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1.
Artigo em Zh | MEDLINE | ID: mdl-37667154

RESUMO

Objective: To analyze the clinicopathological characteristics of diffuse malignant pleural mesothelioma (MPM), and explore the diagnostic methods in order to improve the early diagnosis rate. Methods: In January 2019 to January 2022, the clinical features, auxiliary examination and immunohistochemical results of 68 cases of MPM were analyzed retrospectively. The pathogenic features, histopathological morphology and the expression of related antibodies including Calretinin (CR), D2-40 and WT-1 were summarized. Results: Among the 68 patients, 40 male (58.82%), 28 female (41.18%), male to female ratio was 1.43%, median age was 58 years old; 50% of patients in Dayao County, epithelial mesothelioma 59 cases (86.76%), occurred in right chest in 39 cases (57.35%), left chest in 25 cases (36.76%), and 4 cases in both sides (5.89%). The most common initial clinical manifestations were pleural effusion (95.59%), chest pain (36.75%), chest tightness and shortness of breath (30.88%). The main imaging findings were pleural effusion in 49 cases (98.00%) and pleural thickening in 46 cases (92.00%). MPM tumor cells often expressed Calretinin, CK5/6, WT1 and D2-40, while TTF-1, NapsinA and CEA, the main markers differentiated from lung adenocarcinoma were negative. Serum CYFRA21-1 and CEA have high value in differential diagnosis of benign and malignant pleural effusions. Conclusion: Diffuse MPM has diverse histological and cytological morphology, which needs to be differentiated from a variety of diseases. Correct diagnosis of diffuse MPM through immunohistochemistry requires the combined application of a group of Mesothelium related antibodies.


Assuntos
Mesotelioma Maligno , Derrame Pleural , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Calbindina 2 , Estudos Retrospectivos
2.
Phys Chem Chem Phys ; 24(8): 4925-4934, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35137749

RESUMO

A series of polycrystalline NiCr2-xAlxO4 (0.1 ≤ x ≤ 0.25) spinel ceramics have been synthesized using a sol-gel method. DC magnetization measurements are carried out at different temperatures and magnetic fields. A novel magnetization reversal has been observed in the field cooling process for the x = 0.2 sample, which can be ascribed to the competition between two magnetic sublattices due to their different temperature dependences. The magnetic interaction evolution, related to the complex magnetic properties, is revealed by exchange constants that have been estimated according to ferrimagnetic Curie-Weiss fitting and mean field theory. The fitting result confirmed the evolution of antiferromagnetic and ferromagnetic components with Al substitution, which is supported by the observations from the isothermal magnetization measurements. The positive and negative values of the magnetic moment can be utilized for storage applications based on the results of magnetic switching effect measurements.

3.
Zhonghua Yi Xue Za Zhi ; 102(20): 1518-1522, 2022 May 31.
Artigo em Zh | MEDLINE | ID: mdl-35692067

RESUMO

Objective: To explore the value of low-dose indocyanine green (ICG) fluorescence imaging in laparoscopic cholecystectomy (LC) for acute cholecystitis. Methods: Clinical data of 198 patients with acute cholecystitis and had received LC in Changzhou No.2 People's Hospital from January 2020 to September 2021 were collected. In the fluorescence group (n=97), peripheral intravenous injection of ICG was performed 15 minutes before LC, while conventional white light was applied in the control group (n=101). The efficiency of bile duct discrimination, operation time, intraoperative bleeding and postoperative complications were compared between the two groups. Results: Of the 198 patients, 86 were males and 112 females. The differences were not statisticly significant in age [52 (44, 63) vs 56 (46, 68) years, P>0.05], history of chronic inflammation [34(35.1%) vs 31(30.7%) cases, P>0.05] and other clinical baseline data between the two groups. Compared with the control group, the fluorescence group had higher efficiency of bile duct identification [18 (16,19) vs 38 (28,55) min,P<0.001], shorter operation time [45 (40,60) vs 80 (65,100) min,P<0.001], less intraoperative bleeding [10 (5,15) vs 60 (20,100) ml,P<0.001], and less postoperative liver function damage [alanine aminotransferase 35.0 (23.4,51.0) vs 98.3 (67.0,134.8)U/L,P<0.001]. In the control group, there was one case of biliary duct injury during operation, one case of postoperative biliary fistula, and one case of postoperative hemorrhage. No similar adverse event was found in fluorescence group. Conclusions: ICG fluorescence imaging can improve the efficiency of LC for patients with acute cholecystitis. It is easy to operate and has a good clinical application value.


