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D-galactose-induced liver aging model: Its underlying mechanisms and potential therapeutic interventions

Azman KF, Safdar A, Zakaria R

Exp Gerontol, 2021 07 15;150:111372.
PMID: 33905879 DOI: 10.1016/j.exger.2021.111372

Aging is associated with a variety of morphological and functional changes in the liver. Oxidative stress and inflammation are now widely accepted as the main mechanisms involved in the aging process that may subsequently cause severe injury to mitochondrial DNA which leads to apoptosis. As aging may increase the risks for various liver diseases and plays as an adverse prognostic factor increasing the mortality rate, knowledge regarding the mechanisms of age-related liver susceptibility and the possible therapeutic interventions is imperative. Due to cost and time constraints, a mimetic aging model is generally preferred to naturally aged animals to study the underlying mechanisms of aging liver. The use of D-galactose in aging research is dated back to 1962 and has since been used widely. This review aims to comprehensively summarize the effects of D-galactose-induced aging on the liver and the underlying mechanisms involved. Its potential therapeutic interventions are also discussed. It is hoped that this invaluable information may facilitate researchers in choosing the appropriate aging model and provide a valuable platform for testing potential therapeutic strategies for the prevention and treatment of age-related liver diseases.
Fulltext Tualang honey improves memory performance and decreases depressive-like behavior in rats exposed to loud noise stress

Azman KF, Zakaria R, AbdAziz C, Othman Z, Al-Rahbi B

Noise Health, 2015 Mar-Apr;17(75):83-9.
PMID: 25774610 DOI: 10.4103/1463-1741.153388

Recent evidence has exhibited dietary influence on the manifestation of different types of behavior induced by stressor tasks. The present study examined the effects of Tualang honey supplement administered with the goal of preventing or attenuating the occurrence of stress-related behaviors in male rats subjected to noise stress. Forty-eight adult male rats were randomly divided into the following four groups: i) nonstressed with vehicle, ii) nonstressed with Tualang honey, iii) stressed with vehicle, and iv) stressed with honey. The supplement was given once daily via oral gavage at 0.2 g/kg body weight. Two types of behavioral tests were performed, namely, the novel object recognition test to evaluate working memory and the forced swimming test to evaluate depressive-like behavior. Data were analyzed by a two-way analysis of variance (ANOVA) using IBM SPSS 18.0. It was observed that the rats subjected to noise stress expressed higher levels of depressive-like behavior and lower memory functions compared to the unexposed control rats. In addition, our results indicated that the supplementation regimen successfully counteracted the effects of noise stress. The forced swimming test indicated that climbing and swimming times were significantly increased and immobility times significantly decreased in honey-supplemented rats, thereby demonstrating an antidepressant-like effect. Furthermore, cognitive function was shown to be intensely affected by noise stress, but the effects were counteracted by the honey supplement. These findings suggest that subchronic exposure to noise stress induces depressive-like behavior and reduces cognitive functions, and that these effects can be attenuated by Tualang honey supplementation. This warrants further studies to examine the role of Tulang honey in mediating such effects.
Fulltext Honey as an antioxidant therapy to reduce cognitive ageing

Azman KF, Zakaria R

Iran J Basic Med Sci, 2019 Dec;22(12):1368-1377.
PMID: 32133053 DOI: 10.22038/IJBMS.2019.14027

This paper reviews the potential role of honey as a therapeutic antioxidant to reduce oxidative stress and improve cognitive ageing. All articles indexed to PubMed Central (PMC) were searched using the following key words: honey, antioxidant, memory and ageing. Honey is a natural insect-derived product with therapeutic, medicinal and nutritional values. Antioxidant properties of honey quench biologically-circulating reactive oxygen species (ROS) and counter oxidative stress while restoring the cellular antioxidant defense system. Antioxidant properties of honey may complement its nootropic effects to reduce cognitive ageing.
Fulltext Tualang Honey: A Decade of Neurological Research

