[Molecular epidemiological characterization of hypervirulent carbapenem-resistant Klebsiella pneumoniae in a hospital in Henan Province from 2020 to 2022]

Objective: The study investigated the clinical distribution, antimicrobial resistance and epidemiologic characteristics of hypervirulent Carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) in a hospital in Henan Province to provide a scientific basis for antibiotic use and nosocomial infection prevention and control. Methods: A retrospective analysis of the clinical data from the cases was carried out in this study. Clinical data of patients infected with the CRKP strain isolated from the clinical microbiology laboratory of Henan Provincial Hospital of Traditional Chinese Medicine from January 2020 to December 2022 were retrospectively analyzed. A string test, virulence gene screening, serum killing, and a G. mellonella infection model were used to screen hv-CRKP isolates. The clinical characteristics of hv-CRKP and the drug resistance rate of hv-CRKP to twenty-five antibiotics were analyzed using WHONET 5.6. Carbapenemase phenotypic characterization of the hv-CRKP was performed by colloidal gold immunochromatographic assay, and Carbapenemase genotyping, multi-locus sequence typing (MLST) and capsular serotyping of hv-CRKP isolates were performed by PCR and Sanger sequencing. Results: A total of non-duplicate 264 CRKP clinical isolates were detected in the hospital from 2020 to 2022, and 23 hv-CRKP isolates were detected, so the corresponding detection rate of hv-CRKP was 8.71% (23/264). The hv-CRKP isolates in this study were mainly from the intensive care unit (10/23) and neurosurgery department (8/23), and the main sources of hv-CRKP isolates were sputum (10/23) and bronchoalveolar lavage fluid (6/23). The hv-CRKP isolates in this study were highly resistant to β-lactam antibiotics, fluoroquinolones and aminoglycosides, and were only susceptible to colistin, tigecycline and ceftazidime/avibactam. The detection rate of the blaKPC-2 among 23 hv-CRKP isolates was 91.30% (21/23) and none of the class B and class D carbapenemases were detected. Results of MLST and capsular serotypes showed that ST11 type hv-CRKP was the dominant strain in the hospital, accounting for 56.52% (13/23), and K64 (9/13) and KL47 (4/13) were the major capsular serotypes. Conclusion: The hv-CRKP isolates from the hospital are mainly from lower respiratory tract specimens from patients admitted to the intensive care department and the drug resistance is relatively severe. The predominant strains with certain polymorphisms are mainly composed of the KPC-2-producing ST11-K64 and ST11-KL47 hv-CRKP isolates in the hospital.

[Constructions and advances of animal models of Pseudomonas aeruginosa infection]

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogenic bacterium with complex pathogenesis and drug resistance mechanisms. It has high morbidity and mortality and can cause acute and chronic infections in immunocompromised individuals, with lung infections, wound infections, and bloodstream infections being the most common. The animal infection model of P. aeruginosa is of great value for in-depth research on the pathogenicity, drug resistance, and therapeutic measures of P. aeruginosa by simulating the pathways of human bacterial infections. This article firstly summarizes the selection, anesthesia, and disposal of experimental animals in the construction of animal models of P. aeruginosa infection, and then reviews the methods of construction, model evaluation, and applications of animal models of P. aeruginosa pulmonary infection, wound infection, and bloodstream infection, in order to provide a reference for scientific research related to P. aeruginosa infectious diseases.

[Analysis of 7 cases of pediatric acute myeloid leukemia with DEK-NUP214 fusion gene]

