Enhancing anaerobic degradation of oily sludge using subcritical hydrothermal pretreatment

AIMS

Oily sludge is a kind of mixture that is extremely harmful to the environment. Anaerobic digestion (AD) is a commonly used method for biodegrading oily sludge. However, the AD treatment cycle is usually long and inefficient. Here, we developed an approach to improve the degradation rate of oily sludge by integrating subcritical hydrothermal pretreatment (SHP) and AD.

METHODS AND RESULTS

First, using SHP, the hydrocarbon compounds with long carbon chains that make up oil sludge were decomposed into hydrocarbons with short carbon chains, which are conducive to microbial decomposition and transformation. Then, AD was performed using a variety of temperature and solid-liquid ratio parameters. The results showed that the degradation ratio of oily sludge was higher when SHP was combined with AD than when no pre-treatment was performed. Optimal degradation was reached by performing SHP to obtain CHS8, then performing AD at 30°C using a 1:5 solid-liquid ratio. Under these conditions, maximum degradation ratios of 69·00% of TOC, 59·02% of COD, 44·68% of ammonia and 54·24% of oil content were reached.

CONCLUSIONS

In conclusion, after SHP with 8% dilute sulphuric acid, most of the macromolecular hydrocarbons in the oily sludge were converted into smaller molecules, which facilitated subsequent microbial decomposition. The results showed that this combination of SHP and AD processes promotes more efficient degradation than a conventional single AD process without any hydrothermal pretreatment.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our experiments provide technical support for enhancing the rapid degradation of oily sludge.

Cytotoxic Lesion of the Corpus Callosum in an Adolescent with Multisystem Inflammatory Syndrome and SARS-CoV-2 Infection

Multisystem inflammatory syndrome in children is a recently described complication in the late phase of Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection involving systemic hyperinflammation and multiorgan dysfunction. The extent of its clinical picture is actively evolving and has yet to be fully elucidated. While neurologic manifestations of SARS-CoV-2 are well-described in the adult population, reports of neurologic complications in pediatric patients with SARS-CoV-2 infection are limited. We present a pediatric patient with SARS-CoV-2 infection with development of multisystem inflammatory syndrome and acute encephalopathy causing delirium who was found to have a cytotoxic lesion of the corpus callosum on neuroimaging. Cytotoxic lesions of the corpus callosum are a well-known, typically reversible entity that can occur in a wide range of conditions, including infection, seizure, toxins, nutritional deficiencies, and Kawasaki disease. We hypothesized that the cytotoxic lesion of the corpus callosum, in the index case, was secondary to the systemic inflammation from SARS-CoV-2 infection, resulting in multisystem inflammatory syndrome in children.

Reproducibility of Histologic Assessment in Porto-sinusoidal Vascular Disease Liver Biopsies

Introduction/Objective

Variable histologic findings that may be seen in porto-sinusoidal vascular disease (PSVD) liver biopsies are subject to high interobserver variability, requiring correlation with clinical history of portal hypertension (traditionally interpreted as non-cirrhotic portal hypertension NCPH). We investigated which histologic features are reproducible in PSVD biopsies.

Methods

Archived liver biopsies (n=38) from patients with NCPH (n=14) and without NCPH (n=21) were reviewed. Static H&E images of lobules (L, x100, NCPH=27, non-NCPH=23) and portal tracts (P, x200, NCPH=23, non- NCPH=27) were distributed among 9 gastrointestinal pathologists blinded to clinical history. Each pathologist answered multiple choice questions based on the presence (Q2) or absence (Q1) of portal hypertension clinically. The choice selected by 6 pathologists or more was considered consensus answer for the image. The interpretation of the image was considered reproducible when consensus was reached on both Q1 and Q2.

Results

The interpretations of 27 (54%; 17L, 10P) images from NCPH and 21 (42%; 10L, 11P) from non-NCPH were reproducible. In NCPH, the interpretations of normal (n=10, 4L, 6P), sinusoidal dilatation (n=7), and increased parenchymal draining vessels (n=3) were reproducible, while there was no consensus on the diagnoses of nodular regeneration and increased number of portal vessels. In non-NCPH, the interpretations of normal (n=8, 2L, 6P), sinusoidal dilatation (n=6), and paraportal shunting vessel(s) (n=4) were reproducible, whereas no consensus was reached on the diagnoses of nodular regeneration, incomplete fibrous septa, and increased number of portal vessels.

Conclusion

Histologic assessment of normal L and P as well as sinusoidal dilatation appears to be reproducible independent of clinical history. The findings of increased parenchymal draining vessels in NCPH group and paraportal shunting vessels in non-NCPH group may be consistently diagnosed to a certain extent. The assessment for nodular regeneration without reticulin stain, incomplete fibrous septa, or increased number of portal vessels appears to be unreliable.

