AIM: To evaluate the antioxidant activity of naringenin in human retinal pigment epithelium (ARPE-19) cells andhuman umbilical vein endothelial cells (HUVEC).·METHODS: MTT assay was used to measure theviability and proliferation of ARPE-19 cells and HUVEC.·RESULTS: Three and 10mg/L naringenin significantlyincreased the proliferation of ARPE-19 cells by 10.8% and11.4%, respectively. Ten mg/L naringenin increasedhypoxia-, 0.3mmol/L NAN3-, and 200μmol/L H2O2- induced damage of ARPE-19 cells by 55.2%, 69.2%, and50.3%, respectively. One mg/L naringenin increased theviability of 50μmol/L t-BHP-, and 30mg/L NalO3-treatedARPE-19 cells by 20.2% and 30.4%, respectively. Thirtymg/L naringenin also increased the proliferation of50μmol/L t-BHP-treated ARPE-19 cells by 32.2%, and1mg/L naringenin increased the proliferation of 30, 100and 300 mg/L NalO3-treated ARPE-19 cells by 30.3%,10.3% and 18.5%, respectively. The reduction of HUVECwas 23.9%, 70.4% and 77.9% in the 3, 10 and 30mg/Lnaringenin-treated groups, respectively. Furthermore, 1and 3mg/L naringenin increased hypoxia-induced damagein HUVEC by 10.7% and 13.1%, and 300mg/L NalO3- induced damage in HUVEC by 41.2% and 37.7%. Threemg/L naringenin increased 200 and 400μmol/L H2O2-in-jured HUVEC by 20.1% and 21.5%, respectively.·CONCLUSION: Naringenin increases the proliferation ofARPE-19 cells and inhibites the growth of HUVEC, and haspotent antioxidant activity in ARPE-19 cells and HUVEC.

This article is to provide a general overview of cancer in China including the statistics, most common cancers, their epidemiological characteristics and the treatments.

AIM: To study the effects of Tetramethylpyrazine (TMP) on retinal pigment epithelium (RPE) degeneration, choroidal blood flow and oxidative stress of RPE cells.METHODS: The 35mg/kg NaIO3-induced RPE degeneration rat eyes was given 25μg 1% TMP eye drops 3 times a day for 7 days before NaIO3 injection, and then 2 to 4 weeks after NaIO3 injection. RPE function was measured with c-wave of electroretinogram (ERG). Colored microsphere technique was used for in vivo experiments to determine the choroidal blood flow in ocular hypertensive (40mmHg) rabbit eyes. Methylthiazoltetrazolium (MTT) assay was used to study in vitro effect of TMP on various oxidants induced injury in the hRPE (ARPE-19 (ATCC, Manassas, VA, USA)) . RESULTS: Two weeks after NaIO3 injection, the amplitude of ERG c-wave fell markedly in NaIO3 group to 36% of control group (P<0.01). No apparent difference was observed in TMP+NaIO3 group. Four weeks later, the NaIO3 group fell to 46% of control group (P<0.01), while the TMP+NaIO3 group fell to only 77% of control group (P<0.01). There was a 67% reversal of the ERG c-wave by TMP as compared to NaIO3 group (P<0.01). The choroidal blood flow was significantly increased at all time points (at 30, 60 and 120 minutes after TMP instillation) as compared with corresponding controls. TMP had no effect on hypoxia-(1%O2), t-BHP- and H2O2-induced damage in RPE cells. 10μg/mL TMP could reverse 1 and 3mmol/L NaN3-induced loss of viability of RPE by 18.5% (P<0.01) and 23% (P<0.01), respectively. 30μg/mL TMP could reverse 30 and 100mmol/L NaIO3 induced loss of viability of RPE by 18.1% (P<0.05) and 16.8% (P<0.01), respectively.CONCLUSION: TMP can significantly protect RPE from NaIO3 induced degeneration in vivo and oxidative stress in vitro and can increase choroidal blood flow markedly in vivo .

