[The method of determination for butyronitrile and isobutyronitrile in the air of workplace by dissolved desorption-gas chromatography].

Objective: To establish a method for the determination of butyronitrile and isobutyronitrile in the air of workplace by gas chromatography. Methods: In March 2020, butyronitrile and isobutyronitrile in the air of workplace was collected by silica gel, eluted with methanol, separated and determined by gas chromatogram with flame ionization detector, the characteristics of determination of nitrile and isobutyronitrile by gas chromatography were analyzed. Results: The limit of detection for butyronitrile and isobutyronitrile was 0.33 µg/ml. The linear range of butyronitrile determined by this method was 1.60-1600.00 µg/ml, y=2.295x-3.480, and the coefficient correlation was 0.99998, and the minimum detection concentration was 0.22 mg/m(3) (collected sample volume was 1.50 L) . The within-run precisions were 2.43%-4.12%, the between-run precisions were 1.72%-3.70%, and the desorption rates were 93.26%-98.41%. The linear range of isobutyronitrile determined by this method was 1.52-1520.00 µg/ml, y=2.208x-0.102, and the coefficient correlation was 0.99998, and the minimum detection concentration was 0.22 mg/m(3) (collected sample volume was 1.50 L) . The within-run precisions were 2.52%-3.22%, the between-run precisions were 1.20%-3.82%, and the desorption rates were 96.85%-102.50%. The sealed samples could be stored at least 10 days at room temperature without significant loss. Conclusion: The method has the advantages of good precision, high sensitivity and simple operation. It is suitable for the simultaneous determination of butyronitrile and isobutyronitrile in the air of workplace.

[Determination of acetylacetone in workplace air by solvent desorption-gas chromatography].

Objective: To establish a method for the determination of acetylacetone in the air of workplace by gas chromatography. Methods: In August 2020, acetylacetone in the air of workplace was collected by silica gel tube, eluted with methanol, separated and detected by gas chromatography with flame ionization detector. The detection limit and precision of the method were also analyzed. Results: The linear range of acetylacetone was 1.95-1950.60 µg/ml with the regression equation of y=0.815x-3.667, and the correlation coefficient was 0.99993. The limit of detection of the method was 0.18 µg/ml and the minimum detection concentration was 0.12 mg/m(3) (collected sample volume was 1.50 L). The within-run precisions were 1.08%-4.11% and the between-run precisions were 1.98%-2.80%. The desorption rates were 99.68%-100.45%. The sealed samples could be kept at least 15 days at room temperature without significant loss. Conclusion: The solvent desorption-gas chromatography method for the determination of acetylacetone has good precision, high sensitivity and simple operation, and is suitable for the determination of acetylacetone in the air of the workplace.

[The combination of YAP/TAZ predicts the clinical prognosis in patients with cholangiocarcinoma after radical resection].

Objective: Cholangiocarcinoma (CCA) is a malignant tumor derived from bile duct epithelial cells with extremely poor prognosis. The Hippo-Yes-associated protein (YAP)/transcription activator with PDZ binding motif (TAZ) signaling plays a critical role in cancer stem cell biology. Previous studies have shown that the positive expression of YAP/TAZ in CCA predicts larger tumor size and unfavorable clinical outcomes. We aim to evaluate the prognostic value of YAP/TAZ detection in CCA patients. Methods: CCA patients who underwent radical resection were retrospectively analyzed at our institution from January 2011 to June 2016. Postoperative pathological specimens were scored by YAP/TAZ immunohistochemical staining. The prognostic value of YAP/TAZ was analyzed by multivariate Cox-proportional hazards model. Results: A total of 91 CCA patients were enrolled. During a median follow-up time of 11.0 months, 69.2% patients relapsed and 45.1% died. The median OS and DFS were 10.7 months and 8.8 months respectively. The YAP/TAZ dual positive patients owned a worse TNM stage (P=0.015), poorer tissue differentiation (P=0.007), and a higher CA199 than those in negative patients. Multivariate Cox analysis identified that YAP/TAZ dual positivity as a significant factor predicted poorer OS (P=0.010) and DFS (P=0.028) in CCA patients after radical resection. In subgroup analysis, YAP/TAZ combination also significantly predicted OS (P=0.044) and DFS (P=0.043) in CCA patients with positive lymphatic metastasis and/or surgical margin who required adjuvant therapy. Conclusions: YAP/TAZ positivity is an independent predictive factor for survival in CCA patients after radical resectiony.

