Protein expression patterns and metal metabolites in a protogynous hermaphrodite fish, the ricefield eel (Monopterus albus).

BACKGROUND: The ricefield eel Monopterus albus undergoes a natural sex change from female to male during its life cycle, and previous studies have shown the potential mechanisms of this transition at the transcriptional and protein levels. However, the changes in protein levels have not been fully explored, especially in the intersexual stage. RESULTS: In the present study, the protein expression patterns in the gonadal tissues from five different periods, the ovary (OV), early intersexual stage gonad (IE), middle intersexual stage gonad (IM), late intersexual stage gonad (IL), and testis (TE), were determined by untargeted proteomics sequencing. A total of 5125 proteins and 394 differentially expressed proteins (DEPs) were detected in the gonadal tissues. Of the 394 DEPs, there were 136 between the OV and IE groups, 20 between the IM and IE groups, 179 between the IL and IM groups, and 59 between the TE and IL groups. Three candidate proteins, insulin-like growth factor 2 mRNA-binding protein 3 isoform X1 (Igf2bp3), triosephosphate isomerase (Tpi), and Cu-Zn superoxide dismutase isoform X1 [(Cu-Zn) Sod1], were validated by western blotting to verify the reliability of the data. Furthermore, metal metabolite-related proteins were enriched in the IL vs. IM groups and TE vs. IL groups, which had close relationships with sex change, including Cu2+-, Ca2+-, Zn2+- and Fe2+/Fe3+-related proteins. Analysis of the combined transcriptome data revealed consistent protein/mRNA expression trends for two metal metabolite-related proteins/genes [LOC109953912 and calcium Binding Protein 39 Like (cab39l)]. Notably, we detected significantly higher levels of Cu2+ during the sex change process, suggesting that Cu2+ is a male-related metal metabolite that may have an important function in male reproductive development. CONCLUSIONS: In summary, we analyzed the protein profiles of ricefield eel gonadal tissues in five sexual stages (OV, IE, IM, IL, and TE) and verified the plausibility of the data. After preforming the functional enrichment of metal metabolite-related DEPs, we detected the contents of the metal metabolites Zn2+, Cu2+, Ca2+, and Fe2+/Fe3+ at these five stages and screened for (Cu-Zn) Sod1 and Mmp-9 as possible key proteins in the sex reversal process.

Population structure and adaptability analysis of Schizothorax o'connori based on whole-genome resequencing.

BACKGROUND: Schizothorax o'connori is an endemic fish distributed in the upper and lower reaches of the Yarlung Zangbo River in China. It has experienced a fourth round of whole gene replication events and is a good model for exploring the genetic differentiation and environmental adaptability of fish in the Qinghai-Tibet Plateau. The uplift of the Qinghai-Tibet Plateau has led to changes in the river system, thereby affecting gene exchange and population differentiation between fish populations. With the release of fish whole genome data, whole genome resequencing has been widely used in genetic evolutionary analysis and screening of selected genes in fish, which can better elucidate the genetic basis and molecular environmental adaptation mechanisms of fish. Therefore, our purpose of this study was to understand the population structure and adaptive characteristics of S. o'connori using the whole-genome resequencing method. RESULTS: The results showed that 23,602,746 SNPs were identified from seven populations, mostly distributed on chromosomes 2 and 23. There was no significant genetic differentiation between the populations, and the genetic diversity was relatively low. However, the Zangga population could be separated from the Bomi, Linzhi, and Milin populations in the cluster analysis. Based on historical dynamics analysis of the population, the size of the ancestral population of S. o'connori was affected by the late accelerated uplift of the Qinghai Tibet Plateau and the Fourth Glacial Age. The selected sites were mostly enriched in pathways related to DNA repair and energy metabolism. CONCLUSION: Overall, the whole-genome resequencing analysis provides valuable insights into the population structure and adaptive characteristics of S. o'connori. There was no obvious genetic differentiation at the genome level between the S. o'connori populations upstream and downstream of the Yarlung Zangbo River. The current distribution pattern and genetic diversity are influenced by the late accelerated uplift of the Qinghai Tibet Plateau and the Fourth Ice Age. The selected sites of S. o'connori are enriched in the energy metabolism and DNA repair pathways to adapt to the low temperature and strong ultraviolet radiation environment at high altitude.

