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1.
Zhonghua Bing Li Xue Za Zhi ; 53(3): 276-281, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38433056

RESUMO

Objective: To investigate the clinicopathological features and molecular genetic characteristics of esophageal carcinoma with ductal differentiation, and to summarize the experiences in its diagnosis and treatment. Methods: A total of 17 cases of esophageal carcinoma with ductal differentiation diagnosed in Ningbo Clinical Pathological Diagnosis Center, Ningbo, China from June 2011 to December 2022 were collected. The clinical information and pathological diagnosis was reviewed. The tumor histological features and immunohistochemical results were analyzed. The next-generation sequencing was performed to detect and analyze the gene mutations in tumor samples. Results: The 17 patients included in this study were 54-77 years old, with a median age of 66 years. There were 16 males and 1 female. Among them, 9 cases were mainly carcinoma with ductal differentiation. The squamous epithelium on the tumor's surface was accompanied by high-grade intraepithelial neoplasia. The tumor and atypical squamous epithelium were transitional, and the focus was accompanied by various proportions of squamous cell carcinoma component (less than 10%). The other 8 cases were mostly squamous cell carcinoma, basaloid squamous cell carcinoma or sarcomatoid carcinoma with various degrees of tumor specific differentiation and focal area of carcinoma with ductal differentiation (less than 10%). The tumor cells in the area with ductal differentiation were mainly arranged in small tubes, while the tubes showed a double-layer structure, including the inner cells and outer cells of the lumen. Immunohistochemical results showed that the outer cells of the tumorous tubules expressed p63, p40, CK5/6 and CK34ßE12, while the inner cells expressed CK7. Compared with esophageal squamous cell carcinoma reported in the literature, the frequency of gene mutations such as MYC (P=0.002), TP63 (P=0.002), CDKN1C (P=0.002) and NFE2L2 (P=0.045) was significantly lower in this group of cases. At the signaling pathway level, the mutation frequency of NOTCH signaling pathway (P=0.041) was significantly higher, while the mutation frequencies of NRF2 pathway (P=0.013) and PI3K pathway (P=0.009) were significantly lower than that of esophageal squamous cell carcinoma. Conclusion: Esophageal carcinoma with ductal differentiation is a type of esophageal carcinoma with unique morphology, and its molecular changes are also significantly different from those of conventional esophageal squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Neoplasias Esofágicas/genética , Fosfatidilinositol 3-Quinases , Diferenciação Celular , Carcinoma de Células Escamosas/genética
2.
Nat Commun ; 14(1): 7405, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974022

RESUMO

Kondo impurities provide a nontrivial probe to unravel the character of the excitations of a quantum spin liquid. In the S = 1/2 Kitaev model on the honeycomb lattice, Kondo impurities embedded in the spin-liquid host can be screened by itinerant Majorana fermions via gauge-flux binding. Here, we report experimental signatures of metallic-like Kondo screening at intermediate temperatures in the Kitaev honeycomb material α-RuCl3 with dilute Cr3+ (S = 3/2) impurities. The static magnetic susceptibility, the muon Knight shift, and the muon spin-relaxation rate all feature logarithmic divergences, a hallmark of a metallic Kondo effect. Concurrently, the linear coefficient of the magnetic specific heat is large in the same temperature regime, indicating the presence of a host Majorana metal. This observation opens new avenues for exploring uncharted Kondo physics in insulating quantum magnets.

