[Study on the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A]

Objective: To summarize the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A. Methods: In the retrospective study, a total of 1 226 clinical isolates from suspected multidrug-resistant pulmonary tuberculosis patients in Beijing TB control system from 2016 to 2021 were identified as Mycobacterium tuberculosis (MTB) strains by MPB64 antigen detection test. Rifampicin-resistant tuberculosis (RR-TB) strains were screened by the phenotypic drug susceptibility using the proportion method. The drug susceptibilities of Levofloxacin(LFX), Moxifloxacin(MFX), Bedaquiline(BDQ) and Linezolid(LZD)were detected by the phenotypic drug susceptibility with microplate method. The drug resistance rate, drug resistance level and minimum inhibitory concentration (MIC) distribution of four anti-tuberculosis drugs in group A were analyzed. We calculated the demographic distribution of RR-TB, multidrug-resistant tuberculosis(MDR-TB), pre-extensively drug resistant tuberculosis (pre-XDR-TB), extensively drug resistant tuberculosis (XDR-TB) patients and the cross resistance of LFX and MFX, then summarized the drug-resistance spectrum of BDQ-resistant and LZD-resistant strains and the treatment outcome of RR-TB patients. Measurement data were expressed as rate or composition ratio,χ2 test was used between and within groups, and P<0.05 was considered statistically significant. Results: Among the 1 226 suspected multidrug-resistant pulmonary tuberculosis patients, the detection rates of RR/MDR/pre-XDR/XDR-TB patients were 20.8%(255/1 226), 15.2%(186/1 226), 5.7%(70/1 226), 0.5%(6/1 226), respectively. There were statistically significant differences in the distribution of patients with the four types of drug resistance in terms of age and treatment history (χ2=14.95, P=0.020;χ2=15.91, P=0.001). The drug resistance rates of LFX, MFX, BDQ and LZD in RR-TB patients were 27.5% (70/255), 27.5% (70/255), 0.4% (1/255) and 2.4% (6/255), respectively. The MICs of LFX, MFX and LZD-susceptible MTB were mainly at 0.25 mg/L, and the MIC of BDQ-susceptible MTB was mainly concentrated at 0.03 mg/L. 25.1% (64/255) of the RR MTB were resistant to both LFX and MFX, and 6 strains were resistant to LFX or MFX, showing incomplete two-way cross resistance. One BDQ-resistant strain and six LZD-resistant strains were detected. The treatment success rate of RR-TB patients was 74.4% (151/203), and there were statistically significant differences in treatment outcomes between resistant and sensitive patients on the LFX-containing treatment regimen (Fisher's exact test, P=0.012). Conclusions: The prevalence of fluoroquinolones (LFX and MFX) resistance in rifampicin-resistant MTB is very serious. LFX and MFX show incomplete bidirectional cross-resistance. BDQ and LZD have the most promising future in the treatment of MDR-TB. Improve drug-resistance testing will help to further improve the success rate of treatment.

CuCl2 -Catalyzed α-Chloroketonation of Aromatic Alkenes via Visible-Light-Induced LMCT

Here we report a copper-catalyzed protocol for the synthesis of α-chloroketones from aromatic alkenes including electron-deficient olefins under visible-light irradiation. Preliminary mechanistic studies show that the peroxo Cu(II) species is the key intermediate and hydroperoxyl (HOO⋅) and chlorine (Cl⋅) radicals can be generated by ligand-to-metal charge transfer (LMCT).

[Analysis on characteristic of pulmonary tuberculosis cases reported in children from four provinces in China, 2019-2021]

