensis infection in humans and fish. Simple and multiple zero-inflated Poisson regression models were fit to assess the associated factors of clonorchiasis in humans at the county level. RESULTS: Totally, 4526 C. sinensis cases were reported between 2008 and 2017, with an annual prevalencerate of 0.96/100,000 persons. Of 101 counties in Guangxi, 97 reported at least 1 case. Among 2,098 fish samples, 203 (9.7%) from 70 counties contained C. sinensis. The rate was higher in small fish including Pseudorasbora parva (45.3%), Misgurnus anguillicaudatus (41.2%), Hemicculter leuciclus (34.5%), unclassified small fishes (30.9%), Cyprinidae (20.0%), Cirrhinus molitorella (16.4%), Carassius auratus (13.6%) and Cyprinus carpio (13.3%), while it was lower in fish species that are usually used in preparing raw fish dishes including Ctenopharyngodon idellus (3.6%), Spinibarbus denticulatus (3.7%), Monopterus albus (6.4%), Cyprinus carpio (4.4%), Oreochromis mossambicus (3.3%) and Spualiobarbus Curriculus (6.6%). The C. sinensis infection in fish was only associated with fish species. The estimated human clonorchiasis prevalence at the county level was positively associated with raw fish consumption habits and certain rivers. CONCLUSIONS: Clonorchiasis is highly prevalent in both humans and freshwater fish in Guangxi. Environmental, social-economic and behavioral determinants contribute to the high prevalence as well as the significant differential distribution by county. Regular surveillance should be implemented for clonorchiasis to demonstrate the change in epidemiology and burden, which will benefit the design of interventions.

Automatic digital optical heterodyne phase locking loop in the milliradian domain for spaceborne laser interferometry.

We developed a digital optical phase locking loop (OPLL) with three advantages, including high precision of phase locking, high control bandwidth up to 2.8 MHz, and automatic laser locking strategy. Spaceborne laser interferometers will be used to measure tiny displacements caused by gravitational waves in millions of kilometers range. A slave laser will be heterodyne phase locked to the incoming weak light at the end of an arm, emitting a higher power light back to the other satellite to measure pathlength variations at the picometer level. Such accuracy requires extremely precise OPLL. We report an experiment to demonstrate a digital OPLL that can automatically lock two independent free-running Nd:YAG lasers with residual phase error below 1mrad/Hz above 0.01 Hz, which is the best performance recorded for digital servos, to our knowledge. Such performance tested under a normal laboratory environment will be highly improved in a vacuum environment with temperature and vibration well controlled. Both the digital OPLL and the automatic strategy were implemented on a field programmable gate array that could be potentially used for future gravitational-wave detection. Our experiment might change the thinking of scientists who study phasemeters of gravitational-wave detection because we are aware that the digital phase locking loop used for "optical phase tracking" is differently designed from "optical phase locking."

On-Axis Optical Bench for Laser Ranging Instruments in Future Gravity Missions.

The laser ranging interferometer onboard the Gravity Recovery and Climate Experiment Follow-On mission proved the feasibility of an interferometric sensor for inter-satellite length tracking with sub-nanometer precision, establishing an important milestone for space laser interferometry and the general expectation that future gravity missions will employ heterodyne laser interferometry for satellite-to-satellite ranging. In this paper, we present the design of an on-axis optical bench for next-generation laser ranging which enhances the received optical power and the transmit beam divergence, enabling longer interferometer arms and relaxing the optical power requirement of the laser assembly. All design functionalities and requirements are verified by means of computer simulations. A thermal analysis is carried out to investigate the robustness of the proposed optical bench to the temperature fluctuations found in orbit.

Development and application of a method to detect 27 respiratory pathogens using multiplex RT-PCR combined with MassARRAY technology.

