The analysis of DNA microarry data is one of the most important things for functional genomics research. The matrix representation of microarray data and its successive 'optimal' incisional hyperplanes is a useful platform for developing optimization algorithms to determine the optimal partitioning of pairwise proximity matrix representing completely connected and weighted graph. We developed Deterministic Annealing (DA) approach to determine the successive optimal binary partitioning. DA algorithm demonstrated good performance with the ability to find the 'globally optimal' binary partitions. In addition, the objects that have not been clustered at small non-zero temperature, are considered to be very sensitive to even small randomness, and can be used to estimate the reliability of the clustering.
Cluster Analysis ; DNA* ; Gene Expression* ; Genomics ; Oligonucleotide Array Sequence Analysis*

Clostridium difficile infection (CDI) has become a significant threat to public health. Although broad-spectrum antibiotic therapy is the primary treatment option for CDI, its use has evident limitations. Probiotics have been proved to be effective in the treatment of CDI and are a promising therapeutic option for CDI. In this study, 4 strains of lactic acid bacteria (LAB), namely, Lactobacillus rhamnosus (LR5), Lactococ-cuslactis (SL3), Bifidobacterium breve (BR3), and Bifidobacterium lactis (BL3) were evaluated for their anti-C. difficile activity. Co-culture incubation of C. difficile (106 and 1010 CFU/ml) with each strain of LAB indicated that SL3 possessed the highest antimicrobial activity over a 24-hr period. The cell-free supernatants of the 4 LAB strains exhibited MIC50 values between 0.424 mg/ml (SL3) and 1.318 (BR3) mg/ml. These results may provide a basis for alternative therapies for the treatment of C. difficile-associated gut disorders.
Bacteria ; Bifidobacterium ; Clostridium ; Clostridium difficile ; Coculture Techniques ; Complementary Therapies ; Lactic Acid ; Lactobacillus rhamnosus ; Probiotics ; Public Health ; Pyridines ; Sprains and Strains ; Thiazoles

OBJECTIVETo establish the HPLC chromatographic fingerprint of Kumu injection and to simultaneously determine the contents of three beta-carboline alkaloids, comprehensively evaluating the immanent quality of Kumu injection.

METHODThe chromatographic analysis was performed on a Phenomenex Gemini C18 ( 4.6 mm x 250 mm, 5 microm) column with the gradient elution solvent system composed of methanol and 30 mmol x L(-1) aqueous ammonium acetate (adjusted with glacial acetic acid to pH 4.5). Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004 A) was used in data analysis.

RESULTSixteen co-possessing peaks were selected as the fingerprints of Kumu injection, and 7 peaks were identified by chemical reference substances. There were good similarities between the standard fingerprint chromatogram and each fingerprint chromatogram from the eleven samples for their similarity coefficients were not less than 0.9. Three kinds of beta-carboline alkaloids were separated well. The correlation coefficients were 0.999 9. The linear ranges of three components were 0.020 0-0.300 0, 0.102 0-1.530 0, 0.015 2-0. 228 0 microg, respectively, and the average recoveries ranged were from 99.5% to 102%.

CONCLUSIONThe method of fingerprint combined with quantitative analysis is sensitive, selective, and provide scientific basis for quality control of Kumu Injection.

Alkaloids ; analysis ; Carbolines ; analysis ; Chromatography, High Pressure Liquid ; methods ; Drug Stability ; Drugs, Chinese Herbal ; chemistry ; Injections ; Pharmaceutical Solutions ; Picrasma ; chemistry ; Plants, Medicinal ; chemistry ; Quality Control ; Reproducibility of Results ; Sensitivity and Specificity

The effect of carbon tetrachloride (CCl4) on aflatoxin B1 (AFB1)-induced enzyme altered hepatic foci has been examined in young male Fischer rats given AIN-76A diet. A single i.p. dose of AFB1 (0.2 mg/kg body wt) was given to rats 24 h after partial hepatectomy. Two weeks later, CCl4 (0.8 ml/kg body wt) was injected i.p. once a week for 9 weeks. Animals were sacrificed 24 h after the last dose of CCl4 and glutathione S-transferase placental form (GST-P) and gamma-glutamyl transpeptidase (GGT) positive hepatic foci were analyzed by immunohistochemical and histochemical methods, respectively. Ten weeks after AFB1 dosing, treatment with CCl4 increased the number of AFB1-induced enzyme altered foci several fold and produced a ten to twenty-fold increase in area and volume. GST-P was more sensitive than GGT in detecting AFB1-induced enzyme altered foci. Treatment with AFB1 or CCl4 produced mild hepatic fibrosis in zones 1 and 3 respectively, whereas both treatments produced severe fibrosis in zones 1 to 3 areas. Treatment with CCl4 after AFB1 dosing lowered hepatic GSH levels by 20% and increased lipid peroxidation by 40%. It appears that CCl4, by being an effective enhancer of AFB1-induced enzyme altered hepatic foci in the rat, may mimic cirrhosis observed in human hepatocellular carcinoma.
Aflatoxin B1/pharmacology* ; Animal ; Carbon Tetrachloride/pharmacology* ; Drug Synergism ; Fibrosis/chemically induced ; Glutathione Transferase/metabolism* ; Immunohistochemistry ; Lipid Peroxidation/drug effects ; Liver Neoplasms, Experimental/chemically induced* ; Male ; Rats ; gamma-Glutamyltransferase/metabolism*

No abstract available.
Adult* ; Humans ; Technetium Tc 99m Dimercaptosuccinic Acid* ; Tomography, Emission-Computed, Single-Photon* ; Urinary Tract Infections* ; Urinary Tract*

