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1.
Nat Commun ; 15(1): 3411, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649721

RESUMO

A central role for nature-based solution is to identify optimal management practices to address environmental challenges, including carbon sequestration and biodiversity conservation. Inorganic fertilization increases plant aboveground biomass but often causes a tradeoff with plant diversity loss. It remains unclear, however, whether organic fertilization, as a potential nature-based solution, could alter this tradeoff by increasing aboveground biomass without plant diversity loss. Here we compile data from 537 experiments on organic and inorganic fertilization across grasslands and croplands worldwide to evaluate the responses of aboveground biomass, plant diversity, and soil organic carbon (SOC). Both organic and inorganic fertilization increase aboveground biomass by 56% and 42% relative to ambient, respectively. However, only inorganic fertilization decreases plant diversity, while organic fertilization increases plant diversity in grasslands with greater soil water content. Moreover, organic fertilization increases SOC in grasslands by 19% and 15% relative to ambient and inorganic fertilization, respectively. The positive effect of organic fertilization on SOC increases with increasing mean annual temperature in grasslands, a pattern not observed in croplands. Collectively, our findings highlight organic fertilization as a potential nature-based solution that can increase two ecosystem services of grasslands, forage production, and soil carbon storage, without a tradeoff in plant diversity loss.

2.
J Hematol Oncol ; 17(1): 18, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627786

RESUMO

The chemo-free concept represents a new direction for managing adult patients with Ph-positive acute lymphoblastic leukemia (Ph + ALL). The tyrosine kinase inhibitors (TKIs), blinatumomab and venetoclax serve as the backbone of chemo-free regimens; several prospective studies involving these drugs have demonstrated high remission rates and promising, albeit short, survival outcomes. This review summarizes the latest updates on chemo-free regimens in the treatment of adult patients with Ph + ALL, presented at the 2023 ASH annual meeting.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Humanos , Estudos Prospectivos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Cromossomo Filadélfia
3.
Helicobacter ; 29(2): e13075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38627919

RESUMO

BACKGROUND: The current standard treatment for Helicobacter pylori infection, which involves a combination of two broad-spectrum antibiotics, faces significant challenges due to its detrimental impact on the gut microbiota and the emergence of drug-resistant strains. This underscores the urgent requirement for the development of novel anti-H. pylori drugs. Zoliflodacin, a novel bacterial gyrase inhibitor, is currently undergoing global phase III clinical trials for treating uncomplicated Neisseria gonorrhoeae. However, there is no available data regarding its activity against H. pylori. MATERIALS AND METHODS: We evaluated the in vitro activity of zoliflodacin against H. pylori clinical isolates (n = 123) with diverse multidrug resistance. We performed DNA gyrase supercoiling and microscale thermophoresis assays to identify the target of zoliflodacin in H. pylori. We analyzed 2262 H. pylori whole genome sequences to identify Asp424Asn and Lys445Asn mutations in DNA gyrase subunit B (GyrB) that are associated with zoliflodacin resistance. RESULTS: Zoliflodacin exhibits potent activity against all tested isolates, with minimal inhibitory concentration (MIC) values ranging from 0.008 to 1 µg/mL (MIC50: 0.125 µg/mL; MIC90: 0.25 µg/mL). Importantly, there was no evidence of cross-resistance to any of the four first-line antibiotics commonly used against H. pylori. We identified GyrB as the primary target of zoliflodacin, with Asp424Asn or Lys445Asn substitutions conferring resistance. Screening of 2262 available H. pylori genomes for the two mutations revealed only one clinical isolate carrying Asp424Asn substitution. CONCLUSION: These findings support the potential of zoliflodacin as a promising candidate for H. pylori treatment, warranting further development and evaluation.