Objective: To investigate the clinical features, treatment regime, and outcome of pediatric acute myeloid leukemia (AML) with DEK-NUP214 fusion gene. Methods: The clinical data, genetic and molecular results, treatment process and survival status of 7 cases of DEK-NUP214 fusion gene positive AML children admitted to the Pediatric Blood Diseases Center of Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences from May 2015 to February 2022 were analyzed retrospectively. Results: DEK-NUP214 fusion gene positive AML accounted for 1.02% (7/683) of pediatric AML diagnosed in the same period, with 4 males and 3 females. The age of disease onset was 8.2 (7.5, 9.5) years. The blast percentage in bone marrow was 0.275 (0.225, 0.480), and 6 cases were M5 by FAB classification. Pathological hematopoiesis was observed in all cases except for one whose bone marrow morphology was unknown. Three cases carried FLT3-ITD mutations, 4 cases carried NRAS mutations, and 2 cases carried KRAS mutations. After diagnosis, 4 cases received IAE induction regimen (idarubicin, cytarabine and etoposide), 1 case received MAE induction regimen (mitoxantrone, cytarabine and etoposide), 1 case received DAH induction regimen (daunorubicin, cytarabine and homoharringtonine) and 1 case received DAE induction regimen (daunorubicin, cytarabine and etoposide). Complete remission was achieved in 3 cases after one course of induction. Four cases who did not achieved complete remission received CAG (aclarubicin, cytarabine and granulocyte colony-stimulating factor), IAH (idarubicin, cytarabine and homoharringtonine), CAG combined with cladribine, and HAG (homoharringtonine, cytarabine and granulocyte colony-stimulating factor) combined with cladribine reinduction therapy, respectively, all 4 cases reached complete remission. Six patients received hematopoietic stem cell transplantation (HSCT) after 1-2 sessions of intensive consolidation treatment, except that one case was lost to follow-up after complete remission. The time from diagnosis to HSCT was 143 (121, 174) days. Before HSCT, one case was positive for flow cytometry minimal residual disease and 3 cases were positive for DEK-NUP214 fusion gene. Three cases accepted haploid donors, 2 cases accepted unrelated cord blood donors, and 1 case accepted matched sibling donor. The follow-up time was 20.4 (12.9, 53.1) months, the overall survival and event free survival rates were all 100%. Conclusions: Pediatric AML with DEK-NUP214 fusion gene is a unique and rare subtype, often diagnosed in relatively older children. The disease is characterized with a low blast percentage in bone marrow, significant pathological hematopoiesis and a high mutation rate in FLT3-ITD and RAS genes. Low remission rate by chemotherapy only and very high recurrence rate indicate its high malignancy and poor prognosis. Early HSCT after the first complete remission can improve its prognosis.

[Efficacy of transcatheter pulmonary valve perforation in neonates with pulmonary atresia with intact ventricular septum]

Objective: To explore the efficacy and safety of transcatheter pulmonary valve perforation in the treatment of neonatal pulmonary atresia with intact ventricular septum (PA-IVS). Methods: The clinical data on surgical treatment and follow-up in 16 patients with PA-IVS who underwent transcatheter pulmonary valve perforation in Women and Children's Hospital, Qingdao University from October 2018 to October 2021 were analyzed retrospectively. The right ventricular systolic pressure and percutaneous oxygen saturation (SpO₂) were compared before and after operation. In addition, the SpO₂ and echocardiographic data at preoperative and the last follow-up were compared. Comparisons between groups were performed using paired-samples t test. Results: Among the 16 patients (10 males and 6 females) with the age at operation of 19 (14, 26) days, 12 cases underwent transcatheter pulmonary valve perforation successfully, 2 cases were transferred to surgery department for open-heart pulmonary valvulotomy, and the remaining 2 cases were transmitted to surgery department for transthoracic pulmonary valve perforation. The age at operation of the 12 patients who underwent transcatheter pulmonary valve perforation was 18 (14, 27) days, and the weight was (3.6±0.4) kg. The immediate postoperative right ventricular systolic pressure decreased significantly ((57±16) vs. (95±19) mmHg (1 mmHg=0.133 kPa), t=7.49, P<0.001), and the postoperative SpO₂ was improved effectively (0.90±0.48 vs.0.75±0.09, t=-5.61, P<0.001). The follow-up time was 22 (7, 33) months for 12 patients who underwent transcatheter pulmonary valve perforation successfully. At the last follow-up, the ratio of right to left ventricular transverse diameter was significantly higher than that before operative (0.55±0.05 vs. 0.45±0.05, t=-3.27,P=0.007). Furthermore, the Z-scores of pulmonary valvular diameter (-0.78±0.23 vs. -1.73±0.56, t=-8.52, P<0.001) and the tricuspid valvular diameter (-0.52±0.12 vs. -1.46±0.38, t=-10.40, P<0.001) were all significantly higher than preoperative data. At last, all the patients achieved biventricular circulation without death or major complications. Conclusion: Transcatheter pulmonary valve perforation is a safe and effective therapy for neonatal PA-IVS, and its curative effect has been confirmed by the medium follow-up data.

Developing a New qFIBS Model Assessing Histological Features in Pediatric Patients With Non-alcoholic Steatohepatitis

Background

The evolution of pediatric non-alcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH) is associated with unique histological features. Pathological evaluation of liver specimen is often hindered by observer variability and diagnostic consensus is not always attainable. We investigated whether the qFIBS technique derived from adult NASH could be applied to pediatric NASH.

