The flight response impairs cytoprotective mechanisms by activating the insulin pathway.

An animal's stress response requires different adaptive strategies depending on the nature and duration of the stressor. Whereas acute stressors, such as predation, induce a rapid and energy-demanding fight-or-flight response, long-term environmental stressors induce the gradual and long-lasting activation of highly conserved cytoprotective processes1-3. In animals across the evolutionary spectrum, continued activation of the fight-or-flight response weakens the animal's resistance to environmental challenges4,5. However, the molecular and cellular mechanisms that regulate the trade-off between the flight response and long-term stressors are poorly understood. Here we show that repeated induction of the flight response in Caenorhabditis elegans shortens lifespan and inhibits conserved cytoprotective mechanisms. The flight response activates neurons that release tyramine, an invertebrate analogue of adrenaline and noradrenaline. Tyramine stimulates the insulin-IGF-1 signalling (IIS) pathway and precludes the induction of stress response genes by activating an adrenergic-like receptor in the intestine. By contrast, long-term environmental stressors, such as heat or oxidative stress, reduce tyramine release and thereby allow the induction of cytoprotective genes. These findings demonstrate that a neural stress hormone supplies a state-dependent neural switch between acute flight and long-term environmental stress responses and provides mechanistic insights into how the flight response impairs cellular defence systems and accelerates ageing.

A Top-Down Proteomic Assay to Evaluate KRAS4B-Compound Engagement.

Development of new targeted inhibitors for oncogenic KRAS mutants may benefit from insight into how a given mutation influences the accessibility of protein residues and how compounds interact with mutant or wild-type KRAS proteins. Targeted proteomic analysis, a key validation step in the KRAS inhibitor development process, typically involves both intact mass- and peptide-based methods to confirm compound localization or quantify binding. However, these methods may not always provide a clear picture of the compound binding affinity for KRAS, how specific the compound is to the target KRAS residue, and how experimental conditions may impact these factors. To address this, we have developed a novel top-down proteomic assay to evaluate in vitro KRAS4B-compound engagement while assessing relative quantitation in parallel. We present two applications to demonstrate the capabilities of our assay: maleimide-biotin labeling of a KRAS4BG12D cysteine mutant panel and treatment of three KRAS4B proteins (WT, G12C, and G13C) with small molecule compounds. Our results show the time- or concentration-dependence of KRAS4B-compound engagement in context of the intact protein molecule while directly mapping the compound binding site.

Spin-Crossing in the (Z)-Selective Alkyne Semihydrogenation Mechanism Catalyzed by Mo3S4 Clusters: A Density Functional Theory Exploration.

Semihydrogenation of internal alkynes catalyzed by the air-stable imidazolyl amino [Mo3S4Cl3(ImNH2)3]+ cluster selectively affords the (Z)-alkene under soft conditions in excellent yields. Experimental results suggest a sulfur-based mechanism with the formation of a dithiolene adduct through interaction of the alkyne with the bridging sulfur atoms. However, computational studies indicate that this mechanism is unable to explain the experimental outcome: mild reaction conditions, excellent selectivity toward the (Z)-isomer, and complete deuteration of the vinylic positions in the presence of CD3OD and CH3OD. An alternative mechanism that explains the experimental results is proposed. The reaction begins with the hydrogenation of two of the Mo3(µ3-S)(µ-S)3 bridging sulfurs to yield a bis(hydrosulfide) intermediate that performs two sequential hydrogen atom transfers (HAT) from the S-H groups to the alkyne. The first HAT occurs with a spin change from singlet to triplet. After the second HAT, the singlet state is recovered. Although the dithiolene adduct is more stable than the hydrosulfide species, the large energy required for the subsequent H2 addition makes the system evolve via the second alternative pathway to selectively render the (Z)-alkene with a lower overall activation barrier.

Inhibition of Ras/Raf/MEK/ERK Pathway Signaling by a Stress-Induced Phospho-Regulatory Circuit.

