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Oleic Acid Coated Silver Nanoparticles Showed Better in Vitro Amoebicidal Effects against Naegleria fowleri than Amphotericin B

Rajendran K, Anwar A, Khan NA, Aslam Z, Raza Shah M, Siddiqui R

ACS Chem Neurosci, 2020 08 19;11(16):2431-2437.
PMID: 31347828 DOI: 10.1021/acschemneuro.9b00289

Naegleria fowleri (N. fowleri) causes primary amoebic meningoencephalitis (PAM) which almost always results in death. N. fowleri is also known as "brain-eating amoeba" due to its literal infestation of the brain leading to an inflammatory response in the brain tissues. Currently, there is no single drug that is available to treat PAM, and most treatments are combinations of antifungal, anticancer, and anti-inflammatory drugs. Recently nanotechnology has gained attention in chemotherapeutic research converging on drug delivery, while oleic acid (OA) has shown positive effects on the human immune system and inflammatory processes. In continuation of our recent research in which we reported the effects of oleic acid conjugated with silver nanoparticles (OA-AgNPs) against free-living amoeba Acanthamoeba castellanii, in this report, we show their antiamoebic effects against N. fowleri. OA alone and its nanoconjugates were tested against the amoeba by using amoebicidal and host cell cytopathogenicity assays. Trypan blue exclusion assay was used to determine cell viability. The results revealed that OA-AgNPs exhibited significantly enhanced antiamoebic effects (P < 0.05) against N. fowleri as compared to OA alone. Evidently, lactate dehydrogenase release shows reduced N. fowleri-mediated host cell cytotoxicity. Based on our study, we anticipate that further studies on OA-AgNPs could potentially provide an alternative treatment of PAM.
Aluminium removal and recovery from wastewater and soil using isolated indigenous bacteria

Purwanti IF, Kurniawan SB, Ismail N', Imron MF, Abdullah SRS

J Environ Manage, 2019 Nov 01;249:109412.
PMID: 31445374 DOI: 10.1016/j.jenvman.2019.109412

This paper elucidates the capability of isolated indigenous bacteria to remove aluminium from wastewater and soil. Two indigenous species of Brochothrix thermosphacta and Vibrio alginolyticus were isolated from an aluminium-contaminated site. These two species were used to treat aluminium-containing wastewater and contaminated soil using the bioaugmentation method. B. thermosphacta showed the highest aluminium removal of 57.87 ± 0.45% while V. alginolyticus can remove aluminium up to 59.72 ± 0.33% from wastewater. For aluminium-contaminated soil, B. thermosphacta and V. alginolyticus, showed a highest removal of only 4.58 ± 0.44% and 5.48 ± 0.58%, respectively. The bioaugmentation method is more suitable to be used to treat aluminium in wastewater compared to contaminated soil. The produced biomass separation after wastewater treatment was so much easier and applicable, compared to the produced biomass handling from contaminated soil treatment. A 48.55 ± 2.45% and 40.12 ± 4.55% of aluminium can be recovered from B. thermosphacta and V. alginolyticus biomass, respectively, with 100 mg/L initial aluminium concentration in wastewater.
Dehydrogenation Properties and Catalytic Mechanism of the K2NiF6-Doped NaAlH4 System

Mustafa NS, Yahya MS, Sazelee N, Ali NA, Ismail M

ACS Omega, 2018 Dec 31;3(12):17100-17107.
PMID: 31458330 DOI: 10.1021/acsomega.8b02281

The K2NiF6 catalytic effect on the NaAlH4 dehydrogenation properties was studied in this work. The desorption temperature was studied using temperature-programmed desorption and exhibited a lower onset hydrogen release after doped with different wt % of K2NiF6 (5, 10, 15 and 20 wt %). It was found that the NaAlH4 doped with 5 wt % K2NiF6 showed the optimal value that can reduce the onset desorption temperature of about 160 °C compared to 190 °C for the milled NaAlH4. The NaAlH4 + 5 wt % K2NiF6 sample showed faster desorption kinetics where 1.5 wt % of hydrogen was released in 30 min at 150 °C. In contrast, the milled NaAlH4 only released about 0.2 wt % within the same time and temperature. From the Kissinger analysis, the apparent activation energy was 114.7 kJ/mol for the milled NaAlH4 and 89.9 kJ/mol for the NaAlH4-doped 5 wt % K2NiF6, indicating that the addition of K2NiF6 reduced the activation energy for hydrogen desorption of NaAlH4. It is deduced that the new phases of AlNi, NaF, and KH that were formed in situ during the dehydrogenation process are the key factors for the improvement of dehydrogenation properties of NaAlH4.
Recommendations for improving clinical trial design to facilitate the study of youth-onset type 2 diabetes

