The diagnostic values of multicolor melting curve analysis on drug resistance to 5 anti-tuberculosis drugs / 中国热带医学

@#Abstract: Objective To explore and analyze the diagnostic value of multicolor melting curve analysis (MMCA) for the resistance of five anti-tuberculosis drugs, so as to clarify the clinical value of MMCA in detecting drug resistance of Mycobacterium tuberculosis. Methods From April 2021 to May 2022, 200 patients with positive Mycobacterium tuberculosis admitted to the Fourth People's Hospital of Qinghai Province were selected as research objects, and sputum specimens were taken from the patients. Traditional Mycobacterium tuberculosis drug sensitivity test (modified Löwenstein-Jensen medium method) and MMCA analysis were respectively given to detect the resistance of five anti-tuberculosis drugs, including isoniazid, ethambutol, streptomycin, rifampicin and isoniazid, respectively. Those samples with inconsistent results between the two diagnosis methods were subjected to gene sequencing verification, and the diagnosis efficiency of MMCA for the five anti-tuberculosis drugs was compared. Results Using Mycobacterium tuberculosis drug sensitivity as the gold standard for drug resistance diagnosis, the sensitivity of MMCA for detecting drug resistance of rifampicin, ethambutol, streptomycin, isoniazid and levofloxacin were 95.83% (46/48), 93.75% (15/16), 100.00% (15/15), 100.00% (20/20) and 70.00% (7/10), respectively, with statistical differences between groups (P<0.05). There were no statistically significant differences in the specificity, positive predictive value, negative predictive value and accuracy of MMCA for the five anti-tuberculosis drugs (P>0.05). For the 8 samples with inconsistent results between MMCA and modified Löwenstein-Jensen medium method, gene sequencing was performed and compared with the results of gene sequencing. After comparison with gene sequencing results, it was found that the coincidence rate of MMCA and gene sequencing results was 75.00% (6/8). Conclusions In the detection of drug-resistant mutations in TB patients, multi-color probe fusion curve analysis has high diagnostic efficacy for first-line anti-tuberculosis drugs, but is not sensitive to second-line anti-tuberculosis drug levofloxacin. Therefore, for the detection of first-line anti-tuberculosis drugs, MMCA has a good clinical application prospect.

Repair impact of vibration exercise with different frequencies on articular cartilage of rats with early knee osteoarthritis and its JNK/NF-κB, SOX9 mechanisms / 中国应用生理学杂志

Objective: To investigate the repair effect and JNK/NF-κB,SOX9 mechanisms of vibration exercise with different frequencies on articular cartilage in rats with early knee osteoarthritis. Methods: Forty-eight adult male SD rats were randomly divided into six groups(n=8):model control group(MC),high frequency vibration group 1 (GP1,60 Hz),high frequency vibration 2 group (GP2,40 Hz),medium frequency vibration group (ZP,20 Hz),minor frequency group(DP,10 Hz)and normal control group(NC). Except for NC group,the rats in each group were made into early knee osteoarthritis model after six weeks of knee joint cavity injection of papain solution and 2% mixture l-cysteine on the 1st,4 th and 7th day. Each exercise group was subjected vibration to 40 minutes a day with amplitude of 2～5 mm and 5 days a week. Four weeks later, the articular cartilage of the lateral femoral condyle of the both back leg knee joints were detected by HE staining,serine O staining and Mankin scores for morphological observation. The expression levels of JNK,NF-κB p65 and Sox9 mRNA in articular cartilage of the medial femoral condyle were detected by RT-qPCR,and the protein expressions of JNK,NF-κB p65 and Sox9 were detected by Western blot. Results: Compared with the NC group,the Mankin score in other groups was significantly higher (P＜0.01). Compared with the MC group,the Mankin score of each vibration group was significantly lower(P＜0.05),the mRNA and protein expressions of JNK and NF-κB p65 in each vibration training group were significantly lower (P＜0.01),the expressions of Sox9 mRNA and protein in vibration training group were increased significantly (P＜0.01). Compared with the higher frequency group,the Mankin score,the mRNA and protein expressions of JNK and NF-κB p65 of lower frequency group were significantly lower (P＜0.05 or P＜0.01). But the expressions of Sox9 mRNA and protein were significantly higher (P＜ 0.05 or P＜0.01). Conclusion: Vibration exercise of different frequencies may present varying degrees of cartilage repair impact in rats with early knee osteoarthritis,and the cartilage repair by low-frequency vibration training is better than that by high-frequency vibration. This can be one of the mechanisms on controlling collagen synthesis by down-regulating JNK/NF-κB expression and increasing SOX9 activity of OA articular cartilage.

