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1.
Physiol Plant ; 175(3): e13924, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37158623

RESUMO

Interconduit pit membranes, which are permeable regions in the primary cell wall that connect to adjacent conduits, play a crucial role in water relations and the movement of nutrients between xylem conduits. However, how pit membrane characteristics might influence water-carbon coupling remains poorly investigated in cycads. We examined pit characteristics, the anatomical and photosynthetic traits of 13 cycads from a common garden, to determine if pit traits and their coordination are related to water relations and carbon economy. We found that the pit traits of cycads were highly variable and that cycads exhibited a similar tradeoff between pit density and pit area as other plant lineages. Unlike other plant lineages (1) pit membranes, pit apertures, and pit shapes of cycads were not coordinated as in angiosperms; (2) cycads exhibited larger pit membrane areas but lower pit densities relative to ferns and angiosperms, but smaller and similar pit membrane densities to non-cycad gymnosperms; (3) cycad pit membrane areas and densities were partially coordinated with anatomical traits, with hydraulic supply of the rachis positively coordinated with photosynthesis, whereas pit aperture areas and fractions were negatively coordinated with photosynthetic traits; (4) cycad pit traits reflected adaptation to wetter habitats for Cycadaceae and drier habitats for Zamiaceae. The large variation in pit traits, the unique pit membrane size and density, and the partial coordination of pit traits with anatomical and physiological traits of the rachis and pinna among cycads may have facilitated their dominance in a variety of ecosystems from the Mesozoic to modern times.


Assuntos
Cycadopsida , Ecossistema , Cycadopsida/metabolismo , Fotossíntese , Plantas/metabolismo , Água/metabolismo , Carbono
2.
PLoS Genet ; 16(10): e1009009, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33085662

RESUMO

Drug-resistant mutations often have deleterious impacts on replication fitness, posing a fitness cost that can only be overcome by compensatory mutations. However, the role of fitness cost in the evolution of drug resistance has often been overlooked in clinical studies or in vitro selection experiments, as these observations only capture the outcome of drug selection. In this study, we systematically profile the fitness landscape of resistance-associated sites in HIV-1 protease using deep mutational scanning. We construct a mutant library covering combinations of mutations at 11 sites in HIV-1 protease, all of which are associated with resistance to protease inhibitors in clinic. Using deep sequencing, we quantify the fitness of thousands of HIV-1 protease mutants after multiple cycles of replication in human T cells. Although the majority of resistance-associated mutations have deleterious effects on viral replication, we find that epistasis among resistance-associated mutations is predominantly positive. Furthermore, our fitness data are consistent with genetic interactions inferred directly from HIV sequence data of patients. Fitness valleys formed by strong positive epistasis reduce the likelihood of reversal of drug resistance mutations. Overall, our results support the view that strong compensatory effects are involved in the emergence of clinically observed resistance mutations and provide insights to understanding fitness barriers in the evolution and reversion of drug resistance.


Assuntos
Farmacorresistência Viral/genética , Epistasia Genética , Infecções por HIV/tratamento farmacológico , Protease de HIV/genética , HIV-1/genética , Aptidão Genética/genética , Infecções por HIV/genética , Infecções por HIV/virologia , Protease de HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Mutação/genética , Inibidores de Proteases/efeitos adversos , Inibidores de Proteases/uso terapêutico , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
3.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144834

RESUMO

Perilla frutescens (L.) Britt. (Labiatae), a medicinal plant, has been widely used for the therapy of multiple diseases since about 1800 years ago. It has been demonstrated that the extracts of P. frutescens exert significant anti-inflammatory effects. In this research, two pairs of 7,7'-cyclolignan enantiomers, possessing a cyclobutane moiety, (+)/(-)-perfrancin [(+)/(-)-1] and (+)/(-)-magnosalin [(+)/(-)-2], were separated from P. frutescens leaves. The present study achieved the chiral separation and determined the absolute configuration of (±)-1 and (±)-2. Compounds (+)-1 and (-)-1 have notable anti-inflammatory effects by reducing the secretion of pro-inflammatory factors (NO, TNF-α and IL-6) and the expression of pro-inflammatory mediators (iNOS and COX-2). These findings indicate that cyclolignans are effective substances of P. frutescens with anti-inflammatory activity. The present study partially elucidates the mechanisms underlying the effects of P. frutescens.


