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Methods HT29 and SW480 cell lines were fostered in media containing L-OHP or 5-Fu to establish drug-resistant strains. Injected subcutaneously HT29 and SW480 drug-resistant cells into the ventral of nude mice at a dose of 5 × 106 to establish CRC drug-resistant animal models. CCK-8, Western blot, flow cytometry, Transwell and kit detection were used to detect the regulation mechanism of energy metabolism reprogramming in drug-resistant CRC cells. Results: Compared with non-resistant strains, L-OHP/5-fu resistant strains had stronger ability of metabolic reprogramming. Functionally, SHP099 can restrain the metabolic reprogramming of L-OHP/5-fu resistant strains, and then restrain the cell proliferation, cloning, migration and tumor spheroid formation of L-OHP/5-fu resistant strains. Downstream mechanism studies have shown that SHP099 interferes with the metabolic reprogramming of L-OHP/5-fu drug-resistant strains by suppressing PI3K/AKT pathway, thereby restraining the malignant biological behavior of L-OHP/5-fu drug-resistant strains and alleviating CRC. Conclusion: The combination of SHP099 can restrain the malignant biological behavior of L-OHP/5-fu resistant CRC cells and alleviate the progression of CRC by interfering with the reprogramming of energy metabolism.

Calciphylaxis is a rare disease characterized histologically by microvessel calcification and microthrombosis, with high mortality and no proven therapy. Here, we reported a severe uremic calciphylaxis patient with progressive skin ischemia, large areas of painful malodorous ulcers, and mummified legs. Because of the worsening symptoms and signs refractory to conventional therapies, treatment with human amnion-derived mesenchymal stem cells (hAMSCs) was approved. Preclinical release inspections of hAMSCs, efficacy, and safety assessment, including cytokine secretory ability, immunocompetence, tumorigenicity, and genetics analysis in vitro, were introduced. We further performed acute and long-term hAMSC toxicity evaluations in C57BL/6 mice and rats, abnormal immune response tests in C57BL/6 mice, and tumorigenicity tests in neonatal Balbc-nu nude mice. After the preclinical research, the patient was treated with hAMSCs by intravenous and local intramuscular injection and external supernatant application to the ulcers. When followed up to 15 months, the blood-based markers of bone and mineral metabolism improved, with skin soft tissue regeneration and a more favorable profile of peripheral blood mononuclear cells. Skin biopsy after 1-month treatment showed vascular regeneration with mature noncalcified vessels within the dermis, and 20 months later, the re-epithelialization restored the integrity of the damaged site. No infusion or local treatment-related adverse events occurred. Thus, this novel long-term intravenous combined with local treatment with hAMSCs warrants further investigation as a potential regenerative treatment for uremic calciphylaxis due to effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, anti-inflammatory and immune modulation, multidifferentiation, re-epithelialization, and restoration of integrity.

Coronary artery fistula (CAF) is a rare malformation and is seldom reported during pregnancy. Right coronary artery fistula commonly drains into the right ventricle, right atrium, or pulmonary artery. We describe here a rare case of fetal CAF draining into the left ventricle using cross-sectional and color Doppler echocardiography. We also summarized our experience in the diagnosis of this uncommon malformation, in which tracing the origin, course, and outlet of the abnormal intra-cardiac flow played a key role.

Calciphylaxis is a rare disease characterized histologically by microvessel calcification and microthrombosis, with high mortality and no proven therapy. We reported a severe uremic calciphylaxis patient with progressive skin ischemia, large areas of painful malodorous ulcers and mummified legs. Because of her rapid progression and refractory to conventional therapy, human amnion-derived mesenchymal stem cells (hAMSCs) treatment was approved. Establishment and release inspection of hAMSCs, efficacy and safety assessment including cytokines secretory ability, immunocompetence, tumorigenicity and genetics analysisin vitrowere introduced. We further performed acute and long-term hAMSC toxity evaluations in C57BL/6 mice/rats, abnormal immune response tests in C57BL/6 mice and tumorigenic tests in the neonatal NU nude mice. After pre-clinical research, she was treated by hAMSCs with intravenous and local intramuscular injection and external supernatants application to her ulcers. When followed up to 15 months, her blood-based markers of bone and mineral metabolism were improved, with regeneration of skin soft tissue and a more favorable profile of peripheral blood mononuclear cells. Skin biopsy after 1 month treatment showed vascular regeneration with mature non-calcified vessels within dermis and 20 months later re-epithelialization restored the integrity of damaged site. No infusion or local treatment related adverse events occurred. To the best of our knowledge, this is the first evidence for the clinical use of hAMSCs. These findings suggest hAMSCs warrant further investigation as a potential regenerative treatment for uremic calciphylaxis with effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, anti-inflammatory and immune modulation, multi-differentiation, re-epithelialization and restorage of integrity.

