Understanding Breast Cancer Surgery Through Tiktok: an Analysis of Video Content and Viewer Engagement.

BACKGROUND: Breast cancer is the most common cancer in adolescents and young adults. Social media, particularly TikTok, has emerged as a crucial platform for sharing health information in this population. This study aims to characterize breast cancer surgery information on TikTok, focusing on content reliability, viewer reception, and areas for improvement. METHODS: We queried the search terms "breast cancer surgery," "mastectomy," and "lumpectomy" on TikTok, evaluating the top 50 videos for each. After watching each video, characteristics were recorded including: creator characteristics, video metrics, viewer reception, and video content. Statistical analysis was performed using Spearman's rank correlations and t-tests. RESULTS: A total of 138 videos were analyzed (excluding 12 duplicates from the initial 150). These videos received 4,895,373 likes and 109,705 comments. The most common content types were storytelling (57%) and education (20%), and the most common creator types were patients (77.3%) and physicians (10.3%). Videos with educational content by physicians were rare (6.5%). Engagement varied on the basis of video length, search terms, and creator characteristics. Overall, viewer comments predominantly expressed support and interest. CONCLUSIONS: Our study reveals that information on breast cancer surgery is widely shared on TikTok and has high viewer engagement. Factors influencing impact include video length, creator background, and search terms. While social media has democratized information sharing, there is a relative lack of physician creators providing objective and educational content. We highlight opportunities for health professionals to engage in social media as a tool for health education and ensure diverse and reliable healthcare content on these platforms.

Effects of food supplementation and helminth removal on space use and spatial overlap in wild rodent populations.

Animal space use and spatial overlap can have important consequences for population-level processes such as social interactions and pathogen transmission. Identifying how environmental variability and inter-individual variation affect spatial patterns and in turn influence interactions in animal populations is a priority for the study of animal behaviour and disease ecology. Environmental food availability and macroparasite infection are common drivers of variation, but there are few experimental studies investigating how they affect spatial patterns of wildlife. Bank voles (Clethrionomys glareolus) are a tractable study system to investigate spatial patterns of wildlife and are amenable to experimental manipulations. We conducted a replicated, factorial field experiment in which we provided supplementary food and removed helminths in vole populations in natural forest habitat and monitored vole space use and spatial overlap using capture-mark-recapture methods. Using network analysis, we quantified vole space use and spatial overlap. We compared the effects of food supplementation and helminth removal and investigated the impacts of season, sex and reproductive status on space use and spatial overlap. We found that food supplementation decreased vole space use while helminth removal increased space use. Space use also varied by sex, reproductive status and season. Spatial overlap was similar between treatments despite up to threefold differences in population size. By quantifying the spatial effects of food availability and macroparasite infection on wildlife populations, we demonstrate the potential for space use and population density to trade-off and maintain consistent spatial overlap in wildlife populations. This has important implications for spatial processes in wildlife including pathogen transmission.

Understanding The Role of Cognitive Load In Paramedical Contexts: A Systematic Review.

Objectives: Cognitive load refers to the working memory resources required during a task. When the load is too high or too low this has implications for an individual's task performance. In the context of paramedicine and emergency medical services (EMS) broadly, high cognitive load could potentially put patient and personnel safety at risk. This systematic review aimed to determine the current understanding of the role of cognitive load in paramedical contexts.Methods: To do this, five databases were searched (Elsevier Embase, ProQuest Psychology, CINAHL, Ovid Medline, and Ovid PsychINFO) using synonyms of cognitive load and paramedical contexts. Included articles were full text, peer reviewed empirical research, with a focus on cognitive load and EMS work. Two reviewers screened titles, abstracts, and full text using a traffic light system against the inclusion and exclusion criteria. The quality of evidence was assessed using the GRADE framework. This study was registered on PROSPERO (CRD42022384246). No funding was received for this research.Results: The searches identified 73 unique articles and after title/abstract and full text screening, 25 articles were included in the final review. Synthesis of the research revealed 10 categories of findings in the area. These are clinical performance, cognitive processes, emotional responses, physical expenditure, physiological responses, equipment and ergonomics, expertise and experience, multiple loads, cognitive load measures, and task complexity.Conclusions: From these findings it was determined that there is agreement in terms of what factors influence cognitive load in paramedical contexts, such as cognitive processes, task complexity, physical expenditure, level of experience, multiple types of loads, and the use of equipment. Cognitive load influences clinical task performance and has a bi-directional relationship with emotion. However, the literature is mixed regarding physiological responses to cognitive load, and how they are best measured. These findings highlight potential intervention points where cognitive load can be managed or reduced to improve working conditions for EMS clinicians and safety for their patients.

