Controllable Fabrication of Highly Ordered Spherical Microcavity Arrays by Replica Molding of In Situ Self-Emulsified Droplets.

Ordered spherical hollow micro- and nanostructures hold great appeal in the fields of cell biology and optics. However, it is extremely challenging for standard lithography techniques to achieve spherical micro-/nanocavities. In this paper, we describe a simple, cost-effective, and scalable approach to fabricate highly ordered spherical microcavity arrays by replica molding of in situ self-emulsified droplets. The in situ self-emulsion involves a two-step process: discontinuous dewetting-induced liquid partition and interfacial tension-driven liquid spherical transformation. Subsequent replica molding of the droplets creates spherical microcavity arrays. The shapes and sizes of the microcavities can be easily modulated by varying the compositions of the droplet templates or utilizing an osmotically driven water permeation. To demonstrate the utility of this method, we employed it to create a spherical microwell array for the mass production of embryoid bodies with high viability and minimal loss. In addition, we also demonstrated the optical functions of the generated spherical microcavities by using them as microlenses. We believe that our proposed method will open exciting avenues in fields ranging from regenerative medicine and microchemistry to optical applications.

Development and application of hepatocellular carcinoma risk prediction model based on clinical characteristics and liver related indexes.

BACKGROUND: Hepatocellular carcinoma (HCC) is difficult to diagnose with poor therapeutic effect, high recurrence rate and has a low survival rate. The survival of patients with HCC is closely related to the stage of diagnosis. At present, no specific serological indicator or method to predict HCC, early diagnosis of HCC remains a challenge, especially in China, where the situation is more severe. AIM: To identify risk factors associated with HCC and establish a risk prediction model based on clinical characteristics and liver-related indicators. METHODS: The clinical data of patients in the Affiliated Hospital of North Sichuan Medical College from 2016 to 2020 were collected, using a retrospective study method. The results of needle biopsy or surgical pathology were used as the grouping criteria for the experimental group and the control group in this study. Based on the time of admission, the cases were divided into training cohort (n = 1739) and validation cohort (n = 467). Using HCC as a dependent variable, the research indicators were incorporated into logistic univariate and multivariate analysis. An HCC risk prediction model, which was called NSMC-HCC model, was then established in training cohort and verified in validation cohort. RESULTS: Logistic univariate analysis showed that, gender, age, alpha-fetoprotein, and protein induced by vitamin K absence or antagonist-II, gamma-glutamyl transferase, aspartate aminotransferase and hepatitis B surface antigen were risk factors for HCC, alanine aminotransferase, total bilirubin and total bile acid were protective factors for HCC. When the cut-off value of the NSMC-HCC model joint prediction was 0.22, the area under receiver operating characteristic curve (AUC) of NSMC-HCC model in HCC diagnosis was 0.960, with sensitivity 94.40% and specificity 95.35% in training cohort, and AUC was 0.966, with sensitivity 90.00% and specificity 94.20% in validation cohort. In early-stage HCC diagnosis, the AUC of NSMC-HCC model was 0.946, with sensitivity 85.93% and specificity 93.62% in training cohort, and AUC was 0.947, with sensitivity 89.10% and specificity 98.49% in validation cohort. CONCLUSION: The newly NSMC-HCC model was an effective risk prediction model in HCC and early-stage HCC diagnosis.

Establishment and application of a survival rate graph model based on biomarkers and imaging indexes after primary hepatocellular carcinoma resection.

