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1.
Placenta ; 90: 9-17, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32056557

RESUMO

BACKGROUND: (Macro)autophagy is an important process of self-degradation of macromolecules and organelles that ensures cellular homeostasis and energy preservation during stressful conditions. Dysregulated placental autophagy has been implicated in a wide range of pregnancy complications. Recent studies identified hypoxia as a key regulator of trophoblast autophagy in vitro; however, its effects on placental autophagy in vivo remain incompletely understood. In this study, we evaluated the monochorionic twin anemia-polycythemia sequence (TAPS) placenta as model of discordant placental oxygenation to determine the effects of hypoxia on placental autophagy in utero. METHODS: We performed a retrospective comparative analysis of tissue oxygenation and autophagy in anemic and polycythemic territories of TAPS placentas (N = 12). Archival tissues were subjected to immunohistochemical, immunofluorescence and Western blot analyses of carbonic anhydrase (CA) IX (hypoxia marker) and key autophagy/lysosomal markers. RESULTS: CAIX protein levels were significantly higher in anemic twin territories than in corresponding polycythemic territories, consistent with relative tissue hypoxia. Anemic placental shares further displayed significantly higher levels of LC3I/II (autophagosome markers) and LAMP1/2 (lysosome markers), associated with upregulated expression of lysosome/autophagosome activity-associated markers, transcription factor EB and cathepsin D. The accumulation of autophagosomes and lysosomes in anemic shares was accompanied by elevated p62 protein expression, suggestive of inhibition of the downstream autophagy pathway. CONCLUSIONS: TAPS placentas display striking intertwin discordance in tissue oxygenation and autophagic activity and may provide a suitable model for study of the interrelationship between hypoxia, autophagy, and pregnancy outcome in a monochorionic twin setting.

2.
Plant Biotechnol J ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32058661

RESUMO

Genetically modified crops expressing insecticidal Cry proteins from Bacillus thuringiensis (Bt) have been grown commercially since 1996 and have successfully controlled target pests, reduced insecticide usage and increased yields. A major concern is that Bt crops may trigger outbreaks of non-target herbivores against which they are not effective, by reducing bio-control services provided by natural enemies, as seen with broad-spectrum insecticides.

3.
Int Immunopharmacol ; 81: 106261, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32058928

RESUMO

Exacerbation of chronic obstructive pulmonary disease (COPD) is characterized by acute airway inflammation and mucus hypersecretion, which is by far the most costly aspect of its management. Thus, it is essential to develop therapeutics with low side effects for CODP exacerbation. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA isolated as the major active component of Chinese herbal medicine Danshen. Although it possesses anti-inflammatory, anti-oxidative and anti-apoptotic properties, it remains unknown whether STS protects against COPD exacerbation. In this study, we challenged cigarette smoke (CS)-exposed mice with lipopolysaccharide (LPS), and then treated these mice with STS. We found that STS significantly ameliorated pulmonary inflammatory responses, mucus hypersecretion and lung function decline in CS-exposed mice challenged with LPS. STS treatment also significantly attenuated increased IL-6 and IL-8 releases from cigarette smoke extract (CSE)-treated human bronchial epithelial cells (16HBE) challenged with LPS. Mechanistically, STS reduced activation of ERK1/2 and NF-κB in lungs of CS-exposed mice and CSE-treated 16HBE cells challenged with LPS. Taken together, STS protects against acute exacerbation of CS-induced lung injury, which provides a promising and potential therapeutic avenue to halt acute exacerbation of COPD.

