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With the emergence of antibiotic-resistant bacteria, innovative approaches are needed for the treatment of urinary tract infections. Boosting antimicrobial peptide expression may provide an alternative to antibiotics. Here, we developed reporter cell lines and performed a high-throughput screen of clinically used drugs to identify compounds that boost ribonuclease 4 and 7 expression (RNase 4 and 7), peptides that have antimicrobial activity against antibiotic-resistant uropathogens. This screen identified histone deacetylase (HDAC) inhibitors as effective RNase 4 and RNase 7 inducers. Validation studies in primary human kidney and bladder cells confirmed pan-HDAC inhibitors as well as the HDAC class I inhibitor, MS-275, induce RNase 4 and RNase 7 to protect human kidney and bladder cells from uropathogenic Escherichia coli . When we administered MS-275 to mice, RNase 4 and 7 expression increased and mice were protected from acute transurethral E. coli challenge. In support of this mechanism, MS-275 treatment increased acetylated histone H3 binding to the RNASE4 and RNASE7 promoters. Overexpression and knockdown of HDAC class I proteins identified HDAC3 as a primary regulator of RNase 4 and 7. These results demonstrate the protective effects of enhancing RNase 4 and RNase 7, opening the door to repurposing medications as antibiotic conserving therapeutics for urinary tract infection.

This study investigated the main mechanism and role of caspase-11/4 as a pattern recognition receptor (PRR) in periodontitis through caspase-11 inhibition.Clinical tissue samples were collected from patients with periodontitis and healthy volunteers and evaluated through hematoxylin-eosin (HE) staining, immunohistochemical (IHC) staining, and real-time quantitative PCR (RT-qPCR). In the rat periodontitis model, both these staining procedures, RT-qPCR, and western blotting were used to evaluate the histological, mRNA, and protein levels of caspase-11, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α). In vitro, the role of caspase-11, inhibited by siRNA, was investigated by analyzing the mRNA and protein levels of IL-1β and TNF-α in Porphylinomonas gingivalis (P. gingivalis) lipopolysaccharide (LPS)-stimulated Raw264.7 macrophages.Histological and molecular biological results of clinical and experimental animal periodontitis samples indicated that caspase-11/4 mRNA and protein levels significantly increased in inflammatory tissues. Caspase-11 is mainly distributed in leukocytes, which are labeled by CD45 in the submucosa. In vitro results further confirmed that the expression of caspase-11/4, IL-1β, and TNF-α significantly increased in LPS-stimulated macrophages, and these changes were significantly attenuated by inhibiting caspase-11/4 expression.The function of caspase-11 in rat periodontitis models is similar to that of caspase-4 in human clinical periodontitis. IL-1β and TNF-α release in periodontitis depends on the recognition of P. gingivalis LPS by caspase-11/4.

Congenital urinary tract obstruction (UTO) is the leading cause of chronic kidney disease in children; however, current management strategies do not safeguard against progression to end-stage renal disease, highlighting the need for interventions to limit or reverse obstructive nephropathy. Experimental UTO triggers renal urothelial remodeling that culminates in the redistribution of basal keratin 5-positive (Krt5+) renal urothelial cells (RUCs) and the generation of uroplakin-positive (Upk)+ RUCs that synthesize a protective apical urothelial plaque. The cellular source of Upk+ RUCs is currently unknown, limiting the development of strategies to promote renal urothelial remodeling as a therapeutic approach. In the present study, we traced the origins of adult Upk+ RUCs during normal development and in response to UTO. Fate mapping analysis demonstrated that adult Upk+ RUCs derive from embryonic and neonatal Krt5+ RUCs, whereas Krt5+ RUCs lose this progenitor capacity and become lineage restricted by postnatal day 14. However, in response to UTO, postnatal day 14-labeled adult Krt5+ RUCs break their lineage restriction and robustly differentiate into Upk+ RUCs. Thus, Krt5+ RUCs drive renal urothelial formation during normal ontogeny and after UTO by differentiating into Upk+ RUCs in a temporally restricted manner.

