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1.
Nature ; 601(7894): 562-567, 2022 01.
Article in English | MEDLINE | ID: mdl-35082417

ABSTRACT

In conventional superconductors, the phase transition into a zero-resistance and perfectly diamagnetic state is accompanied by a jump in the specific heat and the opening of a spectral gap1. In the high-transition-temperature (high-Tc) cuprates, although the transport, magnetic and thermodynamic signatures of Tc have been known since the 1980s2, the spectroscopic singularity associated with the transition remains unknown. Here we resolve this long-standing puzzle with a high-precision angle-resolved photoemission spectroscopy (ARPES) study on overdoped (Bi,Pb)2Sr2CaCu2O8+δ (Bi2212). We first probe the momentum-resolved electronic specific heat via spectroscopy and reproduce the specific heat peak at Tc, completing the missing link for a holistic description of superconductivity. Then, by studying the full momentum, energy and temperature evolution of the spectra, we reveal that this thermodynamic anomaly arises from the singular growth of in-gap spectral intensity across Tc. Furthermore, we observe that the temperature evolution of in-gap intensity is highly anisotropic in the momentum space, and the gap itself obeys both the d-wave functional form and particle-hole symmetry. These findings support the scenario that the superconducting transition is driven by phase fluctuations. They also serve as an anchor point for understanding the Fermi arc and pseudogap phenomena in underdoped cuprates.

2.
Mol Biol Evol ; 41(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38376543

ABSTRACT

In mammalian research, it has been debated what can initiate an evolutionary tradeoff between different senses, and the phenomenon of sensory tradeoff in rodents, the most abundant mammalian clade, is not evident. The Nile rat (Arvicanthis niloticus), a murid rodent, recently adapted to a diurnal niche through an evolutionary acquisition of daylight vision with enhanced visual acuity. As such, this model provides an opportunity for a cross-species investigation where comparative morphological and multi-omic analyses of the Nile rat are made with its closely related nocturnal species, e.g. the mouse (Mus musculus) and the rat (Rattus norvegicus). Thus, morphological examinations were performed, and evolutionary reductions in relative sizes of turbinal bone surfaces, the cribriform plate, and the olfactory bulb were discovered in Nile rats. Subsequently, we compared multiple murid genomes, and profiled olfactory epithelium transcriptomes of mice and Nile rats at various ages with RNA sequencing. The results further demonstrate that, in comparison with mouse olfactory receptor (OR) genes, Nile rat OR genes have experienced less frequent gain, more frequent loss, and more frequent expression reduction during their evolution. Furthermore, functional degeneration of coding sequences in the Nile rat lineage was found in OR genes, yet not in other genes. Taken together, these results suggest that acquisition of improved vision in the Nile rat has been accompanied by degeneration of both olfaction-related anatomical structures and OR gene repertoires, consistent with the hypothesis of an olfaction-vision tradeoff initiated by the switch from a nocturnal to a diurnal lifestyle in mammals.


Subject(s)
Circadian Rhythm , Murinae , Animals , Circadian Rhythm/physiology , Mammals , Genome
3.
J Am Chem Soc ; 146(4): 2333-2338, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38241610

ABSTRACT

Odd-electron bonds, i.e., the two-center, three-electron (2c/3e), or one-electron (2c/1e) bonds, have attracted tremendous interest owing to their novel bonding nature and radical properties. Herein, complex [K(THF)6][LSn:···Sn:L] (1), featuring the first and unsupported 2c/1e Sn···Sn σ-bond with a long distance (3.2155(9) Å), was synthesized by reduction of stannylene [LSn:] (L = N,N-dpp-o-phenylene diamide) with KC8. The one-electron Sn-Sn bond in 1 was confirmed by the crystal structure, DFT calculations, EPR spectroscopy, and reactivity studies. This compound can be viewed as a stabilized radical by delocalizing to two metal centers and can readily mediate radical reactions such as C-C coupling of benzaldehyde.

