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1.
Nature ; 603(7900): 328-334, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35197632

RESUMEN

Effective antitumour immunity depends on the orchestration of potent T cell responses against malignancies1. Regression of human cancers has been induced by immune checkpoint inhibitors, T cell engagers or chimeric antigen receptor T cell therapies2-4. Although CD8 T cells function as key effectors of these responses, the role of CD4 T cells beyond their helper function has not been defined. Here we demonstrate that a trispecific antibody to HER2, CD3 and CD28 stimulates regression of breast cancers in a humanized mouse model through a mechanism involving CD4-dependent inhibition of tumour cell cycle progression. Although CD8 T cells directly mediated tumour lysis in vitro, CD4 T cells exerted antiproliferative effects by blocking cancer cell cycle progression at G1/S. Furthermore, when T cell subsets were adoptively transferred into a humanized breast cancer tumour mouse model, CD4 T cells alone inhibited HER2+ breast cancer growth in vivo. RNA microarray analysis revealed that CD4 T cells markedly decreased tumour cell cycle progression and proliferation, and also increased pro-inflammatory signalling pathways. Collectively, the trispecific antibody to HER2 induced T cell-dependent tumour regression through direct antitumour and indirect pro-inflammatory/immune effects driven by CD4 T cells.


Asunto(s)
Neoplasias de la Mama , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Antígenos CD28/metabolismo , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Femenino , Humanos , Ratones , Receptor ErbB-2/genética
2.
Proc Natl Acad Sci U S A ; 120(1): e2214874120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36574710

RESUMEN

Adequate mass and function of adipose tissues (ATs) play essential roles in preventing metabolic perturbations. The pathological reduction of ATs in lipodystrophy leads to an array of metabolic diseases. Understanding the underlying mechanisms may benefit the development of effective therapies. Several cellular processes, including autophagy and vesicle trafficking, function collectively to maintain AT homeostasis. Here, we investigated the impact of adipocyte-specific deletion of the lipid kinase phosphatidylinositol 3-kinase catalytic subunit type 3 (PIK3C3) on AT homeostasis and systemic metabolism in mice. We report that PIK3C3 functions in all ATs and that its absence disturbs adipocyte autophagy and hinders adipocyte differentiation, survival, and function with differential effects on brown and white ATs. These abnormalities cause loss of white ATs, whitening followed by loss of brown ATs, and impaired "browning" of white ATs. Consequently, mice exhibit compromised thermogenic capacity and develop dyslipidemia, hepatic steatosis, insulin resistance, and type 2 diabetes. While these effects of PIK3C3 largely contrast previous findings with the autophagy-related (ATG) protein ATG7 in adipocytes, mice with a combined deficiency in both factors reveal a dominant role of the PIK3C3-deficient phenotype. We have also found that dietary lipid excess exacerbates AT pathologies caused by PIK3C3 deficiency. Surprisingly, glucose tolerance is spared in adipocyte-specific PIK3C3-deficient mice, a phenotype that is more evident during dietary lipid excess. These findings reveal a crucial yet complex role for PIK3C3 in ATs, with potential therapeutic implications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Animales , Ratones , Fosfatidilinositol 3-Quinasas Clase III/genética , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Adipocitos/metabolismo , Lípidos , Tejido Adiposo Pardo/metabolismo , Adipocitos Marrones/metabolismo
3.
J Am Chem Soc ; 146(9): 5964-5976, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38381843