Infectious peritonitis is a common complication in patients undergoing chronic peritoneal dialysis (PD), limiting the duration of PD as a modality for renal replacement therapy and increasing patient morbidity and mortality. Antimicrobial peptides (AMPs) serve critical roles in mucosal defense, but their expression and activity during peritonitis are poorly understood. We hypothesized that AMPs belonging to the Ribonuclease (RNase) A Superfamily are present in peritoneal fluid and increase during peritonitis in patients undergoing chronic PD. In the absence of peritonitis, we detected RNase 3, RNase 6, and RNase 7 in cell-free supernatants and viable cells obtained from peritoneal fluid of chronic PD patients. The cellular sources of these RNases were eosinophils (RNase 3), macrophages (RNase 6), and mesothelial cells (RNase 7). During peritonitis, RNase 3 increased 55-fold and RNase 7 levels increased 3-fold on average, whereas RNase 6 levels were unchanged. The areas under the receiver-operating characteristic curves for RNase 3 and RNase 7 were 0.99 (95% confidence interval (CI): 0.96–1.0) and 0.79 (95% CI: 0.64–0.93), respectively, indicating their potential as biomarkers of peritonitis. Discrete omental reservoirs of these RNases were evident in patients with end stage kidney disease prior to PD initiation, and omental RNase 3 reactive cells increased in patients undergoing PD with a history of peritonitis. We propose that constitutive and inducible pools of antimicrobial RNases form a network to shield the peritoneal cavity from microbial invasion in patients undergoing chronic PD.

Urinary tract infections (UTIs) affect 150 million people worldwide. Uropathogenic Escherichia coli (UPEC) is the primary pathogen causing over 80% of UTIs. Systemic antibiotic treatment is the only available therapy for UTIs. Thus, novel non-antibiotic treatments for UTI are necessary. The NADPH oxidase complex 2 (NOX2) has an essential role in the antimicrobial response against many bacterial and fungal infections, but its role during UTIs remains unknown. Objective To study the role of NOX2 in bacterial killing during experimental UTI. Methods Female wild-type (WT) C57BL/6 mice, NOX2 knockout (KO) mice, and WT mice treated with a NOX2 inhibitor were transurethrally infected with UPEC (CFT073 strain). NOX2 protein expression was analyzed by Western blotting. Cellular sources of NOX2 were identified by immunofluorescence. Neutrophils were isolated from murine bone marrow. Human neutrophils were purified from peripheral blood of healthy donors. Purified neutrophils were infected with UPEC in vitro. UPEC burden was assessed by enumerating colony forming units (CFU). Reactive oxygen species (ROS) production was quantified using the Amplex™ Red kit. Results NOX2 KO mice, or mice treated with NOX2 inhibitor, were more susceptible to experimental UTI compared to WT mice. Immunofluorescence microscopy localized NOX2 primarily in infiltrating neutrophils. Neutrophils from NOX2 KO mice exhibited impaired extracellular ROS production and increased intracellular bacteria compared to WT controls, after challenged with UPEC in vitro. Similar effects occurred in human and murine neutrophils following chemical inhibition of NOX2 in vitro. Conclusion Neutrophil NOX2 serves a critical antimicrobial role during experimental UTI. Supported by grant from NIH (K01 DK128379-01)

People with diabetes mellitus have increased infection risk. With diabetes, urinary tract infection (UTI) is more common and has worse outcomes. Here, we investigate how diabetes and insulin resistance impact the kidney’s innate defenses and urine sterility. We report that type 2 diabetic mice have increased UTI risk. Moreover, insulin-resistant prediabetic mice have increased UTI susceptibility, independent of hyperglycemia or glucosuria. To identify how insulin resistance affects renal antimicrobial defenses, we genetically deleted the insulin receptor in the kidney’s collecting tubules and intercalated cells. Intercalated cells, located within collecting tubules, contribute to epithelial defenses by acidifying the urine and secreting antimicrobial peptides (AMPs) into the urinary stream. Collecting duct and intercalated cell–specific insulin receptor deletion did not impact urine acidification, suppressed downstream insulin-mediated targets and AMP expression, and increased UTI susceptibility. Specifically, insulin receptor–mediated signaling regulates AMPs, including lipocalin 2 and ribonuclease 4, via phosphatidylinositol-3-kinase signaling. These data suggest that insulin signaling plays a critical role in renal antibacterial defenses.