Cutaneous malakoplakia arising on the ankle of a patient with pyoderma gangrenosum.

Malakoplakia is a rare chronic inflammatory condition that most commonly involves the urogenital tract. Cutaneous malakoplakia is extremely rare and many patients diagnosed with skin involvement are immunosuppressed. While the clinical presentation of cutaneous malakoplakia is variable, the histopathologic features are quite distinct and include sheets of closely packed dermal histiocytes with foamy-appearing cytoplasm and Michaelis-Gutmann bodies that are positive with certain immunohistochemical stains. While the exact pathogenesis of malakoplakia is unknown, it has been associated with certain bacterial infections. Treatment generally involves a combination of surgery and antimicrobial agents and/or modulation of immunosuppressant therapy if appropriate. Herein, the authors report a unique case of cutaneous malakoplakia arising in a patient on chronic immunosuppressive therapy for the management of pyoderma gangrenosum.

A scoping review of direct oral anticoagulant ambulatory management practices.

Models of care for managing direct oral anticoagulant (DOAC) therapy are evolving. Little is known of what services are provided by anticoagulation managements services (AMS) for DOACs, or what necessitates comprehensive DOAC management and what differentiates it from usual care. The purpose of this scoping review was to describe services, management, or monitoring of DOACs distinct from prescriber-managed or usual care of DOACs. This scoping review reported followed the 2018 Preferred Reporting Items for Systematic Review and Meta-Analyses extension for scoping reviews (PRISMA-ScR). We searched PubMed, CINAHL, and EMBASE from inception to November 2020 to identify articles of interest. No language restriction was applied. Articles were included if they provided a description of DOAC management services, and described longitudinal anticoagulation follow-up that occurred in ambulatory care, community, or outpatient-related settings. Data was extracted from a total of 23 articles. The specific types of DOAC management interventions provided varied across the included studies. Nearly all studies described some form of DOAC therapy appropriateness assessment. Other common interventions included assessments of DOAC therapy compliance, adverse event triage and management, assessment of DOAC dosing appropriateness, periprocedural management of DOAC therapy, educational interventions, and renal function monitoring. A variety of DOAC management interventions were identified, but additional studies are needed to help health systems decide whether specific interventions performed by dedicated services are preferred over the usual care provided by clinicians prescribing DOAC therapy.

Remote Care Adoption in Underserved Congenital Heart Disease Patients During the COVID-19 Era.

The COVID-19 pandemic restricted in-person appointments and prompted an increase in remote healthcare delivery. Our goal was to assess access to remote care for complex pediatric cardiology patients. We performed a retrospective chart review of Texas Children's Hospital (TCH) pediatric cardiology outpatient appointments from March 2020 to December 2020 for established congenital heart disease (CHD) patients 1 to 17 yo. Primary outcome variables were remote care use of telemedicine and patient portal activation. Primary predictor variables were age, sex, insurance, race/ethnicity, language, and location. Descriptive statistics were used to analyze patient demographics. Multivariate logistic regression determined associations with remote care use (p < 0.05). We identified 5,410 established patients with clinic appointments during the identified timeframe. Adopters of telemedicine included 13% of patients (n = 691). Of the prior non patient portal users, 4.5% activated their accounts. On multivariate analysis, older age (10-17 yo) was associated with increased telemedicine (OR 2.04, 95%CI 1.71, 2.43) and patient portal use (OR 1.70, 95%CI 1.33, 2.17). Public insurance (OR 1.66, 95%CI 1.25, 2.20) and Spanish speaking were associated with increased patient portal adoption. Race/ethnicity was not significantly associated with telemedicine use or patient portal adoption. Telehealth adoption among older children may be indicative of their ability to aid in the use of these technologies. Higher participation in patient portal activation among publicly insured and Spanish speaking patients is encouraging and demonstrates ability to navigate some degree of remote patient care. Adoption of remote patient care may assist in reducing access to care disparities.