Lakes are important natural resources closely related to human survival and development. Based on PIE cloud computing platform, the study uses Landsat images and the empirical normalized water body index (ENDWI) to extract water body information of the large lakes in Sichuan province from 2000 to 2020 in the drought and rainy seasons, respectively, and uses the Mann–Kendall test to obtain the long-term trends of their area and climate. On this basis, the evolution of the lakes and their correlation with climate and human activities are analyzed. The results show that (1) In the past 20 years, the area of Lugu Lake, Qionghai Lake, and Luban Reservoir represent a decreasing trend, with Lugu Lake being the most affected. The area of Ma Lake, Three Forks Lake, and Shengzhong Reservoir increased, with the area of Shengzhong Reservoir increasing significantly; (2) During the drought season, all six lakes showed a decreasing trend in precipitation, with the most apparent decreasing trend for Lugu Lake (Slope = −0.8). Only Lugu Lake showed a decreasing trend in precipitation (Slope = −0.15) during the rainy season. The precipitation of Ma Lake, Three Forks Lake, Luban Reservoir and Shengzhong Reservoir showed a significant increasing trend (Slope value was greater than 1.96); (3) The temperatures of the remaining lakes all decreased in the drought season and increased in the rainy season, except that the temperature of Shengzhong Reservoir decreases throughout the year; (4) The area change of plain lakes is greatly affected by human activities, but the area of plateau lakes is are more impacted by climate. Our study improved the accuracy of long-term water body change monitoring with PIE-Engine Studio. Besides, the findings would provide reference for the implementation of sustainable water resources management in Sichuan Province.

Background Age-related diminished ovarian reserve (AR-DOR) reduced the quality of oocytes, resulting in decreased female fertility. Aging is tightly related to abnormal distribution and function of mitochondria, while mitophagy is a major process to maintain normal quality and quantity of mitochondria in cells, especially in oocytes which containing a large number of mitochondria to meet the demand of energy production during oocyte maturation and subsequent embryonic development. Ampk/FoxO3a signaling is crucial in the regulation of mitophagy. It is reported mesenchymal stem cells (MSCs) can improve ovarian function. Here we aim to explore if human amnion-derived mesenchymal stem cells (hAMSCs) are effective in improving ovarian function in AR-DOR mice and whether Ampk/FoxO3a signaling is involved. Methods The AR-DOR model mice were established by 32-week-old mice with 3–8 litters, significantly low serum sex hormone levels and follicle counts. The old mice were divided into 5 treatment groups: normal saline (NS, control), 1% human serum albumin (HSA, resolver), low dose (LD, 5.0 × 106cells/kg), middle dose (MD, 7.5 × 106cells/kg), and high dose (HD, 10.0 × 106cells/kg). The prepared hAMSCs were injected through tail vein. Serum sex hormone level, follicle counts, fertilization rate, gestation rate, little size, apoptosis of granulosa and stromal cells, expression level of Sod2, Ampk, and ratio of phosphorylated FoxO3a to total FoxO3a in ovaries were examined. Results Our results show that after hAMSC transplantation, the ovarian function in AR-DOR mice was significantly improved, meanwhile the apoptosis of granulosa and stromal cells in the ovaries was significantly repressed, the expression level of Ampk and the ratio of phosphorylated FoxO3a to total FoxO3a both were significantly increased, meanwhile increased Sod2 expression was also observed. Conclusion Our results demonstrate hAMSC transplantation via tail-injection can improve ovarian function of AR-DOR mice through Ampk/FoxO3a signaling pathway.

Applications of Earth-observational remote sensing are rapidly increasing over urban areas. The latest regime shift from conventional urban development to smart-city development has triggered a rise in smart innovative technologies to complement spatial and temporal information in new urban design models. Remote sensing-based Earth-observations provide critical information to close the gaps between real and virtual models of urban developments. Remote sensing, itself, has rapidly evolved since the launch of the first Earth-observation satellite, Landsat, in 1972. Technological advancements over the years have gradually improved the ground resolution of satellite images, from 80 m in the 1970s to 0.3 m in the 2020s. Apart from the ground resolution, improvements have been made in many other aspects of satellite remote sensing. Also, the method and techniques of information extraction have advanced. However, to understand the latest developments and scope of information extraction, it is important to understand background information and major techniques of image processing. This chapter briefly describes the history of optical remote sensing, the basic operation of satellite image processing, advanced methods of object extraction for modern urban designs, various applications of remote sensing in urban or peri-urban settings, and future satellite missions and directions of urban remote sensing.

Landscape ecological risk assessment (LERA) evaluates different types of potential environmental impacts and their cumulative effects, thereby providing policy insights for sustainable regional land-use and ecosystem management. In a departure from existing literature that heavily relies on low-resolution land-use data for LERA at provincial or municipal scales, this study applies high-resolution land-use data to a relatively small research area (county). In addition, this study modifies the evaluation units of LERA from equal-sized grids to watersheds and refines the ecological vulnerability weight on the basis of finer-resolution data. The main findings are summarized as follows: (1) In 2011&ndash, 2013, nearly 866 ha of land use in Xiapu County changed, moreover, the construction land, which was mainly concentrated in Songgang Street and Xinan Town, increased the most (340 ha). (2) Landscape ecological risk (LER) was roughly maintained, and areas of high ecological risk were mainly concentrated along the coast. (3) The spatial distribution of LER maintained a relatively aggregated pattern, with no trend toward more aggregated or more dispersed change. This study further discusses the relationship between local LER and land-use change and how to balance global and local LER in planning practices.

