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1.
Chem Rev ; 123(11): 7119-7192, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36749705

RESUMO

Since severe global warming and related climate issues have been caused by the extensive utilization of fossil fuels, the vigorous development of renewable resources is needed, and transformation into stable chemical energy is required to overcome the detriment of their fluctuations as energy sources. As an environmentally friendly and efficient energy carrier, hydrogen can be employed in various industries and produced directly by renewable energy (called green hydrogen). Nevertheless, large-scale green hydrogen production by water electrolysis is prohibited by its uncompetitive cost caused by a high specific energy demand and electricity expenses, which can be overcome by enhancing the corresponding thermodynamics and kinetics at elevated working temperatures. In the present review, the effects of temperature variation are primarily introduced from the perspective of electrolysis cells. Following an increasing order of working temperature, multidimensional evaluations considering materials and structures, performance, degradation mechanisms and mitigation strategies as well as electrolysis in stacks and systems are presented based on elevated temperature alkaline electrolysis cells and polymer electrolyte membrane electrolysis cells (ET-AECs and ET-PEMECs), elevated temperature ionic conductors (ET-ICs), protonic ceramic electrolysis cells (PCECs) and solid oxide electrolysis cells (SOECs).

2.
J Synchrotron Radiat ; 31(Pt 4): 968-978, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38917022

RESUMO

The BL17B beamline at the Shanghai Synchrotron Radiation Facility was first designed as a versatile high-throughput protein crystallography beamline and one of five beamlines affiliated to the National Facility for Protein Science in Shanghai. It was officially opened to users in July 2015. As a bending magnet beamline, BL17B has the advantages of high photon flux, brightness, energy resolution and continuous adjustable energy between 5 and 23 keV. The experimental station excels in crystal screening and structure determination, providing cost-effective routine experimental services to numerous users. Given the interdisciplinary and green energy research demands, BL17B beamline has undergone optimization, expanded its range of experimental methods and enhanced sample environments for a more user-friendly testing mode. These methods include single-crystal X-ray diffraction, powder crystal X-ray diffraction, wide-angle X-ray scattering, grazing-incidence wide-angle X-ray scattering (GIWAXS), and fully scattered atom pair distribution function analysis, covering structure detection from crystalline to amorphous states. This paper primarily presents the performance of the BL17B beamline and the application of the GIWAXS methodology at the beamline in the field of perovskite materials.

3.
Mol Carcinog ; 62(4): 517-531, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36645220

RESUMO

Esophageal squamous cell carcinoma (ESCC) accounts for 90% of esophageal cancers and has a high mortality rate worldwide. The 5-year survival rate of ESCC patients in developing countries is <20%. Hence, there is an urgent need for developing new and effective treatments that are based on newly-discovered emerging molecules and pathways to prevent ESCC occurrence and recurrence. We investigated the effects of Daurisoline, a bis-benzylisoquinoline alkaloid extracted from the rhizome of menisperum dauricum, on ESCC cell proliferation and elucidated the molecular mechanisms underlying its functions. To explore the effects of Daurisoline on ESCC growth in vitro and in vivo, cell proliferation assays and anchorage-independent growth assays were performed and a patient-derived xenograft (PDX) model was established. Subsequently, phosphoproteomics, molecular docking analysis, pull down assays, mutation experiments and in vitro kinase assay were performed to explore the mechanism of Daurisoline's function on ESCC. Daurisoline inhibited ESCC proliferation in vitro and reduced ESCC PDX exnograft growth in vivo by reducing ERK1/2 phosphorylation. Furthermore, it directly bound to MEK1 (at Asn78 and Lys97) and MEK2 (at Asp194 and Asp212) kinases to inactivate the ERK1/2 signaling pathway. Our results suggest that Daurisoline is a dual inhibitor of MEK1 and MEK2 and suppresses ESCC growth both in vitro and in vivo by inactivating the ERK1/2 signaling pathway. This is first report on the use of MEK inhibitor for ESCC and highlights its potential applications for ESCC treatment and prevention.


