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1.
J Mol Graph Model ; 131: 108811, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38865932

RESUMO

Silicon-containing arylacetylene resin and its composites have attracted great interest as emerging heat-resistant materials, but their curing mechanisms and products are still elusive. In this work, the influences of the terminal and inner acetylenes on the curing mechanisms of silicon-containing arylacetylene resin with 2,7-diethynylnaphthalene were first identified by density functional theory. Two reaction pathways were proposed and their products include polyenes, anthracene dimers, and benzene trimers. To gain a distinct observation of the cross-linking process, molecular dynamics simulations were used to construct a cross-linking polymerization model. The effects of the temperature on the cured structure were investigated by analyzing the characteristics of the cross-linked network. As expected, higher curing temperature will make the larger proportion of polyene chain and aromatic ring in the terminal alkyne-terminal alkyne route, meanwhile, for the inner alkyne-inner alkyne route, the short chains and a small amount of aromatic rings are major productions. Overall, our cross-linking method may provide an unique guidance for studying the cured structure of other thermosetting resins.


Assuntos
Acetileno , Silício , Silício/química , Acetileno/química , Acetileno/análogos & derivados , Simulação de Dinâmica Molecular , Naftalenos/química , Temperatura , Estrutura Molecular , Reagentes de Ligações Cruzadas/química , Polimerização , Resinas Sintéticas/química
2.
Animals (Basel) ; 14(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38672388

RESUMO

Understanding the spatial variation and formation mechanism of biological diversity is a hot topic in ecological studies. Comparing with α diversity, ß diversity is more accurate in reflecting community dynamics. During the past decades, ß diversity studies usually focused on plants, mammals, and birds. Studies of amphibian ß diversity in montane ecosystems, in particular, tadpoles, are still rare. In this study, Mount Emei, located in southwestern China, was selected as the study area. We explored the tadpole ß diversity in 18 streams, based on a two-year survey (2018-2019). Our results indicated a high total ß diversity in tadpole assemblages, which was determined by both turnover and nestedness processes, and the dominant component was turnover. Both the total ß diversity and turnover component were significantly and positively correlated with geographical, elevational, and environmental distances, but no significant relationship was detected between these and the nestedness component. Moreover, the independent contributions of river width, current velocity, and chlorophyll α were larger than that of geographical and elevational distance. Overall, tadpole ß diversity was determined by both spatial and environmental factors, while the contribution of environmental factors was larger. Future studies can focus on functional and phylogenetic structures, to better understand the tadpole assembly process.

3.
Ecol Evol ; 14(2): e10902, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38371862

RESUMO

Exploring the microhabitat determinants of organisms distribution and functional traits differences can help us better understand the importance of intraspecific variations in ecological niches. Investigations on animals functional niche primarily focused on differences among species and tended to neglect the potential variability within species, despite the fact that the ecological and evolutionary importance of intraspecific variations was widely recognized. In this study, we examined the influence of microhabitat features on the intraspecific variability of the distribution and functional traits of a highest elevational distributed lizard species Phrynocephalus erythrurus. To do so, field work was conducted between July and August, 2020 and August and September, 2021 in Namtso watershed in central Xizang, China. Specifically, 11 transects were sampled for P. erythrurus individuals, which were measured for a set of 10 morphological traits. Moreover, 11 microhabitat variables that potentially affect the distribution of lizards were also measured for each transect. Our results indicated that juveniles, males, and females exhibited different functional traits, allowing them to occupy distinct functional space. The distribution of juveniles, males, and females was determined by different microhabitat variables such as illuminance and air temperature. More importantly, these variables also determined the intraspecific functional traits variability in this lizard species. All of these results supported previous claims that intraspecific traits variation should be incorporated into functional ecological studies, and diverse microhabitat features should be conserved to maintain high intraspecific diversity. Future studies can focus on the food analysis to explore the linkage between functional traits and resources utilization within animal populations.

