Displaying publications 361 - 380 of 522 in total

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  1. Simarmata D, Ng DC, Kam YW, Lee B, Sum MS, Her Z, et al.
    Sci Rep, 2016 05 16;6:26097.
    PMID: 27180811 DOI: 10.1038/srep26097
    Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown. In this study, we analyzed the clinical and immunological response, focusing on the cytokine/chemokine profile in a CHIKV-infected pediatric cohort from Sarawak, Malaysia. Unique immune mediators triggered upon CHIKV infection were identified through meta-analysis of the immune signatures between this pediatric group and cohorts from previous outbreaks. The data generated from this study revealed that a broad spectrum of cytokines/chemokines is up-regulated in a sub-group of virus-infected children stratified according to their viremic status during hospitalization. Furthermore, different immune mediator profiles (the levels of pro-inflammatory cytokines, chemokines and growth and other factors) were observed between children and adults. This study gives an important insight to understand the immune response of CHIKV infection in children and would aid in the development of better prognostics and clinical management for children.
    Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
  2. Syva SH, Ampon K, Lasimbang H, Fatimah SS
    J Tissue Eng Regen Med, 2017 02;11(2):311-320.
    PMID: 26073746 DOI: 10.1002/term.2043
    Human amnion mesenchymal stem cells (HAMCs) show great differentiation and proliferation potential and also other remarkable features that could serve as an outstanding alternative source of stem cells in regenerative medicine. Recent reports have demonstrated various kinds of effective artificial niche that mimic the microenvironment of different types of stem cell to maintain and control their fate and function. The components of the stem cell microenvironment consist mainly of soluble and insoluble factors responsible for regulating stem cell differentiation and self-renewal. Extensive studies have been made on regulating HAMCs differentiation into specific phenotypes; however, the understanding of relevant factors in directing stem cell fate decisions in HAMCs remain underexplored. In this review, we have therefore identified soluble and insoluble factors, including mechanical stimuli and cues from the other supporting cells that are involved in directing HAMCs fate decisions. In order to strengthen the significance of understanding on the relevant factors involved in stem cell fate decisions, recent technologies developed to specifically mimic the microenvironments of specific cell lineages are also reviewed. Copyright © 2015 John Wiley & Sons, Ltd.
    Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
  3. Rahim MA, Rahim ZH, Ahmad WA, Hashim OH
    Int J Med Sci, 2015;12(4):329-35.
    PMID: 25897294 DOI: 10.7150/ijms.11280
    Human saliva plays a pivotal role in digesting food and maintaining oral hygiene. The presence of electrolytes, mucus, glycoproteins, enzymes, antibacterial compounds, and gingival crevicular fluid in saliva ensures the optimum condition of oral cavity and general health condition. Saliva collection has been proven non-invasive, convenient, and inexpensive compared to conventional venipuncture procedure. These distinctive advantages provide a promising potential of saliva as a diagnostic fluid. Through comprehensive analysis, an array of salivary proteins and peptides may be beneficial as biomarkers in oral and systemic diseases. In this review, we discuss the utility of human salivary proteomes and tabulate the recent salivary biomarkers found in subjects with acute myocardial infarction as well as respective methods employed. In a clinical setting, since acute myocardial infarction contributes to large cases of mortality worldwide, an early intervention using these biomarkers will provide an effective solution to reduce global heart attack incidence particularly among its high-risk group of type-2 diabetes mellitus patients. The utility of salivary biomarkers will make the prediction of this cardiac event possible due to its reliability hence improve the quality of life of the patients. Current challenges in saliva collection are also addressed to improve the quality of saliva samples and produce robust biomarkers for future use in clinical applications.
    Matched MeSH terms: Salivary Proteins and Peptides/metabolism*
  4. Looi LM
    Malays J Pathol, 1995 Jun;17(1):1-10.
