Chiral Nanoclusters as Alternative Therapeutic Strategies to Confront the Health Threat from Antibiotic-Resistant Pathogens.

Pseudomonas aeruginosa (P. aeruginosa), a drug-resistant Gram-negative pathogen, is listed among the "critical" group of pathogens by the World Health Organization urgently needing efficacious antibiotics in the clinics. Nanomaterials especially silver nanoparticles (AgNPs) due to the broad-spectrum antimicrobial activity are tested in antimicrobial therapeutic applications. Pathogens rapidly develop resistance to AgNPs; however, the health threat from antibiotic-resistant pathogens remains challenging. Here we present a strategy to prevent bacterial resistance to silver nanomaterials through imparting chirality to silver nanoclusters (AgNCs). Nonchiral AgNCs with high efficacy against P. aeruginosa causes heritable resistance, as indicated by a 5.4-fold increase in the minimum inhibitory concentration (MIC) after 9 repeated passages. Whole-genome sequencing identifies a Rhs mutation related to the wall of Gram-negative bacteria that possibly causes morphology changes in resistance compared to susceptible P. aeruginosa. Nevertheless, AgNCs with laevorotary chirality (l-AgNCs) induce negligible resistance even after 40 repeated passages and maintain a superior antibacterial efficiency at the MIC. l-AgNCs also show high cytocompatibility; negligible cytotoxicity to mammalian cells including JB6, H460, HEK293, and RAW264.7 is observed even at 30-fold MIC. l-AgNCs thus are examined as an alternative to levofloxacin in vivo, healing wound infections of P. aeruginosa efficaciously. This work provides a potential opportunity to confront the rising threat of antimicrobial resistance by developing chiral nanoclusters.

Integrated omic profiling of the medicinal mushroom Inonotus obliquus under submerged conditions.

BACKGROUND: The Inonotus obliquus mushroom, a wondrous fungus boasting edible and medicinal qualities, has been widely used as a folk medicine and shown to have many potential pharmacological secondary metabolites. The purpose of this study was to supply a global landscape of genome-based integrated omic analysis of the fungus under lab-growth conditions. RESULTS: This study presented a genome with high accuracy and completeness using the Pacbio Sequel II third-generation sequencing method. The de novo assembled fungal genome was 36.13 Mb, and contained 8352 predicted protein-coding genes, of which 365 carbohydrate-active enzyme (CAZyme)-coding genes and 19 biosynthetic gene clusters (BCGs) for secondary metabolites were identified. Comparative transcriptomic and proteomic analysis revealed a global view of differential metabolic change between seed and fermentation culture, and demonstrated positive correlations between transcription and expression levels of 157 differentially expressed genes involved in the metabolism of amino acids, fatty acids, secondary metabolites, antioxidant and immune responses. Facilitated by the widely targeted metabolomic approach, a total of 307 secondary substances were identified and quantified, with a significant increase in the production of antioxidant polyphenols. CONCLUSION: This study provided the comprehensive analysis of the fungus Inonotus obliquus, and supplied fundamental information for further screening of promising target metabolites and exploring the link between the genome and metabolites.

Intramolecular Folding of PolyT Oligonucleotides Induced by Cooperative Binding of Silver(I) Ions.

Ag+-bridged T-Ag+-T was recently discovered in a Ag+-DNA nanowire crystal, but it was reported that Ag+ had little to no affinity to T nucleobases and T-rich oligonucleotides in solution. Therefore, the binding mode for the formation of this type of novel metallo base pair in solution is elusive. Herein, we demonstrate that Ag+ can interact with polyT oligonucleotides once the concentration of Ag+ in solution exceeds a threshold value. The threshold value is independent of the concentration of the polyT oligonucleotide but is inversely proportional to the length of the polyT oligonucleotide. The polyT oligonucleotides are intramolecularly folded due to their positively cooperative formation and the stack of T-Ag+-T base pairs, resulting in the 5'- and 3'-ends being in close proximity to each other. The intramolecular Ag+-folded polyT oligonucleotide has a higher thermal stability than the duplex and can be reversibly modulated by cysteine.

