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1.
Nature ; 629(8013): 810-818, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38778234

RESUMO

Accurate and continuous monitoring of cerebral blood flow is valuable for clinical neurocritical care and fundamental neurovascular research. Transcranial Doppler (TCD) ultrasonography is a widely used non-invasive method for evaluating cerebral blood flow1, but the conventional rigid design severely limits the measurement accuracy of the complex three-dimensional (3D) vascular networks and the practicality for prolonged recording2. Here we report a conformal ultrasound patch for hands-free volumetric imaging and continuous monitoring of cerebral blood flow. The 2 MHz ultrasound waves reduce the attenuation and phase aberration caused by the skull, and the copper mesh shielding layer provides conformal contact to the skin while improving the signal-to-noise ratio by 5 dB. Ultrafast ultrasound imaging based on diverging waves can accurately render the circle of Willis in 3D and minimize human errors during examinations. Focused ultrasound waves allow the recording of blood flow spectra at selected locations continuously. The high accuracy of the conformal ultrasound patch was confirmed in comparison with a conventional TCD probe on 36 participants, showing a mean difference and standard deviation of difference as -1.51 ± 4.34 cm s-1, -0.84 ± 3.06 cm s-1 and -0.50 ± 2.55 cm s-1 for peak systolic velocity, mean flow velocity, and end diastolic velocity, respectively. The measurement success rate was 70.6%, compared with 75.3% for a conventional TCD probe. Furthermore, we demonstrate continuous blood flow spectra during different interventions and identify cascades of intracranial B waves during drowsiness within 4 h of recording.


Assuntos
Velocidade do Fluxo Sanguíneo , Encéfalo , Circulação Cerebrovascular , Ultrassonografia , Humanos , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Erros Médicos , Razão Sinal-Ruído , Pele , Crânio , Sonolência/fisiologia , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Adulto
2.
PLoS Biol ; 20(8): e3001707, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36040953

RESUMO

Hunting and its impacts on wildlife are typically studied regionally, with a particular focus on the Global South. Hunting can, however, also undermine rewilding efforts or threaten wildlife in the Global North. Little is known about how hunting manifests under varying socioeconomic and ecological contexts across the Global South and North. Herein, we examined differences and commonalities in hunting characteristics across an exemplary Global South-North gradient approximated by the Human Development Index (HDI) using face-to-face interviews with 114 protected area (PA) managers in 25 African and European countries. Generally, we observed that hunting ranges from the illegal, economically motivated, and unsustainable hunting of herbivores in the South to the legal, socially and ecologically motivated hunting of ungulates within parks and the illegal hunting of mainly predators outside parks in the North. Commonalities across this Africa-Europe South-North gradient included increased conflict-related killings in human-dominated landscapes and decreased illegal hunting with beneficial community conditions, such as mutual trust resulting from community involvement in PA management. Nevertheless, local conditions cannot outweigh the strong effect of the HDI on unsustainable hunting. Our findings highlight regional challenges that require collaborative, integrative efforts in wildlife conservation across actors, while identified commonalities may outline universal mechanisms for achieving this goal.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , África , Animais , Europa (Continente) , Humanos , Caça , Mamíferos
3.
Opt Lett ; 49(9): 2421-2424, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691734

RESUMO

We report on an optical amplification and energy threshold of the two most prominent emission lines, 391.4 and 427.8 nm, of the cavity-less lasing of nitrogen ions pumped by femtosecond laser pulses. It was found that the two transitions both show optical amplification under a low gas pressure condition, while the 391.4 nm emission is barely amplified under high gas pressure. Moreover, the 427.8 nm emission presents a significant lower pump laser energy threshold and a larger gain factor than the 391.4 nm emission. Numerical simulations based on a three-state coupling model suggest that the smaller ionization Franck-Condon factor from the ground state of N2 to the vibrational level ν = 1 in X 2 Σ g+ state of N2 + favors the formation of population inversion corresponding to the 427.8 nm emission. Meanwhile, the competition between the strong field ionization and excitation induced by the pumping laser requires higher laser intensity to acquire the population inversion for the 391.4 nm radiation, leading to a corresponding larger energy threshold.