Assuntos
Ciclobutanos , Perilla frutescens , Perilla , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2 , Mediadores da Inflamação , Interleucina-6 , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa
4.
BMC Cancer ; 21(1): 532, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971833

RESUMO

BACKGROUND: The clinical staging systems for adenocarcinoma of the esophagogastric junction (AEG) are controversial. We aimed to propose a prognostic nomogram based on real-world data for predicting survival of Siewert type II/III AEG patients after surgery. METHODS: A total of 396 patients with Siewert type II/III AEG diagnosed and treated at the Center for Gastrointestinal Surgery, the First Affiliated Hospital, Sun Yat-sen University, from June 2009 to June 2017 were enrolled. The original data of 29 variables were exported from the electronic medical records system. The nomogram was established based on multivariate Cox regression coefficients, and its performance was measured using Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve analysis and calibration curve. RESULTS: A nomogram was constructed based on nine variables. The C-index for overall survival (OS) prediction was 0.76 (95% CI, 0.72 to 0.80) in the training cohort, in the validation-1 cohort was 0.79 (95% CI, 0.72 to 0.86), and 0.73 (95% CI, 0.67 to 0.80) in the validation-2 cohort. Time-dependent ROC curves and calibration curves in all three cohorts showed good prognostic predictive accuracy. We further proved the superiority of the nomogram in predictive accuracy for OS to pathological TNM (pTNM) staging system and other independent prognostic factors. Kaplan-Meier survival curves demonstrated the pTNM stage, grade of differentiation, positive lymph node, log odds of positive lymph node and organ invasion were prognostic factors with good discriminative ability. CONCLUSION: The established nomogram demonstrated a more precise prognostic prediction for patients with Siewert type II/III AEG.


Assuntos
Adenocarcinoma/mortalidade , Neoplasias Esofágicas/mortalidade , Junção Esofagogástrica , Nomogramas , Neoplasias Gástricas/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/patologia
5.
Neuroradiology ; 62(3): 327-334, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31822931

RESUMO

PURPOSE: Mild cognitive impairment (MCI) is commonly observed in Parkinson's disease (PD), even in the early stages. However, the neural substrates of cognitive impairment in PD remain unclear. The aim of the current study was to investigate the change of local brain function in PD patients with MCI. METHODS: Fifty patients with PD, including 25 PD patients with MCI (PD-MCI) and 25 PD patients with normal cognition (PD-NC), and 25 age- and sex-matched healthy controls (HC) were enrolled. Conventional magnetic resonance imaging (MRI), 3D structural images, and resting state-functional MRI (rs-fMRI) were performed in all subjects. Regional homogeneity (ReHo) was measured based on the rs-fMRI images to investigate the altered local brain functions. RESULTS: Brain regions with decreased ReHo were located in the left posterior cerebellar lobe in PD sub-groups compared to the HC group, and the brain regions with increased ReHo were located in the limbic lobe (right precuneus/bilateral middle cingulate cortex) in PD-MCI compared with HC group. PD-MCI presented with increased ReHo in the bilateral precuneus/left superior parietal lobe and decreased ReHo in the left insula compared to PD-NC. ReHo values for the left precuneus were negatively related to neuropsychological scores, and ReHo values for the left insula were positively related to neuropsychological scores in PD subjects. CONCLUSION: The present study demonstrated abnormal spontaneous synchrony in the left insula and left precuneus in patients with PD-MCI compared to PD-NC, which might provide a novel insight into the diagnosis and clinical treatment of cognitive impairment in PD.