3.
Zhonghua Gan Zang Bing Za Zhi ; 31(12): 1318-1325, 2023 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-38253077

RESUMO

Objective: To analyze the correlation between the histological classification of hepatocellular carcinoma (HCC), especially macrotrabecular-massive (MTM), tumor invasiveness, and prognosis. Methods: The clinical and follow-up data of 246 consecutive HCC cases who met the inclusion criteria from 2015 to 2018 were retrospectively analyzed. They were divided into trabecular/pseudoglandular, trabecular/patchy, and MTM types according to the histological classification. The relationship between each type and related clinicopathological features was analyzed. The Kaplan-Meier method was used to plot tumor-free survival (DFS) and overall survival (OS) curves. Log rank tests, COX univariate, and multivariate regression analyses were conducted to analyze the relationship between clinical features, including histological classification, DFS, and OS. Results: Trabecular/pseudoglandular, trabecular/nodular, and MTM type proportions were 44.7% (110 cases), 32.9% (81 cases), and 22.4% (55 cases), respectively. The results of the clinicopathological features showed that MTM-type HCC was significantly more invasive than the other two types, with alpha-fetoprotein (AFP) ≥400 ng/ml, tumor diameter≥8 cm, no tumor capsule, poor differentiation, and MVI positivity proportions, and the differences were statistically significant (P < 0.05).The proportion of MTM-type HCC patients with American Joint Committee on Cancer TNM Stage III to IV and Chinese Liver Cancer Staging (CNLC) II to II was significantly higher than that of the first two types, and the differences were statistically significant (P < 0.05). In addition, the proportion of MTM subtypes undergoing transcatheter arterial chemoembolization was also raised (P < 0.05). The DFS and OS were significantly lower for MTM-type HCC compared to trabecular/pseudoductal-type HCC at 1-, 3-, and 5-years, and the differences were statistically significant (P < 0.05). Univariate analysis indicated that strongly invasive clinical pathological features such as alpha fetoprotein (AFP) ≥400 ng/ml, tumor diameter ≥ 8 cm, no tumor capsule, poor differentiation, positive microvascular invasion, tumor stage, and MTM staging were all risk factors affecting DFS and OS (P < 0.05). Multivariate COX analysis showed that MTM histological staging, AFP ≥ 400 ng/ml, tumor non-encapsulation, satellite nodules, CNLC stages II~III, and TNM stages III~IV were independent risk factors for DFS (P < 0.05), while AFP ≥ 400 ng/ml, tumor non-encapsulation, and CNLC stage II~III were independent risk factors for OS ( P < 0.05). Conclusion: Histological classification is highly correlated with tumor invasiveness and HCC prognosis. Trabecular/pseudoglandular types have lower malignancy and a better prognosis, while MTM types exhibit strong invasive features and a poor prognosis.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , alfa-Fetoproteínas , Estudos Retrospectivos
4.
Zhonghua Zhong Liu Za Zhi ; 44(11): 1202-1207, 2022 Nov 23.
Artigo em Chinês | MEDLINE | ID: mdl-36380669

RESUMO

Objective: To study the impact of regional positive lymph node ratio (LNR) on prognosis of patients with gallbladder carcinoma. Methods: The clinicopathological and survival data of 53 patients with gallbladder carcinoma who underwent radical resection with regional lymph node metastasis in Ningbo University Affiliated Lihuili Hospital from May 2012 to December 2020 were collected, and receiver operating characteristic curve (ROC) was used to determine the optimal cut-off value of LNR for predicting postoperative survival status in patients with gallbladder carcinoma. According to the critical value, the patients were divided into low LNR group and high LNR group. The clinicopathological features and prognosis of the two groups were compared. Log rank test was used for univariate analysis of prognostic factors in patients with gallbladder carcinoma, and Cox proportional hazards model was used for multivariate analysis. Results: A total of 417 regional lymph nodes were dissected in 53 patients, of which 144 lymph nodes were positive, with a positive rate of 34.5%. The optimal cut-off value of LNR for predicting postoperative survival status of patients with gallbladder carcinoma was 0.33. According to this cut-off value, patients were divided into low LNR group (LNR≤0.33, 28 cases) and high LNR group (LNR>0.33, 25 cases). The recurrence rates were 64.3% (18/28) and 88.0 % (22/25) in low LNR group and high LNR group, respectively. The median recurrence-free survival (RFS) was 8 and 7 months, respectively (P=0.032). In the low LNR group, the 1-, 3-, and 5-year survival rates were 56.2%, 38.4%, and 32.0%, respectively, and the median overall survival (OS) was 16 months. In the high LNR group, the 1-, 3-, and 5-year survival rates were 37.9%, 5.4%, and 0, respectively, and the median OS was 9 months. The postoperative survival rate of patients in the low LNR group was better than that in the high LNR group (P=0.008). Univariate analysis showed that LNR was even associated with RFS and OS in patients with gallbladder carcinoma (P<0.05). Multivariate analysis showed that LNR>0.33 was an independent risk factor for postoperative RFS (HR=1.977, 95% CI: 1.045-3.740), but not for OS (HR=1.561, 95% CI: 0.685-3.553). Conclusion: On the basis of clearing a sufficient number of regional lymph nodes, patients with gallbladder carcinoma with regional LNR>0.33 are more likely to relapse after operation, but the predictive value of LNR>0.33 OS is insufficient.


