| 1. |
- Eidsvaag, V. A., et al.
(författare)
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Human and mouse cortical astrocytes differ in aquaporin-4 polarization toward microvessels
- 2017
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Ingår i: Glia. - : Wiley. - 0894-1491. ; 65:6, s. 964-973
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Tidskriftsartikel (refereegranskat)abstract
- Aquaporin-4 (AQP4), the predominant water channel in the brain, is expressed in astrocytes and ependymal cells. In rodents AQP4 is highly polarized to perivascular astrocytic endfeet and loss of AQP4 polarization is associated with disease. The present study was undertaken to compare the expression pattern of AQP4 in human and mouse cortical astrocytes. Cortical tissue specimens were sampled from 11 individuals undergoing neurosurgery wherein brain tissue was removed as part of the procedure, and compared with cortical tissue from 5 adult wild-type mice processed similarly. The tissue samples were immersion-fixed and prepared for AQP4 immunogold electron microscopy, allowing quantitative assessment of AQP4's subcellular distribution. In mouse we found that AQP4 water channels were prominently clustered around vessels, being 5 to 10-fold more abundant in astrocytic endfoot membranes facing the capillary endothelium than in parenchymal astrocytic membranes. In contrast, AQP4 was markedly less polarized in human astrocytes, being only two to three-fold enriched in astrocytic endfoot membranes adjacent to capillaries. The lower degree of AQP4 polarization in human subjects (1/3 of that in mice) was mainly due to higher AQP4 expression in parenchymal astrocytic membranes. We conclude that there are hitherto unrecognized species differences in AQP4 polarization toward microvessels in the cerebral cortex.
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| 2. |
- Hasan-Olive, M. M., et al.
(författare)
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Loss of perivascular aquaporin-4 in idiopathic normal pressure hydrocephalus
- 2019
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Ingår i: Glia. - : Wiley. - 0894-1491. ; 67:1, s. 91-100
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Tidskriftsartikel (refereegranskat)abstract
- Idiopathic normal pressure hydrocephalus (iNPH) is a subtype of dementia that may be successfully treated with cerebrospinal fluid (CSF) diversion. Recently, magnetic resonance imaging (MRI) using a MRI contrast agent as a CSF tracer revealed impaired clearance of the CSF tracer from various brain regions such as the entorhinal cortex of iNPH patients. Hampered clearance of waste solutes, for example, soluble amyloid-beta, may underlie neurodegeneration and dementia in iNPH. The goal of the present study was to explore whether iNPH is associated with altered subcellular distribution of aquaporin-4 (AQP4) water channels, which is reported to facilitate CSF circulation and paravascular glymphatic drainage of metabolites from the brain parenchyma. Cortical brain biopsies of 30 iNPH patients and 12 reference individuals were subjected to AQP4 immunogold cytochemistry. Electron microscopy revealed significantly reduced density of AQP4 water channels in astrocytic endfoot membranes along cortical microvessels in patients with iNPH versus reference subjects. There was a significant positive correlation between density of AQP4 toward endothelial cells (perivascular) and toward parenchyma, but the reduced density of AQP4 toward parenchyma was not significant in iNPH. We conclude that perivascular AQP4 expression is attenuated in iNPH, potentially contributing to impaired glymphatic circulation, and waste clearance, and subsequent neurodegeneration. Hence, restoring normal perivascular AQP4 distribution may emerge as a novel treatment strategy for iNPH.
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| 3. |
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| 4. |
- Falk, Peter, 1962, et al.
(författare)
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Colorectal Cancer Cells Adhere to Traumatized Peritoneal Tissue in Clusters, An Experimental Study.
- 2018
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Ingår i: Journal of investigative surgery. - : Informa UK Limited. - 0894-1939 .- 1521-0553. ; 31:4, s. 349-356
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Tidskriftsartikel (refereegranskat)abstract
- Purpose/Aim: Colorectal malignity is one of the most common forms of cancer. The finding of free intraperitoneal colorectal cancer cells during surgery has been shown to be associated with poor outcome. The aim of this study was to develop an experimental model designed to investigate adhesion of colorectal cancer cells to the peritoneal surface.Two human experimental models were developed, the first using cultured mesothelial cells and the second consisting of an ex vivo model of peritoneal tissue. Both models were subjected to standardized trauma, following which labeled colorectal cancer cells (Colo205) were introduced. Adhesion of tumor cells was monitored using microscopy and detection of fluorochromes.The mesothelial cell layers and peritoneal membranes remained viable in culture medium for several weeks. In our experimental model, the tumor cells added were seen to adhere to the edges of the traumatized area in cluster formations.The use of human peritoneal tissue in an ex vivo model would appear to be a potentially useful tool for the study of interaction between human peritoneal membrane and free tumor cells. Experimental surgical trauma increases the ability of tumor cells to adhere to the peritoneal membrane. This ex vivo model should be useful in future studies on biological interactions between peritoneum and tumor cells in the search for novel forms of peritoneal cancer therapy.
