Clinical development of MRI-based multi-sequence multi-regional radiomics model to predict lymph node metastasis in rectal cancer

OBJECTIVE

We aim to construct a magnetic resonance imaging (MRI)-based multi-sequence multi-regional radiomics model that will improve the preoperative prediction ability of lymph node metastasis (LNM) in T3 rectal cancer.

METHODS

Multi-sequence MRI data from 190 patients with T3 rectal cancer were retrospectively analyzed, with 94 patients in the LNM group and 96 patients in the non-LNM group. The clinical factors, subjective imaging features, and the radiomic features of tumor and peritumoral mesorectum region of patients were extracted from T2WI and ADC images. Spearman's rank correlation coefficient, Mann-Whitney's U test, and the least absolute shrinkage and selection operator were used for feature selection and dimensionality reduction. Logistic regression was used to construct six models. The predictive performance of each model was evaluated by the receiver operating characteristic curve (ROC). The differences of each model were characterized by area under the curve (AUC) via the DeLong test.

RESULTS

The AUCs of T2WI, ADC single-sequence radiomics model and multi-sequence radiomics model were 0.73, 0.75, and 0.78, respectively. The multi-sequence multi-regional radiomics model with improved performance was created by combining the radiomics characteristics of the peritumoral mesorectum region with the multi-sequence radiomics model (AUC, 0.87; p < 0.01). The AUC of the clinical model was 0.68, and the MRI-clinical composite evaluation model was obtained by incorporating the clinical data with the multi-sequence multi-regional radiomics features, with an AUC of 0.89.

CONCLUSION

The MRI-based multi-sequence multi-regional radiomics model significantly improved the prediction ability of LNM for T3 rectal cancer and could be applied to guide surgical decision-making in patients with T3 rectal cancer.

[Respiratory virus infection and its influence on outcome in children with septic shock]

Objective: To investigate respiratory virus infection in children with septic shock in pediatric care units (PICU) in China and its influence on clinical outcomes. Methods: The clinical data of children with septic shock in children's PICU from January 2018 to December 2019 in 10 Chinese hospitals were retrospectively collected. They were divided into the pre-COVID-19 and post-COVID-19 groups according to the onset of disease, and the characteristics and composition of respiratory virus in the 2 groups were compared. Matching age, malignant underlying diseases, bacteria, fungi and other viruses, a new database was generated using 1∶1 propensity score matching method. The children were divided into the respiratory virus group and non-respiratory virus group according to the presence or absence of respiratory virus infection; their clinical characteristics, diagnosis, and treatment were compared by t-test, rank sum test and Chi-square test. The correlation between respiratory virus infection and the clinical outcomes was analyzed by logistic regression. Results: A total of 1 247 children with septic shock were included in the study, of them 748 were male; the age was 37 (11, 105) months. In the pre-and post-COVID-19 groups, there were 530 and 717 cases of septic shock, respectively; the positive rate of respiratory virus was 14.9% (79 cases) and 9.8% (70 cases); the seasonal distribution of septic shock was 28.9% (153/530) and 25.9% (185/717) in autumn, and 30.3% (161/530) and 28.3% (203/717) in winter, respectively, and the corresponding positive rates of respiratory viruses were 19.6% (30/153) and 15.7% (29/185) in autumn, and 21.1% (34/161) and 15.3% (31/203) in winter, respectively. The positive rates of influenza virus and adenovirus in the post-COVID-19 group were lower than those in the pre-COVID-19 group (2.1% (15/717) vs. 7.5% (40/530), and 0.7% (5/717) vs. 3.2% (17/530), χ2=21.51 and 11.08, respectively; all P<0.05). Rhinovirus virus were higher than those in the pre-Covid-19 group (1.7% (12/717) vs. 0.2% (1/530), χ2=6.51, P=0.011). After propensity score matching, there were 147 cases in both the respiratory virus group and the non-respiratory virus group. Rate of respiratory failure, acute respiratory distress, rate of disseminated coagulation dysfunction, and immunoglobulin usage of the respiratory virus group were higher than those of non-respiratory virus group (77.6% (114/147) vs. 59.2% (87/147), 17.7% (26/147) vs. 4.1% (6/147), 15.6% (25/147) vs. 4.1% (7/147), and 35.4% (52/147) vs. 21.4% (32/147); χ2=11.07, 14.02, 11.06 and 6.67, all P<0.05); and PICU hospitalization of the former was longer than that of the later (7 (3, 16) vs. 3 (1, 7)d, Z=5.01, P<0.001). Univariate logistic regression analysis showed that the presence of respiratory viral infection was associated with respiratory failure, disseminated coagulation dysfunction, the use of mechanical ventilation, and the use of immunoglobulin and anti-respiratory viral drugs (OR=2.42, 0.22, 0.25, 0.56 and 1.12, all P<0.05). Conclusions: The composition of respiratory virus infection in children with septic shock is different between pre and post-COVID-19. Respiratory viral infection is associated with organ dysfunction in children with septic shock. Decreasing respiratory viral infection through respiratory protection may improve the clinical outcome of these children.

Cost-effectiveness analysis of nivolumab versus placebo for relapsed malignant mesothelioma

BACKGROUND

Although nivolumab has shown clinical benefits for relapsed malignant mesothelioma, its cost-effectiveness requires further investigation.

AIM

This study aimed to evaluate the cost-effectiveness of nivolumab compared to placebo for relapsed malignant mesotheliomas from the perspective of the Chinese healthcare system.

METHOD

A three-state Markov model was developed based on data from the phase 3 randomized CONFIRM clinical trial. The drug cost and utility values for the health state were obtained from the relevant literature. The measured outcomes included quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratio (ICER). Probabilistic and one-way sensitivity analyses (OWSA) were performed to assess the uncertainty of the model.

