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1.
Sci Total Environ ; 944: 173961, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38876338

RESUMO

The sulfur (S) cycle is an important biogeochemical cycle with profound implications for both cellular- and ecosystem-level processes by diverse microorganisms. Mangrove sediments are a hotspot of biogeochemical cycling, especially for the S cycle with high concentrations of S compounds. Previous studies have mainly focused on some specific inorganic S cycling processes without paying specific attention to the overall S-cycling communities and processes as well as organic S metabolism. In this study, we comprehensively analyzed the distribution, ecological network and assembly mechanisms of S cycling microbial communities and their changes with sediment depths using metagenome sequencing data. The results showed that the abundance of gene families involved in sulfur oxidation, assimilatory sulfate reduction, and dimethylsulfoniopropionate (DMSP) cleavage and demethylation decreased with sediment depths, while those involved in S reduction and dimethyl sulfide (DMS) transformation showed an opposite trend. Specifically, glpE, responsible for converting S2O32- to SO32-, showed the highest abundance in the surface sediment and decreased with sediment depths; in contrast, high abundances of dmsA, responsible for converting dimethyl sulfoxide (DMSO) to DMS, were identified and increased with sediment depths. We identified Pseudomonas and Streptomyces as the main S-cycling microorganisms, while Thermococcus could play an import role in microbial network connections in the S-cycling microbial community. Our statistical analysis showed that both taxonomical and functional compositions were generally shaped by stochastic processes, while the functional composition of organic S metabolism showed a transition from stochastic to deterministic processes. This study provides a novel perspective of diversity distribution of S-cycling functions and taxa as well as their potential assembly mechanisms, which has important implications for maintaining mangrove ecosystem functions.


Assuntos
Sedimentos Geológicos , Microbiota , Enxofre , Áreas Alagadas , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Enxofre/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética
2.
Radiat Oncol ; 19(1): 62, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802888

RESUMO

BACKGROUND: The effectiveness and safety of moderately hypofractionated radiotherapy (HFRT) in patients undergoing breast-conserving surgery (BCS) has been demonstrated in several pivotal randomized trials. However, the feasibility of applying simultaneous integrated boost (SIB) to the tumor bed and regional node irradiation (RNI) using modern radiotherapy techniques with HFRT needs further evaluation. METHODS: This prospective, multi-center, randomized controlled, non-inferiority phase III trial aims to determine the non-inferiority of HFRT combined with SIB (HFRTsib) compared with conventional fractionated radiotherapy with sequential boost (CFRTseq) in terms of five-year locoregional control rate in breast cancer patients undergoing upfront BCS. A total of 2904 participants will be recruited and randomized in a 1:1 ratio into the HFRTsib and CFRTseq groups. All patients will receive whole breast irradiation, and those with positive axillary nodes will receive additional RNI, including internal mammary irradiation. The prescribed dose for the HFRTsib group will be 40 Gy in 15 fractions, combined with a SIB of 48 Gy in 15 fractions to the tumor bed. The CFRTseq group will receive 50 Gy in 25 fractions, with a sequential boost of 10 Gy in 5 fractions to the tumor bed. DISCUSSION: This trial intends to assess the effectiveness and safety of SIB combined with HFRT in early breast cancer patients following BCS. The primary endpoint is locoregional control, and the results of this trial are expected to offer crucial evidence for utilizing HFRT in breast cancer patients after BCS. TRIAL REGISTRATION: This trial was registered at ClincalTrials.gov (NCT04025164) on July 18, 2019.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Hipofracionamento da Dose de Radiação , Humanos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Feminino , Estudos Prospectivos , Adulto , Pessoa de Meia-Idade , Idoso , Radioterapia de Intensidade Modulada/métodos , Radioterapia Adjuvante/métodos , Adulto Jovem
3.
Phytochemistry ; 223: 114109, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38697239

RESUMO

A previously undescribed open-loop decarbonizing cembranolide, sarcocinerenolide A, and eight undescribed cembranolides, sarcocinerenolides B-I, characterized by poly-membered oxygen ring fragments were isolated from the soft coral Sarcophyton cinereum collected from the South China Sea. The structures and absolute configurations of these previously undescribed compounds were precisely determined by analysis of NMR data, DP4+ and ECD spectra. The bioactivities of the compounds were evaluated using zebrafish models and sarcocinerenolides C and H exhibited anti-thrombotic activity.


