Microbiome-based classification models for fresh produce safety and quality evaluation

Small sample sizes and loss of sequencing reads during the microbiome data preprocessing can limit the statistical power of differentiating fresh produce phenotypes and prevent the detection of important bacterial species associated with produce contamination or quality reduction. Here, we explored a machine learning-based k-mer hash analysis strategy to identify DNA signatures predictive of produce safety (PS) and produce quality (PQ) and compared it against the amplicon sequence variant (ASV) strategy that uses a typical denoising step and ASV-based taxonomy strategy. Random forest-based classifiers for PS and PQ using 7-mer hash data sets had significantly higher classification accuracy than those using the ASV data sets. We also demonstrated that the proposed combination of integrating multiple data sets and leveraging a 7-mer hash strategy leads to better classification performance for PS and PQ compared to the ASV method but presents lower PS classification accuracy compared to the feature-selected ASV-based taxonomy strategy. Due to the current limitation of generating taxonomy using the 7-mer hash strategy, the ASV-based taxonomy strategy with remarkably less computing time and memory usage is more efficient for PS and PQ classification and applicable for important taxa identification. Results generated from this study lay the foundation for future studies that wish and need to incorporate and/or compare different microbiome sequencing data sets for the application of machine learning in the area of microbial safety and quality of food.

IMPORTANCE

Identification of generalizable indicators for produce safety (PS) and produce quality (PQ) improves the detection of produce contamination and quality decline. However, effective sequencing read loss during microbiome data preprocessing and the limited sample size of individual studies restrain statistical power to identify important features contributing to differentiating PS and PQ phenotypes. We applied machine learning-based models using individual and integrated k-mer hash and amplicon sequence variant (ASV) data sets for PS and PQ classification and evaluated their classification performance and found that random forest (RF)-based models using integrated 7-mer hash data sets achieved significantly higher PS and PQ classification accuracy. Due to the limitation of taxonomic analysis for the 7-mer hash, we also developed RF-based models using feature-selected ASV-based taxonomic data sets, which performed better PS classification than those using the integrated 7-mer hash data set. The RF feature selection method identified 480 PS indicators and 263 PQ indicators with a positive contribution to the PS and PQ classification.

Oxidized konjac glucomannan: A safe dietary fiber influencing mouse gut microbiota

In this 13-week study, the potential effects of oxidized konjac glucomannan (OKGM) on ICR mice's metabolic health and gut microbiota were investigated and contrasted with enzyme-hydrolyzed KGM (EKGM) at a same molecular weight. Mice were fed diets containing 0 %, 2.5 %, 5.0 %, and 7.5 % of OKGM for 13 weeks. Results indicated that OKGM induced no adverse effects, with overall health, body weight gain, food consumption, and clinical pathology parameters being comparable to the control group. The no-observed-adverse-effect-level for OKGM was determined at 7.5 % in the diet, corresponding to 10.21 and 12.01 g/kg/day for male and female mice, respectively. OKGM intake positively regulated gut microbiota, characterized by a reduction in the relative abundance of Firmicutes, an increase in Bacteroidetes, and an enhanced presence of Lactobacillus, particularly Lactobacillus reuteri. In comparison, EKGM differently modulated the microbiota, notably increasing Muribaculaceae. These findings suggest that OKGM has the potential to be a functional food additive.

Age effect on the shared etiology of glycemic traits and serum lipids: evidence from a Chinese twin study

PURPOSE

Diabetes and dyslipidemia are among the most common chronic diseases with increasing global disease burdens, and they frequently occur together. The study aimed to investigate differences in the heritability of glycemic traits and serum lipid indicators and differences in overlapping genetic and environmental influences between them across age groups.

METHODS

This study included 1189 twin pairs from the Chinese National Twin Registry and divided them into three groups: aged ≤ 40, 41-50, and > 50 years old. Univariate and bivariate structural equation models (SEMs) were conducted on glycemic indicators and serum lipid indicators, including blood glucose (GLU), glycated hemoglobin A1c (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), in the total sample and three age groups.

RESULTS

All phenotypes showed moderate to high heritability (0.37-0.64). The heritability of HbA1c demonstrated a downward trend with age (HbA1c: 0.50-0.79), while others remained relatively stable (GLU: 0.55-0.62, TC: 0.58-0.66, TG: 0.50-0.63, LDL-C: 0.24-0.58, HDL-C: 0.31-0.57). The bivariate SEMs demonstrated that GLU and HbA1c were correlated with each serum lipid indicator (0.10-0.17), except HDL-C. Except for HbA1c and LDL-C, as well as HbA1c and HDL-C, differences in genetic correlations underlying glycemic traits and serum lipids between age groups were observed, with the youngest group showing a significantly higher genetic correlation than the oldest group.

CONCLUSION

Across the whole adulthood, genetic influences were consistently important for GLU, TC, TG, LDL-C and HDL-C, and age may affect the shared genetic influences between glycemic traits and serum lipids. Further studies are needed to elucidate the role of age in the interactions of genes related to glycemic traits and serum lipids.

Fitness and transcriptomic analysis of pathogenic Vibrio parahaemolyticus in seawater at different shellfish harvesting temperatures

IMPORTANCE

Given the involvement of Vibrio parahaemolyticus (Vp) in a wide range of seafood outbreaks, a systematical characterization of Vp fitness and transcriptomic changes at temperatures of critical importance for seafood production and storage is needed. In this study, one of each virulent Vp strain (tdh+ and trh+) was tested. While no difference in survival behavior of the two virulent strains was observed at 10°C, the tdh+ strain had a faster growth rate than the trh+ strain at 30°C. Transcriptomic analysis showed that a significantly higher number of genes were upregulated at 30°C than at 10°C. The majority of differentially expressed genes of Vp at 30°C were annotated to functional categories supporting cellular growth. At 10°C, the downregulation of the biofilm formation and histidine metabolism indicates that the current practice of storing seafood at low temperatures not only protects seafood quality but also ensures seafood safety.

CRISPR genetic toolkits of classical food microorganisms: Current state and future prospects

Production of food-related products using microorganisms in an environmentally friendly manner is a crucial solution to global food safety and environmental pollution issues. Traditional microbial modification methods rely on artificial selection or natural mutations, which require time for repeated screening and reproduction, leading to unstable results. Therefore, it is imperative to develop rapid, efficient, and precise microbial modification technologies. This review summarizes recent advances in the construction of gene editing and metabolic regulation toolkits based on the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (CRISPR-Cas) systems and their applications in reconstructing food microorganism metabolic networks. The development and application of gene editing toolkits from single-site gene editing to multi-site and genome-scale gene editing was also introduced. Moreover, it presented a detailed introduction to CRISPR interference, CRISPR activation, and logic circuit toolkits for metabolic network regulation. Moreover, the current challenges and future prospects for developing CRISPR genetic toolkits were also discussed.

Genomic epidemiological investigation of an outbreak of Serratia marcescens neurosurgical site infections associated with contaminated haircutting toolkits in a hospital barber shop

BACKGROUND

Nine surgical site infections caused by Serratia marcescens were diagnosed in neurosurgical patients in a 3500-bed hospital between 2nd February and 6th April 2022.

OBJECTIVE

To trace the source of infections caused by S. marcescens to expedite termination of the outbreak and prevent future epidemics.