RESUMEN

Fluorinated ethers have become promising electrolyte solvent candidates for lithium metal batteries (LMBs) because they are endowed with high oxidative stability and high Coulombic efficiencies of lithium metal stripping/plating. Up to now, most reported fluorinated ether electrolytes are -CF3-based, and the influence of ion solvation in modifying degree of fluorination has not been well-elucidated. In this work, we synthesize a hexacyclic coordinated ether (1-methoxy-3-ethoxypropane, EMP) and its fluorinated ether counterparts with -CH2F (F1EMP), -CHF2 (F2EMP), or -CF3 (F3EMP) as terminal group. With lithium bis(fluorosulfonyl)imide as single salt, the solvation structure, Li-ion transport behavior, lithium deposition kinetics, and high-voltage stability of the electrolytes were systematically studied. Theoretical calculations and spectra reveal the gradually reduced solvating power from nonfluorinated EMP to fully fluorinated F3EMP, which leads to decreased ionic conductivity. In contrast, the weakly solvating fluorinated ethers possess higher Li+ transference number and exchange current density. Overall, partially fluorinated -CHF2 is demonstrated as the desired group. Further full cell testing using high-voltage (4.4 V) and high-loading (3.885 mAh cm-2) LiNi0.8Co0.1Mn0.1O2 cathode demonstrates that F2EMP electrolyte enables 80% capacity retention after 168 cycles under limited Li (50 µm) and lean electrolyte (5 mL Ah-1) conditions and 129 cycles under extremely lean electrolyte (1.8 mL Ah-1) and the anode-free conditions. This work deepens the fundamental understanding on the ion transport and interphase dynamics under various degrees of fluorination and provides a feasible approach toward the design of fluorinated ether electrolytes for practical high-voltage LMBs.

4.
Plant Biotechnol J ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923257

RESUMEN

Oil-Camellia (Camellia oleifera), belonging to the Theaceae family Camellia, is an important woody edible oil tree species. The Camellia oil in its mature seed kernels, mainly consists of more than 90% unsaturated fatty acids, tea polyphenols, flavonoids, squalene and other active substances, which is one of the best quality edible vegetable oils in the world. However, genetic research and molecular breeding on oil-Camellia are challenging due to its complex genetic background. Here, we successfully report a chromosome-scale genome assembly for a hexaploid oil-Camellia cultivar Changlin40. This assembly contains 8.80 Gb genomic sequences with scaffold N50 of 180.0 Mb and 45 pseudochromosomes comprising 15 homologous groups with three members each, which contain 135 868 genes with an average length of 3936 bp. Referring to the diploid genome, intragenomic and intergenomic comparisons of synteny indicate homologous chromosomal similarity and changes. Moreover, comparative and evolutionary analyses reveal three rounds of whole-genome duplication (WGD) events, as well as the possible diversification of hexaploid Changlin40 with diploid occurred approximately 9.06 million years ago (MYA). Furthermore, through the combination of genomics, transcriptomics and metabolomics approaches, a complex regulatory network was constructed and allows to identify potential key structural genes (SAD, FAD2 and FAD3) and transcription factors (AP2 and C2H2) that regulate the metabolism of Camellia oil, especially for unsaturated fatty acids biosynthesis. Overall, the genomic resource generated from this study has great potential to accelerate the research for the molecular biology and genetic improvement of hexaploid oil-Camellia, as well as to understand polyploid genome evolution.

5.
Appl Environ Microbiol ; 90(1): e0125023, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38112479

RESUMEN

Valorization of microalgae into high-value products and drop-in chemicals can reduce our dependence on non-renewable fossil fuels in an environmentally sustainable way. Among the valuable products, medium-chain carboxylic acids (MCCAs) and alcohols are attractive building blocks as fuel precursors. However, the biosynthetic mechanisms of MCCAs and alcohols in anaerobic microalgae fermentation and the regulating role of pH on the microbial structure and metabolism interaction among different functional groups have never been documented. In this work, we systematically investigated the roles of pH (5, 7, and 10) on the production of MCCAs and alcohols in anaerobic microalgae fermentation. The gene-centric and genome-centric metagenomes were employed to uncover the dynamics and metabolic network of the key players in the microbial communities. The results indicated that the pH significantly changed the product spectrum. The maximum production rate of alcohol was obtained at pH 5, while pH 7 was more beneficial for MCCA production. Metagenomic analysis reveals that this differential performance under different pH is attributed to the transformation of microbial guild and metabolism regulated by pH. The composition of various functional groups for MCCA and alcohol production also varies at different pH levels. Finally, a metabolic network was proposed to reveal the microbial interactions at different pH levels and thus provide insights into bioconversion of microalgae to high-value biofuels.IMPORTANCECarboxylate platforms encompass a biosynthesis process involving a mixed and undefined culture, enabling the conversion of microalgae, rich in carbohydrates and protein, into valuable fuels and mitigating the risks associated with algae blooms. However, there is little known about the effects of pH on the metabolic pathways of chain elongation and alcohol production in anaerobic microalgae fermentation. Moreover, convoluted and interdependent microbial interactions encumber efforts to characterize how organics and electrons flow among microbiome members. In this work, we compared metabolic differences among three different pH levels (5, 7, and 10) in anaerobic microalgae fermentation. In addition, genome-centric metagenomic analysis was conducted to reveal the microbial interaction for medium-chain carboxylic acid and alcohol production.


