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Fulltext Compositional analyses of white, brown and germinated forms of popular Malaysian rice to offer insight into the growing diet-related diseases

Abubakar B, Yakasai HM, Zawawi N, Ismail M

J Food Drug Anal, 2018 04;26(2):706-715.
PMID: 29567241 DOI: 10.1016/j.jfda.2017.06.010

Diet-related metabolic diseases, and especially obesity, are metabolic disorders with multifactorial aetiologies. Diet has been a cornerstone in both the aetiology and management of this metabolic disorders. Rice, a staple food for over half of the world's population, could be exploited as part of the solution to check this menace which has been skyrocketing in the last decade. The present study investigated nine forms of rice from three widely grown Malaysian rice cultivars for in vitro and in vivo (glycaemic index and load) properties that could translate clinically into a lower predisposition to diet-related diseases. The germinated brown forms of MRQ 74 and MR 84 rice cultivars had high amylose content percentages (25.7% and 25.0%), high relative percentage antioxidant scavenging abilities of 85.0% and 91.7%, relatively low glycaemic indices (67.6 and 64.3) and glycaemic load (32.3 and 30.1) values, and modest glucose uptake capabilities of 33.69% and 31.25%, respectively. The results show that all things being equal, rice cultivars that are germinated and high in amylose content when compared to their white and low amylose counterparts could translate into a lower predisposition to diet-related diseases from the dietary point of view in individuals who consume this cereal as a staple food.
Sudden Bilateral Sensorineural Hearing Loss Secondary to Cerebral Venous Thrombosis

Ishak MN, Nik-Abdul-Ghani NM, Mohamad I

Iran J Otorhinolaryngol, 2018 Mar;30(97):113-116.
PMID: 29594079

Introduction: Sudden sensorineural hearing loss (SSNHL) is an important otological emergency. Up to 90% of the cases are idiopathic. Cerebral venous thrombosis (CVT) is an extremely rare identifiable cause as it only represents 0.5% of all strokes.
Case Report: In this paper, an unusual case of bilateral SSNHL secondary to bilateral CVT with rapid and complete recovery is reported. The patient presented with sudden bilateral hearing loss associated with some neurological symptoms. Initial computed tomography (CT) venography revealed a CVT of bilateral transverse sinuses. The patient was started on an anticoagulant and imaging was repeated after five days, revealing the absence of the thrombosis. Serial pure tone audiometry (PTA) showed complete recovery of bilateral hearing within 10 days.
Conclusion: Early detection and intervention may fasten hearing recovery and improve the quality of life. The immediate restoration of venous blood flow and intracranial pressure may lead to the complete recovery of bilateral hearing loss.
Finite element analysis of the wrist in stroke patients: the effects of hand grip

Ramlee MH, Beng GK, Bajuri N, Abdul Kadir MR

Med Biol Eng Comput, 2018 Jul;56(7):1161-1171.
PMID: 29209961 DOI: 10.1007/s11517-017-1762-3

The provision of the most suitable rehabilitation treatment for stroke patient remains an ongoing challenge for clinicians. Fully understanding the pathomechanics of the upper limb will allow doctors to assist patients with physiotherapy treatment that will aid in full arm recovery. A biomechanical study was therefore conducted using the finite element (FE) method. A three-dimensional (3D) model of the human wrist was reconstructed using computed tomography (CT)-scanned images. A stroke model was constructed based on pathological problems, i.e. bone density reductions, cartilage wane, and spasticity. The cartilages were reconstructed as per the articulation shapes in the joint, while the ligaments were modelled using linear links. The hand grip condition was mimicked, and the resulting biomechanical characteristics of the stroke and healthy models were compared. Due to the lower thickness of the cartilages, the stroke model reported a higher contact pressure (305 MPa), specifically at the MC1-trapezium. Contrarily, a healthy model reported a contact pressure of 228 MPa. In the context of wrist extension and displacement, the stroke model (0.68° and 5.54 mm, respectively) reported a lower magnitude than the healthy model (0.98° and 9.43 mm, respectively), which agrees with previously reported works. It was therefore concluded that clinicians should take extra care in rehabilitation treatment of wrist movement in order to prevent the occurrence of other complications. Graphical abstract ᅟ.
Fulltext Improved In Vivo Efficacy of Anti-Hypertensive Biopeptides Encapsulated in Chitosan Nanoparticles Fabricated by Ionotropic Gelation on Spontaneously Hypertensive Rats