Controlled release of iodine from cross-linked cyclodextrin metal-organic frameworks for prolonged periodontal pocket therapy.

Effective therapeutic system to periodontitis was designed using cross-linked cyclodextrin metal-organic framework (COF) as carrier for iodine and further suspended in hydroxyethyl cellulose gel as I2@COF-HEC hydrogel. Inclusion of iodine within the COF was demonstrated by SR-FTIR spectral and characteristic DSC and TGA changes. Molecular modelling identified the interaction of iodine with both COF central cavity and individual cyclodextrin moieties of COF. In vitro results of study demonstrated that iodine release in artificial saliva from I2@COF-HEC hydrogel could be extended up to 5 days, which was slower than I2@COF particles. Using an in vivo rat model of periodontitis, micro-computed tomography of alveolar bone morphology demonstrated that I2@COF-HEC hydrogel showed similar effects in decreasing periodontal pocket depth and alveolar bone resorption to minocycline ointment, a periodontitis antibiotic. The I2@COF-HEC hydrogel is a novel local delivery device of iodine as a broad spectrum antimicrobial use for treatment of periodontitis.

Nrf2-induced miR-23a-27a-24-2 cluster modulates damage repair of intestinal mucosa by targeting the Bach1/HO-1 axis in inflammatory bowel diseases.

IBD is an idiopathic, chronic autoimmune disease associated with intense oxidative stress. As a master modulator of oxidative stress, Nrf2 has an important anti-inflammatory role in colitis by activating HO-1 transcription. Meanwhile, HO-1 expression is transcriptionally suppressed by Bach1. The Nrf2-activated HO-1 transcription depends on the inactivation of Bach1. However, how Bach1 is inactivated and how Nrf2, Bach1 and HO-1 participate in IBD remains elusive. We found that in response to inflammatory stimuli, Nrf2-induced transcription of miR-23a-27a-24-2 cluster directly inhibits Bach1 expression by binding to the 3'UTR and thereby relieved the Bach1-mediated suppression of HO-1. Besides, elevated miR-23a, miR-27a and miR-24-2 promotes the proliferation and wound healing through regulating Bach1/HO-1 expression in SW480 cell. Additionally, miR-23a, miR-27a and miR-24-2 exert a protective effect on the intestinal mucosa in DSS-induced colitis mouse model. In conclusion, our study revealed that the Nrf2/miR-23a-27a-24-2/Bach1/HO-1 regulatory axis promotes the damage repair of intestinal mucosa during the development of inflammatory bowel diseases.

Nasal mucosa pyoderma vegetans associated with ulcerative colitis: A case report.

BACKGROUND: Pyoderma vegetans (PV) is not a common extra-intestinal manifestation of ulcerative colitis (UC), while nasal mucosa PV associated with UC is particularly rare. CASE SUMMARY: We report a 28-year-old female with a history of UC and pyoderma gangrenosum who presented with nasal pain. A nasal lesion could be observed in her nose, and histopathological examination was indicative of PV. The patient was treated with oral prednisone (40 mg per day) with good response and became symptomatically free. There was no recurrent attack after 1 year of follow-up. CONCLUSION: Inflammatory bowel disease patients presenting with nasal pain should be further investigated to rule out the coexistence of nasal mucosa PV.

Correlation of Hypoxia-inducible facto-1α and C-reactive protein with disease evaluation in patients with ulcerative colitis.

