Synapse-Specific Trapping of SNARE Machinery Proteins in the Anesthetized Drosophila Brain.

General anesthetics disrupt brain network dynamics through multiple pathways, in part through postsynaptic potentiation of inhibitory ion channels as well as presynaptic inhibition of neuroexocytosis. Common clinical general anesthetic drugs, such as propofol and isoflurane, have been shown to interact and interfere with core components of the exocytic release machinery to cause impaired neurotransmitter release. Recent studies however suggest that these drugs do not affect all synapse subtypes equally. We investigated the role of the presynaptic release machinery in multiple neurotransmitter systems under isoflurane general anesthesia in the adult female Drosophila brain using live-cell super-resolution microscopy and optogenetic readouts of exocytosis and neural excitability. We activated neurotransmitter-specific mushroom body output neurons and imaged presynaptic function under isoflurane anesthesia. We found that isoflurane impaired synaptic release and presynaptic protein dynamics in excitatory cholinergic synapses. In contrast, isoflurane had little to no effect on inhibitory GABAergic or glutamatergic synapses. These results present a distinct inhibitory mechanism for general anesthesia, whereby neuroexocytosis is selectively impaired at excitatory synapses, while inhibitory synapses remain functional. This suggests a presynaptic inhibitory mechanism that complements the other inhibitory effects of these drugs.

Mental health status, not resilience, influences functional recovery after arthroscopic rotator cuff repairs.

BACKGROUND: Recent literature has shown the importance of patient psychosocial status in overcoming stressful events, such as surgery. Resilience, the ability to "bounce back" from adversity, has been recently correlated to outcomes following arthroscopic rotator cuff repair (RCR). Overall mental well-being has also been shown to be important because patients with clinical depression and anxiety may have worse outcomes. Substantial clinical benefit (SCB) is the threshold of outcome improvement that a patient perceives as considerable. The purpose of this study was to assess the influence of preoperative resilience, mental health status, and rotator cuff tear size on patient outcome recovery measured by the American Shoulder and Elbow Surgeons (ASES) score. METHODS: Patients undergoing arthroscopic RCR performed from 2016 through 2019 at a single tertiary institution by fellowship-trained sports surgeons with a high-volume shoulder practice were included. The Brief Resilience Scale (BRS) score and Veterans RAND 12-Item Health Survey (VR-12) Mental Component Score (MCS) were collected preoperatively. ASES scores were obtained preoperatively, as well as 6 and 12 months postoperatively. Patients were divided into 2 groups based on the SCB threshold of 87 for the ASES score based on validated, established literature. Rotator cuff tear size was classified as small (≤3 cm) or large (>3 cm). VR-12 MCS, BRS, and ASES scores were compared at baseline, 6 months, and 1 year using separate mixed-model analyses of variance between the tear size and SCB groups. For ASES score comparison, the VR-12 MCS was used as a covariate to account for differences in baseline mental status. RESULTS: RCR was performed in 119 patients, with an average age of 61 years (standard deviation, 10 years). There were 71 male and 48 female patients. At 6 months, 43% of patients met the SCB threshold. The VR-12 MCS was significantly different between RCR patients who met the SCB threshold for the ASES score and those who did not at 6 and 12 months for large rotator cuff tears (P = .001) but not small tears (P = .07). The BRS score was not different between the tear size and SCB groups at any time point (P = .12). CONCLUSION: Our results show that patients who met the SCB threshold at 6 months postoperatively after arthroscopic RCR demonstrated higher preoperative VR-12 MCS values; however, higher preoperative BRS scores were not seen in those meeting the SCB threshold. In fact, when baseline VR-12 MCS values were accounted for in patients with large rotator cuff tears, the differences in ASES scores normalized. This finding suggests that baseline mental health status, as measured by the VR-12 MCS, significantly influenced patients' functional recovery following RCR. Future research should focus on preoperative psychosocial well-being to optimize postoperative outcomes.

Investigation and Mitigation of Noise Contributions in a Compact Heterodyne Interferometer.

