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1.
J Colloid Interface Sci ; 668: 50-58, 2024 Aug 15.
Article En | MEDLINE | ID: mdl-38669995

The ever-growing requirement for electrochemical energy storage has exacerbated the production of spent batteries, and the recycling of valuable battery components has recently received a remarkable attention. Among all battery components, copper foil is widely utilized as a current collector for stable zinc platting and stripping in zinc metal batteries (ZMBs) due to the perfect lattice matching of between metal copper and zinc, which is accompanied by the formation of multiple copper-zinc alloy components during the cycling process. Herein, a novel "two birds with one-stone" strategy through a one simple heat treatment step to revive the discarded copper foil in zinc metal battery is reported to further obtain a lithiophilic current collector (CuxZny-Cu) with multiple copper-zinc alloy components on the surface of the discarded copper foil. Such revived CuxZny-Cu current collector greatly reduces the lithium nucleation overpotential and realizes uniform lithium deposition and further inhibits lithium dendrites growth. The formed multiple CuxZny alloy phases on the surface of discarded copper foil exhibit a low Li nucleation overpotential of only 15 mV at 0.5 mA cm-2 for the first cycle. Moreover, such a CuxZny-Cu current collector could achieve stable cycle for 220 cycles at 0.5 mA cm-2 and 110 cycles at 1 mA cm-2 with a Li plating capacity of 1 mAh cm-2. Theoretical calculations indicate that, compared with pure Cu foil, the formed multiple alloy components of CuZn5, CuZn8, Cu0.61Zn0.39 and CuZn have low adsorption energy of -2.17, -2.55, -2.16 and -2.35 eV with lithium atoms, respectively, which result in reduced lithium nucleation overpotential. The full cell composed of CuxZny alloy current collector with deposition of 5 mAh cm-2 metal Li anode coupled with LiFePO4 (LFP) cathode exhibits a reversible capacity of 125.6 mAh/g after 110 cycles at a current of 0.5 C with capacity retention of 85.1 %. This work proposed a promising strategy to regenerate the discarded copper foil in rechargeable batteries.

2.
J Phys Chem Lett ; 15(9): 2542-2549, 2024 Mar 07.
Article En | MEDLINE | ID: mdl-38413398

Neuromorphic simulation, i.e., the use of electronic devices to simulate the neural networks of the human brain, has attracted a lot of interest in the fields of data processing and memory. This work provides a new method for preparing a 1,3-dimethylimidazolium nitrate ([MMIm][NO3]:H2O) microfluidic memristor that is ultralow cost and technically uncomplicated. Such a fluidic device uses capillaries as memory tubes, which are structurally similar to interconnected neurons by simple solution treatment. When voltage is applied, the transmission of anions and cations in the tube corresponds to the release of neurotransmitters from the presynaptic membrane to the postsynaptic membrane. The change of synaptic weights (plasticity) also can be simulated by the gradual change of conductance of the fluid memristor. The learning process of microfluidic memristors is very obvious, and the habituation and recovery behaviors they exhibit are extremely similar to biological activities, representing its good use for simulating neural synapses.

3.
Nanotechnology ; 33(24)2022 Mar 25.
Article En | MEDLINE | ID: mdl-35272277

In electrochemical metallization memristor, the performance of resistive switching (RS) is influenced by the forming and fusing of conductive filaments within the dielectric layer. However, the growth of filaments, mostly, is unpredictable and uncontrollable. For this reason, to optimize ions migration paths in the dielectric layer itself in the Al/CuxS/Cu structure, uniform CuxS nanosheets films have been synthesized using anodization for various time spans. And the Al/CuxS/Cu devices show a low operating voltage of less than 0.3 V and stable RS performance. At the same time, a reversible negative differential resistance (NDR) behavior is also demonstrated. And then, the mechanism of repeatable coexistence of RS effect and NDR phenomenon is investigated exhaustively. Analyses suggest that the combined physical model of space-charge limited conduction mechanism and conductive filaments bias-induced migration of Cu ions within the CuxS dielectric layer is responsible for the RS operation, meanwhile, a Schottky barrier caused by copper vacancy at the CuxS/Cu interface is demonstrated to explain the NDR phenomenon. This work will develop a new way to optimize the performance of non-volatile memory with multiple physical attributes in the future.

