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The regulation of Cytochrome f by mannose treatment in broccoli and its relationship with programmed cell death in tobacco BY-2 cells

Zhao S, Chen J, Cao S, Wang H, Chen H, Wei Y, et al.

Plant Physiol Biochem, 2024 Mar;208:108480.
PMID: 38437751 DOI: 10.1016/j.plaphy.2024.108480

It is well established that programmed cell death (PCD) occurred in broccoli during postharvest senescence, but no studies have been conducted on the regulation of broccoli cytochrome f by mannose treatment and its relationship with PCD. In this study, we treated broccoli buds with mannose to investigate the changes in color, total chlorophyll content, gene expression related to chlorophyll metabolism, chloroplast structure, and cytochrome f determination during postharvest storage. In addition, to investigate the effect of cytochrome f on PCD, we extracted cytochrome f from broccoli and treated Nicotiana tabacum L. cv Bright Yellow 2 (BY-2) cells with extracted cytochrome f from broccoli at various concentrations. The results showed that cytochrome f can induce PCD in tobacco BY-2 cells, as evidenced by altered cell morphology, nuclear chromatin disintegration, DNA degradation, decreased cell viability, and increased caspase-3-like protease production. Taken together, our study indicated that mannose could effectively delay senescence of postharvest broccoli by inhibiting the expression of gene encoding cytochrome f which could induce PCD.

Matched MeSH terms: Mannose/metabolism; Mannose/pharmacology
Biotechnological enhancement of lactic acid conversion from pretreated palm kernel cake hydrolysate by Actinobacillus succinogenes 130Z

Rahim NA, Luthfi AAI, Bukhari NA, Tan JP, Abdul PM, Manaf SFA

Sci Rep, 2023 Apr 08;13(1):5787.
PMID: 37031272 DOI: 10.1038/s41598-023-32964-z

The aim of this study was to establish an improved pretreatment and fermentation method i.e. immobilized cells for high recovery of fermentable sugars from palm kernel cake (PKC) and its effects on fermentability performance by Actinobacillus succinogenes 130Z in the conversion of the fermentable sugar to lactic acid. The effects of oxalic acid concentrations (1-6% w/v) and residence times (1-5 h) on the sugar recovery were initially investigated and it was found that the highest mannose concentration was 25.1 g/L at the optimum hydrolysis conditions of 4 h and 3% (w/v) oxalic acid. The subsequent enzymatic saccharification of the pretreated PKC afforded the highest enzymatic digestibility with the recovered sugars amounting to 25.18 g/L and 9.14 g/L of mannose and glucose, respectively. Subsequently, the fermentability performance of PKC hydrolysate was evaluated and compared in terms of cultivation phases (i.e. mono and dual-phases), carbonate loadings (i.e. magnesium and sodium carbonates), and types of sugars (i.e. glucose and mannose). The highest titer of 19.4 g/L lactic acid was obtained from the fermentation involving A. succinogenes 130Z in dual-phase cultivation supplemented with 30 g/L of magnesium carbonate. Lactic acid production was further enhanced by using immobilized cells with coconut shell-activated carbon (CSAC) of different sizes (A, B, C, and D) in the repeated batch cultivation of dual-phase fermentation producing 31.64 g/L of lactic acid. This work sheds light on the possibilities to enhance the utilization of PKC for lactic acid production via immobilized A. succinogenes 130Z.

Matched MeSH terms: Mannose*
Structural characterization and evaluation of prebiotic activity of oil palm kernel cake mannanoligosaccharides

Kalidas NR, Saminathan M, Ismail IS, Abas F, Maity P, Islam SS, et al.