FoxH1 Represses the Promoter Activity of cyp19a1a in the Ricefield Eel (Monopterus albus).

Forkhead box H1 (FoxH1) is a sexually dimorphic gene in Oreochromis niloticus, Oplegnathus fasciatus, and Acanthopagrus latus, indicating that it is essential for gonadal development. In the present study, the molecular characteristics and potential function of FoxH1 and the activation of the cyp19a1a promoter in vitro were evaluated in Monopterus albus. The levels of foxh1 in the ovaries were three times higher than those in the testes and were regulated by gonadotropins (Follicle-Stimulating Hormone and Human Chorionic Gonadotropin). FoxH1 colocalized with Cyp19a1a in the oocytes and granulosa cells of middle and late vitellogenic follicles. In addition, three FoxH1 binding sites were identified in the proximal promoter of cyp19a1a, namely, FH1 (-871/-860), FH2 (-535/-524), and FH3 (-218/-207). FoxH1 overexpression significantly attenuated the activity of the cyp19a1a promoter in CHO cells, and FH1/2 mutation increased promoter activity. Taken together, these results suggest that FoxH1 may act as an important regulator in the ovarian development of M. albus by repressing cyp19a1a promoter activity, which provides a foundation for the study of FoxH1 function in bony fish reproductive processes.

Differentially expressed immune-related genes in hemocytes of the pearl oyster Pinctada fucata against allograft identified by transcriptome analysis.

The pearl oyster Pinctada fucata is commonly cultured for marine pearls in China. To culture pearls, a mantle piece from a donor pearl oyster is grafted with a nucleus into a receptor. This transplanted mantle piece may be rejected by the immune system of the recipient oyster, thus reducing the success of transplantation. However, there have been limited studies about the oyster's immune defense against allograft. In this study, hemocyte transcriptome analysis was performed to detect the immune responses to allograft in P. fucata at 0 h and 48 h after a transplant. The sequencing reaction produced 92.5 million reads that were mapped against the reference genome sequences of P. fucata. The Gene Ontology (GO) annotation and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to identify all immune-related differentially expressed genes (DEGs). Compared with patterns at 0 h, a total of 798 DEGs were identified, including 410 up-regulated and 388 down-regulated genes at 48 h. The expression levels of interleukin receptor and toll-like receptor in hemocytes were increased significantly 48 h post-transplant, indicating that the oyster immune response was induced. Finally, altered levels of 18 randomly selected immune-related DEGs were confirmed by quantitative real-time PCR (qRT-PCR). Our results provide the basis for further analysis of the immune rejection of allotransplantation.

[Prognostic analysis of cervical lymph node metastasis in patients with thoracic esophageal squamous cell carcinoma].

OBJECTIVE: To analyze the prognostic factors of cervical lymph node metastasis (CLN) in thoracic esophageal squamous cell carcinoma (TESCC), and to probe and verify the esophageal carcinoma staging of the 7th edition of American Joint Committee on Cancer (AJCC) TNM staging system. METHODS: A total of 1 715 TESCC patients underwent radical esophagectomy plus three-field lymph node dissection at Fujian Provincial Cancer Hospital between January 1993 and March 2007. 547 patients had pathological metastasis of CLN, and 296 patients received surgery only (S group) and 251 patients received postoperative radiotherapy (S+R group). The prognostic factors were analyzed and the pattern of recurrence and metastases was studied according to the esophageal carcinoma staging criteria of the 7th edition of AJCC TNM staging system. RESULTS: The metastasis rate of CLN was 31.9% for the entire group, 44.2%, 31.5% and 14.4% for the upper, middle and lower TESCC, respectively (P < 0.001). The 5-year overall survival rate of the patients with metastatic CLN was 27.7%, and the median overall survival time was 27.5 months. The 5-year survival rate was 21.3% in the S group and 34.2% in the S+R group, and the median survival time was 21.9 months in the S group and 35.4 months in the S+R group (P < 0.001). Multivariate analysis showed that gender, lesion length in X-ray, N stage, AJCC stage and treatment modality were independent prognostic factors of CLN metastasis in TESCC. Independent prognostic factors for S group included the primary tumor site, pT stage, N stage and AJCC stage, and N stage was an independent prognostic factor for the S+R group. CONCLUSIONS: TESCC with CLN metastasis have a better prognosis after surgery. It supports that cervical lymph nodes belong to regional lymph nodes classified in the 7th edition of AJCC TNM staging system.

