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1.
Plant Physiol ; 195(2): 1681-1693, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38478507

RESUMEN

Fusarium head blight (FHB), caused by Fusarium graminearum, causes huge annual economic losses in cereal production. To successfully colonize host plants, pathogens secrete hundreds of effectors that interfere with plant immunity and facilitate infection. However, the roles of most secreted effectors of F. graminearum in pathogenesis remain unclear. We analyzed the secreted proteins of F. graminearum and identified 255 candidate effector proteins by liquid chromatography-mass spectrometry (LC-MS). Five subtilisin-like family proteases (FgSLPs) were identified that can induce cell death in Nicotiana benthamiana leaves. Further experiments showed that these FgSLPs induced cell death in cotton (Gossypium barbadense) and Arabidopsis (Arabidopsis thaliana). A signal peptide and light were not essential for the cell death-inducing activity of FgSLPs. The I9 inhibitor domain and the entire C-terminus of FgSLPs were indispensable for their self-processing and cell death-inducing activity. FgSLP-induced cell death occurred independent of the plant signal transduction components BRI-ASSOCIATED KINASE 1 (BAK1), SUPPRESSOR OF BIR1 1 (SOBIR1), ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), and PHYTOALEXIN DEFICIENT 4 (PAD4). Reduced virulence was observed when FgSLP1 and FgSLP2 were simultaneously knocked out. This study reveals a class of secreted toxic proteins essential for F. graminearum virulence.


Asunto(s)
Arabidopsis , Muerte Celular , Fusarium , Nicotiana , Enfermedades de las Plantas , Fusarium/patogenicidad , Virulencia , Arabidopsis/microbiología , Arabidopsis/genética , Enfermedades de las Plantas/microbiología , Nicotiana/microbiología , Nicotiana/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Subtilisinas/metabolismo , Subtilisinas/genética , Gossypium/microbiología , Hojas de la Planta/microbiología , Células Vegetales/microbiología
2.
Plant Cell ; 34(5): 1768-1783, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35099562

RESUMEN

Perception of pathogen-associated molecular patterns (PAMPs) by plant cell surface-localized pattern-recognition receptors (PRRs) triggers the first line of plant innate immunity. In Arabidopsis thaliana, the receptor-like cytoplasmic kinase BRASSINOSTEROID-SIGNALING KINASE1 (BSK1) physically associates with PRR FLAGELLIN SENSING2 and plays an important role in defense against multiple pathogens. However, how BSK1 transduces signals to activate downstream immune responses remains elusive. Previously, through whole-genome phosphorylation analysis using mass spectrometry, we showed that phosphorylation of the mitogen-activated protein kinase (MAPK) MPK15 was affected in the bsk1 mutant compared with the wild-type plants. Here, we demonstrated that MPK15 is important for powdery mildew fungal resistance. PAMPs and fungal pathogens significantly induced the phosphorylation of MPK15 Ser-511, a key phosphorylation site critical for the functions of MPK15 in powdery mildew resistance. BSK1 physically associates with MPK15 and is required for basal and pathogen-induced MPK15 Ser-511 phosphorylation, which contributes to BSK1-mediated fungal resistance. Taken together, our data identified MPK15 as a player in plant defense against powdery mildew fungi and showed that BSK1 promotes fungal resistance in part by enhancing MPK15 Ser-511 phosphorylation. These results uncovered a mechanism of BSK1-mediated disease resistance and provided new insight into the role of MAPK phosphorylation in plant immunity.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Brasinoesteroides/metabolismo , Resistencia a la Enfermedad/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Moléculas de Patrón Molecular Asociado a Patógenos/metabolismo , Fosforilación , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/genética , Proteínas Serina-Treonina Quinasas/genética
3.
Proc Natl Acad Sci U S A ; 119(37): e2201503119, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36067285

