Global distribution, cross-species transmission, and receptor binding of canine parvovirus-2: Risks and implications for humans

For canine parvovirus -2 (CPV-2), a zoonotic virus capable of cross-species transmission in animals, the amino acid changes of capsid protein VP2 are key factors when binding to other species' transferrin receptors (TfR). CPV-2 variants can spread from felines and canines, for example, to Carnivora, Artiodactyla, and Pholidota species, and CPV-2c variants are essential to spread from Carnivora to Artiodactyla and Pholidota species in particular. In our study, a CPV-2a variant maintained a relatively stable trend, and the proportion of CPV-2c gradually rose from 1980 to 2021. The VP2 amino acid sequence analysis showed that five amino acid mutations at 426E/D, 305H/D, and 297S may be necessary for the virus to bind to different host receptors. Meanwhile, receptor-binding loop regions and amino acid sites 87 L, 93 N, 232I, and 305Y were associated with CPV-2 cross-species transmission. The homology of TfRs in different hosts infected with CPV-2 ranged from 77.2 % to 99.0 %, and from pig to feline, canine, and humans was 80.7 %, 80.4 %, and 77.2 %, respectively. The amino acid residues of TfRs involved in the viral binding in those hosts are highly conserved, which suggests that CPV-2 may be capable of pig-to-human transmission. Our analysis of the origin, evolutionary trend, cross-species transmission dynamics, and genetic characteristics of CPV-2 when binding to host receptors provides a theoretical basis for further research on CPV-2's mechanism of cross-species transmission and for establishing an early warning and monitoring mechanism for the possible threat of CPV-2 to animal-human public security.

[Effects of cerium oxide nanoenzyme-gelatin methacrylate anhydride hydrogel in the repair of infected full-thickness skin defect wounds in mice]

Objective: To investigate the effects of cerium oxide nanoenzyme-gelatin methacrylate anhydride (GelMA) hydrogel (hereinafter referred to as composite hydrogel) in the repair of infected full-thickness skin defect wounds in mice. Methods: This study was an experimental study. Cerium oxide nanoenzyme with a particle size of (116±9) nm was prepared by hydrothermal method, and GelMA hydrogel with porous network structure and good gelling performance was also prepared. The 25 μg/mL cerium oxide nanoenzyme which could significantly promote the proliferation of human skin fibroblasts and had high superoxide dismutase activity was screened out. It was added to GelMA hydrogel to prepare composite hydrogel. The percentage of cerium oxide nanoenzyme released from the composite hydrogel was calculated after immersing it in phosphate buffer solution (PBS) for 3 and 7 d. The red blood cell suspension of mice was divided into PBS group, Triton X-100 group, cerium oxide nanoenzyme group, GelMA hydrogel group, and composite hydrogel group, which were treated with corresponding solution. The hemolysis of red blood cells was detected by microplate reader after 1 h of treatment. The bacterial concentrations of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli were determined after being cultured with PBS, cerium oxide nanoenzyme, GelMA hydrogel, and composite hydrogel for 2 h. The sample size in all above experiments was 3. Twenty-four 8-week-old male BALB/c mice were taken, and a full-thickness skin defect wound was prepared in the symmetrical position on the back and infected with MRSA. The mice were divided into control group without any drug intervention, and cerium oxide nanoenzyme group, GelMA hydrogel group, and composite hydrogel group applied with corresponding solution, with 6 mice in each group. The wound healing was observed on 3, 7, and 14 d after injury, and the remaining wound areas on 3 and 7 d after injury were measured (the sample size was 5). The concentration of MRSA in the wound exudation of mice on 3 d after injury was measured (the sample size was 3), and the blood flow perfusion in the wound of mice on 5 d after injury was observed using a laser speckle flow imaging system (the sample size was 6). On 14 d after injury, the wound tissue of mice was collected for hematoxylin-eosin staining to observe the newly formed epithelium and for Masson staining to observe the collagen situation (the sample size was both 3). Results: After immersion for 3 and 7 d, the release percentages of cerium oxide nanoenzyme in the composite hydrogel were about 39% and 75%, respectively. After 1 h of treatment, compared with that in Triton X-100 group, the hemolysis of red blood cells in PBS group, GelMA hydrogel group, cerium oxide nanoenzyme group, and composite hydrogel group was significantly decreased (P<0.05). Compared with that cultured with PBS, the concentrations of MRSA and Escherichia coli cultured with cerium oxide nanoenzyme, GelMA hydrogel, and composite hydrogel for 2 h were significantly decreased (P<0.05). The wounds of mice in the four groups were gradually healed from 3 to 14 d after injury, and the wounds of mice in composite hydrogel group were all healed on 14 d after injury. On 3 and 7 d after injury, the remaining wound areas of mice in composite hydrogel group were (29±3) and (13±5) mm2, respectively, which were significantly smaller than (56±12) and (46±10) mm2 in control group and (51±7) and (38±8) mm2 in cerium oxide nanoenzyme group (with P values all <0.05), but was similar to (41±5) and (24±9) mm2 in GelMA hydrogel group (with P values both >0.05). On 3 d after injury, the concentration of MRSA on the wound of mice in composite hydrogel group was significantly lower than that in control group, cerium oxide nanoenzyme group, and GelMA hydrogel group, respectively (with P values all <0.05). On 5 d after injury, the volume of blood perfusion in the wound of mice in composite hydrogel group was significantly higher than that in control group, cerium oxide nanoenzyme group, and GelMA hydrogel group, respectively (P<0.05). On 14 d after injury, the wound of mice in composite hydrogel group basically completed epithelization, and the epithelization was significantly better than that in the other three groups. Compared with that in the other three groups, the content of collagen in the wound of mice in composite hydrogel group was significantly increased, and the arrangement was also more orderly. Conclusions: The composite hydrogel has good biocompatibility and antibacterial effect in vivo and in vitro. It can continuously sustained release cerium oxide nanoenzyme, improve wound blood perfusion in the early stage, and promote wound re-epithelialization and collagen synthesis, therefore promoting the healing of infected full-thickness skin defect wounds in mice.

[Research progress of long-chain non-coding RNA in lipid metabolism reprogramming in primary hepatocellular carcinoma]

Hepatocellular carcinoma (HCC) is the most common liver malignant tumor with complex pathogenesis and a poor prognosis. Metabolic reprogramming has been recognized as one of the important cancer markers, and the liver, as an important organ for lipid metabolism in the human body, plays an important role in the process of the occurrence and development of HCC. More and more evidence shows that long-chain non-coding RNA (lncRNA) can influence the lipid metabolism process by regulating key enzymes and transcription factors, as well as being involved in the occurrence and development of HCC. Therefore, explicating the mechanism of lncRNA in lipid metabolism reprogramming is conducive to providing new targets and strategies for the diagnosis and treatment and improving the prognosis of HCC patients. This article summarizes the latest research progress on the involvement of lncRNA in the reprogramming process of HCC lipid metabolism.