Objective: To analyze the reported characteristics of pulmonary tuberculosis (TB) in children aged 0-14 years in four provinces (municipalities), Beijing, Hubei, Chongqing and Sichuan, in China, and provide evidence for the prevention and control of pulmonary TB in children. Methods: The incidence data of childhood pulmonary TB were collected from notifiable disease and tuberculosis management information system of Chinese information system for disease control and prevention,and descriptive epidemiological methods were used to analyze the medical care seeking flow, characteristics and management inclusion of pulmonary TB cases in children. Statistical analysis and data visualization were conducted with softwares Excel 2015, R 4.1.2 and Echart 4.7.0. Results: A total of 6 811 pulmonary TB cases in children were reported in the four provinces during 2019-2021, in which 4 741 (69.6%) were clinically diagnosed and 2 070 (30.4%) were laboratory confirmed. A total of 526 medical institutions reported TB cases in children, including 356 general hospitals (67.7%, 356/526) reporting 4 706 cases, 11 infectious disease hospitals (2.1%, 11/526) reporting 836 cases and 5 children's hospitals (1.0%, 5/526) reporting 542 cases. A total of 6 249 (91.7%) local cases and 562 (8.3%) non-local cases were reported. The reported local incidence rates of TB from 2019-2021 were 6.20/100 000, 7.10/100 000 and 7.20/100 000, respectively, showing an increase trend year by year. The sex ratio of the cases were 0.98∶1(3 373∶3 438). The cases were mainly distributed in age group 10-14 years (4 887 cases, 71.8%). The cases were mainly students (5 167 cases, 75.9%). The management inclusion rates of the local cases and non-local cases were 20.60% and 2.67%, respectively. Conclusions: The main medical institutions reporting pulmonary TB cases in children were children's hospitals, infectious disease hospitals and TB special hospitals, the incidence of pulmonary TB in children in Sichuan was higher. In 2020, the inter-provincial medical seeking behavior of the pulmonary TB cases decreased significantly. The incidence rate in boys was lower than that in girls, and children aged 10-14 years were the population with high incidence of pulmonary TB. The management inclusion rate in non-local cases was lower than that in local cases.

Visible imaging system with changeable field of view on the HL-2A tokamak

A new visible imaging system characterizing a flexible optical design and delivering high resolution frames is established on the HL-2A tokamak. It features a modular configuration, consisting of a front-end imaging lens, a set of bilateral telecentric relay lenses, and a camera. To avoid the effects of plasma radiation (x and gamma-rays) and magnetic field variation on the camera, it should be away from the coils. Therefore, the length of the relay lenses determines the total size of the imaging system. The main feature of this imaging system is to realize the variation of field of view (FOV) by interchanging the front-end prime lenses or by using a zoom lens directly rather than designing the optical system afresh, which lowers the cost drastically. The primary purpose of varying FOV is to enrich the versatility of this system, i.e., focusing on a narrow FOV such as gas puff imaging or a wide FOV such as the plasma cross sections. During the HL-2A experiments, this visible imaging system is used to provide high quality pictures of the plasma-wall interaction, divertor detachment, pellet injections, and so on. The frames confirmed that a strong radiation close to the X point is correlated with the completely detached inner target.

[Dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy]

Objective: To analyze the dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy (ART) in Dehong Dai and Jingpo autonomous prefecture, Yunnan province, and provide information support for the clinical use of HIV-1 DNA quantitative detection. Methods: The HIV infection cases in recent infection cohort from Dehong Center for Disease Control and Prevention during 2009-2018 were selected as study subjects. The dynamic curve of HIV-1 DNA load varrying with time was generated and logistic regression analysis was conducted to identify the risk factors for HIV-1 load in the recent follow up after ART and statistical analysis was performed by using SPSS 17.0. Results: Among the 113 HIV infection cases detected from the recent infection cohort, the recent HIV infection rate were 49.6%(56/113) males, sexual transmission cases and drug injection transmission cases accounted for 53.1% (60/113), 80.5% (91/113) and 19.5% (22/113), respectively. The dynamic changes curve showed that HIV-1 DNA load was relatively high (>800 copies /10⁶ PBMCs) before ART, and droped rapidly (<400 copies /10⁶ PBMCs) after ART for 1 year. However, HIV-1 DNA load decreased insignificantly from the second year of ART, and remained to be 269 copies/10⁶ PBMCs after ART for 6 years. Univariable logistic regression analysis indicated that OR (95%CI) of CD8, CD4/CD8 and HIV-1 DNA load were 1.00 (1.00-1.00), 0.30 (0.09-1.05) and 1.01 (1.00-1.01), respectively. Multivariable logistic regression analysis showed that OR value of HIV-1 DNA load base was 1.00 (1.00-1.01). Conclusions: HIV-1 DNA load decreased significantly in the first year of ART, then remained stable for years. HIV-1 DNA load base was the key factor associated with the decrease of HIV-1 DNA load, the lower the HIV-1 DNA load base, the lower HIV-1 DNA load. Therefore, earlier ART can contribute to the decrease of HIV-1 DNA load.

