Peroxiredoxin II regulates exosome secretion from dermal mesenchymal stem cells through the ISGylation signaling pathway

BACKGROUND

Exosomes are small extracellular vesicles that play important roles in intercellular communication and have potential therapeutic applications in regenerative medicine. Dermal mesenchymal stem cells (DMSCs) are a promising source of exosomes due to their regenerative and immunomodulatory properties. However, the molecular mechanisms regulating exosome secretion from DMSCs are not fully understood.

RESULTS

In this study, the role of peroxiredoxin II (Prx II) in regulating exosome secretion from DMSCs and the underlying molecular mechanisms were investigated. It was discovered that depletion of Prx II led to a significant reduction in exosome secretion from DMSCs and an increase in the number of intracellular multivesicular bodies (MVBs), which serve as precursors of exosomes. Mechanistically, Prx II regulates the ISGylation switch that controls MVB degradation and impairs exosome secretion. Specifically, Prx II depletion decreased JNK activity, reduced the expression of the transcription inhibitor Foxo1, and promoted miR-221 expression. Increased miR-221 expression inhibited the STAT signaling pathway, thus downregulating the expression of ISGylation-related genes involved in MVB degradation. Together, these results identify Prx II as a critical regulator of exosome secretion from DMSCs through the ISGylation signaling pathway.

CONCLUSIONS

Our findings provide important insights into the molecular mechanisms regulating exosome secretion from DMSCs and highlight the critical role of Prx II in controlling the ISGylation switch that regulates DMSC-exosome secretion. This study has significant implications for developing new therapeutic strategies in regenerative medicine. Video Abstract.

[A case of combined oxidative phosphorylation deficiency 32 caused by MRPS34 gene variation and literature review]

Objective: To investigate the clinical features and genetic features of combined oxidative phosphorylation deficiency 32 (COXPD32) caused by MRPS34 gene variation. Methods: The clinical data and genetic test of a child with COXPD32 hospitalized in the Department of Neurology, Children's Hospital, Capital Institute of Pediatrics in March 2021 were extracted and analyzed. A literature search was implemented using Wanfang, China biology medicine disc, China national knowledge infrastructure, ClinVar, human gene mutation database (HGMD) and Pubmed databases with the key words "MRPS34" "MRPS34 gene" and "combined oxidative phosphorylation deficiency 32" (up to February 2023). Clinical and genetic features of COXPD32 were summarized. Results: A boy aged 1 year and 9 months was admitted due to developmental delay. He showed mental and motor retardation, and was below the 3^rd percentile for height, weight, and head circumference of children of the same age and gender. He had poor eye contact, esotropia, flat nasal bridge, limbs hypotonia, holding instability and tremors. In addition, Grade Ⅲ/6 systolic murmur were heard at left sternal border. Arterial blood gases suggested that severe metabolic acidosis with lactic acidosis. Brain magnetic resonance imaging (MRI) showed multiple symmetrical abnormal signals in the bilateral thalamus, midbrain, pons and medulla oblongata. Echocardiography showed atrial septal defect. Genetic testing identified the patient as a compound heterozygous variation of MRPS34 gene, c.580C>T (p.Gln194Ter) and c.94C>T (p.Gln32Ter), with c.580C>T being the first report and a diagnosis of COXPD32. His parents carried a heterozygous variant, respectively. The child improved after treatment with energy support, acidosis correction, and "cocktail" therapy (vitaminB₁, vitaminB₂, vitaminB₆, vitaminC and coenzyme Q10). A total of 8 cases with COXPD32 were collected through 2 English literature reviews and this study. Among the 8 patients, 7 cases had onset during infancy and 1 was unknown, all had developmental delay or regression, 7 cases had feeding difficulty or dysphagia, followed by dystonia, lactic acidosis, ocular symptoms, microcephaly, constipation and dysmorphic facies(mild coarsening of facial features, small forehead, anterior hairline extending onto forehead,high and narrow palate, thick gums, short columella, and synophrys), 2 cases died of respiratory and circulatory failure, and 6 were still alive at the time of reporting, with an age range of 2 to 34 years. Blood and (or) cerebrospinal fluid lactate were elevated in all 8 patients. MRI in 7 cases manifested symmetrical abnormal signals in the brainstem, thalamus, and (or) basal ganglia. Urine organic acid test were all normal but 1 patient had alanine elevation. Five patients underwent respiratory chain enzyme activity testing, and all had varying degrees of enzyme activity reduction. Six variants were identified, 6 patients were homozygous variants, with c.322-10G>A was present in 4 patients from 2 families and 2 compound heterozygous variants. Conclusions: The clinical phenotype of COXPD32 is highly heterogenous and the severity of the disease varies from development delay, feeding difficulty, dystonia, high lactic acid, ocular symptoms and reduced mitochondrial respiratory chain enzyme activity in mild cases, which may survive into adulthood, to rapid death due to respiratory and circulatory failure in severe cases. COXPD32 needs to be considered in cases of unexplained acidosis, hyperlactatemia, feeding difficulties, development delay or regression, ocular symptoms, respiratory and circulatory failure, and symmetrical abnormal signals in the brainstem, thalamus, and (or) basal ganglia, and genetic testing can clarify the diagnosis.

Identification of Hub Genes and Upstream Regulatory Factors Based on Cell Adhesion in Triple-negative Breast Cancer by Integrated Bioinformatical Analysis

BACKGROUND/AIM

Triple-negative breast cancer (TNBC) is characterized by metastasis and invasion, as well as poor prognosis, with chemotherapy being the main treatment option. Cell adhesion regulates tumorigenesis and new blood vessel formation. Thus, accurately identifying effective targets for TNBC and cell adhesion is challenging. Herein, we screened for differentially expressed genes between TNBC and normal cancer-free tissues to identify genes contributing to TNBC.

MATERIALS AND METHODS

Microarray data were obtained using a comprehensive gene-expression database. We used Database for Annotation, Visualization and Integrated Discovery, Kyoto Encyclopedia of Genes and Genomes and Functional Enrichment (FunRich) to perform Gene Ontology functional enrichment and predict signal pathways. The protein interaction network was predicted using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and Cytoscape v. 3.8.2. for visualization of results. TargetScan, miRanda, miRDB, miRWalk and RNA22 were used to predict miRNAs regulating key genes, and long non-coding RNAs (lncRNAs) regulating miRNAs were predicted using StarBase V2.0 from a comprehensive gene-expression database.

