Purpose: This fMRI study is about modelling the effective connectivity between Heschl’s gyrus (HG) and the superior temporal gyrus (STG) in human primary auditory cortices. Materials & methods: Ten healthy male participants were required to listen to white noise stimuli during functional magnetic resonance imaging (fMRI) scans. Statistical parametric mapping (SPM) was used to generate individual and group brain activation maps. For input region determination, two intrinsic connectivity models comprising bilateral HG and STG were constructed using dynamic causal modelling (DCM). The models were estimated and inferred using DCM while Bayesian Model Selection (BMS) for group studies was used for model comparison and selection. Based on the winning model, six linear and six non-linear causal models were derived and were again estimated, inferred, and compared to obtain a model that best represents the effective connectivity between HG and the STG, balancing accuracy and complexity. Results: Group results indicated significant asymmetrical activation (puncorr < 0.001) in bilateral HG and STG. Model comparison results showed strong evidence of STG as the input centre. The winning model is preferred by 6 out of 10 participants. The results were supported by BMS results for group studies with the expected posterior probability,r = 0.7830 and exceedance probability, φ = 0.9823. One-sample t-tests performed on connection values obtained from the winning model indicated that the valid connections for the winning model are the unidirectional parallel connections from STG to bilateral HG (p < 0.05). Subsequent model comparison between linear and non-linear models using BMS prefers non-linear connection (r = 0.9160, φ = 1.000) from which the connectivity between STG and the ipsi- and contralateral HG is gated by the activity in STG itself. Conclusion: We are able to demonstrate that the effective connectivity between HG and STG while listening to white noise for the respective participants can be explained by a non-linear dynamic causal model with the activity in STG influencing the STG-HG connectivity non-linearly.

In this study, functional magnetic resonance imaging (fMRI) is used to investigate func-tional specialisation in human auditory cortices during listening. A silent fMRI paradigm was used to reduce the scanner sound artefacts on functional images. The subject was instructed to pay attention to the white noise stimulus binaurally given at an inten-sity level of 70 dB higher than the hearing level for normal people. Functional speciali-sation was studied using the Matlab-based Statistical Parametric Mapping (SPM5) software by means of fixed effects (FFX), random effects (RFX) and conjunction analyses. Individual analyses on all subjects indicated asymmetrical bilateral activation of the left and right hemispheres in Brodmann areas (BA) 22, 41 and 42, involving the primary and secondary auditory cortices. The percentage of signal change is larger in the BA22, 41 and 42 on the right as compared to the ones on the left (p>0.05). The average number of activated voxels in all the respective Brodmann areas are higher in the right hemisphere than in the left (p>0.05). FFX results showed that the point of maximum intensity was in the right BA41 whereby 599±1 activated voxels were ob-served in the right temporal lobe as compared to 485±1 in the left temporal lobe. The RFX results were consistent with that of FFX. The analysis of conjunction which fol-lowed, showed that the right BA41 and left BA22 as the common activated areas in all subjects. The results confirmed the specialisation of the right auditory cortices in pro-cessing non verbal stimuli.

Introduction: This study aimed to develop and examine the validity and reproducibility of a semi-quantitative food frequency questionnaire (FFQ) among Malay pregnant women in Kelantan, Malaysia. Methods: A total of 177 Malay pregnant women participated in the validation study while 85 of them participated in the reproducibility study which was carried out in the antenatal clinic of Universiti Sains Malaysia Hospital. The newly developed FFQ was validated against two 24-hour dietary recalls (DR). The FFQ was repeated 20 to 28 days apart. Results: Results showed that the FFQ moderately over estimated the nutrient and food intakes compared to the DR. Spearman correlation coefficients for nutrients ranged from 0.24 (fat) to 0.61 (calcium) and for foods, ranged from 0.13 (organ meats, onion and garlic) to 0.57 (malt drink). For nutrients, 72 to 85% of women were classified into the correct quartiles from the FFQ and the DR while for foods, 67 to 85% of women were classified correctly. Bland-Altman plot showed relatively good agreement between these two dietary methods. The intra-class correlation (ICC) was used to estimate reproducibility. It ranged from 0.75 (vitamin C) to 0.94 (phosphorus) for nutrients while it ranged from 0.73 (confectionary) to 0.96 (coffee) for foods. Conclusion: On average, at least 90% of pregnant women were correctly classified into the quartiles for nutrients and foods from the two sets of the FFQ. The FFQ presented acceptable reproducibility and appears to be a valid tool for categorising pregnant women according to dietary intake.

