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| 6. |
- Ardalan, Maryam, 1979, et al.
(författare)
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Dysmaturation of Somatostatin Interneurons Following Umbilical Cord Occlusion in Preterm Fetal Sheep
- 2019
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Ingår i: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Cerebral white matter injury is the most common neuropathology observed in preterm infants. However, there is increasing evidence that gray matter development also contributes to neurodevelopmental abnormalities. Fetal cerebral ischemia can lead to both neuronal and non-neuronal structural-functional abnormalities, but less is known about the specific effects on interneurons. Objective: In this study we used a well-established animal model of fetal asphyxia in preterm fetal sheep to study neuropathological outcome. We used comprehensive stereological methods to investigate the total number of oligodendrocytes, neurons and somatostatin (STT) positive interneurons as well as 3D morphological analysis of STT cells 14 days following umbilical cord occlusion (UCO) in fetal sheep. Materials and Methods: Induction of asphyxia was performed by 25 min of complete UCO in five preterm fetal sheep (98-100 days gestational age). Seven, non-occluded twins served as controls. Quantification of the number of neurons (NeuN), STT interneurons and oligodendrocytes (Olig2, CNPase) was performed on fetal brain regions by applying optical fractionator method. A 3D morphological analysis of STT interneurons was performed using IMARIS software. Results: The number of Olig2, NeuN, and STT positive cells were reduced in IGWM, caudate and putamen in UCO animals compared to controls. There were also fewer STT interneurons in the ventral part of the hippocampus, the subiculum and the entorhinal cortex in UCO group, while other parts of cortex were virtually unaffected (p > 0.05). Morphologically, STT positive interneurons showed a markedly immature structure, with shorter dendritic length and fewer dendritic branches in cortex, caudate, putamen, and subiculum in the UCO group compared with control group (p < 0.05). Conclusion: The significant reduction in the total number of neurons and oligodendrocytes in several brain regions confirm previous studies showing susceptibility of both neuronal and non-neuronal cells following fetal asphyxia. However, in the cerebral cortex significant dysmaturation of STT positive neurons occurred in the absence of cell loss. This suggests an abnormal maturation pattern of GABAergic interneurons in the cerebral cortex, which might contribute to neurodevelopmental impairment in preterm infants and could implicate a novel target for neuroprotective therapies.
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| 7. |
- Ardalan, Maryam, 1979, et al.
(författare)
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Rapid effects of S-ketamine on the morphology of hippocampal astrocytes and BDNF serum levels in a sex-dependent manner
- 2020
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Ingår i: European Neuropsychopharmacology. - : Elsevier BV. - 0924-977X .- 1873-7862. ; 32, s. 94-103
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Tidskriftsartikel (refereegranskat)abstract
- The prevalence of major depressive disorder (MDD) is higher in women than men. Importantly, a differential behavioral response by sex to the antidepressant response to ketamine in rodents has been reported. Mechanistically, male depressed-like animals showed an increased spine density after ketamine treatment via restoration of synaptic protein levels while those proteins were not altered in female rats. In addition, preclinical studies indicate that the impairment of astrocytic plasticity is one of the contributing mechanisms in the pathophysiology of MDD. Accordingly, in this study, we determined the effect of sex on the rapid morphological alteration of hippocampal astrocytes and the serum level of BDNF one hour after S-ketamine injection. A single intraperitoneal dose of S-ketamine (15 mg/kg) or saline was injected to the male and female Flinders Sensitive Line (FSL) rats, a genetic animal model of depression and their brains were perfused one hour after treatment. The size of the GFAP positive astrocytes in the hippocampal subregions was measured. The volume of different hippocampal subregions was assessed using the Cavalieri estimator. Moreover, serum levels of BDNF were measured with enzyme-linked immunosorbent assay (ELISA) kits. The volume of hippocampal subregions significantly increased one hour after S-ketamine in both male and female FSL animals. However, a substantial alteration in the morphology of the hippocampal astrocytes was observed only in the female rats. Additionally, significantly increased serum BDNF levels in the female depressed rats were observed one hour after S-ketamine treatment. Our results indicate that the rapid effects of S-ketamine on the morphology of the hippocampal astrocytes and the serum level of BDNF are sex-dependent.
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| 11. |
- Dudink, I., et al.
