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1.
Int J Tuberc Lung Dis ; 28(2): 73-80, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38303039

ABSTRACT

BACKGROUND: The importance of early intravenous (IV) antibiotic use for Mycobacterium abscessus complex lung diseases (MABC-LD) treatment remains unknown. METHODS: A retrospective multi-centre observational study was conducted in Taiwan. Patients who were diagnosed with and received treatment for MABC-LD from January 2007 to April 2021 were included. Treatment outcome was defined as modified microbiological cure of MABC-LD.RESULTS: Of the 89 enrolled patients, 34 (38.2%) received IV antibiotics as part of the treatment regimen. The median time to IV initiation was 1 day (IQR 1???49); 24 (70.6%) of these patients received IV agents within 4 weeks, defined as early-use. Forty-two (47.2%) patients achieved modified microbiological cure. In the multivariable logistic analysis, early IV antibiotic use was an independent factor associated with modified microbiological cure (aOR 5.32, 95% CI 1.66???17.00), whereas high radiological score (aOR 0.86, 95% CI 0.73???1.00) demonstrated negative association.CONCLUSIONS: In the present study, early use of effective IV antibiotic was prescribed in a low percentage (27%) for MABC-LD. By contrast, early IV antibiotic use was correlated with higher microbiological cure than were late or non-use. Future larger and prospective studies are needed to validate the association.


Subject(s)
Lung Diseases , Mycobacterium Infections, Nontuberculous , Mycobacterium abscessus , Humans , Anti-Bacterial Agents/therapeutic use , Mycobacterium Infections, Nontuberculous/drug therapy , Mycobacterium Infections, Nontuberculous/microbiology , Lung Diseases/drug therapy , Lung Diseases/microbiology , Prospective Studies , Retrospective Studies
2.
Clin Microbiol Infect ; 24(11): 1195-1199, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29458157

ABSTRACT

OBJECTIVES: Clostridium innocuum can cause extraintestinal infection in patients with underlying diseases. The role of C. innocuum in antibiotic-associated diarrhoea (AAD) remains unknown. METHODS: Clinical information of 103 patients from whom C. innocuum was isolated was reviewed. We carried out cellular and animal experiments to examine the pathogenic potential of C. innocuum in AAD. RESULTS: Eighty-eight per cent (91/103) of the 103 patients received antibiotics within 2 weeks of diarrhoea onset. Patients were further classified into two groups, severe colitis and diarrhoea, according to clinical severity level. The mortality rate was 13.6% (14/103) among the patients from whom C. innocuum was isolated. The lowest concentrations at which 90% of the isolates were inhibited for metronidazole and vancomycin were 0.5 and 16 mg/L, respectively. All isolates tested were susceptible to metronidazole but resistant to vancomycin. Nineteen randomly selected isolates (ten from severe colitis group, nine from diarrhoea group) were subjected to further in vitro cellular examinations. The level of cytotoxicity to Vero cells was significantly higher in isolates from the severe colitis group at both 24 and 48 hours after inoculation (24 and 48 hours, p 0.042 and 0.033, respectively). We observed apoptotic changes that subsequently led to cell death in C. innocuum-infected Vero cells. Tissue damages, necrotic changes and oedema were observed in the mouse ileal loop infected by C. innocuum. CONCLUSIONS: Vancomycin-resistant C. innocuum may play a potential role as a causative agent of AAD. The clinical manifestations of AAD caused by C. innocuum were diarrhoea or severe colitis, including pseudomembranous colitis.


Subject(s)
Anti-Bacterial Agents/adverse effects , Clostridium Infections/microbiology , Clostridium/classification , Diarrhea/etiology , Vancomycin Resistance , Vancomycin/pharmacology , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Child , Child, Preschool , Clostridium/drug effects , Clostridium/pathogenicity , Clostridium Infections/pathology , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Risk Factors , Young Adult
3.
Oncogene ; 36(38): 5440, 2017 09 21.
Article in English | MEDLINE | ID: mdl-28714961

ABSTRACT

This corrects the article DOI: 10.1038/onc.2014.43.