RESUMEN

Spatial dynamics have long been recognized as an important driver of biodiversity. However, our understanding of species' coexistence under realistic landscape configurations has been limited by lack of adequate analytical tools. To fill this gap, we develop a spatially explicit metacommunity model of multiple competing species and derive analytical criteria for their coexistence in fragmented heterogeneous landscapes. Specifically, we propose measures of niche and fitness differences for metacommunities, which clarify how spatial dynamics and habitat configuration interact with local competition to determine coexistence of species. We parameterize our model with a Bayesian approach using a 36-y time-series dataset of three Daphnia species in a rockpool metacommunity covering >500 patches. Our results illustrate the emergence of interspecific variation in extinction and recolonization processes, including their dependencies on habitat size and environmental temperature. We find that such interspecific variation contributes to the coexistence of Daphnia species by reducing fitness differences and increasing niche differences. Additionally, our parameterized model allows separating the effects of habitat destruction and temperature change on species extinction. By integrating coexistence theory and metacommunity theory, our study provides platforms to increase our understanding of species' coexistence in fragmented heterogeneous landscapes and the response of biodiversity to environmental changes.


Asunto(s)
Biodiversidad , Extinción Biológica , Modelos Biológicos , Teorema de Bayes , Dinámica Poblacional
4.
New Phytol ; 241(1): 363-377, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37786257

RESUMEN

Nuclear pore complex (NPC) is composed of multiple nucleoporins (Nups). A plethora of studies have highlighted the significance of NPC in plant immunity. However, the specific roles of individual Nups are poorly understood. NUCLEAR PORE ANCHOR (NUA) is a component of NPC. Loss of NUA leads to an increase in SUMO conjugates and pleiotropic developmental defects in Arabidopsis thaliana. Herein, we revealed that NUA is required for plant defense against multiple pathogens. NUCLEAR PORE ANCHOR associates with the transcriptional corepressor TOPLESS-RELATED1 (TPR1) and contributes to TPR1 deSUMOylation. Significantly, NUA-interacting protein EARLY IN SHORT DAYS 4 (ESD4), a SUMO protease, specifically deSUMOylates TPR1. It has been previously established that the SUMO E3 ligase SAP AND MIZ1 DOMAIN-CONTAINING LIGASE 1 (SIZ1)-mediated SUMOylation of TPR1 represses the immune-related function of TPR1. Consistent with this notion, the hyper-SUMOylated TPR1 in nua-3 leads to upregulated expression of TPR1 target genes and compromised TPR1-mediated disease resistance. Taken together, our work uncovers a mechanism by which NUA positively regulates plant defense responses by coordination with ESD4 to deSUMOylate TPR1. Our findings, together with previous studies, reveal a regulatory module in which SIZ1 and NUA/ESD4 control the homeostasis of TPR1 SUMOylation to maintain proper immune output.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Inmunidad de la Planta , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Ligasas/metabolismo , Poro Nuclear/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Sumoilación
5.
Opt Express ; 32(7): 11221-11240, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38570975

RESUMEN

Laser-guided detector and infrared detection have attracted increasing attention in a wide range of research fields, including multispectral detection, radiative cooling, and thermal management. Previously reported absorbers presented shortcomings of lacking either tunability or compatibility. In this study, a metamaterial perfect absorber based on a Helmholtz resonator and fractal structure is proposed, which realizes tunable perfect absorptivity (α 1.06µ m >0.99,α 10.6µ m >0.99) of guided-laser radar dual operating bands (1.06 µm and 10.6 µm) and a low infrared average emissivity (ε¯3-5µ m =0.03,ε¯8-14µ m =0.31) in two atmospheric windows for compatible camouflage. The proposed perfect absorber provides a dynamically tunable absorptivity without structural changes and can be applied to optical communication, military stealth or protection, and electromagnetic detection.

6.
Opt Express ; 32(12): 21400-21411, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38859494

RESUMEN

Multi-mode multiplexing optical interconnection (MMOI) has been widely used as a new technology that can significantly expand communication bandwidth. However, the constant-on state of each channel in the existing MMOI systems leads to serious interference for receivers when extracting and processing information, necessitating introducing real-time selective-on function for each channel in MMOI systems. To achieve this goal, combining several practical requirements, we propose a real-time selective mode switch based on phase-change materials, which can individually tune the passing/blocking of different modes in the bus waveguide. We utilize our proposed particle swarm optimization algorithm with embedded neural network surrogate models (NN-in-PSO) to design this mode switch. The proposed NN-in-PSO significantly reduces the optimization cost, enabling multi-dimensional simultaneous optimization. The resulting mode switch offers several advantages, including ultra-compactness, rapid tuning, nonvolatility, and large extinction ratio. Then, we demonstrate the real-time channel selection function by integrating the mode switch into the MMOI system. Finally, we prove the fabricating robustness of the proposed mode switch, which paves the way for its large-scale application.

