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Homopolymer PAN and triblock copolymer PAN-<b>b</b>-PMMA-<b>b</b>-PAN synthesized by RAFT polymerization were used to fabricate activated hierarchical porous carbon membranes by combining phase inversion, carbonization, and HNO3 activation method; during the preparation process, a lot of micro- and meso-pores generated because of phase separation of PAN and microphase separation of PAN-<b>b</b>-PMMA-<b>b</b>-PAN. The hierarchical porous structure shortened ions transport paths and facilitated the rapid migration of electrolyte ions. When the polymer membrane was prepared by the casting solution with 5 wt% of PAN-<b>b</b>-PMMA-<b>b</b>-PAN and the electrochemical performance was tested at the current densities from 0.5 to 5 A g−1, a high-end specific capacitance of 297.0 F g−1 and a capacitance retention of 75% were obtained in three-electrode configuration; this specific capacitance remained above 90% of initial value after 2000 cycles at 2 A g−1 in 6 M KOH aqueous solution. Moreover, symmetric supercapacitors assembled with the prepared materials achieved high energy density (15.8 Wh Kg−1) and power density (4000 W Kg−1) in 1 M Na2SO4 solution. The unique features and structures endowed the electrode membrane with good capacitive performance in both three-electrode and two-electrode configuration, which can be used as electrode membranes for high-performance energy storage devices and other applications.<br><br>Display Omitted<br>• An electrode membrane of activated hierarchical porous carbon was fabricated • Micro- and meso-pores generated due to the phase and microphase separation. • Effects of copolymer concentration on structure and performance were studied • High electrochemical performance for supercapacitor was obtained.
Addicted drugs like nicotine affect autonomic nervous system that results in arrhythmia and other cardiovascular diseases. Notable effects of Zen meditation on autonomic nervous system have been reported during the past decade. Holistic Detox Association (HDA) in Taiwan offered Zen-meditation program to drug addicts as the core scheme among a variety of drug addiction treatments. This paper reports the results of quantifying the cardiorespiratory interactions and autonomic nervous system function to evaluate the on-site effect of Zen meditation on drug rehab. Methods and schemes for quantifying time-domain heart rate variability were employed to electrocardiograph and respiratory signals. Peak-valley method was developed to quantify the respiratory sinus arrhythmia (RSA) behavior. Poincaré Plot Analysis was adopted to evaluate the cardiorespiratory functioning. Among 18 voluntary drug addicts during the 10-minute Zen meditation session, about two-third subjects have significant improvement in autonomic nervous system function characterized by heart rate variability (SDNN, RMSSD and pNN50). Group average of RSA increases from 33.43 ms(Rest) to 69.14 ms(AR Zen meditation). Poincaré-plot analysis reveals the improvement of SD1, SD2 and SD2/SD1 by respectively 14.7%, 19.8% and 8.8%. The group averages of all the parameters exhibit significantly positive changes in the 10-minute session of abdominal-respiration Zen meditation. Even the subject with heart transplant showed the improvement of all the quantitative indicators during the AR Zen meditation.
In this study, an environmentally friendly approach for surface modification of polymer membrane was reported, which named surface-initiated electrochemically mediated atom transfer radical polymerization (SI-eATRP). It was triggered after diffusion of a CuI/L activator generated at a working electrode. The introduction of electrochemically mediation can control the polymerization of monomers by a one-electron reduction of an initially added air-stable CuII salt. The reaction was carried out in an electrochemical cell with a three-electrode system at low temperature. Using this technique, hydrophilic polymer brushes of poly(N-vinylpyrrolidone) were grafted onto PES membrane surface. The effects of reaction conditions like polymerization time, monomer concentration, initiator amount, and different monomer on the polymerizations of monomer were investigated in detail. Based on these data, we concluded that the polymerization on polymer membrane surface could be controlled by mediating the reaction condition. Moreover, the precisely controlled polymerization may allow it to serve as excellent model systems for polymer membrane modification, in general, to illustrate the role of electrochemically mediating on the polymerization approach. And the water contact angle of the modified membrane decreased from 89° to 72°. The APTT of the modified membrane increased from 46 s to 81 s. Those results indicated that the surface modification by grafting PVP brushes provided practical application for the PES membranes with high surface properties.
