Redescription and Molecular Characterization of Trichotylenchus dispersus (Nematoda: Dolichodoridae) in China.

A species of Trichotylenchus nematode was isolated from the rhizosphere of banana root in Leizhou City, Guangdong Province, China. The species assumes the following characteristics: open C-shaped body; head offset from body; lateral field with three incisures, pharyngeal and tail regions irregularly areolated; stylet 18.6-20.7 µm long; pharyngeal gland not extending over intestine; fibrous tissue present in the intestine; post-anal intestinal sac present; elongate-subcylindroid tail, bluntly conoid terminus, lack of striations, and containing 34-44 annuli. In addition, scanning electron microscopy was used to elucidate some morphological details, but only some juveniles were observed. Partial 18S rRNA, ITS, and 28S D2-D3 expansion sequences were amplified with universal primers and deposited in GenBank under accession numbers ON622716, ON622717, and ON622714, respectively. Here, this species was identified as T. dispersus [(Siddiqi & Sharma, 1995) Geraert, 2011].

Assessment of long-term sexual function of cervical cancer survivors after treatment: A cross-sectional study.

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.

Proteiniphilum and Methanothrix harundinacea became dominant acetate utilizers in a methanogenic reactor operated under strong ammonia stress.

Microorganisms in anaerobic digestion (AD) are easily affected by ammonia, especially acetoclastic methanogens. Thus, in ammonia-suppressed AD systems, acetate degradation is reported to be carried out mainly by the cooperation of syntrophic acetate oxidizers and hydrogenotrophic methanogens. Previous studies have revealed ammonia inhibition on microbial flora by AD performance, but the effect mechanism of ammonia on microbial metabolism remains poorly understood. In this study, we constructed a mesophilic chemostat fed with acetate as the sole carbon source, gradually increased the total ammonia nitrogen (TAN) concentration from 1 g L-1 to 6 g L-1, and employed the 16S rRNA gene, metagenomics, and metatranscriptomics analysis to characterize the microbial community structure and metabolic behavior. The results showed that even at the TAN of 6 g L-1 (pH 7.5), the methanogenesis kept normal, the biogas production was approximately 92% of that at TAN of 1 g L-1 and the acetate degradation ratio reached 99%, suggesting the strong TAN tolerance of the microbial community enriched. 16S rRNA gene analysis suggested that the microbial community structure changed along with the TAN concentration. Methanothrix predominated in methanogens all the time, in which the dominant species was gradually replaced from M. soehngenii to M. harundinacea with the increased TAN. Dominant bacterial species also changed and Proteiniphilum showed a significant positive correlation with increased TAN. Meta-omics analysis showed that the absolute dominant microorganisms at TAN of 6 g L-1 were M. harundinacea and Proteiniphilum, both of which highly expressed genes for anti-oxidative stress. M. harundinacea and the second dominant methanogen Methanosarcina highly expressed both acetate cleavage and CO2 reduction pathways, suggesting the possibility that these two pathways contributed to methanogenesis together. Proteiniphilum and some other species in Firmicutes and Synergistetes were likely acetate oxidizers in the community as they highly expressed genes for syntrophic acetate oxidization, H2 generation, and electron transfer. These results suggested that Proteiniphilum as well as M. harundinacea have strong ammonia tolerance and played critical roles in acetate degradation under ammonia-suppressed conditions. The achievements of the study would contribute to the regulation and management of the AD process.

Different Interspecies Electron Transfer Patterns during Mesophilic and Thermophilic Syntrophic Propionate Degradation in Chemostats.

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.

Response of Isovalerate-Degrading Methanogenic Microbial Community to Inhibitors.

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.

Response to inhibitory conditions of acetate-degrading methanogenic microbial community.

