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1.
Proc Natl Acad Sci U S A ; 121(3): e2319335121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38198526

RESUMO

The phytohormone cytokinin has various roles in plant development, including meristem maintenance, vascular differentiation, leaf senescence, and regeneration. Prior investigations have revealed that cytokinin acts via a phosphorelay similar to the two-component system by which bacteria sense and respond to external stimuli. The eventual targets of this phosphorelay are type-B ARABIDOPSIS RESPONSE REGULATORS (B-ARRs), containing the conserved N-terminal receiver domain (RD), middle DNA binding domain (DBD), and C-terminal transactivation domain. While it has been established for two decades that the phosphoryl transfer from a specific histidyl residue in ARABIDOPSIS HIS PHOSPHOTRANSFER PROTEINS (AHPs) to an aspartyl residue in the RD of B-ARRs results in a rapid transcriptional response to cytokinin, the underlying molecular basis remains unclear. In this work, we determine the crystal structures of the RD-DBD of ARR1 (ARR1RD-DBD) as well as the ARR1DBD-DNA complex from Arabidopsis. Analyses of the ARR1DBD-DNA complex have revealed the structural basis for sequence-specific recognition of the GAT trinucleotide by ARR1. In particular, comparing the ARR1RD-DBD and ARR1DBD-DNA structures reveals that unphosphorylated ARR1RD-DBD exists in a closed conformation with extensive contacts between the RD and DBD. In vitro and vivo functional assays have further suggested that phosphorylation of the RD weakens its interaction with DBD, subsequently permits the DNA binding capacity of DBD, and promotes the transcriptional activity of ARR1. Our findings thus provide mechanistic insights into phosphorelay activation of gene transcription in response to cytokinin.


Assuntos
Arabidopsis , Citocininas , Ativação Transcricional , Arabidopsis/genética , Reguladores de Crescimento de Plantas , DNA
2.
Radiat Oncol ; 18(1): 129, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542246

RESUMO

PURPOSE: In this study, we aimed to compare the radiation-induced hepatic toxicity (RIHT) outcomes of radiotherapy (RT) plus antibodies against programmed cell death protein 1 (anti-PD1) versus RT alone in patients with hepatocellular carcinoma (HCC), evaluate prognostic factors of non-classic radiation-induced liver disease (ncRILD), and establish a nomogram for predicting the probability of ncRILD. PATIENTS AND METHODS: Patients with unresectable HCC treated with RT and anti-PD1 (RT + PD1, n = 30) or RT alone (n = 66) were enrolled retrospectively. Patients (n = 30) in each group were placed in a matched cohort using propensity score matching (PSM). Treatment-related hepatotoxicity was evaluated and analyzed before and after PSM. The prognostic factors affecting ncRILD were identified by univariable logistic analysis and Spearman's rank test in the matched cohort to generate a nomogram. RESULTS: There were no differences in RIHT except for increased aspartate aminotransferase (AST) ≥ grade 1 and increased total bilirubin ≥ grade 1 between the two groups before PSM. After PSM, AST ≥ grade 1 occurred more frequently in the RT + PD1 group (p = 0.020), and there were no significant differences in other hepatotoxicity metrics between the two groups. In the matched cohort, V25, tumor number, age, and prothrombin time (PT) were the optimal prognostic factors for ncRILD modeling. A nomogram revealed a good predictive performance (area under the curve = 0.82). CONCLUSIONS: The incidence of RIHT in patients with HCC treated with RT + PD1 was acceptable and similar to that of RT treatment. The nomogram based on V25, tumor number, age, and PT robustly predicted the probability of ncRILD.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Receptor de Morte Celular Programada 1 , Pontuação de Propensão
3.
Nat Plants ; 9(4): 605-615, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36928775

RESUMO

Axial chirality of biaryls can generate varied bioactivities. Gossypol is a binaphthyl compound made by cotton plants. Of its two axially chiral isomers, (-)-gossypol is the bioactive form in mammals and has antispermatogenic activity, and its accumulation in cotton seeds poses health concerns. Here we identified two extracellular dirigent proteins (DIRs) from Gossypium hirsutum, GhDIR5 and GhDIR6, which impart the hemigossypol oxidative coupling into (-)- and (+)-gossypol, respectively. To reduce cotton seed toxicity, we disrupted GhDIR5 by genome editing, which eliminated (-)-gossypol but had no effects on other phytoalexins, including (+)-gossypol, that provide pest resistance. Reciprocal mutagenesis identified three residues responsible for enantioselectivity. The (-)-gossypol-forming DIRs emerged later than their enantiocomplementary counterparts, from tandem gene duplications that occurred shortly after the cotton genus diverged. Our study offers insight into how plants control enantiomeric ratios and how to selectively modify the chemical spectra of cotton plants and thereby improve crop quality.