7.
Drug Resist Updat ; 68: 100957, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36990047

RESUMEN

Resistance to epidermal growth factor receptor (EGFR) inhibitors, from the first-generation erlotinib to the third generation osimertinib, is a clinical challenge in the treatment of patients with EGFR-mutant lung adenocarcinoma. Our previous work found that a novel allosteric inhibitor of phosphoglycerate mutase 1 (PGAM1), HKB99, restrains erlotinib resistance in lung adenocarcinoma cells. However, the role of HKB99 in osimertinib resistance and its underlying molecular mechanism remains to be elucidated. Herein, we found that IL-6/JAK2/STAT3 signaling pathway is aberrantly activated in both erlotinib and osimertinib resistant cells. Importantly, HKB99 significantly blocks the interaction of PGAM1 with JAK2 and STAT3 via the allosteric sites of PGAM1, which leads to inactivation of JAK2/STAT3 and thereby disrupts IL-6/JAK2/STAT3 signaling pathway. Consequently, HKB99 remarkably restores EGFR inhibitor sensitivity and exerts synergistic tumoricidal effect. Additionally, HKB99 alone or in combination with osimertinib down-regulated the level of p-STAT3 in xenograft tumor models. Collectively, this study identifies PGAM1 as a key regulator in IL-6/JAK2/STAT3 axis in the development of resistance to EGFR inhibitors, which could serve as a therapeutic target in lung adenocarcinoma with acquired resistance to EGFR inhibitors.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Clorhidrato de Erlotinib/farmacología , Clorhidrato de Erlotinib/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Interleucina-6/genética , Interleucina-6/farmacología , Interleucina-6/uso terapéutico , Fosfoglicerato Mutasa/metabolismo , Fosfoglicerato Mutasa/farmacología , Resistencia a Antineoplásicos , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Receptores ErbB , Transducción de Señal , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Mutación , Línea Celular Tumoral , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Janus Quinasa 2/farmacología
8.
Ecol Lett ; 26(8): 1325-1335, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37190868

RESUMEN

While the relationship between food web complexity and stability has been well documented, how complexity affects productivity remains elusive. In this study, we combine food web theory and a data set of 149 aquatic food webs to investigate the effect of complexity (i.e. species richness, connectance, and average interaction strength) on ecosystem productivity. We find that more complex ecosystems tend to be more productive, although different facets of complexity have contrasting effects. A higher species richness and/or average interaction strength increases productivity, whereas a higher connectance often decreases it. These patterns hold not only between realized complexity and productivity, but also characterize responses of productivity to simulated declines of complexity. Our model also predicts a negative association between productivity and stability along gradients of complexity. Empirical analyses support our predictions on positive complexity-productivity relationships and negative productivity-stability relationships. Our study provides a step forward towards reconciling ecosystem complexity, productivity and stability.


Asunto(s)
Ecosistema , Modelos Biológicos , Cadena Alimentaria , Biodiversidad
9.
Ecol Lett ; 26(1): 76-86, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36331162

RESUMEN

Understanding the formation of feeding links provides insights into processes underlying food webs. Generally, predators feed on prey within a certain body-size range, but a systematic quantification of such feeding niches is lacking. We developed a size-constrained feeding-niche (SCFN) model and parameterized it with information on both realized and non-realized feeding links in 72 aquatic and 65 terrestrial food webs. Our analyses revealed profound differences in feeding niches between aquatic and terrestrial predators and variation along a temperature gradient. Specifically, the predator-prey body-size ratio and the range in prey sizes increase with the size of aquatic predators, whereas they are nearly constant across gradients in terrestrial predator size. Overall, our SCFN model well reproduces the feeding relationships and predation architecture across 137 natural food webs (including 3878 species and 136,839 realized links). Our results illuminate the organisation of natural food webs and enables novel trait-based and environment-explicit modelling approaches.


