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Modeling of water movement in non-saturated soil usually requires a large number of parameters and variables, such as initial soil water content, saturated water content and saturated hydraulic conductivity, which can be assessed relatively easily. Dimensional flow of water in the soil is usually modeled by a nonlinear partial differential equation, known as the Richards equation. Since this equation cannot be solved analytically in certain cases, one way to approach its solution is by numerical algorithms. The success of numerical models in describing the dynamics of water in the soil is closely related to the accuracy with which the water-physical parameters are determined. That has been a big challenge in the use of numerical models because these parameters are generally difficult to determine since they present great spatial variability in the soil. Therefore, it is necessary to develop and use methods that properly incorporate the uncertainties inherent to water displacement in soils. In this paper, a model based on fuzzy logic is used as an alternative to describe water flow in the vadose zone. This fuzzy model was developed to simulate the displacement of water in a non-vegetated crop soil during the period called the emergency phase. The principle of this model consists of a Mamdani fuzzy rule-based system in which the rules are based on the moisture content of adjacent soil layers. The performances of the results modeled by the fuzzy system were evaluated by the evolution of moisture profiles over time as compared to those obtained in the field. The results obtained through use of the fuzzy model provided satisfactory reproduction of soil moisture profiles.

Introduction: Conduction system pacing (CSP), often accomplished with lumenless pacing leads, is increasingly employed to achieve physiologic ventricular activation. There are limited data on the extraction of these leads. The objective of this study was to describe the safety and efficacy of extraction of CSP pacing leads and compare outcomes with extraction of non-CSP lumenless leads., Methods: Patients undergoing CSP/non-CSP lumenless lead removal were included. Outcomes of interest included rates of complete procedural success, complications, and successful reimplantation., Results: Overall, 23 patients were included (n = 14 with CSP and n = 9 with non-CSP lumenless leads implanted in the right atrium, right ventricle, or septum). The mean age was 52.7 ± 24.0 years, 30% were female, and the mean lead age was 4.5 ± 4.4 years. The complete procedural success rate was 100%. One serious complication occurred in the non-CSP group but was unrelated to the lead of interest. Manual traction alone was successful in 57% of CSP cases (mean lead age 2.4 ± 1.7 years) and in 11% of non-CSP cases (mean lead age 7.9 ± 5.3 years). Laser sheaths were used in 43% of CSP cases and 89% of non-CSP cases; rotational cutting tools were used in no CSP cases and in 33% of non-CSP cases. Reimplantation in the conduction system was attempted with a left bundle branch pacing lead and successful in 80% (n = 4/5)., Conclusion: Extraction of CSP and non-CSP lumenless leads is feasible with a high success rate and a good safety profile. CSP reimplantation after extraction is also feasible with good electrical performance., (© 2024 Wiley Periodicals LLC.)

Background: Binding sites in the costoclavicular space are commonly encountered during transvenous lead extraction. Severe adhesions may warrant use of more aggressive rotational cutting tools or surgical intervention. It is not known whether preprocedural multidetector computed tomography (MDCT) can provide information about the likelihood that a patient will require costoclavicular intervention., Objective: The purpose of this study was to determine whether there are preprocedural MDCT findings associated with need for intervention in the costoclavicular space during lead extraction., Methods: Patients who underwent lead extraction and required use of stiffer rotational cutting tools (TightRail Sub-C) or surgical intervention in the costoclavicular space as well as age- and sex-matched controls who did not require intervention were included. Preprocedural MDCT was evaluated for patterns of lead tethering to bone and adjacent calcification., Results: Overall, 56 patients were included (n = 20 Sub-C only, n = 8 surgical intervention, and n = 28 matched controls). The mean patient age of interventional cases was 65.0 ± 14.7 years, 18% were female, and the mean lead age was 12.3 ± 6.2 years. Four major patterns were identified on imaging: lead surrounded 360° by fat (intervention rate, 5/24 patients); lead tethered to bone by <180° (11/19); no tethering of lead but with associated calcifications (3/4); and lead tethered to bone by >180° (9/9). Tethering of at least 1 lead to bone by >180° was associated with a 100% rate of costoclavicular intervention and the highest rate of surgical intervention (56%). Absence of any degree of bone tethering was associated with a 0% rate of surgical intervention., Conclusion: Computed tomography captures details of costoclavicular binding that appear to correlate with the need for adjunctive extraction techniques, including surgical intervention. Computed tomography may be useful in preprocedural planning for adhesions in the costoclavicular space., Competing Interests: Disclosures Dr Lewis serves as a consultant to Philips. Dr Pokorney receives research support from Medtronic, Boston Scientific, and Philips and serves as a consultant to Biosense Webster, Boston Scientific, Medtronic, Philips, Milestone, and Zoll. Dr Piccini receives grants for clinical research from Abbott, the American Heart Association, Boston Scientific, iRhythm, and Philips and serves as a consultant to ABVF, Abbott, AbbVie, Boston Scientific, Element Science, ElectroPhysiology Frontiers, Kardium, Medtronic, Milestone, Sanofi, Pacira, Philips, and Up-to-Date., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

