| 38391. |
- Hanson, Lars A, et al.
(författare)
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The transfer of immunity from mother to child.
- 2003
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Ingår i: Annals of the New York Academy of Sciences. - 0077-8923 .- 1749-6632. ; 987, s. 199-206
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Tidskriftsartikel (refereegranskat)abstract
- The newborn's immune system grows fast from a small size at birth by exposure primarily to the intestinal microflora normally obtained from the mother at and after birth. While building up its immune system, the infant is supported by the transplacental IgG antibodies, which also contain anti-idiotypic antibodies, possibly also actively priming the offspring. The second mode of transfer of immunity occurs via the milk. Numerous major protective components, including secretory IgA (SIgA) antibodies and lactoferrin, are present. The breastfed infant is better protected against numerous common infections than the non-breastfed. Breastfeeding also seems to actively stimulate the infant's immune system by anti-idiotypes, uptake of milk lymphocytes, cytokines, etc. Therefore, the breastfed child continues to be better protected against various infections for some years. Vaccine responses are also often enhanced in breastfed infants. Long-lasting protection against certain immunological diseases such as allergies and celiac disease is also noted.
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| 38392. |
- Hanssen, Katrine Sjaastad, et al.
(författare)
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Dissection and culturing of adult lateral entorhinal cortex layer II neurons from APP/PS1 Alzheimer model mice
- 2023
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Ingår i: Journal of Neuroscience Methods. - : Elsevier. - 0165-0270 .- 1872-678X. ; 390
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Tidskriftsartikel (refereegranskat)abstract
- Background: Primary neuronal cultures enable cell-biological studies of Alzheimer's disease (AD), albeit typically non-neuron-specific. The first cortical neurons affected in AD reside in layer II of the lateralmost part of the entorhinal cortex, and they undergo early accumulation of intracellular amyloid-β, form subsequent tau pathology, and start degenerating pre-symptomatically. These vulnerable entorhinal neurons uniquely express the glycoprotein reelin and provide selective inputs to the hippocampal memory system. Gaining a more direct access to study these neurons is therefore highly relevant.New method: We demonstrate a methodological approach for dissection and long-term culturing of adult lateral entorhinal layer II-neurons from AD-model mice.Results: We maintain adult dissected lateralmost entorhinal layer II-neurons beyond two months in culture. We show that they express neuronal markers, and that they are electrophysiologically active by 15 days in vitro and continuing beyond 2 months.Comparison with existing methods: Primary neurons are typically harvested from embryonic or early postnatal brains because such neurons are easier to culture compared to adult neurons. Methods to culture adult primary neurons have been reported, however, to our knowledge, culturing of adult entorhinal neuron-type specific primary neurons from AD-model animals have not been reported.Conclusions: Our methodological approach offers a window to study initial pathological changes in the AD disease-cascade. This includes the study of proteinopathy, single-neuron changes, and network-level dysfunction.
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| 38393. |
- Hansson, Andreas, et al.
(författare)
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Chlorophyll limitation in plants remodels and balances the photosynthetic apparatus by changing the accumulation of photosystems I and II through two different approaches.
- 2009
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Ingår i: Physiologia Plantarum. - : Wiley. - 0031-9317 .- 1399-3054. ; 135:2, s. 214-228
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Tidskriftsartikel (refereegranskat)abstract
- Arabidopsis plants with a reduced expression of CHL27 (chl27), an enzyme (EC 1.14.13.81) required for the synthesis of Pchlide, are chlorotic and have a Chl a/b ratio two times higher than wild-type (WT). Knockdown plants transformed with a construct constitutively expressing CHL27 recovered regarding Chl level, a/b ratio and 77K fluorescence. A negative correlation was found between total Chl and Chl a/b ratio in the examined plants. The chl27 plants fail to assemble WT amounts of complete PSI and PSII, leading to an elevated PSII/PSI ratio. The PSI remaining in chl27 is fully functional with a quantum yield higher than for WT. Despite a severe reduction of photosystem II antennae protein (LHCII) and an increased proportion of stroma lammella, the chl27 plants are able to perform state transitions. No major differences were found regarding PSII quantum yield, qN and 1 - qp whereas non-photochemical quenching was decreased by a factor two in chl27 plants. The PSII quantum yield for dark-adapted plants and plants given 10 min recovery after high light treatment were similar for both WT and chl27 showing that chl27 plants are not more susceptible to photoinhibition than WT. Taken together the plant manage to acclimate and to balance the two photosystems well even when it is severely limited in Chl. The way to achieve this differs for the two photosystems: regarding PSI a general reduction of core and antenna subunits occurs with no apparent change in the antenna composition; whereas for PSII there is a preferential loss of antenna proteins.
