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1.
J Environ Manage ; 317: 115487, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35751282

RESUMO

Rural landscapes offer a variety of cultural ecosystem services (CESs). However, the relationship between rural landscape characteristics and different CESs is still poorly understood. Therefore, this study explored the rural areas of Huzhou city, China, as a case study to assess the main rural landscape characteristics of different CESs based on public preferences. First, 148 scenic spots were classified into four CESs (physical, experiential, intellectual and inspirational), and the public preferences for each scenic spot were determined by combining tourists' scores obtained from social media and government assessment scores. Then, the landscape characteristic indicators were constructed from the natural, infrastructural and sensory perspectives by combining geographic and social media data. Finally, the random forest model was used to evaluate the public preferences for rural landscape characteristics overall and for different CESs. The word frequency analysis showed that, in addition to the nature landscape, infrastructure and service had a strong influence on public preferences. The relationship with rural landscape characteristics varied across different CESs. For physical CESs, the convenience of infrastructure played a greater role than natural landscape characteristics. Experiential CESs, on the other hand, were affected by natural landscape characteristics themselves. Intellectual CESs had higher requirements for both infrastructure and nature. Inspirational CESs included sensory evaluation indicators, in addition to their focus on natural landscape characteristics and infrastructure, indicating that this category of CESs was more concerned with inner experience. The use of social media data has enriched the dimensions of sensory elements and provided new ideas and information supplements for comprehensively understanding different CESs, thus better supporting the management, planning and protection of rural landscapes.


Assuntos
Ecossistema , Mídias Sociais , China , Cidades , Conservação dos Recursos Naturais , Humanos
2.
Front Plant Sci ; 13: 920054, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720535

RESUMO

Species' phylogeographic patterns reflect the interplay between landscape features, climatic forces, and evolutionary processes. Here, we used two chloroplast DNA (cpDNA) markers (trnL and trnL-F) to explore the role of stepped geomorphology in shaping the phylogeographic structure of Toxicodendron vernicifluum, an economically important tree species widely distributed in East Asia. The range-wide pattern of sequence variation was analyzed based on a dataset including 357 individuals from China, together with published sequences of 92 individuals mainly from Japan and South Korea. We identified five chloroplast haplotypes based on seven substitutions across the 717-bp alignment. A clear east-west phylogeographic break was recovered according to the stepped landforms of mainland China. The wild trees of the western clade were found to be geographically restricted to the "middle step", which is characterized by high mountains and plateaus, while those of the eastern clade were confined to the "low step", which is mainly made up of hills and plains. The two major clades were estimated to have diverged during the Early Pleistocene, suggesting that the cool glacial climate may have caused the ancestral population to retreat to at least two glacial refugia, leading to allopatric divergence in response to long-term geographic isolation. Migration vector analyses based on the outputs of ecological niche models (ENMs) supported a gradual range expansion since the Last Interglacial. Mountain ranges in western China and the East China Sea land bridge were inferred to be dispersal corridors in the western and eastern distributions of T. vernicifluum, respectively. Overall, our study provides solid evidence for the role of stepped geomorphology in shaping the phylogeographic patterns of T. vernicifluum. The resulting east-west genetic discontinuities could persist for a long time, and could occur at a much larger scale than previously reported, extending from subtropical (e.g., the Xuefeng Mountain) to warm-temperate China (e.g., the Taihang Mountain).