Scanning electron microscope (SEM) images of dust mites, Suidasia pontifica, is presented to provide an improved visualization of the taxonomic characters of these mites. Suidasia pontifica can easily be identified by its scale-like cuticle, presence of external vertical setae (ve), longer external scapular setae (sce) compared to internal scapular setae (sci) and 3 ventral spines on apex of tarsus I. The differences in morphology of male and female S. pontifica are also discussed.

Objective: To study the role of antibodies in protection against Leishmania tropica (L. tropica) infection in the experimental model of BALB/c mice.Methods: BALB/c mice were vaccinated against L. tropica by soluble Leishmania antigen or recombinant L. tropica stress-inducible protein-1 (LtSTI1) of L. tropica, and against Leishmania major (L. major) by soluble Leishmania antigen. Monophosphoryl lipid A was used as an adjuvant. The L. tropica- or L. major-vaccinated mice were challenged by L. tropica or L. major, respectively. The levels of anti-Leishmania antibodies (IgG1 and IgG2a) were determined after vaccination and after challenge. Results: All vaccinated groups caused a higher antibody response in comparison with the control group. The L. major-vaccinated group showed lower IgG1 response than the control group after the challenge. Conversely, in L. tropica-vaccinated mice, the levels of antibodies were higher than the control group. Moreover, the group receiving rLtSTI1 and monophosphoryl lipid A showed higher levels of antibodies than those of the rLtSTI1 group. In vaccinated mice, antibody responses against L. tropica remained high until 16 weeks after the challenge. Conclusions: The higher levels of post-challenge antibodies are associated with protective vaccination against L. tropica infection of BALB/c mice. Our findings provide new insight into the association of antibody with vaccine-induced protective immunity against L. tropica infection. More studies are needed to clarify the role of antibody in protection against L. tropica.

Aims: The presents study examines the purification and characterization of a chitinase from S. maltophilia SJ602 strain isolated from a soil sample collected from Jamia Hamdard, New Delhi. Methodology and Results: The purification steps included chitin affinity using colloidal chitin as the affinity matrix and column chromatography using Sephadex G-100. The chitinase was purified to 66 fold having a yield of 17%. The molecular weight of the chitinase was found to be around 29 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The pH and temperature optima of the purified chitinase were found to be at pH 5.5 and 60 °C, respectively. Conclusion, Significance and Impact of the study: Besides showing a significant yield, the enzyme has a high thermal stability which has its applicability in the recycling of chitin waste.

Since the outbreak of the novel influenza H1N1 in April 2009 in Mexico, more then half a million cases have been recorded with more then 6000 deaths. In contrast to seasonal flu, this virus appears to have a predilection for the young, obese and pregnant. It’s most important and almost fatal complication is Acute Respiratory Distress Syndrome (ARDS). Intensive care units (ICU) around the world have scrambled to upgrade various treatment modalities including high frequency oscillation ventilation, inotropes, antivirals and antibiotics in an effort to reduce the mortality arising out of this complication. More importantly, this complication appears reversible if adequate and early therapy is instituted. In particular, rescue therapies that allow the lung to rest appear to have brought success in some clinical settings. This article describes the experiences of seven centers that have used various modalities as rescue therapy in patients having Acute Respiratory Distress Syndrome (ARDS). The experiences in 13 patients at the University of Michigan, 58 in Mexico, 168 in Canada, 180 patients at Leicester UK, 194 in Australia and New Zealand and case reports from Hong Kong and Singapore are described.

