Effect of mobile telephony on blood-brain barrier permeability in the fetal mouse brain

AIMS: To study the effect of mobile telephone exposure on blood-brain barrier (BBB) permeability in the immature brain. METHODS: Using a purpose-designed exposure system at 900 MHz, pregnant mice were given a single, far-field, whole body exposure at a specific absorption rate of 4 W/kg for 60 min/day from day 1 to day 19 of gestation. Pregnant control mice were sham-exposed or freely mobile in a cage without further restraint and a positive control group with cadmium-induced BBB damage was also included. Immediately prior to parturition on gestational day 19, fetal heads were collected, fixed in Bouin's fixative and paraffin embedded. Disruption of BBB integrity was detected immunohistochemically using endogenous albumin as a vascular tracer in cerebral cortex, thalamus, basal ganglia, hippocampus, cerebellum, midbrain and medulla. RESULTS: No albumin extravasation was found in exposed or control brains. CONCLUSION: In this animal model, whole of gestation exposure to global system for mobile communication-like radiofrequency fields did not produce any increase in vascular permeability in the fetal brain regions studied using endogenous albumin as a light microscopic immunohistochemical marker.     

Mutations in rpoB gene and rifabutin susceptibility of multidrug-resistant Mycobacterium tuberculosis strains isolated in Australia.

Control of tuberculosis, the single largest killer among the infectious diseases, has been threatened by the emergence of multidrug-resistant Mycobacterium tuberculosis (MDRTB) infection due to the limited treatment options. Rifampicin (RIF) resistance is considered as a marker for MDRTB. The aim of this study was the detection of rpoB gene mutations and rifabutin resistance in MDRTB strains recently isolated in Australia by a line probe assay (INNO-LiPA Rif. TB, Innogenetics). Rifabutin and RIF susceptibility of 20 MDRTB and 16 RIF-sensitive M. tuberculosis complex clinical isolates were studied. The overall concordance of the line probe assay (LiPA) with phenotypic RIF susceptibility test was 96%. Seven distinct nucleotide substitutions were identified in 21 of 22 RIF-resistant isolates of diverse geographical origins, but in none of the RIF-sensitive strains. The majority (71%) of mutations occurred in the 526-533 codons and were associated with resistance to rifabutin and RIF. Of the RIF-resistant MDRTB strains, 18% appeared to be rifabutin-sensitive and produced delta S2 and delta S3 INNO-LiPA patterns. We conclude that amino acid substitutions at Asp516 and Ser522 in the rpoB gene in RIF-resistant M. tuberculosis predict rifabutin susceptibility for MDRTB. Use of the LiPA for RIF and rifabutin resistance may facilitate the rapid response required to limit the extent and severity of MDRTB transmission and infection.     

Cytotoxicity evaluation and antioxidant enzyme expression related to heavy metals found in tuna by-products meal: An in vitro study in human and rat liver cell lines

Heavy metals can accumulate in organisms via various pathways, including respiration, adsorption and ingestion. They are known to generate free radicals and induce oxidative and/or nitrosative stress with depletion of anti-oxidants. Tuna by-product meal (TBM) is rich in proteins and can, therefore, offer an attractive protein source for animals. This study was undertaken to assess the effects of metals present in TBM, namely cadmium (Cd), lead (Pb), and mercury (Hg), separately or in combination with oxidative stress, on cell viability. Three cell models: rat liver FTO2B, human hepatoma HepG2, and human hepatic WRL-68, were used. Cell viability was determined following exposure to various concentrations of the metals. Two antioxidant genes, catalase (CAT) and superoxide dismutase (SOD), were measured to obtain a better understanding of oxidative stress-associated gene expression. Among the metals present in TBM, only Cd at a concentration of 30 μM was noted to exhibit cytotoxic effects. This cytotoxicity was even more pronounced after co-stimulation with H₂O₂, used to mimic systemic oxidative stress. At non-toxic concentrations, Hg and Pb were noted to aggravate oxidative stress toxicity. The results further revealed that exposure to Cd, Pb, and a co-stimulation of H₂O₂ with Hg resulted in the increased expression of antioxidant gene SOD. A risk assessment of toxic contaminants in TBM indicated that food safety objectives should consider the human health impacts of foods derived from animals fed on contaminated meal and that much care should be taken when TBM is used in animal diet.     