The signaling networks regulating antimicrobial activity during urinary tract infection (UTI) are incompletely understood. Interleukin-6 (IL-6) levels increase with UTI severity, but the specific contributions of IL-6 to host immunity against bacterial uropathogens are unknown. To clarify this we tested whether IL-6 activates the Stat3 transcription factor, to drive a program of antimicrobial peptide gene expression in infected urothelium during UTI. Transurethral inoculation of uropathogenic Escherichia coli led to IL-6 secretion, urothelial Stat3 phosphorylation, and activation of antimicrobial peptide transcription, in a Toll-like receptor 4–dependent manner in a murine model of cystitis. Recombinant IL-6 elicited Stat3 phosphorylation in primary urothelial cells in vitro , and systemic IL-6 administration promoted urothelial Stat3 phosphorylation and antimicrobial peptide expression in vivo . IL-6 deficiency led to decreased urothelial Stat3 phosphorylation and antimicrobial peptide mRNA expression following UTI, a finding mirrored by conditional Stat3 deletion. Deficiency in IL-6 or Stat3 was associated with increased formation of intracellular bacterial communities, and exogenous IL-6 reversed this phenotype in IL-6 knockout mice. Moreover, chronic IL-6 depletion led to increased renal bacterial burden and severe pyelonephritis in C3H/HeOuJ mice. Thus, IL-6/Stat3 signaling drives a transcriptional program of antimicrobial gene expression in infected urothelium, with key roles in limiting epithelial invasion and ascending infection.

Considering the critical role eye contact [1] plays in our daily interaction, we propose a non-invasive approach and implement it with computer vision as a comprehensive eye contact detection system. Our system does not need additional hardware and calibration. It consists of a regression gaze direction CNN model — VHModel — and a binary eye contact detection model, and they are both trained on the Columbia-Gaze dataset. Experiment shows that our proposed approach can achieve an MCC score of 0.92 on the average, which is higher than competing methods. To verify the generalization ability of our system, we collect a new eye contact dataset, which contains 2.2K images of various head poses and eye scales. Our system still achieves an accuracy up to 0.80 on this dataset. Through the comparisons, we conclude that our system is robust to changes in environment, face, illumination, head pose and distance.

Background Evidence suggests that antimicrobial peptides, components of the innate immune response, protect the kidneys and bladder from bacterial challenge. We previously identified ribonuclease 7 (RNase 7) as a human antimicrobial peptide that has bactericidal activity against uropathogenic Escherichia coli (UPEC). Functional studies assessing RNase 7's contributions to urinary tract defense are limited. Methods To investigate RNase 7's role in preventing urinary tract infection (UTI), we quantified urinary RNase 7 concentrations in 29 girls and adolescents with a UTI history and 29 healthy female human controls. To assess RNase 7's antimicrobial activity in vitro in human urothelial cells, we used siRNA to silence urothelial RNase 7 production and retroviral constructs to stably overexpress RNase 7; we then evaluated UPEC's ability to bind and invade these cells. For RNase 7 in vivo studies, we developed humanized RNase 7 transgenic mice, subjected them to experimental UTI, and enumerated UPEC burden in the urine, bladder, and kidneys. Results Compared with controls, study participants with a UTI history had 1.5-fold lower urinary RNase 7 concentrations. When RNase 7 was silenced in vitro, the percentage of UPEC binding or invading human urothelial cells increased; when cells overexpressed RNase 7, UPEC attachment and invasion decreased. In the transgenic mice, we detected RNase 7 expression in the kidney's intercalated cells and bladder urothelium. RNase 7 humanized mice exhibited marked protection from UPEC. Conclusions These findings provide evidence that RNase 7 has a role in kidney and bladder host defense against UPEC and establish a foundation for investigating RNase 7 as a UTI prognostic marker or nonantibiotic-based therapy.