Hydroxyapatite is the main component of the bone which is a potential biomaterial substance that can be applied in orthopaedics. In this study, the biocompatibility of this biomaterial was assessed using an in vitro technique. The cytotoxicity and genotoxicity effect of HA2 and HA3 against L929 fibroblast cell was evaluated using the MTT Assay and Alkaline Comet Assay respectively. Both HA2 and HA3 compound showed low cytotoxicity effect as determined using MTT Assay. Cells viability following 72 hours incubation at maximum concentration of both HA2 and HA3 (200 mg/ml) were 75.3 +/- 8.8% and 86.7 +/- 13.1% respectively. However, the cytotoxicity effect of ZnSO4.7H2O as a positive control showed an IC50 values of 46 mg/ml (160 microM). On the other hand, both HA2 and HA3 compound showed a slight genotoxicity effect as determined using the Alkaline Comet Assay following incubation at the concentration 200 mg/ml for 72 hours. This assay has been widely used in genetic toxicology to detect DNA strand breaks and alkali-labile site. The percentage of the cells with DNA damage for both substance was 27.7 +/- 1.3% and 15.6 +/- 1.0% for HA2 and HA3 respectively. Incubation of the cells for 24 hours with 38 microg/ml (IC25) of positive control showed an increase in percentage of cells with DNA damage (67.5 +/- 0.7%). In conclusion, our study indicated that both hydroxyapatite compounds showed a good biocompatibility in fibroblast cells.
Biocompatible Materials/*toxicity ; Bone Substitutes/*toxicity ; Cell Survival/drug effects ; *DNA Damage ; Hydroxyapatites/*toxicity ; L Cells (Cell Line) ; *Mutagenicity Tests ; *Prostheses and Implants

Peripheral neuropathy is highly associated with foot complications among diabetics. This study aimed to identify risk factors associated with the development of peripheral neuropathy in diabetic patients and their association with degree of severity of peripheral neuropathy. A cross-sectional study was conducted in follow-up clinics at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Malaysia involving 72 diabetic patients and 19 controls. Exclusion criteria were those with amputated limbs, gross foot deformity and existing peripheral neuropathy. Controls were non diabetics who walked normally, had no history of foot problem and attended the clinic as subjects’ companion. Quantitative assessment of neuropathy was done using Semmes-Weinstein monofilament. Neuropathy Disability Score (NDS) were used to quantify severity of diabetic neuropathy. Spearman’s Rank test and Mann-Whitney test were used to determine correlation between variables and their differences. Logistic regression analysis was used to determine risk factors associated with peripheral neuropathy. The mean HbA1c among diabetics was 8.6% + 4.1, and mean NDS was 7.0 + 6.0. A total of 79.1% demonstrated various level of neuropathy with presence of callus was associated with higher NDS scores. Older age (P=0.02), body weight (P=0.03), HbA1c (P=0.005) and duration of diabetes (P <0.005) showed positive correlation with NDS. Proper foot care program for diabetics should include recognition of the callus, with special emphasis given to those with heavier weight and increasing age.

Objective: To compare limiting dilution assay and real-time PCR methods in Leishmania tropica parasite load measurement in vaccinated mice.Methods: BALB/c mice were vaccinated by Leishmania tropica soluble Leishmania antigen or recombinant Leishmania tropica stress-inducible protein-1 with/without adjuvant. After three vaccinations, mice were challenged by Leishmania tropica promastigotes. Two months after challenge, the draining lymph nodes of mice footpad were removed and parasite load was assayed by limiting dilution assay and real-time PCR methods. Limiting dilution assay was done by diluting tissue samples to extinction in a biphasic medium. For real-time PCR, DNA of the lymph nodes was extracted, equal dilutions of each sample were prepared and hot-start real-time PCR was done using appropriate primers. The data of the two methods were compared by appropriate statistical methods. Results: Both methods were able to measure different levels of parasite load in vaccinated/unvaccinated mice. In addition, wherever parasite load of a group was estimated high (or low) by one method, the estimated parasite load by another method was the same, although statistically significant differences were found between some groups. Conclusions: Both methods lead to approximately similar results in terms of differentiating parasite load of the experimental groups. However, due to the lower errors and faster process, the real-time PCR method is preferred.