3.
Sensors (Basel) ; 22(12)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35746204

RESUMO

In the internet of vehicles (IoVs), vehicle users should provide location information continuously when they want to acquire continuous location-based services (LBS), which may disclose the vehicle trajectory privacy. To solve the vehicle trajectory privacy leakage problem in the continuous LBS, we propose a vehicle trajectory privacy preservation method based on caching and dummy locations, abbreviated as TPPCD, in IoVs. In the proposed method, when a vehicle user wants to acquire a continuous LBS, the dummy locations-based location privacy preservation method under road constraint is used. Moreover, the cache is deployed at the roadside unit (RSU) to reduce the information interaction between vehicle users covered by the RSU and the LBS server. Two cache update mechanisms, the active cache update mechanism based on data popularity and the passive cache update mechanism based on dummy locations, are designed to protect location privacy and improve the cache hit rate. The performance analysis and simulation results show that the proposed vehicle trajectory privacy preservation method can resist the long-term statistical attack (LSA) and location correlation attack (LCA) from inferring the vehicle trajectory at the LBS server and protect vehicle trajectory privacy effectively. In addition, the proposed cache update mechanisms achieve a high cache hit rate.


Assuntos
Internet , Privacidade
4.
FEBS J ; 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35653269

RESUMO

Cancer cells are characterized by altered energetic metabolism with increasing glucose uptake. F806, a 16-membered macrodiolide analogue, has anti-tumour effects on oesophageal squamous cell carcinoma (ESCC) cells. However, its precise anti-tumour mechanism remains unclear. Here, metascape analysis of our previous quantitative proteomics data showed that F806 induced glucose starvation response and inhibited energy production in ESCC cells. The reduced glucose uptake and ATP production were further validated by the fluorescent methods, using glucose-conjugated bioprobe Glu-1-O-DCSN, and the bioluminescent methods, respectively. Consistently, under F806 treatment the AMP-activated protein kinase signalling was activated, and autophagy flux was promoted and more autophagosomes were formed. Moreover, live-cell imaging and immunofluorescence analysis showed that F806 induced GLUT1 plasma membrane dissociation and promoted its internalization and autolysosome accumulation and lysosome degradation. Furthermore, molecular docking studies demonstrated that F806 bound to GLUT1 with a comparable binding energy to that of GLUT1's direct interacting inhibitor cytochalasin B. Amino acid mutation was used to test which residues of GLUT1 may participate in F806 mediated-GLUT1 internalization and degradation, and results showed that Thr137, Asn411 and Trp388 were required for GLUT1 internalization and degradation, respectively. Taken together, these findings shed light on a novel anti-tumour mechanism of F806 by targeting and promoting GLUT1 internalization and further autolysosomal degradation.

5.
Mol Phylogenet Evol ; 174: 107545, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35690374

RESUMO

The utility of transcriptome data in plant phylogenetics has gained popularity in recent years. However, because RNA degrades much more easily than DNA, the logistics of obtaining fresh tissues has become a major limiting factor for widely applying this method. Here, we used Ranunculaceae to test whether silica-dried plant tissues could be used for RNA extraction and subsequent phylogenomic studies. We sequenced 27 transcriptomes, 21 from silica gel-dried (SD-samples) and six from liquid nitrogen-preserved (LN-samples) leaf tissues, and downloaded 27 additional transcriptomes from GenBank. Our results showed that although the LN-samples produced slightly better reads than the SD-samples, there were no significant differences in RNA quality and quantity, assembled contig lengths and numbers, and BUSCO comparisons between two treatments. Using these data, we conducted phylogenomic analyses, including concatenated- and coalescent-based phylogenetic reconstruction, molecular dating, coalescent simulation, phylogenetic network estimation, and whole genome duplication (WGD) inference. The resulting phylogeny was consistent with previous studies with higher resolution and statistical support. The 11 core Ranunculaceae tribes grouped into two chromosome type clades (T- and R-types), with high support. Discordance among gene trees is likely due to hybridization and introgression, ancient genetic polymorphism and incomplete lineage sorting. Our results strongly support one ancient hybridization event within the R-type clade and three WGD events in Ranunculales. Evolution of the three Ranunculaceae chromosome types is likely not directly related to WGD events. By clearly resolving the Ranunculaceae phylogeny, we demonstrated that SD-samples can be used for RNA-seq and phylotranscriptomic studies of angiosperms.