Assuntos
Antozoários , Diterpenos , Animais , Antozoários/química , Diterpenos/química , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , Estrutura Molecular , Peixe-Zebra , Fibrinolíticos/farmacologia , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , China , Relação Estrutura-Atividade
4.
Biosci Trends ; 18(2): 176-186, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38684402

RESUMO

This study aimed to compare the efficacy and effect on lipid profiles of Ainuovirine (ANV)- and efavirenz (EFV) -based regimens in treatment-naïve people living with HIV-1 (PLWH) at week 24. The proportion of PLWH achieving HIV-1 RNA < the limit of quantification in the ANV group was significantly higher than that in the EFV group (89.18% vs. 76.04%, P = 0.002). The mean change of log10 HIV-1 RNA from baseline was greater (-4.34 vs. -4.18, P < 0.001), the median change from baseline in CD4+ T cell count increased more (106.00 cells/µL vs. 92.00 cells/µL, P = 0.007) in the ANV group, while the CD4+/CD8+ ratio was similar (0.15 vs. 0.20, P = 0.167) between the two groups. The mean changes from baseline in total cholesterol (-0.02 for ANV vs. 0.25 mmol/L for EFV, P < 0.001), triglyceride (-0.14 for ANV vs. 0.11 mmol/L for EFV, P = 0.024), and low-density lipoprotein cholesterol (-0.07 for ANV vs. 0.15 mmol/L for EFV, P < 0.001) was significantly different between the two groups. The percentage of patients with improved lipid profiles was significantly higher in the ANV group (37.44 %) than in the EFV group (29.55%, P = 0.0495). The incidence of any adverse events in the ANV group was significantly lower than that in the EFV group at week 12 (6.2% vs. 30.7%, P < 0.001) and was comparable at week 24 (3.6% vs. 5.5%, P = 0.28). The ANV-based regimen was well tolerated and lipid-friendly in treatment-naïve PLWH.


Assuntos
Alcinos , Fármacos Anti-HIV , Benzoxazinas , Ciclopropanos , Infecções por HIV , HIV-1 , Humanos , Ciclopropanos/uso terapêutico , Ciclopropanos/administração & dosagem , Benzoxazinas/uso terapêutico , Alcinos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/sangue , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Masculino , Feminino , Adulto , Estudos Retrospectivos , Fármacos Anti-HIV/uso terapêutico , Lipídeos/sangue , Pessoa de Meia-Idade , Resultado do Tratamento , Contagem de Linfócito CD4
5.
Mol Ecol Resour ; 24(5): e13950, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38567644

RESUMO

Lignin, as an abundant organic carbon, plays a vital role in the global carbon cycle. However, our understanding of the global lignin-degrading microbiome remains elusive. The greatest barrier has been absence of a comprehensive and accurate functional gene database. Here, we first developed a curated functional gene database (LCdb) for metagenomic profiling of lignin degrading microbial consortia. Via the LCdb, we draw a clear picture describing the global biogeography of communities with lignin-degrading potential. They exhibit clear niche differentiation at the levels of taxonomy and functional traits. The terrestrial microbiomes showed the highest diversity, yet the lowest correlations. In particular, there were few correlations between genes involved in aerobic and anaerobic degradation pathways, showing a clear functional redundancy property. In contrast, enhanced correlations, especially closer inter-connections between anaerobic and aerobic groups, were observed in aquatic consortia in response to the lower diversity. Specifically, dypB and dypA, are widespread on Earth, indicating their essential roles in lignin depolymerization. Estuarine and marine consortia featured the laccase and mnsod genes, respectively. Notably, the roles of archaea in lignin degradation were revealed in marine ecosystems. Environmental factors strongly influenced functional traits, but weakly shaped taxonomic groups. Null mode analysis further verified that composition of functional traits was deterministic, while taxonomic composition was highly stochastic, demonstrating that the environment selects functional genes rather than taxonomic groups. Our study not only develops a useful tool to study lignin degrading microbial communities via metagenome sequencing but also advances our understanding of ecological traits of these global microbiomes.