OBJECTIVE: To investigate the expression levels of hypoxia-inducible factor-1α (HIF-1α) and C-reactive protein (CRP) in patients with ulcerative colitis and correlations of HIF-1α and CRP levels with disease severity. METHODS: A total of 82 patients with confirmed ulcerative colitis were enrolled in this study and according to the disease severity grading, these patients were assigned into three groups: mild group (n=25), moderate group (n=31) and severe group (n=26). And other 30 patients without ulcerative colitis as demonstrated by colonoscopy examination were enrolled in control group in the same period. HIF-1α and CRP levels were detected by ELISA and Real-time PCR and compared among different groups. Pearson's correlation analysis was performed to evaluate the correlations of HIF-1α and CRP levels with disease severity. Logistic regression analysis was used to explore risk factors of disease severity in patients with ulcerative colitis. RESULTS: The expression levels of HIF-1α and CRP in ulcerative colitis group were significantly higher than those in control group (all P<0.001). The levels of HIF-1α and CRP in patients with ulcerative colitis increased remarkably with the increase of disease severity. Patients in mild group had the lowest levels of HIF-1α and CRP, while patients in severe group had the highest levels of HIF-1α and CRP. Logistic regression analysis showed that the expression of HIF-1α and CRP were the risk factors for disease severity of ulcerative colitis (all P<0.001). And Pearson correlation analysis showed that HIF-1α and CRP levels were significantly associated with Rachmilewitz score and disease activity index (DAI), respectively (all P<0.001). CONCLUSION: The levels of HIF-1α and CRP were up-regulated in patients with ulcerative colitis and positively correlated with the progression of ulcerative colitis, indicating that the detection of HIF-1α and CRP expression could be used for predicting the disease severity.

Comparison of different endoscopic resection techniques for submucosal tumors originating from muscularis propria at the esophagogastric junction.

BACKGROUND: To compare the outcomes of submucosal tunneling endoscopic resection (STER) and submucosal excavation (ESE) for the treatment of submucosal tumors (SMTs) arising from the muscularis propria (MP) at the esophagogastric junction (EGJ). METHODS: A retrospective analysis of patients with SMTs at EGJ who underwent STER and ESE from October 2011 to October 2017 was performed. The outcomes evaluated were operation time, complete resection rate, adverse events, and tumor recurrence. RESULTS: Ninety patients were included in this study. Complete resection rates in the STER group were higher than those of the ESE group (100 vs. 92%, p < 0.05). For tumors ≤15 mm, both techniques achieved 100% complete resection rate; but for tumors > 15 mm, complete resection rate was higher in the STER group than the ESE group (100% vs. 77.8%, p < 0.05). Subgroup analyses revealed that the operation time of STER for in cardiac-gastric group was longer than that for ESE (145.14 ± 42.43 min vs. 70.32 ± 39.84 min, p <  0.05). The air leakage symptoms were more frequent in STER group (90.9% vs. 50.0%, p < 0.05). No tumor recurrence occurred in both the STER and ESE groups. CONCLUSIONS: For SMTs ≤15 mm, both STER and ESE have similar satisfactory therapeutic outcomes. However, in the cardiac-gastric subgroup, STER had a longer operative time compared to the ESE procedure. For SMTs > 15 mm, STER is the preferred choice due to its higher complete resection rate.

The effect of solid pancreatic mass lesions on pancreatic duct diameter at endoscopic ultrasound.

OBJECTIVES: To evaluate the effect of solid pancreatic masses on the pancreatic duct (PD) at the endoscopic ultrasound (EUS) and the relationship of the location/size of a mass and PD dilation. MATERIALS AND METHODS: Patients who underwent EUS for pancreatic indications from 2011 to 2013 at a single center were retrospectively identified. Those with biopsies that revealed adenocarcinoma or neuroendocrine tumors in the pancreas were identified and PD size was ascertained from EUS, computed tomography, or magnetic resonance imaging. RESULTS: Of the 475 patients who had a pancreatic EUS, 239 had a dilated PD and 236 had a normal PD. Patients with a dilated PD had a significantly higher incidence of pancreatic malignancy than those with a normal PD diameter (106/239, 44.4% vs. 32/236, 13.6%, P< 0.001). Of the 138 patients with a pancreatic malignancy, 106 (76.8%) had a dilated PD at some location in the pancreas. Over 80% of patients with a mass within the head, neck, or body had a dilated PD. For a mass located at the uncinate process or the tail, PD dilation was 65% and 23%, respectively. Fifty-six (80.0%) of the masses in the head, 11 (78.6%) masses in the neck, and 16 (76.2%) masses in the body had a dilated PD upstream of the mass. In addition, a step-wise increase in the incidence of PD dilation was correlated with an increase in mass size. About 67.6% of patients with masses measuring in the 1st quartile had dilated a PD, while 77.8%, 91.0%, and 71.4% of those with masses measuring in the 2nd, 3rd, and 4th quartiles, respectively, had a dilated PD. CONCLUSION: PD dilation is a warning sign for pancreatic malignancies, however, small masses or masses at the uncinate process or the tail of the pancreas may not affect the size of the PD.

