Effect of electroacupuncture on neuronal programmed necrosis by regulating RIP1/RIP3/MLKL pathway in rats with cerebral ischemia reperfusion injury

OBJECTIVES

To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi"(LI11) and "Zusanli"(ST36) in the rats with cerebral ischemia reperfusion injury and its influence on programmed necrosis of cerebral cortical neurons.

METHODS

Sixty male SD rats were randomly divided into sham-operation group, model group, EA group and inhibitor group, with 15 rats in each group. Left middle cerebral artery occlusion model was established using the modified thread embolism method. In the sham-operation group, the carotid artery was exposed and dissociated in each rat. EA was applied to "Quchi"(LI11) and "Zusanli"(ST36) on the right side for 30 min each time, once daily for 7 days in the rats of the EA group. The rats in the inhibitor group were intraperitoneally injected with norstatin-1 (0.6 mg/kg) for consecutive 7 days. The neurological deficit score of rats in each group was observed. HE staining was adopted to detect the degree of pathological damage of the cerebral cortex in the infarction area. Using TUNEL staining, the apoptosis of cortical neurons in the infarction area was determined；the contents of tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 were detected by ELISA；the mRNA and protein expression of the receptor interacting protein-1 (RIP1), the receptor interacting protein-3 (RIP3) and the substrate mixed lineage kinase like protein (MLKL) were detected by fluorescence quantitative PCR and Western blot, respectively.

RESULTS

In comparison with the sham-operation group, the neurological deficit score in the model group was higher(P<0.01)；HE staining showed that there was the pathological damage in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1β and IL-6, and the mRNA and protein expressions of RIP1, RIP3 and MLKL increased(P<0.01) in the model group. In the EA group, the neurological deficit score was reduced(P<0.01)；HE staining showed that the pathological damage was ameliorated in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1β and IL-6, and the mRNA and protein expressions of RIP1, RIP3, MLKL decreased(P<0.05, P<0.01) when compared with those in the model group.

CONCLUSIONS

EA can attenuate cerebral ischemia reperfusion injury and display its neuroprotective effect probably through inhibiting programmed necrosis of cerebral cortical neurons in the rats.

[Clinical characteristics and prognostic factors of breast cancer patients with tumor deposits in the ipsilateral axillary region]

Objective: To investigate the clinicopathologic features and prognostic factors of breast cancer patients with tumor deposits in the ipsilateral axillary region. Methods: We retrospectively analyzed the clinicopathologic data and follow-up results of 155 patients with breast cancer diagnosed for the first time and complicated with tumor deposits in the ipsilateral axillary region in the Department of Thyroid-Breast-Vascular Surgery of Xijing Hospital from January 2008 to September 2018. Kaplan-Meier method was used for survival analysis. Log rank test was used for the univariate analysis of prognostic factors, and Cox regression was used for multivariate analysis. Results: The median disease free survival (DFS), median distant metastasis free survival (DMFS), and median overall survival (OS) of the 155 patients were 52.0 months, 66.6 months, and 102.2 months, respectively. The 5-year and 10-year DFS rates were 45.7% and 23.1%, the 5-year and 10-year DMFS rates were 56.9% and 28.9%, and the 5-year and 10-year OS rates were 79.3% and 46.0%, respectively. Multivariate Cox regression analysis showed that family tumor history (HR=0.362, 95% CI: 0.140-0.937), clinical T stage (T3: HR=3.508, 95% CI: 1.380-8.918; T4: HR=2.220, 95% CI: 1.076-4.580), estrogen/progesterone receptor status (HR=0.476, 95% CI: 0.261-0.866), number of tumor deposits (HR=1.965, 95% CI:1.104-3.500) and neoadjuvant chemotherapy (HR=1.961, 95% CI: 1.032-3.725) were independent influencing factors for DFS. Molecular subtype [human epidermal growth factor receptor-2(HER-2) positive and hormone receptor negative: HR=7.862, 95% CI: 3.189-19.379], number of tumor deposits (HR=2.155, 95% CI: 1.103-4.212), neoadjuvant chemotherapy (HR=5.002, 95% CI: 2.300-10.880) and radiotherapy (HR=2.316, 95% CI: 1.005-5.341) were independent influencing factors of DMFS. Histological grade (HR=4.362, 95% CI: 1.932-9.849), estrogen/progesterone receptor expression (HR=0.399, 95% CI: 0.168-0.945), HER-2 expression (HR=2.535, 95% CI: 1.114-5.768) and neoadjuvant chemotherapy (HR=4.080, 95% CI: 1.679-9.913) were independent influencing factors of OS. Conclusions: The presence of tumor deposits weakens the influence of axillary lymph node status and distant metastases on the prognosis of breast cancer patients. Therefore, a clinicopathological staging system taking into account tumor deposits should be developed. Since the number of tumor deposits affects the risk of recurrence and metastasis of breast cancer patients, we recommend that the number of tumor deposits should be reported in detail in the pathological report after breast cancer surgery.