4.
Redox Biol ; 28: 101356, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31704583

RESUMO

Airway remodeling is one of the characteristics for chronic obstructive pulmonary disease (COPD). The mechanism underlying airway remodeling is associated with epithelial-mesenchymal transition (EMT) in the small airways of smokers and patients with COPD. Sirtuin 1 (SIRT1) is able to reduce oxidative stress, and to modulate EMT. Here, we investigated the effects and mechanisms of hydrogen sulfide (H2S) on pulmonary EMT in vitro and in vivo. We found that H2S donor NaHS inhibited cigarette smoke (CS)-induced airway remodeling, EMT and collagen deposition in mouse lungs. In human bronchial epithelial 16HBE cells, NaHS treatment also reduced CS extract (CSE)-induced EMT, collagen deposition and oxidative stress. Mechanistically, NaHS upregulated SIRT1 expression, but inhibited activation of TGF-ß1/Smad3 signaling in vivo and in vitro. SIRT1 inhibition by a specific inhibitor EX527 significantly attenuated or abolished the ability of NaHS to reverse the CSE-induced oxidative stress. SIRT1 inhibition also abolished the protection of NaHS against CSE-induced EMT. Moreover, SIRT1 activation attenuated CSE-induced EMT by modifying TGF-ß1-mediated Smad3 transactivation. In conclusion, H2S prevented CS-induced airway remodeling in mice by reversing oxidative stress and EMT, which was partially ameliorated by SIRT1 activation. These findings suggest that H2S may have therapeutic potential for the prevention and treatment of COPD.

5.
Int J Biol Macromol ; 145: 53-63, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31874273

RESUMO

Protein phosphorylation is a major switch mechanism for cell signaling process regulation within eukaryotic cells. Abnormal phosphorylation is either a cause or consequence of human diseases. It is imperative to comprehensively delve into the relationship between phosphorylation events and cell signaling transduction. NMR spectroscopy, a potent tool for monitoring protein phosphorylation events, is applicable for identifying the phospho-sites, quantifying the kinetic rate, discovering kinase/phosphatase inhibitors and delineating phosphorylation crosstalk with other post-translational modifications. Here, we decipher the recent progress in the investigation of eukaryotic protein O-phosphorylation by NMR spectroscopy. We focus specifically on the dynamic establishment of O-phosphorylation and its role in the cell signaling processes. Simultaneously, we positively propose a strategy for the investigation of acid-labile and "high-energy" N-phosphorylation by NMR spectroscopy. We expect that the strategy could enrich the investigation of protein N-phosphorylation.

6.
Therap Adv Gastroenterol ; 12: 1756284819892477, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31832099

RESUMO

Background: After achieving a clinical complete response through neoadjuvant chemoradiotherapy, a nonoperative management approach for rectal cancer patients known as Wait and Watch (W&W) has gained increasing attention. However, the W&W strategy has been related to higher local recurrence and ambiguous long-term survival. This meta-analysis compared key prognosis indicators between W&W and surgical treatment in an effort to clarify some long-standing points of confusion. Methods: Pubmed, Web of Science, EMbase, Cochrane Library were searched for relevant researches comparing W&W with surgery treatment, with a time criteria set from 1 January 2002 to 4 July 2019. Endpoints were 2-year local regrowth/recurrence, 2-year distant metastasis (plus local regrowth/recurrence), 3- and 5-year disease-free survival (DFS), and overall survival (OS). Results: In total, nine studies with 801 patients were enrolled, of which 348 were managed by W&W and 453 by surgery. Surgery patients were further divided into a pathological complete response (pCR) group (all included patients achieved pCR) and a surgery group (consisting of both pCR and non-pCR patients without deliberate screening). Compared with the surgery group, W&W patients have higher 3- and 5-year OS, and are not inferior on 2-year local regrowth (LR), 2-year distant metastasis (DM)/DM+LR, and 3- and 5-year DFS. On the other hand, compared with the pCR group, the W&W group is inferior on 2-year LR, 3- and 5-year DFS, and 5-year OS, and not inferior on 2-year DM/DM+LR and 3-year OS. Conclusions: In contrast with patients undergoing surgical treatment, the W&W group has higher 3- and 5-year OS, and is not inferior on other major prognostic indicators, which, however, is based on the fact that the tumor stage in the W&W group is generally earlier. Versus surgically treated patients who acquired pCR, W&W group is inferior on all major prognostic indicators except 2-year DM/DM+LR and 3-year OS. Additionally, by comparison of cCR definitions across different studies, we conclude that implementation of the strictest cCR criteria is critical for W&W patients to acquire maximum prognostic benefit.