Asunto(s)
Ácidos Carboxílicos , Microalgas , Fermentación , Ácidos Carboxílicos/metabolismo , Microalgas/metabolismo , Anaerobiosis , Etanol/metabolismo , Concentración de Iones de Hidrógeno
6.
Opt Lett ; 49(11): 2974-2977, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824306

RESUMEN

Vertical couplers play a pivotal role as essential components supporting interconnections between fibers and photonic integrated circuits (PICs). In this study, we propose and demonstrate a high-performance perfectly vertical coupler based on a three-stage inverse design method, realized through a single full etching process on a 220-nm silicon-on-insulator (SOI) platform with a backside metal mirror. Under surface-normal fiber placement, experimental results indicate a remarkable 3-dB bandwidth of 99 nm with a peak coupling efficiency of -1.44 dB at the wavelength of 1549 nm. This achievement represents the best record to date, to the best of our knowledge, for a perfectly vertical coupler fabricated under similar process conditions.

7.
Mol Pharm ; 21(6): 2751-2766, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38693707

RESUMEN

Innate defense regulator-1002 (IDR-1002) is a synthetic peptide with promising immunomodulatory and antibiofilm properties. An appreciable body of work exists around its mechanism of action at the cellular and molecular level, along with its efficacy across several infection and inflammation models. However, little is known about its absorption, distribution, and excretion in live organisms. Here, we performed a comprehensive biodistribution assessment with a gallium-67 radiolabeled derivative of IDR-1002 using nuclear tracing techniques. Various dose levels of the radiotracer (2-40 mg/kg) were administered into the blood, peritoneal cavity, and subcutaneous tissue, or instilled into the lungs. The peptide was well tolerated at all subcutaneous and intraperitoneal doses, although higher levels were associated with delayed absorption kinetics and precipitation of the peptide within the tissues. Low intratracheal doses were rapidly absorbed systemically, and small increases in the dose level were lethal. Intravenous doses were rapidly cleared from the blood at lower levels, and upon escalation, were toxic with a high proportion of the dose accumulating within the lung tissue. To improve biocompatibility and prolong its circulation within the blood, IDR-1002 was further formulated onto high molecular weight hyperbranched polyglycerol (HPG) polymers. Constructs prepared at 5:1 and 10:1 peptide-to-polymer ratios were colloidally stable, maintained the biological profile of the peptide payload and helped reduce red blood cell lysis. The 5:1 construct circulated well in the blood, but higher peptide loading was associated with rapid clearance by the reticuloendothelial system. Many peptides face pharmacokinetic and biocompatibility challenges, but formulations such as those with HPG have the potential to overcome these limitations.


Asunto(s)
Radioisótopos de Galio , Animales , Distribución Tisular , Ratones , Radioisótopos de Galio/farmacocinética , Radioisótopos de Galio/química , Radioisótopos de Galio/administración & dosificación , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Péptidos/química , Péptidos/farmacocinética , Femenino , Nanopartículas/química , Ratones Endogámicos C57BL , Masculino , Inmunidad Innata/efectos de los fármacos , Péptidos Catiónicos Antimicrobianos/farmacocinética , Péptidos Catiónicos Antimicrobianos/química
8.
Environ Sci Technol ; 58(28): 12520-12531, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38953238

RESUMEN

Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.