Assuntos
Neoplasias da Vesícula Biliar , Razão entre Linfonodos , Humanos , Neoplasias da Vesícula Biliar/patologia , Excisão de Linfonodo , Metástase Linfática/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Linfonodos/patologia , Prognóstico
6.
Phys Rev Lett ; 125(9): 097005, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915617

RESUMO

We report muon spin rotation and magnetic susceptibility experiments on in-plane stress effects on the static spin-stripe order and superconductivity in the cuprate system La_{2-x}Ba_{x}CuO_{4} with x=0.115. An extremely low uniaxial stress of ∼0.1 GPa induces a substantial decrease in the magnetic volume fraction and a dramatic rise in the onset of 3D superconductivity, from ∼10 to 32 K; however, the onset of at-least-2D superconductivity is much less sensitive to stress. These results show not only that large-volume-fraction spin-stripe order is anticorrelated with 3D superconducting coherence but also that these states are energetically very finely balanced. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. These results strongly suggest a similar pairing mechanism for spin-stripe order and the spatially modulated 2D and uniform 3D superconducting orders, imposing an important constraint on theoretical models.

8.
J Dairy Sci ; 102(6): 4978-4988, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981477

RESUMO

Fruit juice addition can influence the physiochemical and sensory properties of fermented milk. Effects of adding strawberry juice (15% vol/vol) pre- or postfermentation on particle size, rheology properties, volatile flavor profile, and microstructure of fermented goat milk were investigated. Samples with juice added prefermentation showed larger reinforcement in particle size, apparent viscosity, and storage and loss moduli than samples with juice added postfermentation. Compared with the control, all samples showed improved fruit aroma and reduced goaty flavor; this effect was more remarkable in samples in which juice was added before fermentation. Fermented goat milk with strawberry juice added prefermentation showed the highest levels of 1-hexanol and 2-hexen-1-ol (26.16 and 22.03%, respectively) and the lowest percentage of octanoic acid (2.47%), which are mainly responsible for fruit and goaty flavor, respectively. Microstructure analysis showed that samples with juice added prefermentation had a compact protein network. Results indicated that addition of strawberry juice before fermentation may be a good technology for developing a stirred strawberry fermented goat milk.


Assuntos
Aditivos Alimentares , Fragaria , Sucos de Frutas e Vegetais , Leite/química , Animais , Fermentação , Cabras , Paladar
9.
J Dairy Sci ; 101(11): 9680-9692, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30197146

