Displaying publications 241 - 260 of 322 in total

Abstract:
Sort:
  1. da Fonseca RR, Couto A, Machado AM, Brejova B, Albertin CB, Silva F, et al.
    Gigascience, 2020 Jan 01;9(1).
    PMID: 31942620 DOI: 10.1093/gigascience/giz152
    BACKGROUND: The giant squid (Architeuthis dux; Steenstrup, 1857) is an enigmatic giant mollusc with a circumglobal distribution in the deep ocean, except in the high Arctic and Antarctic waters. The elusiveness of the species makes it difficult to study. Thus, having a genome assembled for this deep-sea-dwelling species will allow several pending evolutionary questions to be unlocked.

    FINDINGS: We present a draft genome assembly that includes 200 Gb of Illumina reads, 4 Gb of Moleculo synthetic long reads, and 108 Gb of Chicago libraries, with a final size matching the estimated genome size of 2.7 Gb, and a scaffold N50 of 4.8 Mb. We also present an alternative assembly including 27 Gb raw reads generated using the Pacific Biosciences platform. In addition, we sequenced the proteome of the same individual and RNA from 3 different tissue types from 3 other species of squid (Onychoteuthis banksii, Dosidicus gigas, and Sthenoteuthis oualaniensis) to assist genome annotation. We annotated 33,406 protein-coding genes supported by evidence, and the genome completeness estimated by BUSCO reached 92%. Repetitive regions cover 49.17% of the genome.

    CONCLUSIONS: This annotated draft genome of A. dux provides a critical resource to investigate the unique traits of this species, including its gigantism and key adaptations to deep-sea environments.

    Matched MeSH terms: Tandem Mass Spectrometry
  2. Al-Wajeeh AS, Salhimi SM, Al-Mansoub MA, Khalid IA, Harvey TM, Latiff A, et al.
    PLoS One, 2020;15(1):e0227404.
    PMID: 31945087 DOI: 10.1371/journal.pone.0227404
    BACKGROUND: Breast cancer is the fifth most prevalent cause of death among women worldwide. It is also one of the most common types of cancer among Malaysian women. This study aimed to characterize and differentiate the proteomics profiles of different stages of breast cancer and its matched adjacent normal tissues in Malaysian breast cancer patients. Also, this study aimed to construct a pertinent protein pathway involved in each stage of cancer.

    METHODS: In total, 80 samples of tumor and matched adjacent normal tissues were collected from breast cancer patients at Seberang Jaya Hospital (SJH) and Kepala Batas Hospital (KBH), both in Penang, Malaysia. The protein expression profiles of breast cancer and normal tissues were mapped by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The Gel-Eluted Liquid Fractionation Entrapment Electrophoresis (GELFREE) Technology System was used for the separation and fractionation of extracted proteins, which also were analyzed to maximize protein detection. The protein fractions were then analyzed by tandem mass spectrometry (LC-MS/MS) analysis using LC/MS LTQ-Orbitrap Fusion and Elite. This study identified the proteins contained within the tissue samples using de novo sequencing and database matching via PEAKS software. We performed two different pathway analyses, DAVID and STRING, in the sets of proteins from stage 2 and stage 3 breast cancer samples. The lists of molecules were generated by the REACTOME-FI plugin, part of the CYTOSCAPE tool, and linker nodes were added in order to generate a connected network. Then, pathway enrichment was obtained, and a graphical model was created to depict the participation of the input proteins as well as the linker nodes.

    RESULTS: This study identified 12 proteins that were detected in stage 2 tumor tissues, and 17 proteins that were detected in stage 3 tumor tissues, related to their normal counterparts. It also identified some proteins that were present in stage 2 but not stage 3 and vice versa. Based on these results, this study clarified unique proteins pathways involved in carcinogenesis within stage 2 and stage 3 breast cancers.