Azman KF, Aziz CBA, Zakaria R, Ahmad AH, Shafin N, Ismail CAN

Molecules, 2021 Sep 06;26(17).
PMID: 34500857 DOI: 10.3390/molecules26175424

Tualang honey has been shown to protect against neurodegeneration, leading to improved memory/learning as well as mood. In addition, studies have also demonstrated its anti-inflammatory and antioxidant properties. However, a substantial part of this research lacks systematization, and there seems to be a tendency to start anew with every study. This review presents a decade of research on Tualang honey with a particular interest in the underlying mechanisms related to its effects on the central nervous system. A total of 28 original articles published between 2011 and 2020 addressing the central nervous system (CNS) effects of Tualang honey were analysed. We identified five main categories, namely nootropic, antinociceptive, stress-relieving, antidepressant, and anxiolytic effects of Tualang honey, and proposed the underlying mechanisms. The findings from this review may potentially be beneficial towards developing new therapeutic roles for Tualang honey and help in determining how best to benefit from this brain supplement.
Fulltext Electrophoretic mobility of Tween 80-encapsulated agarwood oil in aqueous

Boon, Y. T., Naim, M. N., Zakaria, R., Abu Bakar, N. F., Ahmad, N.

International Food Research Journal, 2016;23(101):133-140.
MyJurnal

A study on the feasibility of using gel electrophoresis technique in grading the agarwood oil
quality was investigated. Prior to electrophoresis, the emulsified agarwood oil droplets were
screened by a diffuse layer of ions that have equal absolute charge to that of the droplets surface
charge in aqueous phase. The condition was obtained by varying the concentrations of nonionic
surfactant; Tween 80 until the critical aggregation concentration (CAC) value of 0.0167%
(v/v) was achieved. The prepared droplets suspended in the aqueous within nano-metre size and
had ability to migrate through the agarose gel with its own specific electrophoretic mobility.
However, due to the limitation of gel pore size, only large oil droplets (>200 nm) indicated
visible bands. Overall, a novel work for grading the emulsified agarwood oil droplet with its
own electrical properties was feasible.
Fulltext Coping Strategies for Sexual Problems and Sexual Dysfunction Amongst Malay Women With Breast Cancer. A Qualitative Study

Che Ya SN, Muhamad R, Mohd Zain N, Zakaria R, Ishak A, Hassan II, et al.

Sex Med, 2021 Jun;9(3):100336.
PMID: 33794448 DOI: 10.1016/j.esxm.2021.100336

INTRODUCTION: Women' sexuality becomes complex after breast cancer diagnosis and sexual health is highly neglected in the management of the illness.
AIMS: To explore the coping and strategies to overcome sexuality problems and sexual dysfunction among women with breast cancer.
MATERIAL AND METHODS: Using the in-depth and photo-elicitation interview methods, this qualitative study following phenomenological analysis was conducted on fourteen married female respondents with breast cancer and had the positive result for female sexual dysfunction (FSD) screened by Female Sexual Function Index (FSFI-6 items) from Kelantan, Malaysia. The interviews data were audio-recorded, transcribed verbatim and managed in analytic computer software NVivo11 Pro. The transcriptions were analyzed using thematic analysis by referring to the meaning-making theory.
MAIN OUTCOME MEASURES: We identified overlapping themes of coping and strategies among women with breast cancer to overcome sexual problems and sexual dysfunction which correspond with meaning-making theory.
RESULTS: Three themes have emerged. Women with breast cancer that developed sexuality problem and sexual dysfunction strived to accept the illness using religious belief and conform by altering sexual practices. These individuals positively look for a solution by seeking formal healthcare advice, modify their physical appearance, active discussion with the husband and support from other survivors. A few of them passively struggle with the subject by averting the intimacy and receptive toward polygamy.
CONCLUSION: This study highlighted the various mechanisms that emphasized the pivotal role of religious belief and relationship context as key factors in the coping strategies among women with breast cancer in Malaysia. The finding may not be generalized to other countries. Che Ya SN, Muhamad R, Zain NM, et al. Coping Strategies for Sexual Problems and Sexual Dysfunction Amongst Malay Women With Breast Cancer. A Qualitative Study. Sex Med 2021;9:100336.
"I Lost My Gift to Him": The Consequences of Female Sexual Dysfunction on Breast Cancer Survivors in Malaysia

Che Ya SN, Muhamad R, Zakaria R, Mohd Zain N, Ishak A, Hassan II, et al.