4.
Molecules ; 28(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38067579

RESUMO

Koninginins X-Z (1-3), three novel polyketides, were isolated from the solid fermentation of the endophytic fungus Trichoderma koningiopsis SC-5. Their structures, including the absolute configurations, were comprehensively characterized by a combination of NMR spectroscopic methods, HRESIMS, 13C NMR, DFT GIAO 13C NMR, and electronic circular dichroism calculations as well as single crystal X-ray diffraction. In addition, all the compounds were evaluated for antifungal activity against Candida albicans.


Assuntos
Policetídeos , Trichoderma , Policetídeos/química , Estrutura Molecular , Trichoderma/química , Antifúngicos/química
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(4): 666-671, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37654147

RESUMO

Uric acid (UA) is the final product of purine metabolism in human body,and its metabolic disorder will induce hyperuricemia (HUA).The occurrence and development of HUA are associated with a variety of pathological mechanisms such as oxidative stress injury,activation of inflammatory cytokines,and activation of renin-angiotensin-aldosterone system.These mechanisms directly or indirectly affect the bioavailability of endogenous nitric oxide (NO).The decrease in NO bioavailability is common in the diseases with high concentration of UA as an independent risk factor.In this review,we summarize the mechanisms by which high concentrations of UA affect the endogenous NO bioavailability,with a focus on the mechanisms of high-concentration UA in decreasing the synthesis and/or increasing the consumption of NO.This review aims to provide references for alleviating the multisystem symptoms and improving the prognosis of HUA,and lay a theoretical foundation for in-depth study of the correlations between HUA and other metabolic diseases.


Assuntos
Hiperuricemia , Óxido Nítrico , Humanos , Ácido Úrico , Disponibilidade Biológica , Citocinas
6.
J Chem Phys ; 154(23): 234703, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34241242

RESUMO

A single atom Ti-Cu(111) surface alloy can be generated by depositing small amounts of Ti onto Cu(111) at slightly elevated surface temperatures (∼500 to 600 K). Scanning tunneling microscopy shows that small Ti-rich islands covered by a Cu single layer form preferentially on ascending step edges of Cu(111) during Ti deposition below about 400 K but that a Ti-Cu(111) alloy replaces these small islands during deposition between 500 and 600 K, producing an alloy in the brims of the steps. Larger partially Cu-covered Ti-containing islands also form on the Cu(111) terraces at temperatures between 300 and 700 K. After surface exposure to CO at low temperatures, reflection absorption infrared spectroscopy (RAIRS) reveals distinct C-O stretch bands at 2102 and 2050 cm-1 attributed to CO adsorbed on Cu-covered Ti-containing domains vs sites in the Ti-Cu(111) surface alloy. Calculations using density functional theory (DFT) suggest that the lower frequency C-O stretch band originates specifically from CO adsorbed on isolated Ti atoms in the Ti-Cu(111) surface alloy and predicts a higher C-O stretch frequency for CO adsorbed on Cu above subsurface Ti ensembles. DFT further predicts that CO preferentially adsorbs in flat-lying configurations on contiguous Ti surface structures with more than one Ti atom and thus that CO adsorbed on such structures should not be observed with RAIRS. The ability to generate a single atom Ti-Cu(111) alloy will provide future opportunities to investigate the surface chemistry promoted by a representative early transition metal dopant on a Cu(111) host surface.

7.
Proc Natl Acad Sci U S A ; 115(9): 2084-2089, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29440424

RESUMO

Protected areas (PAs) remain the dominant policy to protect biodiversity and ecosystem services but have been shown to have limited impact when development interests force them to locations with lower deforestation pressure. Far less known is that such interests also cause widespread tempering, reduction, or removal of protection [i.e., PA downgrading, downsizing, and degazettement (PADDD)]. We inform responses to PADDD by proposing and testing a bargaining explanation for PADDD risks and deforestation impacts. We examine recent degazettements for hydropower development and rural settlements in the state of Rondônia in the Brazilian Amazon. Results support two hypotheses: (i) ineffective PAs (i.e., those where internal deforestation was similar to nearby rates) were more likely to be degazetted and (ii) degazettement of ineffective PAs caused limited, if any, additional deforestation. We also report on cases in which ineffective portions were upgraded. Overall our results suggest that enhancing PAs' ecological impacts enhances their legal durability.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Biodiversidade , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Agricultura Florestal , Órgãos Governamentais , Humanos , Fatores de Risco
8.
Ecotoxicol Environ Saf ; 208: 111688, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396020