Urinary tract infection (UTI) is one of the most common ailments requiring both short-term and prophylactic antibiotic therapies. Progression of infection from the bladder to the kidney is associated with more severe clinical symptoms (e.g., fever and vomiting) as well as with dangerous disease sequelae (e.g., renal scaring and sepsis). Host-pathogen interactions that promote bacterial ascent to the kidney are not completely understood. Prior studies indicate that the magnitude of proinflammatory cytokine elicitation in vitro by clinical isolates of uropathogenic Escherichia coli (UPEC) inversely correlates with the severity of clinical disease. Therefore, we hypothesize that the magnitude of initial proinflammatory responses during infection defines the course and severity of disease. Clinical UPEC isolates obtained from patients with a nonfebrile UTI elicited high systemic proinflammatory responses early during experimental UTI in a murine model and were attenuated in bladder and kidney persistence. Conversely, UPEC isolates obtained from patients with febrile UTI elicited low systemic proinflammatory responses early during experimental UTI and exhibited prolonged persistence in the bladder and kidney. Soluble factors in the supernatant from saturated cultures as well as the lipopolysaccharide (LPS) serotype correlated with the magnitude of proinflammatory responses in vitro . Our data suggest that the structure of the O-antigen sugar moiety of the LPS may determine the strength of cytokine induction by epithelial cells. Moreover, the course and severity of disease appear to be the consequence of the magnitude of initial cytokines produced by the bladder epithelium during infection. IMPORTANCE The specific host-pathogen interactions that determine the extent and course of disease are not completely understood. Our studies demonstrate that modest changes in the magnitude of cytokine production observed using in vitro models of infection translate into significant ramifications for bacterial persistence and disease severity. While many studies have demonstrated that modifications of the LPS lipid A moiety modulate the extent of Toll-like receptor 4 (TLR4) activation, our studies implicate the O-antigen sugar moiety as another potential rheostat for the modulation of proinflammatory cytokine production.

The L2-normalization and feature pooling have a wide range of applications in image classification and have also achieved remarkable results. However, there is much room for the existing descriptors which are extracted from pre-trained Convolutional Neural Network (CNN) models, to meet the requirement of precision for patch classification. We generate CNN descriptors by using L2-normalization and feature pooling on the existing pre-trained CNN descriptors. By evaluation on the Brown dataset, the mean Average Precision (mAP) of descriptor, which is based on Inception-v3 model that applies both L2-normalization and feature pooling, reaches 99.27%, 98.97% and 98.02% in three sub-datasets. Compared with the pre-trained CNN descriptors without L2-normalization and feature pooling, the mAP of pre-trained CNN descriptors can be respectively increased by $1.41 \% \sim 17.31 \%, 3.11 \% \sim 17.99 \%$ . $1.19\%\sim15.24\%$ . According to the experimental results, it is obvious that L2-normalization and feature pooling are beneficial to improve the performance of pre-trained CNN descriptors.

Urinary tract obstruction represents a common cause of kidney injury across the human life span, resulting in chronic kidney disease and end-stage renal disease. Yet, the extent of obstructive renal damage can be heterogeneous between individuals, implying the existence of unknown mechanisms that protect against or accelerate kidney injury. In this study, we investigated the role of urothelial remodeling in renal adaptation during congenital and acquired obstruction. In the Megabladder ( Mgb−/−) model of congenital obstruction and unilateral ureteral ligation model of acute obstruction, progressive hydronephrosis is strongly associated with dynamic reorganization of the renal urothelium, which elaborates a continuous uroplakin (Upk) plaque. This led us to postulate that the Upk plaque prevents parenchymal injury during urinary tract obstruction. To test this hypothesis, we interbred Mgb−/− and Upk1b−/− mice, which lack the critical Upk1b subunit for Upk plaque formation. Upk1b−/−; Mgb−/− mice experienced an accelerated onset of bilateral hydronephrosis with severe (>67%) parenchymal loss, leading to renal failure and mortality in adolescence. To investigate the function of the renal Upk plaque during acute obstruction, we destabilized the Upk plaque by Upk1b deletion or genetically depleted Upk+ cells following unilateral ureteral obstruction. Both of these strategies accelerated renal parenchymal loss following ureteral ligation, attesting to a conserved, stabilizing role for Upk plaque deposition in the acutely obstructed kidney. In aggregate, these complementary experiments provide the first evidence that the Upk plaque confers an essential, protective adaptation to preserve renal parenchymal integrity during congenital and acquired urinary tract obstruction.

