Effects of time-controlled adaptive ventilation on cardiorespiratory parameters and inflammatory response in experimental emphysema

2022 ◽  
Author(s):  
Milena Vasconcellos de Oliveira ◽  
Raquel F Magalhães ◽  
Nazareth N. Rocha ◽  
Marcos V.S. Fernandes ◽  
Mariana Alves Antunes ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Volume Fraction ◽  
Intratracheal Instillation ◽  
Lung Damage ◽  
Lung Ultrasonography ◽  
Ejection Time ◽  
Mechanically Ventilated ◽  
Lung Emphysema ◽  
And Biological Markers ◽  
The Impact

The time-controlled adaptive ventilation (TCAV) method attenuates lung damage in acute respiratory distress syndrome. However, so far, no study has evaluated the impact of the TCAV method on ventilator-induced lung injury (VILI) and cardiac function in emphysema. We hypothesized that the use of the TCAV method to achieve an expiratory flow termination/expiratory peak flow (EFT/EPF) of 25% could reduce VILI and improve right ventricular function in elastase-induced lung emphysema in rats. Five weeks after the last intratracheal instillation of elastase, animals were anesthetized and mechanically ventilated for 1 h using TCAV adjusted to either EFT/EPF 25% or EFT/EPF 75%, the latter often applied in ARDS. Pressure-controlled ventilation (PCV) groups with positive end-expiratory pressure levels similar to positive end-release pressure in TCAV with EFT/EPF 25% and EFT/EPF 75% were also analyzed. Echocardiography and lung ultrasonography were monitored. Lung morphometry, alveolar heterogeneity, and biological markers related to inflammation (interleukin [IL]-6, CINC-1), alveolar pulmonary stretch (amphiregulin), lung matrix damage (metalloproteinase [MMP]-9) were assessed. EFT/EPF 25% reduced respiratory system peak pressure, mean linear intercept, B lines at lung ultrasonography, and increased pulmonary acceleration time/pulmonary ejection time ratio compared with EFT/EPF 75%. The volume fraction of mononuclear cells, neutrophils, and expression of IL-6, CINC-1, amphiregulin, and MMP-9 were lower with EFT/EPF 25% than with EFT/EPF 75%. In conclusion, TCAV with EFT/EPF 25%, compared with EFT/EPF 75%, led to less lung inflammation, hyperinflation, and pulmonary arterial hypertension, which may be a promising strategy for patients with emphysema.

scholarly journals Nanofluid flow containing carbon nanotubes with quartic autocatalytic chemical reaction and Thompson and Troian slip at the boundary

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Muhammad Ramzan ◽  
Jae Dong Chung ◽  
Seifedine Kadry ◽  
Yu-Ming Chu ◽  
Muhammad Akhtar
Keyword(s):  
Mathematical Model ◽  
Carbon Nanotubes ◽  
Drag Force ◽  
Chemical Reaction ◽  
Slip Velocity ◽  
Volume Fraction ◽  
Surface Drag ◽  
Nanofluid Flow ◽  
Velocity Parameter ◽  
The Impact

Abstract A mathematical model is envisioned to discourse the impact of Thompson and Troian slip boundary in the carbon nanotubes suspended nanofluid flow near a stagnation point along an expanding/contracting surface. The water is considered as a base fluid and both types of carbon nanotubes i.e., single-wall (SWCNTs) and multi-wall (MWCNTs) are considered. The flow is taken in a Dacry-Forchheimer porous media amalgamated with quartic autocatalysis chemical reaction. Additional impacts added to the novelty of the mathematical model are the heat generation/absorption and buoyancy effect. The dimensionless variables led the envisaged mathematical model to a physical problem. The numerical solution is then found by engaging MATLAB built-in bvp4c function for non-dimensional velocity, temperature, and homogeneous-heterogeneous reactions. The validation of the proposed mathematical model is ascertained by comparing it with a published article in limiting case. An excellent consensus is accomplished in this regard. The behavior of numerous dimensionless flow variables including solid volume fraction, inertia coefficient, velocity ratio parameter, porosity parameter, slip velocity parameter, magnetic parameter, Schmidt number, and strength of homogeneous/heterogeneous reaction parameters are portrayed via graphical illustrations. Computational iterations for surface drag force are tabulated to analyze the impacts at the stretched surface. It is witnessed that the slip velocity parameter enhances the fluid stream velocity and diminishes the surface drag force. Furthermore, the concentration of the nanofluid flow is augmented for higher estimates of quartic autocatalysis chemical.

scholarly journals Low-carbon cast microalloyed steel intercritically heat-treated at different temperatures: microstructure and mechanical properties

