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1.
Chemosphere ; 240: 124867, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542587

RESUMO

Phase transfer catalysts (PTCs) have been shown to be effective in lowering the limitation of mass transfer between aqueous oxidant MnO4- and NAPLs in in-situ chemical oxidation (ISCO) technologies for remediation of NAPLs. This work researched the effects of pentyltriphenylphosphonium bromide (PTPP, used as the representative PTC) for the enhancement of TCE oxidation, the extent of different treatment effects contributions and generalizability of phase transfer. Experimental results revealed that MnO4- exchanged with Br- in PTPP by ion exchange mechanism and then transferred to NAPL phase due to biphasic nature of PTPP-MnO4-. PTPP enhanced TCE dissolution in aqueous phase but had no significant effect on TCE solubilization. Enhanced TCE dissolution gradually weakened after 2.0 h and disappeared after 5.5 h, while the percentage of MnO4- in phase transfer was 14.8% at 7.5 h, which indicated that dissolution acceleration was only effective at initial stage of reaction (0-2.5 h). Therefore, persistent phase transfer process played the leading role in TCE remediation enhancement. Moreover, for different NAPL phase, more effective phase transfer could be achieved in NAPLs with higher solubility and weaker hydrophobicity. The best-fit polynomial relationship (R2 = 0.992) existed between the percentage amount of MnO4- transferred and the solubility of NAPL.

2.
Biomed Pharmacother ; 121: 109610, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31710894

RESUMO

Bromopyruvate (3-BrPA) is a glycolysis inhibitor that has been reported to have a strong anti-tumour effect in many human tumours. Several studies have reported that 3-BrPA could inhibit glioma progression; however, its role on the interstitial cells in the glioma microenvironment has not been investigated. In previous studies, we found that in the glioma microenvironment, glioma stem cells can induce the malignant transformation of macrophages and dendritic cells. In this study, we focused on the effects of 3-BrPA on malignantly transformed macrophages and dendritic cells. First, we found that 3-BrPA inhibited the proliferation of malignantly transformed macrophages and dendritic cells in a dose-dependent and time-dependent manner. Further study indicated that 3-BrPA significantly decreased extracellular lactate and inhibited the clone formation, migration and invasion of malignantly transformed macrophages and dendritic cells. Using an online database and a series of experiments, we demonstrated that 3-BrPA inhibits the malignant progression of malignantly transformed macrophages and dendritic cells via the miR-449a/MCT1 axis. These findings built experimental basis for new approach against glioma.

3.
J Cell Physiol ; 235(2): 1649-1662, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31392726

RESUMO

Hypoxia is a common pathological process caused by insufficient oxygen. Long noncoding RNAs (lncRNAs) have been proven to participate in this pathology. Hypoxia is reported to significantly reduce the secretion of tissue inhibitor of metalloproteinase 2 (TIMP2) and TIMP2 induces pheochromocytoma-12 (PC12) cell cycle arrest. Thus, our study aimed to explore the mechanism by which lncRNA maternally expressed gene 3 (MEG3) was implicated in hypoxia-induced PC12 cell injury through TIMP2 promoter methylation. To elucidate the potential biological significance of MEG3 and the regulatory mechanism between MEG3 and TIMP2, a hypoxia-induced PC12 cell injury model was generated. The hypoxia-exposed cells were subjected to a series of overexpression plasmids and short hairpin RNAs, followed by the measurement of levels of MEG3, TIMP2, lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxygen species (ROS), Bcl-2-associated X protein, B-cell lymphoma-2, and caspase-3, as well as the changes in MMP, cell proliferation, apoptosis, and cell cycle progression. On the basis of the findings, MEG3 was upregulated in hypoxia-injured PC12 cells. MEG3 recruited methylation proteins DNMT3a, DNMT3b, and MBD1 and accelerated TIMP2 promoter methylation, which in turn inhibited its expression. Moreover, PC12 cells following MEG3 silencing and TIMP2 overexpression exhibited significantly decreased levels of LDH, MDA, and ROS along with cell apoptosis, yet increased SOD and MMP levels, as well as cell cycle entry to the S phase and cell proliferation. In conclusion, MEG3 silencing suppresses hypoxia-induced PC12 cell injury by inhibiting TIMP2 promoter methylation. This study may provide novel therapeutic targets for hypoxia-induced injury.