Materials and Methods

102 pediatric patients (<18 years old) with liver biopsy-proven NASH were included. The liver biopsies were serially sectioned for hematoxylin-eosin and Masson trichrome staining for histological scoring, and for second harmonic generation (SHG) imaging. qFIBS-automated measure of fibrosis, inflammation, hepatocyte ballooning, and steatosis was estabilshed by using the NASH CRN scoring system as the reference standard.

Results

qFIBS showed the best correlation with steatosis (r = 0.84, P < 0.001); with ability to distinguish different grades of steatosis (AUROCs 0.90 and 0.98, sensitivity 0.71 and 0.93, and specificity 0.90 and 0.90). qFIBS correlation with fibrosis (r = 0.72, P < 0.001) was good with high AUROC values [qFibrosis (AUC) > 0.85 (0.85–0.95)] and ability to distinguish different stages of fibrosis. qFIBS showed weak correlation with ballooning (r = 0.38, P = 0.028) and inflammation (r = 0.46, P = 0.005); however, it could distinguish different grades of ballooning (AUROCs 0.73, sensitivity 0.36, and specificity 0.92) and inflammation (AUROCs 0.77, sensitivity 0.83, and specificity 0.53).

Conclusion

It was demonstrated that when qFIBS derived from adult NASH was performed on pediatric NASH, it could best distinguish the various histological grades of steatosis and fibrosis.

[Research progress on virulence factors of hypervirulent Klebsiella pneumoniae]

Hypervirulent Klebsiella pneumoniae, short for hvKP, is a hypervirulent variant of classical Klebsiella pneumoniae, which accounts for serious infection in healthy people, exhibits strong pathogenicity, high mortality and poor prognosis. At present, hvkp is of high prevalence all over the world, and the infection rate shows a continuous upward trend, which brings great challenges to public health security and clinical treatment. This paper summarized the research progress on virulence factors of hvkp, such as capsular polysaccharides, siderophore, lipopolysaccharide, adhesins and recently discovered Type Ⅵ secreting system, and aimed to deepen the understanding and recognition of hvKP.

[The hematological diversity of human parvovirus B19 infection after allo-hematopoietic stem cell transplantation in pediatric patients]

目的

探讨异基因造血干细胞移植（allo-HSCT）患儿造血重建后人类细小病毒B19（HPV-B19）感染的血液学表现。

方法

对9例allo-HSCT后合并HPV-B19感染的患儿进行回顾性分析。

结果

9例患儿占同期接受allo-HSCT患儿的8.04％（9/112），男8例，女1例，中位年龄9（3～13）岁，均采取清髓性预处理方案。HPV-B19感染中位时间为移植后61（36～114）d。allo-HSCT并发HPV-B19感染患儿血液学表现具有异质性，9例患儿以血红蛋白伴网织红细胞下降为主要特点，7 d内网织红细胞比例、绝对值下降幅度中位数分别为90.4％（24.7％～98.7％）、90.7％（18.6％～99.0％）。除常见红系造血停滞表现外，allo-HSCT后合并HPV-B19感染的患儿还具有非红系的血象及骨髓变化：5例患儿外周血出现中性粒细胞下降，但骨髓涂片未见粒系增生受抑；6例患儿骨髓涂片查见巨核系增生减低，其中5例患儿外周血血小板下降。同时，allo-HSCT造血重建后合并HPV-B19感染的患儿骨髓红系受抑并非必要表现，9例患儿虽然均出现血红蛋白下降，但仅5例患儿骨髓红系增生减低。

结论

血液病患儿allo-HSCT造血重建后合并HPV-B19感染的血液学表现具有异质性，血红蛋白伴网织红细胞下降对HPV-B19感染早期诊断可能具有重要意义。

[Clinical characteristics of patients with odontogenic sinusitis underwent endoscopic sinus surgery]