4.
Malar J ; 20(1): 374, 2021 Sep 19.
Article En | MEDLINE | ID: mdl-34538247

BACKGROUND: Plasmodium falciparum erythrocyte binding antigen-175 (PfEBA-175) is a candidate antigen for a blood-stage malaria vaccine, while various polymorphisms and dimorphism have prevented to development of effective vaccines based on this gene. This study aimed to investigate the dimorphism of PfEBA-175 on both the Bioko Island and continent of Equatorial Guinea, as well as the genetic polymorphism and natural selection of global PfEBA-175. METHODS: The allelic dimorphism of PfEBA-175 region II of 297 bloods samples from Equatorial Guinea in 2018 and 2019 were investigated by nested polymerase chain reaction and sequencing. Polymorphic characteristics and the effect of natural selection were analyzed using MEGA 7.0, DnaSP 6.0 and PopART programs. Protein function prediction of new amino acid mutation sites was performed using PolyPhen-2 and Foldx program. RESULTS: Both Bioko Island and Bata district populations, the frequency of the F-fragment was higher than that of the C-fragment of PfEBA-175 gene. The PfEBA-175 of Bioko Island and Bata district isolates showed a high degree of genetic variability and heterogeneity, with π values of 0.00407 & 0.00411 and Hd values of 0.958 & 0.976 for nucleotide diversity, respectively. The values of Tajima's D of PfEBA-175 on Bata district and Bioko Island were 0.56395 and - 0.27018, respectively. Globally, PfEBA-175 isolates from Asia were more diverse than those from Africa and South America, and genetic differentiation quantified by the fixation index between Asian and South American countries populations was significant (FST > 0.15, P < 0.05). A total of 310 global isolates clustered in 92 haplotypes, and only one cluster contained isolates from three continents. The mutations A34T, K109E, D278Y, K301N, L305V and D329N were predicted as probably damaging. CONCLUSIONS: This study demonstrated that the dimorphism of F-fragment PfEBA-175 was remarkably predominant in the study area. The distribution patterns and genetic diversity of PfEBA-175 in Equatorial Guinea isolates were similar another region isolates. And the levels of recombination events suggested that natural selection and intragenic recombination might be the main drivers of genetic diversity in global PfEBA-175. These results have important reference value for the development of blood-stage malaria vaccine based on this antigen.


Antigens, Protozoan/genetics , Plasmodium falciparum/genetics , Polymorphism, Genetic , Protozoan Proteins/genetics , Selection, Genetic , Adolescent , Adult , Aged , Child , Child, Preschool , Equatorial Guinea , Humans , Infant , Malaria, Falciparum/parasitology , Middle Aged , Young Adult
5.
Malar J ; 20(1): 124, 2021 Mar 02.
Article En | MEDLINE | ID: mdl-33653360

BACKGROUND: Thrombospondin-related adhesive protein (TRAP) is a transmembrane protein that plays a crucial role during the invasion of Plasmodium falciparum into liver cells. As a potential malaria vaccine candidate, the genetic diversity and natural selection of PfTRAP was assessed and the global PfTRAP polymorphism pattern was described. METHODS: 153 blood spot samples from Bioko malaria patients were collected during 2016-2018 and the target TRAP gene was amplified. Together with the sequences from database, nucleotide diversity and natural selection analysis, and the structural prediction were preformed using bioinformatical tools. RESULTS: A total of 119 Bioko PfTRAP sequences were amplified successfully. On Bioko Island, PfTRAP shows its high degree of genetic diversity and heterogeneity, with π value for 0.01046 and Hd for 0.99. The value of dN-dS (6.2231, p < 0.05) hinted at natural selection of PfTRAP on Bioko Island. Globally, the African PfTRAPs showed more diverse than the Asian ones, and significant genetic differentiation was discovered by the fixation index between African and Asian countries (Fst > 0.15, p < 0.05). 667 Asian isolates clustered in 136 haplotypes and 739 African isolates clustered in 528 haplotypes by network analysis. The mutations I116T, L221I, Y128F, G228V and P299S were predicted as probably damaging by PolyPhen online service, while mutations L49V, R285G, R285S, P299S and K421N would lead to a significant increase of free energy difference (ΔΔG > 1) indicated a destabilization of protein structure. CONCLUSIONS: Evidences in the present investigation supported that PfTRAP gene from Bioko Island and other malaria endemic countries is highly polymorphic (especially at T cell epitopes), which provided the genetic information background for developing an PfTRAP-based universal effective vaccine. Moreover, some mutations have been shown to be detrimental to the protein structure or function and deserve further study and continuous monitoring.