Assuntos
Sistema Biliar , Colecistectomia Laparoscópica , Colecistite Aguda , Hepatopatias , Colecistectomia Laparoscópica/métodos , Colecistite Aguda/cirurgia , Corantes , Feminino , Humanos , Verde de Indocianina , Masculino
4.
Phys Chem Chem Phys ; 22(13): 7058-7064, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32196030

RESUMO

Polycrystalline Co2Ti1-xCrxO4 (0 ≤ x ≤ 0.2) inverse spinel ceramics have been synthesized via a sol-gel technique. The dc magnetization measurement in the field-cooled mode shows that negative magnetization could be observed until x reaches 0.2. The exchange constants are calculated using the ferrimagnetic Curie-Weiss fitting and the mean-field theory. This reveals that the strength of the inter sublattice magnetic interaction presents a non-monotonic trend with the increase in Cr content and reaches the minimum at x = 0.1, giving rise to the highest compensation temperature in the x = 0.1 sample. The applicability of the x = 0.1 sample is investigated in light of two prominent magnetic effects: (i) the stable magnetic switching effect indicates the potential applications in magnetic switching and data storage and (ii) the coexistence of normal and inverse magnetocaloric effects suggests a potential application in a constant temperature bath at 54 K.

5.
Environ Technol ; 29(12): 1297-306, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19149351

RESUMO

Batch experiments were conducted to investigate the effects of COD/NO3(-)-N ratio and pH on the accumulation of the denitrification intermediates - nitrite and nitrous oxide - with pyridine as the sole electron donor and carbon source. Significant transient accumulation of nitrite was observed at COD/NO3(-)-N ratios in the range of 2-13 and pH in the range of 6.5-9.5. The optimal pH was 7.5 and the minimum COD/NO3(-)-N ratio was 4 for complete denitrification. The pH had a significant effect on denitrification. At a lower pH of 6.5, the reaction was severely inhibited whereas at a higher pH of 8.5 and 9.5, nitrate was completely reduced, but a high concentration of nitrite remained in the reactors while pyridine was almost completely degraded after one hour, even at the COD/NO3(-)-N ratio of 4. While the specific nitrate reduction rate and nitrite reduction rate in the absence of nitrate remained constant at different COD/NO3(-)-N ratios, they increased with the increase in pH. The nitrite reduction was inhibited in the presence of nitrate because of the faster rate of nitrate reduction over nitrite reduction. Nitrous oxide accumulation was also observed with a COD/NO3(-)-N ratio below 3 in the pH range of 7.5-8.5. At a COD/NO3(-)-N ratio of 4 and pH of 6, the production of nitrous oxide was much higher than that at pH 7 and 8.


Assuntos
Carbono/metabolismo , Nitratos/metabolismo , Nitritos/metabolismo , Piridinas/metabolismo , Purificação da Água/métodos , Elétrons , Concentração de Íons de Hidrogênio , Cinética , Nitratos/química , Nitritos/química , Nitrogênio/química , Nitrogênio/metabolismo , Óxido Nitroso/química , Óxido Nitroso/metabolismo , Oxirredução
6.
Sci Rep ; 8(1): 17093, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30459463

RESUMO

The metal-insulator transition temperature Tc in VO2 is experimentally shown to be almost the same as a magnetic transition temperature Tm characterized by an abrupt decrease in susceptibility, suggesting the evidence of the same underlying origin for both transitions. The measurement of susceptibility shows that it weakly increases on cooling for temperature range of T > Tm, sharply decreases near Tm and then unusually increases on further cooling. A theoretical approach for such unusual observations in susceptibility near Tm or below is performed by modeling electrons from each two adjacent V4+ ions distributed along V-chains as a two-electron system, which indicates that the spin exchange between electrons could cause a level splitting into a singlet (S = 0) level of lower energy and a triplet (S = 1) level of higher energy. The observed abrupt decrease in susceptibility near Tm is explained to be due to that the sample enters the singlet state in which two electrons from adjacent V4+ ions are paired into dimers in spin antiparallel. By considering paramagnetic contribution of unpaired electrons created by the thermal activation from singlet to triplet levels, an expression for susceptibility is proposed to quantitatively explain the unusual temperature-dependent susceptibility observed at low temperatures. Based on the approach to magnetic features, the observed metal-insulator transition is explained to be due to a transition from high-temperature Pauli paramagnetic metallic state of V4+ions to low-temperature dimerized state of strong electronic localization.

7.
Chemosphere ; 43(4-7): 643-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11372848

RESUMO

The contribution of dechlorination reactions to the transformation of dioxins in river sediments was evaluated under a range of geochemical conditions mimicking freshwater, estuarine and marine environments, and interpreted in the light of recent evidence for their accumulation at the air-water interface. The yield of dechlorinated products increased with salinity, but never exceeded 20% of the initial dioxins present. Among the homologue groups in saline conditions, diCDDs were dominant at 32-47 mol% (8-16 nM). The production of 2,3,7,8-TCDD increased with decreasing salinity and in the presence of dissolved organic matter, exhibiting a maximum ratio (2,3,7,8-TCDD:non-2,3,7,8-TCDD) of 0.5. These differences in patterns may be related to the dominant microbial respiratory processes responsible for carbon turnover under the imposed conditions, and are strongly affected by the presence of organic matter. Based on these results, a conceptual dechlorination and carbon turnover model is proposed to help explain the likely reactivity of dioxins in the Passaic River Estuary.


Assuntos
Dioxinas/análise , Poluentes Químicos da Água/análise , Carbono/metabolismo , Compostos Clorados/química , Dioxinas/química , Dioxinas/metabolismo , Monitoramento Ambiental , Sedimentos Geológicos/química , Modelos Teóricos , Compostos Orgânicos/metabolismo , Microbiologia do Solo
8.
Appl Environ Microbiol ; 73(15): 4959-65, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17575004

RESUMO

A soil bacterium capable of metabolizing organophosphorus compounds by reducing the P S group in the molecules was taxonomically identified as Klebsiella sp. strain F51-1-2. The gene involved in the reduction of organophosphorus compounds was cloned from this strain by the shotgun technique, and the deduced protein (named AKR5F1) showed homology to members of the aldo-keto reductase (AKR) superfamily. The intact coding region for AKR5F1 was subcloned into vector pET28a and overexpressed in Escherichia coli BL21(DE3). Recombinant His(6)-tagged AKR5F1 was purified in one step using Ni-nitrilotriacetic acid affinity chromatography. Assays for cofactor specificity indicated that reductive transformation of organophosphorus compounds by the recombinant AKR5F1 specifically required NADH. The kinetic constants of the purified recombinant AKR5F1 toward six thion organophosphorus compounds were determined. For example, the K(m) and k(cat) values of reductive transformation of malathion by the purified recombinant AKR5F1 are 269.5 +/- 47.0 microM and 25.7 +/- 1.7 min(-1), respectively. Furthermore, the reductive transformation of organophosphorus compounds can be largely explained by structural modeling.


Assuntos
Aldeído Redutase , Clonagem Molecular , Escherichia coli/enzimologia , Klebsiella/enzimologia , Oxirredutases do Álcool/química , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Aldeído Redutase/química , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Inibidores da Colinesterase/metabolismo , Escherichia coli/genética , Cinética , Klebsiella/classificação , Klebsiella/genética , Malation/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Compostos Organofosforados/metabolismo , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Especificidade por Substrato
9.
Appl Microbiol Biotechnol ; 63(5): 571-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12908086

RESUMO

Transformation of carbon tetrachloride (CT) by Shewanella oneidensis MR-1 has been proposed to involve the anaerobic respiratory-chain component menaquinone. To investigate this hypothesis a series of menaquinone mutants were constructed. The menF mutant is blocked at the start of the menaquinone biosynthetic pathway. The menB, menA and menG mutants are all blocked towards the end of the pathway, being unable to produce 1,4-dihydroxy-2-naphthoic acid (DHNA), demethyl-menaquinone and menaquinone, respectively. Aerobically grown mutants unable to produce the menaquinone precursor DHNA (menF and menB mutants) showed a distinctly different CT transformation profile than mutants able to produce DHNA but unable to produce menaquinone (menA and menG mutants). While DHNA did not reduce CT in an abiotic assay, the addition of DHNA to the menF and menB mutants restored normal CT transformation activity. We conclude that a derivative of DHNA, that is distinct from menaquinone, is involved in the reduction of CT by aerobically grown S. oneidensis MR-1. When cells were grown anaerobically with trimethylamine-N-oxide as the terminal electron acceptor, all the menaquinone mutants showed wild-type levels of CT reduction. We conclude that S. oneidensis MR-1 produces two different factors capable of dehalogenating CT. The factor produced under anaerobic growth conditions is not a product of the menaquinone biosynthetic pathway.


Assuntos
Tetracloreto de Carbono/metabolismo , Naftóis/química , Naftóis/metabolismo , Shewanella/crescimento & desenvolvimento , Shewanella/metabolismo , Aerobiose , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/fisiologia , Anaerobiose , Biotransformação , Genes Bacterianos , Cinética , Metilaminas/metabolismo , Mutação , Oxirredução , Vitamina K 2/química , Vitamina K 2/metabolismo
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