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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 778-790, 2024 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-38955724

RESUMO

Objective: To investigate the effects of subcutaneous immunotherapy (SCIT) on patients' immune markers and metabolic levels in the early stage of allergen treatment, and to gain insight into the role of SCIT in regulating immune responses and metabolic levels, so as to provide reference data for the further discovery of potential biomarkers. Methods: A longitudinal study was used to include 40 subjects who underwent SCIT with dust mite allergens in the Department of Pediatrics of the First Affiliated Hospital of Guangzhou Medical University between November 2017 and February 2022, including 20 subjects each of single mite subcutaneous immunotherapy (SM-SCIT) and double mite subcutaneous immunotherapy (DM-SCIT). In this study, levels of dust mite allergen-specific antibodies and polyunsaturated fatty acid metabolism were measured before and 12 months after treatment, while pulmonary function tests were performed. The therapeutic effects of the patients were followed up by visual analogue scale (VAS), asthma control test (ACT) and total medication scores (TMS). The results were statistically analyzed using t-test and Mann-Whitney U-test. Results: After 12 months of treatment with SCIT, both groups showed a significant decrease in total VAS score (SM-SCIT:Z=-2.298, P<0.05; DM-SCIT:Z=-3.411, P<0.001); total ACT score (SM-SCIT:Z=-2.054, P<0.05; DM-SCIT:Z=-2.014, P<0.05) and total medication scores (SM-SCIT:Z=-3.799, P<0.000 1; DM-SCIT:Z=-3.474, P<0.001) were significantly higher, in addition to significantly higher MMEF75/25 values in the DM-SCIT group (t=-2.253, P<0.05). There was no significant change in sIgE in the SM-SCIT group (P>0.05), and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 2, and p 21 fractions were significantly elevated (Z=-2.651, -3.771, -2.949, -2.912, -2.725, -2.128, and -3.285, respectively, all P<0.05); The sIgE of Der p 2, f 2, p 7 and p 23 fractions(Z=-2.651, -3.771, -2.949, -2.912, -2.725, -2.128, -3.285, all P<0.05) and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 1, f 2, p 10, p 21 and p 23 fractions (Z=-3.808, -3.845, -3.061, -2.688, -2.464, -3.211, -2.371, -2.091, -2.427, all P<0.05) of the DM-SCIT group were significantly elevated. Metabolomics analysis showed that arachidonic acid, docosahexaenoic acid, docosapentaenoic acid, eicosapentaenoic acid, 5, 9, 12-octadecatrienoic acid, 5(S)-hydroxylated eicosatetraenoic acid, and dihomo-gamma-linolenic acid were significantly elevated at the beginning of the treatment period after SM-SCIT treatment (Z of -2.191, -2.497, -1.988, -2.090, -2.19, -2.803, -2.073, all P<0.05); 5(S)-hydroxylated eicosatetraenoic acid showed elevated and alpha-linolenic acid, eicosadienoic acid, and eicosapentaenoic acid were significantly decreased in the DM-SCIT group after treatment (Z=-1.988, -2.090, -2.497, -1.988, respectively, all P<0.05). Correlation analysis showed that arachidonic acid was significantly negatively correlated with changes in dust mite-specific IgG4 (r=-0.499, P<0.05), and that alpha-linolenic acid, 5, 9, 12-octadecatrienoic acid, and eicosapentaenoic acid were positively correlated with the ΔsIgG4 of the dust mite der p 2 (r=0.451, 0.420, 0.474, respectively; all P<0.05). Conclusion: Significant changes in allergen-specific antibody levels and polyunsaturated fatty acid metabolism levels occur during SCIT, and the two may interact and influence each other.


Assuntos
Asma , Dessensibilização Imunológica , Ácidos Graxos Insaturados , Humanos , Animais , Dessensibilização Imunológica/métodos , Asma/terapia , Pyroglyphidae/imunologia , Estudos Longitudinais , Antígenos de Dermatophagoides/imunologia , Alérgenos/imunologia , Criança , Injeções Subcutâneas , Imunoglobulina E/imunologia
2.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(1): 38-43, 2023 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-36718687

RESUMO

OBJECTIVE: To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules. METHODS: Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma. RESULTS: The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600µm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure. CONCLUSION: Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.