Effect of Yiyuan moxibustion on urodynamics and TRPV4/ATP/P2X5 signal pathway of bladder tissue in rats with neurogenic bladder after sacral cord injury

OBJECTIVES

To observe the effect of Yiyuan moxibustion on urodynamics and the expressions of transient receptor potential vanilloid 4 (TRPV4), adenosine triphosphate (ATP), tyrosine protein kinase KIT (C-Kit) and adenosine triphosphate receptor P2X5 in bladder tissue of rats with detrusor reflex-free neurogenic bladder (NB) after sacral cord injury (SCI), so as to explore its mechanism in promoting the recovery of urination function of NB rats.

METHODS

Female SD rats were randomly divided into sham operation, model, Yiyuan moxibustion, Yiyuan moxibustion+inhibitor (combination) and inhibitor groups, with 12 rats in each group. The model of detruser reflex-free NB after sacral SCI was established by modified Hassan Shaker spinal cord transection method. The behavioral score of Basso Beasttie Bresnahan (BBB) and urodynamic indexes were used to evaluate the model of rats after operation. Fifteen days after modeling, Yiyuan moxibustion was applied to "Shenque" (CV8) and "Guanyuan" (CV4) for 20 min, once daily for 14 days. Rats of the inhibitor and combination groups were given intravesical instillation of HC067047 (1 mL, 1 μmol/L, 30 min). After the interventions, urodynamics was used to evaluate the bladder function of rats. HE staining was used to observe the morphology of bladder tissue. ATP content in bladder tissue was detected by colorimetric method. The positive expression rates of C-Kit and their receptor P2X5 in bladder tissue were observed by immunofluorescence double labeling method, and TRPV4, C-Kit, and P2X5 protein expression levels in bladder tissue were detected by Western blot.

RESULTS

Compared with the sham operation group, the maximum bladder capacity and bladder compliance of rats in the model group were increased (P<0.01), the leak point pressure, ATP content, the possitive expression rates of C-Kit and P2X5, and the protein expression levels of TRPV4, C-Kit, P2X5 in bladder tissue were decreased (P<0.01). In comparison with the model and combination groups, the Yiyuan moxibustion group showed a decrease in maximum bladder capacity and bladder compliance (P<0.01), an increase in leakage point pressure, ATP content, the possitive expression rates of C-Kit and P2X5, and TRPV4, C-Kit, and P2X5 protein expression levels (P<0.01, P<0.05)；However, these indicators showed opposite trends in the inhibitor group (P<0.01, P<0.05).

CONCLUSIONS

Yiyuan moxibustion can improve the urodynamics and bladder function in rats with bladder detrusor nonreflective after SCI, which may be related to its effect in activating the TRPV4 channel in bladder tissue, promoting the release of ATP from bladder epithelium, thus increasing the expression of bladder Cajal interstitial cells and their purinergic P2X5 receptors.

[Efficacy differences between electroacupuncture and moxibustion for neurogenic bladder after spinal cord injury: a randomized controlled trial]

OBJECTIVE

To compare the clinical efficacy between electroacupuncture(EA) and moxibustion for neurogenic bladder (NB) after spinal cord injury (SCI).

METHODS

One hundred and twenty patients with NB after SCI were randomly divided into an EA group, a moxibustion group, and an intermittent catheterization group, with 40 patients in each group. The patients in the intermittent catheterization group were treated with routine treatment and intermittent catheterization, while the patients in the EA group and the moxibustion group were treated with additional treatments of EA (discontinuous wave, with a frequency of 1.3-1.6 Hz, and intensity based on patient tolerance) and moxibustion, respectively. The acupoints used in both groups were Zhongji (CV 3) and Guanyuan (CV 4), bilateral Zusanli (ST 36), Yinlingquan (SP 9), and Baliao points. Each session lasted for 30 min, once daily, six times a week, for a total of six weeks.The maximum bladder capacity (MBC), residual urine vdume (RUV), detrusor pressure (Pdet) during the filling phase, bladder compliance (BC), maximum renal pelvis separation width of both kidneys, urine white blood cell count, TCM syndrome score, and World Health Organization quality of life assessment-BREF (WHOQOL-BREF) score were compared before and after treatment in the 3 groups. The number of patients in each group who achieved bladder functional balance was recorded, and the clinical efficacy was assessed after treatment.

RESULTS

After treatment, the MBC, Pdet, BC, and WHOQOL-BREF scores in the EA group and the moxibustion group were increased (P<0.05), while the RUV, maximum renal pelvis separation width of both kidneys, urine white blood cell count, and TCM syndrome scores were decreased (P<0.05, P<0.01). In the intermittent catheterization group, MBC, RUV, maximum renal pelvis separation width of both kidneys, and urine white blood cell count were decreased (P<0.05), while BC and WHOQOL-BREF score were increased (P<0.05) after treatment. After treatment, the MBC, Pdet, BC, and WHOQOL-BREF scores in the EA group and the moxibustion group were higher than those in the intermittent catheterization group (P<0.05), while the RUV and TCM syndrome scores were lower than those in the intermittent catheterization group (P<0.05). Moreover, after treatment, the MBC and Pdet in the moxibustion group were higher than those in the EA group (P<0.05), while the RUV, maximum renal pelvis separation width of both kidneys, and TCM syndrome score in the EA group were lower than those in the moxibustion group (P<0.05). The number of patients who achieved bladder functional balance after treatment in the EA group and the moxibustion group was higher than that in the intermittent catheterization group (P<0.05). The cured and effective rate was 85.0% (34/40) in the EA group and 82.5% (33/40) in the moxibustion group, which were both higher than 65.0% (26/40) in the intermittent catheterization group (P<0.05), there was no significant difference between the EA group and the moxibustion group (P>0.05).

