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1.
Development ; 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439755

RESUMO

Epithelial signaling centers control epithelial invagination and organ development, but how these centers are specified remains unclear. We report that Pitx2 (the first transcriptional marker for tooth development) controls the embryonic formation and patterning of epithelial signaling centers during incisor development. We demonstrate using Krt14 Cre /Pitx2 flox/flox (Pitx2 cKO ) embryos, and Rosa26 CreERT /Pitx2 flox/flox mice that loss of Pitx2 delays epithelial invagination, decreases progenitor cell proliferation, and dental epithelium cell differentiation. Developmentally, Pitx2 regulates formation of the Sox2+ labial cervical loop (LaCL) stem cell niche in concert with two signaling centers, the initiation knot (IK) and enamel knot (EK). The loss of Pitx2 disrupted the patterning of these two signaling centers resulting in tooth arrest at E14.5. Mechanistically, Pitx2 transcriptional activity and DNA binding is inhibited by Sox2, and this interaction controls gene expression in specific Sox2 and Pitx2 co-expression progenitor cell domains. We demonstrate new transcriptional mechanisms regulating signaling centers by Pitx2, Sox2, Lef-1 and Irx1.

3.
J Sci Food Agric ; 100(8): 3465-3470, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32170753

RESUMO

BACKGROUND: Compared with the traditional qualitative polymerase chain reaction (PCR), which only identifies the category of species, the quantitative PCR method provides a value, which is very important for appropriate penalty enforcement according to the extent of adulteration. However, most of the current quantitative PCR methods are based on mitochondrial genes, expressing different copy numbers in different cells and reducing the accuracy of quantitative results. In this study, single-copy nuclear housekeeping genes, instead of multicopy mitochondrial genes, were selected as both camel species-specific and reference genes to develop a novel normalized PCR system. RESULTS: This system had an excellent linear correlation (R2 = 0.9614) between camel milk content and Ct ratio (specific/reference genes), and allowed quantitative determination of the content of camel milk in adulterated milk samples. The accuracy was effectively validated using simulated adulterated samples with recoveries ranging from 90% to 120% and coefficient of variation less than 10%, exhibiting sufficient parameters of trueness and precision. CONCLUSIONS: The normalized PCR system based on single-copy nuclear genes is a simple, rapid and reliable method for the determination of the content of camel milk in adulterated milk samples, and also provides technical support for appropriate penalty enforcement. © 2020 Society of Chemical Industry.

4.
Acta Biomater ; 105: 223-238, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926335

RESUMO

Targeting delivery of photosensitizers to mitochondria as the most sensitive cellular organelles to reactive oxygen species (ROS) by positively charged polymeric nanocarriers (NCs) is one of the useful methods for efficient photodynamic therapy (PDT). However, the NCs with positively charged mitochondria-targeting moieties are easily cleaned during circulation, restricting their in vivo applications. Herein, to address this issue and enhance in vivo PDT efficacy, we developed a sequential-targeting delivery system consisting of mitochondria-targeting micelles as the core prepared from the cationic amphiphilic copolymer for loading chlorin e6 (Ce6) and a tumor-targeting pH-dependent charge transformational layer as the shell obtained from 2,3-dimethylmaleic anhydride modified Biotin-PEG4000-NH2 (BioPEGDMA) via electrostatic interaction. Concealed by the anionic shell, the as-prepared NCs showed longer retention within the first stage of tumor-targeting. Then, the accumulated NCs conversed to positive charge in tumor extracellular microenvironment (pH ∼ 6.5), which could be more effectively internalized by tumor cells, and the re-exposed triphenylphosphonium (TPP) groups endowed their second-stage targetability to the mitochondria. In vivo experiments revealed that the Ce6-loaded NCs exhibited remarkable tumor inhibition rates of 84.1% and 93.2% on BALB/c nude mice and Kunming mice, respectively, under 660 nm NIR irradiation, and stimulated immune responses with upregulated expression of IFN-γ, TNF-α and CD3+ in tumor tissues, and enhanced activation of CD3+/CD4+, CD3+/CD8+ T lymphocytes and DCs in both tumor tissues and lymph glands. This work provided a new pathway for the development of smart drug delivery system with advanced PDT efficacy. STATEMENT OF SIGNIFICANCE: Although the existing targeting delivery of photosensitizers to mitochondria by positively charged nanocarriers (NCs) have efficiently enhanced photodynamic therapy (PDT), their positive charges caused rapid clearance during circulation, which has restricted their in vivo applications. Therefore, we fabricated a novel sequential-targeting NC to solve the problem. The tumor accumulated NCs conversed to positive charge in tumor extracellular microenvironment, and the re-exposed triphenylphosphonium groups initiated second-stage targetability to mitochondria. This system exhibited remarkable tumor inhibition efficiency both in vitro and in vivo. Moreover, as we hypothesized, mitochondria-located PDT could promote immune response, resulting in improvement of PDT. The strategy of sequential targeting-based PDT in combination with augmented immune response showed a novel pathway for the development of smart drug delivery system with advanced PDT.

