Point-of-Care Ultrasound in Airway Evaluation and Management: A Comprehensive Review.

Airway management is a common and critical procedure in acute settings, such as the Emergency Department (ED) or Intensive Care Unit (ICU) of hospitals. Many of the traditional physical examination methods have limitations in airway assessment. Point-of-care ultrasound (POCUS) has emerged as a promising tool for airway management due to its familiarity, accessibility, safety, and non-invasive nature. It can assist physicians in identifying relevant anatomy of the upper airway with objective measurements of airway parameters, and it can guide airway interventions with dynamic real-time images. To date, ultrasound has been considered highly accurate for assessment of the difficult airway, confirmation of proper endotracheal intubation, prediction of post-extubation laryngeal edema, and preparation for cricothyrotomy by identifying the cricothyroid membrane. This review aims to provide a comprehensive overview of the key evidence on the use of ultrasound in airway management. Databases including PubMed and Embase were systematically searched. A search strategy using a combination of the term "ultrasound" combined with several search terms, i.e., "probe", "anatomy", "difficult airway", "endotracheal intubation", "laryngeal edema", and "cricothyrotomy" was performed. In conclusion, POCUS is a valuable tool with multiple applications ranging from pre- and post-intubation management. Clinicians should consider using POCUS in conjunction with traditional exam techniques to manage the airway more efficiently in the acute setting.

Influence of Study Composition on the Efficacy of Sleep Detection Using Actigraphy.

Wearable actigraphy sensors have been useful tools for unobtrusive monitoring of sleep. The influence of the composition and characteristics of study groups such as normal sleep versus sleep disorders affecting the efficacy of sleep assessment using actigraphy has not been fully examined. In this study, we present multi-variate sleep models using actigraphy features obtained from wrist-worn sensors and evaluate the efficacy of sleep detection compared to the overnight polysomnography from two unique datasets: overnight actigraphy recordings in a control population of young healthy individuals (n=31) and 24-hour actigraphy recordings in a more heterogeneous population (n=27) comprised of normal and abnormal sleepers. We evaluate the performance of actigraphy derived logistic regression (LR) and random forest (RF) sleep models for both intra-dataset and inter-dataset training and cross-validation. Both the LR and RF sleep models for the healthy sleep dataset show an area under the receiver operating characteristic (AUROC) of 0.85±0.02 in the control sleep dataset among 50 random splits of training and testing evaluations. We find the AUROC performance from the heterogeneous sleep dataset involving sleep disorders to be relatively lower as 0.74±0.05 and 0.80±0.03 for LR and RF sleep models, respectively. Optimal sleep models trained using heterogeneous datasets perform very well when tested with the normal sleep dataset producing accuracy of ∼92%. Our study supports that using a more diverse training set benefits the sleep classifier model to be more generalizable for both healthy and abnormal sleepers.

Nanodisc scaffold peptide (NSPr) replaces detergent by reconstituting acyl-CoA:cholesterol acyltransferase 1 into peptidiscs.

To conduct biochemical studies in vitro, membrane proteins (MPs) must be solubilized with detergents. While detergents are great tools, they can also inhibit the biological activity and/or perturb oligomerization of individual MPs. Nanodisc scaffold peptide (NSPr), an amphipathic peptide analog of ApoA1, was recently shown to reconstitute detergent solubilized MPs into peptidiscs in vitro. Acyl-coenzyme A:cholesterol acyltransferase 1 (ACAT1), also known as sterol O-acyltransferase 1 (SOAT1), plays a key role in cellular cholesterol storage in various cell types and is a drug target to treat multiple human diseases. ACAT1 contains nine transmembrane domains (TMDs) and primarily forms a homotetramer in vitro and in intact cells; deletion of the N-terminal dimerization domain produces a homodimer with full retention in catalytic activity. ACAT1 is prone to inactivation by numerous detergents. Here we pursued the use of NSPr to overcome the detergent-induced inactivation of ACAT1 by generating near detergent-free ACAT1 peptidiscs. Based on native-PAGE analysis, we showed that NSPr reconstitutes ACAT1 into soluble peptidiscs, in which ACAT1 exists predominantly in oligomeric states greater than a homotetramer. The formation of these higher-order oligomeric states was independent of the N-terminal dimerization domain, suggesting that the oligomerization is mediated through hydrophobic interactions of multiple ACAT1 subunits. ACAT1 peptidiscs were still susceptible to heat-mediated inactivation, presumably due to the residual detergent (CHAPS) bound to ACAT1. We then conditioned ACAT1 with phosphatidylcholine (PC) to replace CHAPS prior to the formation of ACAT1 peptidiscs. The results showed, when PC was included, ACAT1 was present mainly in higher-order oligomeric states with greater enzymatic activity. With PC present, the enzymatic activity of ACAT1 peptidiscs was protected from heat-mediated inactivation. These results support the use of NSPr to create a near detergent-free solution of ACAT1 in peptidiscs for various in vitro studies. Our current results also raise the possibility that, under certain conditions, ACAT1 may form higher-order oligomeric states in vivo.

