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As a novel environmental pollutant, the impacts of nanoplastics on crops have attracted more and more attention. To explore the response of soybean to polystyrene nanoplastics (PS-NPs) at physiological and gene expression levels, this experiment used hydroponics to determine the phenotype and physiological indexes of soybean seedlings after exposure to 50 mg/L 100 nm PS-NPs for 10 days, and carried out transcriptome sequencing analysis of soybean seedling root system. The results showed that the growth of the soybean seedlings was inhibited, the root morphology changed significantly, the activities of superoxide dismutase (SOD) and catalase (CAT) increased to a certain extent, the content of malondialdehyde (MDA) increased significantly, and the content of soluble sugar decreased after PS-NPs exposure. Transcriptome analysis showed that a total of 2112 differentially expressed genes were generated by PS-NPs exposure treatment, GO and KEGG analysis showed that they were mainly enriched in pathways related to redox reaction, reaction to ethylene and abscisic acid, amino acid metabolism and synthesis of other secondary metabolites. It was noted that 250 transcription factors were differentially expressed, mainly including the ERF, WRKY, NAC, bHLH and MYB transcription factor families. This experiment lays a foundation for further exploring the impact of nanoplastics on crops such as soybeans and its molecular mechanism. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the long‐term sexual function of patients with cervical cancer who underwent treatment and to explore influential factors. Methods: This retrospective cross‐sectional study was conducted at Peking University First Hospital in (Beijing, China). A total of 207 patients, who were diagnosed with Stage IA‐IIA cervical cancer and had undergone surgical treatment (some patients had also been treated with adjuvant radiotherapy and chemotherapy) between January 2010 and August 2020, completed questionnaires via telephone. The median time since diagnosis was 54 (range, 13–138) months. Sexual function was assessed using the validated short form of Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ‐12). The multivariate logistic regression analysis was performed to determine factors influencing sexual function after treatment. Results: The mean preoperative PISQ‐12 score was 39.42 ± 3.922, and the mean postoperative PISQ‐12 score was 32.60 ± 6.592, indicating a significant decrease in postoperative PISQ‐12 score compared with preoperation (p < 0.001). In total, 49.8% of the patients had sexual dysfunction after treatment. According to the results of the multivariate logistic regression analysis, longer follow‐up (months), ovariectomy, lack of hormone replacement therapy after ovariectomy and adjuvant radiotherapy were significantly associated with sexual dysfunction after treatment (p < 0.05). There was no significant correlation among surgical method, tumor stage, adjuvant chemotherapy, and sexual dysfunction after treatment. Conclusions: The sexual function of cervical cancer survivors significantly decreased after treatment, which was related to the length of follow‐up, ovariectomy, and adjuvant radiotherapy. Hormone replacement therapy after ovariectomy can help patients to improve their sexual function. [ABSTRACT FROM AUTHOR]

Isovalerate is one of the key intermediates during anaerobic digestion treating protein-containing waste/wastewater. Investigating the effect of different kinds of inhibitors on isovalerate-degrading microbial community is necessary to develop measures for improving the effectiveness of the treatment plants. In the present study, dynamic changes in the isovalerate-degrading microbial community in presence of inhibitors (ammonium, sulfide, mixed ammonium and sulfide, and chlortetracycline (CTC)) were investigated using high-throughput sequencing of 16S rRNA gene. Our observations showed that the isovalerate-degrading microbial community responded differently to different inhibitors and that the isovalerate degradation and gas production were strongly repressed by each inhibitor. We found that sulfide inhibited both isovalerate oxidation followed by methanogenesis, while ammonium, mixed ammonium and sulfide, and CTC mainly inhibited isovalerate oxidation. Genera classified into Proteobacteria and Chloroflexi were less sensitive to inhibitors. The two dominant genera, which are potential syntrophic isovalerate oxidizers, exhibited different responses to inhibitors that the unclassified_Peptococcaceae_3 was more sensitive to inhibitors than the unclassified_Syntrophaceae. Upon comparison to acetoclastic methanogen Methanosaeta, hydrogenotrophic methanogens Methanoculleus and Methanobacterium were less sensitive to inhibitors. [ABSTRACT FROM AUTHOR]

