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1.
Br J Clin Pharmacol ; 90(5): 1213-1221, 2024 May.
Article in English | MEDLINE | ID: mdl-38317382

ABSTRACT

AIMS: Levofloxacin is a quinolone antibiotic with a broad antibacterial spectrum. It is frequently used in elderly patients with pneumonia. The pharmacokinetic profile of elderly patients changes with age, but data on the pharmacokinetics of levofloxacin in these patients are limited. The aim of this study was to establish a population pharmacokinetic model of levofloxacin in elderly patients with pneumonia and to optimize individualized dosing regimens based on this newly developed model. METHODS: This is a prospective, open-label pharmacokinetic study in elderly patients with pneumonia. Blood samples were collected using an opportunistic approach. The plasma concentrations of levofloxacin were determined by high-performance liquid chromatography. A population pharmacokinetic model was established using nonlinear mixed-effect model software. Monte Carlo simulations were used for dose simulation and dose optimization. RESULTS: Data from 51 elderly patients with pneumonia were used for the population pharmacokinetic analysis. A one-compartment model with first-order elimination was most suitable for describing the data, and the estimated glomerular filtration rate was the only covariate that had a significant impact on the model. The final model estimated that the mean clearance of levofloxacin in elderly patients with pneumonia was 5.26 L/h. Monte Carlo simulation results showed that the optimal dosing regimen for levofloxacin was 750 mg once a day in elderly patients with pneumonia, with a minimum inhibitory concentration of 2 mg/L. CONCLUSIONS: The population pharmacokinetic model of levofloxacin in elderly patients with pneumonia was established, and the dose optimization of levofloxacin was completed through Monte Carlo simulation.


Subject(s)
Anti-Bacterial Agents , Levofloxacin , Models, Biological , Monte Carlo Method , Pneumonia , Humans , Levofloxacin/pharmacokinetics , Levofloxacin/administration & dosage , Levofloxacin/blood , Aged , Male , Anti-Bacterial Agents/pharmacokinetics , Anti-Bacterial Agents/administration & dosage , Female , Aged, 80 and over , Prospective Studies , Pneumonia/drug therapy , Dose-Response Relationship, Drug , Glomerular Filtration Rate , Computer Simulation
2.
J Am Chem Soc ; 145(37): 20646-20654, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37695885

ABSTRACT

Chiral organosilanes are valuable chemical entities in the development of functional organic materials, asymmetric catalysis, and medicinal chemistry. As an important strategy for constructing chiral organosilanes, the asymmetric functionalization of the Si-CAryl bond typically relies on transition-metal catalysis. Herein, we present an efficient method for atroposelective synthesis of biaryl siloxane atropisomers via organocatalytic Si-C bond functionalization of dinaphthosiloles with silanol nucleophiles. The reaction proceeds through an asymmetric protonation and simultaneous Si-C bond cleavage/silanolysis sequence in the presence of a newly developed chiral Brønsted acid catalyst. The versatile nature of the Si-C bond streamlines the derivatization of axially chiral products into other functional atropisomers, thereby expanding the applicability of this method.

3.
Int J Biometeorol ; 67(10): 1629-1641, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37535117

ABSTRACT

The impact of weather variability and air pollutants on tuberculosis (TB) has been a research hotspot. Previous studies have mostly been limited to a certain area or with a small sample size of cases, and multi-scale systematic studies are lacking. In this study, 14,816,329 TB cases were collected from 31 provinces in China between 2004 and 2018 to estimate the association between TB risk and meteorological factors and air pollutants using a two-stage time-series analysis. The impact and lagged time of meteorological factors and air pollutants on TB risk varied greatly in different provinces and regions. Overall cumulative exposure-response summary associations across 31 provinces suggested that high monthly mean relative humidity (RH) (66.8-82.4%, percentile56-100 (P56-100)), rainfall (316.5-331.1 mm, P96-100), PM2.5 exposure concentration (93.3-145.0 µg/m3, P58-100), and low monthly mean wind speed (1.6-2.1 m/s, P0-38) increased the risk of TB incidence, with a relative risk (RR) of 1.10 (95% CI: 1.04-1.16), 1.10 (95% CI: 1.03-1.16), 2.08 (95% CI: 1.18-3.65), and 2.06 (95% CI: 1.27-3.33), and attributable risk percent (AR%) of 9%, 9%, 52%, and 51%, respectively. Conversely, high monthly average wind speed (2.3-2.9 m/s, P54-100) and mean temperature (20.2-25.3 °C, P79-96), and low monthly average rainfall (2.4-25.2 mm, P0-7) and concentration of SO2 (8.1-21.2 µg/m3, P0-16) exposure decreased the risk of TB incidence, with an overall cumulative RR of 0.92 (95% CI: 0.87-0.98), 0.74 (95% CI: 0.59-0.94), 0.87 (95% CI: 0.79-0.95), and 0.72 (95% CI: 0.56-0.93), respectively. Our study provided insights into future planning of public health interventions for TB.