Morphology and Size of Bacterial Colonies Control Anoxic Microenvironment Formation in Porous Media.

Bacterial metabolisms using electron acceptors other than oxygen (e.g., methanogenesis and fermentation) largely contribute to element cycling and natural contaminant attenuation/mobilization, even in well-oxygenated porous environments, such as shallow aquifers. This paradox is commonly explained by the occurrence of small-scale anoxic microenvironments generated by the coupling of bacterial respiration and dissolved oxygen (O2) transport by pore water. Such microenvironments allow facultative anaerobic bacteria to proliferate in oxic environments. Microenvironment dynamics are still poorly understood due to the challenge of directly observing biomass and O2 distributions at the microscale within an opaque sediment matrix. To overcome these limitations, we integrated a microfluidic device with transparent O2 planar optical sensors to measure the temporal behavior of dissolved O2 concentrations and biomass distributions with time-lapse videomicroscopy. Our results reveal that bacterial colony morphology, which is highly variable in flowing porous systems, controls the formation of anoxic microenvironments. We rationalize our observations through a colony-scale Damköhler number comparing dissolved O2 diffusion and a bacterial O2 uptake rate. Our Damköhler number enables us to predict the pore space fraction occupied by anoxic microenvironments in our system for a given bacterial organization.

Chromium Cycling in Redox-Stratified Basins Challenges δ53Cr Paleoredox Proxy Applications.

Chromium stable isotope composition (δ53Cr) is a promising tracer for redox conditions throughout Earth's history; however, the geochemical controls of δ53Cr have not been assessed in modern redox-stratified basins. We present new chromium (Cr) concentration and δ53Cr data in dissolved, sinking particulate, and sediment samples from the redox-stratified Lake Cadagno (Switzerland), a modern Proterozoic ocean analog. These data demonstrate isotope fractionation during incomplete (non-quantitative) reduction and removal of Cr above the chemocline, driving isotopically light Cr accumulation in euxinic deep waters. Sediment authigenic Cr is isotopically distinct from overlying waters but comparable to average continental crust. New and published data from other redox-stratified basins show analogous patterns. This challenges assumptions from δ53Cr paleoredox applications that quantitative Cr reduction and removal limits isotope fractionation. Instead, fractionation from non-quantitative Cr removal leads to sedimentary records offset from overlying waters and not reflecting high δ53Cr from oxidative continental weathering.

The effects of real-time performance feedback and performance emphasis on the sustained attention to response task (SART).

The sustained attention to response task (SART) has been used for over 20 years to assess participants' response times and inability to withhold to No-Go stimuli (commission errors). While there is debate in the literature regarding what causes commissions errors in the SART, there is agreement the SART is subject to a speed-accuracy trade-off (SATO). Researchers have demonstrated that performance on the SART can be influenced by directive instructions to participants to prioritize either speed or accuracy during the task. In the present study, we investigated whether real-time performance feedback and whether feedback emphasis (emphasizing speed or accuracy) affected participants' response times and accuracy. We found performance feedback per se had no impact on performance, but performance emphasis did affect performance, apparently shifting the SATO. This finding provides further evidence that the commission errors in the SART are not indicative of sustained attention or vigilance as those terms are commonly used in the literature, but more likely assess response strategy and motor control (or lack of motor control). These findings have implications for the psychological assessment literature, as well as applied areas where SART findings have been utilized such as shoot/no-shoot decision making.