4.
J Mol Model ; 29(9): 292, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615822

RESUMO

CONTEXT: Reactive molecular dynamics simulations were performed to study the decomposition processes of 1,3,5-trinitro-1,3,5-triazine (RDX) crystal under high temperatures (2100, 2400, 2700, and 3000 K) and detonation pressure (34.5 GPa) and 0 GPa. It is found that the initial decomposition paths of RDX under different temperatures coupled with detonation pressure are similar, which is due to the N-NO2 bond breakage to release NO2. The formation rates of N2 and H2O are significantly affected by temperature, while those of CO2 are less influenced. The C atoms finally formed C clusters. As the temperature rises, the decomposition speeds up, indicating that the high temperature accelerates the decomposition. Applying pressure can reduce the reaction energy barrier and accelerate the decomposition. METHODS: The RDX model was constructed using the Materials Studio 7.0 package. All MD simulations were performed based on the ReaxFF force field in the LAMMPS software package, and the crystals were visualized using the OVITO software package. The time step was 0.1 fs, and the total MD simulation time was 200 ps. DFT calculations were carried out at the B3LYP/6-311G(d,p) level using the Gaussian 09 package.

5.
Mol Omics ; 19(10): 800-809, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37642188

RESUMO

Thyroid cancer (TC) is the most common endocrine malignancy with increasing incidence in recent years. Fine-needle aspiration biopsy (FNAB), as a gold standard for the initial evaluation of thyroid nodules, fails to cover all the cytopathologic conditions resulting in overdiagnosis. There is an urgent need for a better classification of thyroid cancer from benign thyroid nodules (BTNs). Here, data independent acquisition (DIA)-based proteomics and untargeted metabolomics in plasma samples of 10 patients with TC and 15 patients with BTNs were performed. Key proteins and metabolites were identified specific to TC, and an independent cohort was used to validate the potential biomarkers using enzyme-linked immunosorbent assay (ELISA). In total, 1429 proteins and 1172 metabolites were identified. Principal component analysis showed a strong overlap at the proteomic level and a significant discrimination at the metabolomic level between the two groups, indicating a more drastic disturbance in the metabolome of thyroid cancer. Integrated analysis of proteomics and metabolomics shows glycerophospholipid metabolism and arachidonic acid metabolism as key regulatory pathways. Furthermore, a multi-omics biomarker panel was developed consisting of LCAT, GPX3 and leukotriene B4. Based on the AUC value for the discovery set, the classification performance was 0.960. The AUC value of the external validation set was 0.930. Altogether, our results will contribute to the clinical application of potential biomarkers in the diagnosis of thyroid cancer.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/patologia , Proteômica , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Biomarcadores , Metabolômica/métodos
6.
Chin J Integr Med ; 29(10): 895-904, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37542626