BACKGROUND: Primary liver cancer (PLC) is a highly malignant disease. This study developed an effective and convenient tool to evaluate survival times of patients after hepatectomy, which can provide a reference point for clinical decisions. METHODS: Clinical and laboratory data of 243 patients with PLC after hepatectomy were collected. Univariate cox regression analysis, Lasso regression analysis and multivariate cox regression analysis were used to determine the best prediction index. Multivariate cox regression analysis was used to construct a survival prediction model. A receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA) were used to verify the model. The patients in this model were divided into was divided into high-risk and low-risk groups according to the optimal cut-off value of the ROC curve for different prognostic years. Kaplan-Meier survival analysis and log-rank test were used to analyse the survival differences between the two groups. RESULTS: Tumour size, portal vein thrombosis, distant metastasis, alpha-fetoprotein and protein induced by vitamin K absence or antagonist-II levels were independent risk factors for overall survival (OS) after PLC surgery. The area under the concentration-time curve for 2-, 3- and 4-year survival of patients was 0.710, 0.825 and 0.919, respectively, with a good calibration of the Hosmer-Lemeshow test (p > 0.05) and net benefit. The mortality rates in patients with 2, 3 and 4 years of survival were 70.59%, 67.83% and 66.67% for the high-risk group and 21.84%, 22.50% and 22.67% for the low-risk group, respectively. The mortality rate of the high-risk group was significantly higher than that of the low-risk group (p < 0.05). CONCLUSION: The OS model of prognosis after PLC surgery constructed in this study can be used to predict the 2-, 3- and 4-year survival prognoses of patients, and patients with different prognosis years can be re-stratified so that they achieve more accurate and personalised assessment, thereby providing a reference point for clinical decision-making.

Cell spheroids culture array with modifiable chemical gradients.

Cancer cell spheroids have been shown to mimic in vivo tumour microenvironment and are therefore suitable for in vitro drug screening. Microfluidic technology can provide conveniences for spheroid assays such as high-throughput, simplifying manual operation and saving reagent. Here, we propose a concentration gradient generator based on microfluidic technology for cell spheroid culture and assay. The chip consists of upper microchannels and lower microwells. After partitioning HepG2 suspension into the microwells with concave and non-adhesive bottoms, spheroids can spontaneously form. By controlling the fluid replacement and flow in microchannels, the doxorubicin solution is diluted automatically into a series of concentration gradients, which spanning more than one order of magnitude. And then the effect of doxorubicin on spheroids is measured in situ by fluorescent staining. This chip provides a very promising approach to achieve the high-throughput and standardized anti-cancer drug screening in future.

Theoretical and experimental research on two-phase flow image reconstruction and flow pattern recognition.

Two-phase flow is a kind of complex fluid flow state, and the flow pattern characteristics are very difficult to obtain accurately. First, the principle of two-phase flow pattern image reconstruction based on electrical resistance tomography technology and the complex flow pattern recognition method are developed. Next, the back propagation (BP), wavelet, and radial basis function (RBF) neural networks are applied to the two-phase flow pattern image identification process. The results show that the RBF neural network algorithm has higher fidelity and faster convergence speed than the BP and wavelet network algorithms, and the fidelity is more than 80%. Then, deep learning of the pattern recognition algorithm fusing the RBF network and convolution neural network is proposed to improve the precision of the flow pattern identification. Additionally, the recognition accuracy of the fusion recognition algorithm is more than 97%. Finally, a two-phase flow test system is constructed, the test is finished, and the correctness of the theoretical simulation model is verified. The research process and results provide important theoretical guidance for the accurate acquisition of two-phase flow patterns.

Retrospective screening of serum IgG glycosylation biomarker for primary Sjögren's syndrome using lectin microarray.

