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Total parenteral nutrition (TPN) is a recognized treatment modality used for patients with impaired gastrointestinal function or patients whose nutrition needs cannot be met by enteral nutrition alone. TPN solutions [...]

Caprenin is a triglyceride that contains primarily caprylic (C8:0), capric (C10:0), and behenic (C22:0) acids and modest amounts of arachidic (C20:0) and lignoceric (C24:0) acids. Using the fat-balance technique, the absorption of C20:0, C22:0, and C24:0 was measured in 20 healthy adult men and women aged 20–60 years consuming a chocolate-flavored caprenin confection. The absorption values for these very long-chain fatty acids (VLCFAs) were determined based on measurements of their dietary intake and fecal excretion during a 5-day treatment period and a 7-day posttreatment washout period after correcting for baseline excretion of VLCFAs. Each subject consumed 4.7 g C20:0, 52.8 g C22:0, and 0.84 g C24:0 from the test confection during the treatment. Absorption averaged 41.6%± 3.6% (SEM) for C20:0, 28.8%± 4.4% for C22:0, and 14.8%± 3.9% for C24:0. Using a modification of the Atwater method, the physiological fuel value (caloric value) of caprenin was then calculated. This modified method takes into account the partial absorption of VLCFAs and the heat loss due to the metabolism of the medium-chain fatty acids C8:0 and C10:0. The results of this study demonstrate that the caloric value of caprenin is 5 kcal/g compared to the value of 9 kcal/g for other dietary triglycerides. [ABSTRACT FROM PUBLISHER]

A set of criteria is presented for the continuous monitoring of weft tension under dynamic weaving conditions on a conventional shuttle loom. A radio-telemetry system is developed that is designed for the direct measurement of weft tension within the shuttle itself. Components of the system that are described include the transducer, transmitter and amplifier, power supply, switchgear, and aerial; the assembly of these components within the shuttle and the relay of weft-tension traces to an external receiver and recording device are also discussed. The performance characteristics of the monitoring system are studied, and a typical trace of weft tension is related to the action of the various weaving mechanisms on a conventional loom. [ABSTRACT FROM AUTHOR]

Aggregation of amyloid β (Aβ) peptides into extracellular plaques is a hallmark of the molecular pathology of Alzheimer's disease (AD). Amyloid aggregates have been extensively studied in vitro, and it is well-known that mature amyloid fibrils contain an ordered parallel β structure. The structural evolution from unaggregated peptide to fibrils can be mediated through intermediate structures that deviate significantly from mature fibrils, such as antiparallel β-sheets. However, it is currently unknown if these intermediate structures exist in plaques, which limits the translation of findings from in vitro structural characterizations of amyloid aggregates to AD. This arises from the inability to extend common structural biology techniques to ex vivo tissue measurements. Here we report the use of infrared (IR) imaging, wherein we can spatially localize plaques and probe their protein structural distributions with the molecular sensitivity of IR spectroscopy. Analyzing individual plaques in AD tissues, we demonstrate that fibrillar amyloid plaques exhibit antiparallel β-sheet signatures, thus providing a direct connection between in vitro structures and amyloid aggregates in the AD brain. We further validate results with IR imaging of in vitro aggregates and show that the antiparallel β-sheet structure is a distinct structural facet of amyloid fibrils.

Amyloid plaques are one of the central manifestations of Alzheimer's disease pathology. Aggregation of the amyloid beta (Aβ) protein from amorphous oligomeric species to mature fibrils has been extensively studied. However, structural heterogeneities in prefibrillar species, and how that affects the structure of later-stage aggregates are not yet well understood. The integration of infrared spectroscopy with atomic force microscopy (AFM-IR) allows for identifying the signatures of individual nanoscale aggregates by spatially resolving spectra. We use AFM-IR to demonstrate that amyloid oligomers exhibit significant structural variations as evidenced in their infrared spectra. This heterogeneity is transmitted to and retained in protofibrils and fibrils. We show that amyloid fibrils do not always conform to their putative ordered structure and structurally different domains exist in the same fibril. We further demonstrate that these structural heterogeneities manifest themselves as a lack of β sheet structure in amyloid plaques in Alzheimer's tissue using infrared imaging.