Propionate is one of the major intermediates in anaerobic digestion of organic waste to CO2 and CH4. In methanogenic environments, propionate is degraded through a mutualistic interaction between symbiotic propionate oxidizers and methanogens. Although temperature heavily influences the microbial ecology and performance of methanogenic processes, its effect on syntrophic interaction during propionate degradation remains poorly understood. In this study, metagenomics and metatranscriptomics were employed to compare mesophilic and thermophilic propionate degradation communities. Mesophilic propionate degradation involved multiple syntrophic organisms (Syntrophobacter, Smithella, and Syntrophomonas), pathways, interactions, and preference toward formate-based electron transfer to methanogenic partners (i.e., Methanoculleus). In thermophilic propionate degradation, one syntrophic organism predominated (Pelotomaculum), interspecies H2 transfer played a major role, and phylogenetically and metabolically diverse H2-oxidizing methanogens were present (i.e., Methanoculleus, Methanothermobacter, and Methanomassiliicoccus). This study showed that microbial interactions, metabolic pathways, and niche diversity are distinct between mesophilic and thermophilic microbial communities responsible for syntrophic propionate degradation. [ABSTRACT FROM AUTHOR]

Syntrophic oxidization of acetate and propionate are both critical steps of methanogenesis during thermophilic anaerobic digestion. However, knowledge on syntrophic acetate-oxidizing bacteria (SAOB) and syntrophic propionate-oxidizing bacteria (SPOB) is limited because of the difficulty in pure culture isolation due to symbiotic relationship. In this study, two thermophilic acetate-fed anaerobic chemostats, ATL (dilution rate of 0.025 day−1) and ATH (0.05 day−1) and one thermophilic propionate-fed anaerobic chemostat PTL (0.025 day−1) were constructed, AOB and POB in these chemostats were studied via microbial community analysis and DNA stable-isotope probing (SIP). The results showed that, in addition to Tepidanaerobacter, a known SAOB, species of Thauera, Thermodesulfovibrio, Anaerobaculum, Ruminiclostridium, Comamonas, and uncultured bacteria belonging to Lentimicrobiaceae, o_MBA03, Thermoanaerobacteraceae, Anaerolineaceae, Clostridiales, and Ruminococcaceae were determined to be potential AOB in chemostats. Pelotomaculum was the key SPOB detected in the propionate-fed chemostat. Based on the intense fluorescence of coenzyme F420, majority of Methanosarcina cells in acetate-fed chemostats were involved in hydrogenotrophic methanogenesis, suggesting the existence of highly active SAOB among the detected AOB. In the propionate-fed chemostat, most of the species detected as AOB were similar to those detected in the acetate-fed chemostats, suggesting the contribution of the syntrophic acetate oxidization pathway for methane generation. These results revealed the existence of previously unknown AOB with high diversity in thermophilic chemostats and suggested that methanogenesis from acetate via the syntrophic oxidization pathway is relevant for thermophilic anaerobic digestion. [ABSTRACT FROM AUTHOR]

Propionate is a crucial intermediate during methane fermentation. Investigating the effects of different kinds of inhibitors on the propionate-degrading microbial community is necessary to develop countermeasures for improving process stability. In the present study, under inhibitory conditions (acetate, propionate, sulfide, and ammonium addition), the dynamic changes of the propionate-degrading microbial community from a mesophilic chemostat fed with propionate as the sole carbon source were investigated using high-throughput sequencing of 16S rRNA. Sulfide and/or ammonia inhibited specific species in the microbial community. Compared with Syntrophobacter, Smithella was more resistant to inhibition by sulfide and/or ammonia. However, Syntrophobacter demonstrated greater tolerance than Smithella under acid inhibition conditions. Some genera that had close phylogenetic relationships and similar functions showed similar responses to different inhibitors. [ABSTRACT FROM AUTHOR]