    PMID: 8906998
    Two forms of abnormal fibrillary protein deposition are considered: amyloidosis and fibrillary (immunotactoid) glomerulonephritis. Amyloid is characterised by an antiparallel, beta-pleated configuration which imparts to it a unique apple-green birefringence after Congo red staining. Inspite of its fairly constant physical properties, the chemical composition of amyloid fibrils is amazingly diverse, encomposing AA protein, light chain fragments, transthyretin, procalcitonin, islet amyloid polypeptide, atrial natriuretic peptides, beta-amyloid protein, beta-2-microglobulin, cystatin C, gelsolin, apolipoprotein A1, lyzozyme and their mutant variants. Amyloid P component and heparan sulphate proteoglycan are ubiquitous non-fibrillary amyloid components which have significant roles in the amyloidogenetic process, as do also precursor fibril proteins. Different amyloid fibril proteins relate to different amyloidosis syndromes and different histological patterns, and provide the basis for new diagnostic approaches to this disorder. Glomerular deposits in fibrillary glomerulonephritis (FGN), although often mistaken for amyloid, differ from it in its negative Congophilia, wider fibril width and highly organised, microtubular-tactoidal appearance ultrastructurally. FGN is essentially a primary glomerulopathy resulting in progressive renal failure. Despite certain differences, intriguing similarities between both entities of fibrillary deposition pose a challenge to researchers as to the mechanisms of abnormal protein crystallization and fibril formation in tissues.
    Matched MeSH terms: Amyloid beta-Peptides/chemistry
  5. Init I, Mak JW, Top S, Zulhainan Z, Prummongkol S, Nissapatorn V, et al.
    PMID: 15115079
    The objective of this study was to characterize the polypeptides associated with cysts of Blastocystis hominis. This form is believed to be infective and plays a role in parasite resistance to anti-B. hominis drugs currently used for treatment of Blastocystis associated diarrhea. Cysts were induced through in vitro culture of the parasite in complete medium supplemented with bacterial extract with trypticase, metronidazole or doxycycline. SDS-PAGE analysis showed almost similar polypeptide patterns of parasite extracts obtained from in vitro cultured parasites before and after exposure with the three supplements. Polypeptide bands at 76, 58.5, 48, 45, 40, 38, 32, 25 and 22 kDa were constantly seen in all antigenic preparations and no specific cyst-associated polypeptide was present. However, on immunoblot analysis, 3 out of 16 blastocystosis human sera identified a cyst-associated polypeptide at 60 kDa in all parasite extracts prepared from cultures with the three supplements. In addition, there were associated morphological changes detected in these parasites stained with acridine orange and observed under fluorescence microscopy. Metronidazole induced cyst forms (reddish cells) as early as 12 hours post-exposure; more cyst production (with stronger immunoblot bands) occurred after 24 hours exposure. However, cysts rupture with release and destruction of B. hominis daughters cells occurred after 48 hours exposure. Doxycycline induced less cyst-like forms at 24 hours (weaker 60 kDa band) and less destruction of the cysts (60 kDa band still present at 72 hours post exposure). Bacterial extract and trypticase also induced cysts at 12 hours with increasing numbers up to 72 hours exposure (corresponding increase in intensity of 60 kDa band from samples harvested at 12 to 72 hours post exposure) without any sign of deleterious effect on the parasite.
    Matched MeSH terms: Peptides/metabolism*
  6. Chun-Lai T, Murad S, Erlandsson MC, Hussein H, Sulaiman W, Dhaliwal JS, et al.
    Medicine (Baltimore), 2015 Jan;94(4):e468.