In the US, <20% of cancers are diagnosed by standard-of-care (SoC) screening. Multicancer early detection (MCED) tests offer the opportunity to expand cancer screening. Understanding the characteristics and clinical outcomes of MCED-detected cancers is critical to clarifying MCED tests' potential impact. DETECT-A is the first prospective interventional trial of an MCED blood test (CancerSEEK). CancerSEEK, coupled with diagnostic PET-CT, identified cancers including those not detected by SoC screening, the majority of which were localized or regional. We report multiyear outcomes in patients with cancers diagnosed following a positive CancerSEEK test. Nine cancer types were diagnosed in 26 participants whose cancers were first detected by CancerSEEK. Information on cancer diagnoses, treatments, and clinical outcomes was extracted from medical records through November 2022. Data collection occurred at a median of 4.4 years (IQR: 4.1-4.6) following study enrollment. Thirteen of 26 (50%) participants were alive and cancer-free [ovarian (4), thyroid (1), uterine (2), breast (1), colorectal (2), and lung (3)]; 7/13 (54%) had cancers without recommended SoC screening modalities. All eight treated stage I or II participants (8/8, 100%) and 12/14 (86%) surgically treated participants were alive and cancer-free. Eligibility for surgical treatment was associated with favorable multiyear outcomes (P = 0.0002). Half of participants with MCED-detected cancers were alive and cancer-free after 4.4 years median follow-up. Most were diagnosed with early-stage cancers and were treated surgically. These results suggest that early cancer detection by CancerSEEK may have facilitated curative-intent treatments and associated positive clinical outcomes in some DETECT-A participants. Prevention Relevance: This study provides preliminary evidence of the potential of multicancer early detection testing as an effective screening tool for detecting cancers without standard-of-care (SoC) screening modalities and complementing SoC cancer screening., (©2024 The Authors; Published by the American Association for Cancer Research.)

Guideline recommended standard of care screening is available for four cancer types; most cancer-related deaths are caused by cancers without standard of care screening. DETECT-A is the first prospective interventional trial evaluating a multi-cancer early detection (MCED) blood test (CancerSEEK) in women without a history of cancer, providing the first opportunity to assess the long-term outcomes of individuals with false-positive (FP) MCED results. This prospective analysis of DETECT-A participants with FP results evaluates the performance of an imaging-based diagnostic workflow and examines cancer risk following a FP result. This analysis included all DETECT-A participants with a positive CancerSEEK test and subsequent flourine-18 fluorodeoxyglucose positron emission tomography-IV contrast-enhanced computed tomography (18-F-FDG PET-CT) imaging and clinical workup indicating no evidence of cancer within 1 year of enrollment (n = 98). Medical records, study interactions, and study surveys were used to assess cancer incidence, treatments, and clinical outcomes through August 2023. Ninety-five of 98 participants with a FP result remained cancer-free with a median follow-up of 3.6 years (IQR: 2.5-4.1) from determination of FP status. Three incident cancers were observed over the follow-up period. One bilateral stage IIIC ovarian cancer was diagnosed 1.9 years after determination of FP status; two stage I breast cancers were diagnosed 0.1 and 1.6 years from determination of FP status. The annual incidence rate of cancer during follow-up from FP determination was 1.0% (95% confidence interval, 0.2%-2.8%). Participants with a positive CancerSEEK test who underwent 18-F-FDG PET-CT and clinical workup without cancer findings had low risk for cancer over the following several years. Prevention Relevance: This study provides multiyear clinical outcomes data following a false-positive multi-cancer early detection test for individuals participating in a prospective interventional trial. It provides a preliminary performance assessment of an imaging-based diagnostic workflow following a false-positive multi-cancer early detection test., (©2024 The Authors; Published by the American Association for Cancer Research.)