This study examined the effectiveness of a stress coping program based on mindfulness meditation on the stress, anxiety, and depression experienced by nursing students in Korea. A nonequivalent, control group, pre-posttest design was used. A convenience sample of 41 nursing students were randomly assigned to experimental (n=21) and control groups (n=20). Stress was measured with the PWI-SF (5-point) developed by Chang. Anxiety was measured with Spieberger's state anxiety inventory. Depression was measured with the Beck depression inventory. The experimental group attended 90-min sessions for eight weeks. No intervention was administered to the control group. Nine participants were excluded from the analysis because they did not complete the study due to personal circumstances, resulting in 16 participants in each group for the final analysis. Results for the two groups showed (1) a significant difference in stress scores (F=6.145, p=0.020), (2) a significant difference in anxiety scores (F=6.985, p=0.013), and (3) no significant difference in depression scores (t=1.986, p=0.056). A stress coping program based on mindfulness meditation was an effective intervention for nursing students to decrease their stress and anxiety, and could be used to manage stress in student nurses. In the future, long-term studies should be pursued to standardize and detail the program, with particular emphasis on studies to confirm the effects of the program in patients with diseases, such as cancer.
This study examined the effectiveness of a stress coping program based on mindfulness meditation on the stress, anxiety, and depression experienced by nursing students in Korea. A nonequivalent, control group, pre-posttest design was used. A convenience sample of 41 nursing students were randomly assigned to experimental (n=21) and control groups (n=20). Stress was measured with the PWI-SF (5-point) developed by Chang. Anxiety was measured with Spieberger's state anxiety inventory. Depression was measured with the Beck depression inventory. The experimental group attended 90-min sessions for eight weeks. No intervention was administered to the control group. Nine participants were excluded from the analysis because they did not complete the study due to personal circumstances, resulting in 16 participants in each group for the final analysis. Results for the two groups showed (1) a significant difference in stress scores (F=6.145, p=0.020), (2) a significant difference in anxiety scores (F=6.985, p=0.013), and (3) no significant difference in depression scores (t=1.986, p=0.056). A stress coping program based on mindfulness meditation was an effective intervention for nursing students to decrease their stress and anxiety, and could be used to manage stress in student nurses. In the future, long-term studies should be pursued to standardize and detail the program, with particular emphasis on studies to confirm the effects of the program in patients with diseases, such as cancer.
Purpose] Fragmentary studies on characteristics of respiratory muscles are being done to increase respiratory capacity by classifying exercises into voluntary respiratory exercise which relieves symptoms and prevents COPD and exercise using breathing exercise equipment. But this study found changes on respiratory pattern through changes on the activity pattern of agonist and synergist respiratory muscles and studied what effect they can have on body function improvement. [Subjects and Methods] Fifteen subjects in experimental group I that respiratory exercise of diaphragm and 15 subjects in experimental group II that feedback respiratory exercise were randomly selected among COPD patients to find the effective intervention method for COPD patients. And intervention program was conducted for 5 weeks, three times a week, once a day and 30 minutes a session. They were measured with BODE index using respiratory muscle activity, pulmonary function, the six-minute walking test, dyspnea criteria and BMI Then the results obtained were compared and analyzed. [Results] There was a significant difference in sternocleidomastoid muscle and scalene muscle and in 6-minute walk and BODE index for body function. Thus the group performing feedback respiratory had more effective results for mild COPD patients. [Conclusion] Therefore, the improvement was significant regarding the activity of respiratory muscles synergists when breathing before doing breathing exercise. Although, it is valuable to reduce too much mobilization of respiratory muscles synergists through the proper intervention it is necessary to study body function regarding improvement of respiratory function for patients with COPD.
This study was designed to assess the association between stress, positive affect and catecholamine levels in meditation and control groups. The meditation group consisted of 67 subjects who regularly engaged in mind-body training of "Brain-Wave Vibration" and the control group consisted of 57 healthy subjects. Plasma catecholamine (norepinephrine (NE), epinephrine (E), and dopamine (DA)) levels were measured, and a modified form of the Stress Response Inventory (SRI-MF) and the Positive Affect and Negative Affect Scale (PANAS) were administered. The meditation group showed higher scores on positive affect (p=.019) and lower scores on stress (p<.001) compared with the control group. Plasma DA levels were also higher in the meditation (p=.031) than in the control group. The control group demonstrated a negative correlation between stress and positive affects (r=-.408, p=.002), whereas this correlation was not observed in the meditation group. The control group showed positive correlations between somatization and NE/E (r=.267, p=.045) and DA/E (r=.271, p=.042) ratios, whereas these correlations did not emerge in the meditation group. In conclusion, these results suggest that meditation as mind-body training is associated with lower stress, higher positive affect and higher plasma DA levels when comparing the meditation group with the control group. Thus, mind-body training may influence stress, positive affect and the sympathetic nervous system including DA activity.
