1. |
- Ahlman, Håkan, 1947, et al.
(författare)
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Clinical management of gastric carcinoid tumors.
- 1994
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Ingår i: Digestion. - 0012-2823. ; 55 Suppl 3, s. 77-85
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Tidskriftsartikel (refereegranskat)abstract
- Four types of gastric carcinoids have been identified: (1) multiple small body-fundus carcinoids associated with chronic atrophic gastritis type A (A-CAG); (2) sporadic solitary lesions without specific pathogenetic background (non-A-CAG); (3) carcinoidosis associated with Zollinger-Ellison/MEN 1 syndrome, and (4) rare tumors, e.g. gastrin cell tumors, neuroendocrine carcinomas and mixed endocrine-exocrine tumors. In a retrospective study of 15 patients with gastric carcinoids (11 A-CAG, 3 non-A-CAG and 1 gastrin cell tumor) over a 10-year period, the histopathological and clinical features were assessed. The A-CAG-type carcinoids were clinically silent with lymph node metastases in 2/11 cases but no hepatic metastases. The non-A-CAG-type carcinoids were malignant with disseminated disease, hormonal symptoms and increased urinary excretion of the main histamine metabolite, MeImAA. Five patients with A-CAG tumors were subjected to antrectomy to remove hypergastrinemia, which is thought to be of pathogenetic importance for these tumors. During the observation period (1.5-8 years) 1 patient developed recurrent tumors, while the other 4 showed persistent argyrophil cell hyperplasia. A prospective treatment protocol of these tumors is suggested with endoscopic removal of less numerous, small lesions as first-step therapy, followed by antrectomy at recurrence. Larger lesions should be excised in combination with antrectomy. Gastrectomy is reserved for the rare cases of invasive tumors with lymph node metastases. As evident from the outcome of patients with non-A-CAG tumors radical surgery should be performed whenever practicable.
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2. |
- Ahlman, Håkan, 1947, et al.
(författare)
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The relevance of somatostatin receptors in thyroid neoplasia.
- 1997
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Ingår i: The Yale journal of biology and medicine. - 0044-0086. ; 70:5-6, s. 523-33
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- 111In-octreotide scintigraphy in patients with persistent medullary thyroid carcinoma (MTC) visualized tumors in about half of the surgically explored sites. Tumor visualization correlated with rapid tumor growth and large tumor volume as judged from calcitonin levels. The 111In concentration ratio between tumor (T) and blood (B) in surgically excised lymph node metastases of MTC showed a large variation, with low values for microscopic and high values for macroscopic metastases in individual patients. Three cases of MTC, Hürthle cell adenoma and papillary thyroid cancer are reported with preoperative scintigraphy, T/B ratios and Northern analyses of the surgical biopsies. Visualization of tumors was possible in the absence of sstr2 (the high affinity receptor for octreotide) with the exception of microscopic tumor growth. T/B values in the patient with Hürthle cell adenoma were similar to those found in the contralateral thyroid lobe with goitre. The relatively high uptake of 111In in benign thyroid conditions probably limits the use of octreotide scintigraphy in the diagnosis of primary tumors. The technique has certain advantages over radioiodine scintigraphy after the surgical treatment of thyroid tumors: no need for withdrawal of thyroxin substitution; a possibility to diagnose metastases of tumors that do not concentrate radioiodine (MTC, Hürthle cell cancer); and complementary information about metastatic sites of non-medullary thyroid cancer (papillary and follicular tumors).
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3. |
- Amiri-Mosavi, A, et al.
(författare)
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Expression of cholecystokinin-B/gastrin receptors in medullary thyroid cancer.
- 1999
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Ingår i: The European journal of surgery = Acta chirurgica. - : Oxford University Press (OUP). - 1102-4151. ; 165:7, s. 628-31
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Tidskriftsartikel (refereegranskat)abstract
- To characterise the cholecystokinin (CCK) receptor subtypes in medullary thyroid cancer by measuring the expression of CCK-A and CCK-B/gastrin receptor mRNA.
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4. |
- Cornelissen, M. J., et al.
(författare)
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Perinatal complications in patients with unisutural craniosynostosis: An international multicentre retrospective cohort study
- 2017
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Ingår i: Journal of Cranio-Maxillofacial Surgery. - : Elsevier BV. - 1010-5182. ; 45:11, s. 1809-1814
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Craniosynostosis may lead to hampered fetal head molding and birth complications. To study the interaction between single suture craniosynostosis and delivery complications, an international, multicentre, retrospective cohort study was performed. Materials and methods: All infants born between 2006 and 2012 in the Netherlands and Sweden with sagittal or metopic suture synostosis were included. All births were included as a reference population. The primary outcome measure was rate of medically assisted labor. The secondary outcomes included method of conception, term of birth and fetal position. Results: We included 152 trigonocephaly patients, 272 scaphocephaly patients and 1.954.141 controls. A higher rate of assisted reproductive technology (ART) was found in patients with trigonocephaly (13%) and scaphocephaly (7%) compared to controls (3%, p < 0.001). Scaphocephaly resulted in more postterm births (8% vs 4%, p < 0.001). Trigonocephaly patients showed more preterm births (11% vs 6%, p < 0.001), breech position was more frequent (10% vs 4%, p = 0.003) and labor was more often induced. Rate of assisted delivery, including cesarean section, was significantly higher in both patient groups. Conclusions: Scaphocephaly leads to more postterm births and an increased rate of cesarean sections. Trigonocephaly is related to ART, and in addition higher rates of breech position and cesarean section are found. Prenatal detection of single suture craniosynostosis could improve perinatal care. (C) 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
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5. |
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6. |
- Jansson, Svante, 1948, et al.