Distribution of methionine-enkephalin in the minipig brainstem

We have studied the distribution of immunoreactive cell bodies and axons are containing methionine-enkephalin in the minipig brainstem. Immunoreactive axons were widely distributed, whereas the distribution of perikarya was less widespread. A high or moderate density of axons containing methionine-enkephalin were found from rostral to caudal levels in the substantia nigra, nucleus interpeduncularis, nucleus reticularis tegmenti pontis, nucleus dorsalis raphae, nucleus centralis raphae, nuclei dorsalis and ventralis tegmenti of Gudden, locus ceruleus, nucleus sensorius principalis nervi trigemini, nucleus cuneatus externalis, nucleus tractus solitarius, nuclei vestibularis inferior and medialis, nucleus ambiguus, nucleus olivaris inferior and in the nucleus tractus spinalis nervi trigemini. Immunoreactive perikarya were observed in the nuclei centralis and dorsalis raphae, nucleus motorius nervi trigemini, nucleus centralis superior, nucleus nervi facialis, nuclei parabrachialis medialis and lateralis, nucleus ventralis raphae, nucleus reticularis lateralis and in the formatio reticularis. We have also described the presence of perikarya containing methionine-enkephalin in the nuclei nervi abducens, ruber, nervi oculomotorius and nervi trochlearis. These results suggest that in the minipig the pentapeptide may be involved in many physiological functions (for example, proprioceptive and nociceptive information; motor, respiratory and cardiovascular mechanisms).     

The use of coroner's autopsy reports to validate the use of targeted swabbing rather than tissue collection for rapid confirmation of virological causes of sudden death in the community

Background and objectivesIn this study, coroner's autopsy reports were used to validate results obtained from respiratory virus screening of swabs rather than tissue collected during autopsy in cases of adult death of unknown cause.Study designCoroner's autopsy samples collected for respiratory virus screening between October 2010 and February 2011, were identified. Autopsy reports were requested from cases positive for a virus. Each report was reviewed to correlate findings at autopsy with the virology result and to determine whether the virus found was listed as a contributing factor in the death.ResultsSixty-four coroner's autopsy cases were identified and a respiratory virus was found in 25 cases. Influenza A(H1N1)pdm09 virus was found most frequently, then RSV and influenza B with a dual influenza A and B infection and a parainfluenza type 1. Where multiple sites were swabbed, the virus was detected in all sites. Autopsy reports for 12 cases were obtained each reporting findings consistent with respiratory infection. Influenza A was always listed as a contributing factor in the death whereas RSV was listed once and influenza B was omitted in one case. The quality of the reports was variable and full histology was less likely to be performed in the elderly.ConclusionsWhile coroner's reports supported the use of swabbing rather than tissue collection, the lack of consistency and omission of the virology findings as contributing factors to death means that the burden of viruses on mortality statistics will remain under-estimated particularly in the elderly.     

Prostate cancer: the new evidence base for diagnosis and treatment

Although prostate cancer (PC) has a significant mortality, there is debate regarding the utility of PC screening. This debate continues as major studies investigating the value of population-based screening have yet to be concluded. Despite this, there is increasing evidence from preliminary reports from these series, as well as numerous others relating to outcome prediction for PC, that early detection leads to improved outcomes and a decrease in the burden of metastatic disease on our healthcare system. PC is rarely symptomatic until it has metastasised to bone and because of this PSA-based screening remains the only widely available and reliable method of diagnosis for organ-confined disease. There is now compelling evidence to show that: 1. Cancers diagnosed by screening are more likely to be early stage, when most can be cured by a number of different treatment options. 2. The maximum benefits of screening are for men aged 50-70 years. Older men have a greater chance of a clinically insignificant cancer being diagnosed for which treatment is not necessary. 3. The familial risks of PC are well recognised. In particular, men with one or more first-degree relatives already diagnosed with the disease should be actively encouraged to undergo screening. 4. Modern histopathological assessment of fine core needle biopsies of the prostate allows for the likely behaviour of cancer present to be accurately predicted. Changes that mimic those of malignancy can be confidently identified, so these cases are no longer incorrectly diagnosed. These improvements mean that now most men aged 50-70 years diagnosed with PC will have clinically significant cancers that require treatment.     

