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  1. Article: Evaluation of the Tracheal Stenosis Effects on Airway Resistance and Work of Breathing Using Computational Fluid Dynamics.

    Monjezi, Mojdeh / Rismanian, Milad / Kiani, Arda / Abedini, Atefeh / Jamaati, Hamidreza

    Tanaffos

    2024  Volume 22, Issue 2, Page(s) 209–214

    Abstract: Background: Bronchoscopy is one of the most accurate procedures to diagnose airway stenosis which is an invasive procedure. However, a quick and noninvasive estimation of the percent area of obstruction (%AO) of the lumen is helpful in decision-making ... ...

    Abstract Background: Bronchoscopy is one of the most accurate procedures to diagnose airway stenosis which is an invasive procedure. However, a quick and noninvasive estimation of the percent area of obstruction (%AO) of the lumen is helpful in decision-making before performing a bronchoscopy procedure. We hypothesized that there is a relationship between %AO and tracheal resistance against fluid flow.
    Materials and methods: By measuring airway resistance, %AO could be estimated before the procedure. Using computational fluid dynamics (CFD), this study simulates the fluid flow through trachea models with web-liked stenosis using CFD. A cylindrical segment was inserted into the trachea to represent cross-sectional areas corresponding to 20%, 40%, 60%, and 80% AO. The fluid flow and pressure distribution in these models were studied. Our CFD simulations revealed that the tracheal resistance is exponentially increased by %AO.
    Results: The results showed a 130% and 55% increase in lung airway resistance and resistive work of breathing for an 80% AO, respectively. Moreover, a curve-fitted relationship was obtained to estimate %AO based on the measured airway resistance by body plethysmography or forced oscillation technique.
    Conclusion: This pre-estimation is very useful in diagnostic evaluation and treatment planning in patients with tracheal stenosis.
    Language English
    Publishing date 2024-04-02
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2233372-1
    ISSN 1735-0344
    ISSN 1735-0344
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  2. Article: Is There an Ending in Insight for COVID-19?

    Mortaz, Esmaeil / Jamaati, Hamidreza / Adcock, Ian M

    Tanaffos

    2022  Volume 20, Issue 4, Page(s) 294–295

    Language English
    Publishing date 2022-09-28
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2233372-1
    ISSN 1735-0344
    ISSN 1735-0344
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Editorial Note.

    Jamaati, Hamidreza

    Tanaffos

    2015  Volume 14, Issue 2, Page(s) 72

    Language English
    Publishing date 2015-05-21
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2233372-1
    ISSN 1735-0344
    ISSN 1735-0344
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  4. Article ; Online: The effects of face mask specifications on work of breathing and particle filtration efficiency.

    Monjezi, Mojdeh / Jamaati, Hamidreza

    Medical engineering & physics

    2021  Volume 98, Page(s) 36–43

    Abstract: The outbreak of the ongoing coronavirus disease 2019 (COVID-19) pandemic has led to the recommended routine use of face masks to reduce exposure risk. In this study, the increase in work of breathing (WOB) imposed by face masks is theoretically studied ... ...

    Abstract The outbreak of the ongoing coronavirus disease 2019 (COVID-19) pandemic has led to the recommended routine use of face masks to reduce exposure risk. In this study, the increase in work of breathing (WOB) imposed by face masks is theoretically studied for both normals and patients with obstructive and restrictive lung diseases at different levels of activity. The results show a significant increase in WOB due to face masks, which is more severe in higher activity levels. The added WOB is considerable during physical activity and may be intolerable for patients with preexisting lung disease and may contribute to inspiratory muscle fatigue and dyspnea. Moreover, in this study, the effects of the physical properties of a fibrous medium, including thickness, porosity, and fiber diameter, are analyzed on the particle filtration efficiency (PFE) and the added WOB. The relations between the physical properties of the fibrous medium and the added WOB and the PFE are shown on some contour plots as a quick and simple tool to select the desired physical properties for a single layer filter to ensure that the added WOB is comfortable while the PFE is sufficiently high.
    MeSH term(s) COVID-19 ; Filtration ; Humans ; Masks ; SARS-CoV-2 ; Work of Breathing
    Language English
    Publishing date 2021-10-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 1181080-4
    ISSN 1873-4030 ; 1350-4533
    ISSN (online) 1873-4030
    ISSN 1350-4533
    DOI 10.1016/j.medengphy.2021.10.004
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  5. Article: Evaluation of the Effects of PAKDAM, an Invented Device to Get Nitrous Oxide and Oxygen, in the Consumers: A Report of Pilot Study.

