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Fulltext Effects of degree of hydrolysis on physicochemical properties of cobia (Rachycentron canadum) frame hydrolysate

Amiza, M.A., Kong, Y.L., Faazaz, A.L.

International Food Research Journal, 2012;19(1):199-206.
MyJurnal

The effect of degree of hydrolysis (DH) on the physicochemical properties of cobia frame hydrolysate was determined. Three levels of degree of hydrolysis of cobia frame hydrolysate were studied, which were 53%, 71% and 96%. After enzymatic hydrolysis using Alcalase®, the samples were spray-dried. Cobia hydrolysate powder samples were analyzed for their proximate analysis and physicochemical properties. The proximate analysis showed significant differences in fat and ash content only. DH96 hydrolysate showed desirable essential amino acid profile for human requirement except for methionine and isoleucine. The study found that cobia frame hydrolysate had good colour, emulsifying capacity and excellent foaming properties. However, there were no significant differences in water-holding capacity, oil-holding capacity and peptide solubility among the hydrolysate samples. This study suggested that cobia frame hydrolysate is a potential ingredient and foaming agent for food industry.

Matched MeSH terms: Color
Fulltext The ability of Zea mays ears (Young Corn) powder in enhancing nutritional composition and changing textural properties and sensory acceptability of yeast bread

Lim, J.Y., Wan Rosli, W.l.

International Food Research Journal, 2013;20(2):799-804.
MyJurnal

Consumption of dietary fibre-rich food has been associated with various beneficial physiological properties and health effects. Presently, different types of natural fibre-rich ingredients are added into variety of bakery-based products to improve it fibre content for health promotional purposes. However, majority of these products are frequently added with imported dietary fibre ingredients. In the present study, bread samples were prepared with Zea mays ear (young corn) powder at the levels of either 2%, 4% or 6%. The bread samples were analyzed for nutritional composition, textural properties and sensory acceptance. Addition of young corn powder (YCP) at the level of 6% increases total dietary fibre (from 3.48% to 5.26%), moisture (from 25.64% to 26.55%), fat (from 4.35% to 4.61%) and protein content (from 9.13% to 9.51%) significantly. However, with the increasing of YCP levels in the bread, the carbohydrate content was decreased significantly (from 59.93% to 58.34%) while the ash content (from 0.95% to 0.99%) was not significantly affected. Results of texture profile analysis indicated that addition of YCP up to 6% not significantly affected the springiness (1.01-1.00) but significantly decreased cohesiveness (0.95-0.82). However, the addition of YCP up to 6% has increased hardness (0.18kg-0.57kg), gumminess (0.17kg-0.47kg) and chewiness (0.18kg-0.47kg) attributes of bread samples. On the other result, the sensory evaluation shows that the flavour score was not significantly affected by addition of YCP up to 4% (4.82-4.52) while the tenderness (4.53-4.42), elasticity (4.75-4.58), aroma (4.40-4.47), colour (4.93-4.55) and overall acceptance (4.80-4.35) scores were not significant affected up to 6%. In summary, breads with 4% addition of YCP were considered to be acceptable and potentially used in improving nutritional composition without changing sensory score.

Matched MeSH terms: Color
Fulltext Anthocyanins from Hibiscus sabdariffa, Melastoma malabathricum and Ipomoea batatas and its color properties

Aishah, B., Nursabrina, M., Noriham, A., Norizzah, A.R., Mohamad Shahrimi, H.

International Food Research Journal, 2013;20(2):827-834.
MyJurnal

There are many factors influencing the stability and color variation of natural colorant anthocyanin and pH is among the most significant factor. This study aims to determine the stability of the anthocyanins in freeze-dried Hibiscus sabdariffa, Melastoma malabathricum and Ipomoea batatas in various acidic pH (pH 2.0, 2.5, 3.0, 3.5, 4.0 and 4.5). Total monomeric anthocyanin, degradation index, color density and percent polymeric color were analyzed to determine anthocyanins degradation and their color variations. Among the samples, H.sabdariffa contain the highest monomeric anthocyanins (163.3 mg/L) followed by M. malabathricum (49.9 mg/L) and the lowest is I.batatas (13.8 mg/L). Monomeric anthocyanins from I.batatas were found to be very stable and not affected by changes in pH than in H. sabdariffa and M. malabathricum. However, degradation index (DI) of H. sabdariffa was the lowest with value of 0.365 ± 0.049 at pH 3.5. The lowest percentage of polymeric color (4.94 ± 0.64) was also shown by H. sabdariffa at pH 2.5 and maintained a deep red color with increasing pH indicating higher color stability compared to M. malabathricum and I. batatas. Overall, natural pigment in H. sabdariffa was found to be the most stable in both monomeric anthocyanin content and chromaticity properties. These results provided information that will further proven the potential usage of H. sabdariffa, M. malabathricum and I. batatas as natural coloring agents to replace the synthetic colorant in food and beverage industries.