Objective: To analyze the clinical features of patients with odontogenic sinusitis (OS) treated by endoscopic sinus surgery (ESS). Methods: A retrospective investigation was carried out in our 27 (16 males and 11 females) cases with OS aged (49.74±14.42) years old. Subjects were hospitalized between January 2018 and November 2020 from Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital. The medical history, symptoms, result of nasal endoscopy and paranasal sinus computed tomography (CT) were analyzed statistically by SPSS 19.0. Results: OS mainly occured on unilateral sinuses, with a duration of (8.56±11.79) months. Seventy point four percent (19/27) of the patients had a course within six-month, only 11% was over 12 months (3/27). Symptoms mostly showed as nasal obstruction (88.9%; 24/27), runny nose (81.5%; 22/27), nasal stinks (16/19) and postnasal drip (10/10). Sixty-three percent (17/27) of the OS patients had a dental history. Nasal endoscopic examination revealed a swelling of the ostiomeatal complex (77.8%; 21/27), medial wall interhal displacement of maxillary sinus (55.6%; 15/27), white emulsion-like purulent secretion in the middle meatus (70.4%; 19/27) and nasal polyps (59.3%; 16/27). Etiology of OS included implant-related problems (14.8%; 4/27) and periodontal disease (85.2%; 23/27). Conclusions: OS is usually unilateral sinusitis with a short history. Its clinical features show nasal stinks, white emulsion-like purulent secretion in the middle meatus and imaging findings of unilateral maxillary sinusitis with tooth-related lesions.

[Analysis of bloodstream infections in children with acute myeloid leukemia during induction chemotherapies]

Objective: To explore the clinical features of bloodstream infections (BSI) in children with acute myeloid leukemia (AML) during the first induction chemotherapy. Methods: The clinical data, pathogen of BSI, antibiotic susceptibility in vitro, complications and prognosis of 204 newly diagnosed AML children admitted to Blood Diseases Hospital, Chinese Academy of Medical Sciences from August 2009 to December 2015 were analyzed retrospectively. χ² test was used for the comparison between groups and Logistic regression was used for BSI risk factor analysis. Results: Among 204 patients, 116 were males and 88 were females. The age was 8 (ranged from 1 to 14) years. Among them, 170 patients received MAE chemotherapies (etoposide, mitoxantrone and cytarabine) and 25 received IAE chemotherapies (etoposide, idarubicin and cytarabine). The other 9 patients used granulocyte colony stimulating factor (G-CSF)-priming regimen (aclacinomycin or homoharringtonine, cytarabine and G-CSF) for induction treatments. A total of 28 patients experienced BSI and the incidence rate was 13.7% (28/204), 26 of them developed BSI once and 2 patients developed twice. Gram-positive bacteria were predominant pathogens accounting for 53.3% (16/30) while gram-negative bacteria accounting for 40.0% (12/30) and fungal accounted for 6.7% (2/30). The most common detected pathogens were Coagulase negative Staphylococcus (CoNS, 26.7% (8/30)), followed by Streptococcus spp. (13.3% (4/30)) and Escherichia coli (13.3% (4/30)). Among Gram-negative bacteria (GNB), 3 cases showed carbapenem resistance and 2 cases were Stenotrophomonas maltophilia. BSI-related mortality was 28.6% (8/28). Infections caused by drug-resistant GNB or fungi resulted in 6 fatal cases. The incidence rate of BSI in group with severe neutropenia was higher than in group without it (16.6% (25/151) vs. 5.7% (3/53), χ²=3.933, P=0.047). Multivariable analysis showed severe neutropenia at the onset of fever was independent risk factor of BSI (OR=4.258,95%CI 1.097-16.524,P=0.036). Conclusions: During the first induction chemotherapy courses, Gram-positive bacteria cause most of the BSI. Drug-resistant bacteria related infection often result in fatal outcomes. Severe neutropenia is a significant risk factor.

[Familial platelet disorder with predisposition to myeloid leukemia (FPD/AML): a case report and literature review]

目的

探讨RUNX1胚系突变导致的家族性血小板疾病并急性髓系白血病倾向（FPD/AML）患儿及其家族成员的临床特点及基因突变情况。

方法

对2019年10月中国医学科学院血液病医院儿童血液诊疗中心收治的1例FPD/AML患儿及部分家族成员的临床资料及基因突变结果进行分析。并以“RUNX1胚系突变”“家族性血小板疾病并急性髓系白血病倾向”“RUNX1 germline mutation”“FPD/AML”为检索词，检索建库至2020年9月中文数据库（中国知网数据库、万方数据库及维普数据库）及PubMed数据库进行文献复习。

结果

患儿为5岁男孩，因发现血小板减少3年入院。体格检查提示存在皮肤出血点，其他无明显异常。辅助检查：外周血常规示WBC 6.38×10⁹/L，HGB 113 g/L，PLT 54×10⁹/L，中性粒细胞绝对计数4.03×10⁹/L，血小板平均体积（MPV）9.1 fl。骨髓涂片提示巨核系发育异常。涂片免疫CD42b及CD41酶标提示存在小巨核细胞。基因检测提示RUNX1（exon3: c.520delC:p.R174Efs*10, NM_001001890）的移码突变，经口腔上皮细胞验证为胚系突变。家族史中共有5名家族成员存在血液系统疾病并相继死亡。患儿母亲及外祖父先后进行了与血液肿瘤疾病相关的137个基因热点区域的基因检测，均检测到与患儿相同位点的RUNX1移码突变，但是三人的临床症状十分不同。文献检索共检索到相关英文文献37篇，报道了70多个FPD/AML家族，未检索到相关中文文献。