Asunto(s)
Cadena Alimentaria , Conducta Predatoria , Animales , Tamaño Corporal , Modelos Teóricos
10.
Planta ; 257(3): 56, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36790514

RESUMEN

MAIN CONCLUSION: We developed a more realistic modeling framework by integrating stem photosynthesis into the canopy carbon assimilation model to compare the photosynthetic productivity between the stem and leaf of Eucalyptus urophylla plantations. Stems of Eucalyptus species with smooth outer bark have photosynthetic green tissue that can recycle internal stem CO2. However, the potential contribution of stem photosynthesis to forest productivity has not previously been adequately quantified, and we also do not know how it compares to leaf photosynthetic productivity. To assist in addressing this knowledge gap, we conducted field surveys in Eucalyptus urophylla plantations of different ages and developed a more realistic modeling framework by integrating stem photosynthesis into the existing canopy carbon assimilation model. We calculated the proportion of tree stems shaded by neighboring tree trunks based on Poisson spatial point process. Under the stand density of 2000 trees per hectare, the light absorption area of tree trunks of 2-year-old and 7-year-old E. urophylla plantations were 0.11 (± 0.15) and 0.35 (± 0.12) m2 stem m-2 land, the stem photosynthetic productivity (GPPstem) was 0.72 (± 0.45) and 1.81 (± 1.12) mol C m-2 month-1, and the ratios of GPPstem to leaf photosynthetic productivity (GPPleaf) were 5.10 and 8.17% for 2- and 7-year-old plantations, respectively. Overall, this study presents the feasibility of incorporating stem photosynthesis into the productivity prediction of E. urophylla plantations by developing the stem light absorption model.


Asunto(s)
Eucalyptus , Fotosíntesis , Árboles , Hojas de la Planta , Carbono
11.
BMC Public Health ; 23(1): 1973, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821916

RESUMEN

Dengue fever is one of the biggest threats to public health in China, causing huge disease burden and economic loss. Aedes-mosquito surveillance could be a cornerstone for predicting the risk of Aedes-borne diseases and evaluating the effect of vector management during diseases outbreaks. The human landing catch (HLC) method is regarded as the "gold standard" for catching Aedes mosquitoes, but it potentially exposes field professionals to vectors of known or unknown pathogens. Human-baited double net (HDN) was recommended to replace HLC for emergency monitoring in China when Aedes-borne diseases break out, but it had been reported with low efficiency for capturing Aedes mosquitoes. In this study, we compared HLC with HDN and BG traps for field Aedes albopictus monitoring, with the aim of evaluating the effectiveness of HDN replacing HLC and finding an effective and safe alternative to the HLC for monitoring Aedes albopictus. Six sites in Hangzhou, Shaoxing, and Yiwu, Zhejiang Province, China, were chosen to conduct outdoor HLC, HDN, and BG trap catches from June to October 2021. The tests were performed 3 h apart: 8:30-9:30 AM, 16:30-17:30 PM, and 17:30-18:30 PM. A total of 2330 adult mosquitoes were collected, and Aedes albopictus was the most abundant species in all three catches with 848(98.95%), 559(97.39%) and 867 (96.44%) caught in HLC, HDN and BG traps respectively. Compared to HLC, HDN collected significantly less Ae. albopictus and Ae. albopictus females per trapping period (P < 0.001, P < 0.001), whereas no statistical differences were found between the HLC and BG trap (P = 0.970, P > 0.05). Statistically significant positive spatial correlations for Ae. albopictus sampling was found between HLC and HDN traps (r = 0.543, P < 0.001) and HLC and BG traps (r = 0.658, P < 0.001). In conclusion, both the BG trap and HDN have a significant positive spatial correlation with HLC, making them safer alternatives to HLC for Ae. albopictus monitoring in China. However, with better a sampling efficiency, being less labor intensive, and no human-baited attraction bias, the BG trap could be a better choice than the HDN trap.