A Novel Bacillus Velezensis for Efficient Degradation of Zearalenone

Zearalenone (ZEN) is considered one of the most serious mycotoxins contaminating grains and their by-products, causing significant economic losses in the feed and food industries. Biodegradation pathways are currently considered the most efficient solution to remove ZEN contamination from foods. However, low degradation rates and vulnerability to environmental impacts limit the application of biodegradation pathways. Therefore, the main research objective of this article was to screen strains that can efficiently degrade ZEN and survive under harsh conditions. This study successfully isolated a new strain L9 which can efficiently degrade ZEN from 108 food ingredients. The results of sequence alignment showed that L9 is Bacillus velezensis. Meanwhile, we found that the L9 degradation rate reached 91.14% at 24 h and confirmed that the primary degradation mechanism of this strain is biodegradation. The strain exhibits resistance to high temperature, acid, and 0.3% bile salts. The results of whole-genome sequencing analysis showed that, it is possible that the strain encodes the key enzyme, such as chitinase, carboxylesterases, and lactone hydrolase, that work together to degrade ZEN. In addition, 227 unique genes in this strain are primarily involved in its replication, recombination, repair, and protective mechanisms. In summary, we successfully excavated a ZEN-degrading, genetically distinct strain of Bacillus velezensis that provides a solid foundation for the detoxification of feed and food contamination in the natural environment.

Heat stress-associated changes in the intestinal barrier, inflammatory signals, and microbiome communities in dairy calves

Recent studies indicate that heat stress pathophysiology is associated with intestinal barrier dysfunction, local and systemic inflammation, and gut dysbiosis. However, inconclusive results and a poor description of tissue-specific changes must be addressed to identify potential intervention targets against heat stress illness in growing calves. Therefore, the objective of this study was to evaluate components of the intestinal barrier, pro- and anti-inflammatory signals, and microbiota community composition in Holstein bull calves exposed to heat stress. Animals (mean age = 12 wk old; mean body weight = 122 kg) penned individually in temperature-controlled rooms were assigned to (1) thermoneutral conditions (constant room temperature at 19.5°C) and restricted offer of feed (TNR, n = 8), or (2) heat stress conditions (cycles of room temperatures ranging from 20 to 37.8°C) along with ad libitum offer of feed (HS, n = 8) for 7 d. Upon treatment completion, sections of the jejunum, ileum, and colon were collected and snap-frozen immediately to evaluate gene and protein expression, cytokine concentrations, and myeloperoxidase activity. Digesta aliquots of the ileum, colon, and rectum were collected to assess bacterial communities. Plasma was harvested on d 2, 5, and 7 to determine cytokine concentrations. Overall, results showed a section-specific effect of HS on intestinal integrity. Jejunal mRNA expression of TJP1 was decreased by 70.9% in HS relative to TNR calves. In agreement, jejunal expression of heat shock transcription factor-1 protein, a known tight junction protein expression regulator, decreased by 48% in HS calves. Jejunal analyses showed that HS decreased concentrations of IL-1α by 36.6% and tended to decrease the concentration of IL-17A. Conversely, HS elicited a 3.5-fold increase in jejunal concentration of anti-inflammatory IL-36 receptor antagonist. Plasma analysis of pro-inflammatory cytokines showed that IL-6 decreased by 51% in HS relative to TNR calves. Heat stress alteration of the large intestine bacterial communities was characterized by increased genus Butyrivibrio_3, a known butyrate-producing organism, and changes in bacteria metabolism of energy and AA. A strong positive correlation between the rectal temperature and pro-inflammatory Eggerthii spp. was detected in HS calves. In conclusion, this work indicates that HS impairs the intestinal barrier function of jejunum. The pro- and anti-inflammatory signal changes may be part of a broader response to restore intestinal homeostasis in jejunum. The changes in large intestine bacterial communities favoring butyrate-producing organisms (e.g., Butyrivibrio spp.) may be part of a successful response to maintain the integrity of the colonic mucosa of HS calves. The alteration of intestinal homeostasis should be the target for heat stress therapies to restore biological functions, and, thus highlights the relevance of this work.

[Research progress of non-coding RNA-encoding polypeptides in primary hepatocellular carcinoma]

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, with rapid progression and a poor prognosis. More and more studies have shown that there are small open reading frames (sORFs) on the molecular sequences of a large number of non-coding RNAs (ncRNAs), which can encode conserved peptides that play an important role in controlling the occurrence and development of HCC. This article introduces the discovery, prediction, and validation methods of ncRNA-encoding polypeptides and reviews its research progress, with the aim of providing new targets and ideas for early-stage diagnosis, targeted therapy, and prognosis assessment of HCC.

A Cholecystokinin Analogue Ameliorates Cognitive Deficits and Regulates Mitochondrial Dynamics via the AMPK/Drp1 Pathway in APP/PS1 Mice

BACKGROUND

There are no drugs on the market that can reverse or slow Alzheimer's disease (AD) progression. A protease-resistant Cholecystokinin (CCK) analogue used in this study is based on the basic structure of CCK, which further increases the stability of the peptide fragment and prolongs its half-life in vivo. We observed a neuroprotective effect of CCK-8L in APPswe/PS1dE9 (APP/PS1) AD mice. However, its corresponding mechanisms still need to be elucidated.

OBJECTIVE

This study examined CCK-8L's neuroprotective effects in enhancing cognitive impairment by regulating mitochondrial dynamics through AMPK/Drp1 pathway in the APP/PS1 AD mice.

METHODS

Behavioural tests are applied to assess competence in cognitive functions. Transmission electron microscopy (TEM) was performed to observe the ultrastructure of mitochondria of hippocampal neurons, Immunofluorescent staining was employed to assay for Aβ1-42, APP, Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and dynamin-related protein1 (Drp1). CRISPR/Cas9 was utilized for targeted knockout of the CCKB receptor (CCKBR) in the mouse APP/PS1 hippocampal CA1 region. A model of lentiviral vector-mediated overexpression of APP in N2a cells was constructed.

RESULTS

In vivo, experiments revealed that CCK analogue and liraglutide significantly alleviated cognitive deficits in APP/PS1 mice, reduced Aβ1-42 expression, and ameliorated l damage, which is associated with CCKBR activation in the hippocampal CA1 region of mice. In vitro tests showed that CCK inhibited mitochondrial fission and promoted fusion through AMPK/Drp1 pathway.

CONCLUSIONS

CCK analogue ameliorates cognitive deficits and regulates mitochondrial dynamics by activating the CCKB receptor and the AMPK/Drp1 pathway in AD mice.

