High-frequency repetitive transcranial magnetic stimulation regulates neural oscillations of the hippocampus and prefrontal cortex in mice by modulating endocannabinoid signalling

BACKGROUND

Neural oscillations play a role in the antidepressant effects of repetitive transcranial magnetic stimulation (rTMS). However, the effects of high-frequency rTMS on the neural oscillations of the medial prefrontal cortex (mPFC) and hippocampus (HPC) and its molecular mechanism have not been fully clarified.

METHODS

The depressive-like behaviours, local field potentials (LFPs) of the ventral HPC (vHPC)-mPFC, and alternations of endocannabinoid system (ECS) in the HPC and mPFC were observed after rTMS treatment. Meanwhile, depressive-like behaviours and LFPs were also observed after cannabinoid type-1 receptor (CB1R) antagonist AM281 or monoacylglycerol lipase inhibitor JZL184 injection. Moreover, the antidepressant effect of rTMS was further assessed in glutamatergic-CB1R and gamma-amino butyric acid (GABA)-ergic -CB1R knockout mice.

RESULTS

Alternations of endocannabinoids and energy value and synchronisation of mPFC-vHPC, especially the decrease of theta oscillation induced by CUMS, were alleviated by rTMS. JZL184 has similar effects to rTMS and AM281 blocked the effects of rTMS. GABAergic-CB1R deletion inhibited CUMS-induced depressive-like behaviours whereas Glutaminergic-CB1R deletion dampened the antidepressant effects of rTMS.

LIMITATIONS

The immediate effect of rTMS on field-potential regulation was not observed. Moreover, the role of region-specific regulation of the ECS in the antidepressant effect of rTMS was unclear and the effects of cell-specific CB1R knockout on neuronal oscillations of the mPFC and vHPC should be further investigated.

CONCLUSION

Endocannabinoid system mediated the antidepressant effects and was involved in the regulation of LFP in the vHPC-mPFC of high-frequency rTMS.

The Impact of Electroacupuncture Early Intervention on the Brain Lipidome in a Mouse Model of Post-traumatic Stress Disorder

The neuroprotective effect of electroacupuncture (EA) treatment has been well studied; growing evidence suggests that changes in lipid composition may be involved in the pathogenesis of post-traumatic stress disorder (PTSD) and may be a target for treatment. However, the influence of early EA intervention on brain lipid composition in patients with PTSD has never been investigated. Using a modified single prolonged stress (mSPS) model in mice, we assessed the anti-PTSD-like effects of early intervention using EA and evaluated changes in lipid composition in the hippocampus and prefrontal cortex (PFC) using a mass spectrometry-based lipidomic approach. mSPS induced changes in lipid composition in the hippocampus, notably in the content of sphingolipids, glycerolipids, and fatty acyls. These lipid changes were more robust than those observed in the PFC. Early intervention with EA after mSPS ameliorated PTSD-like behaviors and partly normalized mSPS-induced lipid changes, notably in the hippocampus. Cumulatively, our data suggest that EA may reverse mSPS-induced PTSD-like behaviors due to region-specific regulation of the brain lipidome, providing new insights into the therapeutic mechanism of EA.

Alterations of Plasma Lipids in Adult Women With Major Depressive Disorder and Bipolar Depression

Lipidomics has been established as a potential tool for the investigation of mental diseases. However, the composition analysis and the comparison of the peripheral lipids regarding adult women with major depressive depression (MDD) or bipolar depression (BPD) has been poorly addressed. In the present study, age-matched female individuals with MDD (n = 28), BPD (n = 22) and healthy controls (HC, n = 25) were enrolled. Clinical symptoms were assessed and the plasma samples were analyzed by comprehensive lipid profiling based on liquid chromatography-mass spectrometry (LC/MS). We found that the composition of lipids was remarkably changed in the patients with MDD and BPD when compared to HC or compared to each other. Moreover, we identified diagnostic potential biomarkers comprising 20 lipids that can distinguish MDD from HC (area under the curve, AUC = 0.897) and 8 lipids that can distinguish BPD from HC (AUC = 0.784), as well as 13 lipids were identified to distinguish MDD from BPD with moderate reliability (AUC = 0.860). This study provides further understanding of abnormal lipid metabolism in adult women with MDD and BPD and may develop lipid classifiers able to effectively discriminate MDD from BPD and HC.

