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1.
Inorg Chem ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38646875

RESUMO

Herein, a new centrosymmetric phase Na4Nb8P4O32 (referred to as CS-Na4Nb8P4O32) was obtained by a molten salt method, which is a polymorph of niobium phosphate bronze Na4Nb8P4O32. CS-Na4Nb8P4O32 displays high structural similarity to the noncentrosymmetric Na4Nb8P4O32 phase (referred to as NCS-Na4Nb8P4O32): Distorted NbO6 octahedra are corner-coordinated to form ReO3-type layers, which are further joined together by isolated PO4 tetrahedra. However, two polymorphous phases adopt different packings of structural units, resulting in distinct symmetries. NbO3 layers and PO4 tetrahedra are reversely arranged along the crystallographic a direction in CS-Na4Nb8P4O32, thereby producing a centrosymmetric structure. The reverse packing cancels out all contributions of dipole moments originating from the distorted NbO6 octahedra; NCS-Na4Nb8P4O32 exhibits the C2-rotation distribution of NbO3 layers and PO4 tetrahedra, thus generating a noncentrosymmetric and polar structure. The C2-rotation packing of structural units brings a constructive addition of the dipole moments, further obtaining large calculated independent second harmonic generation susceptibilities. The study of structural evolution deduced by the packings of structural units in polymorphous Na4Nb8P4O32 might provide valuable insights into polymorphism and structural regulation.

2.
Rheumatology (Oxford) ; 63(3): 826-836, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37326830

RESUMO

OBJECTIVE: Sialylation of the crystallizable fragment (Fc) of ACPAs, which is catalysed by ß-galactoside α-2,6-sialyltransferase 1 (ST6GAL1) could attenuate inflammation of RA. In this study, we screened the transcription factor of ST6GAL1 and elucidated the mechanism of transcriptionally upregulating sialylation of ACPAs in B cells to explore its role in the progression of RA. METHODS: Transcription factors interacting with the P2 promoter of ST6GAL1 were screened by DNA pull-down and liquid chromatography with tandem mass spectrometry (LC-MS/MS), and verified by chromatin immunoprecipitation (ChIP), dual luciferase reporter assay and electrophoretic mobility shift assay (EMSA). The function of the CCCTC-binding factor (CTCF) on the expression of ST6GAL1 and the inflammatory effect of ACPAs were verified by knocking down and overexpressing CTCF in B cells. The CIA model was constructed from B cell-specific CTCF knockout mice to explore the effect of CTCF on arthritis progression. RESULTS: We observed that the levels of ST6GAL1 and ACPAs sialylation decreased in the serum of RA patients and were negatively correlated with DAS28 scores. Subsequently, CTCF was screened and verified as the transcription factor interacting with the P2 promoter of ST6GAL1, which enhances the sialylation of ACPAs, thus weakening the inflammatory activity of ACPAs. Furthermore, the above results were also verified in the CIA model constructed from B cell-specific CTCF knockout mice. CONCLUSION: CCCTC-binding factor is the specific transcription factor of ß-galactoside α-2,6-sialyltransferase 1 in B cells that upregulates the sialylation of ACPAs in RA and attenuates the disease progression.


Assuntos
Ácidos Aminossalicílicos , Artrite Reumatoide , Galactosídeos , Fatores de Transcrição , Animais , Camundongos , Humanos , Fator de Ligação a CCCTC , Anticorpos Antiproteína Citrulinada , Cromatografia Líquida , Espectrometria de Massas em Tandem , Camundongos Knockout , Sialiltransferases/genética
3.
Exp Anim ; 73(1): 20-28, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37460311

RESUMO

Nonhuman primates are important research models for basic vision research, preclinical pathogenesis, and treatment studies due to strong similarities in retinal structure and function with humans. We compared retinal parameters between 10 healthy normal rhesus macaques (Macaca mulatta) and 10 cynomolgus macaques (Macaca fascicularis) by optical coherence tomography and electroretinography. The Heidelberg Spectralis® HRA+OCT and Roland multifocal electrophysiometer were used to analyze retinal morphology, multifocal electroretinograms (mfERGs), and full-field electroretinograms (ff-ERGs). Mean retinal thickness was lowest in the central fovea of macaques and did not differ significantly between species, but the retinal thicknesses of the nerve fiber ganglion cell layer and the inner plexiform layer were significantly different. The amplitude density of the N1 wave was lower in rhesus macaques than in cynomolgus macaques in ring and quadrant areas. Dark-adapted 3.0 oscillatory potentials (reflection of amacrine cell activity) and light-adapted 30-hz flicker ERG (a sensitive cone-pathway-driven response) waveforms of the ff-ERG were similar in both species, while the times to peaks in dark-adapted 0.01 ERG (the rod-driven response of bipolar cells) and dark-adapted 3.0 ERG (combined rod and cone system responses) as well as the implicit times of the a- and b-waves in light-adapted 3.0 ERG (the single-flash cone response) were substantially different. This study provides normative retinal parameters for nonhuman primate research on basic and clinical ophthalmology, as well as a reference for researchers in the appropriate selection of rhesus or cynomolgus macaques as models for ophthalmology studies.


