Identification of concomitant injuries associated with specific spine level fractures in polytrauma patients.

INTRODUCTION: Spine fractures are associated with high energy mechanisms and can lead to substantial morbidity and mortality in the trauma setting. Rapid identification and treatment of these fractures and their associated injuries are paramount in preventing adverse outcomes. The purpose of this study is to identify concomitant skeletal and non-skeletal injuries related to cervical, thoracic, and lumbar fractures. METHODS: A retrospective review of institutional American College of Surgeons (ACS) registry was conducted on 3,399 consecutive trauma patients identifying those with spine fractures from 1/2016-12/2019. Two-hundred ninety patients were included(8.5%) and separated into three groups based on fracture location: eighty-eight cervical(C)-spine, 129thoracic(T)-spine, and 143lumbar(L)-spine. Logistic regression analyses were performed to identify associated injuries, presenting injury severity score(ISS) and Glasgow coma scale(GCS), mechanism of injury, demographic data, substance use, and paralysis for each group. Cox hazard regression was utilized to identify factors associated with inpatient mortality. RESULTS: C-spine fractures were associated with head trauma(OR2.18,p = 0.003),intracranial bleeding (OR2.64,p = 0.001),facial(OR2.25,p = 0.02) and skull fractures(OR3.92,p = 0.001),and cervical cord injuries(OR4.78,p = 0.012). T-spine fractures were associated with rib fractures(OR2.31,p = 0.003). L-spine fractures were associated with rib(OR1.77, p = 0.04), pelvic(OR5.11,p<0.001), tibia/fibula (OR2.31,p = 0.05), and foot/ankle fractures(OR3.32,p = 0.04), thoracic(OR2.43,p = 0.008) and retroperitoneal cavity visceral injuries(OR27.3,p = 0.001). Falls≤6meters were also significantly associated with C-spine fractures(OR1.70,p = 0.04) while falls>6meters were associated with L-spine fractures(OR4.30,p = 0.001). Inpatient mortality risk increased in patients with C-spine fractures(HR4.41,p = 0.002), higher ISS(HR1.05, p<0.001), and lower GCS(HR0.85,p<0.001). Last, patients≥65-years-old were more likely to experience C-spine fractures(OR1.88,p = 0.03). CONCLUSION: Patients who experience fractures of the cervical, thoracic, or lumbar spine are at risk for additional fractures, visceral injury, and/or death. Awareness of the associations between spinal fractures and other injuries can increase diagnostic efficacy, improve patient care, and provide valuable prognostic information. These associations highlight the importance of effective and timely communication and multidisciplinary collaboration.

Minnelide, a prodrug, inhibits cervical cancer growth by blocking HPV-induced changes in p53 and pRb.

HPV-induced cervical cancer is one of the prevalent gynecological cancers world-wide. In the present study, we determined the efficacy of Minnelide, a prodrug which is converted to its active form (Triptolide) in vivo against cervical cancer cells. Our studies show that Triptolide inhibited HPV-16 and HPV-18 positive cells at nanomolar concentrations. Tumor cells treated with Triptolide failed to grow in 3-D cultures in a concentration-dependent manner. Triptolide markedly reduced E6 and E7 transcript levels. Further studies revealed that exposure to Triptolide increased the levels of p53 and pRb. As a consequence, Caspase-3/7 activation and apoptosis was induced in cervical cancer cells by Triptolide. Subsequently, we evaluated the efficacy of Minnelide in xenotransplantation models of cervical cancer. Minnelide at very low doses effectively inhibited the growth of established cervical cancers in all the three animal models tested. Furthermore, Minnelide treatment was more effective when combined with platinum-based chemotherapy. These studies show that Minnelide can be used to inhibit the growth of cervical cancer.

Heat trapping in a nano-layered microenvironment: estimation of temperature by thermal sensing molecules.