Food Chem, 2017 Nov 01;234:348-355.
PMID: 28551246 DOI: 10.1016/j.foodchem.2017.04.159

In this study, mannanoligosaccharides (MOS) were isolated from palm kernel cake by aqueous extraction using high temperature and pressure. Structural characterization of MOS was carried out using acid hydrolysis, methylation analysis, ESI-MS/MS and 1D/2D NMR. The prebiotic activity of MOS was evaluated in vitro using two probiotic Lactobacillus strains. Sugar analysis indicated the presence of mannose in each of the oligomers. Methylation and 1D/2D NMR analysis indicated that the MOS have a linear structure consisting of (1→4)-β-d-mannopyranosyl residues. ESI-MS/MS results showed that the isolated mannan oligomers, MOS-III, MOS-IV, MOS-V and MOS-VI consist of tetra-, penta-, hexa-, and hepta-saccharides with molecular weights of 689, 851, 1013 and 1151Da, respectively. Based on the in vitro growth study, MOS-III and MOS-IV was found to be effective in selectively promoting the growth of Lactobacillus reuteri C1 strain as evidenced by the optical density of the culture broth.

Matched MeSH terms: Mannose/chemistry*
Biolistic-mediated production of transgenic oil palm

Parveez GK, Bahariah B

Methods Mol Biol, 2012;847:163-75.
PMID: 22351007 DOI: 10.1007/978-1-61779-558-9_14

The effectiveness of mannose (using phosphomannose isomerase [pmi] gene) as a positive selection agent to preferably allow the growth of transformed oil palm embryogenic calli was successfully evaluated. Using the above selection agent in combination with the previously optimized physical and biological parameters and the best constitutive promoter, oil palm embryogenic calli were transformed with pmi gene for producing transgenic plants. Bombarded embryogenic calli were exposed to embryogenic calli medium containing 30:0 g/L mannose to sucrose 3 weeks postbombardment. Selectively, proliferating embryogenic calli started to emerge around 6 months on the above selection medium. The proliferated embryogenic calli were individually isolated once they reached a specific size and regenerated to produce complete plantlets. The complete regenerated plantlets were evaluated for the presence of transgenes by PCR and Southern analyses.

Matched MeSH terms: Mannose/metabolism; Mannose-6-Phosphate Isomerase/genetics*
Fulltext Complement system specifically C5a receptor, inflammation and hypertrophic cardiomyopathy (HCM) in cats

Khor, K.H.

Jurnal Veterinar Malaysia, 2015;27(2):12-15.
MyJurnal

The complement cascade is a unique sequence of molecular events occurring within the vascular system in which inactive plasma proteins synthesised by the liver are activated following tissue injury (Figure ) (McGavin and Zachary, 2007). The increase permeability of blood vessels during inflammation is stimulated, at least in part, by the complement system. The complement system is a complex system of 30 serum proteins. Many early components are serine proteases that are activated sequentially to form a cascade. The complement cascade is activated through any one, or more, of four pathways: the classical, the mannan-binding lectin (MBL), the alternative and the extrinsic protease pathways (Guo and Ward, 2005; Monk et al., 2007; Ricklin and Lambris, 2007). For further information, refer (Manthey et al., 2009). (Copied from article)

Matched MeSH terms: Mannose-Binding Lectin
Atomistic simulation studies of the α/β-glucoside and galactoside in anhydrous bilayers: effect of the anomeric and epimeric configurations

Ahmadi S, Manickam Achari V, Nguan H, Hashim R

J Mol Model, 2014 Mar;20(3):2165.
PMID: 24623320 DOI: 10.1007/s00894-014-2165-0

Fully atomistic molecular dynamics simulation studies of thermotropic bilayers were performed using a set of glycosides namely n-octyl-β-D-glucopyranoside (β-C8Glc), n-octyl-α-D-glucopyranoside (α-C8Glc), n-octyl-β-D-galactopyranoside (β-C8Gal), and n-octyl-α-D-galactopyranoside (α-C8Gal) to investigate the stereochemical relationship of the epimeric/anomeric quartet liner glycolipids with the same octyl chain group. The results showed that, the anomeric stereochemistry or the axial/equatorial orientation of C1-O1 (α/β) is an important factor controlling the area and d-spacing of glycolipid bilayer systems in the thermotropic phase. The head group tilt angle and the chain ordering properties are affected by the anomeric effect. In addition, the L(C) phase of β-C8Gal, is tilting less compared to those in the fluid L(α). The stereochemistry of the C4-epimeric (axial/equatorial) and anomeric (α/β) centers simultaneously influence the inter-molecular hydrogen bond. Thus, the trend in the values of the hydrogen bond for these glycosides is β-C8Gal > α-C8Glc > β-C8Glc > α-C8Gal. The four bilayer systems showed anomalous diffusion behavior with an observed trend for the diffusion coefficients; and this trend is β-C8Gal > β-C8Glc > α-C8Gal > α-C8Glc. The "bent" configuration of the α-anomer results in an increase of the hydrophobic area, chain vibration and chain disorganization. Since thermal energy is dispensed more entropically for the chain region, the overall molecular diffusion decreases.

