Size-controlled and monodispersed silver nanoparticles were synthesized from an aqueous solution containing silver nitrate as a metal precursor, polyvinyl alcohol as a capping agent, isopropyl alcohol as hydrogen and hydroxyl radical scavengers, and deionized water as a solvent with a simple radiolytic method. The average particle size decreased with an increase in dose due to the domination of nucleation over ion association in the formation of the nanoparticles by gamma reduction. The silver nanoparticles exhibit a very sharp and strong absorption spectrum with the absorption maximum λmax blue shifting with an increased dose, owing to a decrease in particle size. The absorption spectra of silver nanoparticles of various particle sizes were also calculated using a quantum physics treatment and an agreement was obtained with the experimental absorption data. The results suggest that the absorption spectrum of silver nanoparticles possibly derived from the intra-band excitations of conduction electrons from the lowest energy state (n = 5, l = 0) to higher energy states (n ≥ 6; Δl = 0, ±1; Δs = 0, ±1), allowed by the quantum numbers principle. This demonstrates that the absorption phenomenon of metal nanoparticles based on a quantum physics description could be exploited to be added into the fundamentals of metal nanoparticles and the related fields of nanoscience and nanotechnology.
Cancer is known to induce or alter the O-glycosylation of selective proteins that may eventually be excreted in the patients' urine. The present study was performed to identify O-glycosylated proteins that are aberrantly excreted in the urine of patients with early stage ovarian cancer (OCa). These urinary glycoproteins are potential biomarkers for early detection of OCa. In this study, urinary proteins of patients with early stage OCa and age-matched OCa negative women were subjected to two-dimensional gel electrophoresis and detection using a lectin that binds to the O-glycosylated proteins. Our analysis demonstrated significant enhanced expression of clusterin and leucine-rich alpha-2-glycoprotein, but lower levels of kininogen in the urine of the OCa patients compared to the controls. The different altered levels of these urinary glycoproteins were further confirmed using competitive ELISA. Our data are suggestive of the potential use of the aberrantly excreted urinary O-glycosylated proteins as biomarkers for the early detection of OCa, although this requires further validation in a large clinically representative population.
A 31-year-old Malaysian man was presented with an episode of seizures by the roadside, after having been recently diagnosed as HIV positive accompanied with miliary tuberculosis. On physical examination, he was oriented to person, but not to time or place. There was no neck stiffness or papilloedema. The other systemic examination was unremarkable. Chest examination revealed crepitations at the upper zone of the right lung. After diagnosis suspicion, the case was confirmed as toxoplasma encephalitis by MRI and serological tests. Patient was treated with trimethoprim/sulfamethoxazole 480-2400 mg/day with folinic acid supplement for 60 days. Two months later, a repeat brain MRI showed resolution of the cerebral lesions.
MeSH terms: Adult; Anti-Infective Agents/therapeutic use; Diagnosis, Differential; Humans; Magnetic Resonance Imaging; Male; AIDS Dementia Complex/diagnosis; Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use; Toxoplasmosis, Cerebral/diagnosis*; Toxoplasmosis, Cerebral/drug therapy*; Tuberculoma, Intracranial/diagnosis
Microbial fuel cells (MFCs) represent an emerging technology that focuses on power generation and effluent treatment. This review compiles articles related to MFCs using azo dye as the substrate. The significance of the general components in MFCs and systems of MFCs treating azo dye is depicted in this review. In addition, degradation of azo dyes such as Congo red, methyl orange, active brilliant red X-3B, amaranth, reactive blue 221, and acid orange 7 in MFCs are summarized. Further exploration and operational modification are suggested to address the challenges of complete removal of azo dye with maximum power generation in an MFC. In addition, a sequential treatment system with MFCs is suggested for complete mineralization of azo dye.
