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Fulltext Prevalence of Frailty and Its Standardised Assessment Tools among Malaysian Older Person: A Systematic Review

Shaharudin MI, Abd Rahman NFN

Malays J Med Sci, 2022 Dec;29(6):34-45.
PMID: 36818895 DOI: 10.21315/mjms2022.29.6.4

Frailty is conceptually defined as a state of increased vulnerability in older persons, resulting from age-associated declines in physiological reserve and function as they cope with everyday life stressors. To date, the prevalence of frailty has been assessed in various ways. The objective of this study was to identify the prevalence of the condition and the assessment tools used to determine its occurrence among Malaysian older individuals. A systematic literature search was performed on electronic bibliographic databases, namely, Web of Science, Scopus, EBSCOHost: MEDLINE Complete and Google Scholar. Ten eligible articles were reviewed and evaluated using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Newcastle-Ottawa Scale. Frailty was diagnosed using Fried's frailty phenotype and the Groningen Frailty Indicator (GFI). Assessment tools that included physical performance tests detected a lower prevalence of frailty than that determined using questionnaire-based tools. The prevalence of frailty ranged from as low as 6% to as high as 76%, and there was a higher prevalence among older persons living in aged care homes. This review suggests increasing prospective and interventional studies on frailty to establish a cause-effect relationship between standardised tools of assessing frailty and its prevalence among Malaysian older persons and provide guidelines for health professionals on promoting active lifestyles among older populations.
AN OUTBREAK OF TETRODOTOXIN POISONING FROM CONSUMING HORSESHOE CRABS IN SABAH

Suleiman M, Muhammad J, Jelip J, William T, Chua TH

Southeast Asian J Trop Med Public Health, 2017 Jan;48(1):197-203.
PMID: 29644840

The horseshoe crab (Carcinoscorpius rotundicauda) is consumed by those
residing near the coastal areas of Kota Marudu District in Malaysia, as it is considered
a delicacy. During June to August, 2011 thirty cases of tetrodotoxin poisoning
were reported from Kota Marudu District following ingestion of horseshoe
crabs caught in Kota Marudu Bay. The purpose of this study is to describe this
case series in order to determine risk factors to prevent further outbreaks. There
were six confirmed and 24 probable cases of tetrodotoxin poisoning identified in
the study area during the study period as diagnosed by clinical presentation and
laboratory findings. Symptoms included dizziness (80%), circumoral and lingual
numbness (80%), hand and feet numbness (63.3%), nausea and vomiting (30%)
and weakness and difficulty in breathing (26.6%). Three cases (10%) died while 27
cases recovered. Forty-seven percent of the cases had onset of symptoms within
30 minutes of ingestion and 14% 31-60 minutes after ingestion of horseshoe crab
meat. Urine samples were collected from the cases, while horseshoe crabs, cockles
and sea water from the epidemic area were also taken for analysis. Tetrodotoxin
was detected in the urine of six cases; the highest concentrations recorded were
among the three cases who died. High tetrodotoxin concentrations were found
in the hepatic cecum and eggs of the tested horseshoe crabs. Dinoflagellates were
not detected in the sea water or cockle samples. Intensive health education was
initiated quickly to stop other members of the Marudu Bay community from
consuming the horseshoe crabs. This is the first documented epidemic of tetrodotoxin
poisoning in Sabah.
Fulltext Modulation of NFκB signalling pathway by tocotrienol: A systematic review

Nasir NAA, Sadikan MZ, Agarwal R

Asia Pac J Clin Nutr, 2021 Sep;30(3):537-555.
PMID: 34587713 DOI: 10.6133/apjcn.202109_30(3).0020

Tocotrienols have been reported to exert anticancer, anti-inflammatory, antioxidant, cardio-protective and boneprotective effects through modulation of NFκB signalling pathway. The objective of this systematic review is to evaluate available literature showing the effect of tocotrienols on NFκB signalling pathway and identify the potential mechanisms involved. A comprehensive search was conducted using PubMed and SCOPUS databases using the keywords "tocotrienol" and "NFκB" or "nuclear factor kappa b". Main inclusion criteria were English language original articles showing the effect of tocotrienol on NFκB signalling pathway. Fifty-nine articles were selected from the total of 117 articles initially retrieved from the literature search. Modulation of regulatory proteins and genes such as inhibition of farnesyl prenyl transferase were found to be the mechanisms underlying the tocotrienol-induced suppression of NFκB activation.
Fulltext Outcomes of Renal Transplantation in Brunei Darussalam over a Twenty-Year Period (1993-2012)

Tan J, Khalil MA, Tan SY, Khalil M, Ahmed D, Zinna S, et al.