7.
Onco Targets Ther ; 12: 9873-9885, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819485

RESUMO

Background: Previous studies have shown that P73 antisense RNA 1T (non-protein coding), also known as TP73-AS1, is a long non-coding RNA (lncRNA) and involved in the development of medulloblastoma. However, the regulatory mechanism of lncRNA TP73-AS1 in medulloblastoma was still unclear, the present study was aimed to investigate the detailed functions and the mechanism of TP73-AS1 in regulation of medulloblastoma. Materials and methods: The levels of TP73-AS1, miR-494-3p, and Eukaryotic initiation factor 5A2 (EIF5A2) were determined using quantitative real-time PCR (qRT-PCR), in situ hybridization (ISH), or Immunohistochemistry (IHC). The function of TP73-AS1 in proliferation, apoptosis, migration, and invasion of medulloblastoma cells was evaluated using cell counting Kit-8 (CCK-8), flow cytometry, and transwell assay, respectively. The protein levels were determined by Western blot. Bioinformatics analysis and dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assay were used to search and confirm the target gene of TP73-AS1 and miR-494-3p. The effect of TP73-AS1 knockdown in vivo was detected by animal experiment. Results: The levels of TP73-AS1 and EIF5A2 were up-regulated, while miR-494-3p expression was down-regulated in medulloblastoma tissues and cells, ELF5A2 was a direct target of miR-494-3p, and miR-494-3p bound to TP73-AS1. The knockdown of TP73-AS1 inhibited cell proliferation, invasion, migration, and promoted apoptosis of medulloblastoma cells, while the miR-494-3p inhibitor abolished the effects of TP73-AS1 knockdown on medulloblastoma cells. Conclusion: TP73-AS1 positively regulated EIF5A2 expression by sponging miR-494-3p. These findings suggested that TP73-AS1 served as an oncogene and promoted the progression of medulloblastoma.

8.
Aging (Albany NY) ; 11(24): 11844-11864, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31881011

RESUMO

Hydrogen sulfide (H2S), an endogenous gaseous signal molecule, regulates many pathologies related to aging. Sirtuin 1 (SIRT1) has been shown to protect against mitochondrial dysfunction and other pathological processes, including premature senescence. This study was aimed to investigate whether and how H2S attenuates senescence and apoptosis of alveolar epithelial cells via a SIRT1-dependent mechanism. Our results showed that treatment with sodium hydrosulfide (NaHS), a donor of H2S, attenuated cigarette smoke extract (CSE)-induced oxidative stress, mitochondrial dysfunction, cellular senescence and apoptosis in A549 cells. This was associated with SIRT1 upregulation. SIRT1 activation by a pharmacological activator, SRT1720, attenuated CSE-induced oxidative stress and mitochondrial dysfunction in A549 cells. While SIRT1 inhibition by EX 527 or silencing by siRNA transfection significantly attenuated or abolished the ability of NaHS to reverse the CSE-induced oxidative stress, mitochondrial dysfunction and the imbalance of mitochondrial fusion and fission. Also, SIRT1 inhibition or silencing abolished the protection of NaHS against CSE-induced cellular senescence and apoptosis. In conclusion, H2S attenuates CSE-induced cellular senescence and apoptosis by improving mitochondrial function and reducing oxidative stress in alveolar epithelial cells in a SIRT1-dependent manner. These findings provide novel mechanisms underlying the protection of H2S against cigarette smoke-induced COPD.

