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Decoding of the relationship between human brain activity and walking paths

Kamal SM, Sim S, Tee R, Nathan V, Aghasian E, Namazi H

Technol Health Care, 2020;28(4):381-390.
PMID: 31796717 DOI: 10.3233/THC-191965

BACKGROUND: The human brain controls all actions of the body. Walking is one of the most important actions that deals with the movement of the body. In fact, the brain controls and regulates human walking based on different conditions. One of the conditions that affects human walking is the complexity of path of movement. Therefore, the brain activity should change when a person walks on a path with different complexities.
OBJECTIVE: In this research we benefit from fractal analysis to study the effect of complexity of path of movement on the complexity of human brain reaction.
METHODS: For this purpose we calculate the fractal dimension of the electroencephalography (EEG) signal when subjects walk on different paths with different fractal dimensions (complexity).
RESULTS: The results of the analysis show that the complexity of brain activity increases with the increment of complexity of path of movement.
CONCLUSION: The method of analysis employed in this research can also be employed to analyse the reaction of the human heart and respiration when subjects move on paths with different complexities.
The assimilation of different carbon sources in Candida albicans: Fitness and pathogenicity

Lok B, Adam MAA, Kamal LZM, Chukwudi NA, Sandai R, Sandai D

Med Mycol, 2021 Feb 04;59(2):115-125.
PMID: 32944760 DOI: 10.1093/mmy/myaa080

Candida albicans is a commensal yeast commonly found on the skin and in the body. However, in immunocompromised individuals, the fungi could cause local and systemic infections. The carbon source available plays an important role in the establishment of C. albicans infections. The fungi's ability to assimilate a variety of carbon sources plays a vital role in its colonization, and by extension, its fitness and pathogenicity, as it often inhabits niches that are glucose-limited but rich in alternative carbon sources. A difference in carbon sources affect the growth and mating of C. albicans, which contributes to its pathogenicity as proliferation helps the fungi colonize its environment. The carbon source also affects its metabolism and signaling pathways, which are integral parts of the fungi's fitness and pathogenicity. As a big percentage of the carbon assimilated by C. albicans goes to cell wall biogenesis, the availability of different carbon sources will result in cell walls with variations in rigidity, adhesion, and surface hydrophobicity. In addition to the biofilm formation of the fungi, the carbon source also influences whether the fungi grow in yeast- or mycelial-form. Both forms play different roles in C. albicans's infection process. A better understanding of the role of the carbon sources in C. albicans's pathogenicity would contribute to more effective treatment solutions for fungal infections.
Molecular detection of tick-borne haemopathogens in shelter dogs and Rhipicephalus sanguineus (sensu lato) ticks from Peninsular Malaysia

Sipin Q, Mustaffa Kamal F, Watanabe M, Megat Abdul Rani PA, Low VL, Abdul Aziz NA

Comp Immunol Microbiol Infect Dis, 2020 Dec;73:101563.
PMID: 33120297 DOI: 10.1016/j.cimid.2020.101563

Ticks are important vectors in transmitting various pathogens and they could jeopardize the health and welfare of humans and animals worldwide. The present study aimed to investigate the presence of important tick-borne haemopathogens (TBH) in dogs and ticks via polymerase chain reaction (PCR) assays. A total of 220 blood samples and 140 ticks were collected from 10 animal shelters in Peninsular Malaysia. Of 220 blood samples, 77 (35 %) were positive to TBH, of which 20 % were E. canis, 12 % were A. platys, 7 % were B. gibsoni and 7 % were B. vogeli. All ticks were identified as Rhipicephalus sanguineus with five samples (3.57 %) positive with TBH. Co-infections of TBH (0.45-9.55 %) in dogs were also observed in this study.
Simulated gastrointestinal digestion of camel and bovine casein hydrolysates: Identification and characterization of novel anti-diabetic bioactive peptides

Mudgil P, Kamal H, Priya Kilari B, Mohd Salim MAS, Gan CY, Maqsood S

Food Chem, 2021 Aug 15;353:129374.
PMID: 33740505 DOI: 10.1016/j.foodchem.2021.129374