[Determination of thallium in the urine with colloidal palladium as the matrix modifier by graphite furnace atomic absorption Spectrometry].

Objective: To instruct a method of determining thallium in the urine by graphite furnace atomic absorption spectrometry(GF-AAS) with colloidal palladium as the matrix modifier. Methods: Urine samples were first diluted and then determined by GF-AAS with colloidal palladium while using thermal sample injection. Results: The optimum volume of colloidal palladium was 6 µl and the best ashing temperature was 600-800 ℃ while the atomization temperature was 1700-1900 ℃ . This method showed a good linearity relationship when the concentration between 0.33 and 50.0 µg/L while the correlation coefficient of standard curve line was 0.9992, and the detection limit was 0.33 µg/L and the recovery rate was between 92.7% and 102.3% with the intra-day precision in the range of 2.55% to 3.66% and the inter-day precision in the range of 1.77% to 3.85%. Conclusion: This method has the advantages of low detect limit, high sensitivity and good precision, and it can be used in the biological monitoring and emergency detecting of workers exposed to thallium.

[Related factors analysis for lymph node metastasis in papillary thyroid carcinoma: a series of 2 073 patients].

Objective: To investigate the related factors for lymph node metastasis (LNM), especially for high volume LNM (>5 metastatic lymph nodes) in papillary thyroid carcinoma (PTC). Methods: The medical records of 2 073 consecutive PTC patients who underwent lobectomy, near-total thyroidectomy or total thyroidectomy with ipsilateral or bilateral central lymph node dissection in Department of General Surgery, Peking Union Medical College Hospital from November 2013 to October 2014 were reviewed. Clinical and pathological features were collected. Univariate and multivariate analysis were performed to identify the related factors for LNM/high volume LNM. Results: In all 2 073 patients, LNM and high volume LNM were confirmed in 936 (45.15%) cases and 254 (12.25%) cases respectively. In univariate analysis, large tumor size, young patients (<40 years), male were associated with both LNM and high volume LNM. In multivariate analysis, tumor size >2.0 cm, young patients (<40 years), male were independent related factors of LNM (OR=5.262, 95% CI: 3.468 to 7.986; OR=2.447, 95% CI: 2.000 to 2.995; OR=1.988, 95% CI: 1.593 to 2.480, respectively, all P=0.000) and high volume LNM (OR=6.687, 95% CI: 4.477 to 9.986; OR=2.975, 95% CI: 2.224 to 3.980; OR=2.354, 95% CI: 1.737 to 3.191, respectively, all P=0.000). In 1 414 PTMC patients, a similar result was also demonstrated.Compared with young patients (<40 years), old patients (≥60 years) had lower incidence of LNM (25.47% vs. 52.24%, χ(2)=62.903, P=0.000) and high volume LNM (1.89% vs. 13.18%, χ(2)=37.341, P=0.000). Additionally, old patients also had lower risk of both LNM (OR=0.316, 95% CI: 0.194 to 0.517, P=0.000) and high volume LNM (OR=0.142, 95% CI: 0.034 to 0.599, P=0.000). Conclusions: The tumor size was the main related factor for both LNM and high volume LNM in PTC. The treatment should be more active in patients with tumor size >2 cm with consideration of higher incidence and risk for LNM and high volume LNM. Young patient was another important related factor for LNM and high volume LNM. In PTMC, old patients had lower incidence and risk for both LNM and high volume LNM. Dynamic observation or less surgical extent could be an option for these patients.

[Spatial distribution of occupational disease prevalence in Guangzhou and Foshan city by geographic information system].

