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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117433, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31390579

RESUMO

Detecting NAA in food has drawn intense attention as it has imposed significant threat to people's health and the growth of food industry. Over the past few years, great importance has been attached to the application of copper nanomaterials as fluorescent probe to food and environmental detection. Here, the simple, rapid, cost effective and water soluble fluorescent copper nanoparticles were synthesized with chemical reduction sonochemical assisted method for highly selective and sensitive detection of α-naphthaleneacetic acid (NAA) by using 2-mercaptobenzothiazole (MBT) as a protecting agent and polyvinylpyrrolidone (PVP) as a stabilizing agent (MBT-PVP CuNPs). The resultant CuNPs has a spherical shape with an average diameter of 10-15 nm and strong fluorescent pink emission characteristic peak at 580 nm upon 334 nm excitation. Interestingly, upon the addition of NAA, the fluorescence of MBT-PVP CuNPs can be effectively quenched for the reason that NAA could interact with MBT via hydrogen bonding and conform copper-NAA clathrate with Cu+ via coordination bond, which shows a good linearity in the range of NAA from 0.5 to 50 µM and with a detection limit of 9.6 nM. Moreover, the prepared probe has good selectivity for NAA detection over other co-existing molecules. It is worth mentioning that this method has been successfully applied to authentic comestible sample analysis and obtained satisfying and promising results, which indicates that this strategy is likely to have a promising application potential for NAA detection in the field of food safety.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117463, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31421349

RESUMO

Real-time process quality control of ramulus cinnamomi (cassia twig) is still a challenge in pharmaceutical industry. Rapid critical quality attribute (CQA) determination of ramulus cinnamomi is essential for quality control. Microscale thermophoresis (MST) was used to investigate the CQA of ramulus cinnamomi by the interaction with biomacromolecule. There was a good affinity between cinnamaldehyde and human serum albumin (HSA) with Ka as 2.1722×103mol/L. It was an excellent combination of similarity to ibuprofen with same binding force as discovered as hydrogen bond and van der Waals force. Furthermore, regarding cinnamaldehyde as CQA, on-line near-infrared was used to monitor pilot extraction process of ramulus cinnamomi combined with high performance liquid chromatography (HPLC). Quantitative model was established with Rpre2 as 0.9798 and RMSECV as 0.0993, suggesting the NIR model was so robust and accurate for pilot process quality control. This method provided a perfect guideline for rapid CQA determination and real-time process quality control of Chinese materia medica (CMM) based on a vital CQA.

3.
Food Chem ; 307: 125529, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644982

RESUMO

Ten lactic acid bacteria (LAB) strains of different species isolated from Chinese traditional sourdough were investigated on their volatile compounds in sourdough fermentation. Sourdoughs fermented with different LAB species were analyzed by principal component analysis (PCA) based on their volatiles. Furthermore, the in situ gene expressions of Lactobacillus sanfranciscensis during sourdough fermentation were investigated by using RNA sequencing for the first time. PCA could discriminate between the sourdoughs fermented by homofermentative and heterofermentative LAB, the former containing more aldehydes and ketones with more than 6 carbon atoms, while the latter featuring ethanol and esters. The Lactobacillus plantarum-fermented sourdough was characterized by high C4-C6 volatiles content, while L. sanfranciscensis showed a unique volatile profile without explicit explanatory compounds. The RNA sequencing suggested that, compared to the sourdough fermented for 6 h, L. sanfranciscensis enhanced carbohydrate metabolism and self-protection activities, but decreased cell proliferation in sourdough at 12 h.