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| 38394. |
- Hansson, Anders, et al.
(författare)
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Normative video head impulse test data in subjects with and without vascular risk factors
- 2021
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Ingår i: European Archives of Oto-Rhino-Laryngology. - : Springer Berlin/Heidelberg. - 0937-4477 .- 1434-4726. ; 278:7, s. 2619-2624
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: There is a paucity of age- and vascular risk factor-stratified video head impulse test (vHIT) vestibulo-ocular reflex (VOR) data in the literature. The aim of this study was to investigate the vHIT VOR properties in healthy subjects of different ages and subjects with vascular risk factors.Methods: This was a prospective observational single-center study at a tertiary referral university hospital in northern Sweden. Healthy participants and subjects with vascular risk factors were investigated with a floor standing external camera vHIT device. Age-stratified mean VOR gain among healthy adults and between group gain and gain asymmetry differences were calculated.Results: We included eighty-eight healthy adults with a mean (range) age of 50 (22-85) years andn = 48 stroke ward patients with vascular risk factors (but without vestibular disease) with a mean (range) age of 74 (42-92) years. The mean VOR gain of horizontal canals decreased at higher ages in healthy subjects (r = - 0.32,p < 0.01,n = 167 canals). The age-stratified mean (SD) VOR gains were < 30 years: 0.98 (0.07), 30-39 years: 0.97 (0.07), 40-49 years: 0.98 (0.06), 50-59 years: 0.99 (0.06), 60-69 years: 0.93 (0.08), >= 70 years: 0.89 (0.15). No consistent differences between healthy subjects and subjects with vascular risk factors were seen except for a trend towards more pronounced gain asymmetries in the latter group.Conclusions: Age, but not vascular risk factors influence VOR gain. Age-adjusted vHIT-measurements may be useful in acute vertigo stroke risk differentiation.
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| 38395. |
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| 38396. |
- Hansson, Alva, et al.
(författare)
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Reduced bronchoalveolar macrophage phagocytosis and cytotoxic effects after controlled short-term exposure to wood smoke in healthy humans
- 2023
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Ingår i: Particle and Fibre Toxicology. - : BioMed Central (BMC). - 1743-8977. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Exposure to wood smoke has been shown to contribute to adverse respiratory health effects including airway infections, but the underlying mechanisms are unclear. A preceding study failed to confirm any acute inflammation or cell influx in bronchial wash (BW) or bronchoalveolar lavage (BAL) 24 h after wood smoke exposure but showed unexpected reductions in leukocyte numbers. The present study was performed to investigate responses at an earlier phase, regarding potential development of acute inflammation, as well as indications of cytotoxicity.Methods: In a double-blind, randomised crossover study, 14 healthy participants were exposed for 2 h to filtered air and diluted wood smoke from incomplete wood log combustion in a common wood stove with a mean particulate matter concentration of 409 µg/m3. Bronchoscopy with BW and BAL was performed 6 h after exposure. Differential cell counts, assessment of DNA-damage and ex vivo analysis of phagocytic function of phagocytosing BAL cells were performed. Wood smoke particles were also collected for in vitro toxicological analyses using bronchial epithelial cells (BEAS-2B) and alveolar type II-like cells (A549).Results: Exposure to wood smoke increased BAL lactate dehydrogenase (LDH) (p = 0.04) and reduced the ex vivo alveolar macrophage phagocytic capacity (p = 0.03) and viability (p = 0.02) vs. filtered air. BAL eosinophil numbers were increased after wood smoke (p = 0.02), while other cell types were unaffected in BW and BAL. In vitro exposure to wood smoke particles confirmed increased DNA-damage, decreased metabolic activity and cell cycle disturbances.Conclusions: Exposure to wood smoke from incomplete combustion did not induce any acute airway inflammatory cell influx at 6 h, apart from eosinophils. However, there were indications of a cytotoxic reaction with increased LDH, reduced cell viability and impaired alveolar macrophage phagocytic capacity. These findings are in accordance with earlier bronchoscopy findings at 24 h and may provide evidence for the increased susceptibility to infections by biomass smoke exposure, reported in population-based studies.
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| 38397. |
- Hansson, Anders, et al.
