[Clinical characteristics and prognosis of 28 cases of infant acute lymphoblastic leukemia]

Objective: To analyze the clinical characteristics and prognosis of patients with infant acute lymphoblastic leukemia (IALL). Methods: A retrospective cohort study.Clinical data, treatment and prognosis of 28 cases of IALL who have been treated at Beijing Children's Hospital, Capital Medical University and Baoding Children's Hospital from October 2013 to May 2023 were analyzed retrospectively. Based on the results of fluorescence in situ hybridization (FISH), all patients were divided into KMT2A gene rearrangement (KMT2A-R) positive group and KMT2A-R negative group. The prognosis of two groups were compared. Kaplan-Meier method and Log-Rank test were used to analyze the survival of the patients. Results: Among 28 cases of IALL, there were 10 males and 18 females, with the onset age of 10.9 (9.4,11.8) months. In terms of immune classification, 25 cases were B-ALL (89%), while the remaining 3 cases were T-ALL (11%). Most infant B-ALL showed pro-B lymphocyte phenotype (16/25,64%). A total of 22 cases (79%) obtained chromosome karyotype results, of which 7 were normal karyotypes, no complex karyotypes and 15 were abnormal karyotypes were found. Among abnormal karyotypes, there were 4 cases of t (9; 11), 2 cases of t (4; 11), 2 cases of t (11; 19), 1 case of t (1; 11) and 6 cases of other abnormal karyotypes. A total of 19 cases (68%) were positive for KMT2A-R detected by FISH. The KMT2A fusion gene was detected by real-time PCR in 16 cases (57%). A total of 24 patients completed standardized induction chemotherapy and were able to undergo efficacy evaluation, 23 cases (96%) achieved complete remission through induction chemotherapy, 4 cases (17%) died of relapse. The 5-year event free survival rate (EFS) was (46±13)%, and the 5-year overall survival rate (OS) was (73±10)%.The survival time was 31.3 (3.3, 62.5) months. There was no significant statistical difference in 5-year EFS ((46±14)% vs. (61±18)%) and 5-year OS ((64±13)% vs. (86±13)%) between the KMT2A-R positive group (15 cases) and the KMT2A-R negative group (9 cases) (χ2=1.88, 1.47, P=0.170, 0.224). Conclusions: Most IALL patients were accompanied by KMT2A-R. They had poor tolerance to traditional chemotherapy, the relapse rate during treatment was high and the prognosis was poor.

[Evaluation of the effect of comprehensive prevention and management of diabetes mellitus of two cross-sectional surveys based on community population]

To investigate the prevalence of diabetes mellitus (DM) among residents in Chongchuan district, Nantong city in 2012 and 2018, and evaluate the effectiveness of community comprehensive management of DM. Based on the data of 17 780 and 13 382 residents in the cross-sectional surveys of the " National Demonstration Area for Comprehensive Prevention and Control of Chronic Diseases " project in Chongchuan District of Nantong City, Jiangsu Province in 2012 and 2018, 4 583 and 3 996 DM-related information were obtained. The population of Jiangsu Province in 2012 and 2018 was used as the reference for standardization. The rates of prevalence and management (including awareness, treatment, treatment of patients who knew their diabetic situation, control and control of patients under treatment) of DM in the two surveys were compared using chi-square test. The results showed that in 2012 and 2018, the prevalence rates of DM were 12.0% and 15.7% (χ²=24.25, P<0.05), and the standardized rates were 10.1% and 10.8% (χ²=1.05, P=0.306). The incidence rates were 5.7% and 2.3%, respectively (χ²=55.60, P<0.05). The standardized prevalence rates in the two surveys were 9.7% and 11.6% for males (χ²=3.66, P=0.056) and 10.5% and 9.9% for females (χ²=0.50, P=0.481), 7.2% and 6.5% (χ²=0.85, P=0.357) for people aged 18-59 years old and 20.6% and 21.9% (χ²=0.91, P=0.339) for people aged 60 years and over, respectively. The standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, control, and control of patients under treatment in 2018 were 84.4%, 80.3%, 95.2%, 58.4%, and 70.2%, respectively, higher than 47.2%, 23.4%, 44.8%, 30.4% and 59.4% in 2012 (χ²=183.33, χ²=380.65, χ²=282.99, χ²=93.24, χ²=6.22, all P<0.05). Among men, the standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, and control in 2018 were 85.8%, 78.8%, 91.8% and 62.7%, higher than 50.5%, 37.5%, 72.3% and 32.6% in 2012 (χ²=78.40, χ²=96.17, χ²=27.55, χ²=48.96, all P<0.05). Similarly, the standardized management rates in 2018 were 83.0%, 81.7%, 98.5%, 54.1% and 65.1%, higher than 44.0%, 10.0%, 18.3%, 28.2% and 48.8% in 2012 among women (χ²=105.52, χ²=326.36, χ²=317.22, χ²=43.34, χ²=3.87, all P<0.05). The standardized rates of awareness, treatment, treatment of patients who knew their diabetic situation, and control of people aged 18-59 and 60 years and over were 82.9%, 79.7%, 96.1%, 55.0% and 88.0%, 81.8%, 93.0% and 67.2%, higher than 42.6%, 19.8%, 42.2%, 27.5% and 63.9%, 36.8%, 53.9%, 40.8% in 2012 (χ²=44.51, χ²=102.17, χ²=57.78, χ²=21.65, all P<0.05; χ²=71.18, χ²=181.55, χ²=146.26, χ²=59.23, all P<0.05). The comprehensive prevention and control system of chronic diseases, which comprehensively covered the life of community residents, had good management effect on DM, and effectively promoted health education and health promotion.

[Clinical application of LASEREO endoscopic system in early gastric cancer]

Objective: To evaluate the clinical application of LASEREO endoscopic system in early gastric cancer (EGC). Methods: A total of 68 patients diagnosed with EGC were retrospectively analyzed between August 2017 to December 2020 in Fuding Hospital Affiliated to Fujian University of Traditional Chinese Medicine. There were 50 males and 18 females finally enrolled with a median age of 64 years. EGCs were analyzed from subjective and objective aspect, as well as from magnification and non-magnification status. Six endoscopists evaluated the visibility of the EGC (RSC) and calculated the color difference (ΔEC) between EGC and the surrounding mucosa in white light imaging (WLI), blue light imaging-bright (BLI-Bri) and linked color imaging (LCI) modes. In the case of magnification (×80), the visibility of the microstructures and microvessels (RSV) was analyzed and the color difference (ΔEV) between microvessels and non-vessels areas were calculated in WLI, BLI and LCI modes. The visibility was evaluated using visibility ranking scale(RS) and the color difference (ΔE) was calculated using L*a*b* color space. Results: In WLI, BLI-Bri, and LCI modes, the mean (±SD) RSC were 2.56±0.68, 2.63±0.59 and 3.17±0.50, and the mean(±SD) ΔEC were 15.71±5.58, 12.04±3.73, and 22.84±8.46, respectively, which in LCI were higher than those in WLI and BLI-Bri modes (P<0.001).Regarding the data evaluated by senior endoscopists, the RSC was higher in BLI-Bri than that in WLI mode (2.98±0.58 vs. 2.79±0.73, P<0.001), but as to those evaluated by junior endoscopists, there were no significant differences between the WLI and BLI-Bri modes(2.29±0.72 vs. 2.23±0.72,P =0.218).In magnifying endoscopy with WLI, BLI, and LCI modes, the mean(±SD) RSV were 2.95±0.28, 3.46±0.40, and 3.38±0.33, and the mean (±SD) ΔEV were 21.68±7.52, 44.29±10.94, and 45.38±14.29, respectively.The RSV and ΔEV in LCI and BLI were higher than that in WLI mode (P<0.001). Conclusions: LCI improves the visibility of EGC by increasing ΔEC, especially in junior endoscopists. Both BLI and LCI improve the visibility of microstructures and microvessels under magnification.