4.
Biomed Pharmacother ; 121: 109622, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707340

RESUMO

BACKGROUND: Previous study has demonstrated that long noncoding RNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) was abnormally expressed in diabetic nephropathy (DN). However, the underlying mechanism that allows CDKN2B-AS1 in the progression of DN remains to be further elucidated. METHODS: Peripheral blood cells of 24 diabetes patients with DN and 20 without DN were collected. Human glomerular mesangial cells (HGMC) were cultured in high glucose or low glucose medium. The expression levels of CDKN2B-AS1, microRNA (miR)-424-5p and high mobility group AT hook 2 (HMGA2) were detected by quantitative real-time polymerase chain reaction or western blot. The target association between miR-424-5p and CDKN2B-AS1 or HMGA2 was confirmed by dual-luciferase reporter and RNA immunoprecipitation assays. Cell proliferation, extracellular matrix (ECM) accumulation and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling were investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and western blot, respectively. RESULTS: CDKN2B-AS1 expression was up-regulated and miR-424-5p level was down-regulated in peripheral blood of DN patients and high glucose-treated HGMC cells. CDKN2B-AS1 was validated as a sponge of miR-424-5p. Silence of CDKN2B-AS1 repressed proliferation and ECM accumulation by increasing miR-424-5p. HMGA2 was a target of miR-424-5p and miR-424-5p overexpression inhibited proliferation, ECM accumulation and PI3K/AKT pathway by targeting HMGA2. Moreover, knockdown of CDKN2B-AS1 inhibited HMGA2 expression and PI3K/AKT pathway by increasing miR-424-5p. CONCLUSION: Knockdown of CDKN2B-AS1 suppressed proliferation, ECM accumulation and PI3K/AKT signaling by increasing miR-424-5p and decreasing HMGA2 in high glucose-treated HMGC cells.

5.
Anal Chim Acta ; 1094: 130-135, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761039

RESUMO

Quantification of plasma membrane proteins (PMPs) is crucial for understanding the fundamentals of cellular signaling systems and their related diseases. In this work, a super-quadruplex scaffold was designed to regulate assembly of oligonucleotide-grafted AIEgens for detection of PMPs. The nonfluorescence oligonucleotide-grafted AIEgen (Oligo-AIEgen) was firstly synthesized by attaching the AIEgen to 3'-terminus of the oligonucleotide through click chemistry. Meanwhile, the tetramolecular hairpin-conjugated super-quadruplex (THP-G4) as cleavage element and signal enhancement scaffold composited of three elements: a substrate sequence of DNAzyme in the loop region, partial hybridization region in the stem, and six guanine nucleotides to form G-quadruplex. Once the DNAzyme was anchored on the specific PMPs through aptamer-protein recognition, the substrate sequence on the loop of THP-G4 was cleaved by DNAzyme with the aid of cofactor MnII, resulting in the conformation switch of THP-G4 to the activated G-quadruplex scaffold. The latter could assemble Oligo-AIEgens to generate aggregation-induced emission (AIE) enhancement, resulting in a simple and sensitive strategy for detection of membrane proteins. Moreover, the DNAzyme continuously cut the next THP-G4 to achieve recycling amplification. Under the optimized conditions, this AIE-based strategy exhibited good linear relationship with the logarithm of MUC1 concentration from 0.01 to 10 µg mL-1 with the limit of detection down to 4.3 ng mL-1. The G4-assembled AIEgens provides a universal platform for detecting various biomolecules and a proof-of concept for AIE biosensing.

6.
Sci Total Environ ; 701: 134979, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31733400

RESUMO

Floods are one of the most devastating types of disasters that cause loss of lives and property worldwide each year. This study aimed to evaluate and compare the prediction capability of the naïve Bayes tree (NBTree), alternating decision tree (ADTree), and random forest (RF) methods for the spatial prediction of flood occurrence in the Quannan area, China. A flood inventory map with 363 flood locations was produced and partitioned into training and validation datasets through random selection with a ratio of 70/30. The spatial flood database was constructed using thirteen flood explanatory factors. The probability certainty factor (PCF) method was used to analyze the correlation between the factors and flood occurrences. Consequently, three flood susceptibility maps were produced using the NBTree, ADTree, and RF methods. Finally, the area under the curve (AUC) and statistical measures were used to validate the flood susceptibility models. The results indicated that the RF method is an efficient and reliable model in flood susceptibility assessment, with the highest AUC values, positive predictive rate, negative predictive rate, sensitivity, specificity, and accuracy for the training (0.951, 0.892, 0.941, 0.945, 0.886, and 0.915, respectively) and validation (0.925, 0.851, 0.938, 0.945, 0.835, and 0.890, respectively) datasets.