4.
Sci Rep ; 7(1): 4715, 2017 07 05.
Article in English | MEDLINE | ID: mdl-28680089

ABSTRACT

A dramatic band gap narrowing of 1.61 eV has been observed in Co-doped nanocrystals of CeO2 (ceria), as a result of thermal annealing, without changing the ceria crystal structure and the Co concentration. As demonstrated by x-ray absorption fine structures, thermal annealing incurs an oxygen coordination rearrangement around Co atoms from an octahedral coordination to a square-planar coordination. First principle calculation using density functional theory reveals two stable oxygen coordination types surrounding Co, consistent with the experimental observation. The band gap values calculated for the two stable coordination types differ dramatically, reproducing the experimentally observed band gap narrowing. These prominent effects due to local structure rearrangement around dopant atoms can lead to unprecedented methods for band gap engineering in doped nanocrystal oxides.

5.
Sci Rep ; 5: 15415, 2015 Oct 21.
Article in English | MEDLINE | ID: mdl-26486721

ABSTRACT

We report the experimental observation and theoretical explanation of an unconventional interplay between divalent Co and trivalent Y dopants, both of which incur oxygen vacancies in the CeO2 host that has predominantly tetravalent Ce cations. The Co dopant atoms were experimentally found to act as a switch that turns on the dormant effect of Y-modulated band-gap reduction. As revealed by density functional theory (DFT) calculations with structures verified by synchrotron-radiation x-ray measurements, a Co 3d band that hybridizes with Ce 4f band was lowered due to reduced O 2p repulsion arising from oxygen vacancies incurred by Y doping and therefore gave rise to the observed band-gap narrowing effect. Such switch-and-modulator scheme for band-gap engineering in nanocrystal materials can lead to important applications in environmental protection and solar energy harvesting technologies.

6.
J Biol Regul Homeost Agents ; 29(2): 471-7, 2015.
Article in English | MEDLINE | ID: mdl-26122239

ABSTRACT

C-erbB-2 is a cancer gene originating from cells. The high-expression and amplification of C-erbB-2 and its protein products (P185) are found in a wide variety of tumors. The abnormal expression of C-erbB-2 has great influence on the occurrence and development of gastric carcinoma. This paper aimed to analyze the expression of C-erbB-2 in the tissues of gastric carcinoma, gastric mucosal atypical hyperplasia and gastritis, and discuss its role in the occurrence and development of gastric carcinoma. The morphological differences and connections among simple intestinal metaplasia (SIM), atypical intestinal metaplasia (AIM) and dysplasia in intestinal metaplasia through hematoxylin and eosin (HE) staining were studied. Three groups were set to detect the expression condition of C-erbB-2 by immunohistochemical method (IHC). The result showed that C-erbB-2 had no significant difference in AIM and gastric carcinoma, that is, AIM was closely related to gastric carcinoma. The positive expression was demonstrated of C-erbB-2 products (P185) in medium and gastric mucosa dysplasia tissues and was 29.41% and 66.67%, respectively, while it was 25%, 50% and 77.78% in high, medium and low differentiation of gastric carcinoma. It can be seen that there was a significant difference between them (P<0.05), and the expression degree was significantly enhanced (P<0.05); the expression degree in high differentiation gastric cancer tissue was significantly higher than the middle and low differentiation gastric cancer tissue. It was concluded that C-erbB-2 played an important role in the pathogenic mechanism of gastric carcinoma, and it might act on the later period of the gastric carcinoma, which provides objective reference index for the diagnosis and prognosis of gastric carcinoma and meanwhile provides instructional theoretical reference for the application of targeted drugs in the clinical treatment of gastric carcinoma.


Subject(s)
Carcinoma/chemistry , Gastric Mucosa/chemistry , Gastritis/metabolism , Neoplasm Proteins/analysis , Precancerous Conditions/metabolism , Receptor, ErbB-2/analysis , Stomach Neoplasms/chemistry , Carcinoma/pathology , Disease Progression , Gastric Mucosa/pathology , Gastritis/pathology , Gene Expression Regulation, Neoplastic , Genes, erbB-2 , Humans , Hyperplasia , Metaplasia , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Precancerous Conditions/pathology , Receptor, ErbB-2/biosynthesis , Stomach Neoplasms/pathology
7.
Br J Dermatol ; 173(5): 1224-31, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26218033