We have previously found reversible photo-induced expansion and contraction of organic/inorganic clay hybrids, and even sliding of niobate nano-sheets at the macroscopic level of organic/inorganic niobate hybrids, induced by the molecular photo-isomerization of the polyfluoroalkylated azobenzene derivative (C3F-Azo-C6H) intercalated within the interlayer, which is viewed as an artificial muscle model unit. Based on systematic investigations of the steady state photo-isomerization and transient behavior of the reaction, we comprehended that the phenomena is caused by trapping of excess energy liberated during the isomerization, as well as the relaxation processes upon excitation of azobenzene chromophores in the interlayers of the hybrid. In this paper, quantitative estimation of transient 'heat' trapped in various microenvironments has been studied by each co-intercalation of temperature sensing dye molecules - rhodamine B (RhB) or tris(bipyridine)ruthenium(ii) chloride (Rubpy) with C3F-Azo-C6H within clay (SSA) nano-layers. The amount of dye molecules co-intercalated was kept to trace amounts that did not alter the bi-layered structure of the hybrid. The temperature of the microenvironment surrounding the probe molecules was estimated from the emission lifetime analysis. The evidently reduced emission lifetimes in C3F-Azo-C6H/SSA and C3H-Azo-C6H/SSA hybrids in the film state, indicated the elevation of temperature of the microenvironment upon excitation of the chromophores, which demonstrated our previous hypothesis rationalizing that the high reactivity of isomerization in the hybrid film state is caused by heat trapping via multi-step dissipation of the excess energy. With the hybrid of a hydrocarbon analogue (C3H-Azo-C6H), a distinct difference in temperature gradient was found to show the crucial role of the perfluoroalkyl chain of the surfactant that traps the excess energy to retard its dissipation leading to three-dimensional morphological motion.

Designing Metallic MoO2 Nanostructures on Rigid Substrates for Electrochemical Water Activation.

In situ growth of metallic MoO2 films on fluorine-doped tin oxide (FTO) and MoO2 powder in solution was achieved simultaneously by a simple hydrothermal process employing citric acid as the surfactant. The growth mechanism of MoO2 nanostructures (NSs) at the heterogeneous interface and in homogeneous medium proceeds in a different manner in which seeds grow in a preferred orientation on FTO, whereas they propagate in all directions in solution. The high lattice matching of FTO and MoO2 favours the film growth which could not be obtained on other conventional substrates. The disc morphology of MoO2 nanostructures was changed to other diverse morphology by varying the synthesis conditions, particularly by the addition of nitric acid. A competitive effect of nitric acid and citric acid on the structure direction produced various shapes. The electrochemical water activation studies show that hydrogen-annealed MoO2 is an excellent hydrogen evolution reaction (HER) catalyst with good stability. H-MoO2 film/FTO displays a low onset overpotential of72 mV with a Tafel slope of 84.1 mV dec-1 , whereas the powder form exhibits an onset overpotential of 46 mV with a Tafel slope of 71.6 mV dec-1 . The large active surface area, exposure of fringe facets of (110) and the lesser electrochemical charge-transfer resistance offered by the hydrogen-annealed MoO2 NSs play a major role in the enhanced HER activity.

Retrospective Review on Accuracy: A Pilot Study of Robotically Guided Thoracolumbar/Sacral Pedicle Screws Versus Fluoroscopy-Guided and Computerized Tomography Stealth-Guided Screws.

Introduction Pedicle screw insertion is the mainstay of thora-cic and lumbosacral posterior spinal instrumentation. However, it may be associated with complications such as screw mal-positioning. The purpose of this study was to develop a pilot study to compare the accuracy of robot-guided screw insertion versus hand-guided screw placement for spinal instrumentation. The hand-guided screws were placed with assistance from computerized tomography (CT) stealth guidance or fluoroscopy. Materials and methods A retrospective analysis of medical records was done for all patients that had pedicle screw insertion for instrumentation between the dates of December 2013 and January 2016 with post-screw placement CT imaging. The analysis was conducted on screw accuracy between the two categories based on the Gertzbein-Robbins classification. Results A total of 49 screws were analyzed for accuracy in six patients. There was no statistically significant difference between the accuracy of hand-placed pedicle screws versus the robotically placed screws (p = 0.311). There was no statistically significant difference in blood loss (p = 0.616), length of procedure (p = 0.192), or post-operative length of stay (p = 0.587). Conclusion The findings of our pilot study agree with most prior studies that there was no statistically significant difference in the accuracy of pedicle screw placement between the two methods of screw placement. Therefore, the techniques are equivocal in accuracy. The new technology (robotic-guidance) is as safe as conventional techniques for screw placement. Just like in any surgery, the technique preference should remain surgeon dependent. The results are only from a small sample size in the development of a pilot study so a strong reliance on the data would not be suggested. The study was a preliminary study that will be used as a template and learning process to create a future prospective study to investigate CT stealth and robotically guided screw placement versus "free hand" guided screws.