METHODS

A review of all surgical procedures and cultures yielding S. marcescens since February 2022 was conducted. Samples were collected from patients and environmental sources. S. marcescens isolates were characterized by antibiotic susceptibility testing. Whole-genome sequencing (WGS) was used to investigate genetic relationships. Resistance genes, virulence genes and plasmid replicons were identified.

RESULTS

S. marcescens was isolated from patients' puncture fluid, cerebrospinal fluid and other secretions, and was also cultured from the barbers' haircutting tools, including leather knives, slicker scrapers and razors. In total, 15 isolates were obtained from patients and eight isolates were obtained from haircutting tools. All isolates exhibited identical antibiotic resistance patterns. WGS revealed close clustering among the 23 isolates which differed significantly from previous strains. Three resistance genes and nine virulence-associated genes were detected in all isolates, and 19 of 23 isolates harboured an MOBP-type plasmid. The results confirmed an outbreak of S. marcescens, which was traced to contaminated haircutting tools in the hospital barber shop. The outbreak ended after extensive reinforcement of infection control procedures and re-education of the barbers.

CONCLUSIONS

These results highlight the risk of postoperative infections related to pre-operative skin preparation, and demonstrate the value of next-generation sequencing tools to expedite outbreak investigations.

A systematic review and meta-analysis of loratadine combined with montelukast for the treatment of allergic rhinitis

Background: Loratadine and montelukast are clinical first-line drugs in the treatment of allergic rhinitis (AR). However, there is no clear evidence of the efficacy of loratadine combined with montelukast in the treatment of AR. This study aimed to evaluate the efficacy and safety of the loratadine-montelukast combination on AR. Methods: In this meta-analysis, searches were conducted on PubMed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and China National Knowledge Infrastructure (CNKI). The search terms included loratadine, montelukast, allergic rhinitis, and clinical trials. Meta-analyses were conducted using Rev Man 5.3 and Stata 15 statistical software. Results: A total of 23 studies with 4,902 participants were enrolled. For the primary outcome, pooled results showed that loratadine-montelukast can significantly reduce total nasal symptom scores (TNSS), when compared with loratadine (SMD, -1.00; 95% CI, -1.35 to -0.65, p < 0.00001), montelukast (SMD, -0.46; 95% CI, -0.68 to -0.25, p < 0.0001), or placebo (SMD, -0.93; 95% CI, -1.37 to -0.49, p < 0.00001). For secondary outcomes, pooled results showed that compared with loratadine, loratadine-montelukast can significantly improve nasal congestion, nasal itching, nasal sneezing, nasal rhinorrhea, and rhinoconjunctivitis quality of life questionnaires (RQLQ). Compared with montelukast, loratadine-montelukast can significantly improve nasal itching, and nasal sneezing. Compared with placebo, loratadine-montelukast can significantly improve nasal congestion, and RQLQ. Conclusion: Loratadine-montelukast combination is superior to loratadine monotherapy, montelukast monotherapy, or placebo in improving AR symptoms. Therefore, loratadine-montelukast combination can be an option for patients with moderate-severe AR or poorly response to monotherapy. Systematic review registration number: clinicaltrials.gov, identifier CRD42023397519.

The effects of GLP-1 receptor agonists on visceral fat and liver ectopic fat in an adult population with or without diabetes and nonalcoholic fatty liver disease: A systematic review and meta-analysis

AIM

To uncover the effect of GLP-1 receptor agonists (GLP-1 RAs) on the visceral- and hepatic fat content of adults.

METHODS

PubMed, EMBASE, Cochrane Library, and Web of Science were searched from inception until November 2022. Randomized controlled trials (RCTs) of GLP-1Ras was extracted, including reports of effects on visceral adipose tissue and hepatic fat content in individuals with type 2 diabetes, non-type 2 diabetes, NAFLD (non-alcoholic fatty liver disease), and non-NAFLD. Meta-analyses used random-effects models.

RESULTS

1736 individuals in the 30 qualified RCTs were included, comprising 1363 people with type 2 diabetes and 318 with NFLD. GLP-1 RAs reduced visceral adipose tissue (standard mean difference [SMD] = -0.59, 95% CI [-0.83, -0.36], P<0.00001) and hepatic fat content (weighted mean difference [WMD] = -3.09, 95% CI [-4.16, -2.02], P<0.00001) compared to other control treatment. Subgroup analysis showed that GLP-1Ras dramatically decreased visceral fat in patients with type 2 diabetes (SMD = -0.49, 95% CI [-0.69, -0.29] P<0.00001), NAFLD (SMD = -0.99, 95% CI [-1.64, -0.34] P = 0.003), non-type 2 diabetes (SMD = -1.38, 95% CI [-2.44, -0.32] P = 0.01), and non-NAFLD (SMD = -0.53, 95% CI [-0.78, -0.28] P<0.0001). GLP-1Ras reduced the liver fat level of type 2 diabetes (WMD = -3.15, 95% CI [-4.14, -2.15] P<0.00001), NAFLD (WMD = -3.83, 95% CI [-6.30, -1.37] P = 0.002), and type 2 diabetes with NAFLD (WMD = -4.27, 95% CI [-6.80, -1.74] P = 0.0009), while showed no impact on the hepatic fat content in non-Type 2 diabetes (WMD = -12.48, 95% CI [-45.19, 20.24] P = 0.45).

CONCLUSIONS

LP-1 RAs significantly reduce visceral- and liver fat content in adults.

Prevalence and risk factors of chronic rhinosinusitis among Chinese: A systematic review and meta-analysis

Background

Chronic rhinosinusitis (CRS) can be seen in people of all ages. CRS heavily affects the quality of a patient's daily life and also causes tremendous economic burdens on patients' families and society. The prevalence of CRS in different countries varies and no systematic review of the prevalence of CRS among Chinese has been published previously. The objective of this systematic review and meta-analysis is to determine the prevalence of CRS among Chinese and to explore the main risk factors of CRS among Chinese.

Methods

Using relevant keywords, data resources including PubMed, Scopus, Web of Science, Google Scholar, Embase, Cochrane Library, Chinese National Knowledge of Infrastructure (CNKI), WANGFANG, VIP, and China Biomedical Literature database (CMB) were searched to obtain literature reporting the prevalence of and risk factors of CRS among Chinese which were clearly diagnosed with CRS from inception to 30 June 2022. The random/fixed effect model was used for meta-analysis, and the I² index was employed to assess heterogeneity among studies. All analyses were performed by using the STATA version 16.0 software. The study was registered with PROSPERO, register number. CRD42022341877.