RESUMO

OBJECTIVE: To examine the anti-inflammatory effects and potential mechanisms of polypeptide from Moschus (PPM) in lipopolysaccharide (LPS)-induced THP-1 macrophages and BALB/c mice. METHODS: The polypeptide was extracted from Moschus and analyzed by high-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Subsequently, LPS was used to induce inflammation in THP-1 macrophages and BALB/c mice. In LPS-treated or untreated THP-1 macrophages, cell viability was observed by cell counting kit 8 and lactate dehydrogenase release assays; the proinflammatory cytokines and reactive oxygen species (ROS) were measured by enzyme-linked immunosorbent assay and flow cytometry, respectively; and protein and mRNA levels were measured by Western blot and real-time quantitative polymerase chain reaction (qRT-PCR), respectively. In LPS-induced BALB/c mice, the proinflammatory cytokines were measured, and lung histology and cytokines were observed by hematoxylin and eosin (HE) and immunohistochemical (IHC) staining, respectively. RESULTS: The SDS-PAGE results suggested that the molecular weight of purified PPM was in the range of 10-26 kD. In vitro, PPM reduced the production of interleukin 1ß (IL-1ß), IL-18, tumor necrosis factor α (TNF-α), IL-6 and ROS in LPS-induced THP-1 macrophages (P<0.01). Western blot analysis demonstrated that PPM inhibited LPS-induced nuclear factor κB (NF-κB) pathway and thioredoxin interacting protein (TXNIP)/nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NLRP3) inflammasome pathway by reducing protein expression of phospho-NF-κB p65, phospho-inhibitors of NF-κB (Iκ Bs) kinase α/ß (IKKα/ß), TXNIP, NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and pro-caspase-1 (P<0.05 or P<0.01). In addition, qRT-PCR revealed the inhibitory effects of PPM on the mRNA levels of TXNIP, NLRP3, ASC, and caspase-1 (P<0.05 or P<0.01). Furthermore, in LPS-induced BALB/c mice, PPM reduced TNF-α and IL-6 levels in serum (P<0.05 or P<0.01), decreased IL-1ß and IL-18 levels in the lungs (P<0.01) and alleviated pathological injury to the lungs. CONCLUSION: PPM could attenuate LPS-induced inflammation by inhibiting the NF-κB-ROS/NLRP3 pathway, and may be a novel potential candidate drug for treating inflammation and inflammation-related diseases.

7.
J Clin Nurs ; 32(19-20): 7062-7075, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37605069

RESUMO

BACKGROUND: Older people in the nursing home environment are much less mobile and capable of taking care of themselves as they age, and most of them face the plight of loneliness, which seriously affects the quality of life of older people in their later years. AIMS: A systematic review and synthesis of older people's experiences of loneliness in nursing homes. DESIGN: Following ENTREQ, do a systematic evaluation and synthesis of qualitative investigations. METHODS: A search of PubMed, Cochrane Library, Web of Science, Embase, the Chinese biomedical literature service system, the China National Knowledge Infrastructure, the Wanfang Database and the Wipu Database for qualitative studies of older people's experiences of loneliness in nursing homes was conducted with a search time frame of March 2023. Evaluation of the quality of the literature using the Joanna Briggs Institute's Australian Centre for Evidence-Based Health Care Quality Assessment Criteria for Qualitative Research, And the data were synthesised using Thomas and Harden's method of thematic and content analysis. RESULTS: A total of 13 papers were included, and 36 research findings were distilled and integrated into three themes: causes of loneliness; feelings of loneliness; coping with loneliness; and seven sub-themes: aging and loss; environmental transformation; loneliness is a pain; loneliness is a choice; participation; strengthening social ties; and diverting attention. CONCLUSIONS: Older people in nursing homes face varying degrees of loneliness, which is a subjective feeling influenced by the interplay between personal awareness and the external environment, so future care interventions should be developed in a comprehensive manner, taking into account the characteristics of the older people themselves and their external environment. NO PATIENT OR PUBLIC CONTRIBUTION: This study is a meta-synthesis and does not require relevant contributions from patients or the public.


Assuntos
Solidão , Qualidade de Vida , Humanos , Idoso , Austrália , Emoções , Casas de Saúde
8.
Huan Jing Ke Xue ; 44(6): 3585-3599, 2023 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-37309973

