Remarkable Recovery After Severe Gunshot Brain Injury: A Comprehensive Case Study of Functional Rehabilitation.

BACKGROUND Penetrating traumatic brain injury (TBI) caused by gunshots is a rare type of TBI that leads to poor outcomes and high mortality rates. Conducting a formal neuropsychological evaluation concerning a patient's neurologic status during the chronic recovery phase can be challenging. Furthermore, the clinical assessment of survivors of penetrating TBI has not been adequately documented in the available literature. Severe TBI in patients can provide valuable information about the functional significance of the damaged brain regions. This information can help inform our understanding of the brain's intricate neural network. CASE REPORT We present a case of a 29-year-old right-handed man who sustained a left-hemisphere TBI after a gunshot, causing extensive diffuse damage to the left cerebral and cerebellar hemispheres, mainly sparing the right hemisphere. The patient survived. The patient experienced spastic right-sided hemiplegia, facial hemiparesis, left hemiparesis, and right hemianopsia. Additionally, he had severe global aphasia, which caused difficulty comprehending verbal commands and recognizing printed letters or words within his visual field. However, his spontaneous facial expressions indicating emotions were preserved. The patient received a thorough neuropsychological assessment to evaluate his functional progress following a severe TBI and is deemed to have had a favorable outcome. CONCLUSIONS Research on cognitive function recovery following loss of the right cerebral hemisphere typically focuses on pediatric populations undergoing elective surgery to treat severe neurological disorders. In this rare instance of a favorable outcome, we assessed the capacity of the fully developed right hemisphere to sustain cognitive and emotional abilities, such as language.

Tunable entangled photon-pair generation in a liquid crystal.

Liquid crystals, with their ability to self-assemble, strong response to an electric field and integrability into complex systems, are key materials in light-beam manipulation1. The recently discovered ferroelectric nematic liquid crystals2,3 also have considerable second-order optical nonlinearity, making them a potential material for nonlinear optics4,5. Their use as sources of quantum light could considerably extend the boundaries of photonic quantum technologies6. However, spontaneous parametric down-conversion, the basic source of entangled photons7, heralded single photons8 and squeezed light9, has so far not been observed in liquid crystals-or in any liquids or organic materials. Here we implement spontaneous parametric down-conversion in a ferroelectric nematic liquid crystal and demonstrate electric-field tunable broadband generation of entangled photons, with an efficiency comparable to that of the best nonlinear crystals. The emission rate and polarization state of photon pairs is markedly varied by applying a few volts or twisting the molecular orientation along the sample. A liquid-crystal source enables a special type of quasi-phase matching10, which is based on the molecular twist structure and is therefore reconfigurable for the desired spectral and polarization properties of photon pairs. Such sources promise to outperform standard nonlinear optical materials in terms of functionality, brightness and the tunability of the generated quantum state. The concepts developed here can be extended to complex topological structures, macroscopic devices and multi-pixel tunable quantum light sources.

Impact of Intracranial Hypertension on Outcome of Severe Traumatic Brain Injury Pediatric Patients: A 15-Year Single Center Experience.

Background: Intracranial hypertension (IC-HTN) is significantly associated with higher risk for an unfavorable outcome in pediatric trauma. Intracranial pressure (ICP) monitoring is widely becoming a standard of neurocritical care for children. Methods: The present study was designed to evaluate influences of IC-HTN on clinical outcomes of pediatric TBI patients. Demographic, injury severity, radiologic characteristics were used as possible predictors of IC-HTN or of functional outcome. Results: A total of 118 pediatric intensive care unit (PICU) patients with severe TBI (sTBI) were included. Among sTBI cases, patients with GCS < 5 had significantly higher risk for IC-HTN and for mortality. Moreover, there was a statistically significant positive correlation between IC-HTN and severity scoring systems. Kaplan−Meier analysis determined a significant difference for good recovery among patients who had no ICP elevations, compared to those who had at least one episode of IC-HTN (log-rank chi-square = 11.16, p = 0.001). A multivariable predictive logistic regression analysis distinguished the ICP-monitored patients at risk for developing IC-HTN. The model finally revealed that higher ISS and Helsinki CT score increased the odds for developing IC-HTN (p < 0.05). Conclusion: The present study highlights the importance of ICP-guided clinical practices, which may lead to increasing percentages of good recovery for children.

Aquatic toxicity and mode of action of CdS and ZnS nanoparticles in four microalgae species.

This study reports the differences in toxic action between cadmium sulfide (CdS) and zinc sulfide (ZnS) nanoparticles (NPs) prepared by recently developed xanthate-mediated method. The aquatic toxicity of the synthesized NPs on four marine microalgae species was explored. Growth rate, esterase activity, membrane potential, and morphological changes of microalgae cells were evaluated using flow cytometry and optical microscopy. CdS and ZnS NPs demonstrated similar level of general toxicity and growth-rate inhibition to all used microalgae species, except the red algae P. purpureum. More specifically, CdS NPs caused higher inhibition of growth rate for C. muelleri and P. purpureum, while ZnS NPs were more toxic for A. ussuriensis and H. akashiwo species. Our findings suggest that the sensitivity of different microalgae species to CdS and ZnS NPs depends on the chemical composition of NPs and their ability to interact with the components of microalgal cell-wall. The red microalga was highly resistant to ZnS NPs most likely due to the presence of phycoerythrin proteins in the outer membrane bound Zn2+ cations defending their cells from further toxic influence. The treatment with CdS NPs caused morphological changes and biochemical disorder in all tested microalgae species. The toxicity of CdS NPs is based on their higher photoactivity under visible light irradiation and lower dissociation in water, which allows them to generate more reactive oxygen species and create a higher risk of oxidative stress to aquatic organisms. The results of this study contribute to our understanding of the parameters affecting the aquatic toxicity of semiconductor NPs and provide a basis for further investigations.

Mechanisms of resistance to fluoroquinolones in Coxiella burnetii.

Mechanisms of resistance to quinolones were investigated in two in vitro DNA gyrase mutant Coxiella burnetii strains. Accumulation of pefloxacin was found to be lower in resistant strains than in susceptible strains. Pre-incubation with carbonyl cyanide m-chlorophenylhydrazone had no apparent effect on intracellular quinolone fluorescence, indicating that an active efflux mechanism is not responsible for the decrease of pefloxacin accumulation. No differences were detected between the strains after outer membrane protein analysis. Decreased accumulation was found in all strains at acidic pH. It is possible that, apart from the mutation-induced mechanism of resistance, a pH-related mechanism is involved in the drug accumulation process.