[Exploring the teaching mode about clinical laboratory diagnostic pathway for chronic hepatitis B]

Exploring a new teaching mode of CHB laboratory diagnostics to improve the teaching quality through establishment a teaching model covered the whole process of CHB disease diagnosis and differential diagnosis, treatment, drug selection, the toxicity and side effects prediction, effect monitoring, and prognosis evaluation. According to the CHB clinical diagnosis and treatment guidelines, formulated the laboratory examination and detection strategies related to different stages of CHB, and established CHB clinical laboratory diagnostic pathway. Compared the classroom teaching effect by the questionnaire between the 2016 and 2017 eight-year undergraduates from the First Clinical College of Wuhan University. In this study,the CHB clinical laboratory diagnostic pathway was established and approved by clinicians, which covered the whole process of CHB disease diagnosis and differential diagnosis, treatment, drug selection, the toxicity and side effects prediction, effect monitoring, and prognosis evaluation. The teaching quality evaluation indicators and the scores on the class test had been greatly improved with the clinical diagnostic pathway teaching mode in the classroom teaching of 2017 clinical medicine undergraduates compared with the traditional teaching mode in the 2016 clinical medicine undergraduates. In summary, the medical students not only could realize the organic integration of laboratory diagnostics and clinical medicine, but also improves overall understanding of various laboratory tests in CHB diagnosis and treatment from the teaching model of laboratory diagnostics based on the CHB clinical laboratory diagnostic pathway,and the quality of teaching for CHB has been significantly improved.

A rapid detection of tomato yellow leaf curl virus using recombinase polymerase amplification-lateral flow dipstick assay

Tomato yellow leaf curl disease which is caused by Tomato yellow leaf curl virus (TYLCV) is economically important and a widely spread tomato disease in China. Rapid and accurate detection methods are important in the control TYLCV. Here, a rapid method was developed to identify TYLCV on the basis of recombinase polymerase amplification (RPA) that can be visualized in 5 min using lateral flow dipsticks. The sensitivity and the specificity of this method were evaluated. This method can detect 0·5 pg DNA after 30 min at 37°C without any expensive instrumentation. In addition, it showed higher sensitivity than a PCR method when purified DNA was used. Moreover, the TYLCV was specifically detected, whereas other viruses infecting tomato produced negative results. The crude tomato extracts used in this assay has potential application in minimally equipped plant clinic laboratories. This method will facilitate the early and rapid detection of TYLCV for the timely application of control measures.

[Clinical characteristics and gene expression profiles in children with ETV6-RUNX1 acute lymphoblastic leukemia]

目的

通过基因表达谱研究儿童ETV6-RUNX1阳性急性淋巴细胞白血病（ALL）异质性，探索不同聚类分组临床特征，为临床个性化诊疗及利用测序技术探索预后相对不良组预测模型提供可行性参考。

方法

应用改进的基因片段分析技术对2016年8月至2019年6月北京儿童医院收治的264例初诊ALL患儿的骨髓标本进行57个分型基因检测和聚类分析，重点分析56例ETV6-RUNX1阳性患者的基因表达谱与临床特点、免疫表型和早期化疗反应的关系。

结果

基因分型聚类显示ETV6-RUNX1阳性ALL被分为两组：E/R-1组（45例，80.4%）和E/R-2组（11例，19.6%）。E/R-2聚类离散度大于E/R-1，spearman相关系数分别为0.788、0.901；E/R-2、E/R-1组初诊PLT中位数分别为104（27～644）×10⁹/L、50（8～390）×10⁹/L（P<0.01），初诊骨髓原始幼稚细胞比例分别为0.830（0.270～0.975）、0.935（0.445～0.990）（P<0.05）；CD22⁺CD34⁺CD20⁻CD117⁻CD56⁻免疫组合在E/R-2组占比更高（P<0.001）；E/R-2和E/R-1组化疗第33天流式细胞术检测的微小残留病（MRD）转阴例数分别为5例（55.6%）和32例（88.9%）（P＝0.064），去除临界值病例敏感性分析转阴例数分别为5例（55.6%）和32例（91.4%）（P＝0.035）；第33天PCR检测的MRD转阴例数分别为7例（77.8%）和36例（100.0%）（P＝0.047）。

结论

ETV6-RUNX1阳性ALL患儿在基因表达谱层面存在异质性，符合E/R-2表达特征的患儿可能初诊时血小板减少倾向小但早期化疗反应相对不良。

[Study on the correlation between dietary N-glycolylneuraminic acid intake and chronic inflammation state of body]

Objective: To explore the correlation between dietary N-glycolylneuraminic acid (Neu5Gc) intake and chronic inflammation state of body. Methods: A total of 306 samples of 102 types of food were purchased from a supermarket in Xiamen in September 2019, including grains, meat, poultry, seafood, eggs, beans, dairy products, vegetables and fruits. The content of Neu5Gc in food was determined by liquid chromatography-mass spectrometry. A total of 500 healthy freshmen from Xiamen University were selected by using a simple random sampling method. The food frequency questionnaire was used to investigate the food intake in the past year. The food intake was corrected by 3 consecutive 24-hour recalls, and the amount of Neu5Gc intake was calculated. The concentration of anti-Neu5Gc antibody, C-reactive protein (CRP) and interleukin-6 (IL-6) in serum was detected. Spearman correlation analysis was used to explore the correlation between Neu5Gc intake and anti-Neu5Gc antibody, CRP and IL-6 levels. Results: Neu5Gc was mainly found in red meat and liquid dairy products. The contents of Neu5Gc in beef, lamb and pork were (30.32±2.84), (20.39±4.73) and (5.58±1.04) mg/kg, respectively, and in liquid milk and yogurt were (10.87±1.54) and (6.91±0.24) mg/L, respectively. The M (P₂₅, P₇₅) intake of Neu5Gc for all participants was 4.62 (2.20, 8.60) mg/d. The M(P₂₅, P₇₅) intake of Neu5Gc for males about 6.60(2.83, 10.20) was higher than that for females about [3.84 (1.84, 6.35) mg/d] (P<0.001). The M (P₂₅, P₇₅) of serum anti-Neu5Gc, CRP and IL-6 levels were 3.07 (2.17, 4.14) μg/ml, 0.37 (0.22, 0.87) mg/ml and 61.82 (12.23, 315.30) pg/ml, respectively. Spearman correlation analysis showed that the intake level of Neu5Gc was positively correlated with serum anti-Neu5Gc antibody, CRP and IL-6 levels, with r_s values about 0.222, 0.102 and 0.126, respectively (all P values <0.05). Conclusion: Dietary Neu5Gc intake is mainly from red meat and liquid dairy products, and its intake level is positively correlated with chronic inflammatory state of body.

[Preliminary study on the elimination of artifacts of five kinds of dental prosthetic materials by energy spectrum CT multi-material artifact reduction technology]

Objective: To investigate the effect of the multi-material artifact reduction (MMAR) algorithm of spectral CT in reducing the beam hardening artifacts in dental restoration material. Methods: Three-unit fixed bridge restorations were fabricated on the first to third molars in pig jaw. Gold alloy, zirconia, cobalt chromium alloy, nickel chromium alloy and pure titanium were used as materials for these fixed bridges. After restoration delivery, the pig jaw was scaned using energy spectrum CT machines. Images in regular 120 kVp scan mode were used as conventional group, and reconstructed single-energy horizontal images of 80, 90, 100, 110, 120, 130 and 140 keV in energy spectrum scanning mode were used as energy spectrum group, and reconstructed images applied MMAR technology in energy spectrum scanning mode were used as energy spectrum MMAR group. Each group was scanned 10 times to measure CT value and noise of muscles around dental prosthetic materials and adjacent non-artifact layers. Artifact index was calculated. Two radiologists scored the image quality of each group subjectively. Kruskal Wallis rank sum test was used to compare the difference of image noise, artifact index and subjective score among the control group and the best keV condition in the energy spectrum group and the energy spectrum MMAR group. Results: The image noise of energy spectrum group and energy spectrum MMAR group decreased gradually with the increase of single energy level. The artifact index of pure titanium restorations in conventional group, energy spectrum group and energy spectrum MMAR group were 71.0±8.0, 21.4±2.7 and 14.7±2.7 respectively, and these values were significantly lower than those of other materials in the same group (P<0.05). The subjective image quality scores in energy spectrum MMAR group were as follows: 3.0±0.2 for gold alloy, 4.3±0.5 for zirconia, 3.0±0.4 for cobalt chromium alloy, 3.1±0.4 for cobalt chromium alloy, and 4.6±0.5 for pure titanium. These scores were significantly smaller than those in the conventional group (P<0.05). There was no significant difference in noise between energy spectrum group and energy spectrum MMAR group (P>0.05), and the noise values in energy spectrum group and energy spectrum MMAR group were significantly lower than that in the conventional group (P<0.05). Conclusions: Artifacts of pure titanium is minimal. Energy spectrum CT combined with MMAR technology can effectively reduce the artifacts of gold, zirconia, cobalt-chromium alloy, nickel-titanium alloy and pure titanium. This technique can be used as an effective method to remove artifacts of dental prosthesis.