RESUMO

Mineral resource bases have dual properties, e.g., mineral resources and environmental pollution. The latter could be classified into natural and anthropogenic pollution based on identifying the spatial distribution characteristics and sources of heavy metals in the soil. The Hongqi vanadium titano-magnetite mineral resources base in Luanping County, Luanhe watershed, was taken as the research object. The geo-accumulation index (Igeo), Nemerow comprehensive pollution index (PN), and potential ecological risk (Ei) were utilized to assess the soil heavy metal pollution characteristics, and redundancy analysis (RDA) and positive determinate matrix factorization (PMF) were employed to identify sources of the soil heavy metals. The results revealed that the mean contents of Cr, Cu, and Ni in the parent material of medium-basic hornblende metamorphic rock and medium-basic gneisses metamorphic rock were 1-2 times that in other parent materials in the concentrated area of mineral resources. However, the mean contents of Pb and As were lower. Fluvial alluvial-proluvial parent materials had the highest mean content of Hg, and the mean content of Cd was higher in the parent materials of medium-basic gneisses metamorphic rocks, acid rhyolite volcanic rocks, and fluvial alluvial-proluvial facies. The Igeodecreased in the following order:Cd>Cu>Pb>Ni>Zn>Cr>Hg>As. PN ranged from 0.61 to 18.99, and the sample proportion of moderate and severe pollution reached 10.00% and 8.08% respectively. Pishowed that the contents of Cu, Cd, Cr, and Ni were relatively higher in the parent material of intermediate-basic hornblende metamorphic rocks and intermediate-basic gneiss metamorphic rocks. Ei decreased in the order of Hg(58.06)>Cd(39.72)>As(10.98)>Cu(6.56) >Pb(5.60)>Ni(5.43)>Cr(2.01)>Zn(1.10). Samples whose RI was lower than 150 accounted for 84.27%, showing that the research area was predominantly at a slight potential ecological risk level. The sources of soil heavy metals were dominated by parent material weathering, followed by the mixed sources of agricultural activities and transportation, the exploitation of mining, and fossil burning, which accounted for 41.44%, 31.83%, 22.01%, and 4.73%, respectively. The risks of heavy metal pollution in the mineral resource base were characterized as multi-source instead of the single source from the mining industry. These research results provide the scientific basis for regional green mining development and eco-environmental protection.

9.
Discov Oncol ; 14(1): 94, 2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37302081

RESUMO

BRAF mutant metastatic colorectal cancer has long been considered a tumor with a poor prognosis and a poor response to chemotherapy. Despite the efficacy of targeted therapy with multi-targeted blockade of the mitogen-activated protein kinase (MAPK) signaling pathway has brought a glimmer of hope to this group of patients, the need to improve treatment efficacy remains unmet, especially for the microsatellite stability/DNA proficient mismatch repair (MSS/pMMR) subtype. BRAF mutant colorectal cancer patients with high microsatellite instability/DNA deficient mismatch repair (MSI-H/dMMR) have high tumor mutation burden and abundant neoantigen, who are deemed as ones that could receive expected efficacy from immunotherapy. Generally, it is believed that MSS/pMMR colorectal cancer is an immunologically "cold" tumor that is insensitive to immunotherapy. However, targeted therapy combined with immune checkpoint blockade therapy seems to bring light to BRAF mutant colorectal cancer patients. In this review, we provide an overview of clinical efficacy and evolving new strategies concerning immune checkpoint blockade therapy for both MSI-H/dMMR and MSS/pMMR BRAF mutant metastatic colorectal cancer and discuss the potential biomarkers in the tumor immune microenvironment for predicting immunotherapeutic response in BRAF mutant colorectal cancer.

10.
Curr Zool ; 69(2): 121-127, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37091999

RESUMO

Reintroduction of captive-bred Chinese giant salamanders is a primary approach for restoring wild populations. Despite previous studies have investigated the habitat preferences of reintroduced Chinese giant salamanders, the intraspecific variation in their habitat selection has been neglected. In the present study, 30 captive-bred Chinese giant salamanders belonging to 3 groups (i.e., 10 males, 10 females, and 10 juveniles) were released into a montane stream to explore whether intraspecific variation in habitat selection occurred in this species using radiotelemetry. Our results indicated that linear home range and daily movement of males were significantly higher than those of females and juveniles. Male sedentariness was significantly lower than that of females and juveniles. No significant differences were detected between females and juveniles in these measures. Importantly, we found that males preferred microhabitats with low water conductivity and deep water depth. Females preferred microhabitats with high water conductivity, low dissolved oxygen and ammonium-nitrogen, and slow current velocity, while juveniles occupied microhabitats with low ammonium-nitrogen. In addition, males and juveniles exhibited higher niche breadth than females. Niche overlap was high between adults and juveniles but low between males and females. Our study revealed the presence of spatial segregation in reintroduced Chinese giant salamanders. Males, females, and juveniles exhibited variation in microhabitat selection. These results provide important information for use when planning strategies for conservation of Chinese giant salamanders.