Investigating the effects of different kinds of inhibitors on the activity and structure of acetate-degrading microbial community involved in methane fermentation is critically important for developing countermeasures to make the fermentation process stable under different inhibitory conditions. In the present study, a mesophilic chemostat fed with acetate as the sole carbon source was constructed. Microbial community analysis based on high-throughput sequencing of 16S rRNA revealed that Methanothrix was the dominant methanogen and a variety of bacteria including acetate-oxidizing bacteria such as Tepidanaerobacter, Mesotoga, Geovibrio, and Geobacter were found. The activity and dynamic changes of the acetate-degrading microbial community under different inhibitory conditions were investigated. Addition of 600 mg L-1 ammonium and 150 mg L-1 sulfide reduced nearly half of the biogas production. The response of microbial community to sulfide inhibition was quicker than ammonium but the structure could recover in a short time. Addition of 8 mg L-1 chlortetracycline (CTC) and 160 mg L-1 enrofloxacin (EFX) exhibited a similar inhibitory effect on biogas production, with approximately 35% reduction. Compared to ammonium and sulfide, antibiotics showed stronger selective inhibition on some bacterial species. The genera related to acetate-oxidizing and sulfate-reducing bacteria showed stronger tolerance to CTC, which may be due to their low growth rates. Network analysis suggested that some genera which had close phylogenic relationship and similar functions showed constant positive correlation under different inhibitory conditions.

Using DNA-based stable isotope probing to reveal novel propionate- and acetate-oxidizing bacteria in propionate-fed mesophilic anaerobic chemostats.

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.

Identification of novel potential acetate-oxidizing bacteria in thermophilic methanogenic chemostats by DNA stable isotope probing.

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.

Response of Propionate-Degrading Methanogenic Microbial Communities to Inhibitory Conditions.

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.

Identification of novel potential acetate-oxidizing bacteria in an acetate-fed methanogenic chemostat based on DNA stable isotope probing.

Acetate is a significant intermediate of anaerobic fermentation. There are two pathways for converting acetate to CH4 and CO2: acetoclastic methanogenesis by acetoclastic methanogens, and syntrophic acetate oxidation by acetate-oxidizing bacteria (AOB) and hydrogenotrophic methanogens. Detailed investigations of syntrophic acetate-oxidizing bacteria (SAOB) should contribute to the elucidation of the microbial mechanisms of methanogenesis. In this study, we investigated the major phylogenetic groups of acetate-utilizing bacteria (AUB) in a mesophilic methanogenic chemostat fed with acetate as the sole carbon source by using DNA stable isotope probing (SIP) technology. The results indicated that acetoclastic methanogenesis and acetate oxidization/hydrogenotrophic methanogenesis coexisted in the mesophilic chemostat fed with acetate, operated at a dilution rate of 0.1 d-1. OTU Ace13(9-17) (KU869530), Ace13(9-4) (KU667241), and Ace13(9-23) (KU667236), assigned to the phyla Firmicutes and Bacteroidetes, were probably potential SAOB in the chemostat, which needs further investigation. Species in the phyla Proteobacteria, Deferribacteres, Acidobacteria, Spirochaetes and Actinobacteria were probably capable of utilizing acetate for their growth. Methanoculleus was likely to be the preferred hydrogenotrophic methanogen for syntrophy with AOB in the chemostat.

[Application of DNA molecular marker technologies in study of medicinal Physalis species].

As traditional Chinese medicinal herbs, Physalis plants have a variety of pharmacological activities, such as anti-inflammatory, anti-oxidant, and anti-cancer effects, and have been used for the treatment of malaria, rheumatism, hepatitis, asthma, and cancer. In addition to the medicinal value, many Physalis species are also the high-grade nutrition health care fruits, can be made canned and candied etc. In the study, the application progress of DNA molecular marker technologies in medicinal Physalis plants in recent years was reviewed, in order to provide an important molecular technical basis for the identification, classification and rational development and protection of medicinal Physalis resources.

Smoking Exposure and Survival of Patients with Esophagus Cancer: A Systematic Review and Meta-Analysis.

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.

Long-term effects of heavy metals and antibiotics on granule-based anammox process: granule property and performance evolution.

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(-3) day(-1) did not affect the performance, while a JLR of 0.12 kg m(-3) day(-1) caused a rapid collapse in performance. Cu and OTC addition with a JLR of 0.04 kg m(-3) day(-1) 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(-3) day(-1) via self-regulation during the acclimatization to subinhibitory concentrations, which had a stable nitrogen removal rate (>8.5 kg m(-3) day(-1)) 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.

Behavior and fate of copper ions in an anammox granular sludge reactor and strategies for remediation.