PURPOSE:Purpose of this study was to examine the effects of the Mindfulness Meditation program on perceived stress, ways of coping, salivary cortisol level, and psychological stress response in patients with breast cancer.
METHODS:
This was a quasi-experimental study with a non-equivalent control group pre-post test design. Participants in this study were 50 patients who had completed breast cancer treatment (experimental group, 25, control group, 25). The experimental group received the Mindfulness Meditation program for 3 hours/session/ week for 8 weeks. Data were analyzed using χ²-test and t-test for subject homogeneity verification, and ANCOVA to examine the hypotheses.
RESULTS:
The experimental group had significantly lower scores for perceived stress, emotional focused coping, salivary cortisol level, and psychological stress response compared to the control group. However, no significant differences were found between two groups for the scores on problem focused stress coping.
CONCLUSION:
According to the results, the Mindfulness Meditation program was useful for decreasing perceived stress, emotional focused coping, salivary cortisol level, and psychological stress response. Therefore, this program is an effective nursing intervention to decrease stress in patients with breast cancer.
ObjectiveTo assess the effects of a 12-week Tai Chi exercise program on sleep using the sleep spectrogram, a method based on a single channel electrocardiogram (ECG)-derived estimation of cardiopulmonary coupling, previously shown to identify stable and unstable sleep states.
Methods
We retrospectively analyzed 24-h continuous ECG data obtained in a clinical trial of Tai Chi exercise in patients with heart failure. Eighteen patients with chronic stable heart failure, left ventricular ejection fraction ⩽40% (mean [±standard deviation] age, 59±14 years, mean baseline ejection fraction 24%±8%, mean) were randomly assigned to receive usual care (N=10), which included pharmacological therapy and dietary and exercise counseling, or 12 weeks of Tai Chi training (N=8) in addition to usual care. Using the ECG-based sleep spectrogram, we compared intervention and control groups by evaluating baseline and 12-week high (stable) and low (unstable) frequency coupling (HFC & LFC, respectively) as a percentage of estimated total sleep time (ETST).
Results
At 12 weeks, those who participated in Tai Chi showed a significant increase in HFC (+0.05±0.10 vs. −0.06±0.09 % ETST, p=0.04) and significant reduction in LFC (−0.09±0.09 vs. +0.13±0.13 % ETST, p<0.01), compared to patients in the control group. Correlations were seen between improved sleep stability and better disease-specific quality of life.
Conclusions
Tai Chi exercise may enhance sleep stability in patients with chronic heart failure. This sleep effect may have a beneficial impact on blood pressure, arrhythmogenesis and quality of life.
PurposeAlthough the effectiveness of Mindfulness-Based Cognitive Therapy (MBCT) for panic disorder (PD) has been studied previously, data on the predictors of treatment outcomes in MBCT for PD are scarce.
Materials and Methods
Eighty patients with PD were screened to analyze treatment outcomes such as MBCT completion, treatment response, and remission after undergoing MBCT for PD. Sociodemographic characteristics, comorbid personality disorders, and baseline medication doses were examined. The study administered the Panic Disorder Severity Scale, Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale and Anxiety Sensitivity Inventory-Revised to patients at baseline and at eight weeks.
Results
Sixty-five participants were enrolled in the present study. Comorbid personality disorder was significantly associated with MBCT non-completion. We found that anxiety sensitivity (AS) improvement after an eight week MBCT program was a statistically significant factor associated with treatment response. Using logistic regression analysis, AS improvement after MBCT showed significant association with PD remission after MBCT.
Conclusion
Comorbid personality disorders of participants could be a potential predictor of MBCT non-completion. Furthermore, AS improvement after MBCT may predict treatment response and remission after MBCT for PD. However, better designed studies with a larger number of patients are needed to confirm our findings.
The relation between brain activity and the immune system was evaluated by assessing immune responses in 20 healthy women who manifested extreme differences in the asymmetry of frontal cortex activation. One group showed extreme and stable left frontal activation; the other group showed extreme and stable right frontal activation. As predicted, women with extreme right frontal activation had significantly lower levels of natural killer cell activity (at effector:target cell ratios of 33:1 and 11:1) than did left frontally activated individuals. This difference did not extend to two other immune measures, lymphocyte proliferation and T-cell subsets. However, higher immunoglobulin levels of the M class were observed in the right frontal group. In this study, the immune patterns could not be accounted for by plasma cortisol levels, anxiety- and depression-related symptomatology, or recent health histories. These findings support the hypothesis that there is a specific association between frontal brain asymmetry and certain immune responses.
