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1.
Mol Biol Evol ; 2024 Jun 06.
Article En | MEDLINE | ID: mdl-38842255

The origins and extreme morphological evolution of the modern dog breeds are poorly studied because the founder populations are extinct. Here, we analyse eight 100-200 years old dog fur samples obtained from traditional North Swedish clothing, to explore the origin and artificial selection of the modern Nordic Lapphund and Elkhound dog breeds. Population genomic analysis confirmed the Lapphund and Elkhound breeds to originate from the local dog population, and showed a distinct decrease in genetic diversity in agreement with intense breeding. We identified eleven genes under positive selection during the breed development. In particular, the MSRB3 gene, associated with breed-related ear morphology, was selected in all Lapphund and Elkhound breeds, and functional assays showed that a SNP mutation in the 3'UTR region suppresses its expression through miRNA regulation. Our findings demonstrate analysis of near-modern dog artifacts as an effective tool for interpreting the origin and artificial selection of the modern dog breeds.

2.
Front Neurol ; 14: 1187813, 2023.
Article En | MEDLINE | ID: mdl-37602242

Gerstmann-Sträussler-Scheinker syndrome (GSS) is a rare genetic prion disease caused by a mutation in the prion protein (PRNP) gene. It is typically characterized by progressive cerebellar ataxia and slowly progressive dementia. We present a case study of the GSS from China in which a 45-year-old male with a progressive gait and balance disorder developed cerebellar ataxia onset but was misdiagnosed as spinocerebellar ataxia (SCA) for 2 years. The patient's clinical, electrophysiological, and radiological data were retrospectively analyzed. Examination revealed ataxia, dysarthria, muscle weakness, areflexia in lower limbs, including a pyramidal sign, whereas cognitive decline was insignificant. His late mother had a similar unsteady gait. An electroencephalogram (EEG) showed normal findings, and 14-3-3 protein was negative. A brain MRI was performed for global brain atrophy and ventricular enlargement. Positron emission tomography-computed tomography (PET-CT) (18F-fluoro-2-deoxy-d-glucose, FDG) images showed mild to moderate decreased glucose metabolism in the left superior parietal lobe and left middle temporal lobe. According to genetic testing, his younger brother also had the P102L variant in the PRNP gene. This single case adds to the clinical and genetic phenotypes of GSS.

4.
J Am Chem Soc ; 145(31): 17164-17175, 2023 Aug 09.
Article En | MEDLINE | ID: mdl-37440344

One of the hallmarks of multicomponent metal-organic frameworks (MOFs) is to finely tune their active centers to achieve product selectivity. In particular, obtaining bimetallic MOF hollow structures with precisely tailored redox centers under the same topology is still challenging despite a recent surge of such efforts. Herein, we present an engineering strategy named "cluster labilization" to generate hierarchically porous MOF composites with hollow structures and tunable active centers. By partially replacing zirconium with cerium in the hexanuclear clusters of UiO-66, unevenly distributed yolk-shell structures (YSS) were formed. Through acid treatment or annealing of the YSS precursor, single-shell hollow structures (SSHS) or double-shell hollow structures (DSHS) can be obtained, respectively. The active centers in SSHS and DSHS differ in their species, valence, and spatial locations. More importantly, YSS, SSHS, and DSHS with distinct active centers and microenvironments exhibit tunable catalytic activity, reversed selectivity, and high stability in the tandem reaction and the photoreaction.

5.
Chem Commun (Camb) ; 59(18): 2541-2559, 2023 Feb 28.
Article En | MEDLINE | ID: mdl-36749364

Recently, Zr- and Ti-based metal-organic frameworks (MOFs) have gathered increasing interest in the field of chemistry and materials science, not only for their ordered porous structure, large surface area, and high thermal and chemical stability, but also for their various potential applications. Particularly, the unique features of Zr- and Ti-based MOFs enable them to be a highly versatile platform for catalysis. Although much effort has been devoted to developing Zr- and Ti-based MOF materials, they still suffer from difficulties in targeted synthesis, especially for Ti-based MOFs. In this Feature Article, we discuss the evolution of Zr- and Ti-based MOFs, giving a brief overview of their synthesis and structures. Furthermore, the catalytic uses of Zr- and Ti-based MOF materials in the previous 3-5 years have been highlighted. Finally, perspectives on the Zr- and Ti-based MOF materials are also proposed. This work provides in-depth insight into the advances in Zr- and Ti-based MOFs and boosts their catalytic applications.