MeSH terms: Amaranth Dye/chemistry; Azo Compounds/chemistry*; Bioelectric Energy Sources*
The goal of consensus clustering methods is to find a consensus partition that optimally summarizes an ensemble and improves the quality of clustering compared with single clustering algorithms. In this paper, an enhanced voting-based consensus method was introduced and compared with other consensus clustering methods, including co-association-based, graph-based, and voting-based consensus methods. The MDDR and MUV data sets were used for the experiments and were represented by three 2D fingerprints: ALOGP, ECFP_4, and ECFC_4. The results were evaluated based on the ability of the clustering method to separate active from inactive molecules in each cluster using four criteria: F-measure, Quality Partition Index (QPI), Rand Index (RI), and Fowlkes-Mallows Index (FMI). The experiments suggest that the consensus methods can deliver significant improvements for the effectiveness of chemical structures clustering.
The fascinating and serendipitous discovery, in 1976, of the characteristic viscoelastic behavior of wormlike micelles of cetyltrimethylammonium salicylate (CTASa) surfactant solution at ~2×10(-4) M CTASa became a catalyst for an increasing interest in both industrial application and mechanism of the origin of micellar growth of this and related wormlike micellar systems. It has been perceived for more than three decades, based upon qualitative evidence, that the extent of the strength of the counterion (X) binding to ionic micelles determines the counterion-induced micellar structural transition from spherical-to-small rodlike-to-linear long stiff/flexible rodlike/wormlike-to-entangled wormlike micelles. This perception predicts the presence of a possible quantitative correlation of counterionic micellar binding constants (KX) with counterion-induced micellar growth. The quantitative estimation of counterion binding affinity to cationic micelles, in terms of the values of the degree of counterion binding (βX), is concluded to be either inefficient or unreliable for moderately hydrophobic counterions (such as substituted benzoate ions). The values of KX, measured in terms of conventional ion exchange constants (KX(Y)), can provide a quantitative correlation between KX or KX(Y) (with a reference counterion Y=Cl(-) or Br(-)) and counterion-induced ionic micellar growth. A recent new semi-empirical kinetic (SEK) method provides the estimation of KX(Y) for Y=Br as well as ratio of counterionic micellar binding constants KX/KBr (= RX(Br)) where the values of KBr and KX have been derived from the kinetic parameters in the presence of cationic spherical and nonspherical micelles, respectively. The SEK method has been used to determine the values of KX(Br) or RX(Br) for X=2-, 3- and 4-ClC6H4CO2(-). Rheometric measurements on aqueous CTABr/MX (MX=2-,3- and 4-ClBzNa) solutions containing 0.015 M CTABr and varying values of [MX] reveal the presence of spherical micelles for MX=2-ClBzNa and long linear as well as entangled wormlike micelles for MX=3- and 4-ClBzNa. The respective values of KX(Br) or RX(Br) of 5.7, 50 and 48 for X=2-, 3- and 4-ClBz(-) give a quantitative correlation with the rheometric measurements of the structural features of micelles of 0.015 M CTABr solutions containing 2-, 3- and 4 ClBzNa.
Forensic identification of juvenile skulls is a problem area. Although the skull suture patterns have been suggested for use in individualizing human remains by comparing antemortem and postmortem radiographs, the age at which such patterns stabilize and can be useful for identification had been indicated as 7 years. Subsequent researchers have also concurred that antemortem and postmortem radiographs taken after the 7th year would be sufficient to meet the Daubert standard criteria for identifying skulls using radiographs. The suggestions regarding the lower age limit for stabilization of suture patterns have not been verified so far. In this research, the patterns of the sutures in the ectocranial and endocranial surfaces of the lambdoid region in 22 juvenile skulls (age range 1-10 years) and 100 adult skulls (age range 17-70 years) were studied for the relative incidence of different types of suture patterns. The radiographic recordings of the suture patterns in the juvenile skulls were also compared with the patterns seen in the ectocranial and endocranial surfaces. The findings of this study support the proposition that the suture patterns are plastic during the juvenile stage and that they undergo significant remodeling during growth into adulthood. Indicating the possibility of growth related alterations in the sutural morphology, the onset of adulthood is suggested as the age for stabilization of suture patterns in the context of prescribing standards for such criteria as those relating to Daubert.