结论

RUNX1胚系突变是导致FPD/AML的病因，进展为髓系恶性肿瘤的风险极高，携带相同突变的家族成员可能表现出非常不同的临床症状和严重程度。

[Efficacy and prognostic factors of the chemotherapy regimen of CCLG-ALL-2008 on pediatric acute lymphoblastic leukemia with ETV6-RUNX1 rearrangement]

Objective: To evaluate the predictive role of ETV6-RUNX1 fusion gene in protocol CCLG-ALL-2008 as well as identify the prognostic factors that influence the outcome of ALL with ETV6-RUNX1 fusion gene. Methods: One hundred and seventy-eight patients newly diagnosed with pediatric acute lymphoblastic leukemia with ETV6-RUNX1 rearrangement from April 2008 to April 2015 were enrolled in CCLG-ALL-2008. The follow up period ended in July 2018; we performed retrospective analyses of their data to determine the efficacy of the regimen and the prognostic factors. Results: The median age of the study population (178 pediatric patients) , including 100 boys and 78 girls was 4 (1-13) y, and the median white blood cell count at diagnosis was 9.46 (1.25-239.83) ×10(9)/L. Three patients died, and 1 was lost to follow up by the end of the first induction chemotherapy, resulting in an induced remission rate of 97.8% (174/178) . The cumulative incidence of relapse was 15.9% with a median follow up of 73.5 mon. Total 83.3% of the relapse cases were those of isolated bone marrow relapse, while 79.2% of the cases were those of late relapse. The median interval time between relapse and first complete remission was 35.5 mon (range, 1-62 months) . One of the 5 patients with early recurrence and 7 of the 19 with late recurrence cases survived. The 5-year-OS and 5-year-EFS of ETV6-RUNX1 positive children was (89.4±2.4) % and (82.1±6.9) %, respectively. The estimated 10-year-OS and 10-year-EFS of ETV6-RUNX1 positive children was (88.6±2.5) % and (77.3±4.0) %, respectively. The Kaplan-Meier method and Log-rank test were used to estimate and compare the survival. Univariate statistical analysis showed that poor prognostic factors that influenced survival included central nervous system state 2 at diagnosis, poor prednisone response, high risk, gene positivity after induction chemotherapy, as well as MRD positivity and gene positivity at the 12(th) week. In the multivariate analysis, only the central nervous system state 2 at diagnosis and MRD positivity at the 12(th) week were associated with the outcome. Conclusion: ETV6-RUNX1-positive ALL is a subgroup with a favorable prognosis as per the CCLG-ALL-2008 protocol. Patients with ETV6-RUNX1 should be given more intensive therapy, including hematopoietic stem cell transplantation when they are CNS2 at diagnosis or have high level of MRD at the 12(th) week after treatment.

[Characteristics of postviral olfactory disorder]

Objective: To explore the clinical characteristics of patients with olfactory dysfunction after upper respiratory tract infection. Methods: Through clinical specialist examination and imaging examination, 95 cases of patients with olfactory dysfunction after upper respiratory tract infection were confirmed, 58 cases in anosmia group and 37 cases in hyposmia group. All were performed by a subjective olfactometry (Sniffin'Sticks test) and a subjective taste function tests. The results were statistically analyzed by SPSS 17.0 software. Results: In 58 cases of anosmia group, 21 cases of male, 37 cases of female; Twenty-six cases of youth, 23 cases of middle age, 9 cases of old age; Twenty-seven cases occurs in spring, 11 cases in summer, 12 in autumn and 8 in winter. Among 37 cases of hyposmia group, 12 cases of male, 25 cases of female; Eighteen cases of youth, 16 cases of middle age, 3 cases of old age; Fourteen cases occurs in spring, 8 cases in summer, 7 in autumn and 8 in winter. There was no statistically significant difference in gender, age and the onset season between the two groups(χ²=0.142, P>0.05; χ²=1.124, P>0.05; χ²=1.335, P>0.05). In anosmia group, with 4 cases of ageusia, 22 cases of hypogeusia, 32 cases of normal taste; in hyposmia group, with 0 cases of ageusia, 10 cases of hypogeusia, 27 cases of normal taste. There were significant differences between the two groups with different types of taste disorder(Pearson correlation coefficient r=0.210, P<0.05), it was positive correlation. Conclusions: It is suggested that after the upper respiratory tract infection, the olfactory dysfunction is often accompanied by the sense of taste dysfunction, the more severe the damage of olfactory function, the degree of damage to the taste function is also increased. Olfactory impairment degree exhibited no relationship with gender, age or onset seasons.