Effects of Different Routes in PMSC Transfusion on the Levels of Hematopoietic Regulatory Factors in Aplastic Anemia Rats / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of different routes in placental mesenchymal stem cells (PMSC) on serum expression levels of IL-4, IL-17, TNF-α and IFN-γ in aplastic anemia (AA) rats.@*METHODS@#The rat model of aplastic anemia (AA rats) was established by 5-fluorouracil combined with busulfan. The rats was divided into four groups: control, experimental, PMSC-injected into the tail vein, and PMSC-injected into the medullary cavity. The general state of rats in each group was observed in detail before and after treatment. The serum levels of interleukin-4 (IL-4) , interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) were measured by enzyme-linked immunosorbent assay (ELISA) at week 1, 3 and 5 after treatment.@*RESULTS@#The serum levels of TNF-α, IFN-γ and IL-17 in the experimental group were significantly higher than those in the control group, while the level of IL-4 was significantly decreased (P＜0.05). The levels of TNF-α, IFN-γ and IL-17 gradually decreased after treatment while the level of IL-4 increased. By the fifth week, the above indexes were closed to the control group (P＞0.05), and the levels of TNF-α, IFN-γ and IL-17 in the group with PMSCs injected via the medullary cavity decrease more significantly than those group with PMSC injected via the tail vein, but level of IL-4 was not significantly different between two groups.@*CONCLUSION@#The level of serum hematopoietic negative regulators increase significantly, and the level of hematopoietic promoting factors decreases significantly in aplastic anemia rats. PMSC can down-regulate the level of hematopoietic negative regulators and up-regulate the level of hematopoietic promoting factors in the rats with aplastic anemia, and the inhibition of hematopoietic negative regulators by intramedullary injection is more significant than that by caudal vein injection.

Differentiating gastric cancer and gastric lymphoma using texture analysis (TA) of positron emission tomography (PET) / 中华医学杂志(英文版)

BACKGROUND@#Texture analysis (TA) can quantify intra-tumor heterogeneity using standard medical images. The present study aimed to assess the application of positron emission tomography (PET) TA in the differential diagnosis of gastric cancer and gastric lymphoma.@*METHODS@#The pre-treatment PET images of 79 patients (45 gastric cancer, 34 gastric lymphoma) between January 2013 and February 2018 were retrospectively reviewed. Standard uptake values (SUVs), first-order texture features, and second-order texture features of the grey-level co-occurrence matrix (GLCM) were analyzed. The differences in features among different groups were analyzed by the two-way Mann-Whitney test, and receiver operating characteristic (ROC) analysis was used to estimate the diagnostic efficacy.@*RESULTS@#InertiaGLCM was significantly lower in gastric cancer than that in gastric lymphoma (4975.61 vs. 11,425.30, z = -3.238, P = 0.001), and it was found to be the most discriminating texture feature in differentiating gastric lymphoma and gastric cancer. The area under the curve (AUC) of inertiaGLCM was higher than the AUCs of SUVmax and SUVmean (0.714 vs. 0.649 and 0.666, respectively). SUVmax and SUVmean were significantly lower in low-grade gastric lymphoma than those in high grade gastric lymphoma (3.30 vs. 11.80, 2.40 vs. 7.50, z = -2.792 and -3.007, P = 0.005 and 0.003, respectively). SUVs and first-order grey-level intensity features were not significantly different between low-grade gastric lymphoma and gastric cancer. EntropyGLCM12 was significantly lower in low-grade gastric lymphoma than that in gastric cancer (6.95 vs. 9.14, z = -2.542, P = 0.011) and had an AUC of 0.770 in the ROC analysis of differentiating low-grade gastric lymphoma and gastric cancer.@*CONCLUSIONS@#InertiaGLCM and entropyGLCM were the most discriminating features in differentiating gastric lymphoma from gastric cancer and low-grade gastric lymphoma from gastric cancer, respectively. PET TA can improve the differential diagnosis of gastric neoplasms, especially in tumors with similar degrees of fluorodeoxyglucose uptake.

Drinking water current situation among Guanzhong area rural primary and secondary schools in 2018 / 中国学校卫生

Objective@#To investigate and analyze the drinking water quality among rural primary and secondary schools in Guanzhong area in 2018, and to provide a basis for the targeted improvement of water supply facilities.@*Methods@#Develop a questionnaire on the basic situation of centralized water supply in rural schools, according to the Standard Test Method for Drinking Water (GB/T 5750—2006) and the Sanitary Standard for Drinking Water (GB 5749—2006) for the rural school network in Guanzhong area. The peripheral water collection and testing carried out single factor and multifactor statistical analysis on the relationship between water quality influencing factors and water quality pass rate.@*Results@#The total qualified rate of drinking water quality in rural schools in Guanzhong area was 59.1%. Univariate analysis showed that water quality rate was affected by four factors including water source type, engineering type, sanitation permit and disinfection equipment use, and the difference was statistically significant(P<0.05). Unconditional two-class logistic regression analysis showed that disinfection (OR=3.14), engineering type (OR=2.05), and sanitation permit (OR=1.99)(P<0.05) affected the water quality pass rate.@*Conclusion@#It is recommended to further strengthen the investment in the renovation of water supply for rural schools in Guanzhong area, and specifically strengthen water supply treatment and standard disinfection.