4.
Sci Rep ; 9(1): 18122, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792298

RESUMO

B7-H6, a member of the B7 family molecules, participates in the clearance of tumor cells by binding to NKp30 on NK cells. B7-H6 expression level in esophageal squamous cell carcinoma (ESCC) and the clinical value remain unknown. The goal of this study was to determine the expression of B7-H6 in ESCC and further explore its clinical significance. We retrospectively collected the clinical data of 145 patients diagnosed with ESCC between January 2007 and December 2008. The expression of B7-H6 of the pathological tissue samples was detected by immunohistochemistry. The chi-square (χ2) test was used to analyse the relationships of B7-H6 and clinicopathological characteristics. Survival and hazard functions were estimated using the Kaplan-Meier method, and survival between groups was compared using the two-sided log-rank test. The Cox proportional hazards regression model was used to adjust for the risk factors related to overall survival (OS). 133/145 (91.72%) of the ESCC tissue samples exhibited B7-H6 expression. The expression level of B7-H6 was correlated with T stage (P = 0.036) and lymphatic metastasis status (P = 0.044). High B7-H6 expression (P = 0.003) was associated with a significantly worse OS than low B7-H6 expression. Multivariate Cox proportional hazards regression analysis demonstrated that tumour size (P = 0.021), B7-H6 expression (P = 0.025) and lymphatic metastasis status (P = 0.049) were independent prognostic factors of OS for ESCC. Collectively, our findings suggest that B7-H6 is widely expressed in ESCC samples. And B7-H6 may represent a predictor of poor prognosis for ESCC.

5.
J Magn Reson Imaging ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31785074

RESUMO

BACKGROUND: Central nervous system inflammation is associated with neurodegenerative diseases and is thought to play a part in the pathophysiological cascade leading to cognitive impairment. Madecassoside (MA) has shown potential for the treatment of neuroinflammation. Lipopolysaccharide (LPS) can be used to establish an animal model of cognitive dysfunction induced by neuroinflammation. Intravoxel incoherent motion (IVIM) may potentially provide diffusion and perfusion data. PURPOSE: To investigate the effect of MA on neurocognitive impairment induced by LPS in rats, and to explore the changes of brain microstructure and microcirculatory perfusion by IVIM imaging. STUDY TYPE: Prospective. POPULATION: Thirty-six male Sprague-Dawley rats were randomly divided into six groups (control group, sham operation group, LPS group, low-dose MA group, middle-dose MA group, and high-dose MA group) in a model of neurocognitive impairment induced by LPS (150 µg / 5 µL, 5 µL). FIELD STRENGTH/SEQUENCE: IVIM-DWI sequence at 3.0T MRI; the scan time was 2 minutes and 17 seconds. ASSESSMENT: The escape latency times of a Morris water maze test was used to evaluate the cognitive impairment rat model and the changes of learning ability of rats treated with different doses of MA (30 mg/kg, 60 mg/kg, 120 mg/kg). A GE postprocessing workstation (adw 4.5) was used to analyze the changes of each parameter (f value, D value, and D* value) in the IVIM data of each group. STATISTICAL TESTS: All the data were analyzed by one-way and two-way analysis of variance (ANOVA). RESULTS: The escape latency of the LPS group was significantly longer than the sham group (P = 0.05, 0.001, 0.006, and 0.042, respectively), and the high-dose group was significantly shorter than the LPS group on the sixth day (P = 0.034). Compared with the control group, the D values and f values of cerebral cortex and hippocampus were decreased significantly in the LPS group (P = 0.043 and 0.003; P = 0.029 and 0.016, respectively). With the increasing dose of MA, the D and f values of hippocampus and cortex increased, and there was a significant difference between the high-dose MA group and LPS group (D values: P = 0.038, 0.036; f values: P = 0.048, 0.039, respectively) DATA CONCLUSION: MA can improve the cognitive impairment induced by LPS by reducing neuroinflammation, and the changes of microcirculation and microperfusion in the brain tissue of these rats can be detected by IVIM imaging. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 4 J. Magn. Reson. Imaging 2019.