11.
Front Zool ; 20(1): 7, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36740695

RESUMO

BACKGROUND: Functional diversity is important to maintain ecosystem functioning. Species with different ecomorphological traits may display distinct functional roles in ecosystems. Accordingly, functionally extreme species are more important as they can exhibit specific strategies. However, little is known about the distribution patterns of functionally extreme species at a local scale and whether the prior extinction of extreme species can cause significant effects on functional diversity. In addition, no empirical studies have been conducted on the microhabitat determinants of extreme species to maintain the functional diversity. RESULTS: This study collected 1470 tadpoles belonging to 6 families and 20 anuran species. These species were subsequently divided into 65 functional entities based on their developmental stages to incorporate intraspecific traits variability. As a result, we detected seven extreme functional entities, accounting for 10.7% of the total number of entities. Moreover, the prior extinction of extreme entities can lead to a significant decrease in functional diversity compared with the random extinction of entities. Microhabitat variables such as conductivity, water depth, and current velocity determined the distribution of extreme entities. CONCLUSION: Although the functionally extreme entities only represented a small proportion of the total number of tadpoles, they played irreplaceable roles in maintaining functional diversity. Their extinction may induce high functional vulnerability in tadpole communities. Therefore, anuran species with extreme tadpole traits need to be projected for amphibian conservation.

12.
Molecules ; 29(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38202639

RESUMO

ReaxFF-lg molecular dynamics method was employed to simulate the decomposition processes of IHEM-1 nanoparticles at high temperatures. The findings indicate that the initial decomposition paths of the nanoparticles with different sizes at varying temperatures are similar, where the bimolecular polymerization reaction occurred first. Particle size has little effect on the initial decomposition pathway, whereas there are differences in the numbers of the species during the decomposition and their evolution trends. The formation of the hydroxyl radicals is the dominant decomposition mechanism with the highest reaction frequency. The degradation rate of the IHEM-1 molecules gradually increases with the increasing temperature. The IHEM-1 nanoparticles with smaller sizes exhibit greater decomposition rate constants. The activation energies for the decomposition are lower than the reported experimental values of bulk explosives, which suggests a higher sensitivity.

13.
Front Pharmacol ; 13: 1023713, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36479195

RESUMO

Type 2 diabetes mellitus (T2DM) is a metabolic disease with persistent hyperglycemia primarily caused by insulin resistance (IR). The number of diabetic patients globally has been rising over the past decades. Although significant progress has been made in treating diabetes mellitus (DM), existing clinical drugs for diabetes can no longer fully meet patients when they face complex and huge clinical treatment needs. As a traditional and effective medical system, traditional Chinese medicine (TCM) has a unique understanding of diabetes treatment and has developed many classic and practical prescriptions targeting DM. With modern medicine and pharmacy advancements, researchers have discovered that various bioactive metabolites isolated from TCM show therapeutic on DM. Compared with existing clinical drugs, these bioactive metabolites demonstrate promising prospects for treating DM due to their excellent biocompatibility and fewer adverse reactions. Accordingly, these valuable metabolites have attracted the interest of researchers worldwide. Despite the abundance of research works and specialized-topic reviews published over the past years, there is a lack of updated and systematic reviews concerning this fast-growing field. Therefore, in this review, we summarized the bioactive metabolites derived from TCM with the potential treatment of T2DM by searching several authoritative databases such as PubMed, Web of Science, Wiley Online Library, and Springer Link. For the convenience of readers, the content is divided into four parts according to the structural characteristics of these valuable compounds (flavonoids, terpenoids, alkaloids, and others). Meanwhile, the detailed mechanism and future directions of these promising compounds curing DM are also summarized in the related sections. We hope this review inspires increasingly valuable and significant research focusing on potential bioactive metabolites from TCM to treat DM in the future.