The plasticity of the developing brain can be observed following injury to the motor cortex and/or corticospinal tracts, the most commonly injured brain area in the pre- or peri-natal period. Factors such as the timing of injury, lesion size and lesion location may affect a single hemisphere's ability to acquire bilateral motor representation. Bilateral motor representation of single hemisphere origin is most likely to occur if brain injury occurs before the age of 2 years; however, the link between injury aetiology, reorganization type and functional outcome is largely understudied. We performed a retrospective review to examine reorganized cortical motor maps identified through transcranial magnetic stimulation in a cohort of 52 patients. Subsequent clinical, anthropometric and demographic information was recorded for each patient. Each patient's primary hand motor cortex centre of gravity, along with the Euclidian distance between reorganized and normally located motor cortices, was also calculated. The patients were classified into broad groups including reorganization type (inter- and intrahemispheric motor reorganization), age at the time of injury (before 2 years and after 2 years) and injury aetiology (developmental disorders and acquired injuries). All measures were analysed to find commonalities between motor reorganization type and injury aetiology, function and centre of gravity distance. There was a significant effect of injury aetiology on type of motor reorganization ( P  < 0.01), with 60.7% of patients with acquired injuries and 15.8% of patients with developmental disorders demonstrating interhemispheric motor reorganization. Within the interhemispheric motor reorganization group, ipsilaterally and contralaterally projecting hand motor cortex centres of gravity overlapped, indicating shared cortical motor representation. Furthermore, the data suggest significantly higher prevalence of bilateral motor representation from a single hemisphere in cases of acquired injuries compared to those of developmental origin. Functional outcome was found to be negatively affected by acquired injuries and interhemispheric motor reorganization relative to their respective counterparts with developmental lesions and intrahemispheric motor reorganization. These results provide novel information regarding motor reorganization in the developing brain via an unprecedented cohort sample size and transcranial magnetic stimulation. Transcranial magnetic stimulation is uniquely suited for use in understanding the principles of motor reorganization, thereby aiding in the development of more efficacious therapeutic techniques to improve functional recovery following motor cortex injury., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Guarantors of Brain.)

Although crucial in improving health outcomes in the preterm infants, parenteral nutrition (PN) is not without risk, especially if handled improperly. A growing body of evidence suggests that components of PN admixtures, including lipid injectable emulsions (ILEs), are susceptible to degradation, including oxidation when exposed to light (ie, photo-oxidation), resulting in the production of reactive oxygen species. Infants, especially those born preterm, are considered more susceptible to consequences of oxidative stress than children and adults. Oxidative stress is associated with bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and intestinal failure-associated liver disease. The American Society for Parenteral and Enteral Nutrition (ASPEN) assembled a working group to provide recommendations on clinical practice surrounding photoprotection of PN.This Position Paper reviews the scientific literature on the formation of quantifiable peroxides and other degradation products when PN admixtures and ILEs are exposed to light and reports adverse clinical outcomes in premature infants exposed to PN. Recommendations for photoprotection of PN admixtures and ILEs are provided, as well as the challenges in achieving complete photoprotection with the equipment, supplies, and materials currently available in the US. ASPEN and the authors understand that the full implementation of complete photoprotection may not currently be feasible given current product availability; recommendations provided in this paper serve to represent the goal to which to strive as well as to highlight the importance of product availability to achieve these practices. This paper has been approved by the ASPEN Board of Directors., (© 2021 American Society for Parenteral and Enteral Nutrition.)

Coronavirus disease 2019 (COVID-19) has changed nutrition care processes in hospitals and in the home setting. This paper summarizes clinician reports on these changed processes, including overall nutrition care, nutrition assessment, enteral nutrition and parenteral nutrition care steps, and food and oral supplement delivery. Also included are teaching, logistics, and personnel issues around changes in the work environment. Use of safe, standardized, evidence-based processes in the face of altered care patterns is critical., (© 2020 American Society for Parenteral and Enteral Nutrition.)

The American Society for Parenteral and Enteral Nutrition defines standards as benchmarks representing a range of performance of competent care that should be provided to assure safe and efficacious nutrition care in most circumstances. Standards are documents that define the structure needed to provide competent care. These Standards for Nutrition Support for Adult Hospitalized Patients are an update of the 2010 Standards. These practice-based standards are intended for use by healthcare professionals charged with the care of adult hospitalized patients receiving nutrition support therapy in any hospital with or without a formal nutrition support service or team. These Standards address professional responsibilities as they relate to patient assessment, diagnosis, education, care plan development, implementation, clinical monitoring, evaluation, and professional issues around nutrition support., (© 2018 American Society for Parenteral and Enteral Nutrition.)

The commentary addresses discussion regarding the duration of infusion for lipid injectable emulsions (ILEs; previously known as intravenous fat emulsion) when administered separately from amino acids and dextrose (2:1) admixtures. The article by Mundi et al describes the administration time of ILEs administered separately as up to 24 hours, while previous American Society for Parenteral and Enteral Nutrition documents have outlined the infusion time not to exceed 12 hours., (© 2017 American Society for Parenteral and Enteral Nutrition.)

