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1.
Clin Radiol ; 79(1): e147-e155, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37884401

RESUMO

AIM: To explore the value of 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT)-based radiomics model for predicting the degree of pathological differentiation in non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: Clinical characteristics of 182 NSCLC patients from four centres were collected, and radiomics features were extracted from 18F-FDG PET/CT images. Three logistic regression prediction models were established: clinical model; radiomics model; and nomogram combining radiomics signatures and clinical features. The predictive ability of the models was assessed using receiver operating characteristics curve analysis. RESULTS: Patients from centre 1 were assigned randomly to the training and internal validation cohorts (7:3 ratio); patients from centres 2-4 served as the external validation cohort. The area under the curve (AUC) values for the clinical model in the training, internal validation, and external validation cohort were 0.74 (95% confidence interval [CI] = 0.64-0.84), 0.64 (95% CI = 0.46-0.81), and 0.74 (95% CI = 0.60-0.88), respectively. In the training (AUC: 0.84 [95% CI = 0.77-0.92]), internal validation (AUC: 0.81 [95% CI = 0.67-0.95]), and external validation cohorts (AUC: 0.74 [95% CI = 0.58-0.89]), the radiomics model showed good predictive ability for differentiation. Compared to the clinical and radiomics models, the nomogram has relatively better diagnostic performance, and the AUC values for nomogram in the training, internal validation, and external validation cohort were 0.86 (95% CI = 0.78-0.93), 0.83 (95% CI = 0.70-0.96), and 0.77 (95% CI = 0.62-0.92), respectively. CONCLUSIONS: The 18F-FDG PET/CT-based radiomics model showed good ability for predicting the degree of differentiation of NSCLC. The nomogram combining the radiomics signature and clinical features has relatively better diagnostic performance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Nomogramas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiômica , Estudos Retrospectivos
2.
Clin Radiol ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38749827

RESUMO

PURPOSE: To compare the image quality and pulmonary nodule detectability between deep learning image reconstruction (DLIR) and adaptive statistical iterative reconstruction-Veo (ASIR-V) in ultra-low-dose CT (ULD-CT). METHODS: 142 participants required lung examination who underwent simultaneously ULD-CT (UL-A, 0.57 ± 0.04 mSv or UL-B, 0.33 ± 0.03 mSv), and standard CT (SDCT, 4.32 ± 0.33 mSv) plain scans were included in this prospective study. SDCT was the reference standard using ASIR-V at 50% strength (50%ASIR-V). ULD-CT was reconstructed with 50%ASIR-V, DLIR at medium and high strength (DLIR-M, DLIR-H). The noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and subjective scores were measured. The presence and accuracy of nodules were analyzed using a combination of a deep learning-based nodule evaluation system and a radiologist. RESULTS: A total of 710 nodules were detected by SDCT, including 358 nodules in UL-A and 352 nodules in UL-B. DLIR-H exhibited superior noise, SNR, and CNR performance, and achieved comparable or even higher subjective scores compared to 50%ASIR-V in ULD-CT. Nodules sensitivity detection of 50%ASIR-V, DLIR-M, and DLIR-H in ULD-CT were identical (96.90%). In multivariate analysis, body mass index (BMI), nodule diameter, and type were independent predictors for the sensitivity of nodule detection (p<.001). DLIR-H provided a lower absolute percent error (APE) in volume (3.10% ± 95.11% vs 8.29% ± 99.14%) compared to 50%ASIR-V of ULD-CT (P<.001). CONCLUSIONS: ULD-CT scanning has a high sensitivity for detecting pulmonary nodules. Compared with ASIR-V, DLIR can significantly reduce image noise, and improve image quality, and accuracy of the nodule measurement in ULD-CT.