CONCLUSION

EA and moxibustion could effectively improve the functional state of bladder in patients with NB after SCI. EA is more effective in reducing residual urine volume and excessive activity of the urethral sphincter, and relieving TCM syndromes, while moxibustion is more effective in increasing the pressure of the detrusor during the filling period and establishing the detrusor reflex.

[IL-8 Links NF-κB and Wnt/β-Catenin Pathways in Persistent Inflammatory Response Induced by Chronic Helicobacter pylori Infection]

Helicobacter pylori (H. pylori) infection can cause persistent inflammatory response in human gastric mucosal epithelial cells, which may result in the occurrence of cancer. However, the underlying mechanism of carcinogenesis has not been elucidated yet. Herein, we established the models of chronic H. pylori infection in GES-1 cells and C57BL/6J mice. Interleukin 8 (IL-8) level was detected by ELISA. The expression of NF-κB p65, IL-8, Wnt2 and β-catenin mRNA and proteins was evaluated by real-time PCR, Western blotting, immunofluorescence staining, and immunohistochemistry. The infection of H. pylori in mice was evaluated by rapid urease test, H&E staining and Warthin-Starry silver staining. The morphological changes of gastric mucosa were observed by electron microscopy. Our results showed that in H. pylori infected gastric mucosal cells along with activation of NF-κB signaling pathway and increase of IL-8 level, the expression of Wnt2 was also increased significantly, which preliminarily indicates that IL-8 can positively regulate the expression of Wnt2. Studies in chronic H. pylori infected C57BL/6J mice models showed that there was an increased incidence of premalignant lesions in the gastric mucosa tissue. Through comparing changes of gastric mucosal cell ultrastructure and analyzing the relationship between NF-κB signaling pathway and Wnt2 expression, we found that H. pylori infection activated NF-κB signal pathways, and the massive release of IL-8 was positively correlated with the high expression of Wnt2 protein. Subsequently, the activated Wnt/β-catenin signal pathways may be involved in the malignant transformation of gastric mucosal cells. Collectively, H. pylori chronic infection may continuously lead to persistent inflammatory response: activate NF-κB pathway, promote IL-8 release and thereby activate Wnt/β-catenin pathway. IL-8 probably plays an important role of a linker in coupling these two signal pathways.

[Clinical features and related factors of invasive pulmonary aspergillosis in patients with acute exacerbation of chronic obstructive pulmonary disease]

Objective: To study the clinical features and related factors of invasive pulmonary aspergillosis (IPA) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: This retrospective study enrolled patients hospitalized for AECOPD in ten tertiary hospitals of China from September 2017 to July 2021. AECOPD patients with IPA were included as case group, AECOPD patients without IPA were randomly selected as control group from the same hospitals and same hospitalization period as the patients with IPA using the random function in the software of Microsoft Excel 2003, at a ratio of 2∶1. The clinical characteristics, treatment and outcome were compared between the two groups. Binary logistic regression model was used to analyze the factors associated with IPA in AECOPD patients. Results: A total of 14 007 inpatients with AECOPD were included in this study, and 300 patients were confirmed to have IPA, with an incidence rate of 2.14%. According to the above matching method, 600 AECOPD patients without aspergillus infection were enrolled as the control group. The age of the case group and the control group were (72.5±9.7) and (73.5±10.3) years old, with 78.0%(n=234) male and 76.8%(n=461) male, respectively. There were no significant differences in age and gender composition between the two groups (all P>0.05). The prognosis of case group was significantly worse than that of the control group, with longer hospital stay [M(Q₁,Q₃)], [14 (10-20) d vs 11 (8-15) d, P<0.001], higher ICU admission rate [16.3% (49 case) vs 10.0% (60 case), P=0.006], higher in-hospital mortality [4.0% (12 cases) vs 1.3% (8 cases), P=0.011], and higher hospitalization costs (28 000 ¥ vs 13 700 ¥, P<0.001). The smoking index of the case group and proportions of patients with diabetes mellitus, chronic pulmonary heart disease in the case group were significantly higher than those in control group (all P<0.05). In terms of clinical features, the proportions of patients with cough, expectoration, purulent sputum, hemoptysis and fever in the case group were higher than those in the control group, the serum albumin was significantly lower than that in the control group, and the proportions of patients with bronchiectasis and pulmonary bullae on imaging were significantly higher than those in the control group (all P<0.05). Diabetes (OR=1.559, 95%CI: 1.084-2.243), chronic pulmonary heart disease (OR=1.476, 95%CI: 1.075-2.028), bronchiectasis (OR=1.506, 95%CI: 1.092-2.078), pulmonary bullae (OR=1.988, 95%CI: 1.475-2.678) and serum albumin<35 g/L (OR=1.786, 95%CI: 1.325-2.406) were the related factors of IPA in patients with AECOPD. Conclusions: The incidence of IPA in AECOPD patients is relatively high and the prognosis of these patients is worse. Diabetes, chronic pulmonary heart disease, bronchiectasis, pulmonary bulla, hypoproteinemia are the related factors of IPA in patients with AECOPD.