Asunto(s)
Fermentación , Aguas del Alcantarillado , Biotecnología/métodos , Ácidos Grasos/metabolismo
9.
J Immunol ; 209(2): 199-207, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35821102

RESUMEN

Lymphocytes can be functionally partitioned into subsets belonging to the innate or adaptive arms of the immune system. Subsets of innate and innate-like lymphocytes may or may not express Ag-specific receptors of the adaptive immune system, yet they are poised to respond with innate-like speed to pathogenic insults but lack the capacity to develop classical immunological memory. These lymphocyte subsets display a number of common properties that permit them to integrate danger and stress signals dispatched by innate sensor cells to facilitate the generation of specialized effector immune responses tailored toward specific pathogens or other insults. In this review, we discuss the functions of distinct subsets of innate and innate-like lymphocytes. A better understanding of the mechanisms by which these cells are activated in different contexts, their interactions with other immune cells, and their role in health and disease may inform the development of new or improved immunotherapies.


Asunto(s)
Inmunidad Innata , Linfocitos , Memoria Inmunológica , Inmunoterapia
10.
Bioorg Chem ; 144: 107175, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38335757

RESUMEN

Eight undescribed (1-8) and 46 known compounds (9-54) were isolated from the deep-sea-derived Aspergillus sp. MCCC 3A00392. Compounds 1-3 were three novel oxoindolo diterpenoids, 4-6 were three bisabolane sesquiterpenoids, while 7 and 8 were two monocyclic cyclopropanes. Their structures were established by exhaustive analyses of the HRESIMS, NMR, and theoretical calculations of the NMR data and ECD spectra. Compounds 10, 33, 38, and 39 were able to inhibit tumor necrosis factor (TNF)-induced necroptosis in murine L929 cell lines. Functional experiments verified that compounds 10 and 39 inhibited necroptosis by downregulating the phosphorylation of RIPK3 and MLKL. Moreover, compound 39 also reduced the phosphorylation of RIPK1. Compounds 10, 33, and 34 displayed potent inhibitory activities against RSL-3 induced ferroptosis with the EC50 value of 3.0 µM, 0.4 µM, and 0.1 µM, respectively. Compound 10 inhibited ferroptosis by the downregulation of HMOX1, while compounds 33 and 34 inhibited ferroptosis through regulation of NRF2/SLC7A11/GCLM axis. However, these compounds only showed weak effect in either the necroptosis or ferroptosis relative mouse disease models. Further studies of pharmacokinetics and pharmacodynamics might improve their in vivo bioactivities.


Asunto(s)
Ferroptosis , Sesquiterpenos , Ratones , Animales , Necroptosis , Aspergillus/química , Sesquiterpenos/química , Sesquiterpenos Monocíclicos
11.
Int Urogynecol J ; 35(6): 1219-1225, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38722560

RESUMEN

INTRODUCTION AND HYPOTHESIS: Myofascial pelvic pain (MFPP), characterized by sensitive trigger points in the pelvic floor muscles, leads to chronic pain and affects various aspects of life. Despite the availability of different treatment modalities, there is limited comparative research on their effectiveness. This study compares radiofrequency (RF) therapy and myofascial manual therapy (MMT) in treating MFPP. We aimed to evaluate pelvic floor muscle strength changes, clinical symptoms, and patient comfort during treatment. METHODS: The study involved 176 participants, divided equally into RF and MMT groups. We assessed pelvic floor pain using the Visual Analogue Scale (VAS), muscle strength using the Modified Oxford Scale (MOS) and surface electromyography (sEMG), clinical symptom improvement through questionnaires, and patient discomfort during treatment. RESULTS: Both RF and MMT groups significantly reduced pelvic floor and paraurethral muscle pain (VAS scores, p < 0.001). RF treatment significantly decreased vaginal laxity in its group (p < 0.001), with no notable change in the MMT group (p = 0.818). RF therapy also resulted in greater patient comfort than MMT (p < 0.001). Although both treatments improved clinical symptoms, there was no significant difference between the two (p = 0.692). MOS scores and pelvic floor sEMG values showed no significant differences between the groups before and after treatment (p > 0.05). CONCLUSIONS: Both RF and MMT effectively alleviate pelvic floor pain and improve clinical symptoms in MFPP patients. RF therapy, however, offers additional benefits in reducing vaginal laxity and enhancing treatment comfort.