BACKGROUND: Respiratory tract infections are the most common infections that lead to morbidity and mortality worldwide. Early recognition and precise diagnosis of microbial etiology is important to treat LRTIs promptly, specifically and effectively. OBJECTIVES: To establish a method based on multiplex reverse transcription (MRT)-PCR and MassARRAY technology for the simultaneous detection of 27 respiratory pathogens and explore its clinical application value. METHODS: Analytical sensitivity and specificity of the MRT-PCR-MassARRAY system were validated using inactivated bacterial and viral strains. Also we analyzed samples from 207 patients by MassARRAY methods and compared the results with consensus PCR/reverse transcription (RT)-PCR. RESULTS: The minimum detection limit of our MRT-PCR-MassARRAY method for pathogens was 10-100 copies/µl, with high specificity. Comparison test with consensus PCR/RT-PCR on 207 clinical samples, the positive, negative, and total correlation rates were 100, 98.68, and 99.03%, respectively. There was a high degree of agreement between the test results of the two methods (P < 0.01 by McNemar's test). CONCLUSION: Our detection system of 27 respiratory pathogens based on MassARRAY technology has high sensitivity and specificity, high throughput, and is simple to operate. It provides diagnostic value for the clinical diagnosis of respiratory pathogens and is of great significance in the screening of respiratory pathogens.

Variations in bacterial community structure and antimicrobial resistance gene abundance in cattle manure and poultry litter.

Cattle manure and poultry litter are widely used as fertilizers as they are excellent sources of nutrients; however, potential adverse environmental effects exist during land applications, due to the release of zoonotic bacteria and antimicrobial resistance (AMR) genes. This study was conducted to understand linkages between physiochemical composition, bacterial diversity, and AMR gene presence of cattle manure and poultry litter using quantitative polymerase chain reaction to enumerate four AMR genes (ermB, sulI, intlI, and blactx-m-32), Illumina sequencing of the 16 S region, and analysis of physical and chemical properties. Principal coordinate analysis of Bray-Curtis distance revealed distinct bacterial community structures between the two manure sources. Greater alpha diversity occurred in cattle manure compared to poultry litter (P < 0.05). Redundancy analysis showed a strong relationship between manure physiochemical and composition and bacterial abundance, with positive relationships occurring among electrical conductivity and carbon/nitrogen, and negative associations for total solids and soluble fractions of heavy metals. Cattle manure exhibited greater abundance of macrolide (ermB) and sulfonamide (sulI) resistant genes. Consequently, fresh cattle manure applications may result in greater potential spread of AMR genes to the soil-water environment (relative to poultry litter) and novel best management strategies (such as composting) may reduce the release of AMR genes to the soil-water environment.

Single-Element Dual-Interferometer for Precision Inertial Sensing.

Tracking moving masses in several degrees of freedom with high precision and large dynamic range is a central aspect in many current and future gravitational physics experiments. Laser interferometers have been established as one of the tools of choice for such measurement schemes. Using sinusoidal phase modulation homodyne interferometry allows a drastic reduction of the complexity of the optical setup, a key limitation of multi-channel interferometry. By shifting the complexity of the setup to the signal processing stage, these methods enable devices with a size and weight not feasible using conventional techniques. In this paper we present the design of a novel sensor topology based on deep frequency modulation interferometry: the self-referenced single-element dual-interferometer (SEDI) inertial sensor, which takes simplification one step further by accommodating two interferometers in one optic. Using a combination of computer models and analytical methods we show that an inertial sensor with sub-picometer precision for frequencies above 10 mHz, in a package of a few cubic inches, seems feasible with our approach. Moreover we show that by combining two of these devices it is possible to reach sub-picometer precision down to 2 mHz. In combination with the given compactness, this makes the SEDI sensor a promising approach for applications in high precision inertial sensing for both next-generation space-based gravity missions employing drag-free control, and ground-based experiments employing inertial isolation systems with optical readout.

A novel polysaccharide isolated from Flammulina velutipes, characterization, macrophage immunomodulatory activities and its impact on gut microbiota in rats.

