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1.
Chemosphere ; 364: 143027, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39137867

RESUMO

Membrane filtration is a mainstream method for landfill leachate treatment, leaving the landfill leachate membrane concentrates (LLMCs) a high-toxicity residue. Conventional LLMCs disposal technology shows specific challenges due to the low biodegradability, high inorganic salts, and high heavy metal ions content of LLMCs. Therefore, it is necessary to degrade LLMCs with a more suitable technology. In this study, a special method was proposed to convert some organic chemicals into valuable compounds by aqueous phase reforming (APR). Ni-based catalysts (Ni//La2O3, Ni/CeO2, Ni/MgO, and Ni/Al2O3) were prepared to investigate the effect of different supports on the APR of LLMCs. APR performed outstanding characteristics in the decrease of chemical oxygen demand (COD) and total organic carbon (TOC), the degradation of macromolecules, and the removal of heavy metal ions in the aqueous phase. In addition, H2 was generated which is beneficial for energy compensating during the APR process. The best-performing catalyst (Ni/Al2O3) was selected to investigate the effects of reaction temperature, reaction time, and catalyst addition on product distribution. The optimal H2 selectivity (44.71%) and H2 production (11.63 mmol/g COD) were obtained at 250 °C with 2 g Ni/Al2O3 usage for 1 h. This paper provided a new perspective on the disposal of LLMCs, which will degrade pollutants efficiently.

2.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39082892

RESUMO

With the continuous development of the diamond industry, the China-type cubic press (CCP) has gradually become larger. As a result, the volume of the tungsten carbide (WC) anvil has been increased. Considering that the WC anvil is sintered, a larger volume will deteriorate sintering quality, which could facilitate the formation of cracks during its operation. One feasible way to reduce the volume of the WC anvil is to decrease its diameter and height. Along these lines, in this work, by performing finite element simulations, it was found that a reduction in the diameter of the WC anvil would increase the von Mises stress (VMS) during the synthesis process, as well as reduce the service life of the WC anvil and the ultimate pressure of the CCP. At the same time, a smaller diameter of the WC anvil would cause a significant increase in the VMS of the base steel block, exceeding its yield limit. In addition, a reduction in the height of the WC anvil would lessen the VMS during the synthesis process, and the VMS of the base steel block will also decrease. A reduction in the height of the WC anvil will decrease the pretightening force on the WC anvil, thereby reducing its lateral support effect. When the interference fit was increased from 0.6 to 0.8 mm and the steel ring angle was changed from 1.5° to 1.1°, the pretightening force on the low WC anvil was similar to the pretightening force on the original WC anvil. Our work provides valuable insights for effectively reducing the volume of the WC anvil.

3.
Am J Cancer Res ; 13(9): 4115-4124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818083

RESUMO

In this study, we aim to investigate the role and mechanism of T-box transcription factor 3 (TBX3) in cervical cancer. The mRNA and protein expression of TBX3, inhibitor of DNA binding 1 (ID1), and epithelial mesenchymal transition (EMT) markers (E-Cadherin, N-Cadherin, and vimentin) were measured using qRT-PCR and Western blot. shTBX3 and shID1 were transfected into SiHa cells to knockdown TBX3 and ID1. The metastasis and invasion abilities of cervical cancer cells were determined using a wound healing assay and an invasive assay. The shTBX3- and shID1-transfected SiHa cells were injected into nude mice using a xenograft tumor growth model. We found that TBX3 and ID1 were highly expressed in cervical cancer cells. Importantly, silencing TBX3 and ID1 significantly reduced the migration and metastasis of cervical cancer cells. In addition, silencing TBX3 and ID1 significantly inhibited the EMT, evidenced by the increased E-cadherin, and decreased N-cadherin and vimentin. The size and weight of the xenograft tumor were significantly reduced by shTBX3 and shID1. We demonstrate that TBX3 or ID1 knockdown can effectively inhibit cervical cancer cells migration and invasion. These findings indicate that TBX3 and ID1 can act as potential therapeutic targets for the prevention and treatment of cervical cancer.