Camel milk proteins are an important substrate for bioactive peptides generation. This study investigates in-vitro antidiabetic effect (via inhibition of α-amylase (AA), α-glucosidase (AG) and dipeptidyl peptidase IV (DPP-IV)) of bovine (BC) and camel casein (CC) hydrolysates. Further, effect of simulated gastrointestinal digestion (SGID) on inhibitory potential of generated hydrolysates was also explored. Both BC and CC hydrolysates displayed potent inhibitory properties against AA (IC50 value- 0.58 & 0.59 mg/mL), AG (IC50 value- 1.04 & 0.59 mg/mL) and DPP-IV (IC50 value- 0.62 & 0.66 mg/mL), respectively. Among different peptides identified in BC and CC hydrolysates, it was observed that FLWPEYGAL was predicted to be most potent inhibitory peptide against AA. While LPTGWLM, MFE and GPAHCLL as most active inhibitor of AG and HLPGRG, QNVLPLH and PLMLP were predicted to be active against DPP-IV. Overall, BC and CC hydrolysates can be proposed to be used in different food formulations as functional antidiabetic agents.
Palm Fatty Acid Functionalized Fe₃O₄ Nanoparticles as Highly Selective Oil Adsorption Material

Rozi SKM, Shahabuddin S, Manan NSA, Mohamad S, Kamal SAA, Rahman SA

J Nanosci Nanotechnol, 2018 May 01;18(5):3248-3256.
PMID: 29442825 DOI: 10.1166/jnn.2018.14699

The present work highlights the facile synthesis of hydrophobic palm fatty acid functionalized Fe3O4 nanoparticles (MNP-FA) for the efficient removal of oils from the surface of water. An intense hydrophobic layer was introduced on the surface of Fe3O4 nanoparticles functionalized by the palm fatty acid obtained from the hydrolysis of palm olein. Scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), Energy dispersive X-ray spectroscopy (EDX) and water contact angle analysis (WCA) measurements were used to characterize the newly fabricated palm fatty acid adorned magnetic Fe3O4 nanoparticles (MNP-FA). The obtained results confirmed the successful synthesis of palm fatty acid-functionalized magnetic nanoparticles. Oil removal tests performed with MNP-FA revealed that this newly prepared material could selectively adsorb lubricating oil up to 3.5 times of the particles' weight while completely repelling water. The main parameters affecting the adsorption of oil i.e., sorption time, mass of sorbent and pH of water were optimized.
Fulltext Mechanistic Actions between Garcinia atroviridis Essential Oil and 2 Deoxy-d-glucose in Cultured PANC-1 Human Pancreatic Cancer Cells

Nik Mohamed Kamal NNS, Abdul Aziz FA, Tan WN, Fauzi AN, Lim V

Molecules, 2021 Jun 09;26(12).
PMID: 34207699 DOI: 10.3390/molecules26123518

Pancreatic cancer is an aggressive disease that progresses in a relatively symptom-free manner; thus, is difficult to detect and treat. Essential oil is reported to exhibit pharmacological properties, besides its common and well-known function as aromatherapy. Therefore, this study herein aimed to investigate the anti-proliferative effect of essential oil extracted from leaves of Garcinia atroviridis (EO-L) against PANC-1 human pancreatic cancer cell line. The cell growth inhibitory concentration at 50% (IC50) and selective index (SI) values of EO-L analyses were determined as 78 µg/mL and 1.23, respectively. Combination index (CI) analysis revealed moderate synergism (CI values of 0.36 to 0.75) between EO-L and 2 deoxy-d-glucose (2-DG) treatments. The treatments of PANC-1 cells with EO-L, 2-DG and EOL+2DG showed evidence of depolarization of mitochondrial membrane potential, cell growth arrest and apoptosis. The molecular mechanism causing the anti-proliferative effect between EO-L and 2-DG is potentially through pronounced up-regulation of P53 (4.40-fold), HIF1α (1.92-fold), HK2 (2.88-fold) and down-regulation of CYP3A5 (0.11-fold), as supported by quantitative mRNA expression analysis. Collectively, the current data suggest that the combination of two anti-proliferative agents, EO-L and 2-DG, can potentially be explored as therapeutic treatments and as potentiating agents to conventional therapy against human pancreatic cancer.
Fulltext Longitudinal Vitamin D Deficiency Among Malaysian Pregnant Women and Its Correlation With Neonatal Serum 25-Hydroxyvitamin D Levels

