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1.
Sci Rep ; 14(1): 16713, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39030264

ABSTRACT

Developing stable and highly efficient metal oxide photocatalysts remains a significant challenge in managing organic pollutants. In this study, zinc oxide nanoparticles (ZnO NPs) were successfully synthesized using various plant extracts, pomegranate (P.M), beetroot roots (B.S), and seder, along with a chemical process. The produced ZnO NPs were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), Field Emission Scanning Electron Microscope (FESEM), High-Resolution Transmission Electron Microscopy (HRTEM), and Surface Area. For all prepared samples, the results indicated that the composition of the plant extract affects several characteristics of the produced particles, such as their photocatalytic properties, energy bandgap (Eg), particle size, and the ratio of the two intensity (0 0 2) and (1 0 0) crystalline planes. The particle size of the produced NPs varies between 20 and 30 nm. To examine NPs' photocatalytic activity in the presence of UV light, Methyl Orange (MO) was utilized. The Eg of  ZnO synthesized by the chemical method was 3.16 e. V, whereas it was 2.84, 2.63, and 2.59 for P.M, Seder, and B.S extracts, respectively. The most effective ZnO NPs, synthesized using Beetroots, exhibited a degradation efficiency of 87 ± 0.5% with a kinetic rate constant of 0.007 min-1. The ratio of the two intensity (0 0 2) and (1 0 0) crystalline planes was also examined to determine a specific orientation in (0 0 2) that is linked to the production of oxygen vacancies in ZnO, which enhances their photocatalytic efficiency. Furthermore, the increase in photocatalytic effectiveness can be attributed to the improved light absorption by the inter-band gap states and effective charge transfer.

2.
Ann Med Surg (Lond) ; 79: 103887, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35860110

ABSTRACT

Inadvertent perioperative hypothermia is considered an emergency life-threatening situation. Clinical practice guidelines (CPGs) on how to manage hypothermia, based on evidence and expert opinions, could save lives. This systematic review assessed and compared the most recently approved international CPGs with the AGREE II instrument. We searched international bibliographic databases to identify relevant guidelines for managing perioperative hypothermia. Four independent reviewers (consultant anesthesiologists) critically appraised the selected guidelines with the AGREE II instrument. We analyzed inter-rater agreement and calculated an intra-class correlation coefficient (Kappa). We identified five CPGs for perioperative hypothermia that were eligible for critical appraisal. These CPGs were issued by the National Institute for Health and Care Excellence (NICE-2016); the American Society of Peri-Anesthesia Nurses/Agency for Health Care Research and Quality (ASPAN/AHRQ-2006); the University of Southern Mississippi (USM/CPG-2017); The University Assistance Complex of Salamanca (UACS/CPG-2018); and the Justus-Liebig University of Giessen (UKGM/CPG-2015). The overall assessments of NICE-2016 and ASPAN/AHRQ-2006 scored >80%. These results were consistent with high scores achieved in the six domains of AGREE II: (1) scope and purpose, (2) stakeholder involvement, (3) rigor of development, (4) clarity of presentation, (5) applicability, and (6) editorial independence domains. The NICE-2016, ASPAN/AHRQ-2006, and USM/CPG-2017) scored, respectively, 94%, 81%, and 70% for domain 3, 91%, 87%, and 66% for domain 5, and 90%, 82%, and 77% for domain 6. Generally, the NICE CPGs received significantly better clinical recommendations. However, all five evidence-based CPGs were of high methodological quality and were recommended for use in practice. Saudi Arabia should formulate its own national CPGs for diagnosis and management of perioperative hypothermia and to be published on NICE.