4.
Bioresour Technol ; 390: 129846, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820970

RESUMO

Tar problem seriously hinders the development of biomass gasification. The tar formation of biomass is greatly influenced by cellulose. In this work, PY-GC/MS was employed for providing a precise insight into the formation of primary and secondary products, and a tar contribution index was introduced to evaluate the potential of tar formation from different origins. Combined with statistical analysis and corroboration by DFT analysis, key intermediates for tar formation are recognized, and corresponding influence is confirmed. A new framework from cellulose to tar was built. The secondary reaction acts a more important role for tar formation. The aromatic precursors and high-activity small-molecular gases are two key compounds responding to tar formation, and the existence of high-activity small-molecular gases could significantly reduce the energy barrier during tar formation. For furans, the energy barrier can be reduced from 100.2 kcal/mol to 74.2 kcal/mol in the presence of ethylene.


Assuntos
Celulose , Gases , Biomassa
5.
Anticancer Agents Med Chem ; 23(14): 1626-1633, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638593

RESUMO

Background/Introduction: Prostate cancer ranks as the second leading cause of cancer death. No effective pharmacological agent is available for prostate cancer treatment. Berbamine is an alkaloid extracted from the Chinese herb berberis, which exerts an effect on inhibiting cancer cell proliferation. OBJECTIVE: This study aimed to explore the mechanism of berbamine in inhibiting prostate cancer. METHODS: Prostate cancer cell lines PC-3 and DU145 cells were used to evaluate the effects of berbamine. Cell viability was determined using cell-counting kit 8. The intracellular reactive oxygen species (ROS) levels were measured using a ROS assay kit. Cell apoptosis rate was examined using flow cytometry. The protein levels associated with cell proliferation, NF-κB pathway, and apoptosis were determined using western blot. RESULTS: It was found that berbamine induced cell cycle arrest in the S phase and inhibited prostate cancer cell growth and proliferation. Berbamine inhibited prostate cancer cells by inhibiting the activation of the NF-κB pathway in vitro. Berbamine increased ROS as an upstream molecule that inhibited the NF-κB pathway. CONCLUSION: Our results demonstrated that berbamine can effectively reduce the proliferation of prostate cancer cells. The ROS/NF-κB axis plays a crucial role in berbamine-mediated anti-prostate cancer cell proliferation.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Humanos , Masculino , NF-kappa B , Espécies Reativas de Oxigênio , Neoplasias da Próstata/tratamento farmacológico , Próstata
7.
J Chem Phys ; 158(13): 134711, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031159

RESUMO

As an important phase-change material, GeTe has many high-pressure phases as well, but its phase transitions under pressure are still lack of clarity. It is challenging to identify high-pressure GeTe crystal structures owing to the phase coexistence in a wide pressure range and the reversibility of phase transitions. Hence, first-principles calculations are required to provide further information in addition to limited experimental characterizations. In this work, a new orthorhombic Cmca GeTe high-pressure phase has been predicted via the CALYPSO method as the most energetically favorable phase in the pressure range between ∼30 and ∼38.5 GPa, which would update the GeTe high-pressure phase transition sequence. The crystal structure of the Cmca phase is composed of alternate stacking puckered layers of Ge six-membered rings and Te four-membered rings along the b direction. The high density of states near the Fermi level and delocalization of electrons from the two-dimensional electron localization function indicate a strong metallic property of the Cmca phase. Electron-phonon coupling calculations indicate that the Cmca phase is superconductive below ∼4.2 K at 35 GPa. The simulated x-ray diffraction pattern of the Cmca phase implies that this phase might coexist with the Pnma-boat phase under high pressure. These results offer further understanding on the high-pressure structural evolution and physical properties in GeTe and other IV-VI semiconductors.

8.
Front Pharmacol ; 13: 894812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645804

RESUMO

Endotoxins and other harmful substances may cause an increase in permeability in endothelial cells (ECs) monolayers, as well as ECs shrinkage and death to induce lung damage. Lipopolysaccharide (LPS) can impair endothelial progenitor cells (EPCs) functions, including proliferation, migration, and tube formation. EPCs can migrate to the damaged area, differentiate into ECs, and participate in vascular repair, which improves pulmonary capillary endothelial dysfunction and maintains the integrity of the endothelial barrier. Hydrogen (H2) contributes to the repairment of lung injury and the damage of ECs. We therefore speculate that H2 protects the EPCs against LPS-induced damage, and it's mechanism will be explored. The bone marrow-derived EPCs from ICR Mice were treated with LPS to establish a damaged model. Then EPCs were incubated with H2, and treated with PI3K inhibitor LY294002 and endothelial nitric oxide synthase (eNOS) inhibitor L-NAME. MTT assay, transwell assay and tube formation assay were used to detect the proliferation, migration and angiogenesis of EPCs. The expression levels of target proteins were detected by Western blot. Results found that H2 repaired EPCs proliferation, migration and tube formation functions damaged by LPS. LY294002 and L-NAME significantly inhibited the repaired effect of H2 on LPS-induced dysfunctions of EPCs. H2 also restored levels of phosphor-AKT (p-AKT), eNOS and phosphor-eNOS (p-eNOS) suppressed by LPS. LY294002 significantly inhibited the increase of p-AKT and eNOS and p-eNOS expression exposed by H2. L-NAME significantly inhibited the increase of eNOS and p-eNOS expression induced by H2. H2 repairs the dysfunctions of EPCs induced by LPS, which is mediated by PI3K/AKT/eNOS signaling pathway.