    PMID: 25634192 DOI: 10.1097/MD.0000000000000468
    Survivin is a biomarker of cancer known for its anti-apoptotic and cell-cycle regulating properties. In the context of non-cancer pathology, high levels of survivin may be measured in blood and synovial fluid of patients with rheumatoid arthritis (RA) and associate with early joint damage and poor therapy response. The aim of the study was to investigate the value of survivin measurements in blood for diagnosis of RA in the frame of the Malaysian epidemiological investigation of rheumatoid arthritis (MyEIRA) study. The study enrolled RA patients from eight rheumatology centres in Peninsular Malaysia. The healthy controls matched by age, gender and ethnicity were recruited on the community basis from the residential area of the patients. Levels of survivin were measured in blood of RA patients (n = 1233) and controls (n = 1566) by an enzyme-linked immuno-sorbent assay (ELISA). The risk for RA was calculated as odds ratio (OR) and 95% confidence intervals in the individuals with high levels of survivin. The risk was calculated in relation to antibodies against cyclic citrullinated peptides (ACPA), detected by ELISA and HLA-DRB1 shared epitope (SE) alleles, identified by the polymerase chain reaction using sequence specific oligonucleotide method. High levels of survivin were detected in 625 of 1233 (50.7%) RA cases and in 85 of 1566 (5.4%) controls, indicating its high specificity for RA. Survivin was association with an increase in RA risk in the patients having neither SE-alleles nor ACPA (OR = 5.40, 95% CI 3.81-7.66). For the patients combining survivin, SE, and ACPA, the estimated risk for RA was 16-folds higher compared to the survivin negative patients with SE and ACPA(OR = 16.21, 95% CI 5.70-46.18). To conclude, detection of survivin in blood provides a simple test to improve diagnostic and to increase predictability for RA.
    Matched MeSH terms: Peptides, Cyclic/immunology
  7. Ali Khan MS, Ahmed N, Misbah, Arifuddin M, Zakaria ZA, Al-Sanea MM, et al.
    Food Chem Toxicol, 2018 May;115:523-531.
    PMID: 29555329 DOI: 10.1016/j.fct.2018.03.021
    In view of the report on anti-nociceptive activity of Leathery Murdah, Terminalia coriacea {Roxb.} Wight & Arn. (Combretaceae) leaves, the present study was conducted to isolate the active constituents and identify the underlying mechanisms. The methanolic extract of T. coriacea leaves (TCLME) at doses 125, 250 and 500 mg/kg orally, was subjected to various in-vivo assays in acetic acid induced writhing and formalin induced paw-licking tests with aspirin (100 mg/kg) and morphine (5 mg/kg) as reference drugs. Three flavonoids, rutin, robinin and gossypetin 3-glucuronide 8-glucoside were isolated and characterized from TCLME for the first time. The extract showed significant (p 
    Matched MeSH terms: Opioid Peptides/metabolism
  8. Qiu Z, Shen Q, Jiang C, Yao L, Sun X, Li J, et al.
    Int J Nanomedicine, 2021;16:2311-2322.
    PMID: 33776435 DOI: 10.2147/IJN.S302396
    Background: Alzheimer's disease (AD) is a neurodegenerative chronic disorder that causes dementia and problems in thinking, cognitive impairment and behavioral changes. Amyloid-beta (Aβ) is a peptide involved in AD progression, and a high level of Aβ is highly correlated with severe AD. Identifying and quantifying Aβ levels helps in the early treatment of AD and reduces the factors associated with AD.

    Materials and Methods: This research introduced a dual probe detection system involving aptamers and antibodies to identify Aβ. Aptamers and antibodies were attached to the gold (Au) urchin and hybrid on the carbon nanohorn-modified surface. The nanohorn was immobilized on the sensor surface by using an amine linker, and then a Au urchin dual probe was immobilized.

    Results: This dual probe-modified surface enhanced the current flow during Aβ detection compared with the surface with antibody as the probe. This dual probe interacted with higher numbers of Aβ peptides and reached the detection limit at 10 fM with R2=0.992. Furthermore, control experiments with nonimmune antibodies, complementary aptamer sequences and control proteins did not display the current responses, indicating the specific detection of Aβ.

    Conclusion: Aβ-spiked artificial cerebrospinal fluid showed a similar response to current changes, confirming the selective identification of Aβ.

    Matched MeSH terms: Amyloid beta-Peptides/metabolism
  9. Chan EWL, Yeo ETY, Wong KWL, See ML, Wong KY, Gan SY
    Curr Alzheimer Res, 2019;16(3):251-260.
    PMID: 30819080 DOI: 10.2174/1567205016666190228124630
    BACKGROUND: Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder that eventually leads to severe cognitive impairment. Although the exact etiologies of AD still remain elusive, increasing evidence suggests that neuroinflammation cascades mediated by microglial cells are associated with AD. Piper sarmentosum Roxb. (PS) is a medicinal plant reported to possess various biological properties, including anti-inflammatory, anti-psychotic and anti-oxidant activity. However, little is known about the anti-inflammatory activity of PS roots despite their traditional use to treat inflammatory- mediated ailments.