3.
J Dermatolog Treat ; 33(6): 2771-2781, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35737878

ABSTRACT

BACKGROUND: Psoriasis is considered one of the stubborn lifelong dermatologic diseases, making the patients seized in their social cage. Evidence-based clinical practice guidelines (CPGs) and expert opinions ensure that patients with psoriasis render the most recent and developed care. This systematic review assessed and compared the most recently approved international CPGs with the AGREE II instrument. METHODS: After we identified our research question, we searched the bibliographic international databases to identify and screen for relevant and eligible guidelines that address the topic of interest. Four independent reviewers (Senior Expert Dermatologist in Psoriasis) have critically appraised the selected guidelines via the AGREE II instrument. We conducted inter-rater analysis and percent agreement among raters and calculation of intra-class correlation coefficient (ICC) 'Kappa'. RESULTS: Out of 33 articles for CPGs, only Four eligible CPGs fulfill the inclusion criteria. Selected CPGs were critically appraised; first from the American College of Rheumatology that is also National Psoriasis Foundation (ACR/NPF-2018), second from the UK's National Institute for Health and Care Excellence (NICE-2017) for Psoriasis: Assessment and Management, third from the Saudi practical guidelines on the biologic treatment for Psoriasis (Saudi CPGs, 2015), and lastly from the American Academy of Dermatology (AAD/NPF-2019) Management and Treatment of Psoriasis with Awareness and Attention to Comorbidities. The complete assessments (OA) of two CPGs (AAD/NPF and NICE) scored greater than 80%; 'six domains' of AGREE II had greater score that is congruent with results; (1) scope and motive, (2) shareholder involvement, (3) rigor of growth, (4) clarity of speech, (5) validity, and (6) journalistic independence domains. Domain (3) scored (84, 71, and 90%), domain (5) (51%, 47, and 90%), domain (6) (70, 52, and 90%) for (Saudi CPGs, AAD/NPF, and NICE), respectively. Generally, the clinical recommendations were significantly better for NICE CPGs. CONCLUSIONS: Four evidence-based 'CPGs' introduced a high-quality methodological analysis. NICE indicated the greatest quality followed by Saudi CPGs and AAD/NPF and all four CPGs were suggested for practice.


Subject(s)
Psoriasis , Humans , Psoriasis/therapy
4.
Int J Biol Macromol ; 157: 187-201, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32344090

ABSTRACT

Three anionic chitosan surfactant with different hydrophobic tails labeled Chitosan-R8, Chitosan-R12 and Chitosan-R16 were prepared and their surface behavior in aqueous solution was determined by surface tension measurements at three different temperatures 20, 40 and 60 °C. The affinity of the synthesized anionic chitosan surfactant to form micelle enhanced with increasing the hydrophobic chain length as well as raising the solution temperature up to 60 °C. The anionic chitosan surfactant showed a great influence as capping agent for the in-situ preparation of silver nanoparticles (AgNPs) based on photochemical reduction method using sunlight as reducing agent. The chemical structure of chitosan surfactant showed a great effect on the size and stability of the prepared AgNPs. The Chitosan-R16 with longer hydrophobic tail, produce a uniform, small size & stable AgNPs compared to shorter tail Chitosan-R12 & Chitosan-R8. The prepared anionic chitosan showed good inhibiting effect against the steel corrosion in the 1.0 M HCl. The corrosion inhibition efficiency was determined using three different techniques, proving the ability of the new chitosan surfactant to inhibit the steel corrosion. The XPS results confirmed the formation of chitosan inhibitor on the steel surface.


Subject(s)
Chitosan/chemistry , Metal Nanoparticles/chemistry , Silver/chemistry , Steel/chemistry , Surface-Active Agents/chemistry , Anions , Corrosion , Micelles , Polymers/chemistry , Surface-Active Agents/chemical synthesis , Temperature
5.
Med J Malaysia ; 75(2): 169-170, 2020 03.
Article in English | MEDLINE | ID: mdl-32281601

ABSTRACT

Acute ischemic stroke (AIS) and acute ST-elevation myocardial infarction (STEMI) are leading causes of mortality worldwide. Concurrent AIS presentation with STEMI is rare and potentially fatal. Most importantly to date many centres in Malaysia are still not aware on how to treat this condition. We report a case of AIS, which was treated with intravenous tenecteplase (TNK) according to ischemic stroke dosage and lead to improvement of neurological deficit.


Subject(s)
Contraindications , Fibrinolytic Agents/administration & dosage , ST Elevation Myocardial Infarction/drug therapy , Stroke/drug therapy , Tenecteplase/administration & dosage , Administration, Intravenous , Adult , Humans , Malaysia , Male
6.
Int J Biol Macromol ; 152: 681-702, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32084486

ABSTRACT

Chitosan is the second abundant biopolymer present on earth after cellulose. Chitosan is extracted from the shells of shrimp and other crustaceans. Several methods were reported for its extraction, but the most commercial is the deacetylation of chitin. Chitosan as a biopolymer has numerous applications and uses. But, its mechanical, chemical and biological characteristics can be enhanced by modification of its chemical structures. Several modification methods and derivatives were reviewed in the literatures, and several were collected in this review. The reviewed modified chitosan derivatives herein were five types of derivatives. The first is substituted chitosan derivatives including thiolated, phosphorylated, and N-phthaloylated derivatives. The second is crosslinked chitosan derivatives including chitosan-glutaraldehyde, chitosan-ethylene diamine tetraacetic acid, and chitosan-epichlorohydrin derivatives. The third is carboxylic acid derivatives of chitosan obtained from carboxyalkylation, acrylation, methacrylation, and benzoylation of chitosan. The fourth is ionic chitosan derivatives including highly cationic and sulfated derivatives. The last is bounded chitosan to specific molecules including cyclodextrin, thiosemicarbazone, dioxime, and crown ether precursors. The review also highlights the reported advantages and applications of the modified chitosan and the synthetic routes of the biopolymer modification.