Matched MeSH terms: Mannose/chemistry
Enhanced mannan-derived fermentable sugars of palm kernel cake by mannanase-catalyzed hydrolysis for production of biobutanol

Shukor H, Abdeshahian P, Al-Shorgani NK, Hamid AA, Rahman NA, Kalil MS

Bioresour Technol, 2016 Oct;218:257-64.
PMID: 27372004 DOI: 10.1016/j.biortech.2016.06.084

Catalytic depolymerization of mannan composition of palm kernel cake (PKC) by mannanase was optimized to enhance the release of mannan-derived monomeric sugars for further application in acetone-butanol-ethanol (ABE) fermentation. Efficiency of enzymatic hydrolysis of PKC was studied by evaluating effects of PKC concentration, mannanase loading, hydrolysis pH value, reaction temperature and hydrolysis time on production of fermentable sugars using one-way analysis of variance (ANOVA). The ANOVA results revealed that all factors studied had highly significant effects on total sugar liberated (P<0.01). The optimum conditions for PKC hydrolysis were 20% (w/v) PKC concentration, 5% (w/w) mannanase loading, hydrolysis pH 4.5, 45°C temperature and 72h hydrolysis time. Enzymatic experiments in optimum conditions revealed total fermentable sugars of 71.54±2.54g/L were produced including 67.47±2.51g/L mannose and 2.94±0.03g/L glucose. ABE fermentation of sugar hydrolysate by Clostridium saccharoperbutylacetonicum N1-4 resulted in 3.27±1.003g/L biobutanol.

Matched MeSH terms: Mannose/chemistry
Fulltext Structural Basis of Specific Glucoimidazole and Mannoimidazole Binding by Os3BGlu7

Nutho B, Pengthaisong S, Tankrathok A, Lee VS, Ketudat Cairns JR, Rungrotmongkol T, et al.

Biomolecules, 2020 Jun 15;10(6).
PMID: 32549280 DOI: 10.3390/biom10060907

β-Glucosidases and β-mannosidases hydrolyze substrates that differ only in the epimer of the nonreducing terminal sugar moiety, but most such enzymes show a strong preference for one activity or the other. Rice Os3BGlu7 and Os7BGlu26 β-glycosidases show a less strong preference, but Os3BGlu7 and Os7BGlu26 prefer glucosides and mannosides, respectively. Previous studies of crystal structures with glucoimidazole (GIm) and mannoimidazole (MIm) complexes and metadynamic simulations suggested that Os7BGlu26 hydrolyzes mannosides via the B2,5 transition state (TS) conformation preferred for mannosides and glucosides via their preferred 4H3/4E TS conformation. However, MIm is weakly bound by both enzymes. In the present study, we found that MIm was not bound in the active site of crystallized Os3BGlu7, but GIm was tightly bound in the -1 subsite in a 4H3/4E conformation via hydrogen bonds with the surrounding residues. One-microsecond molecular dynamics simulations showed that GIm was stably bound in the Os3BGlu7 active site and the glycone-binding site with little distortion. In contrast, MIm initialized in the B2,5 conformation rapidly relaxed to a E3/4H3 conformation and moved out into a position in the entrance of the active site, where it bound more stably despite making fewer interactions. The lack of MIm binding in the glycone site in protein crystals and simulations implies that the energy required to distort MIm to the B2,5 conformation for optimal active site residue interactions is sufficient to offset the energy of those interactions in Os3BGlu7. This balance between distortion and binding energy may also provide a rationale for glucosidase versus mannosidase specificity in plant β-glycosidases.