    OBJECTIVE: This study aimed to evaluate the anti-inflammatory and neuroprotective properties of extracts obtained from the roots of PS against beta-amyloid (Aβ)-induced microglial toxicity associated with the production of pro-inflammatory mediators.

    METHOD: BV2 microglial cells were treated with hexane (RHXN), dichloromethane (RDCM), ethyl acetate (REA) and methanol (RMEOH) extracts of the roots of PS prior to activation by Aβ. The production and mRNA expression of pro-inflammatory mediators were evaluated by Griess reagent, ELISA kits and RT-qPCR respectively. The phosphorylation status of p38α MAPK was determined via western blot assay. BV2 conditioned medium was used to treat SH-SY5Y neuroblastoma cells and the neuroprotective effect was assessed using MTT assay.

    RESULTS: PS root extracts, in particular RMEOH significantly attenuated the production and mRNA expression of IL-1β, IL-6 and TNF-α in Aβ-induced BV2 microglial cells. In addition, RHXN, REA and RMEOH extracts significantly reduced nitric oxide (NO) level and the inhibition of NO production was correlated with the total phenolic content of the extracts. Further mechanistic studies suggested that PS root extracts attenuated the production of cytokines by regulating the phosphorylation of p38α MAPK in microglia. Importantly, PS root extracts have protective effects against Aβ-induced indirect neurotoxicity either by inhibiting the production of NO, IL-1β, IL-6, and TNF-α in BV2 cells or by protecting SHSY5Y cells against these inflammatory mediators.

    CONCLUSIONS: These findings provided evidence that PS root extracts confer neuroprotection against Aβ- induced microglial toxicity associated with the production of pro-inflammatory mediators and may be a potential therapeutic agent for inflammation-related neurological conditions including Alzheimer's disease (AD).

    Matched MeSH terms: Amyloid beta-Peptides/metabolism*
  10. Agarwal A, Durairajanayagam D, Halabi J, Peng J, Vazquez-Levin M
    Reprod Biomed Online, 2014 Jul;29(1):32-58.
    PMID: 24813754 DOI: 10.1016/j.rbmo.2014.02.013
    Oxidative stress has been established as one of the main causes of male infertility and has been implicated in many diseases associated with infertile men. It results from high concentrations of free radicals and suppressed antioxidant potential, which may alter protein expression in seminal plasma and/or spermatozoa. In recent years, proteomic analyses have been performed to characterize the protein profiles of seminal ejaculate from men with different clinical conditions, such as high oxidative stress. The aim of the present review is to summarize current findings on proteomic studies performed in men with high oxidative stress compared with those with physiological concentrations of free radicals, to better understand the aetiology of oxidative stress-induced male infertility. Each of these studies has suggested candidate biomarkers of oxidative stress, among them are DJ-1, PIP, lactotransferrin and peroxiredoxin. Changes in protein concentrations in seminal plasma samples with oxidative stress conditions were related to stress responses and to regulatory pathways, while alterations in sperm proteins were mostly associated to metabolic responses (carbohydrate metabolism) and stress responses. Future studies should include assessment of post-translational modifications in the spermatozoa as well as in seminal plasma proteomes of men diagnosed with idiopathic infertility. Oxidative stress, which occurs due to a state of imbalance between free radicals and antioxidants, has been implicated in most cases of male infertility. Cells that are in a state of oxidative stress are more likely to have altered protein expression. The aim of this review is to better understand the causes of oxidative stress-induced male infertility. To achieve this, we assessed proteomic studies performed on the seminal plasma and spermatozoa of men with high levels of oxidative stress due to various clinical conditions and compared them with men who had physiological concentrations of free radicals. A variety of sperm and seminal plasma proteins were found to be expressed either in abundance (over-expressed) or in a lesser amount (underexpressed), while other proteins were found to be unique either to men with oxidative stress or to men with a balanced ratio of antioxidants/free radicals. Each study included in this review suggested several proteins that could possibly act as biomarkers of oxidative stress-induced male infertility, such as protein DJ-1, PIP, lactotransferrin and peroxiredoxin. Pathway analysis performed in these studies revealed that the changes in seminal plasma proteins in men with oxidative stress could be attributed to stress responses and regulatory pathways, while changes in sperm proteins were linked to stress responses and metabolic responses. Subsequent studies could look into post-translational modifications in the protein profile of men with idiopathic infertility. We hope that the information in this review will contribute to a better understanding of the main causes of idiopathic male infertility.