ABSTRACT

BACKGROUND: Malignancy is known to be associated with an increased mortality rate in patients with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, risk factors contributing to the poor prognosis of patients with SJS/TEN with malignancies remain undefined. OBJECTIVES: To explore the potential involvement of malignancy and its related factors contributing to the poor outcome of SJS/TEN, in a retrospective study. METHODS: In total 517 patients with SJS/TEN were enrolled. Forty-seven who sustained various types of malignancies were analysed for numerous malignancy-related factors, including cancer types, clinical stages and chemotherapies given or not before the onset of SJS/TEN. RESULTS: We found that the mortality rate of patients with SJS/TEN with malignancies was higher than that of patients without malignancies (32%, 15/47 vs. 8·5%, 40/470, respectively) (P < 0·001). The use of phenytoin was significantly higher in the malignancy group. The presence of hepatocellular carcinoma (80%, four of five; P < 0·001; odds ratio 43) and colorectal cancer (67%, two of three; P = 0·022; odds ratio 21·5) significantly increased the death rate of patients with SJS/TEN, whereas lung cancer and urothelial carcinoma did not. Patients who had received ongoing or recent chemotherapy showed higher mortality than those without chemotherapy (P = 0·022; odds ratio 4·95). Furthermore, among the 47 patients with SJS/TEN with malignancies, lower serum albumin, haemoglobin and platelet count were detected in the deceased patients than in the surviving patients before the onset of SJS/TEN. CONCLUSIONS: Our results suggest that several factors related to malignancies, such as specific cancer types, chemotherapy and malnutrition, may contribute to poor prognosis in patients with malignancies developing SJS/TEN.


Subject(s)
Neoplasms/mortality , Stevens-Johnson Syndrome/mortality , Anti-Bacterial Agents/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anticonvulsants/adverse effects , Antineoplastic Agents/adverse effects , Female , Humans , Male , Middle Aged , Neoplasms/complications , Neoplasms/drug therapy , Prognosis , Retrospective Studies , Risk Factors , Sepsis/mortality , Stevens-Johnson Syndrome/complications , Taiwan/epidemiology
8.
J Clin Pharm Ther ; 40(4): 368-75, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25893507

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Proton pump inhibitors (PPIs) are one of the most widely used classes of drugs. However, the quantum clinical benefit of newer and more expensive PPIs over the older generation PPIs remains uncertain. This meta-analysis sought to assess the clinical and safety profiles of esomeprazole versus omeprazole at pharmacologically equivalent doses in healing gastroesophageal reflux disease (GERD), peptic ulcer disease and eradicating Helicobacter pylori (H. pylori) infection. METHODS: PubMed and the Cochrane Library were searched for randomized controlled trials comparing esomeprazole with omeprazole at all doses up to February 2015. Trials were assessed by two reviewers for eligibility according to predefined study inclusion criteria. Meta-analysis was conducted using a random effects model, and heterogeneity in the estimated effects was investigated using meta-regression. Sensitivity analysis was performed to test the robustness of the findings. RESULTS AND DISCUSSION: Fifteen trials were included and none of which compared esomeprazole with omeprazole in peptic ulcer disease. The included studies had not evaluated esomeprazole 20 mg versus omeprazole 40 mg. In GERD, esomeprazole 40 mg (relative risk (RR) = 1·07; 95% confidence interval (CI) 1·02 to 1·12) and 20 mg (RR=1·04; 95% CI 1·01 to 1·08) significantly improved esophagitis healing when compared with omeprazole 20 mg at week 8. The corresponding numbers needed to treat were 17 and 30, respectively. No significant difference was observed between esomeprazole 20 mg and omeprazole 20 mg at week 4. In H. pylori eradication, there was no difference in the treatment effects between esomeprazole 20 mg and omeprazole 20 mg (RR = 1·01;95% CI 0·96 to 1·05). Their safety profiles were comparable. WHAT IS NEW AND CONCLUSION: Esomeprazole demonstrated better esophagitis healing rate in patients with GERD than omeprazole at week 8. However, this clinical advantage diminished when both drugs were given at the same doses at week 4. Superiority of esomeprazole was not observed in the H. pylori eradication rates.