J Transplant, 2014;2014:784805.
PMID: 25478205 DOI: 10.1155/2014/784805

Objectives. Brunei Darussalam has a high prevalence and incidence of end stage renal disease (ESRD). Up until 2012, all renal transplantations were performed in overseas centres, either as government-sponsored (living-related transplantation) or as self-sponsored (commercialized transplantation) ones. We hypothesize that graft and patient survival of Brunei renal transplant patients are on a par with international standards. Materials and Methods. Data of all renal transplant patients in Brunei were analysed over a twenty-year period from registry records and case notes. Comparative survival data from other countries were obtained from PubMed-listed literature. Results. A total of 49 transplantation procedures were performed in foreign centres between 1993 and 2012. 29 were government-sponsored and 20 were self-sponsored transplantations. The 5- and 10-year overall patient survival rates were 93.3% and 90.1%, respectively. The 5- and 10-year overall graft survival rates were 91.1% and 81.2%. There is no difference in the survival outcomes of government-sponsored and self-sponsored patients. Living-related (government-sponsored) and commercialised (self-sponsored) grafts had equivalent survival to those reported in the literature. Conclusion. Our survival data was on par with those achieved in many countries. We hope to use this information to convince local stakeholders and patients to favour transplantation as the preferred modality of RRT.
Fulltext Multivariate analysis of factors affecting presence and/or agenesis of third molar tooth

Alam MK, Hamza MA, Khafiz MA, Rahman SA, Shaari R, Hassan A

PLoS One, 2014;9(6):e101157.
PMID: 24967595 DOI: 10.1371/journal.pone.0101157

To investigate the presence and/or agenesis of third molar (M3) tooth germs in orthodontics patients in Malaysian Malay and Chinese population and evaluate the relationship between presence and/or agenesis of M3 with different skeletal malocclusion patterns and sagittal maxillomandibular jaw dimensions. Pretreatment records of 300 orthodontic patients (140 males and 160 females, 219 Malaysian Malay and 81 Chinese, average age was 16.27±4.59) were used. Third-molar agenesis was calculated with respect to race, genders, number of missing teeth, jaws, skeletal malocclusion patterns and sagittal maxillomandibular jaw dimensions. The Pearson chi-square test and ANOVA was performed to determine potential differences. Associations between various factors and M3 presence/agenesis groups were assessed using logistic regression analysis. The percentages of subjects with 1 or more M3 agenesis were 30%, 33% and 31% in the Malaysian Malay, Chinese and total population, respectively. Overall prevalence of M3 agenesis in male and female was equal (P>0.05). The frequency of the agenesis of M3s is greater in maxilla as well in the right side (P>0.05). The prevalence of M3 agenesis in those with a Class III and Class II malocclusion was relatively higher in Malaysian Malay and Malaysian Chinese population respectively. Using stepwise regression analyses, significant associations were found between Mx (P<0.05) and ANB (P<0.05) and M3 agenesis. This multivariate analysis suggested that Mx and ANB were significantly correlated with the M3 presence/agenesis.
Fulltext Synthesis, Structural Characterization, and Evaluation of the Biological Properties of Heteroleptic Palladium(II) Complexes

Khan H, Daraz N, Khan MN, Said M, Akhtar N, Badshah A, et al.

Bioinorg Chem Appl, 2014;2014:916361.
PMID: 25276113 DOI: 10.1155/2014/916361

Five heteroleptic palladium(II) complexes of the general formula Pd(PR3)(tu)Cl2, where PR3 = triphenylphosphine (1), diphenyl-o-tolylphosphine (2), diphenyl-p-tolylphosphine (3), diphenyl-t-butylphosphine (4), and diphenyl-o-methoxyphenylphosphine (5), and tu = 1,3-bis(2-methoxyphenyl) thiourea. They all have been synthesized and characterized by various spectroscopic techniques (elemental analysis, FTIR, and (1)H NMR and the ligand 1,3-bis(2-methoxyphenyl) thiourea was synthesized by single crystal X-ray diffraction technique). The synthesized compounds were screened for their antibacterial activity against four strains of bacteria (Escherichia coli, Shigella flexneri, Staphylococcus aureus, and Bacillus subtilis). The antitumor potential was evaluated in terms of activity against brine shrimp eggs and DNA interaction. The mixed ligand complexes have exhibited moderate antibacterial activity and promising antitumor potential.
Synthesis of α, β-unsaturated carbonyl based compounds as acetylcholinesterase and butyrylcholinesterase inhibitors: characterization, molecular modeling, QSAR studies and effect against amyloid β-induced cytotoxicity

