Migration and spread of Bacillus cereus in mice with endophthalmitis and influence on inflammation / 中华微生物学和免疫学杂志

Objective:To investigate the causes of strong pathogenicity of Bacillus cereus ( B. cereus) in a mouse model of B. cereus endophthalmitis and the factors that might be related to the prognosis of the disease. Methods:C57BL/6J mice aged 6-8 weeks were injected with 1 μl PBS solution containing 100 CFU B. cereus into the vitreous cavity to construct traumatic endophthalmitis model, and a control group was set up by injecting the contralateral eyeball with 1 μl sterile PBS. A mouse model of Staphylococcus epidermidis ( S. epidermidis) endophthalmitis was constructed in the same way as disease control group. Real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to detect the levels of inflammatory cytokines at different time points. Histology, electroretinogram and transmission electron microscopy were used to detect the progression of endophthalmitis and retinal function at different time points. Results:B. cereus grew significantly faster than S. epidermidis in the eyes of C57BL/6 mice and gradually moved to the cornea 12 h after infection. The results of transmission electron microscopy showed that many more B. cereus were found in the iris with sparse pigment particles, while S. epidermidis could not be detected in the anterior segment after infection. The electroretinogram results showed that the amplitude of A wave and B wave of mice with B. cereus endophthalmitis decreased significantly 6 h after infection, and the B wave could not be detected 12 h after infection. Moreover, the amplitude reduction at different time points was significantly larger than that in the S. epidermidis endophthalmitis group. Histological examination found that compared with the S. epidermidis endophthalmitis group, the mice with B. cereus endophthalmitis had significantly increased inflammatory cells in the anterior chamber and vitreous cavity with a higher degree of infiltration, which was more destructive to the tissue structure. ELISA results showed that the activity of myeloperoxidase (MPO) was significantly stronger in the B. cereus endophthalmitis group than in the S. epidermidis endophthalmitis group, suggesting that a much more severe inflammation was induced. The expression of IL-6, TNF-α and IL-1β at the transcription and protein levels in the mouse model of B. cereus endophthalmitis were significantly higher than those in the mice with S. epidermidis endophthalmitis. Conclusions:B. cereus could induce severe endophthalmitis and tissue destruction in the eye due to its rapid growth and migration ability, which was an important factor leading to vision loss.

Necessity and feasibility of viral RNA detection in specialist ophthalmic institute during the COVID-19 epidemic / 中华实验眼科杂志

The prevention and treatment of COVID-19 in China is now at a key stage. The tasks faced by the medical organs are fighting against the COVID-19 while providing the medical services orderly. As a Specialist medical institution nationwide, ophthalmic hospitals are resuming receiving patients and performing operations gradually, including precision interruption of the epidemic, prevention of the secondary virus transmission, and avoidance of nosocomial cross infection among health care providers are required. We explored a multifaceted management for the prevention and control of epidemic, with a special focus on the individual protection for patients and medical staffs. A preliminary positive effect can be observed as a result. The main measures taken cover two aspects. On the one hand, 2019-nCoV ribonucleic acid (RNA) detection and hematological indices inspection including C-reactive protein (CRP) and serum amyloid A (SAA) are listed as routine tests of preoperative screening for ocular surgical patients. These tests are required to be completed upon the admission to avoid the possibility of accepting any asymptomatic infected individual and to reduce the risk of nosocomial cross infection. On the other hand, the 2019-nCoV RNA detection is also provided to high-risk employees who visited affected area recently. This assists in obtaining guarantee in both safety and quality of medical services provided, but also helps in lessening the mental and spiritual stress for medical staffs. It is expected that these measures can contribute to the work of our peers of ophthalmology in the prevention and control of COVID-19 and to the safe environment where the medical services are provided, and provide a reference for other outbreak of virus-causing disease.