9.
Int Immunopharmacol ; : 105979, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31771816

RESUMO

Chronic obstructive pulmonary fibrosis (COPD) is a chronic and fatal lung disease with few treatment options. Sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), was found to alleviate cigarette smoke (CS)-induced emphysema in mice, however, the underlying mechanisms have not yet been clarified. In this study, we investigated its effects on COPD in a CS-induced mouse model in vivo and in cigarette smoke extract (CSE)-stimulated alveolar epithelial A549 cells in vitro. The results showed that NaHS not only relieved emphysema, but also improved pulmonary function in CS-exposed mice. NaHS significantly increased the expressions of tight junction proteins (i.e., ZO-1, Occludin and claudin-1), and reduced apoptosis and secretion of pro-inflammatory cytokines (i.e., TNF-α, IL-6 and IL-1ß) in CS-exposed mouse lungs and CSE-incubated A549 cells, indicating H2S inhibits CS-induced inflammation, injury and apoptosis in alveolar epithelial cells. NaHS also upregulated prolyl hydroxylase (PHD)2, and suppressed hypoxia-inducible factor (HIF)-1α expression in vivo and in vitro, suggesting H2S inhibits CS-induced activation of PHD2/HIF-1α axis. Moreover, NaHS inhibited CS-induced phosphorylation of ERK, JNK and p38 MAPK in vivo and in vitro, and treatment with their inhibitors reversed CSE-induced ZO-1 expression and inflammation in A549 cells. These results suggest that NaHS may prevent emphysema via the suppression of PHD2/HIF-1α/MAPK signaling pathway, and subsequently inhibition of inflammation, epithelial cell injury and apoptosis, and may be a novel strategy for the treatment of COPD.

10.
Acta Biochim Biophys Sin (Shanghai) ; 51(12): 1223-1232, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31735962

RESUMO

The pathogenesis of fatal neurodegenerative prion diseases is closely associated with the conversion of α-helix-rich cellular prion protein into ß-sheet-rich scrapie form. Pathogenic point mutations of prion proteins usually promote the conformational conversion and trigger inherited prion diseases. The G131V mutation of human prion protein (HuPrP) was identified to be involved in Gerstmann-Sträussler-Scheinker syndrome. Few studies have been carried out to address the pathogenesis of the G131V mutant. Here, we addressed the effects of the G131V mutation on oligomerization and fibrillization of the full-length HuPrP(23-231) and truncated HuPrP(91-231) proteins. The G131V mutation promotes the oligomerization but alleviates the fibrillization of HuPrP, implying that the oligomerization might play a crucial role in the pathogenic mechanisms of the G131V mutant. Moreover, the flexible N-terminal fragment in either the wild-type or the G131V mutant HuPrP increases the oligomerization tendencies but decreases the fibrillization tendencies. Furthermore, this mutation significantly alters the tertiary structure of human PrPC and might distinctly change the conformational conversion tendency. Interestingly, both guanidine hydrochloride denaturation and thermal denaturation experiments showed that the G131V mutation does not significantly change the thermodynamic stabilities of the HuPrP proteins. This work may be of benefit to a mechanistic understanding of the conformational conversion of prion proteins and also provide clues for the prevention and treatment of prion diseases.

11.
Surg Endosc ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741161

RESUMO

BACKGROUND: As a key landmark during laparoscopic right colectomy, the classification and variation of the gastrocolic trunk of Henle (GTH) remains to be clarified. The aim of this nationwide multicenter study was to describe the characteristics of the GTH intra-operatively during laparoscopic right colectomies. METHODS: Three hundred seventy-one patients who underwent laparoscopic right colectomies from January 2018 to March 2019 in 25 hospitals across China were enrolled in the study. The length of the GTH, the classification with a precise description of confluent tributaries, and other variations were analyzed. RESULTS: Of the 371 patients, 363 had a GTH. The proportion of type-0, type-I, type-II, and type-III was 15.2% (n = 55), 54.8% (n = 199), 25.3% (n = 92), and 4.7% (n = 17), respectively. The average length of the GTH was 8.5 mm, ranging from 2 to 30 mm. CONCLUSIONS: This is the first multicenter study with a large sample by which the GTH was classified based on laparoscopic intraoperative observation. Variations in the GTH were classified into four types based on the number of colic drainage veins (right colic, superior right colic, middle colic, accessory middle colic, and ileocolic veins), among which the right colic vein was the most common. The length of the GTH was relatively short, and thus might carry a risk of bleeding. Further clinical data should be correlated with the characteristics of the GTH.