Automated evaluation of liver fibrosis in thioacetamide, carbon tetrachloride, and bile duct ligation rodent models using second-harmonic generation/two-photon excited fluorescence microscopy

Animal models provide a useful platform for developing and testing new drugs to treat liver fibrosis. Accordingly, we developed a novel automated system to evaluate liver fibrosis in rodent models. This system uses second-harmonic generation (SHG)/two-photon excited fluorescence (TPEF) microscopy to assess a total of four mouse and rat models, using chemical treatment with either thioacetamide (TAA) or carbon tetrachloride (CCl₄), and a surgical method, bile duct ligation (BDL). The results obtained by the new technique were compared with that using Ishak fibrosis scores and two currently used quantitative methods for determining liver fibrosis: the collagen proportionate area (CPA) and measurement of hydroxyproline (HYP) content. We show that 11 shared morphological parameters faithfully recapitulate Ishak fibrosis scores in the models, with high area under the receiver operating characteristic (ROC) curve (AUC) performance. The AUC values of 11 shared parameters were greater than that of the CPA (TAA: 0.758-0.922 vs 0.752-0.908; BDL: 0.874-0.989 vs 0.678-0.966) in the TAA mice and BDL rat models and similar to that of the CPA in the TAA rat and CCl₄ mouse models. Similarly, based on the trends in these parameters at different time points, 9, 10, 7, and 2 model-specific parameters were selected for the TAA rats, TAA mice, CCl₄ mice, and BDL rats, respectively. These parameters identified differences among the time points in the four models, with high AUC accuracy, and the corresponding AUC values of these parameters were greater compared with those of the CPA in the TAA rat and mouse models (rats: 0.769-0.894 vs 0.64-0.799; mice: 0.87-0.93 vs 0.739-0.836) and similar to those of the CPA in the CCl₄ mouse and BDL rat models. Similarly, the AUC values of 11 shared parameters and model-specific parameters were greater than those of HYP in the TAA rats, TAA mice, and CCl₄ mouse models and were similar to those of HYP in the BDL rat models. The automated evaluation system, combined with 11 shared parameters and model-specific parameters, could specifically, accurately, and quantitatively stage liver fibrosis in animal models.

[Analysis of clinical characteristics and prognosis of non-severe aplastic anemia children with chromosomal abnormalities]

Objective: To analyze the clinical characteristics and prognosis of non-severe aplastic anemia (NSAA) with chromosomal abnormalities in children. Method: A retrospective analysis of 304 cases with NSAA with successful karyotyping from 2001 to 2014 in the Institute of Hematology & Blood Disease Hospital was carried out. The treatment response, condition of blood transfusion were analyzed using χ² test, the cumulative survival was estimated by the Kaplan-Meier method. Result: Out of 304 patients, 28 patients had chromosomal abnormalities with trisomy 8 (7 cases, 25.0%), abnormalities in chromosome 7 (5 cases, 17.9%), and other types (16 cases, 57.1%). There were no significant differences in the treatment response(40.9% (9/22)vs. 58.6%(119/203), χ²=2.539, P=0.111), the rate of getting rid of blood transfusion(54.5%(6/11) vs. 65.0%(39/60), χ²=6.455, P=0.086), five-year progression-free survival (49.2% vs.70.8%, χ²=0.849, P=0.357), and five-year cumulative survival (79.1% vs. 92.8%, χ²=0.330, P=0.556) between the patients with or without chromosomal abnormalities. There were significant differences in the rate of disease progression(41.7%(10/24) vs. 22.3%(48/215), χ²=4.394, P=0.045), the incidence of myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) (20.8%(5/24)vs. 0.9%(2/215), χ²=30.082, P=0.000)and the five-year cumulative incidence of MDS or AML(33.4% vs. 0.8%, χ²=17.798, P=0.000)between children with and without chromosomal abnormalities. Conclusion: The incidence of chromosomal abnormalities in children with NSAA is 9.2%. The clinical features and treatment response are similar, but children with chromosomal abnormalities have a poorer prognosis, and have higher risk of progressing to MDS or AML.