Ras pathway signaling plays a critical role in cell growth control and is often upregulated in human cancer. The Raf kinases selectively interact with GTP-bound Ras and are important effectors of Ras signaling, functioning as the initiating kinases in the ERK cascade. Here, we identify a route for the phospho-inhibition of Ras/Raf/MEK/ERK pathway signaling that is mediated by the stress-activated JNK cascade. We find that key Ras pathway components, the RasGEF Sos1 and the Rafs, are phosphorylated on multiple S/TP sites in response to JNK activation and that the hyperphosphorylation of these sites renders the Rafs and Sos1 unresponsive to upstream signals. This phospho-regulatory circuit is engaged by cancer therapeutics, such as rigosertib and paclitaxel/Taxol, that activate JNK through mitotic and oxidative stress as well as by physiological regulators of the JNK cascade and may function as a signaling checkpoint to suppress the Ras pathway during conditions of cellular stress.

Use of pedicled flaps after oncologic resections in pediatric patients.

The aim of this study is to review the indications of pedicled flaps and analyze the results. A observational retrospective study of under 18-year-old oncology patients who required reconstructive surgery with pedicled flaps between 2011 and 2022 was performed. Demographic and clinical variables, indications, complications, and outcomes were collected. 236 patients were reviewed and 13 met inclusion criteria, eight girls and five boys (mean age: 10.6 years). Indications were Ewing's sarcoma (5), osteosarcoma (5), neuroblastoma, desmoid tumor, and neurofibroma. Preoperative PET-CT, MRI and bone scintigraphy were performed. The flaps were used on costal and extremity reconstruction: latissimus dorsi (5), pectoralis (2), medial gastrocnemius (2), combined latissimus dorsi, trapezius and serratus muscle, biceps femoris, fascio-neuro-cutaneous saphenous and cutaneous advancement-rotation. Two were performed on allograft and eight on prosthesis. All allowed immediate and complete closure. Six patients received intraoperative radiotherapy. One flap infection and two vascular complications were reported, a total necrosis, which required a new flap, and a partial necrosis, treated with a local plasty. Chemotherapy was resumed after 21 days (15-31). Mean follow-up time was 5.34 years. Flaps are an effective therapeutic option allowing reconstruction of large defects after pediatric oncologic surgeries. The most frequent complication was vascular.

Deepening in the understanding of the role of collagen subunits on the differential molecular arrangement of P. glauca and M. merluccius marine collagens.

Decades of extensive efforts on marine collagen extraction and characterization allowed to recognize the unique and excellent characteristics of marine collagen offering advantages over that obtained from terrestrial sources. However, not all marine collagens have the same biochemical characteristics; understanding those at molecular and supramolecular level, is crucial for optimal design of applications. One relevant aspect of collagen characterization is the analysis of its different subunits (α-chains) and their intermolecular cross-links (ß- and γ-components), which ultimately determine the specific functions of a particular collagen. Collagens from a teleost and an elasmobranch species were analyzed to understand the influence of their subunit composition and intermolecular crosslinking pattern on their different physicochemical behaviour. For comparative purposes a commercial mammal collagen was included in the study. Although electrophoretic profiles showed the typical composition of type I collagen for hake, blue shark and calf collagen, molar ratios of their α-chains were different indicating a different degree of dimerization of their α2-chains with implications in the presence of a different crosslinking degree pattern. Electrophoresis, amino acid composition, hydrophobicity (RP-HPLC) and molecular weight analysis (GPC-HPLC) results, besides a peptide mapping and an antioxidant activity study of the resultant peptides, would help to understand the role of different subunit collagen composition and different crosslinking pattern in the conformation of a differential quaternary supramolecular structure within different species and its biofunctional implications. The experiments developed would allow to progress in the valorization potential of fish discards and byproducts to explore commercial uses of collagens from marine origin.

Autocrine insulin pathway signaling regulates actin dynamics in cell wound repair.

Cells are exposed to frequent mechanical and/or chemical stressors that can compromise the integrity of the plasma membrane and underlying cortical cytoskeleton. The molecular mechanisms driving the immediate repair response launched to restore the cell cortex and circumvent cell death are largely unknown. Using microarrays and drug-inhibition studies to assess gene expression, we find that initiation of cell wound repair in the Drosophila model is dependent on translation, whereas transcription is required for subsequent steps. We identified 253 genes whose expression is up-regulated (80) or down-regulated (173) in response to laser wounding. A subset of these genes were validated using RNAi knockdowns and exhibit aberrant actomyosin ring assembly and/or actin remodeling defects. Strikingly, we find that the canonical insulin signaling pathway controls actin dynamics through the actin regulators Girdin and Chickadee (profilin), and its disruption leads to abnormal wound repair. Our results provide new insight for understanding how cell wound repair proceeds in healthy individuals and those with diseases involving wound healing deficiencies.