Assuntos
Barbitúricos , Infecções por Helicobacter , Helicobacter pylori , Isoxazóis , Morfolinas , Oxazolidinonas , Compostos de Espiro , Humanos , Antibacterianos/farmacologia , DNA Girase/genética , Farmacorresistência Bacteriana , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Testes de Sensibilidade Microbiana , Ensaios Clínicos Fase III como Assunto
4.
Chemistry ; : e202400950, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38655749

RESUMO

It is usually believed that doping with photosensitizers capable of generating singlet oxygen (1O2) plays a pivotal role in enhancing the afterglow performance of semiconducting polymer nanoparticles (SPNs). However, the effect of doping photosensitizer bearing electron-withdrawing groups has not been reported. Here we report the effect of doping with six photosensitizers possessing different electron-withdrawing groups on the afterglow performance of SPNs using poly[(9,9-di(2-ethylhexyl)-9H-fluo-rene-2,7-vinylene)-co-(1-methoxy-4-(2-ethylhexyloxy)-2,5-phenylenevinylene)] (PF-MEHPPV) as substrate. It was found that the afterglow performance of SPNs was significantly influenced by doping with photosensitizers bearing electron-withdrawing groups. For the doped photosensitizers with strong electron-withdrawing groups, the stronger the electron-withdrawing ability of the group, the worse of the afterglow performance of the SPN regardless of the 1O2 generation ability of the photosensitizer. When the doped photosensitizer exhibited weak or none electron-withdrawing effect, the 1O2 generation ability of the photosensitizer played a dominant role on the afterglow performance of the SPNs. This work deepens the understanding of the design and synthesis of SPNs with different afterglow properties.

5.
Molecules ; 29(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611749

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with a high degree of malignancy and poor prognosis. Tumor-associated macrophages (TAMs) have been identified as significant contributors to the growth and metastasis of TNBC through the secretion of various growth factors and chemokines. Salvianolic acid A (SAA) has been shown to have anti-cancer activities. However, the potential activity of SAA on re-polarized TAMs remains unclear. As there is a correlation between the TAMs and TNBC, this study investigates the effect of SAA on TAMs in the TNBC microenvironment. For that purpose, M2 TAM polarization was induced by two kinds of TNBC-conditioned medium (TNBC-TCM) in the absence or presence of SAA. The gene and protein expression of TAM markers were analyzed by qPCR, FCM, IF, ELISA, and Western blot. The protein expression levels of ERK and p-ERK in M2-like TAMs were analyzed by Western blot. The migration and invasion properties of M2-like TAMs were analyzed by Transwell assays. Here, we demonstrated that SAA increased the expression levels of CD86, IL-1ß, and iNOS in M2-like TAMs and, conversely, decreased the expression levels of Arg-1 and CD206. Moreover, SAA inhibited the migration and invasion properties of M2-like TAMs effectively and decreased the protein expression of TGF-ß1 and p-ERK in a concentration-dependent manner, as well as TGF-ß1 gene expression and secretion. Our current findings for the first time demonstrated that SAA inhibits macrophage polarization to M2-like TAMs by inhibiting the ERK pathway and promotes M2-like TAM re-polarization to the M1 TAMs, which may exert its anti-tumor effect by regulating M1/M2 TAM polarization. These findings highlight SAA as a potential regulator of M2 TAMs and the possibility of utilizing SAA to reprogram M2 TAMs offers promising insights for the clinical management of TNBC.


Assuntos
Ácidos Cafeicos , Lactatos , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Fator de Crescimento Transformador beta1 , Microambiente Tumoral , Macrófagos Associados a Tumor
6.
Shanghai Kou Qiang Yi Xue ; 33(1): 22-29, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583020