Predicting the aquatic toxicity mode of action using logistic regression and linear discriminant analysis

The paper highlights the use of the logistic regression (LR) method in the construction of acceptable statistically significant, robust and predictive models for the classification of chemicals according to their aquatic toxic modes of action. Essentials accounting for a reliable model were all considered carefully. The model predictors were selected by stepwise forward discriminant analysis (LDA) from a combined pool of experimental data and chemical structure-based descriptors calculated by the CODESSA and DRAGON software packages. Model predictive ability was validated both internally and externally. The applicability domain was checked by the leverage approach to verify prediction reliability. The obtained models are simple and easy to interpret. In general, LR performs much better than LDA and seems to be more attractive for the prediction of the more toxic compounds, i.e. compounds that exhibit excess toxicity versus non-polar narcotic compounds and more reactive compounds versus less reactive compounds. In addition, model fit and regression diagnostics was done through the influence plot which reflects the hat-values, studentized residuals, and Cook's distance statistics of each sample. Overdispersion was also checked for the LR model. The relationships between the descriptors and the aquatic toxic behaviour of compounds are also discussed.

Polymorphisms and DNA methylation level in the CpG site of the GHR1 gene associated with mRNA expression, growth traits and hormone level of half-smooth tongue sole (Cynoglossus semilaevis)

The objectives of the present study were to estimate the GHR1 gene mutations and methylation status of CpGs, and whether those mutations and methylation were involved in the regulation of GHR1 gene expression, hormone level and growth traits in half-smooth tongue sole (Cynoglossus semilaevis). Identification of single-nucleotide polymorphisms was performed on 43 male fish. Through polymerase chain reaction-single-strand conformation polymorphism and sequencing, two SNPs were found. SNP1 [c.G1357A (p.Val376Ile)] creating one CpG site located in exon 8 was named L1 locus, and SNP2 (c.G1479A) located in exon 9 was named L2 locus. Individuals were divided into three genotypes, AA, AG and GG according to L1 locus (GG genotype had one more CpG site because of the mutation), and into two genotypes, AA- and GG-based on L2 locus. The results showed that only L1 locus was significantly associated with body weight (P < 0.01), gonad weight (P ≤ 0.05), triiodothyronine (T3) level (P ≤ 0.05) and mRNA expression (P < 0.01). At L1 locus, newly created CpG site in GG genotype was highly methylated (93.3 %), while there was no difference of methylation level in the other two CpG sites among three genotypes. AA genotype and AG genotype having higher T3 level were significantly different (P ≤ 0.05) from GG genotype. There were significant differences among body weights of AA, AG and GG genotypes (P < 0.01). Gonad weights of AA genotype and AG genotype were significantly lower than GG genotype. The GHR1 mRNA expression of GG genotype was significantly lower than AA and AG genotypes (P < 0.01). These implied that mutations and methylation status of GHR1 gene might influence the hormone level, growth traits and gene expression in male half-smooth tongue sole and the L1 locus could be regarded as a potential candidate genetic and epigenetic marker in half-smooth tongue sole selection.

Antineoplastic therapy combined with whole brain radiation compared with whole brain radiation alone for brain metastases: a systematic review and meta-analysis

BACKGROUND

The standard treatment for brain metastases is whole brain radiation, but the medium survival is about 3-10 months and hadn't be improved for years.

AIM

This study was to evaluate the effect of antineoplastic therapy combined with whole brain radiation for brain metastases.

MATERIALS AND METHODS

We searched PubMed, EMBASE, Cochrane Library, Chinese Biomedical Literature Database, China Journal Full Text Database and references of the included studies up to May 2011. Randomized controlled trials involving antineoplastic combined with whole brain radiation compare with whole brain radiation alone for brain metastases were analysed. Study selection, data collection and quality assessment of studies were performed by two individual reviewers according to the Cochrane Handbook for systematic reviews of interventions 5.0.2. Statistic analyses were calculated using RevMan5.0.17 software. 9 randomized controlled trails, a total of 1582 patients were included.

RESULTS

There were no significant differences in overall survival, six to twenty-four months survival rate and death from central nervous system (CNS) cause, only the objective response rate was statistically higher in the combined group. (RR = 1.47, 95% CI: 1.10, 1.97; p = 0.009) Subgroup analysis of lung cancer got the same result, except that death from central nervous system (CNS) cause was higher in the combined therapy group, it was statistical significant (RR = 0.70, 95% CI: 0.53, 0.93; p = 0.01).