Subject(s)
Air Pollutants , Air Pollution , Tuberculosis , Humans , Air Pollutants/analysis , Air Pollution/analysis , Tuberculosis/epidemiology , Tuberculosis/etiology , Meteorological Concepts , China/epidemiology , Risk Factors , Particulate Matter/analysis
4.
Angew Chem Int Ed Engl ; 62(3): e202215820, 2023 Jan 16.
Article in English | MEDLINE | ID: mdl-36424372

ABSTRACT

A Cu/CPA co-catalytic system has been developed for achieving the direct hydrophosphinylation of alkynes with phosphine oxides in delivering novel axially chiral phosphorus-containing alkenes in high yields and excellent enantioselectivities (up to 99 % yield and 99 % ee). DFT calculations were performed to elucidate the reaction pathway and the origin of enantiocontrol. This streamlined and modular methodology establishes a new platform for the design and application of new axially chiral styrene-phosphine ligands.

5.
Angew Chem Int Ed Engl ; 62(25): e202303128, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37186009

ABSTRACT

Atroposelective cross-coupling is one of the most appealing routes to construct axially chiral binaphthyl molecules due to the modular and succinct nature. Although transition-metal-catalyzed cross-couplings offer reliable synthetic means, alternative reaction modes that could be applied to broader substrate range without their pre-functionalization is highly desirable. Herein we show that the application of chiral Brønsted acid catalyst as organocatalyst could accomplish cross-coupling of 1-azonaphthalenes and 2-naphthols with high efficiency, exclusive C4-selectivity as well as excellent enantioselectivity and functional group compatibility. The identification of acylimidazolinone auxiliary for azo activating group, effective remote catalyst control and arene resonance effect synergistically play key roles in the development of this method. The utility is further demonstrated by transformations of the products into other binaphthyl compounds with perfectly retained axial chirality.


Subject(s)
Acids , Naphthols , Naphthols/chemistry , Catalysis , Stereoisomerism
6.
Angew Chem Int Ed Engl ; 61(45): e202211211, 2022 11 07.
Article in English | MEDLINE | ID: mdl-36111538

ABSTRACT

The application of Suzuki-Miyaura coupling reaction to forge the atropisomeric biaryls has seen remarkable progress but exploration of this chemistry to directly forge chiral C(aryl)-C(alkene) axis is underdeveloped. The replacement of arene substrates by alkenes intensifies the challenges in terms of reactivity, configurational atropostability of product and selectivity control. By meticulous ligand design and fine-tuning of reaction parameters, we identified a highly active 3,3'-triphenylsilyl-substituted phosphite ligand to realize arene-alkene Suzuki-Miyaura coupling of hindered aryl halides and vinyl boronates under very mild conditions. The axially chiral acyclic aryl-alkenes were generated in commendable efficiency, enantioselectivity and E/Z selectivity.


Subject(s)
Alkenes , Palladium , Ligands , Catalysis
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 662-670, 2021 Jul.
Article in Zh | MEDLINE | ID: mdl-34323047

