A rapid method for the screening of fatty acids in lipids in plasma or serum without prior extraction.

Serum or plasma are the commonly used blood fractions to determine the relationship between dietary and circulating fatty acids in health and disease. Most methods available for the measurement of fatty acids in serum or plasma (referred to as serum henceforth) require prior extraction with organic solvents. We have determined that it is possible to directly convert the lipids in aqueous biological samples to fatty acid methyl esters (FAME) without prior extraction, providing that the ratio of serum to transmethylation solvent does not exceed 10%.

Prolactin Biology and Laboratory Measurement: An Update on Physiology and Current Analytical Issues.

Prolactin is a 23 kDa single chain protein of 199 amino acids synthesised and released principally by lactotrophs in the anterior pituitary gland. The secretion is mainly under inhibitory control by hypothalamic dopamine and regulated in a negative feedback manner, with prolactin itself providing the afferent signal: short-loop feedback. The main function of prolactin is during pregnancy and lactation in the development of mammary glands, milk synthesis and maintenance of milk secretion.

Cost effectiveness of high-sensitivity troponin compared to conventional troponin among patients presenting with undifferentiated chest pain: A trial based analysis.

Background: Patients with low and intermediate risk chest pain features comprise the greatest proportion presenting to emergency services for evaluation of suspected acute coronary syndromes (ACS). The efficient and timely identification of patients with these features remains a major challenge within clinical practice. Troponin assays are increasingly being used for the determination of risk among patients presenting with chest pain potentially facilitating more appropriate care.

Randomized Comparison of High-Sensitivity Troponin Reporting in Undifferentiated Chest Pain Assessment.

Background: High-sensitivity troponin T (hs-TnT) assays promise greater discrimination of evolving myocardial infarction, but the impact of unguided implementation on the effectiveness of care is uncertain.

Methods And Results: We evaluated the impact of hs-TnT reporting on care and outcome among chest pain patients presenting to 5 emergency departments within a multicenter randomized trial. Patients were allocated to hs-TnT reporting (hs-report) or standard reporting (std-report; Roche Elecys).

Consensus Statement for the Management and Communication of High Risk Laboratory Results.

Ineffective test follow-up is a major source of harm for patients around the world. Unreliable communication from medical laboratories (henceforth termed 'laboratories') to clinicians of results that represent critical or significant risk to patients (collectively termed 'high risk results') is a contributing factor to this problem. Throughout Australasia, management practices for such results vary considerably.

Fluorosis and periostitis deformans as complications of prolonged voriconazole treatment.

We describe a case of development of painful periostitis deformans in a 39-year-old woman who was receiving long-term voriconazole treatment for Aspergillus infection as a complication of orthotopic liver transplant. Measurement of fluoride levels strongly supports fluorosis to be the mechanism of the voriconazole-induced periostitis deformans and supports the concept that such measurements might be of use in predicting this complication of long-term voriconazole treatment.

High sensitivity-troponin elevation secondary to non-coronary diagnoses and death and recurrent myocardial infarction: An examination against criteria of causality.

Background: Myonecrosis provoked by illness unrelated to unstable coronary plaque is common, but uncertainty about a cause-effect relationship with future events challenges the appropriateness of initiating therapies known to be effective in cardiac conditions. We examined the causal relationship between troponin elevation in non-coronary diagnoses and late cardiac events using the Bradford Hills criteria for causality.

Methods And Results: Patients presenting acutely to South Australian public hospitals receiving at least one troponin between September 2011-September 2012 were included.

Study design of embracing high-sensitivity troponin effectively: the value of more information: a randomized comparison.

Background: The development of troponin assays with increased diagnostic sensitivity and greater analytic precision has improved the diagnosis of myocardial infarction in high risk patients. However for those patients at intermediate or low risk in whom a small troponin rise is detected, a cascade of clinical decisions and investigations could result; potentially having uncertain impact on recurrent ischemic events and increasing bleeding risk and resource utilization. Clinical equipoise remains as to the clinical utility of high sensitivity troponin.

Bone turnover markers.

Bones are constantly remodelled to cope with the body's calcium requirements and to repair microscopic damage. The entire skeleton is replaced every 10 years in adults, and around 10% of the skeleton is involved in bone remodelling at any one time.

Artifactually elevated serum bicarbonate results caused by elevated serum lactate dehydrogenase concentrations.

Background: An accurate estimation of serum bicarbonate concentration (HCO3(-)) is essential to the diagnosis and treatment of acid-base disorders and electrolyte disturbances. We noted significant discrepancies between HCO3(-) concentration measured by the Olympus AU2700 analyser and total serum carbon dioxide (TCO2) concentration derived from a Radiometer blood gas analyser on several patient samples. This was reported to the manufacturer which led to a recall of certain reagent lot numbers.

The correlation between third-trimester maternal and newborn-serum 25-hydroxy-vitamin D in a selected South Australian group of newborn samples.

Background: Although vitamin D insufficiency is prevalent in the community, only a few population-based studies have measured serum 25-hydroxy-vitamin D (25OHD) levels during pregnancy and in newborns. Maternal vitamin D deficiency has been linked to pregnancy complications, as well as hypocalcaemia and rickets in the newborn. Here, the authors report third-trimester maternal and newborn-serum 25OHD concentrations in 101 neonates whose serum samples were sent for testing.

