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51.
Annika Senghaas Thomas Kremer Volker J. Schmidt Leila Harhaus Christoph Hirche Ulrich Kneser Amir K. Bigdeli 《Microsurgery》2019,39(2):174-177
Despite considerable advances in reconstructive surgery, massive abdominal wall defects continue to pose a significant surgical challenge. We report the case of a 72‐year‐old morbidly obese female patient with Clostridium septicum‐related gas gangrene of the abdominal wall. After multidisciplinary treatment and multiple extensive debridements, a massive full‐thickness defect (40 cm × 35 cm) of the right abdominal wall was present. The abdominal contents were covered with a resorbable mesh to prevent evisceration. Finally, the composite defect was successfully reconstructed through a contralateral extended free transverse rectus abdominis myocutaneus (TRAM) flap (50 cm × 38 cm). An arterio‐venous loop to the superficial femoral vessels using the great saphenous vein was necessary to allow the flap to reach the defect. Postoperatively, a minor wound healing disorder of the flap was successfully treated with split skin grafting. Six month after surgery, the patient presented with a completely healed flap coverage area and a small abdominal hernia without the need of further surgical revision. This case illustrates the use of a sliding free TRAM flap for closure of a massive abdominal wall defect. 相似文献
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53.
Generation of full‐thickness skin equivalents using hair follicle‐derived primary human keratinocytes and fibroblasts 下载免费PDF全文
Anna Löwa Annika Vogt Sabine Kaessmeyer Sarah Hedtrich 《Journal of tissue engineering and regenerative medicine》2018,12(4):e2134-e2146
Skin equivalents are increasingly used as human‐based test systems for basic and preclinical research. Most of the established skin equivalents are composed of primary keratinocytes and fibroblasts, isolated either from excised human skin or juvenile foreskin following circumcisions. Although the potential of hair follicle‐derived cells for the generation of skin equivalents has been shown, this approach normally requires microdissections from the scalp for which there is limited subject compliance or ethical approval. In the present study, we report a novel method to isolate and cultivate keratinocytes and fibroblasts from plucked hair follicles that were then used to generate skin equivalents. The procedure is non‐invasive, inflicts little‐pain, and may allow easy access to patient‐derived cells without taking punch biopsies. Overall, minor differences in morphology, ultrastructure, expression of important structural proteins, or barrier function were observed between skin equivalents generated from hair follicle‐derived or interfollicular keratinocytes and fibroblasts. Interestingly, improved basal lamina formation was seen in the hair follicle‐derived skin equivalents. The presented method here allows easy and non‐invasive access to keratinocytes and fibroblasts from plucked hair follicles that may be useful particularly for the generation of skin disease equivalents. 相似文献
54.
Marchini G Hultenby K Nelson A Yektaei-Karin E Ståbi B Lonne-Rahm S Ulfgren AK Brismar H 《Pediatric dermatology》2007,24(5):474-482
Abstract: At birth, commensal microbes penetrate into the skin of the human newborn, eliciting an acute rash, erythema toxicumn neonatorum . Histologically, the rash is characterized by an upregulation of proinflammatory activity and a local recruitment of immunocytes, including macrophages. High mobility group box chromosomal protein 1, a nuclear and cytosolic protein, is also a pro-inflammatory cytokine released by macrophages in response to microbial stimulation. Here, we reasoned that macrophages but also keratinocytes might upregulate this protein in response to the first colonization and that high mobility group box chromosomal protein 1 might play a role as a proinflammatory mediator in the development and progression of erythema toxicum . Punch biopsy specimens from 1-day-old healthy infants, seven with and four without erythema toxicum were analyzed with indirect immunohistochemistry and two different antihigh mobility group box chromosomal protein 1 antibodies, immunofluorescence, nuclear counterstaining, confocal and immunoelectron imaging. We found relocation of nuclear high mobility group box chromosomal protein 1 into the cytoplasm in keratinocytes and macrophages in erythema toxicum. Cytoplasmatic high mobility group box chromosomal protein 1 was also found in melanocytes and did neither co-locate with lysosomal-associated membrane proteins nor with melanosomes. We speculate that terrestrial adaptation triggers the induction of the endogenous "danger signal" high mobility group box chromosomal protein 1 in the skin of the newborn infant, perhaps in response to the first commensal colonization and that this signal may contribute to alert the immune system and promote a protective immune response. 相似文献
55.
In a previous report we demonstrated Epstein-Barr virus expression in cutaneous squamous cell carcinomas from heart transplant recipients. In a comparative study, skin lesions from renal allograft recipients were investigated for the presence of Epstein-Barr virus. Thirty cutaneous squamoproliferative lesions from 10 kidney transplant recipients were examined for Epstein-Barr virus-specific gene expression. The techniques used for detection were polymerase chain reaction, in situ hybridization and immunohistochemistry. Epstein-Barr virus DNA was not detected by polymerase chain reaction in the neoplasias, and only single Epstein-Barr virus-positive carcinoma cells were shown by in situ hybridization in three cases of infiltrative squamous cell carcinomas. Immunohistochemistry for Epstein-Barr virus latent membrane protein 1 showed a negative result in all samples. These findings differ from our earlier investigations of cutaneous squamous cell carcinomas from heart transplant recipients where Epstein-Barr virus expressions were common. This may indicate that the part Epstein-Barr virus plays in the development of post-transplant, cutaneous squamoproliferative disorders is related to type of organ transplantation and/or grade of immunosuppression. 相似文献
56.