14.
Front Microbiol ; 13: 1062604, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532427

RESUMO

Microorganisms play as fundamental contributors to maintain hosts' fitness, which can be shaped by external environment. Moreover, symbiotic microbiome also varied within species (e.g., between sexes and developmental stages). However, we still need more studies to quantify whether the intraspecific variation patterns of symbiotic microbes can be modified with the change of environment. The Chinese giant salamander (CGS; Andrias davidianus) is a Critically Endangered species. Despite quantitative captive bred individuals were released to rebuild wild populations, the effectiveness is limited. More importantly, no studies have revealed the adaptation of released CGSs to the complex field conditions. In the present study, we explored whether reintroduction can reshape the intraspecific variations of symbiotic microbiota in captive bred CGSs using high-throughput amplicon sequencing of the16S rRNA gene. We found no significant difference of symbiotic microbiome in captive bred males and females, but released males and females differed significantly in skin microbiome. Juveniles had higher diversity of microbial symbiont than adults in hatchery, but lower diversity in field. Moreover, dominant bacterial taxa differed between juveniles and adults in both hatchery and field. Importantly, this symbiotic microbiome variations within species can be modified (alpha and beta diversity, and community composition) when captive bred individuals were released to the field. Overall, we observed a lower alpha diversity and higher relative abundance of Chryseobacterium, Plesiomonas, and Acinetobacter in the bacterial community of captive bred individuals. Instead, higher alpha diversity of symbiotic microbiota and higher relative abundance of S24-7 and Lactobacillus was detected in released individuals. These modifications may associate with the change of living environment, as well as the specific behavior within CGSs (e.g., movement patterns and foraging activities). Future studies can incorporate other approaches (e.g., blood physiology) to better evaluate the growth and health of reintroduced CGSs.

15.
Animals (Basel) ; 12(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35804571

RESUMO

Phylogenetic structure is a key facet of biodiversity, reflecting the evolutionary history of species, and thus can be used to understand various ecological patterns. Although amphibian phylogenetic structures have been tested across space and time separately, simultaneous quantifications are still needed. In the present study, amphibians in streams of Tianping mountain, China, were selected as the model to investigate their elevational spatial and seasonal temporal patterns of phylogenetic diversity. Specifically, 13 streams located in lowland and highland sites were sampled for amphibians and measured for microhabitat variables in April, June, August, and October 2017, separately. Four phylogenetic structural indices, including Faith's PD, standardized effect size (SES) of Faith's PD, mean pairwise phylogenetic distance index (MPD), and SES.MPD, were calculated. Our results revealed that amphibian phylogenetic patterns were not significantly different between lowland and highland sites, but differed significantly between four seasons, associated with distinct community assembly rules (phylogenetically overdispersed vs. phylogenetically clustered). Importantly, these patterns were strongly determined by microhabitat variables such as rock cover, water temperature, and water depth. Our results provide fundamental knowledge to better protect amphibian diversity. Both elevational and seasonal variations are important to understanding the general patterns of amphibian community assembly rules.