BACKGROUND: Falcipain-2a ([FP2a] PF3D7_1115700) is a Plasmodium falciparum cysteine protease and hemoglobinase. Functional FP2a is required for potent activity of artemisinin, and in vitro selection for artemisinin resistance selected for an FP2a nonsense mutation. METHODS: To investigate associations between FP2a polymorphisms and artemisinin resistance and to characterize the diversity of the enzyme in parasites from the China-Myanmar border, we sequenced the full-length FP2a gene in 140 P falciparum isolates collected during 2004–2011. RESULTS: The isolates were grouped into 8 different haplotype groups. Haplotype group I appeared in samples obtained after 2008, coinciding with implementation of artemisinin-based combination therapy in this region. In functional studies, compared with wild-type parasites, the FP2a haplotypes demonstrated increased ring survival, and all haplotype groups exhibited significantly reduced FP2a activity, with group I showing the slowest protease kinetics and reduced parasite fitness. CONCLUSIONS: These results suggest that altered hemoglobin digestion due to FP2a mutations may contribute to artemisinin resistance.

Background: Adoptive immunotherapy (AIT) has been adopted as an adjuvant treatment for hepatocellular carcinoma (HCC) patients after curative therapy. However, the outcomes of AIT remain controversial. Purpose: The purpose of this study is to analyze the safety and efficacy of AIT with the recurrence rate and mortality. Materials and Methods: We identified eight randomized controlled trials (RCTs) that adopted AIT to HCC after curative treatments. A meta-analysis was carried out to assess the recurrence rate and mortality. Results: Eight RCTs with 964 patients were included in the study. The overall analysis showed that AIT treatment can not only decrease the 1-year (risk ratio [RR] =0.59, 95% confidence interval [95% CI] = 0.48–0.72, P < 0.00001), 2-year (RR = 0.69, 95% CI = 0.60–0.79, P < 0.00001), and 3-year (RR = 0.82, 95% CI = 0.74–091, P = 0.0001) recurrence, but also decrease the 1-year (RR = 0.43, 95% CI = 0.30–0.62, P = 0.00001), 2-year (RR = 0.56, 95% CI = 0.46–0.74, P < 0.00001), and 3-year (RR = 0.85, 95% CI = 0.73–0.99, P = 0.03) mortality. The results also indicate that the group of lymphokine-activated killer (LAK) cells showed lower pooled RR values compared to the group of cytokine-induced killer cells among every subgroups. However, the AIT treatment failed to affect the 5-year recurrence rate and mortality (P > 0.05). Conclusions: This review provides available evidences that AIT, especially the treatment of LAK, can be used to decrease the early recurrence and mortality of postoperative HCC but may not the long term.

Background Prenatal diagnosis of fetal total anomalous pulmonary vein connection (TAPVC) remains challenging for most screening sonographers. The purpose of this study was to evaluate the use of four-dimensional echocardiography with high-definition flow imaging and spatiotemporal image correlation (4D-HDFI) in identifying pulmonary veins in normal and TAPVC fetuses. Material & Methods We retrospectively reviewed and performed 4D-HDFI in 204 normal and 12 fetuses with confirmed diagnosis of TAPVC. Cardiac volumes were available for postanalysis to obtain 4D-rendered images of the pulmonary veins. For the normal fetuses, two other traditional modalities including color Doppler and HDFI were used to detect the number of pulmonary veins and comparisons were made between each of these traditional methods and 4D-HDFI. Results For conventional echocardiography, HDFI modality was superior to color Doppler in detecting more pulmonary veins in normal fetuses throughout the gestational period. 4D-HDFI was the best method during the second trimester of pregnancy in identifying normal fetal pulmonary veins. 4D-HDFI images vividly depicted the figure, course, and drainage of pulmonary veins in both normal and TAPVC fetuses. Conclusion HDFI and the advanced 4D-HDFI technique could facilitate identification of the anatomical features of pulmonary veins in both normal and TAPVC fetuses; 4D-HDFI therefore provides additional and more precise information than conventional echocardiography techniques.