Mustapa Kamal Basha MA, Abdul Majid H, Razali N, Abd Rashed A, Muhammad H, Yahya A

Front Public Health, 2021;9:654292.
PMID: 34268285 DOI: 10.3389/fpubh.2021.654292

Objective: This study aimed to investigate the longitudinal relationship between maternal vitamin D concentrations during pregnancy and neonatal vitamin D concentrations at birth. Materials and Methods: A prospective cohort of 236 healthy pregnant women from various ethnicity in early pregnancy (≤20 weeks of pregnancy) was followed at late pregnancy (28-40 weeks of pregnancy) and birth. Maternal serum 25-hydroxyvitamin D (25(OH)D) was assessed at early pregnancy (baseline) and late pregnancy, while neonatal cord serum 25(OH)D at birth. General estimating equations (GEE) were used to analyze the longitudinal association of maternal serum 25(OH)D levels during pregnancy and neonatal cord serum 25(OH)D levels at birth with adjusting for the time exposure, maternal weight gain, ethnicity, and skin type. Results: The results showed that the prevalence of vitamin D deficiency (25(OH)D <50 nmol/L) was at 89.9, 92.2, and 96.1% in early, late pregnancy and in neonatal cord serum, respectively. The GEE analysis showed a trend that longitudinal vitamin D deficiency during pregnancy leads to lower vitamin D concentrations in neonatal cord blood (RR = 1.17; 95% CI (1.05-1.36); p = 0.04). Conclusion: Longitudinal vitamin D deficiency during pregnancy leads to vitamin D deficiency in neonates at birth. A further trial is needed to affirm this association.
Fulltext Hydrolysis and characterization of sugar recovery from bakery waste under optimized subcritical water conditions

Mohd Thani N, Mustapa Kamal SM, Taip FS, Sulaiman A, Omar R, Siajam SI

J Food Sci Technol, 2020 Aug;57(8):3108-3118.
PMID: 32612303 DOI: 10.1007/s13197-020-04345-1

Subcritical water hydrolysis process for sugar recovery from leftover croissants (LC) and leftover doughnuts (LD) was optimised using response surface methodology with three process parameters as dependent variables and sugar yield as the response. The process parameters: temperature (160-200 °C), time (5-15 min), and solid loading (10-50%), on the sugar yield were investigated. For the LC sample, the optimised process conditions were determined to be: 200 °C, 6.17 min, and 10% solid loading producing an 80% hydrolysis yield of 466.11 ± 0.67 mg/g. Comparatively, the LD sample optimisation parameters were: 200 °C, 5 min, and 10% solid loading producing a 76.18% hydrolysis yield of 394.34 ± 0.33 mg/g. The sugar extracts were further characterise; which through scanning electron microscopy revealed the LC had most starch granules rupture during hydrolysis, while Fourier-transform infrared spectroscopy detected the presence of monosaccharides and oligosaccharides for both LC and LD. 5-hydroxymethylfurfural (5-HMF), a sugar degradation by-product, was also detected with 39.16 ± 0.61 and 20.59 ± 0.81 mg/g for the LC and LD, respectively, at optimal conditions.
Current practices of Malaysian speech-language pathologists working with dysarthria

Altaher AM, Chu SY, Park HR, Khoong ESQ, Mustaffa Kamal R, Mcconnell G

Int J Speech Lang Pathol, 2021 Aug 04.
PMID: 34348530 DOI: 10.1080/17549507.2021.1958921

