[Exosomes derived from miR-133a-3p engineered mesenchymal stem cells promote myocardial repair in rats after acute myocardial infarction]

Objective: To investigate the effects of exosome derived from miR-133a-3p engineered human umbilical cord blood mesenchymal stem cells (ucMSC) on myocardial repair after acute myocardial infarction (AMI) in rats. Methods: UcMSC was amplified and cultured in vitro. Lentiviral carrying miR-133a-3p and negative control vectors were transfected into ucMSC. Exosomes secreted by the transfected ucMSC were named miR-133a-3p-Exo and miR-NC-Exo, respectively. The AMI model of rats was established by ligation of the left anterior descending coronary artery. MiR-133a-3p-Exo or miR-NC-Exo were then injected into the border zone of the infarct area. Cardiac function was assessed by echocardiography after twenty-eight days of intervention, and Masson staining was used to evaluate the area of myocardial fibrosis post-AMI. The myocardial apoptosis after infarction was evaluated by TUNEL staining and the angiogenesis after infarction was evaluated by immunofluorescence staining in the current study. Results: Compared with the miR-NC-Exo group, the left ventricular ejection fraction in the miR-133a-3p-Exo group was significantly increased ((47.4%±9.8%) vs. (64.2%±8.9%), P<0.05). While the myocardial fibrosis area ((31.2%±7.3%) vs. (18.0%±1.5%), P<0.01) and the percentage of apoptotic cardiomyocytes ((25.6%±3.6%) vs. (15.1%±4.4%), P<0.05) was significantly reduced in the miR-133a-Exo group. Besides, the expression of CD31 and α-smooth muscle actin (α-SMA) were also increased significantly in the miR-133a-3p-Exo group compared to the miR-NC-Exo group (CD31: (2.9±0.9) vs. (13.9±2.0), P<0.000 1, α-SMA: (3.5±0.9) vs. (11.0±1.6), P<0.000 1). Conclusion: Exosome derived from miR-133a-3p engineered ucMSC effectively inhibited myocardial apoptosis and promoted angiogenesis, thus improving the cardiac function after myocardial infarction in rats.

[Characteristics of daytime napping and its correlation with chronic diseases in Chinese adults]

Objective: To describe the prevalence of daytime nap habit in participants of the China Kadoorie Biobank (CKB) study, across 10 study regions and explore its correlation with prevalence of major chronic diseases. Methods: Participants with a self-reported pre-diagnosis of any cancer at baseline survey were excluded. Logistic regression models were used to analyze the differences in study regions and age distribution of the prevalence daytime nap habit, and its correlation with the prevalence of diabetes, hypertension, coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), and chronic liver diseases. Results: Among 510 145 participants, 39.9% had daytime nap habit in summer and 20.8% had daytime nap habit all the year round. Urban-rural differences were observed in the prevalence of summer nap habit and perennial nap habit. Daytime nap in summer was common in rural areas and Suzhou, with prevalence ranged from 32.9% to 73.3%. Haikou and Liuzhou had higher prevalence of perennial nap (60.4% and 63.3%). The proportion of people with daytime nap habit all the year round increased with age (P for trend <0.001), the proportion was highest in those aged 70- years (31.9%). Daytime nap habit in summer was positively correlated with the prevalence of diabetes, hypertension, CHD and chronic liver disease with OR of 1.10 (95%CI: 1.07-1.14), 1.03 (95%CI:1.02-1.05), 1.07 (95%CI: 1.02-1.12) and 1.07 (95%CI:1.00-1.14), respectively. Daytime nap habit all the year round was positively correlated with the prevalence of diabetes, hypertension, CHD, stroke, COPD and chronic liver disease with OR of 1.33 (95%CI: 1.29-1.37), 1.11 (95%CI: 1.09-1.13), 1.39 (95%CI: 1.33-1.45), 1.33 (95%CI: 1.26-1.41), 1.12 (95%CI: 1.08-1.16) and 1.27 (95%CI:1.18-1.37) respectively. Conclusion: There were regional and age differences in prevalence of daytime nap habit among CKB participants. Daytime nap habit, especially daytime nap habit all the year round, was positively correlated with the prevalence of major chronic diseases.

[Correlation between sleep status and frailty in adults aged 30-79 years in China]

Objective: To explore the correlation between sleep status and frailty in adults aged 30-79 years in China, and explore the potential effect modification of general and central obesity. Methods: Based on the baseline data of the China Kadoorie Biobank, we used multinomial logistic regression to analyze the correlation between long and short sleep duration, insomnia disorder, snoring, and unhealthy sleep score with risks of pre-frailty and frailty. Both overall and obesity-stratified analyses were performed. Result: Among the 512 724 participants, 2.3% had frailty and 40.1% had pre-frailty. There was a U-shaped relationship between sleep duration and frailty score. Short (OR=1.21, 95%CI: 1.19-1.23) or long sleep duration (OR=1.19, 95%CI: 1.17-1.21), insomnia disorder (OR=2.09, 95%CI: 2.02-2.17), and snoring (OR=1.61, 95%CI: 1.59-1.63) were all positively correlated with pre-frailty, and dose-response relationships were observed between unhealthy sleep score and pre-frailty (P for trend<0.001), with OR values of 1.46 (1.44-1.48), 1.97 (1.93-2.00) and 3.43 (3.21-3.67) respectively for those having unhealthy sleep score of 1 to 3. These sleep problems were also positively correlated with frailty. Compared with the overweight or obesity group, stronger relationships were observed between short sleep duration and frailty or pre-frailty and between insomnia disorder and pre-frailty, while the relationships between snoring and frailty and pre-frailty were weaker in the participants with normal weight (P for interaction <0.007 for all). We also observed similar effect modification by central obesity. Conclusion: Long or short sleep duration, insomnia disorder, snoring and higher unhealthy sleep scores were positively correlated with pre-frailty or frailty, general and central obesity status could modify the relationships.

[Application of internal carotid artery stent in skull base surgery]

Objective: To report the experience of the application of internal carotid artery stent in skull base surgery, and to clarify the important role of internal carotid artery stent in skull base surgery. Methods: A retrospective study of 22 cases with skull base neoplasms implanted with internal carotid artery stents in the Department of ENT Head and Neck Surgery at the Sixth People's Hospital affiliated with Shanghai Jiao Tong University between July 2019 and January 2021 was conducted. Among them, 17 were male and 5 were female, aged between 33 and 75 years. There were 5 cases on the left, 16 cases on the right, and 1 case on both sides. Of these, there were 4 cases of jugular paraganglioma, 1 case of chondrosarcoma in the jugular foramen, 1 case of carotid body paraganglioma, and 16 cases of nasopharyngeal carcinoma after radiotherapy. Results: The degree of internal carotid artery erosion was assessed by computed tomography angiography (CTA), magnetic resonance imaging and digital subtraction angiography (DSA) images in 22 patients before surgery. It was found that the internal carotid artery was involved to varying degrees in all patients, so internal carotid artery stents were implanted before surgery. Tumor tissue was found to surround the internal carotid artery to varying degrees. Total or subtotal tumor resection was performed in all patients, and no intraoperative and postoperative complications occurred. The postoperative follow-up was 5 months to 2 years, and all patients had no complications such as spontaneous bleeding and pseudo aneurysm. There were no signs of stenosis or occlusion of the internal carotid artery stent segment in all cases. Conclusions: For patients with skull base tumors, preoperative imaging indicates the limited involvement of the internal carotid artery, and internal carotid artery stent implantation before surgery is a safe and effective treatment.