Matched MeSH terms: Color; Coloring Agents
Fulltext Effects of Myristica fragrans Houtt. (Nutmeg) extract on chemical characteristic of raw beef during frozen storage

Zakaria, M.P.M., Abas, F., Rukayadi, Y.

International Food Research Journal, 2015;22(3):902-909.
MyJurnal

The objective of this study was to investigate the effect of nutmeg (Myristica fragrans Houtt.) extract at different concentrations on chemical characteristics of raw beef under frozen storage. Nutmeg extracts at concentrations of 0.25%, 0.65%, 1.25%, 2.50% and 5.00% (g/ml) were used to treat raw beef (2.5 × 2.5 × 1.0 cm; 4 ± 0.5 g) with dilution method. Treated samples were then individually packed in overwrapped trays and stored for 3 weeks at -18 ± 1oC. The effects of the extract on the chemical characteristics such as lipid oxidation, colour, pH, moisture, fat, and protein content of raw beef were evaluated at 0, 4, 7, 10, 14 and 21 days of storage. Lipid oxidation was evaluated based on thiobarbituric acid-reactive substance (TBARS) content. Colour of beef was observed by spectrophotometer in colorimetic parameters CIELabs. Values of pH were measured using pH meter. Moisture, fat and protein content were determined using method by Analysis Association of Official Analytical Chemists (AOAC). The result showed that extract at concentration of 1.25% inhibited TBARS value meaning that extract of 1.25% or more was able to maintain the oxidative stability of beef at -18oC. A 1.25% of extract was also able to maintain the redness (a*) of treated beef compared to untreated during frozen storage. The pH values of all samples beef decreased starting from 10th day of storage. Untreated samples (0.00%) showed the lowest pH values compared to other treated samples at the end day of storage. There was no significant different in term of protein content in all treated or untreated samples. However, fat and moisture content were significantly affected by the concentration of nutmeg extract. Treated beef was able to retain its moisture with only loss of moisture ranging from 0.2% – 2.00% while untreated samples had 5.00% loss of moisture. The fat content of untreated samples (0.00%) showed a reduction of 0.2% of fat content at the end of storage compared to all treated sample with only loss of 0.1% - 0.05%. Overall, nutmeg extract can be used to maintain the chemical characteristics of raw beef during storage for 3 weeks.

Matched MeSH terms: Color
Experimental and theoretical approach on the optical properties of zinc borotellurite glass doped with dysprosium oxide

Halimah MK, Ami Hazlin MN, Muhammad FD

Spectrochim Acta A Mol Biomol Spectrosc, 2018 Apr 15;195:128-135.
PMID: 29414569 DOI: 10.1016/j.saa.2017.12.054

A series of glass samples with chemical formula {[(TeO2)0.7(B2O3)0.3]0.7(ZnO)0.3}1-x(Dy2O3)xwhere x=0.01, 0.02, 0.03, 0.04 and 0.05M fraction were synthesized through conventional melt-quenching method. The most common way to fabricate a glass material is by fusion of two or more component oxides followed by their quenching. This technique is known as melt-quenching technique. Kaur et al. (2016) [1] highlighted that the melt-quenching method able to enhance the mechanical properties like hardness and flexural strength of the material. The nature of the glass systems is proven to be amorphous based on the XRD pattern. The FTIR spectra of the glass systems confirm the existence of five bands which are assigned for the BO4, BO3,TeO4and TeO3vibrational groups. The density of the glass systems is increased with the addition of Dy2O3while the molar volume is found to be inversely proportional to the density of the proposed glass. The optical properties of the glasses are determined through the absorption spectra obtained from the UV-VIS spectrophotometer. From the absorption spectra, the indirect and direct optical band gaps and the Urbach energy are found to be inversely proportional to each other. As the molar fraction of the Dy2O3increased, the optical band gaps are observed to increase as opposed to the Urbach energy. For this glass system, the values of refractive index, electronic polarizability, oxide ion polarizability and the optical basicity are found to decrease as the addition of the dysprosium oxide is increased. From the emission spectra, two intense blue and yellow emission bands are observed, which correspond to the4F9/2→6H15/2and4F9/2→6H13/2transitions of Dy3+ions respectively. The CIE chromaticity coordinates of the zinc borotellurite glass systems are found to be located in the white light region.