[Clinicopathological characteristics of rectal neuroendocrine neoplasms]

Objective: Clinicopathological characteristics of neuroendocrine neoplasms are highly heterogeneous based on variable origins.Our study aims to explore the clinical features of rectal neuroendocrine neoplasm (RNEN). Methods: Patients with histologically diagnosed rectal neuroendocrine neoplasms were retrospectively analyzed between January 2012 and December 2020. Epidemiological characteristics, clinical manifestations, complete blood count, endoscopy findings, and pathological features were recorded and analyzed. T-test was used for measurement data analysis, Chi-square test was performed for classification data analysis, and Binary logistic regression was applied for analyzing risk factors of metastasis. Results: Among 172 patients, the male to female ratio was 107 to 65 with an average age of (52±12) years (16-77 years). Altered bowel habit was the most common initial symptom (58/172, 33.7%), followed by abdominal pain (36/172, 20.9%) and loss of body weight (27/172, 15.7%). One hundred and sixty-one cases were neuroendocrine tumors, 9 were neuroendocrine carcinomas and 2 were mixed neuroendocrine-non-neuroendocrine neoplasms. Most endoscopic presentations were polypoid lesions (147/172, 85.5%), mainly limited to mucosa (48/172, 27.9%) and submucosa (96/172, 55.8%). Twenty-nine patients developed lymph node invasion or distant metastasis at diagnosis. There were statistical difference of neutrophil-to-lymphocyte ratios (NLR) among groups with different tumor size (<10 mm vs. 10-20 mm vs.>20 mm, mean NLR 1.79±0.55 vs. 2.27±1.23 vs. 2.95±0.66, P<0.01. Compared with non-metastatic group, the metastatic group presented higher NLR(2.61±0.81 vs. 1.89±0.80, P<0.01). Tumor size (<10 mm vs. 10-20 mm vs.>20 mm, OR 1.00 vs. 2.10 vs. 5.25×10⁹, P =0.001), invasion to bowel wall (mucosa vs. submucosa vs. muscularis vs. serosa invasion,OR 1.00 vs. 3.26 vs. 14.11 vs. 39.42, P=0.008), and NLR (NLR<2.25 vs. NLR≥2.25, OR 1.00 vs. 5.19, P =0.024) were risk factors for metastasis. Conclusion: Metastasis of RNEN is related with tumor size, degree of bowel invasion and NLR. High NLR is a poor prognostic factor of RNEN.

[Spatio-temporal distribution of pulmonary tuberculosis and influencing factors in Beijing, 2008-2018]

Objective: To understand the spatiotemporal distribution of pulmonary tuberculosis (TB) and influencing factors in Beijing from 2008 to 2018. Methods: The incidence data of pulmonary TB in Beijing from 2008 to 2018 were from Tuberculosis Information Management System of Chinese Disease Prevention and Control Information System. Software ArcGIS 10.2 was used to visualize the spatiotemporal distribution of pulmonary TB incidence. Getis's G_i^* statistic was applied to analyze the spatial clustering of pulmonary TB incidence at street/township scale. Bayesian spatiotemporal model was applied to analyze factors affecting its spatiotemporal distribution, including urbanization rate, GDP per capita, number of hospital beds per thousand population, permanent migrant population and population density. Results: The reported pulmonary TB incidence showed a downward trend in the past 11 years in Beijing, from 58.64/100 000 to 30.43/100 000. The incidences were higher in Tongzhou, Changping and other newly developed urban districts, with the hot spots concentrated in local areas of these districts. The incidences of pulmonary TB were lower in Dongcheng, Xicheng and other old urban districts-with the cold spots also concentrated in these area. The risk for the incidence of pulmonary TB was associated with the urbanization rate and the permanent migrant population. For every 1% increase in the urbanization rate, the relative risk of pulmonary TB would increase by 1%. For every 10 000 person increase of permanent migrant population, the relative risk of pulmonary TB would increase by 0.6%. Conclusions: In Beijing, the current pulmonary TB prevention and control needs to be focused on the newly developed urban areas. Due to the accelerated process of urbanization, it is necessary to strengthen TB prevention and control in permanent migrant population to reduce the incidence of TB in Beijing.