7.
J Environ Sci (China) ; 87: 213-227, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791494

RESUMO

Beijing-Tianjin-Hebei (BTH) and its surrounding areas are very important to air pollution control in China. To analyze the characteristics of BTH and its surrounding areas of China, we collected 5,641,440 air quality data from 161 air monitoring stations and 37,123,000 continuous monitoring data from air polluting enterprises in BTH and surrounding cities to establish an indicator system for urban air quality portraits. The results showed that particulate matter with aerodynamic diameters of <2.5 µm (PM2.5), particulate matter with aerodynamic diameters of <10 µm (PM10) and SO2 improved significantly in 31 cities from 2015 to 2018, but ozone deteriorated. Air quality in BTH and the surrounding areas showed obvious seasonal characteristics, among which PM2.5, PM10, SO2, and NO2 showed a "U" type distribution from January to December, while O3 had an "inverted U" distribution. The hourly changes in air quality revealed that peaks of PM2.5, PM10 and NO2 appeared from 8:00 to 10:00, while those for O3 appeared at 15:00-16:00. The exposure characteristics of the 31 cities showed that six districts in Beijing had the highest air quality population exposure, and that exposure levels in Zhengzhou, Puyang, Anyang, Jincheng were higher than the average of the 31 investigated cities. Additionally, multiple linear regression revealed a negative correlation between meteorological factors (especially wind and precipitation) and air quality, while a positive correlation existed between industrial pollution emissions and air quality in most of BTH and its surrounding cities.

8.
Cancer Lett ; 468: 27-40, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604115

RESUMO

Patients with recurrent nasopharyngeal carcinoma (NPC) have more co-existing distant metastasis than those of no-recurrence and are more likely to suffer distant metastasis after re-irradiation than patients with newly diagnosed NPC. However, the relationship between radioresistance and distant metastasis and the mechanisms involved in radioresistance-associated metastasis are still unclear. In this study, we proved that C-C motif chemokine ligand 2 (CCL2) expression was significantly elevated in HONE1-IR cells and recurrent NPC tumour. Inhibition of CCL2 enhanced sensitivity to radiotherapy in NPC cells. Moreover, autocrine CCL2 promoted NPC cell adaptive radioresistance, metastasis and epithelial-mesenchymal transition. Additionally, p53 activated CCL2 transcription. High CCL2 expression was highly associated with poorer locoregional recurrence free survival, progression free survival and overall survival in patients with newly diagnosed NPC. Notably, high CCL2 expression was an independent prognostic factor for distant metastasis free survival in recurrent NPC patients. Our results provide insights into the autocrine signalling mechanisms of CCL2 and suggest that inhibition of autocrine CCL2 may be a candidate treatment strategy for management of radioresistant NPC.

9.
Food Chem ; 308: 125599, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648098

RESUMO

In this work, sequential electrospinning was utilized to fabricate a multilayer film with ethylcellulose nanofibers as the outer layer and curcumin-loaded gelatin nanofibers as the inner layer. Field-emission scanning electronic microscopy observations showed that the outer and inner layers had a smooth surface and clear boundary. The hydrophobic outer layers decreased the water vapor permeability and improved the water contact resistance of the hydrophilic inner layer, and the intimate interactions of hydrogen bonds between two adjacent layers enhanced the thermal stability. The multilayer film exhibited a sustained release manner of the encapsulated curcumin for 96 h, compared to the burst release within 30 min from the gelatin film. In addition, the antioxidant activities of the released curcumin from the multilayer film were well retained within 96 h. These results suggested that the multilayer nanofibrous film fabricated by sequential electrospinning has potential applications in bioactive encapsulation and controlled release.

