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1.
Zhongguo Gu Shang ; 37(2): 196-206, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38425073

RESUMO

OBJECTIVE: To investigate whether Bushen Huoxue recipe can protect articular cartilage by regulating Akt/mTOR signaling pathway to promote the autophagy of chondrocytes in ovariectomized rats. METHODS: Among 30 SPF 12-week-old female SD rats weighing (247.0±7.0) g, 6 were randomly selected as the blank control group, and the remaining rats were randomly divided into model group, BSHXR-L group, BSHXR-M group and BSHXR-H group, with 6 rats in each group. The protective effect of Bushen Huoxue recipe on articular cartilage injury in rats was determined by visual observation score, muscovine O-solid green staining and immunohistochemistry. The expression of autophagy related proteins was detected by Western-blot, and the relative expression of Akt, mTOR and downstream autophagy genes was detected by qPCR. RESULTS: After modeling, BSHXR (L, M, H) groups could alleviate the histological damage of cartilage. Immunohistochemistry showed that the expression of Collagen-Ⅱand Aggrecan gradually increased, and the expression of MMP-13 gradually decreased, and the differences between BSHXR-M and BSHXR-H groups and model group were statistically significant (P<0.05). The results of Western-blot showed that the autophagy pathway proteins p-Akt/Akt and p-mTOR/mTOR were inhibited in the BSHXR(L, M, H) groups, and the expressions of downstream proteins Beclin-1 and LC3Ⅱwere gradually increased, while p62 was gradually decreased, showing a dose effect. QPCR results showed that BSHXR(L, M, H) groups could promote the relative expression of Beclin-1 and LC3ⅡmRNA, and inhibit the relative expression of p62, Akt, mTOR mRNA, and the differences were statistically significant compared with model group (P<0.05). CONCLUSION: Bushen Huoxue recipe can enhance the cartilage autophagy response by inhibiting the Akt/mTOR signaling pathway, and then protect the cartilage.


Assuntos
Cartilagem Articular , Condrócitos , Medicamentos de Ervas Chinesas , Ratos , Feminino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Proteína Beclina-1/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Autofagia/genética
2.
Zhen Ci Yan Jiu ; 48(10): 993-1000, 2023 Oct 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37879949

RESUMO

OBJECTIVES: To observe the similarities and differences of effects of moxibustion at "Zusanli" (ST36) on target tissues and macrophages polarization in knee osteoarthritis (KOA) and rheumatoid arthritis (RA) rats, and to summarize its efficacy and characteristics. METHODS: Thirty rats were equally and randomly divided into control, KOA, RA, KOA+Moxi and RA+Moxi groups. The KOA model and RA model were induced by injection of sodium monoiodoacetate or Freund's complete adjuvant into the rats' knee joints, respectively. Rats of the KOA+Moxi and RA+Moxi groups received moxibustion stimulation at bilateral ST36 for 30 min, once a day for 21 days, beginning from the 7th day on after modeling. The contents of serum interleukin(IL)-1ß and IL-10 were detected by ELISA. Histopathological changes (Markin score of the knee cartilage and synovial pathology score) of the knee joints were observed after HE staining. The polarization state of M1 and M2 macrophages in the synovial tissue of the knee joints was assessed by detecting the expression of CD86 and CD206 after immunofluorescence staining. RESULTS: Compared with the control group, the content of serum IL-1ß, synovial pathology score, and synovial CD86 expression were significantly increased (P<0.01, P<0.05), while the content of serum IL-10 and synovial CD206 expression markedly decreased (P<0.01) in both KOA and RA groups;the Markin score was increased (P<0.01) in the KOA group. In comparison with the KOA group, the Markin score was obviously decreased (P<0.01), while the content of serum IL-10 and CD206 expression were apparently increased (P<0.01) in the KOA+Moxi group. No significant changes were found in the content of serum IL-1ß, synovial pathology score and CD86 expression in the KOA+Moxi group relevant to the KOA group. In comparison with the RA group, the content of serum IL-1ß, synovial pathology score, and CD86 expression were considerably decreased (P<0.01) in the RA+Moxi group. No marked differences were found in the serum IL-10 level, Markin score, and CD206 expression between RA+Moxi and RA model groups. The increased Markin score was significantly higher in the KOA group than in the RA group (P<0.01), but the increased synovial pathology score was significantly lower in the KOA group than in the RA group (P<0.01). Correspondingly, the effect of moxibustion at ST36 was significantly better in RA model than in KOA model in reducing serum IL-1ß (P<0.05). CONCLUSIONS: Moxibustion at ST36 can effectively reduce cartilage injury of knee joint in rats with KOA and reduce synovial injury in rats with RA, which may be related with its effects in lowering IL-1ß level in RA model by inhibiting the polarization of M1 macrophages, and up-regulating level of IL-10 in KOA model by promoting the polarization of M2 macrophages. However, the relevant mechanism needs to be further studied.


