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BackgroundMass drug administration (MDA) is a powerful tool for malaria control, but the medicines to use, dosing, number of rounds, and potential selection of drug resistance remain open questions.MethodsTwo monthly rounds of artemisinin-piperaquine (AP), each comprising 2 daily doses, were administered across the 7 districts of Grande Comore Island. In 3 districts, low-dose primaquine (PMQLD) was also given on the first day of each monthly round. Plasmodium falciparum malaria rates, mortality, parasitemias, adverse events, and genetic markers of potential drug resistance were evaluated.ResultsAverage population coverages of 80%–82% were achieved with AP in 4 districts (registered population 258 986) and AP + PMQLD in 3 districts (83 696). The effectiveness of MDA was 96.27% (95% confidence interval [CI], 95.27%–97.06%; P < .00001) in the 4 AP districts and 97.46% (95% CI, 94.54%–98.82%; P < .00001) in the 3 AP + PMQLD districts. In comparative statistical modeling, the effectiveness of the 2 monthly rounds on Grande Comore Island was nearly as high as that of 3 monthly rounds of AP or AP + PMQLD in our earlier study on Anjouan Island. Surveys of pre-MDA and post-MDA samples showed no significant changes in PfK13 polymorphism rates, and no PfCRT mutations previously linked to piperaquine resistance in Southeast Asia were identified.ConclusionsMDA with 2 monthly rounds of 2 daily doses of AP was highly effective on Grande Comore Island. The feasibility and lower expense of this 2-month versus 3-month regimen of AP may offer advantages for MDA programs in appropriate settings.

Shaoqin Zheng1,2 &ast;, Yuan Liang2 &ast;, Zhaojia Wang,1 Min Liu,1 Yingyi Chen,1 Ying Ai,1 Wenfeng Guo,1,3 Guoming Li,1 Yueming Yuan,1,2 Zhiyong Xu,2 Wanting Wu,1 Xinan Huang,1,3 Zhibing Wu,3 Qin Xu,1,3 Jianping Song,1,3 Changsheng Deng1,3 1Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China; 2Science and Technology Institute, Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China; 3The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Jianping Song; Changsheng Deng, Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, 510405, People’s Republic of China, Tel +86-20-3658 5633 ; +86-20-8746 1723, Email songjp@gzucm.edu.cn; dcs19811202@163.comIntroduction: Artemisinin-based combination therapies (ACTs) act as first-line antimalarial drugs and play a crucial role in the successful control of falciparum malaria. However, the recent emergence of resistance of Plasmodium falciparum to ACTs in South East Asia is of particular concern. Hence, there is an urgent need to identify the genetic determinants of and understand the molecular mechanisms underpinning such resistance. Artemisinin resistance (AR) is primarily driven by the mutations in the P. falciparum K13 protein, which is widely recognized as the major molecular marker of AR. However, association of K13 mutations with in vivo AR has been ambiguous due to the absence of a tractable model.Methods: In this study, we have successfully produced artemisinin- and piperaquine-resistant P. berghei K173 following drug administrations. Prolonged parasite clearance and early recrudescence were found following daily exposure to high doses of artemisinin and piperaquine. We have also sequenced the DNA of artemisinin-resistant strains and piperaquine-resistant strains of P. berghei K173 to explore the relationship between PfK13 and AR.Results: The resistance index of P. berghei K173 reached 12.4 after 30 artemisinin-resistant generations, but AR declined gradually after 30 generations. On the 50th generation, the resistance index of artemisinin-resistant strains was only 5.0 compared with the severe drug resistance of piperaquine-resistant strains (I90=148.8). DNA sequencing of artemisinin-resistant strains showed that there were 9 meaningful mutations at P. berghei K13-propeller domain, but the above mutations did not include common clinical point mutations.Conclusion: Our data show that artemisinin is less susceptible to severe resistance compared with other antimalarial drugs. In addition, mutation on P. berghei K13 has a multi-drug-resistant phenotype and may be used as a biomarker to monitor its resistance. More studies need to be conducted on the new mutations detected so as to understand their association, if any, with ACT resistance.Keywords: malaria, Plasmodium berghei, P. berghei K13 gene, artemisinin resistance