(författare)
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An Optimized and Detailed Step-by-Step Protocol for the Analysis of Neuronal Morphology in Golgi-Stained Fetal Sheep Brain
- 2022
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Ingår i: Developmental neuroscience. - : S. Karger AG. - 0378-5866 .- 1421-9859. ; 44:4-5, s. 344-362
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Tidskriftsartikel (refereegranskat)abstract
- Antenatal brain development during the final trimester of human pregnancy is a time when mature neurons become increasingly complex in morphology, through axonal and dendritic outgrowth, dendritic branching, and synaptogenesis, together with myelin production. Characterizing neuronal morphological development over time is of interest to developmental neuroscience and provides the framework to measure gray matter pathology in pregnancy compromise. Neuronal microstructure can be assessed with Golgi staining, which selectively stains a small percentage (1-3%) of neurons and their entire dendritic arbor. Advanced imaging processing and analysis tools can then be employed to quantitate neuronal cytoarchitecture. Traditional Golgi-staining protocols have been optimized, and commercial kits are readily available offering improved speed and sensitivity of Golgi staining to produce consistent results. Golgi-stained tissue is then visualized under light microscopy and image analysis may be completed with several software programs for morphological analysis of neurons, including freeware and commercial products. Each program requires optimization, whether semiautomated or automated, requiring different levels of investigator intervention and interpretation, which is a critical consideration for unbiased analysis. Detailed protocols for fetal ovine brain tissue are lacking, and therefore, we provide a step-by-step workflow of computer software analysis for morphometric quantification of Golgi-stained neurons. Here, we utilized the commonly applied FD Rapid GolgiStain kit (FD NeuroTechnologies) on ovine fetal brains collected at 127 days (0.85) of gestational age for the analysis of CA1 pyramidal neurons in the hippocampus. We describe the step-by-step protocol to retrieve neuronal morphometrics using Imaris imaging software to provide quantification of apical and basal dendrites for measures of dendrite length (mu m), branch number, branch order, and Sholl analysis (intersections over radius). We also detail software add-ons for data retrieval of dendritic spines including the number of spines, spine density, and spine classification, which are critical indicators of synaptic function. The assessment of neuronal morphology in the developing brain using Rapid-Golgi and Imaris software is labor-intensive, particularly during the optimization period. The methodology described in this step-by-step description is novel, detailed, and aims to provide a reproducible, working protocol to quantify neuronal cytoarchitecture with simple descriptions that will save time for the next users of these commonly used techniques.
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| 16. |
- Ardalan, A., et al.
(författare)
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Post-disaster quality of life among older survivors five years after the Bam earthquake : implications for recovery policy
- 2011
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Ingår i: Ageing & Society. - 0144-686X .- 1469-1779. ; 31:2, s. 179-196
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Tidskriftsartikel (refereegranskat)abstract
- Older people are among the most vulnerable in major disasters. In their aftermath, it is crucial to institute efforts that will maintain a high level of elders' quality of life (QoL). This paper presents QoL assessments of elderly survivors five years after the Bam earthquake in Iran, and evaluates the determinants. A cross-sectional analysis of 210 randomly-selected survivors was carried out in 2008 using the WHOQOL-BREF questionnaire. A comparison of the results with data on the general population showed that experiencing the earthquake may adversely affect psychological dimensions of QoL even five years after, but paradoxically the earthquake resulted in better social relationships in affected communities than in the general population. Lower QoL associated with female gender, higher age, living alone, severe earthquake-related injury, poor quality of living conditions, increased dependency in the activities of daily living, living in an urban area, and being temporarily housed. Recovery experts and donors should carry out long-term monitoring of health status and QoL in disaster-affected communities, with a focus on psychological wellbeing. Intervention programmes that emphasise post-disaster quality of care and satisfactory housing may lead to better QoL of the victims and may shorten the recovery phase.
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| 17. |
- Ardalan, Maryam, 1979, et al.