Asunto(s)
Manipulaciones Musculoesqueléticas , Síndromes del Dolor Miofascial , Diafragma Pélvico , Dolor Pélvico , Terapia por Radiofrecuencia , Humanos , Femenino , Adulto , Dolor Pélvico/terapia , Persona de Mediana Edad , Diafragma Pélvico/fisiopatología , Síndromes del Dolor Miofascial/terapia , Terapia por Radiofrecuencia/métodos , Manipulaciones Musculoesqueléticas/métodos , Resultado del Tratamiento , Dimensión del Dolor , Fuerza Muscular , Electromiografía
12.
Appl Opt ; 63(6): 1529-1537, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38437365

RESUMEN

Photon counting is an effective way to enhance the dynamic range of the data acquisition system (DAQ) in Raman lidars. However, there exists a deficiency of relatively high dead times among current options, which necessitates an additional calibration procedure for the nonlinearity of the photon counting signal, thus leading to unanticipated errors. A field programmable gate array (FPGA)-based photon counting module has been proposed and implemented in a Raman lidar, offering two operational channels. Through observational experiments, it was determined that this module has an overall dead time of 1.13 ns taking advantage of the high-speed amplifier/discriminator pair and the logic design, a significant improvement compared to the 4.35 ns of a commercially used Licel transient recorder within the same counting rate range. This notably low dead time implies that its output maintains sufficient linearity even at substantially high counting rates. As a result, the need for a dead time calibration procedure prior to signal integration with the analog signal is eliminated, reducing uncertainty in the final integrated signal, and even in the retrieval result. The backscattering result of the comparison between this module and a transient recorder indicates that a more precise performance can be acquired benefiting from this hardware upgrading.

13.
Curr Microbiol ; 81(2): 64, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38225342

RESUMEN

Soil microbial communities are engineers of important biogeochemical processes and play a critical role in regulating the functions and stability of forest ecosystem. However, few studies have assessed microbial interactions during forest conversion, which is essential to the understanding of the structure and function of soil microbiome. Herein, we investigated the co-occurrence network pattern and putative functions of fungal and bacterial communities in forest-transforming areas (five sites that cover the typical forests) using high-throughput sequencing of the ITS genes and 16S rRNA. Our study showed that the bacterial network had higher average connectivity and more links than fungal network, which might indicate that the bacterial community had more complex internal interactions compared with fungal one. Alphaproteobacteria_unclassfied, Telmatobacter, 0319-6A21 and Latescibacteria_unclassfied were the keystone taxa in bacterial network. For the fungal community network, the keystone taxon was Ceratobasidium. A structural equation model indicated that the available potassium and total organic carbon were important soil environmental factors, which affected all microbial modules, including bacterial and fungi. Total nitrogen had significant effects on the bacterial module that contains a relatively rich group of nitrogen cycling functions, and pH influenced the bacterial module which have higher potential functions of carbon cycling. And, more fungal modules were directly affected by forest structure (S Tree) compared with bacterial ones. This study provides new insights into our understanding of the feedback of underground creatures to forest conversion and highlights the importance of microbial modules in the nutrient cycling process.