12.
Int J Oncol ; 55(6): 1385-1395, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31638200

RESUMO

Eukaryotic initiation factor 3c (eIF3C) is involved in the initiation of protein translation. Aberrant eIF3C expression has been reported in different types of human cancer. The present study aimed to assess the role of eIF3C in the malignant behavior of renal cell carcinoma in vitro and in vivo. eIF3C expression was assessed in 16 pairs of renal cell carcinoma (RCC) and matched distant normal tissues, and in RCC cell lines using immunohistochemistry. Subsequently, eIF3C was depleted using lentiviral short hairpin RNA and cell proliferation, cell cycle distribution and apoptosis of these eIF3C­depleted cells were examined. Additionally, tumor cell xenograft assays in nude mice, Affymetrix microarrays and ingenuity pathway analyses were performed. eIF3C expression was upregulated in RCC tissues and cell lines. Depletion of eIF3C reduced tumor cell proliferation and arrested them at the G1 stage, thus promoting their apoptosis in vitro. Depletion of eIF3C also inhibited the formation and growth of tumor cell xenografts in nude mice. In addition, depletion of eIF3C altered the expression levels of 994 differentially expressed genes in RCC cells (516 genes were upregulated and 478 genes were downregulated). The expression levels of phosphorylated­AKT, c­JUN and NFKB inhibitor α were lower in the shorth hairpin RNA eIF3C­transfected RCC cells compared with in the control group. In conclusion, the present study demonstrated that upregulated eIF3C expression contributed to the development and progression of RCC. Future studies should further evaluate whether eIF3C could be used as a potential strategy for RCC targeting therapy.

13.
Acta Biochim Biophys Sin (Shanghai) ; 51(11): 1158-1167, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31650179

RESUMO

Intracellular proteolysis is attracting more and more attention for its unique and important character in Mycobacterium tuberculosis (Mt). The ClpS protein from Mt (MtClpS) plays a critical role in intracellular proteolysis by recognizing N-end rule substrates, which makes it become a potential target for antibacterial drugs. However, the molecular mechanism of MtClpS recognizing N-end rule substrates remains unclear. Preparation of highly concentrated and pure MtClpS protein is a prerequisite for further structural and functional studies. In the present work, we tried several fusion tags and various expression conditions to maximize the production of MtClpS in Escherichia coli. We established an efficient approach for preparing the MtClpS protein with a high yield of 24.7 mg/l and a high purity of 98%. After buffer screening, we obtained a stable MtClpS protein sample concentrated at 0.63 mM in the presence of glycerol, l-Arginine, and l-Glutamate. Moreover, circular dichroism characterization indicated that the secondary structure of MtClpS consists of 38% α-helix and 24% ß-sheet. The 2D 1H-15N HSQC nuclear magnetic resonance spectrum showed a good dispersion of resonance peaks with uniform intensity, indicating that the purified MtClpS protein was well folded and conformationally homogeneous. Isothermal titration calorimetry experiments revealed significant interactions of MtClpS with N-end rule peptides beginning with Leu, Tyr, Trp, or Phe. Furthermore, residues D34, D35, and H66 were confirmed as key residues for MtClpS recognizing the N-end rule peptide. The successful expression and biophysical characterization of MtClpS enabled us to gain insight into the molecular mechanism of MtClpS recognizing N-end rule substrates. The obtained stable and pure recombinant MtClpS will enable future inhibitor screening experiments.