Differentiation between atypical sinonasal non-Hodgkin's lymphoma and inverted papilloma

AIM

To seek additional magnetic resonance imaging (MRI) features to improve the accuracy of differentiation between atypical sinonasal non-Hodgkin's lymphoma (NHL) and inverted papilloma (IP) using conventional MRI and apparent diffusion coefficient (ADC) maps.

MATERIALS AND METHODS

MRI examinations from 44 atypical cases (21 NHLs and 23 IPs) in sinonasal regions were reviewed retrospectively. Imaging features included tumour laterality, extension, T1-weighted imaging (WI)/T2WI signal intensity homogeneity and ratios, enhancement homogeneity and ratios, and ADC_mean.

RESULTS

In cases of NHL, homogeneous signal intensity was often observed on T2WI, which was homogeneous and significantly less enhanced than the turbinate, with lower ADC_mean. Whereas in IPs, heterogeneous signal intensity was seen on T2WI, which was heterogeneous and of comparable enhancement to the turbinate, and higher ADC_mean values were commonly seen. An ADC_mean cut-off point of 1.10 × 10^-3 mm²/s achieved 100% sensitivity, 90% specificity, and 90% accuracy. In addition, special features were observed that support the distinction between the two tumours, including intestinal pattern enhancement in NHL and spot-like appearance on T2WI and enhancement in IP.

CONCLUSIONS

ADC_mean was the most valuable metric for differentiating between the atypical sinonasal NHLs and IPs.

Utilising clinical data to personlaise boundary conditions significantly improves the accuracy of angiography based virtual FFR

Background

Angiography-derived computed (virtual) fractional flow reserve (vFFR) permits the assessment of coronary physiology without the need for a pressure wire or hyperaemia. However, accuracy is limited by assumptions made about coronary microvascular resistance (CMVR) [1]. We hypothesised that machine learning may allow us to “tune” our estimate of the CMVR to increase the accuracy of vFFR.

Purpose

To determine whether routine clinical data can personalise CMVR and improve the accuracy of vFFR on an individual case basis.

Methods

Patients with chronic coronary syndromes underwent coronary angiography with FFR assessment. Vessel-specific CMVR was computed using a 3D- computational fluid dynamics simulation with invasively measured proximal and distal pressures. Predictive models were created using non-linear autoregressing moving average with exogenous inputs (NARMAX) modelling with computed CMVR as the dependent variable. vFFR was computed using previously described methods [2]. Three simulations were run, using: 1) a generic CMVR value (Model A); 2) a NARMAX-predicted CMVR based upon a panel of simple clinical data (Model B); and 3) a NARMAX-predicted CMVR incorporating echocardiographic data (Model C). The diagnostic and quantitative accuracy of each model was compared with directly measured FFR.

Results

Eighty four patients underwent coronary angiography with FFR assessment in 157 vessels. Mean age was 64 (±0.1) years and 64 (76%) were male. Mean FFR was 0.79 (±0.15). Mean CMVR was 1.01e+10 Pa/m3 s–1. vFFR error with Model A was ±0.10, with Model B was ±0.07 (p&lt;0.001) and with Model C was ±0.05 (p&lt;0.001) (Table 1).

Conclusion

vFFR is dependent upon not only the epicardial stenosis, but also the CMVR, estimation of which can be personalised based upon clinical and echocardiographic data. This can be used to increase the accuracy of vFFR.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): British Heart Foundation Clinial Research Training FellowshipNIHR i4i grant Table 1

[Liver histological status and clinic outcome in HBeAg-negative chronic hepatitis B with low viral load]

