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Background: In South Asia, the epidemiology of malaria is complex, and transmission mainly occurs in remote areas near international borders. Vector control has been implemented as a key strategy in malaria prevention for decades. A rising threat to the efficacy of vector control efforts is the development of insecticide resistance, thus it is important to monitor the type and frequency of insecticide resistant alleles in the disease vectors such as An. sinensis along the China-Vietnam border. Such information is needed to synthesize effective malaria vector control strategies. Methods: A total of 208 adults of An. sinensis, collected from seven sites in southwest Guangxi along the China-Vietnam border, were inspected for the resistance-conferring G119S mutation in acetylcholinesterase (AChE) by PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism) and kdr mutations in the voltage-gated sodium channel (VGSC) by sequencing. In addition, the evolutionary origin of An. sinensis vgsc gene haplotypes was analyzed using Network 5.0. Results: The frequencies of mutant 119S of AChE were between 0.61–0.85 in the seven An. sinensis populations. No susceptible homozygote (119GG) was detected in three of the seven sites (DXEC, LZSK and FCGDX). Very low frequencies of kdr (0.00–0.01) were detected in the seven populations, with most individuals being susceptible homozygote (1014LL). The 1014F mutation was detected only in the southeast part (FCGDX) at a low frequency of 0.03. The 1014S mutation was distributed in six of the seven populations with frequencies ranging from 0.04 to 0.08, but absent in JXXW. Diverse haplotypes of 1014L and 1014S were found in An. sinensis along the China-Vietnam border, while only one 1014F haplotype was detected in this study. Consistent with a previous report, resistant 1014S haplotypes did not have a single origin. Conclusions: The G119S mutation of AChE was present at high frequencies (0.61–0.85) in the An. sinensis populations along the China-Vietnam border, suggesting that the vector control authorities should be cautious when considering carbamates and organophosphates as chemicals for vector control. The low frequencies (0.00–0.11) of kdr in these populations suggest that pyrethroids remain suitable for use against An. sinensis in these regions. [ABSTRACT FROM AUTHOR]

Background: We present a rare case of secondary angle closure glaucoma due to systemic lupus erythematosus choroidopathy as initial presentation of systemic lupus erythematosus, accompanied by central nervous system vasculitis and uncontrolled nephropathy.Case Presentation: A 31-year-old woman presented with decreased visual acuity, nausea, vomiting, fever, and bilateral angioedema-like eyelid swelling. She had persistent dry cough while taking medication for 3 months, and had usual posterior neck pain, which was treated with analgesic medication and Asian medicines. Intraocular pressure was 32 and 34 mmHg in her right and left eyes, respectively. Peripheral anterior chambers were shallow (grade I) using the van Herick method. Gonioscopy revealed 360° closed angle in both eyes. In both eyes, serous retinal detachment was found using optical coherence tomography and B scan ultrasonography, as well as choroidal thickening with effusion. Secondary acute angle closure glaucoma was drug induced, or caused by uveitis of unknown etiology when she was first treated with intraocular pressure-lowering medication. During evaluation of the drug-induced angioedema in the internal medicine department, systemic lupus erythematosus was diagnosed, based on malar rash, photosensitivity, proteinuria, and positive anti-Smith and anti-DNA antibodies, followed by initiation of steroid pulse therapy. Using fluorescein angiography, multifocal subretinal pinpoint foci were detected at the middle phase. We then diagnosed bilateral angle closure glaucoma by choroidal effusions, with lupus choroidopathy. At 2 months after steroid pulse therapy, subretinal fluid was not found, and visual acuity improved to normal. During the subsequent 2 years, lupus choroidopathy was not aggravated but lupus nephritis was not controlled.Conclusion: Patients with systemic lupus erythematosus choroidopathy can develop ciliochoroidal effusion, which can lead to acute angle closure glaucoma. Systemic lupus erythematosus choroidopathy is an early sign of severe complications. Angle closure glaucoma by systemic lupus erythematosus choroidopathy can be effectively treated using antiglaucoma drugs and immunosuppressive therapy. [ABSTRACT FROM AUTHOR]