5.
Nanotechnology ; 31(20): 205201, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952059

RESUMO

We present a systematic study on the effects of CF4 plasma immersion ion implantation (PIII) in Si on the phase evolution of ultra-thin Ni silicides. For 3 nm Ni, NiSi2 was formed on Si substrates with and without CF4 PIII at temperature as low as 400 °C. For 6 nm Ni, NiSi was formed on pure Si, while epitaxial NiSi2 was obtained on CF4 PIII Si. The incorporation of C and F atoms in the thin epitaxial NiSi2 significantly reduces the layer resistivity. Increasing the Ni thickness to 8 nm results in the formation of NiSi, where the thermal stability of NiSi, the NiSi/Si interface and Schottky contacts are significantly improved with CF4 PIII. We suggest that the interface energy is lowered by the F and C dopants present in the layer and at the interface, leading to phase evolution of the thin Ni silicide.

6.
Acta Trop ; 203: 105283, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31811863

RESUMO

Echinococcosis is considered by the World Health Organization (WHO) to be a neglected zoonotic disease in the world. Some Tibetan communities were found to be highly endemic for echinococcosis just 20 years ago. Until recently, we were able to understand the overall disease burden of echinococcosis in Tibetan communities after prevalence data being available from nationwide investigations from 2012 to 2016. Data were abstracted from 9 publications regarding to echinococcosis prevalence between 2016-2018; from 10 data bases on echinococcosis prevalence for 151 Tibetan counties; and statistics of population, Gross Domestic Product (GDP) and health staff from 44 local statistic bureaus and government websites at provincial, prefecture and county level, and 2 books of provincial yearly statistics. These data were used to estimate the Disability Adjusted Life Years (DALYs) due to cystic echinococcosis (CE) and alveolar echinococcosis (AE). The distribution of DALYs was presented geographically and economically. The echinococcosis DALYs in the Tibetan communities were estimated to be 126,159 (95%UI 122,415-137,675) annually using the method recommended by WHO. AE DALYs were estimated to be 105,829 (95%UI 101,969-117,090), which were more than CE DALYs of 20,330 (95%UI 19,690-21,581). Echinococcosis affects people more in underdeveloped areas. There was a tendency that a higher echinococcosis DALYs were usually correlated a higher altitude. Health services are also poorly provided in terms of number of health staff of 5.05 per 1000 population in comparison with the national average of 5.8 per 1000 population. The data suggest that the echinococcosis burden in the center region of Qinghai-Tibet plateau is higher than that of other regions, and consequently more control and health services should be provided to the region.