Jalaludin MY, Barrientos-Pérez M, Hafez M, Lynch J, Shehadeh N, Turan S, et al.

Clin Trials, 2020 02;17(1):87-98.
PMID: 31450961 DOI: 10.1177/1740774519870190

BACKGROUND: The prevalence of type 2 diabetes is increasing in youths and differs from adult-onset type 2 diabetes in its characteristics and progression. Currently, only two drugs are approved for youth-onset type 2 diabetes and many patients are not meeting glycemic targets. Clearly, there is an urgent need to complete clinical trials in youths with type 2 diabetes to increase the therapeutic choice for these patients. However, factors such as limited patient numbers, unwillingness of patients to participate in trials, failure to meet strict inclusion and exclusion criteria, and poor clinic attendance have limited the size and number of trials in this complicated patient demographic.
RECOMMENDATIONS: This is a narrative opinion piece on the design of clinical trials in youth-onset type 2 diabetes prepared by researchers who undertake this type of study in different countries. The review addresses possible ways to enhance trial designs in youth-onset type 2 diabetes to meet regulatory requirements, while minimizing the barriers to patients' participation. The definition of adolescence, recruitment of sufficient patient numbers, increasing flexibility in selection criteria, improving convenience of trial visits, requirements of a control group, possible endpoints, and trial compliance are all considered. The authors recommend allowing extrapolation from adult data, using multiple interventional arms within future trials, broadening inclusion criteria, and focusing on endpoints beyond glucose control, among others, in order to improve the successful completion of more trials in this population.
CONCLUSIONS: Improvements in trial design will enable better recruitment and retention and thereby more evidence for treatment outcomes for youth-onset type 2 diabetes.
Fulltext The relationship between bacterial sources and genotype to the antimicrobial resistance pattern of Burkholderia pseudomallei

Sadiq MA, Hassan L, Aziz SA, Zakaria Z, Musa HI, Amin MM

Vet World, 2018 Nov;11(10):1404-1408.
PMID: 30532493 DOI: 10.14202/vetworld.2018.1404-1408

Background: Melioidosis is a fatal emerging infectious disease of both man and animal caused by bacteria Burkholderia pseudomallei. Variations were suggested to have existed among the different B. pseudomallei clinical strains/genotypes which may implicate bacterial susceptibility and resistance toward antibiotics.
Aim: This study was designed to determine whether the phenotypic antibiotic resistance pattern of B. pseudomallei is associated with the source of isolates and the genotype.
Materials and Methods: A collection of 111 B. pseudomallei isolates from veterinary cases of melioidosis and the environments (soil and water) were obtained from stock cultures of previous studies and were phylogenetically characterized by multilocus sequence typing (ST). The susceptibility to five antibiotics, namely meropenem (MEM), imipenem, ceftazidime (CAZ), cotrimoxazole (SXT), and co-amoxiclav (AMC), recommended in both acute and eradication phases of melioidosis treatment were tested using minimum inhibitory concentration antibiotics susceptibility test.
Results: Majority of isolates were susceptible to all antibiotics tested while few resistant strains to MEM, SXT, CAZ, and AMC were observed. Statistically significant association was found between resistance to MEM and the veterinary clinical isolates (p<0.05). The likelihood of resistance to MEM was significantly higher among the novel ST 1130 isolates found in veterinary cases as compared to others.
Conclusion: The resistance to MEM and SXT appeared to be higher among veterinary isolates, and the novel ST 1130 was more likely to be resistant to MEM as compared to others.
Fulltext Association of diabetes-related self-care activities with glycemic control of patients with type 2 diabetes in Pakistan

Bukhsh A, Khan TM, Nawaz MS, Ahmed HS, Chan KG, Lee LH, et al.