Assuntos
Disfunção Cognitiva/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Molecules ; 25(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066297

RESUMO

Metal-Organic Framework (MOF) materials are often modified or functionalized, and then the crystal size and morphology of MOF materials are changed. In the process of preparing UiO-66 confined phosphomolybdic acid (PMA) composites (PU), the TiF4-modified PU (PMA + UiO-66) composite catalyst (TiF4-PU) was successfully synthesized by adding titanium tetrafluoride, and the catalytic desulfurization activity was excellent. Similarly, the reaction mechanism was investigated by means of infrared spectroscopy, Raman spectroscopy, XPS, and UV/Vis spectroscopy. The results show that the addition of TiF4 not only changes the appearance and color of the catalyst, but also changes the valence distribution of the elements in the catalyst. The number of oxygen vacancies in the MOF increases due to the addition of TiF4, and more electrons are transferred from the Zr-MOF to PMA to form more Mo5+, which improved the performance of oxidative desulfurization in comparison. Thus, a stronger strong metal-support interaction (SMSI) effect is observed for TiF4-modified PU catalysts. In addition, the quenching experiment of free radicals shows that ·OH radical is the main active substance in the oxidative desulfurization reaction over TiF4-PU catalyst.


Assuntos
Fluoretos/química , Estruturas Metalorgânicas/química , Molibdênio/química , Ácidos Fosfóricos/química , Titânio/química , Cor , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Compostos Organometálicos/química , Espectroscopia Fotoeletrônica , Ácidos Ftálicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
7.
PLoS Pathog ; 13(8): e1006541, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28787455

RESUMO

Certain Major Histocompatibility-I (MHC-I) types are associated with superior immune containment of HIV-1 infection by CD8+ cytotoxic T lymphocytes (CTLs), but the mechanisms mediating this containment are difficult to elucidate in vivo. Here we provide controlled assessments of fitness landscapes and CTL-imposed constraints for immunodominant epitopes presented by two protective (B*57 and B*27) and one non-protective (A*02) MHC-I types. Libraries of HIV-1 with saturation mutagenesis of CTL epitopes are propagated with and without CTL selective pressure to define the fitness landscapes for epitope mutation and escape from CTLs via deep sequencing. Immunodominant B*57- and B*27- present epitopes are highly limited in options for fit mutations, with most viable variants recognizable by CTLs, whereas an immunodominant A*02 epitope-presented is highly permissive for mutation, with many options for CTL evasion without loss of viability. Generally, options for evasion overlap considerably between CTL clones despite highly distinct T cell receptors. Finally, patterns of variant recognition suggest population-wide CTL selection for the A*02-presented epitope. Overall, these findings indicate that these protective MHC-I types yield CTL targeting of highly constrained epitopes, and underscore the importance of blocking public escape pathways for CTL-based interventions against HIV-1.


Assuntos
Apresentação de Antígeno/imunologia , Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Linfócitos T Citotóxicos/imunologia , HIV-1/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Evasão da Resposta Imune/imunologia , Epitopos Imunodominantes/imunologia , Mutagênese Sítio-Dirigida , Viremia/imunologia
8.
Clin Infect Dis ; 67(5): 791-794, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-29933437

RESUMO

Dolutegravir (DTG) is a preferred drug for initial treatment of human immunodeficiency virus type 1 infection. We present next-generation sequencing analysis of integrase genotypes during a period of virologic failure in a treatment-naive man who initiated tenofovir disoproxil fumarate/emtricitabine plus DTG.


