Browse publications by year: 2016

  1. Hameed YT, Idris A, Hussain SA, Abdullah N
    J Environ Manage, 2016 Dec 15;184(Pt 3):494-503.
    PMID: 27789092 DOI: 10.1016/j.jenvman.2016.10.033
    Chemical composition and flocculation efficiency were investigated for a commercially produced tannin - based coagulant and flocculant (Tanfloc). The results of Fourier Transform Infrared Spectroscopy (FTIR) and Energy Dispersive Spectroscopy (EDX) confirmed what claimed about the chemical composition of Tanfloc. For moderate polluted municipal wastewater investigated in both jar test and pilot plant, Tanfloc showed high turbidity removal efficiency of approximately 90%, while removal efficiencies of BOD5 and COD were around 60%. According to floc size distribution, Tanfloc was able to show distinct performance compared to Polyaluminum chloride (PAC). While 90% of flocs produced by Tanfloc were smaller than 144 micron, they were smaller than 96 micron for PAC. Practically, zeta potential measurement showed the cationic nature of Tanfloc and suggested coincidence of charge neutralization and another flocculation mechanism (bridging or patch flocculation). Sludge Volumetric Index (SVI) measurements were in agreement with the numbers found in the literature, and they were less than 160 mL/g. Calcium cation as flocculation aid showed significant improvement of flocculation efficiency compared to other cations. Finally Tanfloc showed competing performance compared to PAC in terms of turbidity, BOD5 and COD removal, floc size and sludge characteristics.
    MeSH terms: Aluminum Hydroxide/chemistry*; Flocculation; Sewage/chemistry; Tannins/chemistry*; Waste Disposal, Fluid/methods; Water Pollutants, Chemical/chemistry*; Waste Water/chemistry*
  2. Chan JY, Ooi EH
    Cryobiology, 2016 12;73(3):304-315.
    PMID: 27789380 DOI: 10.1016/j.cryobiol.2016.10.006
    Advancement in biomedical simulation and imaging modality have catalysed the development of in silico predictive models for cryoablation. However, one of the main challenges in ensuring the accuracy of the model prediction is the use of proper thermal and biophysical properties of the patient. These properties are difficult to measure clinically and thus, represent significant uncertainty that can affect the model prediction. Motivated by this, a sensitivity analysis is carried out to identify the model parameters that have the most significant impact on the lesion size during cryoablation. The study is initially carried out using the Morris method to screen for the most dominant parameters. Once determined, analysis of variance (ANOVA) is performed to quantitatively rank the order of importance of each parameter and their interactions. Results from the sensitivity analysis revealed that blood perfusion, water transport and ice nucleation parameters are critical in predicting the lesion size, suggesting that the acquisition of these parameters should be prioritised to ensure the accuracy of the model prediction.
    MeSH terms: Biophysics*; Computer Simulation; Cryosurgery*; Humans; Models, Biological*
  3. Bong CH, Lau TL, Ab Ghani A, Chan NW
    Water Sci Technol, 2016 Oct;74(8):1876-1884.
    PMID: 27789888
    The understanding of how the sediment deposit thickness influences the incipient motion characteristic is still lacking in the literature. Hence, the current study aims to determine the effect of sediment deposition thickness on the critical velocity for incipient motion. An incipient motion experiment was conducted in a rigid boundary rectangular flume of 0.6 m width with varying sediment deposition thickness. Findings from the experiment revealed that the densimetric Froude number has a logarithmic relationship with both the thickness ratios ts/d and ts/y0 (ts: sediment deposit thickness; d: grain size; y0: normal flow depth). Multiple linear regression analysis was performed using the data from the current study to develop a new critical velocity equation by incorporating thickness ratios into the equation. The new equation can be used to predict critical velocity for incipient motion for both loose and rigid boundary conditions. The new critical velocity equation is an attempt toward unifying the equations for both rigid and loose boundary conditions.