Molecular biomarkers in malignant mesothelioma: state of the art

Malignant mesothelioma (MM) is an aggressive tumour affecting the mesothelial surfaces of the pleural and peritoneal cavities and, rarely, the pericardium and the tunica vaginalis testis. Despite a ban of asbestos in many industrialised nations, the present high incidence of MM is expected to continue, due to the long latency period between first asbestos exposure and occurrence of disease, making it an important health issue for the future. The diagnosis of MM can be difficult, both from a clinical and pathological perspective. It is not unusual for patients to undergo several medical investigations without definitive diagnosis early in their course of illness. Understandably, there is intense interest in the discovery of markers that can be assessed in pleural effusions, histological specimens, and serum to assist with the difficult early diagnosis of MM. Considering the primary aetiological role of asbestos, there is theoretically an easily identifiable target population for screening with a biomarker with adequate sensitivity and specificity or with a combination of biomarkers. In this review we focus on biomarkers that have been examined in the setting of either early diagnosis of MM in symptomatic patients or screening of asbestos-exposed individuals.     

Epidemiology of respiratory viruses in bronchoalveolar lavage samples in a tertiary hospital

BackgroundThe prevalence of respiratory viruses in adults is largely underexplored, as most studies focus on children. Additionally, in severely ill or immunocompromised adults, where respiratory infections are mostly attributed to bacteria and fungi; respiratory viruses can lead to severe complications.ObjectivesTo evaluate the epidemiology of respiratory viruses in bronchoalveolar lavage fluid (BAL) specimens from patients with lower respiratory tract disease. The study population consisted of different groups including immunocompetent patients (control patients), solid organ transplant recipients, patients with haematological malignancies and other immunocompromised adults.Study designA total of 134 BAL fluid specimens collected during 2009–2011 were retrospectively assessed with the new commercial multiplex real-time PCR FTD Respiratory 21 Plus^®, targeting 18 different viruses and 2 atypical bacterial pathogens.ResultsViral or atypical bacterial pathogens were detected in 29.1% of BAL fluid specimens. Coronaviruses were most prevalent (13.4%), followed by rhinoviruses (5.2%), RSV (4.5%) and bocaviruses (3.7%). Comparing the total number of viruses detected, a statistically significant difference was observed between the control group and patients with haematological malignancies (27.5% vs. 57.1%, p < 0.05).ConclusionIn conclusion, our study highlights the high prevalence of respiratory viruses in BAL fluid specimens from adult patients with lower respiratory tract disease. The methods to be used should be sensitive and cover a wide range of potential pathogens. The specific patient population can also influence the detection rates of respiratory viruses.     

Localization of Na+–K+-ATPase α/β, Na+–K+–2Cl-cotransporter 1 and aquaporin-5 in human eccrine sweat glands

In order to evaluate the function of the repaired or regenerated eccrine sweat glands, we must first localize the proteins involved in sweat secretion and absorption in normal human eccrine sweat glands. In our studies, the cellular localization of Na⁺–K⁺-ATPase α/β, Na⁺–K⁺–2Cl-cotransporter 1 (NKCC1) and aquaporin-5 (AQP5) in eccrine sweat glands were detected by immunoperoxidase labeling. The results showed that Na⁺–K⁺-ATPase α was immunolocalized in the cell membrane of the basal layer and suprabasal layer cells of the epidermis, the basolateral membrane of the secretory coils, and the cell membrane of the outer cells and the basolateral membrane of the luminal cells of the ducts. The localization of Na⁺–K⁺-ATPase β in the secretory coils was the same as Na⁺–K⁺-ATPase α, but Na⁺–K⁺-ATPase β labeling was absent in the straight ducts and epidermis. NKCC1 labeling was seen only in the basolateral membrane of the secretory coils. AQP5 was strongly localized in the apical membrane and weakly localized in the cytoplasm of secretory epithelial cells. The different distribution of these proteins in eccrine sweat glands was related to their functions in sweat secretion and absorption.     