RESULTS

Differentially expressed genes were mainly concentrated in the biological process of cell-cell adhesion. The protein-protein interaction network identified eight hub genes: Fibronectin 1 (FN1), Rac family small GTPase 1 (RAC1), heat-shock protein 90 alpha family class B member 1 (HSP90AB1), tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ), heat-shock protein family A member 8 (HSPA8), IQ motif containing GTPase-activating protein 1 (IQGAP1), CD44 molecule (CD44), and catenin beta 1 (CTNNB1). miRNAs related to TNBC occurrence and development were hsa-miR-142-5p, hsa-miR-144, hsa-miR-28-5p, hsa-miR-548d-3p, hsa-miR-587, hsa-miR-641, and hsa-miR-708. StarBase v2.0 predicted 12 lncRNAs, namely NEAT1, XIST, OIP5-AS1, MALAT1, AL035425.3, NORAD, AL391069.4, AC118758.3, AC026362.1, AC009065.4, AC016876.2, and AC093010.3, as upstream molecules that regulate miRNAs and which may regulate TNBC.

CONCLUSION

Overall, mRNA-miRNA-lncRNA interactions appear to play a role in TNBC development.

Induction of Targeted Differentiation of Dermal Mesenchymal Stem Cells Into Neural Lineage According to Peroxiredoxin II Expression

BACKGROUND/AIM

To optimize the therapeutic potential of stem cells in stem cell therapy for neurological diseases, it is crucial to enhance the differentiation, migration, and neural network formation of stem cells, and to eliminate uncertain cell differentiation and proliferation factors. Several studies have shown that reactive oxygen species (ROS) are important factors in the regulation of neurogenesis, and Prx II (Peroxiredoxin II) is a gene that regulates ROS.

MATERIALS AND METHODS

As the entry point in this study to conduct a bioinformatics analysis of the sequencing results of Prx II^+/+ dermal mesenchymal stem cells (DMSCs) and Prx II^-/- DMSCs. lncRNA/miRNA/mRNA networks were then constructed and preliminarily verified in RT-qPCR experiments.

RESULTS

In this study, a total of 11 hub genes (Gria1, Nrcam, Sox10, Snap25, Cntn2, Dlg2, Ngf, Ntrk3, Amph, Syt1, and Cd24a), eight miRNAs (miRNA-4661, miRNA-34a, miRNA-185, miRNA-34b-5p, miRNA-34c, miRNA-449a, miRNA-449b, miRNA-449c) and 12 lncRNAs (Dubr, Gas5, Gm20427, Gm26917, Gm42547, Gm8066, Kcnq1ot1, Malat1, Mir17hg, Neat1, Rian, and Tug1) were predicted in lncRNA/miRNA/mRNA network.

CONCLUSION

The regulatory mechanism of Prx II in the differentiation of DMSCs into neurons through ROS was explored, and a theoretical basis was determined that can be applied in future research on nervous system diseases and the clinical applications of stem cells.

Bioinformatics Analysis of Novel Targets for Treating Cervical Cancer by Immunotherapy Based on Immune Escape

BACKGROUND/AIM

Cervical cancer (CC) is a high-risk disease in women, and advanced CC can be difficult to treat even with surgery, radiotherapy, and chemotherapy. Hence, developing more effective treatment methods is imperative. Cancer cells undergo a renewal process to escape immune surveillance and then attack the immune system. However, the underlying mechanisms remain unclear. Currently, only one immunotherapy drug has been approved by the Food and Drug Administration for CC, thus indicating the need for and importance of identifying key targets related to immunotherapy.

MATERIALS AND METHODS

Data on CC and normal cervical tissue samples were downloaded from the National Center for Biotechnology Information database. Transcriptome Analysis Console software was used to analyze differentially expressed genes (DEGs) in two sample groups. These DEGs were uploaded to the DAVID online analysis platform to analyze biological processes for which they were enriched. Finally, Cytoscape was used to map protein interaction and hub gene analyses.

RESULTS

A total of 165 up-regulated and 362 down-regulated genes were identified. Among them, 13 hub genes were analyzed in a protein-protein interaction network using the Cytoscape software. The genes were screened out based on the betweenness centrality value and average degree of all nodes. The hub genes were as follows: ANXA1, APOE, AR, C1QC, CALML5, CD47, CTSZ, HSP90AA1, HSP90B1, NOD2, THY1, TLR4, and VIM. We identified the following 12 microRNAs (miRNAs) that target the hub genes: hsa-miR-2110, hsa-miR-92a-2-5p, hsa-miR-520d-5p, hsa-miR-4514, hsa-miR-4692, hsa-miR-499b-5p, hsa-miR-5011-5p, hsa-miR-6847-5p, hsa-miR-8054, hsa-miR-642a-5p, hsa-miR-940, and hsa-miR-6893-5p.

CONCLUSION

Using bioinformatics, we identified potential miRNAs that regulated the cancer-related genes and long noncoding RNAs (lncRNAs) that regulated these miRNAs. We further elucidated the mutual regulation of mRNAs, miRNAs, and lncRNAs involved in CC occurrence and development. These findings may have major applications in the treatment of CC by immunotherapy and the development of drugs against CC.

[Research progress of nervous system damage in Pompe disease]

Pompe disease, also known as glycogen storage disease type Ⅱ, is a rare autosomal recessive disease. With the application of enzyme replacement therapy, more and more patients with Pompe disease can survive to adulthood, and nervous system-related clinical manifestations gradually emerge. Nervous system involvement seriously affects the quality of life of patients with Pompe disease, and a systematic understanding of the clinical manifestations, imaging features and pathological changes of nervous system injury in Pompe disease is of great significance for the early identification and intervention of Pompe disease. This article reviews the research progress of neurological damage in Pompe disease.

[Diagnosis and treatment strategies of 56 cases of middle ear myoclonus]