    MeSH terms: Environmental Monitoring/methods*; Water Movements*; Linear Models; Geologic Sediments/analysis*
  4. Bhagat V, Haque M, Bin Abu Bakar YI, Husain R, Khairi CM
    Adv Med Educ Pract, 2016;7:575-584.
    PMID: 27790052
    Emotional maturity (EM) is defined as the ability of an individual to respond to situations, control emotions, and behave in an adult manner when dealing with others. EM is associated with adult learning skill, which is an important aspect of professional development as stated in the principles of andragogy. These principles are basically a characteristic feature of adult learning, which is defined as "the entire range of formal, non-formal, and informal learning activities that are undertaken by adults after an initial education and training, which result in the acquisition of new knowledge and skills". The purpose of this study is to find out the influence of EM on adult learning among Years I and II medical students of Universiti Sultan Zainal Abidin (UniSZA). The study population included preclinical medical students of UniSZA from Years I and II of the academic session 2015/2016. The convenient sampling technique was used to select the sample. Data were collected using "EM scale" to evaluate emotional level and adult learning scale to assess the adult learning scores. Out of 120 questionnaires, only six response sheets were not complete and the remaining 114 (95%) were complete. Among the study participants, 23.7% (27) and 76.3% (87) were males and females, respectively. The data were then compiled and analyzed using SPSS Version 22. The Pearson's correlation method was used to find the significance of their association. The results revealed a significant correlation between EM and adult learning scores (r=0.40, p<0.001). Thus, the study result supports the prediction, and based on the current findings, it can be concluded that there is a significant correlation between EM and adult learning and it has an effect on the students. Medical faculty members should give more emphasis on these aspects to produce health professionals. Henceforward, researchers can expect with optimism that the country will create more rational medical doctors.
    MeSH terms: Adult; Emotions; Eugenol; Faculty, Medical; Female; Humans; Male; Physicians; Surveys and Questionnaires; Students, Medical; Zinc Oxide
  5. Yong D, Tee KK, Yin WF, Chan KG
    Front Microbiol, 2016;7:1606.
    PMID: 27790203
    To date, information on plasmid analysis in Pandoraea spp. is scarce. To address the gap of knowledge on this, the complete sequences of eight plasmids from Pandoraea spp. namely Pandoraea faecigallinarum DSM 23572(T) (pPF72-1, pPF72-2), Pandoraea oxalativorans DSM 23570(T) (pPO70-1, pPO70-2, pPO70-3, pPO70-4), Pandoraea vervacti NS15 (pPV15) and Pandoraea apista DSM 16535(T) (pPA35) were studied for the first time in this study. The information on plasmid sequences in Pandoraea spp. is useful as the sequences did not match any known plasmid sequence deposited in public databases. Replication genes were not identified in some plasmids, a situation that has led to the possibility of host interaction involvement. Some plasmids were also void of par genes and intriguingly, repA gene was also not discovered in these plasmids. This further leads to the hypothesis of host-plasmid interaction. Plasmid stabilization/stability protein-encoding genes were observed in some plasmids but were not established for participating in plasmid segregation. Toxin-antitoxin systems MazEF, VapBC, RelBE, YgiT-MqsR, HigBA, and ParDE were identified across the plasmids and their presence would improve plasmid maintenance. Conjugation genes were identified portraying the conjugation ability amongst Pandoraea plasmids. Additionally, we found a shared region amongst some of the plasmids that consists of conjugation genes. The identification of genes involved in replication, segregation, toxin-antitoxin systems and conjugation, would aid the design of drugs to prevent the survival or transmission of plasmids carrying pathogenic properties. Additionally, genes conferring virulence and antibiotic resistance were identified amongst the plasmids. The observed features in the plasmids shed light on the Pandoraea spp. as opportunistic pathogens.
