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  1. Article ; Online: Conversion of spikers to bursters in pituitary cell networks: Is it better to disperse for maximum exposure or circle the wagons?

    Fazli, Mehran / Bertram, Richard

    PLoS computational biology

    2024  Volume 20, Issue 1, Page(s) e1011811

    Abstract: The endocrine cells of the pituitary gland are electrically active, and in vivo they form small networks where the bidirectional cell-cell coupling is through gap junctions. Numerous studies of dispersed pituitary cells have shown that typical behaviors ... ...

    Abstract The endocrine cells of the pituitary gland are electrically active, and in vivo they form small networks where the bidirectional cell-cell coupling is through gap junctions. Numerous studies of dispersed pituitary cells have shown that typical behaviors are tonic spiking and bursting, the latter being more effective at evoking secretion. In this article, we use mathematical modeling to examine the dynamics of small networks of spiking and bursting pituitary cells. We demonstrate that intrinsic bursting cells are capable of converting intrinsic spikers into bursters, and perform a fast/slow analysis to show why this occurs. We then demonstrate the sensitivity of network dynamics to the placement of bursting cells within the network, and demonstrate strategies that are most effective at maximizing secretion from the population of cells. This study provides insights into the in vivo behavior of cells such as the stress-hormone-secreting pituitary corticotrophs that are switched from spiking to bursting by hypothalamic neurohormones. While much is known about the electrical properties of these cells when isolated from the pituitary, how they behave when part of an electrically coupled network has been largely unstudied.
    MeSH term(s) Pituitary Gland ; Models, Theoretical ; Endocrine Cells ; Action Potentials
    Language English
    Publishing date 2024-01-30
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1011811
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Network Properties of Electrically Coupled Bursting Pituitary Cells.

    Fazli, Mehran / Bertram, Richard

    Frontiers in endocrinology

    2022  Volume 13, Page(s) 936160

    Abstract: The endocrine cells of the anterior pituitary gland are electrically active when stimulated or, in some cases, when not inhibited. The activity pattern thought to be most effective in releasing hormones is bursting, which consists of depolarization with ... ...

    Abstract The endocrine cells of the anterior pituitary gland are electrically active when stimulated or, in some cases, when not inhibited. The activity pattern thought to be most effective in releasing hormones is bursting, which consists of depolarization with small spikes that are much longer than single spikes. Although a majority of the research on cellular activity patterns has been performed on dispersed cells, the environment
    MeSH term(s) Action Potentials ; Endocrine Cells ; Hormones ; Pituitary Gland
    Chemical Substances Hormones
    Language English
    Publishing date 2022-07-06
    Publishing country Switzerland
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2592084-4
    ISSN 1664-2392
    ISSN 1664-2392
    DOI 10.3389/fendo.2022.936160
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Effect of heating on disposal point of main edible oils available in Iran market.

    Mohammadian Fazli, Mehran / Zanganeh, Hamid / Hassanzadazar, Hassan

    Food science & nutrition

    2022  Volume 10, Issue 12, Page(s) 4394–4402

    Abstract: Deep frying is the most common method used for food preparation worldwide, which can lead to several chemical changes in used fat or oil in frying process including oxidation and polymerization. This study aimed to determine the effect of heating and ... ...

    Abstract Deep frying is the most common method used for food preparation worldwide, which can lead to several chemical changes in used fat or oil in frying process including oxidation and polymerization. This study aimed to determine the effect of heating and different storage conditions on the disposal point of four types of the most common edible oils available in the Iranian market without and with the presence of food in terms of acid value (AV) and total polar compounds (TPC). AV and TPC of three types of marketed sunflower oil (especially for frying, cooking, solid vegetable) and ghee heated at 110, 150, 180, and 200°C with a portable oil meter DOM-24 (ATAGO, Japan) were determined. They were measured without the presence of food at four different temperatures and four different times in five storage conditions and with the presence of frying food (chicken and potatoes) at 110°C for 20 min in three replicates. The results showed that the AV and TPC contents in the case of ghee were above national and international standards without the presence of food. Also, in the process of frying chicken and potato, the reusability of all the studied oils was not possible for the second time and reached the disposal point. The increase in the rate of AV and TPC of oils was: ghee (Kermanshahi oil) > liquid cooking oil > frying oil ≥ solid vegetable oil.
    Language English
    Publishing date 2022-08-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2703010-6
    ISSN 2048-7177
    ISSN 2048-7177
    DOI 10.1002/fsn3.3033
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Fast-slow analysis of a stochastic mechanism for electrical bursting.