Asunto(s)
Ecosistema , Microbiota , Suelo/química , ARN Ribosómico 16S/genética , Microbiología del Suelo , Bosques , Microbiota/genética , Bacterias/genética , Carbono , Nitrógeno/análisis
14.
Eur Spine J ; 33(2): 517-524, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38038760

RESUMEN

BACKGROUND: Musculoskeletal disorders after childbirth are common, but current studies often have a narrow focus, concentrating on particular areas and neglecting a thorough evaluation of pain locations and overall severity. This research aimed to determine the occurrence, spread, severity, and root causes of musculoskeletal discomfort in females during the 6-8 week period after giving birth, focusing on investigating the link between pain and posture. METHODS: This study collected data from 432 postpartum women, 6-8 weeks post-delivery, focusing on ten posture angles captured photographically and analysed using Exbody software. Participants also filled out structured questionnaires on pregnancy history, the Short Form McGill Pain Questionnaire (SF-MPQ) scores, physical activity patterns, and involvement in household and neonatal care tasks. RESULTS: In our research, 49.8% of the respondents experienced pain after childbirth in different regions of their bodies. Utilising SF-MPQ, the mean Pain Rating Index was 7.35 (SD = 5.93) and Present Pain Intensity and Visual Analog Scale was 3.13 (SD = 2.09). Among the evaluated postural angles, only the Q-angle exhibited a noteworthy correlation with knee discomfort. Individuals with less involvement in household and newborn care tasks had a significantly lower occurrence of postpartum pain, with a decrease of 76% (OR = 0.243, p = 0.001). Similarly, those who shared these responsibilities had a 53% decreased likelihood (OR = 0.468, p = 0.008) of experiencing postpartum pain. CONCLUSION: Many postpartum women experience moderate-intensity pain in various body regions. Pain's correlation with posture was limited. Reducing physical strain during infant care notably decreased postpartum pain, underscoring the need for holistic support for postpartum women.


Asunto(s)
Dolor Musculoesquelético , Embarazo , Lactante , Recién Nacido , Femenino , Humanos , Dolor Musculoesquelético/diagnóstico , Dolor Musculoesquelético/epidemiología , Dimensión del Dolor , Factores de Riesgo , Ejercicio Físico , Periodo Posparto
15.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001612

RESUMEN

Multimodal imaging-the ability to acquire images of an object through more than one imaging mode simultaneously-has opened additional perspectives in areas ranging from astronomy to medicine. In this paper, we report progress toward combining optical and magnetic resonance (MR) imaging in such a "dual" imaging mode. They are attractive in combination because they offer complementary advantages of resolution and speed, especially in the context of imaging in scattering environments. Our approach relies on a specific material platform, microdiamond particles hosting nitrogen vacancy (NV) defect centers that fluoresce brightly under optical excitation and simultaneously "hyperpolarize" lattice [Formula: see text] nuclei, making them bright under MR imaging. We highlight advantages of dual-mode optical and MR imaging in allowing background-free particle imaging and describe regimes in which either mode can enhance the other. Leveraging the fact that the two imaging modes proceed in Fourier-reciprocal domains (real and k-space), we propose a sampling protocol that accelerates image reconstruction in sparse-imaging scenarios. Our work suggests interesting possibilities for the simultaneous optical and low-field MR imaging of targeted diamond nanoparticles.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Imagen Multimodal/métodos , Imagen Óptica/métodos , Fluorescencia , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen Multimodal/instrumentación , Nanopartículas/química , Nanopartículas/ultraestructura , Nitrógeno/química , Imagen Óptica/instrumentación , Fantasmas de Imagen
16.
Mikrochim Acta ; 191(7): 371, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38839652

RESUMEN

Industrialization and agricultural demand have both improved human life and led to environmental contamination. Especially the discharge of a lot of poisonous and harmful gases, including ammonia, ammonia pollution has become a pressing problem. High concentrations of ammonia can pose significant threats to both the environment and human health. Therefore, accurate monitoring and detection of ammonia gas are crucial. To address this challenge, we have developed an ammonia gas sensor using In(OH)3/Ti3C2Tx nanocomposites through an in-situ electrostatic self-assembly process. This sensor was thoroughly characterized using advanced techniques like XRD, XPS, BET, and TEM. In our tests, the I/M-2 sensor exhibited remarkable performance, achieving a 16.8% response to 100 ppm NH3 at room temperature, which is a 3.5-fold improvement over the pure Ti3C2Tx MXene sensor. Moreover, it provides swift response time (20 s), high response to low NH3 concentrations (≤ 10 ppm), and excellent long-term stability (30 days). These exceptional characteristics indicate the immense potential of our In(OH)3/Ti3C2Tx gas sensor in ammonia detection.