Background The malaria elimination plan of the Greater Mekong Subregion (GMS) is jeopardized by the increasing number of Plasmodium vivax infections and emergence of parasite strains with reduced susceptibility to the frontline drug treatment chloroquine/primaquine. This study aimed to determine the evolution of the P. vivax multidrug resistance 1 (Pvmdr1) gene in P. vivax parasites isolated from the China–Myanmar border area during the major phase of elimination. Methods Clinical isolates were collected from 275 P. vivax patients in 2008, 2012–2013 and 2015 in the China–Myanmar border area and from 55 patients in central China. Comparison was made with parasites from three border regions of Thailand. Results Overall, genetic diversity of the Pvmdr1 was relatively high in all border regions, and over the seven years in the China–Myanmar border, though slight temporal fluctuation was observed. Single nucleotide polymorphisms previously implicated in reduced chloroquine sensitivity were detected. In particular, M908L approached fixation in the China–Myanmar border area. The Y976F mutation sharply decreased from 18.5% in 2008 to 1.5% in 2012–2013 and disappeared in 2015, whereas F1076L steadily increased from 33.3% in 2008 to 77.8% in 2015. While neutrality tests suggested the action of purifying selection on the pvmdr1 gene, several likelihood-based algorithms detected positive as well as purifying selections operating on specific amino acids including M908L, T958M and F1076L. Fixation and selection of the nonsynonymous mutations are differently distributed across the three border regions and central China. Comparison with the global P. vivax populations clearly indicated clustering of haplotypes according to geographic locations. It is noteworthy that the temperate-zone parasites from central China were completely separated from the parasites from other parts of the GMS. Conclusions This study showed that P. vivax populations in the China–Myanmar border has experienced major changes in the Pvmdr1 residues proposed to be associated with chloroquine resistance, suggesting that drug selection may play an important role in the evolution of this gene in the parasite populations.

Background Prenatal diagnosis of cardiac valve anomalies challenged most screening sonographers. The purpose of the study was to evaluate the use of four-dimensional echocardiography with spatiotemporal image correlation (4DSTIC) in detecting normal and abnormal fetal cardiac valves. Methods Forty-three cases of confirmed cardiac valve anomalies identified by two-dimensional echocardiography (2DE) were retrospectively reviewed in this study. Additional 121 confirmed normal fetuses were included as controls. Four-dimensional volumes were acquired from each fetus using a transverse sweep. Four-dimensional rendered images were retrieved from the volumes for each of the cardiac valves for the normal fetuses and for the intended valves for fetuses with valve malformations. Results The visualization rates of cardiac valves retrieved from 4D volumes in the normal fetuses ranged from 72.5% to 97.5% before 33 gestational weeks and from 46.3% to 80.5% in late pregnancy. Furthermore, 4D rendered images were successfully obtained in 38 of 43 (88.4%) fetuses with cardiac valve lesions. Conclusions The 4D images and cine loops displayed the valves anatomy vividly in both normal and abnormal fetuses, including some subtle malformations which were not identified by traditional 2DE. The standardized protocol we propose herein was important in obtaining the 4D images from the volumes. The 4D modality allows a better visualization of fetal cardiac valves and should be considered a valuable addition to traditional 2DE imaging.

Transmission-blocking vaccines (TBVs) interrupting malaria transmission are an integrated tool for malaria eradication. We characterized a sexual-stage-specific gene (PBANKA_060330) from Plasmodium berghei and studied its potential for use as a TBV. This gene, referred to as pbg37, encodes a protein of 37 kDa with a signal peptide and multiple transmembrane domains and is preferentially expressed in gametocytes. A recombinant Pbg37 (rPbg37) protein targeting the N-terminal 63 amino acids (amino acids 26 to 88) expressed in bacteria elicited strong antibody responses in mice. Western blotting demonstrated Pbg37 expression in gametocytes, zygotes, and, to a lesser extent, ookinetes and its predominant association with the membranes of gametocytes. Indirect immunofluorescence assay showed an abundant surface localization of Pbg37 on gametes and zygotes but reduced amounts on retorts and ookinetes. Knockout of pbg37 (Δpbg37) led to a considerable reduction in gametocytemia, which translated into a ~92.1% decrease in the oocyst number in mosquitoes. Deletion of pbg37 had a more substantial influence on the development and maturation of microgametocytes. As a result, the Δpbg37 lines exhibited a higher female/male gametocyte ratio, fewer mature male gametocytes, and defects in the exflagellation of mature microgametocytes. To test the transmission-blocking potential of Pbg37, an in vitro ookinete assay showed that the major inhibitory effects of anti-Pbg37 antiserum were on the exflagellation and fertilization processes. Direct feeding of mosquitoes on mice immunized with rPbg37 or a control protein showed that rPbg37-immunized and P. berghei-infected mice had a significant reduction (49.1%) in oocyst density compared to the controls. The conservation of this gene in Plasmodium warrants further investigations in human malaria parasites.