We present a noise estimation and subtraction algorithm capable of increasing the sensitivity of heterodyne laser interferometers by one order of magnitude. The heterodyne interferometer is specially designed for dynamic measurements of a test mass in the application of sub-Hz inertial sensing. A noise floor of 3.31×10-11m/Hz at 100 mHz is achieved after applying our noise subtraction algorithm to a benchtop prototype interferometer that showed a noise level of 2.76×10-10m/Hz at 100 mHz when tested in vacuum at levels of 3×10-5 Torr. Based on the previous results, we investigated noise estimation and subtraction techniques of non-linear optical pathlength noise, laser frequency noise, and temperature fluctuations in heterodyne laser interferometers. For each noise source, we identified its contribution and removed it from the measurement by linear fitting or a spectral analysis algorithm. The noise correction algorithm we present in this article can be generally applied to heterodyne laser interferometers.

Optomechanical lasers for inertial sensing.

We have developed an inertially sensitive optomechanical laser by combining a vertical-external-cavity surface-emitting laser (VECSEL) with a monolithic fused silica resonator. By placing the external cavity mirror of the VECSEL onto the optomechanical resonator test mass, we create a sensor where external accelerations are directly transcribed onto the lasing frequency. We developed a proof-of-principle laboratory prototype and observe test mass oscillations at the resonance frequency of the sensor through the VECSEL lasing frequency, 4.18±0.03Hz. In addition, we set up an ancillary heterodyne interferometer to track the motion of the mechanical oscillator's test mass, observing a resonance of 4.194±0.004Hz. The interferometer measurements validate the VECSEL results, confirming the feasibility of using optomechanical lasers for inertial sensing.

Quantum hybrid optomechanical inertial sensing.

We discuss the design of quantum hybrid inertial sensor that combines an optomechanical inertial sensor with the retroreflector of a cold atom interferometer. This sensor fusion approach provides absolute and high-accuracy measurements with cold atom interferometers, while utilizing the optomechanical inertial sensor at frequencies above the repetition rate of the atom interferometer. This improves the overall measurement bandwidth as well as the robustness and field deployment capabilities of these systems. We evaluate which parameters yield an optimal acceleration sensitivity, from which we anticipate a noise floor at nano-g levels from DC to 1 kHz.

Optomechanical inertial sensors.

We present a performance analysis of compact monolithic optomechanical inertial sensors that describes their key fundamental limits and overall acceleration noise floor. Performance simulations for low-frequency gravity-sensitive inertial sensors show attainable acceleration noise floors on the order of 1×10-11m/s2Hz. Furthermore, from our performance models, we devised an optimization approach for our sensor designs, sensitivity, and bandwidth trade space. We conducted characterization measurements of these compact mechanical resonators, demonstrating mQ-products at levels of 250 kg, which highlight their exquisite acceleration sensitivity.

A Comparison of Pavlik Harness Treatment Regimens for Dislocated But Reducible (Ortolani+) Hips in Infantile Developmental Dysplasia of the Hip.

BACKGROUND: Variation exists in the Pavlik harness (PH) treatment regimen for infantile developmental dysplasia of the hip (DDH). The purpose of this study was to determine if the daily PH wear duration (23 vs. 24 h) and frequency of follow-up visits affect the clinical and radiographic outcomes of infants with dislocated but reducible (Ortolani+) hips. METHODS: This study reviewed prospectively enrolled patients with DDH in a single center who presented at age <6 months with Ortolani+ hips and were treated with PH. Recommended daily PH wear duration (23 vs. 24 h) and the frequency of clinic visits in first 4 weeks after the initiation of PH treatment were analyzed. The clinical success (stable hip that did not require closed or open reduction or the use of an abduction orthosis) and radiographic success based on the acetabular index at 2-year follow-up were compared between different PH regimen groups. RESULTS: Sixty-two patients (74 hips, 53 females) with Ortolani+ hips had a mean age of presentation of 23±28 days (range, 4 to 128 d) and mean follow-up of 33.2±18.4 months (range, 8 to 85 mo). Overall clinical success rate of PH for Ortolani+ hips was 93% (69/74 hips) and radiographic success rate at 2 years was 84% (48/57 hips). There was no difference in clinical or radiographic success rate between the 23- and 24-hour wear groups (P>0.99, 0.73) or between hips assessed almost weekly compared with once or twice during the first 4 weeks of PH treatment (P>0.99 for both). CONCLUSIONS: The 23- versus 24-hour PH regimen and frequency of clinic visits in the first 4 weeks of PH treatment did not affect the clinical or radiographic success rate of Ortolani+ hips in infantile DDH. A strict weekly clinic visit and 24-hour PH regimen may not be necessary to obtain stable reduced hips in infants presenting <6 months of age with Ortolani+ hips. LEVEL OF EVIDENCE: Level III-therapeutic.