[Value of postoperative radiochemotherapy for thoracic esophageal squamous cell carcinoma with lymph node metastasis].

OBJECTIVE: To retrospectively compare the efficacy of postoperative radiotherapy (RT) alone with that of postoperative radiotherapy with concurrent chemotherapy (CRT) for thoracic esophageal squamous cell carcinoma (EPC) with positive lymph nodes, and to evaluate the clinical value of RT + CRT. METHODS: 304 EPC patients underwent esophagectomy with three-field lymph node dissection had pathological lymph node metastases, but no hematogenous distant metastasis. Among them, 140 cases underwent postoperative RT alone, and 164 cases underwent postoperative CRT. The dose of irradiation was 50 Gy, and the chemotherapy regimen was taxol and cis-platinum, and a cycle was 21 days. RESULTS: The 1-, 3- and 5-year total survival rates of the whole group were 90.1%, 56.6% and 43.3%, respectively, with a median survival time of 49.7 months. The 5-year overall survival rates of the CRT and RT groups were 47.4% and 38.6%, respectively (P = 0.030), with a median survival time of 53.5 and 41.7 months, respectively (P = 0.030). The overall survival rates of the patients who underwent 1, 2, 3, 4 cycles of chemotherapy were 24.4%, 53.0%, 58.1% and 43.3%, respectively (P = 0.007). Among them, the 5-year total survival rate of patients with 2-4 cycles of chemotherapy was significantly better than that of patients who underwent one cycle of chemotherapy (P = 0.001). Univariate analysis showed that number of metastatic lymph nodes, pT stage, therapeutic regimen and number of chemotherapy cycles were significantly correlated with the prognosis of the patients (P < 0.05 for all). Multivariate analysis showed that number of metastatic lymph nodes, pT stage, and number of chemotherapy cycles were independent prognostic factors of the patients (P < 0.05 for all). Early toxic effects including neutropenia, radiation esophagitis, and gastrointestinal effects were significantly more severe in the CRT group than that in the RT group (P < 0.05), however, there were no significant differences of late toxic effects between the two groups (P > 0.05). CONCLUSION: Postoperative CRT for thoracic EPC with positive lymph nodes can improve the survival rate, with tolerable adverse effects.

Sulfonated P-W modified nitrogen-containing carbon-based solid acid catalysts for one-pot conversion of cellulose to ethyl levulinate under water-ethanol medium.

Converting cellulose (Cel) into ethyl levulinate (EL) is one of the promising strategies for supplying liquid fuels. In this paper, the prepared sulfonated P-W-modified N-containing carbon-based solid acid catalyst (PWNCS), in which the Polyaniline (PANI) was employed as N and C precursors, successfully converted Cel into EL under the water-ethanol medium. The characterization results demonstrated that a tiny addition of P increased the Brønsted acid sites (BAS) content and defective WO3 provided the Lewis acid sites (LAS), meanwhile, the sulfonation process did not change the fundamental structure but introduced the sulfonic groups to dramatically increase the acidic content. Therefore, under optimized reaction conditions, PWNCS realized about 100% Cel conversion and 71.61% of EL yield, furthermore, the selectivity of EL reached 89.14%. In addition, the effect of water on the reaction pathway of Cel to EL over PWNCS was proposed. The addition of water generally resulted in the hydration of defective WO3 to reduce the LAS and increase BAS, which significantly inhibited the side reactions of retro-aldol condensation (RAC) and subsequent etherification reactions during Cel conversion and then improved the selectivity of EL.

Transcriptome analysis of the mantle tissue of Pinctada fucata with red and black shells under salinity stress.