Recent evidence suggests antimicrobial peptides protect the urinary tract from infection. Ribonuclease 7 (RNase 7), a member of the RNase A superfamily, is a potent epithelial-derived protein that maintains human urinary tract sterility. RNase 7 expression is restricted to primates, limiting evaluation of its antimicrobial activity in vivo . Here we identified ribonuclease 6 (RNase 6) as the RNase A superfamily member present in humans and mice that is most conserved at the amino acid level relative to RNase 7. Like RNase 7, recombinant human and murine RNase 6 has potent antimicrobial activity against uropathogens. Quantitative real-time PCR and immunoblot analysis indicate that RNase 6 mRNA and protein are upregulated in the human and murine urinary tract during infection. Immunostaining located RNase 6 to resident and infiltrating monocytes, macrophages, and neutrophils. Uropathogenic E. coli induces RNase 6 peptide expression in human CD14 + monocytes and murine bone marrow–derived macrophages. Thus, RNase 6 is an inducible, myeloid-derived protein with markedly different expression from the epithelial-derived RNase 7 but with equally potent antimicrobial activity. Our studies suggest RNase 6 serves as an evolutionarily conserved antimicrobial peptide that participates in the maintenance of urinary tract sterility.

In this work, two series of cyclic siloxane tetramers based on polysiloxane, cholesterol derivate monomer, and biphenyl derivate monomer were designed and synthesized to investigate the effect of the length of flexible spacer and cholesteric monomer percentage (Xchol) on their mesogenic properties. Results revealed that the tetramers exhibited thermotropic liquid crystalline behaviors and their properties were influenced by various factors. With Xchol increased, abundant mesophases for the tetramers could be observed and their mesogenic temperature ranges were generally widened. Significant effect of the flexible spacer length on the transition temperatures was also found and discussed. Interestingly, blue phases could be easily observed for those tetramers containing more than 50.0 mol% chiral mesogen, and the temperature ranges of blue phase increased with the increasing of Xchol whereas reduced with the decreasing of length of flexible spacer. Moreover, the thermo-optical properties and helical twisting power of the tetramers were also investigated.

Several kinds of tolane cyano derivatives with different lateral fluoro substituents are doped with chiral additives to induce the blue phase (BP). Fluoro substituents are found to exert a great effect on the BP ranges for biphenyl mesogens. The laterally difluorinated compounds exhibit wider BP ranges than their corresponding mono-fluorinated homologues when equal chiral dopant is added, while the non-fluorinated compounds show direct isotropic (Iso) to chiral nematic (N*) transitions, even in highly chiral systems. By adjusting the concentrations of the chiral dopant ISO(6OBA)2 in the fluorinated liquid crystals, the BP ranges can be broadened to more than 12 °C. Competition between the steric repulsions caused by the lateral fluoro substituents and π–π interactions of the aromatic cores is supposed to be the main factor that leads to the above results. Apart from this, a weak C–H⋯F interaction may have also been conducive to the BP stabilization.

Acquired renal scarring occurs in a subset of patients following febrile urinary tract infections and is associated with hypertension, proteinuria, and chronic kidney disease. Limited knowledge of histopathology, immune cell recruitment, and gene expression changes during pyelonephritis restricts the development of therapies to limit renal scarring. Here, we address this knowledge gap using immunocompetent mice with vesicoureteral reflux. Transurethral inoculation of uropathogenic Escherichia coli in C3H/HeOuJ mice leads to renal mucosal injury, tubulointerstitial nephritis, and cortical fibrosis. The extent of fibrosis correlates most significantly with inflammation at 7 and 28 days postinfection. The recruitment of neutrophils and inflammatory macrophages to infected kidneys is proportional to renal bacterial burden. Transcriptome analysis reveals molecular signatures associated with renal ischemia-reperfusion injury, immune cell chemotaxis, and leukocyte activation. This murine model recapitulates the cardinal histopathological features observed in humans with acquired renal scarring following pyelonephritis. The integration of histopathology, quantification of cellular immune influx, and unbiased transcriptional profiling begins to define potential mechanisms of tissue injury during pyelonephritis in the context of an intact immune response. The clear relationship between inflammatory cell recruitment and fibrosis supports the hypothesis that acquired renal scarring arises as a consequence of excessive host inflammation and suggests that immunomodulatory therapies should be investigated to reduce renal scarring in patients with pyelonephritis.