Assuntos
Ecossistema , Lignina , Metagenômica , Microbiota , Lignina/metabolismo , Microbiota/genética , Microbiota/fisiologia , Metagenômica/métodos , Archaea/genética , Archaea/classificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Consórcios Microbianos/genética , Consórcios Microbianos/fisiologia , Metagenoma
7.
Front Oncol ; 14: 1382142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590646

RESUMO

Harmine is a naturally occurring ß-carboline alkaloid originally isolated from Peganum harmala. As a major active component, harmine exhibits a broad spectrum of pharmacological properties, particularly remarkable antitumor effects. Recent mechanistic studies have shown that harmine can inhibit cancer cell proliferation and metastasis through epithelial-to-mesenchymal transition, cell cycle regulation, angiogenesis, and the induction of tumor cell apoptosis. Furthermore, harmine reduces drug resistance when used in combination with chemotherapeutic drugs. Despite its remarkable antitumor activity, the application of harmine is limited by its poor solubility and toxic side effects, particularly neurotoxicity. Novel harmine derivatives have demonstrated strong clinical application prospects, but further validation based on drug activity, acute toxicity, and other aspects is necessary. Here, we present a review of recent research on the action mechanism of harmine in cancer treatment and the development of its derivatives, providing new insights into its potential clinical applications and strategies for mitigating its toxicity while enhancing its efficacy.

8.
bioRxiv ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38645117

RESUMO

Glioblastomas (GBMs) are dreadful brain tumors with abysmal survival outcomes. GBM EVs dramatically affect normal brain cells (largely astrocytes) constituting the tumor microenvironment (TME). EVs from different patient-derived GBM spheroids induced differential transcriptomic, secretomic, and proteomic effects on cultured astrocytes/brain tissue slices as GBM EV recipients. The net outcome of brain cell differential changes nonetheless converges on increased tumorigenicity. GBM spheroids and brain slices were derived from neurosurgical patient tissues following informed consent. Astrocytes were commercially obtained. EVs were isolated from conditioned culture media by ultrafiltration, ultraconcentration, and ultracentrifugation. EVs were characterized by nanoparticle tracking analysis, electron microscopy, biochemical markers, and proteomics. Astrocytes/brain tissues were treated with GBM EVs before downstream analyses. EVs from different GBMs induced brain cells to alter secretomes with pro-inflammatory or TME-modifying (proteolytic) effects. Astrocyte responses ranged from anti-viral gene/protein expression and cytokine release to altered extracellular signal-regulated protein kinase (ERK1/2) signaling pathways, and conditioned media from EV-treated cells increased GBM cell proliferation. Thus, astrocytes/brain slices treated with different GBM EVs underwent non-identical changes in various 'omics readouts and other assays, indicating "personalized" tumor-specific GBM EV effects on the TME. This raises concern regarding reliance on "model" systems as a sole basis for translational direction. Nonetheless, net downstream impacts from differential cellular and TME effects still led to increased tumorigenic capacities for the different GBMs.

9.
J Nat Prod ; 87(4): 1150-1158, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38548686

RESUMO

A detailed chemical study of the extract from the soft coral Stereonephthya bellissima resulted in the isolation and identification of seven new sesquiterpenoids, bellissinanes A-G (1-7), along with four new diterpenes (8-11). Bellissinane A (1) is the third reported nardosinane-type sesquiterpene bearing a 6/5/6 tricyclic system. Bellissinanes C and D (3, 4) contain a phenylethylamine fragment, which is relatively unusual in marine organisms. Bellissinanes E-G (5-7) belong to the rare class of nornardosinane sesquiterpenoids. Structurally uncommon octahydro-1H-indenyl-type and prenyleudesmane-type skeletons were characterized for herpetopanone B (8) and bellissimain A (9), respectively. Bellissinane E (5) exhibited in vivo angiogenesis-promoting activity.


Assuntos
Antozoários , Diterpenos , Sesquiterpenos , Animais , Estrutura Molecular , Antozoários/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Ressonância Magnética Nuclear Biomolecular , Biologia Marinha , Terpenos/química , Terpenos/farmacologia , Terpenos/isolamento & purificação
10.
Pediatr Radiol ; 54(4): 646-652, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38472490

RESUMO

Hand-wrist radiography is the most common and accurate method for evaluating children's bone age. To reduce the scattered radiation of radiosensitive organs in bone age assessment, we designed a small X-ray instrument with radioprotection function by adding metal enclosure for X-ray shielding. We used a phantom operator to compare the scattered radiation doses received by sensitive organs under three different protection scenarios (proposed instrument, radiation personal protective equipment, no protection). The proposed instrument showed greater reduction in the mean dose of a single exposure compared with radiation personal protective equipment especially on the left side which was proximal to the X-ray machine (≥80.0% in eye and thyroid, ≥99.9% in breast and gonad). The proposed instrument provides a new pathway towards more convenient and efficient radioprotection.