Kennedy disease: A case report and a systemic review of research in China / 第二军医大学学报

Objective To report a case of Kennedy disease confirmed by gene diagnosis and to retrospectively reviewed the clinical features of genetically-confirmed patients with Kennedy disease in China. Methods The clinical data of this patient from our hospital were collected. Two electronic databases (Wanfang Data and CNKI) were searched using keywords “Kennedy disease” and “X-linked recessive hereditary amyotrophy of spinal cord and medulla oblongata” from Jan. 2007 to Dec. 2017. And a total of 63 articles (170 cases) were finally identified, including one case reported by us. The clinical data and biochemical indicators of Kennedy disease in China were summarized and analyzed. Results All the 170 patients were male. The average age of onset was (39.12±10.21) years old in 164 patients with described age of onset, mainly ranging 30-50 years old, and the average age of treatment was (48.04±8.94) years. We also noticed that the age of onset was negatively correlated with the number of CAG repeats in 161 patients (r＝－0.272, P＝0.001). In 170 Kennedy disease patients, the most common symptoms were proximal weakness of the lower extremities (93 cases, 54.71%), followed by weakness of limbs (38 cases, 22.35%). With the progression of the disease, 93 (54.71%) patients had breast development and/or decreased sexual function; and 143 (84.12%) patients had atrophy and fibrillation of tongue muscles, but no obvious drinking water choking was found in the literature. The main signs of lower motor neuron were mild muscle atrophy, fascicular fibrillation, mild muscle degeneration, especially the proximal limb, with diminished or disappeared tendon reflex. We also noticed that 91.18% (155/170) of the patients had increased creatine kinase. Some patients had diabetes, elevated blood lipids, thyroid dysfunction and/or mild liver dysfunction. Conclusion The diagnosis of suspected Kennedy disease patients can be confirmed by genetic tests with the deep understanding of the disease by physicians and the popularization of genetic examination, although there have been no effective methods for treatment of Kennedy disease.

Drinking water and toilet sanitation of rural primary schools and middle schools in the northern，southern and central regions of Shaanxi during 2016-2018 / 中国学校卫生

Objective@#To understand the environmental sanitation situation of rural schools in different geographical areas of Shaanxi, and to provide scientific basis for improving hygiene and sanitation in Chinese rural schools.@*Methods@#Each year during 2016 to 2018, 150 townships in 30 counties of rural areas were randomly selected in various districts and cities throughout the province. In each township one junior high school and one elementary school were randomly selected, and the data was obtained through resource access, interviews, and on-site observations. The data was statistically analyzed and evaluated according to the northern, central and southern regions.@*Results@#The differences of drinking ways among students in the schools were of statistical significance(χ2=25.89,P<0.01). The major drinking water method of students in the monitoring schools of the three regions all was providing boiled water, accounting for 56.16%, 65.88%, 50.39%, all of which have direct drinking unboiled water phenomenon; The water supply method of the self-provided centralized water supply school is mainly precipitation filtration in the central and southern regions, accounting for 38.46%, 53.21%, and untreated in the northern region(60.61%); The differences of the proportions of having sanitary toilets, detached toilets in schools, having toilets in teaching buildings, and having toilets in dormitory buildings in three regions were of statistical significance(χ2=32.04, 12.73, 20.78, 33.11, P<0.01) The proportion of schools with squat toilets in men’s toilets was greater than that of women’s(χ2=86.53, 44.77, 21.88, P<0.01). The differences of the proportion of schools with faucets available in toilets and within 5 meters around toilets, with sinks in or around the toilets, with sinks equipped with soap in or around the toilets were of statistical significance(χ2=90.02, 10.40, 41.96, P<0.01).@*Conclusion@#During 2016 to 2018, the environment sanitation of the three major rural primary and middle schools in Shaanxi Province needs to improve corresponding supporting facilities, and increase publicity to improve teachers and students’ awareness of health and safety.