Arch Sex Behav, 2021 Nov 08.
PMID: 34750771 DOI: 10.1007/s10508-021-02051-3

Sexuality is currently neglected in the medical care of cancer patients although female sexual dysfunction (FSD) and sexual problems are highly prevalent among breast cancer patients in Malaysia. This paper explores the consequences of breast cancer and its treatment on the sexuality and sexual health of women with breast cancer using a qualitative design and a phenomenological methodology. Fourteen married women with breast cancer who fulfill the criteria for FSD from Kelantan, Malaysia participated in two interviews: in-depth interview and followed by photo-elicitation interview after two weeks duration. The interviews were audio-recorded, transcribed verbatim, and analyzed using thematic analysis. We identified overlapping themes that can be explained by sexual script theory. Breast cancer treatments disturb the sex response cycle, leading to changes in sexuality, from intimacy in marriage to women preferring physical affection to intercourse. The women struggled with a perceived imperfection about symbol of femininity after noticing changes in their husbands' sexual performance and after experiencing their own sentiments of inadequacy as a wife. Fear and guilt surfaced as part of the journey, accompanied by frustration on the part of the spouse, or him becoming more attentive. This study highlights the problem of breast cancer and its treatment as regards the sexual well-being of patients and their spouses. Hence, recognizing and addressing sexual health will improve the overall experience for survivors.
Note: Fabrication of tapered fibre tip using mechanical polishing method

Cheong YK, Lim KS, Lim WH, Chong WY, Zakaria R, Ahmad H

Rev Sci Instrum, 2011 Aug;82(8):086115.
PMID: 21895293 DOI: 10.1063/1.3627374

Tapered fibre tips fabricated using mechanical polishing method is studied. The fibre tips are formed by sequential polishing flat-ended single mode fibres with decreasing aluminium oxide polishing film grit size. Based on the proposed technique, tapered fibre tips with cone angle ranging from 30° to 130° are fabricated by controlling the polishing angle. Besides the variety of cone angle, considerable smoothness of the fibre tip surface may assist in good metal coating and hence a well-defined aperture can be obtained. In addition, this paper presents a two-step hybrid fabrication method combining the proposed polishing method with chemical etching method to increase the possible fibre tip cone angles achievable by chemical etching method.
Short report: differences in dihydrofolate reductase but not dihydropteroate synthase alleles in Plasmodium falciparum isolates from geographically distinct areas in Malaysia

Cox-Singh J, Zakaria R, Abdullah MS, Rahman HA, Nagappan S, Singh B

Am J Trop Med Hyg, 2001 6 27;64(1-2):28-31.
PMID: 11425158

Dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) alleles were typed in 67 Malaysian Plasmodium falciparum isolates. The isolates were collected from two geographically distinct locations: 51 from Sabah, Malaysian Borneo, where sulfadoxine/pyrimethamine (SDX/PYR) is used to treat uncomplicated malaria and 16 from Peninsular Malaysia where in vivo resistance to SDX/PYR has been reported. A total of seven dhps alleles were identified with no significant difference in allele frequency between the 2 populations. Two of the dhps alleles described here have not been previously reported. Four dhfr alleles were detected in 67 P. falciparum isolates. Eighty-seven percent of the isolates from the Peninsula, where clinical SDX/PYR failure has been reported, had dhfr alleles with triple point mutations while all of the isolates from Sabah had dhfr alleles with 2 or less point mutations. The difference in dhfr allele frequency between the two populations was highly significant. There was no correlation between in vitro PYR response and accumulation of dhfr point mutations.
Simple blood-spot sampling with nested polymerase chain reaction detection for epidemiology studies on Brugia malayi

Cox-Singh J, Pomrehn AS, Rahman HA, Zakaria R, Miller AO, Singh B

Int J Parasitol, 1999 May;29(5):717-21.
PMID: 10404266

In the absence of a suitable Brugia malayi antigen detection assay, PCR remains one of the more sensitive alternatives to Giemsa-stained thick blood films for B. malayi detection. The need for refrigerated storage and transportation of blood has limited the use of PCR for large-scale epidemiology studies in remote endemic areas. Here we report simple finger-prick blood-spot collection, a one-tube DNA template extraction method and the development of a B. malayi-specific nested PCR assay. The assay was tested on 145 field samples and was positive for all 30 microscopy-positive samples and for an additional 13 samples which were microscopy-negative.
Fulltext Determining the Effect of Centrifugal Force on the Desired Growth and Properties of PCPDTBT as p-Type Nanowires

Doris M, Aziz F, Alhummiany H, Bawazeer T, Alsenany N, Mahmoud A, et al.