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ObjectiveIntolerance of uncertainty (IU) is a transdiagnostic construct in various anxiety and depressive disorders. However, the relationship between IU and panic symptom severity is not yet fully understood. We examined the relationship between IU, panic, and depressive symptoms during mindfulness-based cognitive therapy (MBCT) in patients with panic disorder.
Methods
We screened 83 patients with panic disorder and subsequently enrolled 69 of them in the present study. Patients participating in MBCT for panic disorder were evaluated at baseline and at 8 weeks using the Intolerance of Uncertainty Scale (IUS), Panic Disorder Severity Scale-Self Report (PDSS-SR), and Beck Depression Inventory (BDI).
Results
There was a significant decrease in scores on the IUS (p<0.001), PDSS (p<0.001), and BDI (p<0.001) following MBCT for panic disorder. Pre-treatment IUS scores significantly correlated with pre-treatment PDSS (p=0.003) and BDI (p=0.003) scores. We also found a significant association between the reduction in IU and PDSS after controlling for the reduction in the BDI score (p<0.001).
Conclusion
IU may play a critical role in the diagnosis and treatment of panic disorder. MBCT is effective in lowering IU in patients with panic disorder.
Areas associated with the default mode network (DMN) are substantially similar to those associated with meditation practice. However, no studies on DMN connectivity during resting states have been conducted on meditation practitioners. It was hypothesized that meditators would show heightened functional connectivity in areas of cortical midline activity. Thirty-five meditation practitioners and 33 healthy controls without meditation experience were included in this study. All subjects received 4.68-min resting state functional scanning runs. The posterior cingulate cortex and medial prefrontal cortex were chosen as seed regions for the DMN map. Meditation practitioners demonstrated greater functional connectivity within the DMN in the medial prefrontal cortex area (x y z = 3 39 −21) than did controls. These results suggest that the long-term practice of meditation may be associated with functional changes in regions related to internalized attention even when meditation is not being practiced.
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Ischemic stroke is a primary cause of death and long-term disability all over the world. This disease is resulted from ischemia and hypoxia in brain tissues because of insufficient blood supply and causes a series of physiochemical metabolism disorders and physiological dysfunction. Its high disability ratio has bright huge burdens to society, governments and families. However, there is not efficacious medicine to treat it. In this study, a right middle cerebral artery occlusion was established in rats to observe the multi-path and multi-aspect intervention effects of Tibetan patent medicine Ruyi Zhenbao pills in reducing injuries to Nissl bodies, cerebral edema and inflammatory reactions and preventing cellular apoptosis, in order to lay a foundation for defining its therapeutic mechanism in acute ischemic stroke.;
<p>From Introduction: It is increasingly common for those doing research on meditation to be meditators themselves. Such people are far better equipped than non-meditator researchers to arrive at balanced and well informed conclusions. Textual scholars who meditate are in a position to interpret the textual accounts of meditation intelligibly and realistically, and perhaps to correlate otherwise obscure statements with actual meditative techniques and attainments. Psychologist-meditators, with their training in detached observation and their technical vocabulary, are in a position to formulate accurate and insightful descriptions and interpretations of what they experience in their meditation. Such factors have contributed to the recent rapid growth of well informed writings on Buddhist meditation. The present collection of twenty-eight readings is designed to give meditators, researchers, and general readers ready access to representative samples of those writings, and to the principal relevant texts. The readings are grouped under four headings, arranged in roughly chronological order, as follows. Section I. Pali Sources... Section II. Classical Masters... Section III. contemporary Masters... Section IV. Personal Accounts...</p>
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OBJECTIVES:Emotional support and a stress management program should be simultaneously provided to clients as effective preventive services for healthy behavioral change. This study was conducted to review various relaxation and meditation intervention methods and their applicability for a preventive service program.
METHODS AND RESULTS:
The author of this paper tried to find various relaxation and meditation programs through a literature review and program searching and to introduce them. The 'Relaxation Response' and 'Mindfulness Based Stress Reduction (MBSR)' are the most the widely used meditative programs in mainstream medical systems. Abdominal breathing, Progressive Musclular Relaxation (PMR), Relaxative Imagery, Autogenic Training (AT) and Biofeedback are other well-known techniques for relaxation and stress management. I have developed and implemented some programs using these methods. Relaxation and meditation classes for cancer patients and a meditation based stress coping workshop are examples of this program.