(författare)
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Treatment of bilateral pheochromocytoma and adrenal medullary hyperplasia.
- 2006
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Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923. ; 1073, s. 429-35
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Tidskriftsartikel (refereegranskat)abstract
- The risk for bilateral tumors and long-term outcome after conservative cortical-sparing adrenal surgery was studied in a consecutive single-center series. One hundred fifty-four patients were operated on (1950-2004) for pheochromocytoma (PC=137), or abdominal paraganglioma (PG=17). Twenty had MEN 2 (16 MEN 2A; 4 MEN 2B), 15 von Recklinghausen's disease (VRD), and 1 von Hippel-Lindau (VHL) disease. Twelve patients had, or developed, bilateral adrenal medullary tumors; four with MEN 2A, four with MEN 2B, three with VRD, and one with probably hereditary PC associated with brain tumors/meningioma. Two patients with MEN 2B and one with MEN 2A with had bilateral adrenalectomy (adx). Three VRD patients, two MEN 2B and one MEN 2A patients had cortical-sparing surgery. Two patients were operated on unilaterally, but developed small contralateral tumors; one of these (MEN 2A) had a second asymptomatic PC diagnosed at an older age, so surgery was withheld; the other patient (hereditary PC syndrome) had a small contralateral PC diagnosed at autopsy 9 years later. Only three of nine patients with bilateral operations needed corticosteroid replacement after surgery. Four of six patients died of associated tumors (MTC and meningioma). The mean follow-up was 13 (1-25) years. Twelve MEN 2A patients with unilateral adx have been followed up for 20 (4-36) years without developing a second PC. Cortical-sparing adrenal surgery can safely be performed in the majority of patients with bilateral PC. On the basis of our long-term experience of MEN 2A we perform contralateral adrenal resection only if a second PC is confirmed. Five patients underwent adrenal exploration because of clinical and biochemical findings compatible with PC. Four had asymmetrical positive MIBG scans. They all underwent unilateral adx and diffuse medullary hyperplasia was confirmed (medullary weight estimated morphometrically to 1.0-3.4 g vs. normal weight 0.3-0.5 g in matched controls). These patients have been followed for 19 (5-27) years with normal clinical and biochemical findings. In this rare condition removal of the largest adrenal seems adequate.
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7. |
- Kölby, David, 1993, et al.
(författare)
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Craniotomy of the Fused Sagittal Suture Over the Superior Sagittal Sinus Is a Safe Procedure
- 2017
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Ingår i: Journal of Craniofacial Surgery. - : Ovid Technologies (Wolters Kluwer Health). - 1049-2275. ; 28:3, s. 666-669
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Spring-assisted cranioplasty to correct sagittal synostosis is based on midline craniotomy through the closed sagittal suture, over the superior sagittal sinus (SSS). The aim of the present study was to evaluate the perioperative safety of this technique. Materials and Methods: This is a retrospective study of all patients operated with median craniotomy and springs from 1998 to the end of 2015. For comparison, all Pi-plasties performed during the same time interval were also evaluated. The safety measures were evaluated based on incidence of damage to SSS, incidence of dural tears, perioperative blood loss, operative time, and hospital stay. Results: In the group that had undergone midline craniotomy combined with springs (n = 225), 4 perioperative damages to SSS and 1 dural tear were seen. The perioperative blood loss was 62.8 +/- 65.3mL (mean +/- standard deviation). The operative time was 67.9 +/- 21.5 minutes and the hospital stay was 4.8 +/- 1.1 days. In the group that had undergone pi-plasty (n = 105), no damages to SSS but 3 dural tears were seen. The perioperative blood loss was 352.8 +/- 174.4 mL. The operative time was 126.0 +/- 31.7 minutes and the hospital stay was 7.1 +/- 1.4 days. Conclusion: Craniotomy SSS in sagittal synostosis is a safe procedure with low morbidity in terms of damage to the SSS. Midline craniotomy combined with springs has significantly lower preoperative blood loss, operative time, and hospital stay (P < 0.001 for all) compared to pi-plasty.
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8. |
- Kölby, Lars, 1963, et al.