    Matched MeSH terms: Intracellular Signaling Peptides and Proteins/metabolism
  11. Lachumanan R, Devi S, Cheong YM, Rodda SJ, Pang T
    Infect Immun, 1993 Oct;61(10):4527-31.
    PMID: 7691753
    Binding studies of 160 overlapping, synthetic octapeptides from the hydrophilic regions of the Sta58 major outer membrane protein of Rickettsia tsutsugamushi with sera from patients with scrub typhus revealed 15 immunodominant peptides which are recognized by all the sera tested. Further analysis of the specificity of peptide binding with five of these peptides indicated that the peptides showed significantly stronger binding to scrub typhus patients' sera than they did to sera from patients with other febrile illnesses common in the region, i.e., malaria, dengue fever, typhoid fever, and leptospirosis. The main antibody class binding to these peptides appears to be immunoglobulin M, and there appears to be little correlation between reactivity with peptides and antibody titers measured by the indirect immunoperoxidase test.
    Matched MeSH terms: Peptides/immunology
  12. Mudgil P, Kamal H, Priya Kilari B, Mohd Salim MAS, Gan CY, Maqsood S
    Food Chem, 2021 Aug 15;353:129374.
    PMID: 33740505 DOI: 10.1016/j.foodchem.2021.129374
    Camel milk proteins are an important substrate for bioactive peptides generation. This study investigates in-vitro antidiabetic effect (via inhibition of α-amylase (AA), α-glucosidase (AG) and dipeptidyl peptidase IV (DPP-IV)) of bovine (BC) and camel casein (CC) hydrolysates. Further, effect of simulated gastrointestinal digestion (SGID) on inhibitory potential of generated hydrolysates was also explored. Both BC and CC hydrolysates displayed potent inhibitory properties against AA (IC50 value- 0.58 & 0.59 mg/mL), AG (IC50 value- 1.04 & 0.59 mg/mL) and DPP-IV (IC50 value- 0.62 & 0.66 mg/mL), respectively. Among different peptides identified in BC and CC hydrolysates, it was observed that FLWPEYGAL was predicted to be most potent inhibitory peptide against AA. While LPTGWLM, MFE and GPAHCLL as most active inhibitor of AG and HLPGRG, QNVLPLH and PLMLP were predicted to be active against DPP-IV. Overall, BC and CC hydrolysates can be proposed to be used in different food formulations as functional antidiabetic agents.
    Matched MeSH terms: Peptides/chemistry
  13. Celikden SG, Baspinar S, Ozturk SA, Karaibrahimoglu A
    Malays J Pathol, 2020 Aug;42(2):227-236.
    PMID: 32860375
    INTRODUCTION: CIP2A is an oncoprotein involved in the progression of several human malignancies. It has recently been described as a prognostic marker in many cancers. The present study aimed to investigate the immunohistochemical expression of CIP2A in benign prostatic hyperplasia (BPH), high grade prostatic intraepithelial neoplasia (HGPIN) and prostate cancer (PC), and to analyse the association with the clinicopathological parameters in PC cases to define its role in the development and progression of PC.

    MATERIALS AND METHODS: Immunohistochemical staining for CIP2A was performed on the tissue microarray sections of 105 PC, 27 HGPIN and 27 BPH tissues. The CIP2A expression scores were compared with several clinicopathological parameters.