Bukhari SN, Jantan I, Masand VH, Mahajan DT, Sher M, Naeem-ul-Hassan M, et al.

Eur J Med Chem, 2014 Aug 18;83:355-65.
PMID: 24980117 DOI: 10.1016/j.ejmech.2014.06.034

A series of novel carbonyl compounds was synthesized by a simple, eco-friendly and efficient method. These compounds were screened for anti-oxidant activity, in vitro cytotoxicity and for inhibitory activity for acetylcholinesterase and butyrylcholinesterase. The effect of these compounds against amyloid β-induced cytotoxicity was also investigated. Among them, compound 14 exhibited strong free radical scavenging activity (18.39 μM) while six compounds (1, 3, 4, 13, 14, and 19) were found to be the most protective against Aβ-induced neuronal cell death in PC12 cells. Compounds 4 and 14, containing N-methyl-4-piperidone linker, showed high acetylcholinesterase inhibitory activity as compared to reference drug donepezil. Molecular docking and QSAR (Quantitative Structure-Activity Relationship) studies were also carried out to determine the structural features that are responsible for the acetylcholinesterase and butyrylcholinesterase inhibitory activity.
Review: probiotics and their beneficial effects against various diseases

Iqbal MZ, Qadir MI, Hussain T, Janbaz KH, Khan YH, Ahmad B

Pak J Pharm Sci, 2014 Mar;27(2):405-15.
PMID: 24577933

Joint FAO/WHO expert's consultation report defines probiotics as: Live microorganisms which when administered in adequate amounts confer a health benefit on the host. Most commonly used probiotics are Lactic acid bacteria (LAB) and bifidobacteria. There are other examples of species used as probiotics (certain yeasts and bacilli). Probiotic supplements are popular now a days. From the beginning of 2000, research on probiotics has increased remarkably. Probiotics are now day's widely studied for their beneficial effects in treatment of many prevailing diseases. Here we reviewed the beneficiary effects of probiotics in some diseases.
Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia

Syaripuddin K, Kumar A, Sing KW, Halim MR, Nursyereen MN, Wilson JJ

Ecotoxicology, 2014 Sep;23(7):1164-71.
PMID: 24840106 DOI: 10.1007/s10646-014-1258-y

In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice.
Review: Ajwa date (Phoenix dactylifera)- an emerging plant in pharmacological research

Mallhi TH, Qadir MI, Ali M, Ahmad B, Khan YH, Rehman A

Pak J Pharm Sci, 2014 May;27(3):607-16.
PMID: 24811825

Date Fruits are consumed in Arab areas for a long time as a part of essential diet. Phoenix dactylifera belongs to family Arecaceae and its leaves, barks, pits, fruits and pollens have anticancer, antioxidant, hepatoprotective, antidiabetic, antihypertensive, antiulcertavie, anti-inflammatory, antiproliferative, antimutagenic, antidiarheal, antibacterial, antifungal and antiviral potential. Besides these, Dates also increase level of estrogen, testosterone, RBCs, Hb, PCV, reticulocytes and platelet counts. It can also cure lead induced heamotoxicity, side effects of methylprednisolon, male and female infertility. It has also cerebroprotective, neuroprotective and haemopoietic activity. Phoenix dactylifera can be used for number of complications if further evaluated and isolated. The present paper is an overview of pharmacological properties of Phoenix dactylifera reported in literature.
Fulltext Tuberculosis deaths: are we measuring accurately?