6.
Front Microbiol ; 13: 860009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35602058

RESUMO

Ageratina adenophora, as an invasive and poisonous weed, seriously affects the ecological diversity and development of animal husbandry. Weed management practitioners have reported that it is very difficult to control A. adenophora invasion. In recent years, many researchers have focused on harnessing the endophytes of the plant as a useful resource for the development of pharmacological products for human and animal use. This study was performed to identify endophytes with antibacterial properties from A. adenophora. Agar well diffusion method and 16S rRNA gene sequencing technique were used to screen and identify endophytes with antibacterial activity. The response surface methodology and prep- high-performance liquid chromatography were used to determine the optimizing fermentation conditions and isolate secondary metabolites, respectively. UV-visible spectroscopy, infrared spectroscopy, nuclear magnetic resonance, and high-resolution mass spectrum were used to determine the structures of the isolated metabolites. From the experiment, we isolated a strain of Bacillus velezensis Ea73 (GenBank no. MZ540895) with broad-spectrum antibacterial activity. We also observed that the zone of inhibition of B. velezensis Ea73 against Staphylococcus aureus was the largest when fermentation broth contained 6.55 g/L yeast extract, 6.61 g/L peptone, 20.00 g/L NaCl at broth conditions of 7.95 pH, 51.04 h harvest time, and a temperature of 27.97°C. Two antibacterial peptides, Cyclo (L-Pro-L-Val) and Cyclo (L-Leu-L-Pro), were successfully extracted from B. velezensis Ea73. These two peptides exhibited mild inhibition against S. aureus and Escherichia coli. Therefore, we isolated B. velezensis Ea73 with antibacterial activity from A. adenophora. Hence, its metabolites, Cyclo (L-Pro-L-Val) and Cyclo (L-Leu-L-Pro), could further be developed as a substitute for human and animal antibiotics.

7.
Chemistry ; 28(29): e202201278, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35575480

RESUMO

Invited for the cover of this issue is the group of Biao Kong at Fudan University. The image depicts a hierarchical asymmetric magnetic mesoporous hollow nanorobot that combines the functionalities of magnetic responsiveness, reusability, sustainable motility and durable motion, showing excellent pollutant degradation capability. Read the full text of the article at. 10.1002/chem.202200307.


Assuntos
Fenômenos Magnéticos , Catálise , Humanos , Fenômenos Físicos
8.
BMC Bioinformatics ; 23(Suppl 3): 158, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501680

RESUMO

BACKGROUND: Drug discovery is time-consuming and costly. Machine learning, especially deep learning, shows great potential in quantitative structure-activity relationship (QSAR) modeling to accelerate drug discovery process and reduce its cost. A big challenge in developing robust and generalizable deep learning models for QSAR is the lack of a large amount of data with high-quality and balanced labels. To address this challenge, we developed a self-training method, Partially LAbeled Noisy Student (PLANS), and a novel self-supervised graph embedding, Graph-Isomorphism-Network Fingerprint (GINFP), for chemical compounds representations with substructure information using unlabeled data. The representations can be used for predicting chemical properties such as binding affinity, toxicity, and others. PLANS-GINFP allows us to exploit millions of unlabeled chemical compounds as well as labeled and partially labeled pharmacological data to improve the generalizability of neural network models. RESULTS: We evaluated the performance of PLANS-GINFP for predicting Cytochrome P450 (CYP450) binding activity in a CYP450 dataset and chemical toxicity in the Tox21 dataset. The extensive benchmark studies demonstrated that PLANS-GINFP could significantly improve the performance in both cases by a large margin. Both PLANS-based self-training and GINFP-based self-supervised learning contribute to the performance improvement. CONCLUSION: To better exploit chemical structures as an input for machine learning algorithms, we proposed a self-supervised graph neural network-based embedding method that can encode substructure information. Furthermore, we developed a model agnostic self-training method, PLANS, that can be applied to any deep learning architectures to improve prediction accuracies. PLANS provided a way to better utilize partially labeled and unlabeled data. Comprehensive benchmark studies demonstrated their potentials in predicting drug metabolism and toxicity profiles using sparse, noisy, and imbalanced data. PLANS-GINFP could serve as a general solution to improve the predictive modeling for QSAR modeling.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Aprendizado de Máquina , Relação Quantitativa Estrutura-Atividade , Estudantes
9.
Proc SIAM Int Conf Data Min ; 2022: 720-728, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509686