Patient Prefer Adherence, 2018;12:2377-2385.
PMID: 30519003 DOI: 10.2147/PPA.S177314

Objective: Association of various self-care activities on glycemic control of people with diabetes (PWD) in Pakistan is yet to be explored. The current study aimed to evaluate the association of various diabetes-related self-care activities with glycated hemoglobin (HbA1c) levels and to examine the predictive relationship of patients' demographic variables with their self-care activities.

Patients and methods: A cross-sectional study was conducted on adult PWD (N=218) who were diagnosed with type 2 diabetes mellitus of at least 1 year duration. Self-care activities were examined by using the Urdu version of Diabetes Self-management Questionnaire. Linear regression analysis was conducted to examine the significant predictors for diabetes-related self-care activities and glycemic control.

Results: Mean age of the patients was 50.77±13.3 years. Poor glycemic control (HbA1c $7%) was observed in majority of the patients (83%). Linear regression analysis revealed that glucose management (β=-0.44; 95% CI -0.438, -0.209; P<0.001) was the strongest predictor for low levels of patients' HbA1c, followed by dietary control (β=-0.19; 95% CI -0.248, -0.018; P=0.024) and physical activity (β=-0.17; 95% CI -0.165, -0.023; P=0.010), respectively. Linear regression analysis showed that use of oral hypoglycemic agents only (β=-0.218; 95% CI -0.956, -0.200; P=0.003) and higher education level (β=0.204; 95% CI 0.138, 0.777; P=0.005) were significant predictors for higher scores of patients' self-care activities.

Conclusion: The findings support that PWD having better self-reported self-care activities achieve better glycemic control. Patients' self-care activities should be monitored on a regular basis, especially for those who are at risk of poor glycemic control.
Fulltext Development of a NS2B/NS3 protease inhibition assay using AlphaScreen® beads for screening of anti-dengue activities

Abduraman MA, Hariono M, Yusof R, Rahman NA, Wahab HA, Tan ML

Heliyon, 2018 Dec;4(12):e01023.
PMID: 30560214 DOI: 10.1016/j.heliyon.2018.e01023

Background: Dengue infection is an endemic infectious disease and it can lead to dengue fever, dengue hemorrhagic fever, and/or dengue shock syndromes. Dengue NS2B/NS3 protease complex is essential for viral replication and is a primary target for anti-dengue drug development. In this study, a NS2B/NS3 protease inhibition assay was developed using AlphaScreen® beads and was used to screen compounds for their protease inhibition activities.
Methods: The assay system utilized a known NS2B/NS3 peptide substrate, a recombinant of NS2B/NS3 protease with proprietary StrepTactin® donor and nickel chelate acceptor beads in 384-well format.
Results: The optimized assay to screen for NS2B/NS3 protease inhibitors was demonstrated to be potentially useful with reasonable z' factor, coefficient variance and signal to background ratio. However, screening of synthesized thioguanine derivatives using the optimized AlphaScreen® assay revealed weak NS2B/NS3 inhibition activities.
Conclusion: The AlphaScreen® assay to screen for NS2B/NS3 protease inhibitors is potentially applicable for high throughput screening.
Fulltext A Theoretical Study of Surface Mode Propagation with a Guiding Layer of GaN/Sapphire Hetero-Structure in Liquid Medium

