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Nephrotic syndrome is characterized by severe proteinuria, hypoalbuminaemia, edema and hyperlipidaemia. Genetic studies of nephrotic syndrome have led to the identification of proteins playing a crucial role in slit diaphragm signaling, regulation of actin cytoskeleton dynamics and cell-matrix interactions. The laminin α5 chain is essential for embryonic development and, in association with laminin β2 and laminin γ1, is a major component of the glomerular basement membrane, a critical component of the glomerular filtration barrier. Mutations in LAMA5 were recently identified in children with nephrotic syndrome. Here, we have identified a novel missense mutation (E884G) in the uncharacterized L4a domain of LAMA5 where homozygous mice develop nephrotic syndrome with severe proteinuria with histological and ultrastructural changes in the glomerulus mimicking the progression seen in most patients. The levels of LAMA5 are reduced in vivo and the assembly of the laminin 521 heterotrimer significantly reduced in vitro. Proteomic analysis of the glomerular extracellular fraction revealed changes in the matrix composition. Importantly, the genetic background of the mice had a significant effect on aspects of disease progression from proteinuria to changes in podocyte morphology. Thus, our novel model will provide insights into pathologic mechanisms of nephrotic syndrome and pathways that influence the response to a dysfunctional glomerular basement membrane that may be important in a range of kidney diseases.

Staphylococcus aureus biofilms are a significant problem in health care settings, partly due to the presence of a nondividing, antibiotic-tolerant subpopulation. Here we evaluated treatment of S. aureus UAMS-1 biofilms with HT61, a quinoline derivative shown to be effective against nondividing Staphylococcus spp. HT61 was effective at reducing biofilm viability and was associated with increased expression of cell wall stress and division proteins, confirming its potential as a treatment for S. aureus biofilm infections.

Early stages of geographic atrophy (GA) age-related macular degeneration is characterised by the demise of photoreceptors, which precedes the loss of underlying retinal pigment epithelial (RPE) cells. Sight-loss due to GA has no effective treatment; reflecting both the complexity of the disease and the lack of suitable animal models for testing potential therapies. We report the development and characterisation of a laser-induced mouse model with early GA-like pathology. Retinas were lasered at adjacent sites using a 810 nm laser (1.9 J/spot), resulting in the development of confluent, hypopigmented central lesions with well-defined borders. Optical Coherence Tomography over 2-months showed progressive obliteration of photoreceptors with hyper-reflective outer plexiform and RPE/Bruch’s membrane (BrM) layers within lesions, but an unaffected inner retina. Light/electron microscopy after 3-months revealed lesions without photoreceptors, leaving the outer plexiform layer apposed to the RPE. We observed outer segment debris, hypo/hyperpigmented RPE, abnormal apical-basal RPE surfaces and BrM thickening. Lesions had wedge-shaped margins, extended zones of damage, activated Müller cells, microglial recruitment and functional retinal deficits. mRNA studies showed complement and inflammasome activation, microglial/macrophage phagocytosis and oxidative stress providing mechanistic insights into GA. We propose this mouse model as an attractive tool for early GA studies and drug-discovery.

A lectotype is designated for the Tibetan species Deronectes emmerichi Falkenström, 1936 (Currently Boreonectes emmerichi (Falkenström)), and its habitus, as well as the median lobe and parameres of its aedeagus, are figured along with additional comparative material. Material of Boreonectes emmerichi from Sikkim (BMNH) represents the first record of a Boreonectes Angus, 2010 species from India. The karyotype of Boreonectes emmerichi is described as having 26 pairs of autosomes plus sex chromosomes which are X0 (♂), XX (♀). The karyotype is most like that of Boreonectes macedonicus (Géuorguiev, 1959), but with slight differences. Additional chromosomal information is given for Boreonectes griseostriatus griseostriatus (De Geer, 1774) in the French Alps, Boreonectes griseostriatus strandi (Brinck, 1943) on the Kola Peninsula, Boreonectes multilineatus (Falkenström, 1922) in the Pyrenees and Boreonectes ibericus (Dutton & Angus, 2007) in the Spanish Picos de Europa.

open access article Non-typeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that plays a major role in a number of respiratory tract infections, including otitis media, cystic fibrosis and chronic obstructive pulmonary disease. Biofilm formation has been implicated in both NTHi colonization and disease, and is responsible for the increased tolerance of this pathogen towards antibiotic treatment. Targeting metabolic pathways that are important in NTHi biofilm formation represents a potential strategy to combat this antibiotic recalcitrance. A previous investigation demonstrated increased expression of a putative D-methionine uptake protein following exposure of NTHi biofilms to the ubiquitous signalling molecule, nitric oxide. We therefore hypothesized that treatment with exogenous D-methionine would impact on NTHi biofilm formation and increase antibiotic sensitivity. Treatment of NTHi during the process of biofilm formation resulted in a reduction in biofilm viability, increased biomass, changes in the overall biofilm architecture and the adoption of an amorphous cellular morphology. Quantitative proteomic analyses identified 124 proteins that were differentially expressed following D-methionine treatment, of which 51 (41 %) were involved in metabolic and transport processes. Nine proteins involved in peptidoglycan synthesis and cell division showed significantly increased expression. Furthermore, D-methionine treatment augmented the efficacy of azithromycin treatment and highlighted the potential of D-methionine as an adjunctive therapeutic approach for NTHi biofilm-associated infections.