[Current status and challenges for taeniasis and cysticercosis control in China]

In the WHO new road map for neglected tropical diseases 2021-2030, the disease-specific targets are classified into control, elimination as a public health problem, elimination and eradication, and taeniasis and cysticercosis are targeted for control. The overall prevalence of taeniasis and cysticercosis is low in China, and varies remarkably in regions and populations; however, there are many challenges for elimination of taeniasis and cysticercosis in China. Based on previous taeniasis and cysticercosis control programs, developing a sensitive taeniasis and cysticercosis surveillance-response system, updating criteria for diagnosis of taeniasis and cysticercosis, proposing a national guideline for treatment of taeniasis and cysticercosis, and strengthening interdisciplinary and intersectoral communications and collaborations are urgently needed under the One Health concept.

[Prevalence of soil - borne nematode infections among residents living in urban/town areas of China in 2015]

OBJECTIVE

To understand the prevalence of soil-borne nematode infections among residents living in urban/town areas of China, so as to provide insights into the control and elimination of soil-borne nematodiasis.

METHODS

A total of 5 epidemic areas were classified in China according to the prevalence of human Clonorchis sinensis infections captured from the 2014-2015 national survey on major human parasitic diseases in China, and the total sample size was estimated according to the binomial distribution and Poisson's distribution. Then, the total sample size was allocated proportionally to each province (autonomous region, municipality) of China based on the percentage of residents living in urban and town areas, and the number of survey sites in each province (autonomous region, municipality) was proportionally assigned according to the percentages of residents living in urban and town areas. Then, stratified sampling was performed at county, township and community levels according to the number of sampling sites in each province (autonomous region, municipality), and the survey site (community) was defined as the smallest sampling unit. All permanent residents in the survey sites were selected as the study subjects, and their stool samples were collected for identification and counting of parasite egg using a Kato-Katz technique. The prevalence and intensity of each parasite species were calculated.

RESULTS

From 2014 to 2015, among the 133 231 residents detected in 31 provinces (autonomous regions, municipalities) of China, the overall prevalence of soil-borne nematode infections was 1.23% (1 636/133 231), and the prevalence rates of hookworm, Ascaris lumbricoides and Trichuris trichiura infections were 0.77% (1 032/133 231), 0.32% (426/133 231) and 0.17% (224/133 231), respectively. The highest prevalence of soil-borne nematode infections was seen in Jiangxi (4.03%, 82/2 034) and Chongqing (4.03%, 524/13 012), followed by in Hainan (3.47%, 72/2 075). The prevalence of soilborne nematode infections was 1.07% (662/62 139) in men and 1.37% (974/71 092) in women, and the greatest prevalence was found in residents at ages of 65 to 70 years (2.56%, 219/8 569). With regard to occupations and education levels, herdsmen (2.47%, 2/81) and illiterate residents (3.33%, 226/6 795) were found to have the highest prevalence of soil-borne nematode infections, respectively. In addition, mild infections were predominantly identified in hookworm-, A. lumbricoides- and T. trichiura-infected individuals (all > 90%).

CONCLUSIONS

The overall prevalence of soil-borne nematodiasis remains low in urban and town areas of China; however, human infections are widespread. According to the epidemiological features, health education combined with deworming are recommended to reduce the prevalence of soil-borne nematode infections among residents living in urban and town areas of China.