PTEN expression in U251 glioma cells enhances their sensitivity to ionizing radiation by suppressing DNA repair capacity

OBJECTIVE

Mutations in phosphatase and tensin homologue deleted on chromosome 10 (PTEN), a tumor suppressor gene, lead to altered sensitivity to drugs and radiation in various types of cancer. Restoring PTEN expression in tumor cells can increase radiosensitivity by inhibiting the repair of DNA double-strand breaks (DSBs). Thus, determining the mechanism of action of this protein may lead to novel therapeutic strategies.

MATERIALS AND METHODS

In this study, we transduced U251 cells with a lentiviral vector expressing PTEN to examine the mechanism of radiosensitization. Specifically, we examined the formation of radiation-induced DNA DSBs and apoptosis, as well as the expression of several proteins involved in repairing DSBs (p53, ataxia-telangiectasia mutated, DNA-dependent protein kinase C, Ku70-80).

RESULTS

Our results showed that PTEN transduction sensitized U251 cells to X-rays, increasing the number of DSBs per cell and fraction of cells undergoing apoptosis. Additionally, the average size of γH2AX nuclear foci was increased following irradiation. These findings were accompanied by a PTEN-dependent irradiation-independent increase in p53 levels and decrease in phosphorylated Ku70/80 levels.

CONCLUSIONS

Our results suggest that PTEN affects radiosensitivity by reducing DSB repair and by enhancing the p53 pathway, leading to increased apoptosis.

Long noncoding RNA LSINCT5 is upregulated and promotes the progression of esophageal squamous cell carcinoma

OBJECTIVE

Long stress-induced noncoding transcripts 5 (LSINCT5) has been reported to be upregulated in several human cancers and related to poor prognosis. However, its involvement in esophageal squamous cell carcinoma (ESCC) remains largely unknown. We aim to evaluate the expression and putative role of LSINCT5 on the progression of ESCC.

MATERIALS AND METHODS

LSINCT5 expression was first examined in the ESCC cell lines using RT-qPCR, and the next-generation RNA-Seq technology was employed to analyze and functionally annotate the differential gene expression before and after LSINCT5 knockdown in ESCC was made. Based on the functional annotation results, the effects of LSINCT5 knockdown on cell growth, migration, invasion, and epithelial-to-mesenchymal transition (EMT) were assessed in the ESCC cell lines. Finally, the expression and clinicopathological significance of LSINCT5 in ESCC and corresponding nontumor tissues were further explored using RT-qPCR.

RESULTS

The RT-qPCR results showed that LSINCT5 expression was significantly upregulated in the ESCC cell lines. The differential gene expression analysis by next-generation RNA-Seq showed that 138 genes were up-regulated, and 227 genes were downregulated after LSINCT5 was knocked down in the ECA 109 cells. In addition, the functional annotation revealed that the differentially expressed genes were mainly functionally involved in tight junctions, ECM-receptor interactions, and MAPK signaling pathway. Further in vitro studies indicated that the knockdown of LSINCT5 significantly suppressed proliferation, migration, invasion, and EMT in ESCC cells. Finally, a comparative study of paired ESCC and corresponding nontumor tissues showed that LSINCT5 was upregulated in the ESCC tissues, and the increased LSINCT5 expression was related to late clinical stages, large tumor sizes, and lymph node metastasis.

CONCLUSIONS

The results indicate that LSINCT5 is upregulated in ESCC and may act as an oncogene promoting the progression of ESCC.

LINC00052 inhibits tumor growth, invasion and metastasis by repressing STAT3 in cervical carcinoma

OBJECTIVE

The vital role of long noncoding RNAs (lncRNAs) in tumor progression has been identified in numerous studies. In this research, the biological function of lncRNA LINC00052 during the development of cervical cancer was mainly explored.

PATIENTS AND METHODS

LINC00052 expression was detected by quantitative Real-time polymerase chain reaction (qRT-PCR) in cervical cancer tissue samples and cell lines. Moreover, the correlation between LINC00052 expression level and disease-free survival rate of cervical cancer patients was analyzed. In vitro functions of LINC00052 in cervical cancer cells were evaluated by proliferation assay, wound healing assay and transwell assay. In addition, qRT-PCR and Western blot were utilized to explore the underlying mechanism of LINC00052 in mediating the progression of cervical cancer.

RESULTS

LINC00052 expression level was lower in cervical cancer samples than that in adjacent tissues, which was correlated with disease-free survival time. Moreover, cell proliferation, migration and invasion were inhibited through overexpression of LINC00052 in vitro. The mRNA and protein expression of signal transducers and activators of transcription 3 (STAT3) was downregulated after overexpressing LINC00052 in cervical cancer cells. The STAT3 expression level was negatively correlated with the expression of LINC00052 in cervical cancer tissues.

CONCLUSIONS

LINC00052 could repress metastasis and invasion of cervical cancer cell via suppressing STAT3. LINC00052 might be a novel tumor suppressor in cervical cancer.