Better Short-term Outcomes after Total Hip Arthroplasty Compared to Hemiarthroplasty in Active Older Patients with Displaced Intracapsular Femoral Neck Fracture.

BACKGROUND: Hip fractures are a public health problem that disproportionately affects the elderly. Displaced femoral neck fractures were treated historically with hemiarthroplasty, but the use of total hip arthroplasty (THA) is increasing showing superior long-term results. OBJECTIVES: To assess whether THA has superior short-term results compared to bipolar hemiarthroplasty for displaced femoral neck fractures. METHODS: Two groups of active older patients underwent either cementless bipolar hemiarthroplasty or THA for displaced femoral neck fracture. All patients were operated on using the direct lateral approach to the hip joint. Patients were assessed using the Harris Hip Score at hospital discharge and at 6 weeks follow-up. RESULTS: We included 40 patients ages 65-85 years; 18 underwent bipolar hemiarthroplasty and 22 THA. The number of women in each group was similar, as was mean age: 73.1 ± 4.2 years in the hemiarthroplasty group and 71.0 ± 3.7 in THA. Harris Hip Score on hospital discharge was similar in both groups. Walking ability at discharge was better in the THA cohort and they were discharged sooner: 5.2 ± 1.3 vs. 6.4 ± 1.7 days following hemiarthroplasty (P = 0.021). At 6 weeks follow-up, the mean Harris Hip Score was higher in the THA group (78.6 ± 11 vs. 61.5 ± 17 for hemiarthroplasty, P < 0.001). Patients in the THA group walked longer distances, needed less support while walking, and reported less pain. CONCLUSIONS: Better short-term results at hospital discharge and at 6 weeks follow-up after THA contributed to earlier patient independence and shorter hospital stays.

Reversal of dual epigenetic repression of non-canonical Wnt-5a normalises diabetic corneal epithelial wound healing and stem cells.

AIMS/HYPOTHESIS: Diabetes is associated with epigenetic modifications including DNA methylation and miRNA changes. Diabetic complications in the cornea can cause persistent epithelial defects and impaired wound healing due to limbal epithelial stem cell (LESC) dysfunction. In this study, we aimed to uncover epigenetic alterations in diabetic vs non-diabetic human limbal epithelial cells (LEC) enriched in LESC and identify new diabetic markers that can be targeted for therapy to normalise corneal epithelial wound healing and stem cell expression. METHODS: Human LEC were isolated, or organ-cultured corneas were obtained, from autopsy eyes from non-diabetic (59.87±20.89 years) and diabetic (71.93±9.29 years) donors. The groups were not statistically different in age. DNA was extracted from LEC for methylation analysis using Illumina Infinium 850K MethylationEPIC BeadChip and protein was extracted for Wnt phospho array analysis. Wound healing was studied using a scratch assay in LEC or 1-heptanol wounds in organ-cultured corneas. Organ-cultured corneas and LEC were transfected with WNT5A siRNA, miR-203a mimic or miR-203a inhibitor or were treated with recombinant Wnt-5a (200 ng/ml), DNA methylation inhibitor zebularine (1-20 µmol/l) or biodegradable nanobioconjugates (NBCs) based on polymalic acid scaffold containing antisense oligonucleotide (AON) to miR-203a or a control scrambled AON (15-20 µmol/l). RESULTS: There was significant differential DNA methylation between diabetic and non-diabetic LEC. WNT5A promoter was hypermethylated in diabetic LEC accompanied with markedly decreased Wnt-5a protein. Treatment of diabetic LEC and organ-cultured corneas with exogenous Wnt-5a accelerated wound healing by 1.4-fold (p<0.05) and 37% (p<0.05), respectively, and increased LESC and diabetic marker expression. Wnt-5a treatment in diabetic LEC increased the phosphorylation of members of the Ca2+-dependent non-canonical pathway (phospholipase Cγ1 and protein kinase Cß; by 1.15-fold [p<0.05] and 1.36-fold [p<0.05], respectively). In diabetic LEC, zebularine treatment increased the levels of Wnt-5a by 1.37-fold (p<0.01)and stimulated wound healing in a dose-dependent manner with a 1.6-fold (p<0.01) increase by 24 h. Moreover, zebularine also improved wound healing by 30% (p<0.01) in diabetic organ-cultured corneas and increased LESC and diabetic marker expression. Transfection of these cells with WNT5A siRNA abrogated wound healing stimulation by zebularine, suggesting that its effect was primarily due to inhibition of WNT5A hypermethylation. Treatment of diabetic LEC and organ-cultured corneas with NBC enhanced wound healing by 1.4-fold (p<0.01) and 23.3% (p<0.05), respectively, with increased expression of LESC and diabetic markers. CONCLUSIONS/INTERPRETATION: We provide the first account of epigenetic changes in diabetic corneas including dual inhibition of WNT5A by DNA methylation and miRNA action. Overall, Wnt-5a is a new corneal epithelial wound healing stimulator that can be targeted to improve wound healing and stem cells in the diabetic cornea. DATA AVAILABILITY: The DNA methylation dataset is available from the public GEO repository under accession no. GSE229328 ( https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE229328 ).