Mohd Razip Wee MF, Jaafar MM, Faiz MS, Dee CF, Yeop Majlis B

Biosensors (Basel), 2018 Dec 05;8(4).
PMID: 30563159 DOI: 10.3390/bios8040124

Gallium Nitride (GaN) is considered as the second most popular semiconductor material in industry after silicon. This is due to its wide applications encompassing Light Emitting Diode (LED) and power electronics. In addition, its piezoelectric properties are fascinating to be explored as electromechanical material for the development of diverse microelectromechanical systems (MEMS) application. In this article, we conducted a theoretical study concerning surface mode propagation, especially Rayleigh and Sezawa mode in the layered GaN/sapphire structure with the presence of various guiding layers. It is demonstrated that the increase in thickness of guiding layer will decrease the phase velocities of surface mode depending on the material properties of the layer. In addition, the Q-factor value indicating the resonance properties of surface mode appeared to be affected with the presence of fluid domain, particularly in the Rayleigh mode. Meanwhile, the peak for Sezawa mode shows the highest Q factor and is not altered by the presence of fluid. Based on these theoretical results using the finite element method, it could contribute to the development of a GaN-based device to generate surface acoustic wave, especially in Sezawa mode which could be useful in acoustophoresis, lab on-chip and microfluidics applications.
Facile synthesis of GO and g-C3N4 nanosheets encapsulated magnetite ternary nanocomposite for superior photocatalytic degradation of phenol

Rehman GU, Tahir M, Goh PS, Ismail AF, Samavati A, Zulhairun AK, et al.

Environ Pollut, 2019 Oct;253:1066-1078.
PMID: 31434184 DOI: 10.1016/j.envpol.2019.07.013

In this study, the synthesis of Fe3O4@GO@g-C3N4 ternary nanocomposite for enhanced photocatalytic degradation of phenol has been investigated. The surface modification of Fe3O4 was performed through layer-by-layer electrostatic deposition meanwhile the heterojunction structure of ternary nanocomposite was obtained through sonicated assisted hydrothermal method. The photocatalysts were characterized for their crystallinity, surface morphology, chemical functionalities, and band gap energy. The Fe3O4@GO@g-C3N4 ternary nanocomposite achieved phenol degradation of ∼97%, which was significantly higher than that of Fe3O4@GO (∼75%) and Fe3O4 (∼62%). The enhanced photoactivity was due to the efficient charge carrier separation and desired band structure. The photocatalytic performance was further enhanced with the addition of hydrogen peroxide, in which phenol degradation up to 100% was achieved in 2 h irradiation time. The findings revealed that operating parameters have significant influences on the photocatalytic activities. It was found that lower phenol concentration promoted higher activity. In this study, 0.3 g of Fe3O4@GO@g-C3N4 was found to be the optimized photocatalyst for phenol degradation. At the optimized condition, the reaction rate constant was reported as 6.96 × 10-3 min-1. The ternary photocatalyst showed excellent recyclability in three consecutive cycles, which confirmed the stability of this ternary nanocomposite for degradation applications.
Fulltext Real-Time Smart-Digital Stethoscope System for Heart Diseases Monitoring

Chowdhury MEH, Khandakar A, Alzoubi K, Mansoor S, M Tahir A, Reaz MBI, et al.

Sensors (Basel), 2019 Jun 20;19(12).
PMID: 31226869 DOI: 10.3390/s19122781

One of the major causes of death all over the world is heart disease or cardiac dysfunction. These diseases could be identified easily with the variations in the sound produced due to the heart activity. These sophisticated auscultations need important clinical experience and concentrated listening skills. Therefore, there is an unmet need for a portable system for the early detection of cardiac illnesses. This paper proposes a prototype model of a smart digital-stethoscope system to monitor patient's heart sounds and diagnose any abnormality in a real-time manner. This system consists of two subsystems that communicate wirelessly using Bluetooth low energy technology: A portable digital stethoscope subsystem, and a computer-based decision-making subsystem. The portable subsystem captures the heart sounds of the patient, filters and digitizes, and sends the captured heart sounds to a personal computer wirelessly to visualize the heart sounds and for further processing to make a decision if the heart sounds are normal or abnormal. Twenty-seven t-domain, f-domain, and Mel frequency cepstral coefficients (MFCC) features were used to train a public database to identify the best-performing algorithm for classifying abnormal and normal heart sound (HS). The hyper parameter optimization, along with and without a feature reduction method, was tested to improve accuracy. The cost-adjusted optimized ensemble algorithm can produce 97% and 88% accuracy of classifying abnormal and normal HS, respectively.
An Electrochemical Sandwich Immunosensor for the Detection of HER2 using Antibody-Conjugated PbS Quantum Dot as a label