Assuntos
Benzilisoquinolinas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Simulação de Acoplamento Molecular , Proliferação de Células , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Benzilisoquinolinas/farmacologia , Regulação Neoplásica da Expressão Gênica
4.
J Hum Genet ; 68(1): 11-16, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36316471

RESUMO

The vast majority of epidemiological studies suggested a link between systemic lupus erythematosus (SLE) and major depressive disorder (MDD). However, the causality for SLE on the risk of MDD remained unknown due to confounding factors or reverse causality. Herein, we investigated the causality between SLE and MDD in those of European ancestry by a Mendelian randomization (MR) approach. Summary genetic data of cases with SLE/MDD were derived from independent largest public genome-wide association study. Forty-six single nucleotide polymorphisms associated with SLE were used as instrumental variables. The main causal inference was carried out using the MRE-IVW method. Additional, reverse-direction MR and multivariable MR analyses were further performed. Result indicated that SLE was causally associated with a lower risk of MDD (using the MRE-IVW method, odds ratio [OR] = 0.983, 95% confidence interval [CI] = 0.974-0.991, p = 1.18 × 10-4). Complementary analysis found no heterogeneity or horizontal pleiotropy. Multivariate MR analysis yielded consistent results (OR = 0.981; 95% CI = 0.969-0.993; p = 2.75 × 10-3). Reverse-direction MR analysis suggested non-causal relationship of MDD on the risk of SLE (using the IVW method, OR = 0.846, 95% CI = 0.345-2.072; p = 0.714). Thus, this is the first study providing evidence of potential causal links between SLE and MDD and further related research is needed.


Assuntos
Transtorno Depressivo Maior , Lúpus Eritematoso Sistêmico , Humanos , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Análise da Randomização Mendeliana/métodos , Estudo de Associação Genômica Ampla , Causalidade , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único
5.
J Virol ; 95(9)2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33627391

RESUMO

Influenza A viruses (IAVs) continue to pose an imminent threat to humans due to annual influenza epidemic outbreaks and episodic pandemics with high mortality rates. In this context, the suboptimal vaccine coverage and efficacy, coupled with recurrent events of viral resistance against a very limited antiviral portfolio, emphasize an urgent need for new additional prophylactic and therapeutic options, including new antiviral targets and drugs with new mechanisms of action to prevent and treat influenza virus infection. Here, we characterized a novel influenza A virus nucleoprotein (NP) inhibitor, FA-6005, that inhibited a broad spectrum of human pandemic and seasonal influenza A and B viruses in vitro and protects mice against lethal influenza A virus challenge. The small molecule FA-6005 targeted a conserved NP I41 domain and acted as a potentially broad, multimechanistic anti-influenza virus therapeutic since FA-6005 suppressed influenza virus replication and perturbed intracellular trafficking of viral ribonucleoproteins (vRNPs) from early to late stages. Cocrystal structures of the NP/FA-6005 complex reconciled well with concurrent mutational studies. This study provides the first line of direct evidence suggesting that the newly identified NP I41 pocket is an attractive target for drug development that inhibits multiple functions of NP. Our results also highlight FA-6005 as a promising candidate for further development as an antiviral drug for the treatment of IAV infection and provide chemical-level details for inhibitor optimization.IMPORTANCE Current influenza antivirals have limitations with regard to their effectiveness and the potential emergence of resistance. Therefore, there is an urgent need for broad-spectrum inhibitors to address the considerable challenges posed by the rapid evolution of influenza viruses that limit the effectiveness of vaccines and lead to the emergence of antiviral drug resistance. Here, we identified a novel influenza A virus NP antagonist, FA-6005, with broad-spectrum efficacy against influenza viruses, and our study presents a comprehensive study of the mode of action of FA-6005 with the crystal structure of the compound in complex with NP. The influenza virus inhibitor holds promise as an urgently sought-after therapeutic option offering a mechanism of action complementary to existing antiviral drugs for the treatment of influenza virus infection and should further aid in the development of universal therapeutics.


Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Proteínas do Nucleocapsídeo , Replicação Viral/efeitos dos fármacos , Animais , Cães , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Proteínas do Nucleocapsídeo/antagonistas & inibidores , Proteínas do Nucleocapsídeo/metabolismo , Infecções por Orthomyxoviridae/prevenção & controle , Ligação Proteica
6.
Nat Mater ; 20(2): 222-228, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33230325

RESUMO

Electrically conducting 2D metal-organic frameworks (MOFs) have attracted considerable interest, as their hexagonal 2D lattices mimic graphite and other 2D van der Waals stacked materials. However, understanding their intrinsic properties remains a challenge because their crystals are too small or of too poor quality for crystal structure determination. Here, we report atomically precise structures of a family of 2D π-conjugated MOFs derived from large single crystals of sizes up to 200 µm, allowing atomic-resolution analysis by a battery of high-resolution diffraction techniques. A designed ligand core rebalances the in-plane and out-of-plane interactions that define anisotropic crystal growth. We report two crystal structure types exhibiting analogous 2D honeycomb-like sheets but distinct packing modes and pore contents. Single-crystal electrical transport measurements distinctively demonstrate anisotropic transport normal and parallel to the π-conjugated sheets, revealing a clear correlation between absolute conductivity and the nature of the metal cation and 2D sheet packing motif.

7.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35806248

RESUMO

The major facilitator superfamily (MFS) is the largest secondary transporter family and is responsible for transporting a broad range of substrates across the biomembrane. These proteins are involved in a series of conformational changes during substrate transport. To decipher the transport mechanism, it is necessary to obtain structures of these different conformations. At present, great progress has been made in predicting protein structure based on coevolutionary information. In this study, AlphaFold2 was used to predict different conformational structures for 69 MFS transporters of E. coli after the selective mutation of residues at the interface between the N- and C-terminal domains. The predicted structures for these mutants had small RMSD values when compared to structures obtained using X-ray crystallography, which indicates that AlphaFold2 predicts the structure of MSF transporters with high accuracy. In addition, different conformations of other transporter family proteins have been successfully predicted based on mutation methods. This study provides a structural basis to study the transporting mechanism of the MFS transporters and a method to probe dynamic conformation changes of transporter family proteins when performing their function.


Assuntos
Escherichia coli , Proteínas de Membrana Transportadoras , Cristalografia por Raios X , Escherichia coli/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Modelos Moleculares , Mutação , Conformação Proteica
8.
Comput Electr Eng ; 102: 108212, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35821875

RESUMO

Corona Virus Disease 2019 (COVID-19) has led to an increase in attacks targeting widespread smart devices. A vulnerable device can join multiple botnets simultaneously or sequentially. When different attack patterns are mixed with attack records, the security analyst produces an inaccurate report. There are numerous studies on botnet detection, but there is no publicly available solution to classify attack patterns based on the control periods. To fill this gap, we propose a novel data-driven method based on an intuitive hypothesis: bots tend to show time-related attack patterns within the same botnet control period. We deploy 462 honeypots in 22 countries to capture real-world attack activities and propose an algorithm to identify control periods. Experiments have demonstrated our method's efficacy. Besides, we present eight interesting findings that will help the security community better understand and fight botnet attacks now and in the future.

9.
Bioorg Med Chem ; 29: 115902, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33302045

RESUMO

ß-lactam antibiotics have long been the mainstay for the treatment of bacterial infections. New Delhi metallo-ß-lactamase 1 (NDM-1) is able to hydrolyze nearly all ß-lactam antibiotics and even clinically used serine-ß-lactamase inhibitors. The wide and rapid spreading of NDM-1 gene among pathogenic bacteria has attracted extensive attention, therefore high potency NDM-1 inhibitors are urgently needed. Here we report a series of structure-guided design of D-captopril derivatives that can inhibit the activity of NDM-1 in vitro and at cellular levels. Structural comparison indicates the mechanisms of inhibition enhancement and provides insights for further inhibitor optimization.