Assuntos
Eletrorretinografia , Retina , Humanos , Animais , Macaca mulatta , Macaca fascicularis , Retina/fisiologia , Eletrorretinografia/métodos , Neurônios
4.
Biomed Pharmacother ; 168: 115666, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832409

RESUMO

Rheumatoid arthritis (RA) is the most common chronic autoimmune disease worldwide. Although progress has been made in RA treatment in recent decades, remission cannot be effectively achieved for a considerable proportion of RA patients. Thus, novel potential targets for therapeutic strategies are needed. Semaphorin 5A (SEMA5A) plays a pivotal role in RA progression by facilitating pannus formation, and it is a promising therapeutic target. In this study, we sought to develop an antibody treatment strategy targeting SEMA5A and evaluate its therapeutic effect using a collagen-induced arthritis (CIA) model. We generated SYD12-12, a fully human SEMA5A blocking antibody, through phage display technology. SYD12-12 intervention effectively inhibited angiogenesis and aggressive phenotypes of RA synoviocytes in vitro and dose-dependently inhibited synovial hyperplasia, pannus formation, bone destruction in CIA mice. Notably, SYD12-12 also improved the Treg/Th17 imbalance in CIA mice. We confirmed through immunofluorescence and molecular docking that SYD12-12 integrated with the unique TSP-1 domain of SEMA5A. In conclusion, we developed and characterized a fully human SEMA5A-blocking antibody for the first time. SYD12-12 effectively alleviated disease progression in CIA mice by inhibiting pannus formation and improving the Treg/Th17 imbalance, demonstrating its potential for the RA treatment.


Assuntos
Artrite Experimental , Artrite Reumatoide , Semaforinas , Sinoviócitos , Animais , Humanos , Camundongos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico , Simulação de Acoplamento Molecular
5.
PeerJ ; 11: e15322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187516

RESUMO

Background: Elaeocarpaceae is a vital family in tropical and subtropical forests. Compared with the important position of Elaeocarpaceae species in forest ecosystem and the concern of medicinal value, the most research on Elaeocarpaceae are classification and taxonomy. Molecular systematics has corrected the morphological misjudgment, and it belongs to Oxalidales. Phylogenetic and divergence time estimates of Elaeocarpaceae is mostly constructed by using chloroplast gene fragments. At present, although there are reports on the chloroplast structure of Elaeocarpaceae, a comprehensive analysis of the chloroplast structure of Elaeocarpaceae is lacking. Methods: To understand the variation in chloroplast sequence size and structure in Elaeocarpaceae, the chloroplast genomes of nine species were sequenced using the Illumina HiSeq 2500 platform and further assembled and annotated with Elaeocarpus japonicus and Sloanea sinensis (family Elaeocarpaceae) as references. A phylogenomic tree was constructed based on the complete chloroplast genomes of the 11 species representing five genera of Elaeocarpaceae. Chloroplast genome characteristics were examined by using Circoletto and IRscope software. Results: The results revealed the following: (a) The 11 sequenced chloroplast genomes ranged in size from 157,546 to 159,400 bp. (b) The chloroplast genomes of Elaeocarpus, Sloanea, Crinodendron and Vallea lacked the rpl32 gene in the small single-copy (SSC) region. The large single-copy (LSC) region of the chloroplast genomes lacked the ndhK gene in Elaeocarpus, Vallea stipularis, and Aristotelia fruticosa. The LSC region of the chloroplast genomes lacked the infA gene in genus Elaeocarpus and Crinodendron patagua. (c) Through inverted repeat (IR) expansion and contraction analysis, a significant difference was found between the LSC/IRB and IRA/LSC boundaries among these species. Rps3 was detected in the neighboring regions of the LSC and IRb regions in Elaeocarpus. (d) Phylogenomic analysis revealed that the genus Elaeocarpus is closely related to Crinodendron patagua on an independent branch and Aristotelia fruticosa is closely related to Vallea stipularis, forming a clade with the genus Sloanea. Structural comparisons showed that Elaeocarpaceae diverged at 60 Mya, the genus Elaeocarpus diverged 53 Mya and that the genus Sloanea diverged 0.44 Mya. These results provide new insight into the evolution of the Elaeocarpaceae.