A modified minimally invasive osteotomy for hallux valgus enables reduction of malpositioned sesamoid bones.

BACKGROUND: The current minimally invasive distal metatarsal osteotomy for hallux valgus (HV) is V-shaped, which prevents the correction of the rotational metatarsal head deformity and reduction of the sesamoid bones. We sought to determine the optimal method for sesamoid bone reduction during HV surgery. METHODS: We reviewed the medical records of 53 patients who underwent HV surgery between 2017 and 2019 using one of three techniques: open chevron osteotomy (n = 19), minimally invasive V-shaped osteotomy (n = 18), and a modified straight minimally invasive osteotomy (n = 16). The sesamoid position was graded using the Hardy and Clapham method on weight-bearing radiographs. RESULTS: When compared to open chevron and V-shaped osteotomies, the modified osteotomy resulted in significantly lower postoperative sesamoid position scores (3.74 ± 1.48, 4.61 ± 1.09, and 1.44 ± 0.81, respectively, P < 0.001). Furthermore, the mean change in postoperative sesamoid position score was greater (P < 0.001). CONCLUSION: The modified minimally invasive osteotomy was superior to the other two techniques in correcting HV deformity in all planes, including sesamoid reduction.

Results of corneal collagen cross-linking in patients with corneal ectasia after laser refractive surgery-A prospective study.

PURPOSE: To evaluate the safety and efficacy of epithelium-off (epi­off) corneal cross-linking (CXL) in patients with post-LASIK corneal ectasia (PLE) SETTING: Private clinical practice DESIGN: Prospective clinical trial METHODS: 82 eyes of adult patients post-LASIK, ages 21-67, with a topography pattern consistent with corneal ectasia, corrected distance visual acuity (CDVA) worse than 20/20, and minimum corneal pachymetry > 400 µm underwent epi­off CXL. Exclusion criteria were patients with corneas that were thinner than 400 µm or demonstrated central corneal scarring, history of herpetic eye disease, pregnancy or nursing. Follow up examinations of spherical equivalent, uncorrected distance visual acuity (UDVA), CDVA, steep keratometry (KSteep) and minimum pachymetry occurred on different but highly overlapping subsets of the operated eyes yearly until 5 years post-CXL. RESULTS: Over the 5 years of follow up, spherical equivalent did not significantly change while UCVA and CDVA stabilized or improved to a non-significant degree. KSteep and minimum pachymetry continued to be decreased to a statistically significant degree (p < 0.05 at 5 years). CONCLUSIONS: CXL in PLE patients is safe and efficacious: it halts progression of PLE and may improve visual function. KSteep and minimum pachymetry decrease post-CXL. Patients with PLE should be encouraged to stop progression of the disease by undergoing epi­off CXL once progression is established.