ABSTRACT

OBJECTIVE: To analyze the prevalence of diabetes mellitus among middle-aged and older rural adults of Xinxiang county, Henan Province and its correlation with dietary patterns. METHODS: The study was done based on the data collected from a cross-sectional survey of Xinxiang County, which was part of the Prospective Cohort Study on the Common Chronic Non-Communicable Diseases in Rural areas of Henan Province. Randomized cluster sampling was used to select adult respondents (≥18 years old) from among the residents of 17 villages in Xinxiang county. The respondents completed questionnaires, and underwent physical examinations and laboratory tests between April, 2017 and June, 2017. A total of 7604 individuals aged between 45 and 79 were included in our study. Dietary patterns were established through factor analysis and the dietary pattern factor scores were divided into quartiles (Q1-Q4). The relationship between dietary patterns and diabetes mellitus was analyzed with multivariate logistic regression model. RESULTS: Out of the total of 7604 middle-aged and older rural adults in Xinxiang County, Henan Province, 1604 had diabetes mellitus, suggesting a 21.1% prevalence of diabetes mellitus. Factor analysis was used to establish four dietary patterns, namely animal-based diet, vegetable-egg diet, mixed diet and traditional diet. Subjects of these four dietary patterns displayed different demographic characteristics. There were no statistical difference in anthropometricor clinical indicators between the quartile with the lowest dietary pattern factor score (Q1) and the quartile with the highest dietary pattern factor score (Q4) for subjects with animal-based diet ( P>0.05). Compared with those in the Q1 quartile of vegetable-egg diet, subjects in the Q4 quartile of vegetable-egg diet showed lower levels of high-density lipoprotein cholesterol (HDL-C), along with different distribution of fasting blood glucose (FBG), showing statistically significant difference ( P<0.05). In comparison to subjects in Q1 quartile of mixed diet, those in Q4 quartile showed lower levels of systolic blood pressure (SBP), the difference being statistically significant ( P<0.05). In the traditional diet group, subjects in the Q4 quartile had lower waist circumference (WC), but higher levels of HDL-C than those of subjects in Q1 quartile. In addition, the distribution of glycated-hemoglobin (HbA1c) and FBG were different, the difference being statistically significant ( P<0.05). The results of multivariate logistic regression analysis demonstrated that traditional diet could be a protective factor of diabetes mellitus (odds ratio [ OR]=0.810, 95% CI: 0.690-0.952, P trend<0.05) after adjusting for multiple confounding factors. CONCLUSION: The prevalence of diabetes in middle-aged and older rural residents is relatively high in Xinxiang County, Henan Province, and there may be a protective relationship between traditional diet and diabetes mellitus.


Subject(s)
Diabetes Mellitus , Rural Population , Adolescent , Adult , Aged , Animals , China/epidemiology , Cross-Sectional Studies , Diabetes Mellitus/epidemiology , Diet , Humans , Middle Aged , Prospective Studies , Risk Factors
8.
Angew Chem Int Ed Engl ; 60(47): 24888-24893, 2021 11 15.
Article in English | MEDLINE | ID: mdl-34553823

ABSTRACT

Described herein is an imidazole ring formation strategy for the synthesis of axially chiral N-arylbenzimidazoles by means of chiral phosphoric acid catalysis. Two sets of conditions were developed to transform two classes of 2-naphthylamine derivatives into structurally diverse N-arylbenzimidazole atropisomers with excellent chemo- and regioselectivity as well as high levels of enantiocontrol. It is worth reflecting on the unique roles played by the nitroso group in this domino reaction. It functions as a linchpin by first offering an electrophilic site (N) for the initial C-N bond formation while the resulting amine performs the nucleophilic addition to form the second C-N bond. Additionally, it could facilitate the final oxidative aromatization as an oxidant. The atropisomeric products could be conveniently elaborated to a series of axially chiral derivatives, enabling the exploitation of N-arylbenzimidazoles for their potential utilities in asymmetric catalysis.

9.
Acta Pharmacol Sin ; 41(11): 1457-1464, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32424239

ABSTRACT

Mitsugumin 53 (MG53) is a tripartite motif family protein that has been reported to attenuate injury via membrane repair in different organs. Contrast-induced acute kidney injury (CI-AKI) is a common complication caused by the administration of iodinated contrast media (CM). While the cytotoxicity induced by CM leading to tubular cell death may be initiated by cell membrane damage, we wondered whether MG53 alleviates CI-AKI. This study was designed to investigate the effect of MG53 on CI-AKI and the underlying mechanism. A rat model of CI-AKI was established, and CI-AKI induced the translocation of MG53 from serum to injury sites on the renal proximal tubular (RPT) epithelia, as illustrated by immunoblot analysis and immunohistochemical staining. Moreover, pretreatment of rats with recombinant human MG53 protein (rhMG53, 2 mg/mL) alleviated iopromide-induced injury in the kidney, which was determined by measuring serum creatinine, blood urea nitrogen and renal histological changes. In vitro studies demonstrated that exposure of RPT cells to iopromide (20, 40, and 80 mg/mL) caused cell membrane injury and cell death, which were attenuated by rhMG53 (10 and 50 µg/mL). Mechanistically, MG53 translocated to the injury site on RPT cells and bound to phosphatidylserine to protect RPT cells from iopromide-induced injury. In conclusion, MG53 protects against CI-AKI through cell membrane repair and reducing cell apoptosis; therefore, rhMG53 might be a potential effective means to treat or prevent CI-AKI.