Purpose: This study investigated the practice patterns used by Malaysian speech-language pathologists (SLPs) with patients with dysarthria, identified challenges perceived by SLPs and explored strategies to address perceived barriers for improving dysarthria management.Method: Two studies were conducted. Study 1 disseminated a 30-item survey questionnaire electronically via google link to SLPs in the Malaysian Speech-Language-Hearing Association through e-mail lists. Responses were analysed using descriptive statistics. In Study 2, semi-structured interviews of twelve SLPs who managed patients with dysarthria were conducted. Data were transcribed verbatim and analysed using the thematic analysis method.Result: Three major themes and ten sub-themes emerged from the interviews, including "assessment and treatment practices", "challenges", and "overcoming challenges". SLPs' practice of assessment and treatment of dysarthria were predominantly impairment-based. Respondents (64%) who never used standardised assessment tools valued textbooks more as sources of evidence and had a lower level of confidence in their knowledge about dysarthria compared to those who used standardised tools.Conclusion: Focus now needs to be on the education needs of our SLPs, on both the university training and continuing education levels, for direction of the development of professional training courses. Ongoing research and public awareness are required to guide clinical management decisions.
Fulltext Biomass and Habitat Characteristics of Epiphytic Macroalgae in the Sibuti Mangroves, Sarawak, Malaysia

Isa HM, Kamal AH, Idris MH, Rosli Z, Ismail J

Trop Life Sci Res, 2017 Jan;28(1):1-21.
PMID: 28228913 MyJurnal DOI: 10.21315/tlsr2017.28.1.1

Mangroves support diverse macroalgal assemblages as epibionts on their roots and tree trunks. These algae provide nutrients to the primary consumers in the aquatic food web and have been reported to be substantial contributors to marine ecosystems. The species diversity, biomass, and habitat characteristics of mangrove macroalgae were investigated at three stations in the Sibuti mangrove estuary, Sarawak, Malaysia, from November 2012 to October 2013. Three groups of macroalgae were recorded and were found to be growing on mangrove prop roots, namely Rhodophyta (Caloglossa ogasawaraensis, Caloglossa adhaerens, Caloglossa stipitata, Bostrychia anomala, and Hypnea sp.), Chlorophyta (Chaetomorpha minima and Chaetomorpha sp.), and Phaeophyta (Dictyota sp.). The biomass of macroalgae was not influenced (p>0.05) by the season in this mangrove forest habitat. The macroalgal species Hypnea sp. contributed the highest biomass at both Station 1 (210.56 mg/cm(2)) and Station 2 (141.72 mg/cm(2)), while the highest biomass was contributed by B. anomala (185.89 mg/cm(2)) at Station 3. This study shows that the species distribution and assemblages of mangrove macroalgae were influenced by environmental parameters such as water nutrients, dissolved solids, and salinity in the estuarine mangrove habitats of Sibuti, Sarawak.
Femtomolar detection of dopamine using surface plasmon resonance sensor based on chitosan/graphene quantum dots thin film

Kamal Eddin FB, Fen YW, Omar NAS, Liew JYC, Daniyal WMEMM

Spectrochim Acta A Mol Biomol Spectrosc, 2021 Dec 15;263:120202.
PMID: 34333400 DOI: 10.1016/j.saa.2021.120202

Due to the crucial role of dopamine (DA) in health and peripheral nervous systems, it is particularly important to develop an efficient and accurate sensor to monitor and determine DA concentrations for diagnostic purposes and diseases prevention. Up to now, using surface plasmon resonance (SPR) sensors in DA determination is very limited and its application still at the primary stage. In this work, a simple and ultra-sensitive SPR sensor was constructed for DA detection by preparation of chitosan- graphene quantum dots (CS-GQDs) thin film as the sensing layer. Other SPR measurements were conducted using different sensing layers; GQDs, CS for comparison. The proposed thin films were prepared by spin coating technique. The developed CS-GQDs thin film-based SPR sensor was successfully tested in DA concentration range from 0 fM to 1 pM. The designed SPR sensor showed outstanding performance in detecting DA sensitively (S = 0.011°/fM, R2 = 0.8174) with low detection limit of 1.0 fM has been achieved for the first time. The increased angular shift of SPR dip, narrow full width half maximum of the SPR curves, excellent signal-to-noise ratio and figure of merit, and a binding affinity constant (KA) of 2.962 PM-1 demonstrated the potential of this sensor to detect DA with high accuracy. Overall, it was concluded that the proposed sensor would serve as a valuable tool in clinical diagnostic for the serious neurological disorders. This in turns has a significant socio-economic impact.
Fulltext Design and experimental analysis of dual-band polarization converting metasurface for microwave applications