Assuntos
Elaeocarpaceae , Genoma de Cloroplastos , Filogenia , Genoma de Cloroplastos/genética , Elaeocarpaceae/genética , Ecossistema , Cloroplastos/genética
6.
Sensors (Basel) ; 23(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36904640

RESUMO

In the process of manufacture and transportation, vials are prone to breakage and cracks. Oxygen (O2) in the air entering vials can lead to the deterioration of medicine and a reduction in pesticide effects, threatening the life of patients. Therefore, accurate measurement of the headspace O2 concentration for vials is crucial to ensure pharmaceutical quality. In this invited paper, a novel headspace oxygen concentration measurement (HOCM) sensor for vials was developed based on tunable diode laser absorption spectroscopy (TDLAS). First, a long-optical-path multi-pass cell was designed by optimizing the original system. Moreover, vials with different O2 concentrations (0%, 5%, 10%, 15%, 20%, and 25%) were measured with this optimized system in order to study the relationship between the leakage coefficient and O2 concentration; the root mean square error of the fitting was 0.13. Moreover, the measurement accuracy indicates that the novel HOCM sensor achieved an average percentage error of 1.9%. Sealed vials with different leakage holes (4, 6, 8, and 10 mm) were prepared to investigate the variation in the headspace O2 concentration with time. The results show that the novel HOCM sensor is non-invasive and has a fast response and high accuracy, with prospects in applications for online quality supervision and management of production lines.

7.
BMC Biotechnol ; 23(1): 6, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869335

RESUMO

BACKGROUND: Connective tissue growth factor (CTGF) plays a pivotal role in the pathogenesis of rheumatoid arthritis (RA) by facilitating angiogenesis and is a promising therapeutic target for RA treatment. Herein, we generated a fully human CTGF blocking monoclonal antibody (mAb) through phage display technology. RESULTS: A single-chain fragment variable (scFv) with a high affinity to human CTGF was isolated through screening a fully human phage display library. We carried out affinity maturation to elevate its affinity for CTGF and reconstructed it into a full-length IgG1 format for further optimization. Surface plasmon resonance (SPR) data showed that full-length antibody IgG mut-B2 bound to CTGF with a dissociation constant (KD) as low as 0.782 nM. In the collagen-induced arthritis (CIA) mice, IgG mut-B2 alleviated arthritis and decreased the level of pro-inflammatory cytokines in a dose-dependent manner. Furthermore, we confirmed that the TSP-1 domain of CTGF is essential for the interaction. Additionally, the results of Transwell assays, tube formation experiments, and chorioallantoic membrane (CAM) assays showed that IgG mut-B2 could effectively inhibit angiogenesis. CONCLUSION: The fully human mAb that antagonizes CTGF could effectively alleviate arthritis in CIA mice, and its mechanism is tightly associated with the TSP-1 domain of CTGF.


Assuntos
Artrite Experimental , Artrite Reumatoide , Humanos , Animais , Camundongos , Fator de Crescimento do Tecido Conjuntivo , Trombospondina 1 , Anticorpos Monoclonais , Imunoglobulina G
8.
Front Public Health ; 10: 942377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968424

RESUMO

Objective: The objective of this study was to assess the status and trends of antiviral treatment in outpatients with herpes zoster in China. Methods: Prescription data on antiviral drugs were extracted from the database of the Hospital Prescription Analysis Program of China according to the inclusion criteria. Yearly prescriptions and costs were calculated, and trends were analyzed. The trends were further stratified by age, sex, and specific drug use. The distribution of defined daily costs (DDCs) of valaciclovir and famciclovir were analyzed, and trends in the median DDCs were identified. Results: A total of 132,911 prescriptions from 49 hospitals located in six major areas of China were included in the analysis. The yearly prescriptions containing antivirals increased from 8,819 in 2010 to 16,361 in 2019. The percentage of prescriptions for patients aged 65 years and above also increased (27.7% in 2010 to 31.0% in 2019), and the number of prescriptions for females was higher than those for males (P < 0.001). The average cost of antivirals per prescription decreased; thus, the yearly cost showed no increasing trend. The main prescribed antivirals were valaciclovir and famciclovir, which progressively increased in prescriptions. The use of acyclovir decreased during the study period. Prescriptions containing topical formulations, acyclovir and penciclovir, both increased. The DDCs of valaciclovir and famciclovir decreased dramatically. Conclusion: The use of antivirals has increased over the decade, while the cost has not. Antiviral treatments adhere well to recent recommendations, except for the use of topical antivirals. The findings of this study may benefit the healthcare source allocation and management of herpes zoster in China.