7.
Opt Express ; 30(21): 39142-39151, 2022 Oct 10.
Article En | MEDLINE | ID: mdl-36258461

Water-based coherent detection of broadband terahertz (THz) wave has been recently proposed with superior performances, which can alleviate the limited detection bandwidth and high probe laser energy requirement in the solid- and air-based detection schemes, respectively. Here, we demonstrate that the water-based detection method can be extended to the aqueous salt solutions and the sensitivity can be significantly enhanced. The THz coherent detection signal intensity scales linearly with the third-order nonlinear susceptibility χ(3) or quadratically with the linear refractive index η0 of the aqueous salt solutions, while the incoherent detection signal intensity scales quadratically with χ(3) or quartically with η0, proving the underlying mechanism is the four-wave mixing. Both the coherent and incoherent detection signal intensities appear positive correlation with the solution concentration. These results imply that the liquid-based THz detection scheme could provide a new technique to measure χ(3) and further investigate the physicochemical properties in the THz band for various liquids.

8.
World J Clin Cases ; 10(14): 4535-4540, 2022 May 16.
Article En | MEDLINE | ID: mdl-35663070

BACKGROUND: Regular abdominal massage can be used to treat digestive symptoms such as bloating and constipation and is reported to reduce abdominal discomfort, improve digestive function, and increase the quality of life, without serious adverse effects. Isolated pancreatic injury is rare, and most often occurs during severe trauma such as steering wheel impact injury. To our knowledge, pancreatic injury caused by massage has not yet been reported in the literature. CASE SUMMARY: A 57-year-old woman was referred to our hospital for acute abdominal pain and transient syncope. On examination, she had low hemoglobin concentration and a high white blood cell count and neutrophil percentage. Plain computed tomography of the abdomen revealed a substantial hemorrhage in the abdominal cavity. A large amount of exudate in the pancreatic area was considered a hematoma. Preoperative diagnosis was difficult. Her hemoglobin and blood pressure did not rise even after blood. We suspected progressive bleeding in the abdominal cavity and urgently performed exploratory laparotomy. During the operation, the pancreas was confirmed to be ruptured; hence, spleen-preserving pancreatic body and tail resection were performed. A pancreatic fistula was found on the 15th d after the operation, and the patient was discharged with a drainage tube on the 24th d after active treatment. Subsequently, it was discovered that the patient had undergone a vigorous abdominal massage the day before the abdominal pain began. To our knowledge, this is the first report of isolated pancreatic injury and massive abdominal hemorrhage caused by abdominal massage. CONCLUSION: Our findings indicate that any action that increases intra-abdominal pressure may cause internal organ damage. We also review similar cases reported in the literature.

9.
Chemosphere ; 297: 134215, 2022 Jun.
Article En | MEDLINE | ID: mdl-35248597

In this work, a desulfurization method using natural amino acid salts (AAS), which can be green prepared by biological fermentation, is proposed to remove H2S from raw biogas. Biogas purification and fertilizer production can be simultaneously achieved to close sulfur recycle. The reaction kinetic characteristics of H2S absorption with three kinds of AAS, including potassium ß-alaninate (PA), potassium sarcosinate (PS) and potassium l-prolinate (PP) are first studied. Kinetic parameters including orders of reaction, rate constants, pre-exponential factors and activation energies are given. AAS absorbent exhibits good potential for biogas desulfurization. Higee (high gravity) technology is utilized to intensify H2S removal. The effects of operating conditions on H2S removal efficiency are investigated and PP shows the best desulfurization performance. The phytotoxicity of AAS and amino acid salt sulfide (AASS) is assessed by the germination index of mungbean seeds. PP and its salt sulfide (PPS) show relatively low phytotoxicity and their allowable agricultural feeding concentrations are below 0.08 M and 0.04 M, respectively. The desulfurization method demonstrates a green route for biogas purification to achieve sulfur recycle.


Biofuels , Hydrogen Sulfide , Amino Acids , Bioreactors , Hydrogen Sulfide/chemistry , Potassium , Salts , Sulfides , Sulfur/metabolism
10.
Dalton Trans ; 51(15): 5782-5787, 2022 Apr 12.
Article En | MEDLINE | ID: mdl-35353878

A triphenylphosphine-modified tetra-nuclear Cu(I) coordinated cluster was constructed for enhanced chemodynamic therapy (CDT) by increasing the number of metal centers. Once inside human bladder cancer (T24) cells, a larger amount of copper accumulated compared with the mono-nuclear Cu(I) complex; the additional copper could generate more •OH and then induce more obvious apoptosis via a Fenton-like reaction, thus further increasing the tumor inhibition effect and ultimately improving the CDT efficiency.


