BACKGROUND

Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.

To determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.

We performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.

We found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.

Our analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.

BACKGROUND

Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.

To determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.

We performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.

We found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.

Our analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.

BACKGROUND: Drug resistance is the main cause of high mortality of lung cancer. This study was conducted to investigate the effect of folic acid (FA) on the resistance of non-small cell lung cancer (NSCLC) cells to Osimertinib (OSM) by regulating the methylation of dual specificity phosphatase 1 (DUSP1). METHODS: The OSM resistant NSCLC cell line PC9R was establishd by gradually escalation of OSM concentration in PC9 cells. PC9R cells were randomly grouped into Control group, OSM group (5 μmol/L OSM), FA group (600 nmol/L FA), methylation inhibitor decitabine (DAC) group (10 μmol/L DAC), FA+OSM group (600 nmol/L FA+5 μmol/L OSM), and FA+OSM+DAC group (600 nmol/L FA+5 μmol/L OSM+10 μmol/L DAC). CCK-8 method was applied to detect cell proliferation ability. Scratch test was applied to test the ability of cell migration. Transwell assay was applied to detect cell invasion ability. Flow cytometry was applied to measure and analyze the apoptosis rate of cells in each group. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) method was applied to detect the expression level of DUSP1 mRNA in cells. Methylation specific PCR (MSP) was applied to detect the methylation status of the DUSP1 promoter region in each group. Western blot was applied to analyze the expression levels of DUSP1 protein and key proteins in the DUSP1 downstream mitogen-activated protein kinase (MAPK) signaling pathway in each group. RESULTS: Compared with the Control group, the cell OD450 values (48 h, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the OSM group were obviously decreased (P<0.05); the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of extracellular regulated protein kinases (ERK) were obviously increased (P<0.05); the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the DAC group were obviously increased (P<0.05); the apoptosis rate, the expression of p38 MAPK protein, the phosphorylation level of ERK, and the methylation level of DUSP1 were obviously reduced (P<0.05). Compared with the OSM group, the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the FA+OSM group were obviously decreased (P<0.05); the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of ERK were obviously increased (P<0.05). Compared with the FA+OSM group, the cell OD450 values (48, 72 h), scratch healing rate, number of cell invasions, and expression of DUSP1 in the FA+OSM+DAC group were obviously increased; the apoptosis rate, the methylation level of DUSP1, the expression of p38 MAPK protein, and the phosphorylation level of ERK were obviously reduced (P<0.05). CONCLUSIONS FA may inhibit DUSP1 expression by enhancing DUSP1 methylation, regulate downstream MAPK signal pathway, then promote apoptosis, inhibit cell invasion and metastasis, and ultimately reduce OSM resistance in NSCLC cells.
Humans ; Carcinoma, Non-Small-Cell Lung/genetics* ; Lung Neoplasms/genetics* ; Dual Specificity Phosphatase 1/pharmacology* ; Cell Proliferation ; p38 Mitogen-Activated Protein Kinases/pharmacology* ; Methylation ; Apoptosis ; Cell Line, Tumor

BACKGROUND: Screening using low-dose computed tomography (LDCT) is a more effective approach and has the potential to detect lung cancer more accurately. We aimed to conduct a meta-analysis to estimate the accuracy of population-based screening studies primarily assessing baseline LDCT screening for lung cancer. METHODS: MEDLINE, Excerpta Medica Database, and Web of Science were searched for articles published up to April 10, 2022. According to the inclusion and exclusion criteria, the data of true positives, false-positives, false negatives, and true negatives in the screening test were extracted. Quality Assessment of Diagnostic Accuracy Studies-2 was used to evaluate the quality of the literature. A bivariate random effects model was used to estimate pooled sensitivity and specificity. The area under the curve (AUC) was calculated by using hierarchical summary receiver-operating characteristics analysis. Heterogeneity between studies was measured using the Higgins I2 statistic, and publication bias was evaluated using a Deeks' funnel plot and linear regression test. RESULTS: A total of 49 studies with 157,762 individuals were identified for the final qualitative synthesis; most of them were from Europe and America (38 studies), ten were from Asia, and one was from Oceania. The recruitment period was 1992 to 2018, and most of the subjects were 40 to 75 years old. The analysis showed that the AUC of lung cancer screening by LDCT was 0.98 (95% CI: 0.96-0.99), and the overall sensitivity and specificity were 0.97 (95% CI: 0.94-0.98) and 0.87 (95% CI: 0.82-0.91), respectively. The funnel plot and test results showed that there was no significant publication bias among the included studies. CONCLUSIONS Baseline LDCT has high sensitivity and specificity as a screening technique for lung cancer. However, long-term follow-up of the whole study population (including those with a negative baseline screening result) should be performed to enhance the accuracy of LDCT screening.
Humans ; Adult ; Middle Aged ; Aged ; Lung Neoplasms/diagnostic imaging* ; Early Detection of Cancer ; Sensitivity and Specificity ; Mass Screening ; Tomography, X-Ray Computed