Result

A total of 12 relevant kinds of literature were qualified for the present systematic review, including 4,033 patients. The results showed that the overall prevalence of CRS among Chinese was 10% (95%CI: 0.06-0.13, I² = 99.6%, P < 0.001). The prevalence of CRS among Chinese who lived in urban cities was 18% (95%CI: -0.07 to 0.43, I² = 99.9%, P < 0.001), which was obviously lower than the prevalence of CRS among Chinese who lived in rural areas (27%, 95%CI: -0.14 to 0.68, I² = 99.8%, P < 0.001). The prevalence of CRS among Chinese before 2010 was 23% (95%CI: -0.05 to 0.50, I² = 99.8%, P < 0.001), which was remarkably higher than the prevalence of CRS among Chinese after 2010 (7%, 95%CI: 0.05-0.09, I² = 99.0%, P < 0.001). The prevalence of CRS among Chinese who were divorced was 17% (95%CI: 0.12-0.22, I² = 0.0%, P = 0.436), while the prevalence of CRS among Chinese who were married, widowed, and unmarried was 9% (95%CI: 0.06-0.11, I² = 88.1%, P = 0.004), 9% (95%CI: 0.06-0.11, I² = 0.0%, P = 0.863), and 9% (95%CI: 0.08-0.10, I² = 0.0%, P = 0.658), respectively. The prevalence of CRS among Han and minority Chinese was 8% (95%CI: 0.07-0.10, I² = 69.6%, P = 0.070) and 12% (95%CI: 0.10-0.15, I² = 38.6%, P = 0.202), respectively. The prevalence of CRS among Chinese who was never exposed to moldy or damp environments was 8% (95%CI: 0.08-0.09, I² = 0.0%, P = 0.351), the prevalence of CRS among Chinese who was occasionally exposed to moldy or damp environments was 16% (95%CI: 0.10-0.22, I² = 78.9%, P = 0.030), and the prevalence of CRS among Chinese who was frequently or every day exposed to moldy or damp environments was up to 20% (95%CI: 0.15-0.24, I² = 0.0%, P = 0.558).

Conclusion

This meta-analysis shows that the prevalence of CRS among Chinese is at a high level. People who have some risk factors, such as occasional or frequent or everyday exposure to moldy or damp environments, have a higher prevalence of CRS. We should attach more importance to the risk factors of CRS in clinical practice and disseminate scientific information and carry out education to lower the prevalence of CRS in China.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=341877, identifier: CRD42022341877.

[Prenatal genetic diagnosis of the fetuses with isolated corpus callosum abnormality]

Objective: To explore the application value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in prenatal diagnosis of isolated corpus callosum abnormality (CCA) fetus. Methods: Fetuses diagnosed with isolated CCA by ultrasound and MRI and receiving invasive prenatal diagnosis in Guangzhou Women and Children's Medical Center and Qingyuan People's Hospital from January 2010 to April 2021 were selected. Karyotype analysis and/or CMA [or copy number variation sequencing (CNV-seq)] were performed on all fetal samples, and WES was performed on fetal samples and their parents whose karyotype analysis and/or CMA (or CNV-seq) results were not abnormal. Results: Among 65 fetuses with isolated CCA, 38 cases underwent karyotype analysis, and 3 cases were detected with abnormal karyotypes, with a detection rate of 8% (3/38). A total of 49 fetuses with isolated CCA underwent CMA (or CNV-seq) detection, and 6 cases of pathogenic CNV were detected, the detection rate was 12% (6/49). Among them, the karyotype analysis results were abnormal, and the detection rate of further CMA detection was 1/1. The karyotype results were normal, and the detection rate of further CMA (or CNV-seq) detection was 14% (3/21). The detection rate of CMA as the first-line detection technique was 7% (2/27). A total of 25 fetuses with isolated CCA with negative results of karyotyping and/or CMA were tested by WES, and 9 cases (36%, 9/25) were detected with pathogenic genes. The gradient genetic diagnosis of chromosomal karyotyping, CMA and WES resulted in a definite genetic diagnosis of 26% (17/65) of isolated CCA fetuses. Conclusions: Prenatal genetic diagnosis of isolated CCA fetuses is of great clinical significance. The detection rate of CMA is higher than that of traditional karyotyping. CMA detection could be used as a first-line detection technique for fetuses with isolated CCA. WES could increase the pathogenicity detection rate of fetuses with isolated CCA when karyotype analysis and/or CMA test results are negative.

The Microbial Quality of Commercial Chopped Romaine Lettuce Before and After the “Use By” Date

In the United States, due to the limited information about the microbial quality and safety of fresh produce after the labeled open dates, unnecessary discarding of fresh produce in good conditions and food loss have been caused. The aim of this study was to address this knowledge gap and evaluate the microbial quality of commercial chopped Romaine lettuce (RL) on the “Use By” dates (UBD) and 5 days after the “Use By” dates (UBD5). The microbial quality was evaluated using culture-dependent and culture-independent methods. Three brands of RL samples, from early and late harvest seasons, were purchased from local grocery stores and stored at 4°C until 5 days after their UBD. On the UBD and UBD5, bagged lettuce was opened, homogenized, diluted, and plated onto plate count agar and anaerobic agar to obtain total aerobic plate counts (APC) and total anaerobic plate counts (AnPC). For the culture-independent method, DNA was extracted from each sample homogenate and used for 16S rRNA gene sequencing. The culture-dependent results showed that there was no significant change in APC or AnPC between UBD and UBD5 samples. The APC and AnPC ranged from 5.71 ± 0.74 to 7.89 ± 0.10 Log CFU/g and 1.75 ± 0.08 to 7.32 ± 0.61 Log CFU/g, respectively. No significant difference in alpha diversity, based on observed features and Shannon index values, was detected between UBD and UBD5 samples using 16S rRNA sequencing. Similarly, no difference was observed in beta diversity based on the Jaccard distance matrixes and the weighted Unifrac distance matrixes. Taxonomic analysis revealed 128 genera in all RL samples. The top five genera were Pseudomonas (with relative abundance ranging from 16.47 to 92.72%), Serratia (0–52.35%), Weissella (0–42.42%), Pantoea (0.17–21.33%), and Lactococcus (0–24.30%). The differential abundance analysis based on the ANCOM test showed that no bacteria were detected to have significantly differential abundance in RL between UBD and UBD5. In summary, both the culture-dependent and culture-independent results showed that there was no significant difference in the microbial quality of RL before and shortly after the UBD.

[Molecular studies on parental origin and cell stage of nondisjunction in sex chromosome aneuploidies]

To study the parental origin and cell stage of nondisjunction in sex chromosome aneuploidies. Retrospectiving and analyzing the results of 385 cases of SCA confirmed by QF-PCR and karyotype analysis in the prenatal diagnosis center of Guangzhou Women and Children Medical Center from January 2015 to December 2020. The types of samples and prenatal diagnosis indications were analyzed. The parental origin and cell stage of nondisjunction in sex chromosome aneuploidies analyzed by comparing the short tandem repeat (STR) peak patterns of samples from fetuses and maternal peripheral blood. The results show that (1) There were 324 cases of nonmosaic SCA, 113 cases (113/324, 34.9%) were 45, XO, 118 cases (118/324, 36.4%) were 47, XXY, 48 cases (48/324, 14.8%) were 47, XXX and 45 cases (45/324, 13.9%) were 47, XYY. 68 (45/324, 60.2%) cases of 45, X were detected in villus samples. The other SCA cases were mainly detected in amniotic fluid samples. There were 61 mosaic SCA samples, 58(58/61, 95.1%) of mosaic SCA samples were mosaic 45, X. (2) The top two indications of 45, X cases are increased nuchal translucency(53/113, 46.9%) and fetal cystic hygroma (41/113, 36.3%), while the most common indication of other types of SCA was high risk of NIPT(170/272, 62.5%). (3) Among 45, X cases, there were 88 cases (88/113, 77.9%) inherit their single X chromosome from their mother and 25 cases (25/119, 22.1%) from their father. In 47, XXY samples, 47 cases (47/118, 39.8%) of chromosome nondisjunction occurred in meiosis stage Ⅰ of oocytes, 51 cases (51/118, 43.2%) occurred in meiosis stage Ⅰ of spermatocytes, and 20 cases (20/118, 16.9%) occurred in meiosis stage Ⅱ of oocytes. Among 47, XXX samples, 29 cases (29/48, 60.4%) of X chromosome nondisjunction occurred in meiosis stage Ⅰof oocytes, 15 cases (15/48, 31.3%) occurred in meiosis stage Ⅱ of oocytes, and 4 cases (4/48, 8.3%) occurred in meiosis stage Ⅱ of spermatocytes. In summary, the cases of 45, X were mainly diagnosed by villous samples for abnormal ultrasound findings. The other cases of SCA were mainly diagnosed by amniocentesis samples for abnormal NIPT results. Different types of SCA, the origin and occurrence period of sex chromosome nondisjunction were different.