Khan B, Kamal B, Ullah S, Khan I, Shah JA, Chen J

Sci Rep, 2020 Sep 21;10(1):15393.
PMID: 32958835 DOI: 10.1038/s41598-020-71959-y

The manipulation of polarization state of electromagnetic waves is of great importance in many practical applications. In this paper, the reflection characteristics of a thin and dual-band metasurface are examined in the microwave frequency regime. The metasurface consists of a 22 × 22 element array of periodic unit cells. The geometry of the unit cell consists of three layers, including a 45° inclined dipole shape metal patch on top, which is backed by a 1.6 mm thick FR-4 substrate in the middle, and a fully reflective metallic mirror at the bottom. The proposed surface is exposed to horizontally (x) or vertically (y) polarized plane waves and the co and cross polarization reflection coefficients of the reflected waves are investigated experimentally in the 6-26 GHz frequency range. The metasurface is designed to convert incident waves of known polarization state (horizontal or vertical) to orthogonal polarization state (vertical and horizontal) in two distinct frequency bands, i.e. 7.1-8 GHz and 13.3-25.8 GHz. In these two frequency bands the simulated and experimental results are in good agreement. The polarization conversion ratio (PCR) of the surface is greater than 95% in the targeted frequency bands. A detailed parametric analysis of the metasurface is also discussed in this work and it has been estimated that the surface has the additional ability to convert linearly polarized waves to circularly polarized waves at several distinct frequencies. The proposed metasurface can be utilized in sensor applications, stealth technology, electromagnetic measurements, and antennas design.
Fulltext Effect of Supporting Background Electrolytes on the Nanostructure Morphologies and Electrochemical Behaviors of Electrodeposited Gold Nanoparticles on Glassy Carbon Electrode Surfaces

Zakaria ND, Omar MH, Ahmad Kamal NN, Abdul Razak K, Sönmez T, Balakrishnan V, et al.

ACS Omega, 2021 Sep 28;6(38):24419-24431.
PMID: 34604624 DOI: 10.1021/acsomega.1c02670

Electrodeposition is an electrochemical method employed to deposit stable and robust gold nanoparticles (AuNPs) on electrode surfaces for creating chemically modified electrodes (CMEs). The use of several electrodeposition techniques with different experimental parameters allow in obtaining various surface morphologies of AuNPs deposited on the electrode surface. By considering the electrodeposition of AuNPs in various background electrolytes could play an important strategy in finding the most suitable formation of the electrodeposited AuNP films on the electrode surface. This is because different electrode roughnesses can have different effects on the electrochemical activities of the modified electrodes. Thus, in this study, the electrodeposition of AuNPs onto the glassy carbon (GC) electrode surfaces in various aqueous neutral and acidic electrolytes was achieved by using the cyclic voltammetry (CV) technique with no adjustable CV parameters. Then, surface morphologies and electrochemical activities of the electrodeposited AuNPs were investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), CV, and electrochemical impedance spectroscopy (EIS). The obtained SEM and 3D-AFM images show that AuNPs deposited at the GC electrode prepared in NaNO3 solution form a significantly better, uniform, and homogeneous electrodeposited AuNP film on the GC electrode surface with nanoparticle sizes ranging from ∼36 to 60 nm. Meanwhile, from the electrochemical performances of the AuNP-modified GC electrodes, characterized by using a mixture of ferricyanide and ferrocyanide ions [Fe(CN6)3-/4-], there is no significant difference observed in the case of charge-transfer resistances (R ct) and heterogeneous electron-transfer rate constants (k o), although there are differences in the surface morphologies of the electrodeposited AuNP films. Remarkably, the R ct values of the AuNP-modified GC electrodes are lower than those of the bare GC electrode by 18-fold, as the R ct values were found to be ∼6 Ω (p < 0.001, n = 3). This has resulted in obtaining k o values of AuNP-modified GC electrodes between the magnitude of 10-2 and 10-3 cm s-1, giving a faster electron-transfer rate than that of the bare GC electrode (10-4 cm s-1). This study confirms that using an appropriate supporting background electrolyte plays a critical role in preparing electrodeposited AuNP films. This approach could lead to nanostructures with a more densely, uniformly, and homogeneously electrodeposited AuNP film on the electrode surfaces, albeit utilizing an easy and simple preparation method.
Natural Products Combating Neurodegeneration: Parkinson's Disease

