sn-spMF: matrix factorization informs tissue-specific genetic regulation of gene expression.

Genetic regulation of gene expression, revealed by expression quantitative trait loci (eQTLs), exhibits complex patterns of tissue-specific effects. Characterization of these patterns may allow us to better understand mechanisms of gene regulation and disease etiology. We develop a constrained matrix factorization model, sn-spMF, to learn patterns of tissue-sharing and apply it to 49 human tissues from the Genotype-Tissue Expression (GTEx) project. The learned factors reflect tissues with known biological similarity and identify transcription factors that may mediate tissue-specific effects. sn-spMF, available at https://github.com/heyuan7676/ts_eQTLs , can be applied to learn biologically interpretable patterns of eQTL tissue-specificity and generate testable mechanistic hypotheses.

Tree stand falls: A persistent cause of neurological injury in hunting.

AIM: To characterize and compare our current series of patients to prior reports in order to identify any changes in the incidence of neurological injury related to hunting accidents in Rochester, New York. METHODS: All tree stand-related injuries referred to our regional trauma center from September 2003 through November 2011 were reviewed. Information was obtained from the hospital's trauma registry and medical records were retrospectively reviewed for data pertaining to the injuries. RESULTS: Fifty-four patients were identified. Ninety-six percent of patients were male with a mean age of 47.9 years (range 15-69). The mean Injury Severity Score was 12.53 ± 1.17 (range 2-34). The average height of fall was 18.2 feet (range 4-40 feet). All patients fell to the ground with the exception of one who landed on rocks, and many hit the tree or branches on the way down. A reason for the fall was documented in only 13 patients, and included tree stand construction (3), loss of balance (3), falling asleep (3), structural failure (2), safety harness breakage (3) or light-headedness (1). The most common injuries were spinal fractures (54%), most commonly in the cervical spine (69%), followed by the thoracic (38%) and lumbar (21%) spine. Eight patients required operative repair. Head injuries occurred in 22%. Other systemic injuries include rib/clavicular fractures (47%), pelvic fractures (11%), solid organ injury (23%), and pneumothorax or hemothorax (19%). No patient deaths were reported. The average hospital length of stay was 6.56 ± 1.07 d. Most patients were discharged home without (72%) or with (11%) services and 17% required rehabilitation. CONCLUSION: Falls from hunting tree stands are still common, with a high rate of neurological injury. Compared to a decade ago we have made no progress in preventing these neurological injuries, despite an increase in safety advances. Neurosurgeons must continue to advocate for increased safety awareness and participate in leadership roles to improve outcomes for hunters.

Neurologic injury in snowmobiling.

BACKGROUND: Snowmobiles are increasingly popular recreational, all-terrain utility vehicles that require skill and physical strength to operate given their inherent maneuverability, acceleration, and top speed capabilities. These same characteristics increase the risk of injury with the operation of these vehicles, particularly neurological injury. We characterize our series of 107 patients involved in snowmobiling accidents. METHODS: From January 2004 to January 2012, all snowmobiling-related injuries referred to our regional trauma center were reviewed. Information had been recorded in the hospital's trauma registry and medical records were retrospectively reviewed for data pertaining to the injuries, with particular emphasis on neurological injuries and any associated details. RESULTS: A total of 107 patients were identified. Ninety percent of injured riders were male. The mean age was 34.4 years (range 10-70), with 7% younger than age 16. The mean Injury Severity Score was 12.0 ± 0.69 (range 1-34). Although not documented in all patients, alcohol use was found in 7.5% of the patients and drug use found in one patient. Documentation of helmet use was available for only 31 of the patients; of which 13% were not helmeted. Causes included being thrown, flipped, or roll-over (33%), striking a stationary object (27%), being struck by a snowmobile (9%), striking another snowmobile (5.5%) or a car, train, or truck (5.5%), being injured by the machine itself (9%), other (2%) or unspecified (18%). Head injuries occurred in 35% patients, including concussion, subarachnoid hemorrhage, subdural hematoma, contusion, and facial/skull fracture. Spinal fractures occurred in 21% of the patients. Fractures to the thoracic spine were the most common (50%), followed by the cervical (41%) and lumbar (36%) spine. There were also three brachial plexus injuries, one tibial nerve injury, and one internal carotid artery dissection. Average length of stay was 4.98 ± 0.56 days. Disposition was home (78%), home with services (12%), rehabilitation placement (9%), and one death. Details regarding other systemic injuries will also be reviewed. CONCLUSIONS: Snowmobiles are a significant source of multi-trauma, particularly neurological injury. Neurosurgeons can play key roles in advocating for neurological safety in snowmobiling.

Straight from the horse's mouth: neurological injury in equestrian sports.

OBJECTIVES: Equestrian sports can result in a variety of injuries to the nervous system due to many factors. We describe our series of 80 patients with injuries sustained during participation in equestrian sports. METHODS AND RESULTS: All patients seen at the regional trauma center with injuries associated with equestrian sports between 2003 and 2011 were reviewed; 80 patients were identified. Fifty-four per cent were female and the average age was 37 years (2·2-79·3). The mean injury severity score (ISS) was 9·9 ± 0·7. Only two patients had documented helmet use. Glasgow coma score (GCS) was 15 in 93% of patients. The most common neurosurgical injuries were to the cranial vault (28%), including concussions, intracranial hematomas and hemorrhages, and skull, facial, and spine fractures (10%), with the majority (63%) being transverse process fractures. The mechanisms of injury varied: 55% were kicked or stepped on, 28% were thrown or fell off, and 21% were injured by the horse falling on them. The causes ranged from carelessness and lack of attention to animal factors including inadequate training of horses and animal fear. Fourteen per cent required surgery. There were no mortalities and average length of stay was 3·7 ± 0·35 days. All patients were discharged home with 95% requiring no services. DISCUSSION: Equestrian sports convey special risks for its participants. With proper protection and precautions, a decrease in the incidence of central nervous system injuries may be achieved. Neurosurgeons can play key roles in advocating for neurologic safety in equestrian sports.