[Consensus of experts on the oral health management and medical risk prevention for the patients with chronic airway diseases (2022 edition)]

Today, there is greater awareness on the association between oral diseases and respiration diseases after the outbreak of COVID-19. However, confusion regarding the oral health management and medical risk prevention for patients with chronic airway diseases has been remained among dental clinicians. Therefore, the dental experts of the Fifth General Dentistry Special Committee, Chinese Stomatological Association, combined with the experts of respiratory and critical care medicine, undertook the formation of consensus on the oral health management of patients with chronic airway diseases in order to help dental clinicians to evaluate medical risks and make better treatment decision in clinical practice. In the present consensus report, the relationship of oral diseases and chronic airway diseases, the oral health management and the treatment recommendations of patients with chronic airway diseases are provided.

[Consensus of experts on the medical risk prevention for the patients with cardiovascular diseases during dental treatment (2022 edition)]

With the aging process of population in the society, the prevalence of cardiovascular diseases (CVD) in China is increasing continuously and the number of dental patients with CVD is increasing gradually too. Due to the lack of guidelines for dental patients with CVD in our country, how to implement standardized preoperative evaluation and perioperative risk prevention remains a problem to be solved for dentists at present. The present expert consensus was reached by combining the clinical experiences of the expert group of the Fifth General Dentistry Special Committee, Chinese Stomatological Association and respiratory and cardiology experts in diagnosis and treatment for CVD patients, and by systematically summarizing the relevant international guidelines and literature regarding the relationship between CVD and oral diseases and the diagnosis and treatment of dental patients with heart failure, hypertension and antithrombotic therapy. The consensus aims to provide, for the dental clinicians, the criteria on diagnosis and treatment of CVD in dental patients in China so as to reduce the risk and complications, and finally to improve the treatment levels of dental patients with CVD in China.

[Research progress in association of neurological disorders and periodontal diseases]

Periodontal diseases are inflammatory diseases caused by oral pathogens around the periodontal supporting tissues, leading to systemic and chronic inflammatory conditions. The continuous chronic systemic inflammation may be a trigger of neuroinflammation, which is the prominent feature of a variety of neurological disorders. It implies that there may be a causal link between periodontal diseases and neurological disorders. This article presents epidemiological and biological evidences that periodontal diseases can induce or exacerbate neurological disorders, including Alzheimer's disease, Parkinson's disease, multiple sclerosis and major depressive disorder, and analyzes the possible mechanisms. The importance of maintaining oral health as well as preventing and treating periodontal diseases are emphasized. At the same time, this may provide novel approaches to study the relationship between periodontal diseases and neurological disorders in the prevention and treatment strategies of neurological disorders.

[Molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus during 2017-2018 at a hospital in Shanghai]

Objective: To identify the epidemic clones of MRSA isolates at a hospital in shanghai. Methods: A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates. Results: A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%). Conclusion: ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

[A multicenter survey of the accessibility of essential medicines for children in China]

Objective: To investigate the availability, prices and affordability of essential medicines in pediatric population across China, in the hope of improving rational use of medicines. Methods: A multicenter cross-sectional survey of medicine prices, availability and affordability was conducted in 17 provinces, municipalities and autonomous region across east, south-central part, west and north of China. Data on 42 medicines used in pediatric population, both original and generic, were collected in 55 public hospitals from May 26 to June 2, 2017. Availability was expressed as the percentage of hospitals with stock of the target medicine on the day of data collection,and median price ratio (MPR) was the ratio of price upon investigation to international reference. Based on national minimum daily wage, affordability represents the number of working days needed to earn the expense which covers a standard course using the target medicine. Statistical software SPSS 13.0 was applied for descriptive analysis of availability, MPR and affordability. Results: Mean Availability of original and generic medicine was 33% and 32%, with median MPR being 5.43 and 1.55. Among the 19 medicines with price information for both original and generic product, the median MPR was 7.73 and 2.04 respectively. Regarding the five medicines used to treat four common pediatric diseases (pneumonia,peptic ulcer, congenital hypothyroidism, refractory nephrotic syndrome), the affordability was 0.63 (0.16-6.17) d for generic medicine, and 1.03 (0.16-11.53) d for its original counterpart. Conclusions: The availability to both original and generic products of the 42 medicines used in pediatric population was low in China. The prices of generic medicines seem to be lower and affordability higher than those of original medicines. There is an urgent need to improve the availability and affordability of pediatric medicines.

[Evaluation of neurovascular function in mouse cortex using multispectral optical imaging after ischemic stroke]

Objective: To acquire the signal of neuron excitability and blood oxygen in mouse cortex after ischemic stroke, and to clarify the relationship between the change of neurovascular function and the degree of cerebral infarction. Methods: The male C57BL/6 mouse(n=20) about 6-8 weeks and 20 g weight were produced the embolic stroke modal by photochemical injury. The mouse cortex was scanned by the multispectral optical imaging while using electric stimulation in 1, 3 and 7 d after operation. Then several data around the infarction were acquired including neuron excitability, the total hemoglobin concentration and deoxygenated hemoglobin concentration. The ischemic cerebral infarction size was analyzed by TTC staining. Plasma TNF-α concentration was measured by enzyme-linked immunosorbent assay(ELISA). And modified neurological severity score (mNSS) was recorded after ischemic stroke(n=30). Then correlativity analysis was used between the optical signals and three indicators of cerebral infarction degree. Results: The changes of neuron excitability signals were 1.15%±0.28%, 2.84%±1.06%, 2.21%±0.55%. The total hemoglobin concentration signals were 3.71%±2.76%,3.19%±2.70%,4.27%±3.05%. The deoxygenated hemoglobin concentration signals were 2.93%±2.33%, 3.60%±1.74%, 2.08%±1.28%. The neural signal was correlated to cerebral infarction size, plasma TNF-α concentration and mNSS(r=-0.441, -0.449,-0.404, all P<0.05), and mNSS had a great effect on neuron excitability(β=-0.169,P<0.05). Meanwhile, the total hemoglobin concentration was correlated to cerebral infarction size(r=0.440,P<0.05). Conclusion: The signal of neuron and blood oxygen is able to represent the change of neurovascular function and evaluate the progression of ischemic stroke.