Wnt/β-catenin signaling is a conserved pathway crucially governing development, homeostasis and oncogenesis. Discovery of novel regulators holds great values in both basic and translational research. Through screening, we identified a deubiquitinase (DUB) USP10 as a novel and critical modulator of β-catenin. Mechanistically, USP10 binds to key scaffold Axin1 via conserved motifs and stabilizes Axin1 through K48-linked deubiquitination, and surprisingly, tethers Axin1 and β-catenin physically while promoting phase separation for β-catenin suppression regardless of its enzymatic activity. Functionally, USP10 prominently regulates embryonic development and intestinal homeostasis by antagonizing β-catenin via DUB activity. In colorectal cancer, USP10 substantially represses cancer growth mainly through physical binding compensation and phase separation promotion and correlates with Wnt/β-catenin magnitude clinically. Collectively, we discovered USP10 functioning in multiple biological processes against β-catenin and unearthed a novel enzyme-dependent and -independent “dual-regulating” mechanism by which USP10 utilizes parallelly and context-dependently. USP10 inhibitor was suggested in treating certain Wnt-related diseases.

From providing funds for the global fight against infectious diseases, to actively participating in global health security actions, to strengthening mutual cooperation in the field of health, and providing medical treatment, training and scholarships to countries in need, China's foreign aid on global poverty alleviation is increasingly diversified and expanding in scale. Indeed, China is playing an increasingly important leading role in the global health agenda. It is worth mentioning that over the years, artemisinin compound have saved millions of lives all over the world, especially in poverty-stricken areas. China's work mode of malaria elimination has also been written into WHO's technical documents and recommended to other countries. Since 2007, Chinese medical staff has carried out the Artemisinin Compound Malaria Control Project in Comoros, bringing Chinese prevention and treatment programs to the local area. By 2014, Comoros had achieved zero deaths from malaria, and the number of cases had dropped by 98%. Now, this program is also extended to Togo, another African country. This article preliminarily summarizes the malaria profile in Togo and introduces China-Togo Cooperative Artemisinin Malaria Control Demonstration Project to provide a reference for better anti-malaria assistance in Togo, and also shows one of the substantive actions of China's participation in global health governance, which contributes Chinese wisdom and offers Chinese solutions to global poverty alleviation.

In this work, we successfully constructed a label-free electrochemiluminescence (ECL) immunosensor for the detection of breast cancer marker antigen (CA15-3). In particular, 3,4,9,10-perylenetetracarboxylic acid (PTCA) is cleverly attached to the surface of silica spheres as a luminophore (NH

In this paper, we propose a conservative semi-Lagrangian finite difference (SLFD) weighted essentially non-oscillatory (WENO) scheme, based on Runge-Kutta exponential integrator (RKEI) method, to solve one-dimensional scalar nonlinear hyperbolic equations. Conservative semi-Lagrangian schemes, under the finite difference framework, usually are designed only for linear or quasilinear conservative hyperbolic equations. Here we combine a conservative SLFD scheme developed in [ 21 ], with a high order RKEI method [ 7 ], to design conservative SLFD schemes, which can be applied to nonlinear hyperbolic equations. Our new approach will enjoy several good properties as the scheme for the linear or quasilinear case, such as, conservation, high order and large time steps. The new ingredient is that it can be applied to nonlinear hyperbolic equations, e.g., the Burgers' equation. Numerical tests will be performed to illustrate the effectiveness of our proposed schemes.

Malaria significantly rebounded in 2018 in the Comoros; this created an urgent need to conduct clinical trials to investigate the effectiveness of artemisinin and its derivatives.An open-label, non-randomised controlled trial of artemisinin-piperaquine (AP) and artemether-lumefantrine (AL) was conducted in Grande Comore island from June 2019 to January 2020. A total of 238 uncomplicated falciparum malaria cases were enrolled and divided 1:1 into two treatments. The primary endpoint was the 42-day adequate clinical and parasitological responses (ACPR). Secondary endpoints were parasitaemia and fever clearance at day 3, gametocytes and tolerability.The 42-day ACPR before and after PCR correction were 91.43% (95% CI 83.93-95.76%) and 98.06% (95% CI 92.48-99.66%) for AP treatment, respectively, and 96.00% (95% CI 88.17-98.14%) and 98.97% (95% CI 93.58-99.95%) for AL treatment, respectively. Complete clearance of the parasitaemia and fever for both groups was detected on day 3. Gametocytes disappeared on day 21 in the AP group and on day 2 in AL group. Specifically, the adverse reactions were mild in both groups.It was found that AP and AL maintained their high efficacy and tolerance in the Comoros. Nonetheless, asymptomatic malaria infections bring new challenges to malaria control.

