[In vitro activity of β-lactamase inhibitors avibanvctam and relebactam in combination with β-lactams against multidrug-resistant Mycobacterium tuberculosis and mutations of resistance genes]

Objective: To evaluate the activity of six β-lactams in combination with three β-lactamase inhibitors against mycobacterium tuberculosis(MTB) in vitro. Methods: A total of 105 multidrug-resistant tuberculosis (MDR-TB) strains from different regions of Henan province from January to September 2020 were included in this study. Drug activity of six β-lactams (biapenem, meropenem, imipenem, doripenem, ertapenem and tebipenem) alone or in combination with β-lactamase inhibitors (clavulanic acid, avibactam and relebactam) was examined by minimum inhibitory concentration method (MICs) against 105 clinical isolates. Mutations of blaC, ldtmt1 and ldtmt2 were analyzed by PCR and DNA sequencing. Chi-square test was used to compare the antimicrobial activities of different β-lactam drugs. Results: Out of the β-lactams used herein, tebipenem was the most effective against MDR-TB and had an MIC50 value of 8 mg/L(χ2=123.70,P=0.001). Besides, after the addition of β-lactamase inhibitors, the MICs of most β-lactam drugs were reduced more evidently in the presence of avibactam and relebactam compared to clavulanic acid.Especially, relebactam decreased both the MIC50 and MIC90 of telbipenem by 16-fold, and diluted the MIC of 23 (21.90%) and 41 (39.04%) isolatesby 32-fold and 16-fold.In addition, a total of 13.33% (14/105) of isolates harbored mutations in the blaC gene, with three different nucleotide substitutions: AGT333AGG, AAC638ACC and ATC786ATT. For the strains with Ser111Arg and Asn213Thr substitution in BlaC, the MIC values of the meropenem-clavulanate combination were reduced compared with a synonymous single nucleotide polymorphism (SNP) group. Conclusions: Both avibactam and relebactam had better synergistic effects on β-lactams than clavulanic acid. The combination of tebipenem and relebactam showed the most potent activity against MDR-TB isolates. In addition, the Ser111Arg and Asn213Thr substitution of BlaC may be associated with an increased susceptibility of MDR-TB isolates to meropenem in the presence of clavulanate.

LncRNA OIP5-AS1 induces epithelial-to-mesenchymal transition and renal fibrosis in diabetic nephropathy via binding to miR-30c-5p

NIn recent years, the incidence of diabetic nephropathy (DN) is rising, and is one of the most important complications of diabetic patients. In this study, the role and regulatory mechanism of lncRNA OIP5-AS1 in the regulation of DN were investigated. Here, the expressions of lncRNA OIP5-AS1 and miR-30c-5p were detected by RT-qPCR. Western blot analysis was used to detect the protein expression of E-cadherin, N-cadherin, TGF-β1, α-SMA. The relationship between OIP5-AS1 and miR-30c-5p was confirmed by dual luciferase reporter assay. The results showed that the expression of lncRNA OIP5-AS1 was increased in db/db DN mice kidney tissue and high glucose-stimulated HK2 cells. lncRNA OIP5-AS1 promoted epithelial-to-mesenchymal transition (EMT) and renal fibrosis in high glucose-stimulated HK2 cells. In addition, lncRNA OIP5-AS1 directly targets miR-30c-5p, and lncRNA OIP5-AS1 negatively regulated miR-30c-5p expression in high glucose-stimulated HK2 cells. More importantly, overexpression of miR-30c-5p attenuated the promoting effect of OIP5-AS1 on EMT and renal fibrosis in high glucose-stimulated HK2 cells. In conclusion, lncRNA OIP5-AS1 induces EMT and renal fibrosis in DN via binding to miR-30c-5p.