Matched MeSH terms: Color
Green synthesis of palm oil mill effluent-based graphenic adsorbent for the treatment of dye-contaminated wastewater

Teow YH, Nordin NI, Mohammad AW

Environ Sci Pollut Res Int, 2019 Nov;26(33):33747-33757.
PMID: 29754300 DOI: 10.1007/s11356-018-2189-6

Textile wastewater contains methylene blue (MB), a major coloring agent in textile industry. Activated carbon (AC) is the most widely used adsorbent in removing dyes from industrial wastewater. However, high production cost of AC is the major obstacle for its wide application in dye wastewater treatment. In this study, a sustainable approach in synthesizing graphenic adsorbent from palm oil mill effluent (POME), a potential carbonaceous source, has been explored. This new development in adsorption technique is considered as green synthesis as it does not require any binder during the synthesis process, and at the same time, it helps to solve the bottleneck of palm oil industry as POME is the main cause contributed to Malaysia's water pollution problem. The synthesized GSC was characterized through XRD, FESEM, and EDX. The adsorption performance of the synthesized GSC was evaluated by adsorption of MB. The effect of initial concentration of synthetic MB solution (1-20 mg/L) and weight of GSC (5-20 g) were investigated. A remarkable change in color of synthetic MB solution from blue to crystal clear was observed at the end of adsorption study. High efficiency of the synthesized GSC for dye-contaminated wastewater treatment is concluded.

Matched MeSH terms: Color; Coloring Agents
The incidence of post-operative deep vein thrombosis in general surgical patients of hospital universiti sains malaysia

Tun M, Shuaib IL, Muhamad M, Mat Sain AH, Ressang AS

Malays J Med Sci, 2004 Jan;11(1):75-80.
PMID: 22977363

The incidence of deep vein thrombosis is believed to be rare in Asians. During recent years, a few reports have appeared with high incidence in orthopaedic patients comparable to Western studies. This study was carried out to find out the incidence of post-operative deep vein thrombosis (DVT) after major surgical procedures in general surgical patients in an Asian population. In a prospective study of 45 consecutive Asian patients after major general surgery, colour-flow duplex scan of the legs as an initial screening was done twice within two weeks. Mean age of the patients was 54 years 5 months and 87% of patients were included in the moderate and high risk group for deep vein thrombosis. Ascending venography was used to confirm deep vein thrombosis on patients with equivocal or positive results from colour flow duplex scan. One patient showed positive evidence of post-operative deep vein thrombosis on colour flow duplex scan which was further confirmed by ascending venography; giving an incidence of 2.2%. The incidence of post-operative deep vein thrombosis in general surgical patients is lower than the Western studies.

Matched MeSH terms: Color
Effects of temperature on the physicochemical properties and total phenolic content of red and green chilies during postharvest storage

Mohd Akbar SS, Azmie NAA, Mohd Ali M

J Food Sci, 2025 Feb;90(2):e70023.
PMID: 39902949 DOI: 10.1111/1750-3841.70023

Chilies are usually packed and stored after harvesting for sale, which can result in quality loss and affect the edibility of the product. This study aimed to determine the effect of temperature on the physicochemical properties of red and green chilies during postharvest storage at three different temperatures (0, 5, and 25°C). The physicochemical analysis of chilies was conducted for 9 days to determine color changes, texture, pH, total soluble solids, and total phenolic content (TPC). All test data were statistically analyzed using two-way analysis of variance and Pearson's correlation coefficient to determine the relationship between physicochemical properties and the TPC. The study found that the TPC values decreased significantly at all temperatures for both red and green chilies. At 5°C, the TPC values were 3.42 mg GAE/g extract and 2.23 mg GAE/g extract for red and green chilies, respectively. The red chilies showed the lowest values of texture and TPC at 0°C, indicating poor preservation. The green chilies at 0°C had higher TPC values (4.74 mg GAE/g extract) but suffered from high firmness loss, whereas 25°C led to microbial growth. Therefore, the overall quality and market acceptability of both red and green chilies were ideal at 5°C due to better preservation of physical appearance. In conclusion, the ideal storage condition at 5°C can reduce qualitative and postharvest losses of red and green chilies by maintaining better texture and acceptable TPC values.