Assuntos
Antibacterianos/química , Captopril/química , Inibidores de beta-Lactamases/química , beta-Lactamases/metabolismo , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Sítios de Ligação , Captopril/metabolismo , Captopril/farmacologia , Cristalografia por Raios X , Descoberta de Drogas , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Humanos , Hidrólise/efeitos dos fármacos , Modelos Moleculares , Ligação Proteica , Relação Estrutura-Atividade , Compostos de Sulfidrila/química , Inibidores de beta-Lactamases/metabolismo , Inibidores de beta-Lactamases/farmacologia
10.
Entropy (Basel) ; 23(11)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34828187

RESUMO

Insecure applications (apps) are increasingly used to steal users' location information for illegal purposes, which has aroused great concern in recent years. Although the existing methods, i.e., static and dynamic taint analysis, have shown great merit for identifying such apps, which mainly rely on statically analyzing source code or dynamically monitoring the location data flow, identification accuracy is still under research, since the analysis results contain a certain false positive or true negative rate. In order to improve the accuracy and reduce the misjudging rate in the process of vetting suspicious apps, this paper proposes SAMLDroid, a combined method of static code analysis and machine learning for identifying Android apps with location privacy leakage, which can effectively improve the identification rate compared with existing methods. SAMLDroid first uses static analysis to scrutinize source code to investigate apps with location acquiring intentions. Then it exploits a well-trained classifier and integrates an app's multiple features to dynamically analyze the pattern and deliver the final verdict about the app's property. Finally, it is proved by conducting experiments, that the accuracy rate of SAMLDroid is up to 98.4%, which is nearly 20% higher than Apparecium.

11.
Parasitol Res ; 117(1): 169-175, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29177580

RESUMO

Cryptosporidium spp. are common intestinal protozoa causing diarrhea in humans and a variety of animal species. With the recent development of fur industry, a large number of fur animals are farmed worldwide, especially in China. The existence of identical Cryptosporidium species/genotypes in humans and fur animals suggests zoonotic potential. In order to assess the presence of zoonotic Cryptosporidium species and/or genotypes in farmed fur animals, 367 fecal specimens were collected from 213 foxes, 114 minks and 40 raccoon dogs farmed in Heilongjiang, Jilin, and Liaoning provinces, northeastern China, during the period from June 2014 to October 2016. By PCR and sequencing of the partial small subunit (SSU) rRNA gene of Cryptosporidium, 20 of 367 (5.4%) animal samples were found to be infected, corresponding to 12 of 213 fox samples (5.6%) and 8 of 114 mink samples (7.0%) screened. Three Cryptosporidium species/genotypes were identified: C. canis (n = 17), C. meleagridis (n = 1) and Cryptosporidium mink genotype (n = 2). Two host-adapted C. canis types (C. canis dog genotype and C. canis fox genotype) were found. By PCR and sequencing of the partial 60 kDa glycoprotein (gp60) encoding gene, one mink genotype isolate was successfully subtyped as XcA5G1R1. The three Cryptosporidium species/genotypes identified in this study have been previously reported in humans suggesting that fur animals infected with Cryptosporidium spp. may pose a risk of zoonotic transmission of cryptosporidiosis, especially for the people working in fur animal farming and processing industry.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Raposas/parasitologia , Vison/parasitologia , Cães Guaxinins/parasitologia , Animais , China , Cryptosporidium/classificação , Fezes/parasitologia , Genótipo , Humanos , Reação em Cadeia da Polimerase
12.
Sensors (Basel) ; 18(12)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513945