CONCLUSIONS

The benefit of antineoplastic combined with whole brain radiation for brain metastases was not concerned, either in the brain metastases from unselected primary tumors or lung cancer.

Biosynthesis of cyclic diterpene hydrocarbons in rice cell suspensions: conversion of 9,10-syn-labda-8(17),13-dienyl diphosphate to 9beta-pimara-7,15-diene and stemar-13-ene

The biosynthesis of diterpene hydrocarbons with enzyme extracts from rice cell suspension cultures was investigated to verify proposed pathways and intermediates in the production of the momilactone and oryzalexin phytoalexins. Diterpene synthase activity in cells treated with chitin to elicit the phytoalexin response was compared with the activity in untreated cells using the acyclic substrates [1-3H](E,E,E)- and [1-3H] (E,Z,E)-geranylgeranyl diphosphates (GGPPs 4-OPP and 11-OPP) as well as the bicyclic substrates [15-3H]ent-copalyl and [15-3H] syn-copalyl diphosphates (CPPs, 5-OPP, and 6-OPP). ent-kaurene (7), ent-sanda, racopimaradiene (8), 9 beta H-pimara-7,15-diene (9), and stemar-13-ene (10) were identified as major products by comparisons with authentic standards. Marked increases in diterpene synthase activities were observed with enzyme from chitin-treated cells: (E,E,E)-GGPP (approximately 100 fold), ent-CPP (approximately 3 fold), and syn-CPP (approximately 60 fold). The very low conversions of (E,Z,E)-GGPP to hydrocarbon products excludes its role in the biosynthesis of 9,10-syn-diterpenes in rice cells. ent-Kaurene was the major diterpene formed from ent-CPP with enzyme from unelicited cells. In contrast the enzyme from chitin-treated cells converted ent-CPP to a mixture of ent-kaurene, ent-sandaracopimaradiene, and a third unidentified diterpene. With syn-CPP as substrate the induced syntheses afforded a mixture of 9 beta-pimaradiene, stemarene, and a third, unidentified syn-diterpene. Overall the results are consistent with the hypothesis that rice cells respond to treatment with chitin fragments by producing new diterpene synthases not present in the untreated cells. These induced cyclases initiate phytoalexin biosynthesis by diverting (E,E,E)-GGPP into new cyclization modes that produce ent-sandaracopimaradiene, stemarene, and 9 beta-pimaradiene, the presumed precursors to oryzalexins A-F, oryzalexin S, and momilactones A-C, respectively. The intermediate role of 9,10-syn-CPP in syn diterpene biosynthesis is verified.

Elicitation of Diterpene Biosynthesis in Rice (Oryza sativa L.) by Chitin

Cell-free extracts of UV-irradiated rice (Oryza sativa L.) leaves have a much greater capacity for the synthesis from geranylgeranyl pyrophosphate of diterpene hydrocarbons, including the putative precursors of rice phytoalexins, than extracts of unstressed leaves (KA Wickham, CA West [1992] Arch Biochem Biophys 293: 320-332). An elicitor bioassay was developed on the basis of these observations in which 6-day-old rice cell suspension cultures were incubated for 40 hours with the substance to be tested, and an enzyme extract of the treated cells was assayed for its diterpene hydrocarbon synthesis activity as a measure of the response to elicitor. Four types of cell wall polysaccharides and oligosaccharide fragments that have elicitor activity for other plants were tested. Of these, polymeric chitin was the most active; a suspension concentration of approximately 7 micrograms per milliliter gave 50% of the maximum response in the bioassay. Chitosan and a branched beta-1,3-glucan fraction from Phytophthora megasperma f. sp. glycinea cell walls were only weakly active, and a mixture of oligogalacturonides was only slightly active. A crude mycelial cell wall preparation from the rice pathogen, Fusarium moniliforme, gave a response comparable to that of chitin, and this activity was sensitive to predigestion of the cell wall material with chitinase before the elicitor assay. N-Acetylglucosamine, chitobiose, chitotriose, and chitotetrose were inactive as elicitors, whereas a mixture of chitin fragments solubilized from insoluble chitin by partial acid hydrolysis was highly active. Constitutive chitinase activity was detected in the culture filtrate and enzyme extract of cells from a 6-day-old rice cell culture; the amount of chitinase activity increased markedly in both the culture filtrate and cell extracts after treatment of the culture with chitin. We propose on the basis of these results that soluble chitin fragments released from fungal cell walls through the action of constitutive rice chitinases serve as biotic elicitors of defense-related responses in rice.