Matched MeSH terms: Mannose/chemistry
Fulltext Structures and binding specificity of galactose- and mannose-binding lectins from champedak: differences from jackfruit lectins

Gabrielsen M, Abdul-Rahman PS, Othman S, Hashim OH, Cogdell RJ

Acta Crystallogr F Struct Biol Commun, 2014 Jun;70(Pt 6):709-16.
PMID: 24915077 DOI: 10.1107/S2053230X14008966

Galactose-binding and mannose-binding lectins from the champedak fruit, which is native to South-east Asia, exhibit useful potential clinical applications. The specificity of the two lectins for their respective ligands allows the detection of potential cancer biomarkers and monitoring of the glycosylated state of proteins in human serum and/or urine. To fully understand and expand the use of these natural proteins, their complete sequences and crystal structures are presented here, together with details of sugar binding.

Matched MeSH terms: Mannose/chemistry*
The mRNA expression of soluble urokinase plasminogen activator surface receptor in human adipose tissue is positively correlated with body mass index

Ng HF, Chin KF, Chan KG, Ngeow YF

Genome, 2015 Jun;58(6):315-21.
PMID: 26284904 DOI: 10.1139/gen-2015-0028

suPLAUR is the transcript variant that encodes the soluble form of the urokinase plasminogen activator surface receptor (suPLAUR). This soluble protein has been shown to enhance leukocyte migration and adhesion, and its circulatory level is increased in inflammatory states. In this pilot study, we used RNA-Seq to examine the splicing pattern of PLAUR in omental adipose tissues from obese and lean individuals. Of the three transcript variants of the PLAUR gene, only the proportion of suPLAUR (transcript variant 2) increases in obesity. After removing the effects of gender and age, the expression of suPLAUR is positively correlated with body mass index. This observation was validated using RT-qPCR with an independent cohort of samples. Additionally, in our RNA-Seq differential expression analysis, we also observed, in obese adipose tissues, an up-regulation of genes encoding other proteins involved in the process of chemotaxis and leukocyte adhesion; of particular interest is the integrin beta 2 (ITGB2) that is known to interact with suPLAUR in leukocyte adhesion. These findings suggest an important role for suPLAUR in the recruitment of immune cells to obese adipose tissue, in the pathogenesis of obesity.

Matched MeSH terms: Mannose-Binding Lectins/genetics*; Mannose-Binding Lectins/metabolism
Macrobrachium rosenbergii mannose binding lectin: synthesis of MrMBL-N20 and MrMBL-C16 peptides and their antimicrobial characterization, bioinformatics and relative gene expression analysis

Arockiaraj J, Chaurasia MK, Kumaresan V, Palanisamy R, Harikrishnan R, Pasupuleti M, et al.

Fish Shellfish Immunol, 2015 Apr;43(2):364-74.
PMID: 25575476 DOI: 10.1016/j.fsi.2014.12.036

Mannose-binding lectin (MBL), an antimicrobial protein, is an important component of innate immune system which recognizes repetitive sugar groups on the surface of bacteria and viruses leading to activation of the complement system. In this study, we reported a complete molecular characterization of cDNA encoded for MBL from freshwater prawn Macrobrachium rosenbergii (Mr). Two short peptides (MrMBL-N20: (20)AWNTYDYMKREHSLVKPYQG(39) and MrMBL-C16: (307)GGLFYVKHKEQQRKRF(322)) were synthesized from the MrMBL polypeptide. The purity of the MrMBL-N20 (89%) and MrMBL-C16 (93%) peptides were confirmed by MS analysis (MALDI-ToF). The purified peptides were used for further antimicrobial characterization including minimum inhibitory concentration (MIC) assay, kinetics of bactericidal efficiency and analysis of hemolytic capacity. The peptides exhibited antimicrobial activity towards all the Gram-negative bacteria taken for analysis, whereas they showed the activity towards only a few selected Gram-positive bacteria. MrMBL-C16 peptides produced the highest inhibition towards both the Gram-negative and Gram-positive bacteria compared to the MrMBL-N20. Both peptides do not produce any inhibition against Bacillus sps. The kinetics of bactericidal efficiency showed that the peptides drastically reduced the number of surviving bacterial colonies after 24 h incubation. The results of hemolytic activity showed that both peptides produced strong activity at higher concentration. However, MrMBL-C16 peptide produced the highest activity compared to the MrMBL-N20 peptide. Overall, the results indicated that the peptides can be used as bactericidal agents. The MrMBL protein sequence was characterized using various bioinformatics tools including phylogenetic analysis and structure prediction. We also reported the MrMBL gene expression pattern upon viral and bacterial infection in M. rosenbergii gills. It could be concluded that the prawn MBL may be one of the important molecule which is involved in antimicrobial mechanism. Moreover, MrMBL derived MrMBL-N20 and MrMBL-C16 peptides are important antimicrobial peptides for the recognition and eradication of viral and bacterial pathogens.