Subject(s)
Acute Kidney Injury/prevention & control , Apoptosis/drug effects , Cell Membrane/drug effects , Protective Agents/therapeutic use , Tripartite Motif Proteins/therapeutic use , Acute Kidney Injury/chemically induced , Acute Kidney Injury/pathology , Animals , Cell Membrane/metabolism , Epithelial Cells , Female , Humans , Iohexol/analogs & derivatives , Kidney/pathology , Kidney Tubules, Proximal/cytology , Male , Phosphatidylserines/metabolism , Protective Agents/metabolism , Rats, Inbred WKY , Rats, Sprague-Dawley , Recombinant Proteins/metabolism , Recombinant Proteins/therapeutic use , Tripartite Motif Proteins/metabolism
10.
Angew Chem Int Ed Engl ; 59(17): 6775-6779, 2020 Apr 20.
Article in English | MEDLINE | ID: mdl-32017378

ABSTRACT

N-arylcarbazole structures are important because of their prevalence in natural products and functional OLED materials. C-H amination of arenes has been widely recognized as the most efficient approach to access these structures. Conventional strategies involving transition-metal catalysts suffer from confined substrate generality and the requirement of exogenous oxidants. Organocatalytic enantioselective C-N chiral axis construction remains elusive. Presented here is the first organocatalytic strategy for the synthesis of novel axially chiral N-arylcarbazole frameworks by the assembly of azonaphthalenes and carbazoles. This reaction accommodates broad substrate scope and gives atropisomeric N-arylcarbazoles in good yields with excellent enantiocontrol. This approach not only offers an alternative to metal-catalyzed C-N cross-coupling, but also brings about opportunities for the exploitation of structurally diverse N-aryl atropisomers and OLED materials.

11.
Angew Chem Int Ed Engl ; 59(51): 23077-23082, 2020 12 14.
Article in English | MEDLINE | ID: mdl-32886439

ABSTRACT

An organocatalytic atroposelective strategy for accessing enantioenriched axially chiral IAN analogues was developed for the first time. A class of novel atropisomeric C2-arylquinoline skeletons were synthesized with high enantiocontrol via chiral phosphoric-acid-catalyzed heteroannulation of in situ generated vinylidene ortho-quinone methide (VQM) intermediates with ortho-aminophenones. The strategy tolerated a broad substrate scope, providing a facile organocatalytic approach to IAN analogues in good yields and excellent enantioselectivities under mild reaction conditions. Moreover, the synthetic utility of this methodology was illustrated through further transformations into IAN-type ligand and axially chiral thiourea.