A rare case of pharyngeal perforation and expectoration of an entire anterior cervical fixation construct.

Anterior cervical discectomy and fusion (ACDF) is a very common surgery performed globally. Although a few cases of expectorating screws or extrusion of screws into the gastrointestinal tract through esophageal perforations have previously been reported, there has not been a case reporting pharyngeal perforation and entire cervical construct extrusion in the literature to date. In this report the authors present the first case involving the extrusion of an entire cervical construct via a tear in the posterior pharyngeal wall. An 81-year-old woman presented to the emergency department (ED) with a complaint of significant cervical pain 5 days after a fall due to a syncopal event. Radiological findings showed severe anterior subluxation of C-2 on C-3 with no spinal cord signal change noted. She underwent ACDF at the C2-3 level utilizing a polyetheretherketone (PEEK) cage, allograft, autograft, and a nontranslational plate with a locking apparatus and expanding screws. The screw placement was satisfactory on postoperative radiography and the Grade II spondylolisthesis of C-2 on C-3 was reduced appropriately with the surgery. The postoperative radiographs obtained demonstrated good instrumentation placement. Three and a half years later the patient returned to the ED having expectorated the entire anterior cervical construct. A CT scan demonstrated the C-2 and C-3 vertebral bodies to be fused posteriorly with an anterior erosive defect within the vertebral bodies and the anterior fusion hardware at the C2-3 level no longer identified. The fiberoptic laryngoscopy demonstrated a 1 × 1 cm area over the importation of the hypopharynx, above the glotic area. The Gastrografin swallowing test ruled out any esophageal tear or fistula and confirmed the presence of a large ulcer on the posterior wall of the oropharynx. To the best of the authors' knowledge, this is the first ever reported case of a tear in the posterior pharyngeal wall along with extrusion of the entire cervical construct after ACDF. This case demonstrates a rare but potentially serious complication of ACDF. Based on the available literature, each case requires separate and distinct treatment from the others.

Synthesis of double-wall nanoscrolls intercalated with polyfluorinated cationic surfactant into layered niobate and their magnetic alignment.

The orientation of nanomaterials with an anisotropic nature such as nanoscrolls is very important for realizing their efficient and sophisticated functions in devices, including nanostructured electrodes in artificial photosynthetic cells. In this study, we successfully synthesized a nanoscroll by intercalation of a cationic polyfluorinated surfactant into the interlayer spaces of layered niobate and successfully controlled its orientation by applying an external magnetic field in water. The exfoliated niobate nanosheets were efficiently rolled-up to form nanoscrolls, which have a fine layered structure (d020 = 3.64 nm), by mixing with heptafluorobutanoylaminoethylhexadecyldimethylammonium bromide (C3F-S) in water, whereas the corresponding hydrocarbon analogue (C3H-S) did not form nanoscrolls. The synthetic yield for the purified and isolated nanoscrolls from the nanosheets was estimated to be 62% by weight. It was confirmed by atomic force microscopy (AFM) that most of the niobate nanosheets (98%) were converted to nanoscrolls. An external magnetic field was applied to the nanoscrolls to force them to align. After the magnetic treatment, the orientation of the nanoscrolls was investigated by small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The non-uniform ring distribution of the SAXS patterns indicates that the nanoscrolls dispersed in water were aligned well on applying the magnetic field. The long axis of the nanoscroll was oriented in the direction of the applied field and long nanoscrolls were aligned more efficiently. When the intercalated C3F-S molecules were removed from the nanoscrolls by treating with an acid, the resultant nanoscrolls did not exhibit magnetic alignment, strongly suggesting that C3F-S plays an important role in the orientation control of the nanoscrolls by the magnetic field.