Objective: To retrospectively analyze the serological, virological, biochemical, liver histological status and clinical outcomes in HBeAg-negative chronic hepatitis B (CHB) patients with low HBV viral load, and to explore the necessity of antiviral therapy for these patients. Methods: A total of 99 HBeAg-negative CHB patients with HBV DNA level < 4 lg copies/ml who performed liver biopsy at the baseline were enrolled from the follow-up cohort. Among them, 23 cases received the second liver biopsy during follow-up. The relationships among the degree of inflammation and fibrosis of liver tissues, the status of HBsAg and HBcAg, age, gender, family history, HBV DNA load, serological markers and other indicators were analyzed. The pathological differences between two liver biopsy examinations were compared. The effect of nucleos(t)ide analogues (NAs) treatment on patient's clinical outcomes were analyzed. For multivariate analysis, a binary logistic regression model was performed. Log-rank test was used to compare the cumulative incidence of hepatocellular carcinoma (HCC) in NAs-treated and non-NA streated patients. Results: Baseline liver histology status showed that 58.6% (58/99) patients had obvious liver tissue damage in their baseline liver tissue pathology (G≥2 and /or S≥2). Univariate logistic regression analysis showed that a liver cirrhosis (LC) family history, a HBsAg-positive family history, baseline alanine aminotransferase and aspartate aminotransferase levels were positively correlated factors for liver tissue damage. Multivariate logistic regression analysis showed that a LC family history was the main risk factor for liver tissue damage. Twenty-three cases had received a second liver biopsy after an interval of 4.5 years. In 10 untreated cases, the second liver biopsy results showed the rate of obvious liver tissue damage (G≥2 and/ or S≥2) increased from 50.0% to 90.0%. In the other 13 cases who received NAs treatment, the second liver biopsy showed improvement in liver histology, and the rate of obvious liver tissue damage decreased from 61.5% to 46.2%. The 5-year HCC cumulative incidence in non-NAs-treated patients was significantly higher than that of in NAs-treated patients (17.7% vs. 3.8%, P = 0.046). Conclusion: For most HBeAg-negative CHB patients with low viral load, liver tissue pathology result suggests that it meets the indications for antiviral therapy, especially in patients with a LC familial history. Without antiviral therapy, liver tissue damage for these patients will progressively worse with the high incidence of HCC. Therefore, it is suggested that antiviral therapy should be started as soon as possible for the HBeAg-negative CHB patients with low viral load regardless of the alanine aminotransferase level, especially in patients over 30 years-old with a LC or HCC family history.

Altered functional connectivity among default, attention, and control networks in idiopathic generalized epilepsy

Numerous resting-state fMRI studies have demonstrated altered functional connectivity within canonical intrinsic connectivity networks (ICNs) in patients with idiopathic generalized epilepsy (IGE). It is possible that the widespread ICN abnormalities on electroencephalography in IGE derive from abnormal functional interactions between ICNs. To test this possibility, we explored the functional connectivity between the subnetworks of the default mode network (DMN), attention network (ATN), and frontoparietal control network (FPN) using independent component analysis of resting-state fMRI data collected from 27 patients with IGE characterized by generalized tonic-clonic seizures (GTCS) and 29 matched healthy controls. It was observed that the left FPN exhibited increased connectivity with the anterior DMN and ventral ATN, while the right FPN exhibited increased connectivity with the anterior and posterior DMNs in the patients with IGE-GTCS. Furthermore, the functional connectivity between the anterior DMN and ventral ATN was negative in healthy controls but positive in the patients with IGE-GTCS. In addition, the anterior DMN exhibited increased intranetwork functional connectivity in the right frontal pole in IGE-GTCS. These findings suggest that IGE-GTCS is likely associated with a disrupted brain organization probably derived from abnormal functional interactions among ICNs. Furthermore, the alterations in the functional architecture of the ICNs may be related to deficits in mentation and attention in IGE-GTCS, providing informative evidence for the understanding of the pathophysiology of IGE-GTCS.

A century of variation in the dependence of Greenland iceberg calving on ice sheet surface mass balance and regional climate change

Iceberg calving is a major component of the total mass balance of the Greenland ice sheet (GrIS). A century-long record of Greenland icebergs comes from the International Ice Patrol's record of icebergs (I48N) passing latitude 48° N, off Newfoundland. I48N exhibits strong interannual variability, with a significant increase in amplitude over recent decades. In this study, we show, through a combination of nonlinear system identification and coupled ocean–iceberg modelling, that I48N's variability is predominantly caused by fluctuation in GrIS calving discharge rather than open ocean iceberg melting. We also demonstrate that the episodic variation in iceberg discharge is strongly linked to a nonlinear combination of recent changes in the surface mass balance (SMB) of the GrIS and regional atmospheric and oceanic climate variability, on the scale of the previous 1–3 years, with the dominant causal mechanism shifting between glaciological (SMB) and climatic (ocean temperature) over time. We suggest that this is a change in whether glacial run-off or under-ice melting is dominant, respectively. We also suggest that GrIS calving discharge is episodic on at least a regional scale and has recently been increasing significantly, largely as a result of west Greenland sources.

The dependence of extracted current on discharge gas pressure in neutral beam ion sources on HL-2A tokamak

The discharge gas pressure is a key factor to influence the extracted current of ion source. In this paper, the dependence of extracted current on discharge gas pressure was investigated in detail at different arc discharge currents. The discharge gas pressure with a very broad range (0.1 Pa-2.7 Pa) was scanned for the first time. It is turned out that, with the increasing of discharge gas pressure, the extracted current increases and the arc voltage decreases at different arc currents; however, when the discharge gas pressure exceeds a certain value, the extracted current decreases. For the same discharge gas pressure, the higher the arc current, the higher the arc voltage and the extracted current are. The arc efficiency was also calculated, and its dependence on gas pressure was almost the same with the dependence of extracted current on gas pressure, but at the same discharge gas pressure, the lower the arc current, the higher the arc efficiency is and the lower the extracted current is.