RESUMO

PURPOSE: To investigate the role and mechanism of connexin 43(Cx43)in odontoblast differentiation of human dental pulp cells (hDPCs) induced by lipopolysaccharide (LPS). METHODS: The maxillary first molar injury model of SD rats was established. The expression pattern of Cx43 in dental pulp repair after injury was detected by immunofluorescence(IF) staining. hDPCs was respectively stimulated with 0, 1, 10, 100 and 1 000 ng/mL LPS for 6 h to screen the optimal concentration, and then the expression of Cx43 was inhibited and overexpressed in hDPCs. Quantitative real-time PCR(qRT-PCR) and Western blot(WB) were used to detect the expression of Cx43 and dentin sialophosphoprotein (DSPP), dental matrix protein-1 (DMP-1), osterix (Osx) and extracellular signal-regulated kinase (ERK) activity. Furthermore, hDPCs were treated with specific Cx43 channel inhibitors to investigate the effect of Cx43-mediated channel activity in odontoblast differentiation of hDPCs, and to explore the role and mechanism of Cx43 in regulating odontoblast differentiation of hDPCs induced by LPS. Statistical analysis was performed with SPSS 26.0 software package. RESULTS: IF results showed that Cx43 was mainly expressed in the odontoblast layer in healthy dental pulp tissues. At 3-24 h after tooth injury, the expression of Cx43 decreased and then gradually increased to the normal level; from 3 days to 2 weeks after injury, the expression of Cx43 tended to be down-regulated which was in the odontoblast layer and pulp proper. The expression of DSPP mRNA was significantly up-regulated in the hDPCs stimulated with 10 ng/mL LPS for 6 h(P<0.01). Inhibition of Cx43 significantly up-regulated the expression of DSPP, DMP-1 and Osx mRNA induced by LPS in hDPCs(P<0.05), while overexpression of Cx43 obviously inhibited the expression of factors related to LPS-induced odontoblast differentiation(P<0.01) and the fluorescence intensity of DSPP. 10 ng/mL LPS activated ERK signal in hDPCs, and overexpression of Cx43 significantly attenuated the activity of ERK signal induced by LPS(P<0.01). Inhibition of Cx43-mediated hemichannel (HC) promoted mRNA expression of factors related to odontoblast differentiation in hDPCs and the activity of ERK signal induced by LPS(P<0.05), while blocking Cx43-mediated gap junction channel (GJC) inhibited odontoblast differentiation. CONCLUSIONS: Cx43 participates in the regulation of dental pulp repair after injury, and its expression shows a downward trend as a whole. Inhibition of Cx43 or blocking of HC promotes LPS-induced ERK signal activity and odontoblast differentiation of hDPCs.


Assuntos
Conexina 43 , Lipopolissacarídeos , Animais , Humanos , Ratos , Diferenciação Celular/fisiologia , Células Cultivadas , Conexina 43/metabolismo , Polpa Dentária/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Odontoblastos/metabolismo , Ratos Sprague-Dawley , RNA Mensageiro/metabolismo
7.
Curr Med Imaging ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38462826

RESUMO

OBJECTIVE: Accurate prediction of recurrence risk after resction in patients with Hepatocellular Carcinoma (HCC) may help to individualize therapy strategies. This study aimed to develop machine learning models based on preoperative clinical factors and multiparameter Magnetic Resonance Imaging (MRI) characteristics to predict the 1-year recurrence after HCC resection. METHODS: Eighty-two patients with single HCC who underwent surgery were retrospectively analyzed. All patients underwent preoperative gadoxetic acidenhanced MRI examination. Preoperative clinical factors and MRI characteristics were collected for feature selection. Least Absolute Shrinkage and Selection Operator (LASSO) was applied to select the optimal features for predicting postoperative 1-year recurrence of HCC. Four machine learning algorithms, Multilayer Perception (MLP), random forest, support vector machine, and k-nearest neighbor, were used to construct the predictive models based on the selected features. A Receiver Operating Characteristic (ROC) curve was used to assess the performance of each model. RESULTS: Among the enrolled patients, 32 patients experienced recurrences within one year, while 50 did not. Tumor size, peritumoral hypointensity, decreasing ratio of liver parenchyma T1 value (ΔT1), and α-fetoprotein (AFP) levels were selected by using LASSO to develop the machine learning models. The area under the curve (AUC) of each model exceeded 0.72. Among the models, the MLP model showed the best performance with an AUC, accuracy, sensitivity, and specificity of 0.813, 0.742, 0.570, and 0.853, respectively. CONCLUSION: Machine learning models can accurately predict postoperative 1-year recurrence in patients with HCC, which may help to provide individualized treatment.

