DNAJC13 mutations in Parkinson disease.

A Saskatchewan multi-incident family was clinically characterized with Parkinson disease (PD) and Lewy body pathology. PD segregates as an autosomal-dominant trait, which could not be ascribed to any known mutation. DNA from three affected members was subjected to exome sequencing. Genome alignment, variant annotation and comparative analyses were used to identify shared coding mutations. Sanger sequencing was performed within the extended family and ethnically matched controls. Subsequent genotyping was performed in a multi-ethnic case-control series consisting of 2928 patients and 2676 control subjects from Canada, Norway, Taiwan, Tunisia, and the USA. A novel mutation in receptor-mediated endocytosis 8/RME-8 (DNAJC13 p.Asn855Ser) was found to segregate with disease. Screening of cases and controls identified four additional patients with the mutation, of which two had familial parkinsonism. All carriers shared an ancestral DNAJC13 p.Asn855Ser haplotype and claimed Dutch-German-Russian Mennonite heritage. DNAJC13 regulates the dynamics of clathrin coats on early endosomes. Cellular analysis shows that the mutation confers a toxic gain-of-function and impairs endosomal transport. DNAJC13 immunoreactivity was also noted within Lewy body inclusions. In late-onset disease which is most reminiscent of idiopathic PD subtle deficits in endosomal receptor-sorting/recycling are highlighted by the discovery of pathogenic mutations VPS35, LRRK2 and now DNAJC13. With this latest discovery, and from a neuronal perspective, a temporal and functional ecology is emerging that connects synaptic exo- and endocytosis, vesicular trafficking, endosomal recycling and the endo-lysosomal degradative pathway. Molecular deficits in these processes are genetically linked to the phenotypic spectrum of parkinsonism associated with Lewy body pathology.

Alpha-synuclein p.H50Q, a novel pathogenic mutation for Parkinson's disease.

BACKGROUND: Alpha-synuclein plays a central role in the pathophysiology of Parkinson's disease. Three missense mutations in SNCA, the gene encoding alpha-synuclein, as well as genomic multiplications have been identified as causes for autosomal-dominantly inherited Parkinsonism. METHODS: Here, we describe a novel missense mutation in exon 4 of SNCA encoding a H50Q substitution in a patient with dopa-responsive Parkinson's disease with a family history of parkinsonism and dementia. RESULTS: The variant was not observed in public databases or identified in unrelated subjects. CONCLUSIONS: The substitution's evolutionary conservation and protein modeling provide additional support for pathogenicity as the amino acid perturbs the same amphipathic alpha helical structure as the previously described pathogenic mutations.

Erratum: Correction of missing funding information. A new phantom to evaluate the tissue dissolution ability of endodontic irrigants and activating devices.

[This corrects the article e45 in vol. 45, PMID: 33294410.].

A new phantom to evaluate the tissue dissolution ability of endodontic irrigants and activating devices.

OBJECTIVE: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. MATERIALS AND METHODS: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. RESULTS: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. CONCLUSIONS: Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

1-year outcomes of the Xen45 glaucoma implant.

OBJECTIVES: To describe the 12-month outcomes of the Xen45 glaucoma stent. METHODS: Non-comparative retrospective study of all cases who underwent Xen glaucoma surgery in April 2017 or earlier and completed 12 months of follow-up. The primary outcome measures were intraocular pressure (IOP) reduction and number of glaucoma medications at 12 months postoperatively. The secondary outcome measures were surgical complications and the success rate of surgery at 1 year. Success rate was defined according to the multiple IOP thresholds of 15 mmHg, 18 mmHg, and 21 mmHg with all requiring a drop of 20% and no additional glaucoma surgery. Revision or needling of the Xen conjunctival bleb was not considered to constitute a surgical failure. RESULTS: Sixty-eight eyes were included in the study. Mean IOP dropped from 22.1 mmHg preoperatively to 14.8 mmHg at 12 months, a 33% drop (p < 0.0001). Mean number of glaucoma medications reduced from 2.9 preoperatively to 1.1 at 12 months (p < 0.0001). In total, 54.4% of cases were back on glaucoma medications by 12 months. Success rate varied from 32.4% when defined as IOP ≤ 15 mmHg and ≥ 6 mmHg and ≥ 20% reduction without medications to 70.6% when defined as IOP ≤ 21 mmHg and ≥ 6 mmHg and ≥ 20% reduction with or without medications. Thirty cases (44.1%) required bleb needling or surgical revision. CONCLUSIONS: The Xen45 is effective at reducing IOP and glaucoma medication use at 12 months postoperatively. Patients considering this procedure should be warned that by 12 months postoperatively there is a significant chance of requiring postoperative bleb intervention and glaucoma drops.

Bone Quality and Quantity Alterations After Socket Augmentation with rhPDGF-BB or BMPs: A Systematic Review.