Calcium supplements lower bone resorption after renal transplant.

Aim: Bone loss in renal transplant (RT) patients is a problem that begins during end-stage kidney disease and persists after transplantation. Suppression of parathyroid hormone (PTH) may decrease bone loss and improve fracture rate.

Methods: A single-group prospective intervention study involving 30 patients was performed at a large RT unit.

Physical and catalytic properties of a peroxidase derived from cytochrome c.

Except for its redox properties, cytochrome c is an inert protein. However, dissociation of the bond between methionine-80 and the heme iron converts the cytochrome into a peroxidase. Dissociation is accomplished by subjecting the cytochrome to various conditions, including proteolysis and hydrogen peroxide (H(2)O(2))-mediated oxidation.

Liver function tests.

This article forms part of our 'Tests and results' series for 2011 which aims to provide information about common tests that general practitioners order regularly. It considers areas such as indications, what to tell the patient, what the test can and cannot tell you, and interpretation of results. Liver function tests (LFTs) are a panel of blood markers (Table 1) used to assess and monitor several diseases.

Hyperparathyroidism and vitamin D deficiency predispose to bone loss in renal transplant recipients.

Background: Bone disease is common postrenal transplantation resulting in increased fracture rates and morbidity. The cause is multifactorial including hyperparathyroidism, corticosteroids, and possibly calcium and vitamin D deficiencies. The aim of this study was to identify modifiable factors contributing to bone disease in long-term renal transplant (RT) recipients.

Calcium malabsorption does not cause secondary hyperparathyroidism.

We challenge the widespread assumption that malabsorption of calcium per se causes secondary hyperparathyroidism. Serum parathyroid hormone (PTH) does not rise at the menopause despite the fall in calcium absorption, nor is it raised in osteoporotic women with vertebral fractures despite their low calcium absorption. The age-related rise in serum PTH can be accounted for by the age-related fall in serum 25(OH)D and/or decline in renal function with consequent loss of the calcemic action of vitamin D on bone.

A family of splice variants of CstF-64 expressed in vertebrate nervous systems.

Background: Alternative splicing and polyadenylation are important mechanisms for creating the proteomic diversity necessary for the nervous system to fulfill its specialized functions. The contribution of alternative splicing to proteomic diversity in the nervous system has been well documented, whereas the role of alternative polyadenylation in this process is less well understood. Since the CstF-64 polyadenylation protein is known to be an important regulator of tissue-specific polyadenylation, we examined its expression in brain and other organs.

Vitamin D metabolites and calcium absorption in severe vitamin D deficiency.

Contrary to frequent claims, vitamin D insufficiency does not generally cause malabsorption of calcium because serum 1,25(OH)(2)D, which is the major determinant of calcium absorption, is maintained by secondary hyperparathyroidism. Nevertheless, because malabsorption of calcium has been described in osteomalacia, there must be a 25(OH)D level below which the serum 1,25(OH)(2)D can no longer be sustained, although it has never been defined. This paper seeks to define it.

Neurodegeneration and peroxidases.

Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS) are neurodegenerative diseases that affect different parts of the central nervous system. However, a review of the literature indicates that certain biochemical reactions involved in neurodegeneration in these three diseases are quite similar and could be partly identical. This article critically examines the similarities and, based on data from our own and other laboratories, proposes a novel explanation for neurodegeneration in these three diseases.

Pituitary involvement in Wegener's granulomatosis.

Wegener's granulomatosis (WG) is an anti-neutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis of small and medium-sized vessels. Pituitary involvement in WG is rare with only 22 previous case reports in the English medical literature between 1966 and 2006. Herein we report another patient with WG-related diabetes insipidus (DI) and partial disruption of the anterior pituitary axes.

Bone loss after initiation of androgen deprivation therapy in patients with prostate cancer.

Context: Although androgen deprivation therapy (ADT) for prostate cancer is associated with bone loss, little is known about when this bone loss occurs.

Objective: We postulated that men on ADT would experience the greatest bone loss acutely after initiation of ADT.

Design And Setting: We conducted a 12-month prospective study at an academic medical center.

Role of peroxidases in Parkinson disease: a hypothesis.

Extensive research has been done to elucidate the underlying molecular events causing neurodegenerative diseases such as Parkinson disease, yet the cause and the individual steps in the progression of such diseases are still unknown. Here we advance the hypothesis that, rather than or in addition to inorganic radical molecules, heme-containing peroxidase enzymes may play a major role in the etiology of Parkinson disease. This hypothesis is based on the following considerations: (1) several heme-containing enzymes with peroxidase activity are present in the substantia nigra pars compacta; (2) these peroxidases have the ability to catalyze the oxidation of proteins and lipids; (3) certain heme peroxidases are known to destroy cells in vivo; (4) heme peroxidases have the stability and specificity that could account for the fact that specific molecules and cells are subject to damage in Parkinson disease, rather than a random destruction; (5) heme peroxidase activity could account for certain reactions in connection with parkinsonism that thus far have not been adequately explained; and (6) the participation of a heme peroxidase could explain some recent observations that are inconsistent with the oxyradical theory.