Effectiveness of Low-temperature plasma tonsillectomy for chronic tonsillitis. A protocol of systematic review and meta-analysis

AIM

Recurrent episodes of chronic tonsillitis (CT) can affect a patient's quality of life, physical and mental health. Clinicians often perform surgeries to remove them. Traditional surgical methods are varied, despite their advantages. However, this remains controversial. This study aimed to examine both the safety and efficacy of low-temperature plasma tonsillectomy (LTPT) in treatment of chronic tonsillitis, which may provide a substitute for clinicians and compensate for the short supply of therapeutic procedures.

METHODS AND ANALYSIS

This protocol is guided by the Preferred Reporting Items for Systematic.

REVIEW AND META-ANALYSIS

Protocols (PRISMA-P) and by the Cochrane Collaboration Handbook. We will formulate strict inclusion and exclusion criteria in English databases (PubMed, EMBASE, and Web of Science) and search literature in different clinical registration platforms (Cochrane Library). The including articles were evaluated by the Cochrane RCT evaluation criteria. The primary main endpoints will include the duration of operation, blood loss during surgery, time of formation and exfoliation of the pseudomembrane, average pain and duration post-operation, and time for normal diet. The Secondary endpoints will include complications of postoperative bleeding and infection. Stata 15.0 will be used for data analysis. Subgroup analysis, sensitivity analysis, and meta-regression were used to detect the sources of heterogeneity. Begg's Test will quantitatively detect publication bias quantitatively.

ETHICS AND DISSEMINATION

The results of this meta-analysis and meta-regression will be disseminated through publication in a peer-reviewed journal. The data used in this meta-analysis will not contain individual patient data; therefore, ethical approval is not required.

KEY WORDS

Chronic tonsillitis, Low-temperature plasma tonsillectomy, Meta-analysis, Protocol, Systematic review.

Room temperature two terminal tunnel magnetoresistance in a lateral graphene transistor

We investigate the behavior of both pure spin and spin-polarized currents measured with four-probe non-local and two probe local configurations up to room temperature and under an external gate voltage in a lateral graphene transistor, produced using a standard large-scale microfabrication process. The high spin diffusion length of pristine graphene in the channel, measured both directly and by the Hanle effect, and the tuning of the relationship between the electrode resistance areas present in the device architecture allowed us to observe local tunnel magnetoresistance at room temperature, a new finding for this type of device. The results also indicate that while pure spin currents are less sensitive to temperature variations, spin-polarized current switching by an external voltage is more efficient, due to a combination of the Rashba effect and a change in carrier mobility by a Fermi level shift.

Deep learning for registration of region of interest in consecutive wireless capsule endoscopy frames

BACKGROUND AND OBJECTIVE

Functional gastrointestinal disorders (FGIDs) are reported as worldwide gastrointestinal (GI) diseases. GI motility assessment can assist the diagnosis of patients with intestine motility dysfunction. Wireless capsule endoscopy (WCE) can acquire images in the gastrointestinal (GI) tract including the small intestine where other conventional endoscopes cannot penetrate, and WCE images can reveal GI motility. To generally analyze WCE frames, the high-precision registration of consecutive WCE frames is an absolute necessity. It is difficult and meaningless to register entire WCE frames on a pixel level due to the unpredictable and massive non-rigid deformation between consecutive frames, the low quality of imaging and the complex intestinal environment. Thus, the registration of region of interest (ROI) functioning in a feature level has more significance than entire frame registration.

METHODS

In this paper we present Timecylce-WCE, an end-to-end automatic registration approach of ROIs on WCE images. The clinicians can determine a ROI by drawing a bounding box in any WCE frame to be registered. This proposed approach is based on a deep-learning model of time-consistency in recurrent-registering, skip-registering and self-registering cycle, and it is fully unsupervised without any label. We incorporate the global correlation map with the local correlation map in matching the features, and a novel overall loss function is designed to enable the convergence of the model. As the output, a thin-plate spline (TPS) transformed region in the template frame is highly aligned with the query ROI in a finer-grained level. To the best of our knowledge this is the first time that a deep-learning-based registration method is proposed for WCE imaging motion.

RESULTS

To highlight the effectiveness of the proposed approach, our proposed method is compared with the existing non-deep-learning methods and tested in a validation dataset with labeled matching points. The presented method resulted in the best PCK@10 (Percentage of Correct Key-points, i.e., the predicted and the true joint is within the threshold - 10 pixels) of 66.49%. We also demonstrate that variants of design improved registration accuracy.

CONCLUSIONS

From the experimental analysis, it is clear that our proposed method outperforms the other existing methods. This lays the groundwork for subsequent studies, such as GI motility assessment, and WCE image synthesis.

[Analysis of families with fetal congenital abnormalities but negative prenatal diagnosis by whole exome sequencing]

Objective: To evaluate the value of whole exome sequencing (WES) in prenatal clinical application. Methods: A total of 1 152 cases of congenital abnormal [including structural malformation, nuchal translucency (NT) thickening and intrauterine growth restriction] with traditional prenatal diagnosis [including G-band karyotype analysis and chromosome microarray analysis (CMA)] negative were analyzed. The congenital abnormal fetuses were divided into retrospective group and prospective group according to the time of WES detection, that is whether the pregnancy termination or not. According to the specific location of fetal malformation and their family history, the cohort was divided into subgroups. The clinical prognosis of all fetuses were followed up, and the effect of WES test results on pregnancy decision-making and clinical intervention were analyzed. According to the follow-up results, the data of fetuses with new phenotypes in the third trimester or after birth were re-analyzed. Results: Among 1 152 families who received WES, 5 families were excluded because of nonbiological parents. Among the remaining 1 147 families, 152 fetuses obtained positive diagnosis (13.3%,152/1 147), including 74 fetuses in the retrospective group (16.1%,74/460) and 78 fetuses in the prospective group (11.4%,78/687). In fetuses with negative CMA and G-band karyotype analysis results but new phenotypes in the third trimester or after birth, the positive rate by WES data re-analysis was 4.9% (8/163). A total of 34 (21.3%, 34/160) fetuses were directly affected by the corresponding positive molecular diagnosis. Among 68 cases of live births with diagnostic variation grade 4, 29 cases (42.7%, 29/68) received appropriate medical intervention through rapid review of WES results. Conclusions: WES could increase the detection rate of abnormal fetuses with negative G-banding karyotype analysis and CMA by 13.3%. Prenatal WES could guide pregnancy decision-making and early clinical intervention. It might be an effective strategy to pay attention to the special follow-up of the third trimester and postnatal fetus and to re-analyze the WES data.