Local dermal application of a compound lidocaine cream in pain management of cancer wounds

The aim of this study was to explore the analgesic effect of local application of compound lidocaine/prilocaine cream on cancer wounds during wound care in order to reduce the amount of morphine intake or completely replace the systemic morphine administration and optimize the protocol for cancer wound pain management. All patients were enrolled with a visual analog scale (VAS) pain score ≥4. Before wound care, 60 patients were randomly divided into 2 groups of 30 each: morphine group (10 mg tablet); topical 5% compound lidocaine cream group (0.2 g/cm²). VAS scores, heart rate, and Kolcaba comfort level were recorded for the two groups 10 min before and 10, 15, 20, and 25 min after wound care and data were analyzed statistically. The means for the pain score and heart rate of the topical lidocaine/prilocaine cream group were lower than those of the morphine group (P<0.01) and the Kolcaba comfort level was higher (P<0.01). Local dermal application of the compound lidocaine cream can be used as an alternative to the systemic morphine administration in cancer wound care for its safety and effectiveness. In addition, it can improve the patients' comfort and quality of life.

PM2.5 stimulated the release of cytokines from BEAS-2B cells through activation of IKK/NF-κB pathway

Previous studies indicated that exposure to fine particulate matter (PM_2.5) was related to pulmonary inflammatory diseases through activation of nuclear factor kappa B (NF-κB) signaling pathway to trigger cytokine secretions in human lung carcinoma cells. To investigate the potential mechanisms underlying expression of cytokines via activated NF-κB by PM_2.5, human bronchial epithelial cells (BEAS-2B cells) were treated with PM_2.5 extracts at different concentrations (6, 13, 25, 50, 100, 200, and 400 µg mL^-1) for 6 and 24 h. We found that 100 µg mL^-1 PM_2.5 increased interleukin 6 (IL-6) and IL-8 expression at 24 h (p < 0.05 or p < 0.01). Moreover, 100 µg mL^-1 PM_2.5 upregulated phosphorylated IκB kinase (IKK), p65, and IκBα at 6 h, which could be reversed by the IKK inhibitor Bay11-7082 (p < 0.05 or p < 0.01). The p65 subunit of NF-κB was translocated into the nucleus of the cells treated with 100 µg mL^-1 PM_2.5 at 6 and 24 h. Bay11-7082 partly inhibited PM_2.5-induced increases of IL-6 and IL-8 secretion. The results indicated that PM_2.5 extract increased IL-6 and IL-8 levels in BEAS-2B cells through activation of IKK/NF-κB pathway. Our study will contribute to better understanding of the mechanism of PM_2.5-induced pulmonary inflammatory diseases.

[Effects of casein phosphopeptide-amorphic calcium phosphate on enamel erosion: an in situ study]

Objective: To evaluate the effects of casein phosphopeptide-amorphic calcium phosphate (CPP-ACP) on enamel erosion using an improved in situ experimental protocol. Methods: Forty-eight enamel blocks were prepared from fresh-extracted human premolars and further embedded in the acrylic resins. The present study was divided into 2 parts. In part 1 of the study, two volunteers were recruited to test the availability and safety of the in situ erosion protocol. Customized intraoral appliance was made with 4 reservoirs containing the specimens for each volunteer. For each intraoral applicance, 2 reservoirs were made with the openings and the other 2 remained intact. All volunteers were instructed to drink 150 ml cola within 5 min using the gargling method after placing appliances intraorally for 2 h. After erosion, the appliances were remained undisturbed intraorally for 1 h until the next erosive attack. The in situ erosion cycles were performed 4 times daily over 7 d. In part 2 of the study, forty specimens were randomly divided into 2 groups (n=20): CPP-ACP group and control group. The surfaces of specimens in CPP-ACP group were pretreated with CPP-ACP for 3 min before in situ erosion, whereas the specimens in control group were pretreated with deionized water for 3 min. For each intraoral applicance, 4 reservoirs were made with openings. Ten healthy volunteers were recruited and the above-mentioned in situ erosion protocol was applied to test the effects of CPP-ACP on enamel erosion. The surface microhardness and surface microstructure of the samples were examined before and after erosion in both parts of the study. The data were statistically analyzed using ANOVA and LSD tests. Data were considered statistically significant at a level of P<0.05. Results: Significant surface softening was observed in all specimens after erosion (P<0.001). The surface microhardness in the CPP-ACP group and control group were (198.8±23.2) and (152.4±42.1) HV, respectively (P=0.040). The specimens in the CPP-ACP group showed significantly fewer changes in surface microstructure compared with those in the control group. Conclusions: Based on this in situ experimental protocol, short-time consuming of acid beverages would produce significant effects on the surface microhardness of the human enamel, whereas the application of CPP-ACP can increase the erosion resistance of the enamel.

[Characterization analysis of gM, gL genes of varicella zoster virus in six provinces of China]

Objective: To analyze the genetic characterization of glycoprotein M(gM.),glycoprotein L(gL) of varicella zoster virus. Methods: According to the program of "Ministry of Science and Technology of China" , Based on the 12 suspected VZV patients monitored in Beijing (1 case), Shanghai (5 cases), Jilin (2 cases), Qinghai (1 case), Guangdong (2 case) and Sichuan (case) in 2007-2015. A total of 12 Vesicle fluid and throat swab samples were collected. Positive samples were identified by Agarose gel electrophoresis and two glycoprotein genes were amplified by polymerase chain reaction (PCR). Nucleotide sequences were determined and analyzed by PCR amplification of VZV positive specimens V-OKA-BK of the domestic varicella attenuated live vaccine and the Varilrix-1 of the imported attenuated live vaccine. Nucleotide sequences of VZV positive specimens, vaccine strains (V-OKA-BK, varilrix-1) and GenBank foreign wild strains (41 strains), parent strains (P-oka), vaccine strains (V-oka, Varilrix, Varivax) were compared using BioEdit and MEGA 5.0. Results: 12 specimens were VZV positive. Compared with the vaccine strains and the parent strains, the GM gene of 1 positive specimen had radical mutation at 86686 sites, which resulted in amino acid mutation, 5 positive specimens had base mutation at 87844 sites, and 30 strains of foreign wild strains had the same variation at 87 844 sites. 1 positive specimens of gL gene in 101245 sites had base mutation, and led to amino acid mutation, 6 positive specimens at 101624, 101625, 101626 sites had base of loss and the foreign wild strains in these 3 sites had the same variation. Compared with the vaccine strains, the nucleotide and amino acid homology of gM of 12 VZV positive specimens were 99.2%-100% and 98.2%-100%, respectively, and gL of those were 99.3%-100% and 98.6%-100%, respectively. Compared with 41 strains of foreign wild strains, homology of gM's nucleotides and amino acid were 99.3%-100% and 98.5%-100%, respectively; 99.1%-100% and 98.6%-100% for gL. The results of phylogenetic analysis showed that 7 VZV positive samples were on the same branch with 4 vaccine strains and p-oka strain. Based on gL, 12 VZV positive samples were on the same branch as the vaccine strains and p-oka strain. Conclusion: This study demonstrates that the genes of gM, gL are highly conserved and remain stable immunogen, which may be involved in the attenuation of VZV and need to be further researched.