The photocontrolled phase transitions and reflection behaviors of a smectic liquid crystal, 4-octyl-4'-cyanobiphenyl (8CB), tuned by a chiral azobenzene, are systematically investigated. For the smectic 8CB doped with the chiral azobenzene (1R)-(-)-4-n-hexyl-4'-menthylazobenzene (ABE), the initial smectic phase can be switched to cholesteric and then to isotropic upon UV irradiation due to the trans-to-cis photoisomerization of ABE; however, no reflection band is observed. For the smectic 8CB doped with ABE and the chiral agent (S)-(-)-1,1'-binaphthyl-2,2'-diol (BN), a reflection band located in the short-wavelength infrared region is observed, which disappears after further UV irradiation. For the smectic 8CB doped with ABE and a chiral agent with higher helical twisting power, (S)-2,2'-methylendioxy-1,1'-binaphthalene (DBN), a phototunable system with cholesteric pitch short enough to reflect visible light is demonstrated. With a given concentration of the chiral dopant DBN, a reversible reflection color transition is realized tuned by the isomerization of azobenzene. The reverse phase transition from isotropic to cholesteric and then to smectic can be recovered upon visible irradiation. The photocontrolled phase transitions in smectic liquid crystals and the corresponding changes in reflection band switched by photoisomerization of azobenzene may provide impetus for their practical application in optical memories, displays, and switches.

We hypothesized that virulence levels of Escherichia coli isolates causing pediatric urinary tract infections differ according to severity of infection and also among various uropathies known to contribute to pediatric urinary tract infections. We evaluated these relationships using in vitro cytokine interleukin-6 elicitation.E. coli isolates were cultured from children presenting with urinary tract infections. In vitro cytokine (interleukin-6) elicitation was quantified for each isolate and the bacteria were grouped according to type of infection and underlying uropathy (neurogenic bladder, nonneurogenic bowel and bladder dysfunction, primary vesicoureteral reflux, no underlying etiology).A total of 40 E. coli isolates were collected from children with a mean age of 61.5 months (range 1 to 204). Mean level of in vitro cytokine elicitation from febrile urinary tract infection producing E. coli was significantly lower than for nonfebrile strains (p = 0.01). The interleukin-6 response to E. coli in the neurogenic bladder group was also significantly higher than in the vesicoureteral reflux (p = 0.01) and no underlying etiology groups (p = 0.02).In vitro interleukin-6 elicitation, an established marker to determine bacterial virulence, correlates inversely with clinical urinary tract infection severity. Less virulent, high cytokine producing E. coli were more likely to cause cystitis and were more commonly found in patients with neurogenic bladder and nonneurogenic bowel and bladder dysfunction, whereas higher virulence isolates were more likely to produce febrile urinary tract infections and to affect children with primary vesicoureteral reflux and no underlying etiology. These findings suggest that bacteria of different virulence levels may be responsible for differences in severity of pediatric urinary tract infections and may vary among different underlying uropathies.

Thiophene-based bent-shaped mesogens were firstly applied to extend the blue phase range. And the electro-optical performances of liquid crystalline composites doped with different concentration of these bent-shaped mesogens were also explored by incorporating in-plane electric field geometry.

Urinary tract infections (UTIs) represent one of the most commonly acquired diseases among the general population as well as hospital in-patients, yet remain difficult to effectively and consistently treat. High rates of recurrence, anatomic abnormalities, and functional disturbances of the urinary tract all contribute to the difficulty in management of these infections. However, recent advances reveal important molecular and genetic factors that contribute to bacterial invasion and persistence in the urinary tract, particularly for the most common causative agent, uropathogenic Escherichia coli. Recent studies using animal models of experimental UTIs have recently provided mechanistic insight into the clinical observations that question the effectiveness of antibiotic therapy in treatment. Ultimately, continuing research will be necessary to identify the best targets for effective treatment of this costly and widespread infectious disease.

Bacteria that cause chronic and/or recurrent diseases often rely on a biofilm lifestyle. The foundation of the biofilm structure is the extracellular polymeric substance (EPS) that acts as a barrier to both effectors of the immune system and antimicrobial agents. Recent work has highlighted extracellular DNA (eDNA) as a key component common to many pathogenic biofilms. Here, we show that the DNABII family of proteins, well known for their strong structural influences on intracellular DNA, was also critical for the integrity of the EPS matrix of biofilms that contain eDNA. In fact, antisera derived against a purified Escherichia coli DNABII family member rapidly disrupts the biofilm EPS formed by multiple human pathogens in vitro. In addition, when a member of this family of proteins was used as an immunogen in an animal model in which the bacteria had already formed a robust biofilm at the site of infection, the resultant targeted immune response strongly ameliorated this biofilm disease in vivo. Finally, this methodology to debulk the biofilm of EPS was shown to work synergistically with otherwise ineffective traditional anti-microbial approaches in vitro. We discuss the prospects for targeting DNABII family members as a potential universal strategy for treating biofilm diseases.