Objective: To analyze the clinical characteristics and treatment of middle ear myoclonus. Methods: Fifty-six cases of middle ear myoclonus were enrolled in Shandong Provincial ENT Hospital, Shandong University from September 2019 to August 2021, including 23 males and 33 females. The age ranged from 6 to 75 years, with a median age of 35 years; Forty-seven cases were unilateral tinnitus, nine cases were bilateral tinnitus. The time of tinnitus ranged from 20 days to 8 years. The voice characteristics, inducing factors, nature (frequency) of tinnitus, tympanic membrane conditions during tinnitus, audiological related tests, including long-term acoustic tympanogram, stapedius acoustic reflex, pure tone auditory threshold, short increment sensitivity test, alternate binaural loudness balance test, loudness discomfort threshold, vestibular function examination, facial electromyography, and imaging examination were recorded. Oral carbamazepine and/or surgical treatment were used. The patients were followed up for 6-24 months and the tinnitus changes were observed. Results: Tinnitus was diverse, including stepping on snow liking sound, rhythmic drumming, white noise, and so on. The inducing factors included external sound, body position change, touching the skin around the face and ears, speaking, chewing and blinking, etc. Forty-four cases were induced by single factor and 9 cases were induced by two or more factors. There was no definite inducing factor in 1 case. One patient had tinnitus with epilepsy. One case of traumatic facial paralysis after facial nerve decompression could induce tinnitus on the affected side when the auricle moved. Tympanic membrane flutter with the same frequency as tinnitus was found in 12 cases by otoscopy, and the waveform with the same frequency as tinnitus was found by long-term tympanogram examination. There were 7 patients with no tympanic membrane activity by otoscopy, the 7 cases also with the same frequency of tinnitus by long-term tympanogram examination, but the change rate of the waveform was faster than that of the patients with tympanic membrane flutter. All patients with tinnitus had no change in hearing. One case of tinnitus complicated with epilepsy (a 6-year-old child) was treated with antiepileptic drug (topiramate) and tinnitus subsided. One case suffered from tinnitus after facial nerve decompression for traumatic facial paralysis was not given special treatment. Fifty-four cases were treated with oral drug (carbamazepine), of which 10 cases were completely controlled and 23 cases were relieved; 21 cases were invalid. Among the 21 patients with no effect of carbamazepine treatment, 8 patients were treated by surgery, 7 patients had no tinnitus after surgery, 1 patient received three times of operation, and the third operation was followed up for 6 months, no tinnitus occurred again. The other 13 cases refused the surgical treatment due to personal reasons. Conclusions: Middle ear myoclonus tinnitus and the inducing factors manifestate diversity. Oral carbamazepine and other sedative drugs are effective for some patients, and surgical treatment is feasible for those who are ineffective for medication.

Network analysis for the identification of hub genes and related molecules as potential biomarkers associated with the differentiation of bone marrow-derived stem cells into hepatocytes

The incidence of liver diseases has been increasing steadily. However, it has some shortcomings, such as high cost and organ donor scarcity. The application of stem cell research has brought new ideas for the treatment of liver diseases. Therefore, it is particularly important to clarify the molecular and regulatory mechanisms of differentiation of bone marrow-derived stem cells (BMSCs) into liver cells. Herein, we screened differentially expressed genes between hepatocytes and untreated BMSCs to identify the genes responsible for the differentiation of BMSCs into hepatocytes. GSE30419 gene microarray data of BMSCs and GSE72088 gene microarray data of primary hepatocytes were obtained from the Gene Expression Omnibus database. Transcriptome Analysis Console software showed that 1896 genes were upregulated and 2506 were downregulated in hepatocytes as compared with BMSCs. Hub genes were analyzed using the STRING and Cytoscape v 3.8.2, revealing that twenty-four hub genes, play a pivotal role in the differentiation of BMSCs into hepatocytes. The expression of the hub genes in the BMSCs and hepatocytes was verified by reverse transcription-quantitative PCR (RT-qPCR). Next, the target miRNAs of hub genes were predicted, and then the lncRNAs regulating miRNAs was discovered, thus forming the lncRNA-miRNA-mRNA interaction chain. The results indicate that the lncRNA-miRNA-mRNA interaction chain may play an important role in the differentiation of BMSCs into hepatocytes, which provides a new therapeutic target for liver disease treatment.

[Application of anterolateral thigh flap preforming tongue in patients with total glossectomy]

Objective: To investigate the efficacy of anterolateral thigh flap preforming tongue in patients with total glossectomy. Methods: A total of 27 patients with tongue cancer who underwent total glossectomy, neck lymph node dissection and anterolateral thigh flap transfer were collected from January 2019 to April 2021 in the Department of Oral and Maxillofacial Surgery at the Second Xiangya Hospital. All patients were males, the age ranged from 35-73 years. The patients were divided into experimental (14 cases) and control (13 cases) groups, based on whether the tongue was reconstructed. The clinical parameters of two groups were analyzed by independent sample t test or Fisher exact probability method. Results: The success rate of free flap was 100%, of the patients, 2 patients had cervical hematoma and 1 patient had wound infection postoperatively. There was no difference in speech (6.69±3.42 vs. 5.50±3.01, t=0.96, P=0.346) or swallowing (χ²=0.46, P=0.793) function between two groups at 1 month after surgery. However, the speech (24.94±7.43 vs. 18.44±6.30, t=2.48, P=0.020) and swallowing (χ²=6.97, P=0.008) functions in experimental group were significantly better than those in control group. No case was lost to follow-up. All patients were extubated after operation, with average time of 7.2 days in the experimental group and 7.7 days in the control group. The overall survival rate was 71.4% in the experimental group and 61.5% in the control group. Conclusion: The use of anterolateral thigh flap preforming tongue can improve the speech and swallowing functions in patients with total glossectomy and offer a novel method for tongue construction.

[Effects of subanesthetic dose of esketamine on opioid consumption after thoracoscopic surgery]

Objective: To investigate the effect of continuous intravenous infusion of subanesthetic dose of esketamine intraoperatively on postoperative opioid consumption in patients undergoing thoracoscopic surgery. Methods: A total of 71 patients with elective thoracoscopic lung surgery in the First Affiliated Hospital of Zhengzhou University from December 2020 to December 2021 were selected. Patients who were classified as grade Ⅰ or Ⅱ by the American Society of Anesthesiologists (ASA) and aged 18-70 years were included, including 32 males and 39 females, with a body mass index (BMI) of 18.5-30.0 kg/m². The patients were randomly divided into three groups: (1) Control group (group C, n=24): continuous intravenous infusion of normal saline at the same rate during surgery; (2) Subanesthetic dose of esketamine 0.125 mg·kg^-1·h^-1 group (group ES1, n=23): continuous intravenous infusion of esketamine at a rate of 0.125 mg·kg^-1·h^-1 during surgery; (3) Subanesthetic dose of esketamine 0.250 mg·kg^-1·h^-1 group (group ES2, n=24): continuous intravenous infusion of esketamine at a rate of 0.250 mg·kg^-1·h^-1 during surgery. The main outcome measures were the total consumptions of hydromorphone of 3 groups within 24 and 48 hours after surgery. The secondary outcome measures were the extubation time, length of postanesthesia care unit (PACU) stay, the time of first feeding, and the incidences of adverse effects within 24 h after surgery in 3 groups. Results: The 24 h postoperative consumption of hydromorphone in group C, ES1 and ES2 was (5.4±1.0) mg, (4.5±1.5) mg and (4.0±0.8) mg, respectively. Likewise, the 48 h postoperative consumption of hydromorphone was (9.7±2.2) mg, (9.0±3.0) mg and (7.7±1.8) mg, respectively. Compared with group C, the 24 h postoperative hydromorphone consumptions were significantly reduced in group ES1 and ES2 (both P<0.05). The extubation time, length of PACU stay and the time of first feeding after surgery in group C were (23±10) min,(70±12) min,(17±3) h,in group ES1 were (22±4) min,(69±11) min,(14±5) h,in group ES2 were (16±8) min,(58±12) min,(14±3) h, respectively. Compared with group C and group ES1, both of the extubation time and length of PACU stay were shortened in group ES2 (both P<0.05). Compared with group C, the first postoperative feeding time of group ES1 and ES2 was shortened (both P<0.05). There were no differences in the incidences of adverse effects at postoperative 24 h among 3 groups (all P>0.05). Conclusion: Continuously intravenous infusion of subanesthetic esketamine at a rate of 0.250 mg·kg^-1·h^-1 can significantly reduce the postoperative opioid consumption and improve the patient's outcomes.