(författare)
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Somatostatin receptor subtypes, octreotide scintigraphy, and clinical response to octreotide treatment in patients with neuroendocrine tumors.
- 1998
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Ingår i: World journal of surgery. - 0364-2313. ; 22:7, s. 679-83
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Tidskriftsartikel (refereegranskat)abstract
- Several types of neuroendocrine tumor express high numbers of somatostatin receptors (sstr). We have compared the expression of sstr subtypes with the outcome of octreotide scintigraphy in patients with carcinoids and medullary thyroid carcinoma (MTC) in comparison with Hürthle cell tumors. The effect of sstr activation (octreotide treatment) on tumor markers was also studied in patients with disseminated carcinoid tumors. Six patients with carcinoid tumors (four midgut and two foregut), and three patients with thyroid tumors (one MTC, one Hürthle cell carcinoma, and one Hürthle cell adenoma) were studied. Octreotide scintigraphy visualized tumor sites in all nine patients. Macroscopic tumor was verified at these sites at subsequent surgical exploration. Using Northern blotting and subtype-specific riboprobes, sstr could be detected in all tumors examined. All five sstr subtypes were detected in most of the carcinoid tumors. All six carcinoids expressed sstr2. This was in contrast to the findings for the thyroid tumors analyzed, which also expressed several sstr subtypes but in some cases lacked expression of sstr2. This was also the case for normal thyroid tissue. Clinically, octreotide treatment of the patients with midgut carcinoid tumors resulted in palliation of hormonal symptoms accompanied by a significant reduction of urinary 5-HIAA levels (28-71%). These results indicate that carcinoid tumors frequently express all five sstr subtypes. The thyroid tumors also expressed multiple sstr but could lack expression of sstr2. Nevertheless, these tumors were visualized by octreotide scintigraphy, indicating that sstr2 expression is not a prerequisite for tumor imaging.
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9. |
- Paganini, Anna, 1979, et al.
(författare)
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In search of a single standardised system for reporting complications in craniofacial surgery: a comparison of three different classifications.
- 2019
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Ingår i: Journal of plastic surgery and hand surgery. - 2000-6764. ; 59:6, s. 321-7
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Tidskriftsartikel (refereegranskat)abstract
- Comparing complication rates between centres is difficult due to the lack of unanimous criteria regarding what adverse events should be defined as complications and how these events should be compiled. This study analysed all adverse events in a cohort of craniofacial (CF) operations over a 10-year period and applied three different scales (Clavien-Dindo, Leeds and Oxford) for systematic comparison. A total of 1023 consecutive CF procedures in 641 patients was identified. The Clavien-Dindo scale captured 74 complications in 74 procedures (7.2%), whereas the Leeds and Oxford scales captured 163 complications in 134 procedures (13.1%) and 85 complications in 83 procedures (8.1%), respectively. The Clavien-Dindo scale appeared less suitable for CF surgery, because it is predominantly adapted to severe complications and also regards blood transfusion as a complication. The Leeds scale provided a detailed picture of all complications, as well as minor events, whereas the Oxford scale captured all major complications well but applied less accurate definitions for the minor events. Our findings contribute to the benchmarking of complications between CF centres and suggest that both the Leeds and the Oxford scale appear relevant, depending on the emphasis required for major and minor complications and inter-centre audits, respectively.
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10. |
- Tisell, Lars-Eric, 1931, et al.
(författare)
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Expression of somatostatin receptors in oncocytic (Hürthle cell) neoplasia of the thyroid.
- 1999
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Ingår i: British journal of cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 79:9-10, s. 1579-82
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Tidskriftsartikel (refereegranskat)abstract
- Ten consecutive patients with Hürthle cell lesions of the thyroid (nodule/adenoma/carcinoma) were studied by (111)In-DTPA-D-Phe1-octreotide scintigraphy. Octreotide scintigraphy localized the primary Hürthle cell tumour in eight patients as distinct areas of increased uptake of radionuclide. Two patients with Hürthle cell carcinoma, previously thyroidectomized, had their metastases visualized by octreotide scintigraphy. Northern analyses showed expression of multiple somatostain receptor subtypes. Visualization of the Hürthle cell tumour may be due to a higher expression of somatostatin receptors in the lesions than in surrounding normal thyroid tissue. The tissue/blood (111)In concentration ratios for tumour samples from five patients showed clearly higher values than observed for normal connective tissue, muscle or lymph nodes. A relatively high uptake of (111)In was also observed in goiter tissue, which may lead to misinterpretations. The main indication for octreotide scintigraphy in patients with Hürthle cell carcinoma is suspicion of metastatic disease.
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11. |
- Wängberg, Bo, 1953, et al.
(författare)
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Somatostatin Receptors in the Diagnosis and Therapy of Neuroendocrine Tumor.