6.
Int J Biol Macromol ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31790738

RESUMO

In this study, the antibacterial activities of colloidal chitosan, chitosan solution, and chitooligosaccharide solution were evaluated against Xanthomonas axonopodis pv. glycines grown in peptone sucrose broth (PSB) medium. Treatment with colloidal chitosan (0.01, 0.025, and 0.05%) inhibited X. axonopodis pv. glycines growth only until 36 h. Thin-layer chromatography analysis detected some metabolites, consistently with the cell growth pattern. Two chitooligosaccharides (1-3 kDa and 5-10 kDa) dissolved in distilled water and acetic acid did not exhibit antibacterial activity against X. axonopodis pv. glycines at all tested concentrations (0, 0.001, 0.005, 0.01, 0.015, 0.02, 0.025, and 0.05%). Compared to the control, the chitosan solution decreased X. axonopodis pv. glycines cell growth by 58.7% and 99.0% at concentrations of 0.015% and 0.02%, respectively, after 3 d of incubation. The chitosan solution exhibited the highest antibacterial activity at pH 6.5. However, the antibacterial activity of chitosan decreased in the presence of NaCl and MgCl2.

7.
Cancer Imaging ; 19(1): 80, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791411

RESUMO

BACKGROUND: Thymoma is a rare tumor that originates from thymic epithelial cells and is usually associated with myasthenia gravis. Radiofrequency ablation (RFA) is a minimally invasive and curative treatment for other tumors, but RFA has not been used for the early treatment of thymoma. METHODS: The current study included 13 patients with stage I thymoma who were not candidates for surgical resection or video-assisted thoracoscopic surgery (VATS). All patients underwent first-line CT-guided percutaneous RFA. The feasibility and therapeutic effects of the intervention were thoroughly documented. RESULTS: All tumors were completely ablated (13 / 13, 100%). During follow-up (median 80.5 months, range, 64.6-116.9 months), only 1 of the 13 patients had recurrence of thymoma (1 / 13, 7.7%) at 35.5 months after the initial ablation. There were no surgery-related deaths after RFA treatment. The most common complications were fever (13 / 13, 100%) and pain (13 / 13, 100%). There was only one patient who occurred severe puncture-related bleeding during the procedure that needed blood transfusion and intravascular embolization of the punctured-injured vessel. CONCLUSION: CT-guided percutaneous RFA for treatment of stage I thymoma is associated with minor trauma, few complications and good treatment outcomes.

8.
Food Chem ; : 125894, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31787396

RESUMO

This work aims to use defatted rice bran albumin (RBA) for delivering epigallocatechin gallate (EGCg). The mode of RBA particle size shifted from 142 nm to 164 nm upon interaction with EGCg. Hydrophobic interaction is the major force between EGCg and RBA resulted in the formation of EGCg-RBA complex based on fluorescence quenching. Upon incorporation into RBA, the recovery of EGCg in pH 7.4 phosphate buffer was elevated by 2 folds. The recovery of EGCg in EGCg-RBA was 18.9% after 2 h intestinal digestion, being higher than 7.6% of native EGCg. The pretreatments of HT-29 cells with EGCg, RBA and EGCg-RBA significantly repressed the transcriptional activation of mitogen-activated protein kinase 14, nuclear transcription factor-κB, and activators of transcription 3 as stimulated with interleukin-1ß afterwards, leading to attenuated expressions of corresponding downstream genes. Antioxidant ability importantly functioned in anti-inflammation. RBA is a promising vehicle with inherent anti-inflammatory property for stabilizing and delivering EGCg.

9.
Sci Rep ; 9(1): 18343, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31798009

RESUMO

The objective of this study was to evaluate the bidirectional association between asthma and migraines using control subjects matched by demographic factors. The Korean Health Insurance Review and Assessment Service - National Sample Cohort from 2002 to 2013 was used. In study I, 113,059 asthma participants were matched with 113,059 control I participants. In study II, 36,044 migraine participants were matched with 114,176 control II participants. The hazard ratios (HRs) of migraines in the asthma patients (study I) and asthma in the migraine patients (study II) were analyzed using stratified Cox proportional hazard models after adjusting for depression and the Charlson comorbidity index. In study I, 5.3% (6,017/ 113,059) of the asthma group and 3.4% (3,806/ 113,059) of the control I group had migraines (P < 0.001). The asthma group demonstrated an adjusted HR of 1.47 for migraine (95% confidence interval (CI) = 1.41-1.53, P < 0.001). In study II, 15.4% (5,548/36,044) of the migraine group and 10.6% (15,271/144,176) of the control group had asthma (P < 0.001). The migraine group showed an adjusted HR of 1.37 for asthma (95% CI = 1.33-1.41, P value < 0.001). Asthma and migraines are reciprocally associated.