Porphyromonas gingivalis (P. gingivalis) has a strong association with the pathogenesis of periodontal disease. Recurrence of periodontal disease following therapy is attributed to numerous factors, and of growing interest is the potential problem of intracellular bacteria that are able to persist and multiply within the host cell, thereby facilitating relapse of infection. The effect of antibiotic therapy in controlling P. gingivalis is questionable. Accordingly, while metronidazole is very effective against anaerobic extracellular P. gingivalis by disrupting the DNA of anaerobic microbial cells, this antibiotic does not effectively penetrate into mammalian cells to inhibit intracellular bacteria. Therefore in the present study, a modified porphyrin-linked metronidazole adducts, developed in our laboratory, was used to kill intracellular P. gingivalis. A series of experiments were performed, including cytotoxicity assays and cellular uptake of adducts by flow cytometry coupled with live cell imaging analysis, P. gingivalis invasion and elimination assays, and the analysis of colocalization of P. gingivalis and porphyrin-linked metronidazole by confocal laser scanning microscopy. Findings indicated that P. gingivalis and porphyrin-linked metronidazole were colocalized in the cytoplasm, and this compound was able to kill P. gingivalis intracellular with a sufficient culture time.This is a novel antimicrobial approach in the elimination of P. gingivalis from the oral cavity.

INTRODUCTIONSingaporeans are superstitious, and medical staff are no exception to the rule. We conducted a survey to determine the prevalence of superstitious beliefs and practices amongst doctors, nurses and medical students in Singapore.

METHODSInternet and face-to-face surveys of 68 respondents, all of whom completed the survey after being threatened with curses and hexes.

RESULTSSixty-eight doctors, nurses and medical students responded to our survey. Only 11 admitted to being superstitious, yet 31 believed in the ill-fortune associated with eating bao or meat dumplings, 6 in the nefarious powers of black (5) or red (1) outfits on call, and 14 believed that bathing (6 insisting on the powers of the seven-flower bath) prior to the onset of a call portended good fortune, in terms of busy-ness of a call. Twenty-four believed in "black clouds", i.e. people who attracted bad luck whilst on call, and 32 refused to mouth the words "having a good call" until the day after the event. We discovered 2 hitherto undescribed and undiscovered superstitions, namely the benefits of eating bread and the need to avoid beef, for the good and ill fortune associated with their ingestion.

DISCUSSIONSuperstitious practices are alive and well in modern-day Singapore, the practice not necessarily being restricted to the poorly-educated or foolish.

Attitude of Health Personnel ; Humans ; Singapore ; Superstitions

Escalating healthcare costs in Singapore have produced a significant movement of patients into ambulatory care, and the consequent dearth of clinical teaching materials. This deficiency has likewise prompted the creation of ambulatory teaching clinics and the use of standardised patients and simulators. In the last few decades, educators have utilised digital technology, for instance, digitally recorded heart and breath sounds, and digitised video vignettes, in medical education. We describe several pedagogical initiatives that we have undertaken at our university school of medicine.
Ambulatory Care ; Curriculum ; Diffusion of Innovation ; Education, Medical ; methods ; Humans ; Medical Informatics ; trends ; Singapore ; User-Computer Interface

INTRODUCTIONMotor neuron damage and cortical spinal tract (CST) degeneration in amyotrophic lateral sclerosis (ALS) are difficult to visualise and quantify on conventional magnetic resonance imaging (MRI).

CLINICAL PICTUREWe studied 8 ALS patients and 12 normal volunteers using diffusion tensor imaging (DTI) and fibre tractography using fibre assignment by continuous tracking (FACT) to study the fibres of the CST and the posterior thalamic radiation (PTR), a nonmotor tract.

OUTCOMEFibre tractography was successfully performed in all normal volunteers and all patients except 1. The fibre bundles of the CST, but not the PTR, were significantly reduced (P <0.05) in patients compared to normal volunteers.