17.
Int J Mol Sci ; 25(10)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38791176

RESUMEN

Extensive microbial interactions occur within insect hosts. However, the interactions between the Huanglongbing (HLB) pathogen and endosymbiotic bacteria within the Asian citrus psyllid (ACP, Diaphorina citri Kuwayama) in wild populations remain elusive. Thus, this study aimed to detect the infection rates of HLB in the ACP across five localities in China, with a widespread prevalence in Ruijin (RJ, 58%), Huidong (HD, 28%), and Lingui (LG, 15%) populations. Next, microbial communities of RJ and LG populations collected from citrus were analyzed via 16S rRNA amplicon sequencing. The results revealed a markedly higher microbial diversity in the RJ population compared to the LG population. Moreover, the PCoA analysis identified significant differences in microbial communities between the two populations. Considering that the inter-population differences of Bray-Curtis dissimilarity in the RJ population exceeded those between populations, separate analyses were performed. Our findings indicated an increased abundance of Enterobacteriaceae in individuals infected with HLB in both populations. Random forest analysis also identified Enterobacteriaceae as a crucial indicator of HLB infection. Furthermore, the phylogenetic analysis suggested a potential regulatory role of ASV4017 in Enterobacteriaceae for ACP, suggesting its possible attractant activity. This research contributes to expanding the understanding of microbial communities associated with HLB infection, holding significant implications for HLB prevention and treatment.


Asunto(s)
Enterobacteriaceae , Hemípteros , Filogenia , Enfermedades de las Plantas , ARN Ribosómico 16S , Animales , Hemípteros/microbiología , Enterobacteriaceae/genética , Enterobacteriaceae/clasificación , Enterobacteriaceae/patogenicidad , ARN Ribosómico 16S/genética , Enfermedades de las Plantas/microbiología , China/epidemiología , Citrus/microbiología , Microbiota
18.
Molecules ; 29(4)2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38398659

RESUMEN

In our research on naturally occurring sesquiterpenes, eight shizukaol-type dimers, one chlorahololide-type dimer, and one sarcanolide-type dimer were isolated from the roots of Chloranthus fortunei. As the project was implemented, we accidentally discovered that shizukaol-type dimers can be converted into peroxidized chlorahololide-type dimers. This potential change was discovered after simulations of the changes in corresponding shizukaols showed that three peroxide products were generated (1-3), indicating that peroxidation reactions occurred. HPLC-HR-MS analysis results obtained for the shizukaol derivatives further demonstrate that the reaction occurred, and the type of substituent of small organic ester moieties at positions C-15' and C-13' of unit B were not decisively related to the reaction. Quantum chemical calculations of the mode dimer further demonstrated this phenomenon. The highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy of the precursor and production revealed the advantageous yield of 4ß-hydroperoxyl production. Additionally, the potential reaction mechanism was speculated and validated using the free energy in the reaction which successfully explained the feasibility of the reaction. Finally, the anti-inflammatory activity of the precursors and products was evaluated, and the products of peroxidation showed better anti-inflammatory activity.


Asunto(s)
Artefactos , Sesquiterpenos , Antiinflamatorios/farmacología , Sesquiterpenos/química
19.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1260-1265, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621973