Chemosynthetic symbiont with a drastically reduced genome serves as primary energy storage in the marine flatworm Paracatenula.

Hosts of chemoautotrophic bacteria typically have much higher biomass than their symbionts and consume symbiont cells for nutrition. In contrast to this, chemoautotrophic Candidatus Riegeria symbionts in mouthless Paracatenula flatworms comprise up to half of the biomass of the consortium. Each species of Paracatenula harbors a specific Ca Riegeria, and the endosymbionts have been vertically transmitted for at least 500 million years. Such prolonged strict vertical transmission leads to streamlining of symbiont genomes, and the retained physiological capacities reveal the functions the symbionts provide to their hosts. Here, we studied a species of Paracatenula from Sant'Andrea, Elba, Italy, using genomics, gene expression, imaging analyses, as well as targeted and untargeted MS. We show that its symbiont, Ca R. santandreae has a drastically smaller genome (1.34 Mb) than the symbiont´s free-living relatives (4.29-4.97 Mb) but retains a versatile and energy-efficient metabolism. It encodes and expresses a complete intermediary carbon metabolism and enhanced carbon fixation through anaplerosis and accumulates massive intracellular inclusions such as sulfur, polyhydroxyalkanoates, and carbohydrates. Compared with symbiotic and free-living chemoautotrophs, Ca R. santandreae's versatility in energy storage is unparalleled in chemoautotrophs with such compact genomes. Transmission EM as well as host and symbiont expression data suggest that Ca R. santandreae largely provisions its host via outer-membrane vesicle secretion. With its high share of biomass in the symbiosis and large standing stocks of carbon and energy reserves, it has a unique role for bacterial symbionts-serving as the primary energy storage for its animal host.

Patient preferences and adherence to adjuvant GnRH analogs among premenopausal women with hormone receptor positive breast cancer.

PURPOSE: Adjuvant ovarian function suppression (OFS) in premenopausal hormone receptor (HR) positive breast cancer (BC) improves survival. Adherence to adjuvant gonadotropin-releasing hormone analogs (GnRHa) remains a challenge and is associated with toxicities and inconvenient parenteral administration. The goal of this study was to describe real-world adherence patterns and patient preferences surrounding adjuvant GnRHa. METHODS: We analyzed the medical records of premenopausal women with non-metastatic HR positive BC from January 2000 to December 2017; participants received adjuvant monthly goserelin or leuprolide at The Ohio State University. Data collected included demographics, clinicopathologic characteristics, and OFS adherence/side effects. We defined non-adherence as discontinuation of GnRHa within 3 years for a reason other than switching to an alternate OFS, delay > 7 days from a dose, or a missed dose. Chi-square tests assessed associations between clinical characteristics and outcomes. RESULTS: A total of 325 patients met eligibility. Of these, 119 (37%) patients were non-adherent to GnRHa; 137 (42%) underwent elective bilateral salpingo-oophorectomy after initial GnRHa. Those opting for surgery reported significantly more hot flashes (74% vs 48%, p < 0.001), arthralgias (46% vs 30%, p = 0.003), and vaginal dryness (37% vs 21%, p = 0.001) compared with patients remaining on GnRHa. CONCLUSION: Non-adherence to adjuvant GnRHa occurred in over a third of patients and almost half the patients initiating GnRHa underwent subsequent surgical ablation. These high frequencies highlight real-world patterns of OFS. Additionally, treatment toxicities may impact personal preference of OFS modality. Personalized practices to target predictors of adjuvant GnRHa non-adherence are critical to optimize symptoms, adherence, and survivorship.

HIV and HCV augments inflammatory responses through increased TREM-1 expression and signaling in Kupffer and Myeloid cells.