Nicotinamide improves NAD+ levels to protect against acetaminophen-induced acute liver injury in mice

Acetaminophen (APAP) overdose causes acute liver injury (ALI). Nicotinamide adenine dinucleotide (NAD) is an essential coenzyme, and NAD⁺ is oxidized type which synthesized from nicotinamide (NAM). The present study aimed to investigate the role of NAD⁺ in ALI and protective property of NAM. The mice were subjected to different doses APAP. After 8 hours, the serum activities of alaninetransaminase (ALT) and aspartate aminotransferase (AST), the hepatic NAD⁺ level and nicotinamide phosphoribosyltransferase (NAMPT) expression were determined. Then, the mice were pretreated with NAM (800 mg/kg), the hepatoprotective effects and the key antioxidative molecules were evaluated. Our findings indicated that APAP resulted in remarkable NAD⁺ depletion in a dose-dependent manner accompanied by NAMPT downregulation, and NAM pretreatment significantly elevated the NAD⁺ decline due to upregulation of NAMPT. Moreover, the downregulated Kelch-like ECH-associated protein-1 (Keap1), upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and its translocation activation after NAM administration were confirmed, which were in accordance with improved superoxide dismutase (SOD) and glutathione (GSH) levels. Finally, NAM dramatically exhibited hepatoprotective effects by reducing the liver index and necrotic area. This study has suggested that APAP impairs liver NAD⁺ level and NAM is able to improve hepatic NAD⁺ to activate antioxidant pathway against APAP-induced ALI.

MiR-449b-5p inhibits human glioblastoma cell proliferation by inactivating WNT2B/Wnt/β-catenin signaling pathway

OBJECTIVE

As the most common primary brain cancer in adults, glioblastoma shows an extremely poor prognosis. Glioblastoma-associated deaths account for approximately 3%-4% of all malignancy-associated deaths. Numerous microRNAs (miRNAs) play important roles in the occurrence and progression of solid tumors. Herein, identifying functional miRNAs and the central molecular mechanisms would provide novel proofs for the development of targeted cancer therapies. In this study, we described the role of miR-449b-5p in restraining ontogenesis and progression of glioblastoma.

PATIENTS AND METHODS

Human glioblastoma tissues were provided by our hospital. Human U251 glioblastoma cells were infected with lentivirus induced miR-449b-5p mimics or miR-449b-5p siRNA. Real-time qPCR was carried out to determine miRNA expression. Tumor spheres formation, MTT assay, and BrdU cell proliferation assay were used to evaluate the growth ability of U251 cells. Western blot assay was performed to measure protein expression. ChIP was used to detect the capacity of β-catenin to recruit its downstream genes. Dual-Luciferase assay was conducted to detect the ability of miR-449b-5p to regulate the 3'UTR (untranslated regions) of WNT2B. TOP/FOP ratio was used to evaluate the activity of Wnt/β-catenin signaling pathway.

RESULTS

Down-regulation of miR-449b-5p expression was found in both human glioblastoma tissues and cell lines, which was negatively associated with the clinical stages. Up-regulation of miR-449b-5p inhibited tumor spheres formation, cell viability and proliferation ability of glioblastoma cells. The expression levels of WNT2B and nuclear β-catenin were negatively associated with miR-449b-5p levels in glioblastoma cells. MiR-449b-5p inhibited Wnt/β-catenin signaling by targeting WNT2B.

CONCLUSIONS

MiR-449b-5p acts as a tumor suppressor and retards the oncogenesis of glioblastoma, which is achieved via inactivation of Wnt/β-catenin signaling by directly targeting WNT2B.

Effect of computer-assisted design and manufacturing cutting and drilling guides accompanied with pre-bent titanium plates on the correction of skeletal class II malocclusion: a randomized controlled trial

This study was performed to assess the effect of correcting skeletal class II malocclusion based on the application of computer-assisted design and manufacturing (CAD/CAM) cutting and drilling guides accompanied with pre-bent titanium plates. Fifty patients with skeletal class II malocclusion were recruited into this prospective randomized controlled clinical trial and assigned to two groups. Patients underwent bilateral sagittal split ramus osteotomy directed by CAD/CAM cutting and drilling guides accompanied with pre-bent titanium plates (group A) or CAD/CAM splints (group B). Postoperative assessments were performed. Differences between the virtually simulated and postoperative models were measured. Patients in both groups had a satisfactory occlusion and appearance. More accurate repositioning of the proximal segment was found in group A than in group B when comparing linear and angular differences to reference planes; however, no significant difference was revealed for the distal segment. In conclusion, CAD/CAM cutting and drilling guides with pre-bent titanium plates can provide considerable surgical accuracy for the positional control of the proximal segments in bilateral sagittal split ramus osteotomy for the correction of skeletal class II deformities.

Efficacy and safety of modified Yupingfeng formula in treating allergic rhinitis: A protocol for systematic review and meta analysis

BACKGROUND

Allergic rhinitis (AR) is a non-infectious chronic nasal mucosal disease mediated mainly by IgE, which affects 40% of the global population and has a recurrence rate of more than 50%. The modified Yupingfeng formula (MYPFF) is widely used in the treatment of allergic rhinitis in China. However, there is no evidence-based medical evidence for the efficacy and safety of MYPFF in the treatment of allergic rhinitis.

METHODS

Database as China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Scientific Journal Database (VIP database), Wan-Fang Database, the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, and Web of Science will be searched for relevant literature from inception to September 2020. Data extraction will be performed on the obtained literature. Then RevMan V.5.3 will be used for the assessment of the risk of bias and data synthesis.

RESULTS

The results will be published in a peer-reviewed journal.

CONCLUSION

The conclusion of the study will provide an evidence to efficacy and safety of MYPFF in treating allergic rhinitis, which will be of significant meaning for further research and clinical practice.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/RV9P4.

Effects of houttuynia cordata thunb. on rhinosinusitis by nasal irrigation: A protocol for systematic review and meta-analysis

BACKGROUND

The herba Houttuynia cordata Thunb. (HC) has anti-inflammatory, antibacterial and antiviral effects. Through nasal irrigation, the related preparation of HC is beneficial for treating rhinosinusitis or promoting recovery after an endoscopic sinus surgery. However, it remains controversial whether nasal irrigation with HC preparation can provide evidence-based clinical benefits for rhinosinusitis patients.

METHODS

With reference to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 8 databases are perused to perform a methodical investigation of nasal irrigation with HC preparation and health-related results amongst rhinosinusitis patients. The main research purpose is to determine the influence of PRISMA standards on medical results pertaining to rhinosinusitis patients, including quantitative symptom recording and effective rate. With reference to the Cochrane Handbook, quality assessment of qualified papers is conducted using the Cochrane Risk Assessment Tool.

RESULTS

The results will be publicised through a peer-reviewed journal publication.

CONCLUSION

The results of the systematic review will summarise evidences for the efficacy of nasal irrigation with HC preparation in rhinosinusitis treatment.