MeSH terms: Adolescent; Adult; Age Determination by Skeleton/methods*; Aged; Child; Child, Preschool; Cranial Sutures/growth & development*; Cranial Sutures/radiography*; Female; Humans; Infant; Male; Middle Aged; Forensic Anthropology; Young Adult
OBJECTIVE: The prime purpose of this study is to assess HIV/AIDS-related self-stigma and discrimination (S&D) attitudes and associated factors using multivariate analysis of data from the 2010-11 National Survey of Understanding the Root of HIV/AIDS Related Stigma and Discrimination.
METHOD: A national telephone survey was carried out with 2271 of the Malaysian public aged 18-60 years. The sample was contacted by random digit dialing covering the whole of Peninsular Malaysia from December 2010 to May 2011. The HIV-transmission knowledge, HIV-related self-stigma, and public stigma were investigated.
RESULTS: Despite high level of HIV-transmission knowledge [mean (SD)=10.56 (2.42), mean score at 70th percentile] the respondents in this study had moderate levels (mean scores near midpoints) of self-stigma and public stigma attitudes. HIV-transmission knowledge score was not significantly correlated with self-stigma score, but showed a significantly small positive effect (r<0.2) for public stigma scores. Ethnicity is the strongest correlate of HIV-transmission knowledge, self-stigma, and public stigma attitudes in the multivariate analyses. Other significant correlates were age, socioeconomic group, and urban-rural setting.
CONCLUSIONS: The root causes of HIV stigma and discriminatory attitudes were not associated with knowledge deficiency. Interventions should be oriented towards promoting de-stigmatization of HIV/AIDS, and tailored socio-culturally.
KEYWORDS: Discriminatory; HIV/AIDS; Knowledge; Stigma
MeSH terms: Adolescent; Adult; Age Factors; Cross-Sectional Studies; Female; Humans; Health Knowledge, Attitudes, Practice; Malaysia/epidemiology; Male; Middle Aged; Prejudice/psychology; Prejudice/statistics & numerical data*; Socioeconomic Factors; Stereotyping*; HIV Infections/psychology*; Prevalence; Young Adult; Social Stigma
This study aimed to determine the prevalence and early outcome of neural tube defects (NTDs) in Malaysia. This prospective study included all neonates with NTDs (spina bifida, anencephaly, encephalocoele) born in 2009 in 32 Malaysian hospitals in the Malaysian National Neonatal Network. The prevalence of NTDs was 0.42 per 1000 live births, being highest among the indigenous people of Sarawak (1.09 per 1000 live births) and lowest among Malaysians of Chinese descent (0.09 per 1000 live births). The most common type of NTDs was anencephaly (0.19 per 1000 live births), followed by spina bifida (0.11 per 1000 live births) and encephalocoele (0.07 per 1000 live births). Majority of the infants with anencephaly (94.5%, n = 51), 45.8% (n = 11) with encephalocoele and 9.5% (n = 4) with spina bifida died. The median duration of hospital stay was 4 (range: 0-161) days.
The spatial distribution of 19 polycyclic aromatic hydrocarbons (tPAHs) was quantified in aquacultures located in intertidal mudflats of the west coast of Peninsular Malaysia in order to investigate bioaccumulation of PAH in blood cockles, Anadara granosa (A. granosa). Fifty-four samples from environmental matrices and A. granosa were collected. The sampling locations were representative of a remote area as well as PAH-polluted areas. The relationship of increased background levels of PAH to anthropogenic PAH sources in the environment and their effects on bioaccumulation levels of A. granosa are investigated in this study. The levels of PAH in the most polluted station were found to be up to ten-fold higher than in remote areas in blood cockle. These high concentrations of PAHs reflected background contamination, which originates from distant airborne and waterborne transportation of contaminated particles. The fraction and source identification of PAHs, based on fate and transport considerations, showed a mix of petrogenic and pyrogenic sources. The relative biota-sediment accumulation factors (RBSAF), relative bioaccumulation factors from filtered water (RBAFw), and from suspended particulate matter (SPM) (RBAFSP) showed higher bioaccumulations of the lower molecular weight of PAHs (LMWs) in all stations, except Kuala Juru, which showed higher bioaccumulation of the higher molecular weight of PAHs (HMWs). Calculations of bioaccumulation factors showed that blood cockle can accumulate PAHs from sediment as well as water samples, based on the physico-chemical characteristics of habitat and behaviour of blood cockles. Correlations among concentrations of PAHs in water, SPM, sediment and A. granosa at the same sites were also found. Identification of PAH levels in different matrices showed that A. granosa can be used as a good biomonitor for LMW of PAHs and tPAHs in mudflats. Considering the toxicity and carcinogenicity of PAHs, the bioaccumulation by blood cockles are a potential hazard for both blood cockles and their consumers.