Construction of a cDNA library and preliminary analysis of the expressed sequence tags of the earthworm Eisenia fetida (Savigny, 1826)

Earthworms are useful indicator organisms of soil health and Eisenia fetida have been extensively used as test organisms in ecotoxicological studies. In order to gain insight into the gene expression profiles associated with physiological functions of earthworms, a full-length enriched cDNA library of the Eisenia fetida genome was successfully constructed using Switching Mechanism at 5′End of RNA Template technology. Construction of a cDNA library and analysis of Expressed Sequence Tags (ESTs) are efficient approaches for collecting genomic information and identifying genes important for a given biological process. Furthermore, analysis of the expression abundance of ESTs was performed with the aim of providing genetic and transcriptomic information on the development and regenerative process of earthworms. Phrep and Crossmatch were used to process EST data and a total of 1,140 high-quality EST sequences were determined by sequencing random cDNA clones from the library. Clustering analysis of sequences revealed a total of 593 unique sequences including 225 contiguous and 368 singleton sequences. Basic Local Alignment Search Tool analysis against the Kyoto Encyclopedia of Genes and Genomes database resulted in 593 significant hits (P-value <1×10⁻⁸), of which 168 were annotated through Gene Ontology analysis. The STRING database was used to determine relationships among the 168 ESTs, identifying associated genes involved in protein-protein interactions and gene expression regulation. Based on nucleic acid and protein sequence homology, the mutual relationships between 287 genes could be obtained, which identified a portion of the ESTs as known genes. The present study reports on the construction of a high-quality cDNA library representative of adult earthworms, on a preliminary analysis of ESTs and on a putative functional analysis of ESTs. The present study is expected to enhance our understanding of the molecular basis underlying the biological development of earthworms.

Remission effect of vitamin C on isoflurane-induced apoptosis and its mechanism

This study aims to discuss the remission effect of vitamin C on isoflurane-induced apoptosis of rats and its possible mechanism of action, to provide a theoretical basis for postoperative cognitive impairment. Reactive oxygen species (ROS) detection, adenosine triphosphate (ATP) test, MTT method and Morris water maze were applied for detection tests. For data statistics, double factor analysis of variance (ANOVA) and post hoc Bonferroni test were adopted. It was found that vitamin C could slow down the isoflurane-induced accumulation of ROS in H4-APP cells; moreover, it could relieve the activation of caspase-3 and increase cell survival rate to inhibit the occurrence of apoptosis, indicating that ROS was the source of cell toxicity. On the other hand, vitamin C could protect the cells with its antioxidant effect. It was proved that vitamin C could remit isoflurane-induced apoptosis and relieve the decline in learning and memory ability of rats.

[Characteristics of long-term non-progressors and HIV controllers among HIV-infections in Henan, China]

OBJECTIVE

To study the prevalence and characteristics of long-term non-progressors (LTNPs) and HIV controllers (HCs) among HIV-infections in Henan, China.

METHODS

Data in two databases (Information management system of HIV/AIDS prevention and control; HIV/AIDS testing application platform of Henan) were used to identify the LTNPs and HCs, investigation and verification, sample collection and correlation testing were carried out thereafter.

RESULTS

A total of 148 LTNPs/HCs were identified. Among them, 71 were followed up, including 58 LTNPs and 22 HCs, 12 cases were both LTNP and HC, 46 cases were LTNP but non-HC(LTNP+ HC-), 10 cases of HC but non-LTNP. Of the 71 individuals, 50 (70.4%) were males, 55 (77.5%) were older than 40 years of age, all belonged to Han nationality, 61 (85.9%) were farmers, 52 (73.2%) were infected through former plasma donation, 56 (78.9%) were-HCV positive. Median (interquartile range) of the CD4 counts was 538 (445-654) cell/μl and with virus load as 3.14 (2.03-3.82) log(10) copies/ml. The median viral load of HC was lower than that of LTNP + HC-(P=0.001).

CONCLUSION

The characteristic of LTNPs and HCs in Henan HIV-infections were remarkable, more accurate classification of these cases was helpful to further research.

IL-6 gene promoter polymorphisms and risk of coronary artery disease in a Chinese population

We investigated the relationships between single nucleotide polymorphisms (SNPs) of the interleukin (IL)-6 gene 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) and coronary artery disease (CAD) risk in a Chinese population. This case-control study recruited 296 CAD patients and 327 controls between January 2009 and May 2012. Genotyping of IL-6 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) was performed on a 384-well plate format using the Sequenom MassARRAY platform. CAD patients were more likely to be older and male, with a higher body mass index, diabetes, and hypertension, and presented higher triglycerides, and lower total cholesterol, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol. We found that the IL-6 174CC genotype was associated with a significantly increased risk of CAD compared to the wild-type GG genotype in a codominant model [odds ratio (95% confidence interval) = 1.94 (1.13-3.37)], whereas IL-6 174 G>C polymorphisms presented an increased risk of CAD in dominant and recessive models. However, we did not find that the IL-6 572 CC and 597 AA genotypes were correlated with an increased risk of CAD. IL-6 174 G>C rs1800795 was associated with CAD risk in a Chinese population. Further large-scale studies are required to determine whether IL-6 SNPs interact with environmental factors in the development of CAD.