The structural characteristics of a novel Flammulina velutipes polysaccharide (FVP2) were explored in this study. Besides, immunomodulatory activities of FVP2 on RAW 264.7 cell and its impact on gut microbiota in rats were investigated. FVP2 has a molecular weight of 18.3 kD, and its main components include galactose (19.96%), glucose (60.66%) and mannose (19.38%). By NMR analysis, the main-chain structure consisted of (1 â†’ 3)-linked-ß-D-Gal, (1 â†’ 6) -linked-ß-D-Gal, (1 â†’ 6)-linked-α-D-Glc and (1 â†’ 3,6)-linked-α-D-Man was identified. Results of the in vitro assays on RAW 264.7 murine macrophage cells showed FVP2 could significantly up-regulate the expression of NO, TNF-α and IL-6. FVP2 was intragastrically administered to rats for 2 weeks. Compared with the control group, two caecal short-chain fatty acids (SCFAs) concentration (isobutyric acid and butyric acid) and the abundance of beneficial microbiota of the FVP2-treated group were significantly increased (p < .05) respectively. The results demonstrated that FVP2 could effectively enhance the level of butyric acid and increase beneficial gut microbiota, which could improve the intestinal barrier function and maintain the intestinal mucosal integrity, suggesting that FVP2 could potentially be an immunomodulators or a functional food to promote intestinal health.

K13-propeller gene polymorphisms of Plasmodium falciparum and the therapeutic effect of artesunate among migrant workers returning to Guangxi, China (2014-2017).

BACKGROUND: The resistance of Plasmodium falciparum to artemisinin has been identified in Asia and some parts of Africa. The drug resistance of P. falciparum will be an obstacle to the successful elimination of malaria by 2025. Whole-genome sequencing of the artemisinin-resistant parasite line revealed mutations on the k13 gene associated with drug resistance in P. falciparum. To understand the artemisinin resistance of the imported P. falciparum cases from Africa, the mutations in the k13 gene in parasites from imported malaria cases in Guangxi Province were detected and the treatment efficiency of artesunate monotherapy was observed. METHODS: DNA was extracted from 319 blood samples from migrant workers with P. falciparum infection who returned to their hometown in Guangxi Province from Africa between 2014 and 2017. The k13-propeller gene was amplified by nested PCR, and sequencing, gene mutation frequency and geographic difference of imported P. falciparum cases were analysed by comparison with the wild-type strain. Of 319 patients, 158 were P. falciparum-infected and were treated with intravenous injection of artesunate and were observed, including the time of asexual stage clearance and the dose of artesunate used. RESULTS: Of the 319 P. falciparum samples, 12 samples had the k13-propeller mutation, and 11 point mutations were detected; 5 were non-synonymous mutations (T474I, A481T, A578S, V603E, G665S) and were not associated with artemisinin resistance. The clinical treatment observation showed that the median (IQR) dose of artesunate for peripheral blood parasite asexual stage clearance was 407.55 (360-510) mg, and the D3 parasite clearance rate was 70.25%, including the five k13-propeller mutations of P. falciparum. After 7 days of treatment, 98.73% of cases were cleared. Two cases were treated with artemisinin for 8 days with a 960-mg dose to completely clear the asexual parasite, but they did not have a mutation in the k13 gene. CONCLUSIONS: Five mutations of the k13-propeller gene in 319 P. falciparum samples from patients returning from Africa were identified. The frequency of the k13-propeller mutants was low, and the mutations were not strongly associated with artemisinin resistance. The median (IQR) dose of artesunate monotherapy in actual clinical treatment to remove asexual parasite stages was 407.55 (360-510) mg, equivalent to D3-D4. Some P. falciparum cases without a k13-propeller mutation showed obvious delayed clearance of the parasite from peripheral blood. Trial registration The diagnosis of malaria and the treatment of malaria-infected patients are the routine work of Centres for Disease Control and Prevention. Information on the patients was conveyed with the patient's approval, and the research aim, methods, risks and benefits of the study were explained in detail to the patients.