Tissue-resident alveolar macrophages reduce O3-induced inflammation via MerTK mediated efferocytosis

Lung inflammation, caused by acute exposure to ozone (O3) - one of the six criteria air pollutants - is a significant source of morbidity in susceptible individuals. Alveolar macrophages (AMØs) are the most abundant immune cells in the normal lung and their number increases following O3 exposure. However, the role of AMØs in promoting or limiting O3-induced lung inflammation has not been clearly defined. Here, we used a mouse model of acute O3 exposure, lineage tracing, genetic knockouts, and data from O3-exposed human volunteers to define the role and ontogeny of AMØs during acute O3 exposure. Lineage tracing experiments showed that 12, 24, and 72 h after exposure to O3 (2 ppm) for 3h all AMØs were tissue-resident origin. Similarly, in humans exposed to FA and O3 (200 ppb) for 135 minutes, we did not observe ~21h post-exposure an increase in monocyte-derived AMØs by flow cytometry. Highlighting a role for tissue-resident AMØs, we demonstrate that depletion of tissue-resident AMØs with clodronate-loaded liposomes led to persistence of neutrophils in the alveolar space after O3 exposure, suggesting that impaired neutrophil clearance (i.e., efferocytosis) leads to prolonged lung inflammation. Moreover, depletion of tissue-resident AMØ demonstrated reduced clearance of intratracheally instilled apoptotic Jurkat cells, consistent with reduced efferocytosis. Genetic ablation of MerTK - a key receptor involved in efferocytosis - also resulted in impaired clearance of apoptotic neutrophils followed O3 exposure. Overall, these findings underscore the pivotal role of tissue-resident AMØs in resolving O3-induced inflammation via MerTK-mediated efferocytosis.

CREB3L2 Regulates Hemidesmosome Formation during Epithelial Sealing

The long-term success rate of dental implants can be improved by establishing a favorable biological sealing with a high-quality epithelial attachment. The application of mesenchymal stem cells (MSCs) holds promise for facilitating the soft tissue integration around implants, but the molecular mechanism is still unclear and the general application of MSC sheet for soft tissue integration is also relatively unexplored. We found that gingival tissue-derived MSC (GMSC) sheet treatment significantly promoted the expression of hemidesmosome (HD)-related genes and proteins in gingival epithelial cells (GECs). The formation of HDs played a key role in strengthening peri-implant epithelium (PIE) sealing. Further, high-throughput transcriptome sequencing showed that GMSC sheet significantly upregulated the PI3K/AKT pathway, confirming that cell adhesion and HD expression in GECs were regulated by GMSC sheet. We observed that the expression of transcription factor CREB3L2 in GECs was downregulated. After treatment with PI3K pathway inhibitor LY294002, CREB3L2 messenger RNA and protein expression levels were upregulated. Further experiments showed that overexpression or knockdown of CREB3L2 could significantly inhibit or promote HD-related genes and proteins, respectively. We confirmed that CREB3L2 was a transcription factor downstream of the PI3K/AKT pathway and participated in the formation of HDs regulated by GMSC sheet. Finally, through the establishment of early implant placement model in rats, we clarified the molecular function of CREB3L2 in PIE sealing as a mechanical transmission molecule in GECs. The application of GMSC sheet-implant complex could enhance the formation of HDs at the implant-PIE interface and decrease the penetration distance of horseradish peroxidase between the implant and PIE. Meanwhile, GMSC sheet reduced the length of CREB3L2 protein expression on PIE. These findings elucidate the potential function and molecular mechanism of MSC sheet regulating the epithelial sealing around implants, providing new insights and ideas for the application of stem cell therapy in regenerative medicine.

Principal Component Analysis to Design Planning Target Volume in Oropharyngeal Cancers

PURPOSE/OBJECTIVE(S)

Standard translational shifts of the Clinical Target volume (CTV) to generate the Planning Target Volume (PTV) do not account for rotations. Head and neck positional misalignments derive in large part from rotations due to cervical spine arching and twisting in Cone Beam Computed Tomography (CBCT). Translational expansions do not track rotations, yielding coverage envelopes that unnecessarily overlap with adjacent structures. This work examines whether principal component analysis of the motion along all 6 degrees of freedom may be used to produce a more favorable PTV.

MATERIALS/METHODS

Seventy-five CBCTs of ten oropharyngeal cases were included. The records of couch shifts needed to align individual bony structures (C1-5, mandible and mastoid) between the planning image and CBCTs were recorded. A Principal Component Analysis of the shifts was used to generate an ellipsoid inflation of each CTV vertex along 6 degrees of freedom. The result was compared to a 3D ellipsoid based translational expansion, and to a described ellipsoid based vertex expansion along 6 degrees of freedom, with axes oriented in parallel to the treatment reference frame.

RESULTS

Themean (x, y) shifts in mm needed to align individually bodies C1 - C5 were respectively (-0.4, 0.5), (+.5, -0.2), (+-0.2, -0.2), (-0.2, +0.4), and (-0.5, +0.7), the monophasic pattern showing acquired curvature along both axes during treatment and demanding a PTV for coverage. A PTV was constructed using a described 6D ellipsoidal based boundary point expansion aligned along the reference frame axis or using a new theory to align against the principal components of the motion. A cyclical one-out method was used to validate the PTV models. Selected confidence intervals yielded complete coverage in >80% weeks in 80% cases. Validation testing disclosed similar complete coverage in 83-86% weekly CBCTs in the test cases with either method. The PCA 6D PTV could yield less normal structure overlap. A one out method was used to test overlap avoidance from PTVs constructed from a population of weekly CBCTs drawn from seven cases with one excluded. PTVs were drawn around target and constrictors on an extraneous case and imaged on a CT slice. Both a rolling 'ball' expansion of the vertices that applies a 3D translational ellipsoid and a PTV constructed using a 6D ellipsoid aligned against the standard reference frame overlapped with all or nearly all the constrictors in all but one trial (1/7). The 6D ellipsoid aligned against the principal motion components spared >70% of a constrictor in all trials (7/7).

CONCLUSION

PTVs remain needed to ensure target coverage in head and neck radiotherapy even with daily CT accuracy because of acquired spinal curvatures resulting in rotational displacements. A described 6D ellipsoid oriented to the reference frame can yield good coverage, but with unneeded constrictor coverage. A PCA analysis yields a PTV with equally good coverage but able to spare 70% of a constrictor.