Matched MeSH terms: Mannose-Binding Lectins/genetics*; Mannose-Binding Lectins/metabolism; Mannose-Binding Lectins/chemistry
Monashia flava gen. nov., sp. nov., an actinobacterium of the family Intrasporangiaceae

Azman AS, Zainal N, Mutalib NA, Yin WF, Chan KG, Lee LH

Int J Syst Evol Microbiol, 2016 Feb;66(2):554-561.
PMID: 26556816 DOI: 10.1099/ijsem.0.000753

A novel actinobacterial strain, MUSC 78T, was isolated from a mangrove soil collected from Peninsular Malaysia. The taxonomic status of this strain was determined using a polyphasic approach. Comparative 16S rRNA gene sequence analysis revealed that strain MUSC 78T represented a novel lineage within the class Actinobacteria. Strain MUSC 78T formed a distinct clade in the family Intrasporangiaceae and was related most closely to members of the genera Terrabacter (98.3-96.8 % 16S rRNA gene sequence similarity), Intrasporangium (98.2-96.8 %), Humibacillus (97.2 %), Janibacter (97.0-95.3 %), Terracoccus (96.8 %), Kribbia (96.6 %), Phycicoccus (96.2-94.7 %), Knoellia (96.1-94.8 %), Tetrasphaera (96.0-94.9 %) and Lapillicoccus (95.9 %). Cells were irregular rod-shaped or cocci and stained Gram-positive. The cell-wall peptidoglycan type was A3γ, with ll-diaminopimelic acid as the diagnostic diamino acid. The main cell-wall sugar was mannose and lower amounts of galactose and rhamnose were present. The predominant menaquinone was MK-8(H4). The polar lipid profile consisted of phosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, diphosphatidylglycerol and phosphoglycolipid. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C16 : 0. The DNA G+C content was 73.1 mol%. Based on this polyphasic study, MUSC 78T exhibited phylogenetic and phenotypic differences from members of the genera of the family Intrasporangiaceae, and therefore a novel species of a new genus, Monashia flava gen. nov., sp. nov., is proposed. The type strain of Monashia flava is MUSC 78T ( = DSM 29621T = MCCC 1K00454T = NBRC 110749T).

Matched MeSH terms: Mannose
Molecular structure, chemical properties and biological activities of Pinto bean pod polysaccharide

Kamarudin F, Gan CY

Int J Biol Macromol, 2016 Jul;88:280-7.
PMID: 27044345 DOI: 10.1016/j.ijbiomac.2016.04.003

Pinto bean pod polysaccharide (PBPP) was successfully extracted with yield of 38.5g/100g and the PBPP gave total carbohydrate and uronic acid contents of 286.2mg maltose equivalent/g and 374.3mgGal/g, respectively. The Mw of PBPP was 270.6kDa with intrinsic viscosity of 0.262dm(3)/g, which composed of mannose (2.5%), galacturonic acid (15.0%), rhamnose (4.0%), glucose (9.0%), galactose (62.2%), xylose (2.9%) and arabinose (4.3%) with trace amount of ribose and fucose. The result suggested that PBPP has a spherical conformation with a highly branched structure. Fourier Transform Infrared analysis showed that PBPP has a similar structure as commercial pectin with an esterification degree of 59.9%, whereas scanning electron microscopy study showed that the crude polysaccharide formed a thin layer of film that was made of multiple micro strands of fibre. PBPP exhibited substantial free radical scavenging activity (7.7%), metal reducing capability (2.04mmol/dm(3)) and α-amylase inhibitory activity (97.6%) at a total amount of 1mg. PBPP also exhibited high water- and oil-holding capacities (3.6g/g and 2.8g/g, respectively). At a low concentration, PBPP exhibited emulsifying activity of 39.6% with stability of 38.6%. Apart from that, PBPP was able to show thickening capability at low concentration (0.005kg/dm(3)).