Subject(s)
Esomeprazole/therapeutic use , Gastroesophageal Reflux/drug therapy , Helicobacter Infections/drug therapy , Esomeprazole/adverse effects , Esomeprazole/pharmacology , Gastroesophageal Reflux/microbiology , Helicobacter Infections/microbiology , Helicobacter pylori/isolation & purification , Humans , Omeprazole/adverse effects , Omeprazole/therapeutic use , Proton Pump Inhibitors/adverse effects , Proton Pump Inhibitors/pharmacology , Proton Pump Inhibitors/therapeutic use , Randomized Controlled Trials as Topic
9.
Oncogene ; 34(10): 1207-19, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-24681956

ABSTRACT

B-cell lymphoma/leukemia 10 (BCL10) is an apoptotic regulatory protein related to advanced TNM stage and disease recurrence in oral squamous cell carcinoma (OSCC). However, the regulatory mechanism of BCL10 in OSCC progression is still unknown. Here, we showed that knockdown of endogenous BCL10 could significantly reduce cell migration and invasion abilities, retard cell proliferation by G0/G1 phase accumulation and inhibit tumorigenicity in vivo. In molecular level, we identified S100P as a crucial downstream effector of BCL10-inhibited OSCC progression by high-throughput microarray analysis. S100P messenger RNA and protein expression levels were significantly diminished in silenced-BCL10 clones, and transfected S100P expression plasmids restored migration, invasion, proliferation abilities and tumorigenicity in shBCL10 transfectants. Furthermore, we provided evidence that BCL10 regulated S100P expression through signal transducers and activators of transcription 1 (STAT1) and activating transcription factor 4 (ATF4). Knockdown of BCL10 decreased S100P promoter activity, but showed no effect in truncated STAT1/ATF4 S100P promoter.  In addition, we also found that the P50/P65 signaling pathway was involved in BCL10-enhanced OSCC progression. Restored S100P in silenced-BCL10 clones could markedly reverse P65 activation via outside-in signaling. Taken together, we discovered a novel axis of BCL10-regulated OSCC progression via STAT1/ATF4/S100P/P65 signaling, which could predict the prognosis of OSCC and will be beneficial for developing therapeutic strategy against advanced OSCC.


Subject(s)
Activating Transcription Factor 4/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Calcium-Binding Proteins/metabolism , Mouth Neoplasms/metabolism , Neoplasm Proteins/metabolism , STAT1 Transcription Factor/metabolism , Signal Transduction , Activating Transcription Factor 4/genetics , Adaptor Proteins, Signal Transducing/genetics , Animals , B-Cell CLL-Lymphoma 10 Protein , Binding Sites , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Disease Models, Animal , Disease Progression , Gene Knockdown Techniques , Heterografts , Humans , Mice , Mouth Neoplasms/genetics , Mouth Neoplasms/mortality , Mouth Neoplasms/pathology , Prognosis , Protein Binding , Transcriptional Activation
10.
Eur J Clin Microbiol Infect Dis ; 31(4): 583-90, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21845470

ABSTRACT

We evaluated the impact of a prospective audit and feedback antimicrobial stewardship program (ASP) on antibiotic prescription and resistance trends in a hematology-oncology unit in a university hospital (National University Cancer Institute, Singapore [NCIS]). A prospective interrupted time-series study comprising 11-month pre-intervention (PIP) and intervention evaluation phases (IEP) flanking a one-month implementation phase was carried out. Outcome measures included defined daily dose per 100 (DDD/100) inpatient-days of ASP-audited and all antibiotics (encompassing audited and non-audited antibiotics), and the incidence-density of antibiotic-resistant microorganisms at the NCIS. Internal and external controls were DDD/100 inpatient-days of paracetamol at the NCIS and DDD/100 inpatient-days of antibiotics prescribed in the rest of the hospital. There were 580 ASP recommendations from 1,276 audits, with a mean monthly compliance of 86.9%. Significant reversal of prescription trends towards reduced prescription of audited (coefficient = -2.621; 95% confidence interval [CI]: -4.923, -0.319; p = 0.026) and all evaluated antibiotics (coefficient = -4.069; 95% CI: -8.075, -0.063; p = 0.046) was observed. No changes were seen for both internal and external controls, except for the reversal of prescription trends for cephalosporins hospital-wide. Antimicrobial resistance did not change over the time period of the study. Adverse outcomes-the majority unavoidable-occurred following 5.5% of accepted ASP recommendations. Safe and effective ASPs can be implemented in the complex setting of hematology-oncology inpatients.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Drug Prescriptions/statistics & numerical data , Fever of Unknown Origin/drug therapy , Adult , Bacteria/drug effects , Bacteria/isolation & purification , Drug Resistance, Bacterial , Drug Utilization/statistics & numerical data , Hematologic Neoplasms/complications , Humans , Medical Audit , Prospective Studies , Singapore
12.
Br J Pharmacol ; 153(1): 110-23, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17965733