    CONCLUSIONS: This study provided some useful insights about the proteins associated with breast cancer carcinogenesis and could establish an important foundation for future cancer-related discoveries using differential proteomics profiling. Beyond protein identification, this study considered the interaction, function, network, signaling pathway, and protein pathway involved in each profile. These results suggest that knowledge of protein expression, especially in stage 2 and stage 3 breast cancer, can provide important clues that may enable the discovery of novel biomarkers in carcinogenesis.

    Matched MeSH terms: Tandem Mass Spectrometry
  3. Li CMY, Briggs MT, Lee YR, Tin T, Young C, Pierides J, et al.
    Clin Exp Med, 2024 Mar 16;24(1):53.
    PMID: 38492056 DOI: 10.1007/s10238-024-01311-5
    Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. CRC liver metastases (CRLM) are often resistant to conventional treatments, with high rates of recurrence. Therefore, it is crucial to identify biomarkers for CRLM patients that predict cancer progression. This study utilised matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially map the CRLM tumour proteome. CRLM tissue microarrays (TMAs) of 84 patients were analysed using tryptic peptide MALDI-MSI to spatially monitor peptide abundances across CRLM tissues. Abundance of peptides was compared between tumour vs stroma, male vs female and across three groups of patients based on overall survival (0-3 years, 4-6 years, and 7+ years). Peptides were then characterised and matched using LC-MS/MS. A total of 471 potential peptides were identified by MALDI-MSI. Our results show that two unidentified m/z values (1589.876 and 1092.727) had significantly higher intensities in tumours compared to stroma. Ten m/z values were identified to have correlation with biological sex. Survival analysis identified three peptides (Histone H4, Haemoglobin subunit alpha, and Inosine-5'-monophosphate dehydrogenase 2) and two unidentified m/z values (1305.840 and 1661.060) that were significantly higher in patients with shorter survival (0-3 years relative to 4-6 years and 7+ years). This is the first study using MALDI-MSI, combined with LC-MS/MS, on a large cohort of CRLM patients to identify the spatial proteome in this malignancy. Further, we identify several protein candidates that may be suitable for drug targeting or for future prognostic biomarker development.
    Matched MeSH terms: Tandem Mass Spectrometry
  4. Gasull M, Pumarega J, Kiviranta H, Rantakokko P, Raaschou-Nielsen O, Bergdahl IA, et al.
    Environ Res, 2019 Feb;169:417-433.
    PMID: 30529143 DOI: 10.1016/j.envres.2018.11.027
    BACKGROUND: The use of biomarkers of environmental exposure to explore new risk factors for pancreatic cancer presents clinical, logistic, and methodological challenges that are also relevant in research on other complex diseases.

    OBJECTIVES: First, to summarize the main design features of a prospective case-control study -nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort- on plasma concentrations of persistent organic pollutants (POPs) and pancreatic cancer risk. And second, to assess the main methodological challenges posed by associations among characteristics and habits of study participants, fasting status, time from blood draw to cancer diagnosis, disease progression bias, basis of cancer diagnosis, and plasma concentrations of lipids and POPs. Results from etiologic analyses on POPs and pancreatic cancer risk, and other analyses, will be reported in future articles.

    METHODS: Study subjects were 1533 participants (513 cases and 1020 controls matched by study centre, sex, age at blood collection, date and time of blood collection, and fasting status) enrolled between 1992 and 2000. Plasma concentrations of 22 POPs were measured by gas chromatography - triple quadrupole mass spectrometry (GC-MS/MS). To estimate the magnitude of the associations we calculated multivariate-adjusted odds ratios by unconditional logistic regression, and adjusted geometric means by General Linear Regression Models.

    RESULTS: There were differences among countries in subjects' characteristics (as age, gender, smoking, lipid and POP concentrations), and in study characteristics (as time from blood collection to index date, year of last follow-up, length of follow-up, basis of cancer diagnosis, and fasting status). Adjusting for centre and time of blood collection, no factors were significantly associated with fasting status. Plasma concentrations of lipids were related to age, body mass index, fasting, country, and smoking. We detected and quantified 16 of the 22 POPs in more than 90% of individuals. All 22 POPs were detected in some participants, and the smallest number of POPs detected in one person was 15 (median, 19) with few differences by country. The highest concentrations were found for p,p'-DDE, PCBs 153 and 180 (median concentration: 3371, 1023, and 810 pg/mL, respectively). We assessed the possible occurrence of disease progression bias (DPB) in eight situations defined by lipid and POP measurements, on one hand, and by four factors: interval from blood draw to index date, tumour subsite, tumour stage, and grade of differentiation, on the other. In seven of the eight situations results supported the absence of DPB.