Assuntos
Proteção Radiológica , Criança , Humanos , Doses de Radiação , Raios X , Radiografia , Proteção Radiológica/métodos , Fluoroscopia , Imagens de Fantasmas
11.
World Neurosurg ; 186: e316-e325, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38548046

RESUMO

BACKGROUND: Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass surgery has been widely adopted in treating moyamoya disease (MMD). Geometric variations including high tortuosity and stenosis exist in many cases, but the hemodynamic effects have not been comprehensively evaluated. We aim to evaluate the hemodynamic effects of bypass geometry variations based on patient-specific data. METHODS: In total, 17 patients with MMD who underwent STA-MCA bypass surgery with highly tortuous bypass geometry were included. For each patient, the original 3-dimensional structure of STA-MCA bypass was reconstructed from clinical imaging data. The bypass structure was virtually improved by removing the tortuosity and stenosis. Computational fluid dynamics simulation was performed on both bypass structures under identical patient-specific condition. The simulated hemodynamic parameters of the bypass and its distal branches were compared between the original and virtually improved bypass geometries in all cases using paired t-test or Wilcoxon signed-rank test. The changes of hemodynamic parameters were compared between the cases with and without mild-to-moderate stenosis (44.0-70.3% in diameter) in the bypass using t-test or Mann-Whitney U test. RESULTS: The virtual improvement of bypass geometry significantly increased the flow rate of the bypass and its distal branches (P < 0.05) and decreased the transcranial flow resistance (P < 0.05). The hemodynamic changes in cases with stenosis removal were significantly greater than those without stenosis (P < 0.05). CONCLUSIONS: High tortuosity and stenosis can significantly change the hemodynamics of STA-MCA bypass, and the optimization of bypass geometry deserves further consideration.


Assuntos
Revascularização Cerebral , Hemodinâmica , Artéria Cerebral Média , Doença de Moyamoya , Artérias Temporais , Humanos , Doença de Moyamoya/cirurgia , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/fisiopatologia , Artéria Cerebral Média/cirurgia , Artéria Cerebral Média/diagnóstico por imagem , Feminino , Artérias Temporais/cirurgia , Artérias Temporais/diagnóstico por imagem , Masculino , Revascularização Cerebral/métodos , Hemodinâmica/fisiologia , Adulto , Pessoa de Meia-Idade , Constrição Patológica/cirurgia , Adulto Jovem , Adolescente , Criança
12.
Nat Prod Res ; : 1-8, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427608

RESUMO

Female germline stem cells (FGSCs) are renewable sources of oocytes that play an indispensable role in re-establishing mammal fertility. Here, we have established FGSCs from neonatal mice, which exhibit characteristics of germline stem cells. We show that compared with monomeric trigonelline and diosgenin, macromolecular compounds Cistanche deserticola polysaccharides (CDPs) in Chinese herbal medicine can enhance the ability of FGSCs to differentiate into oocytes at appropriate concentrations while maintaining self-renewal in vitro. In contrast, trigonelline and diosgenin inhibited the expression of germ cell-specific genes while reducing cell proliferation activity. In summary, CDPs could induce the differentiation and self-renewal of FGSCs in vitro. The comparison of the effects of the active components of different types of Chinese medicine will provide a reference for the development of clinical drugs in the future, and help to elucidate the development process of FGSCs.