Chronic infection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) affects an estimated 35 million and 75 million individuals worldwide, respectively. These viruses induce persistent inflammation which often drives the development or progression of organ-specific diseases and even cancer including Hepatocellular Carcinoma (HCC). In this study, we sought to examine inflammatory responses following HIV or HCV stimulation of macrophages or Kupffer cells (KCs), that may contribute to virus mediated inflammation and subsequent liver disease. KCs are liver-resident macrophages and reports have provided evidence that HIV can stimulate and infect them. In order to characterize HIV-intrinsic innate immune responses that may occur in the liver, we performed microarray analyses on KCs following HIV stimulation. Our data demonstrate that KCs upregulate several innate immune signaling pathways involved in inflammation, myeloid cell maturation, stellate cell activation, and Triggering Receptor Expressed on Myeloid cells 1 (TREM1) signaling. TREM1 is a member of the immunoglobulin superfamily of receptors and it is reported to be involved in systemic inflammatory responses due to its ability to amplify activation of host defense signaling pathways. Our data demonstrate that stimulation of KCs with HIV or HCV induces the upregulation of TREM1. Additionally, HIV viral proteins can upregulate expression of TREM1 mRNA through NF-кB signaling. Furthermore, activation of the TREM1 signaling pathway, with a targeted agonist, increased HIV or HCV-mediated inflammatory responses in macrophages due to enhanced activation of the ERK1/2 signaling cascade. Silencing TREM1 dampened inflammatory immune responses elicited by HIV or HCV stimulation. Finally, HIV and HCV infected patients exhibit higher expression and frequency of TREM1 and CD68 positive cells. Taken together, TREM1 induction by HIV contributes to chronic inflammation in the liver and targeting TREM1 signaling may be a therapeutic option to minimize HIV induced chronic inflammation.

Corticosterone response by Peromyscus mice to parasites, reproductive season, and age.

A common response to parasite infestations is increased production of glucocorticoid hormones that regulate immune function. We examined relationships between ectoparasite infestations and fecal corticosterone metabolites (FCM) in deer mice (Peromyscus maniculatus). Furthermore, we experimentally removed fleas to determine if reductions in ectoparasites affected FCM production. Individuals were assigned to control (no flea removal) or treatment (anti-flea application, physical combing) groups and individuals were recaptured to assess changes in FCM concentrations. There was a significant and negative effect of number of anti-flea treatment applications on FCM concentrations of deer mice. However, models including host biology traits and environmental predictors had a better model fit compared to models containing ectoparasite predictors. In particular, there was a significant relationship of deer mouse FCM with date and host age, where glucocorticoid production decreased towards the end of the breeding season and increased with age. Overall, adverse events associated with reproduction and age class, rather than ectoparasites, may be more important to variation in glucocorticoids of deer mice.

SARS-CoV-2 Wave Two Surveillance in East Asia and the Pacific: Longitudinal Trend Analysis.

BACKGROUND: The COVID-19 pandemic has had a profound global impact on governments, health care systems, economies, and populations around the world. Within the East Asia and Pacific region, some countries have mitigated the spread of the novel coronavirus effectively and largely avoided severe negative consequences, while others still struggle with containment. As the second wave reaches East Asia and the Pacific, it becomes more evident that additional SARS-CoV-2 surveillance is needed to track recent shifts, rates of increase, and persistence associated with the pandemic. OBJECTIVE: The goal of this study is to provide advanced surveillance metrics for COVID-19 transmission that account for speed, acceleration, jerk, persistence, and weekly shifts, to better understand country risk for explosive growth and those countries who are managing the pandemic successfully. Existing surveillance coupled with our dynamic metrics of transmission will inform health policy to control the COVID-19 pandemic until an effective vaccine is developed. We provide novel indicators to measure disease transmission. METHODS: Using a longitudinal trend analysis study design, we extracted 330 days of COVID-19 data from public health registries. We used an empirical difference equation to measure the daily number of cases in East Asia and the Pacific as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R. RESULTS: The standard surveillance metrics for Indonesia, the Philippines, and Myanmar were concerning as they had the largest new caseloads at 4301, 2588, and 1387, respectively. When looking at the acceleration of new COVID-19 infections, we found that French Polynesia, Malaysia, and the Philippines had rates at 3.17, 0.22, and 0.06 per 100,000. These three countries also ranked highest in terms of jerk at 15.45, 0.10, and 0.04, respectively. CONCLUSIONS: Two of the most populous countries in East Asia and the Pacific, Indonesia and the Philippines, have alarming surveillance metrics. These two countries rank highest in new infections in the region. The highest rates of speed, acceleration, and positive upwards jerk belong to French Polynesia, Malaysia, and the Philippines, and may result in explosive growth. While all countries in East Asia and the Pacific need to be cautious about reopening their countries since outbreaks are likely to occur in the second wave of COVID-19, the country of greatest concern is the Philippines. Based on standard and enhanced surveillance, the Philippines has not gained control of the COVID-19 epidemic, which is particularly troubling because the country ranks 4th in population in the region. Without extreme and rigid social distancing, quarantines, hygiene, and masking to reverse trends, the Philippines will remain on the global top 5 list of worst COVID-19 outbreaks resulting in high morbidity and mortality. The second wave will only exacerbate existing conditions and increase COVID-19 transmissions.