Assuntos
Artrite Reumatoide , Moxibustão , Osteoartrite do Joelho , Ratos , Animais , Interleucina-10/genética , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/terapia , Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Artrite Reumatoide/metabolismo , Articulação do Joelho , Macrófagos/metabolismo
3.
World J Gastrointest Surg ; 15(8): 1673-1683, 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37701703

RESUMO

BACKGROUND: The ratio of lymphocytes to monocytes (LMR) has been shown to be an effective predictor of gastric cancer prognosis. However, its predictive accuracy for signet ring gastric cancer is currently not well understood. AIM: To evaluate the prognosis predictive accuracy of preoperative LMR in signet ring gastric cancer. METHODS: A total of 212 signet ring gastric cancer patients admitted at the Xiangya Hospital of Central South University, Department of Gastrointestinal Surgery, from January 2012 to December 2016 were enrolled in the study. The prognosis predictive accuracy of preoperative LMR was explored based on the area under the receiver operating characteristic. Factors that significantly affect the survival of patients were identified using single factor analysis, and those that were independently associated with signet ring gastric cancer were identified through multivariate analysis. RESULTS: The results of the single factor analysis revealed a strong correlation between the survival of signet ring gastric cancer patients and several factors, including tumor invasion (χ2 = 49.726; P < 0.001), lymph node metastasis (χ2 = 30.269; P < 0.001), pTNM stage (χ2 = 49.322; P < 0.001), surgical approach (χ2 = 8.489; P = 0.004), age (t = -2.213; P < 0.028), carcinoembryonic antigen (CEA) (Z = -3.265; P = 0.001), platelet-to-lymphocyte ratio (Z = -2.196; P = 0.028), LMR (Z = -2.226; P = 0.026), ALB (t = 3.284; P = 0.001), prognostic nutritional index (t = -3.789; P < 0.001) and FIB (Z = -3.065; P = 0.002). Furthermore, the multivariate analysis further demonstrated that age (HR: 0.563, 95%CI: 0.363-0.873), tumor invasion depth (HR: 0.226, 95%CI: 0.098-0.520), pTNM stage (HR: 0.444, 95%CI: 0.255-0.771), preoperative CEA level (HR: 0.597, 95%CI: 0.386-8.790), and preoperative LMR level (HR: 1.776, 95%CI: 1.150-2.741) were independent factors influencing the prognosis of signet ring gastric cancer. CONCLUSION: In signet ring gastric cancer patients, a low preoperative LMR level predicts poor prognosis. The death risk ratio of the low LMR group compared to the high LMR group is 1.776.

4.
Front Neurol ; 14: 1160110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681008

RESUMO

Hereditary spastic paraplegia (HSP) is a group of neurodegenerative diseases with genetic and clinical heterogeneity characterized by spasticity and weakness of the lower limbs. It includes four genetic inheritance forms: autosomal dominant inheritance (AD), autosomal recessive inheritance (AR), X-linked inheritance, and mitochondrial inheritance. To date, more than 82 gene loci have been found to cause HSP, and SPG15 (ZFYVE26) is one of the most common autosomal recessive hereditary spastic paraplegias (ARHSPs) with a thin corpus callosum (TCC), presents with early cognitive impairment and slowly progressive leg weakness. Here, we reported a homozygous pathogenic variant in ZFYVE26. A 19-year-old Chinese girl was admitted to our hospital presenting with a 2-year progressive bilateral leg spasticity and weakness; early cognitive impairment; corpus callosum dysplasia; chronic neurogenic injury of the medulla oblongata supplied muscles; and bilateral upper and lower limbs on electromyogram (EMG). Based on these clinical and electrophysiological features, HSP was suspected. Exome sequencing of the family was performed by high-throughput sequencing, and an analysis of the patient showed a ZFYVE26 NM_015346: c.7111dupA p.(M2371Nfs*51) homozygous mutation. This case reported a new ZFYVE26 pathogenic variant, which was different from the SPG15 gene mutation reported earlier.

