Comparative evaluation on the utilization of applied electrical potential in a conductive granule packed biotrickling filter for continuous abatement of xylene: Performance, limitation, and microbial community

This study investigates the use of electrically conductive granules as packing material in biotrickling filter (BTF) systems as to provide insights on the specific microbial abundance and functions during the treatment of xylene-containing waste gas. In addition, the effect of applied potential on attached biofilm on conductive granules during xylene degradation was briefly investigated. During stable operation period, the conductive granules packed BTF achieved reactor performance of no less than 80% with a maximum EC of 137.7 g/m³ h. Under applied potential of 1V, the BTF system showed deterioration of xylene removal by ranging from 21 to 76%, which also affected the distribution and relative abundance of the major microorganisms such as Xanthobacter, Acidovorax, Rhodococcus, Hydrogenophaga, Arthrobacter, Brevundimonas, Pseudoxanthomonas, Devosia, Shinella, Sphingobium, Dokdonella, Pseudomonas and Bosea. The acclimation of applied potential led to the enrichment of autotrophic bacteria and strains, which are correlated to improved nitrogen cycling. In general, applying electrical potential is feasible to shape the microbiological structure of biofilms to selectively adjust their biochemical functions.

NGS-based profiling reveals a critical contributing role of somatic D-loop mtDNA mutations in HBV-related hepatocarcinogenesis

BACKGROUND

Somatic mutations of mitochondrial DNA (mtDNA) have been extensively identified mainly by traditional Sanger sequencing technology in various cancer types. However, low detection sensitivity of traditional methods greatly limits the comprehensive profiling of mtDNA somatic mutations in cancers, especially in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Moreover, the functional roles of mtDNA mutation in HBV-related hepatocarcinogenesis have not been systematically revealed.

PATIENTS AND METHODS

Next-generation sequencing (NGS) platform was applied to profile the somatic mtDNA mutations of HCC and paired paratumor (non-HCC) tissues from a large cohort of 156 HBV-HCC patients.

RESULTS

Our data revealed the common existence of mtDNA mutation in both inflammatory and cancer tissues with significantly different mutation pattern. The mutation density (mutation number/region length) of D-loop region was much higher than that of other regions in both HCC and non-HCC tissues. Unexpectedly, the average mutation number in D-loop region of HCC tissues was significantly less than that of non-HCC tissues. In contrast, the heteroplasmy level of D-loop region mutations was significantly increased in HCC tissues, implying that the D-loop mutations might be positively selected in HCC tissues. Furthermore, our results indicated that the patients with D-loop mutations had a significantly lower mtDNA copy number and were more likely to relapse. In vitro experiments demonstrated that proliferation, invasion and metastasis ability of HCC cells with D-loop region mutations were significantly higher than those without D-loop region mutations.

CONCLUSION

These results emphasize the critical contributing role of somatic mtDNA D-loop mutations in HBV-related hepatocarcinogenesis.

Palmatine alleviates hyperalgesia by inhibiting the expression of calcitonin gene-related peptide in the trigeminal ganglion of rats with chronic constriction injury of the infraorbital nerve

Trigeminal neuralgia is one of the most common of the neuropathic pains, and it can seriously influence patients' quality of life. Calcitonin gene-related peptide (CGRP) is a type of nociceptive neurotransmitter that is expressed in neurons of the trigeminal ganglion and plays a major part in transmitting pain. The rat model of trigeminal neuralgia was established by causing a chronic constriction injury of the infraorbital nerve (CCI-ION). Male Sprague-Dawley rats (n=24) were randomly divided into a sham control group (sham, n=6), sham-treated with palmatine group (sham+palmatine, n=6), trigeminal nerve model group (TN, n=6), and trigeminal nerve treated with palmatine group (TN+palmatine, n=6). Fifteen days after the operation the mechanical response threshold was decreased in the TN group compared with the sham group. From postoperative day 7 to day 15, the mechanical response threshold in the TN+palmatine group significantly increased compared with the TN group. On postoperative day 15 the results of quantitative polymerase chain reaction (qPCR), immunohistochemical staining, and western blotting showed an obvious increase in expression of CGRP and its receptors, serum concentrations of interleukin-1β (IL-1β), and tumour necrosis factor-α (TNF-α), and phosphorylation of protein kinase C (PKC) in the trigeminal ganglia of the TN group compared with the sham group, but these increases could be down-regulated by treatment with palmatine. Palmatine might therefore have therapeutic potential for the treatment of trigeminal neuralgia by inhibiting the expression of CGRP and its receptors in trigeminal ganglia, suppressing the serum concentrations of IL-1β and TNF-α, and decreasing the phosphorylation of PKC in the trigeminal ganglia of affected rats.