Visible wide-angle view imaging system for the first plasma on the HL-2M tokamak

The wide-angle view imaging system, in terms of a tangential view diagnostic with field of view (FOV) of 56.8° and a downward-looking diagnostic from the top of the machine with FOV of 94.7°, has been newly constructed for the first plasma of the HL-2M tokamak achieved in December 2020. Its mission in this stage is to monitor the plasma evolution during its startup, sustainment, and disruption in the visible spectral range as well as the plasma-wall interaction. For the latter ultrawide view diagnostic, nearly three-quarters of the divertor region and half the area of the inner wall are in the view range. Both the diagnostics are characterized by a similar optical structure, i.e., the light emission from the plasma is collected by a front-end lens and transferred through an imaging fiber bundle to the camera. This optical structure is suitable for application in the complex tokamak environment mainly because the fiber bundle is flexible. Photos of glow discharges are acquired prior to the first plasma for testing the FOVs in the vacuum vessel. The spatial resolution is ∼4mm for the tangential view diagnostic and ∼10mm for the downward-looking diagnostic. The temporal resolutions, ranging from 90 to 360 Hz by changing the region of interest or binning acquisition mode of the color camera, are applied to record the plasma evolutions and/or dust creation events during the first plasma campaign.

Fast charge exchange recombination spectroscopy on HuanLiu-2A tokamak

A Fast Charge eXchange Recombination Spectroscopy (CXRS) diagnostic with eight radial channels has been implemented on a HuanLiu-2A (HL-2A) tokamak with a time resolution of up to 10 kHz monitoring helium II spectra or 1 kHz monitoring carbon VI spectra. The crucial aspects of the fast CXRS are to improve the spectral intensity and the acquisition frequency. The spectral intensity has been greatly enhanced by customized fiber bundles. The main boost in optimizing the acquisition frequency is achieved by binning more pixel rows of the charge coupled device (CCD) representing one radial channel and by reducing the effective image area of the CCD. Consequently, the sawtooth oscillations of ion temperature and rotation velocity are continuously observed for the first time in the HL-2A tokamak.

Note: Real-time wavelength matching system designed for the motional Stark effect polarimeter on HL-2A tokamak

A 7-channel motional Stark effect diagnostic based on dual photo-elastic modulators is installed and operated routinely for rather low beam energy and magnetic field on the HL-2A tokamak, with a spatial resolution of ∼3 cm and a temporal resolution of 10 ms. The instrument observes the σ component of the full energy D_α from the first or the fourth ion source of a neutral beam injector. However, the change in beam energy during a discharge causes variation of the Doppler shift with the maximum of 1 Å, which leads to the polarization fraction drop from 30%-40% to 10% and then makes the signal-to-noise ratio of the system become very poor. Therefore, a real-time wavelength matching system is designed to promote polarization fraction. The beam emission spectra are filtered by using a monochrometer in real time. And a narrowband filter is tilted by using an absolutely calibrated rotator through beam energy in order to make sure that the deviation of wavelength matching is less than 0.1 Å.

[Normal values for solid state high resolution anorectal manometry in healthy adult volunteers]