5.
Cell Metab ; 35(11): 1915-1930.e8, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37703873

RESUMO

Weight regain after weight loss is a major challenge in the treatment of obesity. Immune cells adapt to fluctuating nutritional stress, but their roles in regulating weight regain remain unclear. Here, we identify a stem cell-like CD7+ monocyte subpopulation accumulating in the bone marrow (BM) of mice and humans that experienced dieting-induced weight loss. Adoptive transfer of CD7+ monocytes suppresses weight regain, whereas inducible depletion of CD7+ monocytes accelerates it. These cells, accumulating metabolic memories via epigenetic adaptations, preferentially migrate to the subcutaneous white adipose tissue (WAT), where they secrete fibrinogen-like protein 2 (FGL2) to activate the protein kinase A (PKA) signaling pathway and facilitate beige fat thermogenesis. Nevertheless, CD7+ monocytes gradually enter a quiescent state after weight loss, accompanied by increased susceptibility to weight regain. Notably, administration of FMS-like tyrosine kinase 3 ligand (FLT3L) remarkably rejuvenates CD7+ monocytes, thus ameliorating rapid weight regain. Together, our findings identify a unique bone marrow-derived metabolic-memory immune cell population that could be targeted to combat obesity.


Assuntos
Medula Óssea , Aumento de Peso , Humanos , Aumento de Peso/fisiologia , Medula Óssea/metabolismo , Obesidade/metabolismo , Redução de Peso , Dieta Redutora , Termogênese/fisiologia , Fibrinogênio
6.
Cell Rep ; 42(3): 112186, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36870057

RESUMO

Branched-chain amino acids (BCAAs) provide nutrient signals for cell survival and growth. How BCAAs affect CD8+ T cell functions remains unexplored. Herein, we report that accumulation of BCAAs in CD8+ T cells due to the impairment of BCAA degradation in 2C-type serine/threonine protein phosphatase (PP2Cm)-deficient mice leads to hyper-activity of CD8+ T cells and enhanced anti-tumor immunity. CD8+ T cells from PP2Cm-/- mice upregulate glucose transporter Glut1 expression in a FoxO1-dependent manner with more glucose uptake, as well as increased glycolysis and oxidative phosphorylation. Moreover, BCAA supplementation recapitulates CD8+ T cell hyper-functions and synergizes with anti-PD-1, in line with a better prognosis in NSCLC patients containing high BCAAs when receiving anti-PD-1 therapy. Our finding thus reveals that accumulation of BCAAs promotes effector function and anti-tumor immunity of CD8+ T cells through reprogramming glucose metabolism, making BCAAs alternative supplementary components to increase the clinical efficacy of anti-PD-1 immunotherapy against tumors.


Assuntos
Aminoácidos de Cadeia Ramificada , Linfócitos T CD8-Positivos , Animais , Camundongos , Aminoácidos de Cadeia Ramificada/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Glucose
7.
World J Gastrointest Surg ; 15(12): 2855-2865, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38222005

RESUMO

BACKGROUND: Gastric cancer (GC) is a deadly tumor with the fifth highest occurrence and highest global mortality rates. Owing to its heterogeneity, the underlying mechanism of GC remains unclear, and chemotherapy offers little benefit to individuals. AIM: To investigate the clinical outcomes of TP53 and CDH1 mutations in GC. METHODS: In this study, 202 gastric adenocarcinoma tumor tissues and their corresponding normal tissues were collected. A total of 490 genes were identified using target capture. Through t-test and Wilcoxon rank-sum test, somatic mutations, microsatellite instability, and clinical statistics, including overall survival, were detected, compared, and calculated. RESULTS: The mutation rates of 32 genes, including TP53, SPEN, FAT1, and CDH1 exceeded 10%. TP53 mutations had a slightly lower overall occurrence rate (33%). The TP53 mutation rate was significantly higher in advanced stages (stage III/IV) than that in early stages (stage I/II) (P < 0.05). In contrast, CDH1 mutations were significantly associated with diffuse GC. TP53 is related to poor prognosis of advanced-stage tumors; nevertheless, CDH1 corresponds to a diffuse type of cancer. TP53 is exclusively mutated in CDH1 and is primarily affected by two distinct GC mechanisms. CONCLUSION: Different somatic mutation patterns in TP53 and CDH1 indicate two major mechanisms of GC.