Adsorption and oxidation of ethanol on colloid-based Pt/C, PtRu/C and Pt3Sn/C catalysts: In situ FTIR spectroscopy and on-line DEMS studies

The interaction of colloid-based, carbon supported Pt/C (40 wt%), PtRu/C (45 wt%) and Pt3Sn/C (24 wt%) catalysts with ethanol and their performance for ethanol electrooxidation were investigated in model studies by electrochemical, in situ infrared spectroscopy and on-line differential electrochemical mass spectrometry measurements. The combined application of in situ spectroscopic techniques on realistic catalysts and under realistic reaction (DEMS, IR) and transport conditions (DEMS) yields new insight on mechanistic details of the reaction on these catalysts under the above reaction and transport conditions. Based on these results, the addition of Sn or Ru, though beneficial for the overall activity for ethanol oxidation, does not enhance the activity for C-C bond breaking. Dissociative adsorption of ethanol to form CO2 is more facile on the Pt/C catalyst than on PtRu/C and Pt3Sn/C catalysts within the potential range of technical interests (<0.6 V), but Pt/C is rapidly blocked by an inhibiting CO adlayer. In all cases acetaldehyde and acetic acid are dominant products, CO2 formation contributes less than 2% to the total current. The higher ethanol oxidation current density on the Pt3Sn/C catalyst at these potentials results from higher yields of C2 products, not from an improved complete ethanol oxidation to CO2.

[Study of apoptosis and expression of apoptotic related genes P53 bcl-2 C-myc in oral lichen planus]

OBJECTIVE

To investigate the difference of apoptosis and expression of apoptotic related genes p53 bcl-2 C-myc in the development of oral lichen planus(OLP).

METHODS

Apoptotic cells were detected by TUNEL and immunohistochemical method was used to study P53 bcl-2 C-myc expression in 45 samples with OLP(23 cases of erosive OLP group and 22 cases of non erosive OLP group).

RESULTS

Apoptosis occurred in 100% of the cases and apoptotic index(AI) was 24.3%+/-12.0% (1.9%-50.5%). AI of erosive OLP group was 19.0%+/-10.4% (1.9%-50.5%), and AI of non erosive OLP was 29.4%+/-11.2% (10.4%-49.3%). The obvious differences existed between erosive group and non erosive group (P<0.05). The expression of p53 bcl-2 C-myc positive rates were 31.1% 35.5% 33.3% respectively. The p53 bcl-2 C-myc positive rates in erosive OLP group were 39.1% 52.2% 43.2%and that with non-erosive OLP group were 22.7% 18.2% 22.7% respectively. There was only statistically significance between erosive group and non-erosive group (P<0.05) in expression of bcl-2.

CONCLUSION

Apoptosis and apoptotic related genes p53 bcl-2 C-myc participate in clinical development of OLP. The changes of AI are related to the chronic inflammation of lesion with OLP. We should attach importance to over expression of bcl-2 in erosive OLP.

Human papillomavirus and p53 protein immunoreactivity in condylomata acuminatum and squamous cell carcinoma of penis

AIM

To determine the immunoreactive pattern of human papillomavirus (HPV) antigen and p53 protein in condylomata acuminatum (CA) and squamous cell carcinoma (SCC) of penis.

METHODS

Immunohistochemistry for HPV and p53 were performed in 40 specimens of formalin fixed, paraffin embedded tissues using a polyclonal (rabbit) antibody against HPV and a monoclonal (mouse) antibody against human p53 protein. Twenty one cases of CA and nineteen cases of SCC were examined.

RESULTS

HPV antigen was detected in all 21 CA and 2 penile SCC. p53 protein overexpression was observed in 12 of 19 (63%) SCC in which 6 cases were strong positive. Five of 21 CA (24%) showed low-grade p53 protein overexpression.

CONCLUSION

CA is related to HPV infection and some cases show p53 protein low-grade overexpression. In contrast, p53 protein overexpression is common in penile SCC, which is seldom related to HPV infection.