Malaria, Falciparum/parasitology , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Epitopes , Equatorial Guinea/epidemiology , Gene Frequency , Genetic Variation , Haplotypes , Humans , Malaria Vaccines , Malaria, Falciparum/epidemiology , Malaria, Falciparum/immunology , Plasmodium falciparum/immunology , Polymorphism, Genetic , Protozoan Proteins/chemistry , Protozoan Proteins/immunology , Selection, Genetic
6.
Front Cell Infect Microbiol ; 11: 613304, 2021.
Article En | MEDLINE | ID: mdl-33598439

Background: The emerging Coronavirus Disease-2019 (COVID-19) has challenged the public health globally. With the increasing requirement of detection for SARS-CoV-2 outside of the laboratory setting, a rapid and precise Point of Care Test (POCT) is urgently needed. Methods: Targeting the nucleocapsid (N) gene of SARS-CoV-2, specific primers, and probes for reverse transcription recombinase-aided amplification coupled with lateral flow dipstick (RT-RAA/LFD) platform were designed. For specificity evaluation, it was tested with human coronaviruses, human influenza A virus, influenza B viruses, respiratory syncytial virus, and hepatitis B virus, respectively. For sensitivity assay, it was estimated by templates of recombinant plasmid and pseudovirus of SARS-CoV-2 RNA. For clinical assessment, 100 clinical samples (13 positive and 87 negatives for SARS-CoV-2) were tested via quantitative reverse transcription PCR (RT-qPCR) and RT-RAA/LFD, respectively. Results: The limit of detection was 1 copies/µl in RT-RAA/LFD assay, which could be conducted within 30 min at 39°C, without any cross-reaction with other human coronaviruses and clinical respiratory pathogens. Compared with RT-qPCR, the established POCT assay offered 100% specificity and 100% sensitivity in the detection of clinical samples. Conclusion: This work provides a convenient POCT tool for rapid screening, diagnosis, and monitoring of suspected patients in SARS-CoV-2 endemic areas.


COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , COVID-19/virology , COVID-19 Nucleic Acid Testing/instrumentation , Coronavirus Nucleocapsid Proteins/genetics , DNA Primers/genetics , Humans , Phosphoproteins/genetics , Point-of-Care Testing , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/instrumentation , Recombinases/metabolism , Reverse Transcription , SARS-CoV-2/isolation & purification , Sensitivity and Specificity
7.
Malar J ; 19(1): 245, 2020 Jul 13.
Article En | MEDLINE | ID: mdl-32660484

BACKGROUND: Plasmodium falciparum circumsporozoite protein (PfCSP) is a potential malaria vaccine candidate, but various polymorphisms of the pfcsp gene among global P. falciparum population become the major barrier to the effectiveness of vaccines. This study aimed to investigate the genetic polymorphisms and natural selection of pfcsp in Bioko and the comparison among global P. falciparum population. METHODS: From January 2011 to December 2018, 148 blood samples were collected from P. falciparum infected Bioko patients and 96 monoclonal sequences of them were successfully acquired and analysed with 2200 global pfcsp sequences mined from MalariaGEN Pf3k Database and NCBI. RESULTS: In Bioko, the N-terminus of pfcsp showed limited genetic variations and the numbers of repetitive sequences (NANP/NVDP) were mainly found as 40 (35%) and 41 (34%) in central region. Most polymorphic characters were found in Th2R/Th3R region, where natural selection (p > 0.05) and recombination occurred. The overall pattern of Bioko pfcsp gene had no obvious deviation from African mainland pfcsp (Fst = 0.00878, p < 0.05). The comparative analysis of Bioko and global pfcsp displayed the various mutation patterns and obvious geographic differentiation among populations from four continents (p < 0.05). The global pfcsp C-terminal sequences were clustered into 138 different haplotypes (H_1 to H_138). Only 3.35% of sequences matched 3D7 strain haplotype (H_1). CONCLUSIONS: The genetic polymorphism phenomena of pfcsp were found universal in Bioko and global isolates and the majority mutations located at T cell epitopes. Global genetic polymorphism and geographical characteristics were recommended to be considered for future improvement of malaria vaccine design.