Background: Primary Sjögren's syndrome (PSS) is a systemic autoimmune disease resulting in significant loss of systemic gland secretory function. IgG glycosylation abnormalities had been found to play important roles in autoimmune diseases. Here, we aim to explore the specific changes of IgG glycosylation in PSS patient serum that could serve as potential biomarkers for disease diagnosis and differential diagnosis. Method: From 2012 to 2018, patients diagnosed with PSS or primary biliary cholangitis (PBC) admitted consecutively to the department of Rheumatology at Peking Union Medical College Hospital were retrospectively included in this study. Glycan profiles of serum IgG from 40 PSS patients, 50 PBC patients, and 38 healthy controls were detected with lectin microarray containing 56 lectins. Lectins with significantly different signal intensity among groups were selected and validated by lectin blot assay. Results: Lectin microarray analysis revealed that binding levels of Amaranthus Caudatus Lectin (ACL, prefers glycan Galß3GalNAc, P = 0.011), Morniga M Lectin (MNA-M, prefers glycan mannose. P = 0.013), and Lens Culinaris Agglutinin (LCA, prefers glycan fucose) were significantly increased, while Salvia sclarea Agglutinin (SSA, prefers glycan sialylation, P = 0.001) was significantly decreased in PSS patients compared to PBC group. Compared to healthy controls, MNA-M (P = 0.001) and LCA (P = 0.028) were also significantly increased, while Phaseolus Vulgaris Erythroagglutinin and Phaseolus Vulgaris Leucoagglutinin (PHA-E and PHA-L, prefer glycan galactose, P = 0.004 and 0.006) were significantly decreased in PSS patients. The results of LCA and MNA-M were further confirmed using lectin blot assay. Conclusion: Changes in serum IgG glycosylation in PSS increased binding levels of LCA and MNA-M lectins using microarray techniques compared to PBC patients and healthy controls, which could provide potential diagnostic value. Increased core fucose and mannose alteration of IgG may play important roles in PSS disease.

Platelets lipidomics study of blood stasis rat model by using liquid chromatography-tandem mass spectrometry.

This study analyzed a lipidomic profile of platelets from blood stasis rats by liquid chromatography-tandem mass spectrometry. The blood stasis rat was established by low-dose continuous subcutaneous injection of adrenaline, and the evaluation indexes included hemorheology and platelet aggregation. Principal component analysis and partial least-squares discriminant analysis were used to analyze platelet lipidomics, and p-value < 0.05, fold change > 1.5, and variable importance plot > 2 were used to screen potential biomarkers. Then, the biomarkers were optimized by the receiver operating characteristic curve. Compared with the normal rat, the blood stasis model group's whole blood viscosity and platelet aggregation rate were also significantly increased at different shear rates (p < 0.05). Twenty-four potential lipid biomarkers showed significant changes in platelets between the two groups. Among them, six long-chain acylcarnitine components and three sphingosine components showed a consistent downward trend, suggesting that these two kinds of components may play an essential role in the process of platelet aggregation. Liquid chromatography-tandem mass spectrometry-based lipidomics studies provide much information to understand the pathology of platelets in blood stasis.

Predicting plant diversity in beach wetland downstream of Xiaolangdi reservoir with UAV and satellite multispectral images.

Accurate and timely acquisition of plant diversity information downstream of the reservoir is helpful to understand the impact mechanism of reservoir operation on wetland plant diversity and formulate reasonable water and sediment regulation strategies. In this study, we conducted field surveys in two communities (Phragmites australis and Tamarix chinensis) at a typical wetland in the lower reaches of Xiaolangdi Reservoir on the Yellow River, and employed UAV and Gaofen 1B multispectral images to estimate the wetland plant diversity. Results showed that most diversity indexes had a higher correlation with the mean of spectral vegetation indexes (DVI, RVI, NDVI, SAVI, and MSAVI). The diversity indexes (C_SP and C_SW) constructed by relative coverage had a better overall correlation with spectral indexes. Interestingly, opposite correlations were found between Tamarix chinensis and Phragmites australis plots. We further gave a deep insight into the interspecific associations in Phragmites australis and Tamarix chinensis plots with the variance ratio (VR) method. It was found that plant species in Tamarix chinensis plot showed positive association (VR > 1), with a VR value of 1.095. Plant species in Phragmites australis plot had a negative association (VR < 1), with a VR value of 0.983. In Phragmites australis plot, C_SP and C_SW showed a significant decreasing trend (r2 of 0.36 and 0.33 respectively, and P values less than 0.001) with the increase of Phragmites australis coverage. Moreover, the effect of spatial resolution was not significant on plant diversity estimation. Correlations between remote sensing indexes and diversity indexes were improved with the quadrat size changing from 2 m × 2 m to 4 m × 4 m. These findings demonstrate promising approaches for remote sensing of wetland plant diversity and indicate that the type of wetland plant community determines the relationship between diversity index and spectral index.