To understand the molecular responses of Pinctada fucata with different shell colors to salinity stress, we used transcriptome sequencing on the mantle of P. fucata with a black shell and red shell color under the salinity of 20, 35, and 50. The 414 and 2371 differentially expressed genes (DEGs) in P. fucata with a black shell under low- or high-salt stress, while there were 588 and 3009 DEGs in P. fucata with a red shell. KEGG pathway enrichment analysis showed that, under low salt stress, the DEGs of P. fucata with the black shell were significantly enriched in pathways MAPK signaling pathway, protein processing in endoplasmic reticulum, vitamin B6 metabolism, longevity regulating pathway-multiple species, estrogen signaling pathway and antigen processing and presentation, the DEGs of P. fucata with a red shell were significantly enriched in pathways vitamin B6 metabolism. Under high salt stress, the DEGs of P. fucata with a red shell were significantly enriched in pathways arginine biosynthesis. 11 DEGs were randomly selected for quantitative real-time PCR, and the results were consistent with the RNA-seq. In addition, under high salt stress, DEGs were enriched into some pathways related to osmotic regulation and immune defense of P. fucata with black shell and red shell, such as Glycolysis / Gluconeogenesis, AMPK signaling pathway, Beta-Alanine metabolism, Glycine, serine and threonine metabolism, MAPK signaling pathway and Phagosome. The study showed that high salt stress had a greater influence on P. fucata with two shell colors, and P. fucata with a black shell made a positive immune defense response. Our results will improve to further understand the salt tolerance mechanism of P. fucata with different shell colors.

A macrophage migration inhibitory factor like oxidoreductase from pearl oyster Pinctada fucata involved in innate immune responses.

Macrophage migration inhibitory factor (MIF) is an important cytokine and plays a crucial role as a pivotal regulator of innate immunity. In this study, a MIF cDNA was identified and characterized from the pearl oyster Pinctada fucata (designated as PoMIF). The full-length of PoMIF was 1544 bp and consisted of a 5'-untranslated region (UTR) of 45 bp, a 3'-UTR of 1139 bp with a polyadenylation signal (AATAAA) at 12 nucleotides upstream of the poly (A) tail. The open reading frame (ORF) of PoMIF was 360 bp which encoded a polypeptide of 120 amino acids with an estimated molecular mass of 13.3 kDa and a predicted pI of 6.1. SMART analysis showed that PoMIF contained the catalytic-sites P² and K³³ for tautomerase activity, a motif C57GSV6° for oxidoreductase activity and a MIF family signature D55PCGSVEVYSIGALG69. Homology analysis revealed that the PoMIF shared 40.3-65.5% similarity and 26.9-45.0% identity to other known MIF sequences. PoMIF mRNA was constitutively expressed in seven selected tissues of healthy pearl oysters, with the highest expression level in digestive gland. Eight hours after P. fucata was injected with Vibrio alginolyticus, the expression of PoMIF mRNA was significantly up-regulated in digestive gland, gills, hemocytes and intestine. The cDNA fragment encoding mature protein of PoMIF was subcloned to expression vector pRSET and transformed into Escherichia coli BL21 (DE3). The recombinant PoMIF (rPoMIF) was expressed and purified under optimized conditions. Function analysis showed that rPoMIF had oxidoreductase activity and could utilize dithiothreitol (DTT) as reductant to reduce insulin.

Cardiac MRI segmentation with focal loss constrained deep residual networks.

Delineating anatomical structures for cardiac magnetic resonance imaging (CMRI) is crucial for various medical applications such as medical diagnoses, treatment, and pathological studies. CMRI segmentation, which aims to automatically and accurately segment the heart structures, is highly beneficial for cardiologists. However, it is non-trivial to perfectly segment the ventricles, especially for the heart apex slices, considering their small sizes compared to the input images. For example, the endocardium in the Sunnybrook dataset only occupies 4% of the entire image by average. During the training process, these target pixels, or other hard samples, are buried by the massive backgrounds that make the model mostly receive optimization signals from easy samples. In this paper, we propose a focal loss constrained residual network (FR-Net) to tackle the problem. In order to mitigate the fact that the gradients of the hard samples can be easily overwhelmed by the easy samples, we use a pixel-wise re-weighting strategy to balance the gradients. Furthermore, considering focal loss constraints for each pixel independently, we propose an alternative training fashion that trains the model with focal loss and dice loss alternatively. The segmentation model can not only benefit from the pixel-wise focal loss but also from the region-wise dice loss to comprehensively optimize the model. We conducted thorough experiments on the Sunnybrook dataset, CMRI dataset, right ventricle dataset, and ACDC dataset to verify the effectiveness of the proposed method.