Analysis of glutathione peroxidase 1 gene polymorphism and Keshan disease in Heilongjiang Province, China

Keshan disease (KD) is an endemic cardiomyopathy associated with selenium deficiency. Recent studies indicate that glutathione peroxidase 1 (GPx1) mutation decreases GPx activity in myocardial cells and increases the risk of KD. To further clarify the correlation between GPx1 polymorphism and KD, we analyzed GPx1 polymorphism, blood selenium levels and GPx activity in KD patients and healthy controls in Heilongjiang Province. Four and 24 new mutation loci in the promoter and the exon region, respectively, of the GPx1 gene were found in the subjects, in contrast with the previously reported loci. There were no significant differences in the mutation frequency of these loci between the KD group and controls (chi-square test; P > 0.05). However, the mutation frequency of exon 474 was higher in the KD group (7/36) than in controls (2/41), and GPx activity was lower in the mutation group (90.475 ± 23.757 U/L) than in the non-mutation group (93.947 ± 17.463 U/L). Further investigation is necessary to clarify a possible causality between GPx1 exon 474 mutation and KD.

Antiapoptotic and antioxidant effects of rosmarinic acid in astrocytes

The protective effects of rosmarinic acid (RA), a polyphenolic compound, on apoptosis induced by hydrogen peroxide in astrocytes were studied. Pretreating cells with RA significantly increased cell viability and decreased apoptosis rate induced by H2O2. The antiapoptotic effect of RA was further confirmed by increase of mitochondrial membrane potential and inhibition of caspase-3 activity. RA also attenuated cellular oxidative stress by decreasing the amount of reactive oxygen species and malondialdehyde. Results clearly show that RA was able to attenuate H2O2-induced cell injury by its antiapoptotic and antioxidant activity.

Effect of PYCNOGENOL on the toxicity of heart, bone marrow and immune organs as induced by antitumor drugs

PYCNOGENOL is a mixture of water-soluble bioflavonoids extracted from the bark of pine trees growing in the southwest coastal region of France. In the present paper the effects of PYCNOGENOL (Pyc) on the toxicity of bone marrow, heart and immune organs induced by anticancer drugs were investigated, in mice. The following results were obtained: 1. Pyc at the orally-administered dose of 200 and 150 mg/kg body wt. markedly prevented the elevation of serum creatine phosphokinase (CPK) activity and the decrease of heart rate in mice treated with doxorubicin (Dox); 2. Pyc at 100 and 150 mg/kg body wt. significantly antagonized the inhibition of DNA synthesis in thymus induced by subcutaneous injection of cyclophosphamide (Cyc); 3. Pyc at 150 and 200 mg/kg body wt. markedly induced increase of erythrocytes and hemoglobin, but had no effect on leukopenia, in Cyc-treated mice; and 4. Pyc has no antagonizing effect on the anticancer activity of Dox and Cyc. All the results suggest that Pyc possesses a protective effect on the cardiotoxicity of Dox and the inhibition of thymus DNA synthesis induced by Cyc in mice.

Molecular subtyping of Staphylococcus aureus from an outbreak associated with a food handler

On 6 May 2000, a staphylococcal food poisoning outbreak occurred at a high school, affecting 10 of the 356 students who attended the breakfast. Twenty-seven Staphylococcus aureus isolates, producing enterotoxin A (SEA), SEB-, or non-SEA-E, were recovered from 7 patients, 2 food handlers and left-overs. To investigate the outbreak, we genotyped the isolates by using pulsed-field gel electrophoresis (PFGE) and three PCR-based techniques: inter-IS256 PCR typing, protein A gene (spa) typing, and coagulase gene restriction profile (CRP) analysis. Our results show that PFGE was the most discriminatory technique, whereas the three PCR-based techniques were insufficient in the discriminatory power to distinguish the S. aureus isolates from the outbreak. Based on the enterotoxin-producing types and the results of genotyping, three distinct types of strains (A1111, B2221 and N3221) were designated. Both the A1111 and B2221 strains were found in the specimens from the patients and a hand lesion of a food handler, suggesting that the source of contamination for the outbreak was most likely originated from a food handler.

Anisotropic magnetocaloric effect in nanostructured magnetic clusters

We report the first experimental observation of anisotropic magnetocaloric effect (MCE) in the Fe8 clusters. It is found that the magnetic anisotropy plays a very important role in the determination of the magnetocaloric effect. The maximum and minimum MCE's are observed when the applied magnetic fields are parallel and perpendicular to the easy axis, respectively. The quantum spin Hamiltonian of a Fe8 cluster is used to calculate the partition function and the magnetization in a range of temperature and magnetic field. Excellent quantitative agreement between the experimental data and calculation is observed.