(författare)
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Sex-Dependent Gliovascular Interface Abnormality in the Hippocampus following Postnatal Immune Activation in Mice
- 2022
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Ingår i: Developmental neuroscience. - : S. Karger AG. - 0378-5866 .- 1421-9859. ; 44:4-5, s. 320-330
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Tidskriftsartikel (refereegranskat)abstract
- The neuro-gliovascular unit is a crucial structure for providing a balanced well-functioning environment for neurons and their synapses. Activation of the immune system during the developmental period is believed to affect the gliovascular unit, which may trigger neurodevelopmental and neurological/neuropsychiatric diseases. In this study, we hypothesized that vulnerability of the male brain to a neonatal insult was conditioned by sex-dependent differences in the impairment of the hippocampal gliovascular unit. Male and female C57BL/6J pups received lipopolysaccharide (LPS) (1 mg/kg) or saline on postnatal day (P) 5. Brains were collected at P12 and morphological quantifications of hippocampal fibrillary glial acid protein (GFAP(+)) astrocytes and ionized calcium-binding adaptor molecule 1 protein (Iba1+) microglia were performed by using 3-D image analysis together with measuring the length of CD31(+) and aquaporin-4 (AQP4(+)) vessels. We found a significant increase in the length of CD31(+) capillaries in the male LPS group compared to the saline group; however, coverage of capillaries by astrocytic end-feet (AQP4(+)) was significantly reduced. In contrast, there was a significant increase in AQP4(+) capillary length in female pups 1 week after LPS injection. GFAP(+) astrocytes via morphological changes in the hippocampus showed significant enhancement in the activity 1 week following LPS injection in male mice. We propose that neonatal inflammation could induce susceptibility to neurodevelopmental disorders through modification of hippocampal gliovascular interface in a sex-dependent manner.
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| 19. |
- Bay, V., et al.
(författare)
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Flinders sensitive line rats are resistant to infarction following transient occlusion of the middle cerebral artery
- 2020
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Ingår i: Brain Research. - : Elsevier BV. - 0006-8993. ; 1737
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Tidskriftsartikel (refereegranskat)abstract
- Background: Depression is a common complication of stroke and increases the risk of mortality and disability. Pre-stroke depression is a possible risk factor for stroke and has also been linked to adverse outcomes. The underlying mechanisms linking depression and stroke remain unclear. Preclinical models may provide novel insights, but models reflecting both conditions are lacking. Methods: In this study, we investigated the effects of a 45-min transient middle cerebral artery occlusion (MCAo) on infarct size in male adult Flinders Sensitive Line rats, a genetic animal model of depression, and their control strains Flinders Resistant Line and Sprague-Dawley rats. Infarct size was assessed by tetrazolium chloride (TTC) and microtubule-associated protein 2 (MAP2) staining after 48 h of reperfusion. Angiograms of the vascular structure of naive animals were produced with a mu-CT scanner. Results: Both Flinders strains had significantly smaller infarcts following MCAo compared to Sprague-Dawley rats. This effect does not appear to be due to changes in cerebrovascular architecture, as indicated by an initial exploration of vascular organization using angiograms, or body temperature regulation. Conclusions: Our study suggests that the rat strain does not influence infarct volumes following MCAo.
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| 20. |
- Chumak, Tetyana, 1982, et al.
(författare)
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Maternal n-3 Polyunsaturated Fatty Acid Enriched Diet Commands Fatty Acid Composition in Postnatal Brain and Protects from Neonatal Arterial Focal Stroke
- 2022
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Ingår i: Translational Stroke Research. - : Springer Science and Business Media LLC. - 1868-4483 .- 1868-601X. ; 13:3, s. 449-461
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Tidskriftsartikel (refereegranskat)abstract
- The fetus is strongly dependent on nutrients from the mother, including polyunsaturated fatty acids (PUFA). In adult animals, n-3 PUFA ameliorates stroke-mediated brain injury, but the modulatory effects of different PUFA content in maternal diet on focal arterial stroke in neonates are unknown. This study explored effects of maternal n-3 or n-6 enriched PUFA diets on neonatal stroke outcomes. Pregnant mice were assigned three isocaloric diets until offspring reached postnatal day (P) 10-13: standard, long-chain n-3 PUFA (n-3) or n-6 PUFA (n-6) enriched. Fatty acid profiles in plasma and brain of mothers and pups were determined by gas chromatography-mass spectrometry and cytokines/chemokines by multiplex protein analysis. Transient middle cerebral artery occlusion (tMCAO) was induced in P9-10 pups and cytokine and chemokine accumulation, caspase-3 and calpain-dependent spectrin cleavage and brain infarct volume were analyzed. The n-3 diet uniquely altered brain lipid profile in naive pups. In contrast, cytokine and chemokine levels did not differ between n-3 and n-6 diet in naive pups. tMCAO triggered accumulation of inflammatory cytokines and caspase-3-dependent and -independent cell death in ischemic-reperfused regions in pups regardless of diet, but magnitude of neuroinflammation and caspase-3 activation were attenuated in pups on n-3 diet, leading to protection against neonatal stroke. In conclusion, maternal/postnatal n-3 enriched diet markedly rearranges neonatal brain lipid composition and modulates the response to ischemia. While standard diet is sufficient to maintain low levels of inflammatory cytokines and chemokines under physiological conditions, n-3 PUFA enriched diet, but not standard diet, attenuates increases of inflammatory cytokines and chemokines in ischemic-reperfused regions and protects from neonatal stroke.
