Extracellular vesicles of pathogenic microorganisms: friend or foe? / 中华检验医学杂志

Extracellular vesicles (EV) are lipid bilayer vesicles with a diameter of 30-1000 nm secreted by cells or microorganisms, which are abundant in proteins, nucleic acids, lipids and other biological information molecules. Therefore, EV can be used as a carrier, transferring materials between cells. At present, in infectious diseases, EV derived from pathogenic microorganisms could be considered as a double-edged sword, which means it can not only play a negative role in the host′s infection immunity, bacteria′s pathogenicity and antibiotic resistance transmission, but also manifest the advantages in clinical diagnosis and treatment.

Establishment and clinical performance evaluation of 2019 novel coronavirus antibody colloidal gold detection method / 中华传染病杂志

Objective@#To establish a colloidal gold technique assay for the rapid detection of immunoglobulin(Ig) M and IgG antibodies against 2019 novel coronavirus (2019-nCoV) and to evaluate its clinical performance.@*Methods@#A total of 278 patients who were treated at Wuhan Hankou Hospital and the People's Hospital of Honghu from February 12, 2020 to February 20, 2020 were collected. According to the diagnostic criteria, 89 patients were confirmed with 2019-nCoV nucleic acid positive diagnosis, and 189 were 2019-nCoV nucleic acid-negative suspected patients. A total of 273 medical examiners from Nanfang Hospital, Southern Medical University from 2015 to 2018 were selected as controls. The serum samples of patients were collected. 2019-nCoV nucleic proteins were obtained from prokaryotic expression vectors. Indirect IgM and IgG colloidal gold techniques were established by using recombinant N protein. 2019-nCoV nucleic acid detection by reverse transcription-polymerase chain reaction (RT-PCR) was used as control. Serum specimens were tested for 2019-nCoV IgM and IgG. The specificity and sensitivity of colloidal gold assay were analyzed.@*Results@#The sensitivity and specificity of IgM detection reagents were 78.7% and 98.2%, respectively, those of IgG detection reagents were 73.0% and 99.3%, respectively, and those of IgM combined with IgG detection were 87.6% and 98.2%, respectively. For suspected patients with negative 2019-nCoV nucleic acid, the positive rates of IgM and IgG were 59.8% (113/189) and 52.9% (100/189), respectively, and the positive rate of IgM combined with IgG detection was 66.1% (125/189).@*Conclusion@#This reagent of 2019-nCoV antibodies detection (colloidal gold technique) fulfills the requirement for clinical application with high specificity and sensitivity, which can be served as a supplementary detection method for 2019-nCoV nucleic acid detection by RT-PCR.

Identification and antibiotics sensitivity analysis of Herbaspirillum huttiense in catheter-related bloodstream infection / 中华检验医学杂志

Objective:To analyze the identification and antibiotics susceptibility of Herbaspirillum in catheter-related bloodstream infection, and improve the awareness and attention of the rare pathogenic microorganisms for clinicians and microbiologists. Methods:The bacterium was isolated from a positive blood culture of a hemodialysis patient with chronic renal failure. The smear of isolate was prepared, stained and observed by microscope. The single colonies were identified by mass spectrometry and VITEK 2 Compact identification and antibiotics sensitivity analysis system, respectively. Then, 16S ribosomal DNA (rDNA) was amplified and sequenced, and bacterial genome was sequenced.Results:The gram-negative bacilli was found in the positive blood culture bottle. After incubated on blood agar for 16 hours, milky white, bulging and non-haemolytic colonies were observed. The identification result was Burkholderia cepacian by VITEK 2_Compact and antimicrobial susceptibility testing showed resistance to aztreonam and polymyxin but sensitive to other drugs in N335 card. The isolate could not be identified by VITEK MS with clinical database. However, it was identified as Herbaspirillum huttiense/Herbaspirillum aquaticum with research database. The 16S rDNA of the strain was consistent with Herbaspirillum huttiense and Herbaspirillum aquaticum (more than 99%). High-throughput bacterial genome sequencing revealed that the isolate in this case shared 100% homology with Herbaspirillum huttiense subsp putei IAM 15032 in Genbank database, which confirmed that the isolate was Herbaspirillum huttiense. Conclusions:There are more and more environmental microorganisms evolved into human pathogenic bacteria. Herbaspirillum species are easy to be misidentified because its biochemical characteristics are similar to other strains.

Establishment and clinical performance evaluation of 2019 novel coronavirus antibody colloidal gold detection method / 中华传染病杂志