Meningioma and psychiatric symptoms: A case report and brief review.

BACKGROUND: Atypical presentation of psychiatric symptoms can lead to a variety of misdiagnoses. Organic causes, including brain tumors, should be considered under these circumstances. METHODS: We present a case report of an 84-year-old woman with irritable, aggressive, and delusional behavior. Her earlier diagnoses included altered mental status, encephalopathy, dementia, nonspecified psychosis, and delirium with delusions. We suspected that a brain tumor could be causing her psychiatric symptoms. RESULTS: CT of the head revealed 2 calcified meningiomas, which did not require surgery. Neuropsychological testing results were consistent with frontal lesion type of cognitive and psychotic symptoms. Psychiatric symptoms improved with risperidone. A brief review of the literature is included. CONCLUSIONS: Brain imaging should be considered in cases of atypical psychiatric presentations. Past medical records and neuropsychological testing could assist in the diagnosis.

Haemophagocytic lymphohistiocytosis following COVID-19 mRNA vaccination.

The development of vaccinations has been instrumental in the ongoing effort to combat the COVID-19 pandemic. Although the benefits of vaccination are unquestionable, there have been reports of potentially rare life-threatening complications following vaccination including thrombocytopaenia, haemolytic anaemia, vasculitis and myocarditis. Haemophagocytic lymphohistiocytosis (HLH), a rare but life-threatening inflammatory condition, has also been described postadenoviral vector COVID-19 vaccination but it has never been reported post-messenger RNA (mRNA) COVID-19 vaccination. We report two cases of HLH admitted to our hospital after administration of COVID-19 mRNA vaccines. We also searched the vaccine adverse event reporting system and found 50 reports of suspected HLH following COVID-19 vaccination. Presently, we cannot define a causality between COVID-19 mRNA vaccination and HLH development. However, we hope the reporting of our two cases (and additional cases seen in the adverse event reporting database) will help us determine whether there is a potential relationship. Prompt recognition of this condition is of utmost importance to initiate life-saving therapy.

Metabolomics reveals target and off-target toxicities of a model organophosphate pesticide to roach (Rutilus rutilus): implications for biomonitoring.

The ability of targeted and nontargeted metabolomics to discover chronic ecotoxicological effects is largely unexplored. Fenitrothion, an organophosphate pesticide, is categorized as a "red list" pollutant, being particularly hazardous to aquatic life. It acts primarily as a cholinesterase inhibitor, but evidence suggests it can also act as an androgen receptor antagonist. Whole-organism fenitrothion-induced toxicity is well-established, but information regarding target and off-target molecular toxicities is limited. Here we study the molecular responses of male roach ( Rutilus rutilus ) exposed to fenitrothion, including environmentally realistic concentrations, for 28 days. Acetylcholine was assessed in brain; steroid metabolism was measured in testes and plasma; and NMR and mass spectrometry-based metabolomics were conducted on testes and liver to discover off-target toxicity. O-demethylation was confirmed as a major route of pesticide degradation. Fenitrothion significantly depleted acetylcholine, confirming its primary mode of action, and 11-ketotestosterone in plasma and cortisone in testes, showing disruption of steroid metabolism. Metabolomics revealed significant perturbations to the hepatic phosphagen system and previously undocumented effects on phenylalanine metabolism in liver and testes. On the basis of several unexpected molecular responses that were opposite to the anticipated acute toxicity, we propose that chronic pesticide exposure induces an adapting phenotype in roach, which may have considerable implications for interpreting molecular biomarker responses in field-sampled fish.