Background and Objectives: The Friedreich ataxia (FRDA) scientific community needs access to patient-centered outcome measures that satisfy regulatory guidelines and are capable of tracking clinically meaningful changes in FRDA disease burden. The objective of this research was to develop a novel, disease-specific caregiver-reported outcome measure for use in FRDA research and clinical care., Methods: In prior work, we conducted qualitative interviews and a cross-sectional study of FRDA caregivers and patients to determine the symptoms of greatest importance to individuals with FRDA. We designed the Friedreich Ataxia Caregiver-Reported Health Index (FACR-HI) to serially measure the symptoms of greatest importance to patients and utilized factor analysis, beta testing, reliability testing, and cross-sectional subgroup analysis to further evaluate and optimize this disease-specific outcome measure., Results: The FACR-HI was designed to measure total disease burden and disease burden in 18 symptomatic domains. The FACR-HI total score demonstrated high internal consistency (Cronbach's α = 0.98) and test-retest reliability (intraclass correlation coefficient = 0.96). Beta interview participants found the FACR-HI to be highly relevant, comprehensive, and easy to use. FACR-HI total and subscale scores were associated with functional staging for ataxia scores and speech impairment., Discussion: Initial evaluation of the FACR-HI supports its content validity, test-retest reliability, and construct validity as a caregiver-reported outcome measure for assessing how pediatric individuals with FRDA feel and function. The FACR-HI provides a potential mechanism to quantify changes in multifactorial FRDA disease burden during future clinical trials., Competing Interests: S. Subramony receives research support from the NIH, FDA, Wyck, Friedreich’s Ataxia Research Alliance, Muscular Dystrophy Association, Facioscapulohumeral Muscular Dystrophy Society, National Ataxia Foundation, Reata, PTC, Retrotope, Biohaven, Takeda, Acceleron, Pharnext, Avidity, and Reneo. He has provided consultation or served on advisory boards for Dyne, Avidity, Reata, and AveXis; D.R. Lynch receives grant support from the NIH, FDA, Friedreich’s Ataxia Research Alliance, Reata Pharmaceuticals, Retrotope, PTC Therapeutics, and Design Pharmaceuticals; and C.R. Heatwole receives royalties for the use of multiple disease-specific instruments. He has provided consultation to Biogen Idec, Ionis Pharmaceuticals, aTyr Pharma, AMO Pharma, Acceleron Pharma, Cytokinetics, Expansion Therapeutics, Harmony Biosciences, Regeneron Pharmaceuticals, Astellas Pharmaceuticals, AveXis, Recursion Pharmaceuticals, IRIS Medicine, Inc., Takeda Pharmaceutical Company, Scholar Rock, Avidity Biosciences, Novartis Pharmaceuticals Corporation, SwanBio Therapeutics, Neurocrine Biosciences, Sanofi, Lupin Pharmaceuticals, and the Marigold Foundation. He receives grant support from the Department of Defense, Duchenne UK, Parent Project Muscular Dystrophy, Recursion Pharmaceuticals, Swan Bio Therapeutics, Sanofi, Lupin Pharmaceuticals, the National Institute of Neurological Disorders and Stroke, the Muscular Dystrophy Association, the Friedreich's Ataxia Research Alliance, Cure Spinal Muscular Atrophy, the Amyotrophic Lateral Sclerosis Association, the University of Miami, Novartis Pharmaceuticals Corporation, and the Michael J. Fox Foundation. He is the director of the University of Rochester's Center for Health and Technology. Full disclosure form information provided by the authors is available with the full text of this article at Neurology.org/cp., (© 2024 American Academy of Neurology.)