Auwal SM, Zarei M, Tan CP, Basri M, Saari N

Nanomaterials (Basel), 2017 Dec 02;7(12).
PMID: 29207480 DOI: 10.3390/nano7120421

Recent biotechnological advances in the food industry have led to the enzymatic production of angiotensin I-converting enzyme (ACE)-inhibitory biopeptides with a strong blood pressure lowering effect from different food proteins. However, the safe oral administration of biopeptides is impeded by their enzymatic degradation due to gastrointestinal digestion. Consequently, nanoparticle (NP)-based delivery systems are used to overcome these gastrointestinal barriers to maintain the improved bioavailability and efficacy of the encapsulated biopeptides. In the present study, the ACE-inhibitory biopeptides were generated from stone fish (Actinopyga lecanora) protein using bromelain and stabilized by their encapsulation in chitosan (chit) nanoparticles (NPs). The nanoparticles were characterized for in vitro physicochemical properties and their antihypertensive effect was then evaluated on spontaneously hypertensive rats (SHRs). The results of a physicochemical characterization showed a small particle size of 162.70 nm, a polydispersity index (pdi) value of 0.28, a zeta potential of 48.78 mV, a high encapsulation efficiency of 75.36%, a high melting temperature of 146.78 °C and an in vitro sustained release of the biopeptides. The results of the in vivo efficacy indicated a dose-dependent blood pressure lowering effect of the biopeptide-loaded nanoparticles that was significantly higher (p < 0.05) compared with the un-encapsulated biopeptides. Moreover, the results of a morphological examination using transmission electron microscopy (TEM) demonstrated the nanoparticles as homogenous and spherical. Thus, the ACE-inhibitory biopeptides stabilized by chitosan nanoparticles can effectively reduce blood pressure for an extended period of time in hypertensive individuals.
Seroprevalence of lymphatic filariasis among migrant workers in Peninsular Malaysia

Noordin R, Mohd Zain SN, Yunus MH, Sahimin N

Trans R Soc Trop Med Hyg, 2017 08 01;111(8):370-372.
PMID: 29206992 DOI: 10.1093/trstmh/trx062

Background: Malaysia aims to eliminate lymphatic filariasis (LF) by the year 2020, thus the potential threat of LF from migrant workers needs to be investigated.
Methods: Brugian and bancroftian filariasis among 484 migrant workers from six countries were investigated using rapid tests based on detection of specific IgG4 antibodies against BmR1 (Brugia Rapid) and BmSXP recombinant antigens.
Results: The seroprevalence of brugian filariasis was very low; however, bancroftian filariasis was notable among workers from India, Nepal and Myanmar.
Conclusion: Malaysia is not endemic for Wuchereria bancrofti, but harbors the vectors for the parasite, thus the results showed that migrant workers should be monitored for this infection.
Fulltext Potential loss of revenue due to errors in clinical coding during the implementation of the Malaysia diagnosis related group (MY-DRG®) Casemix system in a teaching hospital in Malaysia

Zafirah SA, Nur AM, Puteh SEW, Aljunid SM

BMC Health Serv Res, 2018 01 25;18(1):38.
PMID: 29370785 DOI: 10.1186/s12913-018-2843-1

BACKGROUND: The accuracy of clinical coding is crucial in the assignment of Diagnosis Related Groups (DRGs) codes, especially if the hospital is using Casemix System as a tool for resource allocations and efficiency monitoring. The aim of this study was to estimate the potential loss of income due to an error in clinical coding during the implementation of the Malaysia Diagnosis Related Group (MY-DRG®) Casemix System in a teaching hospital in Malaysia.

METHODS: Four hundred and sixty-four (464) coded medical records were selected, re-examined and re-coded by an independent senior coder (ISC). This ISC re-examined and re-coded the error code that was originally entered by the hospital coders. The pre- and post-coding results were compared, and if there was any disagreement, the codes by the ISC were considered the accurate codes. The cases were then re-grouped using a MY-DRG® grouper to assess and compare the changes in the DRG assignment and the hospital tariff assignment. The outcomes were then verified by a casemix expert.