Obtaining an accurate diagnosis of fetal aortic arch anomalies is often difficult with traditional two-dimensional (2D) sonography. Thus, the aim of this study was to assess the value of three-dimensional (3D) sonography with spatiotemporal image correlation for diagnosing fetal aortic arch anomalies using a novel algorithm for 3D volume analysis.Two-dimensional and 3D echocardiographic image data from 300 normal fetuses and 30 fetuses with aortic arch anomalies were retrospectively reviewed. Grayscale and high-definition flow imaging data were available for 2D echocardiography. Three-dimensional volumes were acquired in parasagittal views with high-definition flow imaging information. Volume postprocessing was performed using a novel algorithm to obtain 3D tomographic ultrasound imaging slices and color-rendered images. Detection of aortic arch positions, aberrant brachiocephalic patterns, and aortic arch anomalies was compared for 2D and 3D modalities. Postnatal echocardiography was used as the truth standard in assessing aortic anatomy.In total, four cases of double aortic arch, 21 cases of right aortic arch, one case of retroesophageal aortic arch, and four cases of left aortic arch with aberrant right subclavian arteries were included. Inter- and intraobserver agreement were excellent for 2D and 3D modalities. The 3D modality offered better sensitivity and accuracy compared with 2D imaging for the detection of brachiocephalic anomalies (P .01) and arch anomalies (P .01) but comparable sensitivity for arch position. There was no difference in specificity for both modalities.The proposed novel algorithm for volume postprocessing ensures that 3D reconstructed images are obtained with high repeatability. The addition of 3D spatiotemporal image correlation to fetal echocardiography may offer a more accurate diagnosis for arch anomalies.

Reported here is a simple and rapid static headspace gas chromatography (SHS-GC) method for the determination of trace solvents including ethanol, isopropanol, n-butanol, 1,4-dioxane, tetrahydrofuran, acetonitrile, methanol and acetone which commonly used in drug production process. Natural deep eutectic solvents (NADESs) are firstly used as the matrix medium for this method, which provided high sensitivity for residual solvents detection. With the optimized method, validation experiments were performed and the data showed excellent linearity for all the solvents (R2 ≥ 0.999, n = 7). The limits of detection (LOD) for ethanol, isopropanol, n-butanol, 1,4-dioxane, tetrahydrofuran, acetonitrile, methanol and acetone are 0.09, 0.08, 0.07, 0.11, 0.06, 0.10, 0.12 and 0.08 μg g−1, respectively. Accuracy was checked by a recovery experiment at three different levels, and the recoveries of the tested solvents were ranged from 94.3% to 105.4%. The relative standard deviation (RSD) of each solvent for intra- and inter-day precision is in the range of 0.85 to 3.65 and 1.51 to 4.53, respectively. The developed approach can be readily used for determination of the residual solvents in six active pharmaceutical ingredients including pramipexole dihydrochloride, rivaroxaban, lisinopril, ramipril, imatinib mesylate and sitagliptin.

Aims: Foramen ovale (FO) valve with a shape or motion abnormality is frequently detected during routine obstetric ultrasonic examinations. However, the hemodynamics mechanism of this entity remains unclear. The purpose of the study is to determine the relevance of interatrial communication restriction and resultant morphological modifications.Materials and methods: We reviewed the echocardiographic records of fetuses with isolated abnormal FO valve evaluated between January of 2010 and december of 2016. The size (DFO) of the FO orifice, opening angle (α) of the FO valve, and dimensions of cardiac chambers, FO channel outlet (DOUT) and inferior vena cava (DIVC) were measured. We evaluated their (DFO, DOUT, α) relationships to the diameters of RA and DIVC. Five hundred and seventy normal fetuses were selected to establish the normal range of the DOUT/DIVC ratio so as to provide a criterion for restriction.Results: An abnormal FO valve was identified in 89 fetuses without congenital heart disease, with restriction noted in 62 fetuses (45 fetuses with RA dilatation, 12 fetuses with RA and RV dilatation, and 5 fetuses with no RA dilatation). There were no significant correlations between RA/LA and DFO/DIVC, RA/ LA and α. RA/LA was negatively correlated with DOUT/DIVC (R2=0.97, p

The impact of sludge discharge on membrane fouling during ultrafiltration of surface water was investigated in this study. Discharge sludge and without discharge during UF were compared by measuring the increase of transmembrane pressure (TMP) and the accumulation of foulants with running time was studied. It was found that turbidity and dissolved organic carbon of retentate solution apparently increased as UF proceeded. Three-dimensional excitation/emission matrix fluorescence spectroscopy analyses of raw water and retentate solution demonstrated that UF could lead to the accumulation of humic and protein-like substances. Filtration experiments showed that membrane fouling could be alleviated by discharging the retentate solution after physical cleaning due to the reduced cake layer formation and concentration polarization. In addition, effects of sludge discharge intervals on the TMP and fouling characteristics were further investigated. Results indicated that short SDI would benefit control of both reversible and irreversible fouling. However, frequent discharge of retentate solution may increase the self-use water and decrease the water production rate of the UF system, leading to an expansion of running cost. In general, SDI was a critically important factor for both membrane fouling and water production rate.