Mycoplasma-induced pustulosis with perifollicular involvement.

Mycoplasma pneumoniae-induced rash and mucositis (MIRM) is a disease characterized by mucosal involvement with variable cutaneous manifestations induced by M. pneumoniae infection. Previously reported rash morphologies include vesiculobullous, targetoid, papular, macular, and morbilliform lesions. Pustulosis is a rare presentation of MIRM that has been described only once before in the literature to our knowledge. We report a case of a 13-year-old boy presenting with a pustular skin eruption induced by Mycoplasma infection. Ours' is the second report of MIRM, to our knowledge, presenting with pustulosis and the first, to our knowledge, to first to describe the histopathologic finding of perifollicular neutrophilic infiltration in MIRM.

Lamellar ichthyosis in a female neonate without a collodion membrane.

The term, autosomal recessive congenital ichthyosis (ARCI), describes a group of rare genetic skin diseases of cornification involving hyperkeratotic scaling at birth. The defective skin barrier function may lead to dehydration, body temperature instability, and high susceptibility to infections. In most cases of ARCI, neonates are born with a collodion membrane covering the body, often presenting with ectropion and eclabium. We report a premature female neonate presenting with hyperkeratotic scaling at birth without a collodion membrane. She was managed with placement in a humidified isolette, prophylactic antibiotics, dilute bleach baths, petrolatum ointment, and artificial eye drops. By the fourth week of life, there was marked improvement in her skin with the large, brown, plate-like scales on the trunk and extremities becoming lighter in color and finer in appearance. The ichthyosis genetic panel showed mutations in the ABCA12 gene resulting in the lamellar ichthyosis phenotype of ARCI. Our literature review revealed at least 28 patients with ARCI who were not born as collodion babies. Although collodion babies are a hallmark of most ARCI cases, clinicians should be aware of neonates with ARCI born without a collodion membrane and expedite appropriate workup and treatment.

Cascading elastic perturbation in Japan due to the 2012 M w 8.6 Indian Ocean earthquake.

Since the discovery of extensive earthquake triggering occurring in response to the 1992 M w (moment magnitude) 7.3 Landers earthquake, it is now well established that seismic waves from earthquakes can trigger other earthquakes, tremor, slow slip, and pore pressure changes. Our contention is that earthquake triggering is one manifestation of a more widespread elastic disturbance that reveals information about Earth's stress state. Earth's stress state is central to our understanding of both natural and anthropogenic-induced crustal processes. We show that seismic waves from distant earthquakes may perturb stresses and frictional properties on faults and elastic moduli of the crust in cascading fashion. Transient dynamic stresses place crustal material into a metastable state during which the material recovers through a process termed slow dynamics. This observation of widespread, dynamically induced elastic perturbation, including systematic migration of offshore seismicity, strain transients, and velocity transients, presents a new characterization of Earth's elastic system that will advance our understanding of plate tectonics, seismicity, and seismic hazards.

Tectal pineal cyst in a 1-year-old girl.

Glial cysts of the pineal gland can frequently be found in adults and children, but only rarely do they enlarge to become clinically relevant. We report a unique presentation of a pineal cyst in the midbrain tectum of a 16-month-old girl who initially presented with ptosis and strabismus. Preoperative imaging studies and intraoperative findings revealed no continuity between the tectal cyst and the pineal gland proper. We surmise that this tectal pineal cyst may have arisen from duplicated pineal gland tissue.

Less invasive pedicled omental-cranial transposition in pediatric patients with moyamoya disease and failed prior revascularization.