10.
Methods Mol Biol ; 2057: 103-112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31595474

RESUMO

Nitrogen (N2) is the most necessary element in the atmosphere, it is an energetic micronutrient for plant growth and development after water, besides its key role in chlorophyll production, which is crucial for photosynthesis process. Biological nitrogen fixation is measured to be the most potent method to deliver a fixed way of nitrogen to the plants. Plant depends on free-living and symbiotic microbes present in the soil for nitrogen because it cannot be absorbed by the plant itself directly from the atmosphere. Many techniques were reported in the laboratory for nitrogen estimation till now, but Kjeldahl digestion and acetylene reduction assay (ARA) techniques became the most popular. In this chapter, we focus on the most common and popular methods used to determine plant N2; awareness obtained through the wide application of these methods should offer the source for the N2 fixation rate in agriculture system.

11.
J Cell Physiol ; 235(2): 1051-1064, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31276200

RESUMO

Mitofusin 2 (MFN2) is a regulatory protein participating in mitochondria dynamics, cell proliferation, death, differentiation, and so on. This study aims at revealing the functional role of MFN2 in the pluripotency maintenance and primitive differetiation of embryonic stem cell (ESCs). A dox inducible silencing and routine overexpressing approach was used to downregulate and upregulate MFN2 expression, respectively. We have compared the morphology, cell proliferation, and expression level of pluripotent genes in various groups. We also used directed differentiation methods to test the differentiation capacity of various groups. The Akt signaling pathway was explored by the western blot assay. MFN2 upregulation in ESCs exhibited a typical cell morphology and similar cell proliferation, but decreased pluripotent gene markers. In addition, MFN2 overexpression inhibited ESCs differentiation into the mesendoderm, while MFN2 silencing ESCs exhibited a normal cell morphology, slower cell proliferation and elevated pluripotency markers. For differentiation, MFN2 silencing ESCs exhibited enhanced three germs' differentiation ability. Moreover, the protein levels of phosphorylated Akt308 and Akt473 decreased in MFN2 silenced ESCs, and recovered in the neural differentiation process. When treated with the Akt inhibitor, the neural differentiation capacity of the MFN2 silenced ESCs can reverse to a normal level. Taken together, the data indicated that the appropriate level of MFN2 expression is essential for pluripotency and differentiation capacity in ESCs. The increased neural differentiation ability by MFN2 silencing is strongly related to the Akt signaling pathway.

12.
Methods Mol Biol ; 2050: 13-19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468475

RESUMO

Generally, electroporation of in vitro cells is performed under very high electric fields to overcome the physical barrier of plasma membrane. Since traditional electroporation techniques make use of very high voltages, which is critical to cell viability, this study presents a microfluidic platform able to perform cell membrane electroporation with the application of low voltages (1.5-2 V). The platform is manufactured based on the milling by mean of focused ionic beam, which offers an established approach to fabricate ordered arrays of 3D gold hollow nanoelectrodes protruding from an insulating substrate. The novelty of this fabrication relies on the fact that the nanoelectrodes used for electroporation are simultaneously metallic, hollow and communicate through its nanochannels with an isolated microfluidic chamber beneath the device. Adherent cultured cells on the nanoelectrodes can be electroporated in this platform, and molecules can be selectively delivered only inside the porated cells.

13.
J Nanosci Nanotechnol ; 20(3): 1859-1865, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492353

RESUMO

As oxidation is inevitable during application of microwave absorbing materials (MAM) exposed to oxygen-containing atmosphere at elevated temperatures. The investigations concerning influences of oxidation on microstructure and microwave absorption (MA) properties are of great significance. Aiming to better regulating MA for Si3N4-based ceramics serviced in high temperature environment, the evolution of MA properties of SiCw/Si3N4 composites (SwSN) after oxidation at 1200 °C in ambient air for short time was studied. It was found that after oxidation for 7.5 h, both the real and imaginary permittivity of SwSN showed only slight decrease due to good oxidation protection provided by dense SiO2 layer formed on the surface. Moreover, SwSN after short-time of oxidation also showed an almost negligible decline in MA properties. SwSN which has good oxidation resistance and stable microwave attenuation abilities was subjected to oxidation at 1200 °C for short time. The results showed its favorable and potential applications in high-temperature microwave absorption fields.