Histological studies of neuroprotective effects of Curcuma longa Linn. on neuronal loss induced by dexamethasone treatment in the rat hippocampus

Long term exposure to dexamethasone (Dx) is associated with brain damage especially in the hippocampus via the oxidative stress pathway. Previously, an ethanolic extract from Curcuma longa Linn. (CL) containing the curcumin constituent has been reported to produce antioxidant effects. However, its neuroprotective property on brain histology has remained unexplored. This study has examined the effects of a CL extract on the densities of cresyl violet positive neurons and glial fibrillary acidic protein immunoreactive (GFAP-ir) astrocytes in the hippocampus of Dx treated male rats. It showed that 21days of Dx treatment (0.5 mg/kg, i.p. once daily) significantly reduced the densities of cresyl violet positive neurons in the sub-areas CA1, CA3 and the dentate gyrus, but not in the CA2 area. However, CL pretreatment (100 mg/kg, p.o.) was found to significantly restore neuronal densities in the CA1 and dentate gyrus. In addition, Dx treatment also significantly decreased the densities of the GFAP-ir astrocytes in the sub-areas CA1, CA3 and the dentate gyrus. However, CL pretreatment (100 mg/kg, p.o.) failed to protect the loss of astrocytes in these sub-areas. These findings confirm the neuroprotective effects of the CL extract and indicate that the cause of astrocyte loss might be partially reduced by a non-oxidative mechanism. Moreover, the detection of neuronal and glial densities was suitable method to study brain damage and the effects of treatment.     

The centrally projecting Edinger–Westphal nucleus—I: Efferents in the rat brain

The oculomotor accessory nucleus, often referred to as the Edinger–Westphal nucleus [EW], was first identified in the 17th century. Although its most well known function is the control of pupil diameter, some controversy has arisen regarding the exact location of these preganglionic neurons. Currently, the EW is thought to consist of two different parts. The first part [termed the preganglionic EW—EWpg], which controls lens accommodation, choroidal blood flow and pupillary constriction, primarily consists of cholinergic cells that project to the ciliary ganglion. The second part [termed the centrally projecting EW—EWcp], which is involved in non-ocular functions such as feeding behavior, stress responses, addiction and pain, consists of peptidergic neurons that project to the brainstem, the spinal cord and prosencephalic regions. However, in the literature, we found few reports related to either ascending or descending projections from the EWcp that are compatible with its currently described functions. Therefore, the objective of the present study was to systematically investigate the ascending and descending projections of the EW in the rat brain. We injected the anterograde tracer biotinylated dextran amine into the EW or the retrograde tracer cholera toxin subunit B into multiple EW targets as controls. Additionally, we investigated the potential EW-mediated innervation of neuronal populations with known neurochemical signatures, such as melanin-concentrating hormone in the lateral hypothalamic area [LHA] and corticotropin-releasing factor in the central nucleus of the amygdala [CeM]. We observed anterogradely labeled fibers in the LHA, the reuniens thalamic nucleus, the oval part of the bed nucleus of the stria terminalis, the medial part of the central nucleus of the amygdala, and the zona incerta. We confirmed our EW–LHA and EW–CeM connections using retrograde tracers. We also observed moderate EW-mediated innervation of the paraventricular nucleus of the hypothalamus and the posterior hypothalamus. Our findings provide anatomical bases for previously unrecognized roles of the EW in the modulation of several physiologic systems.     

Broadsheet. Number 50: Diagnosis of human cytomegalovirus infection and disease.