Deep brain stimulation (DBS) surgery has been performed in over 75,000 people worldwide, and has been shown to be an effective treatment for Parkinson's disease, tremor, dystonia, epilepsy, depression, Tourette's syndrome, and obsessive compulsive disorder. We review current and emerging evidence for the role of DBS in the management of a range of neurological and psychiatric conditions, and discuss the technical and practical aspects of performing DBS surgery. In the future, evolution of DBS technology may depend on several key areas, including better scientific understanding of its underlying mechanism of action, advances in high-spatial resolution imaging and development of novel electrophysiological and neurotransmitter microsensor systems. Such developments could form the basis of an intelligent closed-loop DBS system with feedback-guided neuromodulation to optimize both electrode placement and therapeutic efficacy.
Brain ; Deep Brain Stimulation ; Depression ; Dystonia ; Electrodes ; Epilepsy ; Neurotransmitter Agents ; Obsessive-Compulsive Disorder ; Parkinson Disease ; Tourette Syndrome ; Tremor

Deep brain stimulation (DBS) surgery has been performed in over 75,000 people worldwide, and has been shown to be an effective treatment for Parkinson's disease, tremor, dystonia, epilepsy, depression, Tourette's syndrome, and obsessive compulsive disorder. We review current and emerging evidence for the role of DBS in the management of a range of neurological and psychiatric conditions, and discuss the technical and practical aspects of performing DBS surgery. In the future, evolution of DBS technology may depend on several key areas, including better scientific understanding of its underlying mechanism of action, advances in high-spatial resolution imaging and development of novel electrophysiological and neurotransmitter microsensor systems. Such developments could form the basis of an intelligent closed-loop DBS system with feedback-guided neuromodulation to optimize both electrode placement and therapeutic efficacy.
Brain ; Deep Brain Stimulation ; Depression ; Dystonia ; Electrodes ; Epilepsy ; Neurotransmitter Agents ; Obsessive-Compulsive Disorder ; Parkinson Disease ; Tourette Syndrome ; Tremor

Aim: To research the neuroprotective effect of ticagrelor against global cerebral ischemia/reperfusion injury in rats. Methods: Fifty adult male Wistar rats were randomly divided into five groups; sham-operation, vehicle, ticagrelor of 3 doses (37.5, 75, 150 mg · kg-1, ig). The global cerebral ischemia was established with four-vessel occlusion. Apoplexy index and neurological symptoms were detected after reperfusion injury 2 h, 24 h, 48 h. HE staining and Nissl staining were applied to assess the neuronal injury after global cerebral ischemia/reperfusion injury in CA1 region of hippocampus. Platelet aggregation induced by ADP in rats was measured with turbidimetric method. Four items of coagulation were detected by automatic coagulation analyzer. Results: Compared with vehicle, the low, medium and high doses of ticagrelor reduced the apoplexy index at 24h (P <0. 05), 48 h(P < 0. 01), and significantly reduced the neurological symptom at 48 h (P < 0. 01), and could significantly reduce platelet aggregation of rats (P < 0. 01), the number of neurons in CA1 region of hippocampus was larger (P < 0. 01), and it also significantly protected the neurons in both number and morphology. Conclusions: The ticagrelor possesses neuroprotective effect against global cerebral ischemia/reperfusion injury in rats, and it may be as a drug of neuroprotective agent in further study.

PURPOSE: Faculty development (FD) is essential to prepare faculty members to become effective teachers to meet the challenges in medical education. Despite the growth of FD programmes, most evaluations were often conducted using short questionnaires to assess participants’ satisfaction immediately after they attended a programme. Consequently, there were calls for more rigorous evaluations based on observed changes in participants’ behaviours. Hence, this study aims to explore how the FD workshops run by the Centre for Medical Education, Yong Loo Lin School of Medicine, National University of Singapore have impacted behavioural changes in the educators. METHODS: We followed up with the educators at least half a year after they have attended the workshops. With limited literature as reference, we initiated a small-scale case-study research design involving semi-structured interviews with six educators which was triangulated with three focus group discussions with their students. This allowed us to explore behavioural changes among the educators as well as evaluate the feasibility of this research methodology. RESULTS: We identified three emerging categories among the educators: ignorance to awareness, from intuition to confirmation and expansion, and from individualism to community of practice. CONCLUSION: Although FD have placed much emphasis on teaching and learning approaches, we found that the teacher-student interaction or human character components (passionate, willing to sacrifice, are open to feedback) in becoming a good educator are lacking in our FD workshops.
Education ; Education, Medical ; Focus Groups ; Humans ; Intuition ; Learning ; Research Design ; Singapore

Purpose: The use of mobile devices among medical students and residents to access online material in real-time has become more prevalent. Most literature focused on the technical/functional aspects of mobile use. This study, on the other hands, explored students, doctors and patients’ preferences and reasons towards the use of mobile devices in clinical settings underpinned by the Technology Acceptance Model 2 (TAM 2). Methods: This research employs an exploratory research design using survey and semi-structured interviews. An online survey was administered to clinical year medical students, followed by semi-structured interviews with the doctors and patients. Questions for the online survey and semi-structured interviews were derived from previous literature and was then reviewed by authors and an expert panel. A convenience sampling was used to invite voluntary participants. Results: Survey findings showed that most medical students used their devices to find drug information and practice guidelines. The majority of the students accessed UpToDate followed by Google to access medical resources. Key barriers that students often encountered during the use of mobile devices were internet connectivity in the clinical settings, reliability of the information, and technical issues. Thematic analysis of the interviews revealed four themes: general usage by students, receptivity of the use of mobile devices by students, features in selecting resources for mobile learning, and limitation in the current use of mobile devices for learning. Conclusion The findings from this study assist in recommending suitable material using mobile devices to enhance learning in the clinical environment and expand the TAM 2.