    CONCLUSIONS: The coexistence of differences across study centres in some design features and participant characteristics is of relevance to other multicentre studies. Relationships among subjects' characteristics and among such characteristics and design features may play important roles in the forthcoming analyses on the association between plasma concentrations of POPs and pancreatic cancer risk.

    Matched MeSH terms: Tandem Mass Spectrometry
  5. Abdullah AR, Hapidin H, Abdullah H
    PMID: 29861772 DOI: 10.1155/2018/5319528
    Background. Quercus infectoria (QI) is a plant used in traditional medicines in Asia. The plant was reported to contain various active phytochemical compounds that have potential to stimulate bone formation. However, the precise mechanism of the stimulation effect of QI on osteoblast has not been elucidated. The present study was carried out to isolate QI semipurified fractions from aqueous QI extract and to delineate the molecular mechanism of QI semipurified fraction that enhanced bone formation by using hFOB1.19 human fetal osteoblast cell model. Methods. Isolation of QI semipurified fractions was established by means of column chromatography and thin layer chromatography. Established QI semipurified fractions were identified using Liquid Chromatography-Mass Spectrometry (LC-MS). Cells were treated with derived QI semipurified fractions and investigated for mineralization deposition and protein expression level of BMP-2, Runx2, and OPN by ELISA followed gene expression analysis of BMP-2 and Runx2 by RT-PCR. Results. Column chromatography isolation and purification yield Fractions A, B, and C. LC-MS analysis reveals the presence of polyphenols in each fraction. Results show that QI semipurified fractions increased the activity and upregulated the gene expression of BMP-2 and Runx2 at day 1, day 3, and day 7. OPN activity increased in cells treated with QI semipurified fractions at day 1 and day 3. Meanwhile, at day 7, expression of OPN decreased in activity. Furthermore, the study showed that combination of Fractions A, B, and C with osteoporotic drug (pamidronate) further increased the activity and upregulated the gene expression of BMP-2 and Runx2. Conclusions. These findings demonstrated that polyphenols from semipurified fractions of QI enhanced bone formation through expression of the investigated bone-related marker that is its potential role when combined with readily available osteoporotic drug.
    Matched MeSH terms: Tandem Mass Spectrometry
  6. Khazaei S, Abdul Hamid R, Ramachandran V, Mohd Esa N, Pandurangan AK, Danazadeh F, et al.
    PMID: 29250124 DOI: 10.1155/2017/1468957
    Breast cancer is the second leading cause of cancer death among women and despite significant advances in therapy, it remains a critical health problem worldwide. Allium atroviolaceum is an herbaceous plant, with limited information about the therapeutic capability. We aimed to study the anticancer effect of flower extract and the mechanisms of action in MCF-7 and MDA-MB-231. The extract inhibits the proliferation of the cells in a time- and dose-dependent manner. The underlying mechanism involved the stimulation of S and G2/M phase arrest in MCF-7 and S phase arrest in MDA-MB-231 associated with decreased level of Cdk1, in a p53-independent pathway. Furthermore, the extract induces apoptosis in both cell lines, as indicated by the percentage of sub-G0 population, the morphological changes observed by phase contrast and fluorescent microscopy, and increase in Annexin-V-positive cells. The apoptosis induction was related to downregulation of Bcl-2 and also likely to be caspase-dependent. Moreover, the combination of the extract and tamoxifen exhibits synergistic effect, suggesting that it can complement current chemotherapy. LC-MS analysis displayed 17 major compounds in the extract which might be responsible for the observed effects. Overall, this study demonstrates the potential applications of Allium atroviolaceum extract as an anticancer drug for breast cancer treatment.
    Matched MeSH terms: Tandem Mass Spectrometry
  7. Memon AH, Ismail Z, Aisha AF, Al-Suede FS, Hamil MS, Hashim S, et al.
    PMID: 25530783 DOI: 10.1155/2014/470179
