Whole blood analysis of phagocytosis, apoptosis, cytokine production, and leukocyte subsets in healthy older men and women: the ZENITH study

Few studies to date have examined age-related changes in markers of immune status in healthy older individuals. The immune status of 93 healthy individuals aged 55–70 years was assessed by two- and three-color flow cytometry and biochemical analysis. There were significant age effects (p ≤.05) on monocyte phagocytic activity and cluster of differentiation (CD) 3/human leukocyte antigen-D-related (HLA-DR) late-activated T lymphocytes (% expression). There was a significant (p ≤ 0.1) Age x Sex interaction in absolute counts (x 10⁹/L) of CD3/CD8 total cytotoxic T lymphocytes (CTL), the CD4 T- helper to CD8 CTL ratio, the CD3/CD4/CD45RA naïve T helper to CD3/CD4/CD45RO memory T helper lymphocyte ratio, and interleukin (IL)-1ß (% expression) by activated monocytes. The study shows that alterations in markers of immune status occur between 55 and 70 years, and provides reference values for the lymphocyte measures in healthy men and postmenopausal women in this age group. The study further highlights the need for sex-specific reference ranges for such markers.

Selective chemical measurement based upon chemiluminescence detection

This thesis describes the utilisation of chemiluminescence (chemically generated light) for clinical diagnosis and process monitoring. Innovative instrumentation was developed for the direct monitoring of toxin levels in patients undergoing haemodialysis. This unique approach enables the efficacy of individual treatments to be continuously assessed thus enhancing patient outcomes.

Helicobacter pylori-associated hypochlorhydria in children, and development of iron deficiency

Aims Acute Helicobacter pylori infection is associated with transient hypochlorhydria. In H pylori-associated atrophy, hypochlorhydria has a role in iron deficiency (ID) through changes in the physiology of iron-complex absorption. The aims were to evaluate the association between H pylori-associated hypochlorhydria and ID in children. Methods Symptomatic children (n=123) were prospectively enrolled. Blood, gastric juice and gastric biopsies were taken, respectively, for haematological analyses, pH assessment and H pylori determination, and duodenal biopsies for exclusion of coeliac disease. Stool samples were collected for parasitology/microbiology. Thirteen children were excluded following parasitology and duodenal histopathology, and five due to impaired blood analysis. Results Ten children were hypochlorhydric (pH>4) and 33 were H pylori positive. In H pylori-positive children with pH>4 (n=6) serum iron and transferrin saturation levels % were significantly lower (p<0.01) than H pylori-positive children with pH≤4. No differences in ferritin, or total iron binding capacity, were observed. In H pylori-negative children with pH>4, iron and transferrin saturation were not significantly different from children with pH≤4. Conclusions Low serum iron and transferrin in childhood H pylori infection is associated with hypochlorhydria. In uninfected children, hypochlorhydria was not associated with altered serum iron parameters, indicating a combination of H pylori infection and/or inflammation, and hypochlorhydria has a role in the aetiology of ID. Although H pylori-associated hypochlorhydria is transient during acute gastritis, this alters iron homeostasis with clinical impact in developing countries with a high H pylori prevalence.

The relationship between patient blood pathology values and patient falls in an acute-care setting : a retrospective analysis

Few studies have investigated the relationship between patient falls and patient blood pathology values, which can reveal objective information about the health and nutritional status of a patient. It could be that some abnormal values are associated with patients that fall. The objectives of the current study were to determine whether blood pathology values were different in patients who fell compared to patients who did not fall, and whether there was a difference in the type and number of currently documented risk factors for falls found for patients who fell compared to patients who did not fall. A retrospective audit of patient incident reports and medical records was conducted in an acute-care hospital for 220 patients who fell and who did not fall. Faller and non-faller patients were matched by casemix type and length of stay. Findings revealed a significant relationship between patients who fell and the variables of age, confusion status and alkaline phosphatase blood values.

Bivariate variance-component analysis, with application to systolic blood pressure and total cholesterol levels in the Framingham Heart Study

Background :
The correlations between systolic blood pressure (SBP) and total cholesterol levels (CHOL) might result from genetic or environmental factors that determine variation in the phenotypes and are shared by family members. Based on 330 nuclear families in the Framingham Heart Study, we used a multivariate normal model, implemented in the software FISHER, to estimate genetic and shared environmental components of variation and genetic and shared environmental correlation between the phenotypes. The natural logarithm of the phenotypes measured at the last visit in both Cohort 1 and 2 was used in the analyses. The antihypertensive treatment effect was corrected before adjustment of the systolic blood pressure for age, sex, and cohort.
Results :
The univariate correlation coefficient was statistically significant for sibling pairs and parent-offspring pairs, but not significant for spouse pairs. In the bivariate analysis, the cross-trait correlation coefficients were not statistically significant for all relative pairs. The shared environmental correlation was statistically significant, but the genetic correlation was not significant.
Conclusion :
There is no significant evidence for a close genetic correlation between systolic blood pressure and total cholesterol levels. However, some shared environmental factors may determine the variation of both phenotypes.