Smoking is a well-known major risk factor in development of esophageal cancer, but few studies have reported the association between smoking status and prognosis of these patients. We conduct the present study to summarize current evidence. A computerized search of the PubMed and EMBASE was performed up to April 30, 2015. Eight studies, containing 4,286 patients, were analyzed. In the grouping analysis, among esophageal squamous-cell carcinoma patients, current and former smokers, compared to those who have never smoked, seemed to have a poorer prognosis (HR = 1.41, 95% CI 1.22–1.64, and HR = 1.35, 95% CI 0.92–1.97, resp.). In the subgroup analysis, adverse effects on current smoker compared with never smoker were also observed in China and the other countries (HR = 1.5, 95% CI 1.18–1.92, and HR = 1.36, 95% CI 1.12–1.65, resp.). In the group that ever smoked, we could not get a similar result. No significantly increased risk was found in esophageal adenocarcinoma patients compared to the squamous-cell histology ones. In the smoking intensity analysis, heavy smoking was associated with poor survival in esophageal squamous-cell carcinoma. Our pooled results supported the existence of harmful effects of smoking on survival after esophagus cancer diagnosis. [ABSTRACT FROM AUTHOR]

The feasibility of the anaerobic ammonium oxidation (anammox) process to treat synthetic swine wastewater containing antibiotics and heavy metals was studied in this work. Nitrogen removal performance and granule characteristics were tracked by continuous-flow monitoring to evaluate the long-term joint effects of Cu and Zn and of Cu and oxytetracycline (OTC). Cu and Zn with a joint loading rate (JLR) of 0.04 kg m day did not affect the performance, while a JLR of 0.12 kg m day caused a rapid collapse in performance. Cu and OTC addition with a JLR of 0.04 kg m day for approximately 2 weeks induced significant nitrite accumulation. Granule characteristic analysis elucidated the disparate inhibition mechanisms of heavy metals and antibiotics: the internalization of heavy metals caused metabolic disorders, whereas OTC functioned as a growth retarder. However, anammox reactors could adapt to a JLR of 0.04 kg m day via self-regulation during the acclimatization to subinhibitory concentrations, which had a stable nitrogen removal rate (>8.5 kg m day) and removal rate efficiency (>75 %) for reactors with Cu-OTC addition. Therefore, this study supports the great potential of using anammox granules to treat swine wastewater. [ABSTRACT FROM AUTHOR]

In the present study, the short- and long-term effects of Zn(II) on the anaerobic ammonium oxidation (anammox) performance and sludge characteristics were evaluated. The anammox activity decreased with increasing Zn(II) concentration and pre-exposure time in short-term tests. The half maximal inhibitory concentration (IC) of Zn(II) was found to be 25.0 mg L. The 24 and 48-h pre-exposure time was a restricted factor impacting the anammox activity, and washing the inhibited sludge with buffer solution only worked under 0 and 24-h pre-exposure time. The anammox sludge could tolerate 5 mg L Zn(II) but was suppressed at 8 mg L. The inhibited performance could be remitted, as the combination strategies were applied, and after the short term of recovery period, the inhibited sludge characteristics were remitted to the normal. [ABSTRACT FROM AUTHOR]