RESUMO

Soybean lecithin is often used as a surfactant in food formulation. The aim of this study was to investigate the interactions between soybean lecithin (SL, 0-3%, wt/vol) and whey protein (WP, 10%, wt/vol) or polymerized whey protein (PWP, 10%, wt/vol) induced by heating WP solutions at 85°C for 0 to 20 min at pH 7.0. The samples were evaluated for zeta potential, particle size, morphology, rheological properties, thermal properties, secondary structure, and surface hydrophobicity. Zeta potential of WP increased linearly as SL level increased from 0 to 3%, whereas that of PWP changed with plateau at SL level of 1%, which may be due to the aggregation of SL. The addition of SL increased the particle size and apparent viscosity of both WP and PWP. All the samples exhibited different morphology depending on SL level and heating time according to transmission electron microscopy images. Whey protein showed obviously decreased gelation time and increased storage modulus in the presence of SL. Differential scanning calorimetry curves confirmed the effects of SL on the thermal properties of both WP and PWP. Circular dichroism spectra indicated that SL had effects on the secondary structure of both WP and PWP. The changes in surface hydrophobicity indicated the hydrophobic interactions between WP/PWP and SL. Data indicate that the physicochemical and functional properties of WP and PWP can be altered by adding soybean lecithin.


Assuntos
/química , Lecitinas/química , Proteínas do Soro do Leite/química , Animais , Fenômenos Químicos , Géis , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Polimerização , Reologia , Tensoativos , Termodinâmica , Viscosidade
10.
J Dairy Sci ; 101(6): 4879-4890, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29573795

RESUMO

Gamma radiation has been used in food processing for many years, though it has certain effects on food components. Whey protein solutions (10%/30%, wt/vol) were treated with gamma radiation at various dosages (10-25 kGy) and evaluated for microbial changes in the solutions and physicochemical and structural changes of whey proteins. Whey protein solutions after gamma radiation showed substantially lower populations of all viable microorganisms than those of controls. The 10% whey protein solution treated at radiation of 20 or 25 kGy remained sterile for up to 4 wk at room temperature. Gamma radiation increased viscosity and turbidity and decreased soluble nitrogen of whey protein solutions compared to nonradiated control samples regardless of radiation dosage. Nonreducing sodium dodecyl sulfate-PAGE suggested that whey proteins under gamma radiation treatment formed aggregates with high molecular weights. Reducing sodium dodecyl sulfate-PAGE showed that disulfide bonds played a role in gamma radiation-induced whey protein cross-linking. Scanning and transmission electron microscopy micrographs exhibited large aggregates of whey proteins after gamma radiation treatment. Results suggested that gamma radiation could be applied to whey protein solution for purposes of reducing microbial counts and cross-linking protein molecules.


Assuntos
Bactérias/efeitos da radiação , Proteínas do Soro do Leite/efeitos da radiação , Soro do Leite/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bovinos , Eletroforese em Gel de Poliacrilamida , Irradiação de Alimentos , Raios gama , Microscopia Eletrônica de Transmissão , Modelos Biológicos , Viscosidade , Soro do Leite/efeitos da radiação , Proteínas do Soro do Leite/química
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(5): 289-293, 2017 May 09.
Artigo em Chinês | MEDLINE | ID: mdl-28482444