Seasonal changes in the diet of the long-nosed bandicoot (Perameles nasuta) assessed by analysis of faecal scats and of stable isotopes in blood

The diet of long-nosed bandicoots (Perameles nasuta) on the central coast of New South Wales, Australia, was examined over two summers and two winters using a combination of faecal scat analysis for food fragments and stable isotope analysis (ratios of ¹³C/¹²C and ¹⁵N/¹⁴N) of blood. Isotope ratios in blood overlapped most strongly with those in invertebrate prey, and varied much less between seasons than did those in most dietary items, suggesting that the assimilated diet of long-nosed bandicoots is dominated by invertebrates throughout the year. Invertebrate remains dominated collected faeces in both seasons, even though the availability of invertebrate prey was higher in summer. Thus both techniques indicated that long-nosed bandicoots were primarily insectivorous year-round. Faecal scat analysis indicated that invertebrate eggs were more abundant in summer than winter. At a finer scale, spiders, orthopterans, lepidopteran larvae, ants, leaf material (non-grass monocot) and seeds were more abundant in summer, while cicada larvae, roots, fungi, grass leaves and Acacia bract (small modified leaves appearing as scales) were more abundant in winter. Subterranean foods (cicada larvae, plant roots and hypogeous fungi) were more abundant in winter and more abundant in the diet of males than of either lactating or non-lactating females.

Functional analysis of proteins involved in Plasmodium falciparum merozoite invasion of red blood cells

Plasmodium falciparum causes the most lethal form of malaria in humans and is responsible for over two million deaths per year. The development of a vaccine against this parasite is an urgent priority and potential protein targets include those on the surface of the asexual merozoite stage, the form that invades the host erythrocyte. The development of methods to transfect P. falciparum has enabled the construction of gain-of-function and loss-of-function mutants and provided new strategies to analyse the role of parasite proteins. In this review, we describe the use of this technology to examine the role of merozoite antigens in erythrocyte invasion and to address their potential as vaccine candidates.

Methods for the analysis of histone H3 and H4 acetylation in blood

LBH589 is one of the many histone deacetylase inhibitors (HDACi) that are currently in clinical trial. Despite their wide-spread use, there is little literature available describing the typical levels of histone acetylation in untreated peripheral blood, the treatment and storage of samples to retain optimal measurement of histone acetylation nor methods by which histone acetylation analysis may be monitored and measured during the course of a patient’s treatment. In this study, we have used cord or peripheral blood as a source of human leukocytes, performed a comparative analysis of sample processing methods and developed a flow cytometric method suitable for monitoring histone acetylation in isolated lymphocytes and liquid tumors. Western blotting and immunohistochemistry techniques have also been addressed. We have tested these methods on blood samples collected from four patients treated with LBH589 as part of an Australian Children’s Cancer Clinical Trial (CLBH589AAU03T) and show comparable results when comparing in vitro and in vivo data. This paper does not seek to correlate histone acetylation levels in peripheral blood with clinical outcome but describes methods of analysis that will be of interest to clinicians and scientists monitoring the effects of HDACi on histone acetylation in blood samples in clinical trials or in related research studies.

Association of early childhood abdominal circumference and weight gain with blood pressure at 36 months of age: secondary analysis of data from a prospective cohort study

To assess whether changes in measures of fat distribution and body size during early life are associated with blood pressure at 36 months of age.

Analysis of 177Lu-octreotate therapy-induced DNA damage in peripheral blood lymphocytes of patients with neuroendocrine tumors

Ionizing radiation (IR)-induced DNA double-strand breaks (DSBs) can lead to cell death, genome instability and carcinogenesis. Immunofluorescence detection of phosphorylated histone variant H2AX (γ-H2AX) is a reliable and sensitive technique to monitor external beam IR-induced DSBs in peripheral blood lymphocytes (PBL). Here, we investigated whether γ-H2AX could be used as an in vivo marker to assess normal tissue toxicity after extended internal irradiation with (177)Lu-DOTA-octreotate peptide receptor radionuclide therapy (LuTate PRRT) of neuroendocrine tumors.

Analysis and prediction of major blood proteins based on their amino acid and dipeptide composition

A method has been developed for predicting blood proteins using the SVM based machine learning approach. In this prediction method a two-step strategy was deployed to predict blood proteins and their subclasses. We have developed models of blood proteins and achieved the maximum accuracies of 90.57% and 91.39% with Matthews correlation coefficient (MCC) of 0.89 and 0.90 using single amino acid and dipeptide composition respectively. Furthermore, the method is able to predict major subclasses of blood proteins; developed based on amino acid (AC) and dipeptide composition (DC) with a maximum accuracy 90.38%, 92.83%, 87.41%, 92.52% and 85.27%, 89.07%, 94.82%, 86.31 for albumin, globulin, fibrinogen, and regulatory proteins respectively. All modules were trained, tested, and evaluated using the five-fold cross-validation technique.