8.
Colloids Surf B Biointerfaces ; 238: 113876, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38555764

RESUMO

A plasmonic metasurface composed of a self-assembled monolayer of gold nanoparticles allows for fluorescence imaging with high spatial resolution, owing to the collective excitation of localized surface plasmon resonance. Taking advantage of fluorescence imaging confined to the nano-interface, we examined actin organization in breast cancer cell lines with different metastatic potentials during cell adhesion. Live-cell fluorescence imaging confined within tens of nanometers from the substrate shows a high actin density spanning < 1 µm from the cell edge. Live-cell imaging revealed that the breast cancer cell lines exhibited different actin patterns during the initial phase of cell adhesion (∼ 1 h). Non-tumorous MCF10A cells exhibited symmetric actin localization at the cell edge, whereas highly metastatic MDA-MB-231 cells showed asymmetric actin localization, demonstrating rapid polarization of MDA-MB-231 cells upon adhesion. The rapid actin organization observed by our plasmonic metasurface-based fluorescence imaging provides information on how quickly cancer cells sense the underlying substrate.

9.
J Med Chem ; 67(6): 4757-4781, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38466654

RESUMO

The high lethality of Staphylococcus aureus infections and the emergence of antibiotic resistance make the development of new antibiotics urgent. Our previous work identified a hit compound h1 (AF-353) as a novel Mycobacterium tuberculosis (Mtb) dihydrofolate reductase (DHFR) inhibitor. Herein, we analyzed the antimicrobial profile of h1 and performed a comprehensive structure-activity relationship (SAR) assay based on h1. The representative compound j9 exhibited potent antibacterial activity against S. aureus without cross-resistance to other antimicrobial classes. Multiple genetic and biochemical approaches showed that j9 directly binds to SaDHFR, resulting in strong inhibition of its enzymatic activity (IC50 = 0.97 nM). Additionally, j9 had an acceptable in vivo safety profile and oral bioavailability (F = 40.7%) and also showed favorable efficacy in a mouse model of methicillin-resistant S. aureus (MRSA) skin infection. Collectively, these findings identified j9 as a novel SaDHFR inhibitor with the potential to combat drug-resistant S. aureus infections.


Assuntos
Antagonistas do Ácido Fólico , Staphylococcus aureus Resistente à Meticilina , Éteres Fenílicos , Pirimidinas , Infecções Estafilocócicas , Animais , Camundongos , Staphylococcus aureus , Antagonistas do Ácido Fólico/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana
10.
Phytomedicine ; 128: 155423, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38518646

RESUMO

BACKGROUND: Polycystic ovary syndrome is a metabolic and hormonal disorder that is closely linked to oxidative stress. Within individuals diagnosed with PCOS, changes occur in the ovaries, resulting in an excessive buildup of iron and peroxidation of lipids, both of which may be associated with the occurrence of ferroptosis. Baicalein, a flavonoid found in the roots of Scutellaria baicalensis and widely known as Chinese skullcap, is known for its anti-inflammatory and anti-ferroptotic properties, which protect against various diseases. Nevertheless, there has been no investigation into the impact of baicalein on polycystic ovary syndrome. PURPOSE: This study aimed to correlate ferroptosis with polycystic ovary syndrome and to assess the effects of baicalein on ovarian dysfunction and placental development in pregnant patients. STUDY DESIGN AND METHODS: Polycystic ovary syndrome was induced in a rat model through the administration of dehydroepiandrosterone, and these rats were treated with baicalein. Oxidative stress and inflammation levels were assessed in serum and ovaries, and tissue samples were collected for histological and protein analyses. Furthermore, different groups of female rats were mated with male rats to observe pregnancy outcomes and tissue samples were obtained for histological, protein, and RNA sequencing. Then, RNA sequencing of the placenta was performed to determine the key genes involved in ferroptosis negative regulation (FNR) signatures. RESULTS: Baicalein was shown to reduce ovarian oxidative stress and pathology. Baicalein also ameliorated polycystic ovary syndrome by decreasing lipid peroxidation and chronic inflammation and modulating mitochondrial functions and ferroptosis in the ovaries. Specifically, glutathione peroxidase and ferritin heavy chain 1 were considerably downregulated in polycystic ovary syndrome gravid rats compared to their expression in the control group, and most of these differences were reversed after baicalein intervention. CONCLUSIONS: Our findings, initially, indicated that baicalein could potentially enhance the prognosis of individuals suffering from polycystic ovary syndrome by reducing oxidative stress and ferroptosis, thus potentially influencing the formulation of a therapeutic approach to address this condition.