Humans ; Biopsy, Fine-Needle ; Consensus ; Thyroid Neoplasms/pathology* ; Thyroid Nodule/pathology* ; Sensitivity and Specificity

Humans ; Pregnancy ; Female ; Culture Media ; Pregnancy Complications, Infectious ; Sensitivity and Specificity

c-Myc protein encoded by c-Myc (cellular-myelocytomatosis viral oncogene) gene regulates the related gene expression through the Wnt/β-catenin signaling pathway, and has received extensive attention in recent years. The purpose of this study was to express Helicoverpa armigera c-Myc gene (Ha-c-Myc) by using prokaryotic expression system, prepare the polyclonal antibody, examine the spatio-temporal expression profile of Ha-c-Myc, and investigate the possible function of Ha-c-Myc in regulating H. armigera sterol carrier protein-2 (SCP-2) gene expression. The Ha-c-Myc gene was amplified by PCR and cloned into a prokaryotic expression plasmid pET-32a(+). The recombinant plasmid pET-32a-Ha-c-Myc was transformed into Escherichia coli BL21. IPTG was used to induce the expression of the recombinant protein. Protein was purified by Ni²⁺-NTA column and used to immunize New Zealand rabbits for preparing the polyclonal antibody. The Ha-c-Myc expression levels in different developmental stages (egg, larva, prepupa, pupa, and adult) of H. armigera and different tissues (midgut, fat body, head, and epidermis) of the prepupa were determined by real-time quantitative reverse transcription PCR (qRT-PCR). Ha-c-Myc siRNA was synthesized and transfected into H. armigera Ha cells. The relative mRNA levels of Ha-c-Myc and HaSCP-2 in Ha cells were detected by qRT-PCR. Results showed that the pET-32a-Ha-c-Myc recombinant plasmid was constructed. The soluble Ha-c-Myc protein of about 65 kDa was expressed in E. coli. The polyclonal antibody was prepared. Western blotting analysis suggested that the antibody had high specificity. Enzyme linked immunosorbent assay (ELISA) showed that the titer of the antibody was high. Ha-c-Myc gene expressed at all developmental stages, with high levels in the early and late instars of larva, and the prepupal stage. Tissue expression profiles revealed that Ha-c-Myc expressed in various tissues of prepupa, with high expression level in the midgut, but low levels in the epidermis and fat body. RNAi results showed that the knockdown of Ha-c-Myc expression significantly affected transcription of HaSCP-2, leading to a 50% reduction in HaSCP-2 mRNA expression level. In conclusion, the Ha-c-Myc was expressed through a prokaryotic expression system, and the polyclonal anti-Ha-c-Myc antibody was obtained. Ha-c-Myc may promote the expression of HaSCP-2 and play an important role in the lipid metabolism of H. armigera. These results may facilitate further study on the potential role and function mechanism of Ha-c-Myc in H. armigera and provide experimental data for exploring new targets of green pesticides.
Animals ; Rabbits ; Escherichia coli/metabolism* ; Enzyme-Linked Immunosorbent Assay ; Moths/genetics* ; Blotting, Western ; Larva/genetics* ; Isoantibodies/metabolism* ; Antibody Specificity

Objective To investigate the clinical value of high-frequency ultrasound in the diagnosis of pronator teres syndrome (PTS). Methods The high-frequency ultrasound was employed to examine and measure the median nerve of the pronator teres muscle in 30 patients with PTS and 30 healthy volunteers (control group).The long-axis diameter (LA),short-axis diameter (SA) and cross-sectional area (CSA) of the median nerve were measured.The receiver operating characteristic curve of the median nerve ultrasonic measurement results was established,and the area under the curve (AUC) was calculated.The diagnostic efficiency of each index for PTS was compared with the surgical results as a reference. Results The PTS group showed larger LA[(5.02±0.50) mm vs.(3.89±0.41) mm;t=4.38,P=0.013],SA[(2.55±0.46) mm vs.(1.70±0.41) mm;t=5.19,P=0.009],and CSA[(11.13±3.72) mm² vs.(6.88±2.68) mm²;t=8.42,P=0.008] of the median nerve than the control group.The AUC of CSA,SA,and LA was 94.3% (95%CI=0.912-0.972,Z=3.586,P=0.001),77.7% (95%CI=0.734-0.815,Z=2.855, P=0.006),and 78.8% (95%CI=0.752-0.821,Z=3.091,P=0.004),respectively.With 8.63 mm² as the cutoff value,the sensitivity and specificity of CSA in diagnosing PTS were 93.3% and 90.0%,respectively. Conclusion High-frequency ultrasound is a practical method for diagnosing PTS,and the CSA of median nerve has a high diagnostic value.
Humans ; Forearm/innervation* ; Muscle, Skeletal/innervation* ; Median Nerve/diagnostic imaging* ; Ultrasonography/methods* ; Sensitivity and Specificity