RESUMO

WirelessHART is a wireless sensor network that is widely used in real-time demand analyses. A key challenge faced by WirelessHART is to ensure the character of real-time data transmission in the network. Identifying a priority assignment strategy that reduces the delay in flow transmission is crucial in ensuring real-time network performance and the schedulability of real-time network flows. We study the priority assignment of real-time flows in WirelessHART on the basis of the multi-channel time division multiple access (TDMA) protocol to reduce the delay and improve the ratio of scheduled. We provide three kinds of methods: (1) worst fit, (2) best fit, and (3) first fit and choose the most suitable one, namely the worst-fit method for allocating flows to each channel. More importantly, we propose two heuristic algorithms-a priority assignment algorithm based on the greedy strategy for C (WF-C) and a priority assignment algorithm based on the greedy strategy for U(WF-U)-for assigning priorities to the flows in each channel, whose time complexity is O ( m a x ( N ∗ m ∗ l o g ( m ) , ( N - m ) 2 ) ) . We then build a new simulation model to simulate the transmission of real-time flows in WirelessHART. Finally, we compare our two algorithms with WF-D and HLS algorithms in terms of the average value of the total end-to-end delay of flow sets, the ratio of schedulable flow sets, and the calculation time of the schedulability analysis. The optimal algorithm WF-C reduces the delay by up to 44.18 % and increases the schedulability ratio by up to 70.7 % , and it reduces the calculation time compared with the HLS algorithm.

13.
Acta Crystallogr D Biol Crystallogr ; 71(Pt 7): 1487-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26143920

RESUMO

Protein complexes are essential components in many cellular processes. In this study, a procedure to determine the protein-complex structure from a partial molecular-replacement (MR) solution is demonstrated using a direct-method-aided dual-space iterative phasing and model-building program suite, IPCAS (Iterative Protein Crystal structure Automatic Solution). The IPCAS iteration procedure involves (i) real-space model building and refinement, (ii) direct-method-aided reciprocal-space phase refinement and (iii) phase improvement through density modification. The procedure has been tested with four protein complexes, including two previously unknown structures. It was possible to use IPCAS to build the whole complex structure from one or less than one subunit once the molecular-replacement method was able to give a partial solution. In the most challenging case, IPCAS was able to extend to the full length starting from less than 30% of the complex structure, while conventional model-building procedures were unsuccessful.


Assuntos
Proteínas/química , Proteínas de Bactérias/química , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Escherichia coli/química , Proteínas de Escherichia coli/química , Geobacillus/química , Humanos , Klebsiella pneumoniae/química , Proteínas Ligantes de Maltose/química , Modelos Moleculares , Complexo de Proteínas Formadoras de Poros Nucleares/química , Conformação Proteica , Multimerização Proteica , Vibrio cholerae/química , beta-Lactamases/química
14.
J Eukaryot Microbiol ; 62(4): 553-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25712195

RESUMO

Enterocytozoon bieneusi is the most frequently diagnosed microsporidian species in humans. It has been found in a wide range of animals and is considered an important zoonotic pathogen. To date, little information is available on the role that cattle play in the epidemiology of human microsporidiosis caused by E. bieneusi in China. In this study, 133 fecal specimens from dairy cattle were collected in Heilongjiang Province, China. Enterocytozoon bieneusi was identified and genotyped by nested PCR analysis of the internal transcribed spacer (ITS) region of the rRNA gene, with 30.1% positive. Nine ITS genotypes were identified: six known genotypes-O (n = 26), EbpA (n = 2), I (n = 2), J (n = 2), D (n = 1) and BEB4 (n = 1)-and three novel genotypes named as CC-I to CC-III (two each). Genotype O was identified in cattle for the first time. The observation of all the six known genotypes here reported previously in humans, and also the fact of all the three novel genotypes (CHN-DC1 to CHN-DC3) falling into zoonotic group 1, indicate the possibility of cattle in the transmission of E. bieneusi to humans.