Assuntos
Antivirais , Herpes Zoster , Aciclovir/efeitos adversos , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , China , Famciclovir/uso terapêutico , Feminino , Herpes Zoster/induzido quimicamente , Herpes Zoster/tratamento farmacológico , Herpes Zoster/epidemiologia , Humanos , Masculino , Pacientes Ambulatoriais , Valaciclovir/uso terapêutico
9.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743157

RESUMO

Traumatic optic neuropathy (TON) is a significant cause of vision loss and irreversible blindness worldwide. It is defined as retinal ganglion cell death and axon degeneration caused by injury. Optic nerve crush (ONC), a well-validated model of TON, activates retinal microglia and initiates neuroinflammation. High-mobility group box 1 (HMGB1), a non-histone chromosomal binding protein in the nucleus of eukaryotic cells, is an important inducer of microglial activation and pro-inflammatory cytokine release. The purpose of this study was to examine the protective effects and mechanism of the HMGB1 inhibitor BoxA to neuroinflammation-induced retinal ganglion cells (RGCs) damage in traumatic optic neuropathy. For that purpose, an optic nerve crush model was established in C57BL/6J mice at 10-12 weeks. Model mice received an intravitreal injection of PBS and the HMGB1 inhibitor BoxA. Our data demonstrated that HMGB1 expression increased after optic nerve crush. Retinal ganglion cell function and morphology were damaged, and retinal ganglion cell numbers were reduced after optic nerve crush. Intravitreal injection of BoxA after ONC can alleviate damage. Furthermore, BoxA reduced microglial activation and expression levels of nuclear factor κB (NF-kB), nucleotide-binding domain, leucine-rich repeat containing protein 3 (NLRP3), and apoptosis-associated speck-like protein containing a CARD (ASC) in experimental ONC mice. In summary, HMGB1 mediates NLRP3 inflammasome via NF-kB to participate in retinal inflammatory injury after ONC. Thus, intravitreal injection of BoxA has potential therapeutic benefits for the effective treatment of RGC death to prevent TON.


Assuntos
Proteína HMGB1 , Traumatismos do Nervo Óptico , Animais , Modelos Animais de Doenças , Proteína HMGB1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Compressão Nervosa , Doenças Neuroinflamatórias , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/metabolismo , Células Ganglionares da Retina/metabolismo
10.
Int J Infect Dis ; 120: 59-64, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35429639

RESUMO

OBJECTIVE: We conducted this multicenter retrospective study to evaluate the prevalence, clinical patterns, and risk factors for tigecycline-induced liver injury, which is a type of drug-induced liver injury (DILI). METHODS: Inpatients receiving intravenous tigecycline for ≥7 days were included. Patient information was collected to assess possible DILIs. The pattern and severity of tigecycline DILI were evaluated. A multivariable logistic regression model was used to identify the independent risk factors associated with tigecycline DILI. RESULTS: A total of 986 patients were identified and 397 patients were included in this study. The prevalence of tigecycline DILI was 10.3% (95% confidence interval [CI] = 7.51-13.7%). The most common type of tigecycline DILI was cholestatic, with mild severity observed in most cases. Abnormal baseline alanine aminotransferase levels (odds ratio [OR] = 3.11, 95% CI = 1.55-6.24, P = 0.001), intensive care unit admission (OR = 2.63, 95% CI = 1.32-5.36, P = 0.006), and treatment length (in weeks) (OR = 1.25, 95% CI = 1.05-1.49, P = 0.011) were independent risk factors for tigecycline DILI. CONCLUSION: Our results indicate that the prevalence of tigecycline DILI is high, and that the patients at risk should receive special attention.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Humanos , Prevalência , Estudos Retrospectivos , Fatores de Risco , Tigeciclina/efeitos adversos
11.
Artigo em Inglês | MEDLINE | ID: mdl-35139473