A Bacillus subtilis Strain ZJ20 with AFB1 Detoxification Ability: A Comprehensive Analysis

As a class I carcinogen, aflatoxin can cause serious damage to various tissues and organs through oxidative stress injuries. The liver, as the target organ of AFB1, is the most seriously damaged. Biological methods are commonly used to degrade AFB1. In our study, the aflatoxin B1-degrading strain ZJ20 was screened from AFB1-contaminated feed and soil, and the degradation of AFB1 by ZJ20 was investigated. The whole genome of strain ZJ20 was analyzed, revealing the genomic complexity of strain ZJ20. The 16S rRNA analysis of strain ZJ20 showed 100% identity to Bacillus subtilis IAM 12118. Through whole gene functional annotation, it was determined that ZJ20 has high antioxidant activity and enzymatic activity; more than 100 CAZymes and 11 gene clusters are involved in the production of secondary metabolites with antimicrobial properties. In addition, B. subtilis ZJ20 was predicted to contain a cluster of genes encoding AFB1-degrading enzymes, including chitinase, laccase, lactonase, and manganese oxidase. The comprehensive analysis of B. subtilis provides a theoretical basis for the subsequent development of the biological functions of ZJ20 and the combinatorial enzyme degradation of AFB1.

Rapid construction of infectious clones for distinct Newcastle disease virus genotypes

The reverse genetics system of the Newcastle disease virus (NDV) has provided investigators with a powerful approach to understand viral molecular biology and vaccine development. It has been impressively improved with modified strategies since its first report, but it still poses some challenges. Most noteworthy, the genome complexity and length made full-length error-free cDNA assembly the most challenging and time-consuming step of NDV rescue. In the present study, we report a rapid full-length NDV genome construction with only a two-step ligation-independent cloning (LIC) strategy, which could be applied to distinct genotypes. In this approach, the genome of NDV was divided into two segments, and the cDNA clones were generated by RT-PCR followed by LIC. Subsequently, the infectious NDVs were rescued by co-transfection of the full-length cDNA clones and supporting plasmids expressing the NP, P, and L proteins of NDV in BHK-21 cells. Compared with the conventional cloning approaches, the two-step cloning method drastically reduced the number of cloning steps and saved researchers a substantial amount of time for constructing NDV infectious clones, thus enabling a rapid rescue of different genotypes of NDVs in a matter of weeks. Therefore, this two-step LIC cloning strategy may have an application to the rapid development of NDV-vectored vaccines against emerging animal diseases and the generation of different genotypes of recombinant NDVs for cancer therapy.

Chloroquine Inhibition of Autophagy Enhanced the Anticancer Effects of Listeria monocytogenes in Melanoma

Listeria monocytogenes has been shown to exhibit antitumor effects. However, the mechanism remains unclear. Autophagy is a cellular catabolic process that mediates the degradation of unfolded proteins and damaged organelles in the cytosol, which is a double-edged sword in tumorigenesis and treatment outcome. Tumor cells display lower levels of basal autophagic activity than normal cells. This study examined the role and molecular mechanism of autophagy in the antitumor effects induced by LM, as well as the combined antitumor effect of LM and the autophagy inhibitor chloroquine (CQ). We investigated LM-induced autophagy in B16F10 melanoma cells by real-time PCR, immunofluorescence, Western blotting, and transmission electron microscopy and found that autophagic markers were increased following the infection of tumor cells with LM. The autophagy pathway in B16F10 cells was blocked with the pharmacological autophagy inhibitor chloroquine, which led to a significant increase in intracellular bacterial multiplication in tumor cells. The combination of CQ and LM enhanced LM-mediated cancer cell death and apoptosis compared with LM infection alone. Furthermore, the combination of LM and CQ significantly inhibited tumor growth and prolonged the survival time of mice in vivo, which was associated with the increased colonization and accumulation of LM and induced more cell apoptosis in primary tumors. The data indicated that the inhibition of autophagy by CQ enhanced LM-mediated antitumor activity in vitro and in vivo and provided a novel strategy to improving the anticancer efficacy of bacterial treatment.

Probiotic Properties of Chicken-Derived Highly Adherent Lactic Acid Bacteria and Inhibition of Enteropathogenic Bacteria in Caco-2 Cells

Lactic acid bacteria (LAB) as probiotic candidates have various beneficial functions, such as regulating gut microbiota, inhibiting intestinal pathogens, and improving gut immunity. The colonization of the intestine is a prerequisite for probiotic function. Therefore, it is necessary to screen the highly adherent LAB. In this study, the cell surface properties, such as hydrophobicity, auto-aggregation, co-aggregation, and adhesion abilities of the six chicken-derived LAB to Caco-2 cells were investigated. All six strains showed different hydrophobicity (21.18-95.27%), auto-aggregation (13.61-30.17%), co-aggregation with Escherichia coli ATCC 25922 (10.23-36.23%), and Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311 (11.71-39.35%), and adhesion to Caco-2 cells (8.57-26.37%). Pediococcus pentosaceus 2-5 and Lactobacillus reuteri L-3 were identified as the strains with strong adhesion abilities (26.37% and 21.57%, respectively). Moreover, these strains could survive in a gastric acid environment at pH 2, 3, and 4 for 3 h and in a bile salt environment at 0.1%, 0.2%, and 0.3% (w/v) concentration for 6 h. Furthermore, the cell-free supernatant of P. pentosaceus 2-5 and L. reuteri L-3 inhibited the growth of enteropathogenic bacteria and the strains inhibited the adhesion of these pathogens to Caco-2 cells. In this study, these results suggested that P. pentosaceus 2-5 and L. reuteri L-3, isolated from chicken intestines might be good probiotic candidates to be used as feed additives or delivery vehicles of biologically active substances.

5'-Nucleotidase is dispensable for the growth of Salmonella Typhimurium but inhibits the bactericidal activity of macrophage extracellular traps

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a zoonotic pathogen that causes severe gastroenteritis. The 5'-nucleotidases of pathogens can dephosphorylate adenosine phosphates, boost adenosine levels and suppress the pro-inflammatory immune response. In our previous study, an extracellular nuclease, 5'-nucleotidase, was identified in the extracellular proteins of S. Typhimurium. However, the nuclease activity and the function of the 5'-nucleotidase of S. Typhimurium have not been explored. In the present study, deletion of the 5'-nucleotidase gene is dispensable for S. Typhimurium growth, even under environmental stress. Fluorescence microscopy revealed that the 5'-nucleotidase mutant induced more macrophage extracellular traps (METs) than the wild type did. Furthermore, recombinant 5'-nucleotidase protein (r5Nuc) could degrade λDNA, and the nuclease activity of r5Nuc was optimum at 37 °C and pH 6.0-7.0. The Mg²⁺ enhanced the nuclease activity of r5Nuc, whereas Zn²⁺ inhibited it. Meanwhile, deletion of the 5'-nucleotidase gene increased the bactericidal activity of METs, and r5Nuc could degrade METs and inhibit the bactericidal activity of METs. In conclusion, S. Typhimurium growth was independent of 5'-nucleotidase, but the nuclease activity of 5'-nucleotidase assisted S. Typhimurium to evade macrophage-mediated extracellular killing through degrading METs.