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| 21. |
- El Bairi, Khalid, et al.
(författare)
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The tale of TILs in breast cancer: A report from The International Immuno-Oncology Biomarker Working Group
- 2021
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Ingår i: npj Breast Cancer. - : Springer Science and Business Media LLC. - 2374-4677. ; 7:1
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Forskningsöversikt (refereegranskat)abstract
- The advent of immune-checkpoint inhibitors (ICI) in modern oncology has significantly improved survival in several cancer settings. A subgroup of women with breast cancer (BC) has immunogenic infiltration of lymphocytes with expression of programmed death-ligand 1 (PD-L1). These patients may potentially benefit from ICI targeting the programmed death 1 (PD-1)/PD-L1 signaling axis. The use of tumor-infiltrating lymphocytes (TILs) as predictive and prognostic biomarkers has been under intense examination. Emerging data suggest that TILs are associated with response to both cytotoxic treatments and immunotherapy, particularly for patients with triple-negative BC. In this review from The International Immuno-Oncology Biomarker Working Group, we discuss (a) the biological understanding of TILs, (b) their analytical and clinical validity and efforts toward the clinical utility in BC, and (c) the current status of PD-L1 and TIL testing across different continents, including experiences from low-to-middle-income countries, incorporating also the view of a patient advocate. This information will help set the stage for future approaches to optimize the understanding and clinical utilization of TIL analysis in patients with BC.
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| 22. |
- Gober, R., et al.
(författare)
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Microglia activation in postmortem brains with schizophrenia demonstrates distinct morphological changes between brain regions
- 2022
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Ingår i: Brain Pathology. - : Wiley. - 1015-6305 .- 1750-3639. ; 32:1
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Tidskriftsartikel (refereegranskat)abstract
- Schizophrenia (SCZ) is a psychiatric disorder that can include symptoms of disorganized speech and thoughts with uncertain underlying mechanisms possibly linked to over-activated microglia. In this study, we used brain samples from sixteen donors with SCZ and thirteen control donors to assess the differential activation of microglia by quantifying density and 3D reconstruction of microglia stained with ionized calcium-binding adaptor molecule-1 (Iba1). Our samples consisted of sections from the frontal, temporal, and cingulate cortical gray matter, subcortical white matter regions (SCWM), and included the anterior corpus callosum. In the first series of studies, we performed a density analysis followed by a spatial analysis to ascertain the microglial density, distribution, and soma size in SCZ brains. Second, we performed a series of morphological quantification techniques to investigate the arborization patterns of the microglia in SCZ. The results demonstrated an increase in microglia density in the cortical gray matter regions in SCZ cases, while in the SCWM, there was a significant increase in microglia density in the frontal and temporal, but not in the other brain regions of interest (ROIs). Spatial analysis using the "nearest neighbor" demonstrated that there was no effect in "clustering", but there were shorter distances between microglia seen in the SCZ cases. The morphological measures showed that there was a region-dependent increase in the microglia soma size in the SCZ cases while the Sholl analysis revealed a significant decrease in the microglia arborization in the SCZ cases across all the ROI's studied. An in-depth 3D reconstruction of microglia in Brodmann area 9 cortical region found that there was a significant association between age and reduced microglial arborization in the SCZ cases. This region-dependent age association can help determine whether longitudinal changes in microglial activation across age are brain region-dependent, which may point to potential therapeutic targets.
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| 23. |
- Javadi, Ardalan, 1984, et al.