11.
Infect Drug Resist ; 17: 1011-1019, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505250

RESUMO

Purpose: Plastic bronchitis (PB), a rare complication of respiratory infection characterized by the formation of casts in the tracheobronchial tree, can lead to airway obstruction and severe condition. Adenovirus is one of the common pathogens of PB caused by infection. This study aimed to evaluate the clinical features and risk factors for PB in children with severe adenovirus pneumonia. Methods: A retrospective study of children with severe adenovirus pneumonia with bronchoscopy results at Guangzhou Women and Children's Hospital between January 2018 and January 2020 was performed. Based on bronchoscopy, we divided children with severe adenovirus pneumonia into two groups: PB and non-PB. Binary logistic regression analysis was used to identify independent risk factors for PB in patients with severe adenovirus pneumonia after univariate analysis. Results: Our study examined 156 patients with severe adenovirus pneumonia with bronchoscopy results in hospital. Among them, 18 developed PB and 138 did not. On multivariate analysis, the independent risk factors of PB in children with severe adenovirus pneumonia were history of allergies (OR 10.147, 95% CI 1.727-59.612; P=0.010), diminished breath sounds (OR 12.856, 95% CI 3.259-50.713; P=0.001), and increased proportion of neutrophils (>70%; OR 8.074, 95% CI 1.991-32.735; P=0.003). Conclusion: Children with severe adenovirus pneumonia with a history of allergies, diminished breath sounds, and increased the proportion of neutrophils >70% may show higher risk of PB.

12.
Heliyon ; 10(6): e27314, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38509886

RESUMO

Purpose: This study aimed to quantitatively evaluate the whitening process of brown adipose tissue (BAT) in mice using synthetic magnetic resonance imaging (SyMRI) and analyzed the correlation between SyMRI quantitative measurements of BAT and serum lipid profiles. Methods: Fifteen C57BL/6 mice were divided into three groups and fed different diets as follows: normal chow diet for 12 weeks, NCD group; high-fat diet (HFD) for 12 weeks, HFD-12w group; and HFD for 36 weeks, HFD-36w group. Mice were scanned using 3.0 T SyMRI. T1 and T2 values of BAT and interscapular BAT (iBAT) volume were measured. After sacrifice, the body weight of mice, lipid profiles, BAT morphology, and uncoupling protein 1 (UCP1) levels were determined. Statistical analysis was performed using one-way analysis of variance or Kruskal-Wallis test followed by Bonferroni correction for pairwise comparisons. Bonferroni-adjusted significance level was set at P < 0.017 (alpha: 0.05/3 = 0.017). Results: T2 values of BAT in the HFD-12w group were significantly higher than those in the NCD group (P < 0.001), and those in the HFD-36w group were significantly higher than those in the other two groups (both P < 0.001). The iBAT volume in the HFD-36w group was significantly higher than that in the HFD-12w (P = 0.013) and NCD groups (P = 0.005). T2 values of BAT and iBAT volume were significantly correlated with serum lipid profiles and mouse body weight. Conclusions: SyMRI can noninvasively evaluate the whitening process of BAT using T2 values and iBAT volume, thereby facilitating the visualization of the whitening process.

