Wireless Stimulation of Antennal Muscles in Freely Flying Hawkmoths Leads to Flight Path Changes

Insect antennae are sensory organs involved in a variety of behaviors, sensing many different stimulus modalities. As mechanosensors, they are crucial for flight control in the hawkmoth Manduca sexta. One of their roles is to mediate compensatory reflexes of the abdomen in response to rotations of the body in the pitch axis. Abdominal motions, in turn, are a component of the steering mechanism for flying insects. Using a radio controlled, programmable, miniature stimulator, we show that ultra-low-current electrical stimulation of antennal muscles in freely-flying hawkmoths leads to repeatable, transient changes in the animals' pitch angle, as well as less predictable changes in flight speed and flight altitude. We postulate that by deflecting the antennae we indirectly stimulate mechanoreceptors at the base, which drive compensatory reflexes leading to changes in pitch attitude.United States. Defense Advanced Research Projects Agenc

Relative stereociliary motion in a hair bundle opposes amplification at distortion frequencies

Direct gating of mechanoelectrical-transduction channels by mechanical force is a basic feature of hair cells that assures fast transduction and underpins the mechanical amplification of acoustic inputs. But the associated nonlinearity - the gating compliance - inevitably distorts signals. Because reducing distortion would make the ear a better detector, we sought mechanisms with that effect. Mimicking in vivo stimulation, we used stiff probes to displace individual hair bundles at physiological amplitudes and measured the coherence and phase of the relative stereociliary motions with a dual-beam differential interferometer. Although stereocilia moved coherently and in phase at the stimulus frequencies, large phase lags at the frequencies of the internally generated distortion products indicated dissipative relative motions. Tip links engaged these relative modes and decreased the coherence in both stimulated and free hair bundles. These results show that a hair bundle breaks into a highly dissipative serial arrangement of stereocilia at distortion frequencies, precluding their amplification.Comment: 33 pages in total, including the main article with one table and three figures, as well as the supplemental information that itself contains two figure

Capnocytophaga Keratitis: Clinical Presentation and Use of Metagenomic Deep Sequencing for Diagnosis.

PurposeTo report our experience with 2 cases of Capnocytophaga keratitis.MethodsThis is a retrospective study of case reports. We present the clinical presentation, diagnosis, and treatment strategies of 2 patients who presented with Capnocytophaga keratitis.ResultsBoth patients had risk factors including systemic immune compromise and ocular trauma. Both patients had robust inflammatory keratitis with necrosis. Case 1 demonstrates identification of Capnocytophaga with traditional microbiologic techniques. Case 2 demonstrates the use of unbiased metagenomic deep sequencing for identification of this unusual corneal pathogen.ConclusionsCapnocytophaga is a rare and aggressive infection. Even when traditional culture identifies the pathogen rapidly, keratitis can progress to perforation. In cases of severe keratitis in which traditional culture methods are unrevealing, metagenomic deep sequencing has potential to provide actionable diagnoses

Capnocytophaga Keratitis: Clinical Presentation and Use of Metagenomic Deep Sequencing for Diagnosis.

PurposeTo report our experience with 2 cases of Capnocytophaga keratitis.MethodsThis is a retrospective study of case reports. We present the clinical presentation, diagnosis, and treatment strategies of 2 patients who presented with Capnocytophaga keratitis.ResultsBoth patients had risk factors including systemic immune compromise and ocular trauma. Both patients had robust inflammatory keratitis with necrosis. Case 1 demonstrates identification of Capnocytophaga with traditional microbiologic techniques. Case 2 demonstrates the use of unbiased metagenomic deep sequencing for identification of this unusual corneal pathogen.ConclusionsCapnocytophaga is a rare and aggressive infection. Even when traditional culture identifies the pathogen rapidly, keratitis can progress to perforation. In cases of severe keratitis in which traditional culture methods are unrevealing, metagenomic deep sequencing has potential to provide actionable diagnoses

Peripheral Blood Transcriptome in Patients with Sarcoidosis-Associated Uveitis

PurposeTo identify peripheral blood transcriptome differences in uveitis patients with sarcoidosis compared to those with Vogt-Koyanagi-Harada (VKH) syndrome and controls.MethodsTen patients with uveitis compatible with sarcoidosis (eight with pulmonary sarcoidosis, one with central nervous system sarcoidosis, and one with conjunctival sarcoidosis), nine patients with VKH, and nine healthy controls were prospectively enrolled.ResultsTen genes exhibited a four-fold difference in expression in sarcoidosis patients compared to controls, many being involved in regulating inflammatory processes or cellular responses to microbes.ConclusionsThis research suggests that the transcriptome in sarcoidosis is robust enough to be detected in the peripheral blood and that sarcoidosis can be distinguished from healthy controls. Differentially expressed genes may serve as candidates warranting further investigation with respect to disease pathophysiology and may provide additional information, such as ability to stratify patients based on associated disease severity and anatomical location of inflammation within the eye

Metagenomic Deep Sequencing to Investigate for an Infectious Etiology of Iridocorneal Endothelial Syndrome.