14.
Front Pharmacol ; 10: 941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31555131

RESUMO

Endothelial cell (EC) apoptosis contributes to cigarette smoke (CS)-induced pulmonary emphysema. Metabolism of glucose, glutamine, and fatty acid is dysregulated in patients with chronic obstructive pulmonary disease (COPD). Whether CS causes metabolic dysregulation in ECs leading to development of COPD remains elusive. We hypothesized that CS alters metabolism, resulting in apoptosis in lung ECs. To test this hypothesis, we treated primary mouse pulmonary microvascular ECs (PMVECs) with CS extract (CSE) and employed PMVECs from healthy subjects and COPD patients. We found that mitochondrial respiration was reduced in CSE-treated PMVECs and in PMVECs from COPD patients. Specifically, oxidation of fatty acids (FAO) was reduced in these cells, which linked to reduced carnitine palmitoyltransferase 1a (Cpt1a), an essential enzyme for carnitine shuttle. CSE-induced apoptosis was further increased when cells were treated with a specific Cpt1 inhibitor etomoxir or transfected with Cpt1a siRNA. L-Carnitine treatment augmented FAO but attenuated CSE-induced apoptosis by upregulating Cpt1a. CSE treatment increased palmitate-derived ceramide synthesis, which was reduced by L-carnitine. Although CSE treatment increased glycolysis, inhibiting glycolysis with 2-deoxy-d-glucose had no effects on CSE-mediated apoptosis in lung ECs. Conclusively, FAO reduction increases ceramide and apoptosis in lung ECs treated with CSE, which may contribute to the pathogenesis of COPD/emphysema.

15.
J Cancer ; 10(19): 4552-4563, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528219

RESUMO

Background: It is urgent to develop robust prognostic biomarkers for non-metastatic colorectal cancer (CRC) patients undergoing surgery. The current study aimed to explore and compare the clinical significance of preoperative and postoperative blood tumor biomarkers including circulating tumor cells (CTCs), and develop prognostic models based on tumor biomarkers in patients with stage II-III CRC receiving surgery. Methods: A prospective study was performed to enroll 130 patients with stage II-III CRC receiving surgery between January 2015 and December 2017. Preoperative and postoperative blood tumor biomarkers including CTCs were detected and their prognostic value in predicting tumor recurrence-free survival (RFS) in stage II-III CRC were identified by Kaplan-Meier curves and Cox proportional hazard regression models. Results: CTCs counts within three postoperative days were significantly higher than preoperative CTCs (pre-CTCs). No significant association of pre-CTCs with clinical characteristics and tumor biomarkers was observed while positive postoperative CTCs (post-CTCs) were associated with female, older onset age, high TNM stage, tumor recurrence, and preoperative CEA. Kaplan-Meier curve with log-rank test and univariate Cox proportional hazard regression analysis suggested high N stage, TNM stage, positive pre-carbohydrate antigen (CA) 125, pre-CA19-9, post-CA125, post-CA19-9, post-CA72-4, post-carcinoembryonic antigen (CEA), and post-CTCs were correlated with poor RFS. In multivariate analysis, only TNM stage (adjusted HR=3.786, 95% CI=1.330-10.780; P=0.013), post-CA72-4 (adjusted HR=5.675, 95% CI=2.064-15.604; P=0.001), and post-CTCs (adjusted HR=2.739, 95% CI=1.042-7.200; P=0.041) were significantly correlated with poor RFS. We then developed prognostic models combining post-CTCs and post-CA72-4 with TNM stage or not to stratify the patients into different risk groups. These prognostic models exert a similar good performance in predicting tumor RFS in stage II-III CRC patients. Conclusions: Postoperative CTCs were prior to preoperative CTCs in predicting tumor recurrence survival in non-metastatic CRC patients undergoing surgery. We also developed CTCs-based prognostic models to predict tumor recurrence in stage II-III CRC, which might be used to identify the patients with high risk of recurrence and guide aggressive treatment to improve the clinical outcomes of those patients.

