Intraoperative fracture of phacoemulsification sleeve

<p>Abstract</p> <p>Background</p> <p>We describe a case of intraoperative fracture of phacoemulsification sleeve during phacoemulsification surgery.</p> <p>Case presentation</p> <p>Phacoemulsification surgery was performed in the left eye of a 58-year-old lady with grade II nuclear sclerosis & grade I cortical cataract. Towards the end of quadrant removal, there was anterior chamber instability with impaired followability of nuclear fragments. The distal part of the fractured sleeve remained inside the anterior chamber upon removal of the phacoemulsification probe. The retained sleeve was retrieved with a pair of forceps through the corneal incision site, which did not require widening. There was no missing fragments retained intraocularly and the patient had an uneventful recovery with vision of 20/25 at three months post-operatively.</p> <p>Conclusion</p> <p>Phacoemulsification sleeve fracture is an uncommon complication. With early identification of this condition and proper management, major complications can be avoided.</p

Cooling athletes with a spinal cord injury

Cooling strategies that help prevent a reduction in exercise capacity whilst exercising in the heat have received considerable research interest over the past 3 decades, especially in the lead up to a relatively hot Olympic and Paralympic Games. Progressing into the next Olympic/Paralympic cycle, the host, Rio de Janeiro, could again present an environmental challenge for competing athletes. Despite the interest and vast array of research into cooling strategies for the able-bodied athlete, less is known regarding the application of these cooling strategies in the thermoregulatory impaired spinal cord injured (SCI) athletic population. Individuals with a spinal cord injury (SCI) have a reduced afferent input to the thermoregulatory centre and a loss of both sweating capacity and vasomotor control below the level of the spinal cord lesion. The magnitude of this thermoregulatory impairment is proportional to the level of the lesion. For instance, individuals with high-level lesions (tetraplegia) are at a greater risk of heat illness than individuals with lower-level lesions (paraplegia) at a given exercise intensity. Therefore, cooling strategies may be highly beneficial in this population group, even in moderate ambient conditions (~21 °C). This review was undertaken to examine the scientific literature that addresses the application of cooling strategies in individuals with an SCI. Each method is discussed in regards to the practical issues associated with the method and the potential underlying mechanism. For instance, site-specific cooling would be more suitable for an athlete with an SCI than whole body water immersion, due to the practical difficulties of administering this method in this population group. From the studies reviewed, wearing an ice vest during intermittent sprint exercise has been shown to decrease thermal strain and improve performance. These garments have also been shown to be effective during exercise in the able-bodied. Drawing on additional findings from the able-bodied literature, the combination of methods used prior to and during exercise and/or during rest periods/half-time may increase the effectiveness of a strategy. However, due to the paucity of research involving athletes with an SCI, it is difficult to establish an optimal cooling strategy. Future studies are needed to ensure that research outcomes can be translated into meaningful performance enhancements by investigating cooling strategies under the constraints of actual competition. Cooling strategies that meet the demands of intermittent wheelchair sports need to be identified, with particular attention to the logistics of the sport

Heat-related issues and practical applications for Paralympic athletes at Tokyo 2020

International sporting competitions, including the Paralympic Games, are increasingly being held in hot and/or humid environmental conditions. Thus, a greater emphasis is being placed on preparing athletes for the potentially challenging environmental conditions of the host cities, such as the upcoming Games in Tokyo in 2020. However, evidence-based practices are limited for the impairment groups that are eligible to compete in Paralympic sport. This review aims to provide an overview of heat-related issues for Paralympic athletes alongside current recommendations to reduce thermal strain and technological advancements in the lead up to the Tokyo 2020 Paralympic Games. When competing in challenging environmental conditions a number of factors may contribute to an athlete’s predisposition to heightened thermal strain. These include the characteristics of the sport itself (type, intensity, duration, modality and environmental conditions), the complexity and severity of the impairment and classification of the athlete. For heat vulnerable Paralympic athletes, strategies such as the implementation of cooling methods and heat acclimation can be used to combat the increase in heat strain. At an organisational level regulations and specific heat policies should be considered for several Paralympic sports. Both the utilisation of individual strategies and specific heat health policies should be employed to ensure that Paralympics athletes’ health and sporting performance are not negatively affected during competition in the heat at the Tokyo 2020 Paralympic Games

TDP-43 and RNA form amyloid-like myo-granules in regenerating muscle

A dominant histopathological feature in neuromuscular diseases, including amyotrophic lateral sclerosis and inclusion body myopathy, is cytoplasmic aggregation of the RNA-binding protein TDP-43. Although rare mutations in TARDBP-the gene that encodes TDP-43-that lead to protein misfolding often cause protein aggregation, most patients do not have any mutations in TARDBP. Therefore, aggregates of wild-type TDP-43 arise in most patients by an unknown mechanism. Here we show that TDP-43 is an essential protein for normal skeletal muscle formation that unexpectedly forms cytoplasmic, amyloid-like oligomeric assemblies, which we call myo-granules, during regeneration of skeletal muscle in mice and humans. Myo-granules bind to mRNAs that encode sarcomeric proteins and are cleared as myofibres mature. Although myo-granules occur during normal skeletal-muscle regeneration, myo-granules can seed TDP-43 amyloid fibrils in vitro and are increased in a mouse model of inclusion body myopathy. Therefore, increased assembly or decreased clearance of functionally normal myo-granules could be the source of cytoplasmic TDP-43 aggregates that commonly occur in neuromuscular disease

The C9orf72 repeat expansion disrupts nucleocytoplasmic transport

A GGGGCC (G(4)C(2)) hexanucleotide repeat expansion (HRE) in C9ORF72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recent studies support an HRE RNA gain-of-function mechanism of neurotoxicity, and we previously identified protein interactors for the G(4)C(2) RNA including RanGAP1. A candidate-based genetic screen in Drosophila expressing 30 G(4)C(2) repeats identified RanGAP (Drosophila ortholog of human RanGAP1), a key regulator of nucleocytoplasmic transport, as a potent suppressor of neurodegeneration. Enhancing nuclear import or suppressing nuclear export of proteins also suppresses neurodegeneration. RanGAP physically interacts with HRE RNA and is mislocalized in HRE-expressing flies, neurons from C9ORF72 ALS patient-derived induced pluripotent stem cells (iPSNs), and in C9ORF72 patient brain tissue. Nuclear import is impaired as a result of HRE expression in the fly model and in C9ORF72 iPSNs, and these deficits are rescued by small molecules and antisense oligonucleotides targeting the HRE G-quadruplexes. Nucleocytoplasmic transport defects may be a fundamental pathway for ALS and FTD amenable to pharmacotherapeutic intervention