Frizzled (Fzd) proteins are Wnt receptors and play essential roles in development, homeostasis, and oncogenesis. How Wnt/Fzd signaling is coupled to physiological regulation remains unknown. Cholesterol is reported as a signaling molecule regulating morphogen such as Hedgehog signaling. Despite the elusiveness of the in-depth mechanism, it is well-established that pancreatic cancer specially requires abnormal cholesterol metabolism levels for growth. In this study, it is unexpectedly found that among ten Fzds, Fzd5 has a unique capacity to bind cholesterol specifically through its conserved extracellular linker region. Cholesterol-binding enables Fzd5 palmitoylation, which is indispensable for receptor maturation and trafficking to the plasma membrane. In Wnt-addicted pancreatic ductal adenocarcinoma (PDAC), cholesterol stimulates tumor growth via Fzd5-mediated Wnt/β-catenin signaling. A natural oxysterol, 25-hydroxylsterol competes with cholesterol and inhibits Fzd5 maturation and Wnt signaling, thereby alleviating PDAC growth. This cholesterol-receptor interaction and ensuing receptor lipidation uncover a novel mechanism by which Fzd5 acts as a cholesterol sensor and pivotal connection coupling lipid metabolism to morphogen signaling. These findings further suggest that cholesterol-targeting may provide new therapeutic opportunities for treating Wnt-dependent cancers.

Background: Mass drug administration with artemisinin-piperaquine (AP-MDA) is being considered for elimination of residual foci of malaria in Democratic Republic of São Tomé and Principe.Methods: Three monthly rounds of AP-MDA were implemented from July to October 2019. Four zones were selected. A and B were selected as a study site and a control site, respectively. C and D were located within 1.5 and 1.5 km away from the study site, respectively. Parasite prevalence, malaria incidence, and the proportion of the Plasmodium falciparum malaria cases were evaluated.Results: After 3 monthly rounds of AP-MDA, the parasite prevalence and the gametocyte carriage rate of P. falciparum in zone A decreased from 28.29(‰) to 0 and 4.99(‰) to 0, respectively. Compared to zone B, the relative risk for the population with Plasmodium falciparum malaria in zone A was lower (RR = 0.458, 95% CI: 0.146–1.437). Malaria incidence fell from 290.49(‰) (the same period of the previous year) to 15.27(‰) (from the 29th week in 2019 to the 14th week in 2020), a decrease of 94.74% in zone A, and from 31.74 to 5.46(‰), a decline of 82.80% in zone B. Compared to the data of the same period the previous year, the cumulative number of P. falciparum malaria cases were lower, decreasing from 165 to 10 in zone A and from 17 to 4 in zone B. The proportion of the P. falciparum malaria cases on the total malaria cases of the country decreased of 90.16% in zone A and 71.34% in zone C.Conclusion: AP-MDA greatly curbed malaria transmission by reducing malaria incidence in the study site and simultaneously creating a knock-on effect of malaria control within 1.5 km of the study site and within the limited time interval of 38 weeks.

Procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) is a collagen-related lysyl hydroxylase and its prognostic value in glioma patients was verified. However, its biological function in glioma has yet to be fully investigated. The PLOD1 mRNA status and clinical significance in gliomas were assessed via the GEPIA database. Overexpression or targeted depletion of PLOD1 was carried out in the human glioma cell line U87 and verified by western blotting. CCK8 and colony formation assays were implemented to examine the impact of PLOD1 on the proliferative and colony-forming phenotypes of U87 cells. Luciferase reporter assays and HSF1-specific pharmacologic inhibitors (KRIBB11) were employed to determine the regulatory relationship between PLOD1 and heat shock factor 1 (HSF1). High expression of PLOD1 was observed in tissue samples of glioblastoma multiforme (GBM) and brain lower-grade glioma (LGG). GEPIA overall survival further demonstrated that both GBM and LGG patients with high PLOD1 displayed worse clinical outcomes compared with those with low PLOD1. Overexpression and targeted depletion of PLOD1 enhanced and suppressed U87 cell proliferation and colony formation, respectively. Luciferase reporter assays showed that PLOD1 significantly enhanced the transcriptional activity of HSF1 in HEK293T cells. PLOD1 deficiency in U87 cells inhibited HSF1-induced survivin accumulation, whereas KRIBB11 also blocked the PLOD1-overexpressing induced survivin expression. An inhibitor of HSF1 signaling events abolished the increased clonogenic potential caused by PLOD1 overexpression in U87 cells. High expression of PLOD1 can increase the proliferation and colony formation of U87 cells by activating the HSF1 signaling pathway. This study suggested PLOD1/HSF1 as an effective therapeutic target for gliomas.