7.
Sci Rep ; 9(1): 19134, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31836794

RESUMO

The abilities to fabricate wafer scale single crystalline oxide thin films on metallic substrates and to locally engineer their resistive switching characteristics not only contribute to the fundamental investigations of the resistive switching mechanism but also promote the practical applications of resistive switching devices. Here, wafer scale LiNbO3 (LNO) single crystalline thin films are fabricated on Pt/SiO2/LNO substrates by ion slicing with wafer bonding. The lattice strain of the LNO single crystalline thin films can be tuned by He implantation as indicated by XRD measurements. After He implantation, the LNO single crystalline thin films show self-rectifying filamentary resistive switching behaviors, which is interpreted by a model that the local conductive filaments only connect/disconnect with the bottom interface while the top interface maintains the Schottky contact. Thanks to the homogeneous distribution of defects in single crystalline thin films, highly reproducible and uniform self-rectifying resistive switching with large on/off ratio over four order of magnitude was achieved. Multilevel resistive switching can be obtained by varying the compliance current or by using different magnitude of writing voltage.

8.
Phys Chem Chem Phys ; 21(46): 25577-25583, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31624818

RESUMO

Laser-ablated group 6 transition metal atoms react with BF3 to yield typical transition metal inserted complexes F2B-MF (M = Cr, Mo, and W) and terminal borylene complex FB[triple bond, length as m-dash]WF2. These products are investigated by using infrared spectroscopy, isotopic substitution and theoretical frequency calculations. The inserted complexes F2B-MF (M = Cr, Mo, and W) were identified by antisymmetric and symmetric stretching modes of F-B-F. The FB[triple bond, length as m-dash]WF2 molecule has a 11B-F (10B-F) stretching frequency at 1453.2 (1505.0) cm-1 and the triple bond between boron and tungsten is confirmed by EDA-NOCV calculations, CASSCF calculation and NBO analysis. Furthermore, the bonding for tungsten complexes is compared with that of molybdenum and chromium complexes, which reveals interesting differences in their chemistries.

9.
Front Genet ; 10: 800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616463

RESUMO

The etiology of dental anomalies is multifactorial; and genetic and environmental factors that affect the dental lamina have been implicated. We investigated two families of European ancestry in which males were affected by taurodontism, microdontia and dens invaginatus. In both families, males were related to each other via unaffected females. A linkage analysis was conducted in a New Zealand family, followed by exome sequencing and focused analysis of the X-chromosome. In a US family, exome sequencing of the X-chromosome was followed by Sanger sequencing to conduct segregation analyses. We identified two independent missense variants in KIF4A that segregate in affected males and female carriers. The variant in a New Zealand family (p.Asp371His) predicts the substitution of a residue in the motor domain of the protein while the one in a US family (p.Arg771Lys) predicts the substitution of a residue in the domain that interacts with Protein Regulator of Cytokinesis 1 (PRC1). We demonstrated that the gene is expressed in the developing tooth bud during development, and that the p.Arg771Lys variant influences cell migration in an in vitro assay. These data implicate missense variations in KIF4A in a pathogenic mechanism that causes taurodontism, microdontia and dens invaginatus phenotypes.

10.
Inorg Chem ; 58(19): 13418-13425, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31549826

RESUMO

The boron-transition-metal triple-bond complexes FB≡MF2 (M= Ir, Os, Re, W, Ta) were trapped in excess solid neon and argon through metal atom reactions with boron trifluoride and identified by matrix isolation infrared spectroscopy and quantum chemical calculations. The FB≡MF2 molecule features very high 11B-F stretching frequencies at 1586.6 cm-1 (Ir), 1526.6 cm-1 (Os), 1505.5 cm-1 (Re), and 1453.2 cm-1 (W), respectively. The very high strength of B≡M bonds with triple-bonding character is confirmed by EDA-NOCV calculations and the active molecular orbital and NBO analysis. The experimental observation of FB stabilization by heavy transition-metal atoms with triple bonds opens the door to design new boron-transition-metal complexes.

11.
Anal Chem ; 91(20): 12606-12610, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31556999

RESUMO

Currently, one of important research directions of photoelectrochemical (PEC) bioanalysis is to exploit innovative photoactive species and their elegant implementations for selective detection and signal transduction. Different from existing candidates for photoelectrode development, this study, exemplified by the cationic dipeptide nanoparticles (CDNPs), reports the first demonstration of self-assembled peptide nanostructures (SAPNs) for the PEC bioanalysis. Specifically, the CDNPs were prepared as representative materials and then immobilized onto the indium tin oxide (ITO) electrode for the PEC differentiation of several commonly involved biomolecules such as ascorbic acid (AA) and l-cysteine. Significantly, the experimental results disclosed that the CDNPs possessed unique photocathodic responses and good analytical performance toward AA detection in terms of rapid response, high stability, and excellent selectivity. This work demonstrates the great potential of the large SAPN family for the future PEC bioanalysis development and has not been reported to our knowledge.