Matched MeSH terms: Color
Fulltext Comparison on testability of visual acuity, stereo acuity and colour vision tests between children with learning disabilities and children without learning disabilities in government primary schools

Abu Bakar NF, Chen AH

Indian J Ophthalmol, 2014 Feb;62(2):141-4.
PMID: 24008790 DOI: 10.4103/0301-4738.116481

Children with learning disabilities might have difficulties to communicate effectively and give reliable responses as required in various visual function testing procedures.

Matched MeSH terms: Color Vision/physiology*
Determination of optimum harvest maturity and physico-chemical quality of Rastali banana (Musa AAB Rastali) during fruit ripening

Kheng TY, Ding P, Abdul Rahman NA

J Sci Food Agric, 2012 Jan 15;92(1):171-6.
PMID: 21780132 DOI: 10.1002/jsfa.4559

A series of physico-chemical quality (peel and pulp colours, pulp firmness, fruit pH, sugars and acids content, respiration rate and ethylene production) were conducted to study the optimum harvest periods (either week 11 or week 12 after emergence of the first hand) of Rastali banana (Musa AAB Rastali) based on the fruit quality during ripening.

Matched MeSH terms: Color*
Effectiveness of a colour coded HbA1c graphical record in improving diabetes control in people with type 2 diabetes: a randomized control trial

Wong SS, Ng CJ, Liew SM, Hussein N

Diabetes Res Clin Pract, 2012 Feb;95(2):e41-4.
PMID: 22119614 DOI: 10.1016/j.diabres.2011.11.001

We conducted a six-month randomized-controlled-trial to evaluate the effectiveness of a colour-coded HbA1c-graphical record in improving HbA1c level among type 2 diabetes patients. There was an improvement in the mean HbA1c knowledge score but the usage of the colour-coded HbA1c-graphical record did not produce reduction in the HbA1c level.
Study site: Primary care clinic, University Malaya Medical Centre, Kuala Lumpur, Malaysia

Matched MeSH terms: Color*
Fulltext Did we do it right?--an evaluation of the colour coding system for antenatal care in Malaysia

Ravindran J, Shamsuddin K, Selvaraju S

Med J Malaysia, 2003 Mar;58(1):37-53.
PMID: 14556325

Identification of pregnancies that are at greater than average risk is a fundamental component of antenatal care. The objective of this study was to assess the level of appropriate management and outcomes among mothers with hypertensive disorders of pregnancy, postdates and anemia in pregnancy, and to determine whether the colour coding system had any effect on the maternal mortality ratios. A retrospective follow-through study confined to users of government health services in Peninsular Malaysia was carried out in 1997. The study areas were stratified according to their high or low maternal mortality ratios. The study randomly sampled 1112 mothers out of 8388 mothers with the three common obstetric problems in the selected study districts. The study showed that the prevalence of anemia, hypertensive disorders in pregnancy and postmaturity among mothers with these conditions were according to known international standards. There was no significant difference in the colour coding practices between the high and low maternal mortality areas. Inappropriate referrals were surprisingly lower in the areas with high maternal mortality. Inappropriate care by diagnosis and by assigned colour code were significantly higher in the areas with high maternal mortality. The assigned colour code was accurate in only 56.1% of cases in the low maternal mortality areas and in 55.8% of the cases in the high maternal mortality areas and these two areas did not differ significantly in their accurate assignment of the colour codes. The colour coding system, as it exists now should be reviewed. Instead, a substantially revised system that takes cognisance of evidence in the scientific literature should be used to devise a more effective system that can be used by health care personnel involved in antenatal care to ensure appropriate level of care and referrals.