[Epidemiological characteristics of Coxsackie virus A16 caused hand foot and mouth disease cases in Guangdong province, 2012-2016]

Objective: To analyze the epidemiological characteristics of hand foot and mouth disease (HFMD) cases caused by Coxsackie virus A16 (Cox A16) in Guangdong province from 2012 to 2016. Methods: The data of mild HFMD cases caused by Cox A16 were collected from 8 sentinel hospitals in 8 prefecture-level cities in Guangdong to estimate Cox A16 infection status and its population and time distribution characteristics. Results: (1) The highest estimated incidence of Cox A16 infection was in 2014 (113.0/100 000), followed by 2016 (86.4/100 000) and 2012 (79.1/100 000), while the estimated incidence was lower in 2015 (29.0/100 000) and 2013 (28.8/100 000). (2) Cox A16 was confirmed to be the predominant pathogen causing HFMD outbreaks (54.6%, 89/163). The number of outbreaks in the year with high incidence (28 outbreaks) was 11.2 times higher than that in the year with low incidence (2.5 outbreaks). (3) Across all age groups, the annual estimated incidence of Cox A16 infection decreased with age (trend χ(2)=853 905.63, P<0.01). The incidence was highest in age group 1 year (1 449.2/100 000), followed by that in age group 3 years (1 097.0/100 000), in age group 2 years (1 083.5/100 000), in age group 4 years (687.8/100 000) and in age group 0 year (604.9/100 000). Among the age groups <12 months, the estimated incidence increased with age (trend χ(2)=5 541.77, P<0.01), which was highest in age group 11-months (2 105.1/100 000), followed by that in age groups 10-months (1 448.6/100 000), 9-months (938.3/100 000), 8-months (703.3/100 000) and 6-months (664.6/100 000). (4) The annual incidence peak was during May (143.9/100 000)-June (131.5/100 000). Conclusion: The prevalence of Cox A16 infection differed with year in Guangdong during 2012-2016. When the incidence of Cox A16 infection was high, more outbreaks occurred. The prevalence occurred mainly in nurseries and kindergartens from May to June each year. Children aged 0-4 years were the high risk group for Cox A16 infection, children aged 6-11 months were at high risk for Cox A16 infection.

[The incidence and risk factors of catheter-related-thrombosis during induction chemotherapy in acute lymphocytic leukemia children]

目的

分析初诊急性淋巴细胞白血病（ALL）诱导化疗期外周静脉穿刺中心静脉置管（PICC）患儿导管相关性血栓（CRT）的危险因素。

方法

收集2014年3月1日至2014年12月31日首都医科大学附属北京儿童医院血液肿瘤中心白血病病房行PICC置管的116例初诊ALL患儿临床资料。

结果

①PICC置管后第15天33例（28.4%）患儿发生CRT（CRT组），83例患儿未发生CRT（非CRT组）。②两组在性别、年龄分布、ALL危险度、免疫表型以及置管时两组血常规、凝血功能、是否合并感染、置管静脉方面差异无统计学意义，CRT组右侧置管比例高于非CRT组[75.8%（25/33）对55.4%（46/83），P=0.043]。③CRT组患者均无临床症状，置管第15天D-二聚体高于非CRT组[0.18（0.05~2.45）mg/L对0.11（0.01~5.34）mg/L，P=0.001]。④观察期中出现3例导管相关性并发症，均为导管相关性感染，其中2例并发CRT。⑤置管第33天CRT组26例患者复查B超，19例（73.1%）血栓缩小，6例（23.1%）无明显变化，1例（3.8%）增大。

结论

CRT是初诊ALL患儿诱导化疗期PICC置管的常见导管相关并发症，但症状出现较少，大部分血栓可自行缩小，右侧置管为CRT发生的危险因素；检测D-二聚体水平以及定期进行导管部位B超检查有助于及时发现CRT。

[Clinical characteristics and prognosis in 12 patients with adult T cell leukemia/lymphoma confirmed by HTLV-1 provirus gene detection]

Objective: To analyze the clinical characteristics and prognosis of adult T cell leukemia/lymphoma (ATLL). Methods: Peripheral blood samples from patients who were suspected as ATLL from March, 2013 to July, 2015, were collected for HTLV-1 provirus genes detection in genomic DNA extraction by PCR. Cases showing positive results were confirmed as ATLL. Clinical and laboratory characteristics, therapeutic outcomes and survival evaluation were collected. Results: 12 out of 23 suspected patients were confirmedly diagnosed as ATLL through HTLV-1 provirus genes detection by PCR. Eight patients were male and four patients were female. Median age was 51 (range 28-66) years old. All of those patients came from coastal cities of Fujian province where a HTLV-1 epidemic area locates. In the subtype classification of these 12 ATLL, 11 patients were classified as acute type and one case as lymphoma type ATLL. As one of the clinical characteristics of ATLL, ' flower cells ', with typical or atypical morphology had been observed in a high rate (81.8%). Clinical symptom such as hepatomegaly, splenomegaly and lymphadenectasis were detected in most of patients, and hypercalcemia and elevated LDH were also noted commonly. The ATLL cells immunophenotype were typical, and the major subtype was CD4+ CD8- type. Confection of hepatitis B virus was detected in a high rate (54.5%). Ten patients received chemotherapy, and 2 cases in complete remission after chemotherapy received allogeneic hematopoietic stem cell transplantation. At the end of the follow-up, 7 cases died, 4 cases survived, 1 case was lost, and the median survival was 2.8 (0.9-10.8) months. We found a case had HTLV-1 provirus negative after transplantation. Conclusion: In the coastal area of Fujian Province, ATLL is not rare. Characteristics of those ATLL are typical. But prognosis is still unsatisfactory.

Fabrication of Laser-reduced Graphene Oxide in Liquid Nitrogen Environment

Porous structure of reduced graphene oxide (rGO) plays an important role in developing flexible graphene-based devices. In this work, we report a novel methodology for reduction of freestanding graphite oxide (GO) sheet by picosecond pulse laser direct writing in liquid nitrogen. Non-agglomerate and porous structure of rGO is fabricated successfully due to frozen effect during laser processing. Compared with laser-irradiated rGO developed in N₂ gas at ambient environment, the frozen rGO developed in liquid N₂ shows better ordered structure with less defects, crack-free morphology as well as better electron supercapacitor performance including 50–60 Ω/sq in sheet electrical resistance. Mechanism of cryotemperature photoreduction GO is also discussed.

Correlation between serum IL-16 and atopic dermatitis

This study aims to investigate the correlation between allergic sensitization of atopic dermatitis (AD) patients and their serum interleukin (IL)-16 levels. AD patients, healthy volunteers, and patients with psoriasis (N = 80, 35, 20, respectively) were tested for serum IL-16 and total and specific IgE levels by enzyme-linked immunosorbent assay, along with eosinophil counts. Serum allergen-specific IgE levels were determined, and skin-prick testing conducted in a subgroup of 45 AD patients. Based on specific IgE levels, AD patients were categorized into non-sensitized group 1 and sensitized group 2. Furthermore, they were sorted as non-sensitized group A and sensitized group B based on skin-prick results. Next, the serum IL-16 and total IgE levels in these subgroups were determined. Compared to levels in healthy volunteers and psoriasis patients, the serum IL-16 levels in AD patients were significantly higher (P < 0.001). Additionally, total serum IgE levels were significantly correlated with serum IL-16 levels and eosinophil counts. However, no correlation was observed between serum IL-16 levels and eosinophil counts. The serum IL-16 and total IgE levels in group 2 were also significantly elevated (P < 0.001) in contrast to those in group 1. Although we did not observe any significant difference between serum IL-16 levels in groups A and B, the total serum IgE level in group B was significantly higher than that in group A (P < 0.001). Thus, allergic sensitivity in AD patients correlates with total serum IgE as well as serum IL-16; the correlation with IL-6 is weaker.

Theoretical study of pre-formed hole geometries on femtosecond pulse energy distribution in laser drilling

Maxwell's wave equation was solved for fs laser drilling of silicon. The pre-formed hole wall's influence on the propagation behavior of subsequent laser pulses was investigated. The laser intensity at hole bottom shows distinct profile as compared with that at hole entrance. The multi-peaks and ring structure of the laser intensity were found at hole bottom. The position of maximum laser intensity (MLI) in relation to the wall taper angle was studied. It was found that the position of the MLI point would be closer to the hole entrance with increasing taper angle. This observation provides valuable information in predicting the position of plasma plume which is a key factor influencing laser drilling process. The elliptical entrance hole shape and zonal structure at the hole bottom reported in the literatures have been reasonably explained using the laser intensity distribution obtained in the present model.