ABSTRACT

BACKGROUND AND PURPOSE: Cinnamophilin, a thromboxane A(2) receptor antagonist, has been identified as a prominent anti-arrhythmic agent in rat heart. This study aimed to determine its electromechanical and anti-arrhythmic effects in guinea-pig hearts. EXPERIMENTAL APPROACH: Microelectrodes were used to study action potentials in ventricular papillary muscles. Fluo-3 fluorimetric ratio and whole-cell voltage-clamp techniques were used to record calcium transients and membrane currents in single ventricular myocytes, respectively. Intracardiac electrocardiograms were obtained and the anti-arrhythmic efficacy was determined from isolated perfused hearts. KEY RESULTS: In papillary muscles, cinnamophilin decreased the maximal rate of upstroke (V(max)) and duration of action potential, and reduced the contractile force. In single ventricular myocytes, cinnamophilin reduced Ca(2+) transient amplitude. Cinnamophilin decreased the L-type Ca(2+) current (I(Ca,L))(IC(50)=7.5 microM) with use-dependency, induced a negative shift of the voltage-dependent inactivation and retarded recovery from inactivation. Cinnamophilin also decreased the Na(+) current (I(Na)) (IC(50)=2.7 microM) and to a lesser extent, the delayed outward (I(K)), inward rectifier (I(K1)), and ATP-sensitive (I(K,ATP)) K(+) currents. In isolated perfused hearts, cinnamophilin prolonged the AV nodal conduction interval and Wenckebach cycle length and the refractory periods of the AV node, His-Purkinje system and ventricle, while shortening the ventricular repolarization time. Additionally, cinnamophilin reduced the occurrence of reperfusion-induced ventricular fibrillation. CONCLUSIONS AND IMPLICATIONS: These results suggest that the promising anti-arrhythmic effect and the changes in the electromechanical function induced by cinnamophilin in guinea-pig heart can be chiefly accounted for by inhibition of I(Ca,L) and I(Na).


Subject(s)
Anti-Arrhythmia Agents/pharmacology , Guaiacol/analogs & derivatives , Heart/drug effects , Lignans/pharmacology , Receptors, Thromboxane A2, Prostaglandin H2/antagonists & inhibitors , Animals , Calcium Channels, L-Type/drug effects , Calcium Channels, L-Type/physiology , Guaiacol/pharmacology , Guinea Pigs , Heart Conduction System/drug effects , Heart Conduction System/physiology , In Vitro Techniques , Male , Papillary Muscles/drug effects , Papillary Muscles/physiology , Potassium Channels/drug effects , Potassium Channels/physiology , Sodium Channels/drug effects , Sodium Channels/physiology
13.
Br J Dermatol ; 157(3): 587-90, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17596145

ABSTRACT

Background The potentially fatal complications associated with viral hepatitis B (HBV) reactivation have not been characterized in bullous/connective tissue disease patients receiving prolonged systemic glucocorticosteroids (GCs). Objectives This study reports HBV reactivation following GC therapy for a case series of pemphigus vulgaris and dermatomyositis. Methods The retrospective study cohort comprised 98 patients who received at least 6 months of systemic GC therapy. Results Four cases of HBV carriers with viral hepatitis flare were identified. Two patients suffered fulminant hepatitis and died, while the remaining two patients experienced recurrent hepatitis flare following antiviral medication. The mean time from the start of GCs to the time of HBV reactivation was 10.5 months. Conclusions HBV infection is an important global public health problem. Fatal HBV reactivation may occur following long-term systemic GC therapy. Given the risk of mortality, all bullous/connective tissue disease patients should be screened for serum hepatitis B markers before commencing systemic GC therapy.