Dendrobium plants are important commercial herbs in China, widely used in traditional medicine and ornamental horticulture. In this study, sequence-related amplified polymorphism (SRAP) markers were applied to molecular phylogeny analysis and species identification of 31 Chinese Dendrobium species. Fourteen SRAP primer pairs produced 727 loci, 97% of which (706) showed polymorphism. Average polymorphism information content of the SRAP pairs was 0.987 (0.982-0.991), showing that plenty of genetic diversity exists at the interspecies level of Chinese Dendrobium. The molecular phylogeny analysis (UPGMA) grouped the 31 Dendrobium species into six clusters. We obtained 18 species-specific markers, which can be used to identify 10 of the 31 species. Our results indicate the SRAP marker system is informative and would facilitate further application in germplasm appraisal, evolution, and genetic diversity studies in the genus Dendrobium. [ABSTRACT FROM AUTHOR]

a popular flowering species with many cultivars, Cymbidium ensifolium (L.) is commercially important in horticulture. However, so far little has been known about genetic diversity and conservation genetics of this species. Understanding of the genetic variation and relationships in cultivars of C. ensifolium is a prerequisite for development of future germplasm conservation and cultivar improvement. Here we report assessment of genetic variations in C. ensifolium cultivars using the DNA fingerprinting technique of inter-simple sequence repeats (ISSR). A total of 239 ISSR loci were identified and used for evaluation of genetic variation with a selection of 19 ISSR primers. Among these ISSR loci, 99.16% were polymorphic with wide genetic variation as shown by Nei's gene diversity ( H = 0.2431) among 85 tested cultivars. ISSR fingerprinting profiles showed that each cultivar had its characteristic DNA pattern, indicating unequivocal cultivar identification at molecular level. Eighteen cultivar-specific ISSR markers were identified in seven cultivars. The cultivar Sijiwenhan was confirmed as hybrid by four ISSR primers. Several cultivars with same name but different geographical origins were distinguished based on their ISSR profiles. A dendrogram generated with ISSR markers could group 73 of 85 cultivars into four major clusters. Further analysis of ISSR variation revealed that about 69% of total genetic variation in this species is due to genetic divergence inside geographical groups. Our results suggest that both germplasm collection and in situ conservation are important for future planning of C. ensifolium species conservation. [ABSTRACT FROM AUTHOR]

We isolated and developed 13 novel microsatellite makers from expressed sequence tag sequences of endangered Chinese endemic herb Dendrobium officinale and examined them for 38 individuals from Jinhua, Zhejiang, Chian. These loci displayed the mean number of 4. 31 alleles per locus, and with expected heterozygosity ( H) and observed heterozygosity ( H) per locus ranged from 0.4438 to 0.6842 and from 0 to 0.4211, respectively. These markers have potential for application in germplasm appraisal, genetic diversity study, genetic mapping, and molecular breeding in D. officinale and other congeneric species. [ABSTRACT FROM AUTHOR]

Propionate is one of the most important intermediates of anaerobic fermentation. Its oxidation performed by syntrophic propionate-oxidizing bacteria coupled with hydrogenotrophic methanogens is considered to be a rate-limiting step for methane production. However, the current understanding of SPOB is limited due to the difficulty of pure culture isolation. In the present study, two anaerobic chemostats fed with propionate as the sole carbon source were operated at different dilution rates (0.05 d−1 and 0.15 d−1). The propionate- and acetate-oxidizing bacteria in the two methanogenic chemostats were investigated combining DNA-stable isotope probing (DNA-SIP) and 16S rRNA gene high-throughput sequencing. The results of DNA-SIP with 13C-propionate/acetate suggested that, Smithella, Syntrophobacter, Cryptanaerobacter, and unclassified Rhodospirillaceae may be putative propionate-oxidizing bacteria; unclassified Spirochaetaceae, unclassified Synergistaceae, unclassified Elusimicrobia, Mesotoga, and Gracilibacter may contribute to acetate oxidation; unclassified Syntrophaceae and Syntrophomonas may be butyrate oxidizers. By DNA-SIP, unclassified OTUs with 16S rRNA gene abundance higher than 62% of total Bacteria in the PL chemostat and 38% in the PH chemostat were revealed to be related to the degradation of propionate. These results suggest that a variety of uncultured bacteria contribute to propionate degradation during anaerobic digestion. The functions and metabolic characteristics of these bacteria require further investigation. [ABSTRACT FROM AUTHOR]