[Correlation between serum interleukin-38 and acute exacerbation of chronic obstructive pulmonary disease with pulmonary embolism]

Objective: To investigate the correlation between serum interleukin-38 (IL-38) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with pulmonary embolism (PE). Methods: The 94 patients with AECOPD admitted to Tianjin Chest Hospital from August 2015 to April 2018 were suspected of PE. They were divided into two groups based on CT pulmonary angiography (CTPA) and color Doppler ultrasound of lower extremity veins: 39 cases in PE group and 55 cases in Non-PE group. The general data and laboratory examination results of these subjects were recorded. Serum IL-38 was measured by double antibody enzyme-linked immunosorbent assays (ELISA). The between-group differences of above parameters were analyzed. Pearson correlation or Spearman rank correlation was used to analyze the association of IL-38 with each variable in AECOPD patients. Binary Logistic regressions were conducted to determine the risk factors of AECOPD with PE. ROC curve was used to assess the value of serum IL-38 in predicting AECOPD with PE. Results: The serum level of IL-38 was lower in PE group than in Non-PE group [46.3 (33.1, 58.1) vs 61.5 (46.6, 72.5) ng/L, P<0.05]. Correlation analysis showed that serum IL-38 levels were negatively correlated with C reactive protein and fibrinogen in patients with AECOPD (r=-0.38,-0.29, all P<0.05). Binary Logistic regressions showed that lower serum IL-38 level was a risk factor of AECOPD with PE (OR=0.78, 95%CI: 0.61-0.94, P<0.05). The area under the ROC curve was 0.74 (95% CI: 0.63-0.84, P<0.05). When cutoff value of serum IL-38 was 52.1ng/L, the sensitivity was 70.9% and the specificity was 69.2% respectively. Conclusion: IL-38 could relieve the hypercoagulability by inhibiting inflammation in patients with AECOPD and could act as a predictor of AECOPD with PE.

[Interleukin-38 expression and clinical significance in serum of patients with chronic obstructive pulmonary disease]

Objective: To investigate the serum level of interleukin-38 (IL-38) and its clinical significance in patients with chronic obstructive pulmonary disease (COPD). Methods: Totally 72 patients with acute exacerbation of COPD (AECOPD group) and 65 patients with stable COPD (S-COPD group) were recruited from Tianjin Chest Hospital from June 2016 to August 2017. In the same period 40 elderly healthy subjects were selected as control group (C group). The general data and laboratory examination results of these subjects were recorded. Serum IL-38 was measured by double antibody enzyme-linked immunosorbent assays (ELISA). The inter-group differences of above parameters were analyzed. Pearson correlation or Spearman rank correlation analysis was used to analyze the correlation between IL-38 and each variable, and multivariate stepwise regression analysis was used to determine the influencing factors of serum IL-38 in COPD patients. Results: The serum level of IL-38 was higher in AECOPD group than in S-COPD group[(57.88±13.72) vs (51.75±14.06) ng/L, P<0.05], and was higher in either of the two COPD groups than in C group[(46.37±13.18) ng/L](both P<0.05). Correlation analysis of single factor showed that serum IL-38 levels were positively correlated with body mass index (r=0.190, P<0.05), and negatively correlated with C reactive protein (CRP), fibrinogen (FIB), forced expiratory volume in one second as a percentage of estimated value (FEV₁%pred) and the number of acute exacerbations in the past 1 year (r=-0.344, -0.176, -0.195, -0.229, all P<0.05). The CRP level and the number of acute exacerbations in the past 1 year were independent factors affecting the serum level of IL-38 (β=-0.204, -0.183, both P<0.05) in patients with COPD. Conclusion: IL-38 is compensatory increased in serum of patients with COPD and may be used as one of the serological markers for evaluation of COPD.

Giant Magneto-Impedance (GMI) Effect in Single-Layer Soft Magnetic Film Under Stress

The stress-induced magnetic anisotropy can significantly affect giant magneto-impedance (GMI) effect of the soft magnetic film. This paper is devoted to the GMI effect of the single layer soft magnetic film implied without and with a stress. By simulating a physical model with MATLAB and COMSOL software, the impedance expression of the single layer soft magnetic film and the relation between external magnetic field and magnetic permeability are deduced. We observed that, without a stress, the sensitive region increased firstly and then decreased with the increasing of the excitation current frequency from 1 MHz to 200 MHz. While the film was subjected to the stress in the direction of the current with one end stressed, the stress on the film was gradually reduced from stressed end to free end. Also, the impedance change rate of the film changed when the stress was added, which is similar to the effect of adding a bias magnetic field on the film. More importantly, the addition of stress σ can induce the bias of the GMI measurement range and improve its sensitivity near zero magnetic fields. This may provide a new way for designing a GMI sensor with higher sensitivity and adjustable measurement range.

[The association between blood pressure variability and sleep stability in essential hypertensive patients with sleep disorder]

Objective: To investigate the association of blood pressure variability and sleep stability in essential hypertensive patients with sleep disorder by cardiopulmonary coupling. Methods: Performed according to strict inclusion and exclusion criteria, 88 new cases of essential hypertension who came from the international department and the cardiology department of china-japan friendship hospital were enrolled. Sleep stability and 24 h ambulatory blood pressure data were collected by the portable sleep monitor based on cardiopulmonary coupling technique and 24 h ambulatory blood pressure monitor. Analysis the correlation of blood pressure variability and sleep stability. Results: In the nighttime, systolic blood pressure standard deviation, systolic blood pressure variation coefficient, the ratio of the systolic blood pressure minimum to the maximum, diastolic blood pressure standard deviation, diastolic blood pressure variation coefficient were positively correlated with unstable sleep duration (r=0.185, 0.24, 0.237, 0.43, 0.276, P<0.05). Conclusions: Blood pressure variability is associated with sleep stability, especially at night, the longer the unstable sleep duration, the greater the variability in night blood pressure.

Prognostic value of increased KPNA2 expression in some solid tumors: A systematic review and meta-analysis

Background

Karyopherin α2 (KPNA2), a member of the Karyopherin α family, has recently been reported to play an important role in tumor progression. However, the association between KPNA2 expression and prognosis in cancer remains controversial. So we performed this meta-analysis to evaluate whether expression of KPNA2 was associated with prognosis in patients with solid tumor.

Methods/Findings

24 published eligible studies, including 6164 cases, were identified and included in this meta-analysis through searching of PubMed, EMBASE and Web of Science. We found that KPNA2 expression was an independent predictor for the prognosis of solid tumor with primary outcome (overall survival [OS]: pooled HR=1.767, 95% CI=1.503-2.077, P<0.001) and secondary outcomes (time to recurrence [TTR], recurrence free survival [RFS] and progression free survival [PFS]). However, the association between KPNA2 overexpression and disease free survival [DFS] in solid tumors was not significant (pooled HR=1.653, 95% CI=0.903-3.029, P=0.104). Furthermore, the subgroup analysis revealed that KPNA2 overexpression was associated with poor OS in East-Asian patients and European patients, as well as patients with gastric and colorectal cancer.