Assuntos
Gossipol , Animais , Gossipol/toxicidade , Gossipol/análise , Gossipol/química , Edição de Genes , Gossypium/genética , Gossypium/metabolismo , Sementes/metabolismo , Mamíferos/genética
4.
Radiat Oncol ; 18(1): 48, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890592

RESUMO

BACKGROUND: The incidence of classic radiation-induced liver disease (cRILD) has been significantly reduced. However, non-classic radiation-induced liver disease (ncRILD) remains a major concern following radiotherapy in patients with hepatocellular carcinoma (HCC). This study evaluated the incidence of ncRILD following intensity-modulated radiotherapy (IMRT) for Child-Pugh grade B (CP-B) patients with locally advanced HCC and established a nomogram for predicting ncRILD probability. METHODS: Seventy-five CP-B patients with locally advanced HCC treated with IMRT between September 2014 and July 2021 were included. The max tumor size was 8.39 cm ± 5.06, and the median prescribed dose was 53.24 Gy ± 7.26. Treatment-related hepatotoxicity was evaluated within three months of completing IMRT. A nomogram model was formulated to predict the probability of ncRILD, using univariate and multivariate analysis. RESULTS: Among CP-B patients with locally advanced HCC, ncRILD occurred in 17 (22.7%) patients. Two patients (2.7%) exhibited a transaminase elevation of ≥ G3, fourteen (18.7%) exhibited a Child-Pugh score increase of ≥ 2, and one (1.3%) demonstrated both a transaminase elevation of ≥ G3 and a Child-Pugh score increase of ≥ 2. No cRILD cases were observed. A mean dose to the normal liver of ≥ 15.1 Gy was used as the cutoff for ncRILD. Multivariate analysis revealed that the prothrombin time before IMRT, tumour number, and mean dose to the normal liver were independent risk factors for ncRILD. The nomogram established on the basis of these risk factors displayed exceptional predictive performance (AUC = 0.800, 95% CI 0.674-0.926). CONCLUSIONS: The incidence of ncRILD following IMRT for CP-B patients with locally advanced HCC was acceptable. A nomogram based on prothrombin time before IMRT, tumour number, and mean dose to the normal liver accurately predicted the probability of ncRILD in these patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Lesões por Radiação , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/complicações , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/complicações , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Transaminases , Dosagem Radioterapêutica
5.
J Clin Transl Hepatol ; 11(2): 341-349, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-36643048

RESUMO

Background and Aims: The study aimed to create a new staging model for radiotherapy-based treatment for prognostic hepatocellular carcinoma (HCC) classification. Methods: The training cohort comprised 658 patients receiving stereotactic body radiotherapy and external validation cohort comprised 533 patients receiving three-dimensional conformal radiotherapy and intensity-modulated radiotherapy. We established a modified staging system as follows: stage I, solitary nodule without macrovascular invasion, or 2-3 nodules no more than 3.0 cm apart, and performance status (PS) 0-2 (Ia: ALBI-1 grade; Ib: ALBI-2 or 3 grade); stage II: 2-3 nodules with any one nodule more than 3.0-cm apart, or ≥4 nodules, and performance status 0-2 (IIa: ALBI-1 grade; IIb: ALBI-2 grade); stage III: macrovascular invasion, regional lymph node metastasis or distant metastasis, and performance status 0-2 (IIIa: ALBI-1 grade; IIIb: ALBI-2 grade); stage IV: performance status 3-4, or performance status 0-2 with ALBI-3 grade. We analyzed long-term overall survival based on different stages. Results: The staging model showed an excellent ability to discriminate patients according to four stages and seven substages with notably different curves in the training and validation cohort. The median survival decreased from stages I to IV with 63.0 months in stage I (not reached in Ia, and 53.0 months in Ib), 24.0 months in stage II (28.0 months in IIa, and 22.0 months in IIb), 11.0 months in stage III (18.0 months in IIIa, and 9.0 months in IIIb), and less than 9.0 months in stage IV in the training cohort. Conclusions: The modified staging model may provide an alternative for clinical radiation oncologists.