Ribosomal proteins as distinct "passengers" of microvesicles: new semantics in myeloma and mesenchymal stem cells' communication.

Aberrant mesenchymal stem cells (MSCs) in multiple myeloma (MM) bone marrows (BM) promote disease progression and drug resistance. Here, we assayed the protein cargo transported from MM-MSCs to MM cells via microvesicles (MVs) with focus on ribosomal proteins (RPs) and assessment of their influence on translation initiation and design of MM phenotype. Proteomics analysis (mass spectrometry) demonstrated increased levels and repertoire of RPs in MM-MSCs MVs compared to normal donors (ND) counterparts (n = 3-8; P = 9.96E - 08). We limited the RPs load in MM-MSCs MVs (starvation, RSK and XPO1 inhibitions), reapplied the modified MVs to MM cell lines (U266, MM1S), and demonstrated that the RPs are essential to the proliferative effect of MM-MSCs MVs on MM cells (n = 3; P < 0.05). We also observed that inhibition with KPT-185 (XPO1 inhibitor) displayed the most extensive effect on RPs delivery into the MVs (↓80%; P = 3.12E - 05). Using flow cytometry we assessed the expression of select RPs (n = 10) in BM-MSCs cell populations (ND and MM; n ≥ 6 each). This demonstrated a heterogeneous expression of RPs in MM-MSCs with distinct subgroups, a phenomenon absent from ND-MSCs samples. These findings bring to light a new mechanism in which the tumor microenvironment participates in cancer promotion. MVs-mediated horizontal transfer of RPs between niche MSCs and myeloma cells is a systemic way to bestow pro-cancer advantages. This capacity also differentiates normal MSCs from the MM-modified MSCs and may mark their reprogramming. Future studies will be aimed at assessing the clinical and therapeutic potential of the increased RPs levels in MM-MSCs MVs.

Results of corneal crosslinking in adolescents with progressive keratoconus: prospective study.

PURPOSE: To evaluate the safety and efficacy of epithelium-off (epi-off) corneal crosslinking (CXL) in adolescents with progressive keratoconus (KC). SETTING: Private clinical practice. DESIGN: Nonrandomized prospective clinical trial. METHODS: 230 adolescent patients aged 10 to 19 years with progressive KC (increasing maximum keratometry [Kmax] or astigmatism of 1.00 diopter or greater associated with decreased corrected distance visual acuity [CDVA]) underwent CXL. Exclusion criteria were age at time of CXL younger than 10 years or older than 19 years, corneas that were thinner than 400 µm or demonstrated central corneal scarring, history of herpetic eye disease, or pregnancy or nursing. Follow-up examinations of uncorrected distance visual acuity (UDVA), CDVA, Kmax, and minimum pachymetry occurred on 130 eyes at 1 year, 77 eyes at 2 years, and 55 eyes at 3 years post-CXL. RESULTS: In this study, 230 eyes of adolescent patients were evaluated. UDVA significantly improved from preoperatively to 1 year, 2 years, and 3 years post-CXL. CDVA values significantly improved from preoperatively to 1 year, 2 years, and 3 years post-CXL. Kmax values significantly reduced (improved) from preoperatively to 1 year and 3 years post-CXL and reduced (improved) (P = .22) from preoperatively to 2 years post-CXL. Minimum pachymetry decreased significantly from preoperatively to 1 year, 2 years, and 3 years post-CXL. CONCLUSIONS: CXL in patients aged 10 to 19 years was safe and efficacious, halted progression of KC and could improve UCVA, CDVA, and Kmax. Minimum pachymetry decreased and stabilized post-CXL. Ophthalmologists should encourage adolescent patients with KC to obtain prompt evaluation and possible CXL to halt progression of the disease.

Genetics vs chronic corneal mechanical trauma in the etiology of keratoconus.