PURPOSE: The aim of this study was to systematically analyze the effect of growth factors, particularly recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and bone morphogenetic proteins (BMPs), on volumetric and histomorphometric changes after socket augmentation in comparison with the natural healing sockets. MATERIALS AND METHODS: An electronic search of four databases (1965 to February 2017) and a hand search of peer-reviewed journals for relevant articles were performed. Human clinical trials that reported quantitative and qualitative outcomes of soft and hard tissues in socket augmented sites with the use of rhPDGF-BB or BMPs, with a minimum five samples per group, were included. RESULTS: Eight studies, including six randomized controlled trials and two case series, were selected. Five of them used BMPs, and three used rhPDGF-BB. Regarding linear bone width change, the weighted mean difference (WMD) between the sites with and without the use of BMPs was 1.66 mm (95% confidence interval = 0.29 to 3.02 mm, P = .02), favoring the BMP group. In terms of histomorphometric outcome, the WMD of the percentage of vital bone between the sites with the use of rhPDGF-BB and with grafting materials alone was 2.16% (95% confidence interval = -4.61% to 8.93%, P = .53). CONCLUSION: This systematic review revealed that the use of BMPs in socket augmentation yields better ridge width in comparison with a natural healing socket. However, more studies are needed to warrant the effectiveness when using rhPDGF-BB in socket augmentation procedures.

Gonioscopically Guided Nonpenetrating Cyclodialysis Cleft Repair: A Novel Surgical Technique.

AIM: We present a novel surgical technique for repair of persistent and symptomatic cyclodialysis clefts refractory to conservative or minimally invasive treatment. BACKGROUND: Numerous surgical techniques have been described to close cyclodialysis clefts. The current standard approach involves intraocular repair of cyclodialysis clefts underneath a full-thickness scleral flap. TECHNIQUE: Our technique employs intraoperative use of a direct gonioscope to guide a nonpenetrating surgical repair. Subsequently, a significantly less invasive, nonpenetrating technique utilizing a partial-thickness scleral flap can be performed that reduces potential risks associated with intraocular surgery. The direct gonioscope is also used for confirmation of adequate surgical closure of the cyclodialysis cleft prior to completion of surgery. This technique has been successfully carried out to repair traumatic chronic cyclodialysis clefts associated with hypotony in two patients. There were no significant adverse events as a result of using this technique. CONCLUSION: The novel technique described increases the likelihood of successful and permanent repair of cyclodialysis clefts with resolution of symptoms associated with hypotony, through direct intraoperative visualization of the cleft. CLINICAL SIGNIFICANCE: Gonioscopically guided nonpenetrating cyclodialysis cleft repair offers significant benefits over previously described techniques. Advantages of our technique include gonioscopic cleft visualization, enabling accurate localization of the area requiring repair, and subsequent confirmation of adequate closure of the cleft. Using a partial-thickness scleral flap is also less invasive and reduces risks associated with treatment of this potentially challenging complication of ocular trauma. HOW TO CITE THIS ARTICLE: Rodrigues IAS, Shah B, Goyal S, Lim S. Gonioscopically Guided Nonpenetrating Cyclodialysis Cleft Repair: A Novel Surgical Technique. J Curr Glaucoma Pract 2017;11(1):31-34.

Recent advancements in regenerative dentistry: A review.

Although human mouth benefits from remarkable mechanical properties, it is very susceptible to traumatic damages, exposure to microbial attacks, and congenital maladies. Since the human dentition plays a crucial role in mastication, phonation and esthetics, finding promising and more efficient strategies to reestablish its functionality in the event of disruption has been important. Dating back to antiquity, conventional dentistry has been offering evacuation, restoration, and replacement of the diseased dental tissue. However, due to the limited ability and short lifespan of traditional restorative solutions, scientists have taken advantage of current advancements in medicine to create better solutions for the oral health field and have coined it "regenerative dentistry." This new field takes advantage of the recent innovations in stem cell research, cellular and molecular biology, tissue engineering, and materials science etc. In this review, the recently known resources and approaches used for regeneration of dental and oral tissues were evaluated using the databases of Scopus and Web of Science. Scientists have used a wide range of biomaterials and scaffolds (artificial and natural), genes (with viral and non-viral vectors), stem cells (isolated from deciduous teeth, dental pulp, periodontal ligament, adipose tissue, salivary glands, and dental follicle) and growth factors (used for stimulating cell differentiation) in order to apply tissue engineering approaches to dentistry. Although they have been successful in preclinical and clinical partial regeneration of dental tissues, whole-tooth engineering still seems to be far-fetched, unless certain shortcomings are addressed.

Donor pericardium graft repair of traumatic globe rupture at previous trabeculectomy site.

A 65-year-old man with a history of bilateral trabeculectomy augmented with mitomycin C underwent surgery for a scleral rupture following trauma. The site of the rupture was a posterior extension of the scleral flap. Attempted closure of a ragged scleral wound was not possible without excessive distortion and induced astigmatism. Persistent hypotony due to over drainage was treated by patching the site with a donor pericardium graft, secured with 10-0 nylon sutures. Although the trabeculectomy became nonfunctional and further glaucoma surgery was eventually required, a good visual outcome was achieved due to early repair following trauma.

Isolated extraocular muscle abscess presenting 40 years after squint surgery.