The correlation between air pollutants and outpatient visits in Zhoushan / 预防医学

Objective @#To explore the correlation between air pollution and outpatient visits,and to provide evidence for health risk assessment of air pollutants and intervention. @*Methods @#The data of air pollutants and outpatient visits in 2016 in Zhoushan Hospital were collected,and the outpatient volume on the days when the concentration of air pollutants reached and exceeded the standard were compared. Spearman rank correlation analysis was used to explore the relationship between outpatient volume and the concentration of air pollutants. @*Results @#In 2016,the median（inter-quartile range）of daily outpatient volume in Zhoushan Hospital was 3 304（1 638）person-times. O3,PM2.5 and PM10 were the primary air pollutants in Zhoushan in 2016. The average daily outpatient volume of internal medicine,circulatory system,other diseases and all when the air was polluted at light level or above were higher than those when the air quality was good（P< 0.05）. CO concentration was positively correlated with the average daily outpatient volume of respiratory system and circulatory system（P< 0.05）,was negatively correlated with the average daily outpatient volume of all（P< 0.05）. O3-8 h concentration was positively correlated with the average daily outpatient volume of internal medicine,other diseases and all（P< 0.05）,and was negatively correlated with the average daily outpatient volume of respiratory system and pediatrics（P< 0.05）. SO2 concentration was negatively correlated with the average daily outpatient volume of respiratory system,skin and subcutaneous tissue（P< 0.05）. The concentration of NO2,PM10 and PM2.5 were positively correlated with the average daily outpatient volume of respiratory system and pediatrics（P< 0.05）. @*Conclusion @#The main air pollutants in Zhoushan were O3,PM2.5 and PM10. When they exceed the limits,the outpatient volume would increase.

Microbial contamination of drinking water in rural schools in Shaanxi in 2018 / 中国学校卫生

Objective@#To understand the disinfection status and microbial pollution of water supply project in rural schools in Shaanxi Province in 2018, and to provide basis for improving drinking water quality in rural schools.@*Methods@#Data of water quality of water supply project in rural schools of Shaanxi Province in 2018 was collected, and the disinfectant surplus and microbial index compliance rate were analyzed according to "Sanitary Standard for Drinking Water" (GB 5749-2006).@*Results@#The overall compliance rate of microbial indicators of water supply projects in rural schools in Shaanxi Province was 68.09%, and that of groundwater microbial indicators(71.97%) was higher than that of surface water(61.42%)(χ2=15.68, P<0.01); The overall compliance rate of microbial indicators in flood season(71.85%) was higher than that in dry season(64.34%)(χ2=7.44, P<0.01); The rate of reaching the standard of disinfectant residue was 77.27%. The rate of reaching the standard of microbial index of water samples with disinfection measures was higher than that of water samples without disinfection measures (χ2=31.88, P<0.01), The rate of reaching the standard of microbial index of water samples with disinfectant residue(88.89%) was higher than that of water samples with disinfectant residue(44.44%)(χ2=12.28, P<0. 01).@*Conclusion@#The main cause of microbial contamination of drinking water in rural schools in Shaanxi Province is inadequate equipment of disinfection equipment in water supply projects or not being used as required. It is suggested that schools, education and health departments should take measures to strengthen supervision and management of water plants to ensure the normal use of disinfection equipment.

Effect of moxibustion at "Guanyuan" (CV 4) and "Sanyinjiao" (SP 6) on bone morphology, metabolism and ERα of bone marrow mesenchymal stem cells in the ovariectomized rats / 中国针灸

OBJECTIVE@#To observe the effects of moxibustion at "Guanyuan" (CV 4) and "Sanyinjiao" (SP 6) on bone morphology, metabolism and ERα of bone marrow mesenchymal stem cells (MSCs) in the ovariectomized rats and explore the underlying mechanism of moxibustion at Guanyuan (CV 4) and Sanyinjiao (SP 6) on the regulation of bone metabolism.@*METHODS@#A total of 60 SD rats were randomized into a normal group (20 rats) and an ovariectomy group (40 rats). In the normal group, no any treatment was provided. In the ovariectomy group, the classical ovariectomy was adopted to set up the osteoporosis model. In the 13th week after ovariectomy, 10 rats were collected from each of the normal group and the ovariectomy group for model identification. After model identification, the ovariectomy group was subdivided into a model group, an estradiol group and a moxibustion group, 10 rats in each one. In the normal group and the model group, the gavage was provided with 2 mL 0.9% sodium chloride solution, once a day. In the estradiol group, the gavage was provided with 17β-estradiol 100 μg/(kg•d), once a day. In the moxibustion group, moxibustion was applied at "Guanyuan" (CV 4) and "Sanyinjiao" (SP 6), 15 min at each acupoint, once a day. The 6 treatments were as one course, with 1 day of interval, 12 courses were required. After 12-week intervention, the dual-energy X-ray was adopted to determine the bone mineral density (BMD) and bone mineral content of the whole body in living condition. After sacrificed, HE staining was adopted to observe femur structure, the enzyme-linked immunosorbent assay was to determine the absorbance of estradiol (E) and alkaline phosphatase (ALP) in serum and the real-time quantitative PCR method was to determine the mRNA expressions of ERα of MSCs in tibia and femur.@*RESULTS@#Compared with the model group, BMD was increased obviously in the pelvis and spine in the moxibustion group and the estradiol group (0.05). Compared with the model group, the bone trabeculas were stronger and well connected in the moxibustion group, indicated by HE staining. Compared with the model group, the concentrations of E in serum were increased obviously in the estradiol group and the moxibusiton group (both <0.01), and ALP concentrations reduced obviously in the estradiol group and the moxibustion group (both <0.001), the mRNA expressions of ERα in MSCs increased in the estradiol group and the moxibustion group (both <0.001).@*CONCLUSION@#Moxibustion at "Guanyuan" (CV 4) and "Sanyinjiao" (SP 6) effectively increases BMD and bone strength in the ovariectomized rats and the mechanism may be related to the improvement of serum E concentration, the decrease of serum ALP concentration and the up-regulation of mRNA expression of ERα in MSCs.