Nanoscale Res Lett, 2017 Dec;12(1):67.
PMID: 28116608 DOI: 10.1186/s11671-017-1851-0

In this study, low-bandgap polymer poly{[4,4-bis(2-ethylhexyl)-cyclopenta-(2,1-b;3,4-b')dithiophen]-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl} (PCPDTBT) nanostructures have been synthesized via a hard nanoporous alumina template of centrifugal process. Centrifuge has been used to infiltrate the PCPDTBT solution into the nanoporous alumina by varying the rotational speeds. The rotational speed of centrifuge is directly proportional to the infiltration force that penetrates into the nanochannels of the template. By varying the rotational speed of centrifuge, different types of PCPDTBT nanostructures are procured. Infiltration force created during the centrifugal process has been found a dominant factor in tuning the morphological, optical, and structural properties of PCPDTBT nanostructures. The field emission scanning electron microscopy (FESEM) images proved the formation of nanotubes and nanowires. The energy-dispersive X-ray spectroscope (EDX) analysis showed that the nanostructures were composed of PCPDTBT with complete dissolution of the template.
Fulltext Potential of Zeolite and Algae in Biomass Immobilization

Emami Moghaddam SA, Harun R, Mokhtar MN, Zakaria R

Biomed Res Int, 2018;2018:6563196.
PMID: 30643814 DOI: 10.1155/2018/6563196

The interest in utilizing algae for wastewater treatment has been increased due to many advantages. Algae-wastewater treatment system offers a cost-efficient and environmentally friendly alternative to conventional treatment processes such as electrocoagulation and flocculation. In this biosystem, algae can assimilate nutrients in the wastewater for their growth and simultaneously capture the carbon dioxide from the atmosphere during photosynthesis resulting in a decrease in the greenhouse gaseousness. Furthermore, the algal biomass obtained from the treatment process could be further converted to produce high value-added products. However, the recovery of free suspended algae from the treated effluent is one of the most important challenges during the treatment process as the current methods such as centrifugation and filtration are faced with the high cost. Immobilization of algae is a suitable approach to overcome the harvesting issue. However, there are some drawbacks with the common immobilization carriers such as alginate and polyacrylamide related to low stability and toxicity, respectively. Hence, it is necessary to apply a new carrier without the mentioned problems. One of the carriers that can be a suitable candidate for the immobilization is zeolite. To date, various types of zeolite have been used for the immobilization of cells of bacteria and yeast. If there is any possibility to apply them for the immobilization of algae, it needs to be considered in further studies. This article reviews cell immobilization technique, biomass immobilization onto zeolites, and algal immobilization with their applications. Furthermore, the potential application of zeolite as an ideal carrier for algal immobilization has been discussed.
Stability improvement of algal-alginate beads by zeolite molecular sieves 13X

Emami Moghaddam SA, Harun R, Mokhtar MN, Zakaria R

Int J Biol Macromol, 2019 Jul 01;132:592-599.
PMID: 30922914 DOI: 10.1016/j.ijbiomac.2019.03.191

This research aimed to improve the stability of Chlorella-Alginate Beads (CABs) by zeolite molecular sieves 13X. Dissolution time of synthesized Zeolite-Algal-Alginate Beads (ZABs) in a chelating agent revealed a significant improvement on the beads stability (78.5 ± 0.5 min) compared to the control beads (51.5 ± 0.5 min) under the optimum conditions of zeolite/alginate (1.5:1), pH 5 and 2% of beads. Monitoring cell growth during 5 days of incubation showed good biocompatibility of zeolite 13X. Scanning electron microscopy (SEM) indicated rough surface and spherical shapes of ZABs. Energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) of ZABs confirmed the presence of zeolite 13X within the matrix. The zeta potential value of ZABs indicated that the beads were relatively stable. The findings of this research showed that zeolite molecular sieves 13X have the potential to improve the stability of algal-alginate beads compared to common beads.
Fulltext Cryptic coloration of Macaranga bancana seedlings: A unique strategy for a pioneer species