CONCLUSIONS:
Relaxation and meditation seem to be good and effective methods for primary, secondary and tertiary preventive service programs. Program development and standardization and further study are needed for more and wider use of the mind-body approach in the preventive service area of medicine.
Evidence for the effectiveness of mindfulness as a clinical intervention is quickly growing. Much of our current understanding and application of mindfulness within clinical psychology has arisen from dialogue with Buddhist traditions, with the notable exception of Acceptance and Commitment Therapy. We wrote this article with two purposes: (1) to provide a concise review of mindfulness within the Buddhist traditions for interested clinicians and researchers and (2) to explore whether further dialogue between Buddhism and clinical psychology could enhance mindfulness as it is used within clinical psychology. We concluded that mindfulness, as it is understood and applied in Buddhism, is a richer concept than thus far understood and applied in psychology. In addition, within Buddhism the development of mindfulness must be understood in tandem with the development of wisdom, compassion, and ethics. We suggest an operational definition of mindfulness within Buddhism. We also explore implications for clinical psychology and possible future directions for mindfulness research and practice.
Because they generate excellent images, nanoparticles (NPs), especially biosynthesized NPs, provide a new solution for tumor imaging. In this research, we unveil a novel type of biosynthesized NPs featuring multicolor fluorescence. These NPs exhibit little cytotoxicity to cells. The explored NPs, designated Zn-ZFP-GST NPs (Zinc NPs in abbreviation), are generated from leukemia cells treated with a Zn2+ solution, while zinc-finger protein and glutathione S-transferase (GST) were also identified in the Zinc NPs. Under near-UV illumination, the Zinc NPs simultaneously emit green, yellow, and red fluorescence. In addition, the intensity of the fluorescence increases with the existence of sulfides. Besides, the NPs are encapsulated by microvesicles (MVs) shed from the plasma membrane. As observed in whole-body research of nude mice, the NP-MVs migrate via blood circulation and are distinguished by their fluorescent signals. Furthermore, the folic acid (FA) &AVR2 (human VEGF antibody)-coated NP-MVs are exploited to target the tumor location, and the feasibility of this approach has been confirmed empirically. The Zinc NPs shed light on an alternative solution to tumor detection.
Although meditation is increasingly accepted as having personal benefits, less is known about the broader impact of meditation on social and intergroup relations. We tested the effect of lovingkindness meditation training on improving implicit attitudes toward members of 2 stigmatized social outgroups: Blacks and homeless people. Healthy non-Black, nonhomeless adults (N = 101) were randomly assigned to 1 of 3 conditions: 6-week lovingkindness practice, 6-week lovingkindness discussion (a closely matched active control), or waitlist control. Decreases in implicit bias against stigmatized outgroups (as measured by Implicit Association Test) were observed only in the lovingkindness practice condition. Reduced psychological stress mediated the effect of lovingkindness practice on implicit bias against homeless people, but it did not mediate the reduced bias against Black people. These results suggest that lovingkindness meditation can improve automatically activated, implicit attitudes toward stigmatized social groups and that this effect occurs through distinctive mechanisms for different stigmatized social groups.
Activation of the induced receptor for advanced glycation endproducts (RAGE) leads to initiation of NF-κB and MAP kinase signaling pathways resulting in propagation and perpetuation of inflammation. RAGE knock out animals are less susceptible to acute inflammation and carcinogen induced tumor development. We have reported that most forms of tumor cell death result in release of the RAGE ligand, HMGB1. We now report a novel role for RAGE in the tumor cell response to stress. Targeted knockdown of RAGE in the tumor cell, leads to increased apoptosis, diminished autophagy and decreased tumor cell survival . In contrast, overexpression of RAGE is associated with enhanced autophagy, diminished apoptosis and greater tumor cell viability. RAGE limits apoptosis through a p53 dependent mitochondrial pathway. Moreover, RAGE-sustained autophagy is associated with decreased phosphorylation of mTOR and increased Beclin-1/VPS34 autophagosome formation. These findings demonstrate that the inflammatory receptor RAGE plays a heretofore unrecognized role in the tumor cell response to stress. Furthermore, these studies establish a direct link between inflammatory mediators in the tumor microenvironment and resistance to programmed cell death. Our data suggest that targeted inhibition of RAGE or its ligands may serve as novel targets to enhance current cancer therapies.