The impact of quetiapine on the brain lipidome in a cuprizone-induced mouse model of schizophrenia

The antipsychotic effect of Quetiapine (Que) has been extensively studied and growing evidence suggests that Que has a beneficial effect, improving cognitive functions and promoting myelin repair. However, the effects of Que on the brain lipidome and the association between Que-associated cognitive improvement and changes in lipids remain elusive. In the present study, we assessed the cognitive protective effects of Que treatment and used a mass spectrometry-based lipidomic approach to evaluated changes in lipid composition in the hippocampus, prefrontal cortex (PFC), and striatum in a mouse model of cuprizone (CPZ)-induced demyelination. CPZ induces cognitive impairment and remarkable lipid changes in the brain, specifically in lipid species of glycerophospholipids and sphingolipids. Moreover, the changes in lipid classes of the PFC were more extensive than those observed in the hippocampus and striatum. Notably, Que treatment ameliorated cuprizone-induced cognitive impairment and partly normalized CPZ-induced lipid changes. Taken together, our data suggest that Que may rescue cognitive behavioral changes from CPZ-induced demyelination through modulation of the brain lipidome, providing new insights into the pharmacological mechanism of Que for schizophrenia.

The impact of repetitive transcranial magnetic stimulation and fluoxetine on the brain lipidome in a rat model of chronic unpredictable stress

The antidepressant effect of repetitive transcranial magnetic stimulation (rTMS) has been extensively studied; growing evidence suggests that changes in lipid composition may be involved in the pathogenesis of depression and may be a targeted mechanism for treatment. However, the influence of rTMS on lipid composition and the differences between these effects compared to antidepressants like fluoxetine (Flx) have never been investigated. Using a chronic unpredictable stress (CUS) model in rats, we assessed the antidepressive effects of rTMS and Flx treatments and evaluated changes in lipid composition in the hippocampus and prefrontal cortex (PFC) using a mass spectrometry-based lipidomic approach. Both rTMS and Flx treatments ameliorated depressive-like behaviors induced by CUS. Moreover, changes in lipid composition, especially glycerophospholipids, sphingolipids, and glycerolipids induced by CUS in the hippocampus were more robust than those observed in the PFC. CUS led to decreased levels of 20 carbon-containing fatty acyls and polyunsaturated fatty acyls in the PFC, and decreased levels of acyl carnitines (AcCa) in both the hippocampus and PFC. Notably, rTMS treatment had higher impact than Flx on composition of glycerophospholipids and sphingolipids in the hippocampus that were altered by CUS, while Flx attenuated CUS-induced changes in the PFC to a greater extent than rTMS. However, neither was able to restore fatty acyls and AcCa to baseline levels. Altogether, modulation of the brain lipidome may be involved in the antidepressant action of rTMS and Flx, and the degree to which these treatments induce changes in lipid composition within the hippocampus and PFC might explain their differential antidepressant effects.

A double-blind, randomized, sham-controlled study of cranial electrotherapy stimulation as an add-on treatment for tic disorders in children and adolescents

AIM

The aim of this study was to determine the efficacy and safety of cranial electrotherapy stimulation (CES) as an add-on treatment for TD.

METHODS

A randomized, double-blind, sham-controlled trial was conducted at an outpatient, single-center academic setting. A total of 62 patients aged 6-17 years with TD and lack of clinical response to 4 weeks' pharmacotherapy were enrolled. Patients were divided randomly into 2 groups and given 4 weeks' treatment, including 30 min sessions of active CES (500 μA-2 mA) or sham CES (lower than 100 μA) per day for 40 d on weekdays. Change in Yale Global Tic Severity Scale (YGTSS), Clinical Global Impression-severity of illness-severity (CGI-S) and Hamilton Anxiety Scale-14 items (HAMA-14) were performed at baseline, week 2, week 4. Adverse events (AEs) were also evaluated.

RESULTS

53 patients (34 males and 9 females) completed the trial, including 29 in the active CES group and 24 in the sham CES group. Both groups showed clinical improvement in tic severities compared to baseline respectively at week 4. Participants receiving active CES showed a reduction of 31.66 % in YGTSS score, compared with 23.96 % in participants in sham CES group, resulting in no significant difference between the two groups (t = 1.54, p = 0.13).

CONCLUSION

Four-week's treatment of CES for children and adolescents with TD is effective and safe, but the improvement for tic severity may be related to placebo effect.