[Family genetic analysis of paternal Dystrophin gene mutations in a case of female Duchenne muscular dystrophy]

A pedigree genetic analysis of a female Duchenne muscular dystrophy (DMD) inherited from paternal chimerism was conducted to explore the genetic diagnosis strategy. No large deletions/duplications was found in the DMD gene of the proband. Next-generation sequencing (NGS) results showed that the proband had a heterozygous mutation in the DMD gene c.4707C>A (p.C1569X). This locus has not been reported in the literature and is considered as a pathogenic mutation. Sanger sequencing revealed that the father of the proband carried the same mutation, and the mosaic ratio was about 17.7%. The specific enzyme digestion test showed that the proband had maternal skewed X-inactivation. DMD a recessive inherited disease of the X chromosome, exists in female patients, and very few of them are inherited from paternal origin. Female patients need to pay close attention to skewed X-inactivation and suspected new mutations. Mosaic is not excluded, especially the inheritance of paternal mosaicism with normal phenotype. Prenatal gene screening is necessary for reproduction.

Inhibitory Effect of Bovine Adipose-Derived Mesenchymal Stem Cells on Lipopolysaccharide Induced Inflammation of Endometrial Epithelial Cells in Dairy Cows

Endometritis is a disease that affects reproductive health in dairy cows and causes serious economic damage to the dairy industry world-wide. Although in recent years, the application of mesenchymal stem cell (MSC) therapy for the treatment of inflammatory diseases has attracted much attention, there are few reports of the use of MSCs in dairy cows. In the present study, our objective was to explore the inhibitory effects of bovine adipose-derived mesenchymal stem cells (bAD-MSCs) on lipopolysaccharide (LPS) induced inflammation in bovine endometrial epithelial cells (bEECs) along with the potential underlying molecular mechanisms. We characterized isolated bAD-MSCs using cell surface marker staining and adipogenic/osteogenic differentiation, and analyzed them using immunofluorescence, flow cytometry (surface marker staining), and adipogenic and osteogenic differentiation. Furthermore, to understand the anti-inflammatory effects of bAD-MSCs on LPS induced bEEC inflammation, we used a bAD-MSC/bEEC co-culture system. The results showed that bAD-MSC treatments could significantly decrease LPS induced bEEC apoptosis and pro-inflammatory cytokine expression levels, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Furthermore, our results showed that bAD-MSC treatments could also significantly downregulate LPS induced p38, IkB-a, and JAK1 phosphorylation and Bax protein expression levels, which are closely related to inflammatory progress and cellular apoptosis in bEECs. Our findings demonstrate that bAD-MSCs play an inhibitory role in LPS induced bEEC inflammation and provide new insights for the clinical therapy of endometritis in dairy cows.

Peroxiredoxin II with dermal mesenchymal stem cells accelerates wound healing

Peroxiredoxin II (Prx II) is involved in proliferation, differentiation, and aging in various cell types. However, Prx II-mediated stem cell regulation is poorly understood. Here, dermal mesenchymal stem cells (DMSCs), cell-growth factor-rich conditioned medium from DMSCs (DMSC-CM), and DMSC-derived exosomes (DMSC-Exos) were used to explore the regulatory role of Prx II in DMSC wound healing. Following treatment, wound healing was significantly decelerated in Prx II-/- DMSCs than in Prx II+/+ DMSCs. In vitro stimulation with 10 μM H2O2 significantly increased apoptosis in Prx II-/- DMSCs compared with Prx II+/+ DMSCs. The mRNA expression levels of EGF, b-FGF, PDGF-B, and VEGF did not significantly differ between Prx II-/- and Prx II+/+ DMSCs. Fibroblasts proliferated comparably when treated with Prx II+/+ DMSC-CM or Prx II-/- DMSC-CM. Wound healing was significantly higher in the Prx II-/- DMSC-Exos-treated group than in the Prx II+/+ DMSCs-Exos-treated group. Moreover, microRNA (miR)-21-5p expression levels were lower and miR-221 levels were higher in Prx II-/- DMSCs than in Prx II+/+ DMSCs. Therefore, our results indicate that Prx II accelerated wound healing by protecting DMSCs from reactive oxygen species-induced apoptosis; however, Prx II did not regulate cell/growth factor secretion. Prx II potentially regulates exosome functions via miR-21-5p and miR-221.

[A Meta-analysis on association between statins and colorectal cancer]

Objective: To explore the association between statins and colorectal cancer and provide evidence for the prevention of colorectal cancer. Methods: Literatures about statins and colorectal cancer published from January 2000 to January 2020 were retrieved from CNKI, Wanfang data, PubMed and Cochrane Library database. The literatures which met the inclusion criteria were collected, and the Newcastle-Ottawa Scale and Jadad score were used to assess the studies. Meta-analysis was performed with statistical software Revman 5.0 and Stata 12.1. Results: A total of 31 studies, involving more than 1.62 million subjects, were included in the analysis. The case-control study (RR=0.93, 95%CI: 0.88-0.98), the cohort study (RR=0.75, 95%CI: 0.63-0.88) and the randomized controlled trial (RR=0.79, 95%CI: 0.65-0.97) showed moderate protective effect of statins. Using statin <5 years (RR=0.86, 95%CI: 0.76-0.96), average daily dosage ≥34 mg (RR=0.81, 95%CI: 0.66-0.98) and lipid-soluble statins (RR=0.86, 95%CI: 0.74-0.99) also had preventive effect on colorectal cancer; while lovastatin (RR=1.07, 95%CI: 1.00-1.14) increased the risk of colorectal cancer. Conclusion: Statins have protective effect on colorectal cancer.