The effect of cilostazol on the platelet-derived growth factor-beta/beta isoform reduction on venous hyperplasia in an experimental balloon-induced injury model.

BACKGROUND: Intimal hyperplasia is the response to endothelial injury. Platelet-derived growth factor is released early and favors the formation of intimal hyperplasia. Although multiple treatments, from open surgery to endovascular techniques, have been used they remain controversial. There is currently interest in developing pharmacological strategies to address this pathology. Local vascular inflammation induced by vessel barotrauma generates intimal hyperplasia due to mechanical stress over the venous endothelium. Cilostazol is a selective phosphodiesterase type 3 (PDE3) selective inhibitor with a regulatory effect over intimal hyperplasia. The objective was to investigate cilostazol's role in inhibiting smooth muscle cell proliferation due to changes in the expression and release of PDGF-BB isoform and the effect on developing IH using an experimental model of vascular barotrauma (balloon-induced injury model). METHODS: We included 12 New Zealand rabbits. The balloon-induced injury model (BIIM) and experimental group cilostazol (20 mg/kg/day) included 6 rabbits each. Contralateral veins from 6 rabbits used in BIIM model has been taken as control group. We measured and compared the expression of PDGF-BB and the development of IH. A pathologist board chooses a PDGFRα antibody to localized its expression by immunohistochemistry analysis. Subsequently, using an automated immunohistochemical staining machine, the PDGFR expression was evaluated using a Zeiss Primo Star 4 light microscope. RESULTS: The measurement obtained in the intimal layer was: 126.12 µm2 in the CG, 232 µm2 in the BIIM group, and 178 µm2 in the EG. A statistically significant difference was observed. Baseline serum concentrations of PDGF-BB in the BIIM group were 0.22 pg/mL. At 12 h 0.42 pg/mL, and 0.17 pg/mL at seven days. In the experimental group, the basal levels were 0.33 pg/mL. With the use of cilostazol, a lower peak was obtained at 12 h (0.08 pg/mL). This difference was statistically significant. CONCLUSIONS: Cilostazol induced a significant reduction of IH caused by barotrauma in the venous endothelium, which correlates with decrease in the PDGF-BB in serum. This could be attributed to the pharmacologic effect on PDGFR expression.

Determination of antioxidant activity by in situ synthesis of AgNPs using in-tube SPME coupled on-line to capillary liquid chromatography.

A chromatographic system based on in-tube SPME coupled to capillary LC-DAD has been used to study the synthesis of silver nanoparticles using polyphenols in different scenarios: excess of the reducing agent or of the silver salt, addition of the cationic surfactants, and thermal synthesis. The optimized synthesis conditions allowed to quantify the polyphenols used as reducing agents, such as Trolox and chlorogenic acid. Two chromatographic peaks with different absorption spectrum were monitored during the syntheses. Depending on the molar relationship, a linear relation between the area of the chromatographic peaks and the concentration of the silver or polyphenol was established. For stabilization of silver nanoparticles, different cationic surfactants were used allowing to evaluate the role of anion (chloride and bromide) and of the alkyl chain. The proposed methodology can be used to determine chlorogenic acid up to 3 mM with a detection limit of 34 µM at λ= 400 nm. Chlorogenic acid was determined in dietary products with successful results. Precision (RSD=10%) and recovery (97-100%) were also satisfactory.

Vascular allografts for clinical application in Europe: assessment of 30 years of experience with vascular tissue banking in Brussels.