- 1997
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Ingår i: The oncologist. - 1549-490X. ; 2:1, s. 50-58
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Tidskriftsartikel (refereegranskat)abstract
- The expression of somatostatin receptors in neuroendocrine tumors has facilitated the diagnosis and surgical treatment of patients with these tumors. After injection of a radiolabeled long-acting somatostatin analog, (111)In-octreotide, scintigraphic tumor imaging can ben performed as well as intraoperative tumor localization. During localization studies very high (111)In concentration values were found in tumor tissues versus normal tissues, especially in carcinoid tumors and endocrine pancreatic tumors. Studies on such tumors in cell culture further indicated internalization of (111)In into tumor cells, which is a prerequisite for a radiobiological effect from short range Auger and conversion electrons. Attempts to systemic radionuclide therapy via somatostatin receptors in patients with neuroendocrine tumors have been initiated.
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12. |
- Amoroso, Matteo, 1984, et al.
(författare)
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Functional and morphological studies of in vivo vascularization of 3D-bioprinted human fat grafts
- 2021
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Ingår i: Bioprinting. - : Elsevier BV. - 2405-8866. ; 23
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Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional (3D) bioprinting offers the ability to design and biofabricate 3D structures based on autologous fat; however, the lack of vascularization in larger 3D-bioprinted constructs represents a limiting factor that hampers translation of this technology from bench to bedside. 3D bioprinting using microfractured fat mixed with nanocellulose–alginate hydrogel can promote vascularization through connections of fragments of vessels included in the fat. In this study, we determined the perfusion and diffusion characteristics of 3D-bioprinted fat constructs using magnetic resonance imaging (MRI) and assessed correlations between perfusion and angiogenesis within the printed constructs. Microfractured human fat from liposuction was printed with tunicate nanocellulose–alginate hydrogel, followed by transplantation of the constructs (10 × 10 × 3 mm) into nude mice that underwent longitudinal MRI for up to 99 days. Confirmation of vascularization was undertaken using immunohistochemical and histologic analyses. Before implantation, the constructs contained abundant fat tissue and fragments of human blood vessels (CD31+ and Ku80+), with subsequent in vivo MRI analysis following transplantation indicating low perfusion and suggesting their continued survival mainly by diffusion. Additionally, we observed a high diffusion coefficient (~2 × 10−3 mm2/s) that was preserved throughout the observation period. Following explantation, evaluation revealed that the constructs displayed preserved histology along with a mixture of human (Ku80+) and murine (Ku80−) erythrocyte-containing vessels. These results demonstrated successful interconnection of blood-vessel fragments from microfractured human fat via angiogenesis to form a vascular network with the host circulation, thereby confirming vascularization of the 3D-bioprinted fat constructs.
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13. |
- Amoroso, Matteo, 1984, et al.
(författare)
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The effect of hemodilution on free flap survival: A systematic review of clinical andexperimental studies.
- 2020
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Ingår i: Clinical hemorheology and microcirculation. - 1875-8622. ; 75:4, s. 457-466
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Forskningsöversikt (refereegranskat)abstract
- Acute normovolemic hemodilution (ANH) has been proposed as a microsurgical technique to improve blood flow in free flaps.Here, we present the first systematic review of clinical and experimental studies on the effect of ANH.We performed a systematic literature search of PubMed, Medline, the Cochrane Library, Google Scholar, and ClinicalTrials.gov using search strategies and a review process in agreement with the PRISMA statement and the Cochrane Handbook for systematic reviews of interventions. PICO criteria were defined before bibliometric processing of the retrieved articles, which were analyzed with the SYRCLE RoB tool for risk of bias and the GRADE scale for level of evidence.We retrieved 74 articles from the literature search, and after processing according to PICO criteria, only four articles remained, all of which were experimental. The rating for risk of bias was uncertain according to SYRCLE RoB results, and the level of evidence was low according to GRADE evaluation.There is no clinical evidence for the effect of ANH on microcirculation in free flaps, and experimental studies provide weak evidence supporting the use of hemodilution in reconstructive microsurgery.
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14. |
- Andersson, Mattias K, 1979, et al.
(författare)
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Clinical, genetic and experimental studies of the Brooke-Spiegler (CYLD) skin tumor syndrome
- 2019
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Ingår i: Journal of Plastic Surgery and Hand Surgery. - : Medical Journals Sweden AB. - 2000-656X .- 2000-6764. ; 53:2, s. 71-75
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Tidskriftsartikel (refereegranskat)abstract
- Brooke-Spiegler syndrome (BSS; a.k.a. tuban tumor syndrome) is an autosomal dominant inherited skin disorder caused by germline mutations in the CYLD tumor suppressor gene. BSS is characterized by multiple skin adnexal tumors, mainly cylindromas and spiradenomas on the head and neck. The tumors are often severely disfiguring and require repeated surgical interventions. Here, we describe a four-generation BSS-family with a novel germline c.1613_1614delGC CYLD mutation that introduces a premature STOP codon predicted to result in a truncated, inactivated CYLD protein. In addition, we present a pilot study describing establishment of the first patient-derived xenografts (PDXs) from cutaneous CYLD-defective cylindromas. Fresh tumor tissues from cylindromas were transplanted into immunocompromised mice to generate PDXs. One xenograft showed progressive tumor growth after 3 months whereas the others remained unchanged in size during the 6 months study period. Histopathological and immunohistochemical analyses of the PDXs revealed that they recapitulate the histological and molecular features of their respective primary tumors, including expression of NTRK3 and the oncogenic driver MYB. In summary, we present the first preclinical BSS-model that morphologically and genetically recapitulates human CYLD-defective cylindromas. This model will be useful for preclinical therapeutic drug testing and for further studies of the molecular pathogenesis of inherited cylindromas.