3.
Zhonghua Zhong Liu Za Zhi ; 43(1): 108-112, 2021 Jan 23.
Artigo em Zh | MEDLINE | ID: mdl-33472322

RESUMO

Objective: To estimate the incidence and mortality of corpus uteri cancer in China, 2015. Methods: Quality audit and evaluation of the data from 2015 cancer registration reported by 501 cancer registries were conducted, and 368 cancer registries were included in the analysis. The incidence rate and mortality rate of corpus uteri cancer were calculated according to the factors of the region (urban, rural, east, central, western), sex and age groups. The incidence and mortality of corpus uteri cancer with the 2015 population were estimated. Chinese standard population in 2000 and world Segi's population were used for the calculation of age-standardized rates (ASR) of incidence and mortality. Results: In 2015, 368 cancer registries included in the analysis covered a total of 309 553 499 populations in China, accounting for 22.52% of the national population. It is estimated that there were about 68 900 new cases of corpus uteri cancer in 2015, the incidence rate was 10.28/10(5), age-standardized incidence rates by Chinese standard population (ASR China) and world standard population (ASR world) were 6.86/10(5) and 6.66/10(5), respectively. The incidence rate of urban area (11.35/10(5)) was higher than that of rural area (8.90/10(5)), and the incidence of eastern region (12.12/10(5)) was higher than the central region (9.94/10(5)) and the western region (8.25/10(5)). It is estimated that in 2015, there were about 16 000 deaths of corpus uteri cancer, the mortality rate was 2.39/10(5), ASR China was 1.49/10(5), ASR world was 1.47/10(5). The mortality in urban areas (2.40/10(5)) is close to rural areas (2.39/10(5)); the mortality in central areas (2.55/10(5)) was higher than the eastern areas (2.32/10(5)) and the western areas (2.31/10(5)). Conclusions: In China, the incidence of corpus uteri cancer is on the rise and has a trend of youth, the burden of disease is gradually increasing, which threatens the health of women. Targeted prevention and control measures should be carried out in the different regions.


Assuntos
Neoplasias , População Rural , Adolescente , China/epidemiologia , Feminino , Humanos , Incidência , Sistema de Registros , População Urbana , Útero
4.
Zhonghua Yi Xue Za Zhi ; 101(36): 2906-2908, 2021 Sep 28.
Artigo em Zh | MEDLINE | ID: mdl-34587732

RESUMO

A total of 106 patients who were diagnosed with Bosniak catergory ⅡF or Ⅲ cystic renal masses (CRM) and underwent surgery in Zhongshan-Xuhui Hospital and Xuhui District Central Hospital between January 2018 and December 2019 were retrospectively analyzed. The diagnostic accuracy of renal cyst index (RCI) and Bosniak classification system was compared by analyzing the relevant parameters including the sensitivity and specificity. There were 62 males and 44 females, with a median age of 56 years old. Among the 106 CRM, 72 were benign and 34 were malignant. The sensitivity and specificity of RCI was 94.12% and 81.94%, respectively, while the sensitivity and specificity of Bosniak classification system was 73.53% and 80.56%, respectively. Chi-square test revealed that the sensitivity of RCI was significantly higher than that of Bosniak classification system (P=0.023). The current study indicates that RCI is a simple and feasible method which can provide quantitative evaluation for predicting characteristics of CRM.


Assuntos
Doenças Renais Císticas , Neoplasias Renais , Feminino , Humanos , Rim , Doenças Renais Císticas/diagnóstico , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
5.
Insect Mol Biol ; 27(3): 319-332, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29441628

RESUMO

Body shape is one of the most prominent and basic characteristics of any organism. In insects, abundant variations in body shape can be observed both within and amongst species. However, the molecular mechanism underlying body shape fine-tuning is very complex and has been largely unknown until now. In the silkworm Bombyx mori, the tubby (tub) mutant has an abnormal short fat body shape and the abdomen of tub larvae expands to form a fusiform body shape. Morphological investigation revealed that the body length was shorter and the body width was wider than that of the Dazao strain. Thus, this mutant is a good model for studying the molecular mechanisms of body shape fine-tuning. Using positional cloning, we identified a gene encoding the serine protease homologue, B. mori scarface (Bmscarface), which is associated with the tub phenotype. Sequence analysis revealed a specific 312-bp deletion from an exon of Bmscarface in the tub strain. In addition, recombination was not observed between the tub and Bmscarface loci. Moreover, RNA interference of Bmscarface resulted in the tub-like phenotype. These results indicate that Bmscarface is responsible for the tub mutant phenotype. This is the first study to report that mutation of a serine protease homologue can induce an abnormal body shape in insects.