Necessity and feasibility of viral RNA detection in specialist ophthalmic institute during the COVID-19 epidemic / 中华实验眼科杂志

The prevention and treatment of COVID-19 in China is now at a key stage.The tasks faced by the medical organs are fighting against the COVID-19 while providing the medical services orderly.As a Specialist medical institution nationwide, ophthalmic hospitals are resuming receiving patients and performing operations gradually, including precision interruption of the epidemic, prevention of the secondary virus transmission, and avoidance of nosocomial cross infection among health care providers are required.We explored a multifaceted management for the prevention and control of epidemic, with a special focus on the individual protection for patients and medical staffs.A preliminary positive effect can be observed as a result.The main measures taken cover two aspects.On the one hand, 2019-nCoV ribonucleic acid (RNA) detection and hematological indices inspection including C-reactive protein (CRP) and serum amyloid A (SAA) are listed as routine tests of preoperative screening for ocular surgical patients.These tests are required to be completed upon the admission to avoid the possibility of accepting any asymptomatic infected individual and to reduce the risk of nosocomial cross infection.On the other hand, the 2019-nCoV RNA detection is also provided to high-risk employees who visited affected area recently.This assists in obtaining guarantee in both safety and quality of medical services provided, but also helps in lessening the mental and spiritual stress for medical staffs.It is expected that these measures can contribute to the work of our peers of ophthalmology in the prevention and control of COVID-19 and to the safe environment where the medical services are provided, and provide a reference for other outbreak of virus-causing disease.

Identification of hemolysin BL from Bacillus cereus of patients with endophthalmitis and its biological activity detection in vitro / 中华微生物学和免疫学杂志

Objective To identify the hemolysin BL(HBL) gene from Bacillus cereus of patients with endophthalmitis comfirmed by API bacterial identification test strip,and detect its biological activity in vitro.Methods Three pairs of specific primers were designed according to the gene sequence of HBL(B,L1 and L2 components),then the PCR assay were established through condition optimization,and to further detect five Bacillus cereus strains isolated from clinical patients with endophthalmitis.HBL with biological activity was extracted by salt fractionation from a randomly selected strain,and a series of different concentrations of HBL were prepared and acted on sheep red blood cells(SRBC),Vero cells and Hela cells; virulence of HBL was also assessed through observating lethal effect of which on mice with intraperitoneal injection.Results Three genes of HBL were detected in all B.cereus strains from clinical patients; Strong hemolytic activity of HBL showed obvious time-and dose-dependent.In the study,we found the morphological changes of Vero and Hela cells caused by HBL were different,but cell death were the same result with contents released; Within 48 h after infection,lethality of HBL for mice showed 100％ with the concentration of more than 2.0 HU/ml,and was also in a time-and dose-dependent manner.Conclusion HBL isolated from B.Cereus had high hemolysis activity and low concentration.The expression of all BL genes provided a strong basis for the clinical feature of B.Cereus infection,which was developed rapidly and with a poor prognosis.It also provided a new method for rapid diagnosis and molecular epidemiology investigation in clinical.

Establishment of a method for detection of IVS-2-654 (C＞T) and -28 (A＞G) gene mutations by high-resolution melting analysis in β-thalassemia and its clinical application / 中华检验医学杂志

Objective To establish a method for detection of gene mutations in β-thalassemia by high-resolution melting (HRM) and study its preliminary clinical application.Methods Two common mutations [ IVS-2-654 ( C ＞ T ) and -28 ( A ＞ G ) ]of β-thalassemia in Wenzhou city population were selected.The plasmid DNA fragments of these mutations were constructed by TA clone technology as PCR templates or genotyping controls.A method for detection of β-thalassemia gene mutations based on HRM analysis was established and its specificity,sensitivity and repeatability were methodologically evaluated.One hundred and seventeen patients with clinically suspected β-thalassemia from Second Affiliated Hospital and Yu ying Children's Hospital of Wenzhou Medical College were enrolled into this study.The genomic DNA was extracted from whole blood cells and detected by HRM method.The results were compared with the direct sequencing data.Results HRM method could detect the mutations [ IVS-2-654( C ＞ T) and -28 ( A ＞ G ) ]of β-thalassemia and the results did not show any non-specific amplified fragments.All within-run and between-run coefficients of variation for different DNA types' Tm were smaller than 0.1％.And minimum 103 copies of DNA of each assay and 10％ mutation could be determined by this method.One hundred and seventeen patients with clinically suspected β-thalassemia were detected with HRM and all the results were in accordance with direct DNA sequencing.There were 45 IVS-2-654 ( C ＞ T)heterozygous mutation and 9-28 ( A ＞ G)heterozygous mutation and none homozygous mutation.Conclusion The method of rapid identification of β-thalassemia gene mutations based on HRM analysis is successfully established,which is a convenient,rapid,specific,sensitive and accurate technique for screening gene mutations in β-thalassemia as well as a general technical platform to identify other gene mutations.