Assuntos
Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Integrases/genética , Terapia Antirretroviral de Alta Atividade , Genótipo , HIV-1/enzimologia , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Oxazinas , Piperazinas , Piridonas , Análise de Sequência de DNA , Falha de Tratamento
9.
BMC Genomics ; 17: 108, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26868371

RESUMO

BACKGROUND: The high error rate of next generation sequencing (NGS) restricts some of its applications, such as monitoring virus mutations and detecting rare mutations in tumors. There are two commonly employed sequencing library preparation strategies to improve sequencing accuracy by correcting sequencing errors: read-pairing method and tag-clustering method (i.e. primer ID or UID). Here, we constructed a homogeneous library from a single clone, and compared the variant calling accuracy of these error-correction methods. RESULT: We comprehensively described the strengths and pitfalls of these methods. We found that both read-pairing and tag-clustering methods significantly decreased sequencing error rate. While the read-pairing method was more effective than the tag-clustering method at correcting insertion and deletion errors, it was not as effective as the tag-clustering method at correcting substitution errors. In addition, we observed that when the read quality was poor, the tag-clustering method led to huge coverage loss. We also tested the effect of applying quality score filtering to the error-correction methods and demonstrated that quality score filtering was able to impose a minor, yet statistically significant improvement to the error-correction methods tested in this study. CONCLUSION: Our study provides a benchmark for researchers to select suitable error-correction methods based on the goal of the experiment by balancing the trade-off between sequencing cost (i.e. sequencing coverage requirement) and detection sensitivity.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/normas , Reprodutibilidade dos Testes
10.
BMC Genomics ; 17: 46, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26754751

RESUMO

BACKGROUND: Epistasis is one of the central themes in viral evolution due to its importance in drug resistance, immune escape, and interspecies transmission. However, there is a lack of experimental approach to systematically probe for epistatic residues. RESULTS: By utilizing the information from natural occurring sequences and high-throughput genetics, this study established a novel strategy to identify epistatic residues. The rationale is that a substitution that is deleterious in one strain may be prevalent in nature due to the presence of a naturally occurring compensatory substitution. Here, high-throughput genetics was applied to influenza A virus M segment to systematically identify deleterious substitutions. Comparison with natural sequence variation showed that a deleterious substitution M1 Q214H was prevalent in circulating strains. A coevolution analysis was then performed and indicated that M1 residues 121, 207, 209, and 214 naturally coevolved as a group. Subsequently, we experimentally validated that M1 A209T was a compensatory substitution for M1 Q214H. CONCLUSIONS: This work provided a proof-of-concept to identify epistatic residues by coupling high-throughput genetics with phylogenetic information. In particular, we were able to identify an epistatic interaction between M1 substitutions A209T and Q214H. This analytic strategy can potentially be adapted to study any protein of interest, provided that the information on natural sequence variants is available.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Vírus da Influenza A/genética , Filogenia , Proteínas da Matriz Viral/genética , Substituição de Aminoácidos , Epistasia Genética , Humanos , Vírus da Influenza A/patogenicidade , Deleção de Sequência/genética
11.
Behav Brain Res ; 459: 114794, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38056710

RESUMO

BACKGROUND: Elderly patients experience postoperative cognitive impairment frequently; therefore, effective interventions are urgently needed. Central nervous inflammation characterized by microglia may promote the progression of POCD by reducing synaptic plasticity. Notably, clinical studies revealed that the incidence of female patients was significantly lower than that of male patients. Besides, the brain estrogens have an anti-inflammatory effect and regulate the microglia at the same times. This study aimed to determine whether suppressing microglia overactivation by hippocampal estrogens can rescue the decrease of synaptic plasticity after surgery and anesthesia. METHODS: Exploratory laparotomy was used to establish the POCD model in 15-month-old male or female C57BL/6 J mice and animal behavioral tests were performed to test hippocampal-dependent memory capacity. Western blot and immunofluorescence were used to detect the microglial activation and plasticity related protein expressions. Elisa was used to detect the content of estrogens in the hippocampus. Estrogens and estrogen receptor inhibitor were used to replenish the estrogens in the brain and inhibit the effect of estrogens. RESULTS: Surgery and anesthesia did not cause POCD in female mice (P > 0.05), while the cognitive function decreased significantly after estrogen receptor inhibitor was given(P < 0.05). Male mice experienced cognitive dysfunction after surgery and anesthesia, and their cognitive function improved after estrogens supplementation (P < 0.05). Given estrogens and estrogen receptor inhibitors at the same time, the cognitive function of male mice could not be saved (P < 0.05). By correlation analysis, there was a negative correlation between the content of hippocampal estrogens and microglia (P < 0.05). The number or degree of activation of microglia affected the synaptic plasticity, which ultimately regulated the cognitive function of mice. CONCLUSION: Hippocampal estrogens rescued the decline of synaptic plasticity after surgery and anesthesia by inhibiting microglia overactivation.