Vascular tissue banking has been carried out in Brussels for over 30 years in compliance with EU and Swiss tissue banking regulations. A total of 2.765 vascular tissue donations were performed in Belgian, French, Netherlands and Suisse transplant centres: 547(20%), 1.013(37%) and 1.205(43%) during the first, second and third periods, respectively. 85% and 18% increase in donations during the second and third decades compared to previous one, were remarkable. Of the 7.066 evaluated vascular tissues, 2.407(227, 921 and 1.259) were discarded (34.1%), whereas 4.659(523, 1.861 and 2.275) accepted (65.9%) during the respective period. Of the 92 donated veins, 44(47.8%) were discarded and 48(52.2%) accepted. Allografts available for clinical application were stored in vapours of liquid nitrogen. A total of 4.636 allografts were delivered and transplanted for cases of infection (58%), critical limb ischaemia (16%) and congenital cardiac surgery (15%). Thirty veins were implanted. The progressive increases in donations of 20%, 37% and 43% and in transplantations of 20.8%, 34.6% and 45% during the first, second and third periods, respectively, were remarkable. Complications were reported after transplantation and these included acute rejection of two femoral arteries one month after transplantation. We conclude that the donation and transplantation of cryopreserved vascular allografts was stable with a progressive increase over time. Allografts were used predominantly for the treatment of infection, limb salvage for critical ischaemia and for neonates and infants with congenital cardiac malformation. Immune related rejection was observed. This should be a subject of future investigation.

Production and Partial Characterization of Bioactive Compounds from Underutilized Marine Bioresources for a Cosmetic Formulation: Cytotoxicity and Bioactivity Evaluation.

Hydrolyzed collagen, glycogen, and hyaluronic acid, obtained through the biotechnological valorization of underutilized marine bioresources, fulfill cosmetic industry requirements for sustainable products produced under circular economy principles. Hydrolyzed collagen was obtained by hydrolyzing blue shark collagen with papain and ultrafiltration. Glycogen was isolated from industrial mussel cooking wastewaters through ultrafiltration, precipitation, and selective polysaccharide separation. Hyaluronic acid was produced by fermentation, purification, and depolymerization. The main objective was to test the feasibility of including these three biomolecules in a cosmetic formulation as bioactive compounds. For this, the in vitro irritant potential of the three ingredients and also that of the cosmetic formulation was assayed according to the Reconstituted Human Epithelium Test method OECD 439. Moreover, an in vitro assessment of the effect of hydrolyzed collagen and hyaluronic acid combinations on mRNA expression and collagen type I synthesis was evaluated in adult human fibroblasts. This study establishes, for the first time, the potential use of particular hydrolyzed collagen and hyaluronic acid combinations as stimulators of collagen I synthesis in fibroblast cultures. Besides, it provide safety information regarding potential use of those biomolecules in the formulation of a cosmetic preparation positively concluding that both, ingredients and cosmetic preparation, resulted not irritant for skin following an international validated reference method.

Classification of Common Food Lipid Sources Regarding Healthiness Using Advanced Lipidomics: A Four-Arm Crossover Study.

Prospective studies have failed to establish a causal relationship between animal fat intake and cardiovascular diseases in humans. Furthermore, the metabolic effects of different dietary sources remain unknown. In this four-arm crossover study, we investigated the impact of consuming cheese, beef, and pork meat on classic and new cardiovascular risk markers (obtained from lipidomics) in the context of a healthy diet. A total of 33 young healthy volunteers (23 women/10 men) were assigned to one out of four test diets in a Latin square design. Each test diet was consumed for 14 days, with a 2-week washout. Participants received a healthy diet plus Gouda- or Goutaler-type cheeses, pork, or beef meats. Before and after each diet, fasting blood samples were withdrawn. A reduction in total cholesterol and an increase in high density lipoprotein particle size were detected after all diets. Only the pork diet upregulated plasma unsaturated fatty acids and downregulated triglycerides species. Improvements in the lipoprotein profile and upregulation of circulating plasmalogen species were also observed after the pork diet. Our study suggests that, within the context of a healthy diet rich in micronutrients and fiber, the consumption of animal products, in particular pork meat, may not induce deleterious effects, and reducing the intake of animal products should not be regarded as a way of reducing cardiovascular risk in young individuals.

Prospective cohort study to evaluate premedication with simethicone and n-acetilcysteine for upper diagnostic gastrointestinal endoscopy.