(författare)
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Semi-autonomous shared control of large-scale manipulator arms
- 2010
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Ingår i: Control Engineering Practice. - : Elsevier. - 0967-0661 .- 1873-6939. ; 18:9, s. 1069-1076
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Tidskriftsartikel (refereegranskat)abstract
- Semi-autonomous operation with shared control between the human operator and control computer has been developed and examinedfor a large-scalemanipulator for gripping and lifting heavy objects in unstructured dynamical environments. The technique hasbeen implemented on a electro-hydraulic actuated crane arm with redundant kinematic structure. Several modes of automation andinteraction were evaluated. Experiments show satisfactory smoothness in the transitions between autonomous, shared and manualcontrol, increased performance in log loading for inexperienced operators while experienced operators reported reduced workload.
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| 38398. |
- Hansson, Anita, et al.
(författare)
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Short- and Long-Term Effects of Child Neuropsychological Assessment With a Collaborative and Therapeutic Approach : A Preliminary Study
- 2016
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Ingår i: Applied neuropsychology. Child. - : Informa UK Limited. - 2162-2965 .- 2162-2973. ; 5:2, s. 97-106
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Tidskriftsartikel (refereegranskat)abstract
- This preliminary study explored if a collaborative and therapeutic approach (CTA) could reduce self-reported psychiatric symptoms (Beck Youth Inventories [BYI]) in children referred for neuropsychological assessment. Participants included 11 children (M-age=12.4 years) receiving CTA, 11 (M-age=12.6 years) receiving parent support, and 9 (M-age=12.3 years) remaining on a waiting list. Contrary to both comparison groups, the CTA group reported fewer psychiatric symptoms on most BYI subscales after intervention, and this decrease was sustained for the Anger and Anxiety subscales at 6-month follow-up. Findings support a potential effectiveness of CTA in the neuropsychological assessment of children in a child psychiatric setting.
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| 38399. |
- Hansson, Annika, 1979-
(författare)
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The effects of plasminogen deficiency on the healing of tympanic membrane perforations
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The healing of tympanic membrane (TM) perforations is a complex wound healing process including inflammation, migration of keratinocytes and tissue remodelling. Most TM perforations in human heal spontaneously, however some perforations become chronic, and the reason to why is still largely unknown. In cutaneous wound healing plasminogen (plg) has been shown to play an important role. Plg is converted into the protease plasmin regulated by two plasminogen activators (PA), urokinase type PA (uPA) and tissue-type PA (tPA). The aim of the present thesis was to evaluate the role of plg in healing of TM perforations, both in vivo and in vitro. The main objectives were to determine the healing capacity of the TM, the involvement of keratinocytes, fibrin(ogen) and inflammatory cells in the healing process. The studies were performed in plg deficient and uPA deficient mice, with littermate wild type (wt) mice as controls It was shown that myringotomies of the TMs in plg deficient mice still remained open 143 days following a perforation. The wound area was characterized by an abundant recruitment and accumulation of inflammatory cells; mainly macrophages and neutrophils, an arrested keratinocyte migration and a fibrin deposition covering the surface of the TM. The TM perforations in the wt mice all healed within 11 days. Interestingly, the myringotomies of the plg deficient mice could be closed by reconstitution with systemic injections of plg, whereas injections of PBS had no affect on the healing. To characterize mechanisms involved in the development of persistent TM perforations in plg deficient mice after a myringotomy the early inflammatory response during the first 48 hours was studied. The recruitment and accumulation of inflammatory cells in the perforated TMs was found to be similar between the plg deficient and the wt mice. Myringotomized TMs in uPA deficient mice healed similar to perforations of wt controls. Neither did the keratinocyte migration nor the occurrence of inflammatory cells differ between these genotypes. In the in vitro experiments TMs from plg deficient and wt mice, were dissected out, perforated and cultured in absence or surplus of plg. A decrease in perforation size was seen in all groups regardless of genotype or amount of plg in the medium. In conclusion, the present studies show: • Plg is essential for the healing of TM perforations in mice. • The altered healing process after a myringotomy in plg deficient mice involves a disturbed keratinocyte migration, a massive deposition of fibrin and an abundant accumulation of inflammatory cells in the wound area. • Plasminogen deficiency does not alter the early inflammatory response, following a myringotomy. • Deficiency of uPA does not influence the healing of TM perforations. • During in vitro conditions healing of TM perforations is initiated irrespectively of genotype of the explant (plg deficient or wt) or supply of plg. The increased knowledge of the involvement of plg in the healing of TM perforations may open therapeutical possibilities in the treatment of chronic TM perforations in humans.
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| 38400. |
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