Hepatocyte steatosis inhibits hepatitis B virus secretion via induction of endoplasmic reticulum stress.

The effects of hepatocyte steatosis on hepatitis B virus (HBV) DNA replication and HBV-related antigen secretion are incompletely understood. The aims of this study are to explore the effects and mechanism of hepatocyte steatosis on HBV replication and secretion. Stearic acid (SA) and oleic acid (OA) were used to induce HepG2.2.15 cell steatosis in this study. The expressions of glucose-regulated protein 78 (GRP78), phosphorylation of protein kinase R-like endoplasmic reticulum (ER) kinase (p-PERK), and eukaryotic translation initiation factor 2α (p-eIF2α) were detected by Western blotting (WB). HBV DNA, HBsAg, and HBeAg in the supernatant were determined by real-time fluorescent polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay. Intracellular HBV DNA, HBsAg level, and HBV RNA were measured by real-time fluorescent PCR, WB, and real-time quantitative reverse transcriptase-PCR, respectively. The results showed that SA and OA significantly increased intracellular lipid droplets and triglyceride levels. SA and OA significantly induced GRP78, p-PERK, and p-eIF2α expressions from 24 to 72 h. 4-phenylbutyric acid (PBA) alleviated ER stress induced by SA. SA promoted intracellular HBsAg and HBV DNA accumulation; however, it inhibited the transcript of HBV 3.5 kb mRNA and S mRNA. The secretion of HBsAg and HBV DNA inhibited by SA or OA could be partially restored by pretreatment with PBA but not by inhibiting GRP78 expression with siRNA. Hepatocyte steatosis inhibits HBsAg and HBV DNA secretion via induction of ER stress in hepatocytes, but not via induction of GRP78.

Effects of different plasma target concentrations of remifentanil on the MACBAR of sevoflurane in children with laparoscopic surgery.

BACKGROUND: To investigate the effects of different plasma target concentrations of remifentanil on the minimum alveolar concentration (MAC) for blocking adrenergic response (BAR) of sevoflurane in children with laparoscopic herniorrhaphy. METHODS: Seventy-five children with 3-7 years old scheduled for laparoscopic herniorrhaphy were randomly divided into group R0, group R1, and group R2 according to different remifentanil plasma target concentration (0, 1, and 2 ngml-1), respectively. The MACBAR of sevoflurane was determined by the up-and-down and sequential method in each group. The concentrations of epinephrine and noradrenaline were also determined at corresponding time points. RESULTS: A total of 52 child patients were used among the anticipated 75 patients. In groups R0, R1, and R2, the MACBAR of sevoflurane was (3.29 ± 0.17) %, (2.12 ± 0.10) % and (1.29 ± 0.11) %, respectively, and a significant difference was found among the three groups (P<0.05). The changes of epinephrine and noradrenaline concentrations in each group before and after insufflation of carbon dioxide pneumoperitoneum showed no significant differences. CONCLUSION: Remifentanil by target-controlled infusion can effectively reduce the MACBAR of sevoflurane during laparoscopic surgery in children. At a similar effect of MACBAR, both the changes of epinephrine and noradrenaline concentrations are not affected by the infusion of different remifentanil target concentrations. TRIAL REGISTRATION: The trial was registered at http://www.chictr.org.cn ( ChiCTR1800019393 , 8, Nov, 2018).

Changes of Serum IgG Glycosylation Patterns in Primary Biliary Cholangitis Patients.