13.
JACC Basic Transl Sci ; 9(2): 203-219, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38510716

RESUMO

The epicardium provides epicardial-derived cells and molecular signals to support cardiac development and regeneration. Zebrafish and mouse studies have shown that ccm2, a cerebral cavernous malformation disease gene, is essential for cardiac development. Endocardial cell-specific deletion of Ccm2 in mice has previously established that Ccm2 is essential for maintenance of the cardiac jelly for cardiac development during early gestation. The current study aimed to explore the function of Ccm2 in epicardial cells for heart development and regeneration. Through genetic deletion of Ccm2 in epicardial cells, our in vivo and ex vivo experiments revealed that Ccm2 is required by epicardial cells to support heart development. Ccm2 regulates epicardial cell adhesion, cell polarity, cell spreading, and migration. Importantly, the loss of Ccm2 in epicardial cells delays cardiac function recovery and aggravates cardiac fibrosis following myocardial infarction. Molecularly, Ccm2 targets the production of cytoskeletal and matrix proteins to maintain epicardial cell function and behaviors. Epicardial Ccm2 plays a critical role in heart development and regeneration via its regulation of cytoskeleton reorganization.

14.
Int J Surg ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38445459

RESUMO

BACKGROUND: Occult peritoneal metastases (OPM) in patients with pancreatic ductal adenocarcinoma (PDAC) are frequently overlooked during imaging. We aimed to develop and validate a CT-based deep learning-based radiomics (DLR) model to identify OPM in PDAC before treatment. METHODS: This retrospective, bicentric study included 302 patients with PDAC (training: n=167, OPM-positive, n=22; internal test: n=72, OPM-positive, n=9: external test, n=63, OPM-positive, n=9) who had undergone baseline CT examinations between January 2012 and October 2022. Handcrafted radiomics (HCR) and DLR features of the tumor and HCR features of peritoneum were extracted from CT images. Mutual information and least absolute shrinkage and selection operator algorithms were used for feature selection. A combined model, which incorporated the selected clinical-radiological, HCR, and DLR features, was developed using a logistic regression classifier using data from the training cohort and validated in the test cohorts. RESULTS: Three clinical-radiological characteristics (carcinoembryonic antigen 19-9 and CT-based T and N stages), nine HCR features of the tumor, 14 DLR features of the tumor and three HCR features of the peritoneum were retained after feature selection. The combined model yielded satisfactory predictive performance, with an area under the curve (AUC) of 0.853 (95% confidence interval [CI], 0.790-0.903), 0.845 (95% CI, 0.740-0.919), and 0.852 (95% CI, 0.740-0.929) in the training, internal test, and external test cohorts, respectively (all P<0.05). The combined model showed better discrimination than the clinical-radiological model in the training (AUC=0.853 vs. 0.612, P<0.001) and the total test (AUC=0.842 vs. 0.638, P<0.05) cohorts. The decision curves revealed that the combined model had greater clinical applicability than the clinical-radiological model. CONCLUSIONS: The model combining CT-based deep learning radiomics and clinical-radiological features showed satisfactory performance for predicting occult peritoneal metastases in patients with pancreatic ductal adenocarcinoma.

15.
iScience ; 27(2): 108876, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38313049

RESUMO

SurE, the first reported penicillin-binding protein-like thioesterase (PBP-like TE), is known as a new off-loading cyclase, which catalyzes heterochiral coupling in nonribosomal peptides (NRPs). However, the structural rationale for substrate stereoselectivity and enzymatic mechanism remains mysterious. Here, computational models, integrating MD simulations and QM/MM methods, unveiled SurE's substrate recognition and catalytic process. An oxyanion hole stabilized the C-terminal D-residue during recognition. Residue R446 anchored the substrate for macrocyclization. A vital hydrogen-bonding network (Y154, K66, N156), verified by mutation results, was responsible for the recognition of N-terminal L-residue and involvement in catalytic process with a calculated 19.4 kcal/mol energy barrier. Four novel-designed peptide precursors were effectively cyclized into cyclopeptides by SurE based on computational analysis. Our results provide a comprehensive understanding of SurE's catalytic mechanism and guiding design of versatile PBP-like TEs for novel macrocyclic NRPs.

