Displaying publications 1 - 20 of 60 in total

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  1. Fahim A, Himratul-Aznita WH, Abdul-Rahman PS
    Pak J Med Sci, 2020 2 18;36(2):271-275.
    PMID: 32063973 DOI: 10.12669/pjms.36.2.1457
    Objective: Chlorhexidine mouthrinses are considered a gold standard as an adjunct treatment of oral infections. However, owing to its toxicity, discoloration of tooth surface and the emerging prevalence of drug-resistant species, attention is being given to exploring natural alternatives to the drug.

    Methods: The experiment was carried out in Azra Naheed Center for Research and Development (ANCRD), Superior University, Lahore, Pakistan from September 2018 till May 2019. Biofilms and planktonic cells of C. albicans alone and in combination with streptococci were subjected to chlorhexidine, allium sativum and bakuchiol individually and to allium-bakuchiol combination. Kirby-Bauer test, antifungal susceptibility testing, CFU count and drug synergy assessment was done on planktonic cells. Dynamic biofilms were formed to mimic conditions similar to oral cavity and CFU was determined.

    Results: MIC of all three agents was higher against mixed species when compared to single species planktonic cells and biofilm. Allium sativum and bakuchiol demonstrated synergistic effects. The decrease in CFU count and minimum biofilm reduction to salivary pellicle caused by allium sativum-bakuchiol was comparable to that of chlorhexidine.

    Conclusion: Thus, allium sativum-bakuchiol combination demonstrated antimicrobial effects similar to chlorhexidine against planktonic cells and dynamic biofilm. It could serve as a possible natural, economical alternative to chlorhexidine mouthrinses usually recommended in dental clinics. However, in vivo studies are required to determine the correct dosage of these agents.

  2. Fahim A, Himratul-Aznita WH, Abdul-Rahman PS, Alam MK
    PeerJ, 2022;9:e12251.
    PMID: 35036111 DOI: 10.7717/peerj.12251
    Background: Polymicrobial biofilms are notorious for causing intraoral tissue destruction. Streptococcus sanguinis and Streptococcus mitis, commensals of oral cavities, have been found co-existing with C. albicans in resistant oral infections. There is an urgent need to find alternative treatment options. This study aims to assess the efficacy of garlic (G) and bakuchiol (Bk) combination against candida virulent genes and their subsequently secreted proteins.

    Methods: In vitro single species biofilms of C. albicans, and mixed species biofilms formed in combination with streptococci were exposed to bakuchiol and garlic extract (Bk+G). Gene expression of agglutinin-like sequence (ALS1), (ALS3), adhesin-like wall proteins (HWP1) and aspartyl proteinases (SAP5) were determined using qPCR and their subsequent proteins were assessed through Western blotting.

    Results: Virulent genes were significantly downregulated in single species biofilms when they were treated with Bk+G combination. However, Bk+G did not have significant effect on ALS1 and HWP1 gene in polymicrobial biofilms. ALS3 and SAP5 were significantly downregulated in Bk+G treated polymicrobial biofilm. Similar results were portrayed in Western blotting.

    Conclusion: Bk+G combination exhibited antimicrobial effects against single and mixed species biofilms. The findings might provide insights for treating resistant candida infections. This combination could potentially serve as an herbal alternative to traditional antifungals following further research.

  3. Harun WHAW, Zulaila CON, Fahim A, Allah NUM
    J Taibah Univ Med Sci, 2023 Oct;18(5):967-975.
    PMID: 36866244 DOI: 10.1016/j.jtumed.2023.02.004
    OBJECTIVES: Dimorphic transformation from yeast cells to hyphae is considered one of the major virulence factors of candidal species. The development of antifungal resistance against several candida diseases has led researchers to find plant derived alternatives. We aimed to determine the effect of hydroxychavicol (HC), Amphotericin B (AMB), and their combination (HC + AMB) on the transition and germination of oral Candida species.