RESUMO

Elemental defense hypothesis suggests that toxic metals accumulated in plant tissues could enhance plant defense against herbivores and pathogens. Since over-accumulation of metals in plant organs will pose negative effects on plant health, it is necessary to find a way to alleviate metal-induced toxicity in plants while keeping or even improving plant resistance. Exogenous nitrogen (N) application was reported to have such alleviation effect while stimulating metal accumulation in plant tissues. In this study, we examined whether soil N addition in three different doses to a poplar species under cadmium (Cd) stress can simultaneously improve plant growth and resistance to four herbivorous insects and a leaf pathogen. The results showed that N application to Cd-amended soil prominently enhanced plant growth and leaf Cd accumulation. While N addition in three doses all remarkably reduced herbivore growth than control plants, only the highest N dose exerted stronger inhibition than the sole Cd-treated plants. In the paired-choice experiment, plants supplied with the highest N dose showed an enhanced deterrent effect on herbivore preference than plants exposed to sole Cd. Furthermore, plant resistance to the leaf pathogen infection was strongly enhanced as the levels of N addition increased. Leaf sugar and three main defensive chemicals were not affected by N application implied that such enhanced effect of N on plant resistance was due to increased leaf Cd accumulation. Our results suggested that the application of exogenous N over a certain amount could enhance the resistance of Cd-treated plants to leaf herbivory and pathogen infection.


Assuntos
Cádmio/toxicidade , Nitrogênio/farmacologia , Folhas de Planta/efeitos dos fármacos , Populus/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Cádmio/metabolismo , Herbivoria/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , Pestalotiopsis/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Populus/crescimento & desenvolvimento , Populus/microbiologia , Solo/química , Poluentes do Solo/metabolismo
9.
J Environ Manage ; 288: 112467, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33823455

RESUMO

Elemental defense hypothesis (EDH) proposed that metal accumulation in plants could increase plant resistance to herbivores. However, the over-accumulation of metals in low-accumulators such as woody plants will cause adverse effects on plant health. Thus, the application of EDH on low-accumulators in metal contaminated areas is strongly limited. Since the supplement of exogenous spermidine (Spd) was reported to alleviate metal-induced toxicity in plants while stimulating metal accumulation in plant tissues, we hypothesized that such application will further improve plant resistance to herbivores. In this study, we employed a woody plant species, Populus yunnanensis, to test this hypothesis. We first tested a Spd concentration series applied on plants subjected to soil cadmium (Cd) stress and found that the 1 mM Spd strongly promoted plant growth while stimulated Cd accumulation in plant leaves and roots. We further conducted herbivore bioassays to test the growth performance and feeding preference of two leaf herbivore species and a root herbivore species that fed on plants from different treatments. The results showed that the inhibition effect of Cd stressed-plants on herbivore growth was significantly magnified by the addition of Spd. The growth weight of all the three tested herbivores were negatively correlated with increased Cd concentrations in plant tissues. In addition, the feeding preferences of the two leaf herbivore species were strongly repelled by leaf discs from Cd-treated plants with Spd supplement. The results suggested that the application of exogenous Spd at a certain dose could enhance elemental defense of plants against herbivory.


Assuntos
Cádmio , Populus , Cádmio/toxicidade , Herbivoria , Folhas de Planta , Solo , Espermidina
10.
Conserv Biol ; 33(6): 1275-1285, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31192510