    Fazli, Mehran / Vo, Theodore / Bertram, Richard

    Chaos (Woodbury, N.Y.)

    2021  Volume 31, Issue 10, Page(s) 103128

    Abstract: Electrical bursting oscillations in neurons and endocrine cells are activity patterns that facilitate the secretion of neurotransmitters and hormones and have been the focus of study for several decades. Mathematical modeling has been an extremely useful ...

    Abstract Electrical bursting oscillations in neurons and endocrine cells are activity patterns that facilitate the secretion of neurotransmitters and hormones and have been the focus of study for several decades. Mathematical modeling has been an extremely useful tool in this effort, and the use of fast-slow analysis has made it possible to understand bursting from a dynamic perspective and to make testable predictions about changes in system parameters or the cellular environment. It is typically the case that the electrical impulses that occur during the active phase of a burst are due to stable limit cycles in the fast subsystem of equations or, in the case of so-called "pseudo-plateau bursting," canards that are induced by a folded node singularity. In this article, we show an entirely different mechanism for bursting that relies on stochastic opening and closing of a key ion channel. We demonstrate, using fast-slow analysis, how the short-lived stochastic channel openings can yield a much longer response in which single action potentials are converted into bursts of action potentials. Without this stochastic element, the system is incapable of bursting. This mechanism can describe stochastic bursting in pituitary corticotrophs, which are small cells that exhibit a great deal of noise as well as other pituitary cells, such as lactotrophs and somatotrophs that exhibit noisy bursts of electrical activity.
    MeSH term(s) Action Potentials ; Ion Channels ; Models, Theoretical ; Neurons ; Pituitary Gland
    Chemical Substances Ion Channels
    Language English
    Publishing date 2021-11-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1472677-4
    ISSN 1089-7682 ; 1054-1500
    ISSN (online) 1089-7682
    ISSN 1054-1500
    DOI 10.1063/5.0059338
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Phantom bursting may underlie electrical bursting in single pancreatic β-cells.

    Fazli, Mehran / Vo, Theodore / Bertram, Richard

    Journal of theoretical biology

    2020  Volume 501, Page(s) 110346

    Abstract: Insulin is secreted by pancreatic β-cellsthat are electrically coupled into micro-organs called islets of Langerhans. The secretion is due to the influx of ... ...

    Abstract Insulin is secreted by pancreatic β-cellsthat are electrically coupled into micro-organs called islets of Langerhans. The secretion is due to the influx of Ca
    MeSH term(s) Calcium/metabolism ; Glucose/metabolism ; Insulin/metabolism ; Insulin Secretion ; Insulin-Secreting Cells/metabolism ; Islets of Langerhans/metabolism ; Models, Biological
    Chemical Substances Insulin ; Glucose (IY9XDZ35W2) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2020-06-04
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2972-5
    ISSN 1095-8541 ; 0022-5193
    ISSN (online) 1095-8541
    ISSN 0022-5193
    DOI 10.1016/j.jtbi.2020.110346
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Chronic stress facilitates bursting electrical activity in pituitary corticotrophs.

    Duncan, Peter J / Fazli, Mehran / Romanò, Nicola / Le Tissier, Paul / Bertram, Richard / Shipston, Michael J

    The Journal of physiology

    2021  Volume 600, Issue 2, Page(s) 313–332

    Abstract: Coordination of an appropriate stress response is dependent upon anterior pituitary corticotroph excitability in response to hypothalamic secretagogues and glucocorticoid negative feedback. A key determinant of corticotroph excitability is large ... ...

    Abstract Coordination of an appropriate stress response is dependent upon anterior pituitary corticotroph excitability in response to hypothalamic secretagogues and glucocorticoid negative feedback. A key determinant of corticotroph excitability is large conductance calcium- and voltage-activated (BK) potassium channels that are critical for promoting corticotrophin-releasing hormone (CRH)-induced bursting that enhances adrenocorticotrophic hormone secretion. Previous studies revealed hypothalamic-pituitary-adrenal axis hyperexcitability following chronic stress (CS) is partly a function of increased corticotroph output. Thus, we hypothesise that chronic stress promotes corticotroph excitability through a BK-dependent mechanism. Corticotrophs from CS mice displayed significant increase in spontaneous bursting, which was suppressed by the BK blocker paxilline. Mathematical modelling reveals that the time constant of BK channel activation, plus properties and proportion of BK channels functionally coupled to L-type Ca
    MeSH term(s) Animals ; Corticotrophs/metabolism ; Corticotropin-Releasing Hormone/metabolism ; Hypothalamo-Hypophyseal System/metabolism ; Large-Conductance Calcium-Activated Potassium Channels/metabolism ; Male ; Mice ; Pituitary-Adrenal System/metabolism
    Chemical Substances Large-Conductance Calcium-Activated Potassium Channels ; Corticotropin-Releasing Hormone (9015-71-8)
    Language English
    Publishing date 2021-12-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 3115-x
    ISSN 1469-7793 ; 0022-3751
    ISSN (online) 1469-7793
    ISSN 0022-3751
    DOI 10.1113/JP282367
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Dataset for adsorptive removal of tetracycline (TC) from aqueous solution via natural light weight expanded clay aggregate (LECA) and LECA coated with manganese oxide nanoparticles in the presence of H2O2