Stress management is important and various stress management methods are required in the area of clinical preventive services. Although defining stress is somewhat complicated, stress can usually be divided into two concepts, stressors and the stress reaction. Stressors are stimuli that arouse the stress reaction. Examples are disasters, life events requiring changes, and everyday hassles. The stress reaction is often called the 'fight or flight reaction' and is mediated by the sympathetic nervous system and various hormones, including cortisol and catecholamine. Stress is closely related with health behaviors and several chronic diseases. Stress is measured using biological tests or self report, including questionnaires and interviews. Psychosocial Wellbeing Index-Short Form, Brief Ecounter PsychoSocial Instrument-Korean version, Global Assessment of Recent Stress Scale, and Symptom Checklist-90-Revised are examples of questionnaires that are widely used in Korea. Stress coping methods are categorized into stimuli-oriented methods, cognitive-behavioral methods, and mind-body interventions. Relaxation and meditation are widely used mind-body medical interventions. Relaxation Response and Mindfulness-Based Stress Reduction are two of the most widely used meditative programs in the Western mainstream medical system. Abdominal breathing, Progressive Muscular Relaxation, relaxing imagery, Autogenic Training, and biofeedback are other well-known techniques for relaxation and stress management. Relaxation and meditation are effective in improving health behaviors and quality of life, and complement the treatment methods of various chronic diseases, including cardiovascular disorders and cancer. Relaxation and meditation also seem to be effective methods for use in clinical preventive services. Program development, standardization, and further study are necessary for more widespread use of mind-body interventions in the area of clinical preventive services.
The effective, energy-saving and green subcritical fluid extraction (SFE) technology was applied to obtain the oil from <i>Lycium ruthenicum</i> seeds (LRSO). The optimal conditions of extraction parameters were found using response surface methodology with Box-Behnken experimental design. The maximum extraction yield of 21.20% was achieved at raw material particle size of 0.60 mm, extraction pressure of 0.63 MPa, temperature of 50 °C and time of 48 min. Other traditional extraction technologies were comparatively used. The physicochemical property of LRSO was analysed and the chemical compositions indicated that they were rich in unsaturated fatty acid, β-carotene, tocopherols and total phenolics. Furthermore, the antioxidant activity of LRSO was evaluated by scavenging activity of three kinds of radicals (DPPH·, ·OH and O₂⁻·) and lipid peroxidation <i>in vitro</i>. And its results showed the oil had the potential to be a novel antioxidant agent for using in the field of food, pharmaceuticals and cosmetics.<br>Lycium ruthenicum seeds oil (LRSO) was obtained by subcritical fluid extraction (SFE), and the process of SFE was optimized using response surface methodology. LRSO was evaluated by determination of physicochemical property, lipophilic compositions and antioxidant activity. The study revealed the possibility of LRSO as a potential source of valuable product for commercial ventures (food, pharmaceuticals or cosmetics).
<p>This facility enables one to identify the Chinese, Tibetan, and Sanskrit "parallels" or "counterparts" to the suttas of the four main Pali Nikayas - or vice versa. It is designed for those whose interest in the Early Buddhist discourses extends beyond the limits of the Pali Sutta-piṭaka to include the extensive corresponding materials found elsewhere: the Agamas and individual sutras preserved in Chinese, the occasional sutra translations contained in the Tibetan Kanjur, and the numerous published fragments of sutras in Sanskrit and related languages. It is an up-dated and revised successor to Akanuma's <em>Comparative Catalogue of Chinese Agamas & Pali Nikayas</em> (1929), and is the natural starting point in navigating around this vast mass of textual material.</p>
OBJECTIVE: To investigate the xanthones from Tibetan medicine Halenia elliptica and their antioxidant activity.METHODS: Column chromatography over normal phase silica gel, reversed phase silica gel, Sephadex LH-20, and recrystallization techniques were used to isolate and purify constituents from Halenia elliptica. Infrared spectrometry, mass spectrometry, and nuclear magnetic resonance spectrometry were used to identify the structure of compounds. The antioxidant activity was evaluated by measuring the content of malondialdehyde product in mice liver cell microsomal induced by ferrous-cysteine.
RESULTS: Eight xanthones (compound I-VIII) were isolated and identified from the ethyl acetate extract of Halenia elliptica, among which 1,7-dihydroxy-2,3,5-trimethoxyxanthone was a novel compound. Compound I, III at 10 microg/ml and 100 microg/ml could inhibit the production of malondialdehyde in mouse liver microsomes in vitro.
CONCLUSION: Eight xanthones were isolated and they have certain antioxidant activity.