6.
BMC Gastroenterol ; 22(1): 510, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494634

RESUMO

BACKGROUND: For patients with unresectable hepatocellular carcinoma (uHCC), intensity-modulated radiotherapy (IMRT) has become one of the options for clinical local treatment. Immune parameters, including platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR) and systemic immune inflammatory (SII), predict survival in various cancers. This study aimed to determine whether peripheral immune parameters can predict survival in patients with uHCC undergoing IMRT and establish a clinically useful prognostic nomogram for survival prediction. METHODS: The clinical data of 309 HCC patients were retrospectively analyzed and randomly divided into training (n = 216) and validation (n = 93) cohorts. PLR, NLR and SII were collected before and after IMRT. Univariate and multivariate Cox analyses were performed to identify independent prognostic factors affecting survival, which were used to generate a nomogram. RESULTS: The median survival was 16.3 months, and significant increases in PLR, NLR, and SII were observed after IMRT (P < 0.001). High levels of immune parameters were associated with poor prognosis (P < 0.001); enlarged spleen, Barcelona clinic liver cancer stage (B and C), post-SII, and delta-NLR were independent risk factors for survival and were included in the nomogram, which accurately predicted 3- and 5-year survival. The nomogram was well verified in the validation cohort. CONCLUSIONS: High levels of immune parameters are associated with poor prognosis in uHCC patients receiving IMRT. Our nomogram accurately predicts the survival of patients with uHCC receiving IMRT.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Prognóstico , Estudos Retrospectivos , Neoplasias Hepáticas/patologia , Inflamação/patologia , Linfócitos/patologia , Neutrófilos
7.
J Integr Plant Biol ; 64(10): 1935-1951, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35920566

RESUMO

The key enzymes involved in the flavonoid biosynthesis pathway have been extensively studied in seed plants, but relatively less in ferns. In this study, two 4-Coumarate: coenzyme A ligases (Sc4CL1 and Sc4CL2) and one novel chalcone synthase (ScCHS1) were functionally characterized by mining the Stenoloma chusanum transcriptome database. Recombinant Sc4CLs were able to esterify various hydroxycinnamic acids to corresponding acyl-coenzyme A (CoA). ScCHS1 could catalyze p-coumaroyl-CoA, cinnamoyl-CoA, caffeoyl-CoA, and feruloyl-CoA to form naringenin, pinocembrin, eriodictyol, and homoeriodictyol, respectively. Moreover, enzymatic kinetics studies revealed that the optimal substrates of ScCHS1 were feruloyl-CoA and caffeoyl-CoA, rather than p-coumaroyl-CoA, which was substantially different from the common CHSs. Crystallographic and site-directed mutagenesis experiments indicated that the amino acid residues, Leu87, Leu97, Met165, and Ile200, located in the substrate-binding pocket near the B-ring of products, could exert a significant impact on the unique catalytic activity of ScCHS1. Furthermore, overexpression of ScCHS1 in tt4 mutants could partially rescue the mutant phenotypes. Finally, ScCHS1 and Sc4CL1 were used to synthesize flavanones and flavones with multi-substituted hydroxyl and methoxyl B-ring in Escherichia coli, which can effectively eliminate the need for the cytochrome P450 hydroxylation/O-methyltransferase from simple phenylpropanoid acids. In summary, the identification of these important Stenoloma enzymes provides a springboard for the future production of various flavonoids in E. coli.