RESUMO

De novo molecular design is a key challenge in drug discovery due to the complexity of chemical space. With the availability of molecular datasets and advances in machine learning, many deep generative models are proposed for generating novel molecules with desired properties. However, most of the existing models focus only on molecular distribution learning and target-based molecular design, thereby hindering their potentials in real-world applications. In drug discovery, phenotypic molecular design has advantages over target-based molecular design, especially in first-in-class drug discovery. In this work, we propose the first deep graph generative model (FAME) targeting phenotypic molecular design, in particular gene expression-based molecular design. FAME leverages a conditional variational autoencoder framework to learn the conditional distribution generating molecules from gene expression profiles. However, this distribution is difficult to learn due to the complexity of the molecular space and the noisy phenomenon in gene expression data. To tackle these issues, a gene expression denoising (GED) model that employs contrastive objective function is first proposed to reduce noise from gene expression data. FAME is then designed to treat molecules as the sequences of fragments and learn to generate these fragments in autoregressive manner. By leveraging this fragment-based generation strategy and the denoised gene expression profiles, FAME can generate novel molecules with a high validity rate and desired biological activity. The experimental results show that FAME outperforms existing methods including both SMILES-based and graph-based deep generative models for phenotypic molecular design. Furthermore, the effective mechanism for reducing noise in gene expression data proposed in our study can be applied to omics data modeling in general for facilitating phenotypic drug discovery.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35510835

RESUMO

INTRODUCTION: Many multi-genic systemic diseases such as neurological disorders, inflammatory diseases, and the majority of cancers do not have effective treatments yet. Reinforcement learning powered systems pharmacology is a potentially effective approach to designing personalized therapies for untreatable complex diseases. AREAS COVERED: In this survey, state-of-the-art reinforcement learning methods and their latest applications to drug design are reviewed. The challenges on harnessing reinforcement learning for systems pharmacology and personalized medicine are discussed. Potential solutions to overcome the challenges are proposed. EXPERT OPINION: In spite of successful application of advanced reinforcement learning techniques to target-based drug discovery, new reinforcement learning strategies are needed to address systems pharmacology-oriented personalized de novo drug design.

11.
Mater Horiz ; 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35583553

RESUMO

The development of liposome-based drugs was severely limited due to inefficient loading strategies. Herein, we developed a click reaction-mediated loading procedure by designing an enzyme-sensitive maleimide (MAL) tag for ferrying chemotherapeutics into preformed liposomes containing glutathione (GSH). Based on this strategy, various hydrophobic drugs could be encapsulated into liposomes within 5-30 min with encapsulation efficiency >95% and loading capacity of 10-30% (w/w). The entrapped cargo could be slowly released from the liposomes, followed by rapid enzyme-mediated conversion into active drugs to exert antitumor activity under physiological conditions. The resulting drug-loaded liposomes significantly prolonged the blood circulation of cargos and displayed more potent in vivo antitumor efficacy than free drugs at the equitoxic dose. More importantly, this method is a remote drug loading strategy in nature, which is suitable for industrial production. This is the first demonstration of active loading of MAL-tagged chemotherapeutics in liposomes for improved antitumor efficacies, which has the potential to serve as a universal drug loading strategy for the development of liposomal formulations of chemotherapeutics.