    MeSH terms: Drug Resistance, Microbial; Plasmids; Virulence; Burkholderiaceae
  6. Randhawa SS, Kwan AK, Chiu CK, Chan CY, Kwan MK
    Asian Spine J, 2016 Oct;10(5):945-949.
    PMID: 27790326
    We report two patients with cauda equina syndrome (CES) secondary to L5 giant cell tumour (GCT) who achieved good neurological recovery after treatment with denosumab without surgery. The first patient was a 26-year-old man with L5 GCT causing CES who regained bowel and urinary control, muscle power improvement from grade 2 to grade 4 and Oswestry disability index (ODI) improvement from 48 to 23 after denosumab treatment. The second patient was a 25-year-old woman with L5 GCT causing CES who regained bowel and urinary control, muscle power improvement from grade 0 to grade 4 and ODI improvement from 42 to 20 after denosumab treatment. The usage of denosumab in the treatment of patients with CES due to GCT allows potential neurological recovery without any surgical intervention. If surgery is not contraindicated, more time is obtained to prepare the patient preoperatively to attain safer surgery and to achieve complete tumour clearance.
    MeSH terms: Denosumab; Adult; Female; Giant Cell Tumors; Humans; Intestines; Male; Neoplasms
  7. Fadzilah N, Azman M, See GB
    J Clin Diagn Res, 2016 Sep;10(9):MD01-MD03.
    PMID: 27790477
    Lingual hamartoma is a rare finding of congenital midline posterior tongue mass. The lesion may be seen as a single anomaly or maybe associated with syndrome especially the Oral Facial Digital Syndrome (OFDS). Here, we report an otherwise normal and healthy two-month-old boy with a congenital midline base of tongue mass presented with snoring and episodic vomiting since the age of 1 month. Tumour excision from the area of foramen of caecum recovered a pinkish pedunculated tumour. Histopathology examination confirmed the diagnosis of leiomyomatous lingual hamartoma. Differential diagnosis, especially for midline tongue mass and other paediatric tongue lesions are discussed. We also discuss the epidemiology, histopathologic features, treatment and prognosis of lingual hamartoma based on the literature review.
    MeSH terms: Cecum; Child; Diagnosis, Differential; Hamartoma; Humans; Leiomyoma; Male; Orofaciodigital Syndromes; Prognosis; Snoring; Tongue; Tongue Neoplasms; Vomiting
  8. Veerabhadrappa SK, Chandrappa PR, Patil S, Roodmal SY, Kumarswamy A, Chappi MK
    J Clin Diagn Res, 2016 Sep;10(9):ZC24-ZC27.
    PMID: 27790574
    Psychiatric diseases like anxiety, depression, schizophrenia and bipolar disorders are increasing at an alarming rate. These diseases can affect the quantity and quality of saliva leading to multiple oral diseases. Although many researchers have evaluated xerostomia in general population, its prevalence is not been assessed in patients suffering from different psychological disorders.
  9. Nurul AH, Shamsul BM, Hassim IN
    Work, 2016 Oct 28.
    PMID: 27792033
    Steel manufacturing produces dust, fumes, and pollutant gases that may give adverse health effects to the respiratory function of workers. Improper occupational hygiene practice in the workplace will affect both workers wellbeing and productivity.
  10. Meganathan P, Fu JY
    Int J Mol Sci, 2016 Oct 26;17(11).
    PMID: 27792171
    Vitamin E has been recognized as an essential vitamin since their discovery in 1922. Although the functions of tocopherols are well established, tocotrienols have been the unsung heroes of vitamin E. Due to their structural differences, tocotrienols were reported to exert distinctive properties compared to tocopherols. While most vegetable oils contain higher amount of tocopherols, tocotrienols were found abundantly in palm oil. Nature has made palm vitamin E to contain up to 70% of total tocotrienols, among which alpha-, gamma- and delta-tocotrienols are the major constituents. Recent advancements have shown their biological properties in conferring protection against cancer, cardiovascular diseases, neurodegeneration, oxidative stress and immune regulation. Preclinical results of these physiological functions were translated into clinical trials gaining global attention. This review will discuss in detail the evidence in human studies to date in terms of efficacy, population, disease state and bioavailability. The review will serve as a platform to pave the future direction for tocotrienols in clinical settings.