Tracking Single Molecule Dynamics in the Adult Drosophila Brain.

Super-resolution microscopy provides valuable insight for understanding the nanoscale organization within living tissue, although this method is typically restricted to cultured or dissociated cells. Here, we develop a method to track the mobility of individual proteins in ex vivo adult Drosophila melanogaster brains, focusing on a key component of the presynaptic release machinery, syntaxin1A (Sx1a). We show that individual Sx1a dynamics can be reliably tracked within neurons in the whole fly brain, and that the mobility of Sx1a molecules increases following conditional neural stimulation. We then apply this preparation to the problem of general anesthesia, to address how different anesthetics might affect single molecule dynamics in intact brain synapses. We find that propofol, etomidate, and isoflurane significantly impair Sx1a mobility, while ketamine and sevoflurane have little effect. Resolving single molecule dynamics in intact fly brains provides a novel approach to link localized molecular effects with systems-level phenomena such as general anesthesia.

COVID-19 infection presenting as paroxysmal nocturnal hemoglobinuria.

A diagnosis of paroxysmal nocturnal hemoglobinuria (PNH) was elicited during acute COVID-19 infection. COVID-19 spike proteins trigger the alternative pathway of complement. Acute SARS-CoV-2 infection possibly expanded an existing PIG-A mutation.

Immune thrombocytopenic purpura and acute liver injury after COVID-19 vaccine.

A 26-year-old woman was sent to the emergency room by her primary care physician for a new petechial rash and thrombocytopenia 2 weeks after receiving the Moderna mRNA-1273 SARS-CoV-2 vaccine. Her hospital course was complicated by transaminitis. Her platelet count improved to normal on hospital day 5 after receiving intravenous steroids and intravenous immunoglobulin to treat her suspected diagnosis of immune thrombocytopenic purpura. Extensive workup for her thrombocytopenia and transaminitis was unremarkable including ruling out infectious, autoimmune and toxic causes. A liver biopsy was unrevealing and her transaminitis was improved on discharge. Although not proven, the temporal relationship of her vaccination with thrombocytopenia and abnormal liver enzymes points towards the Moderna mRNA-1273 SARS-CoV-2 vaccine as the most likely inciting factor.

Modeling the metabolic profile of Mytilus edulis reveals molecular signatures linked to gonadal development, sex and environmental site.

The monitoring of anthropogenic chemicals in the aquatic environment including their potential effects on aquatic organisms, is important for protecting life under water, a key sustainable development goal. In parallel with monitoring the concentrations of chemicals of concern, sentinel species are often used to investigate the biological effects of contaminants. Among these, bivalve molluscs such as mussels are filter-feeding and sessile, hence an excellent model system for measuring localized pollution. This study investigates the relationship between the metabolic state of the blue mussel (Mytilus edulis) and its physiology in different environments. We developed a computational model based on a reference site (relatively unpolluted) and integrated seasonal dynamics of metabolite relative concentrations with key physiological indicators and environmental parameters. The analysis of the model revealed that changes in metabolite levels during an annual cycle are influenced by water temperature and are linked to gonadal development. This work supports the importance of data-driven biology and its potential in environmental monitoring.

Treatment with Granulocyte-colony Stimulating Factor (G-CSF) is not associated with Increased Risk of Brain Metastasis in Patients with De Novo Stage IV Breast Cancer.