MeSH terms: Animals; Environmental Exposure*; Environmental Monitoring/methods*; Malaysia; Gas Chromatography-Mass Spectrometry; Polycyclic Hydrocarbons, Aromatic/metabolism*; Water Pollutants, Chemical/analysis; Water Pollutants, Chemical/metabolism*; Geologic Sediments/analysis*; Arcidae/drug effects; Arcidae/metabolism*; Particulate Matter/analysis; Particulate Matter/metabolism*
This study presents a novel application of near infrared (NIR) spectral linearisation for measuring the soluble solids content (SSC) of carambola fruits. NIR spectra were measured using reflectance and interactance methods. In this study, only the interactance measurement technique successfully generated a reliable measurement result with a coefficient of determination of (R2) = 0.724 and a root mean square error of prediction for (RMSEP) = 0.461° Brix. The results from this technique produced a highly accurate and stable prediction model compared with multiple linear regression techniques.
MeSH terms: Calibration; Fruit/chemistry*; Solubility; Linear Models; Spectroscopy, Near-Infrared/methods*
The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment.
OBJECTIVE: To determine the prevalence of retinopathy in type 2 diabetic patients with micoalbuminuria and to evaluate the association of risk factors with prevalence of retinopathy in these patients.
MATERIAL AND METHODS: A fundus examination of 137 patients suffering from type 2 diabetes mellitus with microalbuminuria was done, with direct ophthalmoscope/ binocular indirect ophthalmoscope after dilating the pupils with 1 % tropicamide eye drops. Retinal changes were graded as no retinopathy, non-proliferative retinopathy, proliferative retinopathy and maculopathy. The association of the duration of diabetes, control of diabetes, hypertension, hyperlipidemia, smoking, obesity and peripheral neuropathy was assessed with the prevalence of retinopathy in these patents.
RESULTS: The mean age of the patients was 58 years (range 35 - 79 years); 62 % were females, and 49.6 % were Chinese. Diabetic retinopathy was seen in 36.5 % of the patients - non proliferative in 29.2 %, proliferative in 7.3 % and maculopathy in 5.1 % of patients. A longer duration of diabetes (p = 0.002), poor control of diabetes (p = 0.002), presence of hypertension (p = 0.03), and presence of peripheral neuropathy (p = 0.001) were significantly associated with the prevalence of retinopathy; while hyperlipidemia (p = 0.29), smoking (p = 0.43) and obesity (p = 0.43) were not associated with retinopathy.
CONCLUSION: Retinopathy was seen in 36.5 % of type 2 diabetic patients with microalbuminuria; 7.3 % had proliferative retinopathy and 5.1 % maculopathy (both sight threatening changes). All diabetic patients with microalbuminuria should be screened for retinopathy so that treatment can be instituted in the required patients to prevent ocular morbidity/ blindness.
Hematopoietic stem cell transplantation (HCT) utilizing non-myeloablative (NMA) and reduced-intensity conditioning (RIC) regimens (collectively referred to as reduced-toxicity HCT, RT-HCT) has become a viable therapeutic option for patients with hematological malignancies who are ineligible for standard myeloablative conditioning transplantation (MA-HCT). RT-HCT has been shown to induce stable engraftment with low toxicity, and to produce similar overall and progression-free survival (PFS) when compared to MA-HCT in acute myeloid leukemia and myelodysplastic syndrome. The best results for RT-HCT have been reported for patients with disease that is in remission, indolent and chemosensitive, and with a strong graft-versus-malignancy effect. Chronic graft-versus-host disease seems to correlate with a lower relapse rate and better PFS. RT-HCT is inferior when performed in poor risk or advanced disease, due to high relapse rates. A search for novel strategies that includes the most appropriate conditioning regimens and post-transplant immunomodulation protocols with more intensive anti-malignancy activity but limited toxicity is in progress. This review provides an update on the results of clinical studies of RT-HCT, and discusses possible indications and investigative strategies for improving the clinical outcomes of RT-HCT for the major hematological malignancies.