RESUMO

N-glycosylation is one of the major post-translational modifications, with significant effects on the mechanism of action, the efficacy, and the safety of antibody drugs or glycoproteins. With the growing application of therapeutic antibodies, routinely monitoring N-glycosylation becomes increasingly important during cell culture process development and quality control. However, the current pretreatment methods for N-glycan analysis are time- and labor-consuming. The purification procedure of enzymatically released glycans could also partly affect the accuracy of results due to its complexity. In this study, a rapid ultra-high performance liquid chromatography method based on magnetic bead extraction and 2-AB fluorescent labeling was developed and compared against three popular pretreatment methods for N-glycan profiling (two were solid phase extraction and the other was acetone precipitation). The method's repeatability results showed that magnetic bead extraction has higher precision (% relative standard deviation (RSD), 0.121.06%) than solid phase extraction (SPE) (%RSD, 0.38-8.02%) and acetone precipitation (%RSD, 0.42-8.58%). This robust pretreatment method also maximized the retention of some low abundance oligosaccharides, and may thus provide a rapid and high-throughput workflow option for N-Glycan analysis in the biopharmaceutical industry.


Assuntos
Anticorpos Monoclonais/química , Cromatografia Líquida de Alta Pressão/métodos , Polissacarídeos , Proteínas Recombinantes/química , Anticorpos Monoclonais/análise , Imãs , Polissacarídeos/análise , Polissacarídeos/química , Proteínas Recombinantes/análise , Proteínas Recombinantes/normas , Reprodutibilidade dos Testes , Extração em Fase Sólida
12.
Antibiotics (Basel) ; 10(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34438966

RESUMO

Topical anti-infectives are important in the management of ocular infections, but little is known about their current status and trends in their use in China. Thus, we carried out a prescription-based, cross-sectional study using the database of Hospital Prescription Analysis Projection of China, and aimed to analyze the trend in the use of ocular topical anti-infectives for outpatients of the ophthalmology department from 2013 to 2019. A total of 2,341,719 prescriptions from 61 hospitals located in six major areas written by ophthalmologists for outpatients were identified, and 1,002,254 of the prescriptions contained at least one anti-infective. The yearly anti-infective prescriptions increased continuously from 126,828 prescriptions in 2013 to 163,434 prescriptions in 2019. The cost also increased from 4,503,711 Chinese Yuan (CNY) in 2013 to CNY 5,860,945 in 2019. However, the use rate of anti-infectives decreased slightly from 46.5% in 2013 to 41.1% in 2019. Patients aged between 19 and 45 years old had the highest anti-infective use rate. Levofloxacin was the most frequently used anti-infective and kept on increasing among all age groups, occupying 67.1% of the total cost at the end of the study. Tobramycin was more frequently used in pediatric patients than in adults, but the use still decreased. Ganciclovir was the preferred anti-viral drug over acyclovir. In conclusion, the prescriptions and cost of ocular topical anti-infectives for outpatients both increased progressively. The increasingly widespread use of levofloxacin raised concerns regarding safety in pediatrics and resistance development. The observed trends can lead to the more efficient management of ocular anti-topical anti-infectives in China.

13.
Front Pharmacol ; 12: 690640, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447308

RESUMO

The prevalence of dry eye disease (DED) in old patients are high, corresponding to a substantial economic burden. In this cross-sectional study, we analyzed the trends in the topical prescriptional treatment of old patients with DED in six major areas of China. Information on topical drug prescriptions for DED patients aged above 60 years was extracted from the Hospital Prescription Analysis Cooperative Program of China database. Trends in yearly prescriptions and cost were analyzed. The data were further stratified by patient age and sex, drug class, and specific drug. A total of 130,734 prescriptions from 52 hospitals located in six major areas of China were analyzed. The number of prescripptions per year for patients with DED increased from 13,308 in 2013 to 22,074 in 2019, with a corresponding increase in cost of all topical drugs from 1,490,014 Chinese Yuan (CNY) to 2,618,206 CNY. Drugs for the treatment of DED accounted for the largest proportion of the total cost in each year. Ocular lubricants were the main pharmacotherapy agent. Sodium hyaluronate use increased over time, and the drug was used by 65.9% of patients by the end of the study. Pranoprofen was the second most frequently used drug. The most frequently used drugs for co-incident disease were antimicrobials. Treatment patterns for DED haven't changed, and the most frequently used drug combination was sodium hyaluronate and pranoprofen. In summary, prescription for old patients with DED and the cost of treatment are increasing. Ocular lubricants are the main treatment option, while sodium hyaluronate is the most frequently used drug. The observed trends can lead to more efficient allocation of health care resources in China.