    Syzygium campanulatum Korth is an equatorial, evergreen, aboriginal shrub of Malaysia. Conventionally it has been used as a stomachic. However, in the currently conducted study dimethyl cardamonin or 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC) was isolated from S. campanulatum Korth, leaf extract. The structural characterization of DMC was carried out by making use of various techniques including UV, IR, NMR spectral followed by LC-MS, and X-ray crystallographic techniques. For determining the purity of compound, highly effective techniques including TLC, HPLC, and melting point were used. The cytotoxicity of DMC and three different extracts of S. campanulatum was evaluated against human colon cancer cell line (HT-29) by three different assays. DMC and ethanolic extract revealed potent and dose-dependent cytotoxic activity on the cancer cell line with IC50 12.6 and 90.1 µg/mL, respectively. Quite astonishingly to our knowledge, this is the very first report on S. campanulatum as being a rich source (3.5%) of DMC, X-ray crystallography, and anticancer activity on human colon cancer cells.
    Matched MeSH terms: Tandem Mass Spectrometry
  8. Wu XY, Zhao ZY, Osman EEA, Wang XJ, Choo YM, Benjamin MM, et al.
    Bioorg Chem, 2024 Feb;143:107103.
    PMID: 38211549 DOI: 10.1016/j.bioorg.2024.107103
    Three undescribed (1-3) and nine known (4-12) platanosides were isolated and characterized from a bioactive extract of the May leaves of Platanus × acerifolia that initially showed inhibition against Staphylococcus aureus. Targeted compound mining was guided by an LC-MS/MS-based molecular ion networking (MoIN) strategy combined with conventional isolation procedures from a unique geographic location. The novel structures were mainly determined by 2D NMR and computational (NMR/ECD calculations) methods. Compound 1 is a rare acylated kaempferol rhamnoside possessing a truxinate unit. 6 (Z,E-platanoside) and 7 (E,E-platanoside) were confirmed to have remarkable inhibitory effects against both methicillin-resistant S. aureus (MIC: ≤ 16 μg/mL) and glycopeptide-resistant Enterococcus faecium (MIC: ≤ 1 μg/mL). These platanosides were subjected to docking analyses against FabI (enoyl-ACP reductase) and PBP1/2 (penicillin binding protein), both of which are pivotal enzymes governing bacterial growth but not found in the human host. The results showed that 6 and 7 displayed superior binding affinities towards FabI and PBP2. Moreover, surface plasmon resonance studies on the interaction of 1/7 and FabI revealed that 7 has a higher affinity (KD = 1.72 μM), which further supports the above in vitro data and is thus expected to be a novel anti-antibacterial drug lead.
    Matched MeSH terms: Tandem Mass Spectrometry
  9. Bourais I, Elmarrkechy S, Taha D, Badaoui B, Mourabit Y, Salhi N, et al.
    Molecules, 2022 Dec 16;27(24).
    PMID: 36558122 DOI: 10.3390/molecules27248989
    Leaves, husk, kernels, and bark methanolic extracts of Juglans regia L. were tested for their in vitro antidiabetic, anti-inflammatory, and antioxidant activities. For these purposes, α-amylase and α-glucosidase were used as the main enzymes to evaluate antidiabetic activities. Moreover, lipoxidase and tyrosinase activities were tested to estimate anti-inflammatory properties. Antioxidant properties of Juglans regia L., extracts were determined using three different assays. Leaves extract has an important radical scavenging activity and a-amylase inhibition. Similarly, husk extracts showed high total phenolic content (306.36 ± 4.74 mg gallic acid equivalent/g dry extract) with an important α-amylase inhibition (IC50 = 75.42 ± 0.99 µg/mL). Kernels exhibit significant tyrosinase (IC50 = 51.38 ± 0.81 µg/mL) correlated with antioxidant activities (p < 0.05). Husk and bark extracts also showed strong anti-lipoxidase activities with IC50 equal to 29.48 ± 0.28 and 28.58 ± 0.35 µg/mL, respectively. HPLC-DAD-ESI-MS/MS analysis highlights the phenolic profile of methanolic extracts of Juglans regia L. plant parts. The identified polyphenols were known for their antioxidant, antidiabetic (dicaffeoyl-quinic acid glycoside in kernels), and anti-inflammatory (3,4-dihydroxybenzoic acid in leaves) activities. Further investigations are needed to determine molecular mechanisms involved in these effects as well as to study the properties of the main identified compounds.
    Matched MeSH terms: Tandem Mass Spectrometry
  10. Nordin MA, Wan Harun WH, Abdul Razak F, Musa MY
    Int J Oral Sci, 2014 Mar;6(1):15-21.
    PMID: 24406634 DOI: 10.1038/ijos.2013.97
    Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg⋅mL(-1); (iii) 3 mg⋅mL(-1); and (iv) 6 mg⋅mL(-1). The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×10(6) to 1.78×10(6) viable cell counts (CFU)⋅mL(-1). SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.
    Matched MeSH terms: Tandem Mass Spectrometry/methods
  11. Mohamed SIA, Jantan I, Nafiah MA, Seyed MA, Chan KM
    Curr Pharm Biotechnol, 2021;22(2):262-273.
    PMID: 32532192 DOI: 10.2174/1389201021666200612173029
    BACKGROUND: The anticancer effects of Phyllanthus amarus extract on various cancer cells have been investigated, however, the effects of its major constituents on HCT116 human colorectal cancer cells have not been reported.