Assuntos
Gleiquênias , Flavanonas , Flavonas , Sequência de Aminoácidos , Gleiquênias/genética , Ácidos Cumáricos , Escherichia coli/genética , Escherichia coli/metabolismo , Flavanonas/metabolismo , Flavonoides/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Metiltransferases/metabolismo , Aminoácidos
8.
Hepatol Int ; 16(5): 1179-1187, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36001228

RESUMO

PURPOSE: Stereotactic body radiotherapy (SBRT) may have significant immunomodulatory effects that enhance tumor response to immune checkpoint inhibitors. This phase 2 clinical trial was conducted to evaluate the safety and efficacy of combining palliative SBRT with camrelizumab (an anti-PD1 monoclonal antibody) in patients with unresectable hepatocellular carcinoma (uHCC). METHODS: Patients with uHCC, Child-Pugh A/B liver function, and at least one measurable lesion were enrolled between April 2020 and August 2022. Patients were administered 200 mg camrelizumab intravenously from the first day of palliative SBRT and then every 3 weeks. Palliative SBRT was delivered daily over five fractions per week, with a dose range of 30-50 Gy. The primary endpoints were objective response rate (ORR) and safety. This trial was registered at ClinicalTrials.gov (NCT04193696). RESULTS: Twenty-one patients were enrolled; the median radiation dose was 40 Gy, and the median number of cycles of camrelizumab was five. The ORR was 52.4%. After a median follow-up of 19.7 months, the median progression-free and overall survival were 5.8 and 14.2 months, respectively. The overall survival probability was 85.7% at 6 months, 76.2% at 9 months, and 59.9% at 12 months. All grade 3 treatment-related adverse events (TRAEs) occurred in five patients (23.8%) and were manageable. No grade 4/5 TRAEs were observed. CONCLUSION: Palliative SBRT plus camrelizumab showed promising antitumor activity against uHCC. Toxicities were manageable with no unexpected safety issues. This study provides evidence of a new therapeutic method for the treatment of uHCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/radioterapia , Radiocirurgia/métodos
9.
Radiat Oncol ; 17(1): 106, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690773

RESUMO

BACKGROUND: The combination of transcatheter arterial chemoembolization (TACE) plus sorafenib prolonged progression-free survival (PFS) and overall survival (OS) than sorafenib or TACE monotherapy for patients with hepatocellular carcinoma (HCC). This study assessed the efficacy and safety of radiotherapy (RT) plus monoclonal antibody against programmed cell death 1 (anti-PD1) versus TACE plus sorafenib for patients with advanced HCC. METHODS: Patients with advanced HCC who treated with RT plus anti-PD1 and TACE plus sorafenib were enrolled. Objective response rate (ORR), PFS, disease control rate (DCR) and OS were calculated to assess the antitumor response and the treatment-related adverse events to the safety. RESULTS: Between January 2018 to March 2021, 37 patients underwent RT plus anti-PD1 and 41 patients underwent TACE plus sorafenib. The baseline characteristics between the two groups were comparable. The ORR and DCR were significantly higher in the RT + PD1 group than the TACE plus sorafenib group according to RECIST 1.1 (54.05% vs. 12.20%, P < 0.001; 70.27% vs. 46.37%, P = 0.041; respectively) and according to mRECIST (56.76% vs. 31.71%, P = 0.039; 70.27% vs. 46.37%, P = 0.041; respectively). RT plus anti-PD1 provided significantly better PFS (HR, 0.51; 95% CI 0.30-0.86; P = 0.017) than TACE plus sorafenib. Moreover, patients with RT plus anti-PD1 had significantly higher 3-, 6-, and 9-month OS rates than those with TACE plus sorafenib(97.3% vs. 92.30%, P < 0.001; 91.89% vs. 68.60%, P < 0.001; 75.5% vs. 60.60%, P < 0.001; respectively). The median OS was more favorable 17.4 months for the RT + PD1 group and 11.9 months for the TACE plus sorafenib group. No treatment-related death was observed. Grade 3 or more treatment-related adverse events (TRAEs) occurred significantly less in patients in the RT + PD1 group than the TACE plus sorafenib group (29.7% vs. 75.6%, P < 0.001), and all TRAEs were manageable. CONCLUSIONS: In this real-world study, RT plus anti-PD1 showed significantly promising efficacy and manageable safety than TACE plus sorafenib in patients with advanced HCC. Toxicities were manageable, with no unexpected safety signals. The study provides evidence on a new therapeutic method in the treatment of advanced HCC.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/efeitos adversos , Terapia Combinada , Humanos , Neoplasias Hepáticas/patologia , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Sorafenibe/uso terapêutico
10.
Plant Biotechnol J ; 20(1): 129-142, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34490975

RESUMO

The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4'-deoxyflavones, which are reported to have many health-promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4'-deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side-effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O-methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3'-hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7-methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6-hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co-expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4'-deoxyflavone substrates are supplied in the medium. Co-expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.