Lah ZMANH, Ahmad SAA, Zaini MS, Kamarudin MA

J Pharm Biomed Anal, 2019 Sep 10;174:608-617.
PMID: 31265987 DOI: 10.1016/j.jpba.2019.06.024

A facile electrochemical sandwich immunosensor for the detection of a breast cancer biomarker, the human epidermal growth factor receptor 2 (HER2), was designed, using lead sulfide quantum dots-conjugated secondary HER2 antibody (Ab2-PbS QDs) as a label. Using Ab2-PbS QDs in the development of electrochemical immunoassays leads to many advantages such as straightforward synthesis and well-defined stripping signal of Pb(II) through acid dissolution, which in turn yields better sensing performance for the sandwiched immunosensor. In the bioconjugation of PbS QDs, the available amine and hydroxyl groups from secondary anti-HER2 and capped PbS QDs were bound covalently together via carbonyldiimidazole (CDI) acting as a linker. In order to quantify the biomarker, SWV signal was obtained, where the Pb2+ ions after acid dissolution in HCl was detected. The plated mercury film SPCE was also detected in situ. Under optimal conditions, HER2 was detected in a linear range from 1-100 ng/mL with a limit of detection of 0.28 ng/mL. The measures of satisfactory recoveries were 91.3% to 104.3% for the spiked samples, displaying high selectivity. Therefore, this method can be applied to determine HER2 in human serum.
A feasibility of simulation-based exercise programme for overweight adult in higher learning institutions

Nik Yahya NSR, Jamaludin FIC, Firdaus MKZH, Che Hasan MK

Enferm Clin, 2019 09;29 Suppl 2:521-527.
PMID: 31281005 DOI: 10.1016/j.enfcli.2019.04.079

OBJECTIVE: This study was conducted to evaluate the feasibility of simulation-based exercise programme among overweight adult in higher learning institutes.
METHOD: A quasi-randomized controlled trial was conducted recruiting students from two different higher learning institutions in Kuantan, Pahang, Malaysia. Students are selected after fulfilling the criteria such as body mass index (BMI) of ≥23kg/m2, no chronic diseases that may influence by exercise, no significant changes in body weight within two months and not taking any medications or supplements. One institution was purposely chosen as a simulation-based group and another one control group. In the simulation-based group, participants were given a booklet and CD to do aerobic and resistance exercise for a minimum of 25min per day, three times a week for 10 weeks. No exercise was given to the control group. Participants were measured with the International Physical Activity Questionnaire (IPAQ), BMI, waist circumference (WC), body fat percentage before and after 10 weeks of simulation-based exercise.
RESULTS: A total of 52 (control: 25, simulation-based: 27) participants involved in the study. There was no baseline characteristics difference between the two groups (p>0.005). All 27 participants in the simulation-based group reported performing the exercise based on the recommendation. The retention rate at three months was 100%. No adverse events were reported throughout the study. Better outcomes (p<0.001) were reported among participants in the simulation-based group for BMI, WC and body fat percentage.
CONCLUSIONS: The findings of this study indicate that the simulation-based exercise programme may be feasible for an overweight adult in higher learning institutes. As a feasibility study this is not powered to detect significant differences on the outcomes. However, participants reported positive views towards the recommended exercise with significant improvements in body mass index, body fat percentage and reduced the waist circumference.
Supported liquid membrane extraction of nickel using stable composite SPEEK/PVDF support impregnated with a sustainable liquid membrane

Sulaiman RNR, Jusoh N, Othman N, Noah NFM, Rosly MB, Rahman HA

J Hazard Mater, 2019 12 15;380:120895.
PMID: 31351388 DOI: 10.1016/j.jhazmat.2019.120895