Heilig M Zachrisson O Thorsell A Ehnvall A Mottagui-Tabar S Sjögren M Asberg M Ekman R Wahlestedt C Agren H 《Journal of psychiatric research》2004,38(2):113-121
Extensive animal studies suggest neuropeptide Y (NPY) to be involved in coping with a wide range of stressors, and that impaired central NPY signalling could be involved in the pathophysiology of anxiety and depression. Human studies of central NPY levels in depression have, however, been inconclusive. Here, we examined levels of NPY-like immunoreactivity (NPY-LI) in the cerebrospinal fluid (CSF) of medication-free subjects with treatment refractory unipolar depression. Patients were admitted to a research inpatient unit, examined under standardized conditions, and compared with a sample of volunteers in whom psychiatric morbidity was excluded. A robust suppression of NPY levels in patient CSF was found, while other putative CSF markers (monoamine metabolites, somatostatin) did not differ between the groups. We then explored whether this finding might be related to a recently described T1128C coding polymorphism which results in a Leu7-> Pro7 substitution of the signal peptide, and a previously not described T -399C polymorphism in the promoter region of the preproNPY gene. Preliminary evidence was found for an association of both markers with a diagnosis of depression, indicating the possibility of an underlying haplotype influencing the vulnerability for developing depressive illness. Our present findings are in line with an extensive animal literature, and further support the notion that impaired NPY function could contribute to depressive illness. 相似文献
57.
Nils Milman Claus B. Andersen Bo Baslund Annika Loft Martin Iversen 《The clinical respiratory journal》2007,1(2):106-113
Background: Sarcoid granuloma formation involves the orchestration of cytokines and chemokines, which modulate the host's immune response to the antigen stimulus. The release of cytokines enhances expression of the pro‐inflammatory cytokine tumour necrosis factor‐α (TNF), which plays a crucial role in the formation of sarcoid granuloma, being released from T‐lymphocytes and alveolar macrophages. Objective: The aim of this study was to evaluate the effect of infliximab in a case of pulmonary sarcoidosis using a histological approach. Materials and Methods: A 44‐year‐old man with biopsy verified chronic pulmonary sarcoidosis being resistant to treatment with corticosteroids and cell cycle inhibitors. Persisting disease activity was confirmed by declining lung function tests and a positive fluorine‐18‐fluorodeoxyglucose–positron emission tomography scan. The patient was treated with a single course of infliximab 3‐mg/kg body weight; 11 days later, a single lung transplantation was performed. Immunohistological staining with the macrophage marker CD68 was performed on lung tissue and mediastinal lymph node tissue from both the initial diagnostic evaluation (prior to infliximab) as well as from the explanted lung (after infliximab). Results: Biopsy specimens from lung and mediastinal lymph nodes prior to infliximab demonstrated sarcoid granulomas, and staining with CD68 showed dense infiltration by macrophages (epithelioid cells) in the central part of the granulomas. In contrast, biopsies from the explanted lung after infliximab demonstrated acellular sarcoid granulomas with central amorphous masses, and staining with CD68 showed complete absence of macrophages. Conclusions: In this patient, the TNF inhibitor infliximab appeared to induce resolution of sarcoid granulomas starting with disappearance of macrophages probably caused by cell lysis or apoptosis. Please cite this paper as: Milman N, Andersen CB, Baslund B, Loft A and Iversen M. Does tumour necrosis factor‐α inhibitor infliximab induce histological resolution of pulmonary sarcoid granulomas? The Clinical Respiratory Journal 2007; 1:106–113. 相似文献
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59.
Quantitative detection of respiratory Chlamydia pneumoniae infection by real-time PCR 总被引:3,自引:0,他引:3 下载免费PDF全文
Kuoppa Y Boman J Scott L Kumlin U Eriksson I Allard A 《Journal of clinical microbiology》2002,40(6):2273-2274
Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection. 相似文献
60.
Xi-Jing Mao Xing-Mei Zhang Hong-Liang Zhang Hernan Concha Quezada Eilhard Mix Xin Yang Bengt Winblad Abdu Adem Jie Zhu 《Neuroscience letters》2010
Tumor necrosis factor-α (TNF-α) is a pleiotropic pro-inflammatory cytokine with potentially neurodestructive effects and plays a pivotal role in autoimmune demyelinating disease. To address the role of TNF-α in the pathogenesis of experimental autoimmune neuritis (EAN), the current study investigated the antigen-presenting capacity of Schwann cells (SCs) in EAN induced by P0 protein peptide 106–125 in TNF-α recepter 1 deficient (TNFR1−/−) mice. The antigen-presenting capacity of SCs was assessed by the expression of MHC class II (MHCII), CD40, CD80 and CD86 molecules on activated SCs as well as by induction of T cell proliferation in co-cultures of P0 protein peptide 106–125 specific T cells with activated SCs. In addition, the expression of inducible nitric oxide synthase (iNOS) was measured in activated SCs by flow cytometry. TNFR1−/− EAN mice developed significantly delayed and reduced clinical signs of EAN compared to wild type EAN mice. In parallel, the expression of MHCII, CD80 and iNOS on SCs were decreased in TNFR1−/− mice compared to wild type mice. Likewise, proliferation of P0 protein peptide 106–125 specific T cells simulated by activated SCs of TNFR1−/− EAN mice was lower than that of wild type EAN mice. Our data suggest that TNF-α may exert pro-inflammatory effects in EAN via TNFR1 by up-regulating the antigen-presenting function and iNOS production of SCs. 相似文献