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Hadi Torkamani ◽  
Shahram Raygan ◽  
Carlos Garcia Mateo ◽  
Yahya Palizdar ◽  
Jafar Rassizadehghani ◽  
...  
Keyword(s):  
Carbon Content ◽  
Volume Fraction ◽  
Block Size ◽  
Tensile Tests ◽  
Total Elongation ◽  
Martensite Phase ◽  
Low Carbon ◽  
Steel Increase ◽  
Different Temperatures ◽  
The Impact

AbstractIn this study, dual-phase (DP, ferrite + martensite) microstructures were obtained by performing intercritical heat treatments (IHT) at 750 and 800 °C followed by quenching. Decreasing the IHT temperature from 800 to 750 °C leads to: (i) a decrease in the volume fraction of austenite (martensite after quenching) from 0.68 to 0.36; (ii) ~ 100 °C decrease in martensite start temperature (Ms), mainly due to the higher carbon content of austenite and its smaller grains at 750 °C; (iii) a reduction in the block size of martensite from 1.9 to 1.2 μm as measured by EBSD. Having a higher carbon content and a finer block size, the localized microhardness of martensite islands increases from 380 HV (800 °C) to 504 HV (750 °C). Moreover, despite the different volume fractions of martensite obtained in DP microstructures, the hardness of the steels remained unchanged by changing the IHT temperature (~ 234 to 238 HV). Applying lower IHT temperature (lower fraction of martensite), the impact energy even decreased from 12 to 9 J due to the brittleness of the martensite phase. The results of the tensile tests indicate that by increasing the IHT temperature, the yield and ultimate tensile strengths of the DP steel increase from 493 to 770 MPa, and from 908 to 1080 MPa, respectively, while the total elongation decreases from 9.8 to 4.5%. In contrast to the normalized sample, formation of martensite in the DP steels could eliminate the yield point phenomenon in the tensile curves, as it generates free dislocations in adjacent ferrite.

scholarly journals Regulation of CTLA-4 and PD-L1 Expression in Relapsing-Remitting Multiple Sclerosis Patients after Treatment with Fingolimod, IFNβ-1α, Glatiramer Acetate, and Dimethyl Fumarate Drugs

2021 ◽  
Vol 11 (8) ◽  
pp. 721
Author(s):  
Afshin Derakhshani ◽  
Zahra Asadzadeh ◽  
Hossein Safarpour ◽  
Patrizia Leone ◽  
Mahdi Abdoli Shadbad ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Mononuclear Cells ◽  
Demyelinating Disease ◽  
Immune Checkpoints ◽  
Peripheral Blood Mononuclear ◽  
Relapsing Remitting ◽  
Remitting Multiple Sclerosis ◽  
Multiple Sclerosis Patients ◽  
Relapsing Remitting Multiple Sclerosis ◽  
The Impact

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) that is characterized by inflammation which typically results in significant impairment in most patients. Immune checkpoints act as co-stimulatory and co-inhibitory molecules and play a fundamental role in keeping the equilibrium of the immune system. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) and Programmed death-ligand 1 (PD-L1), as inhibitory immune checkpoints, participate in terminating the development of numerous autoimmune diseases, including MS. We assessed the CTLA-4 and PD-L1 gene expression in the different cell types of peripheral blood mononuclear cells of MS patients using single-cell RNA-seq data. Additionally, this study outlines how CTLA-4 and PD-L1 expression was altered in the PBMC samples of relapsing-remitting multiple sclerosis (RRMS) patients compared to the healthy group. Finally, it investigates the impact of various MS-related treatments in the CTLA-4 and PD-L1 expression to restrain autoreactive T cells and stop the development of MS autoimmunity.

scholarly journals Lasting effects of prenatal exposure to Cannabis in the retina of the offspring: an experimental study in mice

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Paulo Roberto Arruda Zantut ◽  
Mariana Matera Veras ◽  
Sarah Gomes Menezes Benevenutto ◽  
Angélica Mendonça Vaz Safatle ◽  
Ricardo Augusto Pecora ◽  
...  
Keyword(s):  
Young Adult ◽  
Light Microscopy ◽  
Prenatal Exposure ◽  
Structural Changes ◽  
Volume Fraction ◽  
Clinical Care ◽  
Retinal Layer ◽  
Exposed Population ◽  
The Central Nervous System ◽  
The Impact