Assuntos
Bombyx/genética , Proteínas de Insetos/genética , Serina Proteases/genética , Animais , Tamanho Corporal , Bombyx/crescimento & desenvolvimento , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Filogenia , Análise de Sequência de Proteína , Serina Proteases/química , Serina Proteases/metabolismo
6.
Zhonghua Yi Xue Za Zhi ; 98(6): 427-431, 2018 Feb 06.
Artigo em Zh | MEDLINE | ID: mdl-29429253

RESUMO

Objective: To investigate the relationship between the content of human telomerase reverse transcriptase (hTERT) and its clinical features in serum free DNA in patients with different degree of spinal cord injury. Methods: From December 2013 to December 2016, inpatients of the Central Hospital of Bazhong, Sichuan Province were enrolledand divided into the experimental group, the disease control group and the negative control group. For the experimental group: 46 patients with spinal cord injury were graded according to the criteria of the American Association of Spinal Cord Injury (ASIA), including 12 cases of grade A, 10 cases of grade B, 10 cases of grade C, 7 cases of grade D and 7 cases of grade E; for the disease control group: 15 patients with spinal fractures (without spinal cord injury) at the same period were included; and for the negative control group: 20 healthy adult volunteers aged 18-50 years were selected.Real-time fluorescence quantitative PCR and immunoblotting were performed to detect the content of hTERT in serum free DNA both in patients and healthy controls and to compare the difference between them. The results of the somatosensory evoked potential (SEP) of all patients were compared and analyzed.The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of hTERT content in serum free DNA in patients with spinal cord injury. Results: Comparison of serum free DNA hTERT content: in the experimental group, the serum free DNA hTERT content of grade A, B, C, D, E was (99.63±8.23), (76.24±4.37), (46.07±5.43), (16.30±0.95) and (15.74±1.12)µg/L, respectively.While it was (15.01±1.39)µg/L in the disease control group and (14.54±1.03)µg/L in the negative control group. The total difference was statistically significant between patients of each group and the control group (F=857.917, P<0.001). Comparison of the protein content of TERT: in the experimental group, the protein content of TERT of grade A, B, C, D, E was 0.736±0.214, 0.641±0.172, 0.606±0.184, 0.411±0.132 and 0.307±0.152, respectively.The protein content of TERT in the disease control group and the negative control group was about 0.312±0.098 and 0.322±0.177, the difference between patients of each group and the control group was statistically significant (F=62.461, P<0.001). Detection results of surface evoked potential (SEP) showed that in the experimental group, level A patients all had conduction block.Two cases of level B patients had conduction block and 8 cases had delayed conduction.Among level C patients, 1 case had conduction block, 9 cases had delayed conduction.Among level D patients and patients from the control group and the negative control group, SEP detection all had no conduction block. Conclusion: The detection of the hTERT content in serum free DNA in patients with spinal cord injury has a certain guiding significance for the diagnosis of spinal cord injury and the degree of injury.