Early Experience with the TransForm™ Occlusion Balloon Catheter: A Single-Center Study.

BACKGROUND AND OBJECTIVE: Balloon-assisted coil embolization has become an important adjunct in the endovascular treatment of intracranial aneurysms. The management of broad-necked cerebral aneurysms is technically perplexed due to a variety of factors, which include the difficulty in defining the aneurysm-parent vessel interface angiographically and problems in achieving complete aneurysmal occlusion. This could later predispose to regrowth or recanalization. We sought to determine the safety and efficacy of the TransForm™ occlusion balloon catheter (TOBC) for the coiling of intracranial aneurysms at our institute. METHODS: A retrospective review was performed to identify TOBC cases between May 1, 2013, and April 30, 2014. RESULTS: A total of 24 TOBC cases were identified. In 23 cases, the TOBC was used for balloon-remodeled coil embolization, and in 1 case, it was used for vasospasm treatment alone. Out of the total 24 cases in which the TOBC was used, 16 (66.6%) were ruptured aneurysms. Stents were used in 6/23 (26%) cases. In all cases, the balloon could be placed as intended. The inflation and deflation times ranged from 3 to 4 s. No serious complications were noted. In the experience of the authors, the balloon performed the intended role in most cases. CONCLUSIONS: This series shows that the TOBC is feasible, safe and useful in the treatment of cerebral aneurysms. The balloon was traceable to the intended site and the preparation, inflation and deflation times were short. We believe that the TOBC has effective utility in treating broad-necked and small aneurysms.

Anti-epileptic prophylaxis in traumatic brain injury: A retrospective analysis of patients undergoing craniotomy versus decompressive craniectomy.

BACKGROUND: Seizures account for significant morbidity and mortality early in the course of traumatic brain injury (TBI). Although there is sufficient literature suggesting short-term benefits of antiepileptic drugs (AEDs) in post-TBI patients, there has been no study to suggest a time frame for continuing AEDs in patients who have undergone a decompressive craniectomy for more severe TBI. We examined trends in a level-II trauma center in southern California that may provide guidelines for AED treatment in craniectomy patients. METHODS: A retrospective analysis was performed evaluating patients who underwent decompressive craniectomy and those who underwent a standard craniotomy from 2008 to 2012. RESULTS: Out of the 153 patients reviewed, 85 were included in the study with 52 (61%) craniotomy and 33 (39%) craniectomy patients. A total of 78.8% of the craniotomy group used phenytoin (Dilantin), 9.6% used levetiracetam (Keppra), 5.8% used a combination of both, and 3.8% used topiramate (Topamax). The craniectomy group used phenytoin 84.8% and levetiracetam 15.2% of the time without any significant difference between the procedural groups. Craniotomy patients had a 30-day seizure rate of 13.5% compared with 21.2% in craniectomy patients (P = 0.35). Seizure onset averaged on postoperative day 5.86 for the craniotomy group and 8.14 for the craniectomy group. There was no significant difference in the average day of seizure onset between the groups P = 0.642. CONCLUSION: Our study shows a trend toward increased seizure incidence in craniectomy group, which does not reach significance, but suggests they are at higher risk. Whether this higher risk translates into a benefit on being on AEDs for a longer duration than the current standard of 7 days cannot be concluded as there is no significant difference or trend on the onset date for seizures in either group. Moreover, a prospective study will be necessary to more profoundly evaluate the duration of AED prophylaxis for each one of the stated groups.

Remarkable enhancement of the photoreactivity of a polyfluoroalkyl azobenzene derivative in an organic-inorganic nano-layered microenvironment.