RESULTS

Patients receiving nivolumab gained more health benefits (0.65 QALYs vs. 0.43 QALYs). The cost was higher ($25,806.08 vs. $9,310.74) than for patients in the placebo group, resulting in an ICER of $75,805.11/QALY, which was above the willingness-to-pay (WTP) threshold of three times per capita GDP ($35,864.61) in China. The result of OWSA indicated that the cost of nivolumab, the utility of the disease progression, and the discount rate were the most significant factors. Probabilistic sensitivity analysis suggested that the probability that nivolumab was not cost-effective as was 100.00% above the specified WTP threshold.

CONCLUSION

From the perspective of the Chinese healthcare system, nivolumab was not as cost-effective as placebo for relapsed malignant mesothelioma.

A case of KAT6A syndrome with a newly discovered mutation in the KAT6A gene, mainly manifested as bone marrow failure syndrome

Objective: The clinical and genetic characteristics of a child with inherited bone marrow failure syndrome as prominent clinical manifestations and special facial features were analyzed, and the etiology and mechanism were explored in, combination with clinical practice. Methods: Blood samples and clinical information were collected separately from the proband and their biological parents. The pathogenic variant was verified using next-generation sequencing technology screening, and the candidate variable sites were confirmed by using Sanger sequencing among all members of the family. Results: A heterozygous nonsense mutation in exon 17 of KAT6A (NM_006766), c.4177G > T (p.E1393*) predicted to cause truncation within the acidic domain of the protein was identified. Pedigree analysis did not reveal any variation in this locus between the proband's father and mother. No report of this pathogenic variant was found in a literature search of domestic and foreign databases, indicating that it is a newly discovered mutation. According to the guidelines of the American College of Medical Genetics, the variation was preliminarily determined to be a pathogenic. The newly discovered heterozygous mutation in KAT6A may be the cause of the disease in this child. Additionally, inherited bone marrow failure syndrome is a prominent manifestation. Conclusion: This study not only provides us with an in-depth understanding of this rare syndrome but also deepens our understanding of the function of KAT6A.

Case report: Amplatzer septal occluder device migration into the descending thoracic aortic isthmus: percutaneous retrieval and redeployment

Percutaneous closure has emerged as the standard treatment for secundum-type atrial septal defects (ASDs). However, there is a rare but serious complication of occluder device migration and embolization to the heart chambers or distal vasculature during or shortly after implantation. Although this occurrence is extremely rare, it can have disastrous consequences. Fortunately, advancements in equipment and technology have facilitated the transition from surgical procedures to percutaneous techniques for removing embolized occluder devices. In this report, we present a case in which an Amplatzer septal occluder (ASO) device embolized to the descending thoracic aortic isthmus two days after implantation. The device was successfully retrieved using a percutaneous technique, and another ASO device was subsequently redeployed to the ASD. Regrettably, the patient experienced an intraoperative cardiac arrest. Despite prompt rescue efforts and recovery of vital signs, the patient still suffered postoperative sequelae. The main reason for occluder device migration in this case may have been the undersizing of the ASO device due to the operator's lack of caution.

Helicobacter macacae MazF interplays with Escherichia coli homologs and enhances antibiotic tolerance

BACKGROUND

Toxin-antitoxin systems are highly variable, even among strains of the same bacterial species. The MazEF toxin-antitoxin system is found in many bacteria and plays important roles in various biological processes such as antibiotic tolerance and phage defense. However, no interplay of MazEF systems between different species was reported.

MATERIALS AND METHODS

MazEF toxin-antitoxin system of Helicobacter macacae was examined in three Escherichia coli strains with and without endogenous MazEF knockout. In vivo toxicity, antibiotic tolerance, and live/dead staining followed by flowcytometry analysis were performed to evaluate the functionality and interplay of the toxin-antitoxin system between the two species.

RESULTS

Controlled ectopic expression of MazF of H. macacae (MazFhm) in E. coli did not affect its growth. However, in endogenous MazEF knockout E. coli strains, MazFhm expression caused a sharp growth arrest. The toxicity of MazFhm could be neutralized by both the antitoxin of MazE homolog of H.macacae and the antitoxin of MazE of E. coli, indicating interplay of MazEF toxin-antitoxin systems between the two species. Induced expression of MazFhm enhanced tolerance to a lethal dose of levofloxacin, suggesting enhanced persister formation, which was further confirmed by live/dead cell staining.

CONCLUSIONS

The MazEF toxin-antitoxin system of H. macace enhances persister formation and thus antibiotic tolerance in E. coli. Our findings reveal an interplay between the MazEF systems of H. macacae and E. coli, emphasizing the need to consider this interaction while evaluating the toxicity and functionality of MazF homologs from different species in future studies.

[Effect of Bushen Chushi() decoction combined with platelet-rich plasma on regulating TGF-β1 and Smad-1 expression in serum of knee osteoarthritis patient]

OBJECTIVE

To investigate the effect of Bushen Chushi decoction combined with platelet-rich plasma(PRP) to treat knee osteoarthritis(KOA) in early and middle stage and its regulation on TGF-β1 and Smad-1 expression in serum.

METHODS

Total of 45 patients with KOA in early and middle stage from May 2020 to April 2022 were treated and divided into control group and observation group. In control group, there were 30 patients including 12 males and 18 females, aged from 43 to 69 years old with an average of(57.3±6.5) years old and disease duration ranged from 1.5 to 5.0 years with an average of(3.8±1.7) years, and there were 8 cases in gradeⅠ, 13 cases in gradeⅡ, and 9 cases in grade Ⅲ according to Kellgren-Lawrence Grade, PRP 5 ml was injected into knee joint on the first day of No1, 3 week together for 2 times. In the observation group, there were 15 cases including 7 males and 8 females, aged from 45 to 70 years old with an average of (56.7±6.2) years old and disease duration ranged from 1.8 to 5.7 years with an average of (4.0±1.8) years, there were 4 cases in gradeⅠ, 9 cases in gradeⅡand 4 cases in grade Ⅲ according to the Kellgren-Lawrence Grade, PRP 5 ml were injected into knee joints that the time and frequency were the same as those in the control group, and at the same time Bushen Chushi decoction orally were taken 1 dose per day with a total of 28 doses. All patients were treated for four weeks. Visual analogue scale(VAS) and Lequesne MG score before and after treatment were used to evaluate improvement of knee pain and joint function. The TGF-β1 and Smad-1 levels in serum were measured before and after treatment in two groups. The incidence of complications in two groups was observed.

