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1.
J Biol Chem ; 299(8): 105034, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37442233

RESUMO

Lung branching morphogenesis relies on a complex coordination of multiple signaling pathways and transcription factors. Here, we found that ablation of the LIM homeodomain transcription factor Islet1 (Isl1) in lung epithelium resulted in defective branching morphogenesis and incomplete formation of five lobes. A reduction in mesenchymal cell proliferation was observed in Isl1ShhCre lungs. There was no difference in apoptosis between the wild-type (ShhCre) and Isl1ShhCre embryos. RNA-Seq and in situ hybridization analysis showed that Shh, Ptch1, Sox9, Irx1, Irx2, Tbx2, and Tbx3 were downregulated in the lungs of Isl1ShhCre embryos. ChIP assay implied the Shh gene served as a direct target of ISL1, since the transcription factor ISL1 could bind to the Shh epithelial enhancer sequence (MACS1). Also, activation of the Hedgehog pathway via ectopic gene expression rescued the defects caused by Isl1 ablation, confirming the genetic integration of Hedgehog signaling. In conclusion, our works suggest that epithelial Isl1 regulates lung branching morphogenesis through administrating the Shh signaling mediated epithelial-mesenchymal communications.


Assuntos
Proteínas Hedgehog , Pulmão , Fatores de Transcrição , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Pulmão/crescimento & desenvolvimento , Pulmão/metabolismo , Morfogênese , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Camundongos
2.
Eur Respir J ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38387969

RESUMO

BACKGROUND: This study aimed to evaluate the longitudinal progression of residual lung abnormalities (ground-glass opacities, reticulations, and fibrotic-like changes) and pulmonary function, three years following coronavirus disease 2019(COVID-19). METHODS: This prospective, longitudinal cohort study enrolled COVID-19 survivors who exhibited residual lung abnormalities upon discharge from two hospitals. Follow-up assessments were conducted at 6 months, 12 months, 2 years, and 3 years post-discharge, and included pulmonary function tests, 6-minute walk distance (6MWD), chest CT scans, and symptom questionnaires. Non-COVID-19 controls were retrospectively recruited for comparative analysis. RESULTS: 728 COVID-19 survivors and 792 controls were included. From 6 months to 3 years, there was a gradual improvement in reduced diffusing capacity of the lungs for carbon monoxide (DLCO<80% predicted, 49% versus 38%, p=0.001), 6MWD (496 m versus 510 m, p=0.002) and residual lung abnormalities(46% versus 36%, p<0.001), regardless of the disease severity. Patients with residual lung abnormalities at 3 years more commonly had respiratory symptoms (32% versus 16%, p<0.001), lower 6MWD (494 m versus 510 m, p=0.003), and abnormal DLCO (57% versus 27%, p<0.001) compared to those with complete resolution. Compared to the controls, the proportion of DLCO impairment (38% versus 17%, p<0.001) and respiratory symptoms (23% versus 2.2%, p<0.001) were significantly higher in the matched COVID-19 survivors at the 3-year follow-up. CONCLUSIONS: Most patients exhibited improvement in radiological abnormalities and pulmonary function over time following COVID-19. However, more than one-third continued to have persistent lung abnormalities at the 3-year mark, which were associated with respiratory symptoms and reduced diffusion capacity.