Active site-dominated electromagnetic enhancement of surface-enhanced Raman spectroscopy (SERS) on a Cu triangle plate.

Revealing the sensitivity and selectivity of the Raman enhancement mechanism is extremely significant for disease diagnosis, environmental surveillance, and food safety supervision. In this study, chemical erosion copper triangle plates (CTPs) were employed as SERS substrate to detect the rhodamine B (Rh B) probe molecule at different etching times. A simple and cost-effective method affords unique insights into the surface enrichment of analytes, which could facilitate the high-performance SERS analysis of numerous analytes. The relationship between the Raman intensity and the concentration of Rh B follows the Freundlich model, which means that the wet-etching surface can create SERS-active site attachment Rh B molecules on the CTPs. The morphology of CTPs was modified by H2O2/HCl etchants; however, the composition of CTPs remained stable without oxidation. This proposes that the largest contribution to the enhancement was the hot-spots that can produce surface plasma resonance on the CTPs. The number of hot-spots can be intelligently adjusted by the artificial control of the surface morphology of metal materials, providing an unambiguous improvement in the SERS sensitivity and capability.

The kinetics model and pyrolysis behavior of the aqueous fraction of bio-oil.

The pyrolysis behavior and kinetics of the aqueous fraction of bio-oil were studied through thermogravimetric (TG) analysis. Based on the experimental data, activation energies and kinetic parameters were calculated by the Achar differential method and the Coats-Redfern integral method, then the most probable mechanism functions and kinetics model were obtained at last. The results show that the pyrolysis of bio-oil aqueous fraction can be divided into three stages, that is, the volatilization of volatile fractions, the decomposition stage of heavy fractions and char combustion. The experimental results show that the activation energy of volatilization is higher than that of the decomposition stage. The first stage was expressed as the first order reaction and the second stage the second order reaction. The correlation coefficient between the two stages illustrates that the reactions are in well conformity with each other and the calculated value of conversion is consistent with the experimental results.

Postoperative radiation therapy with or without concurrent chemotherapy for node-positive thoracic esophageal squamous cell carcinoma.

PURPOSE: To retrospectively compare the efficacy of radiation therapy (RT) and chemotherapy plus RT (CRT) for the postoperative treatment of node-positive thoracic esophageal squamous cell carcinoma (TESCC) and to determine the incidence and severity of toxic reactions. METHODS AND MATERIALS: We retrospectively reviewed data from 304 patients who had undergone esophagectomy with 3-field lymph node dissection for TESCC and were determined by postoperative pathology to have lymph node metastasis without distant hematogenous metastasis. Of these patients, 164 underwent postoperative chemotherapy (cisplatin 80 mg/m(2), average days 1-3, plus paclitaxel 135 mg/m(2), day 1; 21-day cycle) plus RT (50 Gy), and 140 underwent postoperative RT alone. RESULTS: The 5-year overall survival rates for the CRT and RT groups were 47.4% and 38.6%, respectively (P=.030). The distant metastasis rate, the mixed (regional lymph node and distant) metastasis rate, and the overall recurrence rate were significantly lower in the CRT group than in the RT group (P<.05). However, mild and severe early toxic reactions, including neutropenia, radiation esophagitis, and gastrointestinal reaction, were significantly more common in the CRT group than in the RT group (P<.05). No significant differences in incidence of late toxic reactions were found between the 2 groups. CONCLUSIONS: Our results show that in node-positive TESCC patients, postoperative CRT is significantly more effective than RT alone at increasing the overall survival and decreasing the rates of distant metastasis, mixed metastasis, and overall recurrence. Severe early toxic reactions were more common with CRT than with RT alone, but patients could tolerate CRT.

Number and location of positive nodes, postoperative radiotherapy, and survival after esophagectomy with three-field lymph node dissection for thoracic esophageal squamous cell carcinoma.