RESULTS

All patients were followed up for 26 to 30 days with an average of (28.0±0.6) days. There was no significant difference in VAS and knee Lequesne MG scores between two groups before treatment(P>0.05). The scores of VAS and knee Lequesne MG on the first day after treatment in both groups were lower than those before treatment(P<0.05). The VAS and knee Lequesne MG scores in observation group were lower than those in control group(P<0.05) on the first day after treatment. The TGF-β1 level in serum after treatment were higher significantly than that before treatment in two groups(P<0.05). After treatment, TGF-β1 level in serum in observation group were lower than those in control group with statistically significant differences(P<0.05). The Smad-1 levels in serum after treatment in observation group were higher significantly than that in control group(P<0.05). The levels of Smad-1 were not statistically significant between before and after treatment(P>0.05). There was no significant difference in postopertaive complications between two groups (P>0.05).

CONCLUSION

The efficacy of Bushen Chushi decoction combined with PRP in treatment of early and middle KOA is better than that of PRP injection alone. The combined treatment could reduce TGF-β1 level and increase Smad-1 level in serum, which may be a mechanism to inhibit inflammation and alleviate cartilage degeneration to some extent.

Long-Read- and Short-Read-Based Whole-Genome Sequencing Reveals the Antibiotic Resistance Pattern of Helicobacter pylori

The rates of antibiotic resistance of Helicobacter pylori are increasing, and the patterns of resistance are region and population specific. Here, we elucidated the antibiotic resistance pattern of H. pylori in a single center in China and compared short-read- and long-read-based whole-genome sequencing for identifying the genotypes. Resistance rates of 38.5%, 61.5%, 27.9%, and 13.5% against clarithromycin, metronidazole, levofloxacin, and amoxicillin were determined, respectively, while no strain was resistant to tetracycline or furazolidone. Single nucleotide variations (SNVs) in the 23S rRNA and GyrA/B genes revealed by Illumina short-read sequencing showed good diagnostic abilities for clarithromycin and levofloxacin resistance, respectively. Nanopore long-read sequencing also showed a good efficiency in elucidating SNVs in the 23S rRNA gene and, thus, a good ability to detect clarithromycin resistance. The two technologies displayed good consistency in discovering SNVs and shared 76% of SNVs detected in the rRNA gene. Taking Sanger sequencing as the gold standard, Illumina short-read sequencing showed a slightly higher accuracy for discovering SNVs than Nanopore sequencing. There are two copies of the rRNA gene in the genome of H. pylori, and we found that the two copies were not the same in at least 26% of the strains tested, indicating their heterozygous status. Especially, three strains harboring a 2143G/A heterozygous status in the 23S rRNA gene, which is the most important site for clarithromycin resistance, were found. In conclusion, our results provide evidence for an empirical first-line treatment for H. pylori eradication in clinical settings. Moreover, we show that Nanopore sequencing is a potential tool for predicting clarithromycin resistance. IMPORTANCE Helicobacter pylori resistance has been increasing in recent years. The resistance profile, which is important for empirical treatment, is region and population specific. We found high rates of resistance to metronidazole, clarithromycin, and levofloxacin in H. pylori in our center, while no resistance to tetracycline or furazolidone was found. These results provide a reference for local physicians prescribing antibiotics for H. pylori eradication. Nanopore sequencing recently appeared to be a promising technology for elucidating whole-genome sequences, which generates long sequencing reads and is time-efficient and portable. However, a relatively higher error rate of sequencing reads was also found. In this study, we compared Nanopore sequencing and Illumina sequencing for revealing single nucleotide variations in the 23S rRNA gene, which determines clarithromycin resistance, and we found that although there were a few false discoveries, Nanopore sequencing showed good consistency with Illumina sequencing, indicating that it is a potential tool for predicting clarithromycin resistance.

Targeting KRASG12V mutations with HLA class II-restricted TCR for the immunotherapy in solid tumors

KRAS mutation is a significant driving factor of tumor, and KRAS^G12V mutation has the highest incidence in solid tumors such as pancreatic cancer and colorectal cancer. Thus, KRAS^G12V neoantigen-specific TCR-engineered T cells could be a promising cancer treatment approach for pancreatic cancer. Previous studies had reported that KRAS^G12V-reactive TCRs originated from patients' TILs could recognized KRAS^G12V neoantigen presented by specific HLA subtypes and remove tumor persistently in vitro and in vivo. However, TCR drugs are different from antibody drugs in that they are HLA-restricted. The different ethnic distribution of HLA greatly limits the applicability of TCR drugs in Chinese population. In this study, we have identified a KRAS^G12V-specific TCR which recognized classII MHC from a colorectal cancer patient. Interestingly, we observed that KRAS^G12V-specific TCR-engineered CD4⁺ T cells, not CD8⁺ T cells, demonstrated significant efficacy in vitro and in xenograft mouse model, exhibiting stable expression and targeting specificity of TCR when co-cultured with APCs presenting KRAS^G12V peptides. TCR-engineered CD4⁺ T cells were co-cultured with APCs loaded with neoantigen, and then HLA subtypes were identified by the secretion of IFN-γ. Collectively, our data suggest that TCR-engineered CD4⁺ T cells can be used to target KRAS^G12V mutation presented by HLA-DPB1*03:01 and DPB1*14:01, which provide a high population coverage and are more suitable for the clinical transformation for Chinese, and mediate tumor killing effect like CD8⁺ T cells. This TCR hold promise for precision therapy in immunotherapy of solid tumors as an attractive candidate.