3.
BMC Cancer ; 24(1): 223, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365678

RESUMO

BACKGROUND: The prognostic significance of the CRAFITY score (CRP and AFP in ImmunoTherapY) has been demonstrated in hepatocellular carcinoma (HCC) patients receiving immunotherapy. The purpose of this study was to investigate the utility and the predictive value of CRAFITY score in HCC after transarterial chemoembolization (TACE) in combination with tyrosine kinase inhibitors (TKIs) and immunotherapy. MATERIALS AND METHODS: Data from patients with advanced HCC treated with TACE plus TKIs and PD-1 inhibitor from January 2019 to June 2022 were collected and analyzed retrospectively. Patients with AFP ≥ 100 ng/mL and those with CRP ≥ 1 mg/dL were assigned a CRAFITY score of 1 point. Patients were divided into three groups according to their CRAFITY score (CRAFITY-low, 0 points; CRAFITY-intermediate, 1 point; and CRAFITY-high, 2 points). The differences in overall survival (OS), progression-free survival (PFS) and adverse events (AEs) were compared among the three groups. Tumor response was evaluated at 3, 6 and 12 months after the first combination treatment. Risk factors for OS and PFS were assessed. RESULTS: A total of 70 patients were included. The patients were assigned CRAFITY scores of 0 points (CRAFITY-low, n = 25 [35.71%]), 1 point (CRAFITY-intermediate, n = 29 [41.42%]), and 2 points (CRAFITY-high, n = 16 [22.81%]). Multivariate analysis showed that lower CRAFITY score was an independent factor for the improved OS (P =.045) and PFS (P <.001). TACE session was also associated with the OS (P =.048) in the multivariate analysis. The CRAFITY-low cohort achieved a higher objective response rate (ORR) at the 3-month evaluation of tumor response. However, there was no significant difference in ORR and disease control rate (DCR) observed at the 6-month follow-up. DCR showed a statistically significant difference among three groups during the 12-month follow-up period. The percentage of patients with protein urea was highest in the CRAFITY-high group. No significance differences were observed in grade ≥ 3 AEs in three groups. CONCLUSION: The CRAFITY score is simple and could be useful for predicting treatment outcomes, tumor response and AEs of the HCC patients receiving TACE plus TKIs and PD-1 inhibitor therapy.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/terapia , Inibidores de Checkpoint Imunológico , Estudos Retrospectivos , alfa-Fetoproteínas
4.
Eur Radiol ; 34(4): 2716-2726, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37736804

RESUMO

OBJECTIVES: To investigate if delta-radiomics features have the potential to predict the major pathological response (MPR) to neoadjuvant chemoimmunotherapy in non-small cell lung cancer (NSCLC) patients. METHODS: Two hundred six stage IIA-IIIB NSCLC patients from three institutions (Database1 = 164; Database2 = 21; Database3 = 21) who received neoadjuvant chemoimmunotherapy and surgery were included. Patients in Database1 were randomly assigned to the training dataset and test dataset, with a ratio of 0.7:0.3. Patients in Database2 and Database3 were used as two independent external validation datasets. Contrast-enhanced CT scans were obtained at baseline and before surgery. The delta-radiomics features were defined as the relative net change of radiomics features between baseline and preoperative. The delta-radiomics model and pre-treatment radiomics model were established. The performance of Immune-Related Response Evaluation Criteria in Solid Tumors (iRECIST) for predicting MPR was also evaluated. RESULTS: Half of the patients (106/206, 51.5%) showed MPR after neoadjuvant chemoimmunotherapy. For predicting MPR, the delta-radiomics model achieved a satisfying area under the curves (AUCs) values of 0.768, 0.732, 0.833, and 0.716 in the training, test, and two external validation databases, respectively, which showed a superior predictive performance than the pre-treatment radiomics model (0.644, 0.616, 0.475, and 0.608). Compared with iRECIST criteria (0.624, 0.572, 0.650, and 0.466), a mixed model that combines delta-radiomics features and iRECIST had higher AUC values for MPR prediction of 0.777, 0.761, 0.850, and 0.670 in four sets. CONCLUSION: The delta-radiomics model demonstrated superior diagnostic performance compared to pre-treatment radiomics model and iRECIST criteria in predicting MPR preoperatively in neoadjuvant chemoimmunotherapy for stage II-III NSCLC. CLINICAL RELEVANCE STATEMENT: Delta-radiomics features based on the relative net change of radiomics features between baseline and preoperative CT scans serve a vital support tool in accurately identifying responses to neoadjuvant chemoimmunotherapy, which can help physicians make more appropriate treatment decisions. KEY POINTS: • The performances of pre-treatment radiomics model and iRECIST model in predicting major pathological response of neoadjuvant chemoimmunotherapy were unsatisfactory. • The delta-radiomics features based on relative net change of radiomics features between baseline and preoperative CT scans may be used as a noninvasive biomarker for predicting major pathological response of neoadjuvant chemoimmunotherapy. • Combining delta-radiomics features and iRECIST can further improve the predictive performance of responses to neoadjuvant chemoimmunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Área Sob a Curva , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Terapia Neoadjuvante , Radiômica , Estudos Retrospectivos
5.
Inorg Chem ; 63(5): 2745-2755, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38241145