CONCLUSIONFibre tractography can visualise axonal degeneration in the CST and may provide supplementary information about upper motor neuron disease in ALS patients.

Amyotrophic Lateral Sclerosis ; pathology ; Case-Control Studies ; Diffusion Magnetic Resonance Imaging ; Echo-Planar Imaging ; Female ; Humans ; Male ; Middle Aged ; Nerve Degeneration ; pathology ; Pyramidal Tracts ; pathology

This review addresses the importance of psychoneuroimmunology (PNI) studies in understanding the role of acute and chronic psychological stressors on the immune system and development of coronary artery disease (CAD). Firstly, it illustrates how psychological stressors change endothelial function and lead to chemotaxis. Secondly, acute psychological stressors lead to leukocytosis, increased natural killer cell cytotoxicity and reduced proliferative response to mitogens while chronic psychological stressors may lead to adverse health effects. This will result in changes in cardiovascular function and development of CAD. Thirdly, acute and chronic psychological stressors will increase haemostatic factors and acute phase proteins, possibly leading to thrombus formation and myocardial infarction. The evidence for the effects of acute and chronic psychological stress on the onset and progression of CAD is consistent and convincing. This paper also highlights potential research areas and implications of early detection of immunological changes and cardiovascular risk in people under high psychological stress.
Acute-Phase Proteins ; Coronary Artery Disease ; immunology ; psychology ; Humans ; Inflammation ; psychology ; Myocardial Infarction ; immunology ; psychology ; Stress, Psychological ; immunology ; Thrombosis ; immunology ; psychology

INTRODUCTIONThis study aims to determine the attitudes of Asian elderly patients towards invasive life support measures, the degree of patient-surrogate concordance in end-of-life decision making, the extent to which patients desire autonomy over end-of-life medical decisions, the reasons behind patients' and surrogates' decisions, and the main factors influencing patients' and surrogates' decision-making processes. We hypothesize that there is significant patient-surrogate discordance in end-of-life decision making in our community.

MATERIALS AND METHODSThe patient and surrogate were presented with a hypothetical scenario in which the patient experienced gradual functional decline in the community before being admitted for life-threatening pneumonia. It was explained that the outcome was likely to be poor even with intensive care and each patient-surrogate pair was subsequently interviewed separately on their opinions of extraordinary life support using a standardised questionnaire. Both parties were blinded to each other's replies.

RESULTSIn total, 30 patients and their surrogate decision-makers were interviewed. Twenty-eight (93.3%) patients and 20 (66.7%) surrogates rejected intensive care. Patient-surrogate concurrence was found in 20 pairs (66.7%). Twenty-four (80.0%) patients desired autonomy over their decision. The patients' and surrogates' top reasons for rejecting intensive treatment were treatment-related discomfort, poor prognosis and financial cost. Surrogates' top reasons for selecting intensive treatment were the hope of recovery, the need to complete final tasks and the sanctity of life.

CONCLUSIONThe majority of patients desire autonomy over critical care issues. Relying on the surrogates' decisions to initiate treatment may result in treatment against patients' wishes in up to one-third of critically ill elderly patients.

Advance Directive Adherence ; Aged ; Aged, 80 and over ; Attitude ; Critical Care ; psychology ; Critical Illness ; psychology ; therapy ; Decision Making ; Dissent and Disputes ; Female ; Humans ; Male ; Personal Autonomy

The United Nations has identified the training and education of healthcare professionals and care providers involved in the care of older persons as a global priority. Singapore is no exception as it faces a rapidly ageing population. Older people have many medical needs of varying dimensions and their care requires a multidisciplinary healthcare team. The current status of geriatric education of health professionals involved in elderly care in Singapore is discussed in this paper. Important issues raised include the disparity between professions in the stages of development of geriatric education, questions on the adequacy of numbers and training of healthcare professionals providing geriatric care, as well as the need for geriatric education of caregivers.
Aged ; Geriatric Nursing ; education ; Health Personnel ; education ; Humans ; Singapore