Atif M, Sulaiman SA, Shafie AA, Qamar Uz Zaman M, Asif M

J Pharm Policy Pract, 2014;7(1):16.
PMID: 25838918 DOI: 10.1186/2052-3211-7-16

Death among tuberculosis patients is one of the major reasons for non-attainment of 85% treatment success target set by World Health Organization. In this short paper, we evaluated whether the overall mortality rate in pulmonary tuberculosis is being affected by other comorbid conditions. All new smear positive pulmonary tuberculosis patients (N =336), who started their treatment at the chest clinic of the Penang General Hospital, between March 2010 and February 2011, were followed-up until December 2011. Tuberculosis treatment outcomes were reported according to six treatment outcome categories recommended by World Health Organization. The outcome category 'died' was defined as 'a patient who died due to tuberculosis or other cause during tuberculosis treatment'. Our findings showed that out of 336 smear positive pulmonary tuberculosis patients, 59 (17.6%) died during treatment (mortality rate = 1.003 cases per 1000 person-days of follow-up). Among the deceased patients, the mean age was 55.8 years (SD =16.17) and 49 were male. According to the mortality review forms, 29 deaths were tuberculosis-related, while the remaining 30 patients died due to reasons other than tuberculosis. Cerebrovascular accident (n =7), septicaemia shock (n =4) and acute coronary syndrome (n =4) were the most common non-tuberculosis related reasons for mortality in the patients. If the 30 patients, for whom tuberculosis was incidental to death, are excluded from the final cohort, the proportion of patients in the 'died' outcome category could be reduced to 9.5%. The treatment outcome criterion (i.e., died) set by World Health Organization has limitations. Therefore, it requires improvement for more objective evaluation of the performance of the National Tuberculosis Program.
Study site: Chest clinic, Hospital Pulau Pinang, Malaysia
Fulltext Breast cancer therapy by laser-induced Coulomb explosion of gold nanoparticles

Ashiq MG, Saeed MA, Tahir BA, Ibrahim N, Nadeem M

Chin. J. Cancer Res., 2013 Dec;25(6):756-61.
PMID: 24385705 DOI: 10.3978/j.issn.1000-9604.2013.12.08

Laser-induced Coulomb explosion of gold nanoparticles for breast cancer has been studied by nanophotolysis technique. This study aimed to investigate whether laser-induced bubble formation due to Coulomb explosion can provide an effective approach for selective damage of breast cancer with gold nanoparticles.
Watermelon lycopene and allied health claims

Naz A, Butt MS, Sultan MT, Qayyum MM, Niaz RS

EXCLI J, 2014;13:650-60.
PMID: 26417290

Presently, functional foods and nutraceuticals are gaining immense importance in the prevention of various maladies through dietary regimen module. Consumption of fruits and vegetables based diet has pursuit a range of bioactive components, especially phytochemicals targeting life threatening ailments. In this context, lycopene is an extensively studied antioxidant potentially present in watermelon, tomato, pink guava etc. Watermelon is one of the unique sources having readily available cis-isomeric lycopene. The distinctive aroma of watermelon is imparted by medium- and short-chain fatty acids along with geranial, ß-ionone and neral. Its consumption has been escalated owing to rich nutritional profile and allied health benefits. It is effective in reducing the extent of cancer insurgence, cardiovascular disorders, diabetes and macular diseases. The structural characteristics, physiochemical properties and therapeutic effects of lycopene are the limelight of the manuscript. However, further research investigations are still needed to address the health enhancing potential of watermelon lycopene.
Green biocides, a promising technology: current and future applications to industry and industrial processes

Ashraf MA, Ullah S, Ahmad I, Qureshi AK, Balkhair KS, Abdur Rehman M

J Sci Food Agric, 2014 Feb;94(3):388-403.
PMID: 23983055 DOI: 10.1002/jsfa.6371

The study of biofilms has skyrocketed in recent years due to increased awareness of the pervasiveness and impact of biofilms. It costs the USA literally billions of dollars every year in energy losses, equipment damage, product contamination and medical infections. But biofilms also offer huge potential for cleaning up hazardous waste sites, filtering municipal and industrial water and wastewater, and forming biobarriers to protect soil and groundwater from contamination. The complexity of biofilm activity and behavior requires research contributions from many disciplines such as biochemistry, engineering, mathematics and microbiology. The aim of this review is to provide a comprehensive analysis of emerging novel antimicrobial techniques, including those using myriad organic and inorganic products as well as genetic engineering techniques, the use of coordination complex molecules, composite materials and antimicrobial peptides and the use of lasers as such or their modified use in combination treatments. This review also addresses advanced and recent modifications, including methodological changes, and biocide efficacy enhancing strategies. This review will provide future planners of biofilm control technologies with a broad understanding and perspective on the use of biocides in the field of green developments for a sustainable future.
An RP-HPLC-UV method with SPE for cefotaxime in all-in-one total parenteral nutritional admixtures: application to stability studies