Assuntos
Hidróxido de Cálcio , Clorexidina , Clorexidina/farmacologia , Hidróxido de Cálcio/farmacologia , Enterococcus faecalis/fisiologia , Temperatura , Dentina , Biofilmes , Antibacterianos/farmacologia , Irrigantes do Canal Radicular/farmacologia , Cavidade Pulpar
3.
Proc Natl Acad Sci U S A ; 115(21): 5392-5396, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29735712

RESUMO

A central mystery in high-temperature superconductivity is the origin of the so-called strange metal (i.e., the anomalous conductor from which superconductivity emerges at low temperature). Measuring the dynamic charge response of the copper oxides, [Formula: see text], would directly reveal the collective properties of the strange metal, but it has never been possible to measure this quantity with millielectronvolt resolution. Here, we present a measurement of [Formula: see text] for a cuprate, optimally doped Bi2.1Sr1.9CaCu2O8+x (Tc = 91 K), using momentum-resolved inelastic electron scattering. In the medium energy range 0.1-2 eV relevant to the strange metal, the spectra are dominated by a featureless, temperature- and momentum-independent continuum persisting to the electronvolt energy scale. This continuum displays a simple power-law form, exhibiting q2 behavior at low energy and q2/ω2 behavior at high energy. Measurements of an overdoped crystal (Tc = 50 K) showed the emergence of a gap-like feature at low temperature, indicating deviation from power law form outside the strange-metal regime. Our study suggests the strange metal exhibits a new type of charge dynamics in which excitations are local to such a degree that space and time axes are decoupled.

4.
Zhonghua Bing Li Xue Za Zhi ; 50(10): 1139-1144, 2021 Oct 08.
Artigo em Zh | MEDLINE | ID: mdl-34619867

RESUMO

Objective: To investigate the clinicopathological features and prognostic factors of primary mediastinal large B-cell lymphoma (PMBL). Methods: The clinical data of 60 patients with PMBL including 44 biopsy cases and 16 consultation cases from September 2000 to November 2019 in the Department of Pathology, China-Japan Friendship Hospital (14 cases) and Peking Union Medical College Hospital (46 cases) were enrolled. Pathologic features, immunophenotype, immunoglobulin (Ig) gene rearrangement and microRNA expression profile were retrospectively studied. Results: Of the 60 patients, 23 were males and 37 were females, age ranged from 15 to 64 years (median 28 years). Immunohistochemical staining showed that the tumor cells were positive for pan-B cell antigens, CD30 (77.4%, 24/31), CD23 (73.1%, 19/26), MUM1 (45.8%, 11/24), Ki-67 index ≥70 % (90.6%, 29/32). EBER in situ hybridization was analyzed in 21 PMBL, only one case (4.8%) was positive. Ig gene rearrangement was performed in 20 cases, and seven were positive (35.0%). MicroRNA gene expression profiles were analyzed in seven cases of PMBL and nine cases of diffuse large B-cell lymphoma, and there were 33 microRNAs with significant difference (P<0.05). Univariate analysis indicated that the poor prognostic factors included serum lactate dehydrogenase (LDH) level,International Prognostic Index (IPI) score ≥3, stages Ⅲ-Ⅳ, chemotherapy not combined with rituximab and MUM1 positivity (P<0.05). Multivariate analysis showed that the treatment combined with rituximab was independently related to prognosis (P<0.05). Conclusions: PMBL is different from diffuse large B-cell lymphoma in clinicopathologic features, immunophenotypic presentation and molecular features. The prognostic factors, molecular genetics and immunological characteristics reveal that this study has enriched our understanding of the biology of PMBL, thus providing evidence and strategies for treatment.


Assuntos
Linfoma Difuso de Grandes Células B , Neoplasias do Mediastino , MicroRNAs , Adolescente , Adulto , Feminino , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Masculino , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias do Mediastino/genética , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
5.
Proc Natl Acad Sci U S A ; 114(5): 816-821, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28096330