    RESULTS: CIP2A was expressed in 96,2% of PC, 55,6% of HGPIN and 40,7% of BPH tissues. The expression of CIP2A in PC was significantly higher than in HGPIN (p<0.0001) and BPH (p<0.0001) cases. CIP2A expression score was significantly associated with Gleason score (p=0.032) and lymphovascular invasion (p=0.039). Nevertheless, there was no statistically significant association between the expression of CIP2A and perineural invasion, pT stage, metastasis and recurrence (p>0.05). Multivariate analysis indicated that GS, lymphovascular invasion, distant metastasis were independent prognostic factors for PC patients but, CIP2A expression score was not found to be a prognostic factor. Additionally, there was no significant difference between the survival times of patients according to CIP2A expression (p=0.174).

    CONCLUSIONS: According to our results, the expression of CIP2A protein is increased in PC and its expression may be involved in the development, differentiation, and aggressiveness of PC. However, further studies are needed to confirm our findings and to clarify the role of CIP2A in the development of PC.

    Matched MeSH terms: Intracellular Signaling Peptides and Proteins/metabolism*
  14. Rosli NHM, Yahya HM, Ibrahim FW, Shahar S, Ismail IS, Azam AA, et al.
    Nutrients, 2020 Dec 12;12(12).
    PMID: 33322743 DOI: 10.3390/nu12123812
    Functional foods such as pomegranate, dates and honey were shown by various previous studies to individually have a neuroprotective effect, especially in neurodegenerative disease such as Alzheimer's disease (AD). In this novel and original study, an 1H NMR spectroscopy tool was used to identify the metabolic neuroprotective mechanism of commercially mixed functional foods (MFF) consisting of pomegranate, dates and honey, in rats injected with amyloid-beta 1-42 (Aβ-42). Forty-five male albino Wistar rats were randomly divided into five groups: NC (0.9% normal saline treatment + phosphate buffer solution (PBS) solution injection), Abeta (0.9% normal saline treatment + 0.2 µg/µL Aβ-42 injection), MFF (4 mL/kg MFF treatment + PBS solution injection), Abeta-MFF (4 mL/kg MFF treatment + 0.2 µg/µL Aβ-42 injection) and Abeta-NAC (150 mg/kg N-acetylcysteine + 0.2 µg/µL Aβ-42 injection). Based on the results, the MFF and NAC treatment improved the spatial memory and learning using Y-maze. In the metabolic analysis, a total of 12 metabolites were identified, for which levels changed significantly among the treatment groups. Systematic metabolic pathway analysis found that the MFF and NAC treatments provided a neuroprotective effect in Aβ-42 injected rats by improving the acid amino and energy metabolisms. Overall, this finding showed that MFF might serve as a potential neuroprotective functional food for the prevention of AD.
    Matched MeSH terms: Amyloid beta-Peptides/administration & dosage*
  15. Yap JKY, Pickard BS, Gan SY, Chan EWL
    Int J Biochem Cell Biol, 2021 07;136:106014.
    PMID: 34022435 DOI: 10.1016/j.biocel.2021.106014
    Alzheimer's disease is an irreversible neurodegenerative disease, which accounts for most dementia cases. Neuroinflammation is increasingly recognised for its roles in Alzheimer's disease pathogenesis which, in part, links amyloid-beta to neuronal death. Neuroinflammatory signalling can be exhibited by neurons themselves, potentially leading to widespread neuronal cell death, although neuroinflammation is commonly associated with glial cells. The presence of the inflammasomes such as nucleotide-binding leucine-rich repeat receptors protein 1 in neurons accelerates amyloid-beta -induced neuroinflammation and has been shown to trigger neuronal pyroptosis in murine Alzheimer's disease models. However, the pathways involved in amyloid-beta activation of inflammasomes have yet to be elucidated. In this study, a gene trap mutagenesis approach was utilised to resolve the genes functionally involved in inflammasome signalling within neurons, and the mechanism behind amyloid-beta-induced neuronal death. The results indicate that amyloid-beta significantly accelerated neuroinflammatory cell death in the presence of a primed inflammasome (the NLR family pyrin domain-containing 1). The mutagenesis screen discovered the atypical mitochondrial Ras homolog family member T1 as a significant contributor to amyloid-beta-induced inflammasome -mediated neuronal death. The mutagenesis screen also identified two genes involved in transforming growth factor beta signalling, namely Transforming Growth Factor Beta Receptor 1 and SNW domain containing 1. Additionally, a gene associated with cytoskeletal reorganisation, SLIT-ROBO Rho GTPase Activating Protein 3 was found to be neuroprotective. In conclusion, these genes could play important roles in inflammasome signalling in neurons, which makes them promising therapeutic targets for future drug development against neuroinflammation in Alzheimer's disease.