Iqbal MS, Bahari MB, Darwis Y, Iqbal MZ, Hayat A, Venkatesh G

J AOAC Int, 2013 6 19;96(2):290-4.
PMID: 23767352

A simple and selective RP-HPLC-UV method with SPE was developed and validated for the quantification of cefotaxime in all-in-one total parenteral nutrition (AIO-TPN) admixtures. Chromatographic separation was achieved on a 5 pm particle size C18 DB column (250 x 4.6 mm id) using the mobile phase ammonium acetate (25 mM, pH 4.0)-50% acetonitrile in methanol (80 + 20, v/v). The flow rate was 0.9 mL/min and the detection wavelength was 254 nm. The analyte was extracted from AIO-TPN admixtures by means of an SPE method. The cefotaxime calibration curve was linear over a concentration range of 100-1400 microg/mL with a correlation coefficient of > or = 0.9994. The intraday accuracy and precision for cefotaxime were < or = -3.15 and < or = 3.08%, respectively, whereas the interday accuracy and precision were < or = -2.48 and < or = 2.25%, respectively. The method was successfully applied to stability studies of cefotaxime in the presence of micronutrients together with low and high concentrations of macronutrients in AIO-TPN admixtures. Cefotaxime was degraded by 13.00 and 26.05% at room temperature (25 +/- 2 degrees C) after 72 h in low and high macronutrient concentration formulations of AIO-TPN admixtures, respectively. The values of cefotaxime degradation rates for low and high macronutrient concentration formulations of AIO-TPN admixtures were -0.164 and -0.353, respectively. These results indicated that there was a higher rate of degradation in the AIO-TPN admixture formulations containing high concentrations of macronutrients.
Bleomycin, etoposide and cisplatinum (BEP) chemotherapy for metastatic germ cell tumours: treatment outcomes at UKM medical centre, Malaysia

Azrif M, Leong YK, Aslan NM, Fong KV, Ismail F

Asian Pac J Cancer Prev, 2012;13(6):2467-71.
PMID: 22938405

INTRODUCTION: Although bleomycin/etoposide/cisplatinum (BEP) chemotherapy is established as the standard treatment for germ cell tumours, it requires significant experience in administration and toxicity management to maintain optimal dose intensity. A retrospective review of 30 patients was conducted at UKMMC to study treatment outcomes.
METHODS AND MATERIALS: Patients with GCTs and treated with at least two cycles of BEP chemotherapy between January 2003 and Oct 2009 were eligible for this study. Patients received 4-6 cycles of bleomycin 30,000IU IV D1, D8 and D15 and either etoposide 100mg/m2 IV D1- D5 and cisplatin 20mg/m2 IV D1- D5 (5 day BEP regimen) or etoposide 165 mg/m2 D1- D3 and cisplatin 50mg/m2 D1-3 (3 day BEP regimen) every three weeks per cycle. All patients received prophylactic granulocyte colony-stimulating factor (GCSF) from days 6 to 10 of each cycle. The overall response rates, 2 year progression-free survival and overall survival of the whole cohort were assessed.
RESULTS: Thirty patients fulfilled the inclusion criteria. Non-seminomatous GCTs comprised 93.3% of cases and gonadal and mediastinal primary sites were the most common. Sixty percent were classified as IGCCCG poor risk disease. Median follow-up was 26.6 months. The overall response rate (CR+PR) was 70%. The two year PFS and OS were 70% and 66%. There was a significant difference in terms of the overall response rate (85% vs 40%, p = 0.03) and in PFS (94.7% vs 50%, p = 0.003) between gonadal and extragonadal primary sites.
CONCLUSION: It is possible to achieve outcomes similar to those in international clinical trials with close monitoring and good supportive care of patients undergoing BEP chemotherapy. There is a strong argument for patients with IGCCCG poor prognosis disease to be treated in specialist tertiary centres to optimize treatment outcomes.
Takotsubo cardiomyopathy in association with hyperthyroidism