Background: Survival outcome after developing brain metastasis is poor and there is an unmet need to identify factors that can promote brain metastasis. Granulocyte-colony stimulating factor (G-CSF) is given to support neutrophil recovery after myelosuppressive chemotherapy to some patients. However, there is emerging evidence that neutrophils can promote metastasis, including through the formation of neutrophil extracellular traps (NETs), scaffolds of chromatin with enzymes expelled from neutrophils to the extracellular space. In animal models, G-CSFs can induce NETs to promote liver and lung metastasis. The primary objective of this study was to test the association between G-CSF use and the later incidence of brain metastasis. Methods: Patients with de novo Stage IV breast cancer, without known brain metastasis at the time of initial diagnosis, were identified from electronic medical records covering the period from 1/1/2013 to 12/31/2020 at Northwell Health. Univariate and multivariate logistic regression models were used to test the association between variables of interest, including G-CSF use, and brain metastasis. Results: A total of 78 patients were included in the final analysis. Among those 78 patients, 24 patients (30.8%) had received G-CSF along with chemotherapy at least once. In logistic regression models, G-CSF use was not a significant factor to predict brain metastasis (OR 1.89 [95%CI 1.89-5.33]; P=0.23). Interestingly, in multivariate logistic models, pulmonary embolism (PE)/deep venous thrombosis (DVT) was a significant predictive factor of brain metastasis (OR 6.74 [95%CI 1.82-25.01]; P=0.004) (38.5% vs 21.5%). Conclusions: The use of G-CSF was not associated with increased risk of brain metastasis in patients with de novo Stage IV breast cancer. Interestingly, PE/DVT, which can be associated with elevated NETs, was associated with brain metastasis. Further studies are warranted to determine whether DVT/PE with or without elevated NETs levels in the blood, is predictive of developing brain metastasis in patients with de novo Stage IV breast cancer.

Pharmacological activation of IKr in models of long QT Type 2 risks overcorrection of repolarization.

AIMS: Current treatment for congenital long QT syndrome Type 2 (cLQTS2), an electrical disorder that increases the risk of life-threatening cardiac arrhythmias, is aimed at reducing the incidence of arrhythmia triggers (beta-blockers) or terminating the arrhythmia after onset (implantable cardioverter-defibrillator). An alternative strategy is to target the underlying disease mechanism, which is reduced rapid delayed rectifier current (IKr) passed by Kv11.1 channels. Small molecule activators of Kv11.1 have been identified but the extent to which these can restore normal cardiac signalling in cLQTS2 backgrounds remains unclear. Here, we examined the ability of ICA-105574, an activator of Kv11.1 that impairs transition to the inactivated state, to restore function to heterozygous Kv11.1 channels containing either inactivation enhanced (T618S, N633S) or expression deficient (A422T) mutations. METHODS AND RESULTS: ICA-105574 effectively restored Kv11.1 current from heterozygous inactivation enhanced or expression defective mutant channels in heterologous expression systems. In a human-induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) model of cLQTS2 containing the expression defective Kv11.1 mutant A422T, cardiac repolarization, estimated from the duration of calcium transients in isolated cells and the rate corrected field potential duration (FPDc) in culture monolayers of cells, was significantly prolonged. The Kv11.1 activator ICA-105574 was able to reverse the prolonged repolarization in a concentration-dependent manner. However, at higher doses, ICA-105574 produced a shortening of the FPDc compared to controls. In vitro and in silico analysis suggests that this overcorrection occurs as a result of a temporal redistribution of the peak IKr to much earlier in the plateau phase of the action potential, which results in early repolarization. CONCLUSION: Kv11.1 activators, which target the primary disease mechanism, provide a possible treatment option for cLQTS2, with the caveat that there may be a risk of overcorrection that could itself be pro-arrhythmic.

Rare presentation of granulomatosis with polyangiitis.

A 62-year-old man with no pertinent medical history presented with lower extremity weakness and worsening distal fingertips and toe cyanosis/gangrene. In the outpatient setting, he was initially being treated for Raynaud's phenomenon with a calcium channel blocker. On presentation, the patient had elevated inflammatory markers and white blood cell count. Serum vasculitis panel (proteinase-3 antibody) supported the diagnosis of granulomatosis with polyangiitis. His hospital course was complicated by ischaemic stroke and a diagnosis of mononeuritis multiplex in his lower extremities. After initiating therapy with intravenous steroid and rituximab, his symptoms overall improved including cyanotic fingertips/toes. His inflammatory markers and leucocytosis also improved. Outpatient follow-up consisted of further rituximab infusions and unrelated umbilical hernia incarceration which required surgery. He was found incidentally to have subsegmental pulmonary emboli which most likely occurred during the initial presentation prior to his diagnosis. The patient moved out of state and was lost to follow-up.