Solayman M, Islam MA, Alam F, Khalil MI, Kamal MA, Gan SH

Curr Drug Metab, 2017;18(1):50-61.
PMID: 27396919 DOI: 10.2174/1389200217666160709204826

Parkinson's disease (PD) is characterized by neurodegeneration and a progressive functional impairment of the midbrain nigral dopaminergic neurons. The cause remains unknown; however, several pathological processes and central factors, such as protein aggregation, mitochondrial dysfunction, iron accumulation, neuroinflammation and oxidative stress, have been reported. The current treatment method primarily targets symptoms by using anti-Parkinson drugs such as levodopa, carbidopa, dopamine (DA) agonists, monoamine oxidase type B inhibitors and anticholinergics to replace DA. When drug therapy is not satisfactory, surgical treatments are recommended. Unfortunately, the existing conventional strategies that target PD are associated with numerous side effects and possess an economic burden. Therefore, novel therapeutic approaches that regulate the pathways leading to neuronal death and dysfunction are necessary. For many years, nature has provided the primary resource for the discovery of potential therapeutic agents. Remarkably, many natural products from medicinal plants, fruits and vegetables have been demonstrated to be efficacious anti-Parkinson agents. These products possess neuroprotective properties as a result of not only their wellrecognized anti-oxidative and anti-inflammatory activities but also their inhibitory roles regarding iron accumulation, protein misfolding and the maintenance of proteasomal degradation, as well as mitochondrial homeostasis. The aim of this review is to report the available anti-Parkinson agents based on natural products and delineate their therapeutic actions, which act on various pathways. Overall, this review emphasizes the types of natural products that are potential future resources in the treatment of PD as novel regimens or supplementary agents.
Fulltext Expression profiles of immune mediators in feline Coronavirus-infected cells and clinical samples of feline Coronavirus-positive cats