Matched MeSH terms: Color*
Fulltext Prospective Application of Palm Oil Mill Boiler Ash as a Biosorbent: Effect of Microwave Irradiation and Palm Oil Mill Effluent Decolorization by Adsorption

Hamzah MH, Ahmad Asri MF, Che Man H, Mohammed A

Int J Environ Res Public Health, 2019 09 17;16(18).
PMID: 31533308 DOI: 10.3390/ijerph16183453

Common conventional biological treatment methods fail to decolorize palm oil mill effluent (POME). The present study focused on using the abundant palm oil mill boiler (POMB) ashes for POME decolorization. The POMB ashes were subjected to microwave irradiation and chemical treatment using H2SO4. The resultant adsorbents were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Brunauer-Emmett-Teller (BET) analyses. The adsorption efficiency was evaluated at various pH levels (2-8.5), adsorption dosages (3-15 g) in 200 mL, and contact times (1-5 h). The microwave-irradiated POMB-retained ash recorded the highest color removal of 92.31%, for which the best conditions were pH 2, 15 g adsorbent dosage in 200 mL, and 5 h of contact time. At these best treatment conditions, the color concentration of the treated effluent was analyzed using the method proposed by the American Dye Manufacturers Institute (ADMI). The color concentration was 19.20 ADMI, which complies with the Malaysia discharge standard class A. The Freundlich isotherm model better fit the experimental data and had a high R2 of 0.9740. Based on these results, it can be deduced that microwave-irradiated POMB-retained ash has potential applications for POME decolorization via a biosorption process.

Matched MeSH terms: Color*
Color, sensory and textural attributes of beef frankfurter, beef ham and meat-free sausage containing tomato pomace

Savadkoohi S, Hoogenkamp H, Shamsi K, Farahnaky A

Meat Sci, 2014 Aug;97(4):410-8.
PMID: 24769097 DOI: 10.1016/j.meatsci.2014.03.017

The present investigation focuses on the textural properties, sensory attributes and color changes of beef frankfurter, beef ham and meat-free sausage produced by different levels of bleached tomato pomace. The texture and color profile were performed using an instrumental texture analyzer and colorimeter. The findings indicated that tomato pomace-added sausages had higher water holding capacity (WHC) compared to that of commercial samples. The frankfurters containing 5 and 7% (w/w) tomato pomace had the highest redness (a*), chroma (C*) and color differences (ΔE) values, while the meat-free sausages containing 7% (w/w) tomato pomace had significant (p<0.05) values for lightness (L*) and yellowness (b*). Furthermore, there were no significant (p>0.05) color differences between beef ham samples (with and without tomato pomace). A significant progression in the textural hardness and chewiness of systems containing tomato pomace was observed as well as higher sensory scores by panelists. According to sensorial evaluations, bleached tomato pomace improved the consumer acceptability and preference.

Matched MeSH terms: Color*
Fulltext Bleeding detection in wireless capsule endoscopy videos - Color versus texture features

Pogorelov K, Suman S, Azmadi Hussin F, Saeed Malik A, Ostroukhova O, Riegler M, et al.

J Appl Clin Med Phys, 2019 Aug;20(8):141-154.
PMID: 31251460 DOI: 10.1002/acm2.12662

Wireless capsule endoscopy (WCE) is an effective technology that can be used to make a gastrointestinal (GI) tract diagnosis of various lesions and abnormalities. Due to a long time required to pass through the GI tract, the resulting WCE data stream contains a large number of frames which leads to a tedious job for clinical experts to perform a visual check of each and every frame of a complete patient's video footage. In this paper, an automated technique for bleeding detection based on color and texture features is proposed. The approach combines the color information which is an essential feature for initial detection of frame with bleeding. Additionally, it uses the texture which plays an important role to extract more information from the lesion captured in the frames and allows the system to distinguish finely between borderline cases. The detection algorithm utilizes machine-learning-based classification methods, and it can efficiently distinguish between bleeding and nonbleeding frames and perform pixel-level segmentation of bleeding areas in WCE frames. The performed experimental studies demonstrate the performance of the proposed bleeding detection method in terms of detection accuracy, where we are at least as good as the state-of-the-art approaches. In this research, we have conducted a broad comparison of a number of different state-of-the-art features and classification methods that allows building an efficient and flexible WCE video processing system.