Value of Adjuvant Radiotherapy for Thymoma with Myasthenia Gravis after Extended Thymectomy / 中华医学杂志(英文版)

<p><b>Background</b>The co-existence of myasthenia gravis (MG) and thymoma makes the surgical treatment more complicated and adjuvant radiation more controversial. The aim of this study was to investigate adjuvant radiotherapy for thymoma with MG after extended thymectomy.</p><p><b>Methods</b>A total of 181 patients with both MG and thymoma were recruited between 2003 and 2014 at Tongren Hospital, China. Among all the patients, 157 patients received radiation therapy after surgery (Group A); whereas the other 24 patients did not receive radiation therapy (Group B). According to the time that patients started mediastinal radiation therapy, we subdivided the 157 patients in Group A into subgroups (1-month subgroup, n = 98; 2-month subgroup, n = 7; and 3-month subgroup, n = 52). We then compared the effect of the mediastinal radiation therapy across these different groups using the survival rate, the rate of postoperative myasthenic crisis, and the complete stable remission (CSR) rate as the primary endpoints.</p><p><b>Results</b>There was a significant difference in the occurrence of postoperative myasthenic crisis between 1-month subgroup and Group B (χ = 4.631, P = 0.031). The rates of reaching CSR were 32.6% in 1-month subgroup, 25% in 3-month subgroup, and 22.7% in Group B, respectively. The overall survival rates of 1-month subgroup, 3-month subgroup, and Group B were 88.8%, 83.3%, and 77.3%, respectively. Analysis on the Kaplan-Meier survival curves demonstrated that within 8 years after surgery, there was no significant difference in aspects of overall survival and disease-free survival between 1-month subgroup and Group B, and between 3-month subgroup and Group B; over 8 years after surgery, the disease-free survival rates in 1-month subgroup, 3-month subgroup and Group B were 79.4%, 70.6%, and 55.3%, respectively.</p><p><b>Conclusions</b>Adjuvant radiation within 1 month after extended thymectomy may be helpful in controlling postoperative MG, such as decreasing the possibility of postoperative myasthenic crisis, and raising cumulative probabilities of reaching CSR.</p>

Therapeutic Effects and Mechanism of Chinese Medicine Skin Dialysis for Chronic Renal Failure / 广州中医药大学学报

Objective To observe the influence of Chinese medicine skin dialysis on traditional Chinese medicine (TCM) syndrome scores and microinflammation in patients with chronic renal failure(CRF). Methods A total of 180 patients with CRF were divided into groups A, B and C, 60 cases in each group. All of the 3 groups were given conventional treatment, and additionally, group A was given Chinese medicine skin dialysis, and group B was given pure water dialysis. Meanwhile, 60 healthy volunteers served as normal control group (group D), and had no any medication. The course of treatment lasted for one month. Before and after treatment, we examined the scores of TCM syndromes and the levels of 24-hour urinary protein, serum creatinine (SCr), blood urea nitrogen (BUN), estimated glomerular filtration rate (eGFR), albumin (ALB), immunoglobulin A(IgA), immunoglobulin G (IgG) , immunoglobulin M(IgM), interleukin 6 (IL-6) , interleukin 1(IL-1), hyper-sensitive C reactive protein (hs-CRP), and tumor necrosis factor alpha (TNF-α). Results After treatment, the scores of TCM syndromes and the levels of 24-hour urinary protein, SCr, BUN, eGFR, IL-6, IL-1, hs-CRP, and TNF-α in the 3 groups were decreased (P < 0.05 compared with those before treatment), and were markedly lower in group A than those in group B and group C (P<0.05); serum levels of IgA, IgG, IgM and ALB in the 3 groups were increased(P < 0.05 compared with those before treatment), and the levels in group A were significantly higher than those in group B and group C (P < 0.05). However, the levels of observation indexes did not arrive to the levels of group D(P<0.05). Conclusion Chinese medicine skin dialysis is effective on relieving the symptoms of CRF patients and enhancing the therapeutic effect through decreasing inflammatory mediators, inhibiting micro-inflammation and improving nutritional status.