Copper , Neoplasms , Cell Line, Tumor , Humans , Hydrogen Peroxide , Organophosphorus Compounds
11.
Phys Rev Lett ; 128(9): 093902, 2022 Mar 04.
Article En | MEDLINE | ID: mdl-35302828

Both solids and gases have been demonstrated as the materials for terahertz (THz) coherent detection. The gas-based coherent detection methods require a high-energy probe laser beam and the detection bandwidth is limited in the solid-based methods. Whether liquids can be used for THz detection and relax these problems has not yet been reported, which becomes a timely and interesting topic due to the recent observation of efficient THz wave generation in liquids. Here, we propose a THz coherent detection scheme based on liquid water. When a THz pulse and a fundamental laser beam are mixed on a free-flowing water film, a second harmonic (SH) beam is generated as the plasma is formed. Combining this THz-induced SH beam with a control SH beam, we successfully achieve the time-resolved waveform of the THz field with the frequency range of 0.1-18 THz. The required probe laser energy is as low as a few microjoules. The sensitivity of our scheme is 1 order of magnitude higher than that of the air-based method under comparable detection conditions. The scheme is sensitive to the THz polarization and the phase difference between the fundamental and control SH beams, which brings direct routes for optimization and polarization sensitive detection. Energy scaling and polarization properties of the THz-induced beam indicate that its generation can be attributed to a four-wave mixing process. This generation mechanism makes simple relationships among the probe laser, THz-induced SH, and THz field, favorable for robustness and flexibility of the detection device.

12.
ACS Appl Mater Interfaces ; 14(2): 3476-3484, 2022 Jan 19.
Article En | MEDLINE | ID: mdl-34985879

Supports can widely affect or even dominate the catalytic activity and selectivity of nanoparticles because atomic geometry and electronic structures of active sites can be regulated, especially at the interface of nanoparticles and supports. However, the underlying mechanisms of most systems are still not fully understood yet. Herein, we construct the interface of Co3O4/TiO2 to boost ammonium perchlorate (AP) catalytic decomposition. This catalyst shows enhanced catalytic performance. With the addition of 2 wt % Co3O4/TiO2 catalysts, AP decomposition peak temperature decreases from 435.7 to 295.0 °C and activation energy decreases from 211.5 to 137.7 kJ mol-1. By combining experimental and theoretical studies, we find that Co3O4 nanoparticles can be strongly anchored onto TiO2 supports accompanied by charge transfer. Moreover, at the interfaces in the Co3O4/TiO2 nanostructure, NH3 adsorption can be enhanced through hydrogen bonds. Our research studies provide new insights into the promotion effects of the nanoparticle/support system on the AP decomposition process and inspire the design of efficient catalysts.

13.
Article En | MEDLINE | ID: mdl-34925531

Slow transit constipation (STC) is a common type of constipation with a high incidence rate and a large number of patients. We aimed to investigate the therapeutic effects and potential mechanism of paeoniflorin (PAE) on loperamide-induced Sprague Dawley (SD) rat constipation models. Rats with loperamide-induced constipation were orally administered different concentrations of PAE (10, 20, or 40 mg/kg). In vitro, enterochromaffin (EC)-like RIN-14B cells were treated with 20, 40, or 80 µg/ml PAE. We found that PAE treatment significantly improved the symptoms of constipation and increased the intestinal transit rate. Hematoxylin and eosin (H&E) staining showed that PAE alleviated colonic tissue pathological damage. Besides, our results implied that PAE concentration-dependently promoted the content of 5-hydroxytryptamine (5-HT) catalyzed by tryptophan hydroxylase (Tph)-1 in the serum of loperamide-induced rats and in RIN-14B cells. Western blot and immunofluorescence (IF) stain indicated that PAE also promoted the expression of G protein-coupled BA receptor 1 (TGR5), transient receptor potential ankyrin 1 (TRPA1), phospholipase C (PLC)-γ1, and phosphatidylinositol 4,5-bisphosphate (PIP2) in vivo and in vitro. RIN-14B cells were cotreated with a TGR5 inhibitor (SBI-115) to explore the mechanism of PAE in regulating the 5-HT secretion. We observed inhibition of TGR5 reversed the increase of 5-HT secretion induced by PAE in RIN-14B cells. We provided evidence that PAE could promote 5-HT release from EC cells and improve constipation by activating the TRPA1 channel and PLC-γ1/PIP2 signaling. Thus, PAE may provide therapeutic effects for patients with STC.