BACKGROUND: Mass drug administration (MDA), with or without low-dose primaquine (PMQ(LD)), is being considered for malaria elimination programs. The potential of PMQ(LD) to block malaria transmission by mosquitoes must be balanced against liabilities of its use. METHODS: Artemisinin–piperaquine (AP), with or without PMQ(LD), was administered in 3 monthly rounds across Anjouan Island, Union of Comoros. Plasmodium falciparum malaria rates, mortality, parasitemias, adverse events, and PfK13 Kelch-propeller gene polymorphisms were evaluated. RESULTS: Coverage of 85 to 93% of the Anjouan population was achieved with AP plus PMQ(LD) (AP+PMQ(LD)) in 2 districts (population 97164) and with AP alone in 5 districts (224471). Between the months of April–September in both 2012 and 2013, average monthly malaria hospital rates per 100000 people fell from 310.8 to 2.06 in the AP+PMQ(LD) population (ratio 2.06/310.8 = 0.66%; 95% CI: 0.02%, 3.62%; P = .00007) and from 412.1 to 2.60 in the AP population (ratio 0.63%; 95% CI: 0.11%, 1.93%; P < .00001). Effectiveness of AP+PMQ(LD) was 0.9908 (95% CI: 0.9053, 0.9991), while effectiveness of AP alone was 0.9913 (95% CI: 0.9657, 0.9978). Both regimens were well tolerated, without severe adverse events. Analysis of 52 malaria samples after MDA showed no evidence for selection of PfK13 Kelch-propeller mutations. CONCLUSIONS: Steep reductions of malaria cases were achieved by 3 monthly rounds of either AP+PMQ(LD) or AP alone, suggesting potential for highly successful MDA without PMQ(LD) in epidemiological settings such as those on Anjouan. A major challenge is to sustain and expand the public health benefits of malaria reductions by MDA.

Background Malaria is still one of the serious public health problems in Grande Comore Island, although the number of annual cases has been greatly reduced in recent years. A better understanding of malaria parasite population diversity and transmission dynamics is critical for assessing the effectiveness of malaria control measures. The objective of this study is to investigate temporal changes in genetic diversity of Plasmodium falciparum populations and multiplicity of infection (MOI) in Grande Comore 10 years after introduction of ACT. Methods A total of 232 P. falciparum clinical isolates were collected from the Grande Comore Island during two sampling periods (118 for 2006‒2007 group, and 114 for 2013‒2016 group). Parasite isolates were characterized for genetic diversity and complexity of infection by genotyping polymorphic regions in merozoite surface protein gene 1 (msp-1), msp-2, and msp-3 using nested PCR and DNA sequencing. Results Three msp-1 alleles (K1, MAD20, and RO33), two msp-2 alleles (FC27 and 3D7), and two msp-3 alleles (K1 and 3D7) were detected in parasites of both sampling periods. The RO33 allele of msp-1 (84.8%), 3D7 allele of msp-2 (90.8%), and K1 allele of msp-3 (66.7%) were the predominant allelic types in isolates from 2006–2007 group. In contrast, the RO33 allele of msp-1 (63.4%), FC27 allele of msp-2 (91.1%), and 3D7 allele of msp-3 (53.5%) were the most prevalent among isolates from the 2013–2016 group. Compared with the 2006‒2007 group, polyclonal infection rates of msp-1 (from 76.7 to 29.1%, P