14.
J Microbiol Methods ; 186: 106241, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33992679

RESUMO

Endotoxin is a kind of lipopolysaccharide that exits on the cell wall of Gram-negative bacteria. It can cause fever, shock or even death when is delivered into human body. So, it is necessary to control the endotoxin contamination for biopharmaceutical products that are mainly administered by intravenous route. Limulus Amebocyte Lysate (LAL)-based tests are usually used to detect endotoxin content in biologics formulations. However, an undesirable phenomenon called "Low Endotoxin Recovery (LER)" often occurs in formulation buffers that usually contain chelating component, such as sodium citrate, and amphiphilic surfactant, such as Tween-20. The occurrence of this LER phenomenon may interfere with endotoxin detection and cause false negative results. In this study, we compared the effect of different sample treatment methods on endotoxin detection and found that the LER phenomenon was better controlled under the conditions of low pH (pH = 5.0), low temperature (2-8 °C) and in the presence of divalent cations in the solution. In addition, although the endotoxin activity was found to have decreased due to LER phenomenon, the particle size distribution of endotoxin determined by dynamic light scattering (DLS) in LER solution did not change obviously, which is different from previous hypothesis about LER phenomenon in literature that the particle size of endotoxin aggregates would decrease under LER conditions. These findings provide some insights into different sample treatment methods for endotoxin detection and give a better understanding and solution on minimizing the LER phenomenon.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Endotoxinas/isolamento & purificação , Bactérias Gram-Negativas/química , Métodos Analíticos de Preparação de Amostras/instrumentação , Animais , Cátions Bivalentes/química , Endotoxinas/química , Endotoxinas/farmacologia , Caranguejos Ferradura , Concentração de Íons de Hidrogênio , Teste do Limulus , Lipopolissacarídeos/química , Lipopolissacarídeos/isolamento & purificação , Tamanho da Partícula , Tensoativos/química
15.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33893140

RESUMO

Venoms have evolved independently several times in Lepidoptera. Limacodidae is a family with worldwide distribution, many of which are venomous in the larval stage, but the composition and mode of action of their venom is unknown. Here, we use imaging technologies, transcriptomics, proteomics, and functional assays to provide a holistic picture of the venom system of a limacodid caterpillar, Doratifera vulnerans Contrary to dogma that defensive venoms are simple in composition, D. vulnerans produces a complex venom containing 151 proteinaceous toxins spanning 59 families, most of which are peptides <10 kDa. Three of the most abundant families of venom peptides (vulnericins) are 1) analogs of the adipokinetic hormone/corazonin-related neuropeptide, some of which are picomolar agonists of the endogenous insect receptor; 2) linear cationic peptides derived from cecropin, an insect innate immune peptide that kills bacteria and parasites by disrupting cell membranes; and 3) disulfide-rich knottins similar to those that dominate spider venoms. Using venom fractionation and a suite of synthetic venom peptides, we demonstrate that the cecropin-like peptides are responsible for the dominant pain effect observed in mammalian in vitro and in vivo nociception assays and therefore are likely to cause pain after natural envenomations by D. vulnerans Our data reveal convergent molecular evolution between limacodids, hymenopterans, and arachnids and demonstrate that lepidopteran venoms are an untapped source of novel bioactive peptides.


Assuntos
Venenos de Artrópodes/química , Proteínas de Insetos/química , Lepidópteros/química , Neuropeptídeos/química , Dor/genética , Animais , Venenos de Artrópodes/genética , Evolução Molecular , Proteínas de Insetos/genética , Mariposas/química , Neuropeptídeos/genética , Peptídeos/química , Peptídeos/genética , Proteômica , Venenos de Aranha/química , Venenos de Aranha/genética , Transcriptoma/genética
16.
Sci Rep ; 10(1): 10920, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616809

RESUMO

Alginate-degrading bacteria or alginate lyases can be used to oligomerize alginate. In this study, an alginate-degrading bacterium with high alginolytic activity was successfully screened by using Sargassum fusiforme sludge. When the strain was grown on a plate containing sodium alginate, the transparent ring diameter (D) was 2.2 cm and the ratio (D/d) of transparent ring diameter to colony diameter (d) was 8.8. After 36 h in culture at a temperature of 28 °C shaken at 150 r/min, the enzymatic activity of the fermentation supernatant reached 160 U/mL, and the enzymatic activity of the bacterial precipitate harvested was 2,645 U/mL. The strain was named Cobetia sp. cqz5-12. Its genome is circular in shape, 4,209,007 bp in size, with a 62.36% GC content. It contains 3,498 predicted coding genes, 72 tRNA genes, and 21 rRNA genes. The functional annotations for the coding genes demonstrated that there were 181 coding genes in the genome related to carbohydrate transport and metabolism and 699 coding genes with unknown functions. Three putative coding genes, alg2107, alg2108 and alg2112, related to alginate degradation were identified by analyzing the carbohydrate active enzyme (CAZy) database. Moreover, proteins Alg2107 and Alg2112 were successfully expressed and exhibited alginate lyase activity.