[Clinical features and genetic analysis of a case of Wiedemann-Steiner syndrome due to variant of KMT2A gene]

OBJECTIVE

To explore the clinical features and genetic etiology of a child with Wiedemann-Steiner syndrome.

METHODS

A child with WSS who was admitted to the Hematology Department of Tianjin Children's Hospital in May 2021 was selected as the subject. Clinical data of the child was collected. Peripheral blood samples were collected from the child and his parents for the extraction of genomic DNA. The child was subjected to whole exome sequencing, and candidate variant was verified by Sanger sequencing of the child and his parents.

RESULTS

The main clinical features of the child have included pancytopenia, growth and mental retardation, and facial dysmorphism. Whole exome sequencing revealed that the child has harbored a heterozygous variant of the KMT2A gene, namely c.7804delA (p.M2602Cfs*39). Sanger sequencing verified the variant to be de novo in origin. The variant was unreported previously and predicted to be pathogenic based on the guidelines of American College of Medical Genetics and Genomics (PVS1+PS2+PM2).

CONCLUSION

The heterozygous c.7804delA (p.M2602Cfs*39) variant of the KMT2A gene probably underlay the WSS in this child. Above finding has enriched the mutational spectrum and clinical phenotypes of the KMT2A gene.

Identification of a Novel Deep Intronic Variant by Whole Genome Sequencing Combined With RNA Sequencing in a Chinese Patient With Menkes Disease

Background: Menkes disease (MD) is a rare X-linked connective tissue disorder of copper metabolism caused by pathogenic variant(s) in ATP7A gene. The aim of the present study is to determine the clinical characteristics and molecular basis of one patient with MD.

Methods: One 10-month-old Chinese boy who met the clinical manifestations of MD was enrolled in this study. Whole genome sequencing (WGS) was performed in the patient in order to identify the variant(s), followed by Sanger sequencing. RNA sequencing (RNA-seq) from whole blood was subsequently applied to assess the effect of variant on transcription levels, and reverse transcriptase-polymerase chain reaction (RT-PCR) was performed for further validation. In addition, X chromosome inactivation (XCI) status of the patient’s mother at the DNA level was measured by capillary electrophoresis.

Results: The patient suffered from intermittent convulsions for more than 6 months, with psychomoto retardation and neurodegenerations. The patient also had curly hair, hypopigmented skin, cutis laxa, decreased muscle strength and hypotonia. MRI showed the intracranial arteries were tortuous with some “spiral” changes. The patient’s serum ceruloplasmin level was low. WGS revealed one novel hemizygous variant, c.2627-501C > T (NM_000,052.7), located in the deep intronic sequence of ATP7A gene. Sanger sequencing confirmed that the variant was inherited from his mother. RNA-seq confirmed the variant itself, and identified a pseudo-exon inserted between exons 12 and 13 in mRNA of ATP7A. The sequencing results of RT-PCR from the patient confirmed this finding, while neither of his parents detected aberrant splicing. The Capillary electrophoresis results showed that the patient’s mother had a skewed XCI.

Conclusion: Our finding of the variant enlarges the variant spectrum in the ATP7A gene. This is a novel deep intronic variant which leads to the activation of a pseudo-exons in the ATP7A gene, and it demonstrates the usefulness of WGS combined with RNA-seq, in terms of revealing disease-causing variants in non-coding regions. Furthermore, the fact that the deep intronic variants cause disease by the activation of pseudo-exon inclusion indicates that in MD this might be an important mechanism.

Chronic immune thrombocytopenia in a child with X-linked agammaglobulinemia-an uncommon phenotype

Autoimmune disorders are common in patients with primary immunodeficiency diseases (PIDs). However, the prevalence of autoimmunity is low in patients with X-linked agammaglobulinemia (XLA), mostly due to the absence of antibodies. Chronic or persistent immune thrombocytopenia (ITP), which is usually considered an antibody-mediated disease, is uncommon in patients with XLA. In this study, we detailly described a surprising autoimmune phenomenon, chronic ITP, in a small boy diagnosed with XLA. This is an interesting phenotype found in XLA, and it is helpful to understand the immune pathogenesis of autoimmunity in patients with XLA.

CCCH Zinc finger genes in Barley: genome-wide identification, evolution, expression and haplotype analysis

BACKGROUND

CCCH transcription factors are important zinc finger transcription factors involved in the response to biotic and abiotic stress and physiological and developmental processes. Barley (Hordeum vulgare) is an agriculturally important cereal crop with multiple uses, such as brewing production, animal feed, and human food. The identification and assessment of new functional genes are important for the molecular breeding of barley.

RESULTS

In this study, a total of 53 protein-encoding CCCH genes unevenly dispersed on seven different chromosomes were identified in barley. Phylogenetic analysis categorized the barley CCCH genes (HvC3Hs) into eleven subfamilies according to their distinct features, and this classification was supported by intron-exon structure and conserved motif analysis. Both segmental and tandem duplication contributed to the expansion of CCCH gene family in barley. Genetic variation of HvC3Hs was characterized using publicly available exome-capture sequencing datasets. Clear genetic divergence was observed between wild and landrace barley populations in HvC3H genes. For most HvC3Hs, nucleotide diversity and the number of haplotype polymorphisms decreased during barley domestication. Furthermore, the HvC3H genes displayed distinct expression profiles for different developmental processes and in response to various types of stresses. The HvC3H1, HvC3H2 and HvC3H13 of arginine-rich tandem CCCH zinc finger (RR-TZF) genes were significantly induced by multiple types of abiotic stress and/or phytohormone treatment, which might make them as excellent targets for the molecular breeding of barley.

CONCLUSIONS

Overall, our study provides a comprehensive characterization of barley CCCH transcription factors, their diversity, and their biological functions.

