[Phenotype and genotype analyses of two pedigrees with inherited fibrinogen deficiency]

Objective: To analyze the phenotype and genotype of two pedigrees with inherited fibrinogen (Fg) deficiency caused by two heterozygous mutations. We also preliminarily probed the molecular pathogenesis. Methods: The prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and plasma fibrinogen activity (Fg∶C) of all family members (nine people across three generations and three people across two generations) were measured by the clotting method. Fibrinogen antigen (Fg:Ag) was measured by immunoturbidimetry. Direct DNA sequencing was performed to analyze all exons, flanking sequences, and mutated sites of FGA, FGB, and FGG for all members. Thrombin-catalyzed fibrinogen polymerization was performed. ClustalX 2.1 software was used to analyze the conservatism of the mutated sites. MutationTaster, PolyPhen-2, PROVEAN, SIFT, and LRT online bioinformatics software were applied to predict pathogenicity. Swiss PDB Viewer 4.0.1 was used to analyze the changes in protein spatial structure and molecular forces before and after mutation. Results: The Fg∶C of two probands decreased (1.28 g/L and 0.98 g/L, respectively). The Fg∶Ag of proband 1 was in the normal range of 2.20 g/L, while it was decreased to 1.01 g/L in proband 2. Through genetic analysis, we identified a heterozygous missense mutation (c.293C>A; p.BβAla98Asp) in exon 2 of proband 1 and a heterozygous nonsense mutation (c.1418C>G; p.BβSer473*) in exon 8 of proband 2. The conservatism analysis revealed that Ala98 and Ser473 presented different conservative states among homologous species. Online bioinformatics software predicted that p.BβAla98Asp and p.BβSer473* were pathogenic. Protein models demonstrated that the p.BβAla98Asp mutation influenced hydrogen bonds between amino acids, and the p.BβSer473* mutation resulted in protein truncation. Conclusion: The dysfibrinogenemia of proband 1 and the hypofibrinogenemia of proband 2 appeared to be related to the p.BβAla98Asp heterozygous missense mutation and the p.BβSer473* heterozygous nonsense mutation, respectively. This is the first ever report of these mutations.

[Phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection]

Objective: To analyze the phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection (CoECO), and provide clues for empirical antibiotics treatment. Methods: The strains of Escherichia coli isolated from blood and abdominal samples in the Department of Laboratory Medicine of the First Medical Center of the PLA General Hospital from 2010 to 2020 were retrospectively analyzed. Mass spectrometer was used to identify all of the strains and the minimum inhibitory concentration (MIC) were detected by VITEK 2 Compact. All isolates were sequenced by 2×150 bp double terminal sequencing strategy on the HiSeq X Ten sequencer (Illumina). After the genome sequence was spliced, the single nucleotide polymorphism (SNP) analysis of the strain sequence was performed using kSNP3 software to clarify the homologous relationship between strains. If the strains isolated from two different parts had high homology, they were regarded as the same strain and the case was with CoECO infection. Meanwhile, the multilocus sequence type (MLST) was determined using PubMLST website and resistant genes were screened by CARD website. Results: A total of 70 cases of CoECO infection were screened, including 45 males and 25 females, and aged (59.2±16.3) years old. The 70 CoECO isolates belonged to 35 sequence types (STs). The most prevalent STs included ST38 (n=6), ST 405 (n=6), ST 1193 (n=6) and ST131 (n=5), and other ST types contained less than 5 strains. The homologous relationship among strains was relatively scattered, presenting a sporadic trend as a whole, and only a few strains had a small-scale outbreak. The CoECO isolates showed significantly resistance to ampicillin (91.4%, 64/70), ampicillin/sulbactam (74.3%, 5 2/70), ceftriaxone (72.9%, 51/70), ciprofloxacin (71.4%, 50/70) and levofloxacin (71.4%, 50/70), and high-sensitivity to piperacillin/tazobactam, carbapenems and amikacin. The most prevalent resistant gene was tet (A/B) (70%, 49/70), followed by bla_TEM (58.6%, 41/70), sul1 (55.7%, 40/70), sul2 (54.3%, 38/70), bla_CTX-M-14(25.7%, 18/70), bla_CTX-M-15(17.1%, 13/70), bla_CTX-M-55(15.7%, 11/70), bla_CTX-M-64/65(5.7%, 4/70), bla_CTX-M-27(4.3%, 3/70), mcr-1 (4.3%, 3/70), bla_NDM-5(2.9%, 2/70). Conclusions: CoECO is distributed dispersedly and has no obvious advantage clone. No genotype with obvious advantages was found. Although the strain has a high resistance rate to some antibacterial drugs, the proportion of carrying resistant genes is low, and it has a high sensitivity to some first-line antibacterial drugs.