Plasmodium falciparum/genetics , Polymorphism, Genetic , Protozoan Proteins/genetics , Equatorial Guinea , Haplotypes , Selection, Genetic
8.
Infect Drug Resist ; 13: 1203-1212, 2020.
Article En | MEDLINE | ID: mdl-32431521

PURPOSE: Antimalarial drug resistance is one of the major challenges in global efforts to control and eliminate malaria. In 2006, sulfadoxine-pyrimethamine (SP) replaced with artemisinin-based combination therapy (ACT) on Bioko Island, Equatorial Guinea, in response to increasing SP resistance, which is associated with mutations in the dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes. PATIENTS AND METHODS: To evaluate the trend of molecular markers associated with SP resistance on Bioko Island from 2011 to 2017, 179 samples collected during active case detection were analysed by PCR and DNA sequencing. RESULTS: Pfdhfr and Pfdhps gene sequences were obtained for 90.5% (162/179) and 77.1% (138/179) of the samples, respectively. For Pfdhfr, 97.5% (158/162), 95.7% (155/162) and 98.1% (159/162) of the samples contained N51I, C59R and S108N mutant alleles, respectively. And Pfdhps S436A, A437G, K540E, A581G, and A613S mutations were observed in 25.4% (35/138), 88.4% (122/138), 5.1% (7/138), 1.4% (2/138), and 7.2% (10/138) of the samples, respectively. Two classes of previously described Pfdhfr-Pfdhps haplotypes associated with SP resistance and their frequencies were identified: partial (IRNI-SGKAA, 59.4%) and full (IRNI-SGEAA, 5.5%) resistance. Although no significant difference was observed in different time periods (p>0.05), our study confirmed a slowly increasing trend of the frequencies of these SP-resistance markers in Bioko parasites over the 7 years investigated. CONCLUSION: The findings reveal the general existence of SP-resistance markers on Bioko Island even after the replacement of SP as a first-line treatment for uncomplicated malaria. Continuous molecular monitoring and additional control efforts in the region are urgently needed.

9.
Risk Manag Healthc Policy ; 13: 303-311, 2020.
Article En | MEDLINE | ID: mdl-32308513

PURPOSE: Currently, thalassemia is commonly detected using gap-polymerase chain reaction (PCR) and deoxyribonucleic acid (DNA) reverse dot blot, which have high requirements of space, instruments, and personnel. Therefore, it is necessary to develop a new method for thalassemia detection with high sensitivity, low cost, and simple and fast operation. In this study, we aimed to design and evaluate a new method for detecting three α-thalassemia genes including -Southeast Asian (SEA), -α3.7, and -α4.2 and five ß-thalassemia genes including 654M, 41/42M, -28M, 17M, and 27/28M based on loop-mediated isothermal amplification (LAMP). METHODS: Primer sequences were designed using Primer Explorer V4 software. Blood samples (5 mL) were collected from all participants in EDTA. DNA was extracted using Chelex 100 and was subjected to LAMP. LAMP products were detected by fluorescence development in ultraviolet light. RESULTS: We found that LAMP assays for positive samples of thalassemia reached a plateau before 60 minutes, whereas the negative control samples entered the plateau after 70 minutes or showed no amplification. The concentration range of positive reactions was between 20-60 pg/µL and 20-60 ng/µL. Additionally, there were no cross-reactivities among 8 thalassemia subtypes. For clinical samples, the positive sample tube showed strong green fluorescence, whereas the negative tube showed light green fluorescence. According to these results, the LAMP method has high sensitivity for detecting thalassemia (252/254). However, 43 false-positive results were obtained in the LAMP test. The LAMP assay was also of low cost and with simple and fast operation. CONCLUSION: The novel LAMP assay can be completed within 60 min using a heating block or a water bath, and the result can be read visually based on color change to detect thalassemia. The LAMP assay fulfills the requirements of field application and resource-limited areas, especially those with primary hospitals and rural areas.

10.
Mol Genet Genomic Med ; 8(2): e1061, 2020 02.
Article En | MEDLINE | ID: mdl-31872983

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage. Although G6PD-deficient alleles appear to confer a protective effect of malaria, the link with clinical protection against Plasmodium infection is conflicting. METHODS: A case-control study was conducted on Bioko Island, Equatorial Guinea and further genotyping analysis used to detect natural selection of the G6PD A- allele. RESULTS: Our results showed G6PD A- allele could significantly reduce the risk of Plasmodium falciparum infection in male individuals (adjusted odds ratio [AOR], 0.43; 95% confidence interval [CI], 0.20-0.93; p < .05) and homozygous female individuals (AOR, 0.11; 95% CI, 0.01-0.84; p < .05). Additionally, the parasite densities were significantly different in the individuals with different G6PD A- alleles and individual levels of G6PD enzyme activity. The pattern of linkage disequilibrium and results of the long-range haplotype test revealed a strong selective signature in the region encompassing the G6PD A- allele over the past 6,250 years. The network of inferred haplotypes suggested a single origin of the G6PD A- allele in Africans. CONCLUSION: Our findings demonstrate that glucose-6-phosphate dehydrogenase (G6PD) A- allele could reduce the risk of P. falciparum infection in the African population and indicate that malaria has a recent positive selection on G6PD A- allele.