Conclusion

KPNA2 expression may be a useful prognostic biomarker to monitor cancer prognosis. Further prospective studies with larger sample sizes are required to confirm our findings.

TMPRSS4 as an emerging potential poor prognostic factor for solid tumors: A systematic review and meta-analysis

Recent studies have investigated the potential prognostic value of the transmembrane protease serine 4 (TMPRSS4) in various solid tumors. Yet, the results are inconclusive. Here, we performed this meta-analysis to clarify this issue. Relevant articles were identified by searching PubMed, Web of Science and Embase databases. The primary outcome endpoints were patients' overall survival (OS) and time to tumor progression (TTP). Twelve studies involving 1,955 participants were included. We showed that high TMPRSS4 expression in tumor tissues was significantly associated with patients' poor OS (pooled HR = 2.981, 95% CI = 2.296-3.869, P < 0.001) and short TTP (pooled HR = 2.456, 95% CI = 1.744-3.458, P < 0.001). A subgroup analysis revealed that the association between TMPRSS4 and the outcome endpoints (OS or TTP) was also significant within China region. We conclude that TMPRSS4 overexpression in solid tumors is associated with patients' poor prognosis. TMPRSS4 could be a valuable prognosis biomarker or a promising therapeutic target of solid tumor.

Comparison of Radiotherapeutic Management of Operated Breast Cancer in 1999 and in 2006: A Sampling Survey on the Southeast Coast of China

Aims

To obtain a better understanding of the changes in radiotherapeutic management of breast cancer patients in the more developed areas of China over the past decade.

Methods

Four academic radiation therapy departments located on the Southeast Coast of China were selected for the study. The survey was conducted on female breast cancer patients who received radiotherapy in 1999 and 2006. The questionnaires were designed to determine the purposes of radiotherapy and to address the postoperative radiotherapy techniques used. The data for these two years were analyzed and compared.

Results

The percentage of breast-conserving treatment increased from 3% in 1999 to 13% in 2006, but the percentage of patients treated with postmastectomy radiotherapy dropped from 69% in 1999 to 66% in 2006 (P <0.05). As regards the changes in techniques from 1999 to 2006, the use of special immobilization devices, treatment planning systems, and CT simulations increased from 46% to 80%, 23% to 70%, and 0% to 14%, respectively (P <0.01). From 1999 to 2006, irradiation of the chest wall following mastectomy increased from 67% to 90%, but for internal mammary irradiation it decreased from 76% to 30% and for the axilla, from 69% to 37% (P <0.01). There were no obvious differences between 1999 and 2006 on the field design, boost treatment on the tumor bed, or dose prescription.

Conclusions

Breast-conserving treatment was performed more frequently in China in 2006 than in 1999, but postmastectomy radiotherapy did not change a great deal and it was still an essential option. Although the international treatment guidelines have been accepted and implemented by physicians in recent years, prompt improvement in the quality of breast cancer radiotherapy is needed.

[A review on group 2 innate lymphoid cells and miR-155 in allergic rhinitis]

Allergic rhinitis (AR) is the Th2 inflammatory response that atopic individuals exposure to allergens, mediators released by IgE-mediated, and a variety of immunocompetent cells and cytokines involved .Group 2 innate lymphoid cells (ILC2) are a novel population of native lymphocyte, can secrete large amounts of Th2 cytokines to promote the development of allergic diseases after being activated. MiR-155 plays a vital role in the development of the immune system, the differentiation of immune cells, and the maintenance of immune function.Nasal mucosas from the patients with allergic rhinitis show enrichment for ILC2 and miR-155. Highly expressed miR-155 may enhance the level of IL-4 by promoting ILC2 expression, thereby promoting Th2 inflammatory response.This review focuses on the function and meaning of ILC2 and miR-155 in patients with Allergic rhinitis.

[Epidemiological pattern of abnormal urinary fluoride rates in population with occupational fluoride exposure in Shanghai]

Objective: To investigate the epidemiological features of abnormal urinary fluoride rates in population with occupational exposure, and its relationships with age, work years and gender in Shanghai. Methods: A questionnaire survey was conducted respectively in 4 999 exposed workers and 283 non-exposed people during 2012-2015. Their urine samples were collected in plastic bottles and the fluoride ion selective electrode method was used for urinary fluoride level analysis. Logistic regression model was used to estimate associations between the abnormal rates and demographic/socioeconomic status of the study subjects. Results: In the past 4 years, the abnormal urinary fluoride rates (≥1.6 mg/L) in the population with occupational exposure was about 14.38%, it was about 1.43% in the control groups without occupational exposure. Their geometric mean of urinary fluoride content was 0.95 mg/L and 0.46 mg/L, respectively. The incidences of the abnormal rates in those aged ≥50 years and 34-39 years were 19.15% and 22.39%, respectively. The abnormal rate in males was 16.87%, much higher than that in females (6.85%). The abnormal rate had an upward trend along with the increased work years, especially in those with work years of ≥20 years. The abnormal rate was 23.28% in those with work years of ≥20 years and 13.29% in those with work years of <4 years. The relative risk for abnormal urinary fluoride rates was higher in male group, older age group and longer work year group, the odds ratio was 2.28, 1.10 and 1.13, respectively. Conclusions: Serious challenges exist in occupational health supervision. The relevant national standards should be updated as soon as possible. Males, those aged >50 years, and those with longer work years are the risk groups for intervention measures. More efforts are needed, such as strengthening the innovative application of health examination data and the equalization of basic public health service with comprehensive occupational health supervision programs among off-farm workers in the new medical reform.

Invasive pulmonary fungal infections in patients with connective tissue disease: a retrospective study from northern China

Invasive pulmonary fungal infection (IPFI) is a potentially fatal complication in patients with connective tissue disease (CTD). The current study aimed to uncover the clinical characteristics and risk factors of patients with IPFI-CTD. The files of 2186 CTD patients admitted to a single center in northern China between January 2011 and December 2013 were retrospectively reviewed. A total of 47 CTD patients with IPFI were enrolled into this study and assigned to the CTD-IPFI group, while 47 uninfected CTD patients were assigned to the control group. Clinical manifestations were recorded, and risk factors of IPFI were calculated by stepwise logistical regression analysis. Forty-seven (2.15%) CTD patients developed IPFI. Systemic lupus erythematosus patients were responsible for the highest proportion (36.17%) of cases with IPFI. Candida albicans (72.3%) accounted for the most common fungal species. CTD-IPFI patients had significantly elevated white blood cell count, erythrocyte sedimentation rate, C-reactive protein and fasting glucose values compared to controls (P<0.05). Cough, sputum and blood in phlegm were the most common symptoms. Risk factors of IPFI in CTD included maximum prednisone dose ≥30 mg/day within 3 months prior to infection, anti-microbial drug therapy, and interstitial pneumonia. CTD patients who have underlying interstitial pneumonia, prior prednisone or multiple antibiotics, were more likely to develop IPFI.