RESUMO

Hematite (α-Fe2O3) photoanode is a promising candidate for efficient PEC solar energy conversion. However, the serious charge recombination together with the sluggish water oxidation kinetics of α-Fe2O3 still restricts its practical application in renewable energy systems. In this work, a CoOOH/α-Fe2O3/SnO2 photoanode was fabricated, in which the ultrathin SnO2 underlayer is deposited on the fluorine-doped tin oxide (FTO) substrate, α-Fe2O3 nanorod array is the absorber layer, and CoOOH nanosheet is the surface modifier, respectively. The resulting CoOOH/α-Fe2O3/SnO2 exhibited excellent PEC water splitting with a high photocurrent density of 2.05 mA cm-2 at 1.23 V vs RHE in the alkaline electrolyte, which is ca. 3.25 times that of bare α-Fe2O3. PEC characterizations demonstrated that SnO2 not only could block hole transport from α-Fe2O3 to FTO substrate but also could efficiently enhance the light-harvesting property and reduce the surface states by controlling the growth process of α-Fe2O3, while the CoOOH overlayer as cocatalysts could rapidly extract the photogenerated holes and provide catalytic active sites for water oxidation. Benefiting from the synergistic effects of SnO2 and CoOOH, the efficiency of the charge recombination and the overpotential for water oxidation of α-Fe2O3 are obviously decreased, resulting in the boosted PEC efficiency for water oxidation. The rational design and simple fabrication strategy display great potentials to be used for other PEC systems with excellent efficiency.

6.
Environ Sci Technol ; 58(14): 6149-6157, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38556993

RESUMO

The global management for persistent, mobile, and toxic (PMT) and very persistent and very mobile (vPvM) substances has been further strengthened with the rapid increase of emerging contaminants. The development of a ready-to-use and publicly available tool for the high-throughput screening of PMT/vPvM substances is thus urgently needed. However, the current model building with the coupling of conventional algorithms, small-scale data set, and simplistic features hinders the development of a robust model for screening PMT/vPvM with wide application domains. Here, we construct a graph convolutional network (GCN)-enhanced model with feature fusion of a molecular graph and molecular descriptors to effectively utilize the significant correlation between critical descriptors and PMT/vPvM substances. The model is built with 213,084 substances following the latest PMT classification criteria. The application domains of the GCN-enhanced model assessed by kernel density estimation demonstrate the high suitability for high-throughput screening PMT/vPvM substances with both a high accuracy rate (86.6%) and a low false-negative rate (6.8%). An online server named PMT/vPvM profiler is further developed with a user-friendly web interface (http://www.pmt.zj.cn/). Our study facilitates a more efficient evaluation of PMT/vPvM substances with a globally accessible screening platform.


Assuntos
Algoritmos , Ensaios de Triagem em Larga Escala
7.
Can J Physiol Pharmacol ; 102(2): 105-115, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979203

RESUMO

Previous studies from our laboratory revealed that the gaseous molecule hydrogen sulfide (H2S), a metabolic product of epigenetics, involves trans-sulfuration pathway for ensuring metabolism and clearance of homocysteine (Hcy) from body, thereby mitigating the skeletal muscle's pathological remodeling. Although the master circadian clock regulator that is known as brain and muscle aryl hydrocarbon receptor nuclear translocator like protein 1 (i.e., BMAL 1) is associated with S-adenosylhomocysteine hydrolase (SAHH) and Hcy metabolism but how trans-sulfuration pathway is influenced by the circadian clock remains unexplored. We hypothesize that alterations in the functioning of circadian clock during sleep and wake cycle affect skeletal muscle's biology. To test this hypothesis, we measured serum matrix metalloproteinase (MMP) activities using gelatin gels for analyzing the MMP-2 and MMP-9. Further, employing casein gels, we also studied MMP-13 that is known to be influenced by the growth arrest and DNA damage-45 (GADD45) protein during sleep and wake cycle. The wild type and cystathionine ß synthase-deficient (CBS-/+) mice strains were treated with H2S and subjected to measurement of trans-sulfuration factors from skeletal muscle tissues. The results suggested highly robust activation of MMPs in the wake mice versus sleep mice, which appears somewhat akin to the "1-carbon metabolic dysregulation", which takes place during remodeling of extracellular matrix during muscular dystrophy. Interestingly, the levels of trans-sulfuration factors such as CBS, cystathionine γ lyase (CSE), methyl tetrahydrofolate reductase (MTHFR), phosphatidylethanolamine N-methyltransferase (PEMT), and Hcy-protein bound paraoxonase 1 (PON1) were attenuated in CBS-/+ mice. However, treatment with H2S mitigated the attenuation of the trans-sulfuration pathway. In addition, levels of mitochondrial peroxisome proliferator-activated receptor-gamma coactivator 1-α (PGC 1-α) and mitofusin-2 (MFN-2) were significantly improved by H2S intervention. Our findings suggest participation of the circadian clock in trans-sulfuration pathway that affects skeletal muscle remodeling and mitochondrial regeneration.