Low-cost automated capillary electrophoresis instrument assembled from commercially available parts.

A CE instrument that can be assembled from commercially available components with minimal construction effort is described. Except for the electronic control circuitry no specially made parts are required. It is based on a flexible design of microfluidic, electropneumatic, and electronic sections and different configurations can easily be implemented. Automated injection into the capillary is performed hydrodynamically by the application of a pressure for a controlled length of time. The performance of the device was tested with a contactless conductivity detector by separating different metal ions. In addition, nine metal cations related to the quality of honey were separated in 2.3 min and four honey samples were analysed quantitatively to demonstrate the applicability of the method.

Dark aerobic sulfide oxidation by anoxygenic phototrophs in anoxic waters.

Anoxygenic phototrophic sulfide oxidation by green and purple sulfur bacteria (PSB) plays a key role in sulfide removal from anoxic shallow sediments and stratified waters. Although some PSB can also oxidize sulfide with nitrate and oxygen, little is known about the prevalence of this chemolithotrophic lifestyle in the environment. In this study, we investigated the role of these phototrophs in light-independent sulfide removal in the chemocline of Lake Cadagno. Our temporally resolved, high-resolution chemical profiles indicated that dark sulfide oxidation was coupled to high oxygen consumption rates of ~9 µM O2 ·h-1 . Single-cell analyses of lake water incubated with 13 CO2 in the dark revealed that Chromatium okenii was to a large extent responsible for aerobic sulfide oxidation and it accounted for up to 40% of total dark carbon fixation. The genome of Chr. okenii reconstructed from the Lake Cadagno metagenome confirms its capacity for microaerophilic growth and provides further insights into its metabolic capabilities. Moreover, our genomic and single-cell data indicated that other PSB grow microaerobically in these apparently anoxic waters. Altogether, our observations suggest that aerobic respiration may not only play an underappreciated role in anoxic environments but also that organisms typically considered strict anaerobes may be involved.

The Effects of Morphine, Baclofen, and Buspirone Alone and in Combination on Schedule-Controlled Responding and Hot Plate Antinociception in Rats.

Better therapeutic options are needed for pain. Baclofen, buspirone, and morphine are characterized as having analgesic properties. However, little is known about potential interactions between analgesic effects of these drugs when combined. Furthermore, it is not known if the magnitude of these potential interactions will be similar for all drug effects. Thus, we tested the effects of these drugs alone and in combination for their capacity to produce thermal antinociception and to decrease food-maintained responding. Four male and four female Sprague-Dawley rats responded for food under a fixed-ratio 10 schedule; afterward they were immediately placed on a 52°C hot plate. Morphine, baclofen, and buspirone were examined alone and in 1:1 combinations, based upon ED50 values. Morphine and baclofen effects were evaluated with the opioid antagonist naltrexone and the GABAB antagonist (3-Aminopropyl)(diethoxymethyl)phosphinic acid (CGP35348), respectively. Morphine, baclofen, and buspirone dose dependently decreased operant responding, with the calculated ED50 values being 7.09, 3.42, and 0.57 mg/kg, respectively. The respective antinociception ED50 values were 16.15, 8.75, and 2.20 mg/kg. Analysis of 1:1 combinations showed the effects of morphine plus baclofen to decrease schedule-controlled responding and to produce thermal antinociception were synergistic. Effects of morphine plus buspirone and baclofen plus buspirone to decrease schedule-controlled responding were additive. Effects of the two combinations to produce thermal antinociception were synergistic. Naltrexone and CGP35348 antagonized the effects of morphine and baclofen, respectively. Synergistic antinociceptive effects, in conjunction with additive effects on food-maintained responding, highlight the therapeutic utility of opioid and non-opioid drug combinations.