    MeSH terms: Antineoplastic Agents/pharmacokinetics; Antineoplastic Agents/pharmacology; Antineoplastic Agents/therapeutic use; Cardiovascular Diseases/drug therapy; Cognition/drug effects; Humans; Immunologic Factors/pharmacokinetics; Immunologic Factors/pharmacology; Immunologic Factors/therapeutic use; Neoplasms/drug therapy; Radiation-Protective Agents/pharmacokinetics; Radiation-Protective Agents/pharmacology; Radiation-Protective Agents/therapeutic use; Vitamins/pharmacokinetics; Vitamins/pharmacology; Vitamins/therapeutic use*; Neuroprotective Agents/pharmacokinetics; Neuroprotective Agents/pharmacology; Neuroprotective Agents/therapeutic use; Tocotrienols/pharmacokinetics; Tocotrienols/pharmacology; Tocotrienols/therapeutic use*
  11. Hang CY, Moriya S, Ogawa S, Parhar IS
    PLoS One, 2016;11(10):e0165535.
    PMID: 27792783 DOI: 10.1371/journal.pone.0165535
    Non-rod non-cone photopigments in the eyes and the brain can directly mediate non-visual functions of light in non-mammals. This was supported by our recent findings on vertebrate ancient long (VAL)-opsin photopigments encoded by the val-opsinA (valopa) and val-opsinB (valopb) genes in zebrafish. However, the physiological functions of valop isoforms remain unknown. Here, we generated valop-mutant zebrafish using CRISPR/Cas genome editing, and examined the phenotypes of loss-of-function mutants. F0 mosaic mutations and germline transmission were confirmed via targeted insertions and/or deletions in the valopa or valopb gene in F1 mutants. Based on in silico analysis, frameshift mutations converted VAL-opsin proteins to non-functional truncated forms with pre-mature stop codons. Most F1 eggs or embryos from F0 female valopa/b mutants showed either no or only partial chorion elevation, and the eggs or embryos died within 26 hour-post-fertilization. However, most F1 embryos from F0 male valopa mutant developed but hatched late compared to wild-type embryos, which hatched at 4 day-post-fertilization. Late-hatched F1 offspring included wild-type and mutants, indicating the parental effects of valop knockout. This study shows valop gene knockout affects chorion formation and embryonic hatching in the zebrafish.
    MeSH terms: Amino Acid Sequence; Animals; Brain/embryology; Brain/metabolism*; Chorion/growth & development*; Female; Male; Mutation; Zebrafish/embryology*; Zebrafish/genetics*; Receptors, G-Protein-Coupled/deficiency; Receptors, G-Protein-Coupled/genetics*; Receptors, G-Protein-Coupled/chemistry; Opsins/deficiency; Opsins/genetics*; Opsins/chemistry; Gene Knockout Techniques*; CRISPR-Cas Systems/genetics*
  12. Wo MC, Lim KS, Choo WY, Tan CT
    Epilepsy Res, 2016 Dec;128:6-11.
    PMID: 27792885 DOI: 10.1016/j.eplepsyres.2016.10.003
    PURPOSE: People with epilepsy (PWE) are negatively prejudiced in their ability to work. This study aimed to examine demographic, clinical and psychological factors associated with employability in PWE.

    METHODS: This study recruited epilepsy patients from a neurology clinic in Malaysia. Employability was measured using employment ratio, with a ratio ≥90% (ER90) classified as high employability. Basic demographic data such as age, gender, marital status, religion, education level and household income was collected. Clinical measures consisted of age of seizure onset, seizure frequency, type of epilepsy, aura, polytherapy, nocturnal seizures and seizure control. Psychological measures included Work Self-Determination Index (WSDI), Rosenberg Self-Esteem Scale (SES), and Multidimensional Scale of Perceived Social Support (MSPSS).