Safi N, Haghani A, Ng SW, Selvarajah GT, Mustaffa-Kamal F, Omar AR

BMC Vet Res, 2017 Apr 07;13(1):92.
PMID: 28388950 DOI: 10.1186/s12917-017-1019-2

BACKGROUND: There are two biotypes of feline coronavirus (FCoV): the self-limiting feline enteric coronavirus (FECV) and the feline infectious peritonitis virus (FIPV), which causes feline infectious peritonitis (FIP), a fatal disease associated with cats living in multi-cat environments. This study provides an insight on the various immune mediators detected in FCoV-positive cats which may be responsible for the development of FIP.
RESULTS: In this study, using real-time PCR and multiplex bead-based immunoassay, the expression profiles of several immune mediators were examined in Crandell-Reese feline kidney (CRFK) cells infected with the feline coronavirus (FCoV) strain FIPV 79-1146 and in samples obtained from FCoV-positive cats. CRFK cells infected with FIPV 79-1146 showed an increase in the expression of interferon-related genes and pro-inflammatory cytokines such as MX1, viperin, CXCL10, CCL8, RANTES, KC, MCP1, and IL8. In addition, an increase in the expression of the above cytokines as well as GM-CSF and IFNγ was also detected in the PBMC, serum, and peritoneal effusions of FCoV-positive cats. Although the expression of MX1 and viperin genes was variable between cats, the expression of these two genes was relatively higher in cats having peritoneal effusion compared to cats without clinically obvious effusion. Higher viral load was also detected in the supernatant of peritoneal effusions compared to in the plasma of FCoV-positive cats. As expected, the secretion of IL1β, IL6 and TNFα was readily detected in the supernatant of peritoneal effusions of the FCoV-positive cats.
CONCLUSIONS: This study has identified various pro-inflammatory cytokines and interferon-related genes such as MX1, viperin, CXCL10, CCL8, RANTES, KC, MCP1, IL8, GM-CSF and IFNγ in FCoV-positive cats. With the exception of MX1 and viperin, no distinct pattern of immune mediators was observed that distinguished between FCoV-positive cats with and without peritoneal effusion. Further studies based on definitive diagnosis of FIP need to be performed to confirm the clinical importance of this study.
Novel combination of zero-valent Cu and Ag nanoparticles @ cellulose acetate nanocomposite for the reduction of 4-nitro phenol

Khan FU, Asimullah, Khan SB, Kamal T, Asiri AM, Khan IU, et al.

Int J Biol Macromol, 2017 Sep;102:868-877.
PMID: 28428128 DOI: 10.1016/j.ijbiomac.2017.04.062

A very simple and low-cost procedure has been adopted to synthesize efficient copper (Cu), silver (Ag) and copper-silver (Cu-Ag) mixed nanoparticles on the surface of pure cellulose acetate (CA) and cellulose acetate-copper oxide nanocomposite (CA-CuO). All nanoparticles loaded onto CA and CA-CuO presented excellent catalytic ability, but Cu-Ag nanoparticles loaded onto CA-CuO (Cu0-Ag0/CA-CuO) exhibited outstanding catalytic efficiency to convert 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) in the presence of NaBH4. Additionally, the Cu0-Ag0/CA-CuO can be easily recovered by removing the sheet from the reaction media, and can be recycled several times, maintaining high catalytic ability for four cycles.
Fulltext Isolation, Purification, and Characterization of Five Active Diketopiperazine Derivatives from Endophytic Streptomyces SUK 25 with Antimicrobial and Cytotoxic Activities

Alshaibani M, Zin NM, Jalil J, Sidik N, Ahmad SJ, Kamal N, et al.

J Microbiol Biotechnol, 2017 07 28;27(7):1249-1256.
PMID: 28535606 DOI: 10.4014/jmb.1608.08032

In our search for new sources of bioactive secondary metabolites from Streptomyces sp., the ethyl acetate extracts from endophytic Streptomyces SUK 25 afforded five active diketopiperazine (DKP) compounds. The aim of this study was to characterize the bioactive compounds isolated from endophytic Streptomyces SUK 25 and evaluate their bioactivity against multiple drug resistance (MDR) bacteria such as Enterococcus raffinosus, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., and their cytotoxic activities against the human hepatoma (HepaRG) cell line. The production of secondary metabolites by this strain was optimized through Thornton's medium. Isolation, purification, and identification of the bioactive compounds were carried out using high-performance liquid chromatography, high-resolution mass liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance, and cryopreserved HepaRG cells were selected to test the cytotoxicity. The results showed that endophytic Streptomyces SUK 25 produces four active DKP compounds and an acetamide derivative, which were elucidated as cyclo-(L-Val-L-Pro), cyclo-(L-Leu-L-Pro), cyclo-(L-Phe-L-Pro), cyclo-(L-Val-L-Phe), and N-(7-hydroxy-6-methyl-octyl)-acetamide. These active compounds exhibited activity against methicillin-resistant S. aureus ATCC 43300 and Enterococcus raffinosus, with low toxicity against human hepatoma HepaRG cells. Endophytic Streptomyces SUK 25 has the ability to produce DKP derivatives biologically active against some MDR bacteria with relatively low toxicity against HepaRG cells line.
Thrombotic management of antiphospholipid syndrome: towards novel targeted therapies