4.
Histopathology ; 84(5): 810-821, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38192219

ABSTRACT

AIMS: The neutrophil-lymphocyte ratio (NLR) is a systemic reflection of cancer-associated inflammation and a prognostic marker for breast cancer. For the local tumour microenvironment, tumour-infiltrating lymphocytes (TILs) and tumour-associated macrophages (TAMs) are also highly correlated with breast cancer survival. This study aimed to explore the relationship between the circulating and local immune microenvironment, and to further delineate the prognostic role of NLR in breast cancer patients receiving neoadjuvant chemotherapy (NAC). METHODS: A cohort of breast cancer patients receiving NAC with subsequent surgery was retrieved. Clinical data were reviewed. Histological slides and CD8 immunohistochemistry from biopsy (pre-chemotherapy) and excision (postchemotherapy) specimens were assessed for TILs and TAMs. RESULTS: A total of 146 patients were included. There was a significant positive correlation between pre- and postsurgery NLR at a cut-off of 2.6 (median pre-chemotherapy NLR) (P < 0.001). NLR pre-chemotherapy was associated positively with necrosis on biopsy (P = 0.027) and excision (P = 0.021) and TAMs on excision (P = 0.049). NLR 1 year postsurgery was associated with high tumour stage (P = 0.050) and low histological grade (P = 0.008). TIL count was lower in NLR-high cases at almost all time-points by histological assessment and CD8 immunostaining (P < 0.050). In multivariate analysis, postsurgery NLR is an independent predictor for overall survival [OS; hazard ratio (HR) = 9.524, P < 0.001], breast cancer-specific survival (BCSS) (HR = 10.059, P = 0.001) and disease-free survival (DFS; HR = 2.824, P = 0.016). CONCLUSIONS: The association between NLR with tumour necrosis, TAMs and TILs illustrates an interaction between the circulating and local immune microenvironment. Late NLR is a strong indicator of outcome and may be useful for prognostication and disease monitoring.


Subject(s)
Breast Neoplasms , Lymphocytes, Tumor-Infiltrating , Humans , Female , Lymphocytes, Tumor-Infiltrating/pathology , Breast Neoplasms/pathology , Neutrophils/pathology , Neoadjuvant Therapy , Tumor-Associated Macrophages/pathology , Lymphocytes/pathology , Prognosis , Necrosis/pathology , Retrospective Studies , Tumor Microenvironment
5.
Article in English | MEDLINE | ID: mdl-38330584

ABSTRACT

Objective: Acute pancreatitis (AP) is a process of acute inflammation and cell damage of the pancreas. Gallstones and alcohol abuse are the most common cause for AP. Drug-induced pancreatitis (DIP), accounting for less than 3% of the AP, has become increasingly recognized as an additional and vitally important etiology of acute pancreatitis. Sertraline is an antidepressant of the selective serotonin reuptake inhibitor (SSRI)class that has a range of side effects even when used at the recommended dose. A recognized but rare association in teenagers is acute pancreatitis. The report is of a 15-year-old male teenager with a history of depression who developed acute pancreatitis following self-overdose of his sertraline prescription. Case Report: A 15-year-old teenager with an overdose of sertraline, which was the only medication he took, presented abdominal pain, nausea, and vomiting. The common causes of alcohol consumption, gallstones, biliary duct obstruction, malignancy, trauma, hypertriglyceridemia, and hypercalcemia were eliminated. The increased level of amylase and parenchymal edema of the pancreas revealed in computed tomography supported the diagnosis of acute pancreatitis. After discontinuation of the drug and conventional acute pancreatitis treatment, he recovered evenly. Conclusion: With the increasing use of antidepressant medications in patients of teenagers, this report is a reminder that clinicians should be aware of the association between SSRIs such as sertraline, particularly in cases of overdose, and the development of acute pancreatitis.