RESUMO

Protected areas (PAs) are expected to conserve nature and provide ecosystem services in perpetuity, yet widespread protected area downgrading, downsizing, and degazettement (PADDD) may compromise these objectives. Even iconic protected areas are vulnerable to PADDD, although these PADDD events are often unrecognized. We identified 23 enacted and proposed PADDD events within World Natural Heritage Sites and examined the history, context, and consequences of PADDD events in 4 iconic PAs (Yosemite National Park, Arabian Oryx Sanctuary, Yasuní National Park, and Virunga National Park). Based on insights from published research and international workshops, these 4 cases revealed the diverse pressures brought on by competing interests to develop or exploit natural landscapes and the variety of mechanisms that enables PADDD. Knowledge gaps exist in understanding of the conditions through which development pressures translate to PADDD events and their impacts, partially due to a lack of comprehensive PADDD records. Future research priorities should include comprehensive regional and country-level profiles and analysis of risks, impacts, and contextual factors related to PADDD. Policy options to better govern PADDD include improving tracking and reporting of PADDD events, establishing transparent PADDD policy processes, coordinating among legal frameworks, and mitigating negative impacts of PADDD. To support PADDD research and policy reforms, enhanced human and financial capacities are needed to train local researchers and to host publicly accessible data. As the conservation community considers the achievements of Aichi Target 11 and moves toward new biodiversity targets beyond 2020, researchers, practitioners, and policy makers need to work together to better track, assess, and govern PADDD globally.


Cambios de Categoría, Reducción del Tamaño y Eliminación de las Listas de Protección como Amenazas para las Áreas Protegidas Icónicas Resumen Se espera que las áreas protegidas (PAs, en inglés) conserven la naturaleza y proporcionen servicios ambientales a perpetuidad, sin embargo las extensas prácticas de reducción del tamaño, eliminación de las listas de protección y cambios de categoría de las áreas protegidas (PADDD, en inglés) pueden poner en riesgo a estos objetivos. Incluso las áreas protegidas icónicas son vulnerables a los PADDD, aunque estos eventos de PADDD comúnmente no se reconocen. Identificamos 23 eventos de PADDDD promulgados y propuestos dentro de sitios de Patrimonio Natural Mundial y examinamos la historia, el contexto y las consecuencias de los eventos PADDD en cuatro PAs icónicas (el Parque Nacional Yosemite, el Santuario del Oryx Árabe, el Parque Nacional Yasuní y el Parque Nacional Virunga). Con base en el conocimiento obtenido de investigaciones publicadas y talleres internacionales, estos cuatro casos revelaron las diferentes presiones que traen consigo los intereses en competencia por desarrollar o explotar los paisajes naturales y la variedad de mecanismos que faciliten las PADDD. Existen vacíos de conocimiento en el entendimiento de las condiciones a través de las cuales las presiones del desarrollo se transforman en eventos PADDD y los impactos que tienen, parcialmente debido a la falta de registros completos de los eventos PADDD. Las prioridades de las próximas investigaciones deberían incluir perfiles completos a nivel regional y nacional y un análisis de riesgo, impactos y factores contextuales relacionados con los PADDD. Las opciones políticas para gobernar de mejor manera los PADDD incluyen la mejora del rastreo y del reporte de eventos PADDD, el establecimiento de procesos políticos transparentes para los PADDD, la coordinación entre los marcos de trabajo legales y la mitigación de los impactos negativos de los PADDD. Para apoyar la investigación de los PADDD y las reformas políticas se requiere de una mayor capacidad humana y financiera para entrenar a los investigadores locales y para acoger datos accesibles para el público. Conforme la comunidad de la conservación considera los logros del Objetivo 11 de Aichi y se posiciona hacia nuevos objetivos para la biodiversidad más allá del 2020, los investigadores, los practicantes y los legisladores necesitan trabajar en conjunto para rastrear, evaluar y gobernar de mejor manera los PADDD a nivel mundial.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Humanos , Parques Recreativos , Políticas
12.
Acad Radiol ; 31(4): 1508-1517, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37923575