Oncolytic viruses have been extensively evaluated for anticancer therapy because this virus preferentially infects cancer cells without interfering with normal cells. Newcastle Disease Virus (NDV) is an avian virus and one of the intensively studied oncolytic viruses affecting many types of cancer including glioma. Nevertheless, the capability of NDV infection on heterogeneous glioma tissue in a cerebrospinal fluid atmosphere has never been reported. Recently, Rac1 is reported to be required for efficient NDV replication in human cancer cells and established a link between tumourigenesis and sensitivity to NDV. Rac1 is a member of the Rho GTPases involved in the regulation of the cell migration and cell-cycle progression. Rac1 knockdown leads to significant inhibition of viral replication. In this work, we demonstrated that NDV treatment led to significant reduction of tumour tissue viability of freshly isolated heterogeneous human brain tumour slice, known as an ex vivo glioma acute slice (EGAS). Analysis of gene expression indicated that reduced tissue viability was associated with downregulation of Rac1. However, the viability reduction was not persistent. We conclude that NDV treatment induced EGAS viability suppression, but subsequent downregulation of Rac1 gene may reduce the NDV replication and lead to regrowth of EGAS tissue.
The stone fish (Actinopyga lecanora) ethanolic and methanolic tissue extracts were investigated for total phenolic contents (TPCs) as well as antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) radical scavenging activity and ferric reducing antioxidant power (FRAP) assays. Both extracts showed low amount of phenolics (20.33 to 17.03 mg of gallic acid equivalents/100 g dried sample) and moderate antioxidant activity (39% to 34% DPPH(•) radical scavenging activity and 23.95 to 22.30 mmol/100 mL FeSO4 FRAP value). Enzymatic proteolysis was carried out in order to improve the antioxidant activity using six commercially available proteases under their optimum conditions. The results revealed that the highest increase in antioxidant activity up to 85% was obtained for papain-generated proteolysate, followed by alcalase (77%), trypsin (75%), pepsin (68%), bromelain (68%), and flavourzyme (50%) as measured by DPPH(•) radical scavenging activity, whilst for the FRAP value, the highest increase in the antioxidant activity up to 39.2 mmol/100 mL FeSO4 was obtained for alcalase-generated proteolysate, followed by papain (29.5 mmol/100 mL FeSO4), trypsin (23.2 mmol/100 mL FeSO4), flavourzyme (24.7 mmol/100 mL FeSO4), bromelain (22.9 mmol/100 mL FeSO4), and pepsin (20.8 mmol/100 mL FeSO4). It is obvious that proteolysis of stone fish tissue by proteolytic enzymes can considerably enhance its antioxidant activity.
Psychosocial stress is reported to be one of the main causes of obesity. Based on observations in studies that relate stress and gut inflammation to obesity, the present study hypothesized that chronic stress, via inflammation, alters the expression of nutrient transporters and contributes to the development of metabolic syndrome. Rats were exposed to restraint stress for 4 h/day for 5 days/week for eight consecutive weeks. Different segments of rat intestine were then collected and analysed for signs of pathophysiological changes and the expression of Niemann-Pick C1-like-1 (NPC1L1), sodium-dependent glucose transporter-1 (SLC5A1, previously known as SGLT1) and facilitative glucose transporter-2 (SLC2A2, previously known as GLUT2). In a separate experiment, the total anti-oxidant activity (TAA)-time profile of control isolated intestinal segments was measured. Stress decreased the expression of NPC1L1 in the ileum and upregulated SLC5A1 in both the jejunum and ileum and SLC2A2 in the duodenum. Inflammation and morphological changes were observed in the proximal region of the intestine of stressed animals. Compared with jejunal and ileal segments, the rate of increase in TAA was higher in the duodenum, indicating that the segment contained less anti-oxidants; anti-oxidants may function to protect the tissues. In conclusion, stress alters the expression of hexose and lipid transporters in the gut. The site-specific increase in the expression of SLC5A1 and SLC2A2 may be correlated with pathological changes in the intestine. The ileum may be protected, in part, by gut anti-oxidants. Collectively, the data suggest that apart from causing inflammation, chronic stress may promote sugar uptake and contribute to hyperglycaemia.