Objective: To explore the normal values for two-dimension solid state high resolution anorectal manometry (HRAM) in healthy adult volunteers. Methods: The healthy adult volunteers were recruited by advertisement and underwent solid state HRAM in the left lateral position. Anorectal pressures and rectal sensation were recorded and analyzed. Results: (1) A total of 126 Chinese healthy adult volunteers (male: 50 cases (39.7%); age: (37.5±14.2) years old ) were recruited in this study. (2) Mean anal resting pressure (MERP) was (71.8±17.3) mmHg (1 mmHg=0.133 kPa). Maximum anal resting pressure (MARP) was (79.3±17.8) mmHg, Maximum anal squeeze pressure (MSP) was (178.7±52.8) mmHg. Anal high pressure zone (HPZ) length was (3.4±0.6) cm. During simulated evacuation, residual anal pressure (RAP) was (63.8±20.5) mmHg, and anal relaxation rate (ARR) was (37.0±11.5)%. Rectal threshold volume for first sensation (FST), desire to defecate (DDT), urgency to defecate (UDT) and maximum discomfort (MDT) was (47.4±10.0) ml, (84.5±18.2) ml, (125.8±28.5) ml, and (175.5±36.1) ml, respectively. (3) Compared with female subjects, male subjects had higher MSP[(211.0±50.7) mmHg vs (157.5±42.5) mmHg], RAP[(71.6±18.1) mmHg vs (58.8±20.5) mmHg]and rectal MDT[(187.0±36.4) mmHg vs (168.0±34.1)mmHg], but lower ARR[(32.1±8.0)% vs (40.2±12.3)%], all P<0.01. (4) MERP, MARP, MSP and rectal MDT were higher in young group (≤40 years old), all P<0.05. Conclusions: These observations provide normal values for two-dimension solid state HRAM, which have significant difference between genders and different age groups.

[Chronic liver disease increases with damage to intestinal barrier function]

Objective: To probe into the correlation between chronic liver disease and intestinal barrier function. Methods: 1 491 cases of hospitalized patients were enrolled, of which 741 cases were of chronic liver diseases, including 397 cases of fatty liver diseases, 230 cases of chronic hepatitis, 114 cases of liver cirrhosis, and 750 cases of non-hepatic diseases. All admitted patients' intestinal barrier function like diamine oxidase (DAO), D-lactate, lipopolysaccharide, and biochemical indicators of liver functions were tested. According to different data, statistical analysis was done using t-test, ANOVA, Dunnett's test, χ (2) test of fourfold table, Pearson's correlation, and binary logistic regression. Results: The intestinal barrier dysfunction was more likely to occur in the chronic liver disease group than that of non-hepatic disease group [54.15% (379/741) vs. 18.53% (139/750), χ (2) = 193.58, P < 0.001]. The correlation analysis between biochemical indicators of liver function and intestinal barrier function in chronic liver disease group showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), and total bilirubin levels were more susceptible to intestinal barrier dysfunction than those with normal indexes (P < 0.05 ). GGT had stimulated DAO (P < 0.05, OR > 1), D-lactate (P < 0.05, OR > 1), lipopolysaccharide (P < 0.05, OR > 1), ALT and AST. Conclusion: Chronic liver disease increases with damage to intestinal barrier function.

[Spatial-temporal analysis on pulmonary tuberculosis in Beijing during 2005-2015]

Objective: To analyze the spatial distribution and identify the high risk areas of pulmonary tuberculosis at the township level in Beijing during 2005-2015. Methods: Data on pulmonary tuberculosis cases was collected from the tuberculosis information management system. Global autocorrelation analysis, local indicators of spatial association and Kulldorff's Scan Statistics were applied to map the spatial distribution and detect the space-time clusters of the pulmonary tuberculosis cases during 2005-2015. Results: Spatial analysis on the incidence of pulmonary tuberculosis at the township level demonstrated that the spatial autocorrelation was positive during the study period. The values of Moran's I ranged from 0.224 3 to 0.291 8 with all the P values less than 0.05. Hotspots were primarily distributed in 8 towns/streets as follows: Junzhuang, Wangping, Yongding and Tanzhesi in Mentougou district, Yancun in Fangshan district, Wangzuo town in Fengtai district, Tianqiao street in Xicheng district and Tianzhu town in Shunyi district. Spatiotemporal clusters across the entire study period were identified by using Kulldorff's spatiotemporal scan statistic. The primary cluster was located in Chaoyang and Shunyi districts, including 17 towns/streets, as follows: Cuigezhuang, Maizidian, Dongfeng, Taiyanggong, Zuojiazhuang, Hepingjie, Xiaoguan, Xiangheyuan, Dongba, Jiangtai, Wangjing, Jinzhan, Jiuxianqiao, Laiguangying, Sunhe towns/streets in Chaoyang district, Houshayu and Tianzhu town in Shunyi district, during January to December 2005. Conclusion: Incidence rates of pulmonary tuberculosis displayed spatial and temporal clusterings at the township level in Beijing during 2005-2015, with high risk areas relatively concentrated in the central and southern parts of Beijing.