    METHODS: The antifungal susceptibility of hydroxychavicol (HC) and Amphotericin B (AMB) separately and in a mixture (HC + AMB) against Candida albicans ATCC 14053, Candida parapsilosis ATCC 22019, Candida tropicalis ATCC 13803, and Candida dubliniensis ATCC MYA-2975 was determined by broth microdilution technique. Minimal Inhibitory Concentration was calculated based on the CLSI protocols. The MIC50, fractional inhibitory concentration (FIC) index, and IC50 were also determined. The IC50 values were used as the treatment concentration of HC, AMB, and HC + AMB to study the effect of antifungal inhibition on yeast hypha transition (gemination). The germ tube formation percentage of candida species was calculated at several intervals using a colorimetric assay.

    RESULTS: The MIC50 range of HC alone against Candida species was between 120-240 µg per mL while that of AMB was between 2-8 µg per mL, respectively. The combination of HC + AMB at 1:1 and 2:1 demonstrated the strongest synergistic activity against C. albicans with an FIC index of 0.07. Moreover, within the first hour of treatment, the total percentage of germinating cells was significantly reduced by 79% (p < 0.05).

    CONCLUSION: The combination of HC + AMB displayed synergism and inhibited C. albicans hyphal growth. HC + AMB combination slowed the germination process and exhibited consistent prolonged effect up to 3 h post-treatment. The results of this study will pave the way for potential in vivo studies.

  4. Fahim A, Mahmood R, Haider I, Luqman M, Ikhlaq I, Mahmood T, et al.
    PeerJ, 2022;10:e14152.
    PMID: 36213513 DOI: 10.7717/peerj.14152
    OBJECTIVE: The perceived oral health refers to the very own perception of a person's oral health (OH). This study aims to explore the association of perceived oral health status (PSR-OHS) with clinically determined OHS in three age groups: young adults, adults and older adults. This study also aims to identify demographic, socio-economic and/or clinical factors that influence PSR-OHS.

    METHODS: A cross-sectional study was conducted in ten different dental hospitals of Pakistan. The one-way ANOVA test was used to analyze patient's demographic distribution with PSR-OHS and oral functions. The complex sample general linear model was used to determine association between clinical OH and PSR-OHS. Analyses of each age group were conducted separately.

    RESULTS: A total of 1,804 outdoor patients participated in the study, out of which 660 were young adults, 685 adults and 459 were older adults. Overall self-perception of all age groups about their oral health was 'good' (mean = 3.71). Female gender and education status were a significant factor in young adults and adults. Family income affected PSR-OHS of only the adult age group. Frequent visit to dental clinic and preventive reason of dental attendance were associated with good PSR-OHS. DMFT score, prosthesis score and periodontal score also affected the PSR-OHS of individuals. Association between PSR-OHS and clinical examination was confirmed by complex general linear model.

    CONCLUSION: There are differences in the perceived oral health status of young adults, adults and older adults. The variables, age, education, family income, DMFT score, prosthesis score and periodontal score directly influence the self-perception of individuals.