12.
Entropy (Basel) ; 24(5)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35626603

RESUMO

In order to meet the requirements of communication security and concealment, as well as to protect marine life, bionic covert communication has become a hot research topic for underwater acoustic communication (UAC). In this paper, we propose a bionic covert UAC (BC-UAC) method based on the time-frequency contour (TFC) of the bottlenose dolphin whistle, which can overcome the safety problem of traditional low signal-noise ratio (SNR) covert communication and make the detected communication signal be excluded as marine biological noise. In the proposed BC-UAC method, the TFC of the bottlenose dolphin whistle is segmented to improve the transmission rate. Two BC-UAC schemes based on the segmented TFC of the whistle, the BC-UAC scheme using the whistle signal with time-delay (BC-UAC-TD) and the BC-UAC scheme using the whistle signal with frequency-shift (BC-UAC-FS), are addressed. The original whistle signal is used as a synchronization signal. Moreover, the virtual time reversal mirror (VTRM) technique is adopted to equalize the channel for mitigating the multipath effect. The performance of the proposed BC-UAC method, in terms of the Pearson correlation coefficient (PCC) and bit error rate (BER), is evaluated under simulated and measured underwater channels. Numerical results show that the proposed BC-UAC method performs well on covertness and reliability. Furthermore, the covertness of the bionic modulated signal in BC-UAC-TD is better than that of BC-UAC-FS, although the reliability of BC-UAC-FS is better than that of BC-UAC-TD.

13.
IEEE Trans Cybern ; PP2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35609104

RESUMO

This article presents a novel singular value decomposition (SVD)-based robust distributed model predictive control (SVD-RDMPC) strategy for linear systems with additive uncertainties. The system is globally constrained and consists of multiple interrelated subsystems with bounded disturbances, each of whom has local constraints on states and inputs. First, we integrate the steady-state target optimizer into the MPC problem through the offset cost function to formulate a modified single optimization problem for tracking changing targets from real-time optimization. Then, the concept of constraint tightening is utilized to enhance the robustness and ensure robust constraint satisfaction in the presence of interferences. On this basis, the SVD method is introduced to decompose the new optimization problem into several independent subsystems on the orthogonal projection space, and a distributed dual gradient algorithm with convergence proved is implemented to obtain the control of each nominal subsystem. The recursive feasibility is then ensured and the tracking ability of the strategy is analyzed. It is verified that for a target, the system can be steered to a neighborhood of the closest possible steady setpoint. At last, the effectiveness of the raised SVD-RDMPC strategy is established in two simulations on building temperature control and load frequency control.

14.
Molecules ; 27(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35630564

RESUMO

Baicalein is a valuable flavonoid isolated from the medicinal plant Scutellaria baicalensis Georgi, which exhibits intensive biological activities, such as anticancer and antiviral activities. However, its production is limited in the root with low yield. In this study, In-Fusion and 2A peptide linker were developed to assemble SbCLL-7, SbCHI, SbCHS-2, SbFNSII-2 and SbCYP82D1.1 genes driven by the AtPD7, CaMV 35S and AtUBQ10 promoters with HSP, E9 and NOS terminators, and were used to engineer baicalein biosynthesis in transgenic tomato plants. The genetically modified tomato plants with this construct synthesized baicalein, ranging from 150 ng/g to 558 ng/g FW (fresh weight). Baicalein-fortified tomatoes have the potential to be health-promoting fresh vegetables and provide an alternative source of baicalein production, with great prospects for market application.


Assuntos
Flavanonas , Lycopersicon esculentum , Flavonoides , Lycopersicon esculentum/genética , Scutellaria baicalensis
15.
ACS Nano ; 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35394286