PurposeIridocorneal endothelial (ICE) syndrome is a group of rare ocular conditions that result from abnormal corneal endothelial cells, leading to secondary glaucoma, iris distortions, and corneal edema. The etiology of ICE is unknown, although it has been associated with viral infections, such as herpes simplex virus. In this study, we sought to identify an infectious etiology for ICE using advanced molecular techniques.MethodsMetagenomic RNA sequencing (MDS) is a high-throughput sequencing approach that can identify all pathogens in any clinical sample, including RNA viruses. Descemet membrane and aqueous fluid from patients with ICE syndrome were subjected to MDS testing.ResultsSamples from 3 patients with ICE were analyzed. MDS was performed on the aqueous fluid of 3 patients and Descemet membrane and endothelial cell tissue from 1 patient. Viral pathogens were not identified in any of the samples.ConclusionsWe were unable to identify a viral etiology in the tissues of patients with the Chandler variant of ICE syndrome, although this study was limited by sample size

Metagenomic Deep Sequencing to Investigate for an Infectious Etiology of Iridocorneal Endothelial Syndrome.

PurposeIridocorneal endothelial (ICE) syndrome is a group of rare ocular conditions that result from abnormal corneal endothelial cells, leading to secondary glaucoma, iris distortions, and corneal edema. The etiology of ICE is unknown, although it has been associated with viral infections, such as herpes simplex virus. In this study, we sought to identify an infectious etiology for ICE using advanced molecular techniques.MethodsMetagenomic RNA sequencing (MDS) is a high-throughput sequencing approach that can identify all pathogens in any clinical sample, including RNA viruses. Descemet membrane and aqueous fluid from patients with ICE syndrome were subjected to MDS testing.ResultsSamples from 3 patients with ICE were analyzed. MDS was performed on the aqueous fluid of 3 patients and Descemet membrane and endothelial cell tissue from 1 patient. Viral pathogens were not identified in any of the samples.ConclusionsWe were unable to identify a viral etiology in the tissues of patients with the Chandler variant of ICE syndrome, although this study was limited by sample size

Reduction of Coronavirus Burden With Mass Azithromycin Distribution.

We evaluated the potential antiviral effects of azithromycin on the nasopharyngeal virome of Nigerien children who had received multiple rounds of mass drug administration. We found that the respiratory burden of non-severe acute respiratory syndrome coronaviruses was decreased with azithromycin distributions. Clinical Trials Registration. NCT02047981

Effect of Azithromycin on the Ocular Surface Microbiome of Children in a High Prevalence Trachoma Area.

PURPOSE: The aim of this study was to evaluate the effect of the 4 times per year mass azithromycin distributions on the ocular surface microbiome of children in a trachoma endemic area. METHODS: In this cluster-randomized controlled trial, children aged 1 to 10 years in rural communities in the Goncha Seso Enesie district of Ethiopia were randomized to either no treatment or treatment with a single dose of oral azithromycin (height-based dosing to approximate 20 mg/kg) every 3 months for 1 year. Post hoc analysis of ocular surface Chlamydia trachomatis load, microbial community diversity, and macrolide resistance determinants was performed to evaluate differences between treatment arms. RESULTS: One thousand two hundred fifty-five children from 24 communities were included in the study. The mean azithromycin coverage in the treated communities was 80% (95% CI: 73%-86%). The average age was 5 years (95% CI: 4-5). Ocular surface C. trachomatis load was reduced in children treated with the 4 times per year azithromycin ( P = 0.0003). Neisseria gonorrhoeae , Neisseria lactamica , and Neisseria meningitidis were more abundant in the no-treatment arm compared with the treated arm. The macrolide resistance gene ermB was not different between arms ( P = 0.63), but mefA / E was increased ( P = 0.04) in the azithromycin-treated arm. CONCLUSIONS: We found a reduction in the load of C. trachomatis and 3 Neisseria species in communities treated with azithromycin. These benefits came at the cost of selection for macrolide resistance