RESUMO

Three-dimensional topological insulators (3D TIs) represent states of quantum matters in which surface states are protected by time-reversal symmetry and an inversion occurs between bulk conduction and valence bands. However, the bulk-band inversion, which is intimately tied to the topologically nontrivial nature of 3D Tis, has rarely been investigated by experiments. Besides, 3D massive Dirac fermions with nearly linear band dispersions were seldom observed in TIs. Recently, a van der Waals crystal, ZrTe5, was theoretically predicted to be a TI. Here, we report an infrared transmission study of a high-mobility [∼33,000 cm2/(V ⋅ s)] multilayer ZrTe5 flake at magnetic fields (B) up to 35 T. Our observation of a linear relationship between the zero-magnetic-field optical absorption and the photon energy, a bandgap of ∼10 meV and a [Formula: see text] dependence of the Landau level (LL) transition energies at low magnetic fields demonstrates 3D massive Dirac fermions with nearly linear band dispersions in this system. More importantly, the reemergence of the intra-LL transitions at magnetic fields higher than 17 T reveals the energy cross between the two zeroth LLs, which reflects the inversion between the bulk conduction and valence bands. Our results not only provide spectroscopic evidence for the TI state in ZrTe5 but also open up a new avenue for fundamental studies of Dirac fermions in van der Waals materials.

6.
Zhonghua Yi Xue Za Zhi ; 100(15): 1142-1147, 2020 Apr 21.
Artigo em Zh | MEDLINE | ID: mdl-32311877

RESUMO

Objective: To analyze whether there is a difference in the influence of coronary artery disease (CAD) on the clinical features and prognosis of three different types of heart failure patients. Methods: Complete clinical data of 1 520 hospitalized patients with heart failure from Tianjin Medical University General Hospital and Tianjin Chest Hospital from March 2014 to February 2016 was retrospectively reviewed. According to left ventricular ejection fraction (LVEF), the patients were divided into three groups: heart failure with reduced ejection fraction group (HFrEF), heart failure with mid-range ejection fraction group (HFmrEF)and heart failure with preserved ejection fraction group (HFpEF). Each group was further classified into two subgroups according to absence or presence of CAD (No CAD' and 'With CAD'). In the HFrEF group, 197 patients were categorized into 'No CAD' sub-group while 435 patients were into 'With CAD' sub-group. Likewise, 63 patients in HFmrEF group fell into 'No CAD' sub-group while 367 were into 'With CAD' sub-group. Seventy two patients in the HFpEF group were in the 'No CAD' sub-group with 386 in the 'With CAD' sub-group. Clinical features and 2-year prognosis between different subgroups were compared. Results: (1) The relationship between CAD and clinical features of different types of heart failure: the proportions of HFrEF, HFmrEF and HFpEF combined with CAD were 68.8%, 85.3% and 84.3%, respectively (P<0.05). Compared with the 'No CAD' subgroups, patients in the 'With CAD' subgroups were older, and had higher NT-proBNP levels, higher rates of hypertension and diabetes, and lower rates of atrial fibrillation. Also, there were more use of antiplatelet and nitrate drugs in the 'With CAD' sub-groups (P<0.05). (2) Risk of different types of heart failure combined with CAD: after multivariate adjustment, HFrEF had a lower risk of CAD (HFrEF vs HFmrEF: RR=0.389, 95%CI 0.281-0.540; HFrEF vs HFpEF: RR=0.408, 95%CI 0.298-0.560). (3)The influence of CAD on the prognosis of different types of heart failure: CAD increased the risk of mortality in the HFrEF group (HR=1.631, 95%CI 1.119-2.377), and cardiovascular events in all three types of heart failure (HR: HFrEF 1.725, 95%CI 1.325-2.246; HFmrEF 1.815, 95%CI 1.144-2.879; HFpEF 1.900, 95%CI 1.218-2.963). Conclusions: Patients with HFmrEF and HFpEF have a higher prevalence and risk of CAD than patients with HFrEF. CAD is associated with an increased risk of cardiovascular events in all types of heart failure and increases the risk of all-cause mortality among HFrEF group. CAD is an important factor influencing the clinical features and prognosis of patients with all types of heart failure.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Humanos , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
7.
Nat Mater ; 17(5): 416-420, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29610487

RESUMO

The possibility of driving phase transitions in low-density condensates through the loss of phase coherence alone has far-reaching implications for the study of quantum phases of matter. This has inspired the development of tools to control and explore the collective properties of condensate phases via phase fluctuations. Electrically gated oxide interfaces1,2, ultracold Fermi atoms3,4 and cuprate superconductors5,6, which are characterized by an intrinsically small phase stiffness, are paradigmatic examples where these tools are having a dramatic impact. Here we use light pulses shorter than the internal thermalization time to drive and probe the phase fragility of the Bi2Sr2CaCu2O8+δ cuprate superconductor, completely melting the superconducting condensate without affecting the pairing strength. The resulting ultrafast dynamics of phase fluctuations and charge excitations are captured and disentangled by time-resolved photoemission spectroscopy. This work demonstrates the dominant role of phase coherence in the superconductor-to-normal state phase transition and offers a benchmark for non-equilibrium spectroscopic investigations of the cuprate phase diagram.

