Citations

AbstractBackgroundFlow cytometry protocols for counting fresh CD34+ cell samples are not ideal for cryopreserved products due to cryoprotectant cytotoxicity. For cryopreserved samples, often large volumes of hypotonic solutions, which can cause cell death, are used to remove the cryoprotectant with a post‐thaw wash. We recently developed a novel multistep dilution method with subsequent flow cytometry analysis to allow for accurate and reproducible results. The previous method involved washing steps which invalidate the ability to enumerate cell recovery, and success had to be gauged solely on viability. The new method allows for assessment of total cell recovery and viable cell recovery.Study Design and MethodsApheresis products were cryopreserved in 10% DMSO at a target WBC concentration of 300 × 106/mL. Cryovials from these products were thawed at 37°C, and samples were diluted 1:2 by three additions of 1/3 sample volume using 1%‐Human Albumin in Dextran 40 (10% Low Molecular Weight Dextran in 0.9% NaCl) separated by 5 min between each addition. A 1:10 dilution was performed to obtain the correct cell concentration for flow cytometric analysis resulting in a 1:20 dilution. End WBC concentrations were ~15 × 106/mL with DMSO diluted to 0.5%.ResultsFifty‐two samples were tested with this new method. Total and viable cell recoveries were calculated based on pre‐cryopreservation data. Median total cell recoveries for CD34 and CD3 were >85%, while median viable cell recoveries were >75%.DiscussionCryopreserved samples can be reliably prepared for flow cytometric testing using a step‐wise dilution to preserve cell integrity and robust recoveries.

BACKGROUND While most hypertriglyceridemia is asymptomatic, hypertriglyceridemia-associated acute pancreatitis (HTG-AP) can be more severe than AP of other etiologies. The reasons underlying this are unclear. We thus examined whether lipolytic generation of nonesterified fatty acids (NEFAs) from circulating triglycerides (TGs) could worsen clinical outcomes. METHODS Admission serum TGs, NEFA composition, and concentrations were analyzed prospectively for 269 patients with AP. These parameters, demographics, and clinical outcomes were compared between HTG-AP (TGs >500 mg/dL; American Heart Association [AHA] 2018 guidelines) and AP of other etiologies. Serum NEFAs were correlated with serum TG fatty acids (TGFAs) alone and with the product of TGFA serum lipase (NEFAs – TGFAs × lipase). Studies in mice and rats were conducted to understand the role of HTG lipolysis in organ failure and to interpret the NEFA-TGFA correlations. RESULTS Patients with HTG-AP had higher serum NEFA and TG levels and more severe AP (19% vs. 7%; P < 0.03) than did individuals with AP of other etiologies. Correlations of long-chain unsaturated NEFAs with corresponding TGFAs increased with TG concentrations up to 500 mg/dL and declined thereafter. However, NEFA – TGFA × lipase correlations became stronger with TGs above 500 mg/dL. AP and intravenous lipase infusion in rodents caused lipolysis of circulating TGs to NEFAs. This led to multisystem organ failure, which was prevented by pancreatic TG lipase deletion or lipase inhibition. CONCLUSIONS HTG-AP is made severe by the NEFAs generated from intravascular lipolysis of circulating TGs. Strategies that prevent TG lipolysis may be effective in improving clinical outcomes for patients with HTG-AP. FUNDING National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, NIH) (RO1DK092460 and R01DK119646); Department of Defense (PR191945 under W81XWH-20-1-0400); National Institute on Alcohol Abuse and Alcoholism (NIAAA), NIH (R01AA031257).

Spinal cord stimulation (SCS), first used for pain relief in 1967, serves as an invasive neuromodulation with the targeted delivery of stimulations and the alertness of neural activities. Based on the gate-controlled theory of pain and multiple research studies, the application of SCS to motor recovery, pain relief, and sensory and cognitive restoration has been shown to be significant. Considering that movement disorders and pain are complications of various diseases, the categories, applications, and technical operation of SCS are coming of age. In terms of its impact on the immune system, SCS alters the trajectory of neurological diseases by modulating local immune responses through immunomodulatory mechanisms that vary depending on the different patterns of SCS. In addition to existing targets, the combinations of SCS and emerging techniques deepen the research at the molecular level, contributing to the exploration of potential targets and novel treatments. However, to secure a place in the future trend of non-invasive and precise treatment, it is necessary to improve SCS in terms of mechanism research, cost reduction, and application to more diseases.