Background: Recruiting large cohorts efficiently can speed the translation of findings into care across a range of scientific disciplines and medical specialties. Recruitment can be hampered by factors such as financial barriers, logistical concerns, and lack of resources for patients and clinicians. These and other challenges can lead to underrepresentation in groups such as rural residents and racial and ethnic minorities. Here we discuss the implementation of various recruitment strategies for enrolling participants into a large, prospective cohort study, assessing the need for adaptations and making them in real-time, while maintaining high adherence to the protocol and high participant satisfaction., Methods: While conducting a large, prospective trial of a multi-cancer early detection blood test at Geisinger, an integrated health system in central Pennsylvania, we monitored recruitment progress, adherence to the protocol, and participants' satisfaction. Tracking mechanisms such as paper records, electronic health records, research databases, dashboards, and electronic files were utilized to measure each outcome. We then reviewed study procedures and timelines to list the implementation strategies that were used to address barriers to recruitment, protocol adherence and participant satisfaction., Results: Adaptations to methods that contributed to achieving the enrollment goal included offering multiple recruitment options, adopting group consenting, improving visit convenience, increasing the use of electronic capture and the tracking of data and source documents, staffing optimization via leveraging resources external to the study team when appropriate, and integrating the disclosure of study results into routine clinical care without adding unfunded work for clinicians. We maintained high protocol adherence and positive participant experience as exhibited by a very low rate of protocol deviations and participant complaints., Conclusion: Recruiting rapidly for large studies - and thereby facilitating clinical translation - requires a nimble, creative approach that marshals available resources and changes course according to data. Planning a rigorous assessment of a study's implementation outcomes prior to study recruitment can further ground study adaptations and facilitate translation into practice. This can be accomplished by proactively and continuously assessing and revising implementation strategies., (© 2024. The Author(s).)

The rat surgical anterior cruciate ligament transection (ACLT) model is commonly used to investigate intra-articular osteoarthritis (OA) therapies, and histological assessment is often the primary outcome measure. However, histological changes do not always correlate well with clinical outcomes. Therefore, this study evaluated functional outcomes in the rat surgical ACLT model and compared intra-articular injection volumes ranging from 20 to 50 μl. Unilateral ACLT was surgically induced and static weight-bearing, mechanical allodynia, motor function, and gait were assessed in four groups of male, Sprague-Dawley rats (n = 6 per group). Intra-articular injections of 20 µl Dulbecco's phosphate-buffered saline (DPBS), 50 µl DPBS, or 50 µl of synthetic biomimetic boundary lubricant were administered once weekly for 3 weeks postoperatively. Structural changes were evaluated histologically at 20 weeks. Rat cadaver knees were injected with 20, 30, 40, or 50 µl of gadolinium solutions and were imaged using magnetic resonance imaging (MRI). Static weight-bearing, mechanical allodynia, and gait parameters in ACLT groups revealed differences from baseline and naïve controls for 4 weeks post-ACLT; however, these differences did not persist beyond 6 weeks. Different intra-articular DPBS injection volumes did not result in functional or histological changes; however, peri-articular leakage was documented via MRI following 50, 40, and 30 µl but not 20 µl gadolinium injections. Statement of clinical significance: Differences in functional parameters were predominantly restricted to early, postoperative changes in the rat surgical ACLT model despite evidence of moderate histologic OA at 20 weeks. Injection volumes of 20-30 µl are more appropriate for investigating intra-articular therapies in the rat knee., (© 2022 Orthopaedic Research Society. Published by Wiley Periodicals LLC.)