8.
Phys Rev Lett ; 122(21): 217402, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31283333

RESUMO

Zirconium pentatelluride was recently reported to be a 3D Dirac semimetal, with a single conical band, located at the center of the Brillouin zone. The cone's lack of protection by the lattice symmetry immediately sparked vast discussions about the size and topological or trivial nature of a possible gap opening. Here, we report on a combined optical and transport study of ZrTe_{5}, which reveals an alternative view of electronic bands in this material. We conclude that the dispersion is approximately linear only in the a-c plane, while remaining relatively flat and parabolic in the third direction (along the b axis). Therefore, the electronic states in ZrTe_{5} cannot be described using the model of 3D Dirac massless electrons, even when staying at energies well above the band gap 2Δ=6 meV found in our experiments at low temperatures.

9.
Ann Oncol ; 29(3): 632-639, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29267898

RESUMO

Background: MYC is a well-established cancer driver gene regulating the expression of numerous genes, indicating that polymorphisms in MYC response elements could affect tumorigenesis through altering MYC regulation. We performed integrative multistage study to evaluate the effects of variants in MYC response elements and colorectal cancer (CRC) risk. Patients and methods: We systematically integrated ChIP-Seq, DNase-Seq and transcription factor motif data to screen variants with potential ability to affect the MYC binding affinity. Then, we conducted a two-stage case-control study, totally consisting of 4830 CRC cases and 4759 controls in Chinese population to identify risk polymorphisms and interactions. The effects of risk variants were confirmed by functional assays in CRC LoVo, SW480 and HCT15 cells. Results: We identified a novel polymorphism rs11777210 in KBTBD11 significantly associated with CRC susceptibility (P = 2.43 × 10-12). Notably, we observed a significant interaction between rs11777210 and MYC nearby rs6983267 (P-multi = 0.003, P-add = 0.005), subjects carrying rs6983267 GG and rs11777210 CC genotypes showing higher susceptibility to CRC (2.83-fold) than those carrying rs6983267 TT and rs11777210 TT genotypes. We further demonstrated that rs6983267 T > G increased MYC expression, and MYC bound to and negatively regulated KBTBD11 expression when the rs11777210 C risk allele was present. KBTBD11 was downregulated in tumor tissues, and KBTBD11 knockdown promoted cell proliferation and inhibited cell apoptosis. Conclusion: The rs11777210 is a potential predictive biomarker of CRC susceptibility, and KBTBD11 functions as a putative tumor suppressor in tumorigenesis. Our study highlighted the high CRC risk of people carrying rs6983267 G and rs11777210 C alleles, and provided possible biological mechanism of the interaction.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença/genética , Proteínas Proto-Oncogênicas c-myc/genética , Elementos de Resposta/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
10.
Am J Transplant ; 17(1): 81-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27273890

RESUMO

Recent clinical studies suggest that operational allograft tolerance can be persistent, but long-term surviving allografts can be rejected in a subset of patients, sometimes after episodes of infection. In this study, we examined the impact of Listeria monocytogenes (Lm) infection on the quality of tolerance in a mouse model of heart allograft transplantation. Lm infection induced full rejection in 40% of tolerant recipients, with the remaining experiencing a rejection crisis or no palpable change in their allografts. In the surviving allografts on day 8 postinfection, graft-infiltrating cell numbers increased and exhibited a loss in the tolerance gene signature. By day 30 postinfection, the tolerance signature was broadly restored, but with a discernible reduction in the expression of a subset of 234 genes that marked tolerance and was down-regulated at day 8 post-Lm infection. We further demonstrated that the tolerant state after Lm infection was functionally eroded, as rejection of the long-term surviving graft was induced with anti-PD-L1 whereas the same treatment had no effect in noninfected tolerant mice. Collectively, these observations demonstrate that tolerance, even if initially robust, exists as a continuum that can be eroded following bystander immune responses that accompany certain infections.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Listeria monocytogenes/imunologia , Listeriose/imunologia , Tolerância ao Transplante/imunologia , Animais , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/virologia , Listeriose/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante Homólogo
11.
J Anim Physiol Anim Nutr (Berl) ; 101(5): e312-e322, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28063189