Abstract Background Prenatal exposure to Cannabis is a worldwide growing problem. Although retina is part of the central nervous system, the impact of maternal Cannabis use on the retinal development and its postnatal consequences remains unknown. As the prenatal period is potentially sensitive in the normal development of the retina, we hypothesized that recreational use of Cannabis during pregnancy may alter retina structure in the offspring. To test this, we developed a murine model that mimics human exposure in terms of dose and use. Methods Pregnant BalbC mice were exposed daily for 5 min to Cannabis smoke (0.2 g of Cannabis) or filtered air, from gestational day 5 to 18 (N = 10/group). After weaning period, pups were separated and examined weekly. On days 60, 120, 200, and 360 after birth, 10 pups from each group were randomly selected for Spectral Domain Optical Coherence Tomography (SD-OCT) analysis of the retina. All retina layers were measured and inner, outer, and total retina thickness were calculated. Other 37 mice from both groups were sacrificed on days 20, 60, and 360 for retinal stereology (total volume of the retina and volume fraction of each retinal layer) and light microscopy. Means and standard deviations were calculated and MANOVA was performed. Results The retina of animals which mother was exposed to Cannabis during gestation was 17% thinner on day 120 (young adult) than controls (P = 0.003) due to 21% thinning of the outer retina (P = 0.001). The offspring of mice from the exposed group presented thickening of the IS/OS in comparison to controls on day 200 (P < 0.001). In the volumetric analyzes by retinal stereology, the exposed mice presented transitory increase of the IS/OS total volume and volume fraction on day 60 (young adult) compared to controls (P = 0.008 and P = 0.035, respectively). On light microscopy, exposed mice presented thickening of the IS/OS on day 360 (adult) compared to controls (P = 0.03). Conclusion Gestational exposure to Cannabis smoke may cause structural changes in the retina of the offspring that return to normal on mice adulthood. These experimental evidences suggest that children and young adults whose mothers smoked Cannabis during pregnancy may require earlier and more frequent clinical care than the non-exposed population.

scholarly journals Insulation Characteristics of Sisal Fibre/Epoxy Composites

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
A. Shalwan ◽  
M. Alajmi ◽  
A. Alajmi
Keyword(s):  
Volume Fraction ◽  
Fibre Volume Fraction ◽  
Thermal Characteristics ◽  
Fibre Volume ◽  
Point Of View ◽  
Natural Fibres ◽  
Epoxy Composites ◽  
Ongoing Research ◽  
Sisal Fibre ◽  
The Impact

Using natural fibres in civil engineering is the aim of many industrial and academics sectors to overcome the impact of synthetic fibres on environments. One of the potential applications of natural fibres composites is to be implemented in insulation components. Thermal behaviour of polymer composites based on natural fibres is recent ongoing research. In this article, thermal characteristics of sisal fibre reinforced epoxy composites are evaluated for treated and untreated fibres considering different volume fractions of 0–30%. The results revealed that the increase in the fibre volume fraction increased the insulation performance of the composites for both treated and untreated fibres. More than 200% insulation rate was achieved at the volume fraction of 20% of treated sisal fibres. Untreated fibres showed about 400% insulation rate; however, it is not recommended to use untreated fibres from mechanical point of view. The results indicated that there is potential of using the developed composites for insulation purposes.

Experimental Model of Temperature-Driven Nanofluid

2006 ◽  
Vol 129 (6) ◽  
pp. 697-704 ◽  
Author(s):  
A. G. Agwu Nnanna
Keyword(s):  
Heat Transfer ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Small Volume ◽  
Volume Fraction ◽  
Convective Heat Transfer Coefficient ◽  
Isothermal Condition ◽  
Carrier Fluid ◽  
Small Volume Fraction ◽  
The Impact

This paper presents a systematic experimental method of studying the heat transfer behavior of buoyancy-driven nanofluids. The presence of nanoparticles in buoyancy-driven flows affects the thermophysical properties of the fluid and consequently alters the rate of heat transfer. The focus of this paper is to estimate the range of volume fractions that results in maximum thermal enhancement and the impact of volume fraction on Nusselt number. The test cell for the nanofluid is a two-dimensional rectangular enclosure with differentially heated vertical walls and adiabatic horizontal walls filled with 27 nm Al2O3–H2O nanofluid. Simulations were performed to measure the transient and steady-state thermal response of nanofluid to imposed isothermal condition. The volume fraction is varied between 0% and 8%. It is observed that the trend of the temporal and spatial evolution of temperature profile for the nanofluid mimics that of the carrier fluid. Hence, the behaviors of both fluids are similar. Results shows that for small volume fraction, 0.2⩽ϕ⩽2% the presence of the nanoparticles does not impede the free convective heat transfer, rather it augments the rate of heat transfer. However, for large volume fraction ϕ>2%, the convective heat transfer coefficient declines due to reduction in the Rayleigh number caused by increase in kinematic viscosity. Also, an empirical correlation for Nuϕ as a function of ϕ and Ra has been developed, and it is observed that the nanoparticle enhances heat transfer rate even at a small volume fraction.