Objective: Primary biliary cholangitis (PBC) is an autoimmune cholestatic liver disease whose diagnosis is based significantly on autoantibody detection. This study aims to investigate the glycosylation profile of serum IgG in PBC patients using high-throughput lectin microarrays technology. Method: Lectin microarray containing 56 lectins was used to detect and analyze the expression of serum IgG glycosylation in 99 PBC patients, 70 disease controls (DCs), and 38 healthy controls (HCs). Significant differences in PBC from control groups as well as across PBC subgroups positive for various autoantibodies were explored and verified by lectin blot technique. Results: Lectin microarray detection revealed that compared to DC and HC groups, the specific glycan level of serum IgG sialic acid in PBC patients was increased. For each PBC subgroup, glycan levels of IgG mannose and galactose were decreased in AMA-M2 positive PBC patients compared to the AMA-M2 negative group. IgG N-Acetylgalactosamine (GalNAc) and fucose were decreased in anti-sp100 positive patients. IgG galactose was increased in anti-gp210 positive patients. IgG mannose was decreased in ACA-positive patients. Although the difference in overall sialic acid level was not observed using lectin blot, all results among the above PBC subgroups were consistent with the results of the technique. Conclusion: Lectin microarray is an effective and reliable technique for analyzing glycan structure. PBC patients positive for different autoantibody exhibits distinct glycan profile. Altered levels of glycosylation may be related to the occurrence and development of the disease, which could provide a direction for new biomarker identification.

Stem-loop-primer assisted isothermal amplification enabling high-specific and ultrasensitive nucleic acid detection.

It is highly desired to perform accurate and rapid nucleic acid detections for disease diagnosis at resource-limited setting, such as small clinics, remote areas and home. However, the challenges in sample handling, expensive equipment and complicated operation make canonical polymerase chain reaction (PCR) impossible to run the point-of-care testing (POCT). Herein we report a novel nucleic acid detection method, named stem-loop-primer assisted isothermal amplification (SPA), which specifically and sensitively amplifies target nucleic acid by using Bst DNA polymerase, a pair of canonical PCR primers and their stem-loop derivatives. The stem-loop-primers are easily designed by adding a stem-loop sequence to the canonical PCR primers at 5'-ends. In contrast to loop-mediated isothermal amplification (LAMP), which is a widespread isothermal amplification technology, our SPA is more specific and convenient to design and run. Further, we have demonstrated that SPA can specifically detect type 16, 18, 52 and 58 Human Papilloma viruses (HPV) in cervical samples, suggesting its specificity and robustness for nucleic acid detection. Moreover, pH indicator based colorimetric SPA was developed, which offered 100% accuracy for HPV16 detection in cervical samples, thereby demonstrating its great potential for POCT nucleic acid testing.

Correction to: Effects of different sufentanil target concentrations on the MACBAR of sevoflurane in patients with carbon dioxide pneumoperitoneum stimulus.

An amendment to this paper has been published and can be accessed via the original article.

Effects of different sufentanil target concentrations on the MACBAR of sevoflurane in patients with carbon dioxide pneumoperitoneum stimulus.