Tunable dual-band perfect absorbers based on extraordinary optical transmission and Fabry-Perot cavity resonance

Magnetic resonance is considered to be a necessary condition for metamaterial perfect absorbers, and dual-band absorbers can be composed of a pair of metallic layers with anti-parallel surface currents. We designed and fabricated a tunable dual-band perfect absorber based on extraordinary-optical-transmission (EOT) effect and Fabry-Perot cavity resonance. The idea and the mechanism are completely different from the absorber based on the near-field interaction. The important advantage of our structure is that we can switch a single-band absorber to a dual-band absorber by changing the distance between two metallic layers and/or incident angle. The peak originating from the EOT effect becomes significantly narrower, resulting in an increase of the Q-factor from 16.88 to 49. The dual-band absorber can be optimized to be insensitive to the polarization of the incident electromagnetic wave by slightly modifying the absorber structure.

Influence of the material removal mechanisms on hole integrity in ultrasonic machining of structural ceramics

Micro-chipping via micro-cracks, due to rapid mechanical indentations by abrasive grits, is the fundamental mechanism of material removal during ultrasonic machining (USM) of hard-brittle materials like ceramics and glass. This study aims mainly to investigate the adverse effects of this inherent removal phenomena on the hole integrity such as entrance chipping, wall roughness and subsurface damage. It also presents the material removal mechanism happens in the gap between the tool periphery and the hole wall (called 'lateral gap'). To do so, experiments were conducted for drilling holes on three advanced structural ceramics, namely, silicon carbide, zirconia, and alumina. Earlier published basic studies on the initiation of different crack modes and their growth characteristics are employed to explain the experimental findings in this USM study. It is realized that the radial and the lateral cracks formed due to adjacent abrasives, which are under the tool face, extends towards radial direction of the hole resulting in entrance chipping. Additionally, the angle penetration and the rolling actions of the abrasives, which are at the periphery of the tool, contribute to the entrance chipping. Later on, in the 'lateral gap', the sliding (or abrasion) and the rolling mechanisms by the larger abrasives take part to material removal. However, they unfavorably produce micro-cracks in the radial direction resulting in surface and subsurface damages, which are ultimately responsible for higher wall-surface roughness. Since the size of micro-cracks in brittle materials is grit size dependent according to the earlier studied physics, it is realized that such nature of the hole integrity during USM can only be minimized by employing smaller grit size, but cannot fully be eliminated.

Investigation on CO(2) laser irradiation inducing glass strip peeling for microchannel formation

The study investigates the use of CO(2) laser to induce glass strip peeling off to form microchannels on soda lime gass substrate. The strip peeling exhibits a strong dependence on the energy deposition rate on the glass surface. In spite of the vast difference in the combination of laser power and scanning speed, when the ratio of the two makes the energy deposition rate in the range 3.0-6.0 J/(cm(2) s), the temperature rising inside glass will be above the strain point and reach the softening region of the glass. As a result, glass strip peeling is able to occur and form microchannels with dimensions of 20-40 μm in depth and 200-280 μm in width on the glass surface. Beyond this range, higher energy depsotion rate would lead to surface melting associated with solidification cracks and lower energy deposition rate causes the generation of fragment cracks.

Detection of the Treponema pallidum gene and variation of treponemal DNA load before and after therapy

We explored a genetic detection method for Treponema pallidum (TP) in the peripheral blood of infected patients to compare the loads of treponemal DNA before and after therapy and to see if this new technique enabled assessment of therapeutic effect and detection of serum resistance. Polymerase chain reaction was used for a qualitative detection of TP DNA in peripheral blood and then a semiquantitative method was adopted to estimate the load of TP DNA in blood, both before and after treatment of syphilis. Among 30 untreated patients, three cases were TP DNA-positive. Among 42 treated patients with demonstrated serum resistance, three cases were TP DNA-positive. Five cases in which the rapid plasma reagin had become negative had no detectable TP DNA in their peripheral blood. The TP DNA load in blood after treatment was significantly lower than that before therapy. We conclude that the detection of TP DNA in peripheral blood of TP-infected patients is not yet sufficiently sensitive, but we observed that TP DNA load declines significantly after treatment.

An inter-subspecies cloned buffalo (Bubalus bubalis) obtained by transferring of cryopreserved embryos via somatic cell nuclear transfer

The aim of this study was to explore the feasibility of cryopreservation of inter-subspecies cloned embryos in buffalo. In our experiment, river buffalo ear fibroblast nucleus was fused into swamp buffalo oocyte cytoplasm. The blastocyst formation rate for nuclear transfer of freshly thawed cells was not different from those of growing cells, confluent or serum-starved cells. A total of 122 cloned blastocysts derived from cryopreserved fibroblasts were cryopreserved and thawed, 37 were survived, the cryosurvival rate was 30.3%. The survived blastocysts were transferred into 15 recipient buffalos. Five of the recipients established pregnancy, but four of them aborted on day 53, 59, 145 and 179 of gestation respectively. One cross-bred buffalo (Murrah × Swamp buffalo (2n = 49) received three embryos delivered a 40.5 kg female calf by natural delivery on day 320 of gestation. Up to now (13-month old), the cloned calf has been growing well with no abnormity observed. These results demonstrated that cryopreservation of inter-subspecies cloned embryos is feasible to produce buffalo offspring.

RAPD-based genetic diversities and correlation with morphological traits in Camellia (Theaceae) cultivars in China

Camellia is an economically important ornamental plant that has many uses, such as in beverages, foods and medicines. We examined 15 Camellia cultivars in Wenzhou, China, using RAPD markers and measurements of three traits (petal color, flower diameter, blooming period). PCR amplification with 15 random primers produced 1935 bands, observed at 88 amplification loci; 77% of the amplified loci were polymorphic, with a mean of 4.5 polymorphic loci per primer. The similarity coefficient ranged from 0.5419 to 0.7933 among the 15 samples; the lowest value was between Manao (C. reticulata) and Feibai FR (C. japonica), and the largest value was between Chidan (C. japonica) and Yuanyang FG (C. japonica). Cluster analysis divided the 15 cultivars into two groups at the similarity coefficient of 0.65. A correlation was found between RAPD markers and petal color in the first group. No correlation was found between RAPD markers and the other traits (flower diameter, blooming period). This study provides information useful for the identification, classification, phylogenesis, and breeding of Camellia cultivars.

Femtosecond laser induced surface nanostructuring and simultaneous crystallization of amorphous thin silicon film

Ultrafast pulsed laser irradiation is demonstrated to be able to produce surface nano-structuring and simultaneous crystallization of amorphous silicon thin film in one step laser processing. After fs laser irradiation on 80 nm-thick a-Si deposited on Corning 1737 glass substrate, the color change from light yellow to dark brown was observed on the sample surface. AFM images show that the surface nano-spike pattern was produced on amorphous-Si:H film by fs laser irradiation. Furthermore, micro-Raman results indicate that the a-Si has been crystallized into nanocrystalline Si. Also, the absorptance of the fs laser treated Si thin film was found to increase in the spectrum range of below bandgap compared to original untreated a-Si. The developed process has a potential application in fabrication of high efficiency Si thin film solar cells.

Direct patterning in sub-surface of stainless steel using laser pulses

This paper reports for the first time on the direct creating microcavities in sub-surface of stainless steel using a single Nd:YAG laser pulse. The low peak power density is used in the process, which is in the order of 1 MW/cm(2). The formation of the microcavities in the sub-surface of stainless steel is an evidence of volume expulsion during laser-metal interaction. Direct patterning in the sub-surface of stainless steel is demonstrated by realizing a series of microcavities to form a pre-designed pattern. Potential applications of sub-surface patterning in metal, such as security marking, micro-heater, micro-insulator and micro-sensor, are discussed.