ETHICS AND DISSEMINATION

Since this study involves a methodical investigation of issued medical papers, ethical authorisation and informed patient consent are not necessary.

Is nasal septal suturing an alternative technique to nasal packing?: A protocol for systematic review and meta-analysis

BACKGROUND

Nasal septal suturing is a commonly used alternative treatment to nasal packing after septoplasty. Besides alleviating postoperative discomfort, extensive studies have shown that nasal septal suturing is more effective than nasal packing. However, its clinical benefits remain controversial.

METHODS

We will perform a systematic review of nasal packings effect-related outcome in comparison to nasal septum suture among septoplasty patients by searching 8 databases, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). All eligible studies will be screened against the inclusion and exclusion criteria. Two independent reviewers will extract the data. Moreover, Review Manage 5.3 will be used for quality assessment and data analysis. Then, the random effects model or fixed effects model will be applied according to the heterogeneity. In conformity with the GRADE criteria, the merits of the evidence and recommended strength will be assessed.

RESULTS

This protocol will guide subsequent systematic reviews and meta-analyses. The differences in efficacy between nasal septal suturing and nasal packing after septoplasty will be evaluated in terms of efficiency, adverse reaction, comfort degree, and other factors.

CONCLUSION

This proposed study will explore the possibility of adopting nasal septal suturing as an alternative to nasal packing after septoplasty. OSF REGISTRATION NUMBER:: doi: 10.17605/OSF.IO/WF3GX.

[Long-term outcome of childhood T-cell acute lymphoblastic leukemia treated with modified national protocol of childhood leukemia in China-acute lymphoblastic leukemia 2008]

Objective: To analyse the long-term efficacy in childhood T-cell acute lymphoblastic leukemia (T-ALL) cases enrolled in the national protocol of childhood leukemia in China-acute lymphoblastic leukemia (NPCLC-ALL) 2008. Methods: Clinical data of 96 patients diagnosed as T-ALL and treated with NPCLC-ALL2008 protocol between January 2009 and December 2017 in the Department of Hematology-Oncology, the Children's Hospital, Zhejiang University School of Medicine were analyzed retrospectively. Predictive value of minimal residual disease (MRD) monitored by flow cytometry was analyzed. Kaplan-Meier method was used for long-term survival analysis. Results: A total of 96 evaluable patients with newly diagnosed T-ALL were analysed, including 72 males and 24 females. The age was 9.5 (ranged from 1.0 to 16.0) years. The follow-up time was 5.7 (ranged from 1.0 to 9.7) years. Among 96 patients, 92 (96%) achieved complete remission. The 5-year event free survival (EFS) and overall survival (OS) rates were (61±6) % and (70±5) %, respectively. Relapse occurred in 18 cases and the 5-year cumulative incidence of relapse was (27±6) %. Twenty-four patients died. The 5-year OS rates of patients with MRD>5% on day 15 of induction therapy was significantly worse than those with MRD≤5% ((60±12) % vs. (72±6) %, χ(2)=3.904, P=0.048) . The 5-year EFS and OS rates were obviously lower in patients with MRD>10% before the consolidation therapy ((50±35) %). The 5-year OS rates of patients with relapsed disease was significantly worse than those without ((26±13) % vs. (81±5) %, χ(2)=18.411, P<0.01). The earlier the relapse, the worse the prognosis. The 5-year OS rates for patients relapsed within 6 months, within 3 years and more than 3 years, were (25±22) %, (30±14) % and (50±35) % respectively (χ(2)=13.207, P<0.01). Conclusions: NPCLC-ALL2008 protocol is effective for childhood T-ALL. The MRD guided accurate risk stratification and individualized treatment can reduce the relapse and improve the survival rate of pediatric T-ALL.

AXIN2 gene silencing reduces apoptosis through regulating mitochondria-associated apoptosis signaling pathway and enhances proliferation of ESCs by modulating Wnt/β-catenin signaling pathway

OBJECTIVE

Embryonic stem cells (ESCs) mainly originate from totipotent cells in early-stage of mammalian embryo and could proliferate in a manner of un-limitation. This study aimed to investigate roles of Axin2 in proliferation of ESCs and explore the associated mechanisms.

MATERIALS AND METHODS

Axis inhibition protein 2 (AXIN2) over-expression (LV5-AXIN2) and AXIN2 RNA interfere (LV3-AXIN2-RNAi) vectors were structured and transfected into H9 cells. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) was used to evaluate cell proliferative activity. Flow cytometry analysis was employed to measure apoptosis of H9 cells. AXIN2, β-catenin, transcription factor 4 (TCF4), c-myc, c-jun and Cyclin D mRNA levels and protein expressions were determined using quantitative real-time PCR (qRT-PCR) and Western blotting assay.

RESULTS

LV5-AXIN2 and LV3-AXIN2-RNAi were successfully structured with higher transfecting efficacy. AXIN2 gene silencing remarkably increased proliferative activity and AXIN2 treatment significantly induced apoptosis of H9 cells, comparing with blank vector group (p<0.05). AXIN2 gene silencing significantly enhanced B-cell lymphoma-2 (Bcl-2) expression and remarkably inhibited cleaved caspase-3 expression comparing to that in blank vector group (p<0.05). AXIN2-RNAi treatment significantly enhanced and AXIN2 over-expression significantly reduced β-catenin and TCF4 expression, comparing to that in blank vector group (p<0.05). AXIN2 gene silence activated down-stream molecules of Wnt/β-catenin signaling pathway, including c-jun, c-myc, and Cyclin D1 (p<0.05).

CONCLUSIONS

AXIN2 gene silencing reduced apoptosis by regulating mitochondria-associated apoptosis signaling pathway and enhanced proliferation by modulating molecules in Wnt/β-catenin signaling pathway. Therefore, targeting of aberrant apoptosis and AXIN2 might be a novel clinical strategy to inhibit aging and enhance self-renewal of ESCs.

Impacts of florfenicol on the microbiota landscape and resistome as revealed by metagenomic analysis

BACKGROUND

Drug-resistant fish pathogens can cause significant economic loss to fish farmers. Since 2012, florfenicol has become an approved drug for treating both septicemia and columnaris diseases in freshwater fish. Due to the limited drug options available for aquaculture, the impact of the therapeutical florfenicol treatment on the microbiota landscape as well as the resistome present in the aquaculture farm environment needs to be evaluated.

RESULTS

Time-series metagenomic analyses were conducted to the aquatic microbiota present in the tank-based catfish production systems, in which catfish received standard therapeutic 10-day florfenicol treatment following the federal veterinary regulations. Results showed that the florfenicol treatment shifted the structure of the microbiota and reduced the biodiversity of it by acting as a strong stressor. Planctomycetes, Chloroflexi, and 13 other phyla were susceptible to the florfenicol treatment and their abundance was inhibited by the treatment. In contrast, the abundance of several bacteria belonging to the Proteobacteria, Bacteroidetes, Actinobacteria, and Verrucomicrobia phyla increased. These bacteria with increased abundance either harbor florfenicol-resistant genes (FRGs) or had beneficial mutations. The florfenicol treatment promoted the proliferation of florfenicol-resistant genes. The copy number of phenicol-specific resistance genes as well as multiple classes of antibiotic-resistant genes (ARGs) exhibited strong correlations across different genetic exchange communities (p < 0.05), indicating the horizontal transfer of florfenicol-resistant genes among these bacterial species or genera. Florfenicol treatment also induced mutation-driven resistance. Significant changes in single-nucleotide polymorphism (SNP) allele frequencies were observed in membrane transporters, genes involved in recombination, and in genes with primary functions of a resistance phenotype.