  5. Alam MK, Alfawzan AA, Abutayyem H, Kanwal B, Alswairki HJ, Verma S, et al.
    Sci Prog, 2023;106(1):368504231156297.
    PMID: 36803068 DOI: 10.1177/00368504231156297
    The purpose of this meta-analysis was to strengthen the credibility of primary research results by combining open-source scientific material, namely a comparison of craniofacial features (Cfc) between Crouzon's syndrome (CS) patients and non-CS populations. All articles published up to October 7, 2021, were included in the search of PubMed, Google Scholar, Scopus, Medline, and Web of Science. The PRISMA guidelines were followed to conduct this study. PECO framework was applied in the following ways: Those who have CS are denoted by the letter P, those who have been diagnosed with CS via clinical or genetic means by the letter E, those who do not have CS by the letter C, and those who have a Cfc of CS by the letter O. Independent reviewers collected the data and ranked the publications based on their adherence to the Newcastle-Ottawa Quality Assessment Scale. A total of six case-control studies were reviewed for this meta-analysis. Due to the large variation in cephalometric measures, only those published in at least two previous studies were included. This analysis found that CS patients had a smaller skull and mandible volumes than those without CS.in terms of SNA° (MD = -2.33, p = <0.001, I2 = 83.6%) and ANB°(MD = -1.89, p = <0.005, I2 = 93.1%)), as well as ANS (MD = -1.87, p = 0.001, I2 = 96.5%)) and SN/PP (MD = -1.99, p = 0.036, I2 = 77.3%)). In comparison to the general population, people with CS tend to have shorter and flatter cranial bases, smaller orbital volumes, and cleft palates. They differ from the general population in having a shorter skull base and more V-shaped maxillary arches.
  6. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Feb 13;114(6):061801.
    PMID: 25723204
    A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8  TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7  fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2  cm, excluding masses below 790 GeV at 95% confidence level.
  7. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Feb 6;114(5):051801.
    PMID: 25699433
    A study of vector boson scattering in pp collisions at a center-of-mass energy of 8 TeV is presented. The data sample corresponds to an integrated luminosity of 19.4  fb(-1) collected with the CMS detector. Candidate events are selected with exactly two leptons of the same charge, two jets with large rapidity separation and high dijet mass, and moderate missing transverse energy. The signal region is expected to be dominated by electroweak same-sign W-boson pair production. The observation agrees with the standard model prediction. The observed significance is 2.0 standard deviations, where a significance of 3.1 standard deviations is expected based on the standard model. Cross section measurements for W(±)W(±) and WZ processes in the fiducial region are reported. Bounds on the structure of quartic vector-boson interactions are given in the framework of dimension-eight effective field theory operators, as well as limits on the production of doubly charged Higgs bosons.
  8. Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Phys Rev Lett, 2014 Apr 25;112(16):161802.
    PMID: 24815637
    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7  fb-1 of proton-proton collision data at s=8  TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.
  9. CMS Collaboration, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.
    Eur Phys J C Part Fields, 2014 09 26;74(9):3036.
    PMID: 25814912
    Searches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and [Formula: see text], [Formula: see text], and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy [Formula: see text] with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5 [Formula: see text]. The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to 720 [Formula: see text], and sleptons up to 260 [Formula: see text], depending on the model details.
  10. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2014 10 15;74(10):3076.
    PMID: 25814871
    Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1[Formula: see text]at [Formula: see text] and 19.7[Formula: see text]at 8[Formula: see text] . A clear signal is observed in the diphoton channel at a mass close to 125[Formula: see text] with a local significance of [Formula: see text], where a significance of [Formula: see text] is expected for the standard model Higgs boson. The mass is measured to be [Formula: see text] , and the best-fit signal strength relative to the standard model prediction is [Formula: see text][Formula: see text][Formula: see text]. Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.
  11. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Feb 19;116(7):071801.
    PMID: 26943527 DOI: 10.1103/PhysRevLett.116.071801
    A search for narrow resonances in proton-proton collisions at sqrt[s]=13  TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4  fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.
  12. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Jan 22;116(3):032301.
    PMID: 26849587 DOI: 10.1103/PhysRevLett.116.032301
    The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02  TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6  nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60  GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.
  13. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2015 Mar 13;114(10):101801.
    PMID: 25815923
    Results are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7  fb^{-1} of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations from the standard model predictions are observed and lower limits are set on the masses of new invisible bosons. In particular, scalar and vector particles, with masses below 330 and 650 GeV, respectively, are excluded at 95% confidence level, thereby substantially extending a previous limit published by the CDF Collaboration.
  14. Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.
    Phys Rev Lett, 2017 Apr 21;118(16):162301.
    PMID: 28474955 DOI: 10.1103/PhysRevLett.118.162301
    The relative modification of the prompt ψ(2S) and J/ψ yields from pp to PbPb collisions, at the center-of-mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0  pb^{-1} and 464  μb^{-1}, respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs, (N_{ψ(2S)}/N_{J/ψ})_{PbPb}/(N_{ψ(2S)}/N_{J/ψ})_{pp}, is determined as a function of PbPb collision centrality and charmonium transverse momentum p_{T}, in two kinematic intervals: |y|<1.6 covering 6.5
  15. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2017 Mar 24;118(12):122301.
    PMID: 28388204 DOI: 10.1103/PhysRevLett.118.122301
    Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p-Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range |η|<2.4, and a third particle measured in the hadron forward calorimeters (4.4
  16. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2017;77(11):751.
    PMID: 31999282 DOI: 10.1140/epjc/s10052-017-5140-y
    Measurements of the associated production of a
    Z
    boson with at least one jet originating from a b quark in proton-proton collisions at


    s

    =
    8

    TeV

    are presented. Differential cross sections are measured with data collected by the CMS experiment corresponding to an integrated luminosity of 19.8



