Living Bacterial Sacrificial Porogens to Engineer Decellularized Porous Scaffolds

Decellularization and cellularization of organs have emerged as disruptive methods in tissue engineering and regenerative medicine. Porous hydrogel scaffolds have widespread applications in tissue engineering, regenerative medicine and drug discovery as viable tissue mimics. However, the existing hydrogel fabrication techniques suffer from limited control over pore interconnectivity, density and size, which leads to inefficient nutrient and oxygen transport to cells embedded in the scaffolds. Here, we demonstrated an innovative approach to develop a new platform for tissue engineered constructs using live bacteria as sacrificial porogens. E.coli were patterned and cultured in an interconnected three-dimensional (3D) hydrogel network. The growing bacteria created interconnected micropores and microchannels. Then, the scafold was decellularized, and bacteria were eliminated from the scaffold through lysing and washing steps. This 3D porous network method combined with bioprinting has the potential to be broadly applicable and compatible with tissue specific applications allowing seeding of stem cells and other cell types

Fabry Disease Prevalence in Renal Replacement Therapy in Turkey

Background: Fabry disease (FD) is an X-linked lysosomal storage disorder resulting from lack of alpha-galactosidase A (AGALA) activity in lysosomes. Objective: In this multicenter study, we aimed to evaluate the prevalence of FD in renal transplant (Tx) recipients in Turkey. We also screened dialysis patients as a control group. Methods: All Tx and dialysis patients were screened regardless of the presence of a primary disease. We measured the AGALA activity in all male patients as initial analysis. Mutation analysis was performed in male patients with decreased AGALA activity and in female patients as the initial diagnostic assay. Results: We screened 5,657 patients. A total of 17 mutations were identified. No significant difference was observed between the groups regarding the prevalence of patients with mutation. We found FD even in patients with presumed primary kidney diseases. Seventy-one relatives were analyzed and mutation was detected in 43 of them. We detected a patient with a new, unknown mutation (p.Cys223) in the GLA gene. Conclusions: There are important implications of the screening. First, detection of the undiagnosed patients leads to starting appropriate therapies for these patients. Second, the transmission of the disease to future generations may be prevented by prenatal screening after appropriate genetic counseling. In conclusion, we suggest screening of kidney Tx candidates for FD, regardless of etiologies of chronic kidney disease. (C) 2019 S. Karger AG, BaselC1 [Yalin, Serkan Feyyaz; Senates, Banu Erkalma; Oruc, Meric; Altiparmak, Mehmet Riza; Seyahi, Nurhan] Istanbul Univ Cerrahpasa, Cerrahpasa Med Fac, Dept Nephrol, Istanbul, Turkey.[Eren, Necmi] Kocaeli Univ, Dept Nephrol, Med Fac, Kocaeli, Turkey.[Sinangil, Ayse; Ecder, Tevfik] Bilim Univ, Dept Nephrol, Med Fac Med, Istanbul, Turkey.[Yilmaz, Vural Taner; Kocak, Huseyin] Akdeniz Univ, Div Nephrol, Med Fac, Antalya, Turkey.[Tatar, Erhan; Uslu, Adam] Bozyaka Training & Res Hosp, Dept Nephrol, Izmir, Turkey.[Ucarf, Ali Riza; Demir, Erol; Caliskan, Yasar; Turkmen, Aydin] Istanbul Univ, Fac Med, Div Nephrol, Istanbul, Turkey.[Sevinc, Mustafa; Basturk, Taner] Sisli Hamidiye Etfal Training & Res Hosp, Dept Nephrol, Istanbul, Turkey.[Can, Ozgur; Ogutmen, Melike Betul] Haydarpasa Training & Res Hosp, Dept Nephrol, Istanbul, Turkey.[Gurkan, Alp; Kinalp, Can] Medicana, Dept Nephrol, Istanbul, Turkey.[Arik, Nurol] Ondokuz Mayis Univ, Dept Nephrol, Med Fac, Samsun, Turkey.[Ecder, Sabahat Alisir] Medeniyet Univ, Div Nephrol, Goztepe Training & Res Hosp, Istanbul, Turkey.[Uyar, Murathan] Gaziosmanpasa Hosp, Dept Nephrol, Istanbul, Turkey.[Yasar, Murat; Dursun, Belda] Pamukkale Univ, Dept Nephrol, Med Fac, Denizli, Turkey.[Gulcicek, Sibel] Istanbul Training & Res Hosp, Dept Nephrol, Istanbul, Turkey.[Mese, Meral; Bahcebasi, Zerrin Bicik] Dr Lufti Kirdar Kartal Training & Res Hosp, Dept Nephrol, Istanbul, Turkey.[Dheir, Hamad; Sipahi, Savas; Genc, Ahmed] Sakarya Univ, Dept Nephrol, Tip Med Fac, Sakarya, Turkey.[Cakir, Ulkem] Acibadem Univ, Dept Nephrol, Med Fac, Istanbul, Turkey.[Cevher, Simal Koksal; Dede, Fatih] Ankara Numune Training & Res Hosp, Dept Nephrol, Ankara, Turkey.[Turkmen, Kultigin] Necmettin Erbakan Univ, Div Nephrol, Meram Med Fac, Konya, Turkey.[Guven, Bahtisen] Bahcesehir Univ, Dept Nephrol, Med Fac, Istanbul, Turkey.[Taymez, Dilek Guven] Kocaeli State Hosp, Dept Nephrol, Kocaeli, Turkey.[Yelken, Berna] Mem Hosp, Dept Nephrol, Istanbul, Turkey

Exostoses of the Bony Pyramid of the Nose : A Review About an Adaptive Response to Mechanical Stimuli Exerted by In-Flight Oxygen Masks

This review addresses thickening of the bony pyramid of the nose, a condition that is caused by in-flight oxygen masks in otherwise healthy Royal Netherlands Air Force (RNLAF) F-16 pilots. The overlying skin may show temporary or permanent reddening, irritation, thickening and may become painful. Both in vitro and in vivo animal research has shown that mechanical stimuli are converted into a biochemical response through a process called mechanotransduction. Examination of the RNLAF F-16 pilots showed that the oxygen mask exerts pressure and friction on the nose. The biochemical response to chronic exposure to these stimuli results in the development of skin conditions and eventually exostoses of the bony pyramid of the nose. Painful skin conditions are most frequently observed, while the development of exostoses is rare. It lies at the extreme end of the spectrum of the pilots’ nasal conditions. The suboptimal fit of their work gear probably contributes to the pilots’ soft and bony tissue nasal conditions. Explaining the pathogenesis of the development of exostoses may aid in the development of preventive measures. Also, the obtained knowledge may be of use in similar occupational health issues that involve mechanical loading. Our conclusions are that areas containing osteocyte precursors and covered by a relatively thin cushioning layer are prone to develop a soft tissue and bony tissue response when they are chronically exposed to intermittently exerted, mechanical stimuli of sufficiently high magnitude. Modification of the suboptimally fitting oxygen mask–helmet assembly is needed to prevent symptoms associated with its use