A sustainable and stable supported liquid membrane (SLM) extraction of nickel was developed via impregnation of sustainable liquid membrane in the composite membrane support consisting of polyvinylidene fluoride (PVDF) and sulfonated poly (ether ether ketone) (SPEEK). Bis-2-ethylhexyl phosphate (D2EHPA), 1-octanol, refined palm oil and sulfuric acid were employed as extractant, synergist extractant, diluent and strippant, respectively. Variables studied including effect of refined palm oil compositions as well as the configurations and thicknesses of SPEEK. Lifespan of SLM was evaluated by recycling the composite membrane support. Results revealed that upon using 100% refined palm oil, about 100% of nickel was extracted and recovered in 10 and 14 h, respectively. Composite SPEEK/PVDF stabilized SLM by reducing liquid membrane loss from 47 to 23% upon applying SPEEK at the feed side of PVDF support. High permeability and flux values were obtained at 9.26 x 10-4 cms-1 and 6.48 x 10-7 molcm-2s-1 when increasing SPEEK thickness from 0.025 to 0.055 mm, respectively. The lifespan of SLM was extended up to ninth cycles with low weight loss percentage of the impregnated composite membrane (8%). In conclusion, the SPEEK/PVDF impregnated with refined palm oil has improved the stability of SLM extraction of nickel ions from industrial wastewater.
Fulltext Spinopelvic Fixation Supplemented With Gullwing Plate for Multiplanar Sacral Fracture With Spinopelvic Dissociation: A Case Series With Short Term Follow Up

Mohd Asihin MA, Bajuri MY, Ahmad AR, Ganaisan PK, Fazir M, Salim AA

Front Surg, 2019;6:42.
PMID: 31380389 DOI: 10.3389/fsurg.2019.00042

We describe a series of three patients who sustained multiplanar sacral fracture with spinopelvic dissociation treated with bilateral triangle osteosynthesis supplemented with a gullwing plate. Multiplanar sacral fracture causes the sacrum to divide into two parts which in severe cases, fracture displacement results in neurological injury. Spinopelvic fixation supplemented with a gullwing plate surgical treatment is still a viable option with an acceptable outcome. The average waiting time prior to surgery is 3 weeks.
Zinc(II) salphen complex-based fluorescence optical sensor for biogenic amine detection

Sahudin MA, Su'ait MS, Tan LL, Lee YH, Abd Karim NH

Anal Bioanal Chem, 2019 Sep;411(24):6449-6461.
PMID: 31392436 DOI: 10.1007/s00216-019-02025-4

Biogenic amines have attracted interest among researchers because of their importance as biomarkers in determining the quality of food freshness in the food industry. A rapid and simple technique that is able to detect biogenic amines is needed. In this work, a new optical sensing material for one of the biogenic amines, histamine, based on a new zinc(II) salphen complex was developed. The binding of zinc(II) complexes without an electron-withdrawing group (complex 1) and with electron-withdrawing groups (F, complex 2; Cl, complex 3) to histamine resulted in enhancement of fluorescence. All complexes exhibited high affinity for histamine [binding constant of (7.14 ± 0.80) × 104, (3.33 ± 0.03) × 105, and (2.35 ± 0.14) × 105 M-1, respectively]. Complex 2 was chosen as the sensing material for further development of an optical sensor for biogenic amines in the following step since it displayed enhanced optical properties in comparison with complexes 1 and 3. The optical sensor for biogenic amines used silica microparticles as the immobilisation support and histamine as the analyte. The optical sensor had a limit of detection for histamine of 4.4 × 10-12 M, with a linear working range between 1.0 × 10-11 and 1.0 × 10-6 M (R2 = 0.9844). The sensor showed good reproducibility, with a low relative standard deviation (5.5 %). In addition, the sensor exhibited good selectivity towards histamine and cadaverine over other amines, such as 1,2-phenylenediamine, triethylamine, and trimethylamine. Recovery and real sample studies suggested that complex 2 could be a promising biogenic amine optical sensing material that can be applied in the food industry, especially in controlling the safety of food for it to remain fresh and healthy for consumption.
Manganese disulfide-silicon dioxide nano-material: Synthesis, characterization, photocatalytic, antioxidant and antimicrobial studies