6.
Sensors (Basel) ; 24(4)2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38400305

ABSTRACT

A seafloor observation network (SON) consists of a large number of heterogeneous devices that monitor the deep sea and communicate with onshore data centers. Due to the long-distance information transmission and the risk of malicious attacks, ensuring the integrity of data in transit is essential. A cryptographically secure frame check sequence (FCS) has shown great advantages in protecting data integrity. However, the commonly used FCS has a collision possibility, which poses a security risk; furthermore, reducing the encryption calculation cost is a challenge. In this paper, we propose a secure, lightweight encryption scheme for transmitted data inspired by mimic defense from dynamic heterogeneous redundancy theory. Specifically, we use dynamic keys to encrypt a data block and generate multiple encrypted heterogeneous blocks for transmission. These continuously changing encrypted data blocks increase the confusion regarding the original encoded data, making it challenging for attackers to interpret and modify the data blocks. Additionally, the redundant information from the multiple blocks can identify and recover tampered data. Our proposed scheme is suitable for resource-constrained environments where lightweight encryption is crucial. Through experimental demonstrations and analysis methods, we determine the effectiveness of our encryption scheme in reducing computational costs and improving security performance to protect data integrity.

7.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2501-2511, 2024 May.
Article in Zh | MEDLINE | ID: mdl-38812154

ABSTRACT

This study established a convenient, rapid, and sensitive ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) method for simultaneous determination of magnoflorine,(R)-coclaurine, vicenin Ⅱ, isospinosin, spinosin, swertisin, N-nornuciferine, 6-feruloylspinosin, and jujuboside B in beagle dog plasma after oral administration of fried Ziziphi Spinosae Semen(FZSS) extract. The Waters HSS-T3 C_(18) column(2.1 mm×100 mm, 1.8 µm) was used. The methanol-aqueous solution(containing 0.01% formic acid) was adopted as the mobile phase for gradient elution. The nine components and two internal standards were completely separated within 8 min. The mass spectrometry detection was performed in multiple reaction monitoring(MRM) mode by positive and negative ion switching of electrospray ionization. The analytical method was validated in terms of specificity, selectivity, linear range, accuracy, precision, recovery, matrix effect, and stability. It could meet the requirement of pharmacokinetic research after oral administration of FZSS extract to beagle dogs. The results showed that the time to reach the peak concentration(T_(max)) of magnoflorine,(R)-coclaurine, vicenin Ⅱ, isospinosin, spinosin, 6-feruloylspinosin, and jujuboside B was 2.40-3.20 h, and the elimination halflife(t_(1/2)) was 2.08-6.79 h after a single-dose oral administration of FZSS to beagle dogs. The exposure of magnoflorine and spinosin was high, with a peak concentration(C_(max)) of 76.7 and 31.5 ng·mL~(-1) and an area under the curve(AUC_(0-∞)) of 581 and 315 ng·h·mL~(-1), respectively. The exposure of the remaining five compounds was lower, with a C_(max) of 0.81-13.0 ng·mL~(-1) and an AUC_(0-∞) of 6.00-106 ng·h·mL~(-1). This study provides a reference for the follow-up research of FZSS.


Subject(s)
Drugs, Chinese Herbal , Tandem Mass Spectrometry , Ziziphus , Animals , Dogs , Tandem Mass Spectrometry/methods , Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/pharmacokinetics , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/administration & dosage , Ziziphus/chemistry , Male , Liquid Chromatography-Mass Spectrometry
8.
Chemphyschem ; 24(7): e202200789, 2023 Apr 03.
Article in English | MEDLINE | ID: mdl-36460614

ABSTRACT

Quantum chemistry calculations predict that besides the reported single metal anion Pt- , Ni- can also mediate the co-conversion of CO2 and CH4 to form [CH3 -M(CO2 )-H]- complex, followed by transformation to C-C coupling product [H3 CCOO-M-H]- (A), hydrogenation products [H3 C-M-OCOH]- (B) and [H3 C-M-COOH]- . For Pd- , a fourth product channel leading to PdCO2 - …CH4 becomes more competitive. For Ni- , the feed order must be CO2 first, as the weaker donor-acceptor interaction between Ni- and CH4 increases the C-H activation barrier, which is reduced by [Ni-CO2 ]- . For Ni- /Pt- , the highly exothermic products A and B are similarly stable with submerged barrier that favors B. The smaller barrier difference between A and B for Ni- suggests the C-C coupling product is more competitive in the presence of Ni- than Pt- . The charge redistribution from M- is the driving force for product B channel. This study adds our understanding of single atomic anions to activate CH4 and CO2 simultaneously.