12.
Infect Dis Poverty ; 8(1): 68, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362789

RESUMO

BACKGROUND: Echinococcosis caused by Echinococcus is one of the most major infectious diseases in north-west highland of China. E. granulosus sensu strict, E. multilocularis, and E. canadensis are known to be the only three species related to human health transmitting in the areas. To achieve targeted treatment and control of echinococcosis, the accurate identification and discrimination of the species are important. However, currently the available diagnostic approaches do not present ideal results either in accuracy or efficiency. METHODS: In the study, a set of primers were designed to aim at the three human-pathogenic Echinococcus species in China. The one-step multiplex PCR assay was developed and evaluated for the specificity and sensitivity. A total of 73 parasitic lesions and 41 fecal materials obtained from human and various animals collected in the clinic and the field were tested to assess the applicability of this method. RESULTS: The multiplex PCR effectively detected the individual DNA from the targeted species and their random mixtures generating with distinguishable expected size of products. The detection limit of the assay for each of the three species was 5 pg/µl when they were tested separately. When DNA mixtures of the targeted species containing the same concentration were used as templates, the lowest amount of DNA which can be detected was 50 pg/µl, 10 pg/µl and 5 pg/µl for E. granulosus s. s., E. multilocularis, and E. canadensis respectively. No cross-reactivity was observed when DNA from eight genetically close species was used as control templates. The multiplex PCR identifications of all samples were in line with the original sequencing results except for those infected with E. shiquicus, which showed negative signals in the developed assay. Of all the tested stool materials, 16 were previously found positive for Echinococcus by visual and microscopic examination. Among these 16 samples, 13 were confirmed by the multiplex PCR, and the other three tested negative. Additionally, the multiplex PCR identified another 14 positive feces from the remained 25 stool samples which absence of worms. CONCLUSIONS: The developed multiplex PCR shows advantages in fast diagnosis and large-scale epidemiological investigation, which proven to be a promising tool utilized in clinic and surveillance system.


Assuntos
Equinococose/diagnóstico , Echinococcus/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Animais , China , Diagnóstico Diferencial , Equinococose/classificação , Equinococose/parasitologia , Echinococcus granulosus/isolamento & purificação , Echinococcus multilocularis/isolamento & purificação , Humanos
13.
Carbohydr Polym ; 223: 115142, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31427029

RESUMO

The physicochemical properties of whole wheat starch and its A-Type and B-Type granules isolated from frozen dough at 0, 4 and 8 weeks of storage were investigated. Results showed that profiles of A-Type granules were more or less constant while significant differences of B-Type granules involving in irregular edges, increased relative crystallinities and decreased Viscosities were observed after 8 weeks of storage, suggesting that B-Type granules were more sensitive to freezing. These were mainly attributed to the release of leaching materials from starches, resulting in the ratio of amylose to amylopectin, protein and lipid content decreased by 25.93%, 12.05% and 31.65%, respectively. Whole wheat starch remained essentially unchanged during freezing. It seemed that B-Type granules, as a small part of whole wheat starch, had less influence on whole wheat starch than A-type granules in spite of their significant deterioration upon storage.


Assuntos
Congelamento , Amido/química , Triticum/química , Tamanho da Partícula , Propriedades de Superfície
14.
Parasitology ; 146(12): 1595-1601, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31307567

RESUMO

Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.