A Prospective Study of Endoscopic Injection Sclerotherapy and Endoscopic Variceal Ligation in the Treatment of Esophageal Varices.

INTRODUCTION: The aim of this study was to compare the effectiveness and safety of endoscopic injection sclerotherapy (EIS) with endoscopic variceal ligation (EVL) in the management of esophageal variceal bleeding (EVB). PATIENTS AND METHODS: In this prospective study, we compared the EIS and EVL in 124 patients who had endoscopically proved bleeding from esophageal varices. According to different treatment methods, they were randomly divided into the EIS and the EVL groups. Sixty-four patients were treated with sclerotherapy and 60 with ligation. The patients were followed for a mean of 2 years, during which we determined the incidence of complications and recurrences of bleeding and the number of treatment sessions needed to eradicate varices, mortality, and survival. RESULTS: Active bleeding at the first treatment was controlled by EIS in 19 of 19 patients and by EVL in 16 of 16 patients. The likelihood of early rebleeding was slightly smaller in the patients treated with EIS (7.8% versus 11.7%, P = .47). However, late rebleeding rate was slightly more in EIS patients (28.1% versus 23.3%, P = .54) without statistical significance. The rate of eradication of varices in the EIS group was slightly lower than in the EVL group (79.7% versus 86.7%, P = .30). There were also no statistically significant differences in mortality (1.6% versus 3.3%, P = .61) or survival rate (71.9% versus 78.3%, P = .41) (all P > .05) after EIS and EVL. However, fever in the EIS group was significantly higher compared to that of in the EVL group (n = 17, 26.6% versus n = 6, 10.0%, P = .02). CONCLUSIONS: Both EIS and EVL produce excellent results, are safe, effective, feasible, and acceptable for EVB with minimum complications and obviate need for subsequent procedures in the short term. To make better choice, we should consider the hospital conditions, operator experience, and the characteristics of esophageal varices.

Submucosal tunneling endoscopic resection for tumors of the esophagogastric junction.

BACKGROUND: For submucosal tumors (SMTs) originating from the muscularis propria (MP) layer of the esophagogastric junction (EGJ), submucosal tunneling endoscopic resection (STER) is now widely used, and it shows promise in overcoming the limitations of endoscopic submucosal dissection. AIMS: This study aimed to evaluate the efficacy and safety of the STER technique for treating SMTs of the EGJ originating from the MP layer. MATERIAL AND METHODS: From October 2011 to February 2014, 20 patients were enrolled for STER surgery. RESULTS: The patients were categorized into three groups according to the tumor location. The esophagocardiac group had a lower complication rate (0/7) compared with the cardiac group (3/6) and the gastrocardiac group (3/7). The mean operation time in the esophagocardiac (83 ± 24 min) and cardiac (83 ± 55 min) groups was significantly shorter than that of the gastrocardiac group (145 ± 44 min) (P < 0.05). The en bloc resection rate was 100%, with no severe complications and no recurrence during the follow-up period. CONCLUSIONS: The STER technique appears to be a feasible and safe minimally invasive approach for SMTs originating from the MP layer of the EGJ, with satisfying en bloc resection, a short operation time, and low rates of severe complications.

Splenosis in gastric fundus mimicking gastrointestinal stromal tumor: a report of two cases and review of the literature.

Splenosis refers to heterotopic autotransplantation and implantation of splenic tissue following splenic trauma or surgery. Splenosis in gastric fundus is rare and difficult to diagnose, since splenosis has similar manifestation with gastrointestinal stromal tumor (GIST) under routine endoscopy examination. In this report, we present two quite rare case of splenosis. Both of their pre-operative diagnose under endoscopic ultrasonography was considered as GIST. Finally, one in the abdominal cavity, adhering closely to the gastric fundus, measuring 20 mm × 15 mm, was resected by surgical operation, and one in the gastric fundus, measuring 20 mm × 20 mm, was resected by endoscopic surgery. The precise diagnosis of splenosis was distinct by post-operative histopathologic examination. In addition, we also made a mini review of previously published articles, in order to provide indication to solve future doubts in diagnosing and treating splenosis.