[National surveillance on Enterobius vermicularis infections among children at ages of 3 to 9 years in China from 2016 to 2018]

OBJECTIVE

To understand the epidemic status of Enterobius vermicularis infections among children aged 3 to 9 years in China, so as to provide scientific basis for the formulation of the prevention and control strategies for enterobiasis.

METHODS

The national surveillance of enterobiasis was performed in 736 national surveillance sites (counties) from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018. All surveillance sites were classified into parts according to the geographical directions, including the eastern, western, southern, northern and middle parts, and a township was randomly selected from each part. Then, an administrative village was randomly selected from the township, and 200 permanent residents at ages of over 3 years living in the administrative village were randomly selected using the cluster sampling method. A total of 1 000 residents were examined in each surveillance site. E. vermicularis infections were detected among children at ages of 3 to 9 years using the modified Kato-Katz technique and the adhesive cellophane-tape perianal swab method, and the prevalence of infections was calculated and compared.

RESULTS

The prevalence of E. vermicularis infections was 2.50%, 2.84% and 2.46% among children at ages of 3 to 9 years in the 736 surveillance sites from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018, and there was no gender-specific prevalence of E. vermicularis infections (P > 0.05). Enterobiasis was main prevalent in the southern and southwestern part of China (Jiangxi, Guangxi, Guangdong, Sichuan, Fujian, Chongqing and Hainan), with 5.00% prevalence and greater, and the highest prevalence was seen in Jiangxi and Guangxi for successive 3 years. In addition, the prevalence of E. vermicularis infections was higher in children with the Han ethnicity than in those with the minority ethnicity, and a high prevalence was found in children at ages of 4 to 7 years, and a low prevalence seen in children at ages of 3, 8 and 9 years.

CONCLUSIONS

The prevalences of E. vermicularis infections have not changed much among children at ages of 3 to 9 years in China from 2016 to 2018, and high prevalence is seen in southern and southwestern China, which should be given a high priority.

[Establishment of an evaluation system for the field assessment of the Kato-Katz technique in detection of soil-transmitted nematodiasis]

OBJECTIVE

To establish an evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes, so as to provide insights into the field application of the Kato-Katz technique.

METHODS

The initial evaluation indicators were determined through literature search, brainstorming and expert consultation. The evaluation indicatorswere improved and the weight of each indicator was decided through three rounds of expert consultation by using the Delphimethod. In addition, the expert authority coefficient and the coordination coefficient of each indicator were calculated at eachround of expert consultations.

RESULTS

The recovery rates of the questionnaire were 100.00%, 100.00% and 89.29% at the firstto the third round of the expert consultations, respectively, and the expert authority coefficients were all more than 0.85 at eachround. The final evaluation system included 4 first-level indicators and 15 second-level indicators. In the first-level indicators, "detecting effect" and "funds investment" had the mean weighted value of 4.53 and 4.49, which were relatively higher than that of"person-time investment" and "operability" (both 4.34). Among the second-level indicators under each first-level indicator, thefour most significant indicators included "ability of personnel in egg discrimination", "cooperation of village cadres and doctors","Person-time on testing" and "organizational start-up cost", with the mean weighted values of 4.74, 4.43, 4.39 and 4.17, respectively. The coordination coefficients were 0.39 to 0.65, 0.28 to 0.58 and 0.45 to 0.65 at the first to the third round of the expertconsultations, respectively, and there were significant differences in the coordination coefficients at all three rounds of the consultations (all P < 0.05).

CONCLUSIONS

An evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes is successfully established, among which "ability of personnel in egg discrimination" and "cooperation ofvillage cadres and doctors" have the greatest mean weighted values of the significance.