RESULTS: Coding errors were found in 89.4% (415/424) of the selected patient medical records. Coding errors in secondary diagnoses were the highest, at 81.3% (377/464), followed by secondary procedures at 58.2% (270/464), principal procedures of 50.9% (236/464) and primary diagnoses at 49.8% (231/464), respectively. The coding errors resulted in the assignment of different MY-DRG® codes in 74.0% (307/415) of the cases. From this result, 52.1% (160/307) of the cases had a lower assigned hospital tariff. In total, the potential loss of income due to changes in the assignment of the MY-DRG® code was RM654,303.91.

CONCLUSIONS: The quality of coding is a crucial aspect in implementing casemix systems. Intensive re-training and the close monitoring of coder performance in the hospital should be performed to prevent the potential loss of hospital income.
Oxindole based oxadiazole hybrid analogs: Novel α-glucosidase inhibitors

Taha M, Imran S, Rahim F, Wadood A, Khan KM

Bioorg Chem, 2018 02;76:273-280.
PMID: 29223804 DOI: 10.1016/j.bioorg.2017.12.001

Inhibition of α-glucosidase is an effective strategy for controlling post-prandial hyperglycemia in diabetic patients. Beside these α-glucosidase inhibitors has been also used as anti-obesity and anti-viral drugs. Keeping in view the greater importance of α-glucosidase inhibitors here in this study we are presenting oxindole based oxadiazoles hybrid analogs (1-20) synthesis, characterized by different spectroscopic techniques including 1H NMR and EI-MS and their α-glucosidase inhibitory activity. All compounds were found potent inhibitors for the enzyme with IC50 values ranging between 1.25 ± 0.05 and 268.36 ± 4.22 µM when compared with the standard drug acarbose having IC50 value 895.09 ± 2.04 µM. Our study identifies novel series of potent α-glucosidase inhibitors and further investigation on this may led to the lead compounds. A structure activity relationship has been established for all compounds. The interactions of the active compounds and enzyme active site were established with the help of molecular docking studies.
Fulltext Response Surface Optimisation for the Production of Antioxidant Hydrolysates from Stone Fish Protein Using Bromelain

Auwal SM, Zarei M, Abdul-Hamid A, Saari N

Evid Based Complement Alternat Med, 2017;2017:4765463.
PMID: 29234403 DOI: 10.1155/2017/4765463

Protein hydrolysates produced from different food sources exhibit therapeutic potential and can be used in the management of chronic diseases. This study was targeted to optimise the conditions for the hydrolysis of stone fish protein to produce antioxidant hydrolysates using central composite design (CCD) by response surface methodology (RSM). The stone fish protein was hydrolysed under the optimum predicted conditions defined by pH (6.5), temperature (54°C), E/S ratio (1.5%), and hydrolysis time (360 min). The hydrolysates were then evaluated for 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging activity and ferrous ion- (Fe2+-) chelating activity. Results validation showed no significant difference between the experimental values of DPPH• scavenging activity (48.94%) and Fe2+-chelating activity (25.12%) obtained at 54.62% degree of hydrolysis (DH) compared to their corresponding predicted values of 49.79% and 24.08% at 53.08% DH, respectively. The hydrolysates demonstrated non-Newtonian behavior (n < 1) with stronger shear-thinning effect and higher viscosities at increasing concentration. Thus, RSM can be considered as a promising strategy to optimise the production of stone fish protein hydrolysates containing antioxidant peptides. It is hoped that this finding will enhance the potential of stone fish protein hydrolysates (SHs) as therapeutic bioactive ingredient in functional foods development.
The fate and transport of arsenic species in the aquatic ecosystem: a case study on Bestari Jaya, Peninsular Malaysia

Mana SCA, Fatt NT, Ashraf MA

Environ Sci Pollut Res Int, 2017 Oct;24(29):22799-22807.
PMID: 27987120 DOI: 10.1007/s11356-016-8195-7

The field of arsenic pollution research has grown rapidly in recent years. Arsenic constitutes a broad range of elements from the Earth's crust and is released into the environment from both anthropogenic and natural sources due to its relative mobility under different redox conditions. The toxicity of arsenic is described in its inorganic form, as inorganic arsenic compounds can leach into different environments. Sampling was carried out in the Bestari Jaya catchment while using a land use map to locate the site, and experiments were conducted via sequential extraction and inductively coupled plasma optical emission spectroscopy to quantify proportions of arsenic in the sediment samples. The results show that metals in sediments of nonresidual fractions, which are more likely to be likely released into aquatic environments, are more plentiful than the residual sediment fractions. These findings support the mobility of heavy metals and especially arsenic through sediment layers, which can facilitate remediation in environments heavily polluted with heavy metals.
Fulltext Chronic Viral Hepatitis in Malaysia: "Where are we now?"