Matched MeSH terms: Mannose
Fulltext Evaluation of the effect of soluble polysaccharides of palm kernel cake as a potential prebiotic on the growth of probiotics

Bello B, Mustafa S, Tan JS, Ibrahim TAT, Tam YJ, Ariff AB, et al.

3 Biotech, 2018 Aug;8(8):346.
PMID: 30073131 DOI: 10.1007/s13205-018-1362-4

This paper deliberates the extraction, characterization and examination of potential application of soluble polysaccharides of palm kernel cake (PKC) as a prebiotic. The PKC was defatted and crude polysaccharide was obtained through water, citric acid or NaOH extraction. The physiochemical properties of the extracted polysaccharides viz. total carbohydrates, protein content, solubility rate, monosaccharides composition, structural information and thermal properties were also determined. The extracted soluble polysaccharides were further subjected to a digestibility test using artificial human gastric juice. Finally, their prebiotic potential on two probiotics, namely Lactobacillus plantarum ATCC 8014 and Lb. rhamnosus ATCC 53103 were evaluated in vitro. It was observed that PKC contained ash (5.2%), moisture (7.4%), carbohydrates (65.8%), protein (16.5%) and fat (5.1%). There were significant differences (P 95%). Protein content in SCPW, SCPCA and SCPN are 0.72, 0.40 and 0.58, respectively, and the peaks which indicated the presence of protein were observed at approximately 1640 cm-1 (amide I). FTIR spectroscopy revealed that the polysaccharides extracts were linked to β and α-glycosidic bonds and thermal analysis using differential scanning calorimeter (DSC) showed the main degradation temperature of SP is about 121 to 125 °C. The SP were found to be highly resistance (> 96%) to hydrolysis when subjected to artificial human gastric juice. The prebiotics potentials of the polysaccharides on probiotics in vitro demonstrated an increase in proliferation of Lb. plantarum ATCC 8014 and Lb. rhamnosus ATCC 53103 with decrease in the pH of the medium and producing organic acids.All the above findings strongly indicated that polysaccharides extracted from PKC, an industrial waste, have a potential to be exploited as novel prebiotics.

Matched MeSH terms: Mannose
Fulltext 1H-NMR-Based Metabolomics: An Integrated Approach for the Detection of the Adulteration in Chicken, Chevon, Beef and Donkey Meat

Akhtar MT, Samar M, Shami AA, Mumtaz MW, Mukhtar H, Tahir A, et al.

Molecules, 2021 Jul 30;26(15).
PMID: 34361796 DOI: 10.3390/molecules26154643

Meat is a rich source of energy that provides high-value animal protein, fats, vitamins, minerals and trace amounts of carbohydrates. Globally, different types of meats are consumed to fulfill nutritional requirements. However, the increasing burden on the livestock industry has triggered the mixing of high-price meat species with low-quality/-price meat. This work aimed to differentiate different meat samples on the basis of metabolites. The metabolic difference between various meat samples was investigated through Nuclear Magnetic Resonance spectroscopy coupled with multivariate data analysis approaches like principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). In total, 37 metabolites were identified in the gluteal muscle tissues of cow, goat, donkey and chicken using 1H-NMR spectroscopy. PCA was found unable to completely differentiate between meat types, whereas OPLS-DA showed an apparent separation and successfully differentiated samples from all four types of meat. Lactate, creatine, choline, acetate, leucine, isoleucine, valine, formate, carnitine, glutamate, 3-hydroxybutyrate and α-mannose were found as the major discriminating metabolites between white (chicken) and red meat (chevon, beef and donkey). However, inosine, lactate, uracil, carnosine, format, pyruvate, carnitine, creatine and acetate were found responsible for differentiating chevon, beef and donkey meat. The relative quantification of differentiating metabolites was performed using one-way ANOVA and Tukey test. Our results showed that NMR-based metabolomics is a powerful tool for the identification of novel signatures (potential biomarkers) to characterize meats from different sources and could potentially be used for quality control purposes in order to differentiate different meat types.