Cellular damage of low-dose combined exposure to mercury, lead and cadmium on hippocampal neurons in rats / 中华预防医学杂志

Objective@#To observe the cellular damage of low-dose combined exposure to Hg, Pb and Cd on hippocampal neurons in rat.@*Methods@#SH-SY5Y cells were randomly divided into 8 groups by 2×2×2 factorial design: control group, Pb exposure group, Hg exposure group, Pb+Hg exposure group, Pb+Cd exposure group, Hg+Cd exposure group and Pb+Cd+Hg exposure group. And the cell viabilities were measured. On this basis, an animal model was established. Twenty eight-week-old SD pregnant rats were randomly divided into four groups by random number table, and five in each group: the control group(distilled water), 1-fold metal mixture exposure group (1×MM, poisoning solution containing mercury chloride 0.15 mg/L, lead acetate trihydrate 25 mg/L, cadmium chloride 7.5 mg/L), 5-fold metal mixture exposure group (5×MM, poisoning solution containing mercury chloride 0.75 mg/L, lead acetate trihydrate 125.00 mg/L, cadmium chloride 37.50 mg/L), 10-fold metal mixture exposure group (10×MM, poisoning solution containing mercury chloride 1.50 mg/L, lead acetate trihydrate 250.00 mg/L, cadmium chloride 75.00 mg/L). Pregnant rats drank water until delivery. Twenty male pups were selected and exposed to these metals through breast milk until weaned. The heavy metals dose of poisoning water was adjusted, and then the weaned rats were exposed to heavy metals via drinking poisoning water until adulthood (postnatal day 83). The blood samples and brain hippocampus samples were collected to observe the ultrastructural changes of hippocampus, and to determine the levels of Hg, Pb and Cd in blood. In addition, apoptosis rate and fluorescence intensity of reactive oxygen species and intracellular free calcium concentration ([Ca2+]i) in hippocampal neurons were measured.@*Results@#Cellular factorial design analysis showed that Hg+Pb+Cd (at no observed adverse effect level, 1.0, 0.5 and 0.1 μmol/L, respectively)had a interaction on cell viability after 48 or 72 hours of combined exposure (P<0.05). The results of ultrastructure showed that mitochondria decreased, ridges and matrixes gradually dissolved in rat hippocampal neurons of 5×MM group; nuclear chromatin aggregated, more ridges and matrixes dissolved and the mitochondria also decreased in rat hippocampal neurons of 10×MM group. The concentration of Hg, Pb and Cd in the blood of 1×MM group, 5×MM group and 10×MM group were higher than those in the control group, and the differences were statistically significant (P<0.001). There was no significant difference in apoptosis rate between the 1×MM group and the control group. The apoptosis rate of 5×MM group and 10×MM group was higher than that in the control group, and the differences were statistically significant (P<0.001). There was no statistically significant difference in the fluorescence intensity of reactive oxygen species in hippocampal neurons of the 1×MM group and the control group. The fluorescence intensity of reactive oxygen species in the 5×MM group and the 10×MM group was higher than that in the control group, the difference was statistically significant (P<0.05). There was no significant difference in the fluorescence intensity of [Ca2+]i between the 1×MM group and the control group. The fluorescence intensity values of [Ca2+]i in the 5×MM group and the 10×MM group were higher than the control group, the differences were statistically significant (P<0.001).@*Conclusion@#Low-level combined exposure to Hg, Pb, and Cd caused synergistic neurotoxic damage, and the process may be related to the changes of neuronal apoptosis, reactive oxide species, and [Ca2+]i levels.

Role of TLR4 on vascular injury induced by lower limb ischemia reperfusion / 中国现代普通外科进展

Objective:To explore the role of TLR4 in the process of lower limb ischemia-reperfusion injury.Methods:Ischemia Reperfusion injury model:in this study,the model of lower limb ischemia-reperfusion was established by rubber band wound method,C57BL / 6J mice were randomly divided into model control group(IR) and ischemia-reperfusion group(IR);TLR4 experiment:The mice models of ischemia reperfusion were divided into wild type (WT) model group and TLR4 knock out (TLR4-/-) model group;The expressions of TLR4 and HMGB1,TNF-α and IL6 were detected by RT-PCR and immunohistochemistry.The apoptosis of vascular wall was detected by TUNEL.Results:The expression of TLR4,HMGB1,TNF-α,IL6 in the IR group was significantly higher than that in the control group (P＜0.01).After TLR4 knockout,the expression of inflammatory factors and apoptosis in IR group was significantly reduced (P＜0.01).Conclusion:TLR4 mediates inflammatory response and induces apoptosis in lower limb ischemia reperfusion injury in mice.