Alleles , Glucosephosphate Dehydrogenase/genetics , Malaria/genetics , Population/genetics , Selection, Genetic , Adolescent , Adult , Black People/genetics , Child , Child, Preschool , Female , Guinea , Homozygote , Humans , Infant , Islands , Linkage Disequilibrium , Male , Plasmodium falciparum/pathogenicity , Polymorphism, Single Nucleotide
11.
Malar J ; 18(1): 317, 2019 Sep 18.
Article En | MEDLINE | ID: mdl-31533747

BACKGROUND: Plasmodium falciparum apical membrane antigen-1 (PfAMA-1) is a promising candidate antigen for a blood-stage malaria vaccine. However, antigenic variation and diversity of PfAMA-1 are still major problems to design a universal malaria vaccine based on this antigen, especially against domain I (DI). Detail understanding of the PfAMA-1 gene polymorphism can provide useful information on this potential vaccine component. Here, general characteristics of genetic structure and the effect of natural selection of DIs among Bioko P. falciparum isolates were analysed. METHODS: 214 blood samples were collected from Bioko Island patients with P. falciparum malaria between 2011 and 2017. A fragment spanning DI of PfAMA-1 was amplified by nested polymerase chain reaction and sequenced. Polymorphic characteristics and the effect of natural selection were analysed using MEGA 5.0, DnaSP 6.0 and Popart programs. Genetic diversity in 576 global PfAMA-1 DIs were also analysed. Protein function prediction of new amino acid mutation sites was performed using PolyPhen-2 program. RESULTS: 131 different haplotypes of PfAMA-1 were identified in 214 Bioko Island P. falciparum isolates. Most amino acid changes identified on Bioko Island were found in C1L. 32 amino acid changes identified in PfAMA-1 sequences from Bioko Island were found in predicted RBC-binding sites, B cell epitopes or IUR regions. Overall patterns of amino acid changes of Bioko PfAMA-1 DIs were similar to those in global PfAMA-1 isolates. Differential amino acid substitution frequencies were observed for samples from different geographical regions. Eight new amino acid changes of Bioko island isolates were also identified and their three-dimensional protein structural consequences were predicted. Evidence for natural selection and recombination event were observed in global isolates. CONCLUSIONS: Patterns of nucleotide diversity and amino acid polymorphisms of Bioko Island isolates were similar to those of global PfAMA-1 DIs. Balancing natural selection across DIs might play a major role in generating genetic diversity in global isolates. Most amino acid changes in DIs occurred in predicted B-cell epitopes. Novel sites mapped on a three dimensional structure of PfAMA-1 showed that these regions were located at the corner. These results may provide significant value in the design of a malaria vaccine based on this antigen.


Antigens, Protozoan/genetics , Genetic Variation , Membrane Proteins/genetics , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Selection, Genetic , Antigens, Protozoan/metabolism , Equatorial Guinea , Membrane Proteins/metabolism , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism
12.
Cell Physiol Biochem ; 52(6): 1503-1516, 2019.
Article En | MEDLINE | ID: mdl-31112017

BACKGROUND/AIMS: Zinc Finger Protein 281 (ZNF281) was recently identified as a novel oncogene in several human carcinomas. However, the clinical significance of ZNF281 in colorectal cancer (CRC) and the molecular mechanisms by which ZNF281 promotes the growth and metastasis of CRC remain unknown. METHODS: ZNF281 expression in CRC tissues was assessed, and the outcomes were analyzed to determine the clinical importance of ZNF281 expression. Cell Transwell assays and a wound healing assay were performed to assess the effects of ZNF281 on CRC cell migration and invasion in vitro. Western blotting was applied to analyze the potential mechanisms. RESULTS: ZNF281 mRNA and protein levels were significantly increased in CRC tissues compared with normal colon tissues, and high ZNF281 expression was associated with advanced T stage, N stage, TNM stage and differentiation. Therefore, ZNF281 expression might be an independent prognostic indicator in CRC patients. Moreover, knockdown of ZNF281 expression suppressed cell proliferation, migration and invasion by inhibiting the Wnt/ß-catenin pathway. CONCLUSION: Our study indicates that ZNF281 plays a critical role in the progression and metastasis of CRC and could represent a potential therapeutic target for CRC.


Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Trans-Activators/metabolism , Aged , Cell Line, Tumor , Cell Movement/genetics , Cell Movement/physiology , Cell Proliferation/genetics , Cell Proliferation/physiology , Colorectal Neoplasms/genetics , Disease Progression , Female , Gene Expression Regulation, Neoplastic , HCT116 Cells , HT29 Cells , Humans , Male , Middle Aged , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Neoplasm Invasiveness/physiopathology , Prognosis , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , RNA, Small Interfering/genetics , Repressor Proteins , Trans-Activators/antagonists & inhibitors , Trans-Activators/genetics , Up-Regulation , Wnt Signaling Pathway , beta Catenin/metabolism
13.
Sheng Li Xue Bao ; 71(1): 62-72, 2019 Feb 25.
Article Zh | MEDLINE | ID: mdl-30778505

Visual memory, mainly composed of visual long-term memory (VLTM) and visual working memory (VWM), is an important mechanism of human information storage. Since Baddeley proposed the multicomponent working memory model, the idea that VWM is independent of the VLTM system has been widely accepted. However, the new theoretical evidence suggested a close connection between VLTM and VWM. For instance, the three embedded components model describes the VLTM and VWM in the same framework, which suggests that VWM is only a distinct state of VLTM. On the one hand, the operating function of VWM is supported by the persistence of VLTM. On the other hand, the evidence from neuroimaging studies shows that VWM and VLTM tasks activate some same brain areas. In addition, the whole visual memory system shows a trend of processing from early visual cortex to prefrontal cortex. The present article not only reviews the current studies about the relationship between VLTM and VWM but also gives some forecasts for future studies.


Memory, Long-Term , Memory, Short-Term , Visual Cortex/physiology , Visual Perception , Brain/physiology , Humans
14.
Malar J ; 17(1): 458, 2018 Dec 07.
Article En | MEDLINE | ID: mdl-30526609

BACKGROUND: Malaria is still a serious public health problem on Bioko Island (Equatorial Guinea), although the number of annual cases has been greatly reduced since 2004 through the Bioko Island Malaria Control Project (BIMCP). 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 the genetic diversity of Plasmodium falciparum populations and multiplicity of infection (MOI) on Bioko Island 7 years after BIMCP. METHODS: A total of 181 patients with uncomplicated P. falciparum malaria diagnosed with microscopy were collected from Bioko Island from January 2011 to December 2014. Parasite DNA was extracted using chelex-100 and species were identified using a real-time PCR followed by high-resolution melting. Plasmodium falciparum msp1 and msp2 allelic families were determined using nested PCR. RESULTS: Three msp1 alleles (K1, MAD20, and RO33) and two msp2 alleles (FC27 and 3D7) were analysed in all samples. In msp1, the MAD20 allelic family was predominant with 96.69% (175/178) followed respectively by the K1 allelic family with 96.07% (171/178) and R033 allelic family with 70.78% (126/178). In msp2, the FC27 allelic family was the most frequently detected with 97.69% (169/173) compared to 3D7 with 72.25% (125/173). Twenty-six different alleles were observed in msp1 with 9 alleles for K1, 9 alleles for MAD20 and 8 alleles for R033. In msp2, 25 individual alleles were detected with 5 alleles for FC27 and 20 alleles for 3D7. The overall MOI was 5.51 with respectively 3.5 and 2.01 for msp1 and msp2. A significant increase in overall MOI was correlated with the age group of the patients (P = 0.026) or parasite densities (P = 0.04). CONCLUSIONS: The present data showed high genetic diversity and MOI values among the P. falciparum population in the study, reflecting both the high endemic level and malaria transmission on Bioko Island. These data provide valuable information for surveillance of P. falciparum infection and for assessing the appropriateness of the current malarial control strategies in the endemic area.