14.
Clin Chim Acta ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794763

RESUMO

Very long-chain acyl-coenzyme A dehydrogenase deficiency (VLCAD deficiency), a rare autosomal recessive disorder, is characterized by hypoketotic hypoglycemia, cardiomyopathy, liver damage, and myopathy. VLCAD deficiency is caused by defects of ACADVL gene, which encodes VLCAD protein. The aim of this study was to determine the clinical, biochemical, prognosis and mutation spectrum of patients with VLCAD deficiency in mainland China. A total of Six families visited us, four patients (2 boys and 2 girls) were admitted in hospital due to liver dysfunction, hypoglycemia, and positive newborn screen result. The parents of the other two patients (2 girls) visited us for genetic consultation after their children's death. All the six patients had elevated level of serum tetradecenoylcarnitine (C14:1-carnitine), four of them showed decreased free carnitine (C0) level, and three had dicarboxylic aciduria. Eight types of mutations of the ACADVL gene were detected, three of them are novel, including c.563G>A (p.G188D) c.1387G>A (p.G463R) and c.1582_1586del (p.L529Sfs*31). The p.R450H mutation accounts for 9/52 alleles (5/40 in previous study of 20 unrelated patients, and 4/12 in this study) of genetically diagnosed Chinese VLCAD deficiency cases. The four alive patients (Patient 1-4) responded well to diet prevention and drug therapy with stable hepatic dysfunction condition. In conclusion, we describe three novel mutations of the ACADVL gene among six unrelated families with VLCAD deficiency. Moreover, we suggest that the p.R450H may be a potential hotspot mutation in the Chinese population.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31790202

RESUMO

Dual-band electrochromic devices (DBEDs) which can selectively modulate near-infrared (NIR) and visible (VIS) light transmittance through electrochromism, have gained increasing interest as a building energy saving technology. The technology is strongly dependent on the progress in electrochromic materials. Most current research has focused on the dual-band properties of the cathode materials, leaving the charge-balancing anode materials under-explored by comparison. This is a report of our study on the suitability of tin-doped indium oxide (ITO) nanocrystals (NCs) as a capacitive anode material for DBEDs. The ITO NCs are electrically conductive and VIS light transparent throughout the device operating range. As a result, they would not affect the NIR-selective modulation of the electrochromic device like most other anode materials do. The high surface area and good conductivity of the ITO NCs facilitate the adsorption/desorption of anions; thereby increasing their effectiveness as an ion storage thin film on the anode to balance the cathode charge. The best DBED prototype assembled from an ITO NC anode and a WO3-x cathode showed effective and independent control of VIS light and NIR transmittance with high optical modulation (71.1 % at 633 nm, 58.1% at 1200 nm), high coloration efficiency (95 cm2 C-1 at 633nm, 220 cm2 C-1 at 1200 nm), fast switching speed, good bistability and cycle stability.

16.
Child Abuse Negl ; 99: 104268, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31791008

RESUMO

BACKGROUND: Intimate partner violence (IPV) affects 1 in 3 US women with the effects of IPV detectable for several generations. While IPV is known to have significant impacts on maternal-child outcomes, little is known about the mother's perspectives of the interplay between perinatal IPV exposure, parenting styles, and safety strategies. METHODS: This secondary analysis of semi-structured, longitudinal qualitative interview data explored with pregnant women their histories of IPV, their parenting practices, and safety strategies. Data were derived from a randomized controlled trial, DOVE, with 22 interviews from 11 women collected during pregnancy and 12 or 24 months postpartum. RESULTS: Data were analyzed using constant comparative analysis resulting in three themes: "broken spirit," "I want better for my kids and me," and "safety planning as an element of parenting." Women described at baseline having a "broken spirit" due to their experiences with household and family chaos and childhood abuse. However, when mothers ended the abusive relationship, they described a better life and several strategies to protect themselves and their children. During their final interviews, mothers discussed how their lives improved after ending the relationship as well as safety planning strategies they employed like looking for "red flags" in potential partners, struggles with finding trustworthy childcare, and stockpiling money should they choose to end the relationship. CONCLUSION: These rich data add new information about how mothers of very young children navigate difficult parenting and safety decisions in the context of lifetime traumatic events and provide insights relevant for practice and research with this highly-vulnerable group of IPV survivors.