15.
Phys Chem Chem Phys ; 21(28): 15639-15646, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31268441

RESUMO

We investigate the gaseous ScO(H2O)1-3Ar+ cations prepared by laser vaporization coupled with supersonic molecular beam using infrared photodissociation spectroscopy in the O-H stretching region. The cation structures are characterized by comparing the experimentally observed frequencies with the simulated vibration spectra. We reveal that stoichiometric ScO(H2O)Ar+ is intrinsically the hydrated oxide cation expressed as H2O-ScOAr+ hydrate rather than Sc(OH)2Ar+ dihydroxide, although the former is higher in energy by 29.5 kcal mol-1 than the latter. Interestingly, when more water molecules are introduced to the complex, we find that the stoichiometric ScO(H2O)2-3Ar+ embraces the core subunit of Sc(OH)2+. Theoretical calculations suggest that the energy barrier of hydrogen transfer plays a critical role in the isomerization from hydrated complex to dihydroxide. When more than one water molecule is involved in the complex, the hydrogen transfer becomes nearly barrierless through a six-member cyclic transition state, leading to the reduction in the energy barrier from 21.8 kcal mol-1 to 4.2 kcal mol-1. Altogether, we conclude that the solvent molecules such as water can decrease the energy barrier and thus induce the formation of hydroxy species in the hydrolysis process.

16.
Nat Commun ; 10(1): 2437, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164646

RESUMO

Gratings, one of the most important energy dispersive devices, are the fundamental building blocks for the majority of optical and optoelectronic systems. The grating period is the key parameter that limits the dispersion and resolution of the system. With the rapid development of large X-ray science facilities, gratings with periodicities below 50 nm are in urgent need for the development of ultrahigh-resolution X-ray spectroscopy. However, the wafer-scale fabrication of nanogratings through conventional patterning methods is difficult. Herein, we report a maskless and high-throughput method to generate wafer-scale, multilayer gratings with period in the sub-50 nm range. They are fabricated by a vacancy epitaxy process and coated with X-ray multilayers, which demonstrate extremely large angular dispersion at approximately 90 eV and 270 eV. The developed new method has great potential to produce ultrahigh line density multilayer gratings that can pave the way to cutting edge high-resolution spectroscopy and other X-ray applications.

17.
J Phys Chem A ; 123(17): 3743-3760, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30939012

RESUMO

Laser-ablated group 2 metal atoms exhibit different reactivities with (CN)2 in excess argon and neon during condensation at 4 K. UV irradiation (220-290 nm) is required to activate Be to produce the linear CNBeNC di-isocyanide molecule with a strong antisymmetric C-N stretching band at 2104.3 cm-1 and a C-N-Be-N-C stretching mode at 1265.7 cm-1. The di-isocyanide appears at lower frequency and exhibits more nitrogen and less carbon isotopic shift than the cyanide counterpart, which is confirmed by B3LYP isotopic frequency calculations. Two weak bands were observed for the cyanide NCBeCN, and three absorptions were found for the mixed ligand CNBeCN molecule, which would be difficult to synthesize and put into a bottle. Mg reacts with (CN)2 to form the CNMgNC counterpart at 2085.8 cm-1 on annealing to 25 K. Absorptions for the Ca(NC)2, Sr(NC)2, and Ba(NC)2 molecules at 2060.8, 2048.1, and 2045.9 cm-1 increase on sample annealing with these more reactive heavier alkaline earth metal atoms, which have calculated twisted bowtie side-bound (CN) structures of C2 symmetry with shorter computed M-N than M-C distances. NBO calculations for the latter molecules reveal natural charges of +1.54, 1.64, 1.71 e on the metal centers and - 0.77, 0.82, and 0.855 e on the corresponding CN subunits, with a doubly occupied sp-sp σ and two p-p π bonds on each (CN), which supports an ionic model for bonding in these molecules. A weaker band at 2056.6 cm-1 behaves nearly the same as the Ca bowtie band in the spectrum on 25 K annealing and photolysis, and it is assigned to the 6 kJ/mol higher-energy linear CNCaNC isomer. Additional similar sharp absorptions for a new Ca, Sr, and Ba reaction product at 2036.3, 2040.6, and 2036.0 cm-1 increase on annealing at the expense of adjacent broader bands: B3LYP and NBO calculations validate their assignment to ionic hexagonal C2 h (MNC)2 rings from the reaction of two M atoms with (CN)2.