    RESULTS: Of 146 PWE, 64.4% had high employability. The participants were predominantly female (52%), Chinese (50.7%), single (50%), having tertiary education (55.5%) and focal epilepsy (72.6%). Clinically, only type of epilepsy was significantly correlated to employability of PWE. Employability of PWE was associated with ability to work (indicated by education level, work performance affected by seizures, ability to travel independently and ability to cope with stress at work) and family overprotection. The high employability group was found to have lower self-perceived stigma (ESS), higher self-determined motivation (WSDI), self-esteem (SES) and perceived social support (MSPSS), than the low employability group. Logistic regression analysis showed that tertiary education level (AOR 3.42, CI: 1.46-8.00), higher self-determination (WSDI, AOR 1.09, CI: 1.012-1.17), lower family overprotection (AOR 0.76, CI: 0.61-0.95), and generalised epilepsy (AOR 4.17, CI: 1.37-12.70) were significant predictors for higher employability in PWE.

    CONCLUSION: Ability to work (education level), clinical factor (type of epilepsy) and psychological factor (self-determined motivation and family overprotection) were important factors affecting employability in PWE.

    Study site: neurology clinic Universiti Malaya Medical Centre (UMMC)
    MeSH terms: Adult; Cross-Sectional Studies; Educational Status; Epilepsy/epidemiology*; Epilepsy/psychology*; Family/psychology; Female; Hospitals, University; Humans; Malaysia; Male; Motivation; Outpatient Clinics, Hospital; Self Concept; Social Support; Logistic Models; Social Stigma; Self Report
  13. Lee Y, Roslan R, Azizan S, Firdaus-Raih M, Ramlan EI
    BMC Bioinformatics, 2016 Oct 28;17(1):438.
    PMID: 27793081
    BACKGROUND: Biological macromolecules (DNA, RNA and proteins) are capable of processing physical or chemical inputs to generate outputs that parallel conventional Boolean logical operators. However, the design of functional modules that will enable these macromolecules to operate as synthetic molecular computing devices is challenging.

    RESULTS: Using three simple heuristics, we designed RNA sensors that can mimic the function of a seven-segment display (SSD). Ten independent and orthogonal sensors representing the numerals 0 to 9 are designed and constructed. Each sensor has its own unique oligonucleotide binding site region that is activated uniquely by a specific input. Each operator was subjected to a stringent in silico filtering. Random sensors were selected and functionally validated via ribozyme self cleavage assays that were visualized via electrophoresis.

    CONCLUSIONS: By utilising simple permutation and randomisation in the sequence design phase, we have developed functional RNA sensors thus demonstrating that even the simplest of computational methods can greatly aid the design phase for constructing functional molecular devices.

    MeSH terms: Computer Simulation; Electrophoresis, Polyacrylamide Gel; RNA/chemistry*; Reproducibility of Results; RNA, Catalytic/metabolism; Computational Biology/instrumentation*; Computational Biology/methods*
  14. Fu Y, Persson MS, Bhattacharya A, Goh SL, Stocks J, van Middelkoop M, et al.
    Syst Rev, 2016 10 28;5(1):183.
    PMID: 27793184
    BACKGROUND: The management of osteoarthritis (OA) is unsatisfactory, as most treatments are not clinically effective over placebo and most drugs have considerable side effects. On average, 75 % of the analgesic effect from OA treatments in clinical trials can be attributed to a placebo response, and this response varies greatly from patient to patient. This individual patient data (IPD) meta-analysis aims to identify placebo responders and the potential determinants of the placebo response in OA.