13.
Antimicrob Agents Chemother ; 68(4): e0166823, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38483175

RESUMO

Ainuovirine (ANV), a novel non-nucleoside reverse-transcriptase inhibitor (NNRTI), was approved in China in 2021. In a previous randomized phase 3 trial, ANV demonstrated non-inferior efficacy relative to efavirenz (EFV) and was associated with lower rates of dyslipidemia. In this study, we aimed to explore lipid changes in treatment-experienced people with human immunodeficiency virus (HIV)-1 (PWH) switching to ANV from EFV in real world. At week 24, 96.65% of patients in the ANV group and 93.25% in the EFV group had HIV-1 RNA levels below the limit of quantification (LOQ). Median changes from baseline in CD4 +T cell counts (37.0 vs 36.0 cells/µL, P = 0.886) and CD4+/CD8 +ratio (0.03 vs 0.10, P = 0.360) were similar between the two groups. The ANV group was superior to the EFV group in mean changes in total cholesterol (TC, -0.06 vs 0.26 mmol/L, P = 0.006), triglyceride (TG, -0.6 vs 0.14 mmol/L, P < 0.001), high-density lipoprotein cholesterol (HDL-C, 0.09 vs 0.08 mmol/L, P = 0.006), and low-density lipoprotein cholesterol (LDL-C, -0.18 vs 0.29 mmol/L, P < 0.001) at week 24. We also observed that a higher proportion of patients demonstrated improved TC (13.55% vs 4.45%, P = 0.015) or LDL-C (12.93% vs 6.89%, P = 0.017), and a lower proportion of patients showed worsened LDL-C (5.57% vs 13.52%, P = 0.017) with ANV than with EFV at week 24. In conclusion, we observed good efficacy and favorable changes in lipids in switching to ANV from EFV in treatment-experienced PWH in real world, indicating a promising switching option for PWH who may be more prone to metabolic or cardiovascular diseases.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , Infecções por HIV/tratamento farmacológico , Estudos Retrospectivos , LDL-Colesterol , Benzoxazinas/uso terapêutico , Benzoxazinas/farmacologia , Alcinos/farmacologia , Alcinos/uso terapêutico , Ciclopropanos/farmacologia , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/farmacologia
15.
Vet Res ; 55(1): 40, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532469

RESUMO

The interaction between viral components and cellular proteins plays a crucial role in viral replication. In a previous study, we showed that the 3'-untranslated region (3'-UTR) is an essential element for the replication of duck hepatitis A virus type 1 (DHAV-1). However, the underlying mechanism is still unclear. To gain a deeper understanding of this mechanism, we used an RNA pull-down and a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry assay to identify new host factors that interact with the 3'-UTR. We selected interleukin-2 enhancer binding factor 2 (ILF2) for further analysis. We showed that ILF2 interacts specifically with both the 3'-UTR and the 3D polymerase (3Dpol) of DHAV-1 through in vitro RNA pull-down and co-immunoprecipitation assays, respectively. We showed that ILF2 negatively regulates viral replication in duck embryo fibroblasts (DEFs), and that its overexpression in DEFs markedly suppresses DHAV-1 replication. Conversely, ILF2 silencing resulted in a significant increase in viral replication. In addition, the RNA-dependent RNA polymerase (RdRP) activity of 3Dpol facilitated viral replication by enhancing viral RNA translation efficiency, whereas ILF2 disrupted the role of RdRP in viral RNA translation efficiency to suppress DHAV-1 replication. At last, DHAV-1 replication markedly suppressed the expression of ILF2 in DEFs, duck embryo hepatocytes, and different tissues of 1 day-old ducklings. A negative correlation was observed between ILF2 expression and the viral load in primary cells and different organs of young ducklings, suggesting that ILF2 may affect the viral load both in vitro and in vivo.


Assuntos
Vírus da Hepatite do Pato , Hepatite Viral Animal , Infecções por Picornaviridae , Doenças das Aves Domésticas , Animais , Interleucina-2/genética , RNA Polimerase Dependente de RNA/genética , Regulação da Expressão Gênica , RNA Viral/genética , Patos/genética , Infecções por Picornaviridae/veterinária
17.
BMC Gastroenterol ; 24(1): 95, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438954

RESUMO

Sarcopenia and anemia are common complications in patients with Crohn's Disease (CD). However, few studies have shown the association between sarcopenia and hemoglobin levels in CD patients. This retrospective study aimed to explore such association in Chinese patients with CD. Two hundred and twelve adult CD inpatients who underwent computed tomography (CT) or magnetic resonance imaging (MRI) examinations from July 2019 to December 2021 were included in the study. Sarcopenia was defined according to the cutoff value of skeletal muscle index of lumbar spine 3 (SMI-L3) (< 44.77cm2/m2 for males and < 32.5cm2/m2 for females). The CD patients were divided into two groups based on the presence or absence of sarcopenia. Clinical data, hemoglobin levels, and other laboratory data were retrospectively collected. The association between hemoglobin levels and sarcopenia was analyzed by univariable and multivariable logistic regression analysis. Sarcopenia occurred in 114 CD patients (53.8%). Compared to patients without sarcopenia, patients with sarcopenia had a lower proportion of L1 (30.7% vs. 45.8%, p = 0.032) and B1 classification (58.8% vs. 72.4%, p = 0.037). Patients with sarcopenia had significantly lower levels of hemoglobin (Hb) (116.5 ± 22.8 vs. 128.1 ± 21.0, p < 0.001). The prevalence of sarcopenia increased with the decrease in hemoglobin level (p for trend < 0.05). Linear regression analysis showed that hemoglobin levels were associated with SMI-L3 (ß = 0.091, p = 0.001). Multivariable logistic regression analysis found that higher hemoglobin levels (OR:0.944; 95% CI: 0.947,0.998; p = 0.036) were independent protective factors for sarcopenia. Lower hemoglobin levels are independently associated factors of sarcopenia in adult Chinese patients with CD.