Fadzly N, Zuharah WF, Mansor A, Zakaria R

Plant Signal Behav, 2016 07 02;11(7):e1197466.
PMID: 27315145 DOI: 10.1080/15592324.2016.1197466

Macaranga bancana is considered as a successful pioneer plant species. Usually found in disturbed and open areas, most of the current research focused on its relations with ants. One of the unique feature of the plants is that the seedling leaves are red, resembling and almost matching the background. Using a portable spectrometer, we measured the color reflectance of M. bancana seedlings (less than 20 cm in height). We also measured the leaf litter reflectance, adult M. bancana leaves and also seedlings of several other species found in the vicinity of M. bancana seedlings. The reflectances of M. bancana seedlings are very similar to that of the leaf litter background. We suggest that this cryptic coloration is crucial during the early stages of the plant when it still cannot rely on the protection of ants.
In Vitro Efficacy of Aqueous and Methanol Extract of Cassia siamea Against the Motility of Caenorhabditis elegans

Gagman HA, Him NAIIN, Ahmad H, Sulaiman SF, Zakaria R, Termizi FHM

Trop Life Sci Res, 2020 Oct;31(3):145-159.
PMID: 33214861 DOI: 10.21315/tlsr2020.31.3.10

Gastrointestinal nematode infections can cause great losses in revenue due to decrease livestock production and animal death. The use of anthelmintic to control gastrointestinal nematode put a selection pressure on nematode populations which led to emergence of anthelmintic resistance. Because of that, this study was carried out to investigate the efficacy of aqueous and methanol extract of Cassia siamea against the motility of C. elegans Bristol N2 and C. elegans DA1316. Caenorhabditis elegans Bristol N2 is a susceptible strain and C. elegans DA1316 is an ivermectin resistant strain. In vitro bioassay of various concentrations of (0.2, 0.6, 0.8, 1.0 and 2.0 mg mL-1) aqueous and methanol extracts of C. siamea was conducted against the motility of L4 larvae of C. elegans Bristol N2 and C. elegans DA1316. The L4 larvae were treated with 0.02 μg mL-1 of ivermectin served as positive control while those in M9 solution served as negative control. The activity of the extracts was observed after 24 h and 48 h. A significant difference was recorded in the extract performance compared to control at (P < 0.001) after 48 h against the motility of the larvae of both strains. The methanol extracts inhibited the motility of C. elegans Bristol N2 by 86.7% as well as DA1316 up to 84.9% at 2.0 mg mL-1 after 48 h. The methanol extract was more efficient than aqueous extract (P < 0.05) against the motility of both strains of C. elegans. Cassia siamea may be used as a natural source of lead compounds for the development of alternative anthelmintic against parasitic nematodes as well ivermectin resistant strains of nematodes.
Fulltext Design and evaluation of a recombinant multi-epitope antigen for serodiagnosis of Toxoplasma gondii infection in humans

Hajissa K, Zakaria R, Suppian R, Mohamed Z

Parasit Vectors, 2015;8:315.
PMID: 26062975 DOI: 10.1186/s13071-015-0932-0

Serological investigation remains the primary approach to achieve satisfactory results in Toxoplasma gondii identification. However, the accuracy of the native antigen used in the current diagnostic kits has proven to be insufficient as well as difficult to standardize, so significant efforts have been made to find alternative reagents as capture antigens. Consequently, multi-epitope peptides are promising diagnostic markers, with the potential for improving the accuracy of diagnostic kits. In this study, we described a simple, inexpensive and improved strategy to acquire such diagnostic markers. The study was aimed at producing novel synthetic protein consisting of multiple immunodominant epitopes of several T. gondii antigens.
Epitope-based vaccine as a universal vaccination strategy against Toxoplasma gondii infection: A mini-review

Hajissa K, Zakaria R, Suppian R, Mohamed Z

J Adv Vet Anim Res, 2019 Jun;6(2):174-182.
PMID: 31453188 DOI: 10.5455/javar.2019.f329