In this study, the behavior, distribution and form dynamics of overloaded Cu(II) in anaerobic ammonium oxidation (anammox) granular sludge reactors were investigated. The performance and physiological characteristics were tracked by continuous-flow monitoring to evaluate the long-term effects. High Cu loading (0.24 g L(-1)d(-1)) exceeded sludge bearing capacity, and precipitation dominated the removal pathway. The Cu distribution migrated from the extracellular polymeric substances-bound to the cell-associated Cu and the Cu forms shifted from the weakly bound to strongly bound fractions over time. Pearson correlation and fluorescence spectra analyses showed that the increase in protein concentrations in the EPS was a clear self-defense response to Cu(II) stress. Two remediation strategies, i.e., ethylenediamine tetraacetic acid (EDTA) washing and ultrasound-enhanced EDTA washing, weakened the equilibrium metal partition coefficient from 5.8 to 0.45 and 0.34 L mg(-1)SS, respectively, thereby accelerating the external diffusion of the Cu that had accumulated in the anammox granules.

Analyzing the revolution of anaerobic ammonium oxidation (anammox) performance and sludge characteristics under zinc inhibition.

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 (IC50) of Zn(II) was found to be 25.0 mg L(-1). 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(-1) Zn(II) but was suppressed at 8 mg L(-1). 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.

Optimization of process performance in a granule-based anaerobic ammonium oxidation (anammox) upflow anaerobic sludge blanket (UASB) reactor.

In this study, the individual and interactive effects of influent substrate concentration (TNinf), hydraulic retention time (HRT) and upflow velocity (Vup) on the performance of anaerobic ammonium oxidation (anammox) in a granule-based upflow anaerobic sludge blanket (UASB) reactor were investigated by employing response surface methodology (RSM) with a central composite design. The purpose of this work was to identify the optimal combination of TNinf, HRT and Vup with respect to the nitrogen removal efficiency (NRE) and nitrogen removal rate (NRR). The reduced cubic models developed for the responses indicated that the optimal conditions corresponded to a TNinf content of 644-728mgNL(-1), an HRT of 0.90-1.25h, and a Vup of 0.60-1.79mh(-1). The results of confirmation trials were similar to the predictions of the developed models. These results provide useful information for improving the nitrogen removal performance of the anammox process in a UASB reactor.

Floatation of flocculent and granular sludge in a high-loaded anammox reactor.

The floatation of flocculent and granular sludge was investigated in this study. An anaerobic ammonium oxidation (anammox) upflow anaerobic sludge blanket (UASB) reactor was operated for 665 days. During this time, the maximum nitrogen removal rate was 52.6 kg Nm(-3) d(-1). Floccule floatation occurred between days 100 and 140, which potentially resulted from the sudden increase in gas yield and the poor settling ability of the floccules. Increasing the shear rate from 0.084 to 0.135 s(-1) was effective at eliminating floccule floatation. In addition, granule floatation occurred between days 572 and 665, which likely resulted from the formation of hollows within the granules. Floatation may be effectively prevented by maintaining a shear rate of more than 0.778 s(-1). Furthermore, the mechanisms of granule floatation and the floatation processes were proposed. Overall, controlling the shear force may effectively overcome sludge floatation.

Bio-augmentation for mitigating the impact of transient oxytetracycline shock on anaerobic ammonium oxidation (ANAMMOX) performance.

The feasibility of applying bio-augmentation tactics to remit the influence of transient oxytetracycline (OTC) shock on the anaerobic ammonium oxidation (ANAMMOX) process was evaluated. The bio-augmentation was applied together with shock test, with OTC shock concentration of 518 mg L(-1) and 1-h duration. 0.655-2.62 g volatile suspended solid (VSS) sludges were varied to optimize bio-augmentation dosage (BAD), and appropriate bio-augmentation time (BAT) was determined. The validity of the bio-augmentation was indicated by recovery performance and sludge characteristics. The restoring time of 38 h for bio-augmented reactor was shorter than that of non-bio-augmented reactor (45 h), and heme c content was increased respectively from 0.195 ± 0.001, 0.267 ± 0.047, 0.301 ± 0.049, to 0.340 ± 0.053 µmol g(-1) VSS with the BAD of 0.655, 1.31, 1.97, 2.62 g-VSS. The results suggest that bio-augmentation enhances the recovery of ANAMMOX performance following OTC shock and BAT and BAD are key operational factors.

Molecular phylogeny analysis and species identification of Dendrobium (Orchidaceae) in China.

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.