INTRODUCTION: The use of premedication for upper gastrointestinal endoscopy (UGE) is not widely established in western countries. The primary aim of the study was to compare gastric visibility according to the total visibility score (TVS). The secondary aim was to assess complications, diagnostic yield, endoscopic procedure time, sedation dose and patient satisfaction. METHODS: A single center prospective cohort study was performed of consecutive adults undergoing an UGE in the afternoon working shift. After completing enrolment in the control group, patients were administered 200 mg simethicone and 500 mg N-acetylcysteine diluted in 100 ml of water >15 minutes before the procedure. All procedures were recorded and a single, blinded endoscopist evaluated the TVS after recruitment of both cohorts. Patient satisfaction was evaluated using the Spanish translation of the American Society of Gastrointestinal Endoscopy satisfaction questionnaire. RESULTS: 205 patients were included in the study, 103 females (50.2%) with a median age of 54.8-years (IQR: 41.2-65.2). 104 were enrolled to the control group and 101 to the intervention group. Patients receiving premedication presented a higher rate of adequate (74.3% vs 45.2; difference 95% CI: 16,3-41,9%, p<0.001) and excellent gastric visibility (23.8% vs 7.7%; difference 95% CI: 6,3-25,8%, p=0.002). Propofol dose was similar, although the median procedure time was lower in the group of no intervention [5 (IQR: 4-7) vs 6 minutes (IQR: 5-7); p=0.03]. Procedure related adverse events were similar, except that patient without premedication experienced more nausea episodes. Major and minor endoscopic findings and the satisfaction questionnaire showed no differences between both groups. CONCLUSION: Patients receiving premedication with simethicone and N-acetylcysteine had a better gastric visibility score, without any increase in adverse events or affecting the patients' satisfaction.

Loss of Snord116 alters cortical neuronal activity in mice: a preclinical investigation of Prader-Willi syndrome.

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder that is characterized by metabolic alteration and sleep abnormalities mostly related to rapid eye movement (REM) sleep disturbances. The disease is caused by genomic imprinting defects that are inherited through the paternal line. Among the genes located in the PWS region on chromosome 15 (15q11-q13), small nucleolar RNA 116 (Snord116) has been previously associated with intrusions of REM sleep into wakefulness in humans and mice. Here, we further explore sleep regulation of PWS by reporting a study with PWScrm+/p- mouse line, which carries a paternal deletion of Snord116. We focused our study on both macrostructural electrophysiological components of sleep, distributed among REMs and nonrapid eye movements. Of note, here, we study a novel electroencephalography (EEG) graphoelements of sleep for mouse studies, the well-known spindles. EEG biomarkers are often linked to the functional properties of cortical neurons and can be instrumental in translational studies. Thus, to better understand specific properties, we isolated and characterized the intrinsic activity of cortical neurons using in vitro microelectrode array. Our results confirm that the loss of Snord116 gene in mice influences specific properties of REM sleep, such as theta rhythms and, for the first time, the organization of REM episodes throughout sleep-wake cycles. Moreover, the analysis of sleep spindles present novel specific phenotype in PWS mice, indicating that a new catalog of sleep biomarkers can be informative in preclinical studies of PWS.

Chromosome banding analysis and genomic microarrays are both useful but not equivalent methods for genomic complexity risk stratification in chronic lymphocytic leukemia patients.

Genome complexity has been associated with poor outcome in patients with chronic lymphocytic leukemia (CLL). Previous cooperative studies established five abnormalities as the cut-off that best predicts an adverse evolution by chromosome banding analysis (CBA) and genomic microarrays (GM). However, data comparing risk stratification by both methods are scarce. Herein, we assessed a cohort of 340 untreated CLL patients highly enriched in cases with complex karyotype (CK) (46.5%) with parallel CBA and GM studies. Abnormalities found by both techniques were compared. Prognostic stratification in three risk groups based on genomic complexity (0-2, 3- 4 and ≥5 abnormalities) was also analyzed. No significant differences in the percentage of patients in each group were detected, but only a moderate agreement was observed between methods when focusing on individual cases (κ=0.507; P<0.001). Discordant classification was obtained in 100 patients (29.4%), including 3% classified in opposite risk groups. Most discrepancies were technique-dependent and no greater correlation in the number of abnormalities was achieved when different filtering strategies were applied for GM. Nonetheless, both methods showed a similar concordance index for prediction of time to first treatment (TTFT) (CBA: 0.67 vs. GM: 0.65) and overall survival (CBA: 0.55 vs. GM: 0.57). High complexity maintained its significance in the multivariate analysis for TTFT including TP53 and IGHV status when defined by CBA (hazard ratio [HR] 3.23; P<0.001) and GM (HR 2.74; P<0.001). Our findings suggest that both methods are useful but not equivalent for risk stratification of CLL patients. Validation studies are needed to establish the prognostic value of genome complexity based on GM data in future prospective studies.