8.
World J Microbiol Biotechnol ; 39(2): 42, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36513951

RESUMO

Driven by the massive demand in recent years, the production of ß-alanine has significantly progressed in chemical and biological ways. Although the chemical method is relatively mature compared to biological synthesis, its high cost of waste disposal and environmental pollution does not meet the environmental protection standard. Hence, the biological method has become more prevalent as a potential alternative to the chemical synthesis of ß-alanine in recent years. As a result, the aspartate pathway from L-aspartate to ß-alanine (the most significant rate-limiting step in the ß-alanine synthesis) catalyzed by L-aspartate-α-decarboxylase (ADC) has become a research hotspot in recent years. Therefore, it is vital to comprehensively understand the different enzymes that possess a similar catalytic ability to ADC. This review will investigate the exploratory process of unique synthesis features and catalytic properties of ADC/ADC-like enzymes in particular creatures with similar catalytic capacity or high sequence homology. At the same time, we will discuss the different ß-alanine production methods which can apply to future industrialization.


Assuntos
Glutamato Descarboxilase , Isoenzimas , Glutamato Descarboxilase/metabolismo , Ácido Aspártico/metabolismo , beta-Alanina
9.
Front Endocrinol (Lausanne) ; 13: 899731, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060945

RESUMO

Non-alcoholic fatty liver disease (NAFLD), hallmarked by liver steatosis, is becoming a global concern, but effective and safe drugs for NAFLD are still lacking at present. Parathyroid hormone (PTH), the only FDA-approved anabolic treatment for osteoporosis, is important in calcium-phosphate homeostasis. However, little is known about its potential therapeutic effects on other diseases. Here, we report that intermittent administration of PTH ameliorated non-alcoholic liver steatosis in diet-induced obese (DIO) mice and db/db mice, as well as fasting-induced hepatic steatosis. In vitro, PTH inhibits palmitic acid-induced intracellular lipid accumulation in a parathyroid hormone 1 receptor (PTH1R)-dependent manner. Mechanistically, PTH upregulates the expression of genes involved in lipid ß-oxidation and suppresses the expression of genes related to lipid uptake and de novo lipogenesis by activating the cAMP/PKA/CREB pathway. Taken together, our current finding proposes a new therapeutic role of PTH on NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Hormônio Paratireóideo , Animais , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Lipídeos , Lipogênese , Camundongos , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/uso terapêutico , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo
10.
Cell Metab ; 34(8): 1168-1182.e6, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35705079

RESUMO

Exercise can prevent osteoporosis and improve immune function, but the mechanism remains unclear. Here, we show that exercise promotes reticulocalbin-2 secretion from the bone marrow macrophages to initiate bone marrow fat lipolysis. Given the crucial role of lipolysis in exercise-stimulated osteogenesis and lymphopoiesis, these findings suggest that reticulocalbin-2 is a pivotal regulator of a local adipose-osteogenic/immune axis. Mechanistically, reticulocalbin-2 binds to a functional receptor complex, which is composed of neuronilin-2 and integrin beta-1, to activate a cAMP-PKA signaling pathway that mobilizes bone marrow fat via lipolysis to fuel the differentiation and function of mesenchymal and hematopoietic stem cells. Notably, the administration of recombinant reticulocalbin-2 in tail-suspended and old mice remarkably decreases bone marrow fat accumulation and promotes osteogenesis and lymphopoiesis. These findings identify reticulocalbin-2 as a novel mechanosensitive lipolytic factor in maintaining energy homeostasis in bone resident cells, and it provides a promising target for skeletal and immune health.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Animais , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular , Células Cultivadas , Lipólise , Linfopoese , Células-Tronco Mesenquimais/metabolismo , Camundongos
11.
Front Oncol ; 12: 858453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35494021

