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Aldosterone exerts an enormous function on proximal tubular cells (PTC) senescence, which is a common pathomechanism contributing to renal dysfunction. Numerous studies have shown that oxidative stress is deeply involved in the pathophysiologic processes of chronic kidney diseases. The study aims to investigate whether autophagy could regulate the process of senescence through oxidative stress in PTC both in vivo and ex vivo. Our results suggested that aldosterone treatment increased the senescence and oxidative stress as evidenced by increased percent of SA-β-Gal positive cells, reactive oxygen species level, expression of NADPH oxidase 4 (NOX4) rather than NOX2, and the up-regulation of p21 in cultured PTC. Furthermore, the alternation of the expression of p62 and LC3-II/LC3-I demonstrated that aldosterone treatment remarkably influenced autophagic flux. NOX4 siRNA treatment or autophagy induction with rapamycin reduced the oxidative stress and senescence in aldosterone-induced PTC. On the contrary, inhibition of autophagy with chloroquine worsened these changes. Similar results were further confirmed in vivo. Our results suggested that autophagy may become a realistic therapeutic strategy against aldosterone-induced PTC injury via improving oxidative stress.

Soft tissue engineering requires antifouling materials that are biocompatible and mechanically flexible. Conventional hydrogels containing more than 70 wt% water are thus promising antifouling material candidates. However, some hydrogels are difficult to apply in internal body organs because of undesirable protein absorption on their surfaces. Due to the lack of an effective method for observing the true charge densities of hydrogels, the reason why electrostatic interactions dominate protein absorption behavior remains unclear. In this work, we adopt the microelectrode technique (MET) to study the electrical potentials of hydrogels with negative, positive, and neutral potentials and demonstrate the protein absorption behaviors on those hydrogels. The results show that MET is an effective method to obtain the surface charge densities of various hydrogels. Furthermore, the amounts of absorbed proteins on the gels were quantified with respect to the charge densities of the hydrogels. The results indicate that electrostatic absorption is quantitatively dominated by a combination of hydrogel charge density and overall protein charge. Based on the knowledge obtained in this work, the effects of hydrogel surface charges on protein absorption can be better understood. Thus, the results are expected to promote the application of hydrogels in tissue engineering.

Foot process effacement is an important feature of early diabetic nephropathy (DN) which is closely related to the development of albuminuria. Under certain nephrotic conditions, the integrity and function of the glomerular slit diaphragm (SD) structure were impaired and replaced by the tight junction (TJ) structure, resulting in so-called SD-TJ transition, which could partially explain the effacement of foot processes at the molecular level. However, the mechanism underlying the SD-TJ transition has not been described in DN. Here, we demonstrated that impaired autophagic flux blocked p62 mediated degradation of ZO-1 (TJ protein) and promoted podocytes injury via activation of caspase 3 and caspase 8. Interestingly, the expression of VDR in podocytes was decreased under diabetic condition which impaired autophagic flux through down-regulating Atg3. Of note, we also found that VDR abundance was negatively associated with impaired autophagic flux and SD-TJ transition in the glomeruli from human renal biopsy samples with DN. Furthermore, VDR activation improved autophagic flux and attenuated SD-TJ transition in the glomeruli of diabetic animal models. In conclusion, our data provided the novel insight that VDR/Atg3 axis deficiency resulted in SD-TJ transition and foot processes effacement via blocking p62-mediated autophagy pathway in DN.

Bimodal classification of idiopathic chronic pancreatitis (ICP) into early-onset (35 years) ICP was proposed in 1994 based on a study of 66 patients. However, bimodal distribution wasn’t sufficiently demonstrated. Our objective was to examine the validity and relevance of the age-based bimodal classification of ICP. We analyzed the distribution of age at onset of ICP in our cohort of 1633 patients admitted to our center from January 2000 to December 2013. Classify ICP patients into early-onset ICP(a) and late-onset ICP(a) according to different cut-off values (cut-off value, a = 15, 25, 35, 45, 55, 65 years old) for age at onset. Compare clinical characteristics of early-onset ICP(a) and late-onset ICP(a). We found slightly right skewed distribution of age at onset for ICP in our cohort. There were differences between early-onset and late-onset ICP with respect to basic clinical characteristics and development of key clinical events regardless of the cut off age at onset i.e. 15, 25, 35, 45 or even higher. The validity of the bimodal classification of early-onset and late-onset ICP could not be established in our large patient cohort and therefore such a classification needs to be reconsidered.

The extreme mechanical strength of fibrous connective tissues in the human body, such as ligaments and tendons, has always been challenging for hydrogel scientists. Here, we created extremely strong, purely cellulose-based hydrogels (DCC-E gels). The fracture stress and Young’s modulus of the gels were improved to the level of an Achilles tendon even at their equilibrium swollen state. To make DCC-E gels, regenerated cellulose gels were first prepared with ethanol as the anti-solvent. DCC-E gels were then prepared by applying Drying in Confined Condition method, where regenerated cellulose gels were prestretched and dried while their length was fixed. Although strength improvement of materials is typically only achieved at the expense of toughness, a significant increase in strength was achieved while maintaining high levels of toughness. The high strength and toughness of the DCC-E gels were realized by optimizing the cellulose fibril arrangement from nanoscale to macroscale, which was done by selection of an appropriate solvent used for cellulose regeneration. Parallel aggregated fibrous structures observed in the DCC-E gels are thought to play a central role in the enhancement of both toughness and strength. This study can assist in expanding the application of biopolymer-based hydrogels in tissue engineering and soft electronics.

Pediatric patients suffer from chronic pancreatitis (CP), especially those with diabetes mellitus (DM). This study aimed to identify the incidence of and risk factors for DM in pediatric CP. CP patients admitted to our center from January 2000 to December 2013 were assigned to the pediatric (

BackgroundChronic pancreatitis (CP) is a chronic inflammatory disease of the pancreas. This study aimed to compare the natural course of alcoholic chronic pancreatitis (ACP) and idiopathic chronic pancreatitis (ICP).MethodsCP patients admitted to our center from January 2000 to December 2013 were enrolled. Characteristics were compared between ACP and ICP patients. Cumulative rates of diabetes mellitus (DM), steatorrhea, pancreatic stone, pancreatic pseudocyst, biliary stricture, and pancreatic cancer after the onset and the diagnosis of CP were calculated, respectively. The cumulative rates of DM and steatorrhea after diagnosis of pancreatic stone were also calculated.ResultsA total of 2,037 patients were enrolled. Among them, 19.8% (404/2,037) were ACP and 80.2% (1,633/2,037) were ICP patients. ACP and ICP differs in many aspects, especially in gender, age, smoking, complications, morphology of pancreatic duct, and type of pain. The development of DM, steatorrhea, PPC, pancreatic stone, and biliary stricture were significantly earlier and more common in ACP patients. No significant difference was observed for pancreatic cancer development. There was a rather close correlation between exocrine/endocrine insufficiency and pancreatic stone in ACP patients, which was much less correlated in ICP patients.ConclusionThe long-term profile of ACP and ICP differs in some important aspects. ACP patients usually have a more severe course of CP. These differences should be recognized in the diagnosis and treatment of CP.