16.
Acta Biochim Biophys Sin (Shanghai) ; 51(9): 960-968, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31389995

RESUMO

Nα-acetylation is a universal protein modification related to a wide range of physiological processes in eukaryotes and prokaryotes. RimI, an Nα-acetyltransferase in Mycobacterium tuberculosis, is responsible for the acetylation of the α-amino group of the N-terminal residue in the ribosomal protein S18. Despite growing evidence that protein acetylation may be correlated with the pathogenesis of tuberculosis, no structural information is yet available for mechanistically understanding the MtRimI acetylation. To enable structural studies for MtRimI, we constructed a serial of recombinant MtRimI proteins and assessed their biochemical properties. We then chose an optimal construct MtRimIC21A4-153 and expressed and purified the truncated high-quality protein for further biophysical and functional characterizations. The 2D 1H-15N heteronuclear single quantum coherence spectrum of MtRimIC21A4-153 exhibits wider chemical shift dispersion and favorable peak isolation, indicating that MtRimIC21A4-153 is amendable for further structural determination. Moreover, bio-layer interferometry experiments showed that MtRimIC21A4-153 possessed similar micromolar affinity to full-length MtRimI for binding the hexapeptide substrate Ala-Arg-Tyr-Phe-Arg-Arg. Enzyme kinetic assays also exhibited that MtRimIC21A4-153 had almost identical enzymatic activity to MtRimI, indicating insignificant influence of the recombinant variations on enzymatic functions. Furthermore, binding sites of the peptide were predicted by molecular docking approach, suggesting that this substrate binds to MtRimI primarily through electrostatic and hydrogen bonding interactions. Our results lay a foundation for the further structural determination and dynamics detection of MtRimI.

17.
Medicine (Baltimore) ; 98(29): e16365, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335682

RESUMO

RATIONALE: Complete small intestinal volvulus is a rare entity in adults, unlike partial intestinal volvulus. Although prompt surgical intervention is the mainstay of treatment, attention should also be paid to recovery of intestinal function postoperatively. Ignoring this issue during the postoperative recovery process can have serious consequences. We report the case of an 82-year-old woman with complete small intestinal volvulus at the root of the superior mesenteric vessel. PATIENTS CONCERNS: The patient was admitted for acute onset (22 hours) of abdominal pain and distention. Nausea and vomiting also developed during this period. DIAGNOSES: Abdominal physical examination was suspicious for peritoneal irritation. Computed tomography scan showed anticlockwise swirl of the mesenteric vessels at the lower margin of the pancreas with distension of the entire small intestine. A complete small intestinal volvulus was diagnosed. INTERVENTIONS: Laparotomy and detorsion of the volvulus were performed after early diagnosis. OUTCOMES: The patient developed intestinal wall edema because of ischemic-reperfusion damage. She exhibited severe abdominal distention and absent intestinal motility. Two days later, she went into septic shock; she died 19 days after surgical intervention. LESSONS: Because complete small intestinal volvulus involves the entire intestine, ischemic-reperfusion intestinal damage after detorsion may be severe and can predict prognosis.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Motilidade Gastrointestinal , Volvo Intestinal/cirurgia , Complicações Pós-Operatórias , Choque Séptico , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Evolução Fatal , Feminino , Humanos , Volvo Intestinal/diagnóstico , Volvo Intestinal/fisiopatologia , Intestino Delgado/fisiopatologia , Intestino Delgado/cirurgia , Laparotomia/efeitos adversos , Laparotomia/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Choque Séptico/diagnóstico , Choque Séptico/etiologia
18.
Toxicol Lett ; 314: 89-97, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325635

RESUMO

Ethanol is a key factor in the pathogenesis of alcoholic liver disease (ALD), commonly characterized as liver inflammation. Recently, circular (circ)RNAs have emerged as important targets to cure liver diseases. However, there are no studies investigating the role of circ_1639 in reducing inflammatory responses in ALD. In this study, we found that circ_1639 was upregulated in Kupffer cells from the livers of alcohol fed mice. We hypothesized that circ_1639 inhibition is a potential novel therapy for treating ALD. To test this hypothesis, RAW 264.7 cells were treated with ethanol and transfected with circ_1639 overexpression or knockdown plasmids. We present western blotting, qRT-PCR, and ELISA data that suggest that circ_1639 is a proinflammatory factor in the liver and is involved in the activation of the NF-κB signaling pathway. Using luciferase reporter assay, we confirmed that microRNA (miR)-122 is a target gene of circ_1639. We also show that TNFRSF13C is a key regulator of RAW 264.7 cell activation, and acts as a downstream target for miR-122. In summary, our results suggest that inhibition of circ_1639 expression may reduce inflammatory responses in ALD.