Repetitive high-frequency transcranial magnetic stimulation reverses depressive-like behaviors and protein expression at hippocampal synapses in chronic unpredictable stress-treated rats by enhancing endocannabinoid signaling

The anti-depressant effect of repetitive transcranial magnetic stimulation (rTMS), a clinically-useful treatment for depression, is associated with changes to the endocannabinoid system (ECS). However, it is currently unknown whether different frequencies of rTMS alter the ECS differently. To test this, rats exposed to chronic unpredictable stress (CUS) were treated with rTMS at two different frequencies (5 (high) or 1 Hz (low), 1.26 Tesla) for 7 consecutive days. Twenty-four hours after the final rTMS treatment, we evaluated depressive-like behaviors and the expression of several synaptic proteins and ECS-related proteins in the hippocampus. In addition, we knocked-down diacylglycerol lipase alpha (DAGLα) and cannabinoid type 1 receptor (CB1R), two important components of the ECS, and measured depressive-like behaviors and synaptic protein expression following rTMS. Furthermore, we measured the expression levels of several components of the ECS system in hippocampal-derived astrocytes and neurons exposed to repetitive magnetic stimulation (rMS) with different parameters (5 or 1 Hz, 0.84 or 1.26 Tesla). Interestingly, we found that only high-frequency rTMS ameliorated depressive-like behaviors and normalized the expression of hippocampal synaptic proteins in CUS-treated rats; this effect was eliminated by knockdown of DAGLα or CB1R. Moreover, we found that rMS at 5 Hz increased the expression of DAGLα and CB1R in hippocampal astrocytes and neurons. Collectively, our results suggest that high-frequency rTMS exerts its anti-depressant effect by up-regulating DAGLα and CB1R.

Early intervention with electroacupuncture prevents PTSD-like behaviors in rats through enhancing hippocampal endocannabinoid signaling

Electroacupuncture (EA) is a clinically useful physiological therapy that has been recently adopted to treat several brain disorders. However, the potential role of early EA intervention in the prevention of posttraumatic stress disorder (PTSD) as well as its potential cellular and molecular mechanism has never been investigated previously. In the present study, we used an enhanced single prolonged stress (ESPS) model to access the effects of early EA intervention on the prevention of anxiety-like and fear learning behaviors, as well as the influence of the expression of post-synaptic density protein 95 (PSD95), synaptophysin (Syn), brain derived neurotrophic factor (BDNF), diacylglycerol lipase alpha (DAGLα) and cannabinoid type 1 receptor (CB1R) in the hippocampus with or without DAGLα or CB1R knockdown by a short hairpin RNA (shRNA) in the hippocampus. Moreover, the effects of electrical stimulation with different parameters on the expression of DAGLα and CB1R in the hippocampal astrocytes were also observed. The results showed that Early EA intervention improved hippocampal synaptic plasticity and ameliorated PTSD-like behaviors and also increased expression of BDNF, DAGLα and CB1R. However, either DAGLα or CB1R knockdown by a short hairpin RNA (shRNA) eliminated the neuroprotective effects of early EA intervention. Furthermore, electrical stimulation with 2/15 Hz 1 mA elevated the expression of DAGLα and CB1R. Altogether, our findings provide new insights regarding the possibility of using early EA intervention in the prevention of PTSD, and the protective effects of EA is involving the activation of DAGLα and CB1R.

Electroacupuncture Pretreatment Ameliorates PTSD-Like Behaviors in Rats by Enhancing Hippocampal Neurogenesis via the Keap1/Nrf2 Antioxidant Signaling Pathway

Electroacupuncture (EA) pretreatment is a clinically useful therapy for several brain disorders. However, whether and via which exact molecular mechanisms it ameliorates post-traumatic stress disorder (PTSD) remains unclear. In the present study, rats received EA stimulation for seven consecutive days before exposure to enhanced single prolonged stress (ESPS). Anxiety-like and fear learning behaviors; hippocampal neurogenesis; the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), Kelch-like ECH-associated protein 1 (keap1), and heme oxygenase 1 (HO-1); and the activity of AMP-activated kinase (AMPK) were evaluated at 14 days after ESPS. EA pretreatment improved hippocampal neurogenesis and ameliorated anxiety-like behaviors in ESPS-treated rats. EA pretreatment also increased the expression of Nrf2 and HO-1 and the activity of AMPK. Furthermore, Nrf2 knockdown by a short hairpin RNA affected anxiety-like behaviors and expression of neuroprotective markers (BDNF, DCX) in a manner similar to ESPS alone and dampened the neuroprotective effects of EA pretreatment. In contrast, Keap1 knockdown increased the expression of HO-1, improved hippocampal neurogenesis, and alleviated PTSD-like behaviors. Altogether, our results suggest that EA pretreatment ameliorates ESPS-induced anxiety-like behaviors and prevents hippocampal neurogenesis disruption in a rat model of PTSD possibly through regulation of the keap1/Nrf2 antioxidant defense pathway.