    Heydari, Gholamreza / Fakharian, Atefeh / Mirenayat, Maryam Sadat / Abedi, Mohsen / Valizadeh, Behzad / Jamaati, Hamidreza

    Tanaffos

    2024  Volume 22, Issue 2, Page(s) 248–255

    Abstract: Background: Since last decade, a device called PAKDAM (means clean inspiration) was invented in Iran which has been used in some cafe to prepare N: Materials and methods: In a case-control pilot study between September 2021 and March 2022, 152 ... ...

    Abstract Background: Since last decade, a device called PAKDAM (means clean inspiration) was invented in Iran which has been used in some cafe to prepare N
    Materials and methods: In a case-control pilot study between September 2021 and March 2022, 152 individuals were divided into two groups: 76 consumers (case) and 76 non- consumers (control). Both groups were divided into two groups of 36 smokers and 36 non-smokers. Participants signed the participation form and filled out the demographic data questionnaire, and then their vital signs, O
    Results: The subjects who used the device had a mean blood pressure of 123.71±16.11 mmHg, oxygen saturation of 97.2±1.9, exhaled carbon monoxide of 9.8±5.5, and an FVC / FEV1 ratio of 88.5±7.9. These figures in control group were (137.79±18.15) - (94.1±4.2) - (14.3 ± 9.3) and (83.9 ± 10.4), respectively. In addition to the effects on the respiratory system, consumers had lower heart rates and lower systolic and diastolic blood pressures.
    Conclusion: The blood oxygen level and FEV1/FVC ratio were higher in subjects using Pakdam and the amount of exhaled carbon monoxide and blood pressure were lower. This condition was more common in smokers and less in non-smokers. It is possible to see the favorable effects of using Pakdam device on people especially in smokers.
    Language English
    Publishing date 2024-04-14
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2233372-1
    ISSN 1735-0344
    ISSN 1735-0344
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  6. Article: The effects of combination-therapy of tocilizumab and baricitinib on the management of severe COVID-19 cases: a randomized open-label clinical trial.

    Dastan, Farzaneh / Jamaati, Hamidreza / Barati, Saghar / Varmazyar, Shahrzad / Yousefian, Sahar / Niknami, Elmira / Tabarsi, Payam

    Frontiers in pharmacology

    2023  Volume 14, Page(s) 1265541

    Abstract: Background: ...

    Abstract Background:
    Language English
    Publishing date 2023-10-19
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2587355-6
    ISSN 1663-9812
    ISSN 1663-9812
    DOI 10.3389/fphar.2023.1265541
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  7. Article: Trimetazidine May Potentially Confer Neuroprotective Effects against COVID-19-Induced Neurological Sequelae via Inhibition of Death-Associated Protein Kinase 1 (DAPK1) Signaling Pathways: An Evidenced-Based Hypothesis.

    Aghajani, Ali / Khakpourian, Zahra / Bakhthiarzadeh, Soodeh / Adibipour, Fatemeh / Sadr, Makan / Coleman-Fuller, Natalie / Jamaati, Hamidreza / Motaghinejad, Majid

    Tanaffos

    2024  Volume 22, Issue 2, Page(s) 182–186

    Language English
    Publishing date 2024-04-14
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2233372-1
    ISSN 1735-0344
    ISSN 1735-0344
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  8. Article ; Online: Airflow Simulation in Pulmonary Conducting Airways.