Both genetic and environmental factors have been considered to play a role in the etiology keratoconus. Eye rubbing, and more recently eye compression due to sleeping position, have been identified to be highly related to the condition, and are present in a high percentage of patients. Today, the predominant model is that these factors can provide the "second hit" necessary to generate the condition in a genetically susceptible individual. In addition, the extremely high prevalence in Arab populations, where endogamy could play a role, the high concordance rate in monozygotic twins, and the presence of family history of the condition between 5 and 23% of cases, support a genetic influence. Segregation analysis studies suggest that keratoconus is a complex non-Mendelian disease. Results from linkage analysis, next generation sequencing studies and genome-wide association studies also have suggested that genetic factors are involved in the condition. Recently, it has been proposed that mechanical trauma (i.e. eye rubbing or eye compression at night), is a sine quanon condition for the onset of keratoconus, and quite possibly its only cause. There are various arguments for and against this hypothesis. Indeed, it is possible, as initially suggested around 55 years ago, that the term "keratoconus" include diverse phenotypically similar conditions, which are actually of different etiology.

Update on the genetics of keratoconus.

In the past few years we have seen a great acceleration of discoveries in the field of keratoconus including new treatments, diagnostic tools, genomic and molecular determinants of disease risk. Recent genome-wide association studies (GWAS) of keratoconus cases and population wide studies of variation in central corneal thickness and in corneal biomechanical properties confirmed already identified genes and found many new susceptibility variants and biological pathways. Recent findings in genetic determinants of familial keratoconus revealed functionally important variants and established first mouse model of keratoconus. Latest transcriptomic and expression studies started assessing novel non-coding RNA targets in addition to identifying tissue specific effects of coding genes. First genomic insights into better prediction of treatment outcomes are bringing the advent of genomic medicine into keratoconus clinical practice.

Novel nanopolymer RNA therapeutics normalize human diabetic corneal wound healing and epithelial stem cells.

Human diabetic corneas develop delayed wound healing, epithelial stem cell dysfunction, recurrent erosions, and keratitis. Adenoviral gene therapy modulating c-Met, cathepsin F and MMP-10 normalized wound healing and epithelial stem cells in organ-cultured diabetic corneas but showed toxicity in stem cell-enriched cultured limbal epithelial cells (LECs). For a safer treatment, we engineered a novel nanobiopolymer (NBC) that carried antisense oligonucleotide (AON) RNA therapeutics suppressing cathepsin F or MMP-10, and miR-409-3p that inhibits c-Met. NBC was internalized by LECs through transferrin receptor (TfR)-mediated endocytosis, inhibited cathepsin F or MMP-10 and upregulated c-Met. Non-toxic NBC modulating c-Met and cathepsin F accelerated wound healing in diabetic LECs and organ-cultured corneas vs. control NBC. NBC treatment normalized levels of stem cell markers (keratins 15 and 17, ABCG2, and ΔNp63), and signaling mediators (p-EGFR, p-Akt and p-p38). Non-toxic nano RNA therapeutics thus present a safe alternative to viral gene therapy for normalizing diabetic corneal cells.

Association of Genetic Variation With Keratoconus.