Rescue of an enterotropic Newcastle disease virus strain ZM10 from cloned cDNA and stable expressing an inserted foreign gene

BACKGROUND

Newcastle disease virus (NDV) strain ZM10, a typical enterotropic avirulent vaccine strain, has been widely used in China for chickens against Newcastle disease. To elucidate its enterotropic mechanism and develop recombiant multivalent vaccines based on it, the reverse genetics system for NDV ZM10 is an indispensable platform.

RESULTS

A full-length cDNA clone of NDV ZM10 and three supporting plasmids were constructed using the ligation-independent cloning method. Recombinant NDV rZM10 was successfully rescued after these plasmids were co-transfected into BHK-21 cells. Besides, the recombinant virus rZM10-RFP encoding the red fluorescent protein was generated by inserting the RFP gene into the full-length clone of NDV between the P and M genes. These rescued viruses were genetically and biologically identical to the parental strain and showed similar growth kinetics.

CONCLUSION

The recovery system of NDV ZM10 strain was established, and can be used as a foundation for research on the enterotropic mechanism and development of multivalent vaccines against viral diseases of livestock and poultry.

Prediction of nitrogen excretion from data on dairy cows fed a wide range of diets compiled in an intercontinental database: A meta-analysis

Manure nitrogen (N) from cattle contributes to nitrous oxide and ammonia emissions and nitrate leaching. Measurement of manure N outputs on dairy farms is laborious, expensive, and impractical at large scales; therefore, models are needed to predict N excreted in urine and feces. Building robust prediction models requires extensive data from animals under different management systems worldwide. Thus, the study objectives were (1) to collate an international database of N excretion in feces and urine based on individual lactating dairy cow data from different continents; (2) to determine the suitability of key variables for predicting fecal, urinary, and total manure N excretion; and (3) to develop robust and reliable N excretion prediction models based on individual data from lactating dairy cows consuming various diets. A raw data set was created based on 5,483 individual cow observations, with 5,420 fecal N excretion and 3,621 urine N excretion measurements collected from 162 in vivo experiments conducted by 22 research institutes mostly located in Europe (n = 14) and North America (n = 5). A sequential approach was taken in developing models with increasing complexity by incrementally adding variables that had a significant individual effect on fecal, urinary, or total manure N excretion. Nitrogen excretion was predicted by fitting linear mixed models including experiment as a random effect. Simple models requiring dry matter intake (DMI) or N intake performed better for predicting fecal N excretion than simple models using diet nutrient composition or milk performance parameters. Simple models based on N intake performed better for urinary and total manure N excretion than those based on DMI, but simple models using milk urea N (MUN) and N intake performed even better for urinary N excretion. The full model predicting fecal N excretion had similar performance to simple models based on DMI but included several independent variables (DMI, diet crude protein content, diet neutral detergent fiber content, milk protein), depending on the location, and had root mean square prediction errors as a fraction of the observed mean values of 19.1% for intercontinental, 19.8% for European, and 17.7% for North American data sets. Complex total manure N excretion models based on N intake and MUN led to prediction errors of about 13.0% to 14.0%, which were comparable to models based on N intake alone. Intercepts and slopes of variables in optimal prediction equations developed on intercontinental, European, and North American bases differed from each other, and therefore region-specific models are preferred to predict N excretion. In conclusion, region-specific models that include information on DMI or N intake and MUN are required for good prediction of fecal, urinary, and total manure N excretion. In absence of intake data, region-specific complex equations using easily and routinely measured variables to predict fecal, urinary, or total manure N excretion may be used, but these equations have lower performance than equations based on intake.

Ectopic expression of BrIQD35 promotes drought stress tolerance in Nicotiana benthamiana

The plant IQD gene family is responsive to a variety of stresses. In this study, we studied the structural features and functions of the gene BrIQD35 in Chinese cabbage, a member of the IQD gene family. BrIQD35 was cloned and shown to contain an IQ motif. Transient expression of BrIQD35 indicated that it was localized on the plasma membrane and was significantly upregulated under drought and salt stress in Chinese cabbage. To further identify the function of BrIQD35, it was heterologously overexpressed in Nicotiana benthamiana. Although there was no significant difference between BrIQD35-overexpressed and wild-type (WT) plants under salt stress, WT N. benthamiana showed more wilting than the BrIQD35-overexpressed plants under drought stress. Since the IQ motif has been annotated as a CaM binding site, yeast two-hybrid assays were used to explore the interaction between BrIQD35 and CaM. The results indicated that BrIQD35 interacts weakly with CaMb, but not with CaMa, suggesting that BrIQD35 may function through the Ca2+ -CaMb pathway. The findings reveal a novel gene involved in drought tolerance, which is important for plant breeding and quality improvement for Chinese cabbage.

Susceptibility-weighted imaging cannot distinguish radionecrosis from recurrence in brain metastases after radiotherapy: a comparison with high-grade gliomas

AIM

To explore the efficiency of susceptibility-weighted imaging (SWI) in the differential diagnosis of recurrence from radionecrosis in brain metastases (BM) and in high-grade gliomas (HGG).

MATERIALS AND METHODS

From September 2016 to November 2018, 56 patients with BM and 42 patients with HGG were included in this retrospective study. BM and HGG were assigned to the recurrence and radionecrosis groups according to their histopathology or follow-up results. The proportion of dark signal intensity (proDSI), which was defined as the area of dark signal on SWI or the enhancing area on contrast-enhanced T1-weighted imaging (T1WI), was calculated for each patient. Analysis of variance (ANOVA) with Tukey's honestly significant difference test was used for the repeat multiple comparisons. Receiver operating characteristic curve analysis was performed to validate the diagnostic performance.

RESULTS

For HGG, the proDSI in the recurrence group was significantly lower than that in the radionecrosis group (0.13 ± 0.05 versus 0.43 ± 0.11, p<0.001); however, for BM, no statistical difference was found between groups (0.49 ± 0.09 versus 0.46 ± 0.08, p=0.26). proDSI had the best diagnostic performance (AUC = 0.87, 95% CI: 0.76-0.98; sensitivity = 0.87; specificity = 0.88) for HGG, when a cut-off value of 0.21 was selected.

CONCLUSIONS

Semi-quantitative analysis using SWI is feasible for the differential diagnosis between recurrence and radionecrosis in HGG, but is not feasible in BM. Semi-quantitative assessment based on SWI should interpreted with caution in BM after radiotherapy in clinical practice.