RESUMO

Molecular subtypes of breast cancer are important references to personalized clinical treatment. For cost and labor savings, only one of the patient's paraffin blocks is usually selected for subsequent immunohistochemistry (IHC) to obtain molecular subtypes. Inevitable block sampling error is risky due to the tumor heterogeneity and could result in a delay in treatment. Molecular subtype prediction from conventional H&E pathological whole slide images (WSI) using the AI method is useful and critical to assist pathologists to pre-screen proper paraffin block for IHC. It is a challenging task since only WSI-level labels of molecular subtypes from IHC can be obtained without detailed local region information. Gigapixel WSIs are divided into a huge amount of patches to be computationally feasible for deep learning, while with coarse slide-level labels, patch-based methods may suffer from abundant noise patches, such as folds, overstained regions, or non-tumor tissues. A weakly supervised learning framework based on discriminative patch selection and multi-instance learning was proposed for breast cancer molecular subtype prediction from H&E WSIs. Firstly, co-teaching strategy using two networks was adopted to learn molecular subtype representations and filter out some noise patches. Then, a balanced sampling strategy was used to handle the imbalance in subtypes in the dataset. In addition, a noise patch filtering algorithm that used local outlier factor based on cluster centers was proposed to further select discriminative patches. Finally, a loss function integrating local patch with global slide constraint information was used to fine-tune MIL framework on obtained discriminative patches and further improve the prediction performance of molecular subtyping. The experimental results confirmed the effectiveness of the proposed AI method and our models outperformed even senior pathologists, which has the potential to assist pathologists to pre-screen paraffin blocks for IHC in clinic.

12.
Cytokine ; 152: 155835, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35240467

RESUMO

OBJECTIVE: To observe the effects of moxibustion on "Shenshu" and "Zusanli" on macrophage polarization and IL-4/STAT6 signaling pathway in rats with rheumatoid arthritis (RA). To further explore the possible anti-inflammatory mechanism of moxibustion in the treatment of RA. METHODS: The rats' right hind paws were injected with freund's complete adjuvant (FCA) to establish the model of RA. Seven days after the injection of FCA, moxibustion therapy was performed on the acupoints of Shenshu (BL23) and Zusanli (ST36) once a day for three weeks. The researchers measured the thickness of the foot pad. ELISA and Histological Analysis were performed to observe the anti-inflammatory effect of moxibustion. Then researchers detected the expression of macrophage phenotype and the expression of IL-4/STAT6 signaling pathway related molecules. RESULTS: It was observed that after the injection of FCA, the rats' feet showed obvious symptoms of redness and swelling. But the symptoms were significantly improved when moxibustion was employed. The study found lower IL-23 and higher IL-4 level in the serum of FCA-injected rats after moxibustion treatment. HE staining showed that the synovium of the RA group was hyperemia and edema, with a large number of inflammatory cells infiltration and vascular dilatation. In the moxibustion group, the degree of synovial hyperemia and edema was improved, and the infiltration of inflammatory cells and vascular dilation were reduced. The study also found that there wer differences among the expressions of macrophage phenotypes in RA, and this was shown by the high expression of CD86 and low expression of CD206. However, the polarization of macrophages in the moxibustion group changed, and that was manifested by enhanced M2-polarized Mφs and inhibited M1-polarized Mφs. Meanwhile, moxibustion suppressed the activation of JAK1, JAK3 and STAT6 in the IL-4/STAT6 signaling pathway, which contributed to the polarization of M2 . CONCLUSION: The results demonstrate that moxibustion not only suppresses the polarization of M1, but also promotes the polarization of M1. The anti-inflammatory effect of moxibustion may be related to the regulation of macrophage polarization through IL-4/STAT6 signaling pathway.


Assuntos
Artrite Reumatoide , Interleucina-4 , Macrófagos , Moxibustão , Fator de Transcrição STAT6 , Animais , Anti-Inflamatórios , Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Polaridade Celular/genética , Polaridade Celular/fisiologia , Hiperemia , Interleucina-4/metabolismo , Macrófagos/metabolismo , Ratos , Fator de Transcrição STAT6/metabolismo
13.
J Oncol ; 2022: 8809469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035484

RESUMO

Recent studies have demonstrated the utility and superiority of DNA repair-related genes as novel biomarkers for cancer diagnosis, prognosis, and therapy. Here, we aimed to screen the potential survival-related DNA repair-related genes in thyroid cancer (TC). TCGA datasets were utilized to analyze the differentially expressed DNA repair-related genes between TC and nontumor tissues. The K-M approach and univariate analysis were employed to screen survival-related genes. RT-PCR was employed to examine the expression of DNA repair-related genes in TC samples and matched noncancer samples. CCK-8 analyses were used to determine cellular proliferation. Herein, our team discovered that the expression of four DNA repair-related genes was remarkably upregulated in TC samples in contrast to noncancer samples. Survival assays identified 14 DNA repair-related genes. In our cohort, we observed that the expression of TAF13 and DCTN4 was distinctly elevated in TC specimens in contrast to nontumor specimens. Moreover, knockdown of TAF13 and DCTN4 was observed to inhibit the TC cellular proliferation. Overall, the upregulation of TAF13 and DCTN4 is related to decreased overall survival in TC patients. Therefore, the assessment of TAF13 and DCTN4 expression may be useful for predicting prognosis in these patients.