    OBJECTIVE: In the present study, we investigated the cytotoxic effect of 80% ethanol extract of P. amarus and its marker constituents (phyllanthin, hypophyllanthin, gallic acid, niranthin, greraniin, phyltetralin, isolintetralin, corilagin and ellagic acid) on HCT116 and their underlying mechanisms of action.

    METHODS: Their antiproliferative and apoptotic effects on HCT 116 were performed using MTT assay and flow cytometric analysis, respectively, while caspases 3/7, 8 and 9 activities were examined using the colorimetric method. The expression of cleaved poly ADP ribose polymerase enzyme (PARP) and cytochrome c proteins was investigated by the immune-blot technique.

    RESULTS AND DISCUSSION: HPLC and LC-MS/MS analyses demonstrated that the extract contained mainly lignans and polyphenols. The plant samples markedly suppressed the growth and expansion of HCT116 cells in a concentration- and time-dependent manner with no toxicity against normal human fibroblast CCD18 Co. P. amarus extract, phyllanthin and gallic acid induced mode of cell death primarily through apoptosis as confirmed by the exteriorization of phosphatidylserine. Caspases 3/7, 8, and 9 activities increased in a concentration-dependent manner following 24h treatment. The expressions of cleaved PARP (Asp 214) and cytochrome c were markedly upregulated.

    CONCLUSION: P. amarus extract, phyllanthin and gallic acid exhibited an apoptotic effect on HCT116 cells through the caspases-dependent pathway.

    Matched MeSH terms: Tandem Mass Spectrometry/methods
  12. Okechukwu PN, Ekeuku SO, Chan HK, Eluri K, Froemming GRA
    Curr Pharm Biotechnol, 2021;22(2):288-298.
    PMID: 32744968 DOI: 10.2174/1389201021666200730124208
    BACKGROUND: Diabetes Mellitus (DM) is characterized by hyperglycemia (high blood glucose levels) which is due to the destruction of insulin-producing β-cells in the islets of Langerhans in the pancreas. It is associated with oxidative and endoplasmic reticulum stress. The plant alkaloid Palmatine has been previously reported to possess antidiabetic and antioxidant properties as well as other protective properties against kidney and liver tissue damage.