Objective: To explore the occupational disease spatial distribution characteristics in Guangzhou and Foshan city in 2006-2013 with Geographic Information System and to provide evidence for making control strategy. Methods: The data on occupational disease diagnosis in Guangzhou and Foshan city from 2006 through 2013 were collected and linked to the digital map at administrative county level with Arc GIS12.0 software for spatial analysis. Results: The maps of occupational disease and Moran's spatial autocor-relation analysis showed that the spatial aggregation existed in Shunde and Nanhai region with Moran's index 1.727, -0.003. Local Moran's I spatial autocorrelation analysis pointed out the "positive high incidence re-gion" and the "negative high incidence region" during 2006~2013. Trend analysis showed that the diagnosis case increased slightly then declined from west to east, increase obviously from north to south, declined from? southwest to northeast, high in the middle and low on both sides in northwest-southeast direction. Conclusions: The occupational disease is obviously geographical distribution in Guangzhou and Foshan city. The corresponding prevention measures should be made according to the geographical distribution.

ICE1 demethylation drives the range expansion of a plant invader through cold tolerance divergence.

Cold tolerance adaption is a crucial determinant for the establishment and expansion of invasive alien plants into new cold environments; however, its evolutionary mechanism is poorly understood. Crofton weed (Ageratina adenophora), a highly invasive alien plant, is continuously spreading across subtropical areas in China, north-eastward from the first colonized south-western tropical regions, through cold tolerance evolution. Close relations between the cold tolerance levels of 34 populations, represented by 147 accessions, and the latitude, extreme lowest temperature, coldest month average temperature, and invasion period have provided direct insight into its cold tolerance divergence. A comparative study of the CBF pathway, associated with the cold tolerance enhancement of cold-susceptible CBF1-transgenic plant, among four geographically distinct crofton weed populations revealed that the CBF pathway plays a key role in the observed cold tolerance divergence. Four epialleles of the cold response regulator ICE1 ranged from 66 to 50 methylated cytosines, representing a 4.4% to 3.3% methylation rate and significantly corresponding to the lowest to highest cold tolerance levels among these different populations. The significant negative relation between the transcription levels of the primary CBF pathway members, except for CBF2, and the methylation levels among the four populations firstly demonstrates that the demethylation-upregulated transcription level of CBF pathway is responsible for this evolution. These facts, combined with the cold tolerance variation and methylation found among three native and two other introduced populations, indicate that the ICE1-demethylated upregulation of cold tolerance may be the underlying evolutionary mechanism allowing crofton weed to expand northward in China.

Postradiation Dermatofibrosarcoma Protuberans: Case Report and Literature Review.

Radiotherapy has long been known to induce soft tissue sarcomas. However, there are only six cases of post-radiation dermatofibrosarcoma protuberans (DFSP) reported in the literature, and no case in Asians has been reported so far. Herein, we report a case of DFSP, confirmed by immunohistochemistry, which developed on the old scar at the irradiated right chest wall of an Asian woman. We performed a radical surgical excision of the lesion and covered the defect with latissimus dorsi island myocutaneous flap followed the surgical treatment. 12 months postoperatively, the patient leads a good result without signs of recurrence.

Postradiation dermatofibrosarcoma protuberans : case report and literature review.

Radiotherapy has long been known to induce soft tissue sarcomas. However, there are only six cases of postradiation dermatofibrosarcoma protuberans (DFSP) reported in the literature, and no case in Asians has been reported so far. Herein, we report a case of DFSP, confirmed by immunohistochemistry, which developed on the old scar at the irradiated right chest wall of an Asian woman. We performed a radical surgical excision of the lesion and covered the defect with latissimus dorsi island myocutaneous flap followed the surgical treatment. 12 months postoperatively, the patient leads a good result without signs of recurrence.

Scaling of the low-energy structure in above-threshold ionization in the tunneling regime: theory and experiment.