    Monjezi, Mojdeh / Jamaati, Hamidreza

    Annals of biomedical engineering

    2019  Volume 47, Issue 12, Page(s) 2353–2354

    MeSH term(s) Adult ; Child ; Humans ; Infant ; Lung ; Pulmonary Emphysema ; Respiratory Physiological Phenomena
    Language English
    Publishing date 2019-09-18
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 185984-5
    ISSN 1573-9686 ; 0191-5649 ; 0090-6964
    ISSN (online) 1573-9686
    ISSN 0191-5649 ; 0090-6964
    DOI 10.1007/s10439-019-02367-1
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  9. Article ; Online: The effects of pressure- versus volume-controlled ventilation on ventilator work of breathing.

    Monjezi, Mojdeh / Jamaati, Hamidreza

    Biomedical engineering online

    2020  Volume 19, Issue 1, Page(s) 72

    Abstract: Background: Measurement of work of breathing (WOB) during mechanical ventilation is essential to assess the status and progress of intensive care patients. Increasing ventilator WOB is known as a risk factor for ventilator-induced lung injury (VILI). In ...

    Abstract Background: Measurement of work of breathing (WOB) during mechanical ventilation is essential to assess the status and progress of intensive care patients. Increasing ventilator WOB is known as a risk factor for ventilator-induced lung injury (VILI). In addition, the minimization of WOB is crucial to facilitate the weaning process. Several studies have assessed the effects of varying inspiratory flow waveforms on the patient's WOB during assisted ventilation, but there are few studies on the different effect of inspiratory flow waveforms on ventilator WOB during controlled ventilation.
    Methods: In this paper, we analyze the ventilator WOB, termed mechanical work (MW) for three common inspiratory flow waveforms both in normal subjects and COPD patients. We use Rohrer's equation for the resistance of the endotracheal tube (ETT) and lung airways. The resistance of pulmonary and chest wall tissue are also considered. Then, the resistive MW required to overcome each component of the respiratory resistance is computed for square and sinusoidal waveforms in volume-controlled ventilation (VCV), and decelerating waveform of flow in pressure-controlled ventilation (PCV).
    Results: The results indicate that under the constant I:E ratio, a square flow profile best minimizes the MW both in normal subjects and COPD patients. Furthermore, the large I:E ratio may be used to lower MW. The comparison of results shows that ETT and lung airways have the main contribution to resistive MW in normals and COPDs, respectively.
    Conclusion: These findings support that for lowering the MW especially in patients with obstructive lung diseases, flow with square waveforms in VCV, are more favorable than decelerating waveform of flow in PCV. Our analysis suggests the square profile is the best choice from the viewpoint of less MW.
    MeSH term(s) Inhalation ; Pressure ; Respiration, Artificial/methods ; Risk Factors ; Tidal Volume ; Ventilators, Mechanical ; Work of Breathing
    Keywords covid19
    Language English
    Publishing date 2020-09-15
    Publishing country England
    Document type Journal Article
    ISSN 1475-925X
    ISSN (online) 1475-925X
    DOI 10.1186/s12938-020-00815-x
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  10. Article ; Online: Neural signature of attention impairment in allergic asthma: an ERP study.

    Gholami-Mahtaj, Leila / Mooziri, Morteza / Bamdad, Sobhan / Mikaili, Mohammad / Jamaati, Hamidreza / Raoufy, Mohammad Reza

    The International journal of neuroscience

    2022  , Page(s) 1–11

    Abstract: ... ...

    Abstract Background
    Language English
    Publishing date 2022-11-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 3061-2
    ISSN 1563-5279 ; 1543-5245 ; 0020-7454
    ISSN (online) 1563-5279 ; 1543-5245
    ISSN 0020-7454
    DOI 10.1080/00207454.2022.2151908
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