12.
Acc Chem Res ; 51(2): 534-547, 2018 02 20.
Article in English | MEDLINE | ID: mdl-29419282

ABSTRACT

Axially chiral compounds have received much attention from chemists because of their widespread appearance in natural products, biologically active compounds, and useful chiral ligands in asymmetric catalysis. Because of the importance of this structural motif, the catalytic enantioselective construction of axially chiral scaffolds has been intensively investigated, and great progress has been accomplished. However, the majority of methodologies in this field focus on the use of metal catalysis, whereas approaches involving organocatalysis have started to emerge only recently. This Account describes certain advances in the organocatalytic asymmetric synthesis of axially chiral compounds involving the following strategies: kinetic resolution, desymmetrization, cyclization/addition, direct arylation, and so on. We began our investigation by developing a highly efficient strategy for the kinetic resolution of axially chiral BINAM derivatives involving a chiral Brønsted acid-catalyzed imine formation and transfer hydrogenation cascade process, thereby providing a convenient route to generate chiral BINAM derivatives in high yields with excellent enantioselectivities. The desymmetrization of 1-aryltriazodiones (ATADs) through an organocatalyzed tyrosine clicklike reaction wherein a nucleophile was added to the ATAD afforded an interesting type of axially chiral N-arylurazole in an excellent remote enantiocontrolled manner. We then focused on a direct construction strategy involving cyclization and the addition strategy given the inherent limitations of the kinetic resolution in terms of the chemical yield and the desymmetrization in terms of the substrate scope. By utilizing the catalytic enantioselective Paal-Knorr reaction, we disclosed a general and efficient cyclization method to access enantiomerically pure arylpyrroles. The direct heterocycle formation and the stepwise method, which was executed in a one-pot fashion containing enantioselective cyclization and subsequent aromatization, were successfully applied for the construction of diverse axially chiral arylquinazolinones catalyzed by chiral Brønsted acids. We discovered the asymmetric organocatalytic approach to construct axially chiral styrenes through the 1,4-addition of arylalkynals in good chemical yields and enantioselectivities. Such structural motifs are important precursors for further transformations into biologically active compounds and useful synthetic intermediates and may have potential applications in asymmetric syntheses as olefin ligands or organocatalysts. To further tackle this challenge, we accomplished the phosphoric acid-catalyzed enantioselective direct arylative reactions of 2-naphthol and 2-naphthamine with quinone derivatives to deliver efficient access to a class of axially chiral BINOL and NOBIN derivatives in good yields with excellent enantioselectivities under mild reaction conditions. Most importantly, we discovered that the azo group can effectively perform as a directing and activating group for organocatalytic formal aryl C-H functionalization via formal nucleophilic aromatic substitution of azobenzene derivatives. Thus, a wide range of axially chiral arylindoles were synthesized in good yields with excellent enantioselectivities. We anticipate that this strategy will foster the development of many other transformations and motivate a new enthusiasm for organocatalytic enantioselective aryl functionalization. Moreover, SPINOLs are fundamental synthetic precursors in the construction of other chiral organocatalysts and ligands. We have successfully developed a phosphoric acid-catalyzed enantioselective approach for SPINOLs. This approach is highly convergent and functional-group-tolerant for the efficient generation of SPINOLs with good results, thus delivering practical access to this privileged structure.

13.
Angew Chem Int Ed Engl ; 58(38): 13443-13447, 2019 Sep 16.
Article in English | MEDLINE | ID: mdl-31338946

ABSTRACT

Axially chiral 2-arylpyrrole frameworks are efficiently accessed through a direct chirality transfer strategy by rapid cyclization of enantioenriched atropisomeric alkenes, which are generated by organocatalytic asymmetric N-alkylation reactions. This approach accommodates a broad scope of substrates with remarkably high chirality transfer efficiency, affording novel atropisomers with a fully substituted pyrrole moiety and high enantiopurities. Given the enantioenriched atropisomeric alkenes, novel heterocyclic 2-arylazepine atropisomers were realized through a rationally designed ene reaction.

14.
Cell Mol Biol Lett ; 22: 22, 2017.
Article in English | MEDLINE | ID: mdl-29118814

ABSTRACT

BACKGROUND: TGF-ß1 plays an important role in the epithelial-mesenchymal transition (EMT) of epithelial cancers, including non-small cell lung cancer (NSCLC). While the full underlying mechanism remains unclear, miR-9 is known to play a critical role in the regulation of NSCLC cell invasion. We tested whether miR-9 targets E-cadherin and thus affects TGF-ß1-induced EMT in NSCLC cells by assessing the expression levels of miR-9 and E-cadherin for NSCLC patients and then verifying the targeting of E-cadherin by miR-9 using the dual luciferase reporter system. RESULTS: MiR-9 was significantly upregulated in NSCLC tissues compared with its level in adjacent normal tissues. The expression of E-cadherin in NSCLC tissues was significantly decreased. In addition, we found that TGF-ß1 significantly upregulated the expression of miR-9 and downregulated the expression of E-cadherin. E-cadherin was confirmed as a direct target gene of miR-9. Using an miR-9 inhibitor reversed the TGF-ß1-mediated inhibition of E-cadherin expression and upregulation of the mesenchymal marker α-SMA. TGF-ß1 significantly induced cell invasion, and this effect was significantly inhibited by miR-9 inhibitors. CONCLUSIONS: TGF-ß1 induced EMT in NSCLC cells by upregulating miR-9 and downregulating miR-9's target, E-cadherin.