Assuntos
Anestesia , Disfunção Cognitiva , Humanos , Masculino , Feminino , Animais , Camundongos , Idoso , Lactente , Microglia , Estrogênios/farmacologia , Estrogênios/metabolismo , Camundongos Endogâmicos C57BL , Disfunção Cognitiva/etiologia , Anestesia/efeitos adversos , Receptores de Estrogênio/metabolismo , Hipocampo/metabolismo
12.
Insects ; 15(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38392541

RESUMO

The functional anatomy of the split compound eyes of whirligig beetles Dineutus mellyi (Coleoptera: Gyrinidae) was examined by advanced microscopy and microcomputed tomography. We report the first 3D visualization and analysis of the split compound eyes. On average, the dorsal and ventral eyes contain 1913 ± 44.5 facets and 3099 ± 86.2 facets, respectively. The larger area of ventral eyes ensures a higher field of vision underwater. The ommatidium of the split compound eyes is made up of laminated cornea lenses that offer protection against mechanical injuries, bullet-shaped crystalline cones that guide light to the photoreceptive regions, and screening pigments that ensure directional light passage. The photoreceptive elements, made up of eight retinular cells, exhibit a tri-tiered rhabdom structure, including the upper distal rhabdom, a clear zone that ensures maximum light passage, and an enlarged lower distal rhabdom that ensures optimal photon capture.

13.
J Ethnopharmacol ; 319(Pt 3): 117337, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37866462

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Chuanxiong, the rhizome of Ligusticum chuanxiong Hort., is an ancient herbal medicine that has gained extensive popularity in alleviating migraines with satisfying therapeutic effects in China. As the major bioactive component of Chuanxiong, the essential oil also exerts a marked impact on the treatment of migraine. It is widely recognized that neuroinflammation contributes to migraine. However, it remains unknown whether Chuanxiong essential oil has anti-neuroinflammatory activity. AIM OF THE STUDY: To explore the anti-neuroinflammatory properties of Chuanxiong essential oil and its molecular mechanisms by network pharmacology analysis and in vitro experiments. MATERIALS AND METHODS: Gas chromatography-mass spectrometry (GC-MS) was used to identify the chemical components of Chuanxiong essential oil. Public databases were used to predict possible targets, build the protein-protein interaction network (PPI), and perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Moreover, cytological experiments, nitric oxide assay, enzyme-link immunosorbent assay, western blotting, and immunofluorescence assay were adopted to prove the critical signaling pathway in lipopolysaccharide (LPS)-induced BV2 cells. RESULTS: Thirty-six compounds were identified from Chuanxiong essential oil by GC-MS, and their corresponding putative targets were predicted. The network pharmacology study identified 232 candidate targets of Chuanxiong essential oil in anti-neuroinflammation. Furthermore, Chuanxiong essential oil was found to potentially affect the C-type lectin receptor, FoxO, and NF-κB signaling pathways according to the KEGG analysis. Experimentally, we verified that Chuanxiong essential oil could significantly reduce the overproduction of inflammatory mediators and pro-inflammatory factors via the NF-κB signaling pathway. CONCLUSION: Chuanxiong essential oil alleviates neuroinflammation through the NF-κB signaling pathway, which provides a theoretical foundation for a better understanding of the clinical application of Chuanxiong essential oil in migraine treatment.