16.
Entropy (Basel) ; 24(4)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35455232

RESUMO

Entropy generation analysis of the flow boiling in microgravity field is conducted in this paper. A new entropy generation model based on the flow pattern and the phase change process is developed in this study. The velocity ranges from 1 m/s to 4 m/s, and the heat flux ranges from 10,000 W/m2 to 50,000 W/m2, so as to investigate their influence on irreversibility during flow boiling in the tunnel. A phase-change model verified by the Stefan problem is employed in this paper to simulate the phase-change process in boiling. The numerical simulations are carried out on ANSYS-FLUENT. The entropy generation produced by the heat transfer, viscous dissipation, turbulent dissipation, and phase change are observed at different working conditions. Moreover, the Be number and a new evaluation number, EP, are introduced in this paper to investigate the performance of the boiling phenomenon. The following conclusions are obtained: (1) a high local entropy generation will be obtained when only heat conduction in vapor occurs near the hot wall, whereas a low local entropy generation will be obtained when heat conduction in water or evaporation occurs near the hot wall; (2) the entropy generation and the Be number are positively correlated with the heat flux, which indicates that the heat transfer entropy generation becomes the major contributor of the total entropy generation with the increase of the heat flux; (3) the transition of the boiling status shows different trends at different velocities, which affects the irreversibility in the tunnel; (4) the critical heat flux (CHF) is the optimal choice under the comprehensive consideration of the first law and the second law of the thermodynamics.

17.
ACS Omega ; 7(13): 11343-11352, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35415355

RESUMO

Moracins, a kind of 2-phenyl-benzofuran compound from Moraceae, serve as phytoalexins with antimicrobial, anti-inflammatory, antitumor, and antidiabetes activities and respond to biotic and abiotic stresses, while their biosynthetic pathway and regulatory mechanism remain unclear. Here, we report a de novo transcriptome sequencing for different tissues of seedlings, as well as leaves under different stresses, in M. alba L. A total of 88 282 unigenes were assembled with an average length of 937 bp, and 82.2% of them were annotated. On the basis of the differential expression analysis and enzymatic activity assays in vitro, moracins were traced to the phenylpropanoid pathway, and a putative biosynthetic pathway of moracins was proposed. Unigenes coding key enzymes in the pathway were identified and their expression levels were verified by real-time quantitative reverse transcription PCR (qRT-PCR). Particularly, a p-coumaroyl CoA 2'-hydroxylase was presumed to be involved in the biosynthesis of stilbenes and deoxychalcones in mulberry. Additionally, the transcription factors that might participate in the regulation of moracin biosynthesis were obtained by coexpression analysis. These results shed light on the putative biosynthetic pathway of moracins, providing a basis for further investigation in functional characterization and transcriptional regulation of moracin biosynthesis in mulberry.

18.
BMC Gastroenterol ; 22(1): 30, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062873

RESUMO

BACKGROUND: The prognosis difference based on the depth of tumor muscularis propria invasion in gastric cancer (GC) was still debated, and therapy strategy for stage IB GC patient required further investigation. METHODS: A total of 380 patients with pT2 GC after radical surgery were retrospectively analyzed, including 185 in superficial muscularis propria (sMP) group and 195 in deep muscularis propria (dMP) group. RESULTS: The overall survival (OS) was significantly better for patients in sMP group than for patients in dMP group (P = 0.007). In multivariate analysis, depth of tumor invasion, pN stage, age, primary location, positive expression of p53, elevated maximal LDH, elevated initial CA19-9 and AFP level were independent prognostic factors for OS. The sMP group had a significantly better OS than dMP group (P = 0.014) in pN0 stage. After further stratification, the survival outcomes were not significantly different between deep muscularis propria tumor invasion without lymph node metastasis (dMPN0) group (stage IB) and superficial muscularis propria tumor invasion with stage 1-2 lymph node metastasis (sMPN1-2) group (stage II) (P = 0.100). Patients with adjuvant chemotherapy had a statistically better survival than those without in dMPN0 group (P = 0.045) and dMPN0 patients with adjuvant chemotherapy had better OS than sMPN1-2 patients (P = 0.015). In addition, greater postoperative survival could be observed in sMPN0 patients than dMPN0 patients in p53-positive group (P = 0.002), and similar OS could be seen between dMPN0 patients with p53-positive and T2N1-2 patients (P = 0.872). CONCLUSION: As a unique subclassification of stage IB GC, appropriate adjuvant chemotherapy should be considered for patients with dMPN0 stage. In addition, positive expression of p53, elevated LDH could be potential factors in identifying the different prognoses for stage IB GC patients.