A calculation of the second-order (rescattering) term in the S-matrix expansion of above-threshold ionization is presented for the case when the binding potential is the unscreened Coulomb potential. Technical problems related to the divergence of the Coulomb scattering amplitude are avoided in the theory by considering the depletion of the atomic ground state due to the applied laser field, which is well defined and does not require the introduction of a screening constant. We focus on the low-energy structure, which was observed in recent experiments with a midinfrared wavelength laser field. Both the spectra and, in particular, the observed scaling versus the Keldysh parameter and the ponderomotive energy are reproduced. The theory provides evidence that the origin of the structure lies in the long-range Coulomb interaction.

Effects of effective antithyroid therapy on adiposity and skeletal muscle in patients with hyperthyroidism across gender and age groups.

OBJECTIVE: The study aimed to evaluate the effects of effective antithyroid therapy on adiposity and skeletal muscle in patients with hyperthyroidism across gender and age groups. PATIENTS AND METHODS: A total of 57 adult hyperthyroid patients (21 males and 36 females) who underwent effective antithyroid medication from January 2018 to January 2021 at Liuzhou People's Hospital and the First Affiliated Hospital of Guangxi Medical University were recruited and followed up for one year to observe the long-term efficacy of the antithyroid therapy. The eligible patients were divided by age and gender groups into male group A (males of <40 years old, n=12), female group A (females of <40 years old, n=19), male group B (males of 40-59 years old, n=8), female group B (female of 40-59 years old, n=13), and group C (patients of ≥60 years old, including one male and four females). A cohort of 57 healthy individuals was also recruited as controls. A Dual Energy X-ray (DXA) was performed to measure changes in fat and lean tissue mass and grip strength of the dominant hand before and after treatment and the body fat percentage (BFP). The whole-body skeletal muscle mass index (ASMI) was calculated to evaluate the long-term effects of antithyroid therapy. RESULTS: The eligible patients of all ages reported significantly increased total fat mass, body fat percentage, and body mass index (p<0.05). The total lean tissue mass was markedly increased in male and female group A (p<0.05), showed no significant changes in male and female group B (p>0.05), and exhibited a marked decline in group C (p<0.05). Significantly elevated ASMI after treatment was observed in male and female group A (p<0.05), while no significant changes were detected in ASMI after treatment in groups B and C (p>0.05). All patients in groups A and B exhibited enhanced grip strength, while the enhancement of grip strength in patients of group C was poor (p>0.05). CONCLUSIONS: Effective anti-hyperthyroidism therapy improves fat mass and body fat percentage in patients of all ages. However, gender and age differences exist in the effectiveness of improvements in total muscle mass and ASMI. Suboptimal muscle mass recovery was reported in patients over 40 years after effective anti-hyperthyroid therapy.

Experimental and DFT study of thiol-stabilized Pt/CNTs catalysts.

Using a combination of experiments and density functional theory (DFT) calculations, we explored the mechanisms of the stabilization effect of the thiolized (-SH) group on the Pt/SH-CNTs catalyst. Pt particles supported on the hydroxyl functionalized CNTs (Pt/OH-CNTs) are synthesized as a baseline for comparison. Experimentally, the platinum on OH-CNTs has a stronger tendency for aggregation than that on SH-CNTs. The differences in the oxidation resistance, migration activation energy, and corrosion resistance between the Pt/SH-CNTs and Pt/OH-CNTs are calculated using DFT. The DFT calculations indicate that the -SH group enhances the oxidation resistance of the Pt cluster and CNTs and restricts Pt migration on the CNTs. DFT calculations also suggest that the enhanced stability of Pt/SH-CNTs originates from the increased interaction between Pt and SH-CNTs and the depressed d-band center of the Pt NPs. Thus, the functional groups on the CNTs used for stabilization of supported Pt NPs should provide a deposit and anchor site for Pt NPs and maintain the perfect structure of CNTs rather than destroying it.

Allelic origin of the abnormal prion protein isoform in familial prion diseases.