14.
Antioxidants (Basel) ; 10(2)2021 Jan 28.
Article En | MEDLINE | ID: mdl-33525391

In mammalian ovaries, the avascular environment within follicular cavity is supposed to cause hypoxic status in granulosa cells (GCs), leading to apoptotic cell death accompanied by cumulative reactive oxygen species (ROS) production. Melatonin (N-acetyl-5-methoxytryptamine, MT), a broad-spectrum antioxidant that exists in porcine follicle fluid, was suggested to maintain GCs survival under stress conditions. In this study, using the established hypoxic model (1% O2) of cultured porcine GCs, we explored the effect of MT on GCs apoptosis. The results showed that MT restored cell viability and reduced the apoptosis of GCs during hypoxia exposure. In addition, GCs treated with MT exhibited decreased ROS levels and increased expression of antioxidant enzymes including heme oxygenase-1 (HO-1), glutathione S-transferase (GST), superoxide dismutase 1 (SOD1), and catalase (CAT) upon hypoxia incubation. Moreover, the hypoxia-induced expression of cleaved caspase 3, 8, and 9 was significantly inhibited after MT treatment. In contrast, blocking melatonin receptor 2 (MTNR1B) with a competitive antagonist 4-phenyl-2-propionamidotetralin (4P-PDOT) diminished the inhibitory effects of MT on caspase 3 activation. By detecting levels of protein kinase (PKA), a downstream kinase of MTNR1B, we further confirmed the involvement of MT-MTNR1B signaling in mediating GCs protection during hypoxia stress. Together, the present data provide mechanistic evidence suggesting the role of MT in defending GCs from hypoxia-induced apoptosis.

15.
Nat Prod Res ; 35(23): 5415-5419, 2021 Dec.
Article En | MEDLINE | ID: mdl-32662302

Chemical composition, in vitro antioxidant, DNA damage protective, nitrite scavenging activities, as well as antibacterial activity of Amomum kravanh fruits essential oil against several foodborne pathogens, were investigated. Results showed that the 1,8-cineole (58.53%) was found as the main component, followed by α-pinene (8.32%), α-terpinyl acetate (4.68%), α-terpinolene (4.12%), α-terpinene (3.55%), ß-pinene (3.49%). The essential oil had significant antioxidant activity, the protective effect against DNA damage, and nitrite scavenging activity. These biological activities were dose-dependent, increasing with the higher dosage in a certain concentration range. The essential oil exhibited antibacterial activity against four foodborne pathogens with the minimum inhibitory concentration (MIC) of 5-10 mg/mL and minimum bactericide concentration (MBC) of 10-20 mg/mL. The antibacterial effects of essential oil were greater against Gram-positive bacteria as compared to Gram-negative bacteria. These results suggested that essential oil could be available as a significant natural agent for prevention of food oxidation and spoilage.


Amomum , Oils, Volatile , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , DNA Damage , Microbial Sensitivity Tests , Nitrites , Oils, Volatile/pharmacology
16.
Sci Rep ; 10(1): 8876, 2020 06 01.
Article En | MEDLINE | ID: mdl-32483369

Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 µg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk).


Anti-Bacterial Agents/chemistry , Crataegus/chemistry , Plant Extracts/chemistry , Anti-Bacterial Agents/pharmacology , Catechin/pharmacology , Cell Wall/drug effects , Cell Wall/physiology , Chlorogenic Acid/pharmacology , Chromatography, High Pressure Liquid , Crataegus/metabolism , Flavonoids/chemistry , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Membrane Potentials/drug effects , Microbial Sensitivity Tests , Phenols/chemistry , Plant Extracts/pharmacology , Reactive Oxygen Species/metabolism
17.
Opt Express ; 28(6): 7843-7857, 2020 Mar 16.
Article En | MEDLINE | ID: mdl-32225420

The effect of the growth of ambient pressures on the penetration of laser welded molybdenum (Mo) alloy was explored. It was found that when ambient pressure rose from 0.1 MPa to 1.8 MPa, the penetration of base metal (BM) was significantly reduced, which was only 17% of that obtained under ambient pressure of 0.1 MPa. Moreover, the mechanism underlying the significant reduction of the penetration of BM was analyzed. At first, by using a high-resolution scanning electron microscope (SEM), the size and the number of nano-sized metallic particles generated during laser welding under different ambient pressures were surveyed. Furthermore, the scattering and absorption of the nano-sized metallic particles for laser energy under different ambient pressures were investigated; afterwards, by applying a high-speed camera and a spectrometer, the transient behaviors and spectral signals of plasmas during fiber laser spot welding under different ambient pressures were monitored. On this basis, the inverse bremsstrahlung absorption of plasmas for laser energy under different ambient pressures was explored; finally, fiber laser spot welding test was carried out on glass/metal composite samples under different ambient pressures to survey the influence of the change of ambient pressure on dynamic behaviors of the molten pool during the welding.