18.
Head Neck ; 41(5): 1468-1474, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30633409

RESUMO

BACKGROUND: To evaluate the prognostic value of preoperative neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) in oral, pharyngeal, and lip cancer for survival and relapse. METHODS: Clinic-pathologic and hematological records were retrospectively retrieved. Patients completed follow-up period were included for survival and relapse analysis. RESULTS: The preoperative NLR value was a prognostic factor for both overall survival and relapse-free survival. The high NLR group demonstrated higher total relapse rate, higher local relapse rate, and higher relapse rate within 12 months. However, the preoperative PLR did not associate with survival or relapse. CONCLUSIONS: The preoperative NLR, not PLR, is an independent prognostic indicator of survival. It also exhibits predictive value for relapse, particularly early relapse within 12 months. The preoperative NLR value might be recommended as a useful tool for predicting the outcomes and stratifying patients for different management strategies.

19.
Inorg Chem ; 58(4): 2363-2371, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30645096

RESUMO

Laser-ablated group 3 transition metal and cerium atom reactions with boron trifluoride were explored in excess solid neon at 4 K through matrix isolation infrared spectroscopy and quantum chemical calculations. The fluoroborylene complexes FBMF2 (M = Sc, Y, La, Ce) were trapped in inert gas and identified by the isotopic substitutions. The observed frequencies of FBMF2 were reproduced by DFT, NEVPT2, and CASSCF calculations. From Sc to La, the observed F-11B stretching mode has been observed at 1391.9 cm-1 (Sc), 1370.8 cm-1 (Y), and 1337.1 cm-1(La); however, for Ce this mode shifts up to 1340.8 cm-1, which is due to relativistic effects. The electron localization function (ELF) analysis and the theory of atoms in molecules (AIM) were applied to investigate the character of the B-M bond in FBMF2 molecules, which favors bond order 1.5.

20.
Acta Trop ; 190: 45-51, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30278154

RESUMO

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are highly co-endemic in Sichuan, a part of Qinghai-Tibet Plateau where is a typical Tibetan nomadic community living area. In order to better understand the Echinococcus spp. of human being infected origins in this area, 140 lesions were collected from echinococcosis patients who were received operations during the period of 2014-2016 in different geographic districts in this region. Partial DNA sequences of the mitochondrial cox1 gene were analyzed. The genetic characterization of the isolates from 3 different places including Ganzi, Aba and Liangshan were assessed. Of all the 140 samples, the great majority was identified as Echinococcus granulosus sensu stricto (n = 108). Echinococcus multilocularis was confirmed to be another important pathogen of the human infections (n = 31). Additionally, one Echinococcus canadensis (G6/7) isolate from Ganzi was confirmed. Comparing the clinical diagnosis with the sequencing results, 6.4% (9/140) of the cases were misdiagnosed between AE and CE, and another 8.6% (12/140) were unclassified to sub-type in echinococcosis. Higher rates of misdiagnosis and unclassified diagnosis were found in AE cases (12.9%, 4/31 and 16.1%, 5/31 respectively) compared to CE (4.6%, 5/109 and 6.4%, 7/109 respectively). In E.granulosus s.s., a total of 34 haplotypes were detected, and 4 haplotypes were inferred from E.multilocularis. The haplotype networks of the 2 species exhibited a similar star-shaped feature with a dominant haplotype in the center. Geographically specific haplotypes were observed in Ganzi and Aba respectively. This study provides insight into the current species causing human echinococcosis in the Tibetan districts of Sichuan. E.granulosus s.s. and E.multilocularis are confirmed to be the main causative agents, and the existence of E.canadensis (G6/7) is also observed in the region. Molecular diagnosis was proven to be essential for the confirmation of human echinococcosis in the area.


Assuntos
Echinococcus granulosus/genética , Echinococcus multilocularis/genética , Adulto , Idoso , Animais , Equinococose/parasitologia , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade
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