Asunto(s)
Aedes , Adulto , Animales , Femenino , Humanos , Control de Mosquitos/métodos , Mosquitos Vectores , China
12.
Plant J ; 107(3): 775-786, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33982335

RESUMEN

Nucleotide-binding site (NBS)-leucine-rich repeat (LRR) domain receptor (NLR) proteins play important roles in plant innate immunity by recognizing pathogen effectors. The Toll/interleukin-1 receptor (TIR)-NBS (TN) proteins belong to a subtype of the atypical NLRs, but their function in plant immunity is poorly understood. The well-characterized Arabidopsis thaliana typical coiled-coil (CC)-NBS-LRR (CNL) protein Resistance to Pseudomonas syringae 5 (RPS5) is activated after recognizing the Pseudomonas syringae type III effector AvrPphB. To explore whether the truncated TN proteins function in CNL-mediated immune signaling, we examined the interactions between the Arabidopsis TN proteins and RPS5, and found that TN13 and TN21 interacted with RPS5. However, only TN13, but not TN21, was involved in the resistance to P. syringae pv. tomato (Pto) strain DC3000 carrying avrPphB, encoding the cognate effector recognized by RPS5. Moreover, the regulation of Pto DC3000 avrPphB resistance by TN13 appeared to be specific, as loss of function of TN13 did not compromise resistance to Pto DC3000 hrcC- or Pto DC3000 avrRpt2. In addition, we demonstrated that the CC and NBS domains of RPS5 play essential roles in the interaction between TN13 and RPS5. Taken together, our results uncover a direct functional link between TN13 and RPS5, suggesting that TN13 acts as a partner in modulating RPS5-activated immune signaling, which constitutes a previously unknown mechanism for TN-mediated regulation of plant immunity.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/inmunología , Proteínas de la Membrana/metabolismo , Enfermedades de las Plantas/inmunología , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Proteínas de la Membrana/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Pseudomonas syringae
13.
Am Nat ; 200(4): 544-555, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36150194

RESUMEN

AbstractThe effects of dispersal on spatial synchrony and population variability have been well documented in theoretical research, and a growing number of empirical tests have been performed. Yet a synthesis is still lacking. Here, we conducted a meta-analysis of relevant experiments and examined how dispersal affected spatial synchrony and temporal population variability across scales. Our analyses showed that dispersal generally promoted spatial synchrony, and such effects increased with dispersal rate and decreased with environmental correlation among patches. The synchronizing effect of dispersal, however, was detected only when spatial synchrony was measured using the correlation-based index, not when the covariance-based index was used. In contrast to theoretical predictions, the effect of dispersal on local population variability was generally nonsignificant, except when environmental correlation among patches was negative and/or the experimental period was long. At the regional scale, while low dispersal stabilized metapopulation dynamics, high dispersal led to destabilization. Overall, the sign and strength of dispersal effects on spatial synchrony and population variability were modulated by taxa, environmental heterogeneity, type of perturbations, patch number, and experimental length. Our synthesis demonstrates that dispersal can affect the dynamics of spatially distributed populations, but its effects are context dependent on abiotic and biotic factors.


Asunto(s)
Ecosistema , Dinámica Poblacional
14.
Opt Express ; 30(11): 18250-18263, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36221630

RESUMEN

Infrared (IR) stealth with thermal management is highly desirable in military applications and astronomy. However, developing selective IR emitters with properties suitable for IR stealth and thermal management is challenging. In this study, we present the theoretical framework for a selective emitter based on an inverse-designed metasurface for IR stealth with thermal management. The emitter comprises an inverse-designed gold grating, a Ge2Sb2Te5 (GST) dielectric layer, and a gold reflective layer. The hat-like function, which describes an ideal thermal selective emitter, is involved in the inverse design algorithm. The emitter exhibits high performance in IR stealth with thermal management, with the low emissivity (ɛ3-5 µm =0.17; ɛ8-14 µm =0.16) for dual-band atmospheric transmission windows and high emissivity (ɛ5-8 µm =0.85) for non-atmospheric windows. Moreover, the proposed selective emitter can realize tunable control of thermal radiation in the wavelength range of 3-14 µm by changing the crystallization fraction of GST. In addition, the polarization-insensitive structure supports strong selective emission at large angles (60°). Thus, the selective emitter has potential for IR stealth, thermal imaging, and mid-infrared multifunctional equipment.