14.
J Chem Phys ; 154(5): 054307, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33557555

RESUMO

The activation and hydrogenation of nitrogen are central in industry and in nature. Through a combination of mass spectrometry and quantum chemical calculations, this work reports an interesting result that scandium nitride cations Sc3N+ can activate sequentially H2 and N2, and an amido unit (NH2) is formed based on density functional theory calculations, which is one of the inevitable intermediates in the N2 reduction reactions. If the activation step is reversed, i.e., sequential activation of first N2 and then H2, the reactivity decreases dramatically. An association mechanism, prevalent in some homogeneous catalysis and enzymatic mechanisms, is adopted in these gas-phase H2 and N2 activation reactions mediated by Sc3N+ cations. The mechanistic insights are important to understand the mechanism of the conversion of H2 and N2 to NH3 synthesis under ambient conditions.

15.
Bioprocess Biosyst Eng ; 44(1): 67-79, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32772153

RESUMO

To develop new cellulases for efficient utilization of the lignocellulose, an endoglucanase (CoCel5A) gene from Colletotrichum orchidophilum was synthesized and a recombinant Pichia pastoris GS115/pPIC9K/cocel5A was constructed for secretory expression of CoCel5A. After purification, the protein CoCel5A was biochemically characterized. The endoglucanase CoCel5A exhibited the optimal activity at 55-75 °C and high thermostability (about 85% residual activity) at the temperature of 55 °C after incubation for 3 h. The highest activity of CoCel5A was detected when 100 mM citric acid buffer (pH 4.0-5.0) was used and excellent pH stability (up to 95% residual activity) was observed after incubation in 100 mM citric acid buffer (pH 3.0-6.0) at 4 °C for 24 h. Carboxymethyl cellulose sodium salt (n = approx. 500) (CMC) and ß-D-glucan were the best substrates for CoCel5A among the tested substrates. The kinetic parameters Vmax, Km, and Kcat/Km values against CMC were 290.70 U/mg, 2.65 mg/mL, and 75.67 mL/mg/s, respectively; and 228.31 U/mg, 2.06 mg/mL, and 76.45 mL/mg/s against ß-D-glucan, respectively, suggesting that CoCel5A has high affinity and catalytic efficiency. These properties supported the potential application of CoCel5A in biotechnological and environmental fields.


Assuntos
Celulase/química , Colletotrichum/enzimologia , Proteínas Fúngicas/química , Celulase/genética , Clonagem Molecular , Colletotrichum/genética , Estabilidade Enzimática , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
16.
Phys Chem Chem Phys ; 22(46): 27357-27363, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33231227

RESUMO

The heterogeneous oxidation of isoprene (C5H8) by metal-oxide particles, such as the typical mineral aerosols TiO2, plays an important role in the isoprene atmospheric chemistry. However, the underlying mechanism of C5H8 oxidation remains elusive owing to the complexities of aerosol surfaces and reaction channels. Herein, we report the gas-phase reactions of TixOy+ (x = 1-7, y = 1-14) cations with isoprene by using mass spectrometry and density functional theory (DFT) calculations. Five types of reaction channels were observed: association, hydrogen atom transfer (HAT), C-C bond cleavage, combined oxygen atom transfer (OAT) and HAT and combined OAT and C-C bond cleavage. It is noteworthy that formaldehyde is known as the major oxidation product of isoprene/hydroxyl radicals in the atmosphere. In addition, CO has not been observed in the reactions of isoprene with gas-phase ions. Therefore, the reaction mechanisms of CH2O and CO generation observed in Ti2O5+/C5H8 and Ti4O8+/C5H8 systems were further investigated by DFT calculations, and the calculated results are in agreement with the experimental observations. In these two reactions, both Ti and O atoms can be the adsorption sites for C5H8. The reaction channels and mechanistic information gained in these gas-phase model reactions may offer fundamental insights relevant to the corresponding oxidation processes over titanium oxide aerosols in the atmosphere.