(författare)
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Swirling flow in a conical diffuser generated with rotor-stator interaction
- 2016
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Ingår i: ERCOFTAC Series. - 1382-4309 .- 2215-1826.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The flow unsteadiness generated in a swirl apparatus is investigated ex- perimentally and numerically. The swirl apparatus, shown in figure below, is designed and measured in Timi ̧soara, Romania. The LDA measurements are performed along three survey axes in the test section to provide the character- istics of the swirling flow in the conical diffuser. The swirling flow configuration corresponds to part load operation of a Francis turbine. A series of numerical simulations is undertaken to study a highly swirling turbulent flow generated by rotor-stator interaction in a swirl generator. The purpose is to assess the applicability of different turbulence models in swirling flow with a high level of unsteadiness and a significant production and dissipation of turbulence in the flow away from the wall. Nine turbulence models are compared: four high- Reynolds number URANS, two low-Reynolds number URANS and three hybrid URANS-LES models. The URANS models are capable of capturing the main unsteady feature of this flow, the so-called helical vortex rope, which is formed by the strong centrifugal force and an on-axis recirculation region. However, the size of the on-axis recirculation region is overestimated by the URANS models. It is shown that a more detailed resolution, which is provided by the hybrid URANS-LES methods, is necessary to capture the turbulence and the coherent structures. The flow contains a strong disintegration of the vortex rope which is predicted well by the hybrid URANS-LES models. The hybrid methods also capture the blade wakes better than the other models, elucidating the wake interaction with the vortex rope. The frequency of the vortex rope is predicted well and the total turbulence (resolved and modeled), suggested by the hybrid method, corresponds reasonably well to the experimental results.
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| 24. |
- Javadi, Ardalan, 1984, et al.
(författare)
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Velocity and pressure fluctuations induced by the precessing helical vortex in a conical diffuser
- 2014
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Ingår i: IOP Conference Series: Earth and Environmental Science. - : IOP Publishing. - 1755-1307 .- 1755-1315. ; 22, s. Art. no. 032009-
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Konferensbidrag (refereegranskat)abstract
- The flow unsteadiness generated in the draft tube cone of hydraulic turbines affects the turbine operation. Therefore, several swirling flow configurations are investigated using a swirling apparatus in order to explore the unsteady phenomena. The swirl apparatus has two parts: the swirl generator and the test section. The swirl generator includes two blade rows being designed such that the exit velocity profile resembles that of a turbine with fixed pitch. The test section includes a divergent part similar to the draft tube cone of a Francis turbine. A new control method based on a magneto rheological brake is used in order to produce several swirling flow configurations. As a result, the investigations are performed for six operating regimes in order to quantify the flow from part load operation, corresponding to runaway speed, to overload operation, corresponding to minimum speed, at constant guide vane opening. The part load operation corresponds to 0.7 times the best efficiency discharge, while the overload operation corresponds to 1.54 times the best efficiency discharge. LDV measurements are performed along three survey axes in the test section. The first survey axis is located just downstream the runner in order to check the velocity field at the swirl generator exit, while the next two survey axes are located at the inlet and at the outlet of the draft tube cone. Two velocity components are simultaneously measured on each survey axis. The measured unsteady velocity components are used to validate the results of unsteady numerical simulations, conducted using the OpenFOAM CFD code. The computational domain covers the entire swirling apparatus, including strouts, guide vanes, runner, and the conical diffuser. A dynamic mesh is used together with sliding GGI interfaces to include the effect of the rotating runner. The Reynolds averaged Navier–Stokes equations coupled with the RNG k–ε turbulence model are utilized to simulate the unsteady turbulent flow throughout the swirl generator.
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| 25. |
- Jouybari, Arash, et al.
(författare)
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Methods comparison for attitude determination of a lightweight buoy by raw data of IMU
- 2019
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Ingår i: Measurement. - : Elsevier. - 0263-2241 .- 1873-412X. ; 135, s. 348-354
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Tidskriftsartikel (refereegranskat)abstract
- Today, one of the most important issues is the determination of instantaneous sea level and distinguishing the Tsunami by floating buoy in the ocean. Usually, gyroscopes are used to measure the angular velocity of a buoy. On the other hand, considering the advancement of various technologies in the field of precise accelerometers, make it possible to use these kinds of sensors for navigation purpose. In this research, stable and optimal methods for determining the orientation of a moving buoy is presented using a combination of the gyroscope, accelerometers, and magnetic sensors data. In order to prove the effectiveness of the proposed methods, the raw data were collected from accelerometers, gyroscopes, and magnetometers of (Xsens MTI-G-700) mounted on a Buoy in coastal waters of Kish Island, Iran. Then, by using the proposed methods, the Euler angles of the buoy are determined, while the Euler angles are derived from the Xsens sensor we are considered as a reference. Based on the results, RMSD for Madgwick algorithm are 0.57° 0.37° and 0.50° for Mahony algorithm are 0.56° 0.37° and 0.50° and finally for Complementary algorithm is 0.63° 0.26° and 2.38° which these values are for roll, pitch, and yaw angles respectively. Thus Mahony algorithm for determining roll and yaw Euler angles is more accurate than other algorithms; however, this differences is negligible compared to the Madgwick algorithm. The Complementary algorithm is less accurate than the other two algorithms, especially for determining the yaw angle of the buoy.
