Frontiers in Laboratory Medicine最新文献

Background

Helicobacter pylori infection remains a major risk for gastroduodenal inflammation and ulceration with capability to disrupt the defensive autophagy pathway in the gastric mucosal cell thus producing resilient infection. A single-nucleotide mutation in the autophagy gene ATG16L1 which controls the host immune responses to viruses and bacteria was identified as a risk factor for increasing survival and persistence of many microbial infections.

Aim

To assess the association of ATG16L1 T300A gene mutation with the susceptibility to H. pylori infection in patients with chronic gastritis disease.

Methods

ATG16L1 T300A mutation was determined by TaqMan genotyping allele specific discrimination real-time PCR assay applying specific primers, (rs2241880 A/G) and probes for A and G allele.

Result

Patients with mutant homozygous GG genotype was associated with a 4.5 times increase in the risk of H. pylori infection relative to the wild homozygous AA and the heterozygous AG genotypes (p value = 0.009, OR = 4.472; 95% CI, 0.07–0.74). The carriage rate of the mutant G allele was significantly higher in H. pylori positive cases (64%) relative to (42%) in H. pylori negative cases (p value = 0.002, OR = 2.455, 95% CI, 0.3 (0.09–1.01), and this was associated with about a 2.5 times increase in the risk for H. pylori infection.

Conclusion

Genetic variant ATG16L1 T300A mutation increased the risk of H. pylori infection in Egyptian patients with chronic gastritis disease.

Objective

Differential expression profiles of free microRNAs (miRNAs) in cerebrospinal fluid (CSF) from patients with intracerebral haemorrhage (ICH) and controls were analysed to identify miRNA markers associated with ICH-induced brain injury.

Methods

Five patients with acute ICH were enrolled alongside five control inpatients without CNS diseases. CSF specimens were collected during initial lumbar puncture after admission, total free RNAs were extracted from CSF, and miRNAs were detected by Agilent Human miRNA V21.0 chip experiments. Differential expression profiles were statistically analysed.

Results

Principal component analysis of miRNA microarray data confirmed that case and control groups were distinct, and biological repeats were homogeneous. After normalisation of chip data, differential miRNAs were screened using fold change and Student's t-tests; 77 miRNAs were up-regulated (fold change > 2), and 44 miRNAs were down-regulated (fold change < 0.5).

Conclusion

ICH patients display distinct miRNA expression profiles in CSF, suggesting that miRNAs may be auxiliary diagnostic biomarkers for ICH.

Terahertz (THz = 10¹² Hz) radiation has caused enormous widespread attention due to its use in biomedical sciences. The tremendous advances in THz instruments have made an impressive breakthrough in biomedical research. The absorption of THz radiation in molecular and bimolecular systems is primarily stimulated by intramolecular and intermolecular vibrations because it is situated between infrared light and microwave radiation. In this paper, we summarized recent research achievements in THz spectroscopy in detecting biological macromolecules such as amino acids, peptides, proteins, nucleic acids and carbohydrates. And the biosafety of this technique has also been discussed. In the end, we discussed the potential biological effects of THz radiation in the biological application and depicted the prospects of this cutting-edge technology.

The study aims to investigate the protective immunity against Echinococcus granulosus in mice immunized with14-3-3–MPLA–liposome vaccine. ICR (Institute of Cancer Research) mice were subcutaneously immunized three times with 14-3-3–MPLA–liposome vaccine, followed by the challenge with Echinococcus granulosus protoscoleces intraperitoneally and then sacrificed after six months of post-challenge. The levels of IL-4, and IFN-γ were measured by ELISA. The rate of reduced hydatid cyst and the levels of IgE, IgG and IgG subclasses in sera were examined. The result showed that mice vaccinated with14-3-3–MPLA–liposome vaccine and challenged with protoscoleces revealed significant protective immunity of 95.07%. ELISA analysis indicated that the immunized mice generated specific high levels of IgG and the prevailing isotypes of IgG were IgG1 and IgG2a. The level of IFN-γ increased significantly in the vaccinated mice whereas there was no significant difference in IL-4 levels between vaccinated and control mice. It is concluded that the14-3-3–MPLA–liposome vaccine could induce a high level of protective immunity to prevent cystic echinococcosis. The MPLA and liposome are promising vaccine adjuvant and delivery system.

HER2 amplification detection assays are widely used as companion diagnostic tools for Herceptin targeted therapy on Breast and Gastric cancer patients. Current tests approved for clinical use are in general IHC or FISH-based and could only be used on tissue samples. This requires tissue processing to generate FFPE slices and subjective results determination by pathologists. Here we report the development and validation of a digital PCR based assay to be used to determine the status of HER2 amplification in both tissue and plasma samples. Interestingly, we have found that the status of HER2 may change during therapy and disease development, supporting the necessity of a liquid biopsy assay for HER2 amplification.

Antiphospholipid syndrome (APS) is an autoimmune disease with manifestations of recurrent thromboembolic events, unexplained miscarriage, and thrombocytopenia. Although the presence of one or more types of antiphospholipid antibodies (aPLs) in serum is accepted, the specific pathogenesis of APS is still unknown. In recent years, some newly found mechanisms of APS progression have been elucidated. Meanwhile more attention is paid to exploring other antibodies rather than aPLs. The aim of this review is to summarize some cellular and molecular mechanisms relevant to APS, and to point out several more meaningful indicators for APS diagnosis or thrombosis prediction compared to aPL.