Assuntos
Ligusticum , Transtornos de Enxaqueca , NF-kappa B , Lipopolissacarídeos/toxicidade , Farmacologia em Rede , Doenças Neuroinflamatórias
14.
AIDS ; 38(3): 329-337, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37861675

RESUMO

OBJECTIVES: To describe the clinical and virologic characteristics of HIV-HBV coinfection, including the predictors of high maternal HBV viral load in pregnant women with HIV in sub-Saharan Africa (SSA). METHODS: HPTN 046 was a HIV perinatal transmission clinical trial evaluating infant nevirapine vs. placebo. Women-infant pairs ( n  = 2016) were enrolled in SSA from 2007 to 2010; 1579 (78%) received antiretrovirals (ARV). Maternal delivery samples were retrospectively tested for hepatitis B surface antigen (HBsAg), and if positive, were tested for hepatitis B e antigen (HBeAg) and HBV viral load (VL). High HBV VL was defined as ≥10 6  IU/ml. RESULTS: Overall, 4.4% (88/2016) had HBV co-infection, with geographic variability ranging from 2.4% to 8.7% ( P  < 0.0001); 25% (22/88) were HBeAg positive with prevalence in countries ranging from 10.5% to 39%. Fifty-two percentage (40/77) of those with HBV received ARV, the majority (97%) received 3TC as the only HBV active agent. HBeAg positivity was associated with high maternal HBV VL, odds ratio (OR) 37.0, 95% confidence interval (CI) 5.4-252.4. Of those with high HBV VL, 40% (4/10) were receiving HBV active drugs (HBV-ARV). HBV drug resistance occurred in 7.5% (3/40) receiving HBV-ARV. CONCLUSIONS: In SSA, HBV co-infection is common in pregnant women with HIV. HBsAg and HBeAg prevalence vary widely by country in this clinical trial cohort. HBeAg is a surrogate for high HBV viral load. HBV drug resistance occurred in 7.5% receiving HBV-ARV with lamivudine as the only HBV active agent. These findings reinforce the importance of HBsAg screening and early treatment with two active agents for HBV.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Feminino , Humanos , Lactente , Gravidez , África Subsaariana/epidemiologia , Antirretrovirais/uso terapêutico , Coinfecção/tratamento farmacológico , DNA Viral , Hepatite B/tratamento farmacológico , Hepatite B/epidemiologia , Antígenos E da Hepatite B/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Lamivudina/uso terapêutico , Estudos Retrospectivos , Carga Viral
15.
Front Plant Sci ; 14: 1130724, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324689

RESUMO

Flowers are critical for successful reproduction and have been a major axis of diversification among angiosperms. As the frequency and severity of droughts are increasing globally, maintaining water balance of flowers is crucial for food security and other ecosystem services that rely on flowering. Yet remarkably little is known about the hydraulic strategies of flowers. We characterized hydraulic strategies of leaves and flowers of ten species by combining anatomical observations using light and scanning electron microscopy with measurements of hydraulic physiology (minimum diffusive conductance (g min) and pressure-volume (PV) curves parameters). We predicted that flowers would exhibit higher g min and higher hydraulic capacitance than leaves, which would be associated with differences in intervessel pit traits because of their different hydraulic strategies. We found that, compared to leaves, flowers exhibited: 1) higher g min, which was associated with higher hydraulic capacitance (C T); 2) lower variation in intervessel pit traits and differences in pit membrane area and pit aperture shape; and 3) independent coordination between intervessel pit traits and other anatomical and physiological traits; 4) independent evolution of most traits in flowers and leaves, resulting in 5) large differences in the regions of multivariate trait space occupied by flowers and leaves. Furthermore, across organs intervessel pit trait variation was orthogonal to variation in other anatomical and physiological traits, suggesting that pit traits represent an independent axis of variation that have as yet been unquantified in flowers. These results suggest that flowers, employ a drought-avoidant strategy of maintaining high capacitance that compensates for their higher g min to prevent excessive declines in water potentials. This drought-avoidant strategy may have relaxed selection on intervessel pit traits and allowed them to vary independently from other anatomical and physiological traits. Furthermore, the independent evolution of floral and foliar anatomical and physiological traits highlights their modular development despite being borne from the same apical meristem.