Matched MeSH terms: Mannose/analysis
Production of a monoclonal antibody against a mannose-binding protein of Acanthamoeba culbertsoni and its localization

Kang AY, Park AY, Shin HJ, Khan NA, Maciver SK, Jung SY

Exp Parasitol, 2018 Sep;192:19-24.
PMID: 30031120 DOI: 10.1016/j.exppara.2018.07.009

Amoebae from the genus Acanthamoeba are facultative pathogens of humans and other animals. In humans they most frequently infect the eye causing a sight threatening infection known as Acanthamoeba keratitis (AK), and also cause an often fatal encephalitis (GAE). A mannose-binding protein (MBP) has been identified as being important for Acanthamoeba infection especially in AK. This lectin has previously been characterized from Acanthamoeba castellanii as consisting of multiple 130 kDa subunits. MBP expression correlates with pathogenic potential and is expressed in a number of Acanthamoeba species. Here we report the purification of a similar lectin from Acanthamoeba culbertsoni and the production of a monoclonal antibody to it. The A. culbertsoni MBP was isolated by affinity chromatography using α-D-mannose agarose and has an apparent molecular weight of 83 kDa. The monoclonal antibody is an IgM that is useful in both western blots and immunofluorescence. We expect that this antibody will be useful in the study of the pathology of A. culbertsoni and in its identification in clinical samples.

Matched MeSH terms: Mannose-Binding Lectin/immunology*
Augmented delivery of gemcitabine in lung cancer cells exploring mannose anchored solid lipid nanoparticles

Soni N, Soni N, Pandey H, Maheshwari R, Kesharwani P, Tekade RK

J Colloid Interface Sci, 2016 Nov 01;481:107-16.
PMID: 27459173 DOI: 10.1016/j.jcis.2016.07.020

Gemcitabine (GmcH) is an effective anti-cancer agent used in the chemotherapy of lung cancer. However, the clinical applications of GmcH has been impeded primarily due to its low blood residence time, unfavorable pharmacokinetic and pharmacodynamic (PK/PD) profile, and poor penetration in the complex environment of lung cancer cells. Thus, the present study aims to formulate GmcH loaded mannosylated solid lipid nanoparticles (GmcH-SLNs) for improving its drug uptake into the lung cancer cells. GmcH-SLNs were prepared by emulsification and solvent evaporation process, and surface modification was done with mannose using ring opening technique. The cellular toxicity and cell uptake studies were performed in A549 lung adenocarcinoma cell line. The developed nanoformulation appears to be proficient in targeted delivery of GmcH with improved therapeutic effectiveness and enhanced safety.

Matched MeSH terms: Mannose/chemistry*
Biomass burning as the main source of organic aerosol particulate matter in Malaysia during haze episodes

Radzi bin Abas M, Oros DR, Simoneit BR

Chemosphere, 2004 May;55(8):1089-95.
PMID: 15050806

The haze episodes that occurred in Malaysia in September-October 1991, August-October 1994 and September-October 1997 have been attributed to suspended smoke particulate matter from biomass burning in southern Sumatra and Kalimantan, Indonesia. In the present study, polar organic compounds in aerosol particulate matter from Malaysia are converted to their trimethylsilyl derivatives and analyzed by gas chromatography-mass spectrometry in order to better assess the contribution of the biomass burning component during the haze episodes. On the basis of this analysis, levoglucosan was found to be the most abundant organic compound detected in almost all samples. The monosaccharides, alpha- and beta-mannose, the lignin breakdown products, vanillic and syringic acids and the minor steroids, cholesterol and beta-sitosterol were also present in some samples. The presence of the tracers from smoke overwhelmed the typical signatures of emissions from traffic and other anthropogenic activities in the urban areas.