9.
Int Microbiol ; 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38062211

ABSTRACT

Aeromonas salmonicida is the typical pathogen causing furunculosis, reported widely in salmonids. Because of multiple serotypes, the control of A. salmonicida-caused disease has increasingly received much attention. Recently, A. salmonicida infection was reported in non-salmonid fish species. Here, a pathogenic A. salmonicida, named as As-s, was isolated from cultured snakehead (Channa argus) in a local fish farm in Shandong, China. As-s displayed clear hemolysis, amylase, and positive catalase activities, and grew at a wide range of temperatures (10-37 °C) and pH values (5.5-8.5). As-s was highly sensitive to cefuroxime sodium, ceftriaxone, ceftazidime, piperacillin, and cefoperazone and also apparently sensitive to chloramphenicol, erythromycin, and 25% cinnamaldehyde. The Virulence array protein gene cloning' results suggested that As-s has this gene compared with the other two vapA-containing strains, despite a close relationship of these strains via phylogenetic analysis. Severe ulcers on skin, muscle, and abnormal liver, and hemorrhage in pectoral/ventral fins and anal region were observed, and exophthalmos were also noticed in infected juvenile snakehead, as well as necrosis and infiltration of blood cells emerged in the internal organs using pathological section. In addition, As-s caused high mortality in snakehead, consistently with its immune gene response. This study reports the first isolation of vapA-absent A. salmonicida in snakehead.

10.
Inorg Chem ; 62(15): 6102-6108, 2023 Apr 17.
Article in English | MEDLINE | ID: mdl-37021782

ABSTRACT

The direct coupling of dinitrogen (N2) and oxygen (O2) to produce value-added chemicals such as nitric acid (HNO3) at room temperature is fascinating but quite challenging because of the inertness of N2 molecules. Herein, an interesting reaction pathway is proposed for a direct conversion of N2 and O2 mediated by all-metal Y3+ cations. This reaction pattern begins with the N≡N triple bond cleavage by Y3+ to generate a dinitride cation Y2N2+, and the electrons that lead to N2 activation in this process mainly originate from Y atoms. In the following consecutive reactions with two O2 molecules, the electrons stored in the N atoms are gradually released to reduce O2 through re-formation and re-fracture of the N-N bonds, with concomitant release of two NO molecules. Therefore, the reversible N-N bond switching acts as an efficient electron reservoir to drive the oxidation of the reduced N atoms, leading to the formation of NO molecules. This method of producing NO by direct coupling N2 and O2 molecules, which is the reversible N-N bond switching, may provide a new strategy for the direct synthesis of HNO3, etc.

11.
Int J Mol Sci ; 24(20)2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37895148

ABSTRACT

COVID-19 pandemic has caused widespread panic and fear among the global population. As such, repurposing drugs are being used as viable therapeutic options due to the limited effective treatments for Long COVID symptoms. Ivermectin is one of the emerging repurposed drugs that has been shown effective to have antiviral effects in clinical trials. In addition, antioxidant compounds are also gaining attention due to their capabilities of reducing inflammation and severity of symptoms. Due to the absence of knowledge in pharmacogenomics and modes of actions in the human body for these compounds, this study aims to provide a pharmacogenomic profile for the combination of ivermectin and six selected antioxidants (epigallocatechin gallate (EGCG), curcumin, sesamin, anthocyanins, quercetin, and N-acetylcysteine (NAC)) as potentially effective regimens for long COVID symptoms. Results showed that there were 12 interacting genes found among the ivermectin, 6 antioxidants, and COVID-19. For network pharmacology, the 12 common interacting genes/proteins had the highest associations with Pertussis pathway, AGE-RAGE signaling pathway in diabetic complications, and colorectal cancer in the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Disease analyses also revealed that the top three relevant diseases with COVID-19 infections were diabetes mellitus, ischemia, reperfusion injury. We also identified 6 potential target microRNAs (miRNAs) of the 12 commonly curated genes used as molecular biomarkers for COVID-19 treatments. The established pharmacogenomic network, disease analyses, and identified miRNAs could facilitate developments of effective regimens for chronic sequelae of COVID-19 especially in this post-pandemic era. However, further studies and clinical trials are needed to substantiate the effectiveness and dosages for COVID-19 treatments.