Assuntos
Traumatismos da Medula Espinal , Adolescente , Adulto , DNA , Proteínas de Ligação a DNA , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase , Adulto Jovem
7.
Scand J Immunol ; 85(4): 264-271, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28128471

RESUMO

The Fcγ receptor IIIA (FcγRIIIA) has traditionally been known as a positive regulator of immune responses. Consistent with this, mice deficient in FcγRIIIA are protected from various inflammation-associated pathologies including several autoimmune diseases. In contrast to this accepted dogma, we show here that mice lacking FcγRIIIA developed increased rather than reduced both humoral and cellular immune responses to mucosal (sublingual) immunization with ovalbumin (OVA) given together with the strong mucosal adjuvant cholera toxin as well as to parenteral (subcutaneous) immunization with OVA in complete Freund's adjuvant. After either route of immunization, in comparison with concomitantly immunized wild-type mice, FcγRIIIA-/- mice had increased serum anti-OVA IgG (IgG1 but not IgG2) antibody responses as well as augmented cellular responses that included memory B cells and effector T cells. The increments in immune responses in FcγRIIIA-/- mice were similar to those seen in FcγRIIB-/- mice. Furthermore, OVA-pulsed FcγRIIIA-/- DCs, similar to OVA-specific FcγRIIB-/- DCs, had enhanced capacity to activate OVA-specific OT-II T cells, which was even further pronounced when DCs were pulsed with IgG1-complexed OVA. Our data support an inhibitory-regulatory role of FcγRIIIA on vaccine/adjuvant-induced immune responses and demonstrate that lack of FcγRIIIA can promote rather than suppress both humoral and cellular immune responses.


Assuntos
Linfócitos B/imunologia , Imunidade Celular/genética , Imunidade Humoral/genética , Imunoglobulina G/imunologia , Receptores de IgG/genética , Linfócitos T/imunologia , Adjuvantes Imunológicos , Animais , Toxina da Cólera/imunologia , Adjuvante de Freund/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunização/métodos , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mucosa/imunologia , Ovalbumina/imunologia
8.
Heredity (Edinb) ; 118(6): 578-584, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28121309

RESUMO

In insects, there is a considerable diversity in leg distribution on the body, including number, segmental arrangement, morphological identity and consequent function, but the genetic basis for these differences is not well understood. Here by positional cloning, we showed that a ~355 kb region, including Bombyx mori Ultrabithorax (BmUbx) and abdominal-A (Bmabd-A), was responsible for the silkworm mutant Kh-extra-crescents-like (EKh-l) that displayed additional thoracic limb-like legs on the first abdominal segment (A1) and occasionally on the second abdominal segment (A2). We found that BmUbx gene was downregulated at both messenger RNA level and protein level in EKh-l embryo, while its expression domain in the EKh-l embryo was almost the same as that in the wild type. Whereas Bmabd-A was upregulated at both levels and was ectopically overexpressed on the supernumerary leg-bearing segments in EKh-l. Compared with the previously reported Ecs-l mutant in which increased expression of both BmUbx and Bmabd-A gave rise to ectopic proleg-like appendages on the same segments, we propose that overexpressed Bmabd-A gene is capable to promote the outgrowth of extra leg appendages on A1 and A2 segments, whereas BmUbx gene is required to specify accurate morphologies of the ectopic legs in a dosage-dependent manner in silkworm. These results provide insights into how these hox genes regulate the leg morphologic diversity on the same segments.


Assuntos
Bombyx/embriologia , Extremidades , Dosagem de Genes , Genes Homeobox , Proteínas de Insetos/genética , Animais , Bombyx/genética , Mapeamento Cromossômico , Regulação da Expressão Gênica no Desenvolvimento , Ligação Genética
9.
Phytopathology ; 107(1): 92-99, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27571309