[Clinical and genetic characteristics of children with STXBP1 encephalopathy]

Objective: To investigate the clinical and genetic characteristics of developmental and epileptic encephalopathy (DEE) caused by syntaxin-binding protein 1 (STXBP1) gene mutation. Methods: The clinical data, gene variation and treatment outcome of 15 children with STXBP1 encephalopathy admitted to Children's Hospital Affiliated to Capital Institute of Pediatrics from January 2014 to June 2019 were analyzed retrospectively. Results: Among 15 patients, 11 were male and 4 were female, age ranged from 2 months to 69 months. The clinical manifestations of 14 children were epilepsy and developmental delay (DD) and the remaining one showed developmental delay without seizure. The onset age of epilepsy ranged from two days to 19 months and 11 of them experienced the first attack before 1 year of age. The common seizure types were epileptic spasms and tonic seizures. Seven patients were diagnosed with Ohtahara syndrome or West syndrome. Epileptic form discharges were observed in the interictal electroencephalograms (EEG) of 11 patients, including multifocal discharges, suppression-burst and hypsarrhythmia. The brain magnetic resonance imaging of 7 children were abnormal, including myelin dysplasia, less white matter, lack of corpus callosum or hypoplasia. The follow-up time ranged from 2 months to 57 months, after the last follow-up, 3 cases were seizure free, 6 children showed partial response and the other 5 patients had no response on multitherapy. Six of 8 patients showed good responses to levetiracetam (LEV) monotherapy or in combination with other antiepileptic drugs (AEDs). Vigabatrin (VGB) was applied to 5 patients with epileptic spasms and 4 of them showed response. All patients showed different degrees of developmental delay while four of them showed autistic features. STXBP1 gene mutations were identified in all cases and there were 15 types of gene variations, including 8 missense mutations, 1 nonsense mutation, 5 frame shift mutations and 1 complex mutation. Five novel mutations were unreported before, including c.1193A>G, c.172delG, c.1769C>T, c.1038_1039delCC, c.348_351dupTGAA. Conclusions: Development delay and epilepsy are the major and independent clinical phenotypes in children with STXBP1 encephalopathy. The variation of STXBP1 gene is mainly de novo. Levetiracetam and vigabatrin may be more effective in epilepsy control than other AEDs.

[Clinical features of children with myelin oligodendrocyte glycoprotein antibody-associated disorders]

OBJECTIVE

To study the clinical features and treatment outcome of children with myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorders (MOGAD).

METHODS

A retrospective analysis was performed for the clinical data of 28 children with MOGAD (with 38 demyelinating episodes).

RESULTS

Among the disease spectrums of 28 children with MOGAD, optic neuritis was the most common (12 cases, 43%), followed by acute disseminated encephalomyelitis (9 cases, 32%). Among the 38 demyelinating episodes in the 28 children, there were 29 cases (76%) of lesions in the acute stage on head magnetic resonance imaging (MRI), and most of these lesions were extensive or isolated subcortical white matter lesions. A total of 24 cases of spinal MRI results in the acute stage were recorded, among which there were 11 cases (46%) of spinal lesions. MRI abnormalities of the optic nerve were found in 18 cases of optic neuritis in the acute stage. Of the 28 children, 20 (71%) had an increase in white blood cell count in cerebrospinal fluid, with lymphocytes as the most common type of cells, and 3 children had an increase in protein. The titer of serum MOG antibody was 1:10-1:320 in the 28 children. All 28 children were administered with glucocorticoids, along with immunoglobulin in 18 children. The symptoms of 26 children (93%) were alleviated during follow-up, and only 2 children had neurological sequela of the optic function.

CONCLUSIONS

The clinical manifestations are diverse in children with MOGAD. Immunotherapy is effective and most children have a good prognosis.

[Analysis on monitoring results of occupational hazards in Yangzhou city from 2014 to 2018]

Objective: To undersand the monitor of occupational hazards in the enterprises in the past 5 years, as well as the distribution of occupational disease hazards and their dynamic changes in their respective jurisdictions, for providing scientific basis for prevention and control of occupational diseases in relevant departments. Methods: Taking the method of cluster sampling, select the monitoring results of the occupational disease hazard factors commissioned by the Municipal Center for Disease Control and Prevention from 2014 to 2018 and the annual monitoring data of the network of the occupational hazard declaration system of the Safety Supervision Bureau, using chi-square test, trend Statistical analysis was performed by chi-square test or Fisher exact probability method. Results: There were 461 testing companies in the past 5 years, with a total of 15, 186 monitoring points and 43428 samples. The pass rate was 94.32% (14324/15186) . The pass rate was increasing year by year from 2014 to 2017 (P<0.05) ; The pass rate of various occupational disease hazards surveillance were greater than 90% except the rate of physical factors. In 2014, the qualified rate of physical factors was the lowest, which was 86.99% (1558/1791) ; the production rate of different production scale enterprises in 2018 was higher than that of 2014. From 2014 to 2018, the number of inspection enterprises and the number of inspection points of the joint-stock economy and state-owned economic enterprises are both high, 58 (10091 points) and 71 (1830 points) respectively; The qualified rate of state-owned economy and collective economy monitoring is high, 98.36% (1800/1830) and 100% (74/74) respectively. It had reached more than 95%; The enterprises tested mainly from the economic development zone and Guangling, respectively accounting for 34.27% (158/461) and 33.84% (156/461) of the total number of enterprises. Which followed by the Hanjiang, accounting for 23.21% of the total number of enterprises (107/461) ; The monitoring enterprises were mainly distributed in the manufacturing and power industries, which accounted for 85.25% (393/461) and 6.07% (28/461) of the total number of enterprises, respectively. Conclusion: The monitoring rate of enterprises had been increasing year by year from 2014 to 2018. Noise was the main disease prevention and controlling factor in the area.In addition, micro-enterprises, individual economy and foreign-invested economy were the key targets for occupational health.

Cross-cultural adaptation and psychometric properties of the Chinese version of the Functional Remission of General Schizophrenia (FROGS) scale and the four-item version (mini-FROGS) among people with schizophrenia

OBJECTIVE

This study was designed to verify the cross-cultural psychometric properties of the Functional Remission of General Schizophrenia (FROGS) scale and the four-item version (mini-FROGS) in Chinese schizophrenic individuals.

METHODS

Item clustering analysis was used to show the clustering relationship among items. Confirmatory factor analysis (CFA) was used to test the structural validity of the scale. The Global Assessment of Functioning (GAF) was used as a criterion to test convergent validity. The receiver operating characteristic curve (ROC) and the area under the ROC curve (ROC-AUC) were calculated to test the sensitivity and specificity of FROGS and mini-FROGS for functional assessment. Fifty participants were randomly selected for retest at two-month intervals.