Assuntos
Doenças dos Bovinos/microbiologia , Enterocytozoon/genética , Fezes/microbiologia , Variação Genética/genética , Microsporidiose/veterinária , Animais , Bovinos , China/epidemiologia , DNA Espaçador Ribossômico/genética , Enterocytozoon/isolamento & purificação , Genótipo , Humanos , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Microsporidiose/transmissão , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Zoonoses
15.
BMC Gastroenterol ; 15: 29, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25887470

RESUMO

BACKGROUND: Cystic echinococcosis (CE) is one of emerging zoonotic parasitic diseases throughout the world, having significant medical and economic importance in developing countries. The western and northwestern China is considered as CE endemic areas. In northeastern China's Heilongjiang Province, the increasing number of sporadic human CE cases has attracted more and more attention. The aims of the present study were to understand the clinical characteristics of human CE in the investigated area and to compare the coincidence rates of CT, ultrasound and serological test against the histopathology results among CE patients. METHODS: Hospital data of 183 human CE cases in the period from January 2004 to July 2013 were collected from the two largest hospitals in Heilongjiang Province. Clinical data were analyzed, including age, gender, occupation and living residence of CE patients and localization, size and number of CE cysts as well as the diagnosis methods of CE before operation. RESULTS: The results revealed that the incidence of CE reached a peak in the age group of 41-50 years. Among the 183 CE patients, the females were observed to have a higher percentage of CE patients (60.66%, 111/183) than males (39.34%, 72/183). The majority of CE patients were farmers, followed by workers, employees, public servants, students and so on. CE cysts were most commonly found in the livers, with a 30 cm cyst in diameter being detected. CT showed the highest coincidence rate (96.64%) for hepatic CE among the three common diagnosis methods (CT, ultrasound imagine and serological test) compared against the histopathology results. CONCLUSIONS: This is the first retrospective analysis of human CE cases in Heilongjiang Province in recent ten years. Clinical characteristics of human CE were described here. CT appeared to be the most effective diagnosis method for hepatic CE.


Assuntos
Equinococose Hepática/epidemiologia , Equinococose Pulmonar/epidemiologia , Echinococcus granulosus , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Criança , China/epidemiologia , Equinococose Hepática/sangue , Equinococose Hepática/diagnóstico , Equinococose Pulmonar/sangue , Equinococose Pulmonar/diagnóstico , Echinococcus granulosus/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Incidência , Masculino , Pessoa de Meia-Idade , Ocupações , Características de Residência , Estudos Retrospectivos , Testes Sorológicos , Distribuição por Sexo , Adulto Jovem
16.
Sensors (Basel) ; 15(6): 13778-804, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26110406

RESUMO

Reducing energy consumption is becoming very important in order to keep battery life and lower overall operational costs for heterogeneous real-time multiprocessor systems. In this paper, we first formulate this as a combinatorial optimization problem. Then, a successful meta-heuristic, called Shuffled Frog Leaping Algorithm (SFLA) is proposed to reduce the energy consumption. Precocity remission and local optimal avoidance techniques are proposed to avoid the precocity and improve the solution quality. Convergence acceleration significantly reduces the search time. Experimental results show that the SFLA-based energy-aware meta-heuristic uses 30% less energy than the Ant Colony Optimization (ACO) algorithm, and 60% less energy than the Genetic Algorithm (GA) algorithm. Remarkably, the running time of the SFLA-based meta-heuristic is 20 and 200 times less than ACO and GA, respectively, for finding the optimal solution.

17.
Korean J Parasitol ; 53(6): 683-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26797434

RESUMO

Human diphyllobothriasis is a widespread fish-borne zoonosis caused by the infection with broad tapeworms belonging to the genus Diphyllobothrium. In mainland China, so far 20 human cases of Diphyllobothrium infections have been reported, and the etiologic species were identified as D. latum and D. nihonkaiense based on morphological characteristics or molecular analysis. In the present study, proglottids of diphyllobothriid tapeworms from 3 human cases that occurred in Heilongjiang Province, China were identified as D. nihonkaiense by sequencing mitochondrial cytochrome c oxidase subunit I (cox1) and NADH dehydrogenase subunit 5 (nad5) genes. Two different cox1 gene sequences were obtained. One sequence showed 100% homology with those from humans in Japan. The remaining cox1 gene sequence and 2 different nad5 gene sequences obtained were not described previously, and might reflect endemic genetic characterizations. D. nihonkaiense might also be a major causative species of human diphyllobothriasis in China. Meanwhile, the finding of the first pediatric case of D. nihonkaiense infection in China suggests that infants infected with D. nihonkaiense should not be ignored.