Subject(s)
COVID-19 , MicroRNAs , Humans , COVID-19/genetics , Antioxidants/therapeutic use , Post-Acute COVID-19 Syndrome , Ivermectin/therapeutic use , Pandemics , Anthocyanins , Pharmacogenetics , MicroRNAs/genetics
12.
J Fish Dis ; 45(8): 1117-1132, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35514291

ABSTRACT

Probiotics have been used to alleviate disease transmission in aquaculture. However, there are limited studies on probiotic use in modulating tilapia lake virus (TiLV). We assessed commercially available probiotic supplements used in TiLV-infected tilapia and performed mortality and cohabitation assays. We developed a mechanistic approach to predict dose-response interactions of probiotic effects on mortality and immune gene response. We used a susceptible-infected-mortality disease model to assess key epidemiological parameters such as transmission rate and basic reproduction number (R0 ) based on our viral load dynamic data. We found that the most marked benefits of probiotics are significantly associated with immune system enhancements (~30%) and reductions in disease transmission (~80%) and R0 (~70%) in tilapia populations, resulting in a higher tolerance of farming densities (~400 fold) in aquaculture. These findings provide early insights as to how probiotic use-related factors may influence TiLV transmission and the immune responses in TiLV-infected tilapia. Our study facilitates understanding the mode of action of probiotics in disease containment and predicting better probiotic dosages in diet and supplements to achieve the optimal culturing conditions. Overall, our analysis assures that further study of rationally designed and targeted probiotics, or mechanistic modelling is warranted on the basis of promising early data of this approach.


Subject(s)
Fish Diseases , Probiotics , Tilapia , Animals , Aquaculture , Immunity , Probiotics/pharmacology
13.
Sensors (Basel) ; 22(6)2022 Mar 21.
Article in English | MEDLINE | ID: mdl-35336588

ABSTRACT

Containers and microservices have become the most popular method for hosting IoT applications in cloud servers. However, one major security issue of this method is that if a container image contains software with security vulnerabilities, the associated microservices also become vulnerable at run-time. Existing works attempted to reduce this risk with vulnerability-scanning tools. They, however, demand an up-to-date database and may not work with unpublished vulnerabilities. In this paper, we propose a novel system to strengthen container security from unknown attack using the mimic defense framework. Specifically, we constructed a resource pool with variant images and observe the inconsistency in execution results, from which we can identify potential vulnerabilities. To avoid continuous attack, we created a graph-based scheduling strategy to maximize the randomness and heterogeneity of the images used to replace the current images. We implemented a prototype using Kubernetes. Experimental results show that our framework makes hackers have to send 54.9% more random requests to complete the attack and increases the defence success rate by around 8.16% over the baseline framework to avoid the continuous unknown attacks.


Subject(s)
Data Management , Software , Defense Mechanisms
14.
Int J Mol Sci ; 23(23)2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36499711

ABSTRACT

Symptom treatments for Coronavirus disease 2019 (COVID-19) infection and Long COVID are one of the most critical issues of the pandemic era. In light of the lack of standardized medications for treating COVID-19 symptoms, traditional Chinese medicine (TCM) has emerged as a potentially viable strategy based on numerous studies and clinical manifestations. Taiwan Chingguan Yihau (NRICM101), a TCM designed based on a medicinal formula with a long history of almost 500 years, has demonstrated its antiviral properties through clinical studies, yet the pharmacogenomic knowledge for this formula remains unclear. The molecular mechanism of NRICM101 was systematically analyzed by using exploratory bioinformatics and pharmacodynamics (PD) approaches. Results showed that there were 434 common interactions found between NRICM101 and COVID-19 related genes/proteins. For the network pharmacology of the NRICM101, the 434 common interacting genes/proteins had the highest associations with the interleukin (IL)-17 signaling pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Moreover, the tumor necrosis factor (TNF) was found to have the highest association with the 30 most frequently curated NRICM101 chemicals. Disease analyses also revealed that the most relevant diseases with COVID-19 infections were pathology, followed by cancer, digestive system disease, and cardiovascular disease. The 30 most frequently curated human genes and 2 microRNAs identified in this study could also be used as molecular biomarkers or therapeutic options for COVID-19 treatments. In addition, dose-response profiles of NRICM101 doses and IL-6 or TNF-α expressions in cell cultures of murine alveolar macrophages were constructed to provide pharmacodynamic (PD) information of NRICM101. The prevalent use of NRICM101 for standardized treatments to attenuate common residual syndromes or chronic sequelae of COVID-19 were also revealed for post-pandemic future.