    METHODS: This study is undertaken in conjunction with the OA Trial Bank, an ongoing international consortium aiming to collect IPD from randomised controlled trials (RCTs) for all treatments of OA. RCTs for each treatment of OA have been systematically searched for, and authors of the relevant trials have been contacted to request the IPD. We will use the IPD of placebo-controlled RCTs held by the OA Trial Bank for this project. The IPD in placebo groups will be used to investigate the placebo response according to the minimum clinically important difference (MCID) threshold (e.g. 20 % pain reduction). Responders to placebo will be compared with non-responders to identify predictors of response. The quality of the trials will be assessed and potential determinants will be examined using multilevel logistic regression analyses.

    DISCUSSION: This study explores the varying magnitude of the placebo response and the proportion of participants that experience a clinically important placebo effect in OA RCTs. Potential determinants of the placebo response will also be investigated. These determinants may be useful for future studies as it may allow participants to be stratified into groups based on their likely response to placebo. The results of this study may also be useful for pharmaceutical companies, who could improve the design of their studies in order to separate the specific treatment from the non-specific contextual (i.e. placebo) effects.

    SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016033212.
    MeSH terms: Anti-Inflammatory Agents, Non-Steroidal/therapeutic use*; Humans; Meta-Analysis as Topic; Placebo Effect*; Randomized Controlled Trials as Topic*; Osteoarthritis, Knee/drug therapy*
  15. Miswan Z, Lukman SK, Abd Majid FA, Loke MF, Saidin S, Hermawan H
    Int J Pharm, 2016 Dec 30;515(1-2):460-466.
    PMID: 27793709 DOI: 10.1016/j.ijpharm.2016.10.056
    Active ingredients of ginsenoside, Rg1 and Re, are able to inhibit the proliferation of vascular smooth muscle cells and promote the growth of vascular endothelial cells. These capabilities are of interest for developing a novel drug-eluting stent to potentially solve the current problem of late-stent thrombosis and poor endotheliazation. Therefore, this study was aimed to incorporate ginsenoside into degradable coating of poly(lactic-co-glycolic acid) (PLGA). Drug mixture composed of ginseng extract and 10% to 50% of PLGA (xPLGA/g) was coated on electropolished stainless steel 316L substrate by using a dip coating technique. The coating was characterized principally by using attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscopy and contact angle analysis, while the drug release profile of ginsenosides Rg1 and Re was determined by using mass spectrometry at a one month immersion period. Full and homogenous coating coverage with acceptable wettability was found on the 30PLGA/g specimen. All specimens underwent initial burst release dependent on their composition. The 30PLGA/g and 50PLGA/g specimens demonstrated a controlled drug release profile having a combination of diffusion- and swelling-controlled mechanisms of PLGA. The study suggests that the 30PLGA/g coated specimen expresses an optimum composition which is seen as practicable for developing a controlled release drug-eluting stent.
    MeSH terms: Delayed-Action Preparations/chemistry; Pharmaceutical Preparations/chemistry*; Materials Testing/methods; Microscopy, Electron, Scanning/methods; Polyglycolic Acid/chemistry*; Stainless Steel/chemistry*; Spectroscopy, Fourier Transform Infrared/methods; Lactic Acid/chemistry*; Coated Materials, Biocompatible/chemistry; Ginsenosides/chemistry*; Drug-Eluting Stents; Drug Liberation
  16. Goh LC, Chitra BK, Shaariyah MM, Ng WS
    BMJ Case Rep, 2016 Oct 28;2016.
    PMID: 27793872 DOI: 10.1136/bcr-2016-217514
    Sialolithiasis is among the most common disease affecting the major salivary glands whereby the submandibular gland or its duct is affected in the majority of cases. We report a case of the surgical removal of a giant sialolith along with the submandibular gland using the transcervical approach and its clinical outcome.
    MeSH terms: Adult; Humans; Male; Radiography, Panoramic; Submandibular Gland Diseases/surgery*; Salivary Gland Calculi/surgery*
  17. Jennings CJ, Zainal N, Dahlan IM, Kay EW, Harvey BJ, Thomas W
    Anticancer Res, 2016 11;36(11):5905-5913.