RESUMO

Objective: To illuminate the effect of NALP3 inflammasome on regulating the expression of cytokines of macrophages in periodontitis. Methods: RAW264.7 cells were cultured and divided into three groups. The first group stayed normal as control, the second group was stimulated by 1 mg/L Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS), the third group was pretreated with AC-YVAD-CMK (caspase-1 inhibitor) before stimulated with 1 mg/L Pg LPS. RAW264.7 cells pretreated with various concentrations (0, 5, 10, 25, 50, 75, 100, 200 µmol/L) of AC-YVAD-CMK for 2 h, and stimulated by 1 mg/L Pg LPS for 24 h in the third group. After that, cell survival rate were detected by cell counting kit-8. Every group cells gene transcription of NALP3 and interleukin-1ß (IL-1ß) were detected by quantitative real-time PCR (qPCR) after 6 h, protein expression of NALP3 and IL-1ß were separately detected by Western blotting and enzyme linked immunosorbent assay (ELISA) after 24 h, respectively. Results: It is observed that treatment with 5, 10, 25, 50, 75, 100, 200 µmol/L AC-YVAD-CMK did not significantly affect the viability of RAW264.7 cells. qPCR showed that mRNA expression of IL-1ß level (1.03±0.08, 5.48±0.22, 4.31±0.20) and NALP3 level (0.96±0.05, 2.62±0.44, 1.73±0.09). Western blotting showed that protein expression of NALP3 level (1.00±0.10, 2.34±0.04, 1.64±0.04), ELISA showed protein secretion of IL-1ß level ([40.20±0.25], [61.50±1.81], [52.40±1.91] ng/L). After stimulated by Pg LPS, mRNA and protein expression of IL-1ß (P<0.01, P<0.01) and NALP3 (P<0.01, P<0.01) significantly increased; but the expression of IL-1ß (P=0.002, P=0.027) and NALP3 (P<0.01, P<0.01) were decreased when pretreated with AC-YVAD-CMK. Conclusions: NALP3 inflammasome signal pathway can be activated by Pg LPS in RAW264.7. Block of the pathway can inhibit Pg LPS-induced secretion of cytokines.


Assuntos
Clorometilcetonas de Aminoácidos/farmacologia , Citocinas/metabolismo , Inflamassomos/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Periodontite/metabolismo , Porphyromonas gingivalis/química , Clorometilcetonas de Aminoácidos/administração & dosagem , Sobrevivência Celular , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Periodontite/patologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Serpinas/farmacologia , Transdução de Sinais , Fatores de Tempo , Proteínas Virais/farmacologia
12.
Osteoarthritis Cartilage ; 25(6): 832-838, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28043937

RESUMO

OBJECTIVE: We assessed the efficacy and safety of duloxetine (60 mg, once daily), compared with placebo, during a 13-week treatment period in Chinese patients with chronic pain due to osteoarthritis (OA). DESIGN: Patients were at least 40 years old (male or female) who met American College of Rheumatology clinical and radiographic criteria for the diagnosis of OA of the knee or hip. The primary efficacy measure in this phase 3, randomized, double-blind, placebo-controlled clinical trial was assessment of pain severity by the Brief Pain Inventory (BPI) 24-h Average Pain rating. The clinical trial was conducted at 17 study centers. Statistical approaches included mixed-effects model repeated measures and analysis of covariance. A Fisher exact test was applied to categorical variables. RESULTS: Of 407 patients randomized (duloxetine: N = 205; placebo: N = 202), 166 (81.0%) patients from the duloxetine group and 176 (87.1%) patients from the placebo group completed the 13-week treatment phase. The majority (76.4%) of patients was female; mean age was 60.5 years. Duloxetine-treated patients reported significant pain reduction, compared with placebo treatment, on the BPI 24-h Average Pain rating (least-squares mean (LS Mean) change from baseline to endpoint [95% confidence interval (CI)], duloxetine: -2.23; placebo: -1.73; difference = -0.50 [-0.80, -0.20]; P = 0.001). The incidence of discontinuations due to adverse events was 9.0% in duloxetine-treated patients and 4.5% in placebo-treated patients (P = 0.109). CONCLUSIONS: This study demonstrated the efficacy of duloxetine in Chinese patients with chronic pain due to OA. The safety profile of duloxetine observed in this study was consistent with that in previous duloxetine trials. This trial is registered with ClinicalTrials.gov (NCT01931475).


Assuntos
Analgésicos/uso terapêutico , Dor Crônica/tratamento farmacológico , Cloridrato de Duloxetina/uso terapêutico , Osteoartrite do Quadril/tratamento farmacológico , Osteoartrite do Joelho/tratamento farmacológico , Idoso , Povo Asiático , Dor Crônica/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/complicações , Osteoartrite do Joelho/complicações , Resultado do Tratamento
13.
Dalton Trans ; 45(18): 7555-8, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27080152

RESUMO

We report field-dependent magnetization measurements on monolayers of [Dy(Pc)2] on quartz, prepared by the Langmuir-Blodgett technique. The films are thoroughly characterized by means of X-ray reflectivity and atomic force microscopy. The magnetisation of the sample is measured through the magnetic circular dichroism of a ligand-based electronic transition.