10.
Food Funct ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799531

RESUMO

Alzheimer's disease (AD) is a chronic neurodegenerative disease, and typical pathologic findings include abnormally hyperphosphorylated tau aggregation and neurofibrillary tangles. Insulin resistance and hyperglycaemia have been proposed as risk factors for AD development. As the maintenance of optimal blood glucose level is an important indicator of diabetes mellitus (DM) treatment, diet control is essential. AMPK is a crucial sensor of cellular bioenergetics for controlling anabolic and catabolic metabolism. Since AMPK is a direct regulator of tau phosphorylation, we hypothesized that strict diet control to achieve euglycaemia affects tau protein phosphorylation through increased AMPK activity in the hippocampus of DM rats. To test this hypothesis, we generated insulin-deficient DM rats by subtotal pancreatectomy and the animals were categorized into the diet-restriction (R) group and ad libitum (AL) feeding group. We found that tau phosphorylation was significantly higher in the R group than that in the sham-control (C) or AL group. AMPK activity in the R group was significantly higher than that in the C or AL group, as expected. Furthermore, the R group showed more critical tau pathology in the hippocampus than the other groups. These results suggest that diet control to achieve euglycaemia in an insulin-deficient DM condition may be harmful because of the greater possibility of AD development through increased tau phosphorylation by AMPK activation in the hippocampus.

11.
Mod Pathol ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700162

RESUMO

Venous invasion is three times more common in pancreatic cancer than it is in other major cancers of the gastrointestinal tract, and venous invasion may explain why pancreatic cancer is so deadly. To characterize the patterns of venous invasion in pancreatic cancer, 52 thick slabs (up to 5 mm) of tissue were harvested from 52 surgically resected human ductal adenocarcinomas, cleared with a modified iDISCO method, and labeled with fluorescent-conjugated antibodies to cytokeratin 19, desmin, CD31, p53 and/or e-cadherin. Labeled three-dimensional (3D) pancreas cancer tissues were visualized with confocal laser scanning or light sheet microscopy. Multiple foci of venous and even arterial invasion were visualized. Venous invasion was detected more often in 3D (88%, 30/34 cases) than in conventional 2D slide evaluation (75%, 25/34 cases, P < 0.001). 3D visualization revealed pancreatic cancer cells crossing the walls of veins at multiple points, often at points where preexisting capillary structures bridge the blood vessels. The neoplastic cells often retained a ductal morphology (cohesive cells forming tubes) as they progressed from a stromal to intravenous location. Although immunolabeling with antibodies to e-cadherin revealed focal loss of expression at the leading edges of the cancers, the neoplastic cells within veins expressed e-cadherin and formed well-oriented glands. We conclude that venous invasion is almost universal in pancreatic cancer, suggesting that even surgically resectable PDAC has access to the venous spaces and thus the ability to disseminate widely. Furthermore, we observe that sustained epithelial-mesenchymal transition is not required for venous invasion in pancreatic cancer.

12.
J Affect Disord ; 262: 126-132, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31733456

RESUMO

BACKGROUND: Few studies have investigated the bidirectional association between psoriasis and depression. The aim of our study was to identify the association between psoriasis and depression. METHODS: Data collected by the Korean Health Insurance Review and Assessment from 2002 to 2013 were used. In study I, psoriasis patients (n = 10,932) were matched 1:4 with control I group participants. In study II, depression patients (n = 60,383) were matched 1:4 with control II group participants. Matching was performed for age, sex, income, and region of residence. The stratified Cox-proportional hazard model was used to calculate the hazard ratio (HR) with crude and adjusted models. RESULTS: In study I, the adjusted HR for depression was 1.13 (95% confidence interval (CI) = 1.03-1.24) in the psoriasis group compared to the control I group. In study II, the adjusted HR for depression was 1.11 (95% CI = 1.00-1.22) in the depression group compared to the control II group. In the subgroup analyses, the adjusted HRs for depression were 1.24 (95% CI = 1.00 - 1.53) in females aged < 40 years and 1.31 (95% CI = 1.04 - 1.66) in males aged ≥ 60 years. In the subgroup analyses from study II, the adjusted HRs for psoriasis were 1.56 (95% CI = 1.15 - 2.12) in males aged < 40 years and 1.35 (95% CI = 1.04 - 1.75) in males aged ≥ 60 years. CONCLUSIONS: We suggest that psoriasis and depression might have a bidirectional association.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31742641