RESUMO

Hydrogen evolution reaction (HER) through water splitting is a potential technology to realize the sustainable production of hydrogen, yet the tardy water dissociation and costly Pt-based catalysts inhibit its development. Here, a trapping-bonding strategy is proposed to realize the superassembly of surface-enriched Ru nanoclusters on a phytic acid modified nitrogen-doped carbon framework (denoted as NCPO-Ru NCs). The modified framework has a high affinity to metal cations and can trap plenty of Ru ions. The trapped Ru ions are mainly distributed on the surface of the framework and can form Ru nanoclusters at 50 °C with the synergistic effect of vacancies and phosphate groups. By adjusting the content of phytic acid, surface-enriched Ru nanoclusters with adjustable distribution and densities can be obtained. Benefiting from the adequate exposure of the active sites and dense distribution of ultrasmall Ru nanoclusters, the obtained NCPO-Ru NCs catalyst can effectively drive HER in alkaline electrolytes and show an activity (at overpotential of 50 mV) about 14.3 and 9.6 times higher than that of commercial Ru/C and Pt/C catalysts, respectively. Furthermore, the great performance in solar to hydrogen generation through water splitting provides more flexibility for wide applications of NCPO-Ru NCs.

16.
Int J Nanomedicine ; 17: 1647-1657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35418754

RESUMO

Background: The leaves of L. japonica (LLJ) are widely used as medicine in China. It is rich in caffeoylquinic acids, flavonoids and iridoid glycosides and has strong reducing capacities. Therefore, it can be used as a green material to synthesize silver nanoparticles. Methods: LLJ was used as a reducing agent to produce the LLJ-mediated silver nanoparticles (LLJ-AgNPs). The structure and physicochemical properties of LLJ-AgNPs were characterized by ultraviolet spectroscopy (UV-Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and x-ray powder diffraction (XRD). Antioxidant activity of LLJ-AgNPs was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging. Antibacterial activity was determined by 96 well plates (AGAR) gradient dilution, while the anticancer potential was determined by MTT assay. Results: The results showed LLJ-AgNPs had a spherical structure with the maximum UV-Vis absorption at 400 nm. In addition, LLJ-AgNPs exhibited excellent antioxidant properties, where the free radical scavenging rate of LLJ-AgNPs was increased from 39% to 92% at concentrations from 0.25 to 1.0 mg/mL. Moreover, LLJ-AgNPs displayed excellent antibacterial properties against E. coli and Salmonella at room temperature, with minimum inhibitory values of 10-6 and 10-5 g/L, respectively. In addition, the synthetic LLJ-AgNPs exhibited a better inhibition effect in the proliferation of cancer cells (HepG2, MDA-MB -231, and Hela cells). Conclusion: The present study provides a green approach to synthesize LLJ-AgNPs. All those findings illustrated that the produced LLJ-AgNPs can be used as an economical and efficient functional material for further applications in food and pharmaceutical fields.


Assuntos
Lonicera , Nanopartículas Metálicas , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Escherichia coli , Células HeLa , Humanos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Growth Factors ; 40(1-2): 26-36, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35426327

RESUMO

Chinese herbs were widely proposed as a novel approach for renal fibrosis. Icariin has been reported to be involved in a variety of diseases. Unilateral ureteral obstruction (UUO) is a popular experimental model of renal injury, which is often used in the study of renal fibrosis. A UUO mouse model was successfully constructed, and tubular injury and renal fibrosis were observed. Icariin treatment attenuated tubular injury and renal fibrosis in UUO mice. In addition, treatment with Icariin reduced the fibronectin, type I collagen and α-SMA levels in UUO mice. Furthermore, in a transforming growth factor (TGF)-ß1-induced renal fibrosis cell model, icariin treatment also decreased fibronectin, type I collagen and α-SMA expression. Icariin treatment also reversed the enhanced migration of TGF-ß1-induced HK-2 cells. These data indicated that icariin suppressed renal fibrosis in vivo and in vitro. Additionally, icariin treatment suppressed the Notch2/Hes-1 pathway in UUO mice and TGF-ß1-treated HK-2 cells. In summary, this study found that icariin reduced renal fibrosis in vivo and in vitro by inhibiting the Notch2/Hes-1 pathway, which might help to improve therapies for renal fibrosis.