The hallmark of prion diseases is the presence of an aberrant isoform of the prion protein (PrP(res)) that is insoluble in nondenaturing detergents and resistant to proteases. We investigated the allelic origin of PrP(res) in brains of subjects heterozygous for the D178N mutation linked to fatal familial insomnia (FFI) and a subtype of Creutzfeldt-Jakob disease (CJD178), as well as for insertional mutations associated with another CJD subtype. We found that in FFI and CJD178 subjects, only mutant PrP was detergent-insoluble and protease-resistant. Therefore, PrP(res) derives exclusively from the mutant allele carrying the D178N mutation. In contrast, in the CJD subtype harboring insertional mutations, wild-type PrP was also detergent-insoluble and likely to be protease-resistant. Our findings indicate that the participation of the wild-type PrP in the formation of PrP(res) depends on the type of mutations, providing an insight into the molecular mechanisms underlying the phenotypic heterogeneity in familial prion diseases.

Tau gene mutation in familial progressive subcortical gliosis.

Familial forms of frontotemporal dementias are associated with mutations in the tau gene. A kindred affected by progressive subcortical gliosis (PSG), a rare form of presenile dementia, has genetic linkage to chromosome 17q21-22. This kindred (PSG-1) is included in the 'frontotemporal dementias and Parkinsonism linked to chromosome 17' group along with kindreds affected by apparently different forms of atypical dementias. Some of these kindreds have mutations in the tau gene. We report here that PSG-1 has a tau mutation at position +16 of the intron after exon 10. The mutation destabilizes a predicted stem-loop structure and leads to an over-representation of the soluble four-repeat tau isoforms, which assemble into wide, twisted, ribbon-like filaments and ultimately result in abundant neuronal and glial tau pathology. The mutations associated with PSG and other atypical dementias can be subdivided into three groups according to their tau gene locations and effects on tau. The existence of tau mutations with distinct pathogenetic mechanisms may explain the phenotypic heterogeneity of atypical dementias that previously led to their classification into separate disease entities.

LncRNA CASC11 promotes the development of esophageal carcinoma by regulating KLF6.

OBJECTIVE: The aim of this study was to investigate the expression level of long non-coding RNA (lncRNA) CASC11 in esophageal carcinoma (ECa), and to further explore its relationship with clinical progression, pathological parameters, and prognosis of ECa patients. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine the level of lncRNA CASC11 in 45 pairs of ECa tissues and adjacent normal tissues. The relationship between the lncRNA CASC11 level and clinical progression, pathological parameters, and prognosis of ECa patients was analyzed. Meanwhile, the level of lncRNA CASC11 in the ECa cell lines was verified by qPCR as well. In addition, lncRNA CASC11 knockdown model was constructed using lentiviral transfection in ECa cell lines. Subsequently, the cell counting kit-8 (CCK8), colony formation assay, and flow cytometry were used to explore the effect of lncRNA CASC11 on the biological functions of the ECa cells. Finally, the Western Blot and the recovery experiments were used to explore the potential mechanism. RESULTS: In this work, the qPCR results showed that the expression level of lncRNA CASC11 in the ECa tissues was remarkably higher than that of the adjacent normal tissues, and the difference was statistically significant (p<0.05). Compared with patients with a low level of lncRNA CASC11, the pathological stage of patients with high expression was significantly higher, while the overall survival rate was lower (p<0.05). Compared with negative control (NC) group, the proliferation ability of the cells in the lncRNA CASC11 knockdown group CASC11 significantly decreased, whereas cell apoptosis remarkably increased (p<0.05). The Western Blot results revealed that protein expression of KLF6 was remarkably up-regulated after lncRNA CASC11 knockdown. In addition, the recovery experiments found that lncRNA CASC11 and KLF6 had mutual regulation, thereby promoting the malignant progression of ECa. CONCLUSIONS: LncRNA CASC11 expression was remarkably up-regulated in ECa, which was associated with the pathological stage and poor prognosis of ECa. In addition, lncRNA CASC11 could promote the malignant progression of ECa by mutual regulation of KLF6.