Assuntos
Relógios Circadianos , Sulfeto de Hidrogênio , Animais , Camundongos , Sulfeto de Hidrogênio/metabolismo , Cistationina beta-Sintase , Músculo Esquelético/metabolismo , Géis , Cistationina gama-Liase/metabolismo , Fosfatidiletanolamina N-Metiltransferase
8.
Molecules ; 29(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338395

RESUMO

A new bergamotane sesquiterpenoid, named xylariterpenoid H (1), along with fourteen known compounds (2-15), were isolated from the crude extract of Aspergillus fumigatus, an endophytic fungus isolated from Delphinium grandiflorum L. Their structures were elucidated mainly by extensive analyses of NMR and MS spectroscopic data. In addition, the screening results of antibacterial and cytotoxic activities of compounds 1-15 showed that compound 4 displayed antibacterial activities against Staphylococcus aureus and MRSA (methicillin-resistant S. aureus) with an MIC value of 3.12 µg/mL.


Assuntos
Aspergillus fumigatus , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Estrutura Molecular , Antibacterianos/química , Fungos
9.
Angew Chem Int Ed Engl ; 63(6): e202313260, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37938169

RESUMO

Conjugated polymers that can efficiently transport both ionic and electronic charges have broad applications in next-generation optoelectronic, bioelectronic, and energy storage devices. To date, almost all the conjugated polymers have hydrophobic backbones, which impedes efficient ion diffusion/transport in aqueous media. Here, we design and synthesize a novel hydrophilic polymer building block, 4a-azonia-naphthalene (AN), drawing inspiration from biological systems. Because of the strong electron-withdrawing ability of AN, the AN-based polymers show typical n-type charge transport behaviors. We find that cationic aromatics exhibit strong cation-π interactions, leading to smaller π-π stacking distance, interesting ion diffusion behavior, and good morphology stability. Additionally, AN enhances the hydrophilicity and ionic-electronic coupling of the polymer, which can help to improve ion diffusion/injection speed, and operational stability of organic electrochemical transistors (OECTs). The integration of cationic building blocks will undoubtedly enrich the material library for high-performance n-type conjugated polymers.

10.
Radiology ; 307(2): e222888, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36786698

RESUMO

Background Information on pulmonary sequelae and pulmonary function 2 years after recovery from SARS-CoV-2 infection is lacking. Purpose To longitudinally assess changes in chest CT abnormalities and pulmonary function in individuals after SARS-CoV-2 infection. Materials and Methods In this prospective study, participants discharged from the hospital after SARS-CoV-2 infection from January 20 to March 10, 2020, were considered for enrollment. Participants without chest CT scans at admission or with complete resolution of lung abnormalities at discharge were excluded. Serial chest CT scans and pulmonary function test results were obtained 6 months (June 20 to August 31, 2020), 12 months (December 20, 2020, to February 3, 2021), and 2 years (November 16, 2021, to January 10, 2022) after symptom onset. The term interstitial lung abnormality (ILA) and two subcategories, fibrotic ILAs and nonfibrotic ILAs, were used to describe residual CT abnormalities on follow-up CT scans. Differences between groups were compared with the χ2 test, Fisher exact test, or independent samples t test. Results Overall, 144 participants (median age, 60 years [range, 27-80 years]; 79 men) were included. On 2-year follow-up CT scans, 39% of participants (56 of 144) had ILAs, including 23% (33 of 144) with fibrotic ILAs and 16% (23 of 144) with nonfibrotic ILAs. The remaining 88 of 144 participants (61%) showed complete radiologic resolution. Over 2 years, the incidence of ILAs gradually decreased (54%, 42%, and 39% of participants at 6 months, 12 months, and 2 years, respectively; P < .001). Respiratory symptoms (34% vs 15%, P = .007) and abnormal diffusing capacity of lung for carbon monoxide (43% vs 20%, P = .004) occurred more frequently in participants with ILAs than in those with complete radiologic resolution. Conclusion More than one-third of participants had persistent interstitial lung abnormalities 2 years after COVID-19 infection, which were associated with respiratory symptoms and decreased diffusion pulmonary function. Chinese Clinical Trial Registry no. ChiCTR2000038609 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by van Beek in this issue.