Subject(s)
COVID-19 , Drugs, Chinese Herbal , Humans , Animals , Mice , Post-Acute COVID-19 Syndrome , COVID-19 Drug Treatment , Network Pharmacology , Medicine, Chinese Traditional , Tumor Necrosis Factor-alpha , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Molecular Docking Simulation
15.
Molecules ; 27(22)2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36432170

ABSTRACT

Halogen bonds (XBs) between metal anions and halides have seldom been reported because metal anions are reactive for XB donors. The pyramidal-shaped Mn(CO)5- anion is a candidate metallic XB acceptor with a ligand-protected metal core that maintains the negative charge and an open site to accept XB donors. Herein, Mn(CO)5- is prepared by electrospray ionization, and its reaction with CH3I in gas phase is studied using mass spectrometry and density functional theory (DFT) calculation. The product observed experimentally at m/z = 337 is assigned as [IMn(CO)4(OCCH3)]-, which is formed by successive nucleophilic substitution and reductive elimination, instead of the halogen-bonded complex (XC) CH3-I···Mn(CO)5-, because the I···Mn interaction is weak within XC and it could be a transient species. Inspiringly, DFT calculations predict that replacing CH3I with CF3I can strengthen the halogen bonding within the XC due to the electro-withdrawing ability of F. More importantly, in so doing, the nucleophilic substitution barrier can be raised significantly, ~30 kcal/mol, thus leaving the system trapping within the XC region. In brief, the combination of a passivating metal core and the introduction of an electro-withdrawing group to the halide can enable strong halogen bonding between metallic anion and iodide.

16.
Molecules ; 27(1)2022 Jan 04.
Article in English | MEDLINE | ID: mdl-35011542

ABSTRACT

We characterized the stationary points along the nucleophilic substitution (SN2), oxidative insertion (OI), halogen abstraction (XA), and proton transfer (PT) product channels of M- + CH3X (M = Cu, Ag, Au; X = F, Cl, Br, I) reactions using the CCSD(T)/aug-cc-pVTZ level of theory. In general, the reaction energies follow the order of PT > XA > SN2 > OI. The OI channel that results in oxidative insertion complex [CH3-M-X]- is most exothermic, and can be formed through a front-side attack of M on the C-X bond via a high transition state OxTS or through a SN2-mediated halogen rearrangement path via a much lower transition state invTS. The order of OxTS > invTS is inverted when changing M- to Pd, a d10 metal, because the symmetry of their HOMO orbital is different. The back-side attack SN2 pathway proceeds via typical Walden-inversion transition state that connects to pre- and post-reaction complexes. For X = Cl/Br/I, the invSN2-TS's are, in general, submerged. The shape of this M- + CH3X SN2 PES is flatter as compared to that of a main-group base like F- + CH3X, whose PES has a double-well shape. When X = Br/I, a linear halogen-bonded complex [CH3-X∙··M]- can be formed as an intermediate upon the front-side attachment of M on the halogen atom X, and it either dissociates to CH3 + MX- through halogen abstraction or bends the C-X-M angle to continue the back-side SN2 path. Natural bond orbital analysis shows a polar covalent M-X bond is formed within oxidative insertion complex [CH3-M-X]-, whereas a noncovalent M-X halogen-bond interaction exists for the [CH3-X∙··M]- complex. This work explores competing channels of the M- + CH3X reaction in the gas phase and the potential energy surface is useful in understanding the dynamic behavior of the title and analogous reactions.