The usefulness of prophylactic antibiotics to prevent recurrent urinary tract infections in children was recently questioned. Some groups have attempted to use probiotics, most commonly lactobacillus, to prevent recurrent infections by altering the intestinal bacterial reservoir with variable results. Mutaflor® is a possible alternative probiotic in which the active agent is Nissle 1917. Nissle 1917 is a commensal Escherichia coli strain that eradicates pathogenic bacteria from the gastrointestinal tract. Due to its ability to alter the intestinal biome we hypothesized that Mutaflor may have the potential to prevent recurrent urinary tract infections. Thus, we used an in vitro assay to analyze the effectiveness of Nissle 1917 for eradicating pediatric uropathogens.We established a collection of 43 bacterial pediatric uropathogens. With each isolate a microcin-type assay was performed to determine the effectiveness of Nissle 1917 on bacterial growth inhibition and competitive overgrowth.Nissle 1917 adversely affected the growth of 34 of the 43 isolates (79%) isolates. It inhibited the growth of 21 isolates and overgrew 13. The percent of species adversely affected by Nissle 1917 was 40% for Pseudomonas, 50% for E. coli, Enterococcus and Staphylococcus, 100% for Klebsiella and Enterobacter, and 0% for Citrobacter and Serratia.Nissle 1917, the active agent in Mutaflor, inhibited or out competed most bacterial isolates. These mechanisms could be used in vivo to eradicate uropathogens from the gastrointestinal tract. Further study is needed to determine whether Mutaflor can prevent recurrent urinary tract infections in children.

Bcr/abl fusion gene is the marker gene in chronic myelogenous leukemia (CML) and becomes the target for CML therapy. Although Imatinib opened a new way to treat CML, the resistance to the drug caused by bcr/abl fusion protein mutation stimulated search for new molecules to inhibit bcr/abl expression. In our research, it was found that a novel 2-aminosteroid (H89465) possessed special mechanism in treating CML. H89465 inhibits the proliferation of both non-resistant and resistant CML cells such as K562, Meg-01 and clinical primary CML cells. It prolongs the survival time of NOD/SCID mice inoculated with K562 leukemia cells. The mechanism underlying the effects is concerned with down-regulation of bcr/abl mRNA expression followed by decreasing the BCR/ABL protein expression and tyrosine kinase activity in CML cells. Our results demonstrate that H89465 possesses the therapeutic potential in treating human CML.

Diabetes mellitus is a systemic disease associated with a deficiency of insulin production or action. Diabetic patients have an increased susceptibility to infection with the urinary tract being the most common site of infection. Recent studies suggest that Ribonuclease 7 (RNase 7) is a potent antimicrobial peptide that plays an important role in protecting the urinary tract from bacterial insult. The impact of diabetes on RNase 7 expression and function are unknown. Here, we investigate the effects of insulin on RNase 7. Using human urine specimens, we measured urinary RNase 7 concentrations in healthy control patients and insulin-deficient type 1 diabetics before and after starting insulin therapy. Compared to controls, diabetic patients had suppressed urinary RNase 7 concentrations, which increased with insulin. Using primary human urothelial cells, we explored the mechanisms by which insulin induces RNase 7. Insulin induces RNase 7 production via the phosphatidylinositide 3-kinase signaling pathway (PI3K/AKT) to shield urothelial cells from uropathogenic E. coli. In contrast, we show that uropathogenic E. coli suppresses PI3K/AKT and RNase 7. Together, these results indicate that insulin and PI3K/AKT signaling are essential for RNase 7 expression. They also suggest that increased infection risks in diabetic patients may be secondary to suppressed RNase 7 production. These data may provide unique insight into novel UTI therapeutic strategies in at risk populations.