RESUMO

To determine the effects of different sources of protein on the growth performance of newly weaned piglets, 72 newly weaned piglets were randomly assigned to three groups fed different diets (soya bean, casein and dried distillers' grain with solubles (DDGS) feeds). Casein and DDGS feeds consisted of soya bean feed in which 5% of the CP was replaced with casein- or DDGS-derived CP respectively. Blood and chyme samples were collected from each piglet 2 h post-feeding on days 0 and 28 of the feeding period. The DDGS feed decreased DMI (p = 0.024) and increased FCR (p = 0.025) due to lower nitrogen utilization (p = 0.078) than those of other feeds. Total amino acid content in chyme demonstrated that casein feed digested rapidly in the duodenum (p = 0.005), whereas DDGS feed was digested primarily in the distal jejunum (p = 0.003) and ileocecum (p = 0.002). However, polypeptide profiles in chyme exhibited a pattern different from those of amino acids. There were no differences in the polypeptide profiles in the stomachs of piglets fed soya bean or casein feeds (p > 0.05), but soya bean group had greater amounts of small polypeptides (mass under m/z 3000 Da) in the duodenum (p = 0.052) than other groups. In contrast, the DDGS feed group had more large polypeptides (m/z 3000-4000 Da) in the stomach than the other groups (p < 0.001). In addition, 10 pairs of polypeptides with matching masses were identified in the plasma and digesta, indicating that polypeptides may have been transported across the intestinal epithelial cells and into the blood. Taken together, substitution of 5% of the CP in soya bean meal-based feed with DDGS-derived CP decreased the growth performance of newly weaned piglets due to poor digestibility and N utilization of DDGS feed, as well as untimely digestion of casein feed.


Assuntos
Ração Animal/análise , Proteínas Alimentares/farmacologia , Conteúdo Gastrointestinal/química , Peptídeos/sangue , Suínos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Glicemia , Proteínas Sanguíneas , Nitrogênio da Ureia Sanguínea , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Quimotripsina/química , Quimotripsina/metabolismo , Dieta/veterinária , Proteínas Alimentares/metabolismo , Masculino , Nitrogênio , Pepsina A/química , Pepsina A/metabolismo , Glycine max , Triglicerídeos/sangue , Tripsina/química , Tripsina/metabolismo , Desmame
12.
Clin Exp Obstet Gynecol ; 44(3): 496-498, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29949307

RESUMO

PURPOSE: Fetal immature mediastinal teratoma is a rare disease. The pressure generated by the tumor mass can cause hydrops fetalis, pulmonary hypoplasia, pleural and peritoneal effusion, and polyhydramnios which cause the death of the fetus. Routine prenatal ultrasound has enabled accurate diagnosis. MATERIALS AND METHODS: The authors report a 26-year-old patient, gravida 4 para 1, who was referred to this hospital, carrying a fetus with immature mediastinal teratoma. RESULTS: At 27 weeks of gestation, a routine prenatal ultrasound suggested the fetus had a mass at the anterior mediastinum, accompanied by pulmonary hypoplasia, pleural and peritoneal effusion, subcutaneous edema of head and chest, and polyhydramnios. After the therapeutic abortion, the gross anatomy confirmed the mediastinal mass. The histological examination showed that the mass was a grade 2 immature teratoma. CONCLUSIONS: The mother of the fetus had been exposed to plaster, paint, and paint-thinner in the first trimester of pregnancy, suggesting that these chemical contacts may be one of the causes of the disorder.


Assuntos
Doenças Fetais/diagnóstico por imagem , Doenças Fetais/patologia , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/patologia , Teratoma/diagnóstico por imagem , Teratoma/patologia , Aborto Terapêutico , Adulto , Feminino , Número de Gestações , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Diagnóstico Pré-Natal
13.
Phys Rev Lett ; 115(25): 257402, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26722943

RESUMO

We used low-energy, momentum-resolved inelastic electron scattering to study surface collective modes of the three-dimensional topological insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}. Our goal was to identify the "spin plasmon" predicted by Raghu and co-workers [Phys. Rev. Lett. 104, 116401 (2010)]. Instead, we found that the primary collective mode is a surface plasmon arising from the bulk, free carriers in these materials. This excitation dominates the spectral weight in the bosonic function of the surface χ^{"}(q,ω) at THz energy scales, and is the most likely origin of a quasiparticle dispersion kink observed in previous photoemission experiments. Our study suggests that the spin plasmon may mix with this other surface mode, calling for a more nuanced understanding of optical experiments in which the spin plasmon is reported to play a role.