Degradation mechanism of 2-fluoropropene by Cl atoms: experimental and theoretical products distribution studies.

The gas-phase reaction products of 2-fluoropropene (2FP) with Cl atoms have been determined for the first time at 298 K and atmospheric pressure using a 1080 L quartz-glass photoreactor coupled with in situ FTIR spectroscopy to monitor reactants and products. Acetyl fluoride and formyl chloride were observed as the main products with yields of (106 ± 10)% and (100 ± 11)%, respectively. Electronic structure calculations of reactants, intermediates, products and transition states on a detailed mechanism of the reaction were performed by DFT procedures (BMK, M06, M062X/D3), as well as accurate composite methods on both the addition and abstraction reaction channels. From the joint experimental and theoretical studies, we concluded that the reaction occurs primarily via addition to the Cα carbon, with a smaller participation of the addition on the Cß carbon, which is not produced directly from the separated reactants but from the CH3CFCH2Cl intermediate radical through a submerged transition state. The abstraction channel occurs at larger energies than the addition ones, and also presents a submerged transition state, with a lower barrier. No products arising from this channel are expected. The proposed mechanism explains also why formaldehyde, predicted as a product by former theoretical studies, is not found among the experimental products. The atmospheric implications of the reaction products are assessed.

Experimental and Theoretical Kinetic Studies of the Ozonolysis of Selected Allyl Sulfides (H2C═CHCH2SR, R = CH3, CH3CH2): The Effect of Nascent OH Radicals.

Rate coefficients of the O3-initiated oxidation of allyl methyl sulfide (H2C═CHCH2SCH3, AMS) and allyl ethyl sulfide (H2C═CHCH2SCH2CH3, AES) were determined at atmospheric conditions by "in situ" FTIR. The relative kinetic experiments were performed using methylcyclohexane (McH) and carbon monoxide (CO) as nascent OH radical scavengers and in the absence of any scavenger, to determine the impact that the formation of OH radicals has on the rate coefficients. In the absence of scavengers, values of kAMS+O3 = (5.23 ± 3.57) × 10-18 and kAES+O3 = (5.76 ± 1.80) × 10-18 cm3 molecule-1 s-1 were obtained. In the presence of the scavengers, however, the rates decreased to kAMS+O3+McH = (3.92 ± 1.92) × 10-18 and kAMS+O3+CO = (2.63 ± 0.47) × 10-18 cm3 molecule-1 s-1 for AMS, and kAES+O3+McH = (4.78 ± 1.38) × 10-18 and kAES+O3+CO = (3.50 ± 0.27) × 10-18 cm3 molecule-1 s-1 for AES. On the basis of these results, we have decided to recommend the values obtained using CO as scavenger as those best representing the rate coefficient for the reactions of O3 with AMS and AES. The reaction mechanism was explored using DFT and post-Hartree-Fock computational methods. It is shown that the barrier for the common cyclization to primary ozonide (-3.7 ± 0.1 kcal mol-1) followed by other reactions, as well as that for the reaction with the sulfur atom (-5.1 ± 0.1 kcal mol-1), is small and quite close, meaning that both reaction paths should contribute significantly to the global reaction rate.

Corneal Confocal Analysis after Scleral Lens Wear in Keratoconus Patients: A Pilot Study.