Matched MeSH terms: Color*
The impact on patients' time-to-theatre following colour coding classification in emergency operation theatre, Sarawak General Hospital

Khaw SK, Teo SC, Bujang MA

Med J Malaysia, 2020 07;75(4):379-384.
PMID: 32723998

INTRODUCTION: A proper prioritisation system of emergency cases allows appropriate timing of surgery and efficient allocation of resources and staff expertise. The aim of this study was to determine the impact of colour coding classification on Time-to- theatre (TTT) of patients in comparison with the normal practice.
METHOD: Categorisation was a surgical judgment call after thorough clinical assessment. There were 4 levels of urgency with their respective TTT; Red (2 hours), Yellow (8 hours), Green (24 hours), Blue (72 hours). Caesarean cases were excluded in colour coding due to pre - existing classification. The data for mean TTT was collected 4 weeks before the implementation (Stage 1), and another 4 weeks after implementation (Stage II). As there was a violation in the assumption for parametric test, Mann Whitney U test was used to compare the means between these two groups. Using logarithmic (Ln) transformation for TTT, Analysis of Covariance (ANCOVA) was conducted for multivariate analysis to adjust the effect of various departments. The mean TTT for each colour coding classification was also calculated.
RESULTS: The mean TTT was reduced from 13 hours 48 min to 10 hours, although more cases were completed in Stage II (428 vs 481 cases). Based on Mann-Whitney U test, the difference in TTT for Stage I (Median=6.0, /IQR=18.9) and Stage II (Median=4.2, IQR=11.5) was significantly different (p=0.023). The result remained significant (p=0.039) even after controlled for various department in the analysis. The mean/median TTT after colour coding was Red- 2h 24min/1h, Yellow- 8h 26min/3h 45 min, Green- 15h 8min/8h 15min, and Blue- 13h 46min/13h 5min.
CONCLUSION: Colour coding classification in emergency Operation (OT) was effective in reducing TTT of patients for non-caesarean section cases.

Matched MeSH terms: Color*
The influence of age, refractive error, visual demand and lighting conditions on accommodative ability in Malay children and adults

Chen AH, Ahmad A, Kearney S, Strang N

Graefes Arch Clin Exp Ophthalmol, 2019 Sep;257(9):1997-2004.
PMID: 31273509 DOI: 10.1007/s00417-019-04405-z

PURPOSE: Near work, accommodative inaccuracy and ambient lighting conditions have all been implicated in the development of myopia. However, differences in accommodative responses with age and refractive error under different visual conditions remain unclear. This study explores differences in accommodative ability and refractive error with exposure to differing ambient illumination and visual demands in Malay schoolchildren and adults.
METHODS: Sixty young adults (21-25 years) and 60 schoolchildren (8-12 years) were recruited. Accommodative lag and accommodative fluctuations at far (6 m) and near (25 cm) were measured using the Grand Seiko WAM-5500 open-field autorefractor. The effects of mesopic room illumination on accommodation were also investigated.
RESULTS: Repeated-measures ANOVA indicated that accommodative lag at far and near differed significantly between schoolchildren and young adults [F(1.219, 35.354) = 11.857, p 0.05). Accommodative lag and fluctuations were greater under mesopic room conditions for all ages [all p

Matched MeSH terms: Color Vision/physiology*
Fulltext Euarchontan Opsin Variation Brings New Focus to Primate Origins

Melin AD, Wells K, Moritz GL, Kistler L, Orkin JD, Timm RM, et al.

Mol Biol Evol, 2016 Apr;33(4):1029-41.
PMID: 26739880 DOI: 10.1093/molbev/msv346

Debate on the adaptive origins of primates has long focused on the functional ecology of the primate visual system. For example, it is hypothesized that variable expression of short- (SWS1) and middle-to-long-wavelength sensitive (M/LWS) opsins, which confer color vision, can be used to infer ancestral activity patterns and therefore selective ecological pressures. A problem with this approach is that opsin gene variation is incompletely known in the grandorder Euarchonta, that is, the orders Scandentia (treeshrews), Dermoptera (colugos), and Primates. The ancestral state of primate color vision is therefore uncertain. Here, we report on the genes (OPN1SW and OPN1LW) that encode SWS1 and M/LWS opsins in seven species of treeshrew, including the sole nocturnal scandentian Ptilocercus lowii. In addition, we examined the opsin genes of the Central American woolly opossum (Caluromys derbianus), an enduring ecological analogue in the debate on primate origins. Our results indicate: 1) retention of ultraviolet (UV) visual sensitivity in C. derbianus and a shift from UV to blue spectral sensitivities at the base of Euarchonta; 2) ancient pseudogenization of OPN1SW in the ancestors of P. lowii, but a signature of purifying selection in those of C. derbianus; and, 3) the absence of OPN1LW polymorphism among diurnal treeshrews. These findings suggest functional variation in the color vision of nocturnal mammals and a distinctive visual ecology of early primates, perhaps one that demanded greater spatial resolution under light levels that could support cone-mediated color discrimination.