16.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338931

RESUMO

Cladosporium, a genus of ascomycete fungi in the Dematiaceae family, is primarily recognized as a widespread environmental saprotrophic fungus or plant endophyte. Further research has shown that the genus is distributed in various environments, particularly in marine ecosystems, such as coral reefs, mangroves and the polar region. Cladosporium, especially the marine-derived Cladosporium, is a highly resourceful group of fungi whose natural products have garnered attention due to their diverse chemical structures and biological activities, as well as their potential as sources of novel leads to compounds for drug production. This review covers the sources, distribution, bioactivities, biosynthesis and structural characteristics of compounds isolated from Cladosporium in the period between January 2000 and December 2022, and conducts a comparative analysis of the Cladosporium isolated compounds derived from marine and terrestrial sources. Our results reveal that 34% of Cladosporium-derived natural products are reported for the first time. And 71.79% of the first reported compounds were isolated from marine-derived Cladosporium. Cladosporium-derived compounds exhibit diverse skeletal chemical structures, concentrating in the categories of polyketides (48.47%), alkaloids (19.21%), steroids and terpenoids (17.03%). Over half of the natural products isolated from Cladosporium have been found to have various biological activities, including cytotoxic, antibacterial, antiviral, antifungal and enzyme-inhibitory activities. These findings testify to the tremendous potential of Cladosporium, especially the marine-derived Cladosporium, to yield novel bioactive natural products, providing a structural foundation for the development of new drugs.


Assuntos
Produtos Biológicos , Cladosporium , Produtos Biológicos/farmacologia , Ecossistema , Estudos Prospectivos , Fungos
17.
Lancet ; 403(10433): 1241-1253, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38367641