Upper Gastrointestinal Tract IrAEs: A Case Report About Sintilimab-Induced Acute Erosive Hemorrhagic Gastritis

INTRODUCTION

Immune checkpoint inhibitors (ICIs) have now become the standard therapy for malignancies like non-small cell lung cancer and classical Hodgkin's lymphoma. ICIs are associated with unique immune-related adverse events (irAEs) caused by dysregulated immune activation. Treatment of lower gastrointestinal (GI) tract irAEs, such as colitis, is more common. However, for upper gastrointestinal tract irAEs, there is a lack of consensus in terms of globally standardized disease classification and treatment guidelines. Here, we report a case of sintilimab-induced acute erosive hemorrhagic gastritis.

CASE PRESENTATION

A 54-year-old man with metastatic NSCLC (PT2N2M1 stage IV) underwent treatment with eight courses of sintilimab + bevacizumab, followed by maintenance therapy with sintilimab alone. However, he presented with epigastric pain and melena at the end of the first sintilimab treatment, and the symptoms occurred repeatedly after regular treatment with acute erosive hemorrhagic gastritis. Repeat esophagogastroduodenoscopy (EGD) showed severe hemorrhagic gastritis; symptomatic relief and improvement in EGD images were noted for as long as he was being treated with steroids, methylprednisolone sodium.

CONCLUSION

As far as we are aware, we here describe the first case of sintilimab-associated acute erosive hemorrhagic gastritis, an upper gastrointestinal toxicity event. Throughout the treatment progression, differential diagnosis, multidisciplinary discussion, and the use of immunosuppressants were instrumental in clarifying the diagnosis and were crucial to the prognosis of the patient and continued treatment with ICIs.

The synthesis and magnetic properties of carboxylic acid-derived 1,2,4-benzotriazinyl radicals and their coordination particles

Stable magnetic coordination particles based on π-conjugated 1,2,4-benzotriazinyl radical ligands were synthesized using a sonochemical method.

Giant Second Harmonic Generation Enhancement in a High-Q Doubly Resonant Hybrid Plasmon-Fiber Cavity System

A high-quality plasmon-fiber cavity in a doubly resonant configuration can exhibit second-harmonic generation (SHG) with over 5 orders of magnitude enhancement compared to gold nanoparticles on a fused silica substrate. Through coupling to a fiber cavity with the proper diameter, a high-quality (Q ≈ 160) resonance can be achieved in combination with a single gold nanoparticle. In a classical picture, where the incident electric field travels coherently Q times around the fiber during the nonlinear process, the high Q of the coupled mode aids in highly efficient SHG. We accomplish two feats: First, we analyze the Q factor dependence of the SHG efficiency, proving the expected Q⁴ dependence and thus confirming coherent E-field amplification in the fiber cavity. Second, we carefully adjust the fiber size further and tune the plasmon response of a gold nanoparticle to a high-Q cavity mode. We make sure that the second harmonic wavelength is simultaneously in resonance with a higher order fiber cavity mode, fulfilling the doubly resonant condition. As a result, a giant SH response with conversion efficiency up to 1.6 × 10^-5 is detected upon a pump intensity of 5 × 10⁸ W/cm² for 100 fs pump pulses around 840 nm incident wavelength. Additionally, the importance of the doubly resonant condition is proven by detuning the size of the fiber, which leads to a drastic drop in SHG efficiency. This disparity of the SHG efficiency can be observed even by eye, when monitoring the intensity changes of the visible SH light during detuning.

Decoupling the Positive and Negative Aging Processes of Perovskite Light-Emitting Diodes Using a Thin Interlayer of Ionic Liquid

A positive aging phenomenon, that is, enhancement of the electroluminescence performance at the beginning of electrical aging, is commonly observed for the state-of-the-art perovskite light-emitting diodes (PeLEDs). The origins of positive aging could fundamentally interfere with those of the operational deterioration processes of PeLEDs (namely negative aging), bringing difficulty in analyzing the degradation mechanisms. This work decouples the positive and negative aging processes of PeLEDs by inserting a thin ionic liquid interlayer between the hole-injection layer and the perovskite layer. This interlayer inhibits ions migration by passivating the halogen vacancies of perovskite films and suppresses interfacial exciton quenching, enabling us to decouple the positive and negative aging processes of PeLEDs while increasing the device efficiency. Inserting an ionic liquid interlayer is also demonstrated to be effective for iodide-based PeLEDs and applicable with the use of other ionic liquids. Our work provides an ideal system for fundamental studies on the degradation mechanisms of PeLEDs.

[Expression profile of intervertebral disc degeneration-specific genes: a transcriptome sequencing-based analysis]

OBJECTIVE

To identify new therapeutic targets for intervertebral disc degeneration (IDD) by analyzing gene variations in IDD.

OBJECTIVE

We analyzed surgical samples of intervertebral disc from 4 patients with IDD and 3 patients with non-IDD using RNA sequencing (RNA-seq) technology to identify significant differentially expressed genes (DEGs) in IDD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were utilized for gene enrichment studies to acquire the key genes and signal pathways during IDD progression. The differential expressions of the identified genes in IDD were validated in clinical samples with qRT-PCR.

OBJECTIVE

The transcriptome profile revealed 512 significant DEGs, which were enriched in terms of keratinization, extracellular matrix (ECM) components, growth factor binding, and inflammatory chemotaxis in GO analysis. The top 10 terms of KEGG enrichment included amoebiasis, viral protein interaction with cytokine and cytokine receptor, ECM-receptor interaction, IL-17 signaling pathway, cytokine-cytokine receptor interaction, TNF signaling pathway, AGE-RAGE signaling pathway in diabetic complications, PI3K-Akt signaling pathway, chemokine signaling pathway and estrogen signaling pathway. Thirteen DEGs selected as the targets for qRT-PCR validation showed significant differential expressions in IDD (P < 0.001), and their expression trends were all consistent with the results of RNA-seq. Among these genes, 10 genes showed significant intergroup fold change (Log2FoldChange>1).

OBJECTIVE

ECM, growth factors, collagen components, inflammatory chemokines and such signal pathways as TNF-α and PI3K-Akt all have important contributions to IDD progression and may thus serve as new therapeutic targets for treatment of IDD.