[Influence of gut microecology on the pathogenesis and treatment of nonalcoholic fatty liver disease]

OBJECTIVE

To establish a rat model of nonalcoholic fatty liver disease (NAFLD) using high-fat diet, and to dynamically observe the influence of the changes in gut microbiota on the development and progression of NAFLD in rats during and after modeling.

METHODS

Sprague-Dawley rats were given high-fat diet to establish the model of NAFLD, and these rats were randomly divided into high-fat group, antibiotic pretreatment group, antibiotic treatment group, restricted diet group, and control group. The rats were sacrificed in different feeding periods, and 16sRNA fluorescent quantitative PCR was used to analyze the changes in ileocecal microbiota in rats. The liver pathological scores were determined, and enzymatic colorimetry was used to measure blood lipid level in serum and liver homogenate. The sample mean t-test was used for comparison between groups.

RESULTS

Compared with the high-fat group, the restricted diet group showed the most significant improvements in quality of life and biochemical parameters. In the restricted diet group, the number of probiotics (Bifidobacterium and Lactobacillus) at the end of the ileum gradually increased and tended to increase over the time of intervention, and the most significant difference between this group and the high-fat group occurred at the 10th week (Bifidobacterium: 0.91±0.23 vs 0.28±0.12, P < 0.05; Lactobacillus: 0.78±0.04 vs 0.21±0.03, P < 0.05), while the number of enterococci decreased. There were no significant differences in enteric bacilli between groups (all P > 0.05). At the 10th week, the liver pathological scores in the control group, antibiotic treatment group, and restricted diet group were 1.13±1.74, 4.86±0.86, and 2.94±1.91, respectively, significantly lower than 7.09±2.03 in the high fat group (all P < 0.05).

CONCLUSION

Diet structure change and antibiotic intervention can adjust gut microecology, alleviate the lesions of NAFLD, and thus provide new strategies for the prevention and treatment of NAFLD from the perspective of microecology.

Non-HDL-cholesterol to HDL-cholesterol ratio as an independent risk factor for the development of chronic kidney disease

BACKGROUND AND AIMS

Dyslipidemia contributes to the development and progression of renal disease. The objective of this study was to investigate whether an elevated non-HDL-cholesterol to HDL-cholesterol ratio (NonHDLc/HDLc) predicts new-onset chronic kidney disease (CKD).

METHODS AND RESULTS

We followed 1891 Chinese adults with normal or near-normal kidney function at baseline who participated in an annual health checkup program for the occurrence of new-onset CKD [defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m(2) (low eGFR) and/or proteinuria (defined as urinary protein ≥1 + on dipstick testing)] or low eGFR. Cox proportional hazards models were used to examine the independent relationship between the plasma NonHDLc/HDLc ratio and new-onset CKD. During a median follow-up period of 2.8 years, 3% (n = 57) of participants developed new-onset CKD. Compared with patients in the lowest tertile, patients with NonHDLc/HDLc ratios in the highest tertile had a 1.45-fold higher risk of new-onset CKD (hazard ratio [HR], 2.45; 95% confidence interval [95% CI], 1.07 to 5.61; P = 0.035) after adjustment for potential confounders. There was a marginally significant association with low eGFR (tertile 3 versus tertile 1: HR, 2.94; 95% CI, 0.98 to 8.82; P = 0.054).

CONCLUSIONS

NonHDLc/HDLc ratio is an independent risk factor for the development of CKD. Assessment of NonHDLc/HDLc ratio may help identify high risk groups with chronic kidney disease.

DNA topoisomerase II as the primary cellular target for salvicine in Saccharomyces cerevisiae

AIM

To identify whether DNA topoisomerase II (Topo II) is the primary cellular target of salvicine in Saccharomyces cerevisiae (S cerevisiae) and the action mode of salvicine.