Study on the inter-subspecies nuclear transfer of river buffalo somatic cell nuclei into swamp buffalo oocyte cytoplasm

The objective of this study was to explore the feasibility of inter-subspecies somatic cell nuclear transfer (SCNT) of river buffalo (50 chromosomes) somatic cell nuclei into swamp buffalo (48 chromosomes) oocyte cytoplasm. The enucleated swamp buffalo oocytes were fused with four different types of river buffalo cells: freshly thawed ear fibroblasts, serum-starved ear fibroblasts, cumulus cells and ear fibroblasts from a cloned buffalo calf. As a result, the developmental competence of embryos reconstructed with freshly thawed ear fibroblasts was the poorest (P<0.01), while those of the other three types were not different from each other. Furthermore, the efficiency of swamp-swamp buffalo, swamp-river buffalo and bovine-buffalo SCNT were also compared. The results showed that the blastocyst rate of swamp-river reconstructed embryos was not different from swamp-swamp embryos, while significantly higher than that of bovine-buffalo embryos (P<0.01). A total of thirty cloned blastocysts derived from freshly thawed ear fibroblasts were transferred into thirteen recipient buffaloes, four recipients established pregnancy, while three of them aborted on Days 65, 75 and 90 of gestation, respectively. One cross-bred buffalo (Murrah x swamp, 49 chromosomes) receiving three embryos delivered a 39 kg female calf on Day 335 of gestation. These results indicate that the inter-subspecies SCNT is feasible to produce swamp-river buffalo embryos, and these can develop to full term and result in live buffalo calves.

Cloning the swamp buffalo SRY gene for embryo sexing with multiplex-nested PCR

The polymerase chain reaction (PCR) is an efficient method for sexing embryos. The objective of this study was to develop an accurate and reliable method for sexing swamp buffalo (Bubalus bubalis) embryos. The SRY gene from swamp buffalo genomic DNA was amplified by PCR, using primers based on the sequence of the Holstein SRY gene. This fragment was sequenced based on a BLAST search; the SRY gene was highly conserved. Using a Southern blot, there was a strong signal in genomic DNA only from male swamp buffalo. Two pairs of nested primers, targeted to amplify the swamp buffalo SRY conserved region, were designed for sex identification. Simultaneously, the G3PDH gene was co-amplified to serve as an internal control. A multiplex-nested PCR system was optimized by varying the following individually: concentrations of Mg(2+) and dNTPs, ratio of concentrations of primers and numbers of cycles. Biopsies of 27 IVF-derived embryos and 24 embryos fertilized with Y-chromosome-bearing sperm were examined. Using optimized procedures, clear signals following PCR amplification were obtained from all embryo samples; PCR amplification accuracy was further verified by comparing PCR and dot blots. We concluded that this PCR technique was highly reliable for sexing swamp buffalo embryos.

An Asian origin for subtype IV BK virus based on phylogenetic analysis

Similarly to other members of the Polyomaviridae family, BK virus (BKV) is thought to have co-evolved with its human host. BKV has four subtypes that are distinguishable by immunological reactivity, with two (subtypes I and IV) being most prevalent in human populations. Subtype I is the major subtype worldwide, whereas subtype IV is prevalent in East Asia and Europe but rare in Africa. The geographic distribution pattern of subtype IV BKV is in apparent disagreement with the hypothesis that BKV co-evolved with humans, since subtype IV rarely occurs in Africa. To elucidate the origin of subtype IV, 53 complete subtype IV sequences derived from East Asians and Europeans were subjected to a detailed phylogenetic analysis using the maximum-likelihood and neighbor-joining methods. We identified six subgroups (a1, a2, b1, b2, c1, and c2) that formed a tree represented by the formula: "(a1, a2), ((b1, b2), (c1, c2))." Interestingly, we found a close correlation between subtype IV subgroups and population geography; thus, all subgroups except c2 were prevalent in particular East Asian populations, with c2 occurring in both Europe and Northeast Asia. From these findings, we conclude that subtype IV of BKV now prevalent in modern humans is derived from a virus that infected ancestral Asians. We introduce two hypotheses to explain how ancestral Asians became infected with subtype IV BKV.

Relationships between BK virus lineages and human populations

BK polyomavirus (BKV) is ubiquitous in human populations, infecting children asymptomatically and then persisting in the kidney, in which it can cause nephropathy in renal transplant patients. BKV isolates are classified into four subtypes (I-IV) using serological or genotyping methods, and subtype I is further divided into four subgroups, Ia, Ib-1, Ib-2, and Ic, based on DNA sequence variations. To clarify whether there is an association between BK virus lineages and human populations, we examined BKV-positive urine samples collected from immunocompetent individuals at various locations in Europe, Africa, and Asia. Partial BKV DNA sequences (n=299) in these samples were determined and subjected to phylogenetic and single nucleotide polymorphism analysis to classify BKV isolates around the world. The validity of the classification was confirmed by analyses based on complete BKV DNA sequences. Subtype I was the major subtype throughout the studied regions, and subtype IV was prevalent only in Asia and Europe. Subtype-I subgroups showed close relationships to major geographical areas. It has recently been shown that JC virus (a human polyomavirus closely related to BKV) co-evolved with human populations, and the present study thus suggests that host-linked evolution is the general mode of polyomavirus evolution. Additionally, our results indicate certain unique aspects of the relationship between BKV and humans.

[Genetic changes in JC virus possibly associated with progressive multifocal leukoencephalopathy]

Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.

[Genetic changes possibly associated with progressive multifocal leukoencephalopathy]

Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.

[Detection of novel rearrangement of the JC virus gene in a case of progressive multifocal leukoencephalopathy with adult T-cell leukemia]

A 53-year-old man with adult T-cell leukemia (ATL) developed progressive left hemiparesis and left homonymous hemianopsia. Magnetic resonance imaging (MRI) one month later showed multiple high-intensity lesions in the white matter of both occipital lobes, with predominance in the right side. Detection of JCV genome with polymerase chain reaction in his cerebrospinal fluid subsequently confirmed the diagnosis of progressive multifocal leukoencephalopathy (PML). He was admitted to our hospital. The serum level of soluble interleukin-2 receptor in the patient increased, and both edema and new Gd-enhanced lesions were observed in the cortex of the occipital lobe. He was treated with systemic administrations of Pirarubicin. Cyclophosphamide, and Prednisolone. as well as intrathecal injection of Methotrexate and Cytarabine. Although these treatments temporarily alleviated the symptoms of PML. the ATL spread to the liver and kidney. He died of multiple organ failure. Analysis of his JCV genes revealed that there were three types of rearrangements in the regulatory domains of the JCV genes. All three types lacked the domain B. and two had duplicate domain A. This is the first report of the simultaneous detection of three different types of rearrangements in JCV genes in a single patient. It has been reported that white-matter lesions caused by typical PML are not enhanced in Gd-MRI. However. the lesions seen in this patient were enhanced in Gd-MRI. Such enhancement might be attributable to the modification of the lesions through the direct invasion of ATL cells to the central nervous system.

Identification of a genomic subgroup of BK polyomavirus spread in European populations

BK polyomavirus (BKV) is highly prevalent in the human population, infecting children without obvious symptoms and persisting in the kidney in a latent state. In immunosuppressed patients, BKV is reactivated and excreted in urine. BKV isolates worldwide are classified into four serologically distinct subtypes, I-IV, with subtype I being the most frequently detected. Furthermore, subtype I is subdivided into subgroups based on genomic variations. In this study, the distribution patterns of the subtypes and subgroups of BKV were compared among four patient populations with various immunosuppressive states and of various ethnic backgrounds: (A) Finnish renal-transplant recipients; (B) Irish/English haematopoietic stem-cell transplant recipients with and without haemorrhagic cystitis; (C) Japanese renal-transplant recipients; and (D) Japanese bone-marrow transplant recipients. The typing sequences (287 bp) of BKV in population A were determined in this study; those in populations B-D have been reported previously. These sequences were subjected to phylogenetic and single nucleotide polymorphism analyses. Based on the results of these analyses, the BKV isolates in the four patient populations were classified into subtypes and subgroups. The incidence of subtype IV varied significantly among patient populations. Furthermore, the incidence of subgroup Ib-2 within subtype I was high in populations A and B, whereas that of Ic was high in populations C and D (P<0.01). These results suggest that subgroup Ib-2 is widespread among Europeans, whereas Ic is unique to north-east Asians. Furthermore, a phylogenetic analysis based on complete BKV DNA sequences supported the hypothesis that there is geographical separation of European and Asian BKV strains.