Background Artemisinin resistance in Plasmodium falciparum has emerged as a major threat for malaria control and elimination worldwide. Mutations in the Kelch propeller domain of PfK13 are the only known molecular markers for artemisinin resistance in this parasite. Over 100 non-synonymous mutations have been identified in PfK13 from various malaria endemic regions. This study aimed to investigate the genetic diversity of PvK12, the Plasmodium vivax ortholog of PfK13, in parasite populations from Southeast Asia, where artemisinin resistance in P. falciparum has emerged. Methods The PvK12 sequences in 120 P. vivax isolates collected from Thailand (22), Myanmar (32) and China (66) between 2004 and 2008 were obtained and 353 PvK12 sequences from worldwide populations were retrieved for further analysis. Results These PvK12 sequences revealed a very low level of genetic diversity (π = 0.00003) with only three single nucleotide polymorphisms (SNPs). Of these three SNPs, only G581R is nonsynonymous. The synonymous mutation S88S is present in 3% (1/32) of the Myanmar samples, while G704G and G581R are present in 1.5% (1/66) and 3% (2/66) of the samples from China, respectively. None of the mutations observed in the P. vivax samples were associated with artemisinin resistance in P. falciparum. Furthermore, analysis of 473 PvK12 sequences from twelve worldwide P. vivax populations confirmed the very limited polymorphism in this gene and detected only five distinct haplotypes. Conclusions The PvK12 sequences from global P. vivax populations displayed very limited genetic diversity indicating low levels of baseline polymorphisms of PvK12 in these areas. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1583-0) contains supplementary material, which is available to authorized users.

Malaria parasites in different areas where malaria is endemic display different levels of resistance to antimalarial drugs as the result of varied drug use histories. To provide updated knowledge of drug sensitivities during the malaria elimination phase in Southeast Asia, an epicenter of multidrug resistance, we determined in vitro susceptibilities of culture-adapted Plasmodium falciparum isolates from two eastern border regions (Wa and Kachin) of Myanmar to 10 drugs. Despite their close proximity, the Kachin parasites displayed higher 50% inhibitory concentrations than the Wa parasites to chloroquine, piperaquine, naphthoquine, mefloquine, quinine, pyrimethamine, pyronaridine, lumefantrine, and dihydroartemisinin. Genotyping of genes associated with drug resistance also showed significant differences in the prevalence rates of mutant alleles between the two regions. Particularly, major pfdhfr mutations mediating pyrimethamine resistance and the pfdhps A437G mutation had significantly higher frequencies in the Kachin parasites ( P < 0.005). Moreover, when pfdhfr and pfdhps were considered together, the wild-type allele was found only in the Wa samples (22.6%). In addition, the pfmdr1 Y184F mutation reached 38.7% in the Kachin parasites, compared to 9.7% in the Wa parasites, whereas N86Y was only detected in the Wa parasites, at 22.6%. Furthermore, the F446I mutation and all mutations in the propeller domain of the PfK13 gene were significantly more frequent in the Kachin parasites. Collectively, this work demonstrates that even in spatially closely separated regions, parasites can exhibit drastic differences in drug sensitivities and genetic makeups underlying drug resistance, which may reflect regionally different drug histories and genetic drift of these isolated parasite populations.

The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20–25 °C and 10 L/(m2 h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9 ± 1.7%), UV254 (by 27.1 ± 1.7%), and microcystins (expressed as MC-LReq, by 40.8 ± 4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LReq concentration by PAC adsorption.

Background Transmission-blocking vaccines (TBVs) are a promising strategy for malaria control and elimination. However, candidate TBV antigens are currently limited, highlighting the urgency of identifying new antigens for TBV development. Methods Using a combination of bioinformatic analysis and functional studies in the rodent malaria model Plasmodium berghei, we identified a conserved Plasmodium protein PbPH (PBANKA_041720) containing a pleckstrin homology (PH) domain. The expression of PbPH was detected by Western blot and indirect immunofluorescence assay (IFA). The function of PbPH was tested by genetic knockout. The TB activity was confirmed by in vitro ookinete conversion assay and mosquito feeding. Results PbPH was detected in Western blot as highly expressed in sexual stages (gametocytes and ookinetes). IFA revealed localizations of PbPH on the surface of gametes, zygotes, and ookinetes. Deletion of the pbph gene did not affect asexual growth, but significantly reduced the formation of gametocytes, ookinetes, and oocysts, indicating that PbPH protein is required for parasite sexual development. Recombinant PbPH expressed and purified from bacteria elicited strong antibody responses in mice and the antibodies significantly inhibited exflagellation of male gametocytes and formation of ookinetes in a concentration-dependent manner. Mosquito feeding experiments confirmed that mosquitoes fed on mice immunized with PbPH had 13 % reduction in the prevalence of infection and almost 48 % reduction in oocyst density. Conclusions Pbph is a highly conserved Plasmodium gene and is required for parasite sexual development. PbPH protein is expressed on the surface of gametes and ookinetes. Immunization of mice against the recombinant PbPH protein induced strong antibody responses that effectively reduced the formation of male gametes and ookinetes in vitro and blocked transmission of the parasites to mosquitoes. These results highlight PbPH as a potential TBV candidate that is worth future investigations in human malaria parasites. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1459-8) contains supplementary material, which is available to authorized users.