[Establishment and role of national clonorchiasis surveillance system in China]

Clonorchiasis is one key food-borne parasitic disease in China. Owing to several years'efforts and preparation, the national clonorchiasis surveillance system in China has been established preliminarily since 2016. In this article, the necessity to establish the national clonorchiasis surveillance system is explained. Then, the structure, content and corresponding methods of the surveillance system are briefly introduced. Key points in the surveillance are summarized and the development of surveillance in future is discussed. Furthermore, the contribution of clonorchiasis surveillance in China to the world is also analyzed.

Risperidone ameliorates cognitive deficits, promotes hippocampal proliferation, and enhances Notch signaling in a murine model of schizophrenia

Antipsychotic agents have been reported to promote hippocampal neurogenesis and improve cognitive deficits; yet, the molecular mechanisms underlying these actions remain unclear. In the present study, we used a murine model of schizophrenia induced by 5-day intraperitoneal injection with the non-competitive N-methyl-d-aspartate receptor antagonist MK801 (0.3mg/kg/day) to assess cognitive behavioral deficits, changes in Notch signaling, and cellular proliferation in the hippocampus of adult male C57BL/6 mice after 2-week administration of risperidone (Rip, 0.2mg/kg/day) or vehicle. We then utilized in vivo stereotaxic injections of a lentivirus expressing a short hairpin RNA (shRNA) for Notch1 into the dentate gyrus to examine the role of Notch1 in the observed actions of Rip. We found that Rip ameliorated cognitive deficits and restored cell proliferation in MK801-treated mice in a manner associated with the up-regulation of Notch signaling molecules, including Notch1, Hes1, and Hes5. Moreover, these effects were abolished by pretreatment with Notch1 shRNA. Our results suggest that the ability of Rip to improve cognitive function in schizophrenia is mediated in part by Notch signaling.

Anti-aging pharmacology in cutaneous wound healing: effects of metformin, resveratrol, and rapamycin by local application

Cutaneous wounds are among the most common soft tissue injuries and are particularly hard to heal in aging. Caloric restriction (CR) is well documented to extend longevity; pharmacologically, profound rejuvenative effects of CR mimetics have been uncovered, especially metformin (MET), resveratrol (RSV), and rapamycin (RAPA). However, locally applied impacts and functional differences of these agents on wound healing remain to be established. Here, we discovered that chronic topical administration of MET and RSV, but not RAPA, accelerated wound healing with improved epidermis, hair follicles, and collagen deposition in young rodents, and MET exerted more profound effects. Furthermore, locally applied MET and RSV improved vascularization of the wound beds, which were attributed to stimulation of adenosine monophosphate-activated protein kinase (AMPK) pathway, the key mediator of wound healing. Notably, in aged skin, AMPK pathway was inhibited, correlated with impaired vasculature and reduced healing ability. As therapeutic approaches, local treatments of MET and RSV prevented age-related AMPK suppression and angiogenic inhibition in wound beds. Moreover, in aged rats, rejuvenative effects of topically applied MET and RSV on cell viability of wound beds were confirmed, of which MET showed more prominent anti-aging effects. We further verified that only MET promoted wound healing and cutaneous integrity in aged skin. These findings clarified differential effects of CR-based anti-aging pharmacology in wound healing, identified critical angiogenic and rejuvenative mechanisms through AMPK pathway in both young and aged skin, and unraveled chronic local application of MET as the optimal and promising regenerative agent in treating cutaneous wound defects.