RESULTS

A total of 228 schizophrenia individuals were enrolled in our study. The results of the item clustering analysis and CFA supported the 3-factor structure of the original scale, and all items, except for the item "absence of antisocial or violent", showed good psychometric characteristics. The correlated coefficients between FROGS and mini-FROGS with the GAF were excellent (FROGS: r = 0.74, p＜0.01; mini-FROGS: r = 0.65, p＜0.01). The retest showed that the scale had good stability and validity over time (ICC = 0.856; 95% CI = 0.701∼0.941). Both mini-FROGS and FROGS had good sensitivity and specificity for the measurement of social function (mini-FROGS: ROC-AUC = 84.3% (76.9%-91.6%), and FROGS: ROC-AUC = 89.2% (83.0%-95.4%)), and there was no difference between the two versions of ROC-AUC (P = 0.154).

CONCLUSION

The results of our study showed that the Chinese version of FROGS and mini-FROGS had good psychometric properties for assessing the social function of people with schizophrenia in China. In particular, the mini-FROGS version was better used in the clinical setting because of its convenience and efficiency.

Cystic duct cancer: Should it be deemed as a type of gallbladder cancer?

BACKGROUND

According to the latest American Joint Committee on Cancer and Union for International Cancer Control manuals, cystic duct cancer (CC) is categorized as a type of gallbladder cancer (GC), which has the worst prognosis among all types of biliary cancers. We hypothesized that this categorization could be verified by using taxonomic methods.

AIM

To investigate the categorization of CC based on population-level data.

METHODS

Cases of biliary cancers were identified from the Surveillance, Epidemiology, and End Results 18 registries database. Together with routinely used statistical methods, three taxonomic methods, including Fisher’s discriminant, binary logistics and artificial neuron network (ANN) models, were used to clarify the categorizing problem of CC.

RESULTS

The T staging system of perihilar cholangiocarcinoma [a type of extrahepatic cholangiocarcinoma (EC)] better discriminated CC prognosis than that of GC. After adjusting other covariates, the hazard ratio of CC tended to be closer to that of EC, although not reaching statistical significance. To differentiate EC from GC, three taxonomic models were built and all showed good accuracies. The ANN model had an area under the receiver operating characteristic curve of 0.902. Using the three models, the majority (75.0%-77.8%) of CC cases were categorized as EC.

CONCLUSION

Our study suggested that CC should be categorized as a type of EC, not GC. Aggressive surgical attitude might be considered in CC cases, to see whether long-term prognosis could be immensely improved like the situation in EC.

Polygraph Accuracy of Control Question Test in Criminal Cases

Objective To explore polygraph accuracy of Control Question Test （CQT）and whether it could be influenced by examinee's education level and type of violation of law. Methods Real cases of CQT （n=104） and the data from MAO （n=296） were collected. The polygraph accuracy of CQT was calculated. Variance analysis on three groups of different education levels was used to compare their age, and then the chi-square test was employed to compare polygraph accuracy among the groups. Independent sample t test was used to compare the age of subjects in the two groups of different types of violation of law, and then chi-square test was used to compare the true positive rate and true negative rate of lie detection after integration. Results In CQT lie detection of criminal cases, the true positive rate was 87.00%, the false negative rate was 13.00%, the true negative rate was 82.20%, and the false positive rate was 17.80%. There was no statistical significance in the differences between the true positive rate and the true negative rate （P>0.05）. In CQT lie detection of the groups of different education levels, there was no statistical significance in the differences between the true positive rates （P>0.05） while the differences between the true negative rates had statistical significance （P<0.05）. There was no statistical significance in the differences of both the true positive rates and the true negative rates between the violent violation of law and non-violent violation of law （P>0.05）. Conclusion There is no significant difference between the efficiency of CQT lie detection of identifying criminals and excluding innocents. However, a comparatively high false positive rate and false negative rate still exist. The efficiency of CQT lie detection identifying criminals may not influenced by the examinee's education level and type of violation of law, but its efficiency of excluding innocents may be influenced by the examinee's education level.

[Oral melphalan plus high-dose dexamethasone as first-line therapy for patients with primary light chain amyloidosis]

目的

探讨口服美法仑联合大剂量地塞米松（MDex）方案一线治疗原发性轻链型淀粉样变（pAL）的疗效。

方法

收集2009年1月至2017年7月接受MDex方案治疗的76例初治pAL患者临床资料，对其疗效及生存进行回顾性分析。

结果

①76例患者中，男47例，女29例，中位年龄为56（20~74）岁。66例患者可进行梅奥2004分期（1、2、3期者分别为21、32、13例），65例（85.53%）患者存在≥2个器官受累。中位疗程数为5（1~21）个。②在可评价疗效的60例患者中，总体血液学缓解率为48.33%（29/60），完全缓解率和非常好的部分缓解率均为20.00%（12/60），获得最佳血液学缓解的中位时间为5（1~15）个月；总体器官缓解率为36.67%（22/60）。③生存患者的中位随访时间为23（1~113）个月，中位无进展生存（PFS）及总生存（OS）时间及分别为34、43个月。治疗3个月后仍存活患者的中位PFS和OS时间分别为46、65个月。④梅奥2004分期3期和1~2期患者的中位OS时间分别为5、65个月，差异有统计学意义（P=0.001）。

结论

MDex方案是pAL早期患者一种有效的治疗手段，但不适用于心脏受累的晚期患者。

[Study of de novo point mutations in known genes among patients with unexplained intellectual disability or developmental delay]

Objective: To analyze the de novo point mutations in known genes among patients with unexplained intellectual disability (ID) or developmental retardation (DD). Methods: A total of 120 outpatients with ID or DD were recruited in the Department of Neurology, Affiliated Children's Hospital of Capital Institute of Pediatrics between September 2015 and April 2017. Target gene sequencing was used to screen the candidate gene. The sequencing data were analyzed by a variety of bioinformatics software. Combining with the phenotypes of the patients, the candidate genetic/genomic variants were identified from next-generation sequencing data. The final pathogenicity of the genetic/genomic variants were interpreted according to the guideline of the American College of Medical Genetics and Genomics (ACMG) for variants after segregation analysis in the parents and necessary family members by Sanger sequencing. The comprehensive physiological function and signaling pathways of 20 disease genes with de novo point mutation discovery was also studied. Results: Among the 120 patients, 23 patients were found to carry clear pathological changes, and the incidence of de novo point variation was 19.2%. The patients included 12 males and 11 females, with an age of 2 months to 6-year-6-month. Five patients were diagnosed with early onset of epileptic encephalopathy. Seven had mental retardation type 5, 6, 8, 19, 20, 22, 39, respectively. Weill-Marchesani syndrome type 2 was found in one case, Wiedemann-Steiner syndrome in one case, Coffin-Siris syndrome in two cases, Rubinstein-Taybi syndrome in one case, GLUT1 deficiency syndrome in one case, Rett syndrome in one case, cardio-facio-cutaneous syndrome 3 in one case, neurodegeneration with brain iron accumulation in one case, corpus callosum local dysplasia in one case, and congenital fibrosis of the extra-ocular muscles in one case. A total of 20 novel mutations were reported in this study. No somatic mutation was found in the samples of 6 patients with mutation and their parents' peripheral blood DNA samples by amplicon-based deep sequencing. This study found that the main disease genes were involved in chromatin remodeling, transcriptional regulation, autophagy body assembly, MAPK signal pathway, DNA methylation, potassium, sodium ion transport, cell skeleton assembly and skeletal muscle development. These genes were significantly enriched in the following biological processes: Ras signaling pathways, transcription factor binding and cancer related signaling pathway. Conclusions: The etiology of children affected with intellectual disability or developmental delay is complex. Harmful de novo point mutation plays an important role in these diseases. Targeted exome/genome sequencing based on the core family is helpful for the molecular diagnosis of patients and the discovery of more genes.