9.
Inorg Chem ; 61(21): 8144-8152, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35576525

RESUMO

In recent years, skutterudite filled with electronegative elements (S, Se, Cl, Br) has attracted the extensive attention of researchers. By doping electron donors (Pb, Ni, or Te, S, Se) at the Co or Sb sites, the electronegative elements can form thermodynamically stable compounds in the intrinsic pores of the skutterudite, substantially expanding the research scope of skutterudite. In this study, S0.05Co4Sb11.3Te0.6Se0.1 skutterudite was synthesized at high pressure and high temperature, with a pressure range of 2.0-3.5 GPa. The phase composition, micro-morphology, and electrical and thermal transport properties were systematically characterized. The micromorphology analysis shows that the introduction of S element and substituting Te and Se at the Sb sites inhibit the grain growth in a suitable high-pressure environment. Substantial differences are observed in the directions of the lattice stripes in the samples, and rich grain boundaries and many lattice distortions and dislocation defects occur. The carrier concentration can be optimized by filling the voids of the skutterudite with a few S atoms, and the thermoelectric properties can be optimized by scattering phonons through resonance scattering and defect scattering. The samples synthesized at a pressure of 3.0 GPa and a temperature of 900 K have a maximum power factor of 23.85 × 10-4 W m-1 K-2 and a maximum zT value of 1.30 at a test temperature of 773 K.

10.
Mamm Genome ; 32(5): 371-380, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33993322

RESUMO

Prostate cancer is not easy to metastasize because it is difficult to diagnose at an early stage, and there is no effective treatment currently. miRNA-217-5p has been reported to be a regulator in the process of prostate cancer. This study aimed to investigate how miRNA-217-5p affects the invasion and migration of prostate cancer. Luciferase assay was used to clarify whether the target gene Clusterin (CLU) was interacted directly with miR-217-5p. miR-217-5p and CLU were knocked down by transfecting respective siRNA into DU145 cells. The expression level of epithelial-mesenchymal transition (EMT)-related proteins was detected by Western blotting. Invasion and migration of DU145 cell were examined by wound healing assay. The results showed that miR-217-5p directly interacted with its target gene CLU, and the transfection of si-CLU and si-miR-217-5p had similar ability to regulate the expression level of EMT-related proteins, which in turn affected the migration and invasion of prostate cancer cell line DU145. In addition, miR-217-5p inhibited the expression of EMT-related proteins by regulating the expression of the target gene CLU, and further inhibited the invasion and migration of prostate cancer cells. Our findings provide a theoretical target basis for the treatment of prostate cancer.


Assuntos
Clusterina/metabolismo , MicroRNAs/genética , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Neoplasias da Próstata/patologia , Transição Epitelial-Mesenquimal/genética , Humanos , Masculino
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(1): 181-187, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33554816

RESUMO

OBJECTIVE: To deeply understand the clinical manifestation, laboratory examination characteristics, diagnosis and treatment of an eight p11 myeloproliferative syndrome (EMS) with rare phenotypes. METHODS: The clinical and laboratory characteristics and the process of allogeneic hematopoietic stem cell transplantation (allo-HSCT) were summarized in 1 rare EMS case involving T/B/myeloid cells. Meanwhile, 2 similar cases in the previous literature were also discussed. RESULTS: The bone marrow examination indicated that the patient with B-cell acute lymphocytic leukemia. The lymph node biopsy showed that the patient was T lymphoblastic/myeloid lymphoma. The 8p11 abnormality was found by the examination of bone marrow chromosomes. The RT-PCR examination showed that the BCR-ABL fused gene was negtive. The FGFR1 breakage was found by using the FISH with FGFR1 probe in lymph node. The Mutation of FMNL3, NBPF1 and RUNX1 genes was found by using the whole exome sequencing. The patient received allo-HSCT under CR2. By the follow-up till to September 2019, the patient survived without the above-mentioned disease. CONCLUSION: EMS manifest as neoplasms involving T-lineage, B-lineage, and myeloid-lineage simultaneously is extremely rare. Although the FGFR1 gene-targeted therapy can be conducted, allo-HSCT should be actively considered.