Protective effect of mulberry crude extract against nonylphenol-induced thyroid disruption by inhibiting the activity of deiodinase in rats.

Nonylphenol (NP) is an endocrine-disrupting chemical (EDC) that can lead to thyroid disruption. We explored NP-induced toxicity in the rat thyroid and evaluated the mitigating effects of mulberry crude extract (MCE) on NP toxicity. First, we aimed to evaluate NP-induced thyroid disruption by dosing Sprague-Dawley (SD) rats with NP (0, 30, 90, or 270 mg/kg body weight) daily for 28 days. Second, we aimed to determine whether MCE had a detoxifying effect on NP-induced thyroid disruption by dosing SD rats with NP (270 mg/kg body weight) or/and MCE (30, 60, or 120 mg/kg body weight) daily for 28 days. We found that NP significantly inhibited free triiodothyronin (FT3) and free thyroxine (FT4) activity in rat serum (P < 0.05), but MCE intervention significantly increased FT3 and FT4 serum levels (P < 0.05). It is possible that changes in hormonal composition might trigger the TRH-TSH-TH automatic feedback loop. The activity of the three iodothyronine deiodinases increased significantly after NP-dosing (P < 0.05), but only deiodinase3 (D3) was downregulated after MCE treatment (P < 0.05). Therefore, MCE might be an effective NP-detoxification agent against thyroid disruption because it regulates D3 activity.

Clonorchis sinensis infection and co-infection with the hepatitis B virus are important factors associated with cholangiocarcinoma and hepatocellular carcinoma.

To evaluate the contributions of Clonorchis sinensis and hepatitis B virus to the development of cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC), C. sinensis and hepatitis B virus infections in 20 clinical liver cancer cases from a C. sinensis- and hepatitis B virus-epidemic region were detected. Eight cases of ICC, 11 cases of HCC and one mixed ICC and HCC case were verified by CT, pathological section and (or) observations during surgery. The C. sinensis infection was detected by stool microscopy and ELISA, and the worms and eggs found during surgery and in pathological sections also allowed for diagnoses. Hepatitis B virus infections were detected by ELISA. In the 20 cases, 18 patients were diagnosed with C. sinensis infections. Eight of the 20 patients were infected with the hepatitis B virus, and seven were co-infected with C. sinensis. In the eight ICC patients, seven were diagnosed with C. sinensis infection, and two had mixed infections with the hepatitis B virus. In the 11 HCC patients, 10 were diagnosed with C. sinensis, four had mixed infections with the hepatitis B virus, and only one HCC patient presented a single infection by the hepatitis B virus. These clinical observations revealed that C. sinensis infection and C. sinensis co-infection with the hepatitis B virus are important factors in ICC and HCC.

Spatiotemporal Expression Patterns and Antibody Reactivity of Taeniidae Endophilin B1.

Larval Taeniidae, such as metacestodes of Taenia solium, Echinococcus granulosus, and Echinococcus multilocularis, produce chronic and fatal helminthic diseases. Proper identification of these zoonotic cestodiases is often challenging and is hampered in some clinical settings. Endophilin B1 plays critical roles in the maintenance of membrane contours and endocytosis. We isolated proteins homologous to endophilin B1 from T. solium, Taenia saginata, and Taenia asiatica The three Taeniidae endophilin B1 proteins shared 92.9 to 96.6% sequence identity. They harbored a Bin1/amphiphysin/Rvs (BAR) domain and residues for a dimeric interface but lacked a SRC homology 3 (SH3) domain. Endophilin B1 showed a unique immunological profile and was abundantly expressed in the tegumental syncytium of Taeniidae metacestodes and adults. Bacterially expressed recombinant T. solium endophilin B1 (rTsMEndoB1) demonstrated a sensitivity of 79.7% (345/433 cases) for serodiagnosis of larval Taeniidae infections. The protein showed strong immune recognition patterns against sera from patients with chronic neurocysticercosis, cystic echinococcosis, or advanced-stage alveolar echinococcosis. Adult Taeniidae infections exhibited moderate degrees of positive antibody responses (65.7% [23/35 samples]). rTsMEndoB1 showed some cross-reactivity with sera from patients infected with Diphyllobothriidae (23.6% [25/106 samples]) but not with sera from patients with other parasitic diseases or normal controls. The specificity was 91.7% (256/301 samples). The positive and negative predictive values were 93.6% and 73.4%, respectively. Our results demonstrate that Taeniidae endophilin B1 may be involved in the control of membrane dynamics, thus contributing to shaping and maintaining the tegumental curvature. rTsMEndoB1 may be useful for large-scale screening, as well as for individual diagnosis and follow-up surveillance of Taeniidae infections.