18.
J Colloid Interface Sci ; 571: 100-108, 2020 Jul 01.
Article En | MEDLINE | ID: mdl-32182495

The cellulose, which is one of the most abundant solid by-products of agriculture and forestry industry, has been successfully tested for the synthesis of nitrogen and phosphorus co-doped carbon-based metal-free catalysts (NPC) via freeze-drying the mixture of cellulose crystallite and ammonium phosphate, followed by annealing of the hydrogel under nitrogen atmosphere at 800 °C for 2 h. Different techniques including TEM, SEM, FTIR and XPS spectroscopy have been applied to characterize the as-prepared NPC, which presents flake-like morphology with N and P doping levels of 4.3 atom% and 10.66 atom%, respectively. The NPC exhibits excellent catalytic activity for the reduction of p-nitrophenol (p-NP). The turnover frequency (TOF) of the reduction of p-NP is as high as 2 × 10-5 mmol·mg-1·min-1 and the apparent kinetic rate constant was calculated as 0.0394 min-1 at room temperature. The catalytic mechanism is proposed by combining the density functional theory calculation and analysis of the experimental results. These findings open up new possibilities of valorization for cellulose-based by-product and treatment of p-NP-based wastewater.


Carbon/chemistry , Cellulose/chemistry , Nitrogen/chemistry , Nitrophenols/chemistry , Phosphorus/chemistry , Catalysis , Density Functional Theory , Oxidation-Reduction , Particle Size , Surface Properties
19.
Nat Commun ; 11(1): 671, 2020 02 03.
Article En | MEDLINE | ID: mdl-32015346

Dingoes are wild canids living in Australia, originating from domestic dogs. They have lived isolated from both the wild and the domestic ancestor, making them a unique model for studying feralization. Here, we sequence the genomes of 10 dingoes and 2 New Guinea Singing Dogs. Phylogenetic and demographic analyses show that dingoes originate from dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia around 8300 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identifies 50 positively selected genes enriched in digestion and metabolism, indicating a diet change during feralization of dingoes. Thirteen of these genes have shifted allele frequencies compared to dogs but not compared to wolves. Functional assays show that an A-to-G mutation in ARHGEF7 decreases the endogenous expression, suggesting behavioral adaptations related to the transitions in environment. Our results indicate that the feralization of the dingo induced positive selection on genomic regions correlated to neurodevelopment, metabolism and reproduction, in adaptation to a wild environment.


Canidae/classification , Canidae/genetics , Genomics , Phylogeny , Animal Migration , Animals , Asia, Southeastern , Australia , DNA, Mitochondrial/analysis , Dogs/classification , Dogs/genetics , Genetic Variation , Genetics, Population , Genome, Mitochondrial , New Guinea , Polymorphism, Single Nucleotide , Rho Guanine Nucleotide Exchange Factors/genetics , Wolves/classification , Wolves/genetics
20.
J Am Chem Soc ; 140(6): 2363-2372, 2018 02 14.
Article En | MEDLINE | ID: mdl-29345141

Sufficient pore size, appropriate stability, and hierarchical porosity are three prerequisites for open frameworks designed for drug delivery, enzyme immobilization, and catalysis involving large molecules. Herein, we report a powerful and general strategy, linker thermolysis, to construct ultrastable hierarchically porous metal-organic frameworks (HP-MOFs) with tunable pore size distribution. Linker instability, usually an undesirable trait of MOFs, was exploited to create mesopores by generating crystal defects throughout a microporous MOF crystal via thermolysis. The crystallinity and stability of HP-MOFs remain after thermolabile linkers are selectively removed from multivariate metal-organic frameworks (MTV-MOFs) through a decarboxylation process. A domain-based linker spatial distribution was found to be critical for creating hierarchical pores inside MTV-MOFs. Furthermore, linker thermolysis promotes the formation of ultrasmall metal oxide nanoparticles immobilized in an open framework that exhibits high catalytic activity for Lewis acid-catalyzed reactions. Most importantly, this work provides fresh insights into the connection between linker apportionment and vacancy distribution, which may shed light on probing the disordered linker apportionment in multivariate systems, a long-standing challenge in the study of MTV-MOFs.

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