    Matched MeSH terms: Amyloid beta-Peptides/pharmacology*
  16. Yatim RM, Kannan TP, Ab Hamid SS
    Cell Tissue Bank, 2016 Dec;17(4):643-651.
    PMID: 27535136
    Human amniotic membrane (HAM) due to its high biocompatibility, low immunogenicity, anti-microbial, anti-viral properties as well as the presence of growth factors has been used in various clinical applications. The growth factors play an important role in wound healing. The current study aimed to explore the effect of 15 kGy gamma radiation dose on selected growth factors and receptors mRNA present in HAM. Eight growth factors, namely, EGF, HGF, KGF, TGF-α, TGF-β1, TGF-β2, TGF-β3 and bFGF and two growth factor receptors, HGFR and KGFR were evaluated in this study. The total RNA was extracted and converted to complimentary DNA using commercial kits. Subsequently, the mRNA expressions of these growth factors were evaluated using real-time PCR and the results were statistically analyzed using REST-MCS software. This study confirmed the presence of these mRNA growth factors and receptors in fresh, glycerol cryopreserved and irradiated glycerol cryopreserved HAM. In glycerol cryopreserved HAM, the results showed up-regulation of HGF and bFGF and down-regulation of EGF, HGFR, KGF, KGFR, TGF-α, TGF-β1, TGF-β2 and TGF-β3 relative to the fresh HAM which acted as the control, whereas in irradiated glycerol cryopreserved HAM, the results showed up-regulation of EGF, HGF, KGF, KGFR, TGF-β1, TGF-β2 and TGF-β3 and down-regulation of HGFR, TGF-α and bFGF relative to the glycerol cryopreserved HAM which acted as the control. However, these mRNA expressions did not show any statistical significant difference compared to the control groups. This study concluded that a dose of 15 kGy of gamma radiation did not affect the mRNA expression for the growth factors' and receptors' in the glycerol cryopreserved HAM.
    Matched MeSH terms: Intercellular Signaling Peptides and Proteins/genetics*
  17. Pan F, Lu Z, Tucker I, Hosking S, Petkov J, Lu JR
    J Colloid Interface Sci, 2016 Dec 15;484:125-134.
    PMID: 27599381 DOI: 10.1016/j.jcis.2016.08.082
    Keratins are a group of important proteins in skin and hair and as biomaterials they can provide desirable properties such as strength, biocompatibility, and moisture regaining and retaining. The aim of this work is to develop water-soluble keratin polypeptides from sheep wool and then explore how their surface adsorption behaves with and without surfactants. Successful preparation of keratin samples was demonstrated by identification of the key components from gel electrophoresis and the reproducible production of gram scale samples with and without SDS (sodium dodecylsulphate) during wool fibre dissolution. SDS micelles could reduce the formation of disulphide bonds between keratins during extraction, reducing inter-molecular crosslinking and improving keratin polypeptide solubility. However, Zeta potential measurements of the two polypeptide batches demonstrated almost identical pH dependent surface charge distributions with isoelectric points around pH 3.5, showing complete removal of SDS during purification by dialysis. In spite of different solubility from the two batches of keratin samples prepared, very similar adsorption and aggregation behavior was revealed from surface tension measurements and dynamic light scattering. Mixing of keratin polypeptides with SDS and C12TAB (dodecyltrimethylammonium bromide) led to the formation of keratin-surfactant complexes that were substantially more effective at reducing surface tension than the polypeptides alone, showing great promise in the delivery of keratin polypeptides via the surface active complexes. Neutron reflection measurements revealed the coexistence of surfactant and keratin polypeptides at the interface, thus providing the structural support to the observed surface tension changes associated with the formation of the surface active complexes.