Background: Timely differentiation of biliary atresia (BA) from other infantile cholestatic diseases can impact patient outcomes. Additionally, non-invasive staging of fibrosis after Kasai hepatoportoenterostomy has not been widely standardized. Shear wave elastography is an ultrasound modality that detects changes in tissue stiffness. The authors propose that the utility of elastography in BA can be elucidated through meta-analysis of existing studies., Aim: To assess the utility of elastography in: (1) BA diagnosis, and (2) post-Kasai fibrosis surveillance., Methods: A literature search identified articles that evaluated elastography for BA diagnosis and for post-Kasai follow-up. Twenty studies met criteria for meta-analysis: Eleven for diagnosis and nine for follow-up post-Kasai. Estimated diagnostic odds ratio (DOR), sensitivity, and specificity of elastography were calculated through a random-effects model using Meta-DiSc software., Results: Mean liver stiffness in BA infants at diagnosis was significantly higher than in non-BA, with overall DOR 24.61, sensitivity 83%, and specificity 79%. Post-Kasai, mean liver stiffness was significantly higher in BA patients with varices than in patients without, with DOR 16.36, sensitivity 85%, and specificity 76%. Elastography differentiated stage F4 fibrosis from F0-F3 with DOR of 70.03, sensitivity 96%, and specificity 89%. Elastography also differentiated F3-F4 fibrosis from F0-F2 with DOR of 24.68, sensitivity 85%, and specificity 81%., Conclusion: Elastography has potential as a non-invasive modality for BA diagnosis and surveillance post-Kasai. This paper's limitations include inter-study method heterogeneity and small sample sizes. Future, standardized, multi-center studies are recommended., Competing Interests: Conflict-of-interest statement: There are no conflicts of interest to report., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Major depressive disorder (MDD) is predominantly managed in primary care. However, primary care providers (PCPs) may not consistently follow evidence-based treatment algorithms, leading to variable patient management that can impact outcomes., Methods: We retrospectively analyzed adult patients with MDD seen at Geisinger, an integrated health system. Utilizing electronic health record (EHR) data, we classified patients as having MDD based on International Classification of Disease (ICD)-9/10 codes or a Patient Health Questionnaire (PHQ)-9 score ≥5. Outcomes assessed included time to first visit with a PCP or behavioral health specialist following diagnosis, antidepressant medication switching, persistence, healthcare resource utilization (HRU), and treatment costs., Results: Among the 38,321 patients with MDD managed in primary care in this study, significant delays between diagnosis with antidepressant prescribing and follow-up PCP visits were observed. There was also considerable variation in care following diagnosis. Overall, 34.9% of patients with an ICD-9/10 diagnosis of MDD and 41.3% with a PHQ-9 score ≥15 switched antidepressants. An ICD-9/10 diagnosis, but not moderately severe to severe depression, was associated with higher costs and HRU. More than 75% of patients with MDD discontinued antidepressant medication within 6 months., Limitations: The study population was comparable with other real-world studies of MDD, but study limitations include its retrospective nature and reliance on the accuracy of EHRs., Conclusions: Management of patients with MDD in a primary care setting is variable. Addressing these gaps will have important implications for ensuring optimal patient management, which may reduce HRU and treatment medication costs, and improve treatment persistence., (Copyright © 2021. Published by Elsevier B.V.)