17.
Mol Biol Evol ; 37(5): 1452-1461, 2020 05 01.
Article in English | MEDLINE | ID: mdl-31904835

ABSTRACT

Control of gene expression has been found to be predominantly determined at the level of protein translation. However, to date, reduced expression from duplicated genes in eukaryotes for dosage maintenance has only been linked to transcriptional control involving epigenetic mechanisms. Here, we hypothesize that dosage maintenance following gene duplication also involves regulation at the protein level. To test this hypothesis, we compared transcriptome and proteome data of yeast models, Saccharomyces cerevisiae and Schizosaccharomyces pombe, and worm models, Caenorhabditis elegans and Caenorhabditis briggsae, to investigate lineage-specifically duplicated genes. Duplicated genes in both eukaryotic models exhibited a reduced protein-to-mRNA abundance ratio. Moreover, dosage sensitive genes, represented by genes encoding protein complex subunits, reduced their protein-to-mRNA abundance ratios more significantly than the other genes after duplication events. An analysis of ribosome profiling (Ribo-Seq) data further showed that reduced translational efficiency was more prominent for dosage sensitive genes than for the other genes. Meanwhile, no difference in protein degradation rate was associated with duplication events. Translationally repressed duplicated genes were also more likely to be inhibited at the level of transcription. Taken together, these results suggest that translation-mediated dosage control is partially contributed by natural selection and it enhances transcriptional control in maintaining gene dosage after gene duplication events during eukaryotic genome evolution.


Subject(s)
Gene Duplication , Protein Biosynthesis , Animals , Biological Evolution , Caenorhabditis elegans , Proteome , Saccharomyces cerevisiae , Schizosaccharomyces , Transcriptome
18.
Bioorg Med Chem ; 35: 116090, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33639594

ABSTRACT

Manganese(III) porphyrins (MnIIIPs) as MRI contrast agents (CAs) have drawn particular attention due to their high longitudinal relaxivity (r1) and unique biodistribution. In this work, two MnIIIP-based oligomers, MnPD and MnPT, were designed to further improve the relaxivity with ease of synthesis. The two compounds were fully characterized and their nuclear magnetic relaxation dispersion (NMRD) profiles were acquired with a fast field cycling NMR relaxometer. Both of the compounds exhibited extended high molar r1 at high fields, higher than that of Gd-DTPA, the first clinical gadolinium(III)-based MRI CA. The r1 value of per manganese atom increased with the increasing number of MnIIIP building blocks, suggesting rotational correlation time (τR) played dominant role in the r1 dispersion. The toxicity of the two MnIIIPs and the imaging effectiveness were estimated in vitro and in vivo. With good biocompatibility, significant contrast enhancement, and complete excretion in 24 h, MnPD and MnPT are both promising for high field clinical applications. The applied strategy also potentially provided a facile approach for creation of more MnIIIP oligomer as efficient T1 MRI CAs.


Subject(s)
Contrast Media/chemistry , Magnetic Resonance Imaging , Metalloporphyrins/chemistry , Animals , Cell Line , Cell Survival/drug effects , Contrast Media/pharmacology , Dose-Response Relationship, Drug , Humans , Male , Metalloporphyrins/pharmacology , Mice , Mice, Inbred ICR , Molecular Structure
19.
Acta Pharmacol Sin ; 42(12): 2155-2172, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33931765