Assuntos
COVID-19 , Humanos , Masculino , Pessoa de Meia-Idade , COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Estudos Prospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X/métodos
11.
Mol Cell Biochem ; 478(1): 103-119, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35731343

RESUMO

The ongoing pandemic (also known as coronavirus disease-19; COVID-19) by a constantly emerging viral agent commonly referred as the severe acute respiratory syndrome corona virus 2 or SARS-CoV-2 has revealed unique pathological findings from infected human beings, and the postmortem observations. The list of disease symptoms, and postmortem observations is too long to mention; however, SARS-CoV-2 has brought with it a whole new clinical syndrome in "long haulers" including dyspnea, chest pain, tachycardia, brain fog, exercise intolerance, and extreme fatigue. We opine that further improvement in delivering effective treatment, and preventive strategies would be benefited from validated animal disease models. In this context, we designed a study, and show that a genetically engineered mouse expressing the human angiotensin converting enzyme 2; ACE-2 (the receptor used by SARS-CoV-2 agent to enter host cells) represents an excellent investigative resource in simulating important clinical features of the COVID-19. The ACE-2 mouse model (which is susceptible to SARS-CoV-2) when administered with a recombinant SARS-CoV-2 spike protein (SP) intranasally exhibited a profound cytokine storm capable of altering the physiological parameters including significant changes in cardiac function along with multi-organ damage that was further confirmed via histological findings. More importantly, visceral organs from SP treated mice revealed thrombotic blood clots as seen during postmortem examination. Thus, the ACE-2 engineered mouse appears to be a suitable model for studying intimate viral pathogenesis thus paving the way for identification, and characterization of appropriate prophylactics as well as therapeutics for COVID-19 management.


Assuntos
COVID-19 , Animais , Humanos , Camundongos , Modelos Animais de Doenças , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética
12.
Int J Mol Sci ; 24(8)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37108465

RESUMO

Renal denervation (RDN) protects against hypertension, hypertrophy, and heart failure (HF); however, it is not clear whether RDN preserves ejection fraction (EF) during heart failure (HFpEF). To test this hypothesis, we simulated a chronic congestive cardiopulmonary heart failure (CHF) phenotype by creating an aorta-vena cava fistula (AVF) in the C57BL/6J wild type (WT) mice. Briefly, there are four ways to create an experimental CHF: (1) myocardial infarction (MI), which is basically ligating the coronary artery by instrumenting and injuring the heart; (2) trans-aortic constriction (TAC) method, which mimics the systematic hypertension, but again constricts the aorta on top of the heart and, in fact, exposes the heart; (3) acquired CHF condition, promoted by dietary factors, diabetes, salt, diet, etc., but is multifactorial in nature; and finally, (4) the AVF, which remains the only one wherein AVF is created ~1 cm below the kidneys in which the aorta and vena cava share the common middle-wall. By creating the AVF fistula, the red blood contents enter the vena cava without an injury to the cardiac tissue. This model mimics or simulates the CHF phenotype, for example, during aging wherein with advancing age, the preload volume keeps increasing beyond the level that the aging heart can pump out due to the weakened cardiac myocytes. Furthermore, this procedure also involves the right ventricle to lung to left ventricle flow, thus creating an ideal condition for congestion. The heart in AVF transitions from preserved to reduced EF (i.e., HFpEF to HFrEF). In fact, there are more models of volume overload, such as the pacing-induced and mitral valve regurgitation, but these are also injurious models in nature. Our laboratory is one of the first laboratories to create and study the AVF phenotype in the animals. The RDN was created by treating the cleaned bilateral renal artery. After 6 weeks, blood, heart, and renal samples were analyzed for exosome, cardiac regeneration markers, and the renal cortex proteinases. Cardiac function was analyzed by echocardiogram (ECHO) procedure. The fibrosis was analyzed with a trichrome staining method. The results suggested that there was a robust increase in the exosomes' level in AVF blood, suggesting a compensatory systemic response during AVF-CHF. During AVF, there was no change in the cardiac eNOS, Wnt1, or ß-catenin; however, during RDN, there were robust increases in the levels of eNOS, Wnt1, and ß-catenin compared to the sham group. As expected in HFpEF, there was perivascular fibrosis, hypertrophy, and pEF. Interestingly, increased levels of eNOS suggested that despite fibrosis, the NO generation was higher and that it most likely contributed to pEF during HF. The RDN intervention revealed an increase in renal cortical caspase 8 and a decrease in caspase 9. Since caspase 8 is protective and caspase 9 is apoptotic, we suggest that RDN protects against the renal stress and apoptosis. It should be noted that others have demonstrated a role of vascular endothelium in preserving the ejection by cell therapy intervention. In the light of foregoing evidence, our findings also suggest that RDN is cardioprotective during HFpEF via preservation of the eNOS and accompanied endocardial-endothelial function.