14.
Phys Rev Lett ; 114(14): 147001, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910152

RESUMO

We report a fine tuned doping study of strongly overdoped Bi_{2}Sr_{2}CaCu_{2}O_{8+δ} single crystals using electronic Raman scattering. Combined with theoretical calculations, we show that the doping, at which the normal-state pseudogap closes, coincides with a Lifshitz quantum phase transition where the active holelike Fermi surface becomes electronlike. This conclusion suggests that the microscopic cause of the pseudogap is sensitive to the Fermi surface topology. Furthermore, we find that the superconducting transition temperature is unaffected by this transition, demonstrating that their origins are different on the overdoped side.

15.
Genet Mol Res ; 14(3): 9261-8, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26345859

RESUMO

Previous studies have shown that genetic polymorphisms in exon7 of the NSUN7 gene can be used as an infertility marker in Iranian men with asthenospermia. However, there have been no equivalent studies in China. In the present study, we investigated the possible association between the genetic polymorphisms in exon7 of NSUN7 and asthenospermia in a Chinese Han population. We recruited 240 asthenospermic men as a patient group and 256 normospermic men as a control group, and analyzed the semen parameters on the basis of World Health Organization (WHO) guidelines. The genetic polymorphisms in exon7 of NSUN7 were detected by DNA sequence analysis. The results were analyzed statistically and a P value < 0.05 was considered significant. There were two genetic polymorphisms, c.906C>T and c.922T>G, in exon7 of NSUN7. We found relatively similar genotypes and allele frequencies between the two groups (P = 0.928, P = 0.928, respectively). The combined genotypes of the two polymorphisms did not identify a haplotype associated with asthenospermia (P = 0.824, P = 0.824, respectively). Our findings revealed that genetic polymorphisms in exon7 of the NSUN7 gene are not associated with asthenospermia in Chinese Han men.


Assuntos
Povo Asiático/genética , Astenozoospermia/genética , Éxons , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , China , Frequência do Gene , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Adulto Jovem
16.
Genet Mol Res ; 14(2): 3491-500, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25966116

RESUMO

We examined the association between the methionine synthase reductase (MTRR A66G), methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), and methionine synthase (MS A2756G) genotypes and non-obstructive male infertility in a Chinese population. This case-control study included 162 infertile Chinese patients with azoospermia (N = 100) or oligoasthenozoospermia (N = 62) and 120 fertile men as controls. The polymorphisms MTRR A66G, MTHFR C677T, A1298C, and MS A2756G were identified by direct DNA sequencing and the results were statistically analyzed. We found no association between the incidence of any of these variants in azoospermia patients and control populations. The frequency of the MTRR66 polymorphic genotypes (AG, AG+GG) was significantly higher in the oligoasthenozoospermia group compared to the controls (P = 0.013, 0.012). Our findings revealed an association between the single-nucleotide polymorphism A66G in the MTRR gene and male infertility, particularly in oligoasthenozoospermia males, suggesting that this polymorphism is a genetic risk factor for male infertility in Chinese men.


Assuntos
Ferredoxina-NADP Redutase/genética , Predisposição Genética para Doença/genética , Infertilidade Masculina/genética , Polimorfismo de Nucleotídeo Único , Alelos , Povo Asiático/genética , Azoospermia/etnologia , Azoospermia/genética , Sequência de Bases , Estudos de Casos e Controles , China , Análise Mutacional de DNA , Frequência do Gene , Predisposição Genética para Doença/etnologia , Genótipo , Humanos , Infertilidade Masculina/etnologia , Masculino
17.
Insect Mol Biol ; 23(2): 216-29, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24330037

RESUMO

The citrus red mite (Panonychus citri) can feed on more than 112 plant species around the world. Endogenous small RNAs (sRNAs) have proved to be important components of gene regulation in many eukaryotes. Recently, many sRNAs have been shown to be involved in various biological processes, such as development in many animals, including insects; however, to date, no sRNAs have been reported in the citrus red mite. Using Illumina sequencing, several categories of sRNAs were identified, including 594 known microRNAs (miRNAs) grouped into 206 families and 31 novel miRNAs in the four developmental stages of citrus red mite. In addition, according to bioinformatics analysis and S-Poly(T) miRNA assays, the expression level of many miRNAs varied among the developmental stages. Furthermore, the prediction of miRNAs target genes and their functional annotation indicated that miRNAs are involved in the regulation of multiple pathways in the citrus red mite. As the first report of the sRNA world in citrus red mite, the present study furthers our understanding of the roles played by sRNAs in the development of citrus red mite and the data may help to develop methods of controlling the pests in the field.