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15. |
- Apelgren, Peter, et al.
(författare)
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Biomaterial and biocompatibility evaluation of tunicate nanocellulose for tissue engineering.
- 2022
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Ingår i: Biomaterials advances. - : Elsevier BV. - 2772-9508. ; 137
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Tidskriftsartikel (refereegranskat)abstract
- Extracellular matrix fibril components, such as collagen, are crucial for the structural properties of several tissues and organs. Tunicate-derived cellulose nanofibrils (TNC) combined with living cells could become the next gold standard for cartilage and soft-tissue repair, as TNC fibrils present similar dimensions to collagen, feasible industrial production, and chemically straightforward and cost-efficient extraction procedures. In this study, we characterized the physical properties of TNC derived from aquaculture production in Norwegian fjords and evaluated its biocompatibility regarding induction of an inflammatory response and foreign-body reactions in a Wistar rat model. Additionally, histologic and immunohistochemical analyses were performed for comparison with expanded polytetrafluoroethylene (ePTFE) as a control. The average length of the TNC as determined by atomic force microscopy was tunable from 3μm to 2.4μm via selection of a various number of passages through a microfluidizer, and rheologic analysis showed that the TNC hydrogels were highly shear-thinning and with a viscosity dependent on fibril length and concentration. As a bioink, TNC exhibited excellent rheological and printability properties, with constructs capable of being printed with high resolution and fidelity. We found that post-print cross-linking with alginate stabilized the construct shape and texture, which increased its ease of handling during surgery. Moreover, after 30days in vivo, the constructs showed a highly-preserved shape and fidelity of the grid holes, with these characteristics preserved after 90days and with no signs of necrosis, infection, acute inflammation, invasion of neutrophil granulocytes, or extensive fibrosis. Furthermore, we observed a moderate foreign-body reaction involving macrophages, lymphocytes, and giant cells in both the TNC constructs and PTFE controls, although TNC was considered a non-irritant biomaterial according to ISO 10993-6 as compared with ePTFE. These findings represent a milestone for future clinical application of TNC scaffolds for tissue repair. One sentence summary: In this study, the mechanical properties of tunicate nanocellulose are superior to nanocellulose extracted from other sources, and the biocompatibility is comparable to that of ePTFE.
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16. |
- Apelgren, Peter, et al.
(författare)
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Chondrocytes and stem cells in 3D-bioprinted structures create human cartilage in vivo.
- 2017
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 12:12
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Tidskriftsartikel (refereegranskat)abstract
- Cartilage repair and replacement is a major challenge in plastic reconstructive surgery. The development of a process capable of creating a patient-specific cartilage framework would be a major breakthrough. Here, we described methods for creating human cartilage in vivo and quantitatively assessing the proliferative capacity and cartilage-formation ability in mono- and co-cultures of human chondrocytes and human mesenchymal stem cells in a three-dimensional (3D)-bioprinted hydrogel scaffold. The 3D-bioprinted constructs (5 × 5 × 1.2 mm) were produced using nanofibrillated cellulose and alginate in combination with human chondrocytes and human mesenchymal stem cells using a 3D-extrusion bioprinter. Immediately following bioprinting, the constructs were implanted subcutaneously on the back of 48 nude mice and explanted after 30 and 60 days, respectively, for morphological and immunohistochemical examination. During explantation, the constructs were easy to handle, and the majority had retained their macroscopic grid appearance. Constructs consisting of human nasal chondrocytes showed good proliferation ability, with 17.2% of the surface areas covered with proliferating chondrocytes after 60 days. In constructs comprising a mixture of chondrocytes and stem cells, an additional proliferative effect was observed involving chondrocyte production of glycosaminoglycans and type 2 collagen. This clinically highly relevant study revealed 3D bioprinting as a promising technology for the creation of human cartilage.
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17. |
- Apelgren, Peter, et al.