ABSTRACT

LianhuaQingwen capsule, prepared from an herbal combination, is officially recommended as treatment for COVID-19 in China. Of the serial pharmacokinetic investigations we designed to facilitate identifying LianhuaQingwen compounds that are likely to be therapeutically important, the current investigation focused on the component Glycyrrhiza uralensis roots (Gancao). Besides its function in COVID-19 treatment, Gancao is able to induce pseudoaldosteronism by inhibiting renal 11ß-HSD2. Systemic and colon-luminal exposure to Gancao compounds were characterized in volunteers receiving LianhuaQingwen and by in vitro metabolism studies. Access of Gancao compounds to 11ß-HSD2 was characterized using human/rat, in vitro transport, and plasma protein binding studies, while 11ß-HSD2 inhibition was assessed using human kidney microsomes. LianhuaQingwen contained a total of 41 Gancao constituents (0.01-8.56 µmol/day). Although glycyrrhizin (1), licorice saponin G2 (2), and liquiritin/liquiritin apioside (21/22) were the major Gancao constituents in LianhuaQingwen, their poor intestinal absorption and access to colonic microbiota resulted in significant levels of their respective deglycosylated metabolites glycyrrhetic acid (8), 24-hydroxyglycyrrhetic acid (M2D; a new Gancao metabolite), and liquiritigenin (27) in human plasma and feces after dosing. These circulating metabolites were glucuronized/sulfated in the liver and then excreted into bile. Hepatic oxidation of 8 also yielded M2D. Circulating 8 and M2D, having good membrane permeability, could access (via passive tubular reabsorption) and inhibit renal 11ß-HSD2. Collectively, 1 and 2 were metabolically activated to the pseudoaldosterogenic compounds 8 and M2D. This investigation, together with such investigations of other components, has implications for precisely defining therapeutic benefit of LianhuaQingwen and conditions for its safe use.


Subject(s)
Antiviral Agents/pharmacokinetics , COVID-19 Drug Treatment , Drugs, Chinese Herbal/pharmacokinetics , Phytochemicals/pharmacokinetics , 11-beta-Hydroxysteroid Dehydrogenase Type 2/antagonists & inhibitors , 11-beta-Hydroxysteroid Dehydrogenase Type 2/metabolism , Administration, Oral , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Biological Availability , Biotransformation , Capsules , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/adverse effects , Female , Glycyrrhiza/adverse effects , HEK293 Cells , Humans , Liddle Syndrome/chemically induced , Liddle Syndrome/enzymology , Male , Patient Safety , Phytochemicals/administration & dosage , Phytochemicals/adverse effects , Rats, Sprague-Dawley , Risk Assessment
20.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4244-4251, 2021 Aug.
Article in Zh | MEDLINE | ID: mdl-34467739

ABSTRACT

Coumarins are the main active components in Psoraleae Fructus. To study the multi-component pharmacokinetics of Psoraleae Fructus, this study established a sensitive and rapid ultra-pressure liquid chromatography coupled to tandem mass spectrometry(UPLC-MS/MS) method for simultaneous determination of psoralen, isopsoralen, psoralenoside, and isopsoralenoside in rat plasma. After validation, the method was applied to the investigation of pharmacokinetics of psoralen, isopsoralen, psoralenoside, and isopso-ralenoside in rats after single and multiple administration of Psoraleae Fructus extract. The results revealed that the exposure of psoralen and isopsoralen in rat plasma was high after a single intragastric administration of Psoraleae Fructus extract, with an AUC_(0-∞) of 443 619-582 680 and 167 314-276 903 ng·mL~(-1)·h~(-1), respectively. Compared with these two compounds, the exposure of psoralenoside and isopsoralenoside was lower with marked gender difference. After 7-day administration of Psoraleae Fructus extract to rats, the AUC_(0-∞) of psoralen and isopsoralen was 29 701-81 783 and 39 234-89 914 ng·mL~(-1)·h~(-1), respectively, which was significantly lower than that at the first day(P<0.05), and that of psoralenoside and isopsoralenoside was 7 360-19 342 and 8 823-45 501 ng·mL~(-1)·h~(-1), respectively. There was no significant gender difference in exposure of psoralenoside and isopsoralenoside in male and female rats. However, the exposure of psoralenoside and isopsoralenoside in male rats was reduced(P<0.05), and the t_(1/2) and mean residence time(MRT) were shortened, suggesting that the removal of these two compounds from the body was accelerated.


Subject(s)
Drugs, Chinese Herbal , Furocoumarins , Psoralea , Administration, Oral , Animals , Benzofurans , Chromatography, High Pressure Liquid , Chromatography, Liquid , Ficusin , Furocoumarins/analysis , Glycosides , Rats , Tandem Mass Spectrometry
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