Importance: Keratoconus is a condition in which the cornea progressively thins and protrudes in a conical shape, severely affecting refraction and vision. It is a major indication for corneal transplant. To discover new genetic loci associated with keratoconus and better understand the causative mechanism of this disease, we performed a genome-wide association study on patients with keratoconus. Objective: To identify genetic susceptibility regions for keratoconus in the human genome. Design, Setting, and Participants: This study was conducted with data from eye clinics in Australia, the United States, and Northern Ireland. The discovery cohort of individuals with keratoconus and control participants from Australia was genotyped using the Illumina HumanCoreExome single-nucleotide polymorphism array. After quality control and data cleaning, genotypes were imputed against the 1000 Genomes Project reference panel (phase III; version 5), and association analyses were completed using PLINK version 1.90. Single-nucleotide polymorphisms with P < 1.00 × 10-6 were assessed for replication in 3 additional cohorts. Control participants were drawn from the cohorts of the Blue Mountains Eye Study and a previous study of glaucoma. Replication cohorts were from a previous keratoconus genome-wide association study data set from the United States, a cohort of affected and control participants from Australia and Northern Ireland, and a case-control cohort from Victoria, Australia. Data were collected from January 2006 to March 2019. Main Outcomes and Measures: Associations between keratoconus and 6 252 612 genetic variants were estimated using logistic regression after adjusting for ancestry using the first 3 principal components. Results: The discovery cohort included 522 affected individuals and 655 control participants, while the replication cohorts included 818 affected individuals (222 from the United States, 331 from Australia and Northern Ireland, and 265 from Victoria, Australia) and 3858 control participants (2927 from the United States, 229 from Australia and Northern Ireland, and 702 from Victoria, Australia). Two novel loci reached genome-wide significance (defined as P < 5.00 × 10-8), with a P value of 7.46 × 10-9 at rs61876744 in patatin-like phospholipase domain-containing 2 gene (PNPLA2) on chromosome 11 and a P value of 6.35 × 10-12 at rs138380, 2.2 kb upstream of casein kinase I isoform epsilon gene (CSNK1E) on chromosome 22. One additional locus was identified with a P value less than 1.00 × 10-6 in mastermind-like transcriptional coactivator 2 (MAML2) on chromosome 11 (P = 3.91 × 10-7). The novel locus in PNPLA2 reached genome-wide significance in an analysis of all 4 cohorts (P = 2.45 × 10-8). Conclusions and Relevance: In this relatively large keratoconus genome-wide association study, we identified a genome-wide significant locus for keratoconus in the region of PNPLA2 on chromosome 11.

Sample Tracking Using Unique Sequence Controls.

Sample tracking and identity are essential when processing multiple samples in parallel. Sequencing applications often involve high sample numbers, and the data are frequently used in a clinical setting. As such, a simple and accurate intrinsic sample tracking process through a sequencing pipeline is essential. Various solutions have been implemented to verify sample identity, including variant detection at the start and end of the pipeline using arrays or genotyping, bioinformatic comparisons, and optical barcoding of samples. None of these approaches are optimal. To establish a more effective approach using genetic barcoding, we developed a panel of unique DNA sequences cloned into a common vector. A unique DNA sequence is added to the sample when it is first received and can be detected by PCR and/or sequencing at any stage of the process. The control sequences are approximately 200 bases long with low identity to any sequence in the National Center for Biotechnology Information nonredundant database (<30 bases) and contain no long homopolymer (>7) stretches. When a spiked next-generation sequencing library is sequenced, sequence reads derived from this control sequence are generated along with the standard sequencing run and are used to confirm sample identity and determine cross-contamination levels. This approach is used in our targeted clinical diagnostic whole-genome and RNA-sequencing pipelines and is an inexpensive, flexible, and platform-agnostic solution.

PPIP5K2 and PCSK1 are Candidate Genetic Contributors to Familial Keratoconus.

Keratoconus (KC) is the most common corneal ectatic disorder affecting >300,000 people in the US. KC normally has its onset in adolescence, progressively worsening through the third to fourth decades of life. KC patients report significant impaired vision-related quality of life. Genetic factors play an important role in KC pathogenesis. To identify novel genes in familial KC patients, we performed whole exome and genome sequencing in a four-generation family. We identified potential variants in the PPIP5K2 and PCSK1 genes. Using in vitro cellular model and in vivo gene-trap mouse model, we found critical evidence to support the role of PPIP5K2 in normal corneal function and KC pathogenesis. The gene-trap mouse showed irregular corneal surfaces and pathological corneal thinning resembling KC. For the first time, we have integrated corneal tomography and pachymetry mapping into characterization of mouse corneal phenotypes which could be widely implemented in basic and translational research for KC diagnosis and therapy in the future.