Preparation and characterization of laser microporous acellular osteochondral scaffolds / 中国组织工程研究

BACKGROUND: Preparing a scaffold with cartilage derived components and good initial mechanical strength is the direction of tissue engineering cartilage research. OBJECTIVE: To prepare porous acellular osteochondral scaffolds, and to explore their mechanical properties and cell compatibility. METHODS: Osteochondral bone from the porcine knee joint was taken, and then porous osteochondral scaffolds were made by laser microporation technology. Subsequently, the scaffolds were decellularized chemical methods. Scaffold structure was observed by scanning electron microscopy, and the compression modulus of the scaffolds was determined. Bone marrow mesenchymal stem cells were cultured in L-DMEM containing 10% fetal bovine serum (control group) and cultured in the medium extract of porous acellular osteochondral scaffolds (experimental group), respectively. Cell proliferation was detected by cell counting kit-8 method within 5 days of culture. Bone marrow mesenchymal stem cells were seeded on the porous acellular osteochondral scaffolds, and within 28 days of co-culture, cell growth was observed by hematoxylin-eosin staining and toluidine blue staining. RESULTS AND CONCLUSION: (1) Observation under scanning electron microscopy: The porous acellular osteochondral scaffolds had the smooth surface with evenly distributed pores. The pores of the scaffold extended longitudinally into the subchondral bone. (2) Mechanical properties: The average compressive modulus of porous acellular osteochondral scaffolds was 0.77 MPa, which was close to the compression modulus of the normal cartilage (1.15 MPa). (3) Cell counting kit-8 test: There were no differences in cell proliferation between the control and experimental groups at 1, 2, 3, 4 and 5 days of culture. (4) Cell-scaffold co-culture: A large amount of bone marrow mesenchymal stem cells were observed to be adherent to the scaffold after 1 day of culture through hematoxylin-eosin and toluidine blue staining. However, as time went on, a few cells adhered to the pore wall or grew into the pores at 7 and 21 days of culture. There were also some adherent cells but a large amount of cell masses formed in the pores at 28 days of culture. To conclude, the porous acellular osteochondral scaffold has good mechanical properties and cell compatibility.

Intra-articular migration of transplanted bone marrow mesenchymal stem cells in rats with articular cartilage injury / 中国组织工程研究

BACKGROUND: The application of mesenchymal stem cells (MSCs) in the treatment of cartilage damage has become a hot spot of research. Further studies on the distribution of MSCs in the body after injection and on the underlying mechanism of action are needed. OBJECTIVE: To observe the migration of bone marrow mesenchymal stem cells (BMSCs) after injection into the region of osteochondral defect. METHODS: Thirty Sprague-Dawley rats were randomized into two groups (n=15 per group). In the control group, the femoral tochlear was exposed but an osteochondral defect was not made; and after the suture, PKH26-labeled BMSCs were directly injected into the articular cavity of rats. In the experimental group, a cartilage defect of 1 mm in diameter and 1 mm in depth was made in the rat femoral trochlea, and 5×106PKH26-labeled BMSCs were injected into the defect after operation. At 1, 3 and 7 days after injection, the femoral condyle was taken to make frozen sections followed by DAPI staining. The distribution of BMSCs was observed under laser scanning confocal microscope. RESULTS AND CONCLUSION: In the control group, PKH26-labeled BMSCs were not transferred to the subchondral bone. In the experimental group, BMSCs were detected in the subchondral bone area at 1, 3 days after injection of PKH26-BMSCs in the bone cartilage defect area, and the BMSCs were also found in the bone marrow cavity at 7 days after injection. In conclusion, BMSCs in the articular cavity cannot migrate into the subchondral bone and bone marrow cavity unless the cartilage of the femoral condyle is damaged.

Sensitive Detection of Telomerase Based on Hybridization Chain Reaction-assisted Multiple Signal Amplification / 分析化学

A new electrochemical method for telomerase activity assay was developed on the basis of hybridization chain reaction ( HCR)-assisted multiple signal amplification, aiming at improving the sensitivity and specificity of telomerase assay. The experiments utilized HeLa cells as original source of the telomerase in the electrochemical studies. The telomerase primer was firstly self-assembled on the surface of gold electrode. The telomerase catalyzed the elongation of the primer, producing the complementary sequences of hairpin probe H1. In this case, HCR was then initiated by interacting with two hairpin probes H1 and H2. Because both H1 and H2 were modified by biotin, horseradish peroxidase could be captured on the electrode surface through the high-affinity interaction between biotin and streptavidin, catalyzing the oxidation of o-phenylenediamine to produce 2,3-diaminophenazine. Therefore, the telomerase assay was realized by tracing the electrochemical signals with differential pulse voltammetry. This electrochemical method was of high efficiency and feasibility for detecting telomerase activity, and could trace the telomerase activity down to 10 cells/mL HeLa cells with a wide linear range. Besides, it could also easily distinguish the target enzyme from the control proteins with high specificity.