[Analysis of 2 diagnostic criteria of echocardiography for coronary artery aneurysm in Kawasaki disease]

Objective: To analyze the difference between Z score and previous criteria in the diagnosis characteristics of coronary artery aneurysm (CAA) in Kawasaki disease, and to investigate the clinical distribution of Kawasaki disease CAA in the Z score group. Methods: This study retrospectively analyzed the clinical and echocardiographic data of 2 419 children with Kawasaki disease in Shenzhen Children's Hospital from January 2009 to December 2019. The traditional criteria and Z score criteria were used to diagnose CAA, and the differences of diagnostic efficiency between the 2 diagnostic methods were analyzed. The clinical distribution characteristics of CAA in children with Kawasaki disease were analyzed by grouping their sex, clinical classification (complete Kawasaki disease, incomplete Kawasaki disease) the sensitivity to intravenous immunoglobulin (IVIG) (IVIG-sensitive Kawasaki disease,IVIG-unresponsive Kawasaki disease). And the course of the disease (≤6 weeks, >6-8 weeks, >8 weeks to 6 months) etc. The χ² test or Kruskal-Wallis test was used for comparison between the groups, and the Kappa test was used for consistency evaluation. Results: Among the 2 419 children with Kawasaki disease, 1 558 were males and 861 were females. The age of onset was 1.8 (1.0, 3.2) years. The rate of CAA by Z score criteria was higher than that by traditional method (21.9% (529/2 419) vs. 13.9% (336/2 419), χ²=1 074.94, P<0.001). Compared to the traditional method, the Z score criteria found higher rate of CAA in male patients, patients with incomplete Kawasaki disease, and IVIG-unresponsive patients (25.2% (392/1 558) vs. 16.0% (249/1 558), (32.7% (166/507) vs. 19.5% (99/507), 30.5% (95/312) vs. 24.0% (75/312), χ²=694.05, 216.19, 184.37, all P<0.001). The Z score criteria was consistent with the traditional method in diagnosing CAA (κ=0.642,P<0.001). Moreover, in the Z score criteria, the rate of CAA in males (25.2%, 392/1 558) was higher than that in females (15.9%, 137/861), higher in incomplete Kawasaki cases (32.7%, 166/507) than that in complete Kawasaki case (19.0%, 363/1 912), and higher in IVIG-unresponsive cases (30.4%, 95/312) than that in IVIG-sensitive cases (20.6%, 434/2 107), with statistically significant differences (χ²=27.76, 44.38, 15.43, all P<0.001). Coronary Z score of course ≤ 6 weeks was greater than that of course between>6-8 weeks and >8 weeks to 6 months (1.3 (0.7, 2.3) vs. 0.7 (0.3, 1.4), 0.7 (0.3, 1.3), Z=20.65, 13.70, both P<0.001). Conclusions: The rate of CAA in Kawasaki disease by Z score criteria is higher than that by traditional method. In the Z score group, most CAA occur within 6 weeks of the course of the disease, and the rate of CAA in male, incomplete Kawasaki disease, and IVIG-unresponsive is higher.

[Research advances on application of botulinum toxin type A in scar prevention and treatment]

The wound healing time, tension of wound edge, proliferation of fibroblast, and extracellular matrix deposition are the important factors of scar formation, and botulinum toxin type A can regulate the above. Prevention and treatment of scar with botulinum toxin type A is one of the hot topics of clinical research in recent years. This paper briefly reviews researches by scholars at home and abroad on the mechanism, clinical application, complications, and adverse effects of botulinum toxin type A in scar prevention and treatment.

[Evaluation of the perioperative period and long-term outcomes of minimally invasive LTE and minimally invasive CTLE esophagectomy for stage Ⅰ-Ⅲ cervical esophageal carcinoma based on propensity score matching analysis]

Objective: To evaluate the perioperative period and long-term effects of minimally invasive gasless laparoscopic transhiatal esophagectomy (LTE) and minimally invasive combined thoracoscopic and laparoscopic esophagectomy (CTLE) for stageⅠ-Ⅲ cervical esophageal cancer. Methods: The clinical data of 158 consecutive patients with cervical esophageal cancer stageⅠto Ⅲ who underwent minimally invasive CTLE or LTE esophagectomy in the Department of Thoracic Surgery, Beijing Tongren Hospital from January 2008 to December 2019 were retrospectively analyzed. A total of 40 pairs of cases were matched (40 cases of CTLE and 40 cases of LTE surgery) after using the propensity score matching analysis which aimed to balance the influence of confounding factors between groups, including 43 males and 37 females, aged 51 to 81 (62.5±7.0) years old. The perioperative variables and long-term outcomes of the two groups were compared. Results: The operation time ((148.0±31.3) min vs (201.3±48.3) min), intraoperative blood loss ((192.6±77.9) ml vs (387.8±112.4) ml), ICU monitoring time (0 day vs 1 day), and the complication rates of postoperative pneumonia (0 vs 15%) and arrhythmia (2.5% vs 20%) were lower in the LTE group than that of in the CTLE group(all P<0.05). The number of lymph node dissections in the CTLE group was higher than that of in the LTE group (21.2±6.1 vs 12.9±4.3, P<0.001). The 3-and 5-year overall survival (OS) rate and disease-free survival (DFS) rate in the LTE group (OS: 53.53% and 34.27%, DFS: 43.62% and 24.89%, respectively) and the CTLE group (OS: 59.48% and 37.29%, DFS: 49.12% and 28.82%, respectively) had no statistical differences (all P>0.05). Conclusion: The LTE group has advantages in reducing operation time, intraoperative bleeding, ICU monitoring time, postoperative incidence of pneumonia and arrhythmia, and its long-term prognosis is comparable to that of the CTLE group.

TREATMENT OF SECONDARY LOWER LIMB LYMPHEDEMA AFTER GYNECOLOGIC CANCER WITH COMPLEX DECONGESTIVE THERAPY

Secondary lower extremity lymphedema is a common complication of treatment for gynecological cancers. Conservative therapy plays an important role in the treatment of patients with secondary lower extremity lymphedema; in particular, complex decongestive therapy (CDT) has been recognized as an effective nonoperative technique for these patients. But CDT therapy for secondary lower extremity lymphedema remains a problem in China because this technique and its effectiveness have not achieved widespread use and popularity. Our goal was to assess effects of CDT in patients with secondary lower limb lymphedema after treatment for gynecological cancers. The retrospective study consisted of 60 patients who were treated with 20 sessions of CDT. Assessments included objective changes in limb circumference, degree of LE, imaging features, and incidence of erysipelas before and after CDT treatment. We found that CDT can effectively improve lymph stasis and promote backflow, and decrease circumference, interstitial fluid content, and incidence of erysipelas of lymphedematous lower limb. Our results demonstrate that CDT is an effective treatment method for patients with secondary lower limb lymphedema following treatment for gynecologic cancers. This technique should be more widely utilized and popularized in China to improve the quality of life of millions of patients with secondary lower limb lymphedema.