[Relationship between sleep architecture and blood pressure dynamic change in patients with sleep apnea syndrome]

OBJECTIVE

To investigate sleep architecture and blood pressure dynamic change in patients with Sleep apnea syndrome by electrocardiogram-based cardiopulmonary coupling analysis system.

METHODS

Seventy-nine sleep disorder participants (PSQI≥8) were enrolled. Electrocardiogram-based cardiopulmonary coupling analysis device and ambulatory blood pressure monitoring were synchronously used to evaluate sleep architecture and blood pressure circadian rhythm. The patients were divided into SAS group (47 participants) and non-SAS group (32 participants) according to the Apnea Hypopnea Index (AHI) that calculated by CPC device. The data of sleep architecture and blood pressure variability were compared between two groups.

RESULTS

Compared with non-SAS group, SAS group have less proportion of deep sleep, more proportion of light sleep, higher mean blood pressure in 24 hours and daytime, lower nocturnal blood pressure dipping, faster mean heart rate in night time (P<0.05). AHI has moderate inverse correlation with deep sleep time, wake/dream time (-0.6≤r<-0.3), moderate positive correlation with light sleep time (0.3<r≤0.6), high inverse correlation with nocturnal blood pressure dipping (r=-0.785, P=0.000), moderate positive correlation with mean diastolic blood pressure (r=0.425, P=0.019).

CONCLUSION

Our study shows that less proportion of deep sleep, more proportion of light sleep, 24 hours mean blood pressure and nocturnal blood pressure increase in the patients with Sleep Apnea Syndrome. The severity of Sleep Apnea Syndrome has a positive correlation with the severity of abnormal sleep architecture and the degree of blood pressure elevation.

Initial periodontal therapy for the treatment of gingival pregnancy tumor

The purpose of this study was to evaluate the clinical efficacy of initial periodontal therapy in gingival pregnancy tumors. Thirty-nine patients diagnosed with gingival tumors of pregnancy between 2007 and 2015 were enrolled in this study. The patients received initial periodontal therapy, then supportive periodontal therapies at 3- to 6-month intervals. The patients underwent follow up for 6 months to 8 years after treatment. After plaque control, supragingival scaling, and root planning, the tumors in 25 patients were gradually eliminated without the necessity of surgery. In 3 patients, tumors <5 mm in size disappeared in a mean time of 3.6 months, 4 patients with tumors 5-10 mm disappeared in a time of 7.5 months, 11 patients with tumors 10-15 mm disappeared in 10.2 months, 6 patients with tumors 15-20 mm disappeared in 15 months, and one patient with a tumor >20 mm disappeared in 20 months. No recurrence of gingival pregnancy tumors was noted during subsequent follow-up. Initial periodontal therapy combined with oral hygiene maintenance is efficacious in treating gingival pregnancy tumors of patients with normal hormone levels, which can potentially serve as an option to avoid surgery.

Evaluation of the Angiographic Grading Scale in Aneurysms Treated with the WEB Device in 80 Rabbits: Correlation with Histologic Evaluation

BACKGROUND AND PURPOSE

The WEB Occlusion Score has been proposed to assess angiographic outcomes for intracranial aneurysms treated with the Woven EndoBridge (WEB) device. Using a large series of experimental aneurysms treated with the WEB, we had the following objectives: 1) to compare angiographic outcomes as measured by the WEB Occlusion Scale with histologic results, and 2) to assess interobserver and intraobserver agreement of the WEB Occlusion Scale.

MATERIALS AND METHODS

Intracranial aneurysms were created in 80 rabbits and treated with WEB devices. Animals were sacrificed at last follow-up for histologic evaluation. DSA was performed just after the deployment of the device and at follow-up. Four investigators independently and retrospectively graded the DSA twice according to the WEB Occlusion Scale. One histopathologist blinded to the angiographic results graded the occlusion according to a 4-point scale patterned on the WEB Occlusion Scale. Intra- and interobserver agreement were evaluated for DSA. Follow-up angiographic grading and histologic reference were compared to determine the WEB Occlusion Scale accuracy for complete (with or without recess filling) versus incomplete occlusion and adequate (complete occlusion or neck remnant) versus inadequate occlusion.

RESULTS

Inter- and intraobserver weighted κ for the angiographic WEB Occlusion Scale were, respectively, 0.76 and 0.76, indicating substantial agreement. The sensitivity and specificity of the WEB Occlusion Scale for complete occlusion at follow-up compared with the histologic reference standard were, respectively, 75% and 83.3%, with an overall accuracy of 80%. Similarly, for adequate occlusion at follow-up, sensitivity was 97.7%, specificity was 64.9%, and overall accuracy was 82.5%.

CONCLUSIONS

The WEB Occlusion Scale appears to be consistent, reliable, and accurate compared with a histologic reference standard.

[Meta-analysis on epidemiology of iatrogenic-borne methicillin-resistant Staphylococcus aureus]

OBJECTIVE

To study the molecular-biologic characteristics and epidemiological status of iatrogenic related Community-acquired methicillin-resistant Staphylococcus (S.) aureus (CA-MRSA) in China through Meta-analysis.

METHODS

Data through systematic searching for peer-reviewed articles published before December 3(rd), 2015 from 4 main electronic databases including China National Knowledge Infrastructure (CNKI), Wanfang Data, PubMed and Web of Science Core Collection was collected, for this Meta-analysis. PRISMA guidelines were followed and the proportion of MRSA, CA-MRSA, hospital-acquired MRSA (HA-MRSA) and panton-valentine leucocidin (PVL) gene in certain populations were quantitatively analyzed by Stata 13.0 software.

RESULTS

Average proportion of CA-MRSA from S. aureus was 12% (95%CI: 8%-16%). CA-MRSA in MRSA was 18% (95%CI: 12%-24%). 42.1% (95%CI: 20.4%-63.7%) of the CA-MRSA carried a PVL gene, and the number was higher than general MRSA (t=-2.99,P=0.011).

CONCLUSION

CA-MRSA was in lower proportion than HA-MRSA, both seen in general MRSA and in S. aureus, but under higher proportion of carrying the PVL gene. Transmission of CA-MRSA could be prevented within the general population through conducting effective surveillances and preventive programs.

Self-Assemblies of Acicular Hollow Fe/C Nanostructures

Self-assemblies of acicular hollow Fe/C structures were synthesized using D-glucose monohydrate and ferric chloride as precursors by a simple hydrothermal process followed by carbonization at 800 °C. The self-assembled structures with an overall diameter of 15~20 µm composed of radially formed hollow needles from a central core with an average diameter of ca. 1 µm and a length up to 10 µm. The end of the needles was revealed to be a awl shape with a hollow structure formed during the self-assembly process and the subsequent heat treatment. The hollow structure was probably caused by the Kirkendall effect at 800 °C. The materials exhibit ferromagnetic characteristic with saturation magnetization (Ms), remanent magnetization (Mr), and coercivity (Hc) of 22.2 emu/g, 3 emu/g, and 151.22 Oe, respectively, with Ms much lower than that of Fe3O4.