RESUMO

BACKGROUND: Infants and young children born prematurely are at high risk of severe acute lower respiratory infection (ALRI) caused by respiratory syncytial virus (RSV). In this study, we aimed to assess the global disease burden of and risk factors for RSV-associated ALRI in infants and young children born before 37 weeks of gestation. METHODS: We conducted a systematic review and meta-analysis of aggregated data from studies published between Jan 1, 1995, and Dec 31, 2021, identified from MEDLINE, Embase, and Global Health, and individual participant data shared by the Respiratory Virus Global Epidemiology Network on respiratory infectious diseases. We estimated RSV-associated ALRI incidence in community, hospital admission, in-hospital mortality, and overall mortality among children younger than 2 years born prematurely. We conducted two-stage random-effects meta-regression analyses accounting for chronological age groups, gestational age bands (early preterm, <32 weeks gestational age [wGA], and late preterm, 32 to <37 wGA), and changes over 5-year intervals from 2000 to 2019. Using individual participant data, we assessed perinatal, sociodemographic, and household factors, and underlying medical conditions for RSV-associated ALRI incidence, hospital admission, and three severity outcome groups (longer hospital stay [>4 days], use of supplemental oxygen and mechanical ventilation, or intensive care unit admission) by estimating pooled odds ratios (ORs) through a two-stage meta-analysis (multivariate logistic regression and random-effects meta-analysis). This study is registered with PROSPERO, CRD42021269742. FINDINGS: We included 47 studies from the literature and 17 studies with individual participant-level data contributed by the participating investigators. We estimated that, in 2019, 1 650 000 (95% uncertainty range [UR] 1 350 000-1 990 000) RSV-associated ALRI episodes, 533 000 (385 000-730 000) RSV-associated hospital admissions, 3050 (1080-8620) RSV-associated in-hospital deaths, and 26 760 (11 190-46 240) RSV-attributable deaths occurred in preterm infants worldwide. Among early preterm infants, the RSV-associated ALRI incidence rate and hospitalisation rate were significantly higher (rate ratio [RR] ranging from 1·69 to 3·87 across different age groups and outcomes) than for all infants born at any gestational age. In the second year of life, early preterm infants and young children had a similar incidence rate but still a significantly higher hospitalisation rate (RR 2·26 [95% UR 1·27-3·98]) compared with all infants and young children. Although late preterm infants had RSV-associated ALRI incidence rates similar to that of all infants younger than 1 year, they had higher RSV-associated ALRI hospitalisation rate in the first 6 months (RR 1·93 [1·11-3·26]). Overall, preterm infants accounted for 25% (95% UR 16-37) of RSV-associated ALRI hospitalisations in all infants of any gestational age. RSV-associated ALRI in-hospital case fatality ratio in preterm infants was similar to all infants. The factors identified to be associated with RSV-associated ALRI incidence were mainly perinatal and sociodemographic characteristics, and factors associated with severe outcomes from infection were mainly underlying medical conditions including congenital heart disease, tracheostomy, bronchopulmonary dysplasia, chronic lung disease, or Down syndrome (with ORs ranging from 1·40 to 4·23). INTERPRETATION: Preterm infants face a disproportionately high burden of RSV-associated disease, accounting for 25% of RSV hospitalisation burden. Early preterm infants have a substantial RSV hospitalisation burden persisting into the second year of life. Preventive products for RSV can have a substantial public health impact by preventing RSV-associated ALRI and severe outcomes from infection in preterm infants. FUNDING: EU Innovative Medicines Initiative Respiratory Syncytial Virus Consortium in Europe.


Assuntos
Pneumonia , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Lactente , Criança , Recém-Nascido , Humanos , Pré-Escolar , Recém-Nascido Prematuro , Carga Global da Doença , Infecções Respiratórias/epidemiologia , Hospitalização , Infecções por Vírus Respiratório Sincicial/epidemiologia , Fatores de Risco
19.
J R Soc Med ; : 1410768231223584, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345538

RESUMO

OBJECTIVES: We undertook a national analysis to characterise and identify risk factors for acute respiratory infections (ARIs) resulting in hospitalisation during the winter period in Scotland. DESIGN: A population-based retrospective cohort analysis. SETTING: Scotland. PARTICIPANTS: The study involved 5.4 million residents in Scotland. MAIN OUTCOME MEASURES: Cox proportional hazard models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the association between risk factors and ARI hospitalisation. RESULTS: Between 1 September 2022 and 31 January 2023, there were 22,284 (10.9% of 203,549 with any emergency hospitalisation) ARI hospitalisations (1759 in children and 20,525 in adults) in Scotland. Compared with the reference group of children aged 6-17 years, the risk of ARI hospitalisation was higher in children aged 3-5 years (aHR = 4.55; 95% CI: 4.11-5.04). Compared with those aged 25-29 years, the risk of ARI hospitalisation was highest among the oldest adults aged ≥80 years (aHR = 7.86; 95% CI: 7.06-8.76). Adults from more deprived areas (most deprived vs. least deprived, aHR = 1.64; 95% CI: 1.57-1.72), with existing health conditions (≥5 vs. 0 health conditions, aHR = 4.84; 95% CI: 4.53-5.18) or with history of all-cause emergency admissions (≥6 vs. 0 previous emergency admissions, aHR = 7.53; 95% CI: 5.48-10.35) were at a higher risk of ARI hospitalisations. The risk increased by the number of existing health conditions and previous emergency admission. Similar associations were seen in children. CONCLUSIONS: Younger children, older adults, those from more deprived backgrounds and individuals with greater numbers of pre-existing conditions and previous emergency admission were at increased risk for winter hospitalisations for ARI.

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