Assuntos
Neoplasias Gástricas , Humanos , Metástase Linfática , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
19.
Front Genet ; 12: 646818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512711

RESUMO

BACKGROUND: Stomach adenocarcinoma (STAD) is the most common histological type of stomach cancer, which causes a considerable number of deaths worldwide. This study aimed to identify its potential biomarkers with the notion of revealing the underlying molecular mechanisms. METHODS: Gene expression profile microarray data were downloaded from the Gene Expression Omnibus (GEO) database. The "limma" R package was used to screen the differentially expressed genes (DEGs) between STAD and matched normal tissues. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) was used for function enrichment analyses of DEGs. The STAD dataset from The Cancer Genome Atlas (TCGA) database was used to identify a prognostic gene signature, which was verified in another STAD dataset from the GEO database. CIBERSORT algorithm was used to characterize the 22 human immune cell compositions. The expression of LRFN4 and CTHRC1 in tissues was determined by quantitative real-time PCR from the patients recruited to the present study. RESULTS: Three public datasets including 90 STAD patients and 43 healthy controls were analyzed, from which 44 genes were differentially expressed in all three datasets. These genes were implicated in biological processes including cell adhesion, wound healing, and extracellular matrix organization. Five out of 44 genes showed significant survival differences. Among them, CTHRC1 and LRFN4 were selected for construction of prognostic signature by univariate Cox regression and stepwise multivariate Cox regression in the TCGA-STAD dataset. The fidelity of the signature was evaluated in another independent dataset and showed a good classification effect. The infiltration levels of multiple immune cells between high-risk and low-risk groups had significant differences, as well as two immune checkpoints. TIM-3 and PD-L2 were highly correlated with the risk score. Multiple signaling pathways differed between the two groups of patients. At the same time, the expression level of LRFN4 and CTHRC1 in tissues analyzed by quantitative real-time PCR were consistent with the in silico findings. CONCLUSION: The present study constructed the prognostic signature by expression of CTHRC1 and LRFN4 for the first time via comprehensive bioinformatics analysis, which provided the potential therapeutic targets of STAD for clinical treatment.

20.
Int J Clin Pract ; 75(11): e14663, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34387916

RESUMO

OBJECTIVES: To investigate the clinical and pathological features of multiple primary malignant neoplasms (MPMNs) cases. METHODS: The clinical data of 24 105 tumour patients admitted to Jiangsu Cancer Hospital in 2018 were retrospectively reviewed, and 270 patients with MPMNs were selected as the research subjects. Among them, 101 cases of synchronous carcinoma (SC) and 92 cases of metachronous carcinoma (MC) were divided into groups for statistical analysis. Univariate and multivariate cox regression analyses were conducted using SPSS 22.0 software. RESULTS: Among 24 105 cases, there was a male-to-female ratio of 1.45:1. Compared with MC cases, SC patients have a higher proportion of male cases. Primary neoplasms in gastric cancer, head and neck cancer, oesophageal cancer and colon cancer occupied most cases in male MPMNs, while primary breast cancer ranked first in female MPMNs. In addition, the leading secondary neoplasms were duodenal carcinoma, lung cancer and male MPMNs and lung cancer in female MPMNs. As for SC MPMNs, primary neoplasms were occupied by lung cancer, gastric cancer and oesophageal cancer, while the secondary neoplasms were mostly consisted of oesophageal cancer and lung cancer. Finally, the MC MPMNs were mostly consisted of breast cancer and gastric cancer as primary neoplasms, while lung cancer and oesophageal cancer as secondary neoplasms. CONCLUSIONS: Screening for primary cancer should be strengthened over the age of 50 years for male patients with gastric cancer or female patients with breast cancer to reduce or monitor the occurrence of MPMNs.


Assuntos
Neoplasias da Mama , Neoplasias Esofágicas , Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Neoplasias da Mama/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/epidemiologia , Estudos Retrospectivos
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