Assuntos
Neoplasias Hematológicas , Transtornos Mieloproliferativos , Medula Óssea , Cromossomos Humanos Par 8 , Forminas , Humanos , Transtornos Mieloproliferativos/genética , Fenótipo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Translocação Genética
12.
Sci Rep ; 10(1): 11416, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651437

RESUMO

Normally, HIV-1 enters into CD4+ cells through membrane fusion, and newly synthesized HIV-1 viral proteins assemble on the plasma membrane to form viral particles and bud out. In the previous study, we found host factor coiled-coil domain containing protein 8 (CCDC8) can strongly inhibit HIV-1 production, but the underline mechanism is not clear. Here we show that overexpression of CCDC8 reverses the normal HIV-1 production process, and causes newly assembled HIV-1 Gag particles to be endocytosed on the plasma membrane, rather than budding out. Live-cell imaging system captured the moment of CCDC8-mediated Gag internalization on the plasma membrane, and the speed of Gag turnover is up to 1.53 µm/s, much faster than Gag assembly on the plasma membrane. After Gag internalization, it accumulates in the cellular organelle-lysosome for degradation, but not proteasome, autophagosome, endoplasmic reticulum, clathrin or recycling endosome. In addition, CCDC8 is a membrane-associated protein, and N-terminal of CCDC8 is very important for membrane binding, and also important for inhibition of Gag assembly. C-terminal deletion of CCDC8 has a little effect on anti-HIV-1 effect. Moreover, CCDC8 is phosphorylated at amino acid threonine T87 and serine S261, and mono-methylated at lysine K491. Alanine mutations of T87A, S261A and K491A singly or in combination do not affect CCDC8 anti-HIV activity. In conclusion, overexpression of CCDC8 can cause newly assembled HIV-1 Gag particles on the plasma membrane to be endocytosed and degraded in lysosome.


Assuntos
Proteínas de Transporte/fisiologia , Lisossomos/metabolismo , Vírion/metabolismo , Montagem de Vírus , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Linfócitos T CD4-Positivos/metabolismo , Membrana Celular/metabolismo , Endocitose , Retículo Endoplasmático/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Soropositividade para HIV , HIV-1/fisiologia , Humanos , Lisina/química , Filogenia , Processamento de Proteína Pós-Traducional
13.
Appl Microbiol Biotechnol ; 104(4): 1545-1553, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897521

RESUMO

Increasing attention has recently been focused on complex symbiotic associations, for instance coral and its symbionts. Sea cucumber, harboring diverse fungi, has also attracted more and more attention for their functional diversity. Here, secondary metabolites produced by Chaetomium globosum associated with sea cucumber, Apostichopus japonicus, were investigated using gene mining with third-generation sequencing technology (PacBio SMRT). Nine compounds, including one new compound cytoglobosin X (1), were isolated from cultures of Chaetomium globosum. Compound 1 was identified based on NMR data, HRESIMS, and ECD, and the absolute configurations were identified as 3S, 4R, 7S, 8R, 9R, 16S, 19S, 20S, and 23S. In an antimicrobial assay, compound 4 showed moderate activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus with MICs of 47.3 and 94.6 µM, respectively. Our results suggest that the microbiomes associated with sea cucumber could be an important resource for biodiversity and structural novelty, and the bioactive compounds may protect the host from pathogen microbial.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Benzopiranos/farmacologia , Chaetomium/química , Alcaloides Indólicos/farmacologia , Pigmentos Biológicos/farmacologia , Stichopus/microbiologia , Animais , Antibacterianos/isolamento & purificação , Benzopiranos/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Alcaloides Indólicos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pigmentos Biológicos/isolamento & purificação , Metabolismo Secundário , Staphylococcus aureus/efeitos dos fármacos , Simbiose
14.
ACS Appl Mater Interfaces ; 12(7): 8271-8279, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31990526