17.
J Environ Sci (China) ; 86: 203-212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787185

RESUMO

Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research topic. Herein, a rationally designed a Cu(II)-based metal-organic gel (Cu-MOG) with a nanoporous 3D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic dyes. The Cu-MOG exhibited high efficiency, with an adsorption capacity of up to 650.32 mg/g, and rapid adsorption efficiency, with the ability to adsorb 80% of Neutral Red within 1 min. The high adsorption efficiency was attributed to its large specific surface area, which enabled it to massively bind cationic dyes through electrostatic interaction, and a nanoporous structure that promoted intra-pore diffusion. Remarkably, the Cu-MOG displayed size-selective adsorption, based on adsorption studies concerning dyes of different sizes as calculated by density functional theory. Additionally, the adsorption performance of the Cu-MOG still maintained removal efficiency of 100% after three regeneration cycles. These results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater.

18.
Biomark Med ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31789049

RESUMO

Aim: This study aimed to investigate the correlation between the expression of circulating miR-208b and miR-499 and acute coronary syndrome (ACS) patients. Materials & methods: A total of 160 consecutive patients with ACS and 48 healthy control subjects were enrolled for primary analysis. The ACS patients (n = 160) were followed up for 6 months for further analysis regarding major adverse cardiac events. Results: Area under the curve values of miR-208b and miR-499 for predicting ACS were 0.910 and 0.851 (p < 0.001, respectively). Cox proportional hazards regression analysis revealed that miR-208b but not miR-499 was an independent predictor of major adverse cardiac events. Conclusion: Circulating miR-208b and miR-499 could be considered as diagnostic or prognostic biomarkers for patients with ACS.

19.
Mol Med Rep ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31789423

RESUMO

The present study aimed to explore the role of fibroblast growth factor 2 (FGF2) in the development and prognosis of gastric cancer (GC). The relationship between FGF2 mRNA expression levels and the clinical characteristics of GC was investigated using microarray data from four GC cohorts involving 726 patients obtained from the Gene Expression Omnibus. The results of the present study indicated that FGF2 expression levels were an independent factor affecting the prognosis of GC. The primary functions of FGF2 were related to cell adhesion and angiogenesis, and patients with high levels of FGF2 expression had poorer TNM staging and prognosis; these differences were statistically significant. In terms of immune infiltration, a higher extent of M2 macrophage intrusion was observed in patients with higher levels of FGF2. However, the degree of infiltration by dendritic and CD4+ T cells was lower, and this difference was statistically significant. Multivariate Cox proportional hazards model analysis revealed that age, TNM staging and FGF2 expression levels were independent prognostic factors for GC. In summary, FGF2 expression was demonstrated to be an independent prognostic factor in GC, and higher levels of FGF2 may promote the progression of this malignancy.

20.
ISA Trans ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31784047

RESUMO

Extreme learning machine is a popular machine learning technique for single hidden layer feed-forward neural network. However, due to the assumption of equal misclassification cost, the conventional extreme learning machine fails to properly learn the characteristics of the data with skewed category distribution. In this paper, to enhance the representation of few-shot cases, we break down that assumption by assigning penalty factors to different classes, and minimizing the cumulative classification cost. To this end, a case-weighting extreme learning machine is developed on a sparse cost matrix with a diagonal form. To be more actionable, we formulate a multi-objective optimization with respect to penalty factors, and optimize this problem using an evolutionary algorithm combined with an error bound model. By doing so, this proposed method is developed into an adaptive cost-sensitive learning, which is guided by the relation between the generalization ability and the case-weighting factors. In a broad experimental study, our method achieves competitive results on benchmark and real-world datasets for software bug reports identification.

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