A high precision phase measurement system implemented in FPGA with phase interpolator

High precision timing distribution is crucial to many large scale cosmology and particle physics experiments. Besides the space and energy information, the accurate timing provides an extra dimension for physics event reconstruction. In the timing distribution system, accurate clock phase measurement is an indispensable tool to monitor the phase drift and to achieve accurate phase adjustment. This paper introduces a novel phase measurement method implemented in the Xilinx Field Programmable Gate Array (FPGA). It uses the dedicated phase interpolator in the multi-gigabit transceiver. A design based on this method is implemented within the Kintex Ultrascale series FPGA. The preliminary test result shows that a sub-picosecond level precision is achieved. With this system, the nonlinearity of the phase adjustment in the Xilinx transceiver is measured.

[Association between serum uric acid to creatinine ratio and metabolic syndrome based on community residents in Chashan town, Dongguan city]

Objective: To analyze the association between serum uric acid to creatinine ratio (SUA/Cr) and metabolic syndrome among community residents in Chashan town, Dongguan city. Methods: Participants were from the prospective cohort study of chronic diseases in natural populations in South China conducted in Chashan town, Dongguan city from 2018 to 2019. A total of 11 334 participants with complete data were included by using convenient sampling method. Demographic characteristics, lifestyle and health status were collected through questionnaire and physical examination. The venous blood of the subjects was collected to detect the levels of serum uric acid, creatinine and blood lipid. All participants were divided into four groups (Q1-Q4) according to the quartile of SUA/Cr level. The relationship between SUA/Cr and metabolic syndrome and its components (abdominal obesity, high triglyceride, low level of high density lipoprotein cholesterol, hypertension and abnormal glucose metabolism) were analyzed by using logistic regression model. Results: The mean age of 11 334 participants was (49.52±10.02) years. Male participants accounted for 44.2% (5 015/11 334). The prevalence of metabolic syndrome was 31.2% (3 532/11 334), and the level of SUA/Cr was 5.17±1.53. The prevalence of metabolic syndrome in group Q1-Q4 was 22.3% (631/2 834), 26.5% (752/2 833), 34.9% (988/2 833) and 41.0% (1 161/2 834), respectively. After adjusting for relevant confounding factors, the result of logistic regression model showed that compared with group Q1, the risk of metabolic syndrome in group Q2-Q4 was significantly higher, with OR (95%CI) values about 1.41 (1.23-1.60), 2.19 (1.93-2.49) and 3.01 (2.65-3.42) respectively. The risk of each component of metabolic syndrome in group Q2-Q4 was higher (P_trend<0.001). The SUA/Cr level of participants with normal uric acid level was significantly positively correlated with metabolic syndrome. The risk of metabolic syndrome increased with the increase of SUA/Cr level, but there was the same trend without significant differences in patients with hyperuricemia (P_interaction=0.008). Conclusion: There is a positive correlation between SUA/Cr level and the risk of metabolic syndrome among community residents in Chashan town, Dongguan city.

Nuclear Receptor 4A2 (NR4A2/NURR1) Regulates Autophagy and Chemoresistance in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with poor prognosis and chemotherapy with gemcitabine has limited effects and is associated with development of drug resistance. Treatment of Panc1 and MiaPaca2 pancreatic cancer cells with gemcitabine induced expression of the orphan nuclear receptor 4A2 (NURR1) and analysis of the cancer genome atlas indicated the NURR1 is overexpressed in pancreatic tumors and is a negative prognostic factor for patient survival. Results of NURR1 knockdown or treatment with the NURR1 antagonist 1,1-bis(3΄-indolyl)-1-(p-chlorophenyl)methane (C-DIM 12) demonstrated that NURR1 was pro-oncogenic in pancreatic cancer cells and regulated cancer cell and tumor growth and survival. NURR1 is induced by gemcitabine and serves as a key drug-resistance factor and is also required for gemcitabine-induced cytoprotective autophagy. NURR1 regulated genes were determined by RNA sequencing of mRNAs expressed in MiaPaCa2 cells expressing NURR1 and in CRISPR/Cas9 gene edited cells for NURR1 knockdown and KEGG enrichment analysis of the differentially expressed genes showed that autophagy was the major pathway regulated by NURR1. Moreover, NURR1 regulated expression of two major autophagic genes ATG7 and ATG12 which are also overexpressed in pancreatic tumors and like NURR1 are negative prognostic factors for patient survival. Thus, gemcitabine-induced cytoprotective autophagy is due to the NURR1 - ATG7/ATG12 axis and this can be targeted and disrupted by NURR1 antagonist C-DIM12 demonstrating the potential clinical applications for combination therapies with gemcitabine and NURR1 antagonists.

[Application effects of free transplantation of autologous omentum in treating maxillofacial infection complicated with complex sinus tract]

Objective: To investigate the application effects of free transplantation of autologous omentum in treating maxillofacial infection complicated with complex sinus tract. Methods: The retrospective observational study method was used. Four patients with maxillofacial infection complicated with complex sinus tract were admitted to Department of Burns and Plastic Surgery of the Second Affiliated Hospital of Air Force Medical University from July 2017 to the December 2019, including 3 males and 1 female aged 36-60 years. Preoperative facial computed tomography (CT) was performed on patients for calculating the volume of sinus tract. During the operation, the sinus tract was thoroughly debrided, and the volume of the tissue defect was about 5 cm×3 cm×2 cm-10 cm×5 cm×3 cm after debridement. The tissue defect area was filled with omentum of 100-300 mL which was cut under laparoscopy. The artery and vein on the right side of the omentum were reserved as the vascular pedicle of the donor area, which were anastomosed with the facial artery and external jugular vein of the recipient area. The survival of omentum, and the occurrences of reinfection and complication were observed after operation, respectively. On the 10th day and in 1 month after the operation, the blood supply of omentum was examined by colored Doppler ultrasound and CT angiography, and the filling of tissue defect area was examined by head and face CT. During follow-up after the operation, the recoveries of face appearance and function and scar hyperplasia in the donor area. Results: The transplanted omentums in 4 patients survived after the operation with no reinfection and complication. On the 10th day and in 1 month after the operation, the transplanted omentums had good blood supply, and the filled area with omentum was in good shape, without formation of dead cavity. During follow-up of 6-10 months after surgery, the appearance and function of face recovered well, and there was no obvious scar hyperplasia in the donor area. Conclusions: After free transplantation of omentum in treating maxillofacial infection with complex sinus tract, the patients have good facial appearance and function, and the application of laparoscopy results in little damage to the patients and quick postoperative recovery.