Subject(s)
Biopolymers/chemistry , Chitosan/chemistry , Animals , Cellulose/chemistry , Chitin/chemistry , Crustacea/chemistry
7.
Article in English | MEDLINE | ID: mdl-31531117

ABSTRACT

This study was aimed to investigate the structure of bioactive components of black seed oil (BSO) and their antimicrobial and cytotoxic effects. Initially, the structural examination was conducted using various spectroscopic techniques, such as FTIR, TLC, and UV-visible spectroscopy, which are important in determining substituents, functional groups, and the presence of conjugated double bonds in BSO. From the FTIR spectra, a variety of sharp, strong, and weak peaks were specified relating to the main components of thymoquinone (TQ), dithymoquinone, thymohydroquinone, and thymol in BSO. The results of UV-visible spectroscopy confirmed the presence of thymoquinone as a major compound, and conjugated double bonds were also found. In addition, qualitative TLC analysis was used to identify thymoquinone from the methanol-extracted layer in BSO, by calculating the retention factor (R f) value. Furthermore, antimicrobial activity of BSO was studied against various types of bacteria. Strong bacterial inhibitory effects were observed, especially against Bacillus subtilis, with an average inhibition zone of 15.74 mm. Moreover, through the use of the MTT assay in vitro, it was shown that BSO does not exhibit any cytotoxicity towards human peripheral blood mononuclear cells (PBMCs). It was also found from the structural characterization of BSO that the existence of TQ is responsible for potential antibacterial activity without any cytotoxic effects. The main observation of this work is that BSO has antimicrobial activity even against methicillin-resistant Staphylococcus aureus (MRSA).

8.
Int J Biol Macromol ; 83: 297-305, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26645144

ABSTRACT

Chitosan (Ch) grafted with poly(ethylene glycol) (Ch-g-mPEG) were synthesized using mPEG with molecular weights 2000 g/mol. The synthesized Ch-g-mPEG was characterized using gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), and X-ray diffraction (XRD) techniques. Ch-g-mPEG silver nanoparticles has been synthesized and characterized by high-resolution transmission electron microscopy (HRTEM) and energy dispersive analysis of X-rays (EDAX). The synthesized Ch-g-mPEG and its nanostructure were examined as corrosion inhibitors for carbon steel in 1M HCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results revealed that the inhibition efficiency obtained by Ch-g-mPEG self-assembled on silver nanoparticles is greater than that obtained by Ch-g-mPEG only. Potentiodynamic polarization results reveal that the synthesized compound could be classified as mixed-type corrosion inhibitors with predominant control of the cathodic reaction. The results of EIS indicate that the both charge transfer resistance and inhibition efficiency tend to increase by increasing the inhibitor concentration.


Subject(s)
Chitosan/chemistry , Metal Nanoparticles/chemistry , Polyethylene Glycols/chemistry , Silver/chemistry , Chemistry Techniques, Synthetic , Corrosion , Hydrochloric Acid/chemistry , Polyethylene Glycols/chemical synthesis , Steel/chemistry
9.
Int J Biol Macromol ; 81: 400-9, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26282929

ABSTRACT

Biosorption of Cu(II), Co(II) and Fe(III) ions from aqueous solutions by rice husk, palm leaf and water hyacinth was investigated as a function of initial pH, initial heavy metal ions concentration and treatment time. The adsorption process was examined by two adsorption isotherms: Langmuir and Freundlich isotherms. The experimental data of biosorption process were analyzed using pseudo-first order, pseudo-second order kinetic models. The equilibrium biosorption isotherms showed that the three studied biosorbents possess high affinity and sorption capacity for Cu(II), Co(II) and Fe(III) ions. Rice husk showed more efficiency than palm leaf and water hyacinth. Adsorption of Cu(II) and Co(II) was more efficient in alkaline medium (pH 9) than neutral medium due to the high solubility of metal ion complexes. The metal removal efficiency of each biosorbent was correlated to its chemical structure. DTA studies showed formation of metal complex between the biosorbents and the metal ions. The obtained results showed that the tested biosorbents are efficient and alternate low-cost biosorbent for removal of heavy metal ions from aqueous media.