Comparison of Pavlik Harness treatment regimens for reduced but dislocatable (Barlow positive) hips in infantile DDH.

OBJECTIVE: Although the Pavlik Harness (PH) is the most utilized treatment for developmental dysplasia of the hip (DDH), the ideal treatment protocol (frequency of clinic visits in the first month and daily wear duration) for Barlow â€‹+ â€‹hips (reduced but dislocatable) has yet to be defined. METHODS: This study compared DDH patients with Barlow hips who were treated with 23 vs 24 h per day PH wear and weekly vs every other week visits. Clinical success was defined as a stable hip that did not require closed or open reduction, or the use of an abduction orthosis prior to achieving clinical stability. Radiographic success was based on the acetabular index at 2-year follow up. RESULTS: Sixty-five patients (75 hips/58 females) with Barlow hips had a mean age of presentation of 15 ±â€¯12 days (range 4-70) and mean follow-up of 33 ±â€¯17 months (range 6-90). There was no difference in clinical or radiographic success rate between 23 h vs 24 h wear groups (p > 0.99 both) or the Frequently vs Infrequent visit groups (p = 0.49 both). Overall clinical success rate was 97% (73/75 hips) and radiographic success rate at 2 years was 97% (58/60 hips). CONCLUSION: A strict, weekly clinic visit and 24-h PH regimen may not be necessary to obtain good clinical and radiographic outcomes in infants presenting <6 months of age with Barlow positive hips. LEVEL OF EVIDENCE: Therapeutic, Level III.

Prospective Evaluation of Range of Motion in Acute ACL Reconstruction Using Patellar Tendon Autograft.

BACKGROUND: Optimal timing of anterior cruciate ligament (ACL) reconstruction has been a topic of controversy. Reconstruction has historically been delayed for at least 3 weeks, given previous studies reporting a high risk of postoperative arthrofibrosis and suboptimal clinical results. PURPOSE: To prospectively evaluate postoperative range of motion following acutely reconstructed ACLs with patellar tendon autograft. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients (age >18 years) who had ACL reconstruction as soon as possible after injury, regardless of the condition or preoperative range of motion of the injured knee, underwent reconstruction with patellar tendon autograft. An identical standard surgical technique and postoperative rehabilitation were employed for all patients. Postoperative assessment included active range of motion measurements with a goniometer. Subjective outcomes were assessed with the Knee injury and Osteoarthritis Outcome Score (KOOS). RESULTS: A total of 25 consecutive patients who met the inclusion criteria were enrolled. The mean age was 27.9 years (range, 20-48 years), and 19 were men. The time from injury to surgery was a mean 4.5 days (range, 1-9 days). The mean objective follow-up was 10.9 months (range, 3 days-19.4 months), and range of motion was regained at a mean 4.4 months (range, 1-9 months). Three meniscal repairs and 3 microfractures were performed concomitantly. There was 1 graft failure at 3 years postoperatively, noted at 50 months of subjective follow-up. There was no loss of extension >3° as compared with the contralateral knee in any patient. There was no loss of flexion >5° as compared with the contralateral knee in any patient who completed objective follow-up. The mean KOOS at final subjective follow-up was 82.8 (range, 57.7-98.8) at a mean 56.6 months postoperative (n = 14/24; range, 48-58 months). CONCLUSION: Excellent clinical results can be achieved following ACL reconstruction performed ≤9 days after injury with patellar tendon autograft. The authors found that early ACL reconstructions do not result in loss of motion or suboptimal clinical results as long as a rehabilitation protocol emphasizing extension and early range of motion is employed.