SIGNIFICANCE: Scleral lenses rely on the scleroconjunctival region without bearing the cornea, which could improve the symptoms and modify the corneal nerve plexus morphology. PURPOSE: This study aimed to evaluate symptoms and changes in corneal nerve plexus morphology and density of Langerhans cells in keratoconus patients with and without intrastromal corneal ring before and after scleral lens wear. METHODS: Sixteen scleral lens wearers with keratoconus were recruited for this short-term experimental pilot study. Subjects were divided into two groups: keratoconus group and intrastromal corneal ring segment group. All subjects were examined in two visits: baseline (before scleral lens wear) and after 6 months of scleral lens wear, after lens removal. The Schirmer I test, the Ocular Surface Disease Index, tear breakup time, and in vivo confocal microscopy were evaluated. RESULTS: The mean age was 42.33 ± 11.27 years. A significant decrease in tear breakup time was found in the total group ( P = .01, Wilcoxon) compared with baseline. Ocular Surface Disease Index score had decreased after 6 months of scleral lens wear in the keratoconus with intrastromal corneal ring segment subgroup ( P = .03, Wilcoxon) and in the total group ( P = .001, Wilcoxon). No statistical changes in nerve density, tortuosity, and ramification were found for either the total group or the subgroup. However, the mean nerve length was higher in all groups, especially in the keratoconus subgroup ( P = .03, Wilcoxon) after 6 months of scleral lens wear. Regarding optical density, the total group showed a significant increase after 6 months of wearing ( P = .02, Wilcoxon). Finally, Langerhans cell density was not statistically different in any group. CONCLUSIONS: These results suggest that scleral lens wearing improves the symptoms and increased the mean length nerves after 6 months of wear use in keratoconus patients.

Multicentric infantile myofibromatosis with extensive involvement limited to bone.

Infantile myofibromatosis (IM) is the most common benign fibrous tumor of infancy, characterized by the development of single or multiple nodules in the skin, soft tissues, bone, and/or viscera. Multicentric forms are less frequent and can affect different tissues simultaneously and their prognosis depends on their extension and visceral involvement. Rarely, these forms are limited to the skeleton, in which case the absence of extraosseous lesions makes it difficult to suspect this entity. We present the case of an infant with multiple radiolucent lesions involving the skull, ribs, spine, and long bones, discovered in a radiological study performed after a minor trauma. A broad differential diagnosis was considered based on the osteolytic and polyostotic nature of the lesions on imaging studies. This report details and illustrates the typical radiological findings in bony involvement of IM, which suggest this disorder over other diagnostic options.

Antibiotic Prescribing Patterns for Pediatric Urgent Care Clinicians.

OBJECTIVE: Previous studies have reported high rates of inappropriate antibiotic prescriptions in urgent care (UC). Specific prescribing patterns for the most common diagnoses are not known. The aim of the study is to determine the diagnoses for which antibiotics are prescribed in pediatric UC settings. METHODS: We recruited pediatric UC providers via email to participate in a national multisite quality improvement study. Participants completed a survey on 10 consecutive encounters in which an antibiotic was given between March and May 2018. Encounters in which only topical antibiotics were prescribed were excluded. We categorized the encounters into 3 previously established tiers to determine appropriateness of antibiotic use. The tiers represent a descending order for antibiotic need based on diagnoses, with the first tier representing diagnoses almost always requiring antibiotics and the third tier representing diagnoses when an antibiotic is almost never required. We reported the diagnoses and frequency of antibiotic prescription within each tier. RESULTS: The 157 providers from 20 institutions submitted a total of 2809 encounters. We excluded 339 encounters in which only topical antibiotics were prescribed. Most diagnoses fell into the tier 2 category (85.81%), with only 9.12% in tier 1 and 5.06% in tier 3. The most common diagnoses reported were acute otitis media (48.96%), pharyngitis (25.09%), and skin and soft tissue infections (7.29%). CONCLUSIONS: In this sample of pediatric UC encounters, only 5% of diagnoses receiving antibiotic prescriptions were made up of tier 3 diagnoses, determined to almost never require antibiotics. While viral respiratory infections have been reported to frequently be treated with antibiotics in general UC centers, our study of pediatric UC centers showed that this was infrequent. However, otitis media with effusion and otalgia should be further investigated. With most antibiotic prescriptions being tier 2 diagnoses, pediatric UC providers can use evidence-based prescribing practices, shared decision making, and contingency plans to reduce unnecessary antibiotic exposure.