Subject(s)
Metals, Heavy/chemistry , Adsorption , Agriculture , Cellulose/chemistry , Hydrogen-Ion Concentration , Ions/chemistry , Kinetics , Lignin/chemistry , Molecular Structure , Temperature , Wastewater/chemistry , Water Purification/methods
10.
Clin Genet ; 87(1): 56-61, 2015.
Article in English | MEDLINE | ID: mdl-24354460

ABSTRACT

An extremely rare pellagra-like condition has been described, which was partially responsive to niacin and associated with a multisystem involvement. The condition was proposed to represent a novel autosomal recessive entity but the underlying mutation remained unknown for almost three decades. The objective of this study was to identify the causal mutation in the pellagra-like condition and investigate the mechanism by which niacin confers clinical benefit. Autozygosity mapping and exome sequencing were used to identify the causal mutation, and comet assay on patient fibroblasts before and after niacin treatment to assess its effect on DNA damage. We identified a single disease locus that harbors a novel mutation in ERCC5, thus confirming that the condition is in fact xeroderma pigmentosum/Cockayne syndrome (XP/CS) complex. Importantly, we also show that the previously described dermatological response to niacin is consistent with a dramatic protective effect against ultraviolet-induced DNA damage in patient fibroblasts conferred by niacin treatment. Our findings show the power of exome sequencing in reassigning previously described novel clinical entities, and suggest a mechanism for the dermatological response to niacin in patients with XP/CS complex. This raises interesting possibilities about the potential therapeutic use of niacin in XP.


Subject(s)
Cockayne Syndrome/drug therapy , Cockayne Syndrome/pathology , DNA-Binding Proteins/genetics , Endonucleases/genetics , Niacin/therapeutic use , Nuclear Proteins/genetics , Pellagra/pathology , Transcription Factors/genetics , Xeroderma Pigmentosum/drug therapy , Xeroderma Pigmentosum/pathology , Base Sequence , Child, Preschool , Cockayne Syndrome/genetics , Comet Assay , DNA Damage/drug effects , DNA Damage/radiation effects , Exome/genetics , Fatal Outcome , Female , Humans , Infant , Molecular Sequence Data , Niacin/pharmacology , Pedigree , Sequence Analysis, DNA , Xeroderma Pigmentosum/genetics
11.
Clin Genet ; 85(4): 371-5, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23574405

ABSTRACT

Nephronophthisis is the most common genetic cause of renal failure in children and young adults. It is genetically heterogeneous and can be seen in isolation or in combination with other ciliopathy phenotypes. Here we report an index case where nephronophthisis is associated with oculomotor apraxia and cerebellar abnormalities, consistent with the clinical diagnosis of cerebello-oculo-renal syndrome. Prompted by a family history of an uncle with early onset end stage renal failure and infertility, we performed semen analysis on the index. This revealed marked reduction in the count of motile sperms as well as multiple abnormalities in the head and tail. Autozygome-guided mutation analysis followed by exome sequencing and segregation analysis revealed a homozygous truncating mutation in NPHP4, indicating that mutations of this gene can on rare occasions cause cerebello-oculo-renal syndrome. Our finding of severe male infertility in a family with NPHP4 truncation is strongly supported by the mouse model and, to our knowledge, is the first reported male infertility phenotype in association with NPHP4 or any other nephrocystin in humans.


Subject(s)
Cerebellar Diseases/genetics , Cogan Syndrome/genetics , Infertility, Male/genetics , Kidney Diseases, Cystic/genetics , Mutation , Proteins/genetics , Adolescent , Apraxias/congenital , Homozygote , Humans , Male , Pedigree , Syndrome
12.
Clin Ter ; 164(5): 391-5, 2013.
Article in English | MEDLINE | ID: mdl-24217823

ABSTRACT

BACKGROUND AND AIMS: Coronary heart disease is a major health problem in Malaysia with high morbidity and mortality. Common primary screening tool of cardiovascular risk stratification is exercise treadmill test (ETT). This communication is to determine the performance of coronary artery calcium score a new method to stratify the presence of obstructive coronary artery disease (CAD) in comparison to traditional ETT in patients having coronary artery diseases. MATERIALS AND METHODS: Patients between 30 to 60 years old attended the ETT to screen for ischemic heart disease were recruited for Agatston coronary artery calcium score (CACS) of multi-sliced computed tomography (MSCT). Subsequently all patients underwent a full MSCT coronary angiography. The major determinant was the state of CAD whether obstructive (50% stenosis or more) or non-obstructive (less than 50% stenosis). All patients diagnosed with obstructive CAD on MSCT coronary angiogram were subjected to invasive coronary angiogram (ICA) to confirm the findings and planned the need for revascularization. RESULTS: The CACS was 100% sensitivity and 97.5% specificity in detecting obstructive CAD at the optimal cut-off value of 106.5 and above. The positive predictive value (PPV) at CACS ≥ 106 was 71.4% and the negative predictive value (NPV) was consistent at 100%. Compare to ETT, the CACS discriminative value and diagnostic performance was much better (PPV 71.4% vs. 45.5%), respectively. CONCLUSION: CACS can be a good diagnostic screening tool in patients suspected of CAD, and particularly within the non-diagnostic ETT subgroup with low to moderate cardiovascular risks.