Abstract: Structural racism has received renewed focus over the past year, fueled by the convergence of major political and social events. Psychiatry as a field has been forced to confront a legacy of systemic inequities. Here, we use examples from our clinical and supervisory work to highlight the urgent need to integrate techniques addressing racial identity and racism into psychiatric practice and teaching. This urgency is underlined by extensive evidence of psychiatry's long-standing systemic inequities. We argue that our field suffers not from a lack of available techniques, but rather a lack of sustained commitment to understand and integrate those techniques into our work; indeed, there are multiple published examples of strategies to address racism and racial identity in psychiatric clinical practice. We conclude with recommendations geared toward more firmly institutionalizing a focus on racism and racial identity in psychiatry, and suggest applications of existing techniques to our initial clinical examples., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Intravesical administration of interleukin 12 (IL-12) co-formulated with the biopolymer, chitosan (CS/IL-12), has demonstrated remarkable antitumor activity against preclinical models of bladder cancer. However, given historical concerns regarding severe toxicities associated with systemic IL-12 administration in clinical trials, it is important to evaluate the safety of intravesical CS/IL-12 prior to clinical translation., Objective: To evaluate the pharmacokinetics as well as the local and systemic toxicities of intravesical CS/IL-12 immunotherapy in laboratory mice., Methods: Local inflammatory responses in mouse bladders treated with intravesical IL-12 or CS/IL-12 were assessed via histopathology. Serum cytokine levels following intravesical and subcutaneous (s.c.) administrations of IL-12 or CS/IL-12 in laboratory mice were compared. Systemic toxicities were evaluated via body weight and liver enzyme levels., Results: Intravesical IL-12 and CS/IL-12 treatments did not induce significant local or systemic toxicity. IL-12 dissemination and exposure from intravesical administration was significantly lower compared to s.c. injections. Weekly intravesical CS/IL-12 treatments were well-tolerated and did not result in blunted immune responses., Conclusions: Intravesical CS/IL-12 is safe and well-tolerated in mice. In particular, the lack of cystitis and acute inflammation justifies continued investigation of intravesical CS/IL-12 immunotherapy in larger animals and patients with bladder cancer., Competing Interests: K.G.N., E.S.W., M.R.V., S.M.M., D.M.M., and D.A.Z. declare that they have no conflicts of interest with the contents of this article., (© 2021 – The authors. Published by IOS Press.)

Abstract: Public trust in the credibility of medicine and physicians has been severely tested amid the COVID-19 pandemic and growing sociopolitical fissures in the United States. Physicians are being asked to be ambassadors to the public of scientific information. Psychiatrists have an opportunity to help the public understand and accept a "new normal" during a time of such uncertainty. Using a case example, we review the impact of uncertainty and fear on scientific and medical credibility. Although the pandemic provides an opportunity for systemic change, the consequences of any change remain unknown. To help patients navigate the uncertainty, we conclude by offering four guidelines to clinicians: the public has little interest in understanding the scientific method; we need to acknowledge that we do not have all the answers; credibility and trustworthiness are linked to our ability to be trusted, believable messengers; and we can retain scientific credibility while acknowledging uncertainty., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Interleukin-12 (IL-12) is a potent, pro-inflammatory type 1 cytokine that has long been studied as a potential immunotherapy for cancer. Unfortunately, IL-12's remarkable antitumor efficacy in preclinical models has yet to be replicated in humans. Early clinical trials in the mid-1990's showed that systemic delivery of IL-12 incurred dose-limiting toxicities. Nevertheless, IL-12's pleiotropic activity, i.e., its ability to engage multiple effector mechanisms and reverse tumor-induced immunosuppression, continues to entice cancer researchers. The development of strategies which maximize IL-12 delivery to the tumor microenvironment while minimizing systemic exposure are of increasing interest. Diverse IL-12 delivery systems, from immunocytokine fusions to polymeric nanoparticles, have demonstrated robust antitumor immunity with reduced adverse events in preclinical studies. Several localized IL-12 delivery approaches have recently reached the clinical stage with several more at the precipice of translation. Taken together, localized delivery systems are supporting an IL-12 renaissance which may finally allow this potent cytokine to fulfill its considerable clinical potential. This review begins with a brief historical account of cytokine monotherapies and describes how IL-12 went from promising new cure to ostracized black sheep following multiple on-study deaths. The bulk of this comprehensive review focuses on developments in diverse localized delivery strategies for IL-12-based cancer immunotherapies. Advantages and limitations of different delivery technologies are highlighted. Finally, perspectives on how IL-12-based immunotherapies may be utilized for widespread clinical application in the very near future are offered., (Copyright © 2020 Nguyen, Vrabel, Mantooth, Hopkins, Wagner, Gabaldon and Zaharoff.)