[Research progress on the relationship between persistent organic pollutants and gestational diabetes]

Gestational diabetes mellitus(GDM)is one of the common complications during pregnancy. It is associated with many adverse pregnancy outcomes, threatening maternal and child health seriously. The exact pathogenesis of GDM remains unclear. Long term exposure to persistent organic pollutants (POPs) is considered to be one of the risk factors for GDM. More and more studies are concerned about the relationship between them. Based on the literature published at home and abroad, this article summarizes the correlation and possibly related mechanism of POPs and GDM, and explores the correlation between pops and GDM, so as to provide a new idea for the prevention of gestational diabetes.

A novel double-variant RHAG allele leads to Rhmod phenotype

AIMS/OBJECTIVES

We aimed to analyse the molecular backgrounds and red blood cell (RBC) antigen expression of a male blood donor with Rh_mod phenotype and his family members.

BACKGROUND

Rh deficiency phenotypes are rarely found worldwide and are characterised by the lack of Rh antigen expression on RBCs. During routine screening, we found a blood donor who seemingly lacked Rh antigens. Therefore, we recruited the donor and his family for further investigation.

METHODS

RBC serotyping and antibody screening/identification were performed for each sample. A routine blood examination was also conducted. RHD, RHCE and RHAG were sequenced at the genomic DNA or RNA level. Eleven antigens or proteins associated with Rh complex were tested using flow cytometry analysis.

RESULTS

The proband and one of his brothers showed extremely weak D antigen and Rh expression levels but did not manifest anaemia. Most of the expressed RBC antigens of the two Rh-deficient individuals were similar to the previously reported cases but with some exceptions. Molecular analyses demonstrated homozygous expression of a novel RHAG allele, namely, c.[572G>A;707A>C], both in the proband and one of his brothers.

CONCLUSIONS

To our knowledge, we identified the second double-variant RHAG allele and the first one related to Rh_mod phenotype. The novel allele was also confirmed to be heritable by family analyses.

[Analysis of antimicrobial resistance and risk factors of community-onset methicillin-resistant staphylococcus aureus infection]

Objective: To analyze risk factors and drug resistance of community-onset methicillin-resistant staphylococcus aureus (CO-MRSA) infection through the investigation of patients infected with CO-MRSA. Methods: The clinical data of 97 cases infected with community-onset staphylococcus aureus (COSA) was collected in this hospital from July 2016 to June 2017. Epidemiological survey method and the variables were determined according to expert consultation, literature and practical work experience. Results: Among 97 patients infected with COSA, the diagnosis rate of CO-MRSA was 21.65%(21/97). The drug sensitivity results showed that: CO-MRSA was high resistant to erythromycin, tetracycline and clindamycin, and the drug resistance rate exceeded 50%. Multiple variables were analyzed by Logistic regression. The usage of antimicrobial agents in the past three months and the history of hospitalization within one year were the independent risk factors. The MRSA infection rate was 57.89%(11/19) of the persons who had taken antibacterial agents in the recent three months.The MRSA infection rate was 48.28%(14/29) of the persons who had been hospitalized in the past one year. OR value of two risk factors was respectively 10.006(95%CI: 2.200-45.519, P=0.030) and 11.519(95%CI: 2.405-55.177, P=0.002). Conclusions: Most COSA is sensitive to methicillin, but CO-MRSA is multidrug resistant and has more risk factors. The clinicians should reasonably use the antibacterial agents according to the drug sensitivity in order to prevent the occurrence of multidrug resistant MRSA.

[Current status of job burnout in clinical nurses in a grade A tertiary hospital and related influencing factors]