BACKGROUND: This study aims to observe the effects of different target controlled plasma sufentanil concentrations on the minimum alveolar concentration (MAC) of sevoflurane for blocking adrenergic response (BAR) in patients undergoing laparoscopic cholecystectomy with carbon dioxide pneumoperitoneum stimulation. METHODS: Eighty-five patients undergoing laparoscopic cholecystectomy, aged 30-65 years, with American Society of Anesthesiologists physical status I-II, were enrolled in this study. All the patients were randomly divided into 5 groups (S0, S1, S2, S3, S4) with different sufentanil plasma target concentration (0.0, 0.1, 0.3, 0.5, 0.7 ng ml- 1). Anesthesia was induced by inhalation of 8% sevoflurane in 100% oxygen, and 0.6 mg kg- 1 of rocuronium was intravenously injected to facilitate the insertion of a laryngeal mask airway. The end-tidal sevoflurane concentration and sufentanil plasma target concentration were adjusted according to respective preset value in each group. The hemodynamic response to pneumoperitoneum stimulus was observed after the end-tidal sevoflurane concentration had been maintained stable at least for 15 min. The MACBAR of sevoflurane was measured by a sequential method. Meanwhile, epinephrine (E) and norepinephrine (NE) concentrations in the blood were also determined before and after pneumoperitoneum stimulus in each group. RESULTS: When the method of independent paired reversals was used, the MACBAR of sevoflurane in groups S0, S1, S2, S3, S4 was 5.333% (confidence interval [CI] 95%: 5.197-5.469%), 4.533% (95% CI: 4.451-4.616%), 2.861% (95% CI: 2.752-2.981%), 2.233% (95% CI: 2.142-2.324%) and 2.139% (95% CI: 2.057-2.219%), respectively. Meanwhile, when the isotonic regression analysis was used, the MACBAR of sevoflurane in groups S0, S1, S2, S3, S4 was 5.329% (95% CI: 5.321-5.343%), 4.557% (95% CI: 4.552-4.568%), 2.900% (95% CI: 2.894-2.911%), 2.216% (95% CI: 2.173-2.223%) and 2.171% (95% CI: 2.165-2.183%), respectively. The MACBAR was not significantly different between groups S3 and S4 when using 0.5 and 0.7 ng ml- 1 of sufentanil plasma target concentrations. No significant difference was found in the change of E or NE concentration between before and after pneumoperitoneum stimulation in each group. CONCLUSIONS: The MACBAR of sevoflurane can be decreased with increasing sufentanil plasma target concentrations. A ceiling effect of the decrease occurred at a sufentanil plasma target concentration of 0.5 ng ml- 1. When the sympathetic adrenergic response was inhibited in half of the patients to pneumoperitoneum stimulation in each group, the changes of E and NE concentrations showed no significant differences. TRIAL REGISTRATION: The study was registered at http://www.chictr.org.cn ( ChiCTR1800015819 , 23, April, 2018).

Mechanism of heparin interference in detection of LIAISON® Rubella IgM.

AIMS: To investigate the effects of heparin in detection of LIAISON® Rubella IgM (Rub-M) and the mechanism of interference. METHODS: Different concentrations of lithium heparin and sodium heparin were added to ten serum samples. The relative light units (RLU) value of Rub-M was measured using the LIAISON XL detection system. Different levels of IgM serum were incubated with magnetic particle in Rub-M detection kit at 4 °C for 4 h, blocking anti-human IgM-specific antibodies coated on the surface of magnetic particle. Separately, the rubella virus antigen in Rub-M detection kit was replaced by phosphate-buffered saline (PBS). The RLU values of LIAISON® Rub-M of original serum and serum containing various concentrations of heparin were measured after the above two different treatments. RESULTS: The RLU value of LIAISON® Rub-M increased with the increase of heparin content lower than 40 IU/mL, and reached a peak value at 40-50 IU/mL. The RLU value of LIAISON® Rub-M then decreased with the decrease of heparin concentration. When rubella virus antigen was replaced by PBS, the RLU value of LIAISON® Rub-M of serum samples containing 40 IU/mL heparin decreased significantly. The blocking concentration of IgM increased gradually, and the RLU value of LIAISON® Rub-M of seven serum samples containing 40 IU/mL heparin also decreased gradually. CONCLUSION: Plasma with heparin cannot be used to the detection of LIAISON® Rub-M. Heparin may participate in the reaction by binding with rubella virus antigen and anti-human IgM-specific antibodies coated on the surface of magnetic particle, thus affecting the detection results.

Diagnostic value of the γ-glutamyltransferase and alanine transaminase ratio, alpha-fetoprotein, and protein induced by vitamin K absence or antagonist II in hepatitis B virus-related hepatocellular carcinoma.