Clinical Study of Cytomegalovirus Infection and Preemptive Therapy after Allogenic Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To analyze the clinical characteristics of cytomegalovirus(CMV) infection after allogenic hematopoietic stem cell transplantation(allo-HSCT) and the effect of preemptive therapy.</p><p><b>METHODS</b>A total of 134 patients who underwent allo-HSCT from March 2010 to March 2015 in the Department of Hematology of our hospital were enrolled in this study. The CMV infection rate, the median time of CMV infection occurence, and the risk factors for CMV infection after allo-HSCT, the response rate of preemptive treatment and the median time of CMV-DNA turning negative were analyzed. Five-year overall survival rate was compared between the patients with or without CMV infection.</p><p><b>RESULTS</b>The incidence of CMV viremia was 55.2％(74／134), and the median time for the CMV with CMV-DNA positive for the first time was 34 days(14-283) after allo-HSCT．Both univariate and multivariate analysis showed that the thymoglobulin(ATG) used in conditioning regimen and Ⅱ-Ⅳ grade of aGVHD were the risk factors for CMV viremia. After preemptive treatment the 85.1% of patient with CMV viremia turned negative, and the median time of CMV-DNA turning negative were 15 days(5-82), only 2 patients died of CMV pneumonia. Five-year overall survival rate of the patients with or wihout CMV viremia was 49% and 66.3% respectively, and the difference between the 2 groups was significant(P=0.041）.</p><p><b>CONCLUSION</b>The ATG used in conditioning regimen and Ⅱ-Ⅳ grade of aGVHD may increase the incidence of CMV infection after allo-HSCT, and the preemptive thrapy can effectively prevent the CMV viremia turning to CMV disease.</p>

Logistic regression analysis on risk factors of autism spectrum disorders / 中华实用儿科临床杂志

Objective To explore the possible risk factors for autism spectrum disorders (ASD),and to pro-vide a basis for exploring the etiology of the disease.Methods This case -control study included 68 patients diag-nosed as ASD for a first lifetime(according to the fourth edition of the American Diagnostic and Statistical Manual of Mental Disordersfor ASD diagnosis)from May 201 4 to January 201 5,and 77 non -ASD controls (normal children, matched on gender)in Jiangxi Children′s Hospital were selected to undergo the risk factor survey for ASD.The survey content included 1 0 categories:general status,birth,feeding,the past history,mother′s pregnancy and her health condi-tion during pregnancy and environmental exposure,parents′occupational exposure,family history and relevant test re-sults.Logistic regression analysis was performed to analyze the results of the survey.Results The possible risk factors for ASD increased if mother had virus infection 2 years before pregnant (OR =7.97,95%CI:2.42 -26.31 ),had occu-pational exposure (OR =3.99,95%CI:1 .27 -1 2.52),volatile organic compounds exposure during pregnancy (OR =22.21 ,95%CI:2.28 -21 6.09),as well as living closely to transport passage ways during pregnancy (OR =0.59,95%CI:0.38 -0.93)or having a family heredity history (OR =58.50,95%CI:5.81 -589.57).Breastfeeding (OR =0.81 ,95%CI:0.66 -0.98)might be a protective factor in ASD.Conclusions In addition to genetic factors,the ute-rine environment from conception to birth and growth environment play an important role in the pathogenesis of ASD.

Characterization of acid-and pepsin-soluble collagens from spines and skulls of skipjack tuna (Katsuwonus pelamis) / 中国天然药物

Acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from the spine (ASC-SP and PSC-SP) and skull (ASC-SK and PSC-SK) of the skipjack tuna, Katsuwonus pelamis, were successfully isolated and characterized. The yields of ASC-SP, PSC-SP, ASC-SK and PSC-SK were (2.47 ± 0.39)%, (5.62 ± 0.82)%, (3.57 ± 0.40)%, and (6.71 ± 0.81)%, respectively, on the basis of dry weight. The four collagens contained Gly (330.2-339.1 residues/1 000 residues) as the major amino acid, and their imino acid contents were between 168.8 and 178.2 residues/1 000 residues. Amino acid composition, SDS-PAGE, and FTIR investigations confirmed that ASC-SP and ASC-SK were mainly composed of type I collagen, and had higher contents of high-molecular weight cross-links than those of PSC-SK and PSC-SP. The FTIR investigation also certified all the collagens had triple helical structure. The denaturation temperatures of ASC-SK, PSC-SK, ASC-SP, and PSC-SP were 17.8, 16.6, 17.6, and 16.5 °C, respectively. All isolated collagens were soluble at acidic pH (1-5) and lost their solubilities when the NaCl concentration was above 2% (W/V). The isolated collagens from the spines and skulls of skipjack tuna could serve as an alternative source of collagens for further application in food, cosmetic, biomedical, and pharmaceutical industries.