RESUMO

Cu3SbS4-based materials composed of nontoxic, low-cost, and earth-abundant elements potentially exhibit favorable thermoelectric performance. However, some key transport parameters and thermal stability have not been reported. In this work, the effects of Bi and Sn co-doping on thermoelectric properties and the thermal stability of Cu3SbS4 were studied by experiment and theoretical validation. Bi and Sn doping can effectively tune the electrical properties and the electronic band structure. The Bi and Sn doping leads to an increased carrier concentration from 6.4 × 1017 to 7.4 × 1020 cm-3 and a decreased optical band gap from 0.85 to 0.73 eV. The effective mass was increased from ∼3.0 me for Bi-doped samples to ∼4.0 me for Bi and Sn co-doped samples. An enhanced power factor of 1398 µW m-1 K-2 at 623 K was obtained for Cu3Sb1-x-yBixSnyS4 (x = 0.06, y = 0.09). The measurements of elastic properties exhibited a large Grüneisen parameter (γ ∼2) for Cu3SbS4-based materials. Finally, a maximum zT of 0.76 ± 0.02 at 623 K was achieved for Cu3Sb1-x-yBixSnyS4 (x = 0.06, y = 0.05) sample. In addition, Cu3SbS4 materials possess excellent thermal stability after thermal treatment in vacuum at 573 K for totally 500 h and dozens of heating-cooling thermal cycles (300-623-300 K). It indicates that Cu3SbS4 is a robust alternative for Te-free thermoelectric materials at an intermediate temperature range. This work provides feasible guidance to survey the thermal stability of chalcogenides.

15.
Bioresour Technol ; 298: 122263, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31685358

RESUMO

Gasification and pyrolysis have been considered as potential routes for the production of fuel gas from abundant, low-cost and renewable biomass materials. Tar is the undesirable but inevitable byproduct during these processes, which not only lowers the overall energy conversion efficiency but also leads to potential contamination and clogging problems. Catalytic reforming has been seen as one of the most promising methods for tar elimination, and biochar-based nanocatalysts (BBNs) show promise as an efficient tar reforming catalyst. Extensive research efforts have been devoted to the development of BBNs to reduce biomass tar below tolerable limits. This current study reviews the recent progress in the preparation and application of BBNs for converting tar into fuel gas during biomass gasification or pyrolysis. The formation and chemical characteristics of the BBNs are introduced for a better understanding of the catalytic mechanism; prospects for success, as well as challenges, are also discussed.


Assuntos
Gases , Pirólise , Biomassa , Carvão Vegetal
16.
Mol Ther Nucleic Acids ; 12: 267-274, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30195765

RESUMO

C-C chemokine receptor type 5 (CCR5) is the main co-receptor for HIV entry into the target CD4+ cells, and homozygous CCR5Δ32/Δ32 cells are resistant to CCR5-tropic HIV infection. However, the CCR5Δ32/Δ32 homozygous donors in populations are rare. Here we developed a simple approach to induce CCR5Δ32/Δ32 homozygotes through CRISPR-Cas9 genome-editing technology. Designing a pair of single-guide RNA targeting the flank region of the CCR5Δ32 mutation locus, we applied the CRISPR-Cas9 and lentiviral packaging system to successfully convert wild-type CCR5 into CCR5Δ32/Δ32 homozygotes in the human Jurkat CD4+ cell line and primary CD4+ cells, exactly the same as the naturally occurring CCR5Δ32/Δ32 mutation. The successful rate is up to 20% in Jurkat cells but less in primary CD4+ cells. The modified CCR5Δ32/Δ32 CD4+ cells are resistant to CCR5-tropic HIV infection. Whole-genome sequencing revealed no apparent off-target sites. This approach has the promise to promote HIV/AIDS therapy from the only cured unique Berlin patient to a routine autologous cell-based therapy.

17.
Inorg Chem ; 57(11): 6762-6766, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29792420

RESUMO

It has been discussed for a long time that synthetic pressure can effectively optimize thermoelectric properties. The beneficial effect of synthesis pressures on thermoelectric properties has been discussed for a long time. In this paper, it is theoretically and experimentally demonstrated that appropriate synthesis pressures can increase the figure of merit (ZT) through optimizing thermal transport and electronic transport properties. Indium and barium atoms double-filled CoSb3 samples were prepared use high-pressure and high-temperature technique for half an hour. X-ray diffraction and some structure analysis were used to reveal the relationship between microstructures and thermoelectric properties. In0.15Ba0.35Co4Sb12 samples were synthesized by different pressures; sample synthesized by 3 GPa has the best electrical transport properties, and sample synthesized by 2.5 GPa has the lowest thermal conductivity. The maximum ZT value of sample synthesized by 3.0 GPa reached 1.18.