Hepatocellular carcinoma is a common type of malignancy with a poor prognosis. Identification and utilisation of markers for monitoring and diagnosis are urgently needed. Alpha-fetoprotein (AFP) and Protein Induced by Vitamin K Absence or Antagonist-II (PIVKA-II) have been proved to be efficient biomarkers for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The combination of the two markers could improve the detection rate. However, these indicators cannot meet the need of clinical diagnosis.It is necessary to discover novel serological markers and more cost-effective, appropriate combination of these markers for the diagnosis and surveillance of HBV-related HCC. Accordingly, in this study, we aimed to evaluate the diagnostic value of γ-glutamyltransferase (γ-GT) to alanine amino transferase (ALT) ratio alone or in combination with AFP and PIVKA-II for HBV-related HCC. 234 patients with HBV-related HCC and 396 patients with chronic hepatitis B (CHB) were enrolled in this study and approved by the institutional review board. Our results showed levels of AFP and PIVKA-II, and γ-GT/ALT ratio in cases with early-stage HCC, HCC, HCC plus HBV DNA positivity, and HCC plus HBV DNA negativity were higher than those in the corresponding CHB control group. Additionally, the levels of serum AFP and PIVKA-II, and the γ-GT/ALT ratio were positively correlated with tumour sizes in patients with HBV-related HCC. The areas under the ROC curves (AUROCs) of the γ-GT/ALT ratio in patients with early-stage HCC, HCC, HCC plus HBV DNA positivity, and HCC plus HBV DNA negativity were 0.795, 0.846,0.855, and 0.837, respectively; AUROCs of combination of the γ-GT/ALT ratio and PIVKA-II were 0.858, 0.928, 0.948, and 0.902, respectively; AUROCs of combination of the γ-GT/ALT ratio and AFP were 0.822, 0.886, 0.896, and 0.873, respectively;AUROCs of combination of the γ-GT/ALT ratio and PIVKA-II with AFP were 0.857, 0.928, 0.946, and 0.907, respectively, and AUROCs of combination of PIVKA-II and AFP were 0.804, 0.904, 0.942, and 0.863, respectively. In conclusion, the γ-GT/ALT ratio was a useful biomarker for the diagnosis of HBV-related HCC and that the combination of AFP and PIVKA-II with the γ-GT/ALT ratio could improve the diagnostic value of these biomarkers for HBV-related HCC. Moreover, the ratio of γ-GT/ALT may be a useful index in monitoring patients for progression of HBV-related HCC.

[Cyanosis for more than 4 years in a girl aged 4 years and 3 months].

A girl, aged 4 years and 3 months, presented with cyanosis of the lips shortly after birth. She then experienced shortness of breath after activity 1 year ago and acrocyanosis 3 months ago, with obvious acropachy and toe deformity. Laboratory examinations revealed an increase in hemoglobin (178 g/L) and a reduction in arterial partial pressure of oxygen (37.7 mm Hg). Plain and contrast-enhanced CT scans of the lungs showed a large area of dense shadow and multiple nodules with clear boundaries in the right lower lung, as well as thickening of the arteries and dilatation of the veins in the right lower lung. Magnetic resonance angiography of the pulmonary artery showed large arteriovenous malformation in the lung. The child was diagnosed with congenital pulmonary arteriovenous fistula and was given interventional embolization of the pulmonary arterial fistula. The child was followed up at 3 months after surgery. The symptoms of shortness of breath and cyanosis disappeared, and activity tolerance, heart rate, hemoglobin, red blood cell count, and transcutaneous oxygen saturation all returned to normal.

A Method To Prevent SARS-CoV-2 IgM False Positives in Gold Immunochromatography and Enzyme-Linked Immunosorbent Assays.