Assuntos
Doença de Crohn , Sarcopenia , Adulto , Feminino , Masculino , Humanos , Sarcopenia/diagnóstico por imagem , Sarcopenia/epidemiologia , Estudos Retrospectivos , Doença de Crohn/complicações , Músculo Esquelético , China/epidemiologia
18.
Int J Biol Macromol ; 264(Pt 2): 130574, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38453125

RESUMO

The prevalent use of disposable plastic tableware presents notable environmental and health risks. An alternative, polylactic acid (PLA), often does not meet usage requirements due to its low crystallization rate. This research introduces an amide-based nucleating agent, BRE-T-100, developed through a straightforward method to enhance the heat resistance and crystallization rate of PLA. This study systematically investigates the impact of BRE-T-100 and other nucleating agents on the properties of PLA composites. The incorporation of 0.8 % BRE-T-100 increases the crystallization temperature of PLA from 109.6 °C to 131.9 °C. Further, the total crystallization time of PLA composites at 120 °C is reduced to <60 s, while maintaining good transparency. BRE-T-100 exhibits superior comprehensive properties compared to talcum, TMC-200, and TMC-300 and is nearly on par with LAK-301. Its application as a nucleating agent in PLA-based disposable tableware shows promise.


Assuntos
Amidas , Temperatura Alta , Poliésteres/química , Temperatura
19.
Gene ; 909: 148288, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38367854

RESUMO

Plant mitochondrial genomes participate in encoding proteins crucial to the major producers of ATP in the cell and replication and heredity of their own DNA. The sequences and structure of the plant mitochondrial genomes profoundly impact these fundamental processes, and studies of plant mitochondrial genomes are needed. We reported the complete sequences of the Rhodomyrtus tomentosa mitochondrial genome here, totaling 400,482 bp. Nanopore ONT reads and PCR amplification provided evidence for recombination mediated by the eight repeat pairs for the R. tomentosa mitochondrial genome. Thirty-eight genes were identified in the R. tomentosa mitochondrial genome. Comparative analyses of the mitochondrial genome and plastome and PCR amplification suggest that five fragments of mitochondrial plastid DNA were unfunctional sequences resulting from intracellular gene transfer. Phylogenetic analysis based on each and all of the 27 mitochondrial protein-coding genes of nine Myrtales species revealed that R. tomentosa always clustered with other species of Myrtaceae. This study uncovered the enormous complexity of the R. tomentosa mitochondrial genome, the active repeat-mediated recombinations, the presence of mitochondrial plastid DNAs, and the topological incongruence of Myrtales among the single-gene trees.


Assuntos
Genoma Mitocondrial , Myrtaceae , Filogenia , Genoma Mitocondrial/genética , Plantas , DNA Mitocondrial/genética , Recombinação Genética
20.
Pharmaceuticals (Basel) ; 17(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38399440

RESUMO

Triple-negative breast cancer (TNBC) poses a therapeutic challenge due to its aggressive nature and lack of targeted therapies. Epigenetic modifications contribute to TNBC tumorigenesis and drug resistance, offering potential therapeutic targets. Recent advancements in three-dimensional (3D) organoid cultures, enabling precise drug screening, hold immense promise for identifying novel compounds targeting TNBC. In this study, we established two patient-derived TNBC organoids and implemented a high-throughput drug screening system using these organoids and two TNBC cell lines. Screening a library of 169 epigenetic compounds, we found that organoid-based systems offer remarkable precision in drug response assessment compared to cell-based models. The top 30 compounds showing the highest drug sensitivity in the initial screening were further assessed in a secondary screen. Four compounds, panobinostat, pacritinib, TAK-901, and JIB-04, targeting histone deacetylase, JAK/STAT, histone demethylases, and aurora kinase pathways, respectively, exhibited potent anti-tumor activity in TNBC organoids, surpassing the effect of paclitaxel. Our study highlights the potential of these novel epigenetic drugs as effective therapeutic agents for TNBC and demonstrates the valuable role of patient-derived organoids in advancing drug discovery.

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