Assuntos
Difilobotríase/parasitologia , Diphyllobothrium/genética , Diphyllobothrium/isolamento & purificação , Adulto , Animais , China , Diphyllobothrium/classificação , Diphyllobothrium/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Proteínas de Helminto/genética , Humanos , Lactente
18.
Acta Crystallogr D Biol Crystallogr ; 70(Pt 7): 1977-82, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25004974

RESUMO

X-ray crystallography and NMR are complementary tools in structural biology. However, it is often difficult to use NMR structures as search models in molecular replacement (MR) to phase crystallographic data. In this study, a new approach is reported utilizing a molecular envelope of NMR structures for MR phasing with the program FSEARCH at low resolution (about 6 Å). Several targets with both crystallographic and NMR structures available have been tested. FSEARCH was able to find the correct translation and orientation of the search model in the crystallographic unit cell, while conventional MR procedures were unsuccessful.


Assuntos
Cristalografia por Raios X/métodos , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos
19.
Emerg Infect Dis ; 20(2): 315-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24447495

RESUMO

The cause of diphyllobothriosis in 5 persons in Harbin and Shanghai, China, during 2008-2011, initially attributed to the tapeworm Diphyllobothrium latum, was confirmed as D. nihonkaiense by using molecular analysis of expelled proglottids. The use of morphologic characteristics alone to identify this organism was inadequate and led to misidentification of the species.


Assuntos
DNA de Helmintos/genética , Difilobotríase/parasitologia , Diphyllobothrium/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Animais , China/epidemiologia , DNA de Helmintos/classificação , Difilobotríase/diagnóstico , Difilobotríase/epidemiologia , Difilobotríase/patologia , Diphyllobothrium/classificação , Diphyllobothrium/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Feminino , Humanos , Masculino , Tipagem Molecular , Filogenia , Análise de Sequência de DNA
20.
Appl Environ Microbiol ; 80(12): 3699-3707, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24727270

RESUMO

Enterocytozoon bieneusi is an emerging and clinically significant enteric parasite infecting humans and animals and can cause life-threatening diarrhea in immunocompromised people. Pigs are considered to be one of the main reservoir hosts of E. bieneusi based on their high prevalence rates and zoonotic genotypes in pigs. As an opportunistic pathogen, E. bieneusi infection of pigs can be inapparent, which leads to neglect in detecting this parasite in pigs and assessing the epidemiological role of pigs in the transmission of human microsporidiosis. In the present study, 95 healthy pigs aged 2 or 3 months were randomly selected from three areas in Heilongjiang Province, China. E. bieneusi isolates were identified and genotyped based on the small-subunit (SSU) rRNA and internal transcribed spacer (ITS) regions of the rRNA gene by PCR and sequencing. A high prevalence of E. bieneusi was observed, 83.2% (79/95) at the SSU rRNA locus versus 89.5% (85/95) at the ITS locus. Ten ITS genotypes were obtained, comprising six known genotypes­EbpA (n = 30), D (n = 19), H (n = 18), O (n = 11), CS-1 (n = 1), and LW1 (n = 1)­and four novel genotypes named HLJ-I to HLJ-IV; 70.6% (60/85) of E. bieneusi genotypes were zoonotic (genotypes EbpA, D, and O). The findings of a high prevalence of E. bieneusi in pigs and a large percentage of zoonotic genotypes indicate that pigs may play a role in the transmission of E. bieneusi to humans and may become an important source of water contamination in our investigated areas.


Assuntos
Reservatórios de Doenças/microbiologia , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Microsporidiose/microbiologia , Suínos/microbiologia , Zoonoses/microbiologia , Animais , China , Enterocytozoon/classificação , Fezes/microbiologia , Feminino , Genótipo , Humanos , Masculino , Microsporidiose/transmissão , Dados de Sequência Molecular , Filogenia , Prevalência , Zoonoses/epidemiologia
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