MicroRNA-101 down-regulates sphingosine kinase 1 in colorectal cancer cells

MicroRNAs (miRs) dysregulation is a general feature of colorectal cancer (CRC) and other solid tumors, and is associated cancer progression. In the current study, we demonstrate that microRNA-101 (miR-101) inhibits CRC cells probably through down-regulating sphingosine kinase 1 (SphK1). Our results showed that exogenously expressing miR-101 inhibited CRC cell (HT-29 and HCT-116 lines) growth in vitro. At the molecular level, miR-101 dramatically down-regulated SphK1 mRNA and protein expression, causing pro-apoptotic ceramide production in above CRC cells. On the other hand, inhibition of miR-101 through expressing antagomiR-101 increased SphK1 expression to down-regulate ceramide level in HT-29 cells. miR-101 expression increased the in vitro anti-CRC activity of conventional chemo-agents: paclitaxel and doxorubicin. CRC cells with SphK1-shRNA knockdown showed similar phenotypes as the miR-101-expressed CRC cells, presenting with elevated level of ceramide and high sensitivity to paclitaxel or doxorubicin. In vivo, HCT-116 xenograft growth in severe combined immuno-deficient (SCID) mice was dramatically inhibited by over-expressing miR-101. Further, miR-101 enhanced paclitaxel-induced anti-HCT-116 activity in vivo. Together, these results indicate that miR-101 exerts its anti-CRC activities probably through down-regulating SphK1.

Systemic analysis on risk factors for breast cancer related lymphedema

BACKGROUND

To evaluate risk factors for upper extremity lymphedema due to breast cancer surgery.

MATERIALS AND METHODS

Clinical studies published on PubMed, Ovid, EMbase, and Cochrane Library from January 1996 to December 2012 were selected.

RESULTS

Twenty-five studies were identified, including 12,104 patients. Six risk factors related to the incidence of lymphedema after breast cancer treatment were detected: axillary lymph node dissection (OR=3.73, 95%CI 1.16 to 11.96), postoperative complications (OR=2.64, 95%CI 1.10 to 6.30), hypertension (OR=1.83, 95%CI 1.38 to 2.42), high body mass index (OR=1.80, 95%CI 1.30 to 2.49), chemotherapy (OR=1.38, 95%CI 1.07 to 1.79) and radiotherapy (OR=1.35, 95%CI 1.10 to 1.66). We found significant protective factors for lymphedema: pathologic T classification (OR=0.57, 95%CI 0.36 to 0.91) and stage (OR=0.60, 95%CI 0.39 to 0.93), while some factors, like age, number of positive lymph nodes, number of lymph node dissection, demonstrated no obvious correlation.

CONCLUSIONS

Axillary lymph node dissection, postoperative complications, hypertension, body mass index, chemotherapy, radiotherapy are risk factors for lymphedema after breast cancer treatment. Attention should be paid to patients with risk factors to prevent the occurrence of lymphedema.

Confirmation of soybean plastid rRNAs by formaldehyde denaturing agarose gel electrophoresis

Owing to their prokaryotic origin, plastid rRNAs are mainly 23s/16s/5s rRNAs. We present a novel plant RNA isolation method in this paper. Also, not only the eukaryotic 28s (26s, 25s)/18s rRNAs but the prokaryotic 26s/23s rRNAs as well were demonstrated in a single sample for the first time by formaldehyde denaturing agarose gel electrophoresis.

Association of dietary intake of folate and MTHFR genotype with breast cancer risk

We conducted a hospital-based case-control study to investigate the associations of dietary intake of folate and MTHFR C677T and A1298C polymorphisms with breast cancer in a Chinese population. A 1:1-matched case-control study was conducted. Two hundred and thirty patients who were newly diagnosed and histologically confirmed breast cancer and 230 controls were enrolled from Xinxiang Central Hospital. Folate intake was calculated by standard portion size and relative size for each food item in the questionnaire. Genotyping of MTHFR C677T and A1298C was performed by PCR-RFLP. MTHFR 677TT (OR = 2.26, 95%CI = 1.09-4.87, P = 0.02) and T allele (OR = 1.40, 95%CI = 1.03-1.90, P = 0.03) had an increased risk of laryngeal cancer when compared with the CC genotype. We found any interaction between MTHFR C677T and folate intake (P for interaction = 0.02). In conclusion, our study demonstrated that MTHFR C677T polymorphism and folate are associated with risk of breast cancer.

Copy number variation at 6q13 is associated with lung cancer risk in a Han Chinese population

Copy number variations (CNVs), a major source of human genetic polymorphism, have been suggested to have an important role in genetic susceptibility to common diseases such as cancer, immune diseases, and neurological disorders. Lung cancer is a multifactorial tumor closely associated with genetic background. Previous genome-wide association studies have identified single nucleotide polymorphisms (SNPs) that are associated with lung cancer susceptibility. This study examined the CNVR2966.1 at 6q13 and its association with lung cancer susceptibility. The CNVR2966.1 was found to be a 10,379 bp nucleotides deletion/insertion within the uniform boundaries chromosome 6: 74,648,791-74,659,169. The risk of lung cancer observed in 503 cases and 623 controls was significantly associated with copy number of CNVR2966.1, with the odds ratio (OR) being 1.38 [95% confidence interval (CI) = 1.05-1.79; P = .007] for one copy genotype compared with two copies genotype. These results suggest that CNVR2966.1 is associated with lung cancer risk.

A generic plant RNA isolation method suitable for RNA-Seq and suppression subtractive hybridization

A recently developed revolutionary approach to transcriptomics, RNA-Seq, and suppression subtractive hybridization are powerful tools for gene expression research. However, currently, the difficulty of isolating high-quality RNAs from plant tissues bearing abundant complex polysaccharides, polyphenolics, and secondary metabolites is a serious problem that not only limits the application of these technologies but also hinders studies dealing with RNA in general. We have developed a consistent protocol to prepare highly intact and pure RNAs from tissues of a variety of field-grown plant species, with high yields, in 2 to 3 h. Additionally, this method can be readily applied to mammalian, yeast, and bacterial cells.

Biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent placement to reduce fibroblast proliferation in experimental stricture in a canine model

BACKGROUND AND STUDY AIMS

The aim of the current study was to assess whether placement of the biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent is followed by less fibroblast proliferation and tissue hyperplasia compared with bare stents in experimental stricture in a dog model.

METHODS

A total of 80 dog models of stricture were randomly divided into a control group (n = 20, no stent insertion), a bare stent group (BSG, n = 20, 1-week retention), and two drug-eluting stent sub-groups (DESG-1w, n = 20, 1-week retention; DESG-4w, n = 20, 4-week retention). Lower esophageal sphincter (LES) pressure, 5-minute barium height (5-mBH), and cardia diameter were assessed before, immediately after the procedure, and regularly thereafter for 6 months. Five dogs in each group were euthanized for histological examination at each follow-up assessment.

