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The physiology and pathophysiology of the exocrine pancreas are in close connection to changes in intra-cellular Ca2+ concentration. Most of our knowledge is based on in vitro experiments on acinar cells or acini enzymatically isolated from their surroundings, which can alter their structure, physiology, and limit our understanding. Due to these limitations, the acute pancreas tissue slice technique was introduced almost two decades ago as a complementary approach to assess the morphology and physiology of both the endocrine and exocrine pancreas in a more conserved in situ setting. In this study, we extend previous work to functional multicellular calcium imaging on acinar cells in tissue slices. The viability and morphological characteristics of acinar cells within the tissue slice were assessed using the LIVE/DEAD assay, transmission electron microscopy, and immunofluorescence imaging. The main aim of our study was to characterize the responses of acinar cells to stimulation with acetylcholine and compare them with responses to cerulein in pancreatic tissue slices, with special emphasis on inter-cellular and inter-acinar heterogeneity and coupling. To this end, calcium imaging was performed employing confocal microscopy during stimulation with a wide range of acetylcholine concentrations and selected concentrations of cerulein. We show that various calcium oscillation parameters depend monotonically on the stimulus concentration and that the activity is rather well synchronized within acini, but not between acini. The acute pancreas tissue slice represents a viable and reliable experimental approach for the evaluation of both intra- and inter-cellular signaling characteristics of acinar cell calcium dynamics. It can be utilized to assess many cells simultaneously with a high spatiotemporal resolution, thus providing an efficient and high-yield platform for future studies of normal acinar cell biology, pathophysiology, and screening pharmacological substances.

Secondary aortoenteric fistulas (SAEF ) are a relatively rare but dangerous complication of aortal reconstructive surgery. We present a patient that underwent aortobifemoral bypass three years before developing the signs of aortoenteric fistula, and we reviewed the literature on the topic. Since the clinical signs are nonspecific, physicians should have a high index of suspicion for SAEF in patients who underwent aortal reconstructive surgery. The most useful diagnostic tools for stable patients are upper gastrointestinal endoscopy and computed tomography scan with contrast that can, in combination with history and clinical signs, enable accurate diagnosis in more than 90% of patients. Unstable patients with suspected aortoenteric fistula should undergo exploratory laparotomy. The treatment of choice is open surgery with graft excision, wide debridement of infected tissue, bowel repair or resection followed by an extra-anatomic bypass or in situ placement of a new graft. Early postoperative mortality remains high, around 30% in most analyses. Currently there are no guidelines for the diagnosis and management of SAEF , so individualized approach is necessary for each patient., Sekundarne aorto-enteralne fistule su rijetka ali opasna komplikacija aortne rekonstruktivne kirurgije. Prikazuje se bolesnik kod kojega su se razvili simptomi aorto-enteralne fistule tri godine nakon ugradnje aorto-bifemoralne premosnice, uz pregled literature. S obzirom na to da su klinički znaci vrlo nespecifični kod ovih bolesnika, važno je rano posumnjati na moguć razvoj sekundarne aorto-enteralne fistule kod bolesnika koji su bili podvrgnuti aortnoj rekonstruktivnoj kirurgiji. Od dijagnostičkih metoda najkorisnije su ezofagogastroduodenoskopija i kompjutorizirana tomografija s kontrastom koji, u kombinaciji s anamnezom i kliničkim znacima, omogućavaju postavljanje dijagnoze u preko 90% bolesnika. U nestabilnih bolesnika kod kojih postoji sumnja na razvoj ovoga stanja indicirana je eksplorativna laparotomija. U liječenju metoda izbora je laparotomija, ekscizija proteze, debrideman upaljenog tkiva, popravak defekta na crijevu ili resekcija zahvaćenog segmenta, te ekstraanatomska premosnica ili postavljanje nove proteze. Poslijeoperacijska smrtnost je oko 30%. Kako zasad nema smjernica za dijagnostiku i liječenje bolesnika sa sekundarnim aorto-enteralnim fistulama nužan je visoko individualizirani pristup za svakog bolesnika.