Additional file 4. Multiple sequence alignment of Kelch protein from seven different Plasmodium species. Clustal Omega server was used to align the Kelch proteins from P. falciparum (PF3D7_1343700); P. reichenowi (PRCDC_1342700); P. chabaudi (PCHAS_1361300); P. berghei (PBANKA_1356700); P. yoelii (PY17X_1362400); P. knowlesi (PKNH_1257700); P. cynomolgi (PCYB_122000), P. vivax (PVX_083080). The BTB and the Kelch domains are boxed in red and blue respectively. Cysteine residues are highlighted in green. The dots indicate the break in the sequences. The BTB domains starting from 327 are shown and boxed in red. The Kelch domains are shown in blue box. The hyphens show the gaps in the alignment.

Background The male gamete fertilization factor P48/45 in malaria parasites is a prime transmission-blocking vaccine (TBV) candidate. Efforts to develop antimalarial vaccines are often thwarted by genetic diversity of the target antigens. Here we evaluated the genetic diversity of Pvs48/45 gene in global Plasmodium vivax populations. Methods We determined 200 Pvs48/45 sequences collected from temperate and subtropical parasite populations in China. Population genetic and evolutionary analyses were performed to determine the levels of genetic diversity, potential signature of selection, and population differentiation. Results Analysis of the Pvs48/45 sequences from 200 P. vivax parasites collected in a temperate and a tropical region revealed a low level of genetic diversity (π = 0.0012) with 14 single nucleotide polymorphisms, of which 11 were nonsynonymous. Analysis of 344 Pvs48/45 sequences from nine worldwide P. vivax populations detected a total of 38 haplotypes, of which 13 haplotypes were present only once. Multiple tests for selection confirmed a signature of positive selection on Pvs48/45 with selection skewed to the second cysteine domain. Haplotype network analysis and Wright’s fixation index showed large geographical differentiation with the presence of continent-or region-specific mutations in this gene. Conclusions Pvs48/45 displays low levels of genetic diversity with the presence of region-specific mutations. Some of the mutations may be potential epitope targets based on their positions in the predicted structure, highlighting the need for future evaluation of these mutations in designing Pvs48/45-based TBV. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1232-4) contains supplementary material, which is available to authorized users.

In animal models of experimental cerebral malaria (ECM), neuropathology is associated with an overwhelming inflammatory response and sequestration of leukocytes and parasite-infected RBCs in the brain. In this study, we explored the effect of vitamin D (VD; cholecalciferol) treatment on host immunity and outcome of ECM in C57BL/6 mice during Plasmodium berghei ANKA (PbA) infection. We observed that oral administration of VD both before and after PbA infection completely protected mice from ECM. VD administration significantly dampened the inducible systemic inflammatory responses with reduced circulating cytokines IFN-γ and TNF and decreased expression of these cytokines by the spleen cells. Meanwhile, VD also resulted in decreased expression of the chemokines CXCL9 and CXCL10 and cytoadhesion molecules (ICAM-1, VCAM-1, and CD36) in the brain, leading to reduced accumulation of pathogenic T cells in the brain and ultimately substantial improvement of the blood–brain barriers of PbA-infected mice. In addition, VD inhibited the differentiation, activation, and maturation of splenic dendritic cells. Meanwhile, regulatory T cells and IL-10 expression levels were upregulated upon VD treatment. These data collectively demonstrated the suppressive function of VD on host inflammatory responses, which provides significant survival benefits in the murine ECM model.

Background Malaria and schistosomiasis are endemic and co-exist in the same geographic areas, even co-infecting the same host. Previous studies have reported that concomitant infection with Schistosoma japonicum could offer protection against experimental cerebral malaria (ECM) in mice. This study was performed to evaluate whether alterations in parasite density could alter this protective effect. Methods Mice were inoculated with 100 or 200 S. japonicum cercariae followed by infection with high or low density of Plasmodium berghei ANKA strain eight weeks after the first infection. Then, parasitaemia, survival rate and blood–brain-barrier (BBB) damage were assessed. Interferon-gamma (IFN-γ), interleukin (IL)-4, IL-5, IL-13, IL-10, and TGF-β levels were determined in splenocyte supernatants using enzyme-linked immunosorbent assay (ELISA). Cell surface/intracellular staining and flow cytometry were used to analyse the level of CD4+/CD8+ T cells, CD4+CD25+Foxp3+ Tregs, IL-10-secreting Tregs, and IL-10+Foxp3-CD4+ T cells in the spleen, and CD4+/CD8+ T cells infiltrating the brain. Results Co-infection with low density P. berghei and increased S. japonicum cercariae significantly increased the levels of IL-4, IL-5, IL-13, TGF-β and Tregs, but significantly decreased the levels of IFN-γ and the percentage of CD4+ T cells and CD8+ T cells in the spleen and CD8+ T cell infiltration in the brain. Increased worm loads also significantly decreased mortality and BBB impairment during ECM. When challenged with higher numbers of P. berghei and increased cercariae, the observed cytokine changes were not statistically significant. The corresponding ECM mortality and BBB impairment also remained unchanged. Conclusions This study demonstrates that protection for ECM depends on the numbers of the parasites, S. japonicum and P. berghei, during co-infection. Alterations in the regulatory response appear to play a key role in this adaptation.