RESULTS

Stent insertion was well tolerated, with similar migration rates (0 % in BSG vs. 7.5 % in DESGs; P = 0.5441). At 6 months, LES pressure and 5-mBH improved in DESG-1w (26.70 ± 5.02 mmHg and 6.50 ± 2.98 cm) and DESG-4w (20.16 ± 5.50 mmHg and 1.54 ± 0.98 cm) compared with BSG (39.94 ± 5.22 mmHg and 11.1 ± 5.46 cm) (P < 0.05), with DESG-4w being more stable than DESG-1w (P < 0.05). The cardia maintained greater patency in the DESGs (7.10 ± 3.09 mm in DESG-1w; 9.16 ± 3.77 mm in DESG-4w) than in the BSG (1.86 ± 2.45 mm; P < 0.05). Reduced peak inflammatory reactions and scarring occurred in DESGs compared with the BSG (P < 0.05), with a better outcome in DESG-4w than in DESG-1w (P < 0.05).

CONCLUSIONS

In this experimental stricture model, rapamycin-eluting stents were more effective than bare stents for the reduction of fibroblast proliferation and tissue hyperplasia after stent placement. Furthermore, 4-week retention of the drug-eluting stent led to a better outcome than 1-week retention.

Value of TP53 status for predicting response to neoadjuvant chemotherapy in breast cancer: a meta-analysis

Background

Numerous studies have yielded inconclusive results regarding the relationship between tumor suppressor protein TP53 overexpression and/or TP53 gene mutations and the response to neoadjuvant chemotherapy in patients with breast cancer. The purpose of the current study was therefore to evaluate the relationship between TP53 status and response to chemotherapy in breast cancer.

Methods and Findings

A total of 26 previously published eligible studies including 3,476 cases were identified and included in this meta-analysis. TP53 status (over expression of TP53 protein and/or TP53 gene mutations) was associated with good response in breast cancer patients who received neoadjuvant chemotherapy (total objective response: risk ratio [RR]  = 1.20, 95% confidence interval [CI]  = 1.09–1.33, p<0.001; pathological objective response: RR = 1.37, 95% CI = 1.20–1.57, p<0.01; total complete response: RR = 1.33, 95% CI = 1.15–1.53, p<0.001; pathological complete response: RR = 1.45, 95% CI = 1.25–1.68, p<0.001). In further stratified analyses, this association also existed among the studies using anthracycline-based neoadjuvant chemotherapy, and the association between response and the presence of gene alterations was stronger than that between response and immunohistochemistry positivity.

Conclusion

The results of the present meta-analysis suggest that TP53 status is a predictive factor for response in breast cancer patients undergoing neoadjuvant chemotherapy. Further larger and well-designed prospective studies are required to evaluate the predictive role of TP53 status in clinical practice.

Novel nanoscale architectures: coated nanotubes and other nanowires

Research has demonstrated that the structure and properties of a nanoscale system are inextricably linked. The advent of nanoscale research in 1991 relied upon nanoscale material production through random formation techniques, such as arc discharge, and the inherent properties and morphology of the system were therefore difficult to control. This article reviews some of the methods and ideas that have developed since the inception of nanotechnology, leading to fine control over the morphology of nanoscale systems and highlighting some interesting nanoscale architecture.

[Establishing a FEM of mandibular first molar and stress analysis]

OBJECTIVE

Establishing a finite element model of mandibular first molar with analysis of the stress distribution to each of the tooth parts on the model.

METHODS

The right mandibular first molar in vitro was scanned and the image was processed. The three dimensional finite-element model was established by the special software and loaded on it.

RESULTS

Stress distribution on each part of the tooth was obtained. The maximum values of compressive stress, tensile stress and mises stress were calculated.

CONCLUSION

In the research and analysis of the tooth stress, the finite element method is simple, effective, safe and reliable.

Carbon nanotube template promoted growth of NbS2 nanotubes/nanorods

NbS2 nanotubes/rods have been generated successfully employing carbon nanotube template promoted growth; high resolution transmission electron microscopy, coupled with EDX analysis, confirm the template effect and existence of NbS2 tube structures.

[Experimental study on apical sealing ability of Sankin hydroxyapatite root canal sealer]

OBJECTIVE

To compare the apical sealing ability of Sankin hydroxyapatite root canal sealer with traditional root canal sealers.

METHODS

Determination of the length of apical dye leakage by methylene leakage test.

RESULTS

The length of apical dye leakge of Sankin hydroxyapatite root canal sealer was 2.40 mm, that of iodoform paste and zinc oxide eugenol paste was 4.37 mm and 5.80 mm,respectively. There was no significant difference between iodoform paste and zinc oxide-eugenol paste (P>0.05);whereas there was significant difference between Sankin hydroxyapatite root canal sealer and iodoform paste or zinc oxide eugenol paste(P<0.01).

CONCLUSION

Sankin hydroxyapatite root canal sealer has better apical sealing ability than traditional root canal sealers.

Characterization of a Pseudomonas aeruginosa efflux pump contributing to aminoglycoside impermeability

Pseudomonas aeruginosa can employ many distinct mechanisms of resistance to aminoglycoside antibiotics; however, in cystic fibrosis patients, more than 90% of aminoglycoside-resistant P. aeruginosa isolates are of the impermeability phenotype. The precise molecular mechanisms that produce aminoglycoside impermeability-type resistance are yet to be elucidated. A subtractive hybridization technique was used to reveal gene expression differences between PAO1 and isogenic, spontaneous aminoglycoside-resistant mutants of the impermeability phenotype. Among the many genes found to be up-regulated in these laboratory mutants were the amrAB genes encoding a recently discovered efflux system. The amrAB genes appear to be the same as the recently described mexXY genes; however, the resistance profile that we see in P. aeruginosa is very different from that described for Escherichia coli with mexXY. Direct evidence for AmrAB involvement in aminoglycoside resistance was provided by the deletion of amrB in the PAO1-derived laboratory mutant, which resulted in the restoration of aminoglycoside sensitivity to a level nearly identical to that of the parent strain. Furthermore, transcription of the amrAB genes was shown to be up-regulated in P. aeruginosa clinical isolates displaying the impermeability phenotype compared to a genotypically matched sensitive clinical isolate from the same patient. This suggests the possibility that AmrAB-mediated efflux is a clinically relevant mechanism of aminoglycoside resistance. Although it is unlikely that hyperexpression of AmrAB is the sole mechanism conferring the impermeability phenotype, we believe that the Amr efflux system can contribute to a complex interaction of molecular events resulting in the aminoglycoside impermeability-type resistance phenotype.