Ashraf MA, Peng WX, Fakhri A, Hosseini M, Kamyab H, Chelliapan S

J. Photochem. Photobiol. B, Biol., 2019 Sep;198:111579.
PMID: 31401316 DOI: 10.1016/j.jphotobiol.2019.111579

The sol-gel/ultrasonically rout produced the novel MnS2-SiO2 nano-hetero-photocatalysts with the various ratio of MnS2. Prepared nano-catalyst were investigated in the photo-degradation of methylene blue under UV light illumination. Structural and optical attributes of as-prepared nano-catalysts were evaluated by X-ray diffraction and photoelectron spectroscopy. The morphological were studied by scanning electron microscopy-EDS, and dynamic light scattering. The diffuse reflectance spectroscopy was applied to examine the band gap energy. The Eg values of SiO2, MnS2-SiO2-0, MnS2-SiO2-1, and MnS2-SiO2-2 nanocomposites are 6.51, 3.85, 3.17, and 2.67 eV, respectively. The particle size of the SiO2 and MnS2-SiO2-1 nanocomposites were 100.0, and 65.0 nm, respectively. The crystallite size values of MnS2-SiO2-1 were 52.21 nm, and 2.9 eV, respectively. MnS2-SiO2 nano-photocatalyst was recognized as the optimum sample by degrading 96.1% of methylene blue from water. Moreover, the influence of pH of the solution, and contact time as decisive factors on the photo-degradation activity were investigated in this project. The optimum data for pH and time were found 9 and 60 min, respectively. The photo-degradation capacity of MnS2-SiO2-2 is improved (96.1%) due to the low band gap was found from UV-vis DRS. The antimicrobial data of MnS2-SiO2 were studied and demonstrated that the MnS2-SiO2 has fungicidal and bactericidal attributes.
Fulltext Regulation of terpenoid biosynthesis by miRNA in Persicaria minor induced by Fusarium oxysporum

Samad AFA, Rahnamaie-Tajadod R, Sajad M, Jani J, Murad AMA, Noor NM, et al.

BMC Genomics, 2019 07 16;20(1):586.
PMID: 31311515 DOI: 10.1186/s12864-019-5954-0

BACKGROUND: Persicaria minor (kesum) is an herbaceous plant with a high level of secondary metabolite compounds, particularly terpenoids. These terpenoid compounds have well-established roles in the pharmaceutical and food industries. Although the terpenoids of P. minor have been studied thoroughly, the involvement of microRNA (miRNA) in terpenoid regulation remains poorly understood and needs to be explored. In this study, P. minor plants were inoculated with the pathogenic fungus Fusarium oxysporum for terpenoid induction.
RESULT: SPME GC-MS analysis showed the highest terpenoid accumulation on the 6th day post-inoculation (dpi) compared to the other treatment time points (0 dpi, 3 dpi, and 9 dpi). Among the increased terpenoid compounds, α-cedrene, valencene and β-bisabolene were prominent. P. minor inoculated for 6 days was selected for miRNA library construction using next generation sequencing. Differential gene expression analysis showed that 58 miRNAs belonging to 30 families had significantly altered regulation.
Among these 58 differentially expressed genes (DEGs), 27 [corrected] miRNAs were upregulated, whereas 31 [corrected] miRNAs were downregulated. Two putative novel pre-miRNAs were identified and validated through reverse transcriptase PCR. Prediction of target transcripts potentially involved in the mevalonate pathway (MVA) was carried out by psRobot software, resulting in four miRNAs: pmi-miR530, pmi-miR6173, pmi-miR6300 and a novel miRNA, pmi-Nov_13. In addition, two miRNAs, miR396a and miR398f/g, were predicted to have their target transcripts in the non-mevalonate pathway (MEP). In addition, a novel miRNA, pmi-Nov_12, was identified to have a target gene involved in green leaf volatile (GLV) biosynthesis. RT-qPCR analysis showed that pmi-miR6173, pmi-miR6300 and pmi-nov_13 were downregulated, while miR396a and miR398f/g were upregulated. Pmi-miR530 showed upregulation at 9 dpi, and dynamic expression was observed for pmi-nov_12. Pmi-6300 and pmi-miR396a cleavage sites were detected through degradome sequence analysis. Furthermore, the relationship between miRNA metabolites and mRNA metabolites was validated using correlation analysis.
CONCLUSION: Our findings suggest that six studied miRNAs post-transcriptionally regulate terpenoid biosynthesis in P. minor. This regulatory behaviour of miRNAs has potential as a genetic tool to regulate terpenoid biosynthesis in P. minor.
Fulltext Investigation of Surface Plasmon Resonance (SPR) in MoS2- and WS2-Protected Titanium Side-Polished Optical Fiber as a Humidity Sensor

Zakaria R, Zainuddin NAM, Leong TC, Rosli R, Rusdi MF, Harun SW, et al.