Chondrogenesis of synovium-derived mesenchymal stem cells in gene-transferred co-culture system.

A co-culture strategy has been developed in this study wherein rabbit synovial mesenchymal stem cells (SMSCs) are co-cultured with growth factor (GF) transfected articular chondrocytes. Toward this end, both SMSCs and early passage rabbit articular chondrocytes that had been adenovirally transduced with transforming growth factor-beta 3 (TGF-beta3) gene were separately encapsulated in alginate beads and co-cultured in the same pool of chondrogenic medium. The chondrocytes act as transfected companion cells (TCCs) providing GF supply to induce chondrogenic differentiation of SMSCs that play the role of therapeutic progenitor cells (TPCs). Against the same TCC based TGF-beta3 release profile, the co-culture was started at different time points (Day 0, Day 10 and Day 20) but made to last for identical periods of exposure (30 days) so that the exposure conditions could be optimized in terms of initiation and duration. Transfection of TCCs prevents the stem cell based TPCs from undergoing the invasive procedure. It also prevents unpredictable complications in the TPCs caused by long-term constitutive over-expression of a GF. The adenovirally transfected TCCs exhibit a transient GF expression which results in a timely termination of GF supply to the TPCs. The TCC-sourced transgenic TGF-beta3 successfully induced chondrogenesis in the TPCs. Real-time PCR results show enhanced expression of cartilage markers and immuno/histochemical staining for Glycosaminoglycans (GAG) and Collagen II also shows abundant extracellular matrix (ECM) production and chondrogenic morphogenesis in the co-cultured TPCs. These results confirm the efficacy of directing stem cell differentiation towards chondrogenesis and cartilage tissue formation by co-culturing them with GF transfected chondrocytes.

A dual-functioning adenoviral vector encoding both transforming growth factor-beta3 and shRNA silencing type I collagen: construction and controlled release for chondrogenesis.

Hyaline articular cartilage degeneration is a common clinical syndrome globally, whereas cell-based therapy has proved to be a good solution to such problems. Given that transforming growth factor (TGF-beta3) is helpful in maintaining chondrocytic phenotype or stimulating chondrogenic differentiation of stem cells, vectors containing TGF-beta3 expression cassette can be delivered to therapeutic cells. One problem involved in the application of therapeutic cells in chondrogenesis is the undesirable production of type I collagen in such cells as chondrocytes and synovial mesenchymal stem cells during ex vivo culture, which undermines the mechanical strength of engineered cartilage. RNA interference (RNAi) strategy can be used to knock down its expression to allow better biological and mechanical functions in artificial tissues. In this study, for the first time we report the construction of an adenoviral vector that can express both TGF-beta3 to promote chondrogenesis and short hairpin RNA (shRNA) targeting type I collagen to block its production. This dual-functioning vector (Ad-dual) was found to function well in three model cell types: human fibroblast, osteoblast and porcine chondrocyte in terms of the release of TGF-beta3 protein and down-regulation of type I collagen production. Besides, we also tested its efficacy in porcine synovial mesenchymal stem cells, highlighting its potential applications in cell-based therapy for the treatment of articular cartilage degeneration.

Engineering osteogenesis and chondrogenesis with gene-enhanced therapeutic cells.

For bone and cartilage regeneration, a direct dose of growth factors or the viral or non-viral vector-mediated delivery of growth factor genes to the site of osteal or chondral wounds has disadvantages. These limitations include the short half-life and instability of the proteins, resulting in low efficacy with the repeated administration of the therapy, and the nonspecific targeting of the therapy that elevates general toxicity and systemic immunogenicity. To address these challenges, the focus of gene therapy for bone and cartilage repair has shifted in recent years to the use of autologous cells, typically osteocytes or chondrocytes, or their progenitors, transfected with therapeutic genes; the cells are cultivated in vitro before in vivo transplantation. These gene-enhanced therapeutic cells provide sustained autocrine/paracrine stimulation and localized gene expression. An important advantage of the cell-based approach is that factors contributing to off-target toxicity and immunogenicity are metabolically cleared during the in vitro incubation of the transfected cells prior to being administered to the transplant recipients. This review focuses on gene therapy approaches for treating bone and joint disorders, and specifically discusses the development of cell-based delivery approaches.