16.
Phytochemistry ; 209: 113613, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36804478

RESUMO

Three unprecedented thioether-linked dimeric pyrimidines, namely ligusticumines A-C, together with twelve known compounds were isolated and identified from the traditional Chinese medicinal-edible herb, Ligusticum striatum DC. The structures of all the isolated compounds were determined from NMR, HRESIMS and X-ray diffraction spectroscopies. Additionally, a novel 3-step synthetic route was developed to synthesize ligusticumine C by substitution, thiolation and coupling, with an overall yield of 5.4%. The inhibitory activities of the isolated compounds against phosphatidylinositol 3-kinase (PI3K) were tested, of which, (3S)-butylphthalide, a characteristic component of L. striatum, showed a potent inhibitory effect on PI3Kα (IC50: 3.6 µg/mL).


Assuntos
Ligusticum , Plantas Medicinais , Ligusticum/química , Fosfatidilinositol 3-Quinases , Pirimidinas/química , Pirimidinas/farmacologia , Espectroscopia de Ressonância Magnética
17.
J Integr Med ; 21(5): 496-508, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37517892

RESUMO

OBJECTIVE: This work explores the impact of electroacupuncture (EA) on acute postoperative pain (APP) and the role of stimulator of interferon genes/type-1 interferon (STING/IFN-1) signaling pathway modulation in the analgesic effect of EA in APP rats. METHODS: The APP rat model was initiated through abdominal surgery and the animals received two 30 min sessions of EA at bilateral ST36 (Zusanli) and SP6 (Sanyinjiao) acupoints. Mechanical, thermal and cold sensitivity tests were performed to measure the pain threshold, and electroencephalograms were recorded in the primary somatosensory cortex to identify the effects of EA treatment on APP. Western blotting and immunofluorescence were used to examine the expression and distribution of proteins in the STING/IFN-1 pathway as well as neuroinflammation. A STING inhibitor (C-176) was administered intrathecally to verify its role in EA. RESULTS: APP rats displayed mechanical and thermal hypersensitivities compared to the control group (P < 0.05). APP significantly reduced the amplitude of θ, α and γ oscillations compared to their baseline values (P < 0.05). Interestingly, expression levels of proteins in the STING/IFN-1 pathway were downregulated after inducing APP (P < 0.05). Further, APP increased pro-inflammatory factors, including interleukin-6, tumor necrosis factor-α and inducible nitric oxide synthase, and downregulated anti-inflammatory factors, including interleukin-10 and arginase-1 (P < 0.05). EA effectively attenuated APP-induced painful hypersensitivities (P < 0.05) and restored the θ, α and γ power in APP rats (P < 0.05). Meanwhile, EA distinctly activated the STING/IFN-1 pathway and mitigated the neuroinflammatory response (P < 0.05). Furthermore, STING/IFN-1 was predominantly expressed in isolectin-B4- or calcitonin-gene-related-peptide-labeled dorsal root ganglion neurons and superficial laminae of the spinal dorsal horn. Inhibition of the STING/IFN-1 pathway by intrathecal injection of C-176 weakened the analgesic and anti-inflammatory effects of EA on APP (P < 0.05). CONCLUSION: EA can generate robust analgesic and anti-inflammatory effects on APP, and these effects may be linked to activating the STING/IFN-1 pathway, suggesting that STING/IFN-1 may be a target for relieving APP. Please cite this article as: Ding YY, Xu F, Wang YF, Han LL, Huang SQ, Zhao S, Ma LL, Zhang TH, Zhao WJ, Chen XD. Electroacupuncture alleviates postoperative pain through inhibiting neuroinflammation via stimulator of interferon genes/type-1 interferon pathway. J Integr Med. 2023; 21(5): 496-508.