Micromachines (Basel), 2019 Jul 11;10(7).
PMID: 31336745 DOI: 10.3390/mi10070465

In this paper, we report the effects of a side-polished fiber (SPF) coated with titanium (Ti) films in different thicknesses, namely 5 nm, 13 nm, and 36 nm, protected by a thin layer of transition metal dichalcogenides (TMDCs) such as molybdenum disulfide (MoS2) and tungsten disulfide (WS2), which provide ultra-sensitive sensor-based surface plasmon resonance (SPR) covering from the visible to mid-infrared region. The SPF deposited with Ti exhibits strong evanescent field interaction with the MoS2 and WS2, and good optical absorption, hence resulting in high-sensitivity performance. Incremental increases in the thickness of the Ti layer contribute to the enhancement of the intensity of transmission with redshift and broad spectra. The findings show that the optimum thickness of Ti with 36 nm combined with MoS2 causes weak redshifts of the longitudinal localized surface plasmon resonance (LSPR) mode, while the same thickness of Ti with WS2 causes large blueshifts. The redshifts are possibly due to a reduced plasmon-coupling effect with the excitonic region of MoS2. The observed blueshifts of the LSPR peak position are possibly due to surface modification between WS2 and Ti. Changing the relative humidity from 58% to 88% only elicited a response in Ti/MoS2. Thus, MoS2 shows more sensitivity on 36-nm thickness of Ti compared with WS2. Therefore, the proposed fiber-optic sensor with integration of 2D materials is capable of measuring humidity in any environment.
Fulltext Morphological Diversity of Gracilaria blodgettii Harvey 1853 (Gracilariaceae, Rhodophyta) from Sarawak, Malaysian Borneo

Hassan R, Othman MNA, Harith MN, Md Sah ASR

Scientifica (Cairo), 2019;2019:3430968.
PMID: 31355044 DOI: 10.1155/2019/3430968

Gracilaria red algae are notable for their economic importance as agrophytes, sold as salad vegetable, and used as the base for selected food and nonalcoholic beverages. A wild population of Gracilaria exists in coastal areas of Sarawak, Malaysian Borneo, but there is only limited knowledge on species diversity and its abundance leaving the untapped economic potential of this resource. This study was carried out to determine diversity of wild Gracilaria populations in Lawas, Santubong, and Asajaya, Sarawak, using the combination of morphological character examination and 5' region of the mitochondrial cytochrome c oxidase 1 (CO1-5P) gene analysis. Identification of the species using morphological characters revealed three species, namely, Gracilaria changii, G. blodgettii, and G. arcuata, had been collected from the sampling sites. However, based on 672 bp CO1-5P gene sequence analysis, all the three species were identified as G. blodgettii; besides, low genetic divergence values (0.17%-0.34%) were scored between samples in this study with the same species in GenBank. In the phylogenetic trees, all samples in this study group together with other G. blodgettii have high bootstrap values; thus, this species is monophyletic. This study implies that species identification of Gracilaria and other seagrass taxa which have a phenotypic plasticity problem should include the CO1-5P gene analysis as it is a reliable gene marker for species diversity assessment.
Fulltext Correction to: Regulation of terpenoid biosynthesis by miRNA in Persicaria minor induced by Fusarium oxysporum

Samad AFA, Rahnamaie-Tajadod R, Sajad M, Jani J, Murad AMA, Noor NM, et al.

BMC Genomics, 2019 08 01;20(1):627.
PMID: 31370802 DOI: 10.1186/s12864-019-5994-5

Following publication of the original article [1], the authors reported a number of errors, which are listed in this Correction article. The corrections are marked in bold.

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