Age-related urinary excretion of BK polyomavirus by nonimmunocompromised individuals

Two polyomaviruses, BK virus (BKV) and JC virus (JCV), are ubiquitous in the human population, generally infecting children asymptomatically and then persisting in renal tissue. It is generally thought that reactivation leads to productive infection for both viruses, with progeny shed in the urine. Several studies have shown that the rate of JC viruria increases with the age of the host, but a systematic approach to examine the shedding of BKV has not been developed. To elucidate the relationship between BK viruria and host age, we obtained urine from donors (healthy volunteers or nonimmunocompromised patients) who were divided into nine age groups, each containing 50 members. A high-sensitivity PCR was used to detect BKV and JCV DNA from urinary samples, and the specificity of amplification was confirmed by sequencing or restriction analysis of the amplified fragments. The rate of BK viruria was relatively low in subjects aged <30 years but gradually increased with age in subjects aged > or =30 years. However, BK viruria was less frequent than JC viruria in adults. The detected BKV isolates were classified into subtypes, and detection rates for individual subtypes were compared among age groups; this analysis showed that viruria of subtypes I (the most prevalent subtype) and IV (the second most prevalent subtype) occurred more frequently in older subjects. Therefore, our results reveal new aspects of BK viruria in nonimmunocompromised individuals.

Effect of femtosecond laser irradiation on structure of UV grade fused silica

A p-polarized femtosecond laser beam was used to irradiate a UV grade fused silica to create microchannels, which are useful for producing optical gratings or micro fluidics devices. The laser irradiated surface was characterized using optical microscope, stylus profiler, SEM, XRD and TEM. A special technique was used to protect the laser irradiated surfaces in preparing cross-sectional TEM samples. The XRD spectra and TEM observation reveal that structure of the fused silica remain amorphous after the femtosecond laser irradiation.

Quantification of thermal energy deposited in silicon by multiple femtosecond laser pulses

We report our study of deposited thermal energy in silicon induced by multiple-pulse femtosecond laser irradiation. Using infrared thermography, we quantified through in situ direct measurement of temperature fields that a significant portion of laser power (two-thirds or more) was deposited into the silicon substrate instead of being reflected or carried away with the ablated material. This is believed to be the first reported study of direct in situ measurement of temperature fields as the result of deposited thermal energy from multiple femtosecond laser pulses. Our simulation results support the measured data.

Phylogenetic analysis of major African genotype (Af2) of JC virus: Implications for origin and dispersals of modern Africans

Both mtDNA and the Y chromosome have been used to investigate how modern humans dispersed within and out of Africa. This issue can also be studied using the JC virus (JCV) genotype, a novel marker with which to trace human migrations. Africa is mainly occupied by two genotypes of JCV, designated Af1 and Af2. Af1 is localized to central/western Africa, while Af2 is spread throughout Africa and in neighboring areas of Asia and Europe. It was recently suggested that Af1 represents the ancestral type of JCV, which agrees with the African origin of modern humans. To better understand the origin of modern Africans, we examined the phylogenetic relationships among Af2 isolates worldwide. A neighbor-joining phylogenetic tree was constructed based on the complete JCV DNA sequences of 51 Af2 isolates from Africa and neighboring areas. According to the resultant tree, Af2 isolates diverged into two major clusters, designated Af2-a and -b, with high bootstrap probabilities. Af2-a contained isolates mainly from South Africa, while Af2-b contained those from the other parts of Africa and neighboring regions of Asia and Europe. These findings suggest that Af2-carrying Africans diverged into two groups, one carrying Af2-a and the other carrying Af2-b; and that the former moved to southern Africa, while the latter dispersed throughout Africa and to neighboring regions of Asia and Europe. The present findings are discussed with reference to relevant findings in genetic and linguistic studies.

Subtype I BK polyomavirus strains grow more efficiently in human renal epithelial cells than subtype IV strains

BK polyomavirus (BKPyV) is ubiquitous in human populations, infecting children without obvious symptoms and persisting in the kidney. BKPyV isolates have been classified into four subtypes (I-IV) using either serological or genotyping methods. In general, subtype I occurs most frequently, followed by subtype IV, with subtypes II and III rarely detected. As differences in growth capacity in human cells possibly determine the proportion of the four subtypes of BKPyV in human populations, here the growth properties of representative BKPyV strains classified as subtype I or IV in renal proximal tubule epithelial cells (HPTE cells) of human origin were analysed. HPTE cells were transfected with four and three full-length BKPyV DNAs belonging to subtypes I and IV, respectively, and cultivated in growth medium. Virus replication, detected using the haemagglutination assay, was observed in all HPTE cells transfected with subtype I BKPyV DNAs, whereas it was markedly delayed or not detected in those transfected with subtype IV BKPyV DNAs. It was confirmed that the transfected viral DNAs induced virus replication in HPTE cells. Furthermore, it was found that BKPyVs with archetypal transcriptional control regions replicated in HPTE cells, with only the occasional emergence of variants carrying rearranged transcriptional control regions. Essentially the same results as described above were obtained with renal epithelial cells derived from whole kidney. Thus, it was concluded that subtype I BKPyV replicates more efficiently than subtype IV BKPyV in human renal epithelial cells, supporting the hypothesis that growth capacity in human cells is related to the proportion of BKPyV subtypes in human populations.

Evolution of BK virus based on complete genome data

The human polyomavirus BK virus (BKV) is ubiquitous in humans, infecting children asymptomatically. BKV is the only primate polyomavirus that has subtypes (I-IV) distinguishable by immunological reactivity. Nucleotide (nt) variations in a major capsid protein (VP1) gene region (designated the epitope region), probably responsible for antigenic diversity, have been used to classify BKV isolates into subtypes. Here, with all the protein-encoding gene sequences, we attempted to elucidate the evolutionary relationships among 28 BKV isolates belonging to subtypes I, III, and IV (no isolate belonging to subtype II, a minor one, was included). First, using the GTR + Gamma + I model, maximum likelihood trees were reconstructed for individual viral genes as well as for concatenated viral genes. On the resultant trees, the 28 BKV isolates were consistently divided into three clades corresponding to subtypes I, III, and IV, although bootstrap probabilities are not always high. Then we used more sophisticated likelihood models, one of which takes account of codon structure, to elucidate the phylogenetic relationships among BKV subtypes, but the phylogeny of the deep branchings remained ambiguous. Furthermore, the possibility of positive selection in the evolution of BKV was examined using the nonsynonymous/synonymous rate ratio as a measure of selection. An analysis based on entire genes could not detect any strong evidence for positive selection, but that based on the epitope region identified a few sites potentially under positive selection (these sites were among those showing subtype linked polymorphisms).

Stability of the BK polyomavirus genome in renal-transplant patients without nephropathy

To clarify the stability of the BK polyomavirus (BKPyV) genome in renal transplant (RT) recipients, three to five complete BKPyV genomes from each of six RT recipients with surviving renal allografts were molecularly cloned. The complete sequences of these clones were determined and compared in each patient. No nucleotide difference was detected among clones in two patients, and a few nucleotide variations were found among those in four patients. In each of these patients a parental sequence (usually the major sequence), from which variant sequences (usually minor sequences) with nucleotide substitutions would have been generated, were identified. A comparison between the parental and variant sequences in each patient identified a single nucleotide substitution in each variant sequence. From these findings, it was concluded that the genome of BKPyV is stable in RT recipients without nephropathy, with only minor nucleotide substitutions in the coding region.

Characterization of the VP1 loop mutations widespread among JC polyomavirus isolates associated with progressive multifocal leukoencephalopathy

Recently, we found that JC polyomavirus (JCPyV) associated with progressive multifocal leukoencephalopathy (PML) frequently undergoes amino acid substitutions (designated VP1 loop mutations) in the outer loops of the major capsid protein, VP1. To further characterize the mutations, we analyzed the VP1 region of the JCPyV genome in brain-tissue or cerebrospinal fluid samples from 20 PML patients. VP1 loop mutations occurred far more frequently than silent mutations. Polymorphic residues were essentially restricted to three positions (55, 60, and 66) within the BC loop, one (123) within the DE loop, and three (265, 267, and 269) within the HI loop. The mutations at most polymorphic residues showed a trend toward a change to specific amino acids. Finally, we presented evidence that the VP1 loop mutations were associated with the progression of PML. These findings should form the basis for elucidating the biological significance of the VP1 loop mutations.