RNA interference (RNAi)-based short interfering RNAs (siRNAs) targeting the viral genes and the host cellular genes have been used to suppress Measles virus (MV) replication in vitro. In order to select suitable target genes and highly effective target sites for developing effective RNAi-mediated anti-MV therapy, in this study, nine short hairpin RNA (shRNA) expression vectors, which expressed siRNAs targeting the host celluar Rab9 GTPase gene, the viral large protein (L) gene and nucleoprotein (N) gene, respectively, were constructed and used to compare their ability to inhibit MV replication in Vero-E6 cells. The results showed that nine siRNAs targeting different genes exhibited different inhibitory efficacy on MV replication in vitro (about 23–94%), which could last at least 168 h post-infection. Of the nine siRNAs, R2, L1 and N2 more effectively decreased MV replication by over 90%. Furthermore, inhibitory efficacy on MV replication were increased and reached almost 100% when cells were transfected with pR2, pL1 and pN2 together. These results emphasis the importance of selecting suitable siRNA target sites for developing siRNAs-based drug therapy for MV, and demonstrate the potential of combination of siRNAs targeting different genes as a therapeutic approach to treat MV infection. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The aim of this study was to evaluate the effect of powered activated carbon (PAC) addition on algal water treatment by immerged ultrafiltration (UF) membrane, in terms of trans-membrane pressure (TMP) and permeate quality. Experiments were performed with a hollow-fibre polyvinyl chloride (PVC) ultrafiltration membrane at a laboratory scale, based on a time sequence of 120min filtration and 1min backwashing as a flux of 10L/(m2·h). UF achieved an absolute removal of M. aeruginosa cells, but poorly removed algal extracellular products resulting in severe membrane fouling. PAC addition with 4 g/L in the reactor controlled the increasing of TMP and enhanced the removal of DOC, UV254, as well as microsystins-LR, but could not efficiently improve the rejection of carbohydrates and proteins. Scanning electron microscopy (SEM) analysis was also employed to investigate the PAC effect on membrane fouling.

To investigate the insulin-like growth factor-I (IGF-I) gene and polypeptide expression in cultured rat osteoblast (ROB) and the role of IGF-I in mediating the cell-to-cell communication by mimicking the pharmacokinetics of parathyroid hormone (PTH).The ROB was cultured with three kinds of treatment: (1) Control (Ctr), the cells were cultured without PTH during the first 6 hours and the subsequent 42 hours in a 48-hour cycle; (2) Intermittent exposure to PTH (Itm), the cells were cultured with PTH during the first 6 hours, but without PTH in the subsequent 42 hours; and (3) Continuous exposure to PTH (Ctu), the cells were cultured with PTH during the first 6 hours and the subsequent 42 hours.The bone-forming activities of ROB were increased in Itm and inhibited in Ctu. The IGF-I mRNA content in Itm cells was elevated only during the first 6 hours and that in Ctu cells was elevated at any time during an incubation cycle. The free IGF-I concentration in the medium of Itm cells was generally higher and that of the Ctu cells was generally lower compared with those of the Ctr cells. The IGF-I antibody significantly reduced the alkaline phosphatase activity within the cells of Ctr and Itm.PTH rapidly and constantly stimulates the IGF-I gene transcription of osteoblast. There was an obvious discrepancy between the IGF-I mRNA content within the osteoblast and the free IGF-I level around the osteoblast in either mode of PTH action. The IGF-I might be important for osteoblast-osteoblast communication and bone-forming activity, not only in intermittent PTH administration, but also in the physiological functioning of osteoblasts.

Background We previously reported the use of a catheter system to damage the tricuspid valve and create infectious endocarditis (IE) in an animal model. The current study aims to create a faint IE model suitable for antibiotic prophylaxis using a low bacterial inoculum. We also aim to explore a way to quantitatively assess valvular impairment and to predict the success of the IE models during catheterization. Methods Ninety rabbits were assigned to two groups according to the density of bacteria inoculated (1 × 105 CFU for Group A and 1 × 104 CFU for Group B). A catheter system consisting of a polyethylene catheter and a guide wire were used to damage the valve. The catheter system was passed through the rabbits’ tricuspid valves under echocardiographic guidance. A pressure transducer was used to assess right atrial pressure (PRA) before and just after valvular damage to calculate the pressure alterations (ΔPRA). The animals in group A and B were divided into 3 subgroups according to the ΔPRA (0–5 mmHg for Groups A1 and B1; 5–10 mmHg for Groups A2 and B2; 10–15 mmHg for Groups A3 and B3). Staphylococcus aureus (ATCC 29213) inoculation was performed 24 hr after cardiac catheterization. Results Faint IE was confirmed in 20%, 93.3%, 26.7%, 6.7%, 20%, and 33.3% of the rabbits in Groups A1, A2, A3, B1, B2, and B3, respectively. There was no difference in the LV/RV ratio and VTR of the No-IE, faint-IE, and severe IE animals. Faint IE rabbits had a larger ΔPRA than No-IE rabbits (7.81 ± 1.21 vs. 2.48 ± 1.0, P