Summary Introduction Control of bacteriuria is problematic in patients who perform clean intermittent catheterization for management of neurogenic bladder. This population is often burdened with multiple urinary tract infections (UTIs), placing them at increased risk of end-stage renal disease. Hydrophilic catheters are a potential way to improve smooth and clean insertion, reduce disruption of the urothelium, and reduce bacterial colonization. Objective The goal of the study was to compare the type and virulence of microorganisms recovered from the urine of patients that use either a hydrophilic or conventional polyvinyl chloride (PVC) catheter. Methods Fifty patients with an underlying diagnosis of myelomeningocele were recruited for a 12-month prospective, randomized, investigator-blinded study. Twenty-five patients were allocated to the hydrophilic catheter intervention, and 25 continued use of a PVC catheter. Cultures were performed on urine obtained by catheterization at enrollment, and 3, 6, and 12 months. Bacterial species were assigned a designation as either potentially pathogenic or non-pathogenic. Escherichia coli isolates were the most predominant and were serotyped to further stratify the pathogenicity of the strains. Lastly, patients were surveyed at enrollment, and at the two later time points evaluating their current catheter for satisfaction. Results A total of 232 different bacterial isolates were obtained from the 182 collected urine cultures. In addition, seven species were recovered from the two UTI reported during the study period. Bacterial growth was not detected in 29 of the samples (16%). Although not statistically significant, collectively there was a 40% decrease in the average number of potentially pathogenic species recovered from those patients using hydrophilic catheters (0.81 per urine sample) compared with PVC catheter use (1.24 per urine sample). Since E. coli species can be either pathogenic or non-pathogenic, we examined 14 of the most commonly implicated serotypes associated with uropathogenic E. coli (UPEC). We identified the serotype of 57% of E. coli strains recovered. There was a trend for the recovery of fewer UPEC serotypes from the hydrophilic group (54% hydrophilic verses 64% PVC), further suggesting that the catheter type may influence the microbiological milieu. Although no significant differences were reported in patient satisfaction, almost half of the patients from the hydrophilic catheter cohort continue use of this type of catheter. Conclusions There was a trend for reduced recovery of potentially pathogenic bacteria with the use of hydrophilic catheters. The reduction in potentially pathogenic species will reduce antibiotic exposures and some patients may prefer the comfort hydrophilic catheters provide. Download : Download high-res image (535KB) Download : Download full-size image Figure . Overview of the study. Fifty myelomeningocele patients were randomized to either the intervention of using a hydrophilic catheter for 12 months or to continue their PCV catheter; urine cultures were examined at 3-month intervals. At the end of the study, hydrophilic catheter users had fewer potential pathogenic species recovered from their cultures. Some individuals preferred the new catheters so much so they switched indefinitely.

Background The role of calcium oxalate crystals and deposits in UTI pathogenesis has not been established. The objectives of this study were to identify bacteria present in pediatric urolithiasis and, using in vitro and in vivo models, to determine the relevance of calcium oxalate deposits during experimental pyelonephritis. Methods Pediatric kidney stones and urine were collected and both cultured and sequenced for bacteria. Bacterial adhesion to calcium oxalate was compared. Murine kidney calcium oxalate deposits were induced by intraperitoneal glyoxalate injection and kidneys were transurethrally inoculated with uropathogenic Escherichia coli to induce pyelonephritis Results E. coli of the family Enterobacteriaceae was identified in patients by calcium oxalate stone culture. Additionally Enterobacteriaceae DNA was sequenced from multiple calcium oxalate kidney stones. E. coli selectively aggregated on and around calcium oxalate monohydrate crystals. Mice inoculated with glyoxalate and uropathogenic E. coli had higher bacterial burdens, increased kidney calcium oxalate deposits and an increased kidney innate immune response compared to mice with only calcium oxalate deposits or only pyelonephritis. Conclusions In a murine model, the presence of calcium oxalate deposits increases pyelonephritis risk, likely due to preferential aggregation of bacteria on and around calcium oxalate crystals. When both calcium oxalate deposits and uropathogenic bacteria were present, calcium oxalate deposit number increased along with renal gene transcription of inner stone core matrix proteins increased. Therefore renal calcium oxalate deposits may be a modifiable risk factor for infections of the kidney and urinary tract. Furthermore, bacteria may be present in calcium oxalate deposits and potentially contribute to calcium oxalate renal disease.