Objective: To investigate the current status of job burnout in clinical nurses in a grade A tertiary hospitalin Shaoxing,China and related influencing factors. Methods: In October 2016, the Nursing Burnout Scale (NBS)was used for the investigation of 304 clinical nurses in a grade A tertiary hospital.The contents of the investigation included general data(including age,education background,working years,marital status, frequency of night shifts,professional title, and way of employment), characteristics of working environment,burnout, personality characteristics,coping strategy,and psychosomatic symptoms.SPSS 18.0 was used to conduct Pearson correlation analysis of the scores of each dimension of NBS. A multivariate regression analysis was performed with the demographic features of clinical nurses as the independent variable and the scores of each dimension of NBS as the dependent variable. Results: Among the clinical nurses in this grade A tertiary hospital, the incidence rate of severe burnout was 74%.The Pearson correlation analysis showed that burnout,pessimistic personality,negative coping,and psychosomatic symptoms were positively correlated with working environment(r=0.530,0.316,0.116,and 0.502); pessimistic personality and psychosomatic symptoms were positively correlated with burnout(r=0.618 and 0.675); psychosomatic symptoms were positively correlated withpessimistic personality(r=0.540); negative coping was negatively correlated with pessimistic personality(r=-0.145).The multivariate linear regression analysis showed that department(Department of Internal Medicine or Department of Surgery,B=-0.364 and -0.428)and frequency of night shifts(<6 times/month and 6-10 times/month,B=0.199 and 0.256)were influencing factors for the score of working environment; department(Department of Internal Medicine or Department of Surgery, B=-0.350 and -0.360)was an influencing factor for the score of burnout; 1-3 working years(B=-0.238)was an influencing factor for the score of pessimistic personality; married state,1-3 working years,and department (Department of Internal Medicine or Department of Surgery)were influencing factors for the score of psychosomatic symptoms(B=0.263,-0.301,-0.322,and -0.391). Conclusion: There is a high incidence rate of job burnout among clinical nurses in this grade A tertiary hospital,which is associated with burnout,working environment, pessimistic personality,and psychosomatic symptoms.Marital status,working years,department,and frequency of night shifts are major influencing factors for job burnout.

Myocyte enhancer factor 2C regulation of hepatocellular carcinoma via vascular endothelial growth factor and Wnt/β-catenin signaling

Hepatocellular carcinoma (HCC) is one of the leading malignancies worldwide. Myocyte enhancer factor 2C (MEF2C) was traditionally regarded as a development-associated factor and was recently reported to be an oncogene candidate. We have previously reported overexpression of MEF2C in HCC; however, the roles of MEF2C in HCC remain to be clarified. In this study, HCC cell lines and a xenograft mouse model were used to determine the functions of MEF2C in vitro and in vivo, respectively. Specific plasmids and small interfering RNA were used to upregulate and downregulate MEF2C expression, respectively. Functional assays were performed to assess the influence of MEF2C on cell proliferation, and VEGF-induced vasculogenic mimicry, migration/invasion as well as angiogenesis. Co-immunoprecipitation was conducted to identify the interaction of MEF2C and β-catenin. Human HCC tissue microarrays were used to investigate correlations among MEF2C, β-catenin and involved biomarkers. MEF2C was found to mediate VEGF-induced vasculogenic mimicry, angiogenesis and migration/invasion, with involvement of the p38 MAPK and PKC signaling pathways. However, MEF2C itself inhibited tumor growth in vitro and in vivo. MEF2C was upregulated by and directly interacted with β-catenin. The nuclear translocation of β-catenin blocked by MEF2C was responsible for MEF2C-mediated growth inhibition. The nuclear translocation of MEF2C was associated with intracellular calcium signaling induced by β-catenin. HCC microarrays showed correlations of nuclear MEF2C with the angiogenesis-associated biomarker, CD31, and cytosolic MEF2C with the proliferation-associated biomarker, Ki-67. MEF2C showed double-edged activities in HCC, namely mediating VEGF-induced malignancy enhancement while inhibiting cancer proliferation via blockade of Wnt/β-catenin signaling. The overall effect of MEF2C in HCC progression regulation was dictated by its subcellular distribution. This should be determined prior to any MEF2C-associated intervention in HCC.

Differential sensitivity of various pediatric cancers and squamous cell carcinomas to lovastatin-induced apoptosis: therapeutic implications