14.
Int J Clin Pract ; 69(9): 957-66, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25939897

RESUMO

BACKGROUND: Duloxetine has been approved in the United States, European Union and some Asian countries for the treatment of diabetic peripheral neuropathic pain (DPNP). We assessed the efficacy and safety of duloxetine (60 mg once daily) compared with placebo in Chinese patients suffering from DPNP. METHODS: This was a phase 3, multicenter, randomised, double-blind, parallel, placebo-controlled, 12-week trial of the treatment of DPNP with duloxetine. Subjects were male and female outpatients ≥ 18 years of age with DPNP, as assessed by the Michigan Neuropathy Screening Instrument, and had a rating of ≥ 4 on the Brief Pain Inventory-Modified Short Form-Severity weekly average pain item. The primary efficacy measure was the reduction in pain severity from baseline to 12 weeks, as measured by the weekly mean of 24-h average pain ratings recorded in the patient's diary. Mean changes from baseline in efficacy measures were analysed by a restricted maximum likelihood-based, mixed-effects model repeated measures approach and by analysis of covariance. RESULTS: Of the 405 patients randomised, 203 patients were assigned to duloxetine 60 mg once daily and 202 patients were assigned to placebo. Duloxetine-treated patients showed significantly greater pain relief on 24-h average pain ratings compared with placebo-treated patients each week of the 12-week study period [week 12: least squares (LS) mean change duloxetine: -2.40, placebo: -1.97; LS mean change difference (95% confidence interval) = -0.43 (-0.82, -0.04), p = 0.030]. Compared with placebo, patients treated with duloxetine experienced higher rates of nausea (p = 0.010), somnolence (p < 0.001) and asthenia (p = 0.002). CONCLUSIONS: Duloxetine-treated patients showed significantly greater pain relief compared with placebo-treated patients over the 12-week study period. Duloxetine was shown in Chinese patients to have a safety profile similar to that found in previous duloxetine trials.


Assuntos
Analgésicos/uso terapêutico , Neuropatias Diabéticas/tratamento farmacológico , Cloridrato de Duloxetina/uso terapêutico , Neuralgia/tratamento farmacológico , Inibidores da Recaptação de Serotonina e Norepinefrina/uso terapêutico , Adulto , Idoso , China , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estados Unidos
15.
Heredity (Edinb) ; 111(2): 147-56, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23591517

RESUMO

Elucidation of the evolutionary processes that constrain or facilitate adaptive divergence is a central goal in evolutionary biology, especially in non-model organisms. We tested whether changes in dynamics of gene flow (historical vs contemporary) caused population isolation and examined local adaptation in response to environmental selective forces in fragmented Rhododendron oldhamii populations. Variation in 26 expressed sequence tag-simple sequence repeat loci from 18 populations in Taiwan was investigated by examining patterns of genetic diversity, inbreeding, geographic structure, recent bottlenecks, and historical and contemporary gene flow. Selection associated with environmental variables was also examined. Bayesian clustering analysis revealed four regional population groups of north, central, south and southeast with significant genetic differentiation. Historical bottlenecks beginning 9168-13,092 years ago and ending 1584-3504 years ago were revealed by estimates using approximate Bayesian computation for all four regional samples analyzed. Recent migration within and across geographic regions was limited. However, major dispersal sources were found within geographic regions. Altitudinal clines of allelic frequencies of environmentally associated positively selected outliers were found, indicating adaptive divergence. Our results point to a transition from historical population connectivity toward contemporary population isolation and divergence on a regional scale. Spatial and temporal dispersal differences may have resulted in regional population divergence and local adaptation associated with environmental variables, which may have played roles as selective forces at a regional scale.