ABSTRACT Herpes simplex virus is a large double-strand DNA virus that replicates in the nucleus of the host cell and interacts with host DNA replication and repair proteins. The viral 5′ to 3′ alkaline nuclease, UL12, is required for production of DNA that can be packaged into infectious virus. The UL12-deleted virus, AN-1, exhibits near wild-type levels of viral DNA replication, but the DNA cannot be packaged into capsids, suggesting it is structurally aberrant. To better understand the DNA replication defect observed in AN-1, we utilized isolation of proteins on nascent DNA (iPOND), a powerful tool to study all the proteins at a DNA replication fork. Combining iPOND with stable isotope labeling of amino acids in cell culture (SILAC) allows for a quantitative assessment of protein abundance when comparing wild type to mutant replication forks. We performed five replicates of iPOND-SILAC comparing AN-1 to the wild-type virus, KOS. We observed 60 proteins that were significantly lost from AN-1 forks out of over 1,000 quantified proteins. These proteins largely represent host DNA replication proteins including MCM2-7, RFC1-5, MSH2/6, MRN, and proliferating cell nuclear antigen. These observations are reminiscent of how these proteins behave at stalled human replication forks. We also observed similar protein changes when we stalled KOS forks with hydroxyurea. Additionally, we observed a decrease in the rate of AN-1 replication fork progression at the single-molecule level. These data indicate that UL12 is required for DNA replication fork progression and that forks stall in the absence of UL12. IMPORTANCE Herpes simplex virus 1 (HSV-1) is a near-ubiquitous pathogen within the global population, causing a lifelong latent infection with sporadic reactivation throughout the life of the host. Within at-risk and immunocompromised communities, HSV-1 infection can cause serious morbidities including herpes keratitis and encephalitis. With the possibility of herpesviruses to evade established antiviral therapies and there being no approved HSV-1 vaccine, there comes a need to investigate potential targets for intervention against infection and subsequent disease. UL12 is the viral 5'–3' exonuclease, which is required for the production of infectious progeny. In this study, we show that in the absence of UL12, viral replication fork progression is abrogated. These data point to UL12 as an attractive target for intervention, which could lead to better clinical outcomes of HSV-1-associated disease in the future.

Extremely severe nausea was experienced by four subjects positioned prone on a 7T scanner table with their arm extended overhead for a wrist examination and their head positioned approximately 10–20 cm above the magnet's central axis. Movement through the large static and spatial field gradients of current 7T MRI scanner magnets typically causes mild vestibular activation which is well tolerated by most individuals. However, when positioned off‐axis, the head moves through regions of even larger and more rapidly changing magnetic fields which in the current study were sufficient to induce the extremely severe nausea. Ensuring the head remains on‐axis mitigates this effect.

AbstractIntroductionLittle is known regarding the prevalence and prognostic implications of non‐sustained ventricular tachycardia (NSVT) in patients with wild‐type transthyretin cardiac amyloidosis (ATTRwt‐CA). We aimed to investigate the prevalence of NSVT in patients with ATTRwr‐CA, and the association of NSVT with sustained ventricular arrhythmias (VA) and all‐cause mortality.MethodsIn a cohort of ATTRwt‐CA patients from 2011 to 2022 without prior sustained VA, we ascertained the presence and characteristics of NSVT during clinically indicated ambulatory Holter monitoring. Patients were stratified based on the presence of NSVT at baseline. The primary and secondary endpoints of sustained VA and all‐cause mortality, respectively, were assessed during follow‐up.ResultsThe cohort included 217 patients with ATTRwt‐CA (95% males, median age 75 years; median NYHA class 2). Baseline Holter monitoring demonstrated NSVT in 116 (53%) patients. During a median follow‐up of 27 months (IQR 16–45) after the index Holter monitor, 11 (5.1%) patients reached the primary endpoint of sustained VA (incidence 1.8 per 100 person‐years, all monomorphic VT), and 46 (21%) patients died. In univariable Cox proportional hazard model, NYHA class 3 or 4 heart failure (p = .048), the presence of NSVT (p = .04), the duration of longest NSVT run (p = .029), and the percentage of ventricular ectopy (p < .001) were associated with the primary outcome. When adjusting for age and NYHA class 3 or 4 heart failure, the presence of NSVT remained associated with the primary outcome (p = .03). All‐cause mortality was not significantly different between patients with and without NSVT. A cutoff for ventricular ectopy burden of 0.5%, the median for all patients in this study, was associated with increased risk in sustained VA (log‐rank p = .004) and mortality (log‐rank p = .02).ConclusionNSVT is highly prevalent among ATTRwt‐CA patients undergoing clinically indicated Holter monitoring and may confer an increased risk of incident sustained VA.