(författare)
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In Vivo Human Cartilage Formation in Three-Dimensional Bioprinted Constructs with a Novel Bacterial Nanocellulose Bioink
- 2019
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Ingår i: Acs Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:5, s. 2482-2490
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Tidskriftsartikel (refereegranskat)abstract
- Bacterial nanocellulose (BNC) is a 3D network of nanofibrils exhibiting excellent biocompatibility. Here, we present the aqueous counter collision (ACC) method of BNC disassembly to create bioink with suitable properties for cartilage-specific 3D-bioprinting. BNC was disentangled by ACC, and fibril characteristics were analyzed. Bioink printing fidelity and shear-thinning properties were evaluated. Cell-laden bioprinted grid constructs (5 X 5 X 1 mm(3)) containing human nasal chondrocytes (10 M mL(-1)) were implanted in nude mice and explanted after 30 and 60 days. Both ACC and hydrolysis resulted in significantly reduced fiber lengths, with ACC resulting in longer fibrils and fewer negative charges relative to hydrolysis. Moreover, ACC-BNC bioink showed outstanding printability, postprinting mechanical stability, and structural integrity. In vivo, cell-laden structures were rapidly integrated, maintained structural integrity, and showed chondrocyte proliferation, with 32.8 +/- 13.8 cells per mm(2) observed after 30 days and 85.6 +/- 30.0 cells per mm(2) at day 60 (p = 0.002). Furthermore, a full-thickness skin graft was attached and integrated completely on top of the 3D-bioprinted construct. The novel ACC disentanglement technique makes BNC biomaterial highly suitable for 3D-bioprinting and clinical translation, suggesting cell-laden 3D-bioprinted ACC-BNC as a promising solution for cartilage repair.
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18. |
- Apelgren, Peter, et al.
(författare)
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Long-term in vivo integrity and safety of3D-bioprinted cartilaginous constructs
- 2021
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Ingår i: Journal of Biomedical Materials Research Part B-Applied Biomaterials. - : Wiley. - 1552-4973 .- 1552-4981. ; 109:1, s. 126-136
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Tidskriftsartikel (refereegranskat)abstract
- Long-term stability and biological safety are crucial for translation of 3D-bioprinting technology into clinical applications. Here, we addressed the long-term safety and stability issues associated with 3D-bioprinted constructs comprising a cellulose scaffold and human cells (chondrocytes and stem cells) over a period of 10 months in nude mice. Our findings showed that increasing unconfined compression strength over time significantly improved the mechanical stability of the cell-containing constructs relative to cell-free scaffolds. Additionally, the cell-free constructs exhibited a mean compressive stress and stiffness (compressive modulus) of 0.04 +/- 0.05 MPa and 0.14 +/- 0.18 MPa, respectively, whereas these values for the cell-containing constructs were 0.11 +/- 0.08 MPa (p= .019) and 0.53 +/- 0.59 MPa (p= .012), respectively. Moreover, histomorphologic analysis revealed that cartilage formed from the cell-containing constructs harbored an abundance of proliferating chondrocytes in clusters, and after 10 months, resembled native cartilage. Furthermore, extension of the experiment over the complete lifecycle of the animal model revealed no signs of ossification, fibrosis, necrosis, or implant-related tumor development in the 3D-bioprinted constructs. These findings confirm the in vivo biological safety and mechanical stability of 3D-bioprinted cartilaginous tissues and support their potential translation into clinical applications.
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19. |
- Apelgren, Peter, et al.
(författare)
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Skin Grafting on 3D Bioprinted Cartilage Constructs In Vivo
- 2018
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Ingår i: Plastic and Reconstructive Surgery-Global Open. - : Ovid Technologies (Wolters Kluwer Health). - 2169-7574. ; 6:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Three-dimensional (3D) bioprinting of cartilage is a promising new technique. To produce, for example, an auricle with good shape, the printed cartilage needs to be covered with skin that can grow on the surface of the construct. Our primary question was to analyze if an integrated 3D bioprinted cartilage structure is a tissue that can serve as a bed for a full-thickness skin graft. Methods: 3D bioprinted constructs (10x10x1.2mm) were printed using nanofibrillated cellulose/alginate bioink mixed with mesenchymal stem cells and adult chondrocytes and implanted subcutaneously in 21 nude mice. Results: After 45 days, a full-thickness skin allograft was transplanted onto the constructs and the grafted construct again enclosed subcutaneously. Group 1 was sacrificed on day 60, whereas group 2, instead, had their skin-bearing construct uncovered on day 60 and were sacrificed on day 75 and the explants were analyzed morphologically. The skin transplants integrated well with the 3D bioprinted constructs. A tight connection between the fibrous, vascularized capsule surrounding the 3D bioprinted constructs and the skin graft were observed. The skin grafts survived the uncovering and exposure to the environment. Conclusions: A 3D bioprinted cartilage that has been allowed to integrate in vivo is a sufficient base for a full-thickness skin graft. This finding accentuates the clinical potential of 3D bioprinting for reconstructive purposes.
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20. |
- Apelgren, Peter, et al.