Seven novel methylation guide small nucleolar RNAs are processed from a common polycistronic transcript by Rat1p and RNase III in yeast

Through a computer search of the genome of the yeast Saccharomyces cerevisiae, the coding sequences of seven different box C/D antisense small nucleolar RNAs (snoRNAs) with the structural hallmarks of guides for rRNA ribose methylation have been detected clustered over a 1.4-kb tract in an inter-open reading frame region of chromosome XIII. The corresponding snoRNAs have been positively identified in yeast cells. Disruption of the nonessential snoRNA gene cluster specifically suppressed the seven cognate rRNA ribose methylations but did not result in any growth delay under the conditions of yeast culture tested. The seven snoRNAs are processed from a common polycistronic transcript synthesized from an independent promoter, similar to some plant snoRNAs but in marked contrast with their vertebrate functional homologues processed from pre-mRNA introns containing a single snoRNA. Processing of the polycistronic precursor requires nucleases also involved in rRNA processing, i.e., Rnt1p and Rat1p. After disruption of the RNT1 gene, the yeast ortholog of bacterial RNase III, production of the seven mature snoRNAs was abolished, while the polycistronic snoRNA precursor accumulated. In cells lacking functional Rat1p, an exonuclease involved in the processing of both pre-rRNA and intron-encoded snoRNAs, several processing intermediates of the polycistronic precursor accumulated. This allowed for the mapping in the precursor of the presumptive Rnt1p endonucleolytic cuts which provide entry sites for subsequent exonucleolytic trimming of the pre-snoRNAs. In line with known properties of double-stranded RNA-specific RNase III, pairs of Rnt1p cuts map next to each other on opposite strands of long double-helical stems in the secondary structure predicted for the polycistronic snoRNA precursor.

[Effect on preparing curved artificial root cancals with five handle endodonic instruments I.comparison of cutting ability]

OBJECTIVE: To compare the cutting ability of five handle endodontic instruments. METHODS: The speciments weight loss following serial preparation of artificial root canal were measured with electronic analysis balance. RESULTS: The greatest cutting ability occurred with H file,then with K-flex file,Unifile,K file and K reamer. CONCLUSION: The cutting ability of endodontic instrument is influenced by several factors,such as metallurgical properties,cross-sectional configuration of shaft,flute design and tip design.

[Effect on preparing curved artificial root canal with five handle endodontic instruments II comparision of shaping ability]

OBJECTIVE:To compared the shaping ability of five handle endodontic instruments. METHODS: The canal shape of prepared artificial root canals with five handle endodontic instruments were observed by light-microscope. RESULTS: Apical zips,elbows and perforations were not found. Ledges occurred in speciments of K-Flex group and they were relating to resinous plugs.The apical transportatins were relating to resinous plugs.The apical transportations of K-Flex group and H file group are much greater than other groups. CONCLUSION: Unifile or K file is first choice to prepare curved artificial root canals with routine preparation technique by comprehensive evaluaion of the cutting ability and shaping ability of five handle endodontic instruments.

The 16-kDa alpha-crystallin (Acr) protein of Mycobacterium tuberculosis is required for growth in macrophages

Although the 16-kDa alpha-crystallin homologue of Mycobacterium tuberculosis (MTB) is the dominant protein produced by stationary phase cultures in vitro, it is undetectable in logarithmically growing cultures. By growing bacilli at defined oxygen concentrations, acr transcription was shown to be strongly induced by mildly hypoxic conditions. Acr expression also was found to be induced during the course of in vitro infection of macrophages. The acr gene was replaced with a hygromycin resistance cassette by allelic exchange in MTB H37Rv. The resulting Deltaacr::hpt strain was shown to be equivalent to wild-type H37Rv in in vitro growth rate and infectivity but was significantly impaired for growth in both mouse bone marrow derived macrophages and THP-1 cells. In addition to its proposed role in maintenance of long-term viability during latent, asymptomatic infections, these results establish a role for the Acr protein in replication during initial MTB infection.

[A study of the shape of prepared canal of commonly used hand endodontic instruments]

OBJECTIVE:Straight or slightly curved single root canals of teeth (<20 degree) were instrumentated with three commonly the hand endodontic instruments,which included K reamer,K file and H filel.The shape of prepared canal and root canal deviation at three levels were measured by computerized digital image processing program.The results demostrated that any significant differences were not found on root canal deviation in either labio-lingual or mesiodistal direction at each level,and that the shape of prepared canal was not different significantly.Apical transportation of the severely curved artificial root canals(25-30 degree) showed that H file was the most severe,K reamer was the least.It is suggested in this article how we select endodontic instruments rationally and effectively.

Pharmacokinetics of bendazac lysine in 10 Chinese young men

AIM

To compare the pharmacokinetics of domestic and imported tablets of bendazao lysine (BL).

METHODS

A single oral dose of 500 mg BL of this 2 kinds of tablets was given to 10 Chinese volunteers of Han nationality in a randomized crossover study. Plasma levels were determined with HPLC-UV method. Data were analyzed automatically by using a CAPP program on microcomputer.

RESULTS

The plasma concentration-time curve was fitted to 2-compartment open model, and the major pharmacokinetic parameters of domestic and imported BL tablets were shown respectively as following: Cmax 66 +/- 16 and 65 +/- 8 mg.L-1; Tmax 0.98 +/- 0.22 and 0.98 +/- 0.21 h; T1/2 beta 6.2 +/- 1.8 and 6.2 +/- 1.7 h; AUC 335 +/- 47 and 337 +/- 58 mg.h.L-1. There was no significant difference between domestic and imported tablets. The bioavailability of the domestic vs that of the imported tablet was 99 +/- 12%. The unchanged BL in urine were about 5.4% and 5.6% respectively of the dosage in 24 h after a single oral dose.

CONCLUSION

The two kinds of tablets had the same biological effects.

Mutants of feline immunodeficiency virus resistant to 2',3'-dideoxy-2',3'-didehydrothymidine

We selected mutants of feline immunodeficiency virus (FIV) that are resistant to 2',3'-dideoxy-2',3'-didehydrothymidine (d4T). Two mutants were selected in cultured cells with a stepwise increase in d4T concentration, resulting in mutants able to replicate in 100 microM d4T. These mutants were three- to sixfold more resistant to d4T than wild-type FIV. They were also cross-resistant to 3'-azido-3'-deoxythymidine (AZT), 3'-fluoro-2',3'-dideoxythymidine, 2',3'-dideoxycytidine, 2',3'-dideoxyinosine, and 9-(2-phosphonylmethoxyethyl)adenine, and they were highly resistant to phosphonoformic acid (PFA). Plaque-purified mutants were isolated from each of the mutant populations. The mutant phenotype was stable, because both of the plaque-purified mutants remained d4T resistant even after three passages in the absence of d4T. One of the plaque-purified mutants, designated D4R-3c, was further characterized. Compared with wild-type reverse transcriptase (RT), RT purified from D4R-3c was 3-fold resistant to inhibition by the 5'-triphosphate of d4T, 10-fold resistant to inhibition by the 5'-triphosphate of AZT, and 6-fold resistant to PFA. D4R-3c had a single point mutation in the RT-encoding region of the pol gene at position 2474, resulting in a Val to Ile mutation at codon 47 of the FIV RT. The role of this mutation in d4T resistance was confirmed by site-directed mutagenesis.