Assuntos
Genoma Bacteriano , Halomonadaceae/genética , Alginatos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Mapeamento Cromossômico , Cromossomos Bacterianos/genética , DNA Bacteriano/genética , DNA Circular/genética , Ontologia Genética , Halomonadaceae/enzimologia , Halomonadaceae/crescimento & desenvolvimento , Halomonadaceae/isolamento & purificação , Filogenia , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/isolamento & purificação , Sargassum/microbiologia , Sequenciamento Completo do Genoma
17.
Pharmacology ; 105(1-2): 79-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31587004

RESUMO

WZ35 is a monocarbonyl analog of curcumin, which had been proved advantage over curcumin in chemical stability and antitumor activity. However, its pharmacokinetic profile has not been determined. In the present study, an ultraperformance liquid chromatography-tandem mass spectrometry assay was developed to detect concentration of WZ35 in rat plasma. Subsequently, pharmacokinetic study showed that the oral bioavailability of WZ35 is 10.56%. Cytochrome P450 (CYP450) plays a major role in metabolizing exogenous substance. The concentration of WZ35 was sharply decreased while incubating with microsome. It's indicated that WZ35 is a substrate of CYP450s. Molecular docking assay showed that WZ35 can combine with CYP2B6 and CYP2C9 to form much more stable complex. The lowest docking energy was generated in complex with CYP2E1. The inhibition of CYP450s by WZ35 was also evaluated. Pan inhibitions of WZ35 on rat CYP3A2, CYP2B1, CYP2C11, CYP2D1, and -CYP2E1 were observed by detecting probe substrates (midazolam, bupropion, tolbutamide, dextromethorphan, chlorzoxazone) and metabolites accordingly. On an average, 80% activities of enzymes were blocked. Mechanistically, the inhibitions of WZ35 on CYP3A2, CYP2B1, CYP2E1 were in a time-dependent manner according to the results of IC50 shift assay. The collective data demonstrated that the oral bioavailability of monocarbonyl analog of curcumin has significantly improved compared to curcumin. It's both the substrate and inhibitor of CYP450s through in a time-dependent mechanism.


Assuntos
Antineoplásicos/farmacocinética , Curcumina/análogos & derivados , Curcumina/farmacocinética , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Animais , Antineoplásicos/sangue , Disponibilidade Biológica , Inibidores das Enzimas do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/metabolismo , Masculino , Simulação de Acoplamento Molecular , Ratos Sprague-Dawley
18.
Insect Biochem Mol Biol ; 118: 103310, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31870846

RESUMO

Many arthropod venom peptides have potential as bioinsecticides, drug leads, and pharmacological tools due to their specific neuromodulatory functions. Assassin flies (Asilidae) are a family of predaceous dipterans that produce a unique and complex peptide-rich venom for killing insect prey and deterring predators. However, very little is known about the structure and function of their venom peptides. We therefore used an E. coli periplasmic expression system to express four disulfide-rich peptides that we previously reported to exist in venom of the giant assassin fly Dolopus genitalis. After purification, each recombinant peptide eluted from a C18 column at a position closely matching its natural counterpart, strongly suggesting adoption of the native tertiary fold. Injection of purified recombinant peptides into blowflies (Lucilia cuprina) and crickets (Acheta domestica) revealed that two of the four recombinant peptides, named rDg3b and rDg12, inhibited escape behaviour in a manner that was rapid in onset (<1 min) and reversible. Homonuclear NMR solution structures revealed that rDg3b and rDg12 adopt cystine-stabilised α/ß defensin and inhibitor cystine knot folds, respectively. Although the closest known homologues of rDg3b at the level of primary structure are dipteran antimicrobial peptides such as sapecin and lucifensin, a DALI search showed that the tertiary structure of rDg3b most closely resembles the KV11.1-specific α-potassium channel toxin CnErg1 from venom of the scorpion Centruroides noxius. This is mainly due to the deletion of a large, unstructured loop between the first and second cysteine residues present in Dg3b homologues from non-asiloid, but not existing in asiloid, species. Patch-clamp electrophysiology experiments revealed that rDg3b shifts the voltage-dependence of KV11.1 channel activation to more depolarised potentials, but has no effect on KV1.3, KV2.1, KV10.1, KCa1.1, or the Drosophila Shaker channel. Although rDg12 shares the inhibitor cystine knot structure of many gating modifier toxins, rDg12 did not affect any of these KV channel subtypes. Our results demonstrate that multiple disulfide-rich peptide scaffolds have been convergently recruited into asilid and other animal venoms, and they provide insight into the molecular evolution accompanying their weaponisation.