    fb

    -
    1



    .
    Z
    bosons are reconstructed through their decays to electrons and muons. Cross sections are measured as a function of observables characterizing the kinematics of the
    b
    jet and the
    Z
    boson. Ratios of differential cross sections for the associated production with at least one
    b
    jet to the associated production with any jet are also presented. The production of a
    Z
    boson with at least two
    b
    jets is investigated, and differential cross sections are measured for the dijet system. Results are compared to theoretical predictions, testing two different flavour schemes for the choice of initial-state partons.
  17. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(7):371.
    PMID: 28280444 DOI: 10.1140/epjc/s10052-016-4206-6
    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons ([Formula: see text]) in proton-proton collisions collected by the CMS experiment at the LHC at [Formula: see text]. The data correspond to an integrated luminosity of 19.7[Formula: see text]. The search considers [Formula: see text] resonances with masses between 1 and 3[Formula: see text], having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and [Formula: see text] events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 % confidence level for the product of the production cross section and branching fraction [Formula: see text] range from 10 to 1.5[Formula: see text] for the mass of X from 1.15 to 2.0[Formula: see text], significantly extending previous searches. For a warped extra dimension theory with a mass scale [Formula: see text] [Formula: see text], the data exclude radion scalar masses between 1.15 and 1.55[Formula: see text].
  18. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(7):372.
    PMID: 28280445 DOI: 10.1140/epjc/s10052-016-4205-7
    Inclusive jet production in pPb collisions at a nucleon-nucleon (NN) center-of-mass energy of [Formula: see text] is studied with the CMS detector at the LHC. A data sample corresponding to an integrated luminosity of 30.1 nb[Formula: see text] is analyzed. The jet transverse momentum spectra are studied in seven pseudorapidity intervals covering the range [Formula: see text] in the NN center-of-mass frame. The jet production yields at forward and backward pseudorapidity are compared and no significant asymmetry about [Formula: see text] is observed in the measured kinematic range. The measurements in the pPb system are compared to reference jet spectra obtained by extrapolation from previous measurements in pp collisions at [Formula: see text]. In all pseudorapidity ranges, nuclear modifications in inclusive jet production are found to be small, as predicted by next-to-leading order perturbative QCD calculations that incorporate nuclear effects in the parton distribution functions.
  19. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 06 09;75(6):251.
    PMID: 26097407
    A search for a standard model Higgs boson produced in association with a top-quark pair and decaying to bottom quarks is presented. Events with hadronic jets and one or two oppositely charged leptons are selected from a data sample corresponding to an integrated luminosity of 19.5[Formula: see text] collected by the CMS experiment at the LHC in [Formula: see text] collisions at a centre-of-mass energy of 8[Formula: see text]. In order to separate the signal from the larger [Formula: see text]  + jets background, this analysis uses a matrix element method that assigns a probability density value to each reconstructed event under signal or background hypotheses. The ratio between the two values is used in a maximum likelihood fit to extract the signal yield. The results are presented in terms of the measured signal strength modifier, [Formula: see text], relative to the standard model prediction for a Higgs boson mass of 125[Formula: see text]. The observed (expected) exclusion limit at a 95 % confidence level is [Formula: see text] (3.3), corresponding to a best fit value [Formula: see text].
  20. Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 05 14;75(5):212.
    PMID: 25999783
    Properties of the Higgs boson with mass near 125[Formula: see text] are measured in proton-proton collisions with the CMS experiment at the LHC. Comprehensive sets of production and decay measurements are combined. The decay channels include [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] pairs. The data samples were collected in 2011 and 2012 and correspond to integrated luminosities of up to 5.1[Formula: see text] at 7[Formula: see text] and up to 19.7[Formula: see text] at 8[Formula: see text]. From the high-resolution [Formula: see text] and [Formula: see text] channels, the mass of the Higgs boson is determined to be [Formula: see text]. For this mass value, the event yields obtained in the different analyses tagging specific decay channels and production mechanisms are consistent with those expected for the standard model Higgs boson. The combined best-fit signal relative to the standard model expectation is [Formula: see text] at the measured mass. The couplings of the Higgs boson are probed for deviations in magnitude from the standard model predictions in multiple ways, including searches for invisible and undetected decays. No significant deviations are found.
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