[Impact of KIT D816 mutation on salvage therapy in relapsed acute myeloid leukemia with t(8;21) translocation]

Objective: To evaluate the impact of KIT D816 mutation on the salvage therapy in relapsed acute myeloid leukemia (AML) with t(8;21) translocation. Method: The characteristics of the first relapsed AML with t(8;21) translocation from 10 hospitals were retrospectively collected, complete remission (CR(2)) rate after one course salvage chemotherapy and the relationship between KIT mutation and CR(2) rate was analyzed. Results: 68 cases were enrolled in this study, and 30 cases (44.1%) achieved CR(2). All patients received KIT mutation detection, and KIT D816 mutation was identified in 26 cases. The KIT D816 positive group had significantly lower CR(2) compared with non-KIT D816 group (23.1% vs 57.1%, χ(2)=7.559, P=0.006), and patients with longer CR(1) duration achieved significantly higher CR(2) than those with CR(1) duration less than 12 months (74.1% vs 31.9%, χ(2)=9.192, P=0.002). KIT D816 mutation was tightly related to shorter CR(1) duration. No significant difference of 2 years post relapse survival was observed between KIT D816 mutation and non-KIT D816 mutation group. Conclusion: KIT D816 mutation at diagnosis was an adverse factor on the salvage therapy in relapsed AML with t(8;21) translocation, significantly related to shorter CR1 duration, and can be used for prediction of salvage therapy response. KIT D816 mutation could guide the decision-making of salvage therapy in relapsed AML with t(8;21) translocation.

Associations between hsa-miR-603 polymorphism, lifestyle-related factors and colorectal cancer risk

BACKGROUND

Accumulated studies have suggested that single nucleotide polymorphisms (SNPs) in microRNAs are associated with risk of colorectal cancer (CRC).

OBJECTIVE

We tested our hypothesis that rs11014002 in hsa-miR-603 may be associated with CRC risk with a crosstalk of life-related factors.

METHODS

We conducted a case-control study which included 102 CRC patients and 204 matched cancer-free controls in Xiaoshan County.

RESULTS

We observed that subjects with rs11014002 CT/TT genotype had an increased susceptibility for CRC (CT vs. CC: odds ratio (OR)=2.352, 95% confidence interval (CI): 1.142-4.840, P=0.020; CT+TT vs. CC: OR=2.031, 95% CI: 1.063-3.883, P=0.032). After stratification by lifestyle-related factors, similar results were found among nonsmokers (CT vs. CC: OR=2.753, 95% CI: 1.085-6.983, P=0.033; CT+TT vs. CC: OR=2.971, 95% CI: 1.188-7.435, P=0.020) and non-alcohol drinkers (CT+TT vs. CC: OR=3.279, 95% CI: 1.071-10.033, P=0.037).

CONCLUSIONS

Our data suggest that hsa-miR-603 may be involved in colorectal tumorigenesis, and the genetic polymorphism in hsa-miR-603 is associated with CRC susceptibility.

rs12904 polymorphism in the 3'UTR of EFNA1 is associated with colorectal cancer susceptibility in a Chinese population

Accumulated evidence has indicated that Ephrin A1 (EFNA1) is associated with angiogenesis and tumorigenesis in various types of malignancies, including colorectal cancer (CRC). In the current study, we performed an online search using the public microarray database to investigate whether EFNA1 expression might be altered in CRC tissues. We then conducted a case-control study including 306 subjects (102 cases and 204 well-matched controls) in Xiaoshan County to assess any association between genetic polymorphisms in EFNA1 and CRC susceptibility. Searches in the Oncomine expression profiling database revealed EFNA1 to be overexpressed in CRC tissue compared with adjacent normal tissue. The rs12904 G-A variant located in the 3' untranslated region (UTR) of EFNA1 was observed to be associated with CRC susceptibility. Compared with the AA homozygous genotype, those carrying GA genotype had a decreased risk of developing CRC (odds ratio (OR) =0.469, 95% confidence interval (CI): 0.225-0.977, and P =0.043). The association was stronger among smokers and tea drinkers, however, no statistical evidence of interaction between rs12904 polymorphism and smoking or tea drinking on CRC risk was found. Our results suggest that EFNA1 is involved in colorectal tumorigenesis, and rs12904 A>G polymorphism in the 3' UTR of EFNA1 is associated with CRC susceptibility. Larger studies and further mechanistic investigations are warranted to confirm our findings.

A genetic variant in MiR-146a modifies digestive system cancer risk: a meta-analysis

MicroRNAs (miRNAs) negatively regulate gene expression and act as tumor suppressors or oncogenes in oncogenesis. The association between a single nucleotide polymorphism (SNP) in miR-146a rs2910164 and susceptibility to digestive system cancers was inconsistent in previous studies. In this study, we conducted a literature search of PubMed to identify all relevant studies published before August 31, 2013. A total of 21 independent case-control studies were included in this updated meta-analysis with 9,558 cases and 10,614 controls. We found that the miR-146a rs2910164 polymorphism was significantly associated with decreased risk of digestive system cancers in an allele model (OR=0.90, 95%CI 0.87-0.94), homozygote model (OR=0.84, 95%CI 0.77-0.91), dominant model (OR=0.90, 95%CI 0.84-0.96), and recessive model (OR=0.85, 95%CI 0.79-0.91), while in a heterozygous model (OR = 0.99, 95% CI 0.89-1.11) the association showed marginal significance. Subgroup analysis by cancer site revealed decreased risk in colorectal cancer above allele model (OR=0.90, 95%CI 0.83- 0.97) and homozygote model (OR=0.85, 95%CI 0.72-1.00). Similarly, decreased cancer risk was observed when compared with allele model (OR=0.87, 95%CI 0.81-0.93) and recessive model (OR=0.81, 95%CI 0.72-0.90) in gastric cancer. When stratified by ethnicity, genotyping methods and quality score, decreased cancer risks were also observed. This current meta-analysis indicated that miR-146a rs2910164 polymorphism may decrease the susceptibility to digestive system cancers, especially in Asian populations.