[Pathogenesis of liver fibrosis in patients with chronic hepatitis B].

OBJECTIVE: To explore the role of sinusoidal endothelial cell in the development of liver fibrosis, and to dissect the relationship among hepatic microcirculation disorders, hepatic sinusoidal capilarization and liver fibrosis. METHODS: Liver biopsy was performed in fifty-six patients with chronic hepatitis B. The liver tissues were observed under light microscope and transmitted electronic microscope. RESULTS: Of 56 cases, 39 cases were mild hepatitis, 10 were moderate hepatitis, and 7 were severe hepatitis. The morphology of hepatic stellate cells (HSCs) was similar to that of fibroblasts in the tissues of the patients with chronic hepatitis B. Collagenous fibers were deposited around the hepatic stellate cells. Electron-dense materials were deposited between sinusoidal endothelial cell and hepatic stellate cell. The size and amount of fenestraes of sinusoidal endothelial cells were reduced in 53 of 56 cases. The consecutive or inconsecutive membrane-like materials were observed along sinusoidal endothelial cells in 20 cases. Collagen fibers were observed in the space of Disse in 15 cases. Even in the patients with normal hepatic functions, red blood cells aggregation and microthrombi could be observed in the liver tissues. CONCLUSION: Sinusoidal endothelial cells are involved in development of liver fibrosis by interacting with hepatic stellate cells. Hepatic microcirculation disorders and sinusoidal capillarization are important changes in the early stage of liver fibrosis.

Gene transfer and living release of transforming growth factor-beta3 for cartilage tissue engineering applications.

Cartilage restoration continues to present a tremendous clinical challenge due to its nonvascular nature. Many studies have demonstrated that chondrogenesis of progenitor cells can be achieved in vitro by manual dose of growth factors; however, it remains a vital difficulty in feeding growth factors to implanted therapeutic cells in vivo. Herein, we constructed recombinant adenovirus encoding human transforming growth factor-beta3 (hTGF-beta3) and practiced it in rat bone marrow-derived mesenchymal stromal cells and articular chondrocytes for cartilage regeneration. Optimal viable transduction and transgenic hTGF-beta3 production were achieved; consequently, positive expression of cartilage marker-collagen type II was enabled in the infected progenitors. We thus conclude that recombinant adenovirus encoding TGF-beta3 gene has been successfully established and validated for cartilage tissue engineering applications.

TGF-beta3: A promising growth factor in engineered organogenesis.

BACKGROUND: Engineered organogenesis is one of the most challenging areas on the cutting edge of regenerative medicine. Growth factors can affect cell proliferation, migration and differentiation profoundly, and thus play a critical role in tissue regeneration. TGF-betas produce a wide range of effects in different cells and tissues. TGF-beta3 is relatively recently discovered and studied. OBJECTIVE: To provide a broader understanding of the current state of TGF-beta3 in engineered osteogenesis, chondrogenesis, palate development, scar-free wound healing, odontogenesis and neurogenesis. METHODS: This review summarizes studies that explore or apply TGF-beta3 for organogenesis with engineering methodology and a regenerative medical perspective. RESULTS/CONCLUSION: TGF-beta3 has proven to be a competent growth factor in engineered organogenesis in vitro. In recent years, using TGF-beta3, more and more in vivo studies have yielded significant therapeutic achievements in animal models, which bear much promise for future medical application.

RNA extraction from polysaccharide-based cell-laden hydrogel scaffolds.

An effective method for obtaining high-quality RNA from polysaccharide-rich hydrogels would be of great interest to biomaterialists and tissue engineers. Based on the similarities between polysaccharide-based hydrogels and plant tissues, we used a plant-specific RNA extraction kit to extract RNA from mammalian cells encapsulated in hydrogel scaffolds. The results indicate that this method can be reliably used in isolating high-purity RNA from polysaccharide hydrogels.