CONCLUSIONS

The therapeutical level of florfenicol treatment significantly altered the microbiome and resistome present in catfish tanks. Both intra-population and inter-population horizontal ARG transfer was observed, with the intra-population transfer being more common. The oxazolidinone/phenicol-resistant gene optrA was the most prevalent transferred ARG. In addition to horizontal gene transfer, bacteria could also acquire florfenicol resistance by regulating the innate efflux systems via mutations. The observations made by this study are of great importance for guiding the strategic use of florfenicol, thus preventing the formation, persistence, and spreading of florfenicol-resistant bacteria and resistance genes in aquaculture.

Adaptive regulation of detoxification enzymes in Helicoverpa armigera to different host plants

Cotton plants produce gossypol as a major secondary metabolite to resist insect herbivores and pathogens. Helicoverpa armigera may employ multigene families of detoxification enzymes to deal with this metabolite. So far, the strength of the transcriptional response to gossypol detoxification in the cotton bollworms remains poorly understood. Here, we investigated the genomewide transcriptional changes that occur in cotton bollworm larvae after one generation feeding on various host plants (cotton, corn, soybean and chili) or an artificial diet. Six genes potentially involved in detoxification of xenobiotics were highly upregulated in bollworms fed on cotton, and the expression of five of these differed significantly in insects that fed on gossypol diet compared with the artificial diet. When these six genes were downregulated using RNA interference, downregulation only of CYP4L11, CYP6AB9 and CCE001b led to reduced growth of bollworm larvae feeding on gossypol diets. These data suggest that the three genes are involved in response of H. armigera to gossypol of cotton. Our results proved that H. armigera may have a broad mechanism for gossypol detoxification.

[Clinical analysis of Langerhans cell histiocytosis originating in the base of nasal skull]

Objective:To summarize the clinical features, diagnosis and treatment of Langerhans histiocytosis（LCH） which first appeared in the nasal skull base. Method:Ten cases of LCH with nasal and skull base symptoms were analyzed retrospectively. The clinical characteristics of LCH with nasal and skull base symptoms were summarized. The correlation of other systems involved in LCH was analyzed. Result:Among the 10 patients, the youngest was 1 year and 5 months, and the oldest was 8 years, the average age was 3 years. The main imaging manifestations were osteolytic changes and soft tissue invasion. Seven patients were monofocal and three patients were multifocal. For localized lesions, radical resection and follow-up chemotherapy were performed, and conservative treatment was performed for patients with multiple system involvement and obvious systemic symptoms. Eight patients survived, 2 died. Conclusion:LCH occurs frequently in children and has certain clinical characteristics. Single system and single lesion surgery have a better therapeutic effect, and can achieve a greater survival rate with follow-up chemotherapy.

Partially Covered Versus Uncovered Self-Expandable Metal Stents: Coating Nor Diameter Affect Clinical Outcomes

INTRODUCTION

Jaundice is a common initial presentation of malignant biliary stricture. In patients with life expectancies that are greater than 3 months, self-expanding metal stents (SEMS) offer a larger diameter stent with longer patency and fewer complications compared to plastic stents. There have been conflicting results in the published literature as to efficacy and safety between the various SEMS types and diameters. We compared stent coating (PCSEMS vs USEMS) and diameter on clinical outcomes regarding management of malignant biliary obstruction.

METHODS

A retrospective cohort study was conducted using a database of consecutive patients who underwent an ERCP with biliary SEMS placement (only 8 and 10 mm) between 2009 and 2017.

RESULTS

In total, 278 patients who had SEMS at ERCP for malignant biliary obstruction were included (213 PCSEMS vs 65 USEMS). The groups were demographically evenly matched. Clinical success rates and patency duration were not statistically significant between PCSEMS and USEMS (98.1% vs 95.5%, P = 0.36, and 302.5 vs 225.5 days, P = 0.72, respectively). Adverse event rates were similar between both PCSEMS and USEMS with regard to overall adverse events. Stent diameter did not have an impact on overall clinical success (98.9% vs 95.3%, P = 0.11) or patency duration (239 days vs 336 days, P = 0.51).

CONCLUSIONS

Our comparison of PCSEMS versus USEMS and 8 mm versus 10 mm showed no difference in clinical efficacy or adverse events between the two SEMS coatings and diameter, illustrating that coating and size do not matter in regard to stent choice, despite prior suggestive data.

Effect of infectious bursal disease virus infection on energy metabolism in embryonic chicken livers

1. The purpose of this study was to investigate ATP levels and the activities of important enzymes involved in glycolysis and TCA cycle in livers of embryonated chicken eggs infected by infectious bursal disease virus (IBDV).2. Embryonated chicken eggs (9 days) were randomly divided into two groups (50 eggs per group). The first group was inoculated with a very virulent IBDV (vvIBDV) isolate into the chorioallantoic membrane. The second group was maintained as uninfected control eggs and inoculated with physiological saline. Embryo survival was assessed daily, and six embryos were sacrificed at 24, 48, 72, 96, and 120 hpi for examining livers. Viral loads in the livers were evaluated by qRT-PCR. A comparative analysis of markers associated with the regulation of energy metabolism across several functional classes (ATP, pyruvic and lactic acids, mitochondrial protein, NAD+/NADH ratios, and enolase, lactic acid dehydrogenase and the respiratory chain complex I activities) were examined in the context of IBDV infection.3. The results indicated that increases in the enzymatic activities associated with glycolytic metabolism in turn affected the synthesis and cytoplasmic concentrations of ATP at early timepoints in infected chicken embryos. Subsequently, energy metabolism was inhibited through the pathological perturbations of metabolic enzymes and mitochondrial damage, as inferred from reduced ATP generation.4. These results suggested impaired bioenergetics, which may lead to liver dysfunction consequent to IBDV infection, contributing to the disease pathogenesis.

Relative efficacy and safety of early lactate clearance-guided therapy resuscitation in patients with sepsis: A meta-analysis

OBJECTIVE

Compelling evidence has shown that aggressive resuscitation bundles are one of the cornerstones of the successful treatment of patients with sepsis. Recent studies suggest that lactate normalization during resuscitation is a more powerful indicator of resuscitative adequacy; however, early lactate clearance-guided therapy is still not recommended. We performed this meta-analysis to evaluate the effect of early lactate clearance-directed therapy as a potentially more effective resuscitation target.

METHODS

Studies were identified using PubMed, Embase, and the Cochrane Library without region, publication type, or language restrictions. Randomized trials were included when they compared the efficacy and safety of lactate clearance-guided resuscitation versus central venous oxygen saturation (ScvO2)-guided therapy. The primary outcome was mortality, and the secondary outcomes were intensive care unit (ICU) stay, length of hospital stay, mechanical ventilation time, Acute Physiology and Chronic Health Evaluation-II (APACHE-II) score, and Sepsis-related Organ Failure Assessment (SOFA) score.