Zuhdi AS, Yaakob ZH, Sadiq MA, Ismail MD, Undok AW, Ahmad WA

Medicina (Kaunas), 2011;47(4):219-21.
PMID: 21829054

Takotsubo cardiomyopathy is a rare, acute, nonischemic cardiomyopathy causing transient left ventricular dysfunction, which can mimic myocardial infarction on its presentation. While many cardiac manifestations have been associated with hyperthyroidism, we report a rare case where it has precipitated takotsubo cardiomyopathy.
Fulltext Optical-based sensors for monitoring corrosion of reinforcement rebar via an etched cladding Bragg grating

Abu Hassan MR, Abu Bakar MH, Dambul K, Adikan FR

Sensors (Basel), 2012;12(11):15820-6.
PMID: 23202233 DOI: 10.3390/s121115820

In this paper, we present the development and testing of an optical-based sensor for monitoring the corrosion of reinforcement rebar. The testing was carried out using an 80% etched-cladding Fibre Bragg grating sensor to monitor the production of corrosion waste in a localized region of the rebar. Progression of corrosion can be sensed by observing the reflected wavelength shift of the FBG sensor. With the presence of corrosion, the etched-FBG reflected spectrum was shifted by 1.0 nm. In addition, with an increase in fringe pattern and continuously, step-like drop in power of the Bragg reflected spectrum was also displayed.
Synthesis, In vitro and Docking Studies of New Flavone Ethers as α-Glucosidase Inhibitors

Imran S, Taha M, Ismail NH, Kashif SM, Rahim F, Jamil W, et al.

Chem Biol Drug Des, 2016 Mar;87(3):361-73.
PMID: 26362113 DOI: 10.1111/cbdd.12666

We report herein the synthesis, α-glucosidase inhibition and docking studies for a series of 3-15 new flavones. A simple nucleophilic substitution reaction takes place between 3'hydroxyflavone (2) with halides to afford the new flavones. Chalcone (1), 3'hydroxyflavone (2) and the newly synthesized flavones (3-15) were being evaluated for their ability to inhibit activity of α-glucosidase. Compounds 2, 3, 5, 7-10 and 13 showed good inhibitory activity with IC50 values ranging between 1.26 and 36.44 μm as compared to acarbose (IC50 = 38.25 ± 0.12 μm). Compounds 5 (5.45 ± 0.08 μm), 7 (1.26 ± 0.01 μm) and 8 (8.66 ± 0.08 μm) showed excellent inhibitory activity, and this may be due to trifluoromethyl substitution that is common for these compounds. Compound 7, a 2,5-trifluoromethyl-substituted compound, recorded the highest inhibition activity, and it is thirty times better than the standard drug. Docking studies for compound 7 suggest that both trifluoromethyl substituents are well positioned in a binding pocket surrounded by Phe300, Phe177, Phe157, Ala278, Asp68, Tyr71 and Asp214. The ability of compound 7 to interact with Tyr71 and Phe177 is extremely significant as they are found to be important for substrates recognition by α-glucosidase.
Kinetic investigation and lifetime prediction of Cs-NIPAM-MBA-based thermo-responsive hydrogels

Othman MB, Khan A, Ahmad Z, Zakaria MR, Ullah F, Akil HM

Carbohydr Polym, 2016 Jan 20;136:1182-93.
PMID: 26572461 DOI: 10.1016/j.carbpol.2015.10.034

This study attempted to clarify the influence of a cross-linker, N,N-methylenebisacrylamide (MBA), and N-isopropylacrylamide (NIPAM) on the non-isothermal kinetic degradation, solid state and lifetime of hydrogels using the Flynn-Wall-Ozawa (F-W-O), Kissinger, and Coats-Redfern (C-Red) methods. The series of dual-responsive Cs-PNIPAM-MBA microgels were synthesized by soapless-emulsion free radical copolymerization in an aqueous medium at 70 °C. The thermal properties were investigated using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) under nitrogen atmosphere. The apparent activation energy using the chosen Flynn-Wall-Ozawa and Kissinger methods showed that they fitted each other. Meanwhile, the type of solid state mechanism was determined using the Coats-Redfern method proposed for F1 (pure Cs) and F2 (Cs-PNIPAM-MBA hydrogel series) types, which comprise random nucleation with one nucleus reacting on individual particles, and random nucleation with two nuclei reacting on individual particles, respectively. On average, a higher Ea was attributed to the greater cross-linking density of the Cs hydrogel.

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