murine-distal-colostomy-novel-model-diversion-colitis-c57bl6

Murine Distal Colostomy, A Novel Model of Diversion Colitis in C57BL/6 Mice

Diversion colitis (DC) is a frequent clinical condition occurring in patients with bowel segments excluded from the fecal stream as a result of a ...

Universitätsmedizin Greifswald

In Germany, over half a million operations are done in dermatologic surgery in a hospital setting every year, as well as a less well quantified number of procedures in private offices. In spite of this large number, specific guidelines concerning the use of perioperative antibiotics in dermatologic surgery are sparse. In contrast to procedures in general, visceral or gynecological surgery, general guidelines on perioperative antibiotics issued by the Paul-Ehrlich Institutes and the AWMF do not specifically consider dermatologic operations. Several surveys indicate that familiarity with current recommendations on perioperative antibiotics is suboptimal and resulted in a considerable overuse of perioperative antibiotics in dermatologic surgery. Given the increasing antimicrobial resistance among important pathogens and the inherent risks of antibiotic administration, the decision for the use of prophylactic antibiotics should be based on the individual risk profile of the patient and of the surgical procedure. In the following, we will critically discuss the evidence for perioperative antibiotics in dermatologic surgery. 

[Antibiotic prophylaxis in dermatologic and soft tissue surgery].

Although the mortality associated with major hepatopancreaticobiliary surgery has continuously decreased during the last decades, the morbidity of these procedures remains high. Functional disturbances of normal gastrointestinal motility as well as inflammation and infections of surgically treated organs are frequent complications resulting in considerably prolonged lengths of stay in hospital and increased healthcare costs. This review article highlights the therapeutic approaches and recent developments in the treatment of delayed gastric emptying, prolonged postoperative ileus, postoperative cholangitis and pancreatitis after hepatopancreaticobiliary surgery. Current practice is discussed on the basis of recent results in basic and clinical research, review articles, meta-analyses and guidelines.

[Treatment of postoperative impairment of gastrointestinal motility, cholangitis and pancreatitis].

FTY720 is an immunosuppressive molecule licensed for the treatment of chronic relapsing multiple sclerosis (MS). It attenuates the adaptive immune response by sequestering T cells within secondary lymphoid organs via its action as functional antagonist of sphingosine-1-phasphate. To date, it is unknown whether FTY-induced lymphopenia puts MS patients at increased risk for severe forms of postoperative infectious complications such as abdominal sepsis.

FTY720-Induced Lymphopenia Does Not Aggravate Mortality in a Murine Model of Polymicrobial Abdominal Sepsis.

. Macrophages are key players in complex biological processes. In response to environmental signals, macrophages undergo polarization towards a proinflammatory (M1) or anti-inflammatory (M2) phenotype. Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid that acts via 5 G-protein coupled receptors (S1P) in order to influence a broad spectrum of biological processes. This study assesses S1P receptor expression on macrophages before and after M1 and M2 polarization and performs a comparative analysis of S1P signalling in the two activational states of macrophages. . Bone marrow derived macrophages (BMDM) from C57 BL/6 mice were cultured under either M1- or M2-polarizing conditions. S1P-receptor expression was determined by quantitative RT-PCR. Influence of S1P on macrophage activation, migration, phagocytosis, and cytokine secretion was assessed in vitro. . All 5 S1P receptor subclasses were expressed in macrophages. Culture under both M1- and M2-polarizing conditions led to significant downregulation of S1P. In contrast, M1-polarized macrophages significantly downregulated S1P. The expression of the remaining three S1P receptors did not change. S1P increased expression of iNOS under M2-polarizing conditions. Furthermore, S1P induced chemotaxis in M1 macrophages and changed cytokine production in M2 macrophages. Phagocytosis was not affected by S1P-signalling. . The expression of different specific S1P receptor profiles may provide a possibility to selectively influence M1- or M2-polarized macrophages.

Differential S1P Receptor Profiles on M1- and M2-Polarized Macrophages Affect Macrophage Cytokine Production and Migration.

Diversion colitis is a significant health problem due to its high incidence in patients with diverting enterostomy. This mucosal inflammation presents characteristic histopathological features allowing for the differentiation of this entity from other inflammatory bowel diseases. The pathophysiology of this disease remains ill-defined, in part due to the lack of appropriate animal models. The present study was performed in order to develop and characterize a murine model of diversion colitis.

Deviation of the Fecal Stream in Colonic Bowel Segments Results in Increased Numbers of Isolated Lymphoid Follicles in the Submucosal Compartment in a Novel Murine Model of Diversion Colitis.

 Sphingosine-1-phosphate (S1P) regulates the migration of follicular B cells (B2 cells) and directs the positioning of Marginal zone B cells (MZ B cells) within the spleen. The function of S1P signalling in the third B cell lineage, B1 B cells, mainly present in the pleural and peritoneal cavity, has not yet been determined.  S1P receptor expression was analysed in peritoneal B cells by real-time polymerase chain reaction (qPCR). The chemotactic response to S1P was studied in vitro. The role of S1P signalling was further explored in a s1p₄ mouse strain.  Peritoneal B cells expressed considerable amounts of the S1P receptors 1 and 4 (S1P₁ and S1P₄, respectively). S1P₁ showed differential expression between the distinct peritoneal B cell lineages. While B2 cells showed no chemotactic response to S1P, B1 B cells showed a migration response to S1P. s1p₄ mice displayed significant alterations in the composition of peritoneal B cell populations, as well as a significant reduction of mucosal immunoglobulin A (IgA) in the gut.  S1P signalling influences peritoneal B1 B cell migration. S1P₄ deficiency alters the composition of peritoneal B cell populations and reduces secretory IgA levels. These findings suggest that S1P signalling may be a target to modulate B cell function in inflammatory intestinal pathologies.

Article	Year
[Antibiotic prophylaxis in dermatologic and soft tissue surgery]. Der Hautarzt; Zeitschrift fur Dermatologie, Venerologie, und verwandte Gebiete\| PubMed ID: 24337238	2014
[Treatment of postoperative impairment of gastrointestinal motility, cholangitis and pancreatitis]. Der Chirurg; Zeitschrift fur alle Gebiete der operativen Medizen\| PubMed ID: 25986675	2015
FTY720-Induced Lymphopenia Does Not Aggravate Mortality in a Murine Model of Polymicrobial Abdominal Sepsis. Shock (Augusta, Ga.)\| PubMed ID: 27559700	2017
Differential S1P Receptor Profiles on M1- and M2-Polarized Macrophages Affect Macrophage Cytokine Production and Migration. BioMed research international\| PubMed ID: 28367448	2017
Deviation of the Fecal Stream in Colonic Bowel Segments Results in Increased Numbers of Isolated Lymphoid Follicles in the Submucosal Compartment in a Novel Murine Model of Diversion Colitis... BioMed research international\| PubMed ID: 28884123	2017
S1P Signalling Differentially Affects Migration of Peritoneal B Cell Populations In Vitro and Influences the Production of Intestinal IgA In Vivo. International journal of molecular sciences\| PubMed ID: 29382132	2018

Tobias Schulze

Biography

JoVE Journal Publications

Other Publications