Raihan R, Mohamed R, Radzi Abu Hassan M, Md Said R

Euroasian J Hepatogastroenterol, 2017 Jan-Jun;7(1):65-67.
PMID: 29201775 DOI: 10.5005/jp-journals-10018-1214

Malaysia is a country where an estimated 1 million people are chronically infected with hepatitis B virus (HBV) and an estimated 2.5% of the adult population are positive for antibody to hepatitis C virus (HCV). Effective nationwide vaccine coverage seems to be a highly effective measure to prevent new HBV infection. Treatment of HCV infection is also a regular practice in Malaysia. These measures highlight the possibility to reach the World Health Organization elimination target by 2030. To achieve this target, the Health Ministry and other nongovernmental organizations, such as My Commitment to Cure (MyC2C) are working together to develop a strategic road map to reach the global elimination target in Malaysia by 2030. How to cite this article: Raihan R, Mohamed R, Hasan MRA, Rosaida MS. Chronic Viral Hepatitis in Malaysia: "Where are we now?" Euroasian J Hepato-Gastroenterol 2017;7(1):65-67.
A new sulphated flavone and other phytoconstituents from the leaves of Tetracera indica Merr. and their alpha-glucosidase inhibitory activity

Alhassan AM, Ahmed QU, Latip J, Shah SAA

Nat Prod Res, 2019 Jan;33(1):1-8.
PMID: 29417849 DOI: 10.1080/14786419.2018.1437427

The bioactivity guided fractionation of Tetracera indica leaves crude ethanolic extract has afforded the isolation and characterization of six compounds including a new natural product viz., 5,7-dihydroxyflavone-O-8-sulphate (1) and five known flavonoids (2-6). The structures of the compounds were elucidated using 1D and 2D NMR and HRESIMS spectroscopic analyses. All the isolated compounds were evaluated for their in vitro inhibitory activity against alpha-glucosidase. Compound 1, 5 and 6 showed strong alpha-glucosidase inhibitory activity, 3 and 4 displayed weak activity while compound 2 was inactive. The interactions of the active compounds with alpha-glucosidase were further investigated using molecular docking to confirm their antidiabetic potential.
Fulltext Towards Efficient Wireless Body Area Network Using Two-Way Relay Cooperation

Waheed M, Ahmad R, Ahmed W, Drieberg M, Alam MM

Sensors (Basel), 2018 Feb 13;18(2).
PMID: 29438278 DOI: 10.3390/s18020565

The fabrication of lightweight, ultra-thin, low power and intelligent body-borne sensors leads to novel advances in wireless body area networks (WBANs). Depending on the placement of the nodes, it is characterized as in/on body WBAN; thus, the channel is largely affected by body posture, clothing, muscle movement, body temperature and climatic conditions. The energy resources are limited and it is not feasible to replace the sensor's battery frequently. In order to keep the sensor in working condition, the channel resources should be reserved. The lifetime of the sensor is very crucial and it highly depends on transmission among sensor nodes and energy consumption. The reliability and energy efficiency in WBAN applications play a vital role. In this paper, the analytical expressions for energy efficiency (EE) and packet error rate (PER) are formulated for two-way relay cooperative communication. The results depict better reliability and efficiency compared to direct and one-way relay communication. The effective performance range of direct vs. cooperative communication is separated by a threshold distance. Based on EE calculations, an optimal packet size is observed that provides maximum efficiency over a certain link length. A smart and energy efficient system is articulated that utilizes all three communication modes, namely direct, one-way relay and two-way relay, as the direct link performs better for a certain range, but the cooperative communication gives better results for increased distance in terms of EE. The efficacy of the proposed hybrid scheme is also demonstrated over a practical quasi-static channel. Furthermore, link length extension and diversity is achieved by joint network-channel (JNC) coding the cooperative link.
The Clinimetric Properties of Instruments Measuring Home Hazards for Older People at Risk of Falling: A Systematic Review