Assuntos
Plantas Medicinais , Scutellaria baicalensis , Flavonoides/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Raízes de Plantas/metabolismo , Scutellaria baicalensis/química , Scutellaria baicalensis/metabolismo
11.
Plant Physiol ; 188(3): 1496-1506, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34893909

RESUMO

Tanshinone ⅡA (TⅡA), a diterpene quinone with a furan ring, is a bioactive compound found in the medicinal herb redroot sage (Salvia miltiorrhiza Bunge), in which both furan and dihydrofuran analogs are present in abundance. Progress has been made recently in elucidating the tanshinone biosynthetic pathway, including heterocyclization of the dihydrofuran D-ring by cytochrome P450s; however, dehydrogenation of dihydrofuran to furan, a key step of furan ring formation, remains uncharacterized. Here, by differential transcriptome mining, we identified six 2-oxoglutarate-dependent dioxygenase (2-ODD) genes whose expressions corresponded to tanshinone biosynthesis. We showed that Sm2-ODD14 acts as a dehydrogenase catalyzing the furan ring aromatization. In vitro Sm2-ODD14 converted cryptotanshinone to TⅡA and thus was designated TⅡA synthase (SmTⅡAS). Furthermore, SmTⅡAS showed a strict substrate specificity, and repression of SmTⅡAS expression in hairy root by RNAi led to increased accumulation of total dihydrofuran-tanshinones and decreased production of furan-tanshinones. We conclude that SmTⅡAS controls the metabolite flux from dihydrofuran- to furan-tanshinones, which influences medicinal properties of S. miltiorrhiza.


Assuntos
Dioxigenases/genética , Dioxigenases/metabolismo , Diterpenos/metabolismo , Furanos/metabolismo , Plantas Medicinais/metabolismo , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo , Vias Biossintéticas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Raízes de Plantas/metabolismo
12.
Sci Adv ; 7(50): eabl3594, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34878842

RESUMO

Coenzyme Q (CoQ) is an electron transporter in the mitochondrial respiratory chain, yet the biosynthetic pathway in eukaryotes remains only partially resolved. C6-hydroxylation completes the benzoquinone ring full substitution, a hallmark of CoQ. Here, we show that plants use a unique flavin-dependent monooxygenase (CoqF), instead of di-iron enzyme (Coq7) operating in animals and fungi, as a C6-hydroxylase. CoqF evolved early in eukaryotes and became widely distributed in photosynthetic and related organisms ranging from plants, algae, apicomplexans, and euglenids. Independent alternative gene losses in different groups and lateral gene transfer have ramified CoqF across the eukaryotic tree with predominance in green lineages. The exclusive presence of CoqF in Streptophyta hints at an association of the flavoenzyme with photoautotrophy in terrestrial environments. CoqF provides a phylogenetic marker distinguishing eukaryotes and represents a previously unknown target for drug design against parasitic protists.

13.
Front Oncol ; 11: 680303, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513671

RESUMO

BACKGROUND: In this study, we designed a new (Su'S) target area delineation to protect the normal liver during liver regeneration and prospectively evaluate liver regeneration after radiotherapy, as well as to explore the clinical factors of liver regeneration and established a model and nomogram. METHODS: Thirty patients treated with preoperative downstaging radiotherapy were prospectively included in the training cohort, and 21 patients treated with postoperative adjuvant radiotherapy were included in the validation cohort. The cut-off points of each optimal predictor were obtained using receiver-operating characteristic analysis. A model and nomogram for liver regeneration after radiotherapy were developed and validated. RESULTS: After radiotherapy, 12 (40%) and 13 (61.9%) patients in the training and validation cohorts experienced liver regeneration, respectively. The risk stratification model based on the cutoffs of standard residual liver volume spared from at least 20 Gy (SVs20 = 303.4 mL/m2) and alanine aminotransferase (ALT=43 u/L) was able to effectively discriminate the probability of liver regeneration. The model and nomogram of liver regeneration based on SVs20 and ALT showed good prediction performance (AUC=0.759) in the training cohort and performed well (AUC=0.808) in the validation cohort. CONCLUSIONS: SVs20 and ALT were optimal predictors of liver regeneration. This model may be beneficial to the constraints of the normal liver outside the radiotherapy-targeted areas.