Cardiovascular disease is the leading cause of death worldwide, accounting for 48.0% of all deaths in Europe and 34.3% in the United States. Studies have shown that arterial stiffness takes precedence over vascular structural changes and is therefore considered to be an independent predictor of many cardiovascular diseases. At the same time, the characteristics of Korotkoff signal is related to vascular compliance. The purpose of this study is to explore the feasibility of detecting vascular stiffness based on the characteristics of Korotkoff signal. First, the Korotkoff signals of normal and stiff vessels were collected and preprocessed. Then the scattering features of Korotkoff signal were extracted by wavelet scattering network. Next, the long short-term memory (LSTM) network was established as a classification model to classify the normal and stiff vessels according to the scattering features. Finally, the performance of the classification model was evaluated by some parameters, such as accuracy, sensitivity, and specificity. In this study, 97 cases of Korotkoff signal were collected, including 47 cases from normal vessels and 50 cases from stiff vessels, which were divided into training set and test set according to the ratio of 8 : 2. The accuracy, sensitivity and specificity of the final classification model was 86.4%, 92.3% and 77.8%, respectively. At present, non-invasive screening method for vascular stiffness is very limited. The results of this study show that the characteristics of Korotkoff signal are affected by vascular compliance, and it is feasible to use the characteristics of Korotkoff signal to detect vascular stiffness. This study might be providing a new idea for non-invasive detection of vascular stiffness.
Humans ; Vascular Stiffness ; Neural Networks, Computer ; Cardiovascular Diseases/diagnosis* ; Sensitivity and Specificity

Objective To investigate antigen optimization of Shisa like protein 1 (SHISAL1) for preparing mouse anti-human SHISAL1 polyclonal antibody and to identify the specificity of the prepared antibody. Methods Bioinformatics was employed to predict the antigenic epitope region of SHISAL1 protein, and then a polypeptide composed of amino acid residues from the site of 28 to 97 of SHISAL1, termed SHISAL1-N, was selected as the antigen. The coding region of SHISAL1-N was cloned by molecular cloning technique, and then it was inserted into pET-28a to generate pET28a-SHISAL1-N recombinant plasmid. The two recombinant plasmids pET28a-SHISAL1-N and pET28a-SHISAL1 were transformed into BL21 (DE3) bacteria and induced to express by IPTG. The two proteins were purified and immunized to female Kunming mice, respectively. The specificities and sensitivities of the acquired antibodies were detected by Western blot analysis, immunoprecipitation and immunofluorescent cytochemical staining. Results pET28a-SHISAL1-N recombinant plasmid was successfully constructed, and the two fused proteins, SHISAL1 and SHISAL1-N, were induced to express. Moreover, two types of SHISAL1 mouse polyclonal antibodies, derived from SHISAL1-N and SHISAL1 antigens, were obtained. Western blot results showed that the antibody prepared from SHISAL1 antigen was less specific and sensitive compared with the antibody prepared from SHISAL1-N antigen which could specifically identify different endogenous SHISAL1 protein. Immunoprecipitation results showed that SHISAL1-N antibody could specifically pull down SHIISAL1 protein in hepatocellular carcinoma cells and immunofluorescence results demonstrated that SHISAL1-N antibody could specifically bind to SHISAL1 protein in the cytoplasm. Conclusion We have optimized the SHISAL1 antigen and prepared the mouse anti-human SHISAL1 polyclonal antibodies successfully, which can be used for Western blot analysis, immunoprecipitation and immunofluorescence cytochemical staining.
Animals ; Female ; Humans ; Mice ; Antibodies ; Antibody Specificity ; Blotting, Western ; Cloning, Molecular ; Epitopes/genetics*