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| 5. |
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| 6. |
- Odelberg, Nina, et al.
(författare)
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The Impact of a Surgical Unit's Structure and Operative Technique on Quality in Two Swedish Rural Hospitals
- 2020
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Ingår i: Journal of investigative surgery. - : Taylor & Francis Group. - 0894-1939 .- 1521-0553. ; 33, s. 924-929
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Laparoscopic cholecystectomy (LC) is a commonly performed surgical procedure with a low complication rate. It is performed either as an acute or as an elective procedure. Most elective LCs are performed on nonlethal diseases and this is why good quality is important. Our study compared the quality of LC in two surgical units in northern Sweden (Sundsvall and ostersund) which use different clinical structures (subspecialised vs. general surgery) and surgical techniques (ultrasound fundus first vs. conventional diathermy). The study aimed to investigate whether these differences affected the quality of outcomes after LC.Materials and methods: This is a registry-based study which included 607 elective LCs from January 2014 to May 2016. There were 286 from Sundsvall and 321 from ostersund. Primary outcomes were operative time and the percentage of day surgeries. The secondary outcome was the presence of postoperative complications within the first 30 days in terms of bile duct injury, bleeding that necessitated reoperation, bile leakage and abscesses treated with drainage and mortality.Results: The time length of surgery was shorter in Sundsvall (mean 48.3 min) compared to ostersund (mean 108.6 min, p < 0.001. The percentage of day care surgeries was 94% in Sundsvall and 23% in ostersund, p < 0.001. Six patients (2.1%) had a complication in Sundsvall compared to seven patients (2.2%) in ostersund, p = 1.00.Conclusion: There is a significant difference between the two hospitals regarding operative time and the percentage of day surgeries. Complication rates in both units were equal and low.
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| 7. |
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| 8. |
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| 9. |
- Oltean, Mihai, 1976
(författare)
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Silybin Against Liver Ischemia-Reperfusion Injury: Something Old, Something New...
- 2018
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Ingår i: Journal of Investigative Surgery. - : Informa UK Limited. - 0894-1939 .- 1521-0553. ; 31:6, s. 521-522
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Tidskriftsartikel (refereegranskat)abstract
- Ischemia reperfusion injury (IRI) is a life threatening condition that may develop after elective liver surgery or liver transplantation. Numerous surgical and pharmacological approaches have shown varying degrees of protection against liver IRI. A group of protective compounds are the flavonoids but their intestinal absorbtion and bioavailability are low and impredictible. In this issue Tsaroucha et al. reports significantly decreased hepatocellular injury, Fas/FasL expression and inhibited HMGB1 release in rats receiving a hydrosoluble, lyophilized complex of SLB and hydroxypropyl-beta-cyclodextrin (SLB-HP-beta-CD) intravenously.
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| 10. |
- Sandblom, G
(författare)
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Inheritance, Environment and Genesis of Inguinal Hernias
- 2022
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Ingår i: Journal of investigative surgery : the official journal of the Academy of Surgical Research. - : Informa UK Limited. - 1521-0553. ; 35:1, s. 212-213
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Tidskriftsartikel (refereegranskat)
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| 11. |
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| 12. |
- Tingstedt, Bobby, et al.
(författare)
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Effect of bioactive polypeptides on leaking large bowel anastomosis and intestines in the rat.
- 2007
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Ingår i: Journal of Investigative Surgery. - : Informa UK Limited. - 0894-1939 .- 1521-0553. ; 20:4, s. 229-235
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Tidskriftsartikel (refereegranskat)abstract
- Anastomotic leakage and postoperative adhesions represent major complications after colorectal surgery. We have previously shown a positive effect on both anastomotic strength and abdominal adhesions by the use of differently charged bioactive polypeptides. The present study aimed to investigate the effect of the same polypeptides on the healing of an insufficient intestinal anastomosis, as well as on accidental intestinal injury, in addition to measuring the preventive effect against the development of abdominal adhesions. An insufficient, and thereby potentially leaking, intestinal anastomosis and punctures of the intestine ("accidental intestinal injury model") were performed in rats. The treatment groups received intraperitoneal administration of poly-L-lysine and poly-L-glutamate, while controls received sodium chloride. Burst pressure, extent of abdominal adhesions, and postoperative complications were analyzed in both experimental models. A significant decrease of adhesions was seen in all animals treated with polypeptides (p < .05). Burst pressure was significantly higher (p < .001) in animals with intestinal perforation as seen on day 1 and then decreasing. A significant decrease in the incidence of peritonitis was also noted early (day 1) in this model (p = .002). The mortality and complications were high in the intestinal anastomosis model, though not affected by treatment with polypeptides. Intraabdominal adhesions were significantly reduced using polypeptides in this study, with no observed effect on other postsurgical complications. There were signs of less infectious complications in polypeptide treated animals. In animals with accidental intestinal injury, a higher burst pressure was noted in treated animals.
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