Isoflurane exposure regulates the cell viability and BDNF expression of astrocytes via upregulation of TREK‑1

Neonatal isoflurane exposure in rodents disrupts hippocampal cognitive functions, including learning and memory, and astrocytes may have an important role in this process. However, the molecular mechanisms underlying this disruption are not fully understood. The present study investigated the role of TWIK-related K⁺ channel (TREK-1) in isoflurane-induced cognitive impairment. Lentiviruses were used to overexpress or knockdown TREK-1 in astrocytes exposed to increasing concentrations of isoflurane or O₂ for 2 h. Subsequently, the mRNA and protein expression of brain-derived neurotrophic factor (BDNF), caspase-3, Bcl-2-associated X (Bax) and TREK-1 was measured by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. In addition, cell viability was assessed by a 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium monosodium salt assay. The results demonstrated that, prior to manipulating TREK-1, isoflurane significantly decreased the cell viability and BDNF expression, and increased Bax, caspase-3 and TREK-1 expression was observed. However, TREK-1 overexpression in astrocytes significantly downregulated BDNF expression, and upregulated Bax and caspase-3 expression. Furthermore, lentiviral-mediated short hairpin RNA knockdown of TREK-1 effectively inhibited the isoflurane-induced changes in BDNF, Bax and caspase-3 expression. Taken together, the results of the present study indicate that isoflurane-induced cell damage in astrocytes may be associated with TREK-1-mediated inhibition of BDNF and provide a reference for the safe use of isoflurane anesthesia in infants and children.

WITHDRAWN: Expression analysis of Sca-1 and its significance in lung cancers

Ahead of Print article withdrawn by publisher. The purpose of the present study was to determine the expression of Sca-1, the stem cell marker, among various lung cancers and evaluate their utility. Immunohistochemistry was done in 151 surgically resected lung cancer specimens or biopsies, including 76 cases of adenocarcinoma, 50 cases of squamous cell carcinoma, 15 cases of small cell carcinoma, 6 cases of adenosquamous cell carcinoma and 4 cases of large cell carcinoma. The results showed that 88 (58.3%) cases were Sca-1 positive. Further analysis showed that in cases of adenocarcinoma, the rate of lymph node invasion and poor differentiation level of Sca-1(+) specimens were respectively higher than those of Sca-1(-) specimens. In cases with small cell carcinoma and squamous cell carcinoma, the rates of lymph node invasion of Sca-1(+) specimens were respectively higher than those of Sca-1(-) specimens. Survival analysis showed that for patients with adenocarcinoma and small cell carcinoma, the average survival time of Sca-1(+) patients was significantly shorter than that of Sca-1(-) patients. Further mutation analysis showed that EGFR mutation rates in Sca-1 (-) adenocarcinoma patients were significantly higher than those of Sca-1 (+) patients, while p53 and KRAS mutation rates in Sca-1 (-) adenocarcinoma and squamous cell carcinoma patients were respectively lower than those of Sca-1 (+) patients. Western blots analysis showed that expression of a Src family tyrosine kinase, Fyn, was positively related with Sca-1 expression levels. These results suggested that Sca-1 expression in some human lung cancers was related with malignancy phenotype and survival time. Keywords: Sca-1 expression, stem cancer cell, lung cancer, malignancy phenotype.

Human lung cancer cell line SPC-A1 contains cells with characteristics of cancer stem cells