RESUMO

RATIONALE AND OBJECTIVES: To analyse the MRI-based radiomics and delta-radiomics features to establish radiomics models for predicting the radiographic progression of osteoarthritis (OA). MATERIALS AND METHODS: The data used in this research come from the dataset of the FNIH Biomarker Consortium Project within the Osteoarthritis Initiative (OAI). 565 participants randomly divided into training and validation groups at a 7:3 ratio. The training cohort consisted of 395 participants and included 202 cases. The validation cohort consisted of 170 participants and included 87 cases. Least absolute shrinkage and selection operator (LASSO) was used for feature selection. Support vector machine (SVM) was used to establish radiomics models and clinical and biomarker models for predicting the radiographic progression of OA. The predictive ability of the model was evaluated by the area under the curve (AUC). RESULTS: The baseline, 24 M, Delta, and two combination radiomics models (Baseline and Delta, 24 M and Delta) all showed good predictive performance in the training and validation cohorts, with the combination model exhibiting the best performance. In the training cohort, the AUCs were 0.851 (95% CI: 0.812-0.890), 0.825 (95% CI: 0.784-0.865), 0.804 (95% CI: 0.761-0.847), 0.892 (95% CI: 0.860-0.924) and 0.884 (95% CI: 0.851-0.917), respectively. The AUCs in the validation cohort were 0.741 (95% CI: 0.667-0.814), 0.786 (95% CI: 0.716-0.856), 0.745 (95% CI: 0.671-0.819), 0.781 (95% CI: 0.711-0.851) and 0.802 (95% CI: 0.736-0.869), respectively. As compared, the clinical and biomarker models have AUC < 0.74. The DeLong test showed that the predictive performance of the radiomics models in the training and validation cohorts was significantly better than that of the clinical and biomarker models (P < 0.001). CONCLUSION: The MRI-based radiomics models of the patella all showed good predictive performance performed better than the clinical and biomarker models in predicting the radiographic progression of OA. Delta radiomics can improve the predictive performance of the single time model, the combined model of 24 M and Delta provided the best predictive performance.


Assuntos
Osteoartrite , Patela , Humanos , Radiômica , Biomarcadores , Imageamento por Ressonância Magnética , Osteoartrite/diagnóstico por imagem , Estudos Retrospectivos
13.
Nat Prod Res ; : 1-9, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767208

RESUMO

A new lignan phyllanins A (1) and a lignan phyllanins B (2) for which the absolute configuration was determined for the first time, along with four known lignans (3-6) were isolated from the branch and leaf extracts of Phyllanthodendron dunnianum. Their planar structures were mainly determined by a combination of 1D and 2D NMR, HRESIMS spectral analyses, and the absolute configurations of the compounds 1 and 2 were established by DFT GIAO 13C NMR and electronic circular dichroism (ECD) calculations. In addition, all these six lignans were firstly tested for the antibacterial activities against MRSA, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli. Among these compounds, 2 and 5 showed potential antibacterial activities against MRSA and S. aureus with MIC values of 4 and 8 µg/mL, respectively.

14.
J Clin Anesth ; 92: 111286, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37837796

RESUMO

STUDY OBJECTIVE: Most laparoscopic surgeries under general anesthesia are performed in noisy environments, although the effect of intraoperative noise reduction on postoperative pain remains uncertain. This study aimed to explore whether postoperative pain could be reduced through the intraoperative use of noise-cancelling headphones. DESIGN: This study was conducted as a prospective parallel-group randomized clinical trial. SETTING: Operating room and surgery room. PATIENTS: Ninety patients who underwent laparoscopic surgery under general anesthesia. INTERVENTIONS: In the intervention group, noise-cancelling headphones were used to reduce noise intensity during laparoscopic surgery under general anesthesia. MEASUREMENTS: The primary outcome was the maximum movement-evoked pain intensity within 24 h post-surgery, measured using a 10-point numeric rating scale. Secondary outcomes included the maximum resting pain score and total opioid consumption during the 24-h period post-surgery. Mean intraoperative noise and the proportion of intraoperative time with noise intensity ≥70 dB were recorded. MAIN RESULTS: The maximum movement-evoked pain score was significantly lower in the intervention group than in the control group (mean score [SD], 2.7 [1.0] and 4.0[1.0], respectively; P < 0.001). The intervention group required significantly fewer opioids than the control group (mean [SD], 44.2 [12.8] and 51.3[17.5] mg, respectively; P = 0.032). In the control group, but not the intervention group, all postoperative pain scores were significantly associated with the proportion of intraoperative time with noise intensity ≥70 dB, which was an independent risk factor for postoperative pain. CONCLUSION: During laparoscopic surgery under general anesthesia, intraoperative noise isolation using noise-cancelling headphones is a safe and effective strategy for relieving postoperative pain and decreasing total opioid analgesic consumption.