RESULTS

Seven randomized controlled trials encompassing 1301 cases were reviewed. Compared with guided ScvO2 therapy, early lactate clearance-directed therapy was associated with decreased in-hospital mortality (relative ratio [RR] 0.68, 95% confidence interval [CI] 0.56 to 0.82), shorter ICU stay (mean difference [MD] -1.64 days, 95% CI -3.23 to -0.05), shorter mechanical ventilation time (MD -10.22 hours, 95% CI -15.94 to -4.5), and lower APACHE-II scores (MD -4.47, 95% CI -7.25 to -1.69). However, patients undergoing early lactate clearance-guided therapy had similar lengths of hospital stay and similar SOFA scores.

CONCLUSIONS

As a specific indicator of resuscitation outcome, lactate clearance alone is superior to ScvO2 alone during a standard resuscitation paradigm. The optimal or desired rate of lactate clearance is still a contentious area. To guide resuscitation and normalize lactate levels in patients, repeating lactate measurements every 2 hours until the patient has met a lactate clearance of 10% or greater may be helpful.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42018100515.

The Impact of Cryopreservation-Thawing Conditions on Umbilical Cord Blood Quality and Transplantation Outcomes

BACKGROUND

Cord blood units (CBUs) go through the cryopreservation-thawing process for storage before use in transplantation. The differences in the cryopreservation-thawing process affect the quality of CBUs. The effects of the cryopreservation-thawing process on the final outcomes of CBU transplantation has not been defined well.

OBJECTIVE

To study the impact of differences in the cryopreservation-thawing process on the quality of CBUs and the final clinical outcomes of transplantation.

MATERIALS AND METHODS

The differences in cryopreservation-thawing conditions were analyzed to determine their effect on the quality and clinical outcomes of transplanted CBUs. CBUs were detected using the same reagents, instruments and methods for minimizing experimental errors.

RESULTS

The differences in the cryopreservation-thawing process did not change cell survival, TNCC recovery (CD34⁺ and CFUs), the implantation rates and recovery time of neutrophils/100-day platelets.

CONCLUSION

The present study shows that the differences in the cryopreservation-thawing conditions do not influence the quality and transplantation outcomes of CBUs.

[Chorionic villus cell culture and karyotype analysis in 1 983 cases of spontaneous miscarriage]

Objective: To investigate the relationship between spontaneous miscarriage and embryonic chromosome abnormalities, and to evaluate the clinical application of karyotype analysis by chorionic villus cell culture. Methods: The chorionic villus karyotype of 1 983 cases of miscarriage from January 2010 to July 2016 in Guangzhou Women and Children's Mecical Center were analyzed retrospectively. The miscarried chorionic villi were obtained by curettage under sterilized condition. The chromosome specimens were prepared after chorionic villus cell culture. Karyotype analysis was performed by G-banding technique. Results: In the 1 983 samples, successful karyotype analysis was performed in 1 770 cases, with the successful rate of 89.98%. Chromosomal abnormalities were found in 1 038 cases (58.64%, 1 038/1 770). Chromosomal structural abnormalities were found in 37 cases. The numeral abnormalities were more common than structural abnormalities, and most of the numeral abnormalities were aneupoidies. In turn, they were trisomy 16, 45,X, trisomy 22, trisomy 2, trisomy 21, trisomy 15. The most common structural abnormality was balanced translocation, including Robersonian translocation. Female embryoes accounted for 61.02% (1 080/1 770) miscarriages and for 57.4%(596/1 770) of chromosomal abnormalities, while male embroyes acoounted for 61.02% (1 080/1 770) , 57.4% (596/1 770) respectively. The proportion of female embryoes was higher than male embryoes. The median age of the patients was 30 years old (16-46 years old) . As the maternal age increased, the proportion chromosomal abnormalities increased. The incidence of chromosomal abnormalities in the advanced age group (≥35 years) was 68.38% (240/351) , which was significantly higher than that in the younger group (56.24%, 798/1 419; χ(2)=17.10, P<0.01). Conclusions: Embryonic chromosomal abnormalities are the most common cause of early spontaneous miscarriage. The abnormalities centralize in some karyotypes. There is certain relationship between maternal age and the incidence of miscarriage, as well as the embryonic gender. Chorionic villus cell culture and karyotype analysis are helpful in finding the cause of miscarriage and counsel the patients.

Resting-State Functional MRI: Everything That Nonexperts Have Always Wanted to Know

Resting-state fMRI was first described by Biswal et al in 1995 and has since then been widely used in both healthy subjects and patients with various neurologic, neurosurgical, and psychiatric disorders. As opposed to paradigm- or task-based functional MR imaging, resting-state fMRI does not require subjects to perform any specific task. The low-frequency oscillations of the resting-state fMRI signal have been shown to relate to the spontaneous neural activity. There are many ways to analyze resting-state fMRI data. In this review article, we will briefly describe a few of these and highlight the advantages and limitations of each. This description is to facilitate the adoption and use of resting-state fMRI in the clinical setting, helping neuroradiologists become familiar with these techniques and applying them for the care of patients with neurologic and psychiatric diseases.

Lapine periodontal ligament stem cells for musculoskeletal research in preclinical animal trials

Background

Human periodontal ligament stem cells (hPDLSCs) have been shown to be a reliable source of mesenchymal stem cells (MSCs). On the other hand, rabbits have been commonly used in preclinical trials for musculoskeletal research. However, there is a lack of sufficient data on using rabbit periodontal ligament stem cells (rPDLSCs) for regenerative dentistry. This study, for the first time, comprehensively compared rPDLSCs against hPDLSCs in terms of clonogenicity, growth potential, multi-differential capacity and surface antigens.

Methods

Periodontal ligament (PDL) was obtained from the rabbit and human teeth. rPDL and hPDL cells were isolated from PDL using enzymatic digestion method. After culturing for 2 weeks, the cells were first analyzed microscopically. STRO-1⁺CD146⁺ PDLSCs were then sorted from PDL cells by fluorescence-activated cell sorting (FACS) followed by examination of CD34, CD45, CD90, vimentin and desmin markers. The cells were also evaluated by immunohistocytochemical and multi-differentiation potential tests. The clonogenicity and growth of PDL cells were analyzed by Independent T test and 2-way repeated measures ANOVA respectively.

Results

rPDL cells were broader and less elongated as compared to hPDL cells. STRO-1⁺CD146⁺ hPDLSCs were isolated from hPDL cells but not from the rPDL cells. Therefore, heterogeneous population of rabbit and human PDL cells were subsequently used for latter comparative studies. FACS analysis and immunohistocytochemistry revealed that rPDL cells were partially positive for STRO-1 as compared to hPDL cells. Furthermore, both rPDL cells and hPDL cells were positive for CD146, CD90, vimentin, and desmin, while negative for CD34 and CD45. No difference in clonogenicity between rPDL and hPDL cells was found (p > 0.05). The proliferative potential of rPDL cells displayed significantly slower growth as compared to hPDL cells (p < 0.05). Osteogenic, adipogenic, and chondrogenic differentiation potential was comparatively less in rPDL cells than that of hPDL cells, but the neurogenic differential potential was similar.

Conclusion

Although rPDL cells manifested variable differences in expression of stem cell markers and multi-differential potential as compared to hPDL cells, they demonstrated the attributes of stemness. Further studies are also required to validate if the regenerative potential of rPDL cells is similar to rPDLSCs.