Genetic diversity of JC virus in the Saami and the Finns: implications for their population history

The JC virus (JCV) genotyping method was used to gain insights into the population history of the Saami and the Finns, both speaking Finno-Ugric languages and living in close geographic proximity. Urine samples from Saami and Finns, collected in northern and southern Finland, respectively, were used to amplify a 610-bp JCV-DNA region containing abundant type-specific mutations. Based on restriction site polymorphisms in the amplified fragments, we classified JCV isolates into one of the three superclusters of JCV, type A, B, or C. All 15 Saami isolates analyzed and 41 of 43 Finnish isolates analyzed were classified as type A, the European type, and two samples from Finns were classified as type B, the African/Asian type. We then amplified and sequenced a 583-bp JCV-DNA region from the type A isolates of Saami and Finns. According to type-determining nucleotides within the region, we classified type A isolates into EU-a1, -a2, or -b. Most type A isolates from Saami were classified as EU-a1, while type A isolates from Finns were distributed among EU-a1, EU-a2, and EU-b. This trend in the JCV-genotype distribution was statistically significant. On a phylogenetic tree based on complete sequences, most of the type A isolates from Saami were clustered in a single clade within EU-a1, while those from Finns were distributed throughout EU-a1, EU-a2, and EU-b. These findings are discussed in the context of the population history of the Saami and the Finns. This study provides new complete JCV DNA sequences derived from populations of anthropological interest.

New sequence polymorphisms in the outer loops of the JC polyomavirus major capsid protein (VP1) possibly associated with progressive multifocal leukoencephalopathy

JC polyomavirus(JCPyV) causes progressive multifocal leukoencephalopathy (PML) in patients with decreased immune competence. To elucidate genetic changes in JCPyV associated with the pathogenesis of PML, multiple complete JCPyV DNA clones originating from the brains of three PML cases were established and sequenced. Although unique rearranged control regions occurred in all clones, a low level of nucleotide variation was also found in the coding region. In each case, a parental coding sequence was identified, from which variant coding sequences with nucleotide substitutions would have been generated. A comparison between the parental and variant coding sequences demonstrated that all 12 detected nucleotide substitutions gave rise to amino acid changes. Interestingly, seven of these changes were located in the surface loops of the major capsid protein (VP1). Finally, 16 reported VP1 sequences of PML-type JCPyV (i.e. derived from the brain or cerebrospinal fluid of PML patients) were compared with their genotypic prototypes, generated as consensus sequences of representative archetypal isolates belonging to the same genotypes; 13 VP1 proteins had amino acid changes in the surface loops. In contrast, VP1 proteins from isolates from the urine of immunocompetent and immunosuppressed patients rarely underwent mutations in the VP1 loops. The present findings suggest that PML-type JCPyV frequently undergoes amino acid substitutions in the VP1 loops. These polymorphisms should serve as a new marker for the identification of JCPyV isolates associated with PML. The biological significance of these mutations, however, remains unclear.

FUNCTION OF THE LOWER URINARY TRACT IN MICE LACKING α1d-ADRENOCEPTOR

PURPOSE

alpha1-Adrenoceptor (AR) blockers are known to relieve not only voiding symptoms, but also storage symptoms in elderly men. We investigated lower urinary tract function in mice lacking alpha1d-AR using frequency/volume analysis and filling cystometry.

MATERIALS AND METHODS

A total of 10, 12-week-old female alpha1d-knockout (KO) mice and 10 age matched female wild-type (WT) mice were studied. Each mouse was placed in a metabolic cage connected to a digital scale and personal computer. Under a 12/12-hour dark/light photocycle voiding frequency and volume were recorded for 48 hours. After frequency/volume analysis filling cystometry was performed with the mice awake and without restraint. The expression of alpha1-AR subtype mRNA in the bladder of mice in each group was quantified using real-time polymerase chain reaction.

RESULTS

Mean daily voiding frequency +/- SD in alpha1d-KO mice was 9.0 +/- 2.1, significantly lower than 15.9 +/- 5.2 in WT mice (p = 0.0048). Mean volume per void in alpha1d-KO mice was significantly larger than in WT mice (0.24 +/- 0.02 vs 0.16 +/- 0.03 ml, p = 0.0096). Similarly cystometric analysis demonstrated larger bladder capacity (140%, p = 0.0008) and voided volume (146%, p = 0.0048) in alpha1d-KO mice compared with those in WT mice. No significant difference in maximum pressure at void was observed between the 2 groups. In WT mice the amount of alpha1a, alpha1b and alpha1d-AR subtype mRNA in the bladder was 5.2 +/- 0.7, 1.0 +/- 0.1 and 6.3 +/- 0.7 gene copies per ng total RNA, respectively. In contrast, alpha1d-AR transcript was not detectable in alpha1d-KO mice but alpha1a and alpha1b-AR expression was similar to that in WT mice.

CONCLUSIONS

The results demonstrate that the alpha1d-AR subtype has an important role in regulating bladder function. They theoretically support a clinical finding that alpha1-blockers with significant affinity for alpha1d-AR are effective for treating storage symptoms associated with benign prostatic obstruction.

JC virus genotyping using formalin-fixed, paraffin-embedded renal tissues

Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time.

Enhanced human osteoblast cell adhesion and proliferation on 316 LS stainless steel by means of CO2 laser surface treatment

An effective and novel technique for improving the biocompatibility of a biograde 316 LS stainless steel through the application of CO(2) laser treatment to modify the surface properties of the material is described herein. Different surface properties, such as surface roughness, surface oxygen content, and surface energy for CO(2) laser-treated 316 LS stainless steel, untreated, and mechanically roughened samples were analyzed, and their effects on the wettability characteristics of the material were studied. It was found that modification of the wettability characteristics of the 316 LS stainless steel following CO(2) laser treatment was achieved. This improvement was identified as being mainly due to the change in the polar component of the surface energy. One-day cell adhesion tests showed that cells not only adhered and spread better, but also grew faster on the CO(2) laser-treated sample than on either the untreated or mechanically roughened sample. Further, compared with the untreated sample, MTT cell proliferation analysis revealed that the mechanically roughed surface resulted in a slight enhancement, and CO(2) laser treatment brought about a significant increase in cell proliferation. An increase in the wettability of the 316 LS stainless steel was observed to positively correlate with the cell proliferation.

Subtypes of BK virus prevalent in Japan and variation in their transcriptional control region

BK polyomavirus (BKV) is ubiquitous in the human population, infecting children without obvious symptoms, and persisting in the kidney in a latent state. In immunosuppressed patients, BKV is reactivated and excreted in urine. BKV isolates have been classified into four subtypes (I-IV) using either serological or genotyping methods. To elucidate the subtypes of BKV prevalent in Japan, the 287 bp typing region in the viral genome was PCR-amplified from urine samples of 45 renal transplant (RT) and 31 bone-marrow transplant (BMT) recipients. The amplified fragments were subjected to a phylogenetic or RFLP analysis to determine the subtypes of BKV isolates in urine samples. Subtypes I, II, III and IV were detected, respectively, in 70-80, 0, 2-3 and 10-20 % of the BKV-positive patients in both patient groups. This pattern of distribution was virtually identical to patterns previously demonstrated in England, Tanzania and the United States, suggesting that BKV subtypes are distributed similarly in various human populations. Furthermore, transcriptional control regions (TCRs) were PCR-amplified from the urine samples of 25 RT and 20 BMT recipients, and their nucleotide sequences were determined. The basic TCR structure (the so-called archetype configuration) was observed in most isolates belonging to subtypes I, III and IV (subtype II isolates were not available), albeit with several nucleotide substitutions and a few single-nucleotide deletions (or insertions). Only three TCRs carried extensive sequence rearrangements. Thus, it was concluded that the archetypal configuration of the BKV TCR has been conserved during the evolution of BKV.