Assuntos
Laparoscopia , Dor Pós-Operatória , Humanos , Estudos Prospectivos , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Laparoscopia/efeitos adversos , Analgésicos Opioides/uso terapêutico , Anestesia Geral/efeitos adversos
15.
Fitoterapia ; 173: 105809, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168565

RESUMO

Three new indole diketopiperazines, ochrolines A-C (1-3), along with three known compounds (4-6), were isolated and identified from the EtOAc extract of the solid fermentation of Bionectria ochroleuca SLJB-2. Notably, compound 1 featured a natural rarely-occurring caged skeleton with a 6/5/6/7 heterotetracyclic bridged ring system. The structures including absolute configurations of 1-3 were fully accomplished by extensive spectroscopic analyses, DFT GIAO 13C NMR and electronic circular dichroism (ECD) calculations. The plausible biogenetic pathways of these new indole diketopiperazines were also proposed. Moreover, the cytotoxic activity screening revealed that compound 2 exhibited moderate inhibitory effect against A549 with inhibition rate of 57.44% at the concentration of 50 µM and compound 1 exhibited mild inhibitory activities against A549, Hela and MCF-7.


Assuntos
Dicetopiperazinas , Hypocreales , Dicetopiperazinas/química , Estrutura Molecular , Fungos , Hypocreales/química , Indóis/farmacologia
16.
Nat Prod Bioprospect ; 14(1): 8, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206497

RESUMO

Two novel koninginin derivatives, koningipyridines A and B (1 and 2), along with four known compounds (3-6) were isolated from the EtOAc extract of the endophytic fungus Trichoderma koningiopsis SC-5. Among them, koningipyridine A featured an unprecedented pentacyclic ketal skeleton with the formation of a fascinating 6/6/5/6/5 fused ring system and shared a characteristic pyridine core, which represents the first example of nitrogen-containing koninginin-type natural product. Moreover, koningipyridine B was the first member in the koninginin family sharing a unique 6/6/5 dihydropyridine skeleton, and it was suggested to be the critical biosynthetic precursor of koningipyridine A. The structures of 1 and 2 were elucidated by the interpretation of 1D and 2D NMR spectroscopy, HRESIMS data, as well as theoretical calculations of 13C NMR and electronic circular dichroism (ECD). Moreover, all isolates were screened for antimicrobial activities against Staphylococcus aureus, MRSA, and Escherichia coli as well as the cytotoxic effects against three cancer cell lines (A549, Hela, and HepG2).

17.
R Soc Open Sci ; 11(7): 240295, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39021768

RESUMO

Land-use expansion is linked to major sustainability concerns including climate change, food security and biodiversity loss. This expansion is largely concentrated in so-called 'frontiers', defined here as places experiencing marked transformations owing to rapid resource exploitation. Understanding the mechanisms shaping these frontiers is crucial for sustainability. Previous work focused mainly on explaining how active frontiers advance, in particular, into tropical forests. Comparatively, our understanding of how frontiers emerge in territories considered marginal in terms of agricultural productivity and global market integration remains weak. We synthesize conceptual tools explaining resource and land-use frontiers, including theories of land rent and agglomeration economies, of frontiers as successive waves, spaces of territorialization, friction and opportunities, anticipation and expectation. We then propose a new theory of frontier emergence, which identifies exogenous pushes, legacies of past waves and actors' anticipations as key mechanisms by which frontiers emerge. Processes of differential rent creation and capture and the built-up of agglomeration economies then constitute key mechanisms sustaining active frontiers. Finally, we discuss five implications for the governance of frontiers for sustainability. Our theory focuses on agriculture and deforestation frontiers in the tropics but can be inspirational for other frontier processes including for extractive resources, such as minerals.