We present a case of a neonate with tracheoesophageal fistula and esophageal atresia along with a suspicious lung mass who had a false-positive newborn screen for cystic fibrosis due to an elevated serum immunoreactive trypsinogen with an additionally elevated serum lipase. The infant's lung mass was found to contain heterotopic pancreatic tissue consisting of acini, ducts, and islet cells, without an associated gastrointestinal duplication cyst. This constellation of congenital abnormalities has not been described in previous literature. Also, this is the first reported case of a neonate with elevated serum pancreatic enzymes in which the underlying etiology was discovered to be heterotopic pancreas.

Objective: We sought to examine the relationship between preoperative platelet function and perioperative bleeding in patients undergoing CABG., Background: There are many ways to measure platelet aggregability. Little is known about their correlations with one another, or with bleeding., Methods: We prospectively studied 50 patients undergoing a first isolated off-pump CABG. Thirty-four were exposed to a thienopyridine prior to surgery; 16 were not. Preoperative platelet function was measured by VerifyNow®, TEG®, AggreGuide™, Plateletworks®, vasodilator-stimulated phosphoprotein (VASP) phosphorylation, and light transmission aggregometry. Bleeding was assessed 2 ways: drop from pre- to nadir postoperative hematocrit, and chest tube drainage. Correlation coefficients were calculated using Spearman's rank-order correlation., Results: Mean age was 62 years. Patient characteristics and surgical details were similar between the thienopyridine-exposed and non-exposed patients. The correlation coefficients between the 4 point-of-care platelet function measurements and hematocrit change ranged from -0.2274 to 0.2882. Only Plateletworks® correlated with drop in hematocrit (r = 0.2882, P = 0.0470). The correlation coefficients between each of the 4 point-of-care platelet function tests and the chest tube drainage were also poor, ranging from -0.3073 to 0.2272. Both AggreGuide™ (r = -0.3073, P = 0.0317) and VASP (r = -0.3187, P = 0.0272) were weakly but significantly correlated with chest tube drainage. The correlation among the 4 point-of-care platelet function measurements was poor, with coefficients ranging from -0.2504 to 0.1968., Conclusions: We observed little correlation among 4 platelet function tests, and between those assays and perioperative bleeding defined 2 different ways. Whether any of these assays should be used to guide decision making in individual patients is unclear., (© 2015, Wiley Periodicals, Inc.)

Radioactively labelled ascorbic acid and dehydroascorbic acid, when incubated with human blood, migrate irreversibly into human red blood cells. Isolation and characterization of the moieties trapped within the cells via infrared spectroscopy established both their identities as L-ascorbic acid. Evidence in the form of the degree of in vitro entrapment of ascorbic acid as a function of the times of incubation and the effect of incubation temperature, anion recognition site inhibitor, and active transport inhibitor on the rate of entrapment support the hypothesis that ascorbic acid is oxidized on or near the surface of the red blood cell to dehydroascorbic acid which migrates through the lipid portion of the cell wall and is reduced back to ascorbic acid within the cell. The resulting L-ascorbic acid can not pass through the cell wall and is therefore entrapped.

Benzylpenicillin, 5.2% 14C-enriched, was incubated with human whole blood. The erythrocyte component was washed and exhaustively dialyzed and found to contain 6.3% of the original radioactivity. None of the penicillin was found to bind to the cell membrane. Dialysis of the cell contents indicated that none of the penicillin binds irreversibly to the proteins within the cell. Infrared examination of the contents of the cell leads to the conclusion that benzylpenicillin (a monovalent anion) enters the erythrocyte and is hydrolyzed to benzylpenicilloic acid (a divalent anion). This structural change prevents the antibiotic from migrating out of the cell.