RESUMO

OBJECTIVE: To investigate the bidirectional relation between RA and depression. METHODS: Data from the Korean Health Insurance Review and Assessment Service - National Sample Cohort from 2002 to 2013 were analysed. Patients ≥20 years of age were included. Study I was conducted with 38 087 depression patients and 152 348 matched control participants. Study II was conducted with 7385 RA patients and 29 540 matched control participants. Stratified Cox proportional hazards models were used to analyse the hazard ratios (HRs) for depression and RA (study I) and for RA and depression (study II). The data were adjusted by the Charlson comorbidity index; rheumatic disease was excluded. Subgroups were also analysed according to age and sex. RESULTS: A total of 0.7% (1260/38 087) of the depression group and 0.6% (883/152 348) of the control I group had RA (P = 0.02). The HR for RA in the depression group was not significantly higher than that in control I group. In study II, 5.5% (408/7385) of the RA group and 4.3% (1246/29 540) of the control II group presented with depression (P < 0.001). The RA patients showed an adjusted depression HR that was 1.20 times higher (95% CI 1.07, 1.34; P = 0.002) than that of the control group. The >30-years-old and women subgroups of RA patients showed higher depression HRs than the control subgroups. CONCLUSION: RA increased the risk of depression; however, depression did not increase the risk of RA in the Korean adult population.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31668919

RESUMO

The enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases 3 (PFKFB3) catalyzes the first committed rate-limiting step of glycolysis and is upregulated in cancer cells. The mechanism of PFKFB3 expression upregulation in cancer cells has not been fully elucidated. The PFKFB3 3'-UTR is reported to contain AU-rich elements (AREs) that are important for regulating PFKFB3 mRNA stability. However, the mechanisms by which PFKFB3 mRNA stability is determined by its 3'-UTR are not well known. We demonstrated that tristetraprolin (TTP), an ARE-binding protein, has a critical function regulating PFKFB3 mRNA stability. Our results showed that PFKFB3 mRNA contains three AREs in the 3'-UTR. TTP bound to the 3rd ARE and enhanced the decay of PFKFB3 mRNA. Overexpression of TTP decreased PFKFB3 expression and ATP levels but increased GSH level in cancer cells. Overexpression of PFKFB3 cDNA without the 3'-UTR rescued ATP level and GSH level in TTP-overexpressing cells. Our results suggested that TTP post-transcriptionally downregulated PFKFB3 expression and that overexpression of TTP may contribute to suppression of glycolysis and energy production of cancer cells in part by downregulating PFKFB3 expression.

15.
Mol Carcinog ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31782573

RESUMO

Gartanin, a 4-prenylated xanthone, has been identified from the purple mangosteen fruit as a potent growth inhibitor of various cancer cell lines, including prostate cancer. However, much of Gartanin's anticancer mechanism remains unknown. We have discovered that Gartanin docked onto the regulatory subunit of the precursor cell-expressed developmentally downregulated 8 (NEDD8)-activating enzyme (NAE) complex and next to the NEDD8 binding complex, which leads to inhibit NEDD8 conjugations to both Cullin1 and Ubc12 in prostate cancer cell lines and Ubc12 NEDDylation in an in vitro assay. The S phase kinase-associated protein (Skp2) and F-box and WD-repeat domain-containing 2 (FBXW2), the NEDD8 family members of E3 ubiqutin ligases, were also downregulated and upregulated by Gartainin, respectively. Knock-down of NEDD8 expression by short harpin (Sh) RNAs blocked or attenuated these effects of Gartainin. Finally, Gartanin demonstrated its ability to inhibit growth of prostate cancer lines via autophagy initiation. Our data support that Gartanin is a naturally occurring NEDDylation inhibitor and deserves further investigation for prostate cancer prevention and treatment.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31767150

RESUMO

Recent research revealed that doxorubicin (DOX) decreased expression of programmed death-ligand 1 (PD-L1) in cancer cells. However, the detailed mechanisms underlying this effect are not well established. Here, we demonstrate that doxorubicin down-regulates PD-L1 expression through induction of AU-rich element (ARE) binding protein tristetraprolin (TTP) in cancer cells. PD-L1 mRNA contain three AREs within its 3'UTR. Doxorubicin induced expression of TTP, increased TTP binding to the 3rd ARE of the PD-L1 3'UTR, and increased decay of PD-L1 mRNA. Inhibition of TTP abrogates the inhibitory effect of doxorubicin on PD-L1 expression. Our data suggest that TTP plays a key role in doxorubicin-mediated down-regulation of PD-L1 by enhancing degradation of PD-L1 mRNA in cancer cells.

