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Shiga toxin (Stx)-producing enterohemorrhagiciEscherichia coli/i(EHEC) cause gastrointestinal infection and, in severe cases, hemolytic uremic syndrome which may lead to death. There is, to-date, no therapy for this infection. Stx induces ATP release from host cells and ATP signaling mediates its cytotoxic effects. Apyrase cleaves and neutralizes ATP and its effect on Stx and EHEC infection was therefore investigated. Apyrase decreased bacterial RecA and dose-dependently decreased toxin release fromiE. coli/iO157:H7iin vitro/i, demonstrated by reduced phage DNA and protein levels. The effect was investigated in a mouse model ofiE. coli/iO157:H7 infection. BALB/c mice infected with Stx2-producingiE. coli/iO157:H7 were treated with apyrase intraperitoneally, on days 0 and 2 post-infection, and monitored for 11 days. Apyrase-treated mice developed disease two days later than untreated mice. Untreated infected mice lost significantly more weight than those treated with apyrase. Apyrase-treated mice exhibited less colonic goblet cell depletion and apoptotic cells, as well as lower fecal ATP and Stx2, compared to untreated mice. Apyrase also decreased platelet aggregation induced by co-incubation of human platelet-rich-plasma with Stx2 andiE. coli/iO157 lipopolysaccharide in the presence of collagen. Thus, apyrase had multiple protective effects, reducing RecA levels,istx2/iand toxin release from EHEC, reducing fecal Stx2 and protecting mouse intestinal cells, as well as decreasing platelet activation, and could thereby delay the development of disease.

Extracellular vesicles can mediate cell-to-cell communication, or relieve the parent cell of harmful substances, in order to maintain cellular integrity. The content of extracellular vesicles includes miRNAs, mRNAs, growth factors, complement factors, cytokines, chemokines and receptors. These may contribute to inflammatory and infectious diseases by the exposure or transfer of potent effectors that induce vascular inflammation by leukocyte recruitment and thrombosis. Furthermore, vesicles release cytokines and induce their release from cells. Extracellular vesicles possess immune modulatory and anti-microbial properties, and induce receptor signaling in the recipient cell, not least by the transfer of pro-inflammatory receptors. Additionally, the vesicles may carry virulence factors systemically. Extracellular vesicles in blood and urine can contribute to the development of kidney diseases or exhibit protective effects. In this review we will describe the role of EVs in inflammation, thrombosis, immune modulation, angiogenesis, oxidative stress, renal tubular regeneration and infection. Furthermore, we will delineate their contribution to renal ischemia/reperfusion, vasculitis, glomerulonephritis, lupus nephritis, thrombotic microangiopathies, IgA nephropathy, acute kidney injury, urinary tract infections and renal transplantation. Due to their content of miRNAs and growth factors, or when loaded with nephroprotective modulators, extracellular vesicles have the potential to be used as therapeutics for renal regeneration.

Background: The management of malignant bone tumors in children has come a long way in the past few decades. The transition from amputation to limb salvage has been made possible due to the rapid development in the diagnosis and the oncological management of these malignant tumors. However, there exist significant reservations regarding endoprosthetic reconstruction in children. Material and methods: A mini-review was conducted of articles detailing the use of prosthetic reconstruction following tumor resection in children. The data regarding complications and functional outcomes following surgery were collected and presented. Results: The studies reviewed reported a 5-year survival rate between 60 – 70 %. Uniform across the studies was the need for multiple surgeries when endoprosthesis was used for limb reconstruction, ranging between 2.8 – 3.5 surgeries. The most common complication noted across the studies was related to soft tissue problems such as joint instability followed by structural failure of the prosthesis. Infections were noted with a frequency of 10 – 15 %. Studies showed successful management of limb length discrepancy with expandible prosthesis. Musculoskeletal Tumor Society (MSTS) score used to evaluate the functional outcome showed satisfactory outcomes. Conclusion: Limb salvage surgery, with recent advances in technique and prosthesis design, is an attractive option in children with extremity malignant bone tumors. In recent time, endoprosthetic reconstruction of extremities have yielded good functional results and are well accepted by the child and the parents. The purpose of this mini-review is to shed some light on the use of endoprosthetic reconstruction in children following tumor resection with its potential benefits and drawbacks.

Shiga toxin-producing

The intertrochanteric fractures constitute 34% of all hip fractures1. 50% are unstable patterns. DHS and PFN are the two main options for treatment. A prospective randomized control study including 40 patients was carried out. The average blood loss, operating time and complications were significantly higher in the DHS group. PFN provides better fixation for unstable intertrochanteric fractures, if proper preoperative planning, good reduction and surgical technique are followed.