Antigens, Protozoan/genetics , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Merozoite Surface Protein 1/genetics , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Adolescent , Adult , Child , Child, Preschool , DNA, Protozoan/genetics , Equatorial Guinea/epidemiology , Female , Gene Frequency/genetics , Genetic Variation/genetics , Humans , Infant , Infant, Newborn , Male , Middle Aged , Molecular Epidemiology , Young Adult
15.
Afr J AIDS Res ; 16(1): 65-70, 2017 Mar.
Article En | MEDLINE | ID: mdl-28367743

Malaria and HIV are two of the most severe public health problems in Africa. However, epidemiological data on Bioko Island is scarce. To investigate the prevalence of malaria and HIV infections and assess association of malaria and HIV infections and possible confounding factors, we performed a cross-sectional survey of people of malaria-endemic Bioko Island, Equatorial Guinea. A cross-sectional study of 1 526 subjects was carried out to determine the prevalence of malaria and HIV infection in Malabo region hospital on Bioko Island. Questionnaires were administered and venous blood samples were drawn for malaria parasites and HIV detection. The prevalence of participants infected with malaria and HIV in this area were 13.8% and 6.6% respectively. The average prevalence of co-infection for malaria and HIV was 0.92%. HIV-infection was significantly associated with the age and gender. Malaria infections were significantly associated with the age. This study showed that the prevalence of HIV and malaria on Bioko Island was higher than expected, although the co-infection prevalence of malaria and HIV was low. The results also indicated that malaria and HIV infections lead to more public health risk to youngsters and women.


HIV Infections/epidemiology , Malaria/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Coinfection , Cross-Sectional Studies , Equatorial Guinea/epidemiology , Female , Humans , Infant , Islands , Malaria/parasitology , Male , Middle Aged , Odds Ratio , Parasite Load , Population Surveillance , Prevalence , Risk Factors , Young Adult
16.
Biomed Pharmacother ; 85: 472-478, 2017 Jan.
Article En | MEDLINE | ID: mdl-27890434

Hepatocellular carcinoma (HCC) is a highly aggressive solid malignancy in the word. Aberrant microRNA (miRNA) expression is involved in human diseases including cancer. In the current study, we explore the function of miR-98 in HCC cell proliferation. We found that expression level of miR-98 was significantly decreased in HCC tissues and cells lines compared with adjacent non-tumor issues and human hepatic cell line LO2. Increased expression of miR-98 suppressed HCC cell proliferation and arrested HCC cell cycle in G0/G1 phase. While, suppressed expression of miR-98 showed the opposite effect. Bioinformatics analysis revealed EZH2, a putative tumor promoter as a potential target of miR-98. Additionally, luciferase reporter assay revealed that miR-98 directly binds to the 3'-untranslated region (3'-UTR) of EZH2 mRNA. Furthermore, we demonstrated that miR-98 could reduce the Wnt/ß-catenin signal pathway by suppressing EZH2 directly. Moreover, inhibition of EZH2 abrogated the effect of miR-98 inhibitor on HCC cell proliferation. Taken together, these results suggested that miR-98 functioned as a potential tumor suppressor by regulating Wnt/ß-catenin signal pathway through direct suppression of EZH2 expression and might sever as a potential therapeutic target for HCC patients.


Carcinoma, Hepatocellular/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Wnt Proteins/metabolism , beta Catenin/metabolism , Cell Line, Tumor , Down-Regulation , Enhancer of Zeste Homolog 2 Protein/genetics , Gene Expression Regulation/physiology , Humans , MicroRNAs/genetics , Signal Transduction/physiology , Wnt Proteins/genetics , beta Catenin/genetics
17.
Afr. j. AIDS res. (Online) ; 16(1): 65-70, 2017.
Article En | AIM | ID: biblio-1256624

Malaria and HIV are two of the most severe public health problems in Africa. However, epidemiological data on Bioko Island is scarce. To investigate the prevalence of malaria and HIV infections and assess association of malaria and HIV infections and possible confounding factors, we performed a cross-sectional survey of people of malaria-endemic Bioko Island, Equatorial Guinea. A cross-sectional study of 1 526 subjects was carried out to determine the prevalence of malaria and HIV infection in Malabo region hospital on Bioko Island. Questionnaires were administered and venous blood samples were drawn for malaria parasites and HIV detection. The prevalence of participants infected with malaria and HIV in this area were 13.8% and 6.6% respectively. The average prevalence of co-infection for malaria and HIV was 0.92%. HIV-infection was significantly associated with the age and gender. Malaria infections were significantly associated with the age. This study showed that the prevalence of HIV and malaria on Bioko Island was higher than expected, although the co-infection prevalence of malaria and HIV was low. The results also indicated that malaria and HIV infections lead to more public health risk to youngsters and women


Coinfection , Equatorial Guinea , HIV Infections , Malaria , Prevalence
18.
Medicine (Baltimore) ; 95(35): e4658, 2016 Aug.
Article En | MEDLINE | ID: mdl-27583887