Cancer stem cells (CSCs) play important roles in occurrence, development, recurrence and metastasis of cancer. Isolation and identification of CSCs have been performed from some cancer tissues or cells. In this paper, human lung adenocarcinoma stem cells were induced and isolated from SPC-A1 cells and their characteristics were determined. SPC-A1 cells were cultured in serum-free medium and epidermal growth factor and basic fibroblast growth factor were added into the medium to induce the formation of multicellular tumor spheroids. The results showed that floating multicellular tumor spheroids (named pulmospheres) were formed 5-10 d after the induction of SPC-A1 cells. Real-time PCR analysis showed that in the pulmospheres, the marker of bronchioalveolar stem cells, Clara cell secretary protein and the marker of AT2 cells, alveolar surfactant protein C were highly expressed. Furthermore, such embryonic stem cell markers as octamer-binding transcription factor 4 (OCT-4), Bmi-1, and thyroid transcription factor -1 (TTF-1) were also highly expressed. Some miRNAs as hsa-miR-126, hsa-miR-145, hsa-let-7g, hsa-let-7d, hsa-let-7c, hsa-let-7e and hsa-miR-98, which were lowly expressed in SPC-A1 cells, were not expressed in the pulmospheres. Cell cycle analysis showed that 94.29 % of the pulmosphere cells were in G1 stages. Further study showed that these cells possessed higher proliferation and invasion activity than SPC-A1 cells. Tumorigenicity activity experiments on BALB/c nude mice showed that 1 × 103 of the pulmosphere cells could form tumors with similar pathological features with lung adenocarcinoma. In conclusion, lung adenocarcinoma stem cells were enriched in the pulmosphere cells and were with high tumorigenicity.

A methodology of characterizing status and trend of land changes in oases: a case study of Sangong River watershed, Xinjiang, China

Land change is often studied with Markov models to develop a probability transition matrix. The existing methods dependent on such matrixes cannot effectively characterize some important aspects associated with land change such as status, direction, trend and regional variations. This study presents mathematical models to quantify these elements, defining unbalanced, quasi-balanced and balanced status, one- and two-way transitions and the rising or falling trends. Using these models and remote-sensing imageries, the landscape was studied for a case area, the oasis of Sangong River in Xinjiang, Northwest China where typical arid conditions prevail. Land expansion and contraction among various land types and for the entire oasis were analyzed for the periods of 1978-1987, 1978-1998 and 1987-1998. The changes were closely related to a strong economic growth after the land-reform campaign and adoption of the market economy in China in the 1980s to early 1990s, a process not strictly Markovian that requires stationarity and randomness. Information on land-change status and trend is important for a better understanding of the underlying driving processes but also for land-use planning and decision-making.

[On cleanliness of hands in diminution of Ascaris lumbricoides infection in children]

OBJECTIVE

To study the relationship between cleanliness of children's hands and diminution of Ascaris lumbricoides infection.

METHODS

Before the study all persons positive for ascaris eggs in the preliminary survey were treated with albendazole. Hand-washing habit before meal and after defecation was kept in children of experimental group, but not in the control group. Kato thick smear stool examination was done once every two months for one year to compare the new infection rates in children without ascaris infection in the two groups, and the reinfection rates in the cured negative cases were also compared between them in half a month after chemotherapy.

RESULTS

All the new infection rates as well as reinfection rates of each reexamination in the experimental group were significantly lower than that of the control group (P < 0.001). Reexamination one year later showed that the ascaris infection rate of the experimental group was 35.2%, reducing by 48.5% as compared with 68.3% before the operation of the project; while ascaris infection rate of the control group was 73.7%, increasing by 78.0% as compared with 41.4% before the operation of the project.

CONCLUSION

Washing hands with toilet soap to keep hands clean can significantly reduce ascaris infection rate.

Development of a K562 cell-based assay for screening anticancer agents

AIM

To develop a leukemia cell line K562-based assay for high-throughput screening.

METHODS

The screening was carried out on 96-well plates with monitoring cell proliferation by a combined 3-[4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium (MTS)/phenazine methosulfate (PMS) method. Conditions for evaluating effects on the proliferation of K562 cells by individual compounds on the 96-well plates were optimized.

RESULTS

A set of 800 small organic compounds was screened for anticancer activity by this cell-based assay, with consumption of each compound at 500 ng. Eleven compounds were identified with >80 % inhibitory activity at 5 mg/L, among which 9 compounds were confirmed by subsequent testing at multiple concentrations. The most potent compound showed an IC50 at 170 nmol/L, and there were total of 7 compounds showed IC50 less than 10 micromol/L.

CONCLUSION

The high-throughput method using K562 cell line is fast, economical, effective, and practical in identifying inhibitors as potential therapeutic agents for cancer.