Subject(s)
Cadherins/genetics , Down-Regulation/drug effects , Epithelial-Mesenchymal Transition/genetics , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Transforming Growth Factor beta1/pharmacology , Up-Regulation/drug effects , Base Sequence , Cadherins/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Epithelial-Mesenchymal Transition/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , HEK293 Cells , Humans , Male , MicroRNAs/genetics , MicroRNAs/metabolism , Middle Aged
15.
Korean J Parasitol ; 54(4): 407-14, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27658591

ABSTRACT

Malaria remains a serious public health problem in Shandong Province, China; therefore, it is important to explore the characteristics of the current malaria prevalence situation in the province. In this study, data of malaria cases reported in Shandong during 2012-2014 were analyzed, and Plasmodium species were confirmed by smear microscopy and nested-PCR. A total of 374 malaria cases were reported, 80.8% of which were reported from 6 prefectures. Of all cases, P. falciparum was dominant (81.3%), followed by P. vivax (11.8%); P. ovale and P. malariae together accounted for 6.4% of cases. Notably, for the first time since 2012, no indigenous case had been reported in Shandong Province, a situation that continued through 2014. Total 95.2% of cases were imported from Africa. The ratio of male/female was 92.5:1, and 96.8% of cases occurred in people 20-54 years of age. Farmers or laborers represented 77.5% of cases. No significant trends of monthly pattern were found in the reported cases. All patients were in good condition after treatment, except for 3 who died. These results indicate that imported malaria has increased significantly since 2012 in Shandong Province, especially for P. falciparum, and there is an emergence of species diversity.


Subject(s)
Malaria/epidemiology , Malaria/parasitology , Plasmodium/classification , Plasmodium/isolation & purification , Travel , Adolescent , Adult , Africa , Age Distribution , Child, Preschool , China/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Microscopy , Middle Aged , Polymerase Chain Reaction , Sex Distribution , Young Adult
16.
Article in Zh | MEDLINE | ID: mdl-30141587

ABSTRACT

Objective: To investigate the mutation of genes associated with drug resistance (Pfcrt, Pfmdr1, Pfdhfr and K13) in imported Plasmodium falciparum in Shandong Province. Methods: Blood was collected from 94 falciparum malaria cases who returned from Africa in 2014. Genomic DNA for P. falciparum was extracted from the blood samples and nested PCR was performed using primers specifically designed for Pfcrt, Pfmdr1, Pfdhfr and K13. The PCR products were sequenced. Gene mutations were analyzed by sequence alignment. Results: The 94 imported cases were from 18 African countries. Nested PCR was successful on DNA from all the blood samples except for Pfcrt amplification in one sample. Sequence analysis revealed three types of mutations Pfcrt K76T (36.6%, 34/93), Pfmdr1 N86Y (21.3%, 20/94), and Pfdhfr S108N (98.9%, 93/94) (χ2=127.5, P<0.05). K13 C580Y mutation was not found. Co-occurrence of K76T, N86Y, and S108N was found in 6 blood samples (6.5%), which were imported from Liberia(2), Angola(1), Equatorial guinea(1), Congo(1), and Guinea(1). Co-occurrence of K76T and S108N mutations was found in 28 samples(30.1%), and that of N86Y and S108N in 14 samples (15.1%). Forty-four samples(47.3%) harbored S108N mutation only, and one sample was null for any of the mutations. Conclusion: There are mutations in Pfcrt, Pfmdr1, and Pfdhfr in imported Plasmodium falciparum in Shandong Province. No mutation was found for the K13 gene.


Subject(s)
Plasmodium falciparum , Africa , Antimalarials , Chloroquine , DNA Primers , Drug Resistance , Malaria, Falciparum , Membrane Transport Proteins , Mutation , Polymerase Chain Reaction , Protozoan Proteins
17.
Article in Zh | MEDLINE | ID: mdl-26080528

ABSTRACT

OBJECTIVE: To identity Plasmodium ovale infection by 18S rRNA gene nested PCR. METHODS: Whole blood and filter paper blood samples of malaria patients in Shandong Province were collected during 2012-2013. The parasites were observed under a microscope with Giemsa staining. The genome DNA of blood samples were extracted as PCR templates. Genus- and species-specific primers were designed according to the Plasmodium 18S rRNA gene sequences. Plasmodium ovale-positive specimens were identified by nested PCR as well as verified by sequencing. RESULTS: There were 7 imported cases of P. ovale infection in the province during 2012-2013. Nested PCR results showed that the P. ovale specific band (800 bp) was amplified in all the 7 specimens. Blast results indicated that the PCR products were consistent with the Plasmodium ovale reference sequence in GenBank. CONCLUSION: Seven imported cases of ovale malaria in Shandong Province in 2012-2013 are confirmed by nested PCR.