RESUMO

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is a destructive disease in wheat. A population consisting of 229 F2 and F2:3 plants derived from the cross PI 672538 × L661 was used to evaluate the reactions to FHB. The FHB resistance data distribution in the F2 population indicates that some quantitative trait loci (QTLs) were controlling the FHB resistance in PI 672538. We further detected two major QTLs (Qfhs-2B, Qfhs-3B) from analysis of the resistance data and the PCR-amplified results using WinQTLCart 2.5 software. Qfhs-2B, flanked by Xbarc55-2B and Xbarc1155-2B, explained more than 11.6% of the phenotypic variation of the percentage of diseased spikelets (PDS), and Qfhs-3B, flanked by Xwmc54-3B and Xgwm566-3B, explained more than 10% of the PDS phenotypic variation in the F2:3 population. In addition, Qfhs-3B was different from Fhb1 in terms of the pedigree, inheritance, resistance response, chromosomal location, and marker diagnosis. We also detected QTLs for other disease resistance indices, including the percentage of damaged kernels and 1,000-grain weight, in similar chromosomal regions. Therefore, the FHB resistance of PI 672538 was mainly controlled by two major QTLs, mapped on 2B (FhbL693a) and 3B (FhbL693b). PI 672538 could be a useful germplasm for improving wheat FHB resistance.


Assuntos
Resistência à Doença/genética , Fusarium/fisiologia , Doenças das Plantas/imunologia , Locos de Características Quantitativas/genética , Triticum/genética , Mapeamento Cromossômico , Doenças das Plantas/microbiologia , Sementes/genética , Sementes/imunologia , Sementes/microbiologia , Triticum/imunologia , Triticum/microbiologia
10.
J Integr Neurosci ; 16(1): 33-55, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28891498

RESUMO

In this study, we provide a foundational model of ion transport processes in the intracellular and extracellular compartments of neurons at the nanoscale. There are two different kinds of ionic transport processes: (i) ionic transport across the neuronal membrane (trans-membrane), and (ii) ionic transport along both the intracellular and extracellular surfaces of the membrane. Brownian dynamics simulations are used to give a description of ionic trans-membrane transport. Electro-diffusion is used to model ion transport along the membrane surface, and the two transport processes can be linked analytically. In our model, we found that the interactions between ions and ion channels result in high-frequency ionic oscillations during trans-membrane transport. In ion transport along the membrane, high-frequency ionic oscillations may be evoked on both the intracellular and extracellular surfaces of the plasma membrane. The electric field caused by Coulomb interactions between the ions is found to be the most likely origin of those ionic oscillations.


Assuntos
Transporte de Íons/fisiologia , Potenciais da Membrana/fisiologia , Modelos Neurológicos , Neurônios/metabolismo , Animais , Difusão , Eletricidade , Canais Iônicos/metabolismo , Íons/metabolismo
11.
Int J Dent Hyg ; 15(1): 16-22, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27095145

RESUMO

BACKGROUND: Self-ligating brackets (SLBs) are widely adopted in clinic owing to their claimed superiorities. Here, we collected and analysed all randomized controlled clinical trials (RCTs) comparing SLBs with conventional brackets (CBs) and thereby investigated whether SLBs can relieve discomfort or promote oral hygiene. METHODS: Electronic databases including MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, Chinese BioMedical Literature Database and the China National Knowledge Infrastructure were searched to find out RCTs comparing active or passive SLBs with CBs. Two reviewers extracted the data and assessed risks of bias independently. Any disagreement between them was resolved through discussion with a third reviewer. Meta-analysis was conducted on Review Manager 5.3. RESULTS: A total of 12 RCTs with 575 participants were included, and eight of the trials were synthesized quantitatively. Two trials were assessed as low risk of bias, whereas others as unclear risk of bias. Passive SLBs and CBs are not significantly different in plaque control. SLBs and CBs are not significantly different in discomfort reduction at any of four time points (4 h, 24 h, 3 days and 7 days). CONCLUSIONS: Clinical evidences from existing RCTs suggest that SLBs do not outperform CBs in reliving discomfort or promoting oral health in clinic.