BACKGROUND: Hypereosinophilic syndrome (HES) can be fatal, particularly when eosinophils infiltrate vital organs and/or if extensive thrombosis develops. However there are no standard recommendations for the use of anticoagulant therapy of HES in the setting of thrombosis. METHODS: We herein present a case of a 46-year-old female who presented with marked peripheral eosinophilia with symptoms of multi-organ infiltration and extensive deep venous thrombosis (DVT). In this case, evaluation was carried out before the diagnosis was established, and timely standard-dose corticosteroids combined with a new oral anticoagulant (NOAC) therapy were carried out. RESULTS: These measures resulted in a rapid response and long-term disease control. CONCLUSION: Although there are no data to support which anticoagulant is preferred in this setting, this case indicates that the new oral anticoagulants may play an important role in the treatment of thrombosis in HES.


Anti-Inflammatory Agents/therapeutic use , Factor Xa Inhibitors/therapeutic use , Hypereosinophilic Syndrome/complications , Hypereosinophilic Syndrome/drug therapy , Prednisolone/therapeutic use , Rivaroxaban/therapeutic use , Venous Thrombosis/drug therapy , Venous Thrombosis/etiology , Combined Modality Therapy , Female , Humans , Hypereosinophilic Syndrome/pathology , Kidney/pathology , Liver/pathology , Middle Aged , Platelet Transfusion , Thorax/pathology
19.
Contemp Oncol (Pozn) ; 20(1): 73-9, 2016.
Article En | MEDLINE | ID: mdl-27095944

UNLABELLED: Hemipelvic resections for primary bone tumours require reconstruction to restore weight bearing along anatomic axes. However, reconstruction of the pelvic arch remains a major surgical challenge because of the high rate of associated complications. We used the pedicle screw-rod system to reconstruct the pelvis, and the purpose of this investigation was to assess the oncology, functional outcome and complication rate following this procedure. The purpose of this study was to investigate the operative indications and technique of the pedicle screw-rod system in reconstruction of the stability of the sacroiliac joint after resection of sacroiliac joint tumours. The average MSTS (Musculoskeletal Tumour Society) score was 26.5 at either three months after surgery or at the latest follow-up. Seven patients had surgery-related complications, including wound dehiscence in one, infection in two, local necrosis in four (including infection in two), sciatic nerve palsy in one and pubic symphysis subluxation in one. There was no screw loosening or deep vein thrombosis occurring in this series. Using a pedicle screw-rod after resection of a sacroiliac joint tumour is an acceptable method of pelvic reconstruction because of its reduced risk of complications and satisfactory functional outcome, as well as its feasibility of reconstruction for type IV pelvis tumour resection without elaborate preoperative customisation. LEVEL OF EVIDENCE: Level IV, therapeutic study.

20.
Mol Med Rep ; 13(3): 2639-44, 2016 Mar.
Article En | MEDLINE | ID: mdl-26846175

MicroRNAs (miRNAs) are emerging as critical regulators in carcinogenesis and tumor progression. miR-98 has previously been verified to be important in tumor progression, however, its function in hepatocellular carcinoma (HCC) remains to be elucidated. The expression levels of miR-98 in HCC tissues and cell lines were determined by reverse transcription quantitative polymerase chain reaction. Subsequently, the effect of miR­98 on cell proliferation, migration and invasion was evaluated by MTT assay, transwell migration assay and transwell invasion assay. Furthermore, a luciferase reporter assay was conducted to confirm the action of miR­98 on downstream target genes, including collagen triple helix repeat containing 1 (CTHRC1). In the present study, it was confirmed that miR­98 was significantly downregulated in HCC tissues and cell lines. Overexpression of miR­98 inhibited HCC cell proliferation, migration and invasion in vitro. In addition, at the molecular level, the tumor oncogene CTHRC1 was identified to be the direct target of miR-98. Our findings suggested that miR­98 was significantly downregulated in HCC and suppressed HCC cell proliferation, migration and invasion partially via the downregulation of CTHRC1. Thus, these data demonstrated that miR-98 could be a potential therapeutic target in HCC.


Carcinoma, Hepatocellular/metabolism , Extracellular Matrix Proteins/metabolism , Liver Neoplasms/metabolism , MicroRNAs/physiology , Carcinoma, Hepatocellular/drug therapy , Cell Line, Tumor , Cell Movement , Cell Proliferation , Down-Regulation , Extracellular Matrix Proteins/genetics , Gene Knockdown Techniques , Humans , Liver Neoplasms/drug therapy , MicroRNAs/genetics , MicroRNAs/therapeutic use , Neoplasm Invasiveness
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