METHODS

The catalytic activity of Topo II was determined by Topo II mediated supercoiled pBR322 relaxation. The effects of salvicine on the growth of four strains of S cerevisiae were assessed by clone forming assay.

RESULTS

Salvicine inhibited Topo II mediated supercoiled pBR322 relaxation in cell-free system. Cytotoxicities of salvicine to parent (JN394) and TOP1 deleted (JN394top1-) yeast cells were at the same level, suggesting Topo I might not be the cellular target of salvicine. Salvicine displayed high activity against JN394t2-1 cells at 25 degrees C, while no growth inhibition was observed at 30 degrees C in the concentration range of interest. Furthermore, JN394t2-5 cells which expressed top2-5 mutant allele were highly resistant to salvicine and etoposide (VP16).

CONCLUSION

Topo II was the primary cellular target of salvicine in vivo and salvicine killed yeast cells mainly by trapping the DNA-Topo II cleavage complex. Salvicine and VP16 might share some similar action locus on Topo II.

[Detection of microbes adherent to particles in a closed environment]

OBJECTIVE

In order to provide reference for controlling and monitoring the environmental contamination in the spacecraft, the species and amount of microbes, which adhere to the suspended particles with different size in a closed environment were detected.

METHOD

According to USA EPA IP-10, particles were continuously sampled by an impactor in a closed environment. The particles were divided into three grades by their aerodynamic diameters (AD): 100 micrometers > or = AD > 10 micrometers, 10 micrometers > or = AD>2 micrometers and AD < or = 2 micrometers. Clean outdoor air was collected as control by the same way. The collected particles were precisely weighed. The microbes that adhere to the particles were cultivated, counted and identified.

RESULT

By calculating total suspended particles (TSP) and inhalant particles (IP) of the closed environment, counting, clarifying and identifying the microbes, 6 kinds of bacteria, 2 genus of actinomyces and 6 kinds of fungi that adhere to the particles were detected.

CONCLUSION

The particles in a closed environment may have some effect on human health and instruments.

A novel case of unilateral blepharophimosis syndrome and mental retardation associated with de novo trisomy for chromosome 3q

We have evaluated a 3 2/12 year old girl who presented with unilateral blepharophimosis, ptosis of the eyelid, and mental retardation. Additional dysmorphic features include microcephaly, high, narrow forehead, short stubby fingers, and adduction of the right first toe. Cytogenetic analysis showed an unbalanced karyotype consisting of 46,XX,add(7)(q+) that was de novo in origin. Fluorescence in situ hybridisation (FISH) using microdissected library probe pools from chromosomes 1,2,3,7, and 3q26-qter showed that the additional material on 7q was derived from the distal end of the long arm of chromosome 3. Our results indicate that the patient had an unbalanced translocation, 46,XX,der(7)t(3;7)(q26-qter;q+) which resulted in trisomy for distal 3q. All currently reported cases of BPES (blepharophimosis-ptosis-epicanthus inversus syndrome) with associated cytogenetic abnormalities show interstitial deletions or balanced translocations involving 3q22-q23 or 3p25.3. Our patient shares similar features to BPES, except for the unilateral ptosis and absence of epicanthus inversus. It is possible that our patient has a contiguous gene defect including at least one locus for a type of blepharophimosis, further suggesting that multiple loci exist for eyelid development.

Genetic differences in alcohol drinking preference between inbred strains of mice