Background

Most hepatitis E virus (HEV) infections are mild or subclinical, however, the infections are characteristically associated with a high incidence of symptomatic presentation among pregnant women.

Objectives

The aim of this study was to assess the HEV prevalence among pregnant women in Zhenjiang, China.

Materials and methods

225 and 208 of serum samples collected from pregnant and healthy nonpregnant women, respectively, were used to detect anti-HEV IgG and IgM levels. IgM positive samples were further tested for HEV RNA by using RT-nested PCR (nPCR) method. Positive PCR products were sequenced and subjected to phylogenetic analysis.

Results

21.8% (49/225) of samples were anti-HEV IgG positive in pregnant women, whereas 7.7% (16/208) of samples were anti-HEV IgG positive in control subjects (P < 0.001). With respect to anti-HEV IgM testing, 3.6% (8/225) and 0.0% (0/208) were positive in pregnant women and control subjects, respectively (P = 0.006 < 0.01). 4 out of 8 IgM positive samples were positive for HEV RNA. Phylogenetic analysis indicated that four HEV strains had distinct nucleotide sequences and clustered into two different sub-genotypes in genotype 4.

Conclusions

In the current study, the prevalence of HEV infection with respect to IgG and IgM levels among pregnant women was significantly higher than that in the healthy nonpregnant group. Additionally, all four HEV strains belonged to genotype 4 implying that genotype 4 is the predominant genotype in the area.

Objective

Both iron deficiency anemia (IDA) and thalassaemia trait (TT) are indistinguishable in pregnancy. This study aimed to establish some new hematological indices based on erythrocyte and reticulocyte parameters to distinguish each other.

Methods

A total of 425 anemic pregnant women including 177 cases with IDA, 105 cases with α-TT, and 143 cases with β-TT were enrolled in the study and divided into two groups: development and validation groups. Logit-P1 (for identifying TT from IDA) and logit-P2 equations (for distinguishing between α-TT and β-TT) were designed in the development group, and their diagnostic performances were compared with 12 previous hematological indices in the validation group.

Results

The optimal cut-off value, sensitivity, sensitivity of logit-P1 were 0.84, 85.9%, 55.9%, and those of logit-P2 were 0.41, 85.9%, 55.9%. Compared to 12 hematological indices, logit-P1 (AUC = 0.765) and logit-P2 (AUC = 0.919) provided optimal identification performances within respective application ranges (P < 0.001). In combination with the supplementary criteria (RBC#≥4.1 × 10¹²/L), the two equations had low missed diagnosis rate and high accuracy rate for α-TT carriers (6.3% and 79.4%) and β-TT carriers (4.7% and 81.4%), and showed moderate agreement with clinical diagnosis (Kappa = 0.540).

Conclusion

For screening TT in anemic pregnant women, reticulocyte detection should be taken into account. The hematological indices based on erythrocyte and reticulocyte parameters would be superior to those only calculated by erythrocyte parameters.

Background: In our prior study, Bmi-1 was elevated in non-small cell lung cancer (NSCLC) and took an important role in the early stage of progression. However, the clinical significance of Bmi-1 in NSCLC was uncertain. The aim of this study was to illuminate the relationship between Bmi-1, clinical variables and the prognosis of patients with NSCLC. Methods: Real-time PCR was used to examine the expression of Bmi-1 mRNA in 23 paired NSCLC and the adjacent normal tissues. The expression of Bmi-1 protein in 128 specimens of NSCLC was determined by immunohistochemistry assay. Statistical analyses were performed to evaluate the association between the expression of Bmi-1, clinicopathologic features and prognosis. Results: Up-regulated expression of Bmi-1 mRNA was observed in 91.3% of NSCLC (P < 0.0001). The level of Bmi-1 was positively correlated with T stage (P = 0.019), and the 5-year overall survival of patients with higher Bmi-1 level was lower than that of patients with lower Bmi-1 level without statistical significance (P = 0.189). Histological classification and smoking status were not related to prognosis (P = 0.166, 0.615). For patients with adenocarcinoma, lower level of Bmi-1 was related to good prognosis (P = 0.033), and in multivariate analysis, metastasis, T stage and lymph node involvement were independent prognostic factors (P = 0.001, 0.044, 0.013). Conclusions: Expression of Bmi-1 mRNA was higher in NSCLC than in the adjacent normal tissues. The detection of Bmi-1 protein expression is potentially useful in prognostic evaluation of lung adenocarcinoma.

Epidermal growth factor receptor (EGFR) is a crucial factor in the development of non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitor (TKI) therapy requires a sensitive and accurate assay for detection of drug resistant mutations in patients undergoing TKI-based targeted therapy. Digital polymerase chain reaction (PCR) is a highly sensitive PCR based detection method with the capability of absolute quantification. Here we present a digital PCR based liquid biopsy for EGFR T790M detection from blood samples with a low detection limit of 0.1% mutant allele frequency. The assay shows 100% concordance with test results obtained from cFDA approved ARMS PCR based EGFR mutation detection assay on FFPE tissue sections. It also demonstrated satisfactory sensitivity and specificity at 62.5% and 100% respectively. This assay can satisfy the clinical need of detecting EGFR T790M mutations at extremely low allele frequency. It can be used as both a companion diagnostic tool and a monitoring strategy for the development of drug resistance, and to evaluate therapeutic effects on disease progression.