(författare)
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Vascularization of tissue engineered cartilage-Sequential in vivo MRI display functional blood circulation
- 2021
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Ingår i: Biomaterials. - : Elsevier BV. - 0142-9612 .- 1878-5905. ; 276
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Tidskriftsartikel (refereegranskat)abstract
- Establishing functional circulation in bioengineered tissue after implantation is vital for the delivery of oxygen and nutrients to the cells. Native cartilage is avascular and thrives on diffusion, which in turn depends on proximity to circulation. Here, we investigate whether a gridded three-dimensional (3D) bioprinted construct would allow ingrowth of blood vessels and thus prove a functional concept for vascularization of bioengineered tissue. Twenty 10 x 10 x 3-mm 3Dbioprinted nanocellulose constructs containing human nasal chondrocytes or cell-free controls were subcutaneously implanted in 20 nude mice. Over the next 3 months, the mice were sequentially imaged with a 7 T small-animal MRI system, and the diffusion and perfusion parameters were analyzed. The chondrocytes survived and proliferated, and the shape of the constructs was well preserved. The diffusion coefficient was high and well preserved over time. The perfusion and diffusion patterns shown by MRI suggested that blood vessels develop over time in the 3D bioprinted constructs; the vessels were confirmed by histology and immunohistochemistry. We conclude that 3D bioprinted tissue with a gridded structure allows ingrowth of blood vessels and has the potential to be vascularized from the host. This is an essential step to take bioengineered tissue from the bench to clinical practice.
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21. |
- Baranowska Körberg, Izabella, et al.
(författare)
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A progressive and complex clinical course in two family members with ERF-related craniosynostosis: a case report
- 2020
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Ingår i: BMC Medical Genetics. - : Springer Science and Business Media LLC. - 1471-2350. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- Background ERF-related craniosynostosis are a rare, complex, premature trisutural fusion associated with a broad spectrum of clinical features and heterogeneous aetiology. Here we describe two cases with the same pathogenic variant and a detailed description of their clinical course. Case presentation Two subjects; a boy with a BLSS requiring repeated skull expansions and his mother who had been operated once for sagittal synostosis. Both developed intracranial hypertension at some point during the course, which was for both verified by formal invasive intracranial pressure monitoring. Exome sequencing revealed a pathogenic truncating frame shift variant in the ERF gene. Conclusions Here we describe a boy and his mother with different craniosynostosis patterns, but both with verified intracranial hypertension and heterozygosity for a truncating variant of ERF c.1201_1202delAA (p.Lys401Glufs*10). Our work provides supplementary evidence in support of previous phenotypic descriptions of ERF-related craniosynostosis, particularly late presentation, an evolving synostotic pattern and variable expressivity even among affected family members.
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22. |
- Bernhardt, Peter, 1966, et al.
(författare)
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A novel quantitative image-based method for evaluating cranial symmetry and its usefulness in patients undergoing surgery for unicoronal synostosis.
- 2013
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Ingår i: The Journal of craniofacial surgery. - 1536-3732. ; 24:1, s. 166-9
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Tidskriftsartikel (refereegranskat)abstract
- Background: Unicoronal synostosis presents with cranial asymmetry. Fixed points are difficult to identify; surgical results are therefore difficult to evaluate. The aim of this study was to develop a computer-based method for evaluation of forehead symmetry to enable evaluation of surgical results in unicoronal synostosis. Methods: The MATLAB tool was programmed to segment computed tomographic images, leaving the outermost contour. Cephalometric images were segmented manually due to lower contrast. A center-point (O) and an end-point were manually defined in the midline of the forehead and at the nonfused coronal suture, respectively. The program then found a point (p) on the fused side, at the same distance from the O as the end-point. The contours of the left and right side of the forehead were thereafter superimposed, and the position of minimal area mismatch of the sides was identified. To correct for growth between preoperative images and follow-up, the number of mismatching pixels was related to the area outlined by the contour of the forehead, the end-point and p. Two quantities, the relative symmetry change and the absolute symmetry change, were defined and evaluated by repeated measurements on spherical and elliptical phantoms and 15 patients. Results: Measurements with the MATLAB program were reliable with an SD of 0.26% to 5.39% for the expected range of differences. The SD was lower for measurements on computed tomographic images than for measurements on cephalometric images. The SD was also lower in patients with large surgical improvement than in patients with little improvement. The results support the use of relative symmetry change to evaluate surgical results. Conclusions: Our new computer-based method is capable of measuring forehead symmetry with good precision. This method can be used for systematic evaluation of surgical outcome for unicoronal synostosis and other asymmetric skull deformities.
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23. |
- Bernhardt, Peter, 1966, et al.
(författare)
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Effects of treatment with (177)Lu-DOTA-Tyr(3)-octreotate on uptake of subsequent injection in carcinoid-bearing nude mice.