Corneal Perforation After Corneal Cross-Linking in Keratoconus Associated With Potentially Pathogenic ZNF469 Mutations.

PURPOSE: To report a case of bilateral and repetitive corneal perforations after corneal cross-linking (CXL) for keratoconus in a woman harboring potentially pathogenic variants in the ZNF469 gene and to characterize the keratoconus phenotype in this woman and her daughter who shared the same ZNF469 mutations. METHODS: Clinical characterization of the proband and her daughter followed by sequencing of the genes associated with brittle cornea syndrome, ZNF469 and PRDM5, in both individuals. RESULTS: An Ashkenazi Jewish woman in her sixth decade presented with diffuse corneal thinning and progressive steepening consistent with keratoconus. After CXL, epithelium-off in the first eye and epithelium-on in the second, she developed spontaneous corneal perforations in each eye. Her daughter in her fourth decade demonstrated a similar pattern of diffuse corneal thinning and progressive corneal steepening but did not undergo CXL and did not develop corneal perforation. Screening of the ZNF469 and PRDM5 genes revealed 3 missense ZNF469 variants (c.2035G>A, c.10244G>C, and c.11119A>G) in cis arrangement on 1 allele of ZNF469 in both proband and her daughter. Although the 3 variants share low (<0.01) global minor allele frequencies, each has significantly higher minor allele frequencies (0.01-0.03) in the Ashkenazi Jewish population, leading to uncertainty regarding a pathogenic role for the identified variants. CONCLUSIONS: CXL may be associated with the development of corneal perforation in particular at-risk individuals with keratoconus. Identifying clinical and genetic risk factors, including screening of ZNF469 and PRDM5, may be useful in the prevention of significant complications after CXL.

Orthopedic-Metabolic Collaborative Management for Osteoporotic Hip Fracture.

OBJECTIVE: Osteoporotic hip fractures are associated with increased morbidity, mortality, and secondary fractures. Although osteoporosis treatment can reduce future fracture risk, patients often do not receive it. We report results of a coordinator-less fracture liaison service in Israel addressing hip fracture patients. The primary endpoint was attending the Metabolic Clinic. Secondary endpoints included vitamin D measurement, calcium and vitamin D recommendations, initiation of osteoporosis treatment, and mortality 1-year post-fracture. METHODS: This prospective study included 219 hip fracture patients who were compared with historical controls. Data on hospitalized patients were collected before and after implementation of a structured protocol for hip fracture patients, led by a multidisciplinary team, without a coordinator. RESULTS: The study included 219 and 218 patients ≥60 years old who were operated on in 2013 and 2012, respectively. Metabolic Clinic visits increased from 6.4 to 40.2% after the intervention ( P<.001). Among 14 patients who attended the Clinic in 2012, 85.7% began osteoporosis therapy; among 88 who attended in 2013, 45.5% were treated at the first visit. Vitamin D measurements and calcium and vitamin D supplementation increased postintervention (0.5-80.1%, P<.001; 30.8-84.7%, P<.001, respectively). Patients receiving osteoporosis medications had lower mortality rates than untreated patients (4.3% vs. 21.8%). CONCLUSION: An Orthopedic-Metabolic team implemented by existing staff without a coordinator can improve osteoporosis care for hip fracture patients. Yet, gaps remain as only 40% had Metabolic Clinic follow-up postintervention, and of these, only half received specific treatment recommendations. Hospitals are encouraged to adopt secondary fracture prevention protocols and continuously improve them to close the gaps between current management and appropriate metabolic assessment and treatment. ABBREVIATIONS: CHS = Clalit Health Services; CI = confidence interval; FLS = fracture liaison service; HMO = health maintenance organization; OR = odds ratio.

Routine early post-operative X-ray following internal fixation of intertrochanteric femoral fractures is unjustified: a quality improvement study.