Production of Rare Ginsenosides Rg3 and Rh2 by Endophytic Bacteria from Panax ginseng

The ginsenosides Rh2 and Rg3 induce tumor cell apoptosis, inhibit tumor cell proliferation, and restrain tumor invasion and metastasis. Despite Rh2 and Rg3 having versatile pharmacological activities, contents of them in natural ginseng are extremely low. To produce ginsenosides Rh2 and Rg3, the saponin-producing capacity of endophytic bacteria isolated from Panax ginseng was investigated. In this work, 81 endophytic bacteria isolates were taken from ginseng roots by tissue separation methods. Among them, strain PDA-2 showed the highest capacity to produce the rare ginsenosides; the concentrations of rare ginsenosides Rg3 and Rh2 reached 62.20 and 18.60 mg/L, respectively. On the basis of phylogenetic analysis, it was found that strain PDA-2 belongs to the genus Agrobacterium and was very close to Agrobacterium rhizogenes.

Effects of aging, baseline renal function and stage of HIV infection on post-treatment changes in renal function among HIV-infected patients: a retrospective cohort study

OBJECTIVES

The use of combination antiretroviral therapy (cART) increases clinical uncertainty about changes in renal function. Specifically, little is known regarding the interaction of the effects of aging, baseline renal impairment, and stages of HIV infection on post-treatment changes in renal function.

METHODS

This analysis included 5533 HIV-infected patients on cART in 2004-2016. Progression to chronic kidney disease (CKD) was defined as either two consecutive estimated glomerular filtration rate (eGFR) measurements < 60 mL/min/1.73 m² for baseline eGFR ≥ 60 mL/min/1.73 m² (mild renal impairment or normal renal function) or a 25% decline for baseline eGFR < 60 mL/min/1.73 m² (moderate renal impairment).

RESULTS

During follow-up (median 4.8 years), 130 (2.3%) of the patients progressed to CKD. A total of 20.1% of patients with baseline normal renal function progressed to mild renal impairment, while 74.0% of patients with baseline mild or moderate renal impairment improved to normal renal function. In multivariable analysis, a significant positive baseline-eGFR-by-World Health Organization (WHO)-stage interaction effect on progression to CKD in all patients was identified, indicating a cross-over effect from a reduced risk to an increased risk. A significant negative baseline-age-by-WHO-stage interaction effect on progression to mild renal impairment in patients with baseline normal renal function was identified, with adjusted hazard ratios progressively lower at older ages. In addition, there were significant associations with older age, lower baseline eGFR, Dai ethnic minority, and anaemia for both outcomes, hyperglycaemia for CKD only, and higher CD4 count, tenofovir and ritonavir-boosted lopinavir use for mild renal impairment only.

CONCLUSIONS

Our data suggest a complex pattern of renal function dynamics in patients on cART, which requires precise management with systematic monitoring of the interaction of the effects of sociodemographic, nephrological and HIV-specific clinical characteristics.

[Long non-coding RNA HULC affects downstream-related targets to regulate migration and invasion of hepatoma cells]