Subject(s)
Malaria/diagnosis , Plasmodium ovale , Polymerase Chain Reaction/methods , DNA Primers , DNA, Protozoan/genetics , Humans , RNA, Ribosomal, 18S/genetics , Species Specificity
18.
Malar J ; 13: 379, 2014 Sep 23.
Article in English | MEDLINE | ID: mdl-25245258

ABSTRACT

BACKGROUND: Anopheles sinensis is one of the most important malaria vectors in China and other Southeast Asian countries. High levels of resistance have been reported in this species due to the long-term use of insecticides, especially pyrethroids, for public health and agricultural purposes. Knockdown resistance (kdr) caused by a single base pair mutation in the gene encoding the sodium channel is strongly associated with pyrethroid insecticide resistance in many Anopheles mosquitoes. There are few methods currently available for detecting kdr mutations in An. sinensis. METHODS: A novel AllGlo probe-based qPCR (AllGlo-qPCR) method was developed to screen for the predominant kdr mutations in An. sinensis mosquitoes from the Jiangsu Province. The results from AllGlo-qPCR, allele-specific PCR (AS-PCR), and TaqMan-MGB probe-based qPCR (TaqMan-qPCR) were compared. A comparative analysis of the equipment required, ease of use and cost of the available methods was also performed. Finally, the AllGlo-qPCR method was used to detect the frequencies of kdr mutations from the other four provinces in central China. RESULTS: Six kdr genotypes were detected in An. sinensis from the Jiangsu Province by DNA sequencing. The AllGlo-qPCR method detected all of the kdr genotypes with a high level of accuracy (97% sensitivity and 98% specificity). AllGlo-qPCR correctly determined the kdr genotypes of 98.73% of 158 An. sinensis samples, whereas TaqMan-qPCR and AS-PCR correctly identified 96.84% and 88.61% of mutations, respectively. Furthermore, the AllGlo-qPCR method is simpler to perform, requires less equipment, and exhibits a moderate expense cost comparing with the other tested methods of kdr mutation detection. Samples collected from four of the other provinces in central China showed a high frequency of kdr mutation in An. sinensis, as detected by the established AllGlo-qPCR method. CONCLUSION: The novel AllGlo-qPCR method developed for kdr mutation detection in An. sinensis exhibits greater specificity and sensitivity than currently available methods and is more cost-effective; therefore, it represents a useful tool for entomological surveillance.


Subject(s)
Anopheles/drug effects , Anopheles/genetics , Insecticide Resistance/genetics , Molecular Probe Techniques , Polymerase Chain Reaction/methods , Animals , Base Sequence , China , Genotype , Molecular Sequence Data , Mutation , Sensitivity and Specificity
19.
Zoolog Sci ; 31(8): 529-34, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25088594

ABSTRACT

Characterization of foraging-site preferences of threatened and endangered species is a key component of effective habitat conservation. We studied foraging-site selection by the brown eared pheasant (Crossoptilon mantchuricum) in the Huanglongshan Nature Reserve, Yanan City, Shaanxi Province, China, from early February to end of May 2011. We identified feeding sites by locating tracks and scratches characteristic of the birds, and compared habitat characteristics at these sites to those at randomly selected sites across the study area. During the pre-breeding season, the birds tended to be found in the areas characterized by gullies within mixed forests with intermediate sun exposure on gentle slopes (< 10°), and close to water and footpaths. The sites utilized by the birds also featured greater tree diameter, lower shrub density, lower grass cover, and lower altitude than random sites. During the breeding season, the birds tended to be found in the areas of slightly higher altitude, more shrubs, moderately steep slopes (10°-20°), and farther from water and paths. These patterns were consistent with seasonal changes in vegetation and food-resource availability in the study area. Management of brown eared pheasants' populations for conservation must account for these seasonal shifts in habitat requirements.


Subject(s)
Ecosystem , Galliformes/physiology , Seasons , Animals , China , Demography , Reproduction/physiology
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