Objective:To establish a colloidal gold technique assay for the rapid detection of immunoglobulin(Ig)M and IgG antibodies against 2019 novel coronavirus (2019-nCoV) and to evaluate its clinical performance.Methods:A total of 278 patients who were respectively treated at Wuhan Hankou Hospital and the People′s Hospital of Honghu from February 12, 2020 to February 20, 2020 were collected. According to the diagnostic criteria, 89 patients were confirmed with positive 2019-nCoV nucleic acid, and 189 were 2019-nCoV nucleic acid-negative suspected patients. A total of 273 medical examiners from Nanfang Hospital, Southern Medical University from 2015 to 2018 were selected as controls. The serum samples of patients were collected. 2019-nCoV nucleic proteins were obtained from prokaryotic expression vectors. Indirect IgM and IgG colloidal gold techniques were established by using recombinant nuclear protein. 2019-nCoV nucleic acid detection by reverse transcription-polymerase chain reaction (RT-PCR) was used as control. Serum specimens were tested for 2019-nCoV IgM and IgG. The specificity and sensitivity of colloidal gold assay were analyzed.Results:The positive rates of IgM and IgG with the colloidal gold detection in confirmed patients with positive 2019-nCoV nucleic acid were 78.7%(70/89) and 73.0%(65/89), respectively. The positive rates of IgM and IgG in medical examiners were 1.8%(5/273) and 0.7%(2/273), respectively. The sensitivity and specificity of IgM detection reagents were 78.7% and 98.2%, respectively, those of IgG detection reagents were 73.0% and 99.3%, respectively, and those of IgM combined with IgG detection were 87.6% and 98.2%, respectively. For suspected patients with negative 2019-nCoV nucleic acid, the positive rates of IgM and IgG were 59.8%(113/189) and 52.9%(100/189), respectively, and the positive rate of IgM combined with IgG detection was 66.1%(125/189).Conclusion:This reagent of 2019-nCoV antibodies detection (colloidal gold technique) fulfills the requirement for clinical application with high specificity and sensitivity, which can be served as a supplementary detection method for 2019-nCoV nucleic acid detection by RT-PCR.

Morphologic features suggestive of submucosal invasive adenocarcinoma in colorectal mucosal biopsy specimens / 中华病理学杂志

<p><b>OBJECTIVE</b>To observe and summarize the morphologic features that may suggest submucosal invasive adenocarcinoma in colorectal mucosa biopsy specimens.</p><p><b>METHODS</b>The study cohort included 432 colorectal biopsy specimens were obtained from 2006 to 2012. All the cases had radical surgery. Basing on the pathologic diagnoses, the cases were divided into 366 invasive adenocarcinoma (IAC) and 66 high-grade intraepithelial neoplasms (HGIN). These two groups were compared.</p><p><b>RESULTS</b>In the IAC group, the percentage of tumor forming cribriform structures, acute angle-shaped glands, diffuse carcinoma cell proliferation was 61.2% (224/366) , 33.8% (124/366) and 7.4% (27/366) , respectively. In the HGIN group, cribriform gland structures appeared in 6.0% (4/66) of the cases, while no acute angle-shaped gland or diffuse carcinoma cell proliferation was detected. The difference of these three characteristics in the two group was statistically significant (all P < 0.01). Glandular branching was detected in 89.9% (329/366) of IAC cases and 66.7% (44/66) of HGIN cases; this difference was not significant. There was no difference in cellular atypia between the two groups. Interstitial fibrosis was detected more frequently in the IAC group (85.5%, 313/366 in IAC versus 0 in HGIN, P < 0.01). In biopsy specimens of IAC, a few cases showed neoplastic glands in close contact with large lymphatics, adipose tissue, and ganglion.</p><p><b>CONCLUSIONS</b>In colorectal biopsy specimen, the five features that suggest submucosal invasion of the neoplastic glands including the formation of cribriform structure, angular gland, diffuse carcinoma cells, interstitial fibrosis and neoplastic glands in close contact with the thick-walled vessels.</p>

Expression of serum microRNA-192 in the diabetic nephropathy patients and its impact on TGF-β signaling pathway / 中华肾脏病杂志

Objective To detect the expression of serum microRNA (miR)-192 in diabetic nephropathy (DN) patients and investigate its effects on DN. Methods The serum levels of miR-192 and miR-210 in DN patients,diabetic patients without renal injury and healthy people were detected by real-time quantitative PCR.Down-stream target genes were predicted using TargetScan software and further confirmed by gain of function and loss of function studies in vitro.Mesangial cells were treated with different concentrations of TGF-β1,then miR-192 expressions of cells and supernatant were examined as well. Results Serum miR-192 level significantly decreased in DN patients compared with healthy people (0.41 ±0.09 vs 1.00±0.00,P＜0.01) and diabetic patients without renal injury,while the serum miR-210 levels were not significantly different among three groups.Bioinformatics analysis results showed that some target genes were involved in TGF-β signal pathway.ZBP1,IGF-1 and type Ⅰ collagen (Col Ⅰ ) were chosen and confirmed by Western blotting,which were regulated by miR-192.TGF-β1 decreased the expression of miR-192 in both cells and cell culture supematants. Conclusion Serum miR-192 may promote the progress of DN by regulating TGF-β1 signaling pathway and may be used as a potential biomarker in the diagnosis of DN depending on its certain specificity.

Effects of keto-valine-calcium and keto-isoleucine-calcium on proliferation of human mesangial cells and its mechanism study / 中国医师杂志

Objective To study the effects of keto-valine-calcium and keto-isoleucine-calcium on(human mesangial cells)HMCs. Method HMCs were stimulated by keto-valine-calcium and keto-isoleucine-calcium. The AT1R and TGF-β1 were detected. MTr method was used to measure the proliferation of HMCs, and cell cycle was studied by flow cytometry. Results The expression of AT1R and TGF-β1was increased in the experiment groups compared with negative and DMSO control groups. Cell cycle G1 attest and cell apoptosis were observed in the experiment groups. Conclusions 10mM keto-valine-calcium and keto-isoleueine-calcium have multiple effects on HMCs in vitro, which not only increased the expression of AT1R,but also the expression of TGF-β1.Furthermore,keto-valine-calcium and keto-isoleucine-calcium can induce cell cycle G1 arrest and cell apoptosis.