Assuntos
Eletroacupuntura , Doenças Neuroinflamatórias , Ratos , Animais , Ratos Sprague-Dawley , Dor Pós-Operatória , Interferons
18.
Zookeys ; 1177: 23-40, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692325

RESUMO

The first exploratory study was conducted on the compound eye morphology and spectral characteristics of Agasicleshygrophila (Selman & Vogt, 1971) to clarify its eye structure and its spectral sensitivity. Scanning electron microscopy, paraffin sectioning, and transmission electron microscopy revealed that A.hygrophila has apposition compound eyes with both eucones and open rhabdom. The micro-computed tomography (CT) results after 3D reconstruction demonstrated the precise position of the compound eyes in the insect's head and suggested that the visual range was mainly concentrated in the front and on both sides of the head. The electroretinogram (ERG) experiment showed that red, yellow, green, blue, and ultraviolet light could stimulate the compound eyes of A.hygrophila to produce electrical signals. The behavioural experiment results showed that both males and females had the strongest phototaxis to yellow light and positive phototaxis to red, green, and blue light but negative phototaxis to UV light. This study of the compound eyes of A.hygrophila will be helpful for decoding its visual mechanism in future studies.

19.
mSystems ; 8(5): e0067023, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37772870

RESUMO

IMPORTANCE: NA is a crucial surface antigen and drug target of influenza A virus. A comprehensive understanding of NA's mutational effect and drug resistance profiles in vivo is essential for comprehending the evolutionary constraints and making informed choices regarding drug selection to combat resistance in clinical settings. In the current study, we established an efficient deep mutational screening system in mouse lung tissues and systematically evaluated the fitness effect and drug resistance to three neuraminidase inhibitors of NA single-nucleotide mutations. The fitness of NA mutants is generally correlated with a natural mutation in the database. The fitness of NA mutants is influenced by biophysical factors such as protein stability, complex formation, and the immune response triggered by viral infection. In addition to confirming previously reported drug-resistant mutations, novel mutations were identified. Interestingly, we identified an allosteric drug-resistance mutation that is not located within the drug-binding pocket but potentially affects drug binding by interfering with NA tetramerization. The dual assessments performed in this study provide a more accurate assessment of the evolutionary potential of drug-resistant mutations and offer guidance for the rational selection of antiviral drugs.


Assuntos
Farmacorresistência Viral , Vírus da Influenza A , Neuraminidase , Animais , Camundongos , Antivirais/farmacologia , Vírus da Influenza A/genética , Mutação/genética , Neuraminidase/genética , Oseltamivir/farmacologia
20.
Sci Bull (Beijing) ; 68(15): 1662-1677, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37481436

RESUMO

Martynoside (MAR), a bioactive component in several well-known tonic traditional Chinese herbs, exhibits pro-hematopoietic activity during 5-fluorouracil (5-FU) treatment. However, the molecular target and the mechanism of MAR are poorly understood. Here, by adopting the mRNA display with a library of even-distribution (md-LED) method, we systematically examined MAR-protein interactions in vitro and identified the ribosomal protein L27a (RPL27A) as a key cellular target of MAR. Structural and mutational analysis confirmed the specific interaction between MAR and the exon 4,5-encoded region of RPL27A. MAR attenuated 5-FU-induced cytotoxicity in bone marrow nucleated cells, increased RPL27A protein stability, and reduced the ubiquitination of RPL27A at lys92 (K92) and lys94 (K94). Disruption of MAR binding at key residues of RPL27A completely abolished the MAR-induced stabilization. Furthermore, by integrating label-free quantitative ubiquitination proteomics, transcriptomics, and ribosome function assays, we revealed that MAR restored RPL27A protein levels and thus rescued ribosome biogenesis impaired by 5-FU. Specifically, MAR increased mature ribosomal RNA (rRNA) abundance, prevented ribosomal protein degradation, facilitated ribosome assembly, and maintained nucleolar integrity. Collectively, our findings characterize the target of a component of Chinese medicine, reveal the importance of ribosome biogenesis in hematopoiesis, and open up a new direction for improving hematopoiesis by targeting RPL27A.


Assuntos
Bioensaio , Fluoruracila , Fluoruracila/farmacologia , Células da Medula Óssea , Cafeína
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