    Sepehr, Mohammad Noori / Allani, Farideh / Zarrabi, Mansur / Darvishmotevalli, Mohammad / Vasseghian, Yasser / Fadaei, Saeid / Fazli, Mehran Mohammadian

    Data in Brief. 2019 Feb., v. 22

    2019  

    Abstract: In this data article, natural (NL) and manganese oxide-modified LECA (MML) adsorbents were applied for adsorptive removal of Tetracycline (TC) from aqueous solution. The used adsorbents was characterized using fourier transform infrared (FTIR) ... ...

    Abstract In this data article, natural (NL) and manganese oxide-modified LECA (MML) adsorbents were applied for adsorptive removal of Tetracycline (TC) from aqueous solution. The used adsorbents was characterized using fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence spectroscopy (XRF). The chemical analysis of XRF data revealed increased chemical composition of Mn as MnO to 8.96 wt%. The SEM patterns were illustrated the extent of surface and enhanced porosity in MML with Mn. In optimum operational conditions, maximum removal percentage of TC was achieved at 51.5 and 99.4% using NL and MML, respectively. The maximum adsorption capacities obtained from Langmuir modeling were 6.89 and 9.24 for NL and MML, respectively. The modeling of the adsorption kinetics revealed that TC adsorption by both NL and MML adsorbents was best-fitted with a pseudo-first-order model (R² = 0.978). The isotherm studies of TC adsorption by MML showed that the Freundlich isotherm was the most appropriate model, with a higher coefficient of determination. The obtained data was illustrated that high competitive capacity of chloride and hardness ions compared with other ions against TC adsorption.
    Keywords Fourier transform infrared spectroscopy ; X-ray diffraction ; X-ray fluorescence spectroscopy ; adsorbents ; adsorption ; aqueous solutions ; chemical analysis ; chemical composition ; chlorides ; clay ; data collection ; hardness ; manganese ; manganese monoxide ; models ; porosity ; solar radiation ; sorption isotherms ; tetracycline
    Language English
    Dates of publication 2019-02
    Size p. 676-686.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 2786545-9
    ISSN 2352-3409
    ISSN 2352-3409
    DOI 10.1016/j.dib.2018.12.077
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: Administration of Intravenous Zoledronic Acid Every 3 Months vs. Annually in β-thalassemia Patients with Low Bone Mineral Density: a Retrospective Comparison of Efficacy.

    Darvishi-Khezri, Hadi / Kosaryan, Mehrnoush / Akbarzadeh, Rosseta / Aliasgharian, Aily / Fazli, Mehran

    Medical archives (Sarajevo, Bosnia and Herzegovina)

    2018  Volume 72, Issue 3, Page(s) 170–173

    Abstract: Introduction: The benefit of annual administration of zoledronic acid in the management of thalassemia-associated osteoporosis is unknown.: Aim: The aims of this study were to evaluate the efficacy of treatment with two different dosing regimens of ... ...