We set out to investigate the interference factors that led to false-positive novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM detection results using gold immunochromatography assay (GICA) and enzyme-linked immunosorbent assay (ELISA) and the corresponding solutions. GICA and ELISA were used to detect SARS-CoV-2 IgM in 86 serum samples, including 5 influenza A virus (Flu A) IgM-positive sera, 5 influenza B virus (Flu B) IgM-positive sera, 5 Mycoplasma pneumoniae IgM-positive sera, 5 Legionella pneumophila IgM-positive sera, 6 sera of HIV infection patients, 36 rheumatoid factor IgM (RF-IgM)-positive sera, 5 sera from hypertensive patients, 5 sera from diabetes mellitus patients, and 14 sera from novel coronavirus infection disease 19 (COVID-19) patients. The interference factors causing false-positive reactivity with the two methods were analyzed, and the urea dissociation test was employed to dissociate the SARS-CoV-2 IgM-positive serum using the best dissociation concentration. The two methods detected positive SARS-CoV-2 IgM in 22 mid-to-high-level-RF-IgM-positive sera and 14 sera from COVID-19 patients; the other 50 sera were negative. At a urea dissociation concentration of 6 mol/liter, SARS-CoV-2 IgM results were positive in 1 mid-to-high-level-RF-IgM-positive serum and in 14 COVID-19 patient sera detected using GICA. At a urea dissociation concentration of 4 mol/liter and with affinity index (AI) levels lower than 0.371 set to negative, SARS-CoV-2 IgM results were positive in 3 mid-to-high-level-RF-IgM-positive sera and in 14 COVID-19 patient sera detected using ELISA. The presence of RF-IgM at mid-to-high levels could lead to false-positive reactivity of SARS-CoV-2 IgM detected using GICA and ELISA, and urea dissociation tests would be helpful in reducing SARS-CoV-2 IgM false-positive results.

[Clinical features of neuroendocrine cell hyperplasia of infancy].

OBJECTIVE: To study the clinical features of neuroendocrine cell hyperplasia of infancy (NEHI) in order to provide a basis for the management of diagnosis, treatment and prognosis of children with NEHI. METHODS: A retrospective analysis was performed for the clinical data of seven children with NEHI who were diagnosed and treated from January 2014 to March 2016. RESULTS: Among the seven children with NEHI, there were five boys and two girls. Two children experienced tachypnea since the neonatal period, and five children developed respiratory tract symptoms within 1-6 months after birth. Of the 7 children, 6 had pulmonary crackles, 4 had hypoxemia, and 3 had gastroesophageal reflux. Lung high-resolution CT (HRCT) showed ground-glass opacities in the central region of the lungs in all children, which involved at least two lung lobes. Of the 7 children, 2 had the involvement of more than 4 lobes and 6 had air trapping. All 7 children had an improvement in clinical symptoms after two years of age. One child achieved clinical and CT remission. Four children achieved clinical remission, but still with CT changes. CONCLUSIONS: NEHI often occurs in infancy, with the major clinical manifestations of persistent tachypnea, pulmonary crackles, and hypoxemia. The children with NEHI often present ground-glass opacities in the central region of the lungs and air trapping on HRCT. There is no specific treatment for this disease and most cases have a good prognosis.

A simple formula to correct for the effects of storage time and temperature on the insulin concentration.

OBJECTIVE: To investigate the influence of storage time and temperature on plasma insulin levels and to establish a correction formula. METHODS: Venous blood samples were taken from 20 volunteers and processed as follows: whole blood samples, centrifuged samples, and separated plasma samples were stored at 4°C or 25°C. Insulin levels were determined by direct chemiluminescence at 0, 0.5, 1, 2, 4, and 8 hours. According to the correlation between the insulin concentration ratio and storage time, correction formulas for the insulin concentration were established. To verify the test, the venous blood samples of another 33 volunteers were processed in the same way. The insulin levels of the samples were corrected after 3, 6, 12, and 24 hours and compared with the value at 0 hours to verify the feasibility of the corrected formula. RESULTS: With the prolongation of storage time, the insulin levels of the whole blood samples at 4°C or 25°C and of the centrifuged samples at 25°C decreased gradually (P < .001), and the insulin level correction formulas were Ccorrection  = Cdetermination /0.991e-0.069 x , Ccorrection  = Cdetermination /1.048e-0.126 x , and Ccorrection  = Cdetermination /[-0.068ln(x) + 0.9242]. There was no significant difference between the corrected insulin results and the original results at any time within 12 hours (P > .05). CONCLUSIONS: The insulin levels of the whole blood samples at 4°C or 25°C and of the plasma samples at 25°C gradually decreased with storage time. The effect of storage time on the insulin level can be reduced with the correction formulas.