Assuntos
Higiene Bucal , Braquetes Ortodônticos , Humanos , Braquetes Ortodônticos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Insect Mol Biol ; 25(2): 93-104, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26661290

RESUMO

Speckled (Spc), an X-ray-induced lethal mutant of Bombyx mori, exhibits a mosaic dark-brown-spotted larval epidermis in both sexes and egg-laying problems only in females. Here, we report the morphological characterization and molecular mapping of the Spc mutant. Morphological investigations revealed that the epidermal ultrastructure of the small, dark-brown spots was more dense than that of the white regions in both Spc/+ mutants and wild type, and that the lethality of the Spc/Spc mutants occurred during early embryogenesis. Furthermore, the ovarioles and ovipositor were disconnected in approximately 85.5% of Spc/+ females, a further 2.5% had a connection between the ovarioles and ovipositor that was too narrow to lay eggs. The remaining females showed a normal connection similar to that of the wild type. We successfully narrowed down the location of the Spc mutation to a region on chromosome 4 that was ∼1041 kb long. Gene-prediction analysis identified 25 candidate genes in this region. Chromosome structure analysis indicated that a ∼305 kb deletion was included in the mapping region. Temporal and spatial reverse transcription PCR (RT-PCR) analysis showed that several genes in the mapped region are associated with the Spc mutant. Although the genes responsible for the Spc mutation were not definitively identified, our results further the current understanding of the complex mechanism underlying the multiple morphological defects in Spc mutants.


Assuntos
Bombyx/genética , Desenvolvimento Embrionário/genética , Larva/genética , Pigmentação/genética , Animais , Bombyx/crescimento & desenvolvimento , Bombyx/efeitos da radiação , Mapeamento Cromossômico , Desenvolvimento Embrionário/efeitos da radiação , Epiderme/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/efeitos da radiação , Masculino , Mutação/efeitos da radiação , Raios X
13.
Phys Rev Lett ; 116(7): 077002, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943553

RESUMO

We report the evolution of superconductivity in an FeSe thin flake with systematically regulated carrier concentrations by the liquid-gating technique. With electron doping tuned by the gate voltage, high-temperature superconductivity with an onset at 48 K can be achieved in an FeSe thin flake with T_{c} less than 10 K. This is the first time such high temperature superconductivity in FeSe is achieved without either an epitaxial interface or external pressure, and it definitely proves that the simple electron-doping process is able to induce high-temperature superconductivity with T_{c}^{onset} as high as 48 K in bulk FeSe. Intriguingly, our data also indicate that the superconductivity is suddenly changed from a low-T_{c} phase to a high-T_{c} phase with a Lifshitz transition at a certain carrier concentration. These results help to build a unified picture to understand the high-temperature superconductivity among all FeSe-derived superconductors and shed light on the further pursuit of a higher T_{c} in these materials.

14.
Phys Rev Lett ; 116(14): 147001, 2016 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-27104721

RESUMO

Here, we experimentally study the origin of d-electron heavy fermion (HF) behavior in iron-based superconductors (FeSCs) AFe_{2}As_{2} (A=K, Rb, Cs). Nuclear magnetic resonance on ^{75}As reveals a universal coherent-incoherent crossover with a characteristic temperature T^{*}. Below T^{*}, a so-called "Knight shift anomaly" is first observed in FeSCs, which exhibits a scaling behavior similar to f-electron HF materials. Furthermore, the scaling rule also regulates the manifestation of magnetic fluctuation. These results undoubtedly support an emergent Kondo lattice scenario for the d-electron HF behavior, which qualifies the AFe_{2}As_{2} (A=K, Rb, Cs) as d-electron HF superconductors.

15.
Phys Rev Lett ; 115(22): 226401, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26650311

RESUMO

We measure the magnetotransport properties of the three-dimensional Dirac semimetal Cd_{3}As_{2} single crystal under magnetic fields up to 36 T. Shubnikov-de Haas (SdH) oscillations are clearly resolved and the n=1 Landau level is reached. A detailed analysis on the intercept of the Landau index plot reveals a significant dependence of the SdH phase factor on the orientation of the applied magnetic field. When the magnetic field is applied in the [001] direction, i.e., along the fourfold screw axis of the tetragonal crystal structure, a nontrivial π Berry phase, as predicted for the Dirac fermions, is observed. However, in a magnetic field tilted away from the [001] direction, the π Berry phase is evidently reduced, and a considerable enhancement of the effective mass is also revealed. Our observations demonstrate that the Dirac dispersion in Cd_{3}As_{2} is effectively modified in a tilted magnetic field, whereas the preserved π Berry phase in a magnetic field along the [001] direction can be related to the realization of the Weyl fermions. The sudden change of the SdH phase also indicates a possible topological phase transition induced by the symmetry-breaking effect.