Genetic factors are known to influence the preference for drinking alcohol-in humans as well as certain inbred strains of laboratory animals. Here we examined the possible role of the aromatic hydrocarbon receptor (AHR) in alcohol-preferring C57BL/6J (B6, high-affinity AHR) and alcohol-avoiding DBA/2J (D2, low-affinity AHR) inbred mouse strains, and in the two congenic lines B6.D2-Ahrd (> 99% B6 genome with the D2 low-affinity AHR) and D2.B6-Ahrb-1 (> 99% D2 genome with the B6 high-affinity AHR). This laboratory had previously shown an association between resistance to intraperitoneal ethanol-induced toxicity and the high-affinity AHR. Offering the choice between drinking water and 10% ethanol, we found that alcohol preference is three- to four-fold greater in B6 than D2 mice, as well as three- to four-fold greater in B6.D2-Ahrd than D2.B6-Ahrb-1 mice-indicating that alcohol preference is AHR-independent. The prototype AHR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; dioxin) did not affect the rates of chronic alcohol consumption in B6 or D2 mice, suggesting that dioxin-inducible metabolism does not play a major role in alcohol drinking preference. In B6 mice, we found that oral treatment with the aldehyde dehydrogenase (ALDH) inhibitor disulfiram decreased alcohol preference by 50%, whereas oral treatment of the catalase inhibitor 3-amino-1,2,4-triazole increased alcohol drinking preference by 15-20%. Although liver and brain ALDH activities were both significantly higher in D2 than B6, these activities were not related to alcohol consumption. Hepatic and brain catalase activities, on the other hand, were two- to three-fold higher in D2 and D2.B6-Ahrb-1 mice, compared with that in B6 and B6.D2-Ahrd. Furthermore, brain acetaldehyde levels were inversely related to the quantity of alcohol voluntarily consumed. We conclude that the alcohol drinking preference between the B6 and D2 inbred mouse strains is independent of the Ah receptor-but is genetically determined, in part, by the level of brain catalase activity which, in turn, regulates brain acetaldehyde concentrations.

Sequencing for 4 single-copy DNA segments from human chromosome 8q24.1

A successful method for constructing human chromosome 8q24.1 band specific probe pool by microdissection and microcloning is described in this paper. The probe pool was proved to be band-specific by fluorescence in situ hybridization. Through Southern blot analysis, 34 single copy DNA segments were obtained and four of them were sequenced. It is possible to provide useful landmarks for constructing human chromosome 8q24.1 physical map and STSs map.

Microdissection of human high resolution banded chromosome, polymerase chain reaction and microcloning

A simple technique for microdissection of specific region of human high resolution banded chromosome, followed by polymerase chain reaction (PCR), and microcloning was successfully used to microdissect 4 chromosomal pieces from the distal one third from band 11.2 to the terminal of the short arm of Y chromosome where the testis determining factor is located; 3.6 x 10(4) clones were obtained after 30 cycles of PCR. We analysed 41 clones with insert. The size of insert ranges from 140 to 350 bp (average 250 bp). A Southern blot analysis was done for one of them, and a 2.5 kb Hind III fragment was detected.

Synaptic reorganization in the hippocampus induced by abnormal functional activity

Abnormal functional activity induces long-lasting physiological alterations in neural pathways that may play a role in the development of epilepsy. The cellular mechanisms of these alterations are not well understood. One hypothesis is that abnormal activity causes structural reorganization of neural pathways and promotes epileptogenesis. This report provides morphological evidence that synchronous perforant path activation and kindling of limbic pathways induce axonal growth and synaptic reorganization in the hippocampus, in the absence of overt morphological damage. The results show a previously unrecognized anatomic plasticity associated with synchronous activity and development of epileptic seizures in neural pathways.

Cytogenetic and biological characterization of two new human plasma cell lines

Two new human plasma cell lines designated as ACB-885 and ACB-1085 have been established from a 39-year-old patient with multiple myeloma. These cell lines have definitive plasma cell features by morphologic examination, and essentially all of the cells are positive for cytoplasmic IgG kappa immunoglobulin. These cells are negative for standard T-cell surface markers and mature B-cell markers, such as B1, B2, and HLA-DR, but are strongly positive for the antigen defined by OKT-10. The cells are negative for Epstein-Barr virus. The cell lines have a doubling time of 30-35 hours and a growth fraction approaching 100%. Cytogenetic analysis showed a 2n chromosome number of 45-46 with very similar karyotypic abnormalities in both the plasma cell lines and the original tumor material. One of the chromosomes in each of the pairs of chromosomes number #1, #2, #6, #7, #8, #10, #12, #13, and #22 were consistently missing. These were replaced by eight marker chromosomes that resulted from chromosomal rearrangements involving mainly these missing chromosomes. Almost all of the breakpoints occurring in the marker chromosomes were identified, and eight of these breakpoints have been reported in other studies of myeloma plasma cells. Homogeneously staining regions were observed in two marker chromosomes suggesting gene amplification in these chromosomal regions.