Human cytomegalovirus (CMV) remains an important cause of illness in immunocompromised individuals and the most common viral cause of congenital malformation. The tests available for diagnosis of CMV include serology, antigen detection, virus culture, tissue histopathology and nucleic acid detection. The diagnosis of CMV remains difficult because of the issues of virus latency, virus infection versus clinical disease and virus reactivation. The tests available and the use of these tests are undergoing significant changes. This Broadsheet presents a review of these tests, particularly in the diagnosis of congenital infection and infection in pregnant women and immunocompromised individuals.     

Effect of low estrogen on neurons in the preoptic area of hypothalamus of ovariectomized rats

The purpose of this study was to investigate the difference in neuronal activity in the preoptic area of the hypothalamus (POAH) under low estrogen condition induced by ovariectomy. One hundred and twenty sham-operated (SHAM) and ovariectomized (OVX) rats were placed in different temperatures for 2 h. Twelve rats from each group were stimulated by 4 °C, 10 °C, 25 °C, 33 °C and 38 °C, respectively. c-Fos expression in the POAH was detected by immunohistochemistry. Following exposure to warm and cold stimuli, there were markedly lower c-Fos-positive cell densities in the OVX group compared with the SHAM group in the median preoptic nucleus (MnPO) at 4 °C, 10 °C, 33 °C and 38 °C, in the medial preoptic area (MPA) at 25 °C and 38 °C, in the ventromedial preoptic nucleus (VMPO) at 4 °C, 10 °C and 38 °C and in the ventrolateral preoptic nucleus (VLPO) at 4 °C and 38 °C. Both temperature and surgery had an impact on c-Fos expression by two-way ANOVA method except in the lateral preoptic area (LPO). c-Fos expression differed within different nuclei of the two groups in the same and different temperature stimuli. This indicated that the temperature-sensitive nuclei in the POAH exhibited lower and different activities during temperature stimuli following ovariectomy, which possibly resulted in abnormal thermoregulation and menopausal symptoms.     

Subcellular localization and activation of ADAM proteases in the context of FasL shedding in T lymphocytes

The “A Disintegrin And Metalloproteinases” (ADAMs) form a subgroup of the metzincin endopeptidases. Proteolytically active members of this protein family act as sheddases and govern key processes in development and inflammation by regulating cell surface expression and release of cytokines, growth factors, adhesion molecules and their receptors. In T lymphocytes, ADAM10 sheds the death factor Fas Ligand (FasL) and thereby regulates T cell activation, death and effector function. Although FasL shedding by ADAM10 was confirmed in several studies, its regulation is still poorly defined. We recently reported that ADAM10 is highly abundant on T cells whereas its close relative ADAM17 is expressed at low levels and transiently appears at the cell surface upon stimulation. Since FasL is also stored intracellularly and brought to the plasma membrane upon stimulation, we addressed where the death factor gets exposed to ADAM proteases. We report for the first time that both ADAM10 and ADAM17 are associated with FasL-containing secretory lysosomes. Moreover, we demonstrate that TCR/CD3/CD28-stimulation induces a partial positioning of both proteases and FasL to lipid rafts and only the activation-induced raft-positioning results in FasL processing. TCR/CD3/CD28-induced FasL proteolysis is markedly affected by reducing both ADAM10 and ADAM17 protein levels, indicating that in human T cells also ADAM17 is implicated in FasL processing. Since FasL shedding is affected by cholesterol depletion and by inhibition of Src kinases or palmitoylation, we conclude that it requires mobilization and co-positioning of ADAM proteases in lipid raft-like platforms associated with an activation of raft-associated Src-family kinases.     

TRARESA: a tissue microarray-based hospital system for biomarker validation and discovery

Formalin fixed and paraffin embedded tissue (FFPE) collections in pathology departments are the largest resource for retrospective biomedical research studies. Based on the literature analysis of FFPE related research, as well as our own technical validation, we present the Translational Research Arrays (TRARESA), a tissue microarray centred, hospital based, translational research conceptual framework for both validation and/or discovery of novel biomarkers. TRARESA incorporates the analysis of protein, DNA and RNA in the same samples, correlating with clinical and pathological parameters from each case, and allowing (a) the confirmation of new biomarkers, disease hypotheses and drug targets, and (b) the postulation of novel hypotheses on disease mechanisms and drug targets based on known biomarkers. While presenting TRARESA, we illustrate the use of such a comprehensive approach. The conceptualisation of the role of FFPE-based studies in translational research allows the utilisation of this commodity, and adds to the hypothesis-generating armamentarium of existing high-throughput technologies.     