Subject(s)
Dermatomyositis/virology , Glucocorticoids/adverse effects , Hepatitis B virus/drug effects , Hepatitis B, Chronic/virology , Pemphigus/virology , Virus Activation , Adult , Aged , Cohort Studies , Fatal Outcome , Female , Glucocorticoids/administration & dosage , Hepatitis B Surface Antigens/blood , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
14.
J Nat Prod ; 64(11): 1404-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11720521

ABSTRACT

Four new pavine alkaloids, (+)-eschscholtzidine-N-oxide (1), (-)-12-hydroxycrychine (2), (-)-12-hydroxy-O-methylcaryachine (3), and (-)-N-demethylcrychine (4), and four new proaporphine alkaloids, isocryprochine (5), prooxocryptochine (6), isoamuronine (7), and (+)-8,9-dihydrostepharine (8), together with nine known compounds were isolated from an ethanol extract of the wood of Cryptocarya chinensis. Their structures were elucidated by spectral analysis (NMR and MS), and the structures of 2 and 5 were confirmed by X-ray crystallography.


Subject(s)
Alkaloids/isolation & purification , Drugs, Chinese Herbal/isolation & purification , Lauraceae/chemistry , Alkaloids/chemistry , Crystallography, X-Ray , Drugs, Chinese Herbal/chemistry , Mass Spectrometry , Medicine, Chinese Traditional , Molecular Conformation , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plants, Medicinal/chemistry , Spectroscopy, Fourier Transform Infrared , Taiwan , Wood
15.
Chem Pharm Bull (Tokyo) ; 49(10): 1292-4, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11605656

ABSTRACT

Investigation of the leaves of Cryptocarya chinensis resulted in the isolation of three new alkaloids, named (-)-isocaryachine-N-oxide, isoboldine-beta-N-oxide, and 1-hydroxycryprochine, together with seven known compounds. Their structures were elucidated by spectral analysis. The structures of (-)-isocaryachine-N-oxide and 1-hydroxycryprochine were further confirmed by X-ray techniques.


Subject(s)
Alkaloids/chemistry , Benzylisoquinolines , Dioxoles/chemistry , Lauraceae/chemistry , Alkaloids/isolation & purification , Crystallography, X-Ray , Dioxoles/isolation & purification , Magnetic Resonance Spectroscopy , Models, Molecular , Plant Leaves/chemistry , Spectrometry, Mass, Fast Atom Bombardment , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet
16.
J Nat Prod ; 64(8): 1040-3, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11520222

ABSTRACT

Two new tetranortriterpenoids, 7-isovaleroylcycloseverinolide (1) and 7-isovaleroylcycloepiatalantin (2), together with 28 known compounds, were isolated and characterized from the root bark of Severinia buxifolia collected in Hainan. The structures of 1 and 2 were elucidated on the basis of spectral evidence including 2D NMR and X-ray techniques. The cytotoxicity of several acridone alkaloid isolates (3-8) was evaluated against a small tumor cell panel.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Drugs, Chinese Herbal/isolation & purification , Plants, Medicinal/chemistry , Triterpenes/isolation & purification , Acridines/chemistry , Acridines/pharmacology , Acridones , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Carcinoma, Hepatocellular , Colonic Neoplasms , Crystallography, X-Ray , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Humans , KB Cells , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Roots/chemistry , Taiwan , Triterpenes/chemistry , Triterpenes/pharmacology , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism
17.
J Nat Prod ; 64(8): 1121-2, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11520245