17.
Zhen Ci Yan Jiu ; 45(9): 751-61, 2020 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-32959560

RESUMO

OBJECTIVE: To systematically review the effects of moxibustion on serum cytokines in experimental animals with rheumatoid arthritis. METHODS: PubMed, Embase, Web of Science, The Cochrane Library, CNKI, VIP, Wanfang Data, and CBM were searched for animal experiments on moxibustion intervention for rheumatoid arthritis. Related data were extracted, and RevMan 5.3 was used to perform a meta-analysis of outcome measures, including serum tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), interleukin-17 (IL-17), interleukin-2 (IL-2), interferon-γ (IFN-γ), receptor activator of nuclear factor-kappa B ligand (RANKL), transforming growth factor-ß (TGF-ß), and degree of swelling of diseased joint. RESULTS: A total of 18 studies were included. The detection methods included radioimmunoassay and ELISA and the experimental animal species included rats and rabbits. The studies on serum TNF-α and degree of swelling of diseased joint had publication bias. Meta-analysis showed that the moxibustion group had significant reductions in the serum levels of TNF-α, IL-1, IL-2, IL-6, VEGF, IL-17, and RANKL, significant increases in the serum levels of TGF-ß and IFN-γ, and a significant reduction in the degree of swelling of diseased joints in model animals. CONCLUSION: Moxibustion can effectively regulate levels of the serum cytokines in experimental animals of rheumatoid arthritis and thus reduce inflammatory response and alleviate the swelling of diseased joints.


Assuntos
Artrite Experimental , Artrite Reumatoide , Moxibustão , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Citocinas/genética , Coelhos , Ratos , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio Vascular
18.
Zhongguo Zhen Jiu ; 40(9): 976-82, 2020 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-32959594

RESUMO

OBJECTIVE: To explore the mechanism of moxibustion on the treatment of rheumatoid arthritis (RA) in the perspective of programmed cell death-1 and its ligand 1 (PD-1/PD-L1). METHODS: A total of 30 Japanese big ear white rabbits were randomly divided into a control group, a model group and a moxibustion group, 10 rabbits in each one. In the model group and the moxibustion group, RA model was prepared by the injection of Freund's complete adjuvant (FCA) into the hind knee joint cavities of each rabbit. In the control group, 0.9% sodium chloride solution of the same dose was injected. On the 8th day of experiment, in the moxibustion group, moxibustion was applied to "Shenshu" (BL 23) and "Zusanli" (ST 36), 5 cones at each acupoint, on the bilateral sides alternatively, once a day, 6 treatments as one course, with an interval of 1 days between the treatment courses. Totally, 3 courses of treatment were required. On the 1st, 7th, 14th, 21st and 28th days of experiment, successively, the circumference of the bilateral knee joints was measured with the tape. On the 28th day of experiment, H.E. staining was adopted to observe the histopathological morphology and to evaluate the score of knee synovial tissue. ELISA was used to determined the concentrations of soluble PD-1 (sPD-1) and its ligand 1 (sPD-L1), the interleukin 2 (IL-2) and IL-17 in knee synovial fluid and the concentrations of sPD-1 and sPD-L1 in serum. The histochemistry method was used to determine the expressions of membrane PD-1 (mPD-1) and its ligand 1 (mPD-L1) in spleen tissue. RESULTS: On the 14th, 21st and 28th days of experiment, the circumference of both knee joints was increased in each of the rabbits in the model group as compared with the control group (P<0.01), and it was reduced significantly in the moxibustion group as compared with the model group (P<0.01). Compared with the control group, the hyperplasia of synovial tissue and fibrous tissue, as well as inflammatory cell infiltration were increased obviously in the model group (P<0.01), and they were reduced significantly in the moxibustion group as compared with the model group (P<0.01, P<0.05). Compared with the control group, the concentrations of IL-2 and IL-17 in knee synovial fluid were increased in the rabbits of the model group (P<0.01). Compared with the model group, after the intervention with moxibustion, the concentrations of IL-2 and IL-17 in knee synovial fluid were reduced in the rabbits of the moxibustion group (P<0.05). Compared with the control group, the concentrations of sPD-1 and sPD-L1 in knee synovial fluid and serum in the rabbits of the model group were all increased (P<0.05). Compared with the model group, the concentration of sPD-1 in the knee synovial fluid and serum were reduced in the rabbits of moxibustion group (P<0.05). Compared with the control group, the expressions of mPD-1 and mPD-L1 in spleen tissue were increased obviously in the rabbits of the model group (P<0.05). Compared with the model group, the expression of mPD-L1 in spleen tissue was up-regulated in the rabbits of the moxibustion group (P<0.05). CONCLUSION: Moxibustion could inhibit the over-activation of T cells by enhancing the negative regulation of PD-1/PD-L1 signaling pathway so as to play its effect in treatment of RA.


