Human granulocyte-macrophage colony-stimulating factor (hGM-CSF): identification of a binding site for a neutralizing antibody.

One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition.     

Lung preservation solution substrate composition affects rat lung oxidative metabolism during hypothermic storage

Lungs harvested for transplantation utilize oxygen after procurement. We investigated the effects of storage solution substrate composition on pulmonary oxidative metabolism and energetics during the preservation interval. Rat lungs were harvested and stored at 10 degrees C in low-potassium dextran (LPD) solution. Groups of lungs were preserved with preservation solution containing 5mM carbon-13 ((13)C) labeled glucose or increasing concentrations of (13)C labeled pyruvate. Additional groups of rat lungs were studied with dichloroacetate (DCA) added to the pyruvate-modified preservation solutions. Oxidative metabolism (measured by (13)C-enrichment of glutamate) and adenine nucleotide levels were quantified. Increasing preservation solution pyruvate concentration augmented glutamate (13)C-enrichment up to a concentration of 32mM pyruvate. DCA further stimulated oxidative metabolism only at lower concentrations of pyruvate (4 and 8mM). ATP and ADP were not different among groups, but AMP levels were higher in the glucose group. These data suggest that altering the substrate composition of the preservation solution influences lung metabolism during allograft preservation for transplantation.     

Analysis of neomycins A, B and C by high-performance liquid chromatography with post-column reaction detection

The analysis of the antibiotics neomycins A, B and C was investigated. The separation of the components was studied using reversed-phase and reversed-phase ion-pair chromatography. The optimum separation was obtained utilizing a Lichrosorb RP-2 column with a mobile phase consisting of 75 mg/l sodium dodecyl sulphate, 0.5M Na2SO4 and 0.015 M sodium acetate buffer at pH 7.0. Using this mobile phase, baseline separation was obtained for all three compounds in approximately 20 min. Detection was via post-column derivatization of the analytes with ortho-phthalaldehyde in the presence of mercaptoethanol to form fluorescent iso-indole products. This system is applied to the analysis of a number of formulated products containing neomycin.     

Associations between admissions factors and the need for remediation

Advances in Health Sciences Education - This study examines the way in which student characteristics and pre-admissions measures are statistically associated with the likelihood a student will...     

Lactation Patterns in Women with Hypertensive Disorders of Pregnancy: An Analysis of Illinois 2012–2015 Pregnancy Risk Assessment Monitoring System (PRAMS) Data

Maternal and Child Health Journal - Hypertensive disorders of pregnancy have lifelong implications on maternal cardiovascular health. Breastfeeding has a variety of maternal benefits, including...     

UK food and nutrition security during and after the COVID‐19 pandemic

The COVID‐19 pandemic is a major shock to society in terms of health and economy that is affecting both UK and global food and nutrition security. It is adding to the ‘perfect storm’ of threats to society from climate change, biodiversity loss and ecosystem degradation, at a time of considerable change, rising nationalism and breakdown in international collaboration. In the UK, the situation is further complicated due to Brexit. The UK COVID‐19 Food and Nutrition Security project, lasting one year, is funded by the Economic and Social Research Council and is assessing the ongoing impact of COVID‐19 on the four pillars of food and nutrition security: access, availability, utilisation and stability. It examines the food system, how it is responding, and potential knock on effects on the UK’s food and nutrition security, both in terms of the cascading risks from the pandemic and other threats. The study provides an opportunity to place the initial lessons being learnt from the on‐going responses to the pandemic in respect of food and nutrition security in the context of other long‐term challenges such as climate change and biodiversity loss.     

Efficacy of intracytoplasmic sperm injection using intentionally cryopreserved epididymal spermatozoa

Microsurgical epididymal sperm aspiration was a great advancein the therapy of patients with non-recon-structable, obstructiveazoospermia, most notably congenital bilateral absence of thevas deferens. Using conventional in-vitro fertilization, pregnancieswere rarely achieved because the rate of oocyte fertilizationwas extremely poor. However, the use of retrieved spermatozoain conjunction with intracytoplasmic sperm injection (ICSI)has dramatically increased the likelihood of embryo formation.Typically, sperm and oocyte harvesting are performed simultaneously.We have investigated whether frozen-thawed spermatozoa workas well as fresh spermatozoa. When we had concluded from ourown population of patients (groups I and II) that they did,we adopted a policy of aspirating spermatozoa, primarily cryopreservingthem and using them for ICSI at a later date. We found the fertilizationrates of this latter cohort of patients (group III) to be excellent(37% per oocyte), and the ongoing pregnancy rate is quite satisfactory(40 % per couple, 29% per cycle). We offer this approach asan alternative to the traditional scheme because it markedlyeases the burden of partner scheduling on both the couple andthe clinicians involved. In addition, assurance of the availabilityof male partner spermatozoa can be attained prior to beginningovulation induction.