Matched MeSH terms: Mannose
Distribution, sources and potential health risks of polycyclic aromatic hydrocarbons (PAHs) in PM2.5 collected during different monsoon seasons and haze episode in Kuala Lumpur

Sulong NA, Latif MT, Sahani M, Khan MF, Fadzil MF, Tahir NM, et al.

Chemosphere, 2019 Mar;219:1-14.
PMID: 30528968 DOI: 10.1016/j.chemosphere.2018.11.195

This study aimed to determine the distribution and potential health risks of polycyclic aromatic hydrocarbons (PAHs) in PM2.5 collected in Kuala Lumpur during different monsoon seasons. The potential sources of PM2.5 were investigated using 16 priority PAHs with additional of biomass tracers namely levoglucosan (LV), mannosan (MN) and galactosan (GL). This study also investigated the cytotoxic potential of the extracted PAHs towards V79-4 cells. A high-volume air sampler (HVS) was used to collect PM2.5 samples for 24 h. PAHs were extracted using dichloromethane (DCM) while biomass tracers were extracted by a mixture of DCM/methanol (3:1) before analysis with gas chromatography-mass spectrometry (GC-MS). The cytotoxicity of the PAHs extract was determined by assessing the cell viability through the reduction of tetrazolium salts (MTT). The results showed that the total mean ± SD concentrations of PAHs during the southwest (SW) and northeast (NE) monsoons were 2.51 ± 0.93 ng m-3 and 1.37 ± 0.09 ng m-3, respectively. Positive matrix factorization (PMF) using PAH and biomass tracer concentrations suggested four potential sources of PM2.5; gasoline emissions (29.1%), natural gas and coal burning (28.3%), biomass burning (22.3%), and diesel and heavy oil combustion (20.3%). Health risk assessment showed insignificant incremental lifetime cancer risk (ILCR) of 2.40E-07 for 70 years of exposure. MTT assay suggested that PAHs extracts collected during SW monsoon have cytotoxic effect towards V79-4 cell at the concentrations of 25 μg mL-1, 50 μg mL-1, 100 μg mL-1 whereas non-cytotoxic effect was observed on the PAHs sample collected during NE monsoon.

Matched MeSH terms: Mannose
Fulltext The use of chemotherapeutic agents as prophylaxis for recurrent urinary tract infection in healthy nonpregnant women: A network meta-analysis

Nalliah S, Fong JSH, Yi Thor AY, Lim OH

Indian J Urol, 2019 4 20;35(2):147-155.
PMID: 31000921 DOI: 10.4103/iju.IJU_378_18

Introduction: The aim of this systematic review is to compare chemotherapeutic agents commonly used in treating recurrent urinary infection in nonpregnant women by their efficacy, tolerability, adverse effects, and cost employing network meta-analysis.
Materials and Methods: We used three online databases, i.e., PubMed, ScienceDirect, and Cochrane Central Registry of Clinical Trials. Randomized controlled trials (RCTs) on the use of prophylactic chemotherapeutic agents used in treating nonpregnant women with recurrent urinary tract infections (RUTIs) published between 2002 and 2016 were selected. Only published papers in English were assessed for study quality, and meta-analyses were performed using fixed-effects model with NetMetaXL.
Results: Six RCTs fulfilled the criteria. When all three variables, i.e., efficacy, adverse effects and cost were considered, nitrofurantoin 50 mg once daily for 6 months appears to rank high for prophylaxis against RUTI. When efficacy was the only factor, fosfomycin had the highest superiority compared to D-mannose, nitrofurantoin, estriol, trimethoprim-sulfamethoxazole, and cranberry juice, respectively. However, fosfomycin was also ranked highest by adverse events. When cost alone is considered, nitrofurantoin appeared the most cost-effective agent while placed third for efficacy alone.
Conclusion: Selecting appropriate chemotherapeutic agents for RUTI will need to factor in effectiveness, adverse effects, and cost. While it is difficult to select an ideal drug, evaluation using network analysis may guide choice of medication for best practice.

Matched MeSH terms: Mannose

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