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| 27. |
- Mazaheri, Monir, 1977-, et al.
(författare)
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Older people in disasters
- 2016
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Ingår i: International Journal of Qualitative Methods. - 1609-4069. ; 15:1
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Tidskriftsartikel (refereegranskat)
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| 28. |
- Nilsson, Gisela M A, 1973, et al.
(författare)
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Two different isoforms of osteopontin modulate myelination and axonal integrity
- 2023
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Ingår i: Faseb Bioadvances. - 2573-9832. ; 5:8, s. 336-353
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Tidskriftsartikel (refereegranskat)abstract
- Abnormal myelination underlies the pathology of white matter diseases such as preterm white matter injury and multiple sclerosis. Osteopontin (OPN) has been suggested to play a role in myelination. Murine OPN mRNA is translated into a secreted isoform (sOPN) or an intracellular isoform (iOPN). Whether there is an isoform-specific involvement of OPN in myelination is unknown. Here we generated mouse models that either lacked both OPN isoforms in all cells (OPN-KO) or lacked sOPN systemically but expressed iOPN specifically in oligodendrocytes (OLs-iOPN-KI). Transcriptome analysis of isolated oligodendrocytes from the neonatal brain showed that genes and pathways related to increase of myelination and altered cell cycle control were enriched in the absence of the two OPN isoforms in OPN-KO mice compared to control mice. Accordingly, adult OPN-KO mice showed an increased axonal myelination, as revealed by transmission electron microscopy imaging, and increased expression of myelin-related proteins. In contrast, neonatal oligodendrocytes from OLs-iOPN-KI mice compared to control mice showed differential regulation of genes and pathways related to the increase of cell adhesion, motility, and vasculature development, and the decrease of axonal/neuronal development. OLs-iOPN-KI mice showed abnormal myelin formation in the early phase of myelination in young mice and signs of axonal degeneration in adulthood. These results suggest an OPN isoform-specific involvement, and a possible interplay between the isoforms, in myelination, and axonal integrity. Thus, the two isoforms of OPN need to be separately considered in therapeutic strategies targeting OPN in white matter injury and diseases.
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| 29. |
- Rafati, A. H., et al.
(författare)
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Geometrical modelling of neuronal clustering and development
- 2022
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Ingår i: Heliyon. - : Elsevier BV. - 2405-8440. ; 8:7
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Tidskriftsartikel (refereegranskat)abstract
- The dynamic geometry of neuronal development is an essential concept in theoretical neuroscience. We aimed to design a mathematical model which outlines stepwise in an innovative form and designed to model neuronal development geometrically and modelling spatially the neuronal-electrical field interaction. We demonstrated flexibility in forming the cell and its nucleus to show neuronal growth from inside to outside that uses a fractal cylinder to generate neurons (pyramidal/sphere) in form of mathematically called 'surface of revolution'. Furthermore, we verified the effect of the adjacent neurons on a free branch from one-side, by modelling a 'normal vector surface' that represented a group of neurons. Our model also indicated how the geometrical shapes and clustering of the neurons can be transformed mathematically in the form of vector field that is equivalent to the neuronal electromagnetic activity/electric flux. We further simulated neuronal-electrical field interaction that was implemented spatially using Van der Pol oscillator and taking Laplacian vector field as it reflects biophysical mechanism of neuronal activity and geometrical change. In brief, our study would be considered a proper platform and inspiring modelling for next more complicated geometrical and electrical constructions.
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| 30. |
- Ravaghi, H, et al.