Background Plasmodium falciparum malaria is a significant public health problem in Comoros, and artemisinin combination therapy (ACT) remains the first choice for treating acute uncomplicated P. falciparum. The emergence and spread of artemisinin-resistant P. falciparum in Southeast Asia, associated with mutations in K13-propeller gene, poses a potential threat to ACT efficacy. Detection of mutations in the P. falciparum K13-propeller gene may provide the first-hand information on changes in parasite susceptibility to artemisinin. The objective of this study is to determinate the prevalence of mutant K13-propeller gene among the P. falciparum isolates collected from Grande Comore Island, Union of Comoros, where ACT has been in use since 2004. Methods A total of 207 P. falciparum clinical isolates were collected from the island during March 2006 and October 2007 (n = 118) and March 2013 and December 2014 (n = 89). All isolates were analysed for single nucleotide polymorphisms (SNPs) and haplotypes in the K13-propeller gene using nested PCR and DNA sequencing. Results Only three 2006–2007 samples carried SNPs in the K13-propeller gene, one having a synonymous (G538G) and the other having two non-synonymous (S477Y and D584E) substitutions leading to two mutated haplotypes (2.2 %, 2/95). Three synonymous mutations (R471R, Y500Y, and G538G) (5.9 %, 5/85) and 7 non-synonymous substitutions (21.2 %, 18/85) with nine mutated haplotypes (18.8 %, 16/85) were found in isolates from 2013 to 2014. However, none of the polymorphisms associated with artemisinin-resistance in Southeast Asia was detected from any of the parasites examined. Conclusion This study showed increased K13-propeller gene diversity among P. falciparum populations on the Island over the course of 8 years (2006–2014). Nevertheless, none of the polymorphisms known to be associated with artemisinin resistance in Asia was detected in the parasite populations examined. Our data suggest that P. falciparum populations in Grande Comore are still effectively susceptible to artemisinin. Our results provide insights into P. falciparum populations regarding mutations in the gene associated with artemisinin resistance and will be useful for developing and updating anti-malarial guidance in Comoros.

Background In Comoros, the widespread of chloroquine (CQ)-resistant Plasmodium falciparum populations was a major obstacle to malaria control, which led to the official withdrawal of CQ in 2004. Continuous monitoring of CQ-resistant markers of the P. falciparum CQ resistant transporter (pfcrt) and the P. falciparum multiple drug resistance 1 (pfmdr-1) is necessary inder to obtain first-hand information on CQ susceptibility of parasite populations in the field. The objective of this study is to assess the prevalence and evolution of CQ-resistance in the P. falciparum populations on the Comoros’ Grande Comore island after withdrawal of CQ. Methods A total of 207 P. falciparum clinical isolates were collected from the island, including 118 samples from 2006 to 2007 and 89 samples from 2013 to 2014. Nucleotide substitutions in the pfcrt and pfmdr-1 genes linked to CQ response in parasite isolates were assessed using nested PCR and DNA sequencing. Results From the pfcrt gene segment sequenced, we detected C72S, M74I, N75E, and K76T substitutions in the parasite isolates collected from both 2006–2007 to 2013–2014 periods. Significant decline of pfcrt resistant alleles at C72S (42.6 to 6.9 %), M74I (39.1 to 14.9 %), N75E (63.5 to 18.3 %), and K76T (72.2 to 19.5 %) from 2006–2007 to 2013–2014 were observed, and the frequency of pfcrt wild type allele was significantly increased from 19.1 % in 2006–2007 to 75.8 % in 2013–2014. Sequence analysis of pfmdr-1 also detected point mutations at codons N86Y, Y184F, and D1246Y, but not S1034C and N1042D, in the isolates collected from both examined periods. An increasing trend in the prevalence of the pfmdr-1 wild type allele (NYD, 4.3 % in 2006–2007; and 28.7 % in 2013–2014), and a decreasing trend for pfmdr-1 N86Y mutation (87.0 % in 2006–2007; and 40.2 % in 2013–2014) were observed in our samples. Conclusions The present data indicate that the prevalence and patterns of mutant pfcrt and pfmdr-1 dramatically decreased in the Grande Comore isolates from 2006 to 2014, suggesting that the CQ-sensitive P. falciparum strains have returned after the withdrawal of CQ. The data also suggests that the parasites with wild type pfcrt/pfdmr-1 genes may have growth and/or transmission advantages over the mutant parasites. The information obtained from this study will be useful for developing and updating anti-malarial treatment policy in Grande Comore island.