Organic-inorganic hybrids composed of polyfluoroalkyl azobenzene surfactant (abbreviated as C3F-Azo-C6H) and inorganic layered compounds are able to undergo reversible three-dimensional morphology changes such as interlayer space changes and nanosheet sliding in a giant scale due to reversible trans-cis isomerization of the azobenzene moiety upon photo-irradiation. In this paper, we have systematically studied the relationship between the layered hybrid microstructures of C3F-Azo-C6H-clay and their photoreactivity for understanding the mechanism of the photo-induced morphology change. The photoreactivity was found to be very much affected by the surrounding microenvironments. As compared with it in solution, the cis-trans photo-isomerization in C3F-Azo-C6H-clay nano-layered film was substantially enhanced with the quantum yield exceeding unity (Φ = 1.9), while the trans-cis isomerization was rather retarded. The corresponding hydrocarbon analogue of the azobenzene surfactant (C3H-Azo-C6H) did not show such an enhancement. The enhancement was discussed in terms of a cooperative effect among adjacent azobenzene moieties along with polyfluoroalkyl chains and the inorganic clay nanosheet to prevent a dissipation of the excess energy being liberated during the photo-isomerization within the nano-layered microenvironment.

Applied field nonequilibrium molecular dynamics simulations of ion exit from a beta-barrel model of the L-type calcium channel.

We present results of applied field nonequilibrium molecular dynamics simulations (AF NEMD) of a minimal beta-barrel model channel intended to represent an L-type calcium channel that suggests a possible relationship between glutamate side chain conformational changes and ion flux in calcium channels. The beta-barrel is used to provide a scaffolding for glutamate side chains and a confinement for electrolyte of dimensions similar to the expected channel structure. It was preloaded with ions to explore relative rates of ion exit for different occupancy configurations. Our simulations with an asymmetrical flexible selectivity filter represented by four glutamate side chains (EEEE), one of which differs in initial dihedrals from the other three, indicate a plausible mechanism for the observed anomalous mole fraction effect seen in calcium channels. Apparent rates of electric field-induced exit from channels preloaded with three Na+ ions are much higher than for channels with one Ca2+ followed by two Na+ ions, consistent with the common notion that Ca2+ block of Na+ current is due to competition between the Ca2+ and Na+ ions for the negatively charged (EEEE) locus. In our model, the Ca2+ ion ligates simultaneously to the four negatively charged glutamate side chains and sterically blocks the permeation pathway. Ca2+-relief of Ca2+-block is suggested by a much higher rate of exit for channels preloaded with three Ca2+ ions than for channels with two Ca2+ ions.

An inverting basket model for AE1 transport.

We describe an "inverting basket" model for transport in the erythrocyte anion exchanger, AE1. The inverting basket is formed by the side chains of three putative key residues, two positively (Lys 826 and Arg 730) and one negatively (Glu 681) charged residue. We have tentatively chosen seven transmembrane helices, TM1, TM2, TM4, TM8, TM10, TM12 and TM13 to form a conical channel using the well-established Glu 681 of TM8 and candidates Lys 826 and Arg 730 of TM12-13 and TM10, respectively, to form the inverting basket. We assume that these residues bind to an anion and shift from outward facing (C(o)) to inward facing (C(i)) conformation without significant backbone movements to transport an anion across the membrane. The transition of the complex (residues and ion) from outward facing (C(o)) to inward facing (C(i)) constitutes one "basket" inversion. The barrier to inversion is composed of two major components: that of the anhydrous complex, which we refer to as a steric energy barrier and a dehydration effect due to the removal of charges in the complex from water in the channel. The steric barrier is dependent on the side chain charge and configuration and on the ion charge and size. The dehydration effect, for our model, ameliorates the steric barrier, in the case of the empty complex but less so for the monovalent and divalent ions. We conclude, that it is possible for a seven-helix bundle to have a steric barrier to basket inversion, but that hydration effects in thin hydrophobic barrier models may be more complex than usually envisioned.