Assuntos
Venenos de Artrópodes/genética , Miniproteínas Nó de Cistina/genética , Defensinas/genética , Dípteros/fisiologia , Proteínas de Insetos/genética , Sequência de Aminoácidos , Animais , Venenos de Artrópodes/metabolismo , Miniproteínas Nó de Cistina/metabolismo , Defensinas/metabolismo , Dípteros/genética , Proteínas de Insetos/metabolismo
19.
Toxins (Basel) ; 11(11)2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752210

RESUMO

Assassin bugs (Reduviidae) produce venoms that are insecticidal, and which induce pain in predators, but the composition and function of their individual venom components is poorly understood. We report findings on the venom system of the red-spotted assassin bug Platymeris rhadamanthus, a large species of African origin that is unique in propelling venom as a projectile weapon when threatened. We performed RNA sequencing experiments on venom glands (separate transcriptomes of the posterior main gland, PMG, and the anterior main gland, AMG), and proteomic experiments on venom that was either defensively propelled or collected from the proboscis in response to electrostimulation. We resolved a venom proteome comprising 166 polypeptides. Both defensively propelled venom and most venom samples collected in response to electrostimulation show a protein profile similar to the predicted secretory products of the PMG, with a smaller contribution from the AMG. Pooled venom samples induce calcium influx via membrane lysis when applied to mammalian neuronal cells, consistent with their ability to cause pain when propelled into the eyes or mucus membranes of potential predators. The same venom induces rapid paralysis and death when injected into fruit flies. These data suggest that the cytolytic, insecticidal venom used by reduviids to capture prey is also a highly effective defensive weapon when propelled at predators.


Assuntos
Venenos de Artrópodes/toxicidade , Comportamento Animal , Heterópteros/metabolismo , Sequência de Aminoácidos , Animais , Venenos de Artrópodes/química , Venenos de Artrópodes/genética , Heterópteros/fisiologia , Análise de Sequência de RNA , Homologia de Sequência de Aminoácidos , Transcriptoma
20.
BMC Ophthalmol ; 19(1): 204, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601186

RESUMO

BACKGROUND: The metabolic activity of retina is higher than other human tissues and is crucial to the vision. Cynomolgus macaques is widely used in ophthalmic disease research. The evaluation and comparison of macular and optic disc vascular circulation parameters between normal adult cynomolgus macaques and healthy adult humans using OCT-A can promote better use of nonhuman primate models in studies of ophthalmic vascular disease. METHODS: Twelve normal adult cynomolgus macaques with a mean age of 4.91 ± 0.43 years were studied for data collection. The macula of 28 adult healthy humans (14 males and 14 females), with a mean age of 25.11 ± 6.21 years and the optic discs of 9 adult healthy humans (4 males and 5 females) with a mean age of 28.56 ± 6.78 years were measured. The vessel density (VD) was measured using an RTVue XR with AngioVue. The scan sizes of the macular and optic discs were 3 × 3 mm and 4.5 × 4.5 mm, respectively. RESULTS: OCT-A can image the superficial and deep capillary plexuses and radial peripapillary capillary network. In RPC layer of the optic disc, the VD in the nasal quadrant was lower than the VD in the inferior temporal quadrant. Similarities and significant differences in VD between healthy humans and cynomolgus macaques were obtained using OCT-A. CONCLUSIONS: This study provides normal vascular parameters for adult cynomolgus macaques using OCT-A to help establish an optical parameter database for cynomolgus macaques and compare VD between healthy humans and cynomolgus macaques to promote choroid-retinopathy research. TRIAL REGISTRATION: Current Controlled Trials NCT03692169 , retrospectively registered on 26 sept 2018.


Assuntos
Angiofluoresceinografia/métodos , Disco Óptico/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adulto , Animais , Feminino , Fundo de Olho , Humanos , Macaca fascicularis , Masculino , Modelos Animais , Valores de Referência
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