Assuntos
Insuficiência Cardíaca , Hipertensão , Camundongos , Animais , Caspase 8 , Caspase 9 , beta Catenina , Volume Sistólico , Camundongos Endogâmicos C57BL , Rim/patologia , Miócitos Cardíacos/patologia , Hipertensão/patologia , Denervação , Hipertrofia/patologia , Fibrose
13.
Molecules ; 28(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37375408

RESUMO

Four examples of N,N-bis(aryl)butane-2,3-diimine-nickel(II) bromide complexes, [ArN=C(Me)-C(Me)=NAr]NiBr2 (where Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2 (Ni1), Ar = 2-(C6H11)-4,6-(CHPh2)2C6H2 (Ni2), 2-(C8H15)-4,6-(CHPh2)2C6H2 (Ni3) and 2-(C12H23)-4,6-(CHPh2)2C6H2 (Ni4)), disparate in the ring size of the ortho-cycloalkyl substituents, were prepared using a straightforward one-pot synthetic method. The molecular structures of Ni2 and Ni4 highlight the variation in the steric hindrance of the ortho-cyclohexyl and -cyclododecyl rings exerted on the nickel center, respectively. By employing EtAlCl2, Et2AlCl or MAO as activators, Ni1-Ni4 displayed moderate to high activity as catalysts for ethylene polymerization, with levels falling in the order Ni2 (cyclohexyl) > Ni1 (cyclopentyl) > Ni4 (cyclododecyl) > Ni3 (cyclooctyl). Notably, cyclohexyl-containing Ni2/MAO reached a peak level of 13.2 × 106 g(PE) of (mol of Ni)-1 h-1 at 40 °C, yielding high-molecular-weight (ca. 1 million g mol-1) and highly branched polyethylene elastomers with generally narrow dispersity. The analysis of polyethylenes with 13C NMR spectroscopy revealed branching density between 73 and 104 per 1000 carbon atoms, with the run temperature and the nature of the aluminum activator being influential; selectivity for short-chain methyl branches (81.8% (EtAlCl2); 81.1% (Et2AlCl); 82.9% (MAO)) was a notable feature. The mechanical properties of these polyethylene samples measured at either 30 °C or 60 °C were also evaluated and confirmed that crystallinity (Xc) and molecular weight (Mw) were the main factors affecting tensile strength and strain at break (εb = 353-861%). In addition, the stress-strain recovery tests indicated that these polyethylenes possessed good elastic recovery (47.4-71.2%), properties that align with thermoplastic elastomers (TPEs).

14.
Molecules ; 28(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38067579

RESUMO

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


Assuntos
Policetídeos , Trichoderma , Policetídeos/química , Estrutura Molecular , Trichoderma/química , Antifúngicos/química
15.
J Mol Cell Cardiol ; 162: 32-42, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34487754

RESUMO

Glucose metabolism comprises numerous amphibolic metabolites that provide precursors for not only the synthesis of cellular building blocks but also for ATP production. In this study, we tested how phosphofructokinase-1 (PFK1) activity controls the fate of glucose-derived carbon in murine hearts in vivo. PFK1 activity was regulated by cardiac-specific overexpression of kinase- or phosphatase-deficient 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase transgenes in mice (termed GlycoLo or GlycoHi mice, respectively). Dietary delivery of 13C6-glucose to these mice, followed by deep network metabolic tracing, revealed that low rates of PFK1 activity promote selective routing of glucose-derived carbon to the purine synthesis pathway to form 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR). Consistent with a mechanism of physical channeling, we found multimeric protein complexes that contained phosphoribosylaminoimidazole carboxylase (PAICS)-an enzyme important for AICAR biosynthesis, as well as chaperone proteins such as Hsp90 and other metabolic enzymes. We also observed that PFK1 influenced glucose-derived carbon deposition in glycogen, but did not affect hexosamine biosynthetic pathway activity. These studies demonstrate the utility of deep network tracing to identify metabolic channeling and changes in biosynthetic pathway activity in the heart in vivo and present new potential mechanisms by which metabolic branchpoint reactions modulate biosynthetic pathways.