Islam MA, Alam F, Wong KK, Kamal MA, Gan SH

Curr Vasc Pharmacol, 2017;15(4):313-326.
PMID: 28056758 DOI: 10.2174/1570161115666170105120931

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombosis and/or pregnancy morbidity with persistent levels of antiphospholipid antibodies (aPLs). The development of thrombosis in APS is mediated by aPLs and contributes to the high mortality rate in APS patients. However, although APS has been reported for more than 30 years, there has been no optimal regimen for its prevention or for the management of thrombosis, mainly because the mainstay treatment strategies for managing APS are not targeted towards aPL-mediated thrombotic pathophysiology. Instead, the treatments commonly used are aimed at general thrombotic disorders. Warfarin is the most commonly used vitamin K antagonist (VKA), in addition to anti-platelet medications, such as aspirin and clopidogrel. Over the last decade, novel non-VKA oral anticoagulants, including rivaroxaban, apixaban and dabigatran, as well as immunomodulatory agents, such as rituximab, eculizumab, hydroxychloroquine, statins and sirolimus, have also been used. In this review, we discuss the current treatment strategies and future treatment outlook for thrombotic APS.
Alzheimer's Disease and Natural Products: Future Regimens Emerging from Nature

Islam MA, Khandker SS, Alam F, Khalil MI, Kamal MA, Gan SH

Curr Top Med Chem, 2017;17(12):1408-1428.
PMID: 28049401 DOI: 10.2174/1568026617666170103163054

Alzheimer's disease (AD), which largely affects the elderly, has become a global burden. Patients with AD have both short- and long-term memory impairments. The neuronal loss in AD occurs due to abnormally folded amyloid beta proteins and aggregation of hyperphosphorylated tau proteins in the brain. Eventually, amyloid plaques and neurofibrillary tangles are formed, which subsequently disintegrate the neuronal transport system. There are several factors which are involved in AD pathogenesis, including oxidative stress, inflammation and the presence of metal ions. The modern therapies utilized for AD treatment have many adverse effects, driving the quest for more safe and effective medications. Many dietary components, including different types of fruits, vegetables, spices, and marine products as well as a Mediterranean diet, are a good source of antioxidants and have anti-inflammatory properties, with many showing substantial potential against AD pathogenesis. In this review, we discuss the potential of these foods for treating AD and opportunities for developing disease-targeted drugs from active compounds extracted from natural dietary products.
Therapeutic Suppression of Nonsense Mutation: An Emerging Target in Multiple Diseases and Thrombotic Disorders

Asiful Islam M, Alam F, Kamal MA, Gan SH, Wong KK, Sasongko TH

Curr Pharm Des, 2017;23(11):1598-1609.
PMID: 27875971 DOI: 10.2174/1381612823666161122142950

Nonsense mutations contribute to approximately 10-30% of the total human inherited diseases via disruption of protein translation. If any of the three termination codons (UGA, UAG and UAA) emerges prematurely [known as premature termination codon (PTC)] before the natural canonical stop codon, truncated nonfunctional proteins or proteins with deleterious loss or gain-of-function activities are synthesized, followed by the development of nonsense mutation-mediated diseases. In the past decade, PTC-associated diseases captured much attention in biomedical research, especially as molecular therapeutic targets via nonsense suppression (i.e. translational readthrough) regimens. In this review, we highlighted different treatment strategies of PTC targeting readthrough therapeutics including the use of aminoglycosides, ataluren (formerly known as PTC124), suppressor tRNAs, nonsense-mediated mRNA decay, pseudouridylation and CRISPR/Cas9 system to treat PTC-mediated diseases. In addition, as thrombotic disorders are a group of disease with major burdens worldwide, 19 potential genes containing a total of 705 PTCs that cause 21 thrombotic disorders have been listed based on the data reanalysis from the 'GeneCards® - Human Gene Database' and 'Human Gene Mutation Database' (HGMD®). These PTC-containing genes can be potential targets amenable for different readthrough therapeutic strategies in the future.

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