Efficient and Stable Organic Light-Emitting Diodes Employing Indolo[2,3-b]indole-Based Thermally Activated Delayed Fluorescence Emitters

Triplet excitons can be effectively harvested in organic light-emitting diodes employing thermally activated delayed fluorescence (TADF) molecules as the emitter and host. A design strategy for blue and green emitters with small S₁-T₁ splitting (ΔE_ST) is to construct a donor-acceptor (D-A) type molecule with moieties combining a high T₁ level with a strong electron-donating/withdrawing character. Here, we report a new kind of TADF emitter with an indolo[2,3-b]indole (IDID) donor. In comparison to other reported indolocarbazole and indoloindole donors, IDID has a higher T₁ level, which is comparable to that of the classical donor 9,9-dimethyl-9,10-dihydroacridine (DMAC) for blue TADF emitters. The sky-blue and green TADF emitters based on the IDID donor and a phenyltriazine acceptor exhibit high photoluminescence quantum yields (0.78-0.92) and short TADF lifetimes (1.1-1.7 μs) in doped films. Devices employing these IDID-based emitters offer an external quantum efficiency of 19.2%, which is comparable to that obtained for a device employing an analogous compound with a DMAC donor, while the stability of the former is higher than that of the latter owing to the just-right D-A twisting angles (∼59°) in the IDID-based emitters leading to a balance between ΔE_ST and the fluorescence rate. The utilization of host materials with a similar polarity to the emitter is found to be an effective strategy to improve device stability.

A novel de novo MYH9 mutation in MYH9-related disease: A case report and review of literature

INTRODUCTION

MYH9-related disease (MYH9-RD) is a rare autosomal dominant disorder caused by mutations in MYH9, which is responsible for encoding nonmuscle myosin heavy chains IIA (NMMHCIIA). MYH9-RD is clinically characterized by congenital macrothrombocytopenia, granulocyte inclusions variably associated with the risk of developing progressive sensorineural deafness, cataracts and nephropathy.

PATIENT CONCERNS

A 5-year-old boy had a history of a mild bleeding tendency and chronic thrombocytopenia, first identified at four months of age. No other family members were noted to have similar clinical features or hematologic disorders.

DIAGNOSES

The boy was diagnosed with MYH9-RD. Light microscopic examination of peripheral blood films (Wright-Giemsa stain) showed marked platelet macrocytosis with giant platelets and basophilic Döhle-like inclusions in 83% of the neutrophils. Immunofluorescence analysis disclosed a type II pattern, manifested by neutrophils which contained several circle-to-oval shaped cytoplasmic NMMMHCA-positive granules. Sequencing analysis of MYH9-RD genes was carried out and revealed a novel missense mutation of c.97T>G (p.W33G) in the patient but not in his parents.

INTERVENTION

No treatment is necessary. Recognition of MYH9-RD is important to Avoiding unnecessary and potentially harmful treatments.

OUTCOMES

The patient's condition remained stable during the follow-up.

CONCLUSIONS

As a result of identifying this missense mutation in this particular case, we have added c.97T>G (p.W33G) to the broad spectrum of potential MYH9 mutations.

Pyrazine-Based Blue Thermally Activated Delayed Fluorescence Materials: Combine Small Singlet-Triplet Splitting With Large Fluorescence Rate

Metal-free thermally activated delayed fluorescence (TADF) emitters have emerged as promising candidate materials for highly efficient and low-cost organic light-emitting diodes (OLEDs). Here, a novel acceptor 2-cyanopyrazine is selected for the construction of blue TADF molecules via computer-assisted molecular design. Both theoretical prediction and experimental photophysical data indicate a small S₁-T₁ energy gap (ΔE_ST) and a relative large fluorescence rate (k_F) in an o-phenylene-bridged 2-cyanopyrazine/3,6-di-tert-butylcarbazole compound (TCzPZCN). The k_F value of 3.7 × 10⁷ s⁻¹ observed in a TCzPZCN doped film is among the highest in the TADF emitters with a ΔE_ST smaller than 0.1 eV. Blue TADF emission is observed in a TCzPZCN doped film with a short TADF lifetime of 1.9 μs. The OLEDs using TCzPZCN as emitter exhibit a maximum external quantum efficiency (EQE) of 7.6% with low-efficiency roll-off. A sky-blue device containing a derivative of TCzPZCN achieves an improved EQE maximum of 12.2% by suppressing the non-radiative decay at T₁.

Ultranarrow Second-Harmonic Resonances in Hybrid Plasmon-Fiber Cavities

We demonstrate second-harmonic generation with ultranarrow resonances in hybrid plasmon-fiber cavities, formed by depositing single-crystalline gold nanorods onto the surface of tapered microfibers with diameters in the range of 1.7-1.8 μm. The localized surface plasmon mode of the single gold nanorod efficiently couples with a whispering gallery mode of the fiber, resulting in a very narrow hybrid plasmon-fiber resonance with a high quality factor Q of up to 250. When illuminated with a tunable 100 fs laser, a sharp SHG peak narrower than half of the spectral width of the impinging laser emerges, superimposed on a broad multiphoton photoluminescence background. The enhancement of the SHG peak of the hybrid system is typically 1000-fold when compared to that of a single gold nanorod alone. Tuning the laser over the hybrid resonance enables second-harmonic spectroscopy and yields an ultranarrow line width as small as 6.4 nm. We determine the second-harmonic signal to rise with the square of the laser power, while the multiphoton photoluminescence background rises with powers between 4 and 6, indicating a very efficient higher-order process. A coupled anharmonic oscillator model is able to describe the linear as well as second-harmonic resonances very well. Our work will open the door to the simultaneous utilization of narrow whispering gallery resonances together with high plasmonic near-field enhancement and should allow for nonlinear sensing and extremely efficient nonlinear light generation from ultrasmall volumes.