[Effects of intraventricular injection of adenosine on renal sympathetic nerve activity]

The effects of intraventricular injection of adenosine and its analogues on renal sympathetic nerve activity (RSNA) were examined in sinoaortic denervated and vagotomized anesthetized rats. In response to intraventricular bolus injection of adenosine, RSNA was increased by 41.9 +/- 6.08% (P < 0.001), mean arterial pressure (MAP) was initially increased by 1.39 +/- 0.19 kPa (P < 0.001) and subsequently decreased by 3.74 +/- 0.64 kPa (P < 0.001), and heart rate (HR) was reduced by 95 +/- 14 bpm (P < 0.001). To determine the adenosine-receptor subtype which mediates the response of RSNA to adenosine, we used selective A1-receptor agonist (R-PIA) and A2-receptor agonist (NECA) and found that MAP and HR were reduced by R-PIA and NECA. The effects lasted significantly longer than those of adenosine. R-PIA induced an increase in RSNA by 31.6 +/- 5.21% (P < 0.001), while NECA showed no effect on RSNA. The renal sympathoexcitatory response to intraventricular injection of adenosine was completely inhibited by pretreatment with a selective A1-receptor antagonist (DPCPX). Following the bilateral stellate ganglionectomy, intraventricular injection of adenosine failed to induce the increase in RSNA. The results indicate that adenosine may activate cardiac sympathetic afferents through A1-receptor, resulting in a reflex augmentation of RSNA.

[Endothelin and ATP-sensitive potassium channel mediate electrophysiological changes induced by hypoxia in rabbit sinoatrial node]

The role of ET and KATP channel in hypoxia-induced negative chronotropic effect of pacemaker cells in rabbit sinoatrial node was studied with intracellular microelectrode technique. The results obtained were as follows: (1) Hypoxia produced a progressive decrease in the velocity of diastolic depolarization (VDD) of pacemaker cells resulting in a reduced rate of pacemaker firing (RPF), and induced a decrease in APD, especially APD50. (2) KATP channel opener cromakalim markedly induced a negative chronotropic effect in a concentration-dependent manner and significantly shortened APD50. KATP channel blocker glibenclamide alleviated the effects of hypoxia on pacemaker cells, thereby suggesting the involvement of KATP channel in the hypoxia-induced effects. (3) By superfusion of ET-1, the hypoxia-induced decrease in RPF was remarkably potentiated and the occurrence of pacemaker arrest was shifted to an earlier time. The hypoxia-induced effects could be effectively attenuated after pretreatment with BQ-123, implying the role of endogenous ET-1 release in hypoxia-induced effects. It is concluded that the negative chronotropic effect and the decrease in APD induced by hypoxia may be attributed to the activation of KATP channel and the release of endogenous ET.

[Clinicopathological study of combined preoperative radiotherapy with intracavitary hyperthermia in rectal cancer]

118 specimens of rectal cancer were studied pathologically. 40 cases were treated by both preoperative radiotherapy and intracavitary hyperthermia (group 1), 38 treated by preoperative radiotherapy alone (group 2) and 40 by operation alone (group 3). The tumor disappearance rates by gross observation were 57.5% and 5.3% in groups 1 and 2 (P less than 0.001). The moderate to severe damage of cancer cells (X2-X4) was observed in 90% of cases in group 1 and 31.6% in group 2 (P less than 0.05). In the former, the cancer cell disappearance was observed in 8 cases, while in the latter, only 1 case. The cell degenerations by 30 Gy plus hyperthermia were similar to those by 40 Gy plus hyperthermia, but both were more marked than by 30 Gy alone or 40 Gy alone (P less than 0.05). The lymphocyte, plasma cell infiltration and hyperplasia of fibrous tissue around the tumor in group 1 were more marked than those in groups 2 and 3 (P less than 0.05). The thrombosis around the tumor was more in group 1 than in group 2 (P less than 0.01). Every histological type of the tumor was sensitive to radiotherapy combined with hyperthermia. The lymph node metastatic rates were 35% in group 1 and 31.6% in group 2, both being lower than that in group 3 (52.5%). Immune function of the lymph nodes and the damage of the normal tissues around the tumor are observed. It has been clinically confirmed that neither resection rate is influenced nor postoperative complications are increased by preoperative radiotherapy combined with hyperthermia.