Assuntos
Vias Biossintéticas , Fosfofrutoquinase-2 , Animais , Glucose/metabolismo , Glicólise , Camundongos , Miocárdio/metabolismo , Fosfofrutoquinase-1/metabolismo , Fosfofrutoquinase-2/metabolismo , Fosfofrutoquinases/metabolismo
16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(10): 1120-1123, 2022 Oct 10.
Artigo em Zh | MEDLINE | ID: mdl-36184096

RESUMO

OBJECTIVE: To explore the genetic basis for a patient presenting with renal insufficiency. METHODS: The patient was subjected to whole exome sequencing, and the candidate variant was verified by Sanger sequencing. Transcriptional activity of the PAX2 gene was analyzed by using a PRS4-EGFP reporter plasmid. RESULTS: Genetic testing revealed that the patient has carried a novel de novo heterozygous variant c.418C>T (p.Arg140Trp) of the PAX2 gene. The influence of c.389C>G (p.Pro130Arg), c.478G>A (p.Ala160Thr), c.418C>G (p. Arg140Gly) and c.418C>T (p.Arg140Trp) variants on the transcriptional activity was also evaluated. Functional study has illustrated that the PAX2-P130R, PAX2-R140G and PAX2-R140W variants all had a significant inhibitory effect on the transcriptional activity, but not the PAX2-A160T variant. CONCLUSION: The isolated renal hypoplasia of the proband is probably due to the likely pathogenic variant of the PAX2 gene.


Assuntos
Coloboma , Insuficiência Renal , Coloboma/genética , Testes Genéticos , Humanos , Mutação , Fator de Transcrição PAX2/genética , Insuficiência Renal/genética , Refluxo Vesicoureteral
17.
Bioorg Chem ; 109: 104736, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33640630

RESUMO

A series of novel phenazine derivatives (1~27) containing the Michael acceptor scaffolds were designed and synthesized in this study. Some compounds exhibited selective cytotoxicity against Bel-7402 cancer cell line in vitro, in which compound 26 were found to have the best antiproliferative activity. Meanwhile, compound 26 showed no obvious cell toxicity against human normal liver epithelial L02 cells, which means this compound possessed a better safety potential. In the following research, compound 26 was verified to inhibit TrxR1 enzyme activity, ultimately resulting in cellular molecular mechanism events of apoptosis including growth of intracellular ROS level, depletion of reduced Trx1, liberation of ASK1 and up-regulation of p38, respectively. Together, all these evidences implicated that compound 26 acted as the TrxR1 inhibitor against Bel-7402 cells, and could activate apoptosis through the ROS-Trx-ASK1-p38 pathway.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Fenazinas/farmacologia , Tiorredoxina Redutase 1/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Fenazinas/síntese química , Fenazinas/química , Relação Estrutura-Atividade , Tiorredoxina Redutase 1/metabolismo , Células Tumorais Cultivadas
18.
Mar Drugs ; 19(11)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34822491

RESUMO

Brown algae (Phaeophyceae) have been consumed by humans for hundreds of years. Current studies have shown that brown algae are rich sources of bioactive compounds with excellent nutritional value, and are considered functional foods with health benefits. Polysaccharides are the main constituents of brown algae; their diverse structures allow many unique physical and chemical properties that help to moderate a wide range of biological activities, including immunomodulation, antibacterial, antioxidant, prebiotic, antihypertensive, antidiabetic, antitumor, and anticoagulant activities. In this review, we focus on the major polysaccharide components in brown algae: the alginate, laminarin, and fucoidan. We explore how their structure leads to their health benefits, and their application prospects in functional foods and pharmaceuticals. Finally, we summarize the latest developments in applied research on brown algae polysaccharides.