Assuntos
Mediadores da Inflamação/metabolismo , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , MicroRNAs/metabolismo , RNA/metabolismo , Animais , Receptor do Fator Ativador de Células B/genética , Receptor do Fator Ativador de Células B/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Macrófagos do Fígado/metabolismo , Fígado/patologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/patologia , Hepatopatias Alcoólicas/prevenção & controle , Ativação de Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Células RAW 264.7 , RNA/genética , Transdução de Sinais
19.
Protein Sci ; 28(9): 1720-1726, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31306520

RESUMO

Lon protease is evolutionarily conserved in prokaryotes and eukaryotic organelles. The primary function of Lon is to selectively degrade abnormal and certain regulatory proteins to maintain the homeostasis in vivo. Lon mainly consists of three functional domains and the N-terminal domain is required for the substrate selection and recognition. However, the precise contribution of the N-terminal domain remains elusive. Here, we determined the crystal structure of the N-terminal 192-residue construct of Lon protease from Mycobacterium avium complex at 2.4 å resolution,and measured NMR-relaxation parameters of backbones. This structure consists of two subdomains, the ß-strand rich N-terminal subdomain and the five-helix bundle of C-terminal subdomain, connected by a flexible linker,and is similar to the overall structure of the N domain of Escherichia coli Lon even though their sequence identity is only 26%. The obtained NMR-relaxation parameters reveal two stabilized loops involved in the structural packing of the compact N domain and a turn structure formation. The performed homology comparison suggests that structural and sequence variations in the N domain may be closely related to the substrate selectivity of Lon variants. Our results provide the structure and dynamics characterization of a new Lon N domain, and will help to define the precise contribution of the Lon N-terminal domain to the substrate recognition.

20.
Chin J Cancer Res ; 31(3): 489-498, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31354218

RESUMO

Objective: Our goal is to analyze the trend of colorectal cancer (CRC) regarding the death, incidence and prevalence rates over time, and to provide epidemiological knowledge basis for health policy revision by comparing data about fatal outcomes of CRC in 2017 to those data in 1990, which was extracted from the Global Burden of Disease (GBD). Methods: The time trend and changes of CRC burden from 1990 to 2017 were measured by using the methods and results from the Institute for Health Metrics and Evaluation (IHME) GBD 2017, based on the rates of death, incidence and prevalence. Results: The death rate of CRC is 13.24/100,000, accounting for 1.79% of total deaths in China in 2017. In 1990, CRC ranked 21st in all causes of death in China compared to its 11th ranking in 2017. The death, incidence and prevalence rate of CRC were standardized by the age scale of the global population in 2010, the change of standardized death rate of CRC was not significant, from 9.33/100,000 in 1990 to 10.10/100,000 in 2017. The standardized incidence rate of CRC significantly increased from 12.18/100,000 in 1990 to 22.42/100,000 in 2017. The standardized prevalence rate of CRC significantly increased from 44.55/100,000 in 1990 to 118.40/100,000 in 2017. The trend of the prevalence rate in both genders grow higher in 2017 compared to the 1990, resulting in 141.6%, 209.8% and 189.0% for the studied three age groups (15-49, 50-69 and 70+ years old), respectively. The death rate increased in the age groups of 50-69 and 70+ years in both genders (8.6% and 31.0% respectively), in contrast to a decrease of death rate in the age group of 15-49 years old (-10.8%). Conclusions: China experienced a stunning increase in terms of incidence and prevalence rate of CRC from 1990 to 2017. To decrease the burden of CRC, prevention and management of known risk factors should be promoted through national polices.

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