Background: Anopheles sinensis is a major vector of malaria in China. The gamma-aminobutyric acid (GABA)-gated chloride channel, encoded by the RDL (Resistant to dieldrin) gene, is the important target for insecticides of widely varied structures. The use of various insecticides in agriculture and vector control has inevitably led to the development of insecticide resistance, which may reduce the control effectiveness. Therefore, it is important to investigate the presence and distribution frequency of the resistance related mutation(s) in An. sinensis RDL to predict resistance to both the withdrawn cyclodienes (e.g. dieldrin) and currently used insecticides, such as fipronil., Methods: Two hundred and forty adults of An. sinensis collected from nine locations across Guangxi Zhuang Autonomous Region were used. Two fragments of An. sinensis RDL (AsRDL) gene, covering the putative insecticide resistance related sites, were sequenced respectively. The haplotypes of each individual were reconstructed by the PHASE2.1 software, and confirmed by clone sequencing. The phylogenetic tree was built using maximum-likelihood and Bayesian inference methods. Genealogical relations among different haplotypes were also analysed using Network 5.0., Results: The coding region of AsRDL gene was 1674 bp long, encoding a protein of 557 amino acids. AsRDL had 98.0% amino acid identity to that from Anopheles funestus, and shared common structural features of Cys-loop ligand-gated ion channels. Three resistance-related amino acid substitutions (A296S, V327I and T345S) were detected in all the nine populations of An. sinensis in Guangxi, with the 296S mutation being the most abundant (77-100%), followed by 345S (22-47%) and 327I (8-60%). 38 AsRDL haplotypes were identified from 240 individuals at frequencies ranging from 0.2 to 34.8%. Genealogical analysis suggested multiple origins of the 345S mutation in AsRDL., Conclusions: The near fixation of the 296S mutation and the occurrence of the 327I and 345S mutations in addition to 296S, in all the nine tested An. sinensis populations in Guangxi, strongly indicate a risk of multiple insecticide resistance. The haplotype diversity plus genetic heterogeneities in the geographical distribution, and multiple origins of AsRDL alleles call for a location-customized strategy for monitoring and management of insecticide resistance.

Background: Anopheles sinensis is a major vector of malaria in China and its control is under great threat as the development of insecticide resistance. Voltage-gated sodium channel (VGSC) is the target of several classes of insecticides. Genetic mutations of VGSC have been documented to confer knockdown resistance (kdr) to dichlorodiphenyltrichloroethane (DDT) and pyrethroids in mosquitoes. To control this vector efficiently, it is important to know the resistance-associated genetic mutations, their distribution frequencies and genealogical relations., Methods: Three hundreds and thirteen (313) adults of An. sinensis collected from nine locations across Guangxi Zhuang Autonomous Region were used. The partial sequence of the An. sinensis voltage gated sodium channel gene (AS-VGSC) containing codon 1014 was sequenced. PHASE2.1 was used to construct the haplotypes of each individual, and the accuracy of haplotypes was further confirmed by clone sequencing. The genealogical relations of kdr mutations in AS-VGSC was analysed using TCS 2.1 and Network 5.0., Results: Sixteen AS-VGSC haplotypes including seven haplotypes carrying non-synonymous mutations at codon 1014, and fifty-five AS-VGSC genotypes were identified from 313 mosquitoes collected from nine geographical locations across Guangxi. The number of haplotypes in each of the nine populations ranged from 5 to 13. The frequency of haplotypes carrying kdr mutations ranged from 2.7 to 80.0 % within the nine populations, of which 1014C was unexpectedly high in the northeast of Guangxi. Genealogical analysis suggested multiple origins of kdr mutations in An. sinensis., Conclusion: Diverse haplotypes of AS-VGSC are distributed in Guangxi. The presence of haplotypes carrying mutations at codon 1014 indicates a risk of pyrethroid and DDT resistance. The kdr mutations show differential distribution geographically, with high frequencies occurred in the northeast of Guangxi. Genealogical analysis suggests multiple origins of kdr mutations in An. sinensis populations in Guangxi. These findings have important practical implications for the sustainability of An. sinensis control programmes.

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.

Background: We present a rare case of secondary angle closure glaucoma due to systemic lupus erythematosus choroidopathy as initial presentation of systemic lupus erythematosus, accompanied by central nervous system vasculitis and uncontrolled nephropathy., Case Presentation: A 31-year-old woman presented with decreased visual acuity, nausea, vomiting, fever, and bilateral angioedema-like eyelid swelling. She had persistent dry cough while taking medication for 3 months, and had usual posterior neck pain, which was treated with analgesic medication and Asian medicines. Intraocular pressure was 32 and 34 mmHg in her right and left eyes, respectively. Peripheral anterior chambers were shallow (grade I) using the van Herick method. Gonioscopy revealed 360° closed angle in both eyes. In both eyes, serous retinal detachment was found using optical coherence tomography and B scan ultrasonography, as well as choroidal thickening with effusion. Secondary acute angle closure glaucoma was drug induced, or caused by uveitis of unknown etiology when she was first treated with intraocular pressure-lowering medication. During evaluation of the drug-induced angioedema in the internal medicine department, systemic lupus erythematosus was diagnosed, based on malar rash, photosensitivity, proteinuria, and positive anti-Smith and anti-DNA antibodies, followed by initiation of steroid pulse therapy. Using fluorescein angiography, multifocal subretinal pinpoint foci were detected at the middle phase. We then diagnosed bilateral angle closure glaucoma by choroidal effusions, with lupus choroidopathy. At 2 months after steroid pulse therapy, subretinal fluid was not found, and visual acuity improved to normal. During the subsequent 2 years, lupus choroidopathy was not aggravated but lupus nephritis was not controlled., Conclusion: Patients with systemic lupus erythematosus choroidopathy can develop ciliochoroidal effusion, which can lead to acute angle closure glaucoma. Systemic lupus erythematosus choroidopathy is an early sign of severe complications. Angle closure glaucoma by systemic lupus erythematosus choroidopathy can be effectively treated using antiglaucoma drugs and immunosuppressive therapy.