(författare)
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Role of hospitals in recovery from COVID-19: Reflections from hospital managers and frontliners in the Eastern Mediterranean Region on strengthening hospital resilience
- 2023
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Ingår i: Frontiers in public health. - : Frontiers Media SA. - 2296-2565. ; 10, s. 1073809-
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Tidskriftsartikel (refereegranskat)abstract
- COVID-19 highlighted the critical role that hospitals play throughout the prolonged response and continuous recovery stages of the pandemic. Yet, there is limited evidence related to hospitals in the recovery stage, particularly capturing the perspectives of hospital managers and frontliners in resource-restrained and humanitarian settings.ObjectiveThis paper aims to capture the perspectives of hospital managers and frontliners across the Eastern Mediterranean Region on (1) the role of hospitals in recovering from COVID-19, (2) Hospitals' expectations from public health institutions to enable recovery from COVID-19, (3) the Evaluation of hospital resilience before and through COVID-19, and (4) lessons to strengthen hospital resilience throughout the COVID-19 recovery.MethodsA multi-methods approach, triangulating a scoping review with qualitative findings from 64 semi-structured key-informant interviews and survey responses (n = 252), was used to gain a deeper context-specific understanding. Purposeful sampling with maximum diversity supported by snowballing was used and continued until reaching data saturation. Thematic analysis was conducted using MAXQDA and simple descriptive analysis using Microsoft Excel.FindingsIn recovering from COVID-19, hospital managers noted hospitals' role in health education, risk reduction, and services continuity and expected human resource management, financial and material resource mobilization, better leadership and coordination, and technical support through the provision of updated clinical evidence-based information from their public health institutions. Qualitative findings also indicated that hospital managers attributed considerable changes in hospitals' resilience capacities to the pandemic and suggested that strengthening hospitals' resilience required resilient staff, sustainable finance, and adaptive leadership and management.ConclusionHospitals are the backbone of health systems and a main point of contact for communities during emergencies; strengthening their resilience throughout the various stages of recovery is critical. Hospitals cannot be resilient in silos but rather require an integrated-whole-of-society-approach, inclusive of communities and other health systems actors.
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| 31. |
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| 32. |
- Zelco, Aura, et al.
(författare)
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Type 2 Innate Lymphoid Cells Accumulate in the Brain After Hypoxia-Ischemia but Do Not Contribute to the Development of Preterm Brain Injury.
- 2020
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Ingår i: Frontiers in cellular neuroscience. - : Frontiers Media SA. - 1662-5102. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- The immune system of human and mouse neonates is relatively immature. However, innate lymphoid cells (ILCs), commonly divided into the subsets ILC1, ILC2, and ILC3, are already present in the placenta and other fetal compartments and exhibit higher activity than what is seen in adulthood. Recent reports have suggested the potential role of ILCs, especially ILC2s, in spontaneous preterm labor, which is associated with brain damage and subsequent long-term neurodevelopmental deficits. Therefore, we hypothesized that ILCs, and especially ILC2s, play a role in preterm brain injury.C57Bl/6J mice at postnatal day 6 were subjected to hypoxia-ischemia (HI) insult induced by left carotid artery ligation and subsequent exposure to 10% oxygen in nitrogen. The presence of ILCs and ILC2s in the brain was examined at different time points after HI. The contribution of ILC2s to HI-induced preterm brain damage was explored using a conditionally targeted ILC2-deficient mouse strain (Rorα fl/fl IL7r Cre ), and gray and white-matter injury were evaluated at 7 days post-HI. The inflammatory response in the injured brain was assessed using immunoassays and immunochemistry staining.Significant increases in ILCs and ILC2s were observed at 24 h, 3 days, and 7 days post-HI in the injured brain hemisphere compared with the uninjured hemisphere in wild-type mice. ILC2s in the brain were predominantly located in the meninges of the injured ipsilateral hemispheres after HI but not in the brain parenchyma. Overall, we did not observe changes in cytokine/chemokine levels in the brains of Rorα fl/fl IL7r Cre mice compared with wild type animals apart from IL-13. Gray and white-matter tissue loss in the brain was not affected after HI in Rorα fl/fl IL7r Cre mice. Correspondingly, we did not find any differences in reactive microglia and astrocyte numbers in the brain in Rorα fl/fl IL7r Cre mice compared with wild-type mice following HI insult.After HI, ILCs and ILC2s accumulate in the injured brain hemisphere. However, ILC2s do not contribute to the development of brain damage in this mouse model of preterm brain injury.
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