14.
Org Biomol Chem ; 19(30): 6650-6656, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34264250

RESUMO

The exquisite chemodiversity of terpenoids is the product of the large diverse terpene synthase (TPS) superfamily. Here, by using structural and phylogenetic analyses and site-directed mutagenesis, we identified a residue (Cys440 in Nicotiana tabacum 5-epi-aristolochene synthase) proximal to an ion-binding motif common to all TPSs and named the preNSE/DTE residue, which determines the product specificity of sesquiterpene synthases from different plant species. In sesquiterpene synthases catalyzing 1,10-cyclization (1,10-cyclases) of farnesyl diphosphate, mutation of the residue in both specific and promiscuous 1,10-cyclases from different lineages leads to the accumulation of monocyclic germacrene A-11-ol, which is "short-circuited" from complex cyclization cascades, suggesting a key role of this residue in generating the first common intermediate of 1,10-cyclization. Altering this residue in a specific 1,11-cyclase results in alternative 1,10-cyclization products. Moreover, the preNSE/DTE residue can be harnessed to engineer highly specific sesquiterpene synthases for an improved proportion of high-value terpenoids, such as patchoulol, a main constituent of several traditional Chinese medicines that could treat SARS-CoV-2.


Assuntos
Alquil e Aril Transferases/química , Alquil e Aril Transferases/metabolismo , Biocatálise , Alquil e Aril Transferases/genética , Domínio Catalítico , Ciclização , Modelos Moleculares , Mutagênese Sítio-Dirigida , Filogenia , Nicotiana/enzimologia
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(9): 1001-1006, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-32933634

RESUMO

OBJECTIVE: To study the clinical screening and genetic diagnosis of children suspected of Prader-Willi syndrome (PWS), as well as the differences in the scores of clinical diagnostic criteria among the children with a confirmed diagnosis of PWS. METHODS: A total of 94 children suspected of PWS who were admitted from July 2016 to December 2018 were enrolled as subjects. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was performed to confirm the diagnosis. For the children with a confirmed diagnosis of PWS, the scores of clinical diagnostic criteria were determined, and the perinatal characteristics were analyzed. RESULTS: A total of 11 children with PWS were confirmed by MS-MLPA, with a detection rate of 12%, among whom there were 7 boys and 4 girls, with a median age of 3 years and 4 months (range 25 days to 6 years and 8 months) at the time of confirmed diagnosis. Among the 11 children with PWS, only 5 children (45%) met the criteria for clinical diagnosis. The main perinatal characteristics of the children with PWS were decreased fetal movement (9 cases, 82%), cesarean section birth (11 cases, 100%), hypotonia (11 cases, 100%), feeding difficulties (11 cases, 100%), and weak crying (11 cases, 100%). CONCLUSIONS: Gene testing should be performed as early as possible for children suspected of PWS by clinical screening. PWS may be missed if only based on the scores of clinical diagnostic criteria.


Assuntos
Síndrome de Prader-Willi , Cesárea , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Metilação , Hipotonia Muscular , Gravidez
16.
Front Oncol ; 10: 1205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850352