Matched MeSH terms: Color Vision/genetics*
Neural activation patterns and connectivity in visual attention during number and non-number processing: An ERP study using Ishihara pseudoisochromatic plates

Al-Marri F, Reza F, Begum T, Hitam WHW, Jin GK, Xiang J

J Integr Neurosci, 2018 Aug 15;17(3):257-269.
PMID: 30338955 DOI: 10.31083/JIN-170058

Visual cognitive function is important in the construction of executive function in daily life. Perception of visual number form (e.g. Arabic digits) and numerosity (numeric magnitude) is of interest to cognitive neuroscientists. Neural correlates and the functional measurement of number representations are complex events when their semantic categories are assimilated together with concepts of shape and color. Color perception can be processed further to modulate visual cognition. The Ishihara pseudoisochromatic plates are one of the best and most common screening tools for basic red-green color vision testing. However, there has been little study of visual cognitive function assessment using such pseudoisochromatic plates. 25 healthy normal trichromat volunteers were recruited and studied using a 128-sensor net to record event-related electroencephalogram. Subjects were asked to respond by pressing numbered buttons when they saw the number and non-number plates of the Ishihara color vision test. Amplitudes and latencies of N100 and P300 event related potential components were analyzed from 19 electrode sites in the international 10-20 system. A brain topographic map, cortical activation patterns, and Granger causation (effective connectivity) were analyzed from 128 electrode sites. No significant differences between N100 event related potential components for either stimulus indicates early selective attention processing was similar for number and non-number plate stimuli, but non-number plate stimuli evoked significantly higher amplitudes, longer latencies of the P300 event related potential component with a slower reaction time compared to number plate stimuli imply the allocation of attentional load was more in non-number plate processing. A different pattern of the asymmetric scalp voltage map was noticed for P300 components with a higher intensity in the left hemisphere for number plate tasks and higher intensity in the right hemisphere for non-number plate tasks. Asymmetric cortical activation and connectivity patterns revealed that number recognition occurred in the occipital and left frontal areas where as the consequence was limited to the occipital area during the non-number plate processing. Finally, results demonstrated that the visual recognition of numbers dissociates from the recognition of non-numbers at the level of defined neural networks. Number recognition was not only a process of visual perception and attention, but was also related to a higher level of cognitive function, that of language.

Matched MeSH terms: Color Perception; Color Vision
Fulltext Study of Visual Function in Adult Epileptic Patients on Sodium Valproate or Carbamazepine Monotherapy

Matthew TJH, Tharakan J, Tai E, Hussein A

Cureus, 2019 Apr 27;11(4):e4553.
PMID: 31275777 DOI: 10.7759/cureus.4553

Objective Epilepsy is a debilitating disease. Visual function changes have been reported and may be attributed to the epileptic changes or as a result of medication side effect. Sodium valproate and carbamazepine are both first line anti-epileptic medications used in Malaysian health care. Sodium valproate inhibits glutamate and γ-aminobutyric acid (GABA) transaminase while carbamazepine acts on the sodium channel - both are an important part of the retina. This study aimed to compare the visual functions of epilepsy patients on carbamazepine or sodium valproate monotherapy. Design A cross-sectional study was conducted at a tertiary hospital between June 2016 and November 2018. Methods Patients with idiopathic epilepsy that fulfill the inclusion and exclusion criteria were recruited from the neurology clinic. They were divided into two groups and underwent complete eye examinations. Visual functions such as color vision testing, contrast sensitivity, visual field and retinal nerve fiber layer measurement were subsequently performed. Statistical analysis was done using Statistical Package for the Social Science, version 24 (SPSS Inc, Chicago, IL, USA). Results A total of 100 patients (sodium valproate: 50 patients; carbamazepine: 50 patients) were recruited for the study. There were no statistically significant changes in anatomical or visual function between the sodium valproate and carbamazepine group. However, patients from both groups displayed color vision defect in the blue and green axes. Changes in color vision could indicate early retina toxicity secondary to the medication. Although there were no visual field changes, patients recorded a slight reduction of mean deviation. Changes of mean deviation could be attributed to the side effect of medication or the disease process. Conclusions Epileptic patients taking sodium valproate or carbamazepine did not demonstrate statistically significant change in visual function.

Matched MeSH terms: Color Vision Defects; Color Vision

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