15.
Glob Chang Biol ; 28(16): 4962-4976, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35596650

RESUMEN

Understanding the history and regional singularities of human impact on vegetation is key to developing strategies for sustainable ecosystem management. In this study, fossil and modern pollen datasets from China are employed to investigate temporal changes in pollen composition, analogue quality, and pollen diversity during the Holocene. Anthropogenic disturbance and vegetation's responses are also assessed. Results reveal that pollen assemblages from non-forest communities fail to provide evidence of human impact for the western part of China (annual precipitation less than 400 mm and/or elevation more than 3000 m.a.s.l.), as inferred from the stable quality of modern analogues, principal components, and diversity of species and communities throughout the Holocene. For the eastern part of China, the proportion of fossil pollen spectra with good modern analogues increases from ca. 50% to ca. 80% during the last 2 millennia, indicating an enhanced intensity of anthropogenic disturbance on vegetation. This disturbance has caused the pollen spectra to become taxonomically less diverse over space (reduced abundances of arboreal taxa and increased abundances of herbaceous taxa), highlighting a reduced south-north differentiation and divergence from past vegetation between regions in the eastern part of China. We recommend that care is taken in eastern China when basing the development of ecosystem management strategies on vegetation changes in the region during the last 2000 years, since humans have significantly disturbed the vegetation during this period.


Asunto(s)
Ecosistema , Plantas , China , Actividades Humanas , Humanos , Polen , Árboles
16.
Virol J ; 18(1): 106, 2021 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-34059082

RESUMEN

BACKGROUND: In China, an HIV-infected man (complainant; P2) alleged that another man (defendant; P1) had unlawfully infected him with HIV through unprotected homosexual contact in 2018. METHODS: We employed epidemiological, serological and phylogenetic analyses to investigate the transmission linkage between two men who have sex with men (MSM). Partial segments of three HIV-1 gene regions (gag, pol, and env) were amplified and sequenced by cloning. Maximum-likelihood (ML) and Bayesian methods were used to determine the direction and estimate the timing of transmission. Local control sequences and database control sequences were also used in the phylogenetic analysis. RESULTS: It indicated that P2 underwent HIV seroconversion after P1 was diagnosed as HIV positive. The time to the most recent common ancestor (tMRCA) estimates consistently showed that P1 most likely became HIV-1 infected at an earlier date than P2. P1 and P2 were infected with the same HIV-1 CRF01_AE subtype according to segments of all three gene regions (gag, pol, and env). All three genetic regions of P1 have been subject to more potential selective forces than those of P2, indicating a longer evolutionary history. Bayesian and ML trees showed similar paraphyletic-monophyletic topologies of gag and env, with the virus from P1 located at the root, which supported a P1-to-P2 transmission direction. CONCLUSIONS: Phylogenetic investigations can elucidate HIV transmission linkage and might empower its use in the opposition of the intentional transmission of HIV-1 as a forensic tool.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Minorías Sexuales y de Género , Teorema de Bayes , Infecciones por VIH/transmisión , VIH-1/genética , Homosexualidad Masculina , Humanos , Masculino , Filogenia
17.
J Anim Ecol ; 90(6): 1444-1454, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33666227

RESUMEN

Food webs capture the trophic relationships and energy fluxes between species, which has fundamental impacts on ecosystem functioning and stability. Within a food web, the energy flux distribution between a predator and its prey species is shaped by food quantity-quality trade-offs and the contiguity of foraging. But the distribution of energy fluxes among prey species as well as its drivers and implications remain unclear. Here we used 157 aquatic food webs, which contain explicit energy flux information, to examine whether a predator's foraging is asymmetric and biased towards lower or higher trophic levels, and how these patterns may change with trophic level. We also evaluate how traditional topology-based approaches may over- or under-estimate a predator's trophic level and omnivory by ignoring the asymmetric foraging patterns. Our results demonstrated the prevalence of asymmetric foraging in natural aquatic food webs. Although predators prefer prey at higher trophic levels with potentially higher food quality, they obtain their energy mostly from lower trophic levels with a higher food quantity. Both tendencies, that is, stronger feeding preference for prey at higher trophic levels and stronger energetic reliance on prey at lower trophic levels are alleviated for predators at higher trophic levels. The asymmetric foraging lowers trophic levels and omnivory at both species and food web levels, compared to estimates from traditional topology-based approaches. Such overestimations by topology-based approaches are most pronounced for predators at lower trophic levels and communities with higher number of trophic species. Our study highlights the importance of energy flux information in understanding the foraging behaviour of predators as well as the structural complexity of natural food webs. The increasing availability of flux-based food web data will thus provide new opportunities to reconcile food web structure, functioning and stability.