    PMID: 27793915
    Malignant pleural mesothelioma (MPM) is a rare but highly aggressive malignancy most often associated with exposure to asbestos. Recent evidence points to oestrogen receptor (ER)-β having a tumour-suppressor role in MPM progression, and this raises the question of whether selective modulators of ERs could play a role in augmenting MPM therapy.
    MeSH terms: Cisplatin/administration & dosage; Humans; Mesothelioma/pathology*; Pleural Neoplasms/pathology*; Tamoxifen/administration & dosage; Tamoxifen/pharmacology*; Apoptosis/drug effects; Cyclin-Dependent Kinases/antagonists & inhibitors; Antineoplastic Agents, Hormonal/pharmacology*; Cell Line, Tumor; Cell Proliferation/drug effects*
  18. Ng KH, Cheng YW, Khan MR, Cheng CK
    J Environ Manage, 2016 Dec 15;184(Pt 3):487-493.
    PMID: 27784576 DOI: 10.1016/j.jenvman.2016.10.034
    This paper reports on the optimization of palm oil mill effluent (POME) degradation in a UV-activated-ZnO system based on central composite design (CCD) in response surface methodology (RSM). Three potential factors, viz. O2 flowrate (A), ZnO loading (B) and initial concentration of POME (C) were evaluated for the significance analysis using a 2(3) full factorial design before the optimization process. It is found that all the three main factors were significant, with contributions of 58.27% (A), 15.96% (B) and 13.85% (C), respectively, to the POME degradation. In addition, the interactions between the factors AB, AC and BC also have contributed 4.02%, 3.12% and 1.01% to the POME degradation. Subsequently, all the three factors were subjected to statistical central composite design (CCD) analysis. Quadratic models were developed and rigorously checked. A 3D-response surface was subsequently generated. Two successive validation experiments were carried out and the degradation achieved were 55.25 and 55.33%, contrasted with 52.45% for predicted degradation value.
    MeSH terms: Catalysis; Industrial Waste/analysis; Models, Theoretical*; Plant Oils*; Ultraviolet Rays*; Water Pollutants, Chemical/chemistry*; Zinc Oxide/radiation effects*; Zinc Oxide/chemistry*; Reproducibility of Results; Photochemical Processes
  19. Rajinikanth PS, Chellian J
    Int J Nanomedicine, 2016 Oct 5;11:5067-5077.
    PMID: 27785014
    The aim of this study was to develop a nanostructured lipid carrier (NLC)-based hydrogel and study its potential for the topical delivery of 5-fluorouracil (5-FU). Precirol(®) ATO 5 (glyceryl palmitostearate) and Labrasol(®) were selected as the solid and liquid lipid phases, respectively. Poloxamer 188 and Solutol(®) HS15 (polyoxyl-15-hydroxystearate) were selected as surfactants. The developed lipid formulations were dispersed in 1% Carbopol(®) 934 (poly[acrylic acid]) gel medium in order to maintain the topical application consistency. The average size, zeta potential, and polydispersity index for the 5-FU-NLC were found to be 208.32±8.21 nm, -21.82±0.40 mV, and 0.352±0.060, respectively. Transmission electron microscopy study revealed that 5-FU-NLC was <200 nm in size, with a spherical shape. In vitro drug permeation studies showed a release pattern with initial burst followed by sustained release, and the rate of 5-FU permeation was significantly improved for 5-FU-NLC gel (10.27±1.82 μg/cm(2)/h) as compared with plain 5-FU gel (2.85±1.12 μg/cm(2)/h). Further, skin retention studies showed a significant retention of 5-FU from the NLC gel (91.256±4.56 μg/cm(2)) as compared with that from the 5-FU plain gel (12.23±3.86 μg/cm(2)) in the rat skin. Skin irritation was also significantly reduced with 5-FU-NLC gel as compared with 5-FU plain gel. These results show that the prepared 5-FU-loaded NLC has high potential to improve the penetration of 5-FU through the stratum corneum, with enormous retention and with minimal skin irritation, which is the prerequisite for topically applied formulations.