18.
Dev Comp Immunol ; 146: 104736, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37207976

RESUMO

BmTsp.A (Bombyx mori Tetraspanin A) is one of the four transmembrane proteins which are capable to regulate multiple aspects of the immune response and are involved in various stages of viral invasion of the hosts. This study focused on the sequence features, analysis of expression pattern, as well as the effect of BmTsp.A on BmNPV (Bombyx mori nucleopolyhedrovirus) infection in the apoptotic pathway. BmTsp.A features the typical tetraspanins family, including four transmembrane domains and a major large extracellular loop domain. It is highly expressed specifically in the malpighian tubes, and its expression is increased by BmNPV induction for 48 h and 72 h. Overexpression and RNAi (RNA interference) mediated by siRNA reveal that BmTsp.A can promote the infection and replication of the virus. In addition, the overexpression of BmTsp.A regulates BmNPV-induced apoptosis, leading to changes in the expression of apoptosis-related genes and thus affecting viral proliferation. When subjected to stimulation by BmNPV infection, on the one hand, BmTsp.A inhibits Bmp53 through a Caspase-dependent pathway, which consequently promotes the expression of Bmbuffy, thereby activating BmICE to inhibit apoptosis and causing the promotion of viral proliferation. On the other hand, BmTsp.A inhibits the expression of BmPTEN and BmPkc through the phosphatidylinositol 3 kinase (PI3K)/protein kinaseB(AKT) signaling pathway, thus affecting the regulation of apoptosis. To summarize, our results demonstrate that BmTsp.A promotes viral infection and replication by inhibiting apoptosis, which is fundamental for understanding the pathogenesis of BmNPV and the immune defense mechanism of silkworm.


Assuntos
Bombyx , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Insetos/metabolismo , Apoptose , Tetraspaninas/genética , Tetraspaninas/metabolismo
19.
Int J Surg ; 109(12): 3872-3882, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37598384

RESUMO

BACKGROUND: Most patients are in a noisy environment during abdominal surgery under general anesthesia. This study included patients who underwent abdominal surgery under general anesthesia and established an animal model to determine whether intraoperative noise affects postoperative pain. MATERIALS AND METHODS: This prospective study included 200 patients who underwent abdominal surgery under general anesthesia. Intraoperative noise and electroencephalograms were continuously recorded, and the mean level and time proportion of noise intensity of greater than 70 dB were calculated. Maximum postoperative pain was assessed using a numerical rating scale at 0-12 h and 12-24 h after surgery, and postoperative analgesia consumption in patients receiving patient-controlled intravenous analgesia was recorded. Postoperative pain intensity and electroencephalogram amplitude were compared between patients with high-noise exposure (time proportion of noise intensity greater than 70 dB ≥40%) and low-noise exposure (<40%). Mechanical pain sensitivity was tested in two groups of mice with plantar incisions exposed to 40 dB or 70-100 dB. RESULTS: The time proportion of noise intensity greater than 70 dB was identified as an independent risk factor for postoperative pain intensity ( P <0.001). P ain numerical rating scale 0-12 h (4.5±1.5 vs. 3.7±1.3, P =0.001) and 12-24 h (3.9±1.5 vs. 3.2±1.1, P =0.004) after surgery in patients with high-noise exposure was significantly higher than in patients with low-noise exposure. The electroencephalogram amplitude of patients with high-noise exposure was significantly lower than that of patients with low-noise exposure ( P <0.05). In the mouse model, mechanical hyperalgesia in the 70-100 dB group was significantly greater than that in the 40 dB group ( P <0.001). CONCLUSION: High-level intraoperative noise exposure aggravates the degree of postoperative pain and analgesic needs of patients undergoing abdominal surgery, which may be related to the impact of noise on the neurophysiological activity of the brain and postoperative hyperalgesia.


Assuntos
Analgésicos Opioides , Analgésicos , Humanos , Animais , Camundongos , Estudos Prospectivos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Anestesia Geral/efeitos adversos
20.
Nat Prod Res ; : 1-11, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37933750

RESUMO

One new cyclopeptide, cyclo-(L-Trp-L-Phe-L-Phe) (1), one new 2-pyridone derivative, fusarone A (3), and one new natural indole derivative, ethyl 3-indoleacetate (4), along with six known compounds were isolated from the endophytic fungus Fusarium proliferatum T2-10. The planar structures of three new compounds were identified by spectral methods including 1D and 2D NMR techniques, and the absolute configuration of compound 1 was elucidated by Marfey-MS method. In addition, all compounds were evaluated for their cytotoxic and antibacterial activities in vitro. Compound 2 showed remarkable cytotoxic activities against two human hepatoma cell lines SMMC7721 and HepG2 with IC50 values of 5.89 ± 0.74 and 6.16 ± 0.52 µM, and showed moderate antibacterial activities against Staphylococcus aureus and Enterococcus faecalis with MIC values of 7.81 and 15.62 µg/mL, respectively.

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