Assuntos
MicroRNAs/genética , Tetranychidae/genética , Transcriptoma , Animais , Feminino , Larva/genética , Larva/metabolismo , MicroRNAs/metabolismo , Dados de Sequência Molecular , Ninfa/genética , Ninfa/metabolismo , Óvulo/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Tetranychidae/crescimento & desenvolvimento , Tetranychidae/metabolismo
18.
Phys Rev Lett ; 113(9): 096401, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25215996

RESUMO

The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se (x=0.00, 0.15, and 0.23). The results of infrared measurements as a function of pressure indicate the closing and the reopening of the band gap as well as a maximum in the free carrier spectral weight. The enhanced density of states near the band gap in the topological phase gives rise to a steep interband absorption edge. The change of density of states also yields a maximum in the pressure dependence of the Fermi level. Thus, our conclusive results provide a consistent picture of pressure-induced topological phase transitions and highlight the bulk origin of the novel properties in topological insulators.

19.
Chemphyschem ; 15(10): 1956-69, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25044525

RESUMO

Developing a stable and safe electrolyte that works at voltages as high as 5 V is a formidable challenge in present Li-ion-battery research because such high voltages are beyond the electrochemical stability of the conventional carbonate-based solvents available. In the past few years, extensive efforts have been carried out by the research community toward the exploration of high-voltage electrolytes. In this review, recent progress in the study of several promising high-voltage electrolyte systems, as well as their recipes, electrochemical performance, electrode compatibility, and characterization methods, are summarized and reviewed. These new electrolyte systems include high-voltage film-forming additives and new solvents, such as sulfones, ionic liquids, nitriles, and fluorinated carbonates. It appears to be very difficult to find a good high-voltage (∼5 V) electrolyte with a single-component solvent at the present stage. Using mixed fluorinated-carbonate solvents and additives are two realistic solutions for practical applications in the near term, while sulfones, nitriles, ionic liquids and solid-state electrolyte/polymer electrolytes are promising candidates for the next generation of high-voltage electrolyte systems.

20.
Parasite Immunol ; 36(2): 100-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24558656

RESUMO

Direct inhibitory effects of tannic acid on Haemonchus contortus viability were studied in vitro using the larval migration inhibition (LMI) assay. Sheep white blood cells (WBC) were preincubated with 5 and 50 lg/mL tannic acid or not followed by whole H. contortus antigen (WHA). Cells were harvested at 24 h post-incubation to test host immune responses. Concentrations of 50, 100, 500, 1000, 3000 and 5000 lg/mL tannic acid inhibited larvae migration by 19.8, 42.4, 46.3, 92.0, 93.7 and 100%, respectively, within 96 h post-incubation (P < 0.001). The relative mRNA levels of interferon (IFN)-c, interleukin (IL)-2, IL-4 and IL-10 were increased by WHA stimulation without tannic acid. However, the increased effects on IFN-c and IL-2 were inhibited by tannic acid preincubation (P < 0.001), while the increases in IL-4 and IL-10 were greatly enhanced by tannic acid preincubation (P < 0.001). Changes in protein levels of all cytokines essentially paralleled the changes in their corresponding mRNA levels. In conclusion, tannic acid is directly harmful to larvae in a dose- and time-dependent manner and modulates immune responses of sheep WBC stimulated by H. contortus antigen by inhibiting Th1 cytokines and increasing Th2 cytokine expression in vitro.


Assuntos
Antígenos de Helmintos/imunologia , Citocinas/biossíntese , Haemonchus/efeitos dos fármacos , Haemonchus/imunologia , Leucócitos/imunologia , Ovinos/imunologia , Taninos/farmacologia , Animais , Proliferação de Células , Citocinas/imunologia , Haemonchus/fisiologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Interleucina-2/biossíntese , Interleucina-2/imunologia , Interleucina-4/biossíntese , Interleucina-4/imunologia , Larva/imunologia , Masculino
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