16.
Phys Rev Lett ; 115(18): 186403, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26565480

RESUMO

In a semimetal, both electrons and holes contribute to the density of states at the Fermi level. The small band overlaps and multiband effects engender novel electronic properties. We show that a moderate hydrostatic pressure effectively suppresses the band gap in the elemental semiconductor black phosphorus. An electronic topological transition takes place at approximately 1.2 GPa, above which black phosphorus evolves into a semimetal state that is characterized by a colossal positive magnetoresistance and a nonlinear field dependence of Hall resistivity. The Shubnikov-de Haas oscillations detected in magnetic field reveal the complex Fermi surface topology of the semimetallic phase. In particular, we find a nontrivial Berry phase in one Fermi surface that emerges in the semimetal state, as evidence of a Dirac-like dispersion. The observed semimetallic behavior greatly enriches the material property of black phosphorus and sets the stage for the exploration of novel electronic states in this material.

17.
Clin Radiol ; 70(4): 351-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25466436

RESUMO

AIM: To determine the accuracy of MRI versus ultrasound for Morton's neuroma. MATERIALS AND METHODS: A search was undertaken for clinical studies published in any language in PubMed up to the date of December 2013. Studies assessing the accuracy of the ultrasound or MRI for the diagnosis of Morton's neuroma were included. Data were pooled for meta-analysis. Study selection, data collection, and extraction were performed independently by two authors. Meta-disc 1.4 and Revman 5.2 software were applied for statistical analysis. RESULTS: The study included 12 studies; 217 patients underwent MRI and 241 underwent ultrasound examinations. There appeared greater diagnostic accuracy for ultrasound than MRI for the diagnosis of Morton's neuroma (ultrasound sensitivity 90%, specificity 88%, positive likelihood ratio 2.77, negative likelihood ratio 0.16 versus MRI sensitivity 93%, specificity 68%, positive likelihood ratio 1.89, negative likelihood ratio 0.19). CONCLUSIONS: The available evidence suggests that ultrasound can provide better accuracy for the diagnosis of Morton's neuroma than MRI.


Assuntos
Doenças do Pé/diagnóstico , Neuroma/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Doenças do Pé/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroma/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia , Adulto Jovem
18.
Genet Mol Res ; 14(3): 11013-22, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26400331

RESUMO

Oxaliplatin (L-OHP) is one of the most commonly used anticancer drugs in adjuvant treatment of colon cancer after complete resection of the primary tumor and treatment of metastatic colorectal cancer. Cancer cells eventually become resistant to L-OHP, which diminishes its curative effect. However, the mechanism of action of L-OHP remains unknown. In this study, an L-OHP-resistant human colon cancer cell line, HT29/L-OHP, was established by gradually increasing the dose of L-OHP in culture. The expression levels of the tumor susceptibility gene 101 (tsg101) and the TSG101 protein in HT29 and HT29/L-OHP cell lines were examined by reverse transcription-polymerase chain reaction and western blot analysis. In addition, the expression levels of several apoptosis-regulating protein markers were determined using immunohistochemistry-staining assays. We found that the expression of tsg101 mRNA and of TSG101 protein were significantly higher in the HT29/L-OHP cell line than in its parent, HT29 (P < 0.05). In addition, the expression of multiple apoptosis-regulating protein markers were significantly increased (P < 0.05) in the HT29/L-OHP cell line. These data suggest that these markers could be useful as predictive markers for evaluating and comparing the efficacy and molecular pharmacology of chemotherapeutics.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Compostos Organoplatínicos/farmacologia , Fatores de Transcrição/metabolismo , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Proteínas de Ligação a DNA/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Células HT29 , Humanos , Concentração Inibidora 50 , Oxaliplatina , Fatores de Transcrição/genética , Transcriptoma
19.
J Oral Rehabil ; 42(8): 588-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25944587