Assuntos
Adaptação Biológica/genética , Fluxo Gênico , Dispersão Vegetal/genética , Isolamento Reprodutivo , Rhododendron/classificação , Rhododendron/genética , Teorema de Bayes , Evolução Biológica , Meio Ambiente , Etiquetas de Sequências Expressas , Deriva Genética , Variação Genética , Repetições de Microssatélites , Família Multigênica , Filogeografia , Análise de Sequência de DNA , Taiwan
16.
Phys Rev Lett ; 110(13): 136805, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581357

RESUMO

With ellipsometry, x-ray diffraction, and resistance measurements we investigated the electric-field effect on the confined electrons at the LaAlO3/SrTiO3 interface. We obtained evidence that the localization of the electrons at negative gate voltage is induced, or at least enhanced, by a polar phase transition in SrTiO3 which strongly reduces the lattice polarizability and the subsequent screening. In particular, we show that the charge localization and the polar order of SrTiO3 both develop below ∼50 K and exhibit similar, unipolar hysteresis loops as a function of the gate voltage.

17.
Cells Tissues Organs ; 196(3): 271-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22414746

RESUMO

BACKGROUND: Mutations in 6 genes have been identified as being part of the etiology of amelogenesis imperfecta (AI) with various phenotypes in an isolated condition. Among them the FAM83H gene is the major contributor to the etiology of AI with unknown function. OBJECTIVE: This study aims to determine the phenotypic and molecular characterization of Chinese AI patients and to analyze the structure and function of the FAM83H protein. METHODS: We enrolled 6 hypocalcified AI and 3 hypoplastic AI families from the Chinese population. Mutation analysis was performed by amplifying and sequencing all exons including intron-exon borders for FAM83H and ENAM genes. Structural modeling and function analysis on the FAM83H protein were carried out by bioinformatic processing. RESULTS: No obvious anterior open bite was observed in all the investigated individuals. Five mutations (c.906T>G, c.924dupT, c.973C>T, c.1354C>T and c.2029C>T) in the C-terminal of the FAM83H gene were revealed, respectively, in 5 out of 6 hypocalcified AI families, and a splicing mutation c.534 + 1G>A in the ENAM gene was identified in 1 out of 3 hypoplastic AI families. Structural models of the N- and C-terminal regions of FAM83H were generated by homology modeling. The predicted structure of the FAM83H N-terminal shows resemblance to that of glycosyltransferases with GT-A folds, and the predicted structure of the FAM83H C-terminal possesses similarity to type I collagen protein. CONCLUSIONS: To our knowledge, this is the first report of AI with specific molecular variations in families of Chinese descent. Our study provides new insights into the structure and function of the FAM83H protein.


Assuntos
Amelogênese Imperfeita/genética , Povo Asiático , Mutação , Proteínas/genética , Amelogênese Imperfeita/etnologia , Amelogênese Imperfeita/patologia , Sequência de Aminoácidos , China/epidemiologia , Análise Mutacional de DNA , Bases de Dados de Proteínas , Proteínas da Matriz Extracelular , Saúde da Família , Feminino , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Estrutura Terciária de Proteína , Proteínas/química , Alinhamento de Sequência
18.
Artigo em Inglês | MEDLINE | ID: mdl-21598132