    OBJECTIVE: Here, we investigated the ability of Palmatine to reduce the up-regulation of chaperone proteins Glucose Regulatory Protein 78 (GRP78), and Calreticulin (CALR) protein in a Streptozotocin (STZ)-induced diabetic rat model.

    METHODS: Streptozotocin (STZ) induced diabetes in Sprague Dawley rats treated with 2mg/kg of Palmatine for 12 weeks after the elevation of plasma glucose levels above 11mmol/L post-STZ administration. Proteins were extracted from the pancreas after treatment and Two-Dimensional gel electrophoresis (2-DE), PDQuest 2-D analysis software genomic solutions and mass spectrometer were used to analyze differentially expressed protein. Mass Spectrometry (MS/MS), Multidimensional Protein Identification Technology (MudPIT) was used for protein identification.

    RESULTS: There was an up-regulation of the expression of chaperone proteins CALR and GRP78 and down-regulation of the expression of antioxidant and protection proteins peroxidoxin 4 (Prdx4), protein disulfide isomerase (PDIA2/3), Glutathione-S-Transferase (GSTs), and Serum Albumin (ALB) in non-diabetic rats. Palmatine treatment down-regulated the expression of chaperone proteins CALR and GRP78 and up-regulated the expression of Prdx4, PDIA2/3, GST, and ALB.

    CONCLUSION: Palmatine may have activated antioxidant proteins, which protected the cells against reactive oxygen species and endoplasmic stress. The result is in consonance with our previous report on Palmatine.

    Matched MeSH terms: Tandem Mass Spectrometry/methods
  13. Khoo LW, Kow ASF, Maulidiani M, Ang MY, Chew WY, Lee MT, et al.
    Phytochem Anal, 2019 Jan;30(1):46-61.
    PMID: 30183131 DOI: 10.1002/pca.2789
    INTRODUCTION: Clinacanthus nutans, a small shrub that is native to Southeast Asia, is commonly used in traditional herbal medicine and as a food source. Its anti-inflammation properties is influenced by the metabolites composition, which can be determined by different binary extraction solvent ratio and extraction methods used during plant post-harvesting stage.

    OBJECTIVE: Evaluate the relationship between the chemical composition of C. nutans and its anti-inflammatory properties using nuclear magnetic resonance (NMR) metabolomics approach.

    METHODOLOGY: The anti-inflammatory effect of C. nutans air-dried leaves extracted using five different binary extraction solvent ratio and two extraction methods was determined based on their nitric oxide (NO) inhibition effect in lipopolysaccharide-interferon-gamma (LPS-IFN-γ) activated RAW 264.7 macrophages. The relationship between extract bioactivity and metabolite profiles and quantifications were established using 1 H-NMR metabolomics and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The possible metabolite biosynthesis pathway was constructed to further strengthen the findings.

    RESULTS: Water and sonication prepared air-dried leaves possessed the highest NO inhibition activity (IC50  = 190.43 ± 12.26 μg/mL, P 