Parenteral nutrition (PN) is a highly complex medication and its provision can be prone to a variety of errors. Safe administration of this therapy requires that the competency of clinicians, particularly nurses, be demonstrated using a standardized process. In this document, a standardized model for PN administration competency is proposed based on a competency framework, the ASPEN-published interdisciplinary core competencies, discipline-specific standards of practice, safe practice recommendations, and clinical guidelines. ASPEN recognizes that all healthcare institutions may not currently meet the aspirational goals of this document. This framework will guide institutions and agencies in developing tools and procedures and maintaining competency of staff members around safe PN administration. The ASPEN Board of Directors has approved this document., (© 2018 American Society for Parenteral and Enteral Nutrition.)

Drug shortages continue to be a threat to the health and welfare of numerous patients in the United States. For patients who depend on parenteral nutrition (PN) for survival, these shortages pose an even greater threat. Almost 75% of active drug shortages are sterile injectables, which includes PN components. Providing PN therapy is particularly challenging for clinicians because this is a complex medication and may contain 40 or more individual ingredients, of which multiple components may simultaneously be in limited supply. The availability of PN components must be considered during every step of the PN use process from ordering the PN prescription to administering this therapy to a patient. Alterations to a standardized process can lead to medication errors that can adversely affect patient outcomes and consume healthcare resources., (© 2018 American Society for Parenteral and Enteral Nutrition.)

Parenteral nutrition (PN) is a complex, high-alert medication, and errors associated with the use of this therapy may lead to significant harm to patients. This document reviews error reports from the Institute for Safe Medication Practices' Medication Errors Reporting Program that are associated with the PN use process over the past 10 years. Actual PN-related errors are outlined, with most occurring in the PN-compounding/dispensing and PN administration steps. Clinicians involved in any phase of the PN use process should review their institutional or homecare company's processes for reporting of PN errors and collaborate with their medical safety officer and/or committees involved with medication error reporting.

Background: Lipid injectable emulsion (ILE) is an integral part of parenteral nutrition (PN), providing energy and essential fatty acids. With recent consensus recommendations for PN, clinical guidelines for ordering and preparation of PN, the U.S. Food and Drug Administration approval of new ILE products, and revised ILE labeling to include a 1.2-micron filter, a gap in current practice knowledge was apparent., Materials and Methods: The American Society for Parenteral and Enteral Nutrition PN Safety Committee surveyed clinicians on how ILE products are prescribed, prepared, and administered to patients from neonates to adults., Results: The results of this survey conducted in late 2016 found a wide variation in practice, particularly across patient age groups., Conclusion: These findings demonstrate the need for ongoing dissemination and education on standardized safe practices for ILE use.

Parenteral nutrition (PN) represents one of the most notable achievements of modern medicine, serving as a therapeutic modality for all age groups across the healthcare continuum. PN offers a life-sustaining option when intestinal failure prevents adequate oral or enteral nutrition. However, providing nutrients by vein is an expensive form of nutrition support, and serious adverse events can occur. In an effort to provide clinical guidance regarding PN therapy, the Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) convened a task force to develop consensus recommendations regarding appropriate PN use. The recommendations contained in this document aim to delineate appropriate PN use and promote clinical benefits while minimizing the risks associated with the therapy. These consensus recommendations build on previous ASPEN clinical guidelines and consensus recommendations for PN safety. They are intended to guide evidence-based decisions regarding appropriate PN use for organizations and individual professionals, including physicians, nurses, dietitians, pharmacists, and other clinicians involved in providing PN. They not only support decisions related to initiating and managing PN but also serve as a guide for developing quality monitoring tools for PN and for identifying areas for further research. Finally, the recommendations contained within the document are also designed to inform decisions made by additional stakeholders, such as policy makers and third-party payers, by providing current perspectives regarding the use of PN in a variety of healthcare settings.

Parenteral nutrition (PN) is a high-alert medication with a complex drug use process. Key steps in the process include the review of each PN prescription followed by the preparation of the formulation. The preparation step includes compounding the PN or activating a standardized commercially available PN product. The verification and review, as well as preparation of this complex therapy, require competency that may be determined by using a standardized process for pharmacists and for pharmacy technicians involved with PN. An American Society for Parenteral and Enteral Nutrition (ASPEN) standardized model for PN order review and PN preparation competencies is proposed based on a competency framework, the ASPEN-published interdisciplinary core competencies, safe practice recommendations, and clinical guidelines, and is intended for institutions and agencies to use with their staff., (© 2016 American Society for Parenteral and Enteral Nutrition.)