An Empirical Study of E-Service Quality and User Satisfaction of Public Service Centers in China

This article describes how as part of the reform of the administrative system of China, most local governments have set up public service centers; meanwhile, ICT (Information and Communication Technology) has been commonly applied to make e-services more convenient, efficient and transparent. However, the existing studies in the Chinese context are mostly qualitative and the relationship between service quality and citizen satisfaction has not been tested. This article adopted the D&M model to develop an e-service quality model and tested the impact of service quality on citizen satisfaction. A survey was conducted and 364 valid questionnaires were analyzed. The results showed that the data fit the model well. Most of the hypotheses formulated in this article was proven. Additionally, an important finding was that the impact of service quality on specific satisfaction is stronger than that of information quality and system quality, which indicates that face-to-face services cannot simply be substituted by electronic systems. Both the theoretical and practical implications of the findings were discussed.

Acquirers’ prior related knowledge and post-acquisition integration

Purpose

This paper examines the role of acquirers’ prior related knowledge in the post-acquisition integration process. The purpose of this paper is to identify what constitutes the key prior related knowledge that can contribute to the reverse knowledge transfer following Chinese firms’ outward mergers and acquisitions (M&As) to Europe, and explain how prior related knowledge affects such transfer of knowledge.

Design/methodology/approach

The authors employ a multiple case study approach. Semi-structured interviews were conducted from February 2012 to June 2013 with 24 managers.

Findings

The authors find that, in addition to knowledge about the target, prior international business experience, R&D capability, and industrial capabilities are key components of acquirers’ prior related knowledge that can contribute to the success of M&A integration and post-acquisition reverse knowledge transfer. Indeed, Chinese acquirers’ prior related knowledge can influence the reverse knowledge transfer from acquired firms to acquirers by directly improving acquirers’ absorptive capacity and building a harmonious organisational climate to facilitate such transfer.

Originality/value

This paper contributes to the absorptive capacity and the cross-border M&A literature. It extends the current knowledge on the key components of an acquirer’s prior related knowledge in the outward M&A by Chinese firms. It also uncovers how post-acquisition reverse knowledge transfer is affected by acquirers’ prior related knowledge.

Rotavirus-associated immune thrombocytopenic purpura in children: A retrospective study

Certain studies have previously indicated that an association may exist between rotavirus infection and primary immune thrombocytopenic purpura (ITP). The present retrospective study aimed to investigate whether rotavirus may cause ITP in children. Firstly, the incidence of ITP in children with or without rotavirus diarrhea was compared. A 14.58% incident rate was observed in children with rotavirus diarrhea compared with a 7.22% incident rate in children without rotavirus diarrhea. Subsequently, the clinical features of ITP children with or without rotavirus infection were compared. The results indicated that ITP children with rotavirus infection were significantly younger, showed significantly decreased mean platelet volume (MPV) levels and presented a significantly higher frequency of bleeding score of 3 against ITP children without rotavirus infection. In conclusion, these findings suggest that rotavirus serves a causative role in ITP.

A photoswitchable diarylethene heterodimer for use as a multifunctional logic gate

A photoswitchable diarylethene heterodimer was prepared and its applications to logic gates were successfully demonstrated.

Demonstration of multi-wavelength tunable fiber lasers based on a digital micromirror device processor

Based on a digital micromirror device (DMD) processor as the multi-wavelength narrow-band tunable filter, we demonstrate a multi-port tunable fiber laser through experiments. The key property of this laser is that any lasing wavelength channel from any arbitrary output port can be switched independently over the whole C-band, which is only driven by single DMD chip flexibly. All outputs display an excellent tuning capacity and high consistency in the whole C-band with a 0.02 nm linewidth, 0.055 nm wavelength tuning step, and side-mode suppression ratio greater than 60 dB. Due to the automatic power control and polarization design, the power uniformity of output lasers is less than 0.008 dB and the wavelength fluctuation is below 0.02 nm within 2 h at room temperature.

Anatomical research on the subacromial interval following implantation of clavicle hook plates

This article aimed to explore whether hook plate implantation significantly narrowed the subacromial space. 24 shoulder joints were implanted with clavicle hook plates. A Vernier caliper was used to measure the length and thickness of the acromion. In addition, the length and thickness of the hook of the plate were measured. The data from all measurements recorded were divided into 2 groups Group A, the length group: the length of acromion and the hook, and Group B, the thickness group: the thickness of acromion and the depth of hook. There are significant statistical differences when comparing between the subgroups within each group. The depth of the hook exceeds the thickness of the acromion (12.41±2.80 mm vs. 10.44±2.59 mm, respectively), the hook plate implantation significantly narrowed the subacromial space by 1.97±1.19 mm (p<0.01), and the length of the hook was shorter than that of the acromion by 9.75±3.64 mm (p<0.01). Our findings revealed that the hook plate with only 3 depths could not match the acromion satisfactorily and the hook plate implantation significantly narrowed the subacromial space. A hook plate with a variable depth, which can match better with patient's anatomy, is worthy of further investigation in the future.

[Effects of intravenous transplantation of human umbilical cord blood mononuclear cells combined compound Danshen dripping pills on the microenvironment and apoptosis in the myocardium of the rabbits with acute myocardial infarction]

OBJECTIVE

To explore the effects of compound Danshen dripping pills (CDDP) and CDDP combined with transplantation of human umbilical cord blood cells (HUMNCs) on the inflammatory response, oxidative stress, myocardial cell apoptosis and cardiac function, and also to investigate the possible mechanisms of the combined therapy in the acute myocardial infarction (AMI).