Asunto(s)
Ecosistema , Cadena Alimentaria , Animales , Conducta Predatoria
18.
Acta Pharmacol Sin ; 42(1): 115-119, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32404981

RESUMEN

Acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as erlotinib, remains a major challenge in the targeted therapy of non-small cell lung cancer (NSCLC). HKB99 is a novel allosteric inhibitor of phosphoglycerate mutase 1 (PGAM1) that preferentially suppresses cell proliferation and induces more apoptosis in acquired erlotinib-resistant HCC827ER cells compared with its parental HCC827 cells. In this study we identified the molecular biomarkers for HKB99 response in erlotinib-resistant HCC827ER cells. We showed that HCC827ER cells displayed enhanced invasive pseudopodia structures as well as downregulated plasminogen activator inhibitor-2 (PAI-2). Meanwhile, PAI-2 knockdown by siPAI-2 candidates decreased the sensitivity of HCC827 parental cells to erlotinib. Moreover, HKB99 (5 µM) preferentially inhibited the invasive pseudopodia formation and increased the level of PAI-2 in HCC827ER cells. Collectively, this study provides new insight into the role of PAI-2 in regulating the sensitivity of erlotinib resistant NSCLC cells to PGAM1 inhibitor. Furthermore, PAI-2 level might be considered as a potential biomarker for predicting the efficacy of the PGAM1 allosteric inhibitor on the erlotinib resistant NSCLC cells.


Asunto(s)
Antracenos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Fosfoglicerato Mutasa/antagonistas & inhibidores , Sulfonamidas/farmacología , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Clorhidrato de Erlotinib/farmacología , Técnicas de Silenciamiento del Gen , Humanos , Neoplasias Pulmonares/metabolismo , Fosfoglicerato Mutasa/genética , Seudópodos/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
19.
Can J Infect Dis Med Microbiol ; 2021: 8518189, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34777671

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) is a disease caused by infection with the SFTS virus (SFTSV). SFTS has become a crucial public health concern because of the heavy burden, lack of vaccines, effective therapies, and high-fatality rate. Evidence suggests that SFTSV circulates between ticks and animals in nature and is transmitted to humans by tick bites. In particular, ticks have been implicated as vectors of SFTSV, where domestic or wild animals may play as the amplifying hosts. Many studies have identified antigens and antibodies against SFTSV in various animals such as sheep, goats, cattle, and rodents. Besides, person-to-person transmission through contact with blood or mucous of an infected person has also been reported. In this study, we reviewed the literature and summarized the vectors and hosts associated with SFTS and the possible risk factors.

20.
Angew Chem Int Ed Engl ; 58(40): 14197-14201, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31385423

RESUMEN

Bimetal-S-O composites have been rarely researched in electrochemical reduction of CO2 . Now, an amorphous Ag-Bi-S-O decorated Bi0 catalyst derived from Ag0.95 BiS0.75 O3.1 nanorods by electrochemical pre-treatment was used for catalyzing eCO2 RR, which exhibited a formate FE of 94.3 % with a formate partial current density of 12.52 mA cm-2 at an overpotential of only 450 mV. This superior performance was attributed to the attached amorphous Ag-Bi-S-O substance. S could be retained in the amorphous region after electrochemical pre-treatment only in samples derived from metal-S-O composites, and it would greatly enhance the formate selectivity by accelerating the dissociation of H2 O. The existence of Ag would increase the current density, resulting in a higher local pH, which made the role of S in activating H2 O more significantly and suppressed H2 evolution more effectively, thus endowing the catalyst with a higher formate FE at low overpotentials.

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