A pilot assessment of alpha-stat vs pH-stat arterial blood gas analysis after cardiac arrest

PURPOSE: Resuscitated cardiac arrest (CA) patients typically receive therapeutic hypothermia, but arterial blood gases (ABGs) are often assessed after adjustment to 37°C (alpha-stat) instead of actual body temperature (pH-stat). We sought to compare alpha-stat and pH-stat assessment of PaO2 and PaCO2 in such patients. MATERIALS AND METHODS: Using ABG data obtained during the first 24 hours of intensive care unit admission, we determined the impact of measured alpha vs calculated pH-stat on PaO2 and PaCO2 on patient classification and outcomes for CA patients. RESULTS: We assessed 1013 ABGs from 120 CA patients with a median age of patients 66 years (interquartile range, 50-76). Median alpha-stat PaO2 changed from 122 (95-156) to 107 (82-143) mm Hg with pH-stat and median PaCO2 from 39 (34-46) to 35 (30-41) mm Hg (both P < .001). Using the categories of hyperoxemia, normoxemia, and hypoxemia, pH-stat estimation of PaO2 reclassified approximately 20% of patients. Using the categories of hypercapnia, normocapnia, and hypocapnia, pH stat estimation of PaCO2 reclassified approximately 40% of patients. The mortality of patients in different PaO2 and PaCO2 categories was similar for pH-stat and alpha-stat. CONCLUSIONS: Using the pH-stat method, fewer resuscitated CA patients admitted to intensive care unit were classified as hyperoxemic or hypercapnic compared with alpha-stat. These findings suggest an impact of ABG assessment methodology on PaO2, PaCO2 , and patient classification but not on associated outcomes.

Association of birth weight and current body size to blood pressure in female twins

It has been proposed that low birth weight is associated with high levels of blood pressure in later life. The aim of this study was to assess the relationship of blood pressure to birth weight and current body size during growth and adulthood. A total of 711 female multiple births, with one group of 244 in their growth phase mean age 12.0 (2.3)(SD) years and the other of 467 adults (mean age 35.2 (12.6) years), had height, weight and both systolic (SBP) and diastolic (DBP) blood pressures measured, and self-reported their birth weight. Regression analyses were performed to assess the cross-sectional and within-pair associations of blood pressure to birth weight, with and without adjustments for current body size. Within-pair analysis was based on 296 twin pairs. Cross-sectionally, a reduction in birth weight of 1 kg was associated with 2 to 3 mm Hg higher age-adjusted SBP, which was of marginal significance and explained about 2% of the population variance. Adjustment for body mass index did not significantly change this association. Within-pair analyses found no association between birth weight and SBP or DBP,even after adjusting for current body size. After age, current body size was the strongest predictor of systolic BP. The weak association of blood pressure to birth weight cross-sectionally is of interest, but any within-pair effect of birth weight on blood pressure must be minimal compared with the effect of current body size.

Functional analysis of natriuretic peptide receptors in the bladder of the toad, bufo marinus

This study aimed to localize and characterize natriuretic peptide binding sites in the urinary bladder of Bufo marinus and to then examine the effect of natriuretic peptides on the bladder vascular tone and water reabsorption in isolated perfused bladder preparations. Specific ¹²⁵I-rat atrial natriuretic peptide (¹²⁵I-rANP) binding sites were present on blood vessels, muscle, and epithelium. In tissue sections and/or isolated membranes, the binding was completely displaced by frog ANP, rat ANP, and porcine C-type natriuretic peptide (CNP; membranes only). However, a reduction in binding was observed after incubation with ¹²⁵I-rANP and 1 μM of the natriuretic peptide receptor-C (NPR-C) ligand C-ANF, but residual binding remained suggesting the presence of two distinct binding sites. Electrophoresis of bladder membranes cross-linked to ¹²⁵I-rANP identified two bands at approximately 70 and 140 kDa that correspond to the monomeric mass of NPR-C and the guanylate cyclase receptors, respectively. Furthermore, the presence of natriuretic peptide receptor-A and NPR-C mRNA in the bladder was demonstrated with reverse transcription–polymerase chain reaction. In addition, rat ANP, frog ANP, and porcine CNP stimulated a significant increase in cGMP generation in bladder membrane preparations, which indicated the presence of guanylate cyclase-linked receptors. In perfused bladder preparations, arginine vasotocin increased perfusion pressure and water permeability. The infusion of frog ANP or porcine CNP failed to alter perfusion pressure or water reabsorption in the presence or absence of arginine vasotocin. This study identified a well-developed natriuretic peptide receptor system in the urinary bladder of B. marinus but the function of the receptors remains unclear.