Romli MH, Mackenzie L, Lovarini M, Tan MP, Clemson L

Eval Health Prof, 2018 03;41(1):82-128.
PMID: 29415567 DOI: 10.1177/0163278716684166

Home hazards are associated with falls among older people living in the community. However, evaluating home hazards is a complex process as environmental factors vary according to geography, culture, and architectural design. As a result, many health practitioners commonly use nonstandardized assessment methods that may lead to inaccurate findings. Thus, the aim of this systematic review was to identify standardized instruments for evaluating home hazards related to falls and evaluate the clinimetric properties of these instruments for use by health practitioners. A systematic search was conducted in the Medline, CINAHL, AgeLine, Web of Science databases, and the University of Sydney Library CrossSearch Engine. Study screening, assessment, and quality ratings were conducted independently. Thirty-six studies were identified describing 19 instruments and three assessment techniques. The clinimetric properties varied between instruments. The Home Falls and Accidents Screening Tool, Home Safety Self-Assessment Tool, In-Home Occupational Performance Evaluation, and Westmead Home Safety Assessment were the instruments with high potential for evaluating home hazards associated with falls. Health practitioners can choose the most appropriate instruments for their practice, as a range of standardized instruments with established clinimetric properties are available.
Fulltext A Lateral Flow Rapid Test for Human Toxocariasis Developed Using Three Toxocara canis Recombinant Antigens

Yunus MH, Tan Farrizam SN, Abdul Karim IZ, Noordin R

Am J Trop Med Hyg, 2018 Jan;98(1):32-38.
PMID: 29141740 DOI: 10.4269/ajtmh.17-0632

Laboratory diagnosis of toxocariasis is still a challenge especially in developing endemic countries with polyparasitism. In this study, three Toxocara canis recombinant antigens, rTES-26, rTES-30, and rTES-120, were expressed and used to prepare lateral flow immunoglobulin G4 (IgG4) dipsticks. The concordance of the results of the rapid test (comprising three dipsticks) with a commercial IgG-enzyme-linked immunosorbent assay (ELISA) (Cypress Diagnostics, Belgium) was compared against the concordance of two other commercial IgG-ELISA kits (Bordier, Switzerland and NovaTec, Germany) with the Cypress kit. Using Toxocara-positive samples, the concordance of the dipstick dotted with rTES-26, rTES-30, and rTES-120 was 41.4% (12/29), 51.7% (15/29), and 72.4% (21/29), respectively. When positivity with any dipstick was considered as an overall positive rapid test result, the concordance with the Cypress kit was 93% (27/29). Meanwhile, when compared with the results of the Cypress kit, the concordance of IgG-ELISA from NovaTec and Bordier was 100% (29/29) and 89.7% (26/29), respectively. Specific IgG4 has been recognized as a marker of active infection for several helminthic diseases; therefore, the two non-concordant results of the rapid test when compared with the NovaTec IgG-ELISA kit may be from samples of people with non-active infection. All the three dipsticks showed 100% (50/50) concordance with the Cypress kit when tested with serum from individuals who were healthy and with other infections. In conclusion, the lateral flow rapid test is potentially a good, fast, and easy test for toxocariasis. Next, further validation studies and development of a test with the three antigens in one dipstick will be performed.
Analysis of Nutritional Traits and Aflatoxin Contamination in Selected Maize Varieties from Pakistan

Majeed S, Iqbal M, Asi MR, Iqbal SZ, Selamat J

J Food Prot, 2017 Dec;80(12):1993-1998.
PMID: 29131682 DOI: 10.4315/0362-028X.JFP-17-117