BACKGROUND: Patients with moyamoya disease and progressive neurological deterioration despite previous revascularization pose a major treatment challenge. Many have exhausted typical sources for bypass or have ischemia in areas that are difficult to reach with an indirect pedicled flap. Omental-cranial transposition has been an effective, but sparingly used technique because of its associated morbidity. OBJECTIVE: We have refined a laparoscopic method of harvesting an omental flap that preserves its gastroepiploic arterial supply. METHODS: The pedicled omentum can be lengthened as needed by dividing it between the vascular arcades. It is transposed to the brain via skip incisions. The flap can be trimmed or stretched to cover ischemic areas of the brain. The cranial exposure is performed in parallel with pediatric surgeons. We performed this technique in 3 pediatric patients with moyamoya disease (aged 5-12 years) with previous superficial temporal artery to middle cerebral artery bypasses and progressive ischemic symptoms. In 1 patient, we transposed omentum to both hemispheres. RESULTS: Blood loss ranged from 75 to 250 mL. After surgery, patients immediately tolerated a diet and were discharged in 3 to 5 days. The ischemic symptoms of all 3 children resolved within 3 months postoperatively. Magnetic resonance imaging at 1 year showed improved perfusion and no new infarcts. Angiography showed excellent revascularization of targeted areas and patency of the donor gastroepiploic artery. CONCLUSION: Laparoscopic omental harvest for cranial-omental transposition can be performed efficiently and safely. Patients with moyamoya disease appear to tolerate this technique much better than laparotomy. With this method, we can achieve excellent angiographic revascularization and resolution of ischemic symptoms.

CNTF-mediated protection of photoreceptors requires initial activation of the cytokine receptor gp130 in Müller glial cells.

Ciliary neurotrophic factor (CNTF) acts as a potent neuroprotective agent in multiple retinal degeneration animal models. Recently, CNTF has been evaluated in clinical trials for the inherited degenerative disease retinitis pigmentosa (RP) and for dry age-related macular degeneration (AMD). Despite its potential as a broad-spectrum therapeutic treatment for blinding diseases, the target cells of exogenous CNTF and its mechanism of action remain poorly understood. We have shown previously that constitutive expression of CNTF prevents photoreceptor death but alters the retinal transcriptome and suppresses visual function. Here, we use a lentivirus to deliver the same secreted human CNTF used in clinical trials to a mouse model of RP. We found that low levels of CNTF halt photoreceptor death, improve photoreceptor morphology, and correct opsin mislocalization. However, we did not detect corresponding improvement of retinal function as measured by the electroretinogram. Disruption of the cytokine receptor gp130 gene in Müller glia reduces CNTF-dependent photoreceptor survival and prevents phosphorylation of STAT3 and ERK in Müller glia and the rest of the retina. Targeted deletion of gp130 in rods also demolishes neuroprotection by CNTF and prevents further activation of Müller glia. Moreover, CNTF elevates the expression of LIF and endothelin 2, thus positively promoting Müller and photoreceptor interactions. We propose that exogenous CNTF initially targets Müller glia, and subsequently induces cytokines acting through gp130 in photoreceptors to promote neuronal survival. These results elucidate a cellular mechanism for exogenous CNTF-triggered neuroprotection and provide insight into the complex cellular responses induced by CNTF in diseased retinas.

Microsurgical management of distal anterior cerebral artery aneurysms: from basic to complex, a video review of four cases.

BACKGROUND: Distal anterior cerebral artery (DACA) aneurysms represent 2-9 % of intracranial aneurysms. They are often more amenable to surgical rather than endovascular treatment due to the size of parent vessels. METHOD: We illustrate surgical approaches for DACA aneurysms arising from different segments of the anterior cerebral artery. Cases range from simple unruptured aneurysms to complex ruptured aneurysms requiring reconstruction and intracranial bypass. CONCLUSION: The interhemispheric approach typically provides an adequate surgical corridor for surgical clipping of DACA aneurysms. Patient positioning, image guidance, and preoperative angiography help maximize safety and efficacy of surgery.

Use of high-dose oral bisphosphonate therapy for symptomatic fibrous dysplasia of the skull.

Fibrous dysplasia of the bone in adults is a rare anomaly of skeletal development caused by a defect in differentiation of osteoblasts. This condition is associated with bone pain, bone deformity, and an increased incidence of fracture. Involvement of the skull is associated with headache along with dysmorphic features. Until recently, the principal treatment has been resection or fracture repair, although the latter is often palliative at best. However, new insight into the molecular mechanism of fibrous dysplasia has led to the use of bisphosphonates to treat this disease. The authors examined the effects of high-dose oral alendronate (40 mg daily) for 6 months on 3 adult patients with intractable headache due to fibrous dysplasia of the skull. Each patient had disease processes not amenable to surgery. The patients underwent clinical follow-up at 1, 3, and 6 months. Their pain levels were documented at each visit by using a visual analog scale. All 3 patients demonstrated a significant decrease in pain levels and became independent of scheduled analgesics. Tumor bulk did not progress during this interval in any patient. Overall, alendronate was tolerated well, although in 1 patient it was discontinued early due to esophagitis. High-dose oral bisphosphonate therapy is an alternative therapeutic option for the palliative treatment of patients with fibrous dysplasia of the skull.