First ultrastructural data on the human tapeworm Taenia asiatica eggs by scanning and transmission electron microscopy (SEM, TEM).

Humans are definitive hosts of three species of the Taenia genus, namely Taenia solium, Taenia saginata and Taenia asiatica. The relative novelty of the latter explains the lack of knowledge concerning certain relevant aspects related to this parasite, such as its definite geographical distribution and whether its eggs can infect humans or not. So far, only the eggs of T. solium are known to be infective for humans, producing cysticercosis. Although eggs contain the infective stage, the oncosphere, there is a lack of research on the ultrastructure of eggs of human taeniids. We show, for the first time, the ultrastructure of eggs of T. asiatica by means of SEM and TEM analyses. We detected all the envelopes, namely the egg shell, vitelline layer, outer embryophoric membrane, embryophore, granular layer, basal membrane, oncospheral membrane and oncospheral tegument. Hooks surrounded by myofibrils and glycogen-like particles, the two types of secretory granules of the penetration glands, as well as several nuclei and mitochondria were also revealed in the oncospheres. In addition to the already known structures in eggs from other Taenia species, the presence of two types of small vesicles is described herein, possibly corresponding to exosomes and ectosomes because of their shape and size, which could participate in the host/parasite intercellular communication.

Malaria imported from Ghana by returning gold miners, China, 2013.

During May-August 2013, a malaria outbreak comprising 874 persons in Shanglin County, China, was detected among 4,052 persons returning from overseas. Ghana was the predominant destination country, and 92.3% of malarial infections occurred in gold miners. Preventive measures should be enhanced for persons in high-risk occupations traveling to malaria-endemic countries.

Distribution and frequency of G119S mutation in ace-1 gene within Anopheles sinensis populations from Guangxi, China.

BACKGROUND: Malaria is one of the most serious vector-borne diseases in the world. Vector control is an important measure for malaria prevention and elimination. However, this strategy is under threat as disease vectors are developing resistance to insecticides. Therefore, it is important to monitor mechanisms responsible for insecticide resistance. In this study, the presence of G119S mutation in the acetyl cholinesterase-encoding gene (ace-1) was investigated in nine Anopheles sinensis populations sampled across Guangxi Zhuang Autonomous Region China. METHODS: PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) method was used to genotype each individual adult of An. sinensis. Direct sequencing of PCR products was performed to verify the accuracy of PCR-RFLP genotyping result. Population genetics analysis was conducted using Genepop programme. RESULTS: The frequencies of susceptible homozygotes, heterozygotes and resistant homozygotes in the nine populations ranged between 0-0.296, 0.143-0.500 and 0.333-0.857, respectively. Overall, a high frequency (0.519-0.929) of mutant 119S allele was observed and the genotype frequency of the ace-1 gene of An. sinensis was at Hardy-Weinberg equilibrium in each of the nine examined populations. CONCLUSION: The G119S mutation has become fixed and is widespread in An. sinensis field populations in Guangxi, China. These findings are useful in helping design strategies for An. sinensis control.