BACKGROUND: Worldwide, the population is ageing, resulting in an associated increase in dementia prevalence. Forgetfulness in elderly people is often perceived as normal in some local cultures and thus, the early detection of dementia in primary care requires detection of symptoms other than memory complaints.This study was conducted to screen elderly patients for early dementia in primary care using a newly developed Early Dementia Questionnaire (EDQ) and comparing it with a standard assessment tool, the Mini Mental State Examination (MMSE).
METHODS: A cross-sectional study was conducted on a group of elderly patients using convenience sampling of consecutive patients. Elderly depression was excluded using the Geriatric Depression Scale (GDS). Exclusion criteria also included known cases of dementia. Inclusion criteria included a score of 5 or less in GDS and the presence of a reliable informant. A face-to-face interview was done using the EDQ with the patient and informant to elicit symptoms of early dementia. If the informant was not present, a telephone interview was used instead. The patient was then assessed with the Mini Mental State Examination (MMSE) using a cut-off point of 21.
RESULTS: Prevalence of dementia among 155 subjects was 52.3% by EDQ and 15.5% by MMSE. The EDQ demonstrated a sensitivity of 79.2% with specificity of 52.7%. Positive predictive value (PPV) of EDQ was 23.5% with the negative predictive value (NPV) of 93.2%. The strongest predictor of possible early dementia was complaints of memory problems (OR 26.22; 95% CI 2.03-338.14) followed by complaints of concentration problems (OR 14.33; 95% CI 5.53-37.12), emotional problems (OR 4.75; 95% CI 1.64-13.81) and sleep disturbances (OR 3.14; 95% CI 1.15-8.56). Socio-demographic factors, medical problems and smoking status were not associated with possible dementia (p>0.05), despite that 60-70% of the elderly had chronic illnesses.
CONCLUSION: The EDQ is a promising alternative to MMSE for screening of early dementia in primary care.
MeSH terms: Adult; Aged; Ambulatory Care Facilities; China/ethnology; Cross-Sectional Studies; Dementia/diagnosis*; Female; Humans; India/ethnology; Malaysia; Malaysia/ethnology; Male; Mass Screening/instrumentation*; Primary Health Care/standards*; Surveys and Questionnaires; Sensitivity and Specificity; Prevalence; Early Diagnosis*
This is the first case of Plasmodium knowlesi infection in a Japanese traveller returning from Malaysia. In September 2012, a previously healthy 35-year-old Japanese man presented to National Center for Global Health and Medicine in Tokyo with a two-day history of daily fever, mild headaches and mild arthralgia. Malaria parasites were found in the Giemsa-stained thin blood smear, which showed band forms similar to Plasmodium malariae. Although a nested PCR showed the amplification of the primer of Plasmodium vivax and Plasmodium knowlesi, he was finally diagnosed with P. knowlesi mono-infection by DNA sequencing. He was treated with mefloquine, and recovered without any complications. DNA sequencing of the PCR products is indispensable to confirm P. knowlesi infection, however there is limited access to DNA sequencing procedures in endemic areas. The extent of P. knowlesi transmission in Asia has not been clearly defined. There is limited availability of diagnostic tests and routine surveillance system for reporting an accurate diagnosis in the Asian endemic regions. Thus, reporting accurately diagnosed cases of P. knowlesi infection in travellers would be important for assessing the true nature of this emerging human infection.