Recently, cultivation of high-yielding hybrid maize varieties has revolutionized maize production in Pakistan. Analyses of nutritional traits and aflatoxin (AF) contamination in these varieties can aid in the identification of susceptible and resistant varieties, particularly for cultivation in the Pakistani agro-climatic environment. Five spring maize varieties-Pioneer, Neelam, DK-919, Desi, and Hi-maize-were selected for analyses of their nutritional, tocopherol, and AF contents. Protein, carbohydrate, oil, ash, fiber, and moisture contents ranged between 8.7 and 10.8%, 68 and 71%, 3.72 and 5.56%, 1.09 and 1.81%, 1.1 and 3.1%, and 11.7 and 14.2%, respectively. Tocopherol levels in selected varieties were in the range of 461 to 1,430 μg/g. Hi-maize exhibited significantly higher protein and tocopherol contents than the other varieties, indicating its better suitability for feed and silage applications. The highest mean level of total AFs, 14.5 ± 0.12 μg/kg, was found in Desi, and results showed that the most dominant AF found in the maize varieties was AFB1. Furthermore, the results showed that the higher the level of tocopherol, the lower the concentration of total AFs and vice versa in maize varieties. The results can be used to investigate additional susceptible maize varieties that are resistant to fungal attack.
Fulltext Evaluation of sticky traps for adult Aedes mosquitoes in Malaysia: a potential monitoring and surveillance tool for the efficacy of control strategies

Roslan MA, Ngui R, Vythilingam I, Sulaiman WYW

J Vector Ecol, 2017 12;42(2):298-307.
PMID: 29125255 DOI: 10.1111/jvec.12270

The present study compared the performance of sticky traps in order to identify the most effective and practical trap for capturing Aedes aegypti and Aedes albopictus mosquitoes. Three phases were conducted in the study, with Phase 1 evaluating the five prototypes (Models A, B, C, D, and E) of sticky trap release-and-recapture using two groups of mosquito release numbers (five and 50) that were released in each replicate. Similarly, Phase 2 compared the performance between Model E and the classical ovitrap that had been modified (sticky ovitrap), using five and 50 mosquito release numbers. Further assessment of both traps was carried out in Phase 3, in which both traps were installed in nine sampling grids. Results from Phase 1 showed that Model E was the trap that recaptured higher numbers of mosquitoes when compared to Models A, B, C, and D. Further assessment between Model E and the modified sticky ovitrap (known as Model F) found that Model F outperformed Model E in both Phases 2 and 3. Thus, Model F was selected as the most effective and practical sticky trap, which could serve as an alternative tool for monitoring and controlling dengue vectors in Malaysia.
Fulltext Morphological Characteristics and Habitats of Red Seaweed Gracilaria spp. (Gracilariaceae, Rhodophyta) in Santubong and Asajaya, Sarawak, Malaysia

Othman MNA, Hassan R, Harith MN, Sah ASRM

Trop Life Sci Res, 2018 Mar;29(1):87-101.
PMID: 29644017 MyJurnal DOI: 10.21315/tlsr2018.29.1.6

Red seaweed Gracilaria, one of the largest genus in Division Rhodophyta inhabits Sarawak coastal water. This study was designed to identify the species of Gracilaria using morphological approach and to assess selected water quality parameters in Gracilaria habitats. Three field samplings were carried out in Santubong and Asajaya, Sarawak from November 2013 to December 2014. Overall, three species were identified namely Gracilaria changii, G. blodgettii and G. coronopifolia, attached to net of cage culture in Santubong and root of mangrove trees in Asajaya. In addition, three different taxa of aquatic macroinvertebrates (polychaete, small crab, bivalve) and single species of red seaweed (Acanthophora sp.) were observed in Gracilaria assemblages. An estimate of 37% to 40% of the upper part of the cage net in Santubong was covered by seaweeds and only 16% to 20% in Asajaya's mangrove. The study had provided better information on identification of Gracilaria and their habitat in Sarawak. Future work involving DNA barcoding of each species is in progress.
Fulltext Effects of Size and Aggregation/Agglomeration of Nanoparticles on the Interfacial/Interphase Properties and Tensile Strength of Polymer Nanocomposites

Ashraf MA, Peng W, Zare Y, Rhee KY

Nanoscale Res Lett, 2018 Jul 17;13(1):214.
PMID: 30019092 DOI: 10.1186/s11671-018-2624-0