Despite the significant progress in the recent efforts toward developing an effective vaccine against toxoplasmosis, the search for new protective vaccination strategy still remains a challenge and elusive goal because it becomes the appropriate way to prevent the disease. Various experimental approaches in the past few years showed that developing a potential vaccine against the disease can be achievable. The combination of multi-epitopes expressing different stages of the parasite life cycle has become an optimal strategy for acquiring a potent, safe, and effective vaccine. Epitope-based vaccines have gained attention as alternative vaccine candidates due to their ability of inducing protective immune responses. This mini-review highlights the current status and the prospects of Toxoplasma gondii vaccine development along with the application of epitope-based vaccine in the future parasite immunization as a novel under development and evaluation strategy.
Immunogenicity of Multiepitope Vaccine Candidate against Toxoplasma gondii Infection in BALB/c Mice

Hajissa K, Zakaria R, Suppian R, Mohamed Z

Iran J Parasitol, 2018 8 3;13(2):215-224.
PMID: 30069205

Background: Toxoplasma gondii is a widely prevalent intracellular protozoan parasite which causes serious clinical and veterinary problems. Development of an effective vaccine for controlling toxoplasmosis is an extremely important aim. In the present study, the protective efficacy of recombinant multiepitope antigen (USM.TOXO1) expressing nine potential epitopes identified from SAG1, GRA2, and GRA7 of Toxoplasma gondii was evaluated in BALB/c mice.
Methods: Mice were immunized subcutaneously with three doses of USM.TOXO1 antigen (10 μg/ml). Following the immunization, the IgG antibody, IgG subclass, IFN-γ and IL-4 production were evaluated using ELISA, the study was conducted at Animal Research and Service Center (ARASC), USM Health Campus in 2016.
Results: Mice immunized with USM.TOXO1 significantly induced a mixed Th1/Th2 response polarized toward the IgG1 antibody isotype. While the cytokine analysis revealed a significant release of IFN-γ cytokines.
Conclusion: USM.TOXO1 is a potential vaccine candidate that elicits strong immunity in BALB/c mice. The proven immunogenicity of the generated antigen can serve as a premise for further use of epitope-based vaccine in the immunoprevention of human and animal toxoplasmosis.
Fulltext An evaluation of a recombinant multiepitope based antigen for detection of Toxoplasma gondii specific antibodies

Hajissa K, Zakaria R, Suppian R, Mohamed Z

BMC Infect Dis, 2017 12 29;17(1):807.
PMID: 29284420 DOI: 10.1186/s12879-017-2920-9

BACKGROUND: The inefficiency of the current tachyzoite antigen-based serological assays for the serodiagnosis of Toxoplasma gondii infection mandates the need for acquirement of reliable and standard diagnostic reagents. Recently, epitope-based antigens have emerged as an alternative diagnostic marker for the achievement of highly sensitive and specific capture antigens. In this study, the diagnostic utility of a recombinant multiepitope antigen (USM.TOXO1) for the serodiagnosis of human toxoplasmosis was evaluated.
METHODS: An indirect enzyme-linked immunosorbent assay (ELISA) was developed to evaluate the usefulness of USM.TOXO1 antigen for the detection of IgG antibodies against Toxoplasma gondii in human sera. Whereas the reactivity of the developed antigen against IgM antibody was evaluated by western blot and Dot enzyme immunoassay (dot-EIA) analysis.
RESULTS: The diagnostic performance of the new antigens in IgG ELISA was achieved at the maximum values of 85.43% and 81.25% for diagnostic sensitivity and specificity respectively. The USM.TOXO1 was also proven to be reactive with anti- T. gondii IgM antibody.
CONCLUSIONS: This finding makes the USM.TOXO1 antigen an attractive candidate for improving the toxoplasmosis serodiagnosis and demonstrates that multiepitope antigens could be a potential and promising diagnostic marker for the development of high sensitive and accurate assays.
Exogenous leptin administration decreases sperm count and increases the fraction of abnormal sperm in adult rats

Haron MN, D'Souza UJ, Jaafar H, Zakaria R, Singh HJ

Fertil Steril, 2010 Jan;93(1):322-4.
PMID: 19709655 DOI: 10.1016/j.fertnstert.2009.07.995

Daily intraperitoneal injection of 5-30 microg/kg body weight of leptin for 42 days to adult rats decreases sperm count and increases the fraction of abnormal sperm.

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