RESUMEN

A variety of compounds in Artemisia annua were simultaneously determined to evaluate the quality of A. annua from multiple perspectives. A method based on ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS) was established for the simultaneous determination of seven compounds: amorpha-4,11-diene, artemisinic aldehyde, dihydroartemisinic acid, artemisinic acid, artemisinin B, artemisitene, and artemisinin, in A. annua. The content of the seven compounds in different tissues(roots, stems, leaves, and lateral branches) of A. annua were compared. The roots, stems, leaves, and lateral branches of four-month-old A. annua were collected and the content of seven artemisinin-related compounds in different tissues was determined. A multi-reaction monitoring(MRM) acquisition mode of UPLC-QQQ-MS/MS was used, with a positive ion mode of atmospheric pressure chemical ion source(APCI). Chromatographic separation was achieved on an Eclipse Plus RRHD C_(18) column(2.1 mm×50 mm, 1.8 µm). The gradient elution was performed with the mobile phase consisted of formic acid(0.1%)-ammonium formate(5 mmol·L~(-1))(A) and the methanol(B) gradient program of 0-8 min, 55%-100% B, 8-11 min, 100% B, and equilibrium for 3 min, the flow rate of 0.6 mL·min~(-1), the column temperature of 40 ℃, the injection volume of 5 µL, and the detection time of 8 min. Through methodological investigation, a method based on UPLC-QQQ-MS/MS was established for the simultaneous quantitative determination of seven representative compounds involved in the biosynthesis of artemisinin. The content of artemisinin in A. annua was higher than that of artemisinin B, and the content of artemisinin and dihydroartemisinic acid were high in all the tissues of A. annua. The content of the seven compounds varied considerably in different tissues, with the highest levels in the leaves and neither artemisinene nor artemisinic aldehyde was detected in the roots. In this study, a quantitative method based on UPLC-QQQ-MS/MS for the simultaneous determination of seven representative compounds involved in the biosynthesis of artemisinin was established, which was accurate, sensitive, and highly efficient, and can be used for determining the content of artemisinin-related compounds in A. annua, breeding new varieties, and controlling the quality of Chinese medicinal materials.


Asunto(s)
Artemisia annua , Artemisininas , Lactonas , Artemisia annua/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Fitomejoramiento , Artemisininas/análisis , Aldehídos
20.
BMC Genomics ; 24(1): 648, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891463

RESUMEN

BACKGROUND: The Begonia species are common shade plants that are mostly found in southwest China. They have not been well studied despite their medicinal and decorative uses because gene penetration, decreased adaptability, and restricted availability are all caused by frequent interspecific hybridization. RESULT: To understand the patterns of mutation in the chloroplast genomes of different species of Begonia, as well as their evolutionary relationships, we collected seven Begonia species in China and sequenced their chloroplast genomes. Begonia species exhibit a quadripartite structure of chloroplast genomes (157,634 - 169,694 bp), consisting of two pairs of inverted repeats (IR: 26,529 - 37,674 bp), a large single copy (LSC: 75,477 - 86,500 bp), and a small single copy (SSC: 17,861 - 18,367 bp). 128-143 genes (comprising 82-93 protein-coding genes, 8 ribosomal RNAs, and 36-43 transfer RNAs) are found in the chloroplast genomes. Based on comparative analyses, this taxon has a relatively similar genome structure. A total of six substantially divergent DNA regions (trnT-UGU-trnL-UAA, atpF-atpH, ycf4-cemA, psbC-trnS-UGA, rpl32-trnL-UAG, and ccsA-ndhD) are found in the seventeen chloroplast genomes. These regions are suitable for species identification and phylogeographic analysis. Phylogenetic analysis shows that Begonia species that were suited to comparable environments grouped in a small clade and that all Begonia species formed one big clade in the phylogenetic tree, supporting the genus' monophyly. In addition, positive selection sites were discovered in eight genes (rpoC1, rpoB, psbE, psbK, petA, rps12, rpl2, and rpl22), the majority of which are involved in protein production and photosynthesis. CONCLUSION: Using these genome resources, we can resolve deep-level phylogenetic relationships between Begonia species and their families, leading to a better understanding of evolutionary processes. In addition to enhancing species identification and phylogenetic resolution, these results demonstrate the utility of complete chloroplast genomes in phylogenetically and taxonomically challenging plant groupings.


Asunto(s)
Begoniaceae , Genoma del Cloroplasto , Humanos , Filogenia , Begoniaceae/genética , Genómica/métodos , Cloroplastos/genética , Secuencia de Bases
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