    Matched MeSH terms: Peptides/chemistry*
  18. Syarifah-Noratiqah SB, Naina-Mohamed I, Zulfarina MS, Qodriyah HMS
    Curr Drug Targets, 2018;19(8):927-937.
    PMID: 28356027 DOI: 10.2174/1389450118666170328122527
    Neurodegenerative disease is an incurable disease which involves the degeneration or death of the nerve cells. Alzheimer's Disease (AD) is a neurodegenerative disease discovered in 1906 by Alois Alzheimer, a German clinical psychiatrist and neuroanatomist. The main pathological hallmarks of this disease are the formation of extracellular amyloid β (Aβ) plaques and intracellular neurofibrillary tangle (NFT). The accumulation of the amyloid protein aggregates in the brain of AD patients leads to oxidative stress and inflammation. Other postulated reasons for the development of this disease are cholinergic depletion and excessive glutamatergic neurotransmission. The current drugs approved and marketed for the treatment of AD are cholinesterase inhibitors (ChEIs) and N-methyl-Daspartate (NMDA) receptor antagonists. The function of ChEIs is to avoid cholinergic depletion; whereas the function of NMDA receptor antagonist is to block excessive glutamatergic neurotransmission. Unfortunately, the current drugs prescribed for AD show only modest improvement in terms of symptomatic relief and delay the progression of the disease. This review will discuss about several polyphenolic compounds as potential natural treatment options for AD. Three compounds are highlighted in this review - Curcumin (Cur), Resveratrol (Rsv) and Epigallocatechin-3- gallate (EGCG). These compounds have huge potential for AD treatment, especially due to their low frequency of adverse events. However, the current conventional pharmaceutical drugs remain as the mainstay of treatment for AD.
    Matched MeSH terms: Amyloid beta-Peptides/metabolism
  19. Magalingam KB, Radhakrishnan A, Ping NS, Haleagrahara N
    Biomed Res Int, 2018;2018:3740461.
    PMID: 29707568 DOI: 10.1155/2018/3740461
    Neurodegenerative diseases are hereditary or sporadic conditions that result in the progressive loss of the structure and function of neurons as well as neuronal death. Although a range of diseases lie under this umbrella term, Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common neurodegenerative diseases that affect a large population around the globe. Alzheimer's disease is characterized by the abnormal accumulation of extracellular amyloid-β plaques and intraneuronal neurofibrillary tangles in brain regions and manifests as a type of dementia in aged individuals that results in memory loss, multiple cognitive abnormalities, and intellectual disabilities that interfere with quality of life. Since the discovery of AD, a wealth of new information has emerged that delineates the causes, mechanisms of disease, and potential therapeutic agents, but an effective remedy to cure the diseases has not been identified yet. This could be because of the complexity of the disease process, as it involves various contributing factors that include environmental factors and genetic predispositions. This review summarizes the current understanding on neurodegenerative mechanisms that lead to the emergence of the pathology of AD.
    Matched MeSH terms: Amyloid beta-Peptides/metabolism*
  20. Huwaidi A, Pathak N, Syahir A, Ikeno S
    Biochem Biophys Res Commun, 2018 09 05;503(2):910-914.
    PMID: 29928878 DOI: 10.1016/j.bbrc.2018.06.095
    Ultraviolet (UV) radiation causes damage in all living organisms, including DNA damage that leads to cell death. Herein, we provide a new technique for UV radiation protection through intracellular short peptide expression. The late embryogenesis abundant (LEA) peptide, which functions as a shield that protects macromolecules from various abiotic stress, was obtained from the Polypedilum vanderplanki group 3 LEA protein. Recombinant Escherichia coli BL21 (DE3) expressing functional LEA short peptide in vivo were exposed to UVA and UVC radiation for 4, 6, and 8 h. E. coli transformants expressing the LEA peptide showed higher cell viability under both UVA and UVC treatment at all time points as compared with that of the control. Furthermore, the cells expressing LEA peptide showed a higher number of colony-forming units per dilution under UVA and UVC treatment. These results suggested that expression of the short peptide could be useful for the development of genetically modified organisms and in applications that require resilience of organisms to UV radiation.
    Matched MeSH terms: Peptides/genetics*
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