METHODS

Rabbit model of AMI successfully established by ligation of the left anterior coronary artery (LAD). Forty rabbits were randomly divided into 4 groups (n=10 per group): a control group, injected with 0.5 mL of saline in 24 h after AMI and then gavaged with 5 mL of saline daily; a CDDP group, injected with saline 0.5 mL after AMI and then gavaged with CDDP (270 mg/d) daily; a transplantation group, injected with 0.5 mL of saline contained 3 × 10(7) HUCBMCs [labeled with green fluorescent protein (GFP)] and then gavaged with 5 mL of saline daily; a combined group, injected with 0.5 mL of saline contained 3 × 10(7) HUCBMCs (labeled with GFP) and then gavaged with CDDP (270 mg/d) daily. Cardiac function index such as left ventricular fractional shorting (LVFS) and ejection fraction(LVEF) were measured by echocardiography; the pathological changes were observed by HE staining and the white blood cells in the myocardium were determined by light microscopy. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in myocardium were detected by nitrotetrazolium blue chloride (NBT) and thiobarbituric acid colorimetric measurement respectively. The number of transplanted cells in the myocardium was examined by GFP positive cells counted with fluorescence microscopy.

RESULTS

1) Compared with the control group (at 1 or 4 week), LVEF and LVFS were significant improved in the CDDP group, the transplantation group and the combined groups (all P<0.05), the improvement degree of cardiac function in the combined group was the most significance. There was no significant difference between the CDDP group and the transplantation group. 2) Compared with the control group (at 1 or 4 week), the number of white blood cell, myocardial cell apoptosis ratio were decreased significantly in the CDDP group, the transplantation group and the combined groups (all P<0.05), this decrease in the combined group was the most significance, and there was no significant difference between the CDDP group and the transplantation group. 3) Compared with control (at 4 week), the SOD activity was increased significantly, and MDA content in myocardium was decreased in the CDDP group, this change in the combined group was the most significance. 4) GFP-positive cells were found to be present in the peri-myocardial infarction area in the transplantation group and the combined group at 1, 4 weeks post-transplantation. The number of the GFP positive cells in the combined group was more than that in the transplantation group (P<0.05).

CONCLUSION

The intravenous transplantation of HUMNCs combined with the CDDP in the treatment of rabbits with AMI could increase the survival rate of transplanted cells and inhibit the myocardial cell apoptosis, therefore improve the heart function. The possible mechanism of the combined treatment may be involved in the inhibition of the inflammatory response and oxidative stress in the myocardium following AMI.

Enhanced therapeutic effects on acute myocardial infarction with multiple intravenous transplantation of human cord blood mononuclear cells

BACKGROUND

Cell transplantation of human cord blood mononuclear progenitor cells (HCBMCs) is a new treatment that could restore cardiac functions after acute myocardial infarction (AMI). We hypothesize that multiple doses of HCBMCs might increase homing of transplanted cells to infarcted region, and improve outcome of AMI via inhibition of ischemic-induced inflammatory responses.

METHODS AND RESULTS

HCBMCs were injected intravenously to rabbits that previously underwent ligation of left anterior coronary artery (LAD). Single dose of HCBMCs was intravenously delivered on the 7th day or multiple doses of HCBMCs were delivered on the 7th, 9th, 11th and 13th day after AMI. Homing of HCBMCs was determined by 5-bromodeoxyuridine (BrdU) labeling. The amount of grafted cells homed and retained in the infarcted area was significantly increased in the rabbits that received multiple doses. More viable cardiomyocytes and less collagen deposition were observed also in the group with more injections. Cardiac functions were assessed by echocardiography and hemodynamics. Multiple doses of HCBMCs showed significant benefits in preservation of cardiac functions. In infarcted myocardium, multiple transplantations of HCBMCs showed a significant increase in the myocardial level of anti-inflammatory IL-10 and a marked decrease in the level of the pro-inflammatory IL-6.

CONCLUSIONS

Multiple injections of HCBMCs markedly increased the amount of grafted cells, beneficially improving cardiac functions after AMI. The findings suggest that multiple doses of HCBMCs might be a novel strategy in the cell therapy for AMI.

A 1.1Mb deletion in distal 13q deletion syndrome region with congenital heart defect and postaxial polydactyly: additional support for a CHD locus at distal 13q34 region

13q deletion syndrome is a rare genetic disorder, especially for group 3 deletion (13q33-q34 deletion). Previously we described a patient with congenital heart defect and mental retardation and proposed that a distal 6Mb region might contain the causative gene of congenital heart defect. Here we present a new patient with congenital heart defects (CHD), hand and foot anomalies and mild mental retardation. We identified a 1.1Mb deletion at chromosome 13q34 with high resolution SNP-array BeadChips (HumanOmni1-Quad, Illumina, USA). This chromosome region contains ten annotated genes, including GRK1, TFDP1, RASA3 and GAS6. To our knowledge, this represents the smallest 13q34 deletion identified to date. Our study provides additional support that distal 13q34 deletion region might contain key gene(s) responsible for cardiac development.

[A neuropsychologic study in migraine patients]

A neuropsychologic test battery (nine kinds, eighteen items) was administered to 16 patients with classic migraine and 32 with common migraine in between attacks, 20 patients with functional headache and 20 physically and mentally healthy volunteers were sustained the test battery as control. The results suggested that the patients of both migraine groups had higher nervous dysfunction in motor, perception, memory, abstract thought, attention and information processing, statistic analysis showed significant difference between both migraine groups and normal control group. The higher nervous dysfunction became worse with the prolongation of course of migraine.

Distribution of red cell blood group systems in Yi, Tibetan and Manchu ethnic groups in China

A survey on distribution of ten red cell blood group systems was carried out in 1985 in the Yi, Tibetan and Manchu nationalities in China. Significant differences were found in the distribution of Rh, MNSs, P and especially in the ABO system, while no significant difference was found for Diego, Duffy, Kell, Kidd and XG systems. The DI*a gene frequency was about 0.03, FY*a rather high (0.94), KEL*K extremely low (0.005) and JK*a was about 0.4. In the three nationalities under study, Yi is characterized by high frequencies of the alleles A, M and CDe and by the absence of CDE and Cde. Tibetans show a high frequency of O and a relatively high frequency of P*P1, while Manchus have the lowest frequency of M and in particular of MS.