AbstractObjectiveStereotactic radiosurgery (SRS) is increasingly used for small‐to‐medium‐sized sporadic vestibular schwannoma (VS) and is associated with good tumor control and low‐risk of adverse radiation‐associated events. The exact mechanism of VS tumor control is unknown but may relate to microvascular hyalinization and resultant tumoral ischemia. This study examined associations of microvascular risk factors with outcomes following SRS.DesignHistorical cohort of patients who underwent SRS for sporadic VS from 2000 to 2022.SettingTertiary academic center.MethodsAssociations of microvascular risk factors with tumor control and complications were evaluated using Cox proportional hazards regression.ResultsIn total 749 patients were studied, 31% with a history of smoking, 38% obesity, 19% hypertension, 8% diabetes, 3% peripheral vascular disease, and 2% history of coronary bypass. Regarding tumor control, no factor was associated with salvage treatment following SRS (n = 42). Hypertension (hazard ratio [HR] 2.81; P = .02) and coronary bypass (HR 6.91; P = .002) were significantly associated with developing facial nerve paresis (n = 22). No significant associations with new facial spasms (n = 53) were identified. Lastly, 191 of 294 patients with serviceable hearing at SRS progressed to nonserviceable hearing at a median 2.0 years (interquartile range: 1.0‐5.0). After multivariable adjustment for age and ipsilateral hearing status, the HR for the association of smoking history with time to nonserviceable hearing was 1.46 (95% confidence interval 1.04‐2.04; P = .03).ConclusionWe demonstrate that hypertension and history of coronary bypass may be associated with development of facial nerve weakness, while smoking may be associated with accelerated hearing loss in patients undergoing SRS for sporadic VS. These data may help guide patient counseling and inform decision‐making regarding treatment.

Abstract Objectives We aimed to improve the operational efficiency of clinical staff, including physicians and allied health professionals, in the previsit review of patients by implementing a disease-focused dashboard within the electronic health record system. The dashboard was tailored to the unique requirements of the clinic and patient population. Methods A prospective quality improvement study was conducted at an accredited pulmonary hypertension (PH) clinic within a large academic center, staffed by two full time physicians and two allied health professionals. Physicians' review time before and after implementation of the PH dashboard was measured using activity log data derived from an EHR database. The review time for clinic staff was measured through direct observation, with review method—either conventional or newly implemented dashboard—randomly assigned. Results Over the study period, the median number of patients reviewed by physicians per day increased slightly from 5.50 (interquartile range [IQR]: 1.35) before to 5.95 (IQR: 0.85) after the implementation of the PH dashboard (p = 0.535). The median review time for the physicians decreased with the use of the dashboard, from 7.0 minutes (IQR: 1.55) to 4.95 minutes (IQR: 1.35; p < 0.001). Based on the observed timing of 70 patient encounters among allied clinical staff, no significant difference was found for experienced members (4.65 minutes [IQR: 2.02] vs. 4.43 minutes [IQR: 0.69], p = 0.752), while inexperienced staff saw a significant reduction in review time after familiarization with the dashboard (5.06 minutes [IQR: 1.51] vs. 4.12 minutes [IQR: 1.99], p = 0.034). Subjective feedback highlighted the need for further optimization of the dashboard to align with the workflow of allied health staff to achieve similar efficiency benefits. Conclusion A disease-focused dashboard significantly reduced physician previsit review time while that for clinic staff remained unchanged. Validation studies are necessary with our patient populations to explore further qualitative impacts on patient care efficiency and long-term benefits on workflow.