Molecular epidemiology of a Shigella flexneri outbreak in a mountainous township in Taiwan, Republic of China

An outbreak of shigellosis occurred in a township of Nantou Conuty in central Taiwan from August to October in 1996. The infections extended to two neighboring townships and continued to the end of 1996. Forty cases were confirmed during the period, in contrast to only one confirmed case in Nantou County in 1996 before the outbreak. All of these 41 cases in 1996 were identified as infections with Shigella flexneri serotype 2a. In order to trace the source of the infections, the 41 isolates recovered were analyzed by plasmid profile and pulsed-field gel electrophoresis (PFGE). There was no correlation between the plasmid profile results and the PFGE results, and the latter were used for subtyping of the 41 isolates. Twenty-two isolates (53%) had the same NotI and XbaI PFGE patterns, and 4 isolates (10%) had an additional unstable plasmid band in their NotI patterns but otherwise had the same NotI and XbaI patterns as the 22 isolates. These 26 isolates were designated the outbreak strain, and of these, 24 appeared in eight villages in one township and 2 appeared in a neighboring township. Fourteen of the remaining 15 isolates, including the isolate recovered 7 months before the outbreak, had both NotI and XbaI PFGE patterns closely related to those of the outbreak strain, indicating that Shigella infections were endemic in the area. By tracing the first isolation dates of the outbreak strain in individual villages and the neighboring township, it was found that the strain spread along the major arterial road and its branch road as time passed. Our molecular typing results and epidemiological data demonstrated the endemic nature of the outbreak strain as well as a person-to-person mode of transmission for the widespread infections the strain caused.

Comparison of pulsed-field gel electrophoresis and coagulase gene restriction profile analysis techniques in the molecular typing of Staphylococcus aureus

Pulsed-field gel electrophoresis (PFGE) and coagulase gene restriction profile (CRP) analysis techniques were used to analyze 71 Staphylococcus aureus isolates recovered from nine food-borne disease outbreaks. Twenty-two PFGE profiles and 11 CRPs were identified, with discrimination indices of 0.86 and 0.72, respectively. In addition, the variable regions of the coagulase genes of 39 isolates were sequenced and showed extensive identity, indicating that this is not an efficient alternative for the molecular typing of S. aureus.

[Protective action of corynoline, acetylcorynoline and protopine against experimental liver injury in mice]

Oral administration of two doses of corynoline, acetylcorynoline or protopine at 50 and 100 mg.kg-1 in an interval of 8 to 24 h before i.p. injection of CCl4, acetaminophen or thioacetamide significantly impeded the elevation of serum transaminase (SGPT) and liver damage in mice. The three compounds were found to inhibit CCl4-induced microsomal lipid peroxidation and CCl4 conversing to carbon monoxide in liver microsomes in vitro. Of these compounds, acetylcorynoline was shown to be more potent than corynoline and protopine. In addition, all the three compounds exhibited biphasic effects on the hepatic cytochrome P450, i.e. inhibition followed by induction, in mice.

[Effects of 16 drugs on immunological liver injury induced by BCG + lipopolysaccharides in mice]

AIM

To evaluate anti-hepatitis drugs.

METHODS

Mice were injected i.v. with viable BCG 5 x 10(7) (live) bacilli/mouse, after 10 d, i.v. lipopolysaccharides (LPS) 5-10 micrograms/mouse. Serum aminotransferase levels and liver tissue were examined 10 h after i.v. LPS. Sixteen drugs were evaluated in this model.

RESULTS

The level of AlaAT and AspAT were increased markedly. Submassive necrosis and infiltrations of granulocytes and lymphocytes were seen, which were not recovered till 14 d after i.v. LPS. Administration of interferon alpha-2a, Ara-AMP, hepatocyte growth factor, biphenyl dimethyl dicarboxylate, bicyclol, prednisolone, and cyclophosphamide for 10 d prior to i.v. LPS suppressed the elevation of serum AlaAT and AspAT.

CONCLUSION

The model of immunological liver injury reproduced by i.v. BCG + LPS in mice may be used for evaluating anti-hepatitis drugs.

Hepatoprotective effect of SY-640, a novel acetamide derivative, on Propionibacterium acnes and lipopolysaccharide-induced liver injury in mice

The hepatoprotective effect of SY-640 on Propionibacterium acnes and lipopolysaccharide-induced liver injury in mice and its protective mechanism were examined. Oral administration of SY-640, 150 mg/kg once daily for 7 days, significantly inhibited Propionibacterium acnes and lipopolysaccharide-induced liver injury, but a single administration was without effect. Liver-infiltrating cells (T-lymphocytes and macrophages) play an important role in Propionibacterium and lipopolysaccharide-induced liver injury and express a higher level of leukocyte function-associated antigen-1. SY-640 inhibited the number of liver-infiltrating cells and attenuated the increased expression of leukocyte function-associated antigen-1 on these cells. Tumor necrosis factor-alpha mediated Propionibacterium acnes and lipopolysaccharide-induced liver injury, and SY-640 inhibited the elevation of the serum tumor necrosis factor-alpha concentration after injection of lipopolysaccharide in Propionibacterium acnes-primed mice. The putative effects of SY-640 are inhibitory effects on infiltration into the liver and on activation of T-lymphocytes and macrophages after Propionibacterium acnes-priming, and attenuation of expression of cell adhesion molecules such as leukocyte function-associated antigen-1. The immunological effect of SY-640 is likely to be closely related to the inhibition of Propionibacterium and lipopolysaccharide-induced liver injury.