BACKGROUND: There is no consensus regarding the proper radiographic protocol following closed or open reduction and internal fixation for intertrochanteric femoral fractures. The objective of this study was to assess the role of early postoperative imaging studies when deciding about weight bear limitations and reoperations. METHODS: A prospective cohort study of 100 patients (26 men and 74 women, at a mean age of 79.8 years) treated by closed or open reduction and internal fixation for AO31A fractures was conducted. According to the AO classification, there were 25 cases of 31A1, 54 cases of 31A2, and 21 cases of 31A3. For every patient, the intraoperative fluoroscopy studies were recorded and post-operative radiograms were taken during the first week. Excluded were patients for whom the early X-rays were clinically indicated. The intraoperative AP and axial fluoroscopy studies were compared with the radiograms taken during the first post-operative week. The investigators compared the decisions regarding weight-bearing limitations and the need for re-operation before and after conducting the radiograms. RESULTS: The early post-operative imaging studies did not change weight-bearing limitations nor did they lead to consecutive surgical treatments. CONCLUSIONS: Unless indicated by physical examination, there is no value to routine post-operative radiograms within the first few days after closed reduction and internal fixation of intertrochanteric femoral fractures with regard to weight-bearing limitations and re-operation decisions. TRIAL REGISTRATION: Identifier: NCT02868125 .

The single-domain response regulator LerC functions as a connector protein in the Legionella pneumophila effectors regulatory network.

The intracellular pathogen Legionella pneumophila translocates more than 300 effector proteins into host cells during infection. The PmrAB two-component system (TCS) has been shown to activate the expression of a large pool of these effector-encoding genes (EEGs) and the LetAS TCS, as part of the LetAS-RsmYZ-CsrA cascade, has been shown to repress the expression of another pool of EEGs. We identified a single-domain response regulator (SDRR), named LerC, which functions as a connector protein between the PmrAB and the LetAS TCSs. The lerC gene is strongly activated by the PmrAB TCS and the LerC protein inhibits the activity of the LetAS TCS. The LerC protein specifically interacts with the HPT (histidine-phosphotransfer) domain of LetS, leading to reduced expression of the small RNAs RsmY and RsmZ, which leads to a reduced expression of the pool of EEGs regulated by the LetAS-RsmYZ-CsrA cascade. In addition, the conserved aspartic acid located in the LerC receiver domain is essential for its phosphorylation and function, suggesting that LerC functions as a phosphate-sink of LetS. Our results demonstrate a new role for SDRRs as connector proteins in regulatory networks, suggesting that members of this widespread group of proteins might function as connector proteins in other bacterial regulatory networks.

Differential Expression of Coding and Long Noncoding RNAs in Keratoconus-Affected Corneas.

Purpose: Keratoconus (KC) is the most common corneal ectasia. We aimed to determine the differential expression of coding and long noncoding RNAs (lncRNAs) in human corneas affected with KC. Methods: From the corneas of 10 KC patients and 8 non-KC healthy controls, 200 ng total RNA was used to prepare sequencing libraries with the SMARTer Stranded RNA-Seq kit after ribosomal RNA depletion, followed by paired-end 50-bp sequencing with Illumina Sequencer. Differential analysis was done using TopHat/Cufflinks with a gene file from Ensembl and a lncRNA file from NONCODE. Pathway analysis was performed using WebGestalt. Using the expression level of differentially expressed coding and noncoding RNAs in each sample, we correlated their expression levels in KC and controls separately and identified significantly different correlations in KC against controls followed by visualization using Cytoscape. Results: Using |fold change| ≥ 2 and a false discovery rate ≤ 0.05, we identified 436 coding RNAs and 584 lncRNAs with differential expression in the KC-affected corneas. Pathway analysis indicated the enrichment of genes involved in extracellular matrix, protein binding, glycosaminoglycan binding, and cell migration. Our correlation analysis identified 296 pairs of significant KC-specific correlations containing 117 coding genes enriched in functions related to cell migration/motility, extracellular space, cytokine response, and cell adhesion. Our study highlighted the potential roles of several genes (CTGF, SFRP1, AQP5, lnc-WNT4-2:1, and lnc-ALDH3A2-2:1) and pathways (TGF-ß, WNT signaling, and PI3K/AKT pathways) in KC pathogenesis. Conclusions: Our RNA-Seq-based differential expression and correlation analyses have identified many potential KC contributing coding and noncoding RNAs.