    Abstract Introduction: The benefit of annual administration of zoledronic acid in the management of thalassemia-associated osteoporosis is unknown.
    Aim: The aims of this study were to evaluate the efficacy of treatment with two different dosing regimens of IV zoledronic acid (annually versus every 3 months) for increasing low bone mineral density (BMD) in patients with osteoporosis associated with β-thalassemia as annually and 3-monthly on bone density in patients.
    Materials and methods: This retrospective, single-center study analyzed patients' clinical records and bone density measurements. Those enrolled in the study were 14 to 53 years of age, had documented β-thalassemia, and were treated with IV zoledronic acid on either an annual or every 3 months dosing regimen. Dual-energy X-ray absorptiometry was used to obtain the
    Results: Thirty-four patients were enrolled in the study; 15 (44.1%) had been treated annually, and 19 (55.9%) had been treated every month. In patients receiving treatment with the once-yearly dose of zoledronic acid, significant increases were observed in the lumbar spine BMD
    Conclusions: In patients with thalassemia-associated osteopenia, annual treatment with zoledronic acid increases lumbar spine bone density while being more effective, less expensive, and associated with fewer adverse events than dosing every 3 months.
    MeSH term(s) Absorptiometry, Photon ; Adult ; Bone Density/drug effects ; Bone Density Conservation Agents/administration & dosage ; Dose-Response Relationship, Drug ; Drug Administration Schedule ; Female ; Femur Neck/diagnostic imaging ; Humans ; Iran ; Lumbar Vertebrae/diagnostic imaging ; Male ; Osteoporosis/drug therapy ; Osteoporosis/etiology ; Osteoporosis/physiopathology ; Retrospective Studies ; Treatment Outcome ; Zoledronic Acid/administration & dosage ; beta-Thalassemia/complications ; beta-Thalassemia/drug therapy ; beta-Thalassemia/physiopathology
    Chemical Substances Bone Density Conservation Agents ; Zoledronic Acid (6XC1PAD3KF)
    Language English
    Publishing date 2018-07-26
    Publishing country Bosnia and Herzegovina
    Document type Comparative Study ; Journal Article
    ZDB-ID 128782-5
    ISSN 1986-5961 ; 0025-8083 ; 0350-199X
    ISSN (online) 1986-5961
    ISSN 0025-8083 ; 0350-199X
    DOI 10.5455/medarh.2018.72.170-173
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: The Short Term Effects of Shock-Wave Therapy for Tennis Elbow: a Clinical Trial Study.

    Razavipour, Mehran / Azar, Masoud Shayesteh / Kariminasab, Mohamad Hosein / Gaffari, Salman / Fazli, Mehran

    Acta informatica medica : AIM : journal of the Society for Medical Informatics of Bosnia & Herzegovina : casopis Drustva za medicinsku informatiku BiH

    2018  Volume 26, Issue 1, Page(s) 54–56

    Abstract: Background: Tennis elbow is one of the most often diagnosed pathology of the upper extremity and different treatments have been suggested for this disease, so this study was to investigate the effects of extracorporeal shock wave therapy in Tennis elbow ...

    Abstract Background: Tennis elbow is one of the most often diagnosed pathology of the upper extremity and different treatments have been suggested for this disease, so this study was to investigate the effects of extracorporeal shock wave therapy in Tennis elbow treatment.
    Materials and methods: We design a before and after clinical trial study (registry number: IRCT2012072610405N1) and investigated 40 patients with tennis elbow disease. All patients received 2000 pulses extracorporeal shock wave by piezoelectric device (WOLF Company) daily for one-week. The severity of pain was the primary outcome and measured with visual analogue scale (VAS). Secondary outcome was the ability to perform daily activities using questionnaire's quick DASH (Disabilities of the Arm, Shoulder and Hand). Primary and secondary outcomes at baseline, 30 and 60 days after intervention were measured.
    Results: The mean age of patients was 43.80±8.97 years and 28 patients (70%) were female. The mean duration of disease was 6.5 ± 7.9 month. The mean score of VAS pain score reduced from 7.25±1.54cm (median=7cm) before treatment to 2.76±2.08cm (median=2cm) at 60 days after the end of treatment (P<0.001). The Quick Dash score reduced significantly from 25.20±5.31 (median=25) before treatment to 8.69±8.32 (median=6) at 60 days after the treatment (P<0.001).
    Conclusion: For newly diagnosed patients with tennis elbow, extracorporeal shock wave therapy can reduce the severity of pain and improve daily activity.
    Language English
    Publishing date 2018-05-02
    Publishing country Bosnia and Herzegovina
    Document type Journal Article
    ZDB-ID 2558601-4
    ISSN 1986-5988 ; 0353-8109
    ISSN (online) 1986-5988
    ISSN 0353-8109
    DOI 10.5455/aim.2018.26.54-56
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Erratum to: Which pamidronate protocol is the best for treating osteoporosis in beta-thalassemia major?

    Kowsaryan, Mehrnoush / Rahimi, Shiva / Zafari, Mandana / Fazli, Mehran / Mousavi, Masoomeh

    Annals of hematology

    2016  Volume 95, Issue 11, Page(s) 1929

    Language English
    Publishing date 2016-08-21
    Publishing country Germany
    Document type Published Erratum
    ZDB-ID 1064950-5
    ISSN 1432-0584 ; 0939-5555 ; 0945-8077
    ISSN (online) 1432-0584
    ISSN 0939-5555 ; 0945-8077
    DOI 10.1007/s00277-016-2799-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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