Subject(s)
Calcinosis/epidemiology , Coronary Artery Disease/epidemiology , Multidetector Computed Tomography , Adult , Calcinosis/diagnostic imaging , Comorbidity , Coronary Angiography , Coronary Artery Disease/diagnosis , Coronary Artery Disease/diagnostic imaging , Cross-Sectional Studies , Diabetes Mellitus/epidemiology , Exercise Test , Female , Humans , Hyperlipidemias/epidemiology , Hypertension/epidemiology , Malaysia/epidemiology , Male , Middle Aged , Predictive Value of Tests , Risk Assessment , Risk Factors , Sensitivity and Specificity , Severity of Illness Index , Smoking/epidemiology
13.
J Surfactants Deterg ; 16(2): 233-242, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23420292

ABSTRACT

Chitosan is one of the important biopolymers and it is extracted from exoskeletons of crustaceans in sea food waste. It is a suitable eco-friendly carbon steel corrosion inhibitor in acid media; the deacetylation degree of prepared chitosan is more than 85.16 %, and the molecular weight average is 109 kDa. Chitosan was modified to 2-N,N-diethylbenzene ammonium chloride N-oxoethyl chitosan (compound I), and 12-ammonium chloride N-oxododecan chitosan (compound II) as soluble water derivatives. The corrosion inhibition efficiency for carbon steel of compound (I) in 1 M HCl at varying temperature is higher than for chitosan and compound (II). However, the antibacterial activity of chitosan for Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, and Candida albicans is higher than for its derivatives, and the minimum inhibition concentration and minimum bacterial concentration of chitosan and its derivatives were carried out with the same strain.

14.
Article in English | MEDLINE | ID: mdl-16771229

ABSTRACT

Rhodococcus equi, a recognized pathogen in horses, is emerging as a human opportunistic pathogen, especially in immunocompromized hosts. We describe four immunocompromized patients who had serious R. equi infections with an overall mortality of 75%. The natural habitat of R. equi is soil, particularly soil contaminated with animal manure. Necrotizing pneumonia is the commonest form of infection but extrapulmonary infections, such as wound infections and subcutaneous abscess, have also been described in humans. R. equi is cultured easily in ordinary non-selective media. Large, smooth, irregular colonies appear within 48 hours. It is a facultative, intracellular, nonmotile, non-spore forming, gram-positive coccobacillus, which is weakly acid-fast staining and bears a similarity to diphtheroids. It forms a salmon-colored pigment usually after 48 hours incubation. A particular characteristic of this organism is that it undergoes synergistic hemolysis with some bacteria on sheep blood agar. R. equi may be misidentified as diphtheroids, Mycobacterium species, or Nocardia. In vitro R. equi is usually susceptible to erythromycin, ciprofloxacin, vancomycin, aminoglycosides, rifampin, imipenem and meropenem. The organism can be difficult to eradicate, making treatment challenging. Increased awareness of the infection may help with early diagnosis and timely treatment.


Subject(s)
Actinomycetales Infections/diagnosis , Immunocompromised Host , Opportunistic Infections/diagnosis , Rhodococcus equi , Actinomycetales Infections/drug therapy , Actinomycetales Infections/microbiology , Adolescent , Adult , Anti-Bacterial Agents/therapeutic use , Fatal Outcome , Female , Humans , Malaysia , Male , Middle Aged , Opportunistic Infections/drug therapy , Opportunistic Infections/microbiology
15.
Nucleosides Nucleotides Nucleic Acids ; 20(9): 1683-90, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11580194

ABSTRACT

Treatment of D-arabino-hexose phenylosotriazole with conc. hydrochloric acid afforded a new type of alpha- and beta-glycosides of D-erythrose formed by reaction of the 3,6-anhydro derivative with the in situ formed 2-phenyl-4-(formylmethyl)- 1,2,3-triazole.


Subject(s)
Glycosides/chemistry , Polysaccharides/chemistry , Triazoles/chemistry , Triazoles/chemical synthesis , Cephalosporins/chemical synthesis , Cephalosporins/chemistry , Hydrochloric Acid/chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Models, Chemical
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