The impact of nanocolloidal wear-particles on human mononuclear cells

2006 ◽  
Vol 37 (6) ◽  
pp. 563-569 ◽  
Author(s):  
L. E. Podleska ◽  
M. Weuster ◽  
E. Dose ◽  
Chr. A. Kühne ◽  
D. Nast-Kolb ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Wear Particles ◽  
Human Mononuclear Cells ◽  
The Impact

Carfilzomib can induce tumor cell death through selective inhibition of the chymotrypsin-like activity of the proteasome

Blood ◽  
2009 ◽  
Vol 114 (16) ◽  
pp. 3439-3447 ◽  
Author(s):  
Francesco Parlati ◽  
Susan J. Lee ◽  
Monette Aujay ◽  
Erika Suzuki ◽  
Konstantin Levitsky ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Mononuclear Cells ◽  
Proteasome Inhibitors ◽  
Selective Inhibition ◽  
Tumor Cell Death ◽  
Clinical Safety ◽  
Peripheral Blood Mononuclear ◽  
Non Hodgkin Lymphoma ◽  
Proteasome Subunits ◽  
The Impact

Abstract Carfilzomib is a proteasome inhibitor in clinical development that primarily targets the chymotrypsin-like (CT-L) subunits in both the constitutive proteasome (c20S) and the immunoproteasome (i20S). To investigate the impact of inhibiting the CT-L activity with carfilzomib, we set out to quantitate the levels of CT-L subunits β5 from the c20S and LMP7 from the i20S in normal and malignant hematopoietic cells. We found that the i20S is a major form of the proteasome expressed in cells of hematopoietic origin, including multiple myeloma (MM) CD138+ tumor cells. Although specific inhibition of either LMP7 or β5 alone was insufficient to produce an antitumor response, inhibition of all proteasome subunits was cytotoxic to both hematologic tumor cells and peripheral blood mononuclear cells. However, selective inhibition of both β5 and LMP7 was sufficient to induce an antitumor effect in MM, non-Hodgkin lymphoma, and leukemia cells while minimizing the toxicity toward nontransformed cells. In MM tumor cells, CT-L inhibition alone was sufficient to induce proapoptotic sequelae, including proteasome substrate accumulation, Noxa and caspase 3/7 induction, and phospho-eIF2α suppression. These data support a hypothesis that hematologic tumor cells are uniquely sensitive to CT-L inhibition and provide a mechanistic understanding of the clinical safety profile and antitumor activity of proteasome inhibitors.

scholarly journals 1487. Pneumonia due to Co-Infection in the ICU: Detection and Clinical Significance

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S745-S746
Author(s):  
Casey S Zelus ◽  
Michael Blaha ◽  
Kaeli Samsom ◽  
Jasmine R Marcelin ◽  
Trevor C Van Schooneveld ◽  
...  
Keyword(s):  
Clinical Significance ◽  
Diagnostic Testing ◽  
Significant Risk ◽  
Significant Risk Factor ◽  
Categorical Variables ◽  
Chi Square ◽  
Mechanically Ventilated ◽  
Critical Care Units ◽  
Outcomes Measures ◽  
The Impact

Abstract Background Pneumonia is a significant cause of morbidity and mortality, with increasing interest in the detection and clinical significance of co-infection. However, the impact of methodology to obtain lower respiratory samples along with the utility of various microbiological diagnostic testing remains unclear. Methods A single-center retrospective analysis was performed on bronchoalveolar lavage (BAL) samples obtained from mechanically ventilated adults treated in critical care units from August 2012 to December 2017. BAL methodology (bronchoscopic vs blinded), microbiological diagnostic testing, and outcomes measures were obtained. Associations between categorical variables were assessed using Chi-Square or Fisher’s exact tests. Kruskal Wallace tests analyzed differences in distributions of measures between categories based on number of organism types detected. SAS software version 9.4 (SAS Institute Inc., Cary, NC). Results Analysis of the 803 samples that met inclusion criteria found a significant linear association between mortality and number of organism types detected by BAL, with 30 day mortality rates of 43.0%, 47.8%, and 58.3% among those with zero, one, and two or more organisms respectively (p = 0.003). Comparing BALs with at least one organism isolated, the detection of viruses specifically was associated with increased mortality, with the presence and absence of viral organisms corresponding to 56.3% and 46.5% mortality at thirty days (p = 0.03). No association was found between mortality and isolation of acid-fast bacilli, bacteria, or fungi. Co-infection was detected more frequently among bronchoscopic BALs than blinded BALs (26.3% vs 8.6%, p &lt; 0.0001), with more viruses detected bronchoscopic BALs (41.9% vs 13.1%, p &lt; 0.0001), and more bacteria in blinded BALs (41.8% vs 33.0%, p = 0.01). 30 Day Mortality vs Isolation of Specific Organism Types from BAL Number of Organism Types Isolated from BAL Compared to BAL Methodology BAL Methodology vs Isolation of Specific Organism Types Conclusion Co-infection in mechanically ventilated adult patients with pneumonia appears to be a significant risk factor for mortality, with the detection of viral organisms potentially playing an independent role. Within this population, bronchoscopic BALs may have a valuable diagnostic and prognostic methodology. Disclosures All Authors: No reported disclosures

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