Superinfection-induced apoptosis and its correlation with the reduction of viral progeny in cells persistently infected with Hz-1 baculovirus

Differential induction of necrosis or apoptosis was found upon challenge of cells of the insect Spodoptera frugiperda productively or persistently infected with Hz-1 baculovirus, respectively. Unlike parental SF9 cells, which were essentially all killed by virally induced necrosis, persistently infected cells underwent a process of massive cell death by apoptosis; cells which were not killed by apoptosis then reestablished a cell monolayer. Upon viral challenge, the yield of viral progeny was reduced greatly in persistently virus-infected cells but not in parental cells. Immunolabelling of individual cells revealed that upon viral challenge, production of viral progeny was detectable only in necrotic cells and not in apoptotic cells. These results indicated that induction of apoptosis greatly reduces the yield of viral progeny in cells persistently infected with Hz-1 baculovirus. This is the first report of apoptosis induction in persistently infected cells upon viral superinfection.

Vector competence of Aedes albopictus and Ae. aegypti (Diptera: Culicidae) to dengue 1 virus on Taiwan: development of the virus in orally and parenterally infected mosquitoes

The vector competence in Ae. aegypti (L.) and Ae. albopictus (Skuse) from southern Taiwan to the dengue 1 virus was studied to elucidate the distribution of dengue infection during the 1987-1988 outbreak. The brain of Ae. aegypti was infected as early as 3 d after intrathoracic inoculation. The esophagus and the proboscis (tissues within the labium) were infected 5 d after inoculation. The salivary gland was highly susceptible to the virus, but no specific infection site was found. Gangli, muscles, and diverticula within the thorax were not infected. In the abdominal area, the ventral diverticula, Malpighian tubules, ganglia, and the dorsal vessel were not infected. However, the entire gut was susceptible to dengue 1 virus, although it was not infected simultaneously. Only a certain type of midgut epithelial cells was infected by the virus. The ovarioles, oviducts, and accessory glands frequently were infected. However, the spermathecae were not infected, perhaps because of the chitin-rich outer layer. Infections of the testes, vas deferens, seminal vesicles, and accessory glands of males also were detected in this study. The tissues of the proboscis were never infected in Ae. albopictus but frequently were infected in Ae. aegypti, indicating that the virus may escape the salivary gland barrier more efficiently in Ae. aegypti than in Ae. albopictus. When these mosquitoes were fed on hanging drops, the salivary gland infection and transmission rates of Ae. aegypti were always higher than those of Ae. albopictus. On Taiwan, Ae. aegypti appears to be a more competent vector in the transmission of the dengue 1 virus than Ae. albopictus.

Antioxidant activity of two dibenzocyclooctene lignans on the aged and ischemic brain in rats

The effects of two dibenzocyclooctene lignans on peroxidative damage of aging and ischemic rat brain were studied. Incubation of eight-month-old rat brain mitochondria and membrane suspension with Fe(2+)-cysteine resulted in the formation of malondialdehyde (MDA) and decrease of ATPase activity. Schisanhenol (Sal) (10(-4) M) completely inhibited the peroxidative damages of brain mitochondria and membrane of rats. The swelling and disintegration of brain mitochondria, as well as the reduction of brain membrane fluidity induced by Fe(2+)-cysteine were also prevented by Sal. The results of imitative experiment of ischemia and reperfusion of brain mitochondria and membrane in vitro indicated that Sal significantly impeded production of MDA and loss of ATPase activity induced by reoxygenation following anoxia. Oral administration of Sal induced increase of cytosol glutathione-peroxidase of brain in mice under the condition of reoxygenation following anoxia. The other compound schizandrin (Sin B) also has similar activity. But its potency is weaker than that of Sal. All these results indicate that Sal and Sin B have protective action against oxidative stress.

Dose-dependent reduced haloperidol/haloperidol ratios in schizophrenic patients

Plasma haloperidol (HAL) and reduced HAL (RHAL) concentrations were measured in 113 Chinese schizophrenic patients. Daily doses of HAL ranged from 8 to 65 mg. Samples were obtained under steady-state conditions and drawn 10-12 hours after the bedtime dose and before the morning dose. In all, 313 blood samples were collected. Multiple samples were obtained at the same doses in 63 patients and at two or three different doses in 31 patients. HAL and RHAL concentrations were assayed by high performance liquid chromatography. Interpatient variation in plasma HAL levels at a given dosage was up to sixfold. However, there was a high positive correlation between plasma levels and daily dosages with the equation of HAL plasma level (ng/ml) = 0.88 x dosage (mg/day) -0.56 or 46.0 x dosage (mg/day/kg) + 0.28. The expected values are about 15-55% higher than those obtained from non-Chinese patients as reported in the literature. The RHAL/HAL ratios were dose-dependent. The greater the dose used, the higher the ratio. An upper therapeutic limit of plasma HAL level is suggested to be 25 ng/ml, which can be achieved at dosages about 30 mg/day in most Chinese patients. Based upon the dose-dependent increase in RHAL/HAL ratios, the importance of RHAL in determining the therapeutic benefit of HAL treatment is discussed.