Objective: To investigate the effects of long non-coding RNA HULC on downstream related targets regulating the migration and invasion of hepatoma cells and theirs mechanism of action. Methods: The expression of highly upregulated in liver cancer (HULC) in hepatocellular carcinoma, and adjacent normal liver tissues and different hepatocellular carcinoma cells were detected by qPCR. The correlation between clinicopathological data of HULC and liver cancer patients were analyzed. Dual-luciferase reporter gene detected the interaction between HULC and miR-186. CCK-8 assay was used to detect the effect of HULC on proliferation of hepatocellular carcinoma cells. The change in hepatocellular carcinoma cell invasions ability after HULC inhibition was detected by transwell invasion assay and migration ability after inhibition of HULC was assessed by scratch assay. Differences between groups were compared using one-way ANOVA. P < 0.05 was considered statistically significant. Results: Compared with adjacent normal liver tissue, the expression of HULC in hepatocellular carcinoma was significantly higher [(1.79 ± 0.25) vs. (0.23 ± 0.05), P < 0.05]. The expression level of HULC was highest in hepatocellular carcinoma HepG3 cells. HULC specifically banded to the 3'UTR of miR-186 and regulated the expressional activity of miR-186. After inhibiting the expression of HULC, the proliferation of hepatocellular carcinoma cells was 72 h (0.35 ± 0.09) vs. (0.82 ± 0.16), P < 0.05; 96 h (0.42 ± 0.08) vs.(1.28 ± 0.19), P < 0.05), and the ability of migration and invasion was relatively decreased in 24 h (11.2% ± 1.6%) vs. (23.5% ± 3.6%), P < 0.05; 48 h (18.6% ± 3.0%) vs. (38.6% ± 5.6%), P < 0.05; 72 h (43.6% ± 5.3% ) vs. (69.6% ± 7.6%), P < 0.05]. After inhibiting the expression of HULC, the tumor volume and body weight of tumor-bearing mice were significantly reduced [volume (2.89 ± 0.29) cm(3) vs. (0.89 ± 0.18) cm(3), P < 0.05, body weight (3.18 ± 0.41) g vs. (0.45 ± 0.09) g, P < 0.05]. Conclusion: HULC plays an important role in the occurrence and development of hepatocellular carcinoma and can influence the biological behavior of hepatoma cells by regulating the expression of downstream-related targets.

Recent progress and perspectives in biotrickling filters for VOCs and odorous gases treatment

Pollution caused by volatile organic compounds (VOCs) and odorous pollutants in the air can produce severe environmental problems. In recent years, the emission control of VOCs and odorous pollutants has become a crucial issue owing to the adverse effect on humans and the environment. For treating these compounds, biotrickling filter (BTF) technology acts as an environment friendly and cost-effective alternative to conventional air pollution control technologies. Besides, low concentration of VOCs and odorous pollutants can also be effectively removed using BTF systems. However, the VOCs and odorants removal performance by BTF may be limited by the hydrophobicity, toxicity, and low bioavailability of these pollutants. To solve these problems, this review summarizes the design, mechanism, and common analytical methods of recent BTF advances. In addition, the operating conditions, mass transfer, packing materials and microorganisms (which are the critical parameters in a BTF system) were evaluated and discussed in view of improving the removal performance of BTFs. Further research on these specific topics, together with the combination of BTF technology with other technologies, should improve the removal performance of BTFs.

Enhancement of TCE removal by a static magnetic field in a fungal biotrickling filter

A fungal biotrickling filter (BTF) was employed to treat trichloroethylene (TCE) gas under different magnetic field intensities (MFIs). When the TCE inlet concentrations were approximately 370, 500-900, and 1000 mg/m³, the removal performances followed the order: MFI 20.0 mT > MFI 60.0 mT > MFI 80.0 mT > MFI 0 mT. In particular, at a TCE inlet concentration of 1000 mg/m³, MFI 20.0 mT was significantly better than MFI 0 mT performance. The corresponding removal efficiencies and maximum elimination capacities were 52.9%, 4854.1 mg/m³ h and 39.4%, 3594.8 mg/m³ h, respectively. BTF was shut down completely for 7 days and rapidly recovered in 6-10 days. High-throughput sequencing indicated that MF significantly affected the fungal community and significantly improved the relative abundance of the phylum Ascomycota, achieving the highest abundance of Ascomycota at MFI 20.0. These results indicated that a lower MFI can efficiently improve TCE removal performance in a fungal BTF.