Shiga toxin (Stx) is the main virulence factor of enterohemorrhagic Escherichia coli (EHEC), that cause gastrointestinal infection leading to hemolytic uremic syndrome. The aim of this study was to investigate if Stx signals via ATP and if blockade of purinergic receptors could be protective. Stx induced ATP release from HeLa cells and in a mouse model. Toxin induced rapid calcium influx into HeLa cells, as well as platelets, and a P2X1 receptor antagonist, NF449, abolished this effect. Likewise, the P2X antagonist suramin blocked calcium influx in Hela cells. NF449 did not affect toxin intracellular retrograde transport, however, cells pre-treated with NF449 exhibited significantly higher viability after exposure to Stx for 24 hours, compared to untreated cells. NF449 protected HeLa cells from protein synthesis inhibition and from Stx-induced apoptosis, assayed by caspase 3/7 activity. The latter effect was confirmed by P2X1 receptor silencing. Stx induced the release of toxin-positive HeLa cell- and platelet-derived microvesicles, detected by flow cytometry, an effect significantly reduced by NF449 or suramin. Suramin decreased microvesicle levels in mice injected with Stx or inoculated with Stx-producing EHEC. Taken together, we describe a novel mechanism of Stx-mediated cellular injury associated with ATP signaling and inhibited by P2X receptor blockade.

Aim: To study the functional outcomes of internal fixation in complex tibial plateau fractures. Materials and Methods: 51 patients presenting with complex tibial plateau fractures were treated between January,2013 to January,2016 with various modes of internal fixation depending on the fracture type. Subsequently the patients were followed up at 2,6,12,18 and 24 weeks and then at intervals of three months. Early mobilization was encouraged, and weight bearing was allowed on the basis of callus formation. The functional results were evaluated using the criteria of The Knee Society Clinical Rating System. Results: 18 patients of Schatzker type VI fractures were treated, out of which 9 were treated using only lateral plates, 7 were treated using lateral plates and additional cancellous screws, and 2 were treated using bicondylar plating. 15 patients of Schatzker type V were treated, out of which 10 were treated using lateral lock plates and cancellous screw medially, 4 were treated using only lateral lock plates and 1 was treated with bicondylar plating. Remaining 18 patients of Schatzker type II,III,IV were treated using either only screws or lateral lock plates, buttress plates and screws with or without bone graft. The mean follow up was 1 year (range 10 months to 34 months). All patients were followed up, and their functional outcome was recorded. Conclusions: Good results were obtained with internal fixation. There was good range of motion at the knee joint and excellent functional results.

The objective of this study was to report the clinical phenotype and genetic analysis of two Indian families with Escobar syndrome (ES). The diagnosis of ES in both families was made on the basis of published clinical features. Blood samples were collected from members of both families and used in genomic DNA isolation. The entire coding regions and intron-exon junctions of the ES gene CHRNG (cholinergic receptor, nicotinic, gamma), and two other related genes, CHRND and CHRNA1, were amplified and sequenced to search for mutations in both families. Both families show a typical form of ES. Sequencing of the entire coding regions including the intron-exon junctions of the three genes did not yield any mutations in these families. In conclusion, it is possible that the mutations in these genes are located in the promoter or deep intronic regions that we failed to identify or the ES in these families is caused by mutations in a different gene. The lack of mutations in CHRNG has also been reported in several families, suggesting the possibility of at least one more gene for this syndrome.

Anencephaly (APH) is characterized by the absence of brain tissues and cranium. During primary neurulation stage of the embryo, the rostral part of the neural pore fails to close, leading to APH. APH shows a heterogeneous etiology, ranging from environmental to genetic causes. The autosomal recessive inheritance of APH has been reported in several populations. In this study, we employed whole-exome sequencing and identified a homozygous missense mutation c. 1522C > A (p. Pro508Thr) in the TRIM36 gene as the cause of autosomal recessive APH in an Indian family. The TRIM36 gene is expressed in the developing brain, suggesting a role in neurogenesis. In silico analysis showed that proline at codon position 508 is highly conserved in 26 vertebrate species, and the mutation is predicted to affect the conformation of the B30.2/SPRY domain of TRIM36. Both in vitro and in vivo results showed that the mutation renders the TRIM36 protein less stable. TRIM36 is known to associate with microtubules. Transient expression of the mutant TRIM36 in HeLa and LN229 cells resulted in microtubule disruption, disorganized spindles, loosely arranged chromosomes, multiple spindles, abnormal cytokinesis, reduced cell proliferation and increased apoptosis as compared with cells transfected with its wild-type counterpart. The siRNA knock down of TRIM36 in HeLa and LN229 cells also led to reduced cell proliferation and increased apoptosis. We suggest that microtubule disruption and disorganized spindles mediated by mutant TRIM36 affect neural cell proliferation during neural tube formation, leading to APH.