Corneal Cross-Linking for Pediatric Keratcoconus Review.

PURPOSE: To comprehensively review the available published literature for cross-linking in the pediatric population. METHODS: Review of the literature published in English in PubMed. RESULTS: Two hundred ten publications were considered. One hundred fifteen were considered relevant to this review. CONCLUSIONS: Studies of cross-linking in pediatric patients are sparse, with relatively short follow-up times, and mostly on small groups of patients. Treatment with cross-linking halts progression of keratoconus in the pediatric population, and early treatment seems to be cost-effective compared with later penetrating keratoplasty. Long-term effects and regression rates remain unclear, and further studies are needed in this population.

TSC1 Mutations in Keratoconus Patients With or Without Tuberous Sclerosis.

Purpose: To test candidate genes TSC1 and TSC2 in a family affected by tuberous sclerosis complex (TSC) where proband was also diagnosed with bilateral keratoconus (KC) and to test the hypothesis that defects in the same gene may lead to a nonsyndromic KC. Methods: Next-generation sequencing of TSC1 and TSC2 genes was performed in a proband affected by TSC and KC. Identified mutation was confirmed by Sanger DNA sequencing. Whole exome sequencing (WES) was performed in patients with nonsyndromic KC. Sanger DNA sequencing was used to confirm WES results and to screen additional patients. RT-PCR was used to investigate TSC1 expression in seven normal human corneas and eight corneas from patients with KC. Various in silico tools were employed to model functional consequences of identified mutations. Results: A heterozygous nonsense TSC1 mutation g.132902703C>T (c.2293C>T, p.Gln765Ter) was identified in a patient with TSC and KC. Two heterozygous missense TSC1 variants g.132896322A>T (c.3408A>T, p.Asp1136Glu) and g.132896452G>A (c.3278G>A, p.Arg1093Gln) were identified in three patients with nonsyndromic KC. Two mutations were not present in The Genome Aggregation (GnomAD), The Exome Aggregation (ExAC), and 1000 Genomes (1000G) databases, while the third one was present in GnomAD and 1000G with minor allele frequencies (MAF) of 0.00001 and 0.0002, respectively. We found TSC1 expressed in normal corneas and KC corneas, albeit with various levels. Conclusions: Here for the first time we found TSC1 gene to be involved in bilateral KC and TSC as well as with nonsyndromic KC, supporting the hypothesis that diverse germline mutations of the same gene can cause genetic disorders with overlapping clinical features.

The incidence of life threatening iatrogenic vessel injury following closed or open reduction and internal fixation of intertrochanteric femoral factures.

AIM OF THE STUDY: Bleeding due to a vascular injury is a possible life-threatening complication of intertrochanteric femoral fracture internal fixation. Our goals were to find the current incidence of these events, and to describe the reasons, the presentation, and the treatment options. METHOD: We conducted a retrospective record review of 1,469 patients who were operated upon at our institution due to AO31A femoral fractures from 2011 through 2015 and were treated with closed reduction and internal fixation. RESULTS: Three patients were diagnosed with iatrogenic vascular bleeding, which constitute an incidence of 0.2%. The vascular injuries were detected as deep femoral artery bleeding adjacent to the distal locking screws. The patients were treated with ultrasound guided thrombin injection, endovascular coil embolization or with no endovascular intervention. DISCUSSION: Vascular injuries are caused mainly by perforating a vessel while drilling the distal locking screw holes. A high level of suspicion and immediate imaging work-up are mandatory. CONCLUSIONS: A vascular injury due to internal fixation of a proximal AO31A femoral fracture is a rare complication.