17.
Sci Rep ; 9(1): 16897, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729445

RESUMO

X-ray coronary angiography is a primary imaging technique for diagnosing coronary diseases. Although quantitative coronary angiography (QCA) provides morphological information of coronary arteries with objective quantitative measures, considerable training is required to identify the target vessels and understand the tree structure of coronary arteries. Despite the use of computer-aided tools, such as the edge-detection method, manual correction is necessary for accurate segmentation of coronary vessels. In the present study, we proposed a robust method for major vessel segmentation using deep learning models with fully convolutional networks. When angiographic images of 3302 diseased major vessels from 2042 patients were tested, deep learning networks accurately identified and segmented the major vessels in X-ray coronary angiography. The average F1 score reached 0.917, and 93.7% of the images exhibited a high F1 score > 0.8. The most narrowed region at the stenosis was distinctly captured with high connectivity. Robust predictability was validated for the external dataset with different image characteristics. For major vessel segmentation, our approach demonstrated that prediction could be completed in real time with minimal image preprocessing. By applying deep learning segmentation, QCA analysis could be further automated, thereby facilitating the use of QCA-based diagnostic methods.

19.
Med Hypotheses ; 134: 109445, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31669757

RESUMO

Human otoliths, primarily formed from salts of calcium and carbonate, are different from bones of the skeleton, which are composed of calcium phosphate. The echinoderms, which share the earliest common ancestor with us, began to protect the body by making an endoskeleton out of calcium and carbon dioxide dissolved in the sea. In subsequent vertebrates, aerobic respiration supported strong muscle activity, but an occasional shortage of oxygen led to low pH due to the accumulation of lactate produced by anaerobic respiration, increasing the risk of melting bones composed of calcium carbonate. So, all vertebrates used calcium phosphate to increase bone strength, having a stronger ionic bonding than calcium carbonate. But otoliths, which are in the inner ear and thereby not connected to muscles, still use calcium carbonate. Benign paroxysmal positional vertigo (BPPV) is a disorder in which otoliths detached from the utricle enter the semicircular canals and cause a sense of rotation. Otoliths, the calcium carbonate ear bones retaining a long evolutionary history, can be easily broken at low pH. During sleep, shallow breathing produces mild respiratory acidosis and low pH in the blood. Since otoliths are corroded at low pH during nighttime, BPPV occurs frequently in the morning. In addition, diabetes mellitus or gout often decreases pH in the blood and increases the occurrence of BPPV.

20.
Anal Biochem ; 589: 113494, 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31693872

RESUMO

Identification of DNA-binding proteins (DNA-BPs) is a hot issue in protein science due to its key role in various biological processes. These processes are highly concerned with DNA-binding protein types. DNA-BPs are classified into single-stranded DNA-binding proteins (SSBs) and double-stranded DNA-binding proteins (DSBs). SSBs mainly involved in DNA recombination, replication, and repair, while DSBs regulate transcription process, DNA cleavage, and chromosome packaging. In spite of the aforementioned significance, few methods have been proposed for discrimination of SSBs and DSBs. Therefore, more predictors with favorable performance are indispensable. In this work, we present an innovative predictor, called SDBP-Pred with a novel feature descriptor, named consensus sequence-based K-segmentation position-specific scoring matrix (CSKS-PSSM). We encoded the local discriminative features concealed in PSSM via K-segmentation strategy and the global potential features by applying the notion of the consensus sequence. The obtained feature vector then input to support vector machine (SVM) with linear, polynomial and radial base function (RBF) kernels. Our model with SVM-RBF achieved the highest accuracies on three tests namely jackknife, 10-fold, and independent tests, respectively than the recent method. The obtained prediction results illustrate the superlative prediction performance of SDBP-Pred over existing studies in the literature so far.

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