    MeSH terms: Administration, Topical; Animals; Antimetabolites, Antineoplastic/administration & dosage; Chemistry, Pharmaceutical; Drug Carriers/administration & dosage; Drug Carriers/chemistry*; Erythema/metabolism; Erythema/prevention & control; Fluorouracil/administration & dosage*; Lipids/chemistry*; Male; Particle Size; Skin/drug effects*; Skin/metabolism; Skin Absorption/drug effects; Skin Absorption/radiation effects; Drug Design; Drug Delivery Systems*; Rats, Wistar; Hydrogel/chemistry*; Microscopy, Electron, Transmission; Nanostructures/chemistry*; Mice; Rats
  20. Yam MF, Tan CS, Ahmad M, Ruan S
    Am J Chin Med, 2016;44(7):1413-1439.
    PMID: 27785939
    Orthosiphon stamineus Benth. (Lamiaceae) is an important plant in traditional folk medicine that is used to treat hypertension and kidney stones. In humans, this plant has been tested as an addition regiment for antihypertensive treatment. Among the treatments for hypertension, O. stamineus had been to have diuretic and vasorelaxant effects in animal models. There is still very little information regarding the vasorelaxant effect of O. stamineus. Therefore, the present study was designed to investigate the vasorelaxant activity and mechanism of action of the fractions of O. stamineus. The vasorelaxant activity and the underlying mechanisms of the chloroform fraction of the 50% methanolic extract of O. stamineus (CF) was evaluated on thoracic aortic rings isolated from Sprague Dawley rats. CF caused relaxation of the aortic ring pre-contracted with phenylephrine in the presence and absence of endothelium, and pre-contracted with potassium chloride in endothelium-intact aortic ring. In the presence of endothelium, both indomethacin (a nonselective cyclooxygenase inhibitor) and [Formula: see text]-[1,2,4]Oxadiazolo[4,3-[Formula: see text]]quinoxalin-1-one (ODQ, selective soluble guanylate cyclase inhibitor) had a small effect on the vasorelaxation response. On the other hand, in the presence of Nω-nitro-L-arginine methyl ester (L-NAME, nitric oxide synthase inhibitor), methylene blue (cyclic guanosine monophosphate lowering agent), tetraethylammonium ([Formula: see text], nonselective calcium activator [Formula: see text] channel blocker), 4-aminopyridine (4-AP, voltage-dependent [Formula: see text] channel blocker), barium chloride ([Formula: see text], inwardly rectifying [Formula: see text] channel blocker), glibenclamide (nonspecific ATP-sensitive [Formula: see text] channel blocker), atropine (muscarinic receptor blocker) and propranolol (β-adrenergic receptor blocker), the vasorelaxant effect significantly reduced the relaxation stimulated by CF. CF was also found to be active in reducing [Formula: see text] release from the sarcoplasmic reticulum and blocking calcium channels.
    MeSH terms: Animals; Aorta, Thoracic/drug effects; Aorta, Thoracic/metabolism; Calcium Channel Blockers; Chloroform*; Chemical Fractionation; Cyclic GMP/metabolism*; Hypertension/drug therapy; Male; Phytotherapy; Nitric Oxide/metabolism*; Plant Extracts/pharmacology*; Plant Extracts/therapeutic use; Potassium/metabolism*; Sarcoplasmic Reticulum/metabolism; Vasodilation/drug effects*; Vasodilator Agents*; Calcium Channels/metabolism*; Signal Transduction/drug effects*; Signal Transduction/physiology; Rats, Sprague-Dawley; Orthosiphon/chemistry*; In Vitro Techniques
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