18.
Inorg Chem ; 57(6): 3323-3328, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29494140

RESUMO

The thermoelectric (TE) properties of n-type polycrystalline Yb0.5Ba7.5Ga16Ge30 bulks can be optimized by high-pressure and high-temperature (HPHT) sintering. After HPHT sintering, abundant nanograins are randomly distributed in the sample. Grains are refined by HPHT, with the grains being smaller with higher pressure. In comparison with the arc-melted sample, the samples obtained by quenching under high pressure possess a great number of nanograins and lattice structural disorders. Lower thermal conductivity is benefited by our deliberately engineered microstructures via HPHT, and the minimum thermal conductivity is 0.86 W m-1 K-1 at 773 K. The thermal conductivity and electrical properties are optimized simultaneously by raising the reactive sintering pressure. In comparison with the arc-melted sample (0.56), a maximum zT value of 1.13 at 773 K is obtained for the Yb0.5Ba7.5Ga16Ge30 sample fabricated at 5 GPa. This demonstrates that HPHT provides an effective strategy to improve TE performance through simultaneously enhancing electrical and thermal transport properties and should be applicable to other thermoelectric materials.

19.
Exp Biol Med (Maywood) ; 243(4): 344-349, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29350066

RESUMO

It has been previously suggested that cytokeratins (CKs) are important diagnostic and prognostic biomarkers for urothelial lesions. Hence it is imperative to understand the expression pattern of cytokeratins during formation of papillary bladder cancer, which was the objective of the current study. Expression pattern of CK14 and CK18 were examined using immunohistochemical staining in a mice model of papillary bladder cancer. Twenty female mice were divided into two groups-group 1 (NT) and group 2, which received N-butyl- N-(4-hydroxybutyl) nitrosamine (BBN) for 20 weeks plus one week without treatment. Following histological classification of bladder lesions, CK14 and CK18 immunostaining was assessed according to its distribution and intensity. In NT animals, both basal cells and umbrella cells showed sporadic positive staining for CK14 and CK18, respectively. In BBN group, hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining ( P < 0.05 in each case). Invasive carcinomas showed increased CK14 immunostaining in all epithelial layers. Cumulatively, our data indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis in females at least and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions. Impact statement Studies have shown that expression of cytokeratins (CKs) or their altered distribution affects the bladder cancer pathogenesis and disease outcome, while the underlying mechanisms are not clear. The present study aims to explore the expression pattern of CK14 and CK18 during formation of papillary bladder cancer. The results showed that hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining and invasive carcinomas showed increased CK14 immunostaining in all epithelial layers in N-butyl- N-(4-hydroxybutyl)nitrosamine (BBN)-induced mouse model. The results indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions, which may provide the early diagnosis index.


Assuntos
Carcinoma Papilar/patologia , Queratina-14/análise , Queratina-18/análise , Lesões Pré-Cancerosas/patologia , Neoplasias da Bexiga Urinária/patologia , Animais , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Camundongos Endogâmicos C57BL
20.
Inorg Chem ; 56(18): 11275-11281, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28853562

RESUMO

We developed suitable high-pressure and high-temperature (HPHT) conditions for improvement of the thermoelectric properties of nonstoichiometric TiO1.80. X-ray diffraction, scanning transmission microscopy, transmission electron microscopy, and ultraviolet spectral measurements demonstrate that the crystal structures and microstructures are strongly modulated by our HPHT. The electrical properties and thermal conductivity are improved simultaneously by raising the reactive sintering pressure. The band gap was narrowed, contributing to the increase of the electrical properties with the pressure. In addition, relatively low thermal conductivities were obtained here as a result of a full spectrum of phonon scattering, benefiting from our deliberately engineered microstructures via HPHT. As a consequence, a high dimensionless figure of merit (zT) of 0.36 was obtained at 700 °C in the sample fabricated at 5 GPa. As far as we know, this is higher than all of the results of nonstoichiometric titanium oxide by other means and an enhancement of 57% of the best ever result. HPHT offers us a promising alternative for optimization of the thermoelectric properties, and it is worthwhile to popularize it.

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