RESUMO

Background: Macroscopic vascular invasion (MVI) is a terminal manifestation of hepatocellular carcinoma (HCC) and carries an extremely poor prognosis. In Chinese and Korean HCC guidelines, transarterial chemoembolization (TACE), or/and radiotherapy (RT) is adopted for treatment of MVI. In the current study, we aimed to compare the long-term outcome of TACE + RT to that of RT alone in patients with local advanced HCC with MVI. Methods: In this retrospective study, 148 treatment-naive patients of HCC with MVI were enrolled. Of the patients enrolled, 49 received TACE + RT treatment, whereas 99 patients received RT alone as a monotherapy. Overall survival (OS), progression-free survival (PFS), and intrahepatic control were evaluated using univariable and propensity score-matched analyses. Results: During follow-up, 126 patients (85.1%) died. The median follow-up time was 55.0 months in the RT group and 57.0 months in the TACE + RT group. The TACE + RT group showed better OS and PFS than the RT group, but intrahepatic control was comparable in these two groups. Of 41 cases well-pairs after propensity score matching, the associations between TACE + RT and better OS and PFS remained (15.0 vs. 8.0 months, and 8.0 vs. 4.0 months, all P < 0.05). The 1-, 2-, 3-, and 5-years OS rates in the TACE + RT group were 56.1, 28.6, 20.8, and 15.7 vs. 31.5%, 13.1%, 9.8%, and 6.7% in the RT group, respectively (P = 0.017). The 6-, 12-, and 24-months rates in the TACE + RT group were 51.2, 39.0, and 23.1% vs. 36.6%, 13.9%, and 11.1% in the RT group, respectively (P = 0.04). Two patients (4.1%) experienced radiation-induced liver disease (RILD), and one (2.0%) experienced RT-related gastrointestinal (GI) bleed in the TACE + RT groups. Nine patients (9.1%) experienced RILD, and two (2.0%) experienced RT-related GI bleed in the RT groups. Conclusion: Transarterial chemoembolization + RT had well-complementarity with no more complications than RT alone, providing a better PFS and OS compared with RT-alone treatment for HCC with MVI.

17.
Nat Chem Biol ; 16(3): 250-256, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31932723

RESUMO

In plants, lineage-specific metabolites can be created by activities derived from the catalytic promiscuity of ancestral proteins, although examples of recruiting detoxification systems to biosynthetic pathways are scarce. The ubiquitous glyoxalase (GLX) system scavenges the cytotoxic methylglyoxal, in which GLXI isomerizes the α-hydroxy carbonyl in the methylglyoxal-glutathione adduct for subsequent hydrolysis. We show that GLXIs across kingdoms are more promiscuous than recognized previously and can act as aromatases without cofactors. In cotton, a specialized GLXI variant, SPG, has lost its GSH-binding sites and organelle-targeting signal, and evolved to aromatize cyclic sesquiterpenes bearing α-hydroxyketones to synthesize defense compounds in the cytosol. Notably, SPG is able to transform acetylated deoxynivalenol, the prevalent mycotoxin contaminating cereals and foods. We propose that detoxification enzymes are a valuable source of new catalytic functions and SPG, a standalone enzyme catalyzing complex reactions, has potential for toxin degradation, crop engineering and design of novel aromatics.


Assuntos
Aromatase/metabolismo , Lactoilglutationa Liase/química , Lactoilglutationa Liase/metabolismo , Aromatase/química , Produtos Biológicos , Catálise , Citosol/metabolismo , Glutationa/metabolismo , Gossypium/metabolismo , Complexos Multienzimáticos , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo
19.
Journal of Medical Postgraduates ; (12): 108-112, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-818384

RESUMO

Exosome are nano-scale vesicles with a phospholipid bilayer membrane structure. They are widely distributed in body fluids such as serum, urine, and saliva, containing various biologically active substances such as RNA, DNA fragment and protein. Exosomes contain miRNAs called exosomal-derived miRNAs. Gastrointestinal tumors are one of the common malignant tumors. Effective screening and early diagnosis are clinical priorities and difficulties. Exosome-derived miRNAs in human circulation can be used as potential biomarkers for early diagnosis of digestive tract tumors. This article reviews the concepts and biological characteristics of exosomal-derived miRNAs, the detection of exosome-derived miRNAs and the relationship between exosome-derived miRNAs and digestive tract tumors.

20.
Journal of Medical Postgraduates ; (12): 331-336, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-818237

RESUMO

Circular RNA (circRNA) is a class of endogenous non-coding RNA molecules with a stable closed loop structure formed by reverse splicing. It is more conserved and stable than linear RNA and involves cell development, proliferation, differentiation and apoptosis. Long-term and large-scale studies show the dysregulation of circRNA is associated with the risk of invasion, staging, metastasis, and postoperative recurrence of gastric cancer. This paper reviews the structure, classification, function of circRNA and its clinical significance in gastric cancer.

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