RESUMO

Treatment outcomes of Angle Class II subdivision malocclusions may be compromised because of the uncertainty of the aetiology. Previous studies have reported controversial ideas about the origins, but the existence of a primary contributor still remains unknown. Functional factors have been mentioned as a probable cause, but until now, there have been no supporting data. This study was a cross-sectional investigation of the characteristics of Angle Class II subdivision malocclusion, including dental, skeletal and functional factors, by comparison of the subdivision group and the normal occlusion group. The evaluations of dental and skeletal asymmetries of both groups were carried out by cone-beam computed tomography (CBCT) and analysis of dental casts. The functional deviations were evaluated by cast mounting and measuring. In the subdivision group, the asymmetric position of the glenoid fossa was found to be the most significant skeletal asymmetry. No dentoalveolar asymmetry was found in this group. The most important finding was that, in subdivision malocclusions, functional deviation resulting in pseudoasymmetry occurred in 32.86% of the study participants. This deviation is probably related to the disharmonious arch width between maxillary and mandibular dental arches in the premolar section. The origin of Angle Class II subdivision malocclusion is multifactorial, with dental, skeletal and functional factors included. Functional deviation occurs, probably due to dental arch width disharmony. Asymmetric position of the glenoid fossa may account for most of the skeletal asymmetry.


Assuntos
Ossos Faciais/diagnóstico por imagem , Má Oclusão Classe II de Angle/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Transversais , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Má Oclusão Classe II de Angle/fisiopatologia , Adulto Jovem
20.
Theor Appl Genet ; 127(4): 843-53, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24487977

RESUMO

KEY MESSAGE: Stripe rust resistance transferred from Thinopyrum intermedium into common wheat was controlled by a single dominant gene, which mapped to chromosome 1B near Yr26 and was designated YrL693. Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a highly destructive disease of wheat (Triticum aestivum). Stripe rust resistance was transferred from Thinopyrum intermedium to common wheat, and the resulting introgression line (L693) exhibited all-stage resistance to the widely virulent and predominant Chinese pathotypes CYR32 and CYR33 and to the new virulent pathotype V26. There was no cytological evidence that L693 had alien chromosomal segments from Th. intermedium. Genetic analysis of stripe rust resistance was performed by crossing L693 with the susceptible line L661. F(1), F(2), and F(2:3) populations from reciprocal crosses showed that resistance was controlled by a single dominant gene. A total 479 F(2:3) lines and 781 pairs of genomic simple sequence repeat (SSR) primers were employed to determine the chromosomal location of the resistance gene. The gene was linked to six publicly available and three recently developed wheat genomic SSR markers. The linked markers were localized to wheat chromosome 1B using Chinese Spring nulli-tetrasomic lines, and the resistance gene was localized to chromosome 1B based on SSR and wheat genomic information. A high-density genetic map was also produced. The pedigree, molecular marker data, and resistance response indicated that the stripe rust resistance gene in L693 is a novel gene, which was temporarily designated YrL693. The SSR markers that co-segregate with this gene (Xbarc187-1B, Xbarc187-1B-1, Xgwm18-1B, and Xgwm11-1B) have potential application in marker-assisted breeding of wheat, and YrL693 will be useful for broadening the genetic basis of stripe rust resistance in wheat.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Poaceae/genética , Triticum/genética , Triticum/microbiologia , Basidiomycota/fisiologia , Cruzamentos Genéticos , Eletroforese em Gel de Poliacrilamida , Marcadores Genéticos , Padrões de Herança/genética , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Coloração pela Prata
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