Assuntos
Phaeophyceae/química , Polissacarídeos/farmacologia , Animais , Organismos Aquáticos , Alimento Funcional , Glucanos/química , Glucanos/farmacologia , Polissacarídeos/química
19.
Int J Mol Sci ; 22(24)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34948342

RESUMO

Although blood-heart-barrier (BHB) leakage is the hallmark of congestive (cardio-pulmonary) heart failure (CHF), the primary cause of death in elderly, and during viral myocarditis resulting from the novel coronavirus variants such as the severe acute respiratory syndrome novel corona virus 2 (SARS-CoV-2) known as COVID-19, the mechanism is unclear. The goal of this project is to determine the mechanism of the BHB in CHF. Endocardial endothelium (EE) is the BHB against leakage of blood from endocardium to the interstitium; however, this BHB is broken during CHF. Previous studies from our laboratory, and others have shown a robust activation of matrix metalloproteinase-9 (MMP-9) during CHF. MMP-9 degrades the connexins leading to EE dysfunction. We demonstrated juxtacrine coupling of EE with myocyte and mitochondria (Mito) but how it works still remains at large. To test whether activation of MMP-9 causes EE barrier dysfunction, we hypothesized that if that were the case then treatment with hydroxychloroquine (HCQ) could, in fact, inhibit MMP-9, and thus preserve the EE barrier/juxtacrine signaling, and synchronous endothelial-myocyte coupling. To determine this, CHF was created by aorta-vena cava fistula (AVF) employing the mouse as a model system. The sham, and AVF mice were treated with HCQ. Cardiac hypertrophy, tissue remodeling-induced mitochondrial-myocyte, and endothelial-myocyte contractions were measured. Microvascular leakage was measured using FITC-albumin conjugate. The cardiac function was measured by echocardiography (Echo). Results suggest that MMP-9 activation, endocardial endothelial leakage, endothelial-myocyte (E-M) uncoupling, dyssynchronous mitochondrial fusion-fission (Mfn2/Drp1 ratio), and mito-myocyte uncoupling in the AVF heart failure were found to be rampant; however, treatment with HCQ successfully mitigated some of the deleterious cardiac alterations during CHF. The findings have direct relevance to the gamut of cardiac manifestations, and the resultant phenotypes arising from the ongoing complications of COVID-19 in human subjects.


Assuntos
COVID-19/complicações , Insuficiência Cardíaca/metabolismo , Coração/virologia , Animais , Sangue/virologia , Fenômenos Fisiológicos Sanguíneos/imunologia , COVID-19/fisiopatologia , Cardiomegalia/metabolismo , Doenças Cardiovasculares/metabolismo , Fenômenos Fisiológicos Cardiovasculares/imunologia , Modelos Animais de Doenças , Endotélio/metabolismo , Coração/fisiopatologia , Insuficiência Cardíaca/virologia , Hidroxicloroquina/farmacologia , Masculino , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Musculares/metabolismo , Miocárdio/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Remodelação Ventricular/fisiologia
20.
Chembiochem ; 21(6): 865-873, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-31613042

RESUMO

Polymeric hydrogels with three-dimensional network structures have found tremendous applications in biomedicine. Herein, we report the synthesis of a multifunctional implant based on ovalbumin (OVA) as a carrier capable of synergistically delivering a photothermal transducing agent (polydopamine, PDA) to tumors. The formation of PDA was achieved by utilizing the basicity of OVA, whereas the formation of the hydrogel implant was achieved through the in vitro/in vivo near-infrared (NIR) laser-induced hyperthermia of PDA. The as-prepared PDA@OVA implant exhibits high photothermal conversion efficiency (38.7 %). Once implanted in vivo, the OVA-based implant shows great versatility in the treatment of malignant tumors. Furthermore, a chemotherapeutic (doxorubicin, DOX) and a contrast agent (iohexol), dispersed in the OVA solution in advance, can also be firmly entrapped in the hydrogel along with the hydrogel formation. It is anticipated that the multifunctional OVA-based implant, not showing any obvious toxicity to healthy tissue, could be a promising system for synergistic cancer treatment.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Hipertermia Induzida , Indóis/farmacologia , Iohexol/farmacologia , Ovalbumina/química , Fármacos Fotossensibilizantes/farmacologia , Terapia Fototérmica , Polímeros/farmacologia , Animais , Antibióticos Antineoplásicos/administração & dosagem , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indóis/administração & dosagem , Raios Infravermelhos , Iohexol/administração & dosagem , Camundongos , Camundongos Endogâmicos , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Imagem Óptica , Ovalbumina/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem , Polímeros/administração & dosagem , Microambiente Tumoral/efeitos dos fármacos
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