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1.
Acta Vet Scand ; 64(1): 23, 2022 Sep 06.
Article in English | MEDLINE | ID: mdl-36068608

ABSTRACT

BACKGROUND: Hypohidrotic ectodermal dysplasia (HED) is a congenital syndrome of mammals affecting organs and tissues of ectodermal origin characterized by absence or hypoplasia of hair, teeth, and eccrine glands. The disorder has been reported in several species, including humans, mice, dogs and cattle, associated with variants in genes affecting the ectodysplasin pathway, including the X-linked ectodysplasin A (EDA) gene. Until now, nine pathogenic variants have been found in the bovine EDA gene. Here we report a novel variant in EDA in a crossbreed male Belgian Blue calf with HED, and provide an overview of the phenotypic and allelic heterogeneity of EDA-related forms of HED in cattle. CASE PRESENTATION: A 45-day-old male crossbreed British Blue calf was referred with congenital hypotrichosis, oligodontia and omphalitis. On histopathological examination of the nasal planum, nasolabial glands and ducts were not observed. The density of hair follicles was low, and they were small, with a predominance of telogen-phase hairs, and some serocellular crusts. The phenotype of the calf resembled that of HED. Whole-genome sequencing (WGS) was performed and revealed a 21,899 base-pair deletion encompassing the coding exon 2 of EDA, predicted to result in an altered transcript and aberrant protein. CONCLUSIONS: The clinicopathological and genetic findings were consistent with a case of X-linked HED. A very similar EDA deletion has been previously reported in a family of Holstein cattle with HED. The newly identified hemizygous EDA loss-of-function variant is certainly pathogenic and therefore is the genetic cause for the observed phenotype. This case report provides an additional example of the potential of WGS-based precise diagnostics in livestock species such as cattle to increase the diagnostic yield in rare diseases.


Subject(s)
Cattle Diseases , Ectodermal Dysplasia 1, Anhidrotic , Ectodermal Dysplasia , Animals , Cattle , Cattle Diseases/genetics , Ectodermal Dysplasia/genetics , Ectodermal Dysplasia/veterinary , Ectodermal Dysplasia 1, Anhidrotic/genetics , Ectodermal Dysplasia 1, Anhidrotic/pathology , Ectodermal Dysplasia 1, Anhidrotic/veterinary , Ectodysplasins/genetics , Exons , Male , Phenotype
2.
Sci Rep ; 12(1): 11669, 2022 07 08.
Article in English | MEDLINE | ID: mdl-35803982

ABSTRACT

Livestock abortion is an important cause of productivity losses worldwide and many infectious causes of abortion are zoonotic pathogens that impact on human health. Little is known about the relative importance of infectious causes of livestock abortion in Africa, including in subsistence farming communities that are critically dependent on livestock for food, income, and wellbeing. We conducted a prospective cohort study of livestock abortion, supported by cross-sectional serosurveillance, to determine aetiologies of livestock abortions in livestock in Tanzania. This approach generated several important findings including detection of a Rift Valley fever virus outbreak in cattle; high prevalence of C. burnetii infection in livestock; and the first report of Neospora caninum, Toxoplasma gondii, and pestiviruses associated with livestock abortion in Tanzania. Our approach provides a model for abortion surveillance in resource-limited settings. Our findings add substantially to current knowledge in sub-Saharan Africa, providing important evidence from which to prioritise disease interventions.


Subject(s)
Abortion, Veterinary , Cattle Diseases , Rift Valley Fever , Abortion, Veterinary/epidemiology , Abortion, Veterinary/etiology , Animals , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/etiology , Cross-Sectional Studies , Female , Humans , Livestock , Pregnancy , Prospective Studies , Rift Valley Fever/epidemiology , Seroepidemiologic Studies , Tanzania/epidemiology
3.
Parasit Vectors ; 13(1): 413, 2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32787904

ABSTRACT

BACKGROUND: There has been no evidence of transmission of mosquito-borne arboviruses of equine or human health concern to date in the UK. However, in recent years there have been a number of outbreaks of viral diseases spread by vectors in Europe. These events, in conjunction with increasing rates of globalisation and climate change, have led to concern over the future risk of mosquito-borne viral disease outbreaks in northern Europe and have highlighted the importance of being prepared for potential disease outbreaks. Here we assess several UK mosquito species for their potential to transmit arboviruses important for both equine and human health, as measured by the presence of viral RNA in saliva at different time points after taking an infective blood meal. RESULTS: The following wild-caught British mosquitoes were evaluated for their potential as vectors of zoonotic equine arboviruses: Ochlerotatus detritus for Venezuelan equine encephalitis virus (VEEV) and Ross River virus (RRV), and Culiseta annulata and Culex pipiens for Japanese encephalitis virus (JEV). Production of RNA in saliva was demonstrated at varying efficiencies for all mosquito-virus pairs. Ochlerotatus detritus was more permissive for production of RRV RNA in saliva than VEEV RNA. For RRV, 27.3% of mosquitoes expectorated viral RNA at 7 days post-infection when incubated at 21 °C and 50% at 24 °C. Strikingly, 72% of Cx. pipiens produced JEV RNA in saliva after 21 days at 18 °C. For some mosquito-virus pairs, infection and salivary RNA titres reduced over time, suggesting unstable infection dynamics. CONCLUSIONS: This study adds to the number of Palaearctic mosquito species that demonstrate expectoration of viral RNA, for arboviruses of importance to human and equine health. This work adds to evidence that native mosquito species should be investigated further for their potential to vector zoonotic mosquito-borne arboviral disease of equines in northern Europe. The evidence that Cx. pipiens is potentially an efficient laboratory vector of JEV at temperatures as low as 18 °C warrants further investigation, as this mosquito is abundant in cooler regions of Europe and is considered an important vector for West Nile Virus, which has a comparable transmission ecology.


Subject(s)
Arbovirus Infections/veterinary , Arboviruses/isolation & purification , Mosquito Vectors/virology , Aedes/virology , Animals , Arbovirus Infections/transmission , Culex/virology , Encephalitis Virus, Japanese/isolation & purification , Encephalitis Virus, Venezuelan Equine/isolation & purification , Horse Diseases/transmission , Horse Diseases/virology , Horses , Humans , Ochlerotatus/virology , Pathology, Molecular , RNA, Viral/analysis , Ross River virus/isolation & purification , Saliva/virology , United Kingdom/epidemiology , West Nile Fever/transmission , Zoonoses/transmission , Zoonoses/virology
4.
Proc Biol Sci ; 287(1930): 20200119, 2020 07 08.
Article in English | MEDLINE | ID: mdl-32635867

ABSTRACT

Mosquito-borne Zika virus (ZIKV) transmission has almost exclusively been detected in the tropics despite the distributions of its primary vectors extending farther into temperate regions. Therefore, it is unknown whether ZIKV's range has reached a temperature-dependent limit, or if it can spread into temperate climates. Using field-collected mosquitoes for biological relevance, we found that two common temperate mosquito species, Aedes albopictus and Ochlerotatus detritus, were competent for ZIKV. We orally exposed mosquitoes to ZIKV and held them at between 17 and 31°C, estimated the time required for mosquitoes to become infectious, and applied these data to a ZIKV spatial risk model. We identified a minimum temperature threshold for the transmission of ZIKV by mosquitoes between 17 and 19°C. Using these data, we generated standardized basic reproduction number R0-based risk maps and we derived estimates for the length of the transmