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1.
Bioresour Technol ; : 122746, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31956057

RESUMO

In order to maximize the substrate conversion, co-production of hydrogen and methane from two-stage anaerobic digestion has attracted wide attention. In two-stage fermentation process, the cohesive strategy is considered as a key indicator for bio-hythane yield. In this work, corncob powder was utilized as raw material. The pH of fermentative broth, bio-hythane yield, gas production rate and energy conversion efficiency were taken as indexes. Under the directional control of bio-chemical reaction process, the effects of diverse coupling time nodes on the fermentation process and the bio-hythane co-production potential were investigated. The results showed that when the coupling time node was 48 h, hydrogen production potential and methane production potential were 22.29 mL/g TS and 141.14 mL/g TS, respectively. The hydrogen content in the bio-hythane was 13.64% which satisfied the hydrogen concentration requirement, and the energy conversion efficiency was 27.6%.

3.
Cancer Imaging ; 20(1): 4, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924270

RESUMO

OBJECTIVE: To investigate the 18F-FDG PET/CT imaging manifestations for anaplastic large cell lymphoma (ALCL), a rare subtype of T/NK cell lymphoma. METHODS: Fifty patients with ALCL, including 32 anaplastic lymphoma kinase (ALK)-positive patients and 18 ALK-negative patients, were enrolled. The positive detection, maximal standardized uptake value (SUVmax), and distribution of nodal and extranodal involvement were recorded and analysed. Fifty patients with diffuse large B cell lymphoma (DLBCL) were collected as a control group. RESULTS: ALCL lesions were demonstrated to be 18F-FDG-avid tumours with a mean SUVmax of 19.4 ± 12.6. Most (76%) ALCL patients presented with stage III-IV disease, and nodal and extranodal involvement occurred in 74.0 and 72.0% of the patients, respectively. ALCL and DLBCL showed many similarities in tumour stage, 18F-FDG uptake and tumour involvement (P > 0.05), although the preferred extranodal organs of involvement (bone and the gastrointestinal tract, respectively) were different (P < 0.05). Compared to ALK-negative lesions, a higher uptake of 18F-FDG was found in the ALK-positive lesions (SUVmax: 22.1 ± 14.3 vs. 15.1 ± 6.6, t = 2.354, P = 0.023). ALK-positive ALCL was more likely to involve the lymph nodes than ALK-negative ALCL (84.3% vs. 55.5%, χ2 = 4.973, P = 0.043), while ALK-negative ALCL was more prone to involve the extranodal organs compared to ALK-positive ALCL (88.9% vs. 62.5%, χ2 = 3.979, P = 0.046). CONCLUSION: The present study demonstrated that ALCL is a systemic 18F-FDG-avid lymphoma with many imaging manifestations similar to DLBCL on PET/CT. The present study also showed that ALK expression actually influenced tumour 18F-FDG uptake and lesion distribution. These findings may be useful to improve the understanding of the biological characteristics of ALCL.

4.
Plant Cell Physiol ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904850

RESUMO

Autopolyploids often show growth advantages over their diploid progenitors because of their increased photosynthetic activity; however, the underlying molecular basis of such mechanism remains elusive. Here, we aimed to characterize autotetraploid pak choi (Brassica rapa ssp. chinensis) at the physiological, cellular, and molecular levels. Autotetraploid pak choi has thicker leaves than its diploid counterparts, with relatively larger intercellular spaces and cell size and greater grana thylakoid height. Photosynthetic data showed that the relative electron transport rate (rETR) was markedly higher in autotetraploid than in diploid pak choi. Transcriptomic data revealed that the expressions of genes involved in 'photosynthesis' biological process and 'thylakoids' cellular component were mainly regulated in autotetraploids. Overall, our findings suggested that the increased rETR in the thylakoids contributed to the increased photosynthetic capacity of autotetraploid leaves. Furthermore, we found that the enhanced rETR is associated with increased BrPetC expression, which is likely altered by histone modification. The ectopic expression of BrPetC in Arabidopsis thaliana led to increased rETR and biomass, which were decreased in BrPetC-silenced pak choi. Autotetraploid pak choi also show altered hormone levels, which was likely responsible for the increased drought resistance and impaired powdery mildew resistance of this lineage. Our findings further our understanding on how autotetraploidy provides growth advantages to plants.

5.
Inorg Chem ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31909612

RESUMO

A rotorlike supramolecular crystal, {[K(18-crown-6)]PbI3}∞, is composed of a linear [PbI3]∞ chain acting as a stator and [K(18-crown-6)]+ cations fastened to the [PbI3]∞ chain and K-I bond like rotators and axes, respectively. A reversible breaking-symmetry phase transition occurs at ∼305 K. Variable-temperature 1H NMR spectra and dielectrics were used for the dynamic analysis of [K(18-crown-6)]+ cations in the crystal.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31909965

RESUMO

M2B5O9X is a prominent family with excellent nonlinear optical (NLO) responses, just as the Pb2B5O9I crystal with a large second harmonic generation (SHG) of 13.5 times that of KH2PO4. However, most of these compounds are limited to ultraviolet and visible regions because of their long absorption edge (small band gap). Here, we report two members of this family, which change the situation. Using a high-temperature solution method, we obtain Ca2B5O9Cl and Sr2B5O9Cl crystals, which exhibit a deep-ultraviolet (DUV) absorption edge of 170 nm (band gap ≈ 7.29 eV). It is an important breakthrough in the DUV transparency of the M2B5O9X family. Furthermore, Ca2B5O9Cl crystals display a phase-matching SHG response under a 1064 nm laser, which is further confirmed by the balance between the suitable birefringence and the small dispersion of refractive indexes in the wavelength range of 1064-532 nm. Therefore, they are promising DUV transparency windows and NLO candidates.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31802535

RESUMO

BACKGROUND AND AIM: Endoscopic stenting for unresectable malignant hilar biliary strictures (MHBS) remains challenging. Post-endoscopic retrograde cholangiopancreatography (ERCP) cholangitis (PEC) can be the most common and fatal adverse event. In the present study, we aimed to systematically evaluate the incidence, severity, risk factors and consequences of PEC after endoscopic procedures for advanced MHBS. METHODS: Of 924 patients, we identified 502 patients with MHBS (Bismuth type II to IV) who underwent endoscopic stenting as the primary therapy at two centers over 16 years. PEC and its severity were verified according to the current Tokyo guidelines. RESULTS: A total of 108 patients (21.5%) experienced acute PEC. Mild, moderate and severe cholangitis was encountered in 51 (10.1%), 42 (8.4%) and 15 (3.0%) patients, respectively. Multivariate analyses showed that metal stenting (verse plastic stenting) (OR 0.328, 95% CI 0.200-0.535, p<0.001) and Bismuth classification (IV vs. III/II) (OR 2.499, 95% CI 1.150-5.430) were independent predictors for PEC and the moderate/severe type. Patients with PEC had significantly lower clinical success rates (86.3% vs 41.7%, p<0.001), a higher rate of early death (6.5% vs. 0.5%, p<0.001), a shorter median stent patency (4.9 vs. 6.4 months, p<0.001), and shorter overall survival (2.6 vs. 5.2 months, p<0.001) compared to the noncholangitis group. CONCLUSIONS: After endoscopic stenting for advanced MHBS, cholangitis may occur in as many as 21.5% of patients, which may be associated with a poor prognosis. The risk is high in patients with Bismuth type IV and may be reduced by using metal stents.

9.
World J Gastrointest Endosc ; 11(12): 548-560, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31839874

RESUMO

Endoscopic treatment of gastrointestinal diseases has developed rapidly in recent years, due to its minimally invasive nature. One of the main contributing factors for this progress is the improvement of endoscopic instruments, which are essential for facilitating safe and effective endoscopic interventions. However, the slow learning curve required in the implementation of many advanced endoscopic procedures using standard devices is associated with a high risk of complications. Other routine procedures may also be complicated by unexpected difficulties. Based on the ferromagnetic properties of many objects, both internal and external magnetic devices have been developed and applied for multiple endoscopic interventions. The applications of magnets, mainly including compression, anchoring and traction, facilitate many difficult procedures and make it feasible to operate procedures that were previously impossible. Other novel endoscopic applications, such as magnetic nanoparticles, are also under development. In this article, we reviewed published studies of endoscopic applications of magnets for the treatment of gastrointestinal diseases such as precancerous lesions and cancer, obstruction, stricture, congenital and acquired malformations, motility disorders, and ingestion of foreign bodies. Since several endoscopic applications of magnets may also be relevant to surgery, we included them in this review.

10.
J Clin Ultrasound ; 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846085

RESUMO

PURPOSE: The aim of this study was to determine the elastic modulus values of normal liver tissue in school-age children by shear wave elastography (SWE) and to study the factors that influence these stiffness measurements. METHODS: Six hundred and four school-age children (295 girls and 309 boys) who were recruited at a hospital and had normal results of specific laboratory tests and imaging studies underwent SWE examinations. The elastic modulus values were obtained in segment V and VI for each subject and comparisons were made between age groups. RESULTS: The mean elastic modulus values for school-age children were 6.3 ± 1.1 kPa for segment V and 6.2 ± 1.1 kPa for segment VI. A positive linear trend in liver stiffness was found for the 6 to 9-year-old age group in segments V and VI (R2 = 0.076 vs R2 = 0.085, respectively, P < .05). No statistically significant difference in liver stiffness was found between genders and between segment groups (P > .05). CONCLUSION: SWE is a feasible method to measure liver stiffness in the school-age population. We established a normal range of liver elastic modulus values in school-age children, which will provide a basis for evaluating the changes in liver stiffness caused by various diseases.

11.
Dalton Trans ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31848553

RESUMO

Two transition metal-antimony oxo-cluster based compounds, H5{MCd(H2O)6[M(H2O)3Co3SbVSbIII6(µ3-O)8(l-tta)6]}·7H2O (1) (M = Cd0.5 + Co0.5) and H3K5(H2O)11{Cd(H2O)4[Cd(H2O)Fe4Cd2Sb6(µ4-O)5(µ3-O)3(l-tta)6][Cd(H2O)2Fe4Cd2Sb6(µ4-O)4(µ3-O)4(l-tta)6][Cd(H2O)2Fe4Cd2Sb6(µ4-O)4(µ3-O)4(l-tta)6Cd(H2O)5]}·17H2O (2) (L-H4tta = l-tartaric acid) were hydrothermally synthesized and characterized. Compound 1 features a [MCo3SbVSbIII6(µ3-O)8(l-tta)6(H2O)3]9- cluster, while compound 2 contains three types of clusters, namely, [Cd(H2O)Fe4Cd2Sb6(µ4-O)5(µ3-O)3(l-tta)6]4-, [Cd(H2O)2Fe4Cd2Sb6(µ4-O)4(µ3-O)4(l-tta)6]4- and [Cd(H2O)2Fe4Cd2Sb6(µ4-O)4(µ3-O)4(l-tta)6Cd(H2O)5]2-. All the clusters are of sandwich-type with {Sb3(µ3-O)(l-tta)} scaffolds on the top and bottom. The Cd (and M in 1) ions interconnect the clusters into layered structures in both compounds. To the best of our knowledge, this is the first report of transition metal-antimony oxo-clusters that simultaneously contain the first-row and second-raw transition metal ions, and compound 1 represents the first example of such type of clusters that contain Sb(v). The two compounds exhibit proton conductivity with the values of 2.43 × 10-3 and 2.95 × 10-3 S cm-1 at 85 °C under 98% relative humidity, respectively.

12.
Gastrointest Endosc ; 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31881205

RESUMO

BACKGROUND AND AIMS: The endoscopic management of malignant hilar biliary obstruction (MHBO) remains extremely challenging without a universal consensus. We compared, for the first time, 4 major modalities aiming to determine the optimal strategy. METHODS: We reviewed 1239 patients with advanced MHBO who underwent endoscopic stent placement as the primary treatment in 4 tertiary centers. Among them, 633 eligible patients were identified and classified into 4 groups: bilateral metal stent placement (BMS), unilateral metal stent placement (UMS), bilateral plastic stent placement (BPS), and unilateral plastic stent placement (UPS). The outcomes were compared before and after propensity score matching (PSM). RESULTS: After PSM, 87, 97, 91, and 81 patients in the BMS, UMS, BPS, and UPS groups, respectively, were matched. The clinical success rates were 98.9%, 83.5%, 71.4%, and 65.4% in the BMS, UMS, BPS, and UPS groups (p<0.001), respectively. The postprocedural cholangitis rates were 8.0%, 17.5%, 26.4%, and 29.6% (p=0.002), respectively. The median symptom-free stent patency was 9.6, 6.8, 4.6, and 4.2 months (p<0.001), respectively. The mean total interventions required was 1.2±0.5, 1.7±0.8, 2.0±1.4, and 1.9±1.3 (p<0.001), respectively. The median (95% confidence interval) overall survival (OS) was 7.1 (6.0-8.2), 4.4 (3.8-4.9), 4.1 (2.9-5.2), and 2.7 (1.8-3.7) months (p=0.001), respectively. Compared with plastic stent placement, metal stent placement achieved higher success in all outcome parameters (p≤0.001). Bilateral stent placement was superior to unilateral stent placement in terms of clinical success (p=0.024), stent patency (p=0.018), and OS (p=0.040). CONCLUSIONS: If technically possible, dual metal stent placement could be a preferred palliation for inoperable MHBO, and unilateral metal stent placement be the second option.

13.
Curr Microbiol ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712900

RESUMO

A Gram-stain-negative, rod-shaped bacterial strain JS15-10A1T was isolated from oil production water. Its optimum growth was observed at 37 °C, pH 7.0, and 3% (w/v) NaCl. The 16S rRNA gene sequence of strain JS15-10A1T showed the highest similarities with Pseudomonas parafulva CB-1T (97.6%) and P. fulva IAM 1529T (97.5%). In addition, phylogenetic analyses based on multilocus sequence analyses with concatenating 16S rRNA, gyrB, rpoD, and rpoB genes indicated that strain JS15-10A1T was a member of genus Pseudomonas but discriminated from other species. Furthermore, whole-genome analyses revealed that average nucleotide identities and in silico DNA-DNA hybridization values of strain JS15-10A1T against its closest relatives were all below 76.7% and 21.1%, respectively. The major cellular fatty acids of strain JS15-10A1T were summed feature 8 (C18:1ω7c/C18:1ω6c), C16:0, C12:0, C17:0 cyclo, summed feature 3 (C16:1ω7c/C16:1ω6c), C12:0 3-OH, C10:0 3-OH, and C19:0 cyclo ω8c. The predominant quinone was ubiquinone Q-9. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown amino-lipid, and two unidentified lipids. The genome DNA G + C content was 60.0 mol%. On the basis of phylogenetic, phenotypic, physiological, and chemotaxonomic analyses, it can be concluded that strain JS15-10A1T represents a novel species in genus Pseudomonas, for which the name Pseudomonas jilinensis sp. nov. is proposed. The type strain is JS15-10A1T (= CGMCC 1.16072T = LMG 30036T).

14.
Neurosci Bull ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713716

RESUMO

Preterm infants are vulnerable to brain injuries, and have a greater chance of experiencing neurodevelopmental disorders throughout development. Early screening for motor and cognitive functions is critical to assessing the developmental trajectory in preterm infants, especially those who may have motor or cognitive deficits. The brain imaging technology functional near-infrared spectroscopy (fNIRS) is a portable and low-cost method of assessing cerebral hemodynamics, making it suitable for large-scale use even in remote and underdeveloped areas. In this article, we review peer-reviewed, scientific fNIRS studies of motor performance, speech perception, and facial recognition in preterm infants. fNIRS provides a link between hemodynamic activity and the development of brain functions in preterm infants. Research using fNIRS has shown different patterns of hemoglobin change during some behavioral tasks in early infancy. fNIRS helps to promote our understanding of the developmental mechanisms of brain function in preterm infants when performing motor or cognitive tasks in a less-restricted environment.

15.
Sci Rep ; 9(1): 17396, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31758023

RESUMO

Propionate is one of the most important intermediates of anaerobic fermentation. Its oxidation performed by syntrophic propionate-oxidizing bacteria coupled with hydrogenotrophic methanogens is considered to be a rate-limiting step for methane production. However, the current understanding of SPOB is limited due to the difficulty of pure culture isolation. In the present study, two anaerobic chemostats fed with propionate as the sole carbon source were operated at different dilution rates (0.05 d-1 and 0.15 d-1). The propionate- and acetate-oxidizing bacteria in the two methanogenic chemostats were investigated combining DNA-stable isotope probing (DNA-SIP) and 16S rRNA gene high-throughput sequencing. The results of DNA-SIP with 13C-propionate/acetate suggested that, Smithella, Syntrophobacter, Cryptanaerobacter, and unclassified Rhodospirillaceae may be putative propionate-oxidizing bacteria; unclassified Spirochaetaceae, unclassified Synergistaceae, unclassified Elusimicrobia, Mesotoga, and Gracilibacter may contribute to acetate oxidation; unclassified Syntrophaceae and Syntrophomonas may be butyrate oxidizers. By DNA-SIP, unclassified OTUs with 16S rRNA gene abundance higher than 62% of total Bacteria in the PL chemostat and 38% in the PH chemostat were revealed to be related to the degradation of propionate. These results suggest that a variety of uncultured bacteria contribute to propionate degradation during anaerobic digestion. The functions and metabolic characteristics of these bacteria require further investigation.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31683465

RESUMO

PURPOSE: The aim of this study was to evaluate the diagnostic value of conventional sonography and ultrasound elastography for thyroid nodules of each Bethesda category and to analyze their potential role in the corresponding management decision. METHODS: This retrospective study included 557 thyroid nodules diagnosed by conventional ultrasound (US) and real-time ultrasound elastography (RTE) before fine-needle aspiration (FNA) from 458 patients. The US, RTE, and cytological results were collected and analyzed according to different Bethesda categories. Differences in the distribution of sonographic features between groups were evaluated by the Chi-square test or Fisher exact test. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of conventional US and RTE for the diagnosis of malignant nodules in each category were then calculated and analyzed. RESULTS: The diagnostic accuracy of the comprehensive US diagnosis in all categories stayed at a relatively high level from 78.4% to 88.6%, and good specificities ranging from 77.3% to 100% were revealed in all Bethesda categories. As to RTE, the diagnostic accuracies in categories I-IV stayed at a relatively low level ranging from 44.6% to 65.6% except for better performance in categories V and VI (85.2%, 89.1%). Besides, the accuracies of comprehensive US (85.2%, 88.6%) and RTE (85.2%, 89.1%) is relatively low compared to the corresponding cytological diagnoses in categories V and VI. CONCLUSIONS: Conventional US is complementary to FNA for providing additional hints especially in categories I-IV for further clinical managements, while RTE failed to provide useful diagnostic information in general.

19.
Open Biol ; 9(10): 190137, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31662097

RESUMO

One of the major topics in magnetobiology is the biological effects of strong static magnetic field (SMF) on living organisms. However, there has been a paucity of the comprehensive study of the long-term effects of strong SMF on an animal's development. Here, we explored this question with zebrafish, an excellent model organism for developmental study. In our research, zebrafish eggs, just after fertilization, were exposed to a 9.0 T SMF for 24 h, the critical period of post-fertilization development from cleavage to segmentation. The effects of strong SMF exposure on the following developmental progress of zebrafish were studied until 6 days post-fertilization (dpf). Results showed that 9.0 T SMF exposure did not influence the survival or the general developmental scenario of zebrafish embryos. However, it slowed down the developmental pace of the whole animal, and the late developers would catch up with their control peers after the SMF was removed. We proposed a mechanical model and deduced that the development delaying effect was caused by the interference of SMF in microtubule and spindle positioning during mitosis, especially in early cleavages. Our research data provide insights into how strong SMF influences the developing organisms through basic physical interactions with intracellular macromolecules.

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