PURPOSE: To analyze influences of the number and location of positive lymph nodes and postoperative radiotherapy on survival for patients with thoracic esophageal squamous cell carcinoma (TE-SCC) treated with radical esophagectomy with three-field lymphadenectomy. METHODS AND MATERIALS: A total of 945 patients underwent radical esophagectomy plus three-field lymph node dissection for node-positive TE-SCC at Fujian Provincial Tumor Hospital between January 1993 and March 2007. Five hundred ninety patients received surgery only (S group), and 355 patients received surgery, followed 3 to 4 weeks later by postoperative radiotherapy (S+R group) to a median total dose of 50 Gy in 25 fractions. We assessed potential associations among patient-, tumor-, and treatment-related factors and overall survival. RESULTS: Five-year overall survival rates were 32.8% for the entire group, 29.6% for the S group, and 38.0% for the S+R group (p = 0.001 for S vs. S+R). Treatment with postoperative radiotherapy was particularly beneficial for patients with ≥3 positive nodes and for those with metastasis in the upper (supraclavicular and upper mediastinal) region or both the upper and lower (mediastinal and abdominal) regions (p < 0.05). Postoperative radiotherapy was also associated with lower recurrence rates in the supraclavicular and upper and middle mediastinal regions (p < 0.05). Sex, primary tumor length, number of positive nodes, pathological T category, and postoperative radiotherapy were all independent predictors of survival. CONCLUSIONS: Postoperative radiotherapy was associated with better survival for patients with node-positive TE-SCC, particularly those with three or more positive nodes and positive nodes in the supraclavicular and superior mediastinal regions.

Molecular characterization and mRNA expression of catalase from pearl oyster Pinctada fucata.

Catalase (EC 1.11.1.6) is an important antioxidant enzyme that protects aerobic organisms against oxidative damage by degrading hydrogen peroxide to water and oxygen. In the present study, a catalase cDNA of peal oyster Pincatada fucata (designated as PoCAT) is cloned and characterized by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) methods. PoCAT is 2428 bp long and consists of a 5'-UTR of 140 bp, an unusually long 3'-UTR of 749 bp, and an open reading frame (ORF) of 1539 bp. The ORF of PoCAT encodes a polypeptide of 512 amino acids with molecular weight of 58.1 kDa and the theoretical isoelectric point of 8.4. PoCAT shares 62.3-82.2% identity and 73.0-92.0% similarity to other catalase amino acid sequences. Sequence alignment indicates that PoCAT contains the proximal heme-ligand signature sequence (R³5¹LFSYSDT³58), the proximal active site signature (F6¹NRERIPERVVHAKGGGA78), and the three catalytic amino acid residues (His7², Asn¹45, and Tyr³55). PoCAT has two potential glycosylation sites (N4³6YS4³8 and N478FS48°) and a peroxisome targeting signal (ASL). PoCAT mRNA was ubiquitously expressed in all detected tissues, and the expression level of PoCAT mRNA was higher in intestine and mantle. The expression profile analysis showed that the expression level of PoCAT mRNA in intestine was significantly up-regulated at 2, 4 and 12 h after Vibrio alginolyticus stimulation. These results demonstrated that PoCAT is a typical member of catalase family and might be involved in innate immune responses of pearl oyster.

Postoperative radiotherapy improved survival of poor prognostic squamous cell carcinoma esophagus.

BACKGROUND: The purpose of this study was identify prognostic factors and to investigate the association between postoperative radiotherapy and overall survival of thoracic esophageal squamous cell carcinoma patients. METHODS: From January 1993 to March 2007, 1,715 patients underwent extended esophagectomy with three-field lymph node dissection with or without postoperative radiotherapy and were eligible for analysis. Patients were grouped to surgery only (n = 1,277) and surgery plus postoperative radiotherapy (n = 438). Radiation dose was 50 Gy in 25 fractions. RESULTS: The overall survival rates at 1, 3, 5, and 10 years were 86.6%, 61.3%, 49.4%, and 36.1%, respectively. Univariate and multivariate analyses showed that age 60 years or more, male sex, tumor more than 5 cm long, poorly differentiated histology, T4 tumor, presence of a vascular cancer thrombus in the surgical specimen, lymph node positivity, 3 or more positive lymph nodes, and disease stage II or higher were negative prognostic factors for overall survival. Postoperative radiation therapy improved overall survival for patients with poor disease-related prognostic factors: positive nodal disease, 3 or more positive lymph nodes, stage III/IV, and large or deeply invading tumor. Postoperative radiation had no survival benefit for patients who did not have the poor disease-related prognostic factors. CONCLUSIONS: Postoperative radiotherapy is indicated for patients with poor disease-related prognostic factors.