Assuntos
Nefropatias , Obstrução Ureteral , Animais , Colágeno Tipo I , Fibronectinas , Fibrose , Flavonoides , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Camundongos , Fator de Crescimento Transformador beta1/farmacologia , Obstrução Ureteral/complicações , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo
18.
Int J Endocrinol ; 2022: 6556252, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465074

RESUMO

Objective: How to preserve the inferior parathyroid gland (IPTG) in situ during central neck dissection (CND) is the major concern of thyroid surgeons. The "layer of thymus-blood vessel-IPTG" (TBP layer) concept showed to be effective in preserving IPTG. The objective of this study was to identify the origin and course of blood supply to IPTG (IPBS) within the TBP layer and to take key points of operation during CND. Design: This is a retrospective control study. Participants. Patients who underwent thyroidectomy plus CND using the TBP layer concept and conventional technique between 2017 and 2019 were enrolled. Measurements. The origin and course of IPBS in relation to recurrent laryngeal nerve (RLN) and thymus and prevalence of hypoparathyroidism were detected. Results: A total of 71.3% of IPTGs (251 of 352) were supplied by ITA branches, defined as type A. Type A was further divided into Types A1 (branches of ITA, coursing laterally to the RLN (53.1%, 187 of 352)) and A2 (branches of ITA, traversing medially to the RLN (18.2%, 64 of 352)). Type A2 was more common on the right side than on the left side (P < 0.001). Fifty-five (15.6%) IPTG feeding vessels originated from the thymus or mediastinum. Nineteen (5.4%) IPTGs were supplied by branches of the superior thyroid artery. The incidence of transient hypoparathyroidism decreased from 45.7% to 3.6% (P < 0.001), in the TBP layer group compared with the conventional technique group. Conclusion: The origin and course of IPBS follow a definite pattern. This mapping and precautions help surgeons optimize intraoperative manipulations for better preservation of IPBS during CND.

19.
Animals (Basel) ; 12(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35454189

RESUMO

Identifying latitudinal variation in the pattern of temperature-dependent sex determination (TSD) may provide insight into the evolution of sex determining system in vertebrates, but such studies remain limited. Here, we quantified TSD patterns of three geographically separated populations of the Japanese gecko (Gekko japonicus) along the latitudinal cline of China. We incubated gecko eggs from the three populations at constant temperatures of 24, 26, 28, 30, and 32 °C to quantify the TSD pattern. Our study demonstrated that G. japonicus exhibited a FMF pattern of TSD, with the low and high incubation temperatures yielding significantly female-biased hatchlings, and the medium temperatures producing male-biased hatchlings. More interestingly, we found latitudinal variations in the TSD pattern in terms of pivotal temperatures (Tpivs), transitional range of temperatures (TRT), and the sex ratios at the medium temperatures. The Tpivs for the low-latitude population were lower than those for the two high-latitude populations. The low-latitude population has a narrower FM TRT, but a wider MF TRT. The sex ratio is almost 50:50 for the low-latitude population when eggs were incubated from 26 to 30 °C. Conversely, the sex ratio is male-biased for the two high-latitude populations at 28 or 30 °C. Therefore, G. japonicus may provide an interesting system to explore the evolution of TSD in reptiles given the diversity of TSD patterns among populations.

20.
Angew Chem Int Ed Engl ; : e202203955, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35441462

RESUMO

In natural photosynthesis, the architecture of multiproteins integrates more chromophores than redox centers and simultaneously creates a well-controlled environment around the active site. Herein, we demonstrate that these features can be emulated in a prototype hydrogen-bonded organic framework (HOF) through simply varying the proportion of metalated porphyrin in the structure. Further studies demonstrate that changing the metalloporphyrin content not only realizes a fine tuning of the photosensitizer/catalyst ratio, but also alters the microenvironment surrounding the active site and the charge separation efficiency. As a result, the obtained material achieves the challenging overall CO2 reduction with a high HCOOH production rate (29.8 µmol g-1 h-1 , scavenger free), standing out from existing competitors. This work unveils that the degree of metalation is vital to the catalytic activity of the porphryinic framework, presenting as a new strategy to optimize the performance of heterogeneous catalysts.

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