Semi-nested PCR detection of Babesia orientalis in its natural hosts Rhipicephalus haemaphysaloides and buffalo.

Babesiosis has recently been recognized as an emerging infectious disease of buffalo in China. In order to investigate the epidemiology and enzootic potential of this parasite in Hubei province, we sought to develop a semi-nested PCR to detect Babesia orientalis in buffalo and the potential tick vector-Rhipicephalus haemaphysaloides by amplifying a specific 257bp fragment of B. orientalis 18S rRNA gene. The practical limit of detection showed that it had high sensitivity and an approximate parasitemia of 0.00000012% was detected by the PCR system. The blood samples of 121 asymptomatic buffaloes collected from four babesia endemic counties and that of 71 asymptomatic buffaloes collected from three babesia free counties in Hubei province of China were examined for the presence of B. orientalis using both Wright-Giemsa stained blood smear and semi-nested PCR. Microscopic examination revealed that 5/121 animals were positive, whereas 24/121 animals were positive by the semi-nested PCR assay. Of 378 ticks (R. haemaphysaloides) collected from buffaloes and examined by the semi-nested PCR, 35 were positive. The results showed that the semi-nested PCR was a useful method to investigate the epidemiology of buffalo babesiosis (B. orientalis), which is widely distributed in Hubei province, China.

Clinicopathological features, post-surgical survival and prognostic indicators of elderly patients with hepatocellular carcinoma.

AIM: Comprehensive data regarding elderly patients with hepatocellular carcinoma (HCC) were limited. The present study aims to widen the knowledge based on patients in China. METHODS: Fifty-four elderly (> or =65 years) and 125 non-elderly HCC patients undergoing hepatectomy were enrolled in this retrospective study. Clinicopathological features and post-surgical survival were compared between two groups. Prognostic indicators of elderly patients were defined by uni- and multivariate analyses. RESULTS: Contrast to non-elderly patients, the elderly presented significantly lower rates of HBsAg positivity, Child-Pugh grade A, alpha-fetoprotein (AFP) marked elevation, portal vein tumour thrombosis (PVTT), satellite nodule, and intrahepatic recurrence, smaller tumour sizes, earlier TNM staging and better histological differentiation. No significant differences were found in perioperative mortality rate and post-surgical survival between two groups. PVTT and Edmondson-Steiner grading were identified as independent prognostic indicators of both overall and disease-free survival by multivariate analysis, whereas Child-Pugh grading independently affected the overall survival. CONCLUSIONS: HCC in the elderly seemed to be less HBV-associated, less progressive and less aggressive than that in the non-elderly. Hepatectomy for the elderly could make a satisfactory prognosis and be well tolerated. Some tumour-related factors independently predict the prognosis of elderly HCC patients, and their liver function status should be further valued.

Molecular adjustment of the electronic properties of nanoporous electrodes in dye-sensitized solar cells.

Molecular modification of dye-sensitized, mesoporous TiO2 electrodes changes their electronic properties. We show that the open-circuit voltage (V(oc)) of dye-sensitized solar cells varies linearly with the dipole moment of coadsorbed phosphonic, benzoic, and dicarboxylic acid derivatives. A similar dependence is observed for the short-circuit current density (I(sc)). Photovoltage spectroscopy measurements show a shift of the signal onset as a function of dipole moment. We explain the dipole dependence of the V(oc) in terms of a TiO2 conduction band shift with respect to the redox potential of the electrolyte, which is partially followed by the energy level of the dye. The I(sc) shift is explained by a dipole-dependent driving force for the electron current and a dipole-dependent recombination current.

Unification of catalytic oxygen reduction and hydrogen evolution reactions: highly dispersive Co nanoparticles encapsulated inside Co and nitrogen co-doped carbon.

The Co nanoparticles encapsulated inside Co and nitrogen co-doped carbon catalysts with small particle size and homogenous distribution of Co NPs were elaborately synthesized, which exhibit evidently outstanding activity and stability toward ORR/HER.