- 2007
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Ingår i: Cancer biotherapy & radiopharmaceuticals. - : Mary Ann Liebert Inc. - 1084-9785 .- 1557-8852. ; 22:5, s. 644-53
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of this study was to analyze the effect therapeutic injections of (177)Lu-DOTA(0)-Tyr(3)]-octreotate (DOTATATE) had on the tumor uptake of a subsequent injection with (111)In-DOTATATE in GOT1-bearing nude mice. METHODS AND MATERIALS: Nude mice, xenografted with the human midgut carcinoid, GOT1, were first intravenously injected with a curative (30 MBq) or a suboptimal (7.5 MBq) amount of (177)Lu-DOTATATE. At various intervals thereafter (4-13 days), a second injection with (111)In-DOTATATE (0.5 MBq) was given. One (1) day after the second injection, the animals were sacrificed, tumor tissues collected, the tumor (111)In and (177)Lu activity concentration determined, and tumor regression/cell density was recorded. RESULTS: In animals given curative amounts, the uptake of (111)In was lower than in untreated animals. On the other hand, a second late injection (3-13 days) after suboptimal amounts resulted in a twofold higher tumor activity concentration versus untreated animals. When the uptake of the curative injection was corrected for tumor cell density, which decreased from 66% to 4% over 2 weeks, an enhanced uptake per tumor cell was observed. The curative and suboptimal amounts resulted in a different uptake and retention of (177)Lu in tumors. The suboptimal amount resulted in a constant activity concentration, while the curative amount resulted in an increased activity concentration over time. CONCLUSIONS: Our results, as presented in this paper, describe how the second injection in a fractionation protocol will be affected by the first therapeutic amount. This new information might be useful in the optimization of radionuclide therapy.
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24. |
- Bevilacqua, Ruggero, et al.
(författare)
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Spring-Assisted Surgery in the Treatment of Complex Craniosynostosis
- 2018
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Ingår i: Journal of Craniofacial Surgery. - 1049-2275. ; 29:4, s. 920-924
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Tidskriftsartikel (refereegranskat)abstract
- Multisutural nonsyndromic craniosynostosis is a rare group of malformations, whose frequency has been reported between 3% and 7% of all craniosynostosis. The clinical diagnosis can be difficult and computed tomography is usually required. Surgical treatment is challenging and staged procedures are performed in up to 80% of patients. The aim of the present study was to determine the reoperation rate and to evaluate the surgical outcomes by measuring intracranial volume (ICV) preoperatively and at follow-up, and comparing it to a control group. Perioperative variables and reoperation rate were recorded. Fifty-one patients presented with a complex pattern of synostosis without a recognizable syndrome (5% of cases of total patients evaluated). Fifteen patients have been treated with spring-assisted surgery, either alone or in combination with a foreheadplasty. The mean follow-up was 6.2 years. The mean preoperative ICV of the patients was smaller, but not significantly, than in the normal population (P = 0.13). Postoperatively, the mean ICV was similar to that of the control group at 1 year (P = 0.92), while at 3 years it was appreciably smaller, although not significantly different (P = 0.06). Five patients (33%) went through a secondary skull expansion for either raised intracranial pressure or cosmetic reasons. Spring-assisted surgery seems to temporarily expand ICV in children with complex synostosis and lower the reoperation rate, thus reducing the need for a second procedure. A longer follow-up would be necessary to further investigate the effects of springs over time.
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25. |
- Brorson, Fredrik, 1965, et al.
(författare)
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Early complications in delayed breast reconstruction: A prospective, randomized study comparing different reconstructive methods in radiated and non-radiated patients
- 2020
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Ingår i: European Journal of Surgical Oncology. - : Elsevier BV. - 0748-7983. ; 46:12, s. 2208-2217
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is little high-quality scientific evidence identifying the best and safest methods for delayed breast reconstruction, with most previous studies retrospective in nature. The primary aim was to compare early complication rates for two different breast-reconstructive methods in radiated and non-radiated patients, using a validated scale. The secondary aim was to identify predictors for complications. Materials and methods: This study represents a clinical, randomized, prospective trial (ClinicalTrials.Gov identifier: NCT03963427), where the patients were divided into two study arms: non-radiated and radiated. In the non-radiated arm, patients were randomized to a one-stage lateral thoracodorsal flap with an implant or two-stage expander reconstruction. In the radiated arm, patients were randomized to a latissimus dorsi reconstruction combined with an implant or deep inferior epigastric artery perforator (DIEP) reconstruction. All adverse events were classified according to Clavien-Dindo and summarization of overall morbidity was performed by calculating the Comprehensive Complication Index score. The study was conducted from 2008 to 2020. Results: The complication frequencies were similar for the two surgical methods within each arm. In the non-radiated arm, risk factors for any complication were any comorbidities, and in the radiated arm, factors were a high body mass index and a contralateral operation. Conclusions: The usage of the Clavien-Dindo scale in reconstructive surgery is feasible, but further validation is needed. In non-radiated patients, the frequencies of short-term complications were similar for lateral thoracodorsal flap and expander reconstruction, whereas in radiated patients, they were similar for DIEP and latissimus dorsi. The complication profile of the methods varied.
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