A 2-year-old patient with a neuroblastoma developed haemolytic uraemic syndrome (HUS) following treatment with cisplatin and carboplatin. Following treatment with eculizumab, there was a substantial improvement in renal function with the recovery of the platelet count and the cessation of haemolysis. Subsequent investigations showed a novel, heterozygous CD46 splice site mutation with reduced peripheral blood neutrophil CD46 expression. Withdrawal of eculizumab was followed by the recurrence of disease activity, which resolved with re-introduction of therapy. Abnormal regulation of complement may be associated with other cases of cisplatin-induced HUS and treatment with eculizumab may be appropriate for other affected individuals.

Background: The role of Propionibacterium acnes in shoulder arthroplasty and broadly in orthopaedic prosthetic infections (PIs) has historically been underestimated, with biofilm formation identified as a key virulence factor attributed to invasive isolates. With an often indolent clinical course, P. acnes infection can be difficult to detect and treat. The present study investigates absorbable cements loaded with a broad-spectrum antibiotic combination as an effective preventative strategy to combat P. acnes biofilms.Methods: P. acnes biofilm formation on an unloaded synthetic calcium sulfate (CaSO4) bone void filler cement bead was evaluated by scanning electron microscopy (SEM) over 14 days. Beads loaded with tobramycin alone, vancomycin alone (as comparative controls) and a vancomycin & tobramycin dual treatment were assessed for their ability to eradicate planktonic P. acnes, prevent biofilm formation and eradicate preformed biofilms was also evaluated using viable cell counts, confocal microscopy and SEM.Results: P. acnes surface colonisation and biofilm formation on unloaded CaSO4 beads was slow. Beads loaded with antibiotics were able to kill planktonic cultures of 106 CFU/ml, prevent bacterial colonisation and significantly reduce biofilm formation over periods of weeks. Complete eradication of established biofilms was achieved with a contact time of one week.Conclusions: This study demonstrates that antibiotic-loaded CaSO4 beads may represent an effective antibacterial and antibiofilm strategy to combat PIs in which P. acnes is involved.Level of Evidence: Basic Science Study

SummaryA girl aged 6 presented with haematuria and her sister (aged 5) presented with haematuria and proteinuria. Family history showed multiple individuals suffering from end stage renal failure from the paternal side of the pedigree. Following kidney biopsy in the father and paternal grandmother, the pathological diagnosis was of focal segmental glomerulosclerosis (FSGS). Exome sequencing was undertaken in the proband's sister and grandmother. Genetic variants shared by both affected individuals were interrogated to identify the genetic cause of disease. Candidate variants were then sequenced in all the family members to determine segregation with the disease. A mutation of COL4A5 known to cause Alport syndrome segregated with disease from the paternal side of the pedigree and a variant in NPHS1 was present in both paediatric cases and inherited from their mother. This study highlights the advantages of exome sequencing over single gene testing; disease presentation can be heterogeneous with several genes representing plausible candidates; candidate gene(s) may be unavailable as a diagnostic test; consecutive, single gene testing typically concludes once a single causal mutation is identified. In this family, we were able to confirm a diagnosis of Alport syndrome, which will facilitate testing in other family members.

Atypical haemolytic uraemic syndrome (aHUS) is caused by dysregulated complement activation. A humanised anti-C5 monoclonal antibody has recently become available for treatment of this conditionWe present the first description of an infant with an activating mutation of complement factor B successfully treated with eculizumab. On standard doses she had evidence of ongoing C5 cleavage despite a good clinical response.Eculizumab is effective therapy for aHUS associated with factor B mutations, but recommended doses may not be adequate for all patients.

Background & Aims: Confocal endomicroscopy is an emerging technology that poses the endoscopist with challenges for identifying epithelial structures in the human intestine. We have shown previously that the murine intestinal epithelium is punctuated by gaps caused by cell shedding. The goals of this study were to determine if confocal endomicroscopy could resolve the presence of human epithelial gaps and whether a proinflammatory cytokine could increase cell shedding. Methods: Intestinal mucosa was imaged after staining with acriflavine. Confocal endomicroscopy of 17 patients yielded 6277 images from the human terminal ileum and rectum. Results were validated by parallel studies of anesthetized mice (wild-type and Math1 ΔIntestine ) using rigid confocal probe microscopy, 2-photon/confocal microscopy, and scanning electron microscopy. Results: Human terminal ileal and rectal epithelium revealed unstained areas with the diameter of an individual epithelial cell, with 2 distinct morphologies. One had a "target" appearance, shown by mouse studies to be goblet cells. The other morphology had no nucleus and was observed by rigid confocal probe microscopy and scanning electron microscopy in the villi of Math1 ΔIntestine mice, which lack goblet cells. In the mouse, tumor necrosis factor α (0.33 μg/g intraperitoneally) increases cell shedding by 27-fold and caused loss of barrier function across 20% of resultant gaps. Conclusions: Confocal endomicroscopy can distinguish between epithelial discontinuities (gaps) and goblet cells in human intestine. Results suggest that the sealing of epithelial gaps must be considered as a component of the intestinal barrier and has potential implications for intestinal barrier dysfunction in human disease.