3-Hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase is the rate-limiting enzyme of the mevalonate pathway, the diverse array of end products of which are vital for a variety of cellular functions, including cholesterol synthesis and cell cycle progression. We showed previously that this enzyme holds a critical role in regulating tumor cell fate, including cell death, as its expression is down-regulated in response to retinoic acid, a potent anticancer therapeutic. Indeed, direct inhibition of HMG-CoA reductase with lovastatin, a competitive inhibitor of this enzyme, induced a pronounced apoptotic response in neuroblastoma and acute myeloid leukemic cells. We have now extended this work and evaluated a wide variety and large number of tumor-derived cell lines for their sensitivity to lovastatin-induced apoptosis. These cell lines were exposed to a wide range (0-100 microM) of lovastatin for 2 days and assayed for cell viability using the 3,4,5-dimethyl thiazlyl-2,2,5-diphenyltetrazolium bromide assay and the induction of apoptosis by flow cytometric and ultrastructural analyses. Lovastatin induced a pronounced apoptotic response in cells derived from juvenile monomyelocytic leukemia, pediatric solid malignancies (rhabdomyosarcoma and medulloblastoma), and squamous cell carcinoma of the cervix and of the head and neck. Interestingly, the subset of malignancies that are particularly sensitive to lovastatin-induced apoptosis correspond to those tumor subtypes that are sensitive to the biological and antiproliferative effects of retinoids in vitro. The nature of the biologically active form of lovastatin has been challenged recently as the growth-inhibitory effects of this drug were attributed to its prodrug lactone form that does not inhibit HMG-CoA reductase function. In this report, we demonstrate that the apoptotic properties of lovastatin are triggered by the open ring acid form that is a potent inhibitor of HMG-CoA reductase activity. Thus, we have identified a subset of tumors that are sensitive to lovastatin-induced apoptosis and show HMG-CoA reductase as a potential therapeutic target of these cancers.

Determination of lovastatin in human plasma using reverse-phase high-performance liquid chromatography with UV detection

The authors have developed a simple, rapid HPLC assay with ultraviolet (UV) detection for the analytical determination of lovastatin and its acid in human plasma for a concentration range of 100-5,000 ng/mL. Sample clean-up involved the use of C10 solid-phase extraction cartridges. Our limit of quantitation was 100 ng/mL. Standard curves were linear from 100 to 5,000 ng/mL, with a correlation coefficient (r2) of 0.999 +/- 0.0002. Stored samples were stable at -70 degrees C for up to 4 months prior to reversed-phase HPLC analysis. This assay was able to measure steady-state lovastatin concentration (Css) at the initial dose level in a phase I trial of lovastatin as a modulator of apoptosis.

Diagnosis and treatment of adrenal tumours: a review of 35 years' experience

OBJECTIVE

To review and analyse clinical data on the diagnosis and management of patients with adrenal masses.

PATIENTS AND METHODS

Patients admitted with adrenal masses between 1960 and 1995 were reviewed. The series comprised 116 males (mean age 41.4 years, SD 10.5, range 3-77) and 95 females (mean 36.9 years, SD 11.6, range 1-62); eight patients were < 14 years old and the overall mean (SD) age was 39.4 (12.8) years. The diagnosis was based on symptoms, signs, hormone levels and imaging studies. All tumours were confirmed by surgery, and pathology and results of analysis assessed statistically.

RESULTS

Over the last 35 years, the incidence of adrenal tumours was 1.7% of all patients admitted with genitourological diseases or 9.7% of patients with genitourinary tumours at our institution. The prevalence of adrenal tumours in males and females was similar but Cushing's syndrome was 3.1 times more frequent in females than in males and phaeochromocytoma 1.9 times more frequent in males than females. Most patients with adrenal tumour were aged 30-50 years. Of 211 adrenal tumours, 151 (72%) were functional, with a prevalence of benign tumour, and 60 (28%) were nonfunctional, with 35% malignant. There were 78 'incidentalomas' which included 18 functional tumours. Overall, 210 tumours were removed and one was explored. Correlation analysis between tumour size and character or hormone levels showed that size was significantly positively correlated with tumour character (r = 0.4010, P < 0.001), but there was no relationship between tumour size and hormonal levels. The postoperative complication rate was 3.3% and the mortality 0.5%.

CONCLUSIONS

Based on this analysis we recommend that computed tomography is the first method used to define and localize the adrenal masses, that hormone levels should be determined in symptomatic or asymptomatic patients with adrenal masses, and that functional adrenal tumours and solid incidentalomas of any size should be removed surgically.

Detection of Shigella and enteroinvasive Escherichia coli using polymerase chain reaction

Two oligonucleotide primers were used in a polymerase chain reaction (PCR) procedure to amplify a region of the invasive-associated locus (ial) of Shigella and enteroinvasive Escherichia coli (EIEC). Detection of the amplified product can be done by agarose gel electrophoresis, which is specific and sensitive enough for routine diagnosis of these two pathogens. PCR is done using DNA extracted directly from faeces. The procedure can be completed in 7 h. These findings demonstrate a novel method for rapid, sensitive, specific, and simple diagnosis of diarrhoea caused by Shigella and EIEC.