Injection system for fast capillary electrophoresis based on pressure regulation with flow restrictors.

A fast automated system for rapid electrophoretic separations in short conventional capillaries employing contactless conductivity detection is presented. The instrument is based on pneumatic pressurization and does not require a conventional pump. The required pressures and flow rates for the different steps of the injection and flushing processes are produced with the help of two flow restrictors. The device is implemented on a microfluidic breadboard with dimensions of ca. 13 × 20 cm and employs miniature valves. Nine inorganic cations, namely NH4+, K+ , Na+ , Ca2+ , Mg2+ , Mn2+ , Sr2+ , Li+ , and Ba2+ , could be separated in a capillary of 10 µm inner diameter and 6 cm effective length within 25 s. Following a reduction of the effective length to 4 cm, still five inorganic cations could be separated in a time span of 12 s. The repeatability of peak areas was better than 3.1 % and limits of detection between 3.5 and 5.5 µM were achieved.

Matrix-assisted laser desorption/ionization imaging mass spectrometry of intraperitoneally injected danegaptide (ZP1609) for treatment of stroke-reperfusion injury in mice.

RATIONALE: This work focuses on direct matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) detection of intraperitoneally (IP)-injected dipeptide ZP1609 in mouse brain tissue. Direct analysis of drug detection in intact tissue sections provides distribution information that can impact drug development. MALDI-IMS capabilities of uncovering drug transport across the blood-brain barrier are demonstrated. METHODS: Successful peptide detection using MALDI-IMS was achieved using a MALDI TOF/TOF system. Upon optimization of sample preparation procedures for dipeptide ZP1609, an additional tissue acidification procedure was found to greatly enhance signal detection. The imaging data acquired was able to determine successful transport of ZP1609 across the blood-brain barrier. Data obtained from MALDI-IMS can help shape our understanding of biological functions, disease progression, and effects of drug delivery. RESULTS: Direct detection of ZP1609 throughout the brain tissue sections was observed from MALDI-MS images. However, in cases where there was induction of stroke, a peak of lower signal intensity was also detected in the target m/z region. Although distinct differences in signal intensity can be seen between control and experimental groups, fragments and adducts of ZP1609 were investigated using MALDI-IMS to verify detection of the target analyte. CONCLUSIONS: Overall, the data reveals successful penetration of ZP1609 across the blood-brain barrier. The benefits of tissue acidification in the enhancement of detection sensitivity for low-abundance peptides were demonstrated. MALDI-IMS has been shown to be a useful technique in the direct detection of drugs within intact brain tissue sections.

You are measuring the decision to be fast, not inattention: the Sustained Attention to Response Task does not measure sustained attention.

The Sustained Attention to Response Task (SART) has been widely used in psychological literature as a measure of vigilance (the ability to sustain attention over a prolonged period of time). This task uses a Go/No-Go paradigm and requires the participants to repetitively respond to the stimuli as quickly and as accurately as possible. Previous literature indicates that performance in SART is subjected to a "speed-accuracy trade-off" (SATO) resulting from strategy choices and from the failures of controlling motor reflexes. In this study, 36 participants (n = 36) performed a series of four SARTs. The results support the perspective of strategy choice in SART and suggest that within-subjects SATO in SART should also be acknowledged in attempting to explain SART performance. The implications of the speed-accuracy trade-off should be fully understood when the SART is being used as a measure or tool.