CpG oligodeoxynucleotide inhibits HBV replication in a hydrodynamic injection murine model

BACKGROUND

Chronic HBV infection is a significant public health problem and one major cause of liver cirrhosis and hepatocellular carcinoma (HCC). HBV impairs the host immune system and results in immunotolerance, which is a major obstacle to HBV therapy. CpG oligodeoxynucleotide (ODN) is a strong immunostimulant which activates the innate immune response rapidly and has been shown to be an efficient therapy agent in viral infection treatment. Here, we report the anti-HBV activity of CpG-1826 in a hydrodynamic injection murine model.

METHODS

CpG-1826 was administrated intraperitoneally every other day in HBV carrier mice established by tail vein hydrodynamic injection of HBV plasmids. The serum concentrations of HBV surface antigen (HBsAg), HBV e antigen (HBeAg), HBV surface antibody (HBsAb), HBV core antibody (HBcAb), interferon-α (IFN-α) and interferon-γ (IFN-γ) were measured by enzyme-linked immunosorbent assay (ELISA). The activities of alanine aminotransferase (ALT) were determined by ALT kit using a Spectramax Plus spectrophotometer. Hepatic HBV DNA was quantified by quantitative real-time PCR. The expression of HBV core antigen (HBcAg) in liver was detected by immunohistochemistry. Drug toxicity of CpG-1826 was evaluated by body weighting and liver histopathology confirmation.

RESULTS

CpG-1826 administration inhibited HBV replication efficiently with significant reduction of serum HBsAg and HBeAg, hepatic HBcAg and HBV DNA levels. The serum levels of IFN-α, IFN-γ and HBsAb increased but the HBcAb level declined in the CpG-1826 group compared to CpG-1982 and PBS control groups. Results of ALT activity indicated no significant difference among CpG-1826 group, CpG-1982 and PBS control groups. Body weighting and histopathology examination showed no obvious toxicity.

CONCLUSIONS

Given the stimulation activity of a host immune system, CpG ODN is a promising strategy for HBV therapy with more relevant research needed.

Endophytic fungal metabolite fumigaclavine C causes relaxation of isolated rat aortic rings

Two indole alkaloids were isolated from the culture of Aspergillus fumigatus (strain No. CY018), an endophytic fungus harboring inside the elder leaf of Cynodon dactylon. These two chemicals were identified as fumigaclavine C and fumitremorgin C. In screening the bioactivity of these two indole alkaloids, their vasorelaxant effects on isolated rat thoracic aortic rings were observed. The results showed that fumigaclavine C exhibited potent concentration-dependent vasorelaxant actions in isolated rat aortic rings pre-contracted by high K+ or phenylephrine (with EC50 values of 5.62 micromol/L and 1.58 micromol/L, respectively) whereas fumitremorgin C displayed a weaker vasorelaxation. A detailed investigation was therefore performed with fumigaclavine C. The vasorelaxing action of fumigaclavine C is independent of the presence of endothelium, suggesting its effect of vasorelaxation was not related to endothelial mediators. Blockage of L-type voltage-dependent calcium channels, activation of ATP-sensitive potassium channels and inhibition of Ca2+ release from intracellular Ca2+ stores may be involved in fumigaclavine C induced relaxation of rat isolated aortic rings. These results demonstrate that fumigaclavine C from the endophytic fungus has a potential capacity in vascular protection and thus may have therapeutic use in protection against cardiovascular disease.

The Impact of Pretransplant Cytomegalovirus Infection on Acute Renal Allograft Rejection

BACKGROUND

The role of cytomegalovirus (CMV) infection in renal allograft rejection remains controversial; moreover, there are few studies on pretransplant infections. This study sought to investigate whether pretransplant CMV infections had negative effects on acute rejection episodes (ARE) and to evaluate the effect of preemptive treatment.

METHODS

This retrospective single-center study of 416 transplant recipients from October 1, 2000 to September 1, 2003 had CMV infections diagnosed by CMV antigenemia tests. The incidences of ARE were compared between CMV-infected and noninfected groups. Risk factors for ARE were analyzed. Based on preemptive treatment, pretransplant CMV-infected recipients were divided into ganciclovir-treated and nontreated groups and the incidence of ARE was compared between the two groups.

RESULTS

One hundred eighty four recipients had CMV infections pretransplant; the infection rate was 44.2%. Fifty five recipients had ARE among the pretransplant CMV-positive group, which was significantly higher than that in the noninfected group (29.9% vs 19.5%, P = .014). But the rejection subgroups and renal function recovery had no significant differences. While the presence of pretransplant infection was an independent predictor of ARE (RR = 1.807), severity showed no significant impact on ARE. Among 184 pretransplant CMV infection recipients, the incidences of ARE were 14.3% and 18.0% in ganciclovir-treated versus nontreated patients, respectively (P = .650).

CONCLUSIONS

Pretransplant CMV-positive recipients were at greater risk of ARE. Pretransplant CMV infection was an independent risk factor for ARE. Preemptive antiviral treatment did not show protective effects against ARE related to CMV infection-mediated immunological injuries.

Inhibitory effects of flavonoids from Hypericum perforatum on nitric oxide synthase

The inhibitory effects of six flavonoids from Hypericum perforatum were assessed spectrophotometrically using nitric oxide synthase (NOS) in blood and cerebral homogenate of rats. Of the assayed compounds, quercetin and hyperoside showed concentration-dependent enzyme inhibitory actions. The IC50 values of quercetin for inhibiting NOS in rat cerebral homogenate and blood were 63.06 and 57.54 microM, and those of hyperoside 56.23 and 158.49 microM, respectively. The competitive patterns were discerned with the inhibition of the two flavonoids on NOS in serum and cerebral homogenate (except a mixed type inhibition was observed with quercetin in inhibiting cerebral NOS). Furthermore, similar inhibitions were found for quercetin upon NOS in cerebral homogenate and blood. However, a stronger inhibitory effect of hyperoside on the enzyme was discerned in cerebrum than in blood. These results suggested that the galactose moiety in hyperoside may be associated with the selectivity of the NOS inhibition.