ABSTRACT

Two new triterpenoids, lucidenic acid N (1) and methyl lucidenate F (2), together with four known compounds, lucidenic acid A, lucidenolactone, lucidenic acid C, and ganoderic acid E, were isolated from the dried fruiting bodies of Ganoderma lucidum. Their structures were elucidated by spectral and chemical transformation studies. Among them, lucidenic acid N (1), lucidenic acid A, and ganoderic acid E showed significant cytotoxic activity against Hep G2, Hep G2,2,15, and P-388 tumor cells.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Drugs, Chinese Herbal/isolation & purification , Polyporaceae/chemistry , Triterpenes/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Humans , KB Cells/drug effects , Magnetic Resonance Spectroscopy , Molecular Structure , Spectrophotometry, Ultraviolet , Triterpenes/chemistry , Triterpenes/pharmacology , Tumor Cells, Cultured/drug effects
19.
Biochim Biophys Acta ; 1525(1-2): 77-88, 2001 Feb 16.
Article in English | MEDLINE | ID: mdl-11342256

ABSTRACT

The antioxidant properties of cinnamophilin were evaluated by studying its ability to react with relevant reactive oxygen species, and its protective effect on cultured cells and biomacromolecules under oxidative stress. Cinnamophilin concentration-dependently suppressed non-enzymatic iron-induced lipid peroxidation in rat brain homogenates with an IC50 value of 8.0+/-0.7 microM and iron ion/ADP/ascorbate-initiated rat liver mitochondrial lipid peroxidation with an IC50 value of 17.7+/-0.2 microM. It also exerted an inhibitory activity on NADPH-dependent microsomal lipid peroxidation with an IC50 value of 3.4+/-0.1 microM without affecting microsomal electron transport of NADPH-cytochrome P-450 reductase. Both 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azo-bis(2-amidinopropane) dihydrochloride-derived peroxyl radical tests demonstrated that cinnamophilin possessed marked free radical scavenging capacity. Cinnamophilin significantly protected cultured rat aortic smooth muscle cells (A7r5) against alloxan/iron ion/H2O2-induced damage resulting in cytoplasmic membranous disturbance and mitochondrial potential decay. By the way, cinnamophilin inhibited copper-catalyzed oxidation of human low-density lipoprotein, as measured by fluorescence intensity and thiobarbituric acid-reactive substance formation in a concentration-dependent manner. On the other hand, it was reactive toward superoxide anions generated by the xanthine/xanthine oxidase system and the aortic segment from aged spontaneously hypertensive rat. Furthermore, cinnamophilin exerted a divergent effect on the respiratory burst of human neutrophil by different stimulators. Our results show that cinnamophilin acts as a novel antioxidant and cytoprotectant against oxidative damage.


Subject(s)
Cryoprotective Agents/pharmacology , Free Radical Scavengers/pharmacology , Guaiacol/analogs & derivatives , Guaiacol/pharmacology , Lignans/pharmacology , Lipid Peroxidation/drug effects , Animals , Aorta/drug effects , Aorta/metabolism , Brain/drug effects , Brain/metabolism , Cell Line , Cell Membrane/drug effects , Cell Membrane/metabolism , Humans , In Vitro Techniques , Liver/drug effects , Liver/metabolism , Mitochondria, Liver/drug effects , Mitochondria, Liver/metabolism , NADPH Oxidases/metabolism , NADPH-Ferrihemoprotein Reductase/metabolism , Neutrophils/drug effects , Neutrophils/metabolism , Peroxides/metabolism , Rats , Rats, Inbred SHR , Rats, Wistar , Superoxides/metabolism
20.
Bioorg Med Chem ; 9(1): 77-83, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11197349

ABSTRACT

Five new constituents including a flavonoid, artemisidin A (1), and four coumarins, artemicapins A (2), B (3), C (4) and D (5), together with 70 known compounds (6-75), have been isolated and characterized from the aerial part of Artemisia capillaris. The structures of these compounds were determined from spectral analyses and/or chemical evidence. Among them, 15 compounds (3, 6, 10, 18. 30-32, 38-41, 44, 45, 51, and 55) showed antiplatelet aggregation activity and three compounds (10, 17, and 51) demonstrated significant activity against HIV replication in H9 lymphocytic cells.


Subject(s)
Acetylene/analogs & derivatives , Anti-HIV Agents/isolation & purification , Artemisia/chemistry , Plants, Medicinal , Platelet Aggregation Inhibitors/isolation & purification , Acetylene/pharmacology , Animals , Blood Platelets/drug effects , Caffeic Acids/pharmacology , Coumarins/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Platelet Aggregation Inhibitors/pharmacology , Rabbits , Spectrophotometry
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