In this study, several simple equations are suggested to investigate the effects of size and density on the number, surface area, stiffening efficiency, and specific surface area of nanoparticles in polymer nanocomposites. In addition, the roles of nanoparticle size and interphase thickness in the interfacial/interphase properties and tensile strength of nanocomposites are explained by various equations. The aggregates/agglomerates of nanoparticles are also assumed as large particles in nanocomposites, and their influences on the nanoparticle characteristics, interface/interphase properties, and tensile strength are discussed. The small size advantageously affects the number, surface area, stiffening efficiency, and specific surface area of nanoparticles. Only 2 g of isolated and well-dispersed nanoparticles with radius of 10 nm (R = 10 nm) and density of 2 g/cm3 produce the significant interfacial area of 250 m2 with polymer matrix. Moreover, only a thick interphase cannot produce high interfacial/interphase parameters and significant mechanical properties in nanocomposites because the filler size and aggregates/agglomerates also control these terms. It is found that a thick interphase (t = 25 nm) surrounding the big nanoparticles (R = 50 nm) only improves the B interphase parameter to about 4, while B = 13 is obtained by the smallest nanoparticles and the thickest interphase.
Fulltext Cytotoxic effects of Benzodioxane, Naphthalene diimide, Porphyrin and Acetamol derivatives on HeLa cells

Jeyamogan S, Khan NA, Anwar A, Shah MR, Siddiqui R

SAGE Open Med, 2018;6:2050312118781962.
PMID: 30034805 DOI: 10.1177/2050312118781962

Objectives: To synthesize novel compounds belonging to Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrin classes and test their potential anticancer properties.
Methods: Several compounds were synthesized and their molecular identity was confirmed using nuclear magnetic resonance. Potential anticancer properties were determined using cytopathogenicity assays and growth inhibition assays using cervical cancer cells (HeLa). Cells were incubated with different concentrations of compounds belonging to Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrins and effects were determined. HeLa cells cytopathogenicity was determined by measuring lactate dehydrogenase release using cytotoxicity detection assay. Growth inhibition assays were performed by incubating 50% semi-confluent HeLa cells with Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrin compounds and HeLa cell proliferation was observed. Growth inhibition and host cell death were compared in the presence and absence of drugs.
Results: Cytopathogenicity assays showed that the selected compounds were cytotoxic against HeLa cells, killing up to 90% of cells. Growth inhibition assays exhibited 100% growth inhibition. These effects are likely via oxidative stress, production of reactive oxygen species, changes in cytosolic and intracellular calcium/adenine nucleotide homeostasis, inhibition of ribonucleotide reductase/cyclooxygenase and/or glutathione depletion.
Conclusions: Benzodioxane, Naphthalene diimide, Aminophenol derivatives and Porphyrins exhibited potent anticancer properties. These findings are promising and should pave the way in the rationale development of anticancer drugs. Using different cancer cell lines, future studies will determine their potential as anti-tumour agents as well as their precise molecular mode of action.
Rheological behavior of biodegradable N-succinyl chitosan-g-poly (acrylic acid) hydrogels and their applications as drug carrier and in vitro theophylline release

Bashir S, Teo YY, Ramesh S, Ramesh K, Mushtaq MW

Int J Biol Macromol, 2018 Oct 01;117:454-466.
PMID: 29807081 DOI: 10.1016/j.ijbiomac.2018.05.182

Novel pH sensitive N-succinyl chitosan-g-poly (acrylic acid) hydrogels were synthesized through free radical mechanism. Rheometer was used to observe the mechanical strength of the hydrogels. In vitro degradation was conducted in SIF (pH 7.4). The effect of concentration of monomers, initiator, and crosslinking agent and pH and ionic strength of NaCl, CaCl2, and AlCl3 on swelling of the hydrogels was observed. The results showed that equilibrium swelling ratio was highly influenced by concentration of monomers, initiator, and crosslinking agent concentration, and pH and salt solutions of NaCl, CaCl2, and AlCl3. The swelling kinetics revealed that swelling followed non-Fickian anomalous transport. Furthermore, theophylline loading (DL %) and encapsulation efficiency (EE %) of the hydrogels was in the range of 15.5 ± 0.15-22.8 ± 0.06% and 62 ± 0.15-91 ± 0.26%, respectively. The release of theophylline in physiological mediums was strongly influenced by the pH. The theophylline release was in the range of 51 ± 0.20-92 ± 0.12% in SIF and 7.4 ± 0.02-14.9 ± 0.03% in SGF (pH 1.2), respectively. The release data fitted well to Korsmeyer-Peppas model. The chemical activity of the theophylline suggested that drug maintained its chemical activity after release in vitro. The results suggest that synthesized hydrogels are excellent drug carriers.

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