Electricity generation and removal performance of a microbial fuel cell using sulfonated poly (ether ether ketone) as proton exchange membrane to treat phenol/acetone wastewater

The microbial fuel cell (MFC) has emerged as a promising technology for wastewater treatment and energy recovery, but the expensive cost of proton exchange membranes (PEMs) is a problem that need to be solved. In this study, a two-chamber MFC based on our self-made PEM sulfonated poly (ether ether ketone) membrane was set up to treat phenol/acetone wastewater and synchronously generate power. The maximum output voltage was 240-250 mV. Using phenol and acetone as substrates, the power generation time in an operation cycle was 289 h. The MFC exhibited good removal performance, with no phenol or acetone detected, respectively, when the phenol concentration was lower than 50 mg/L and the acetone concentration was lower than 100 mg/L. This study provides a cheap and eco-friendly way to treat phenol/acetone wastewater and generate useful energy by MFC technology.

Performance and bacterial diversity of biotrickling filters filled with conductive packing material for the treatment of toluene

Toluene has high toxicity and mutagenicity, thus, the removal of toluene from air is necessary. In this study, two biotrickling filters (BTFs) were constructed and packed with conductive packing material to treat toluene waste gas. BTF-O exhibited good toluene removal performance even under high toluene inlet concentration, and over 80% of removal efficiency was observed. The elimination capacity reached 120.1 g/m³ h corresponding to an inlet concentration of 2.259 g/m³ under 61.5 s of empty bed retention time. During toluene biodegradation, the output voltage was observed in BTF-O and BTF-E, moreover BTF-E also showed slight power storage capacity. The applied voltage inhibited toluene removal and affected the bacterial community. The predominant bacterial genera in BTF-O were Acidovorax, Rhodococcus, Hydrogenophaga, Brevundimonas, Arthrobacter, Pseudoxanthomonas, Devosia, Gemmobacter, Rhizobium, Dokdonella and Pseudomonas. Genera Xanthobacter and Pelomonas accounted for the main bacterial community in BTF-E.

DNAH6 is a novel candidate gene associated with sperm head anomaly

Globozoospermia and acephalic spermatozoa are two rare sperm head anomalies associated with male infertility. Combination of the two phenotypes in the same patient is extremely rare, so the underlying pathogenesis of this disorder remains unclear. Here, we report a 35-year-old infertile male, who presented with 30% of sperm-lacked heads and 69% of sperm round-headed or small-headed with neck thickening in his ejaculate. Subsequent whole-exome sequencing (WES) analysis identified compound heterozygous variants within the DNAH6 gene. DNAH6 is a testis-specific-expressed protein that was localised to the neck region in the spermatozoa of normal control; however, immunofluorescent staining failed to detect DNAH6 protein in the patient's spermatozoa. Quantitative real-time PCR analysis also showed the complete absence of DNAH6 mRNA in the patient's spermatozoa. Moreover, two cycles of in vitro fertilisation (IVF)-assisted reproduction were carried out, but pregnancy was not achieved after embryo transfer. Therefore, rare sequence variants in DNAH6 might be susceptibility risks for human sperm head anomaly.

Effect of static magnetic field on trichloroethylene removal in a biotrickling filter

A laboratory-scale biotrickling filter combined with a magnetic field (MF-BTF) and a single BTF (S-BTF) were set up to treat trichloroethylene (TCE) gas. The influences of phenol alone and NaAc-phenol as co-substrates and different MF intensities were investigated. At low MF intensity, MF-BTF displayed better performance with 0.20g/L of phenol, 53.6-337.1mg/m³ of TCE, and empty bed residence times of 202.5s. The performances followed the order MF-BTF (60.0mT)>MF-BTF (30.0mT)>S-BTF (0mT)>MF-BTF (130.0mT), and the removal efficiencies (REs) and maximum elimination capacities (ECs) corresponded to: 92.2%-45.5%, 2656.8mg/m³h; 89.8%-37.2%, 2169.1mg/m³h; 89.8%-29.8%, 1967.7mg/m³h; 76.0%-20.8%, 1697.1mg/m³h, respectively. High-throughput sequencing indicated that the bacterial diversity was lower, whereas the relative abundances of Acinetobacter, Chryseobacterium, and Acidovorax were higher in MF-BTF. Results confirmed that a proper MF could improve TCE removal performance in BTF.