Nuclear organization of some immunohistochemically identifiable neural systems in two species of the Euarchontoglires: A Lagomorph,Lepus capensis,and a Scandentia,Tupaia belangeri

The present study describes the organization of the nuclei of the cholinergic, catecholaminergic, serotonergic and orexinergic systems in the brains of two members of Euarchontoglires, Lepus capensis and Tupaia belangeri. The aim of the present study was to investigate the nuclear complement of these neural systems in comparison to previous studies on Euarchontoglires and generally with other mammalian species. Brains were coronally sectioned and immunohistochemically stained with antibodies against choline acetyltransferase, tyrosine hydroxylase, serotonin and orexin-A. The majority of nuclei revealed in the current study were similar between the species investigated and to mammals generally, but certain differences in the nuclear complement highlight potential phylogenetic interrelationships within the Euarchontoglires and across mammals. In the northern tree shrew the nucleus of the trapezoid body contained neurons immunoreactive to the choline acetyltransferase antibody with some of these neurons extending into the lamellae within the superior olivary nuclear complex (SON). The cholinergic nature of the neurons of this nucleus, and the extension of cholinergic neurons into the SON, has not been noted in any mammal studied to date. In addition, cholinergic neurons forming the medullary tegmental field were also present in the northern tree shrew. Regarding the catecholaminergic system, the cape hare presented with the rodent specific rostral dorsal midline medullary nucleus (C3), and the northern tree shrew lacked both the ventral and dorsal divisions of the anterior hypothalamic group (A15v and A15d). Both species were lacking the primate/megachiropteran specific compact portion of the locus coeruleus complex (A6c). The nuclei of the serotonergic and orexinergic systems of both species were similar to those seen across most Eutherian mammals. Our results lend support to the monophyly of the Glires, and more broadly suggest that the megachiropterans are more closely related to the primates than are any other members of Euarchontoglires studied to date.     

A combined acetylcholinesterase and immunohistochemical method for precise anatomical analysis of intrinsic cardiac neural structures

A significant challenge when investigating autonomic neuroanatomy is being able to reliably obtain tissue that contains neuronal structures of interest. Currently, histochemical staining for acetylcholinesterase (AChE) remains the most feasible and reliable method to visualize intrinsic nerves and ganglia in whole organs. In order to precisely visualize and sample intrinsic cardiac nerves and ganglia for subsequent immunofluorescent labeling, we developed a modified histochemical AChE method using material from pig and sheep hearts. The method involves: (1) chemical prefixation of the whole heart, (2) short-term and weak histochemical staining for AChE in situ, (3) visual examination and extirpation of the stained neural structures from the whole heart, (4) freezing, embedding and cryostat sectioning of the tissue of interest, and (5) immunofluorescent labeling and microscopic analysis of neural structures. Firstly, our data demonstrate that this modified AChE protocol labeled intrinsic cardiac nerves as convincingly as our previously published data. Secondly, there was the added advantage that adrenergic, cholinergic and peptidergic neuropeptides, namely protein gene product 9.5 (PGP 9.5), neurofilament (NF), tyrosine hydroxylase (TH), vesicular monoamine transporter (VMAT2), neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), calcitonin gene related peptide (CGRP), and substance P may be identified. Our method allows the precise sampling of neural structures including autonomic ganglia, intrinsic nerves and bundles of nerve fibers and even single neurons from the whole heart. This method saves time, effort and a substantial amount of antisera. Nonetheless, the proof of specific staining for many other autonomic neuronal markers has to be provided in subsequent studies.     

Complex phenotypes in the haemoglobinopathies: recommendations on screening and DNA testing

This document considers a number of scenarios involving complex haemoglobinopathies and provides 28 recommendations at both the clinical and laboratory levels on how these should be managed.