    Matched MeSH terms: Tandem Mass Spectrometry/methods
  14. Baskaran G, Salvamani S, Ahmad SA, Shaharuddin NA, Pattiram PD, Shukor MY
    Drug Des Devel Ther, 2015;9:509-17.
    PMID: 25609924 DOI: 10.2147/DDDT.S75056
    The enzyme 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase is the key enzyme of the mevalonate pathway that produces cholesterol. Inhibition of HMG-CoA reductase reduces cholesterol biosynthesis in the liver. Synthetic drugs, statins, are commonly used for the treatment of hypercholesterolemia. Due to the side effects of statins, natural HMG-CoA reductase inhibitors of plant origin are needed. In this study, 25 medicinal plant methanol extracts were screened for anti-HMG-CoA reductase activity. Basella alba leaf extract showed the highest inhibitory effect at about 74%. Thus, B. alba was examined in order to investigate its phytochemical components. Gas chromatography with tandem mass spectrometry and reversed phase high-performance liquid chromatography analysis revealed the presence of phenol 2,6-bis(1,1-dimethylethyl), 1-heptatriacotanol, oleic acid, eicosyl ester, naringin, apigenin, luteolin, ascorbic acid, and α-tocopherol, which have been reported to possess antihypercholesterolemic effects. Further investigation of in vivo models should be performed in order to confirm its potential as an alternative treatment for hypercholesterolemia and related cardiovascular diseases.
    Matched MeSH terms: Tandem Mass Spectrometry
  15. Goh SY, Tan WS, Khan SA, Chew HP, Abu Kasim NH, Yin WF, et al.
    Sensors (Basel), 2014;14(5):8940-9.
    PMID: 24854358 DOI: 10.3390/s140508940
    Bacteria realize the ability to communicate by production of quorum sensing (QS) molecules called autoinducers, which regulate the physiological activities in their ecological niches. The oral cavity could be a potential area for the presence of QS bacteria. In this study, we report the isolation of a QS bacterial isolate C10B from dentine caries. Preliminary screening using Chromobacterium violaceum CV026 biosensor showed that isolate C10B was able to produce N-acylhomoserine lactones (AHLs). This bacterium was further identified as a member of Burkholderia, an opportunistic pathogen. The isolated Burkholderia sp. was confirmed to produce N-hexanoyl-L-homoserine lactone (C6-HSL), N-octanoyl-L-homoserine lactone (C8-HSL), N-decanoyl-L-homoserine lactone (C10-HSL) and N-dodecanoyl-L-homoserine lactone (C12-HSL).
    Matched MeSH terms: Tandem Mass Spectrometry
  16. Lau CC, Abdullah N, Shuib AS
    BMC Complement Altern Med, 2013 Nov 11;13:313.
    PMID: 24215325 DOI: 10.1186/1472-6882-13-313
    BACKGROUND: Angiotensin I-converting enzyme (ACE) inhibitors have been reported to reduce mortality in patients with hypertension. Compared to chemosynthetic drugs, ACE inhibitors derived from natural sources such as food proteins are believed to be safer for consumption and to have fewer adverse effects. Some edible mushrooms have been reported to significantly reduce blood pressure after oral administration. In addition, mushrooms are known to be rich in protein content. This makes them a potential source of ACE inhibitory peptides. Hence, the objective of the current study was to isolate and characterise ACE inhibitory peptides from an edible mushroom, Pleurotus cystidiosus.

    METHODS: ACE inhibitory proteins were isolated from P. cystidiosus based on the bioassay guided purification steps, i.e. ammonium sulphate precipitation, reverse phase high performance liquid chromatography and size exclusion chromatography. Active fraction was then analysed by LC-MS/MS and potential ACE inhibitory peptides identified were chemically synthesized. Effect of in vitro gastrointestinal digestions on the ACE inhibitory activity of the peptides and their inhibition patterns were evaluated.

    RESULTS: Two potential ACE inhibitory peptides, AHEPVK and GPSMR were identified from P. cystidiosus with molecular masses of 679.53 and 546.36 Da, respectively. Both peptides exhibited potentially high ACE inhibitory activity with IC50 values of 62.8 and 277.5 μM, respectively. SEC chromatograms and BIOPEP analysis of these peptides revealed that the peptide sequence of the hexapeptide, AHEPVK, was stable throughout gastrointestinal digestion. The pentapeptide, GPSMR, was hydrolysed after digestion and it was predicted to release a dipeptide ACE inhibitor, GP, from its precursor. The Lineweaver-Burk plot of AHEPVK showed that this potent and stable ACE inhibitor has a competitive inhibitory effect against ACE.

    CONCLUSION: The present study indicated that the peptides from P. cystidiosus could be potential ACE inhibitors. Although these peptides had lower ACE inhibitory activity compared to commercial antihypertensive drugs, they are derived from mushroom which could be easily obtained and should have no side effects. Further in vivo studies can be carried out to reveal the clear mechanism of ACE inhibition by these peptides.