Assuntos
Artrite Reumatoide , Moxibustão , Receptor de Morte Celular Programada 1 , Animais , Artrite Reumatoide/terapia , Antígeno B7-H1 , Receptor de Morte Celular Programada 1/metabolismo , Coelhos , Distribuição Aleatória , Transdução de Sinais
19.
J Hematol Oncol ; 13(1): 101, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703317

RESUMO

MicroRNAs (miRNAs) play important roles in cell proliferation, differentiation, and survival and may be useful for acute myeloid leukemia (AML) diagnosis and prognosis. In this study, we defined a novel miRNA, hsa-miR-12462, through small RNA sequencing of the bone marrow (BM) cells from 128 AML patients. Overexpression of hsa-miR-12462 in AML cells (U937 and HL-60) significantly decreased their growth rate when compared with those of the wild-type and MOCK controls. In a xenograft mouse model, tumor weight and size in the mice bearing the U937 cells with hsa-miR-12462 overexpression were significantly reduced when compared with those bearing the mock cells. The AML cells overexpressing hsa-miR-12462 had increased sensitivity to cytarabine chemotherapy. Combining the data from the MiRDB, an online microRNA database ( http://mirdb.org ), with the RNA-sequencing results, SLC9A1 was predicted to be one of the targets of hsa-miR-12462. hsa-miR-12462 was further confirmed to bind exclusively to the 3'UTR of SLC9A1 in U937 cells, leading to downregulation of SLC9A1. In summary, a higher level of hsa-miR-12462 in AML cells is associated with increased sensitivity to cytarabine chemotherapy via downregulation of SLC9A1.


Assuntos
Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/fisiologia , RNA Neoplásico/genética , Trocador 1 de Sódio-Hidrogênio/fisiologia , Regiões 3' não Traduzidas , Animais , Citarabina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Camundongos , Proteínas de Neoplasias/genética , Trocador 1 de Sódio-Hidrogênio/genética , Carga Tumoral , Células Tumorais Cultivadas , Células U937 , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Ann Clin Transl Neurol ; 7(2): 200-209, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32023010

RESUMO

OBJECTIVE: To describe the clinical and genetic features of two patients with different phenotypes due to various Dynactin 1 (DCTN1) gene mutations and further explore the phenotype-genotype relationship. METHODS: Patient 1 is a 23-year-old man with congenital foot deformity and life-long distal muscle weakness and atrophy. Patient 2 is a 48-year-old woman with adult-onset progressive weakness, lower limbs atrophy, and pyramid bundle signs. Electrophysiology test showed normal nerve conduction velocity of both patients and neurogenic changes in needle electromyography. Open sural nerve biopsy for Patient 1 showed slight loss of myelinated nerve fibers. Both patients were performed with whole-exome sequencing followed by functional study of identified variants. RESULTS: Two mutations in DCTN1 gene were identified in Patient 1 (c.626dupC) and Patient 2 (c.3823C>T), respectively. In vitro, the wild type mostly located in cytoplasm and colocalized with α-tubulin. However, c.626dupC tended to be trapped into nuclear and the c.3823C>T formed cytoplasmic aggregates, both losing colocalization with α-tubulin. Western blotting showed a truncated mutant with less molecular weight of c.626dupC was expressed. INTERPRETATION: We identify two novel DCTN1 mutations causing different phenotypes: (1) early-onset distal hereditary motor neuropathy plus congenital foot malformation and (2) amyotrophic lateral sclerosis, respectively. We provide the initial evidence that foot developmental deficiency probably arises from subcellular localizing abnormality of Dynactin 1, revealing DCTN1-related spectrum is still expanding.


Assuntos
Complexo Dinactina/genética , Deformidades Congênitas do Pé/genética , Atrofia Muscular Espinal/genética , Adulto , Idade de Início , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
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