Synthesis and anti-tubercular activity of novel alkyl substituted riminophenazine derivatives / 药学学报

A series of novel riminophenazine derivatives bearing an alkyl substituent attached to N-5 and imino nitrogen at C-3 position of the phenazine ring were obtained through rational drug design, aiming to maintain high anti-tubercular activity, lower toxicity and reduce lipophilicity. All target compounds were prepared by utilizing simple and flexible synthetic route and evaluated against Mycobacterium tuberculosis H37Rv and screened for mammalian cytotoxicity. The results demonstrated that compounds with a cyclopropyl substituent at N-5 position were more active than the reference compound clofazimine. In particular, 2-(4-chloroanilino)-5-cyclopropyl-3-(4-methoxycyclohexyl) imino-3, 5-dihydrophenazine (25) was found to be the most potent compound with low cytotoxicity and lipophilicity. This compound could serve as a valuable lead molecule for further optimization.

Analysis of β-globin gene mutation in β-thalassemia in Han population of Wenzhou region / 中华检验医学杂志

Objective To analysis the β-globin gene mutation in β-thalassemia in the population of Wenzhou natives,and identify the major mutation in Wenzhou and further provide valuable information for genetic counseling,prenatal diagnosis and prevention programs in this region.Methods Patients with β-thalassemia were diagnosed and the genomics DNA were extracted from whole blood cells and amplified with PCR,sequenced and compared to the standard sequence.Some mutations were further identified by subcloned.Results 44 of 66 patients were diagnosed β-Thalassemia,9 mutations were found in the 44 sporadic patients with the sequence analysis,2 of which were known polymorphisms(exonl 59,IVS-2-665),3 belonged to the common mutations in Chinese(IVS-2-654,CD_(41/42)-TTCT and TATA box nt-28),2 were scarce abnormalities(CD_(47),CD_(66))and 2 novel variants(-24T→C,CD_(26A)→G,same sense mutation,unreported).Conclusion The mutations of β-globin gene in Han Chinese in Wenzhou are complex (9 mutations found in all),the rare and novel mutations are identified,which provide the valuable information for genetic counseling in Wenzhou.

TpP and Early Diagnosis of Brain Infarction / 医学研究杂志

Objective To observe the relation between the changes of plasma TpP and D-dimer in patients with acute cerebral infarction( ACI).Methods D-dimer and thrombus precursor protein (TpP) levels in plasma of 55 cases with ACI during early phase and 25 normal healthy subjects were detected,and 24/55 cases were measured dynamically. D-dimer levels were detected by automated latex D-dimer immunoassay. Plasma TpP level was determined using a new assay,the TpP_ TM(USA),which is based on an ELISA method.Results There was significant difference(P

Investigation on Whole Blood Lead Levels in 2956 Children of 1/12～13 Years old in Wenzhou / 医学研究杂志

Objective To Inves tigate the blood lead levels of children of 1/12～13 years old in Wenzhou and early diagnose lead poisoning in them.Methods The whole blood lead levels of 2956 children aged 1/12～13 years were determined by atom absorbspectral analysis.Results The mean of all blood lead levels was(63.11?30.17)?g/L (2037 boys were 65.55?31.23?g/L,919 girls were 57.72?26.78?g/L),318 children(10.77%) were with a blood lead ≥100?g/L(259 boys,59 girls).The prevalence of lead poisoning in boys(12.7%)as higher than those in girls 6.4%(?~2=18.99,P

Changes of β-endorphin in both of plasma and CSF and its significance in children with acute encephaledema following infection of central nervous system / 临床儿科杂志

To explore the role of β-endorphin (β-EP) in the pathogenesis of the acute encephaledema, the levels of β-EP in both of plasma and CSF were determined by radioimmunoassay in 69 children with infection of central nervous system consisting of 39 cases with encephaledema and 30 cases without encephaledema, respectively. Another 19 cases without intracranial infection were as the control group. The results showed that the levels of plasma and CSF β-EP in the encephaledema group (50.74 ng/L±26.60ng/L，62.72ng/L±39.23ng/L) were significantly higher than those in without encephaledema group (32.78 ng/L±21.2ng/L，34.13ng/L±30.26ng/L)and the normal group (14.83ng/L±6.55ng/L，9.77ng/L±6.33ng/L)，respectively (P＜0.01).It is concluded that β-EP plays an important role in the occurrence and development of encephaledema in children with the infection of central nervous system.