    Matched MeSH terms: Tandem Mass Spectrometry
  17. Lee SH, Jaganath IB, Wang SM, Sekaran SD
    PLoS One, 2011;6(6):e20994.
    PMID: 21698198 DOI: 10.1371/journal.pone.0020994
    Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells.
    Matched MeSH terms: Tandem Mass Spectrometry
  18. Lim SR, Gooi BH, Gam LH
    Cancer Biomark, 2012;12(4):185-98.
    PMID: 23568009 DOI: 10.3233/CBM-130307
    Detection of low abundance proteins always possesses challenges even with the currently available proteomics technologies.
    Matched MeSH terms: Tandem Mass Spectrometry
  19. Jayapalan JJ, Ng KL, Shuib AS, Razack AH, Hashim OH
    Electrophoresis, 2013 Jun;34(11):1663-9.
    PMID: 23417432 DOI: 10.1002/elps.201200583
    The present study was aimed at the identification of proteins that are differentially expressed in the urine of patients with prostate cancer (PCa), those with benign prostatic hyperplasia (BPH) and age-matched healthy male control subjects. Using a combination of 2DE and MS/MS, significantly lower expression of urinary saposin B and two different fragments of inter-alpha-trypsin inhibitor light chain (ITIL) was demonstrated in the PCa patients compared to the controls. However, only one of the ITIL fragments was significantly different between the PCa and BPH patients. When image analysis was performed on urinary proteins that were transferred onto NC membranes and detected using a lectin that binds to O-glycans, a truncated fragment of inter-alpha-trypsin inhibitor heavy chain 4 was the sole protein found to be significantly enhanced in the PCa patients compared to the controls. Together, these urinary peptide fragments might be useful complementary biomarkers to indicate PCa as well as to distinguish it from BPH, although further epidemiological evidence on the specificity and sensitivity of the protein candidates is required.
    Matched MeSH terms: Tandem Mass Spectrometry
  20. Munusamy K, Loke MF, Vadivelu J, Tay ST
    Microb Pathog, 2021 Mar;152:104614.
    PMID: 33202254 DOI: 10.1016/j.micpath.2020.104614
    Candidiasis is the most common fungal infection associated with high morbidity and mortality among immunocompromised patients. The ability to form biofilm is essential for Candida albicans pathogenesis and drug resistance. In this study, the planktonic cell and biofilm proteomes of C. albicans SC5314 strain analyzed using Liquid Chromatography-Mass Spectrometry (LC-MS) were compared. In total, 280 and 449 proteins are annotated from the planktonic cell and biofilm proteomes, respectively. The biofilm proteome demonstrated significantly higher proportion of proteins associated with the endomembrane system, mitochondrion and cytoplasm than planktonic proteome. Among proteins detected, 143 and 207 biological processes are annotated, of which, 38 and 102 are specific to the planktonic cell and biofilm proteomes, respectively, while 105 are common biological processes. The specific biological processes of C. albicans planktonic cell proteome are associated with cell polarity, energy metabolism and nucleotide (purine) metabolism, oxido-reduction coenzyme metabolic process, monosaccharide and amino acid (methionine) biosynthesis, regulation of anatomical structure morphogenesis and cell cycling, and single organism reproduction. Meanwhile, regulation of cellular macromolecule biosynthesis and metabolism, transcription and gene expression are major biological processes specifically associated with C. albicans biofilm proteome. Biosynthesis of leucine, isoleucine, and thiocysteine are highlighted as planktonic-related pathways, whereas folate metabolism, fatty acid metabolism and biosynthesis of amino acids (lysine, serine and glycine) are highlighted as biofilm-related pathways. In summary, LC-MS-based proteomic analysis reveals different adaptative strategies of C. albicans via specific biological and metabolic processes for planktonic cell and biofilm lifestyles. The mass spectrometry data are available via ProteomeXchange with identifiers PXD007830 (for biofilm proteome) and PXD007831 (for planktonic cell proteome).
    Matched MeSH terms: Tandem Mass Spectrometry
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links