[Explorative study of the immobilizing effect of full-thickness skin subcutaneous grafting on allogeneic full-thickness skin graft in rats]

Objective: To investigate the immobilizing effect of full-thickness skin subcutaneous grafting on allogeneic full-thickness skin graft in rats. Methods: The experimental research method was used. The inbred male Brown-Norway rats (n=10) and Lewis rats (n=10) were used as donors and recipients respectively. After subcutaneously full-thickness separation of a 2.2 cm×2.2 cm area on the nape of the recipient rat, a full-thickness skin of 2.0 cm×2.0 cm taken from the abdomen of the donor rat was subcutaneously grafted, and the donor site was pulled together and sutured. The autologous skin over the allograft in the recipient rat was excised 5-6 d after grafting, and the stitches were removed 7 d after excision. Within 2 months after grafting, the feeding, activity, and survival of the donor and recipient rats, behavior of tearing and scratching the wounds of the recipient rats, the wound condition after autologous skin excision in recipient rats, and the survival and hair growth of the grafted allogeneic skin were observed. Results: Within 2 months after grafting, the donor and recipient rats all ate normally and could move freely with no abnormal death. No tearing or scratching of the wounds occurred in recipient rats. There was a small amount of exudation and partial epidermal desquamation after autologous skin excision in recipient rats. All transplanted allografts survived, which were free of infection and necrosis, with new hairs growing out smoothly. Conclusions: The immobilizing method of full-thickness skin subcutaneous grafting of allogeneic full-thickness skin graft in rats is simple and time-saving without postoperative dressing change, with reliable pressure fixation and high survival rate of skin grafts, which can be promoted for animal skin grafting models.

[Establishment and validation of a clinical prediction model for infection risk at the placement sites of skin and soft tissue expanders]

Objective: To establish a clinical prediction model for infection risk at the placement sites of skin and soft tissue expanders (hereinafter termed as expanders) and to validate the predictive value of the model. Methods: A retrospective observational study was conducted. Totally 2 934 patients who underwent skin and soft tissue dilatation surgery in the Department of Plastic Surgery of the First Affiliated Hospital of Air Force Medical University from January 2009 to December 2018 and met the selection criteria were included. There were 1 867 males and 1 067 females, with a median age of 18 years. Totally 3 053 skin and soft tissue expansion procedures were performed with 4 266 expanders implanted. The following indexes were selected as predictor variables, including patients' age, gender, marital status, ethnicity, hospital admission, surgical indication, disease duration, with/without history of smoking, history of drinking, history of blood transfusion, history of underlying diseases, and inability to use cephalosporin antibiotics due to allergy, number of expander in a single placement, rated volume of expander, water injection rate of expander in the first time, placement site of expander, anesthesia method, duration of operation, and with/without postoperative hematoma evacuation, and infection at the placement site of expander as the outcome variable. Univariate analysis of the data was performed using least absolute shrinkage and selection operator (LASSO) regression to screen the potential risk factors affecting infection at the placement sites of expanders, the factors selected by the univariate analysis were subjected to binary multivariate logistic regression analysis to screen the independent risk factors affecting infection at the placement sites of expanders, and a nomogram prediction model for the occurrence of infection at the placement sites of expanders was established. The C index and Hosmer-Lemeshow goodness of fit test were used to evaluate the discrimination and accuracy of the model, respectively, and the bootstrap resampling was used for internal verification. Results: The results of LASSO regression showed that age, gender, hospital admission, surgical indication, disease duration, history of drinking, history of heart disease, history of viral hepatitis, history of hypertension, inability to use cephalosporin antibiotics due to allergy, number of expander in a single placement, rated volume of expander, placement site of expander, postoperative hematoma evacuation were the potential risk factors for infection at the placement sites of expanders (regression coefficient=-0.005, 0.170, 0.999, 0.054, 0.510, -0.003, 0.395, -0.218, 0.029, 0.848, -0.116, 0.175, 0.085, 0.202). Binary multivariate logistic regression analysis showed that male, emergency admission, disease duration ≤1 year, inability to use cephalosporin antibiotics due to allergy, rated volumes of expanders ≥200 mL and <400 mL or ≥400 mL, and expanders placed in the trunk or the limbs were the independent risks factors for infection at the placement sites of expanders (odds ratio=1.37, 3.21, 2.00, 2.47, 1.70, 1.73, 1.67, 2.16, 95% confidence interval=1.04-1.82, 1.09-8.34, 1.38-2.86, 1.29-4.41, 1.07-2.73, 1.02-2.94, 1.09-2.58, 1.07-4.10, P<0.05 or P<0.01). The C index for evaluating the discriminative degree of the model was 0.63, the Hosmer-Lemeshow goodness of fit test for evaluating the accuracy of the model showed P=0.685, and the C index for internal validation by the bootstrap resampling was 0.60. Conclusions: Male, emergency admission, disease duration ≤1 year, inability to use cephalosporin antibiotics due to allergy, rated volume of expander ≥200 mL, and expanders placed in the trunk or the limbs are the independent risk factors for infection at the placement sites of expanders. The clinical prediction model for infection risk at the placement sites of expanders was successfully established based on these factors and showed a certain predictive effect.

Mutations of the c-Kit and PDGFRA gene in gastrointestinal stromal tumors among hakka population of Southern China

Aims

The aim of the present study was to investigate mutation status of the cKit and PDGFRA genes in patients with a gastrointestinal stromal tumor (GIST).

Methods

In total, 96 patients with a GIST were included in the study, in which polymerase chain reaction amplification and gene sequencing were used to detect the sequences of exons 9, 11, 12, 13, 14, 17, and 18 in KIT and exons 12, 14, and 18 in PDGFRA.

Results

KIT mutations were detected in 65 cases (67.71%), of which 81.54% (53/65) were located on exon 11, 12.31% (8/65) were located on exon 9, 4.61% (3/65) were located on exon 17, which included a concomitant mutation of exon 9 and 11, and 4.08% (2/65) were located on exon 13, which included a concomitant mutation on exon 11. The most common mutation in exon 11 was deletion, which accounted for 77.36% (41/53) of the cases, followed by a point mutation observed in 22.64% (12/53) of the cases. Among the 31 GIST cases without a KIT mutation, a mutation in PDGFRA was detected in 5 cases (5.21%, 5/96; 16.13%, 5/31). With respect to gender, age, tumor max diameter, tumor position, and mitotic index, there were no significant differences between KIT/PDGFRA mutations and non-mutations.

Conclusions

GIST mainly occurs in the stomach, and the cytological morphology is mainly spindle cells, and the mutations mainly occur in KIT genes. We need a large sample size to analyze the regularity of GIST gene mutations in Hakka population and understand the independent prognostic correlation of all KIT/PDGFRA genotypes.