RESUMO

A probabilistic estimation of dietary exposure to cypermethrin residues for the Chinese population was performed. Cypermethrin residue data were obtained from the national food contamination monitoring program for 2001-2006, encompassing 14,096 samples from 36 commodities with a detection rate of 10.4%. Food consumption data were gathered from the national nutrition and health survey conducted in 2002, comprising 65,915 consumers aged 2-100 years and 3701 children of 2-6 years old. The whole country was roughly divided into six regions and the ranges of the median and of P99.9 exposure estimated for these regions were 0.018-0.026 and 3.131-7.095 µg kg(-1 )bw day(-1), respectively. Pak-choi and Chinese cabbage contributed 33.9 and 13.2%, respectively, to the cypermethrin intake for the general population, while pak-choi and citrus covered 30.7 and 22.5% of the total intake for children, respectively. The exposure of the rural population was higher than urban populations. Rural areas mainly located in the plains of central China had among the highest exposure of the six regions, accounting for 17.7% of the ARfD at P99.9, while the 99.99th percentile of exposure for children, especially rural children, far exceeded the ARfD, which is a cause for concern.


Assuntos
Dieta/efeitos adversos , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Criança , Pré-Escolar , China , Feminino , Inocuidade dos Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Inquéritos Nutricionais , Resíduos de Praguicidas/toxicidade , Piretrinas/administração & dosagem , Piretrinas/toxicidade , Medição de Risco , População Rural , População Urbana , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-21598144

RESUMO

This paper compares the exposure for the Chinese populations and sub-groups to acephate, a widely applied organophosphorus pesticide, using deterministic and probabilistic approaches. Acephate residue data were obtained from the national food contamination monitoring program 2001-2006, collected by multi-stage stratified sampling and with a detection rate of 3.3%. Food consumption data were gathered from the national diet and nutrition survey conducted in 2002 over three consecutive days by the 24-h recall method, and included 22,563 families or 65,886 consumers aged 2-100 years. For point estimate, it was evident that exposures were higher than the acute reference dose (ARfD) in many cases. For the probabilistic approach, the P99.9 exposures for the general population and children accounted for 11.88 and 24.15% of the ARfD, respectively, in acute intake calculations and 52.86 and 68.75%, respectively, of the acceptable daily intake (ADI) in chronic intake calculations. The exposure level of rural people was higher than urban dwellers, and vegetables contributed most to acephate intake.


Assuntos
Dieta , Contaminação de Alimentos , Modelos Biológicos , Compostos Organotiofosforados/administração & dosagem , Compostos Organotiofosforados/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Adulto , Criança , China , Bases de Dados Factuais , Humanos , Método de Monte Carlo , Inquéritos Nutricionais , Resíduos de Praguicidas/normas , Fosforamidas , Medição de Risco/métodos , Saúde da População Rural , Saúde da População Urbana , Verduras/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-21181597

RESUMO

Deterministic and probabilistic estimates of the chronic exposure to lead (Pb) for the inhabitants in Jiangsu Province, China, were performed. Pb contamination data were obtained from the national food contamination monitoring programme during 2001-2006 and 2600 samples from 38 commodities in Jiangsu were included. Food consumption data were from the national diet and nutrition survey conducted in 2002, including 3879 subjects aged 2-80 years and 185 children aged 2-6 years in Jiangsu. Contributions from 38 commodities were included in the calculations. Using the provisional tolerable weekly intakes (PTWI) divided into daily intakes (PTWI(d)) of 3.57 microg kg(-1) bw day(-1) in the risk assessment, exposures calculated by the deterministic approach for children and the general population were 77% and 43% of the PTWI(d), respectively, which were nearly similar to the mean intake calculation in the probabilistic approach. The percentage of people whose exposure level exceeded the PTWI(d) for children, the general population, urban population and rural population were 16%, 0.4%, 0.1%, and 0.5%, respectively. The 50th, 95th and 99th percentiles of Pb exposure for children were 2.6, 4.4 and 5.5 microg kg(-1) bw day(-1), respectively. Rice followed by wheat flour and bean products contributed most to the total Pb intake for both children and the general population. This study indicated that the Pb dietary exposure in Jiangsu Province, especially for children, would be a public health concern.


Assuntos
Exposição Ambiental , Chumbo/toxicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China , Humanos , Pessoa de Meia-Idade , Probabilidade , Medição de Risco , Adulto Jovem
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