A 57-year-old man presented with an abscess localised to the lateral rectus region. He was treated as a case of orbital cellulitis because of the presence of soft tissue swelling with a localised abscess discharging through the conjunctiva with associated reduction of visual acuity and restriction of ocular movements laterally. No specific risk factors were identified but an ultrasound scan picked up a hyperechoic signal suggestive of a foreign body within the abscess. Surgical exploration did not identify a foreign body but fibrotic changes between the globe and the lateral rectus muscle were found which was suggestive of previous squint surgery. This was confirmed by the patient later on specific questioning. Periorbital infection is a rare occurrence after squint surgery and reported cases are mainly within a week after surgery. Orbital abscess probably related to an old suture granuloma 40 years after surgery has not been documented before.

Developing an iMALDI method.

The iMALDI (immuno-MALDI) technique involves the affinity capture of target peptides from an enzymatic digest of a sample, followed by the direct analysis of the affinity beads while on a MALDI target. For determination of peptide concentration (and, by inference, protein concentration), stable-isotope-labeled standard peptides (SIS peptides) can be added to the digest and will be captured along with the native peptides. This technique can provide the highest possible specificity by determining two molecular characteristics of the epitope-containing peptides: (1) the molecular weight, typically measured to within 100 ppm or better by MALDI-MS, and (2) the amino acid sequence, by performing MALDI-MS/MS. This technique has been shown to be capable of detecting low-attomole levels of target peptides in environmental samples and in digests of human plasma. This chapter provides a detailed description of how to perform iMALDI analyses, starting with the selection of the target peptides. Examples are shown of the application of iMALDI to the detection of an organism that is a possible bioterrorism threat, and to the detection of two isoforms of human EGFR.

STX6 rs1411478 is not associated with increased risk of Parkinson's disease.

A variant in Syntaxin 6 (a soluble N-ethylmaleimide-sensitive factor attachment protein receptor STX6) (rs1411478) has been shown to be associated with progressive supranuclear palsy (PSP). Although Parkinson's disease (PD) and PSP are distinct neurodegenerative diseases, they share some clinical and genetic features. In this study, we evaluated STX6 genetic variability in PD susceptibility in ethnically matched case-control series from Canada, Norway, Taiwan and Tunisia and we evaluated the presence of pathogenic mutations within families. No pathogenic mutations were found in STX6. Similarly, statistical analysis of rs1411478 failed to identify differences in genotype or allelic frequencies between cases and controls. Our results do not support a role for STX6 in PD.

Emerging mass spectrometry-based technologies for analyses of chromatin changes: analysis of histones and histone modifications.

Mass spectrometry (MS) is rapidly becoming an indispensable tool for the analysis of posttranslational modifications (PTMs) of proteins, and particularly histone PTMs that regulate physiological processes. The more traditional bottom-up approach of searching for modifications on peptides rather than intact proteins (top-down) has proven useful for finding phosphorylation, acetylation, and ubiquitination sites. With the use of modern instrumentation and various MS-based techniques, peptides and their PTMs can be characterized in a high-throughput manner while still maintaining high sensitivity and specificity. In complement to bottom-up MS, recent advances in MS technology, such as high-field Fourier transform ion cyclotron resonance (FTICR)-mass spectrometry, have permitted the study of intact proteins and their modifications. On-line and off-line protein separation instruments coupled to FTICR-MS allow the characterization of PTMs previously undetectable with bottom-up approaches. The use of unique fragmentation techniques in FTICR-MS provides a viable option for the study of labile modifications. In this chapter, we provide a detailed description of the analytical tools - mass spectrometry in particular - that are used to characterize modifications on peptides and proteins. We also examine the applicability of these mass spectrometric techniques to the study of PTMs on histones via both the bottom-up and top-down proteomics approaches.

Towards the development of an immuno MALDI (iMALDI) mass spectrometry assay for the diagnosis of hypertension.

The renin-angiotensin-aldosterone system (RAAS) plays an essential role in the regulation of plasma volume and arterial blood pressure. One of the most common diseases of the RAAS is the autonomous production of aldosterone by the adrenal glands, caused by either bilateral adrenal hyperplasia or an aldosterone-producing adenoma. This condition, known as primary aldosteronism, is a treatable and often curable form of hypertension. The measurement of plasma renin activity (PRA), as determined by radioimmunoassay for angiotensin I is essential to the diagnosis of primary aldosteronism. However, accurate determination of PRA is often hampered by low plasma concentrations of angiotensin I. Here, we report the use of immuno-MALDI (iMALDI) as a highly sensitive and specific method for the absolute quantitation of angiotensin I in plasma. iMALDI permits concentration determination by affinity-capture of angiotensin I and a stable-isotopically labeled standard (SIS) peptide on immobilized anti-peptide antibodies. The affinity beads are placed on the MALDI target, permitting automated analysis of large numbers of patient samples. Pretreatment of the plasma is not required, and this method is suitable for the accurate determination of angiotensin I in whole plasma. The calibration curve generated using this method was linear over a 50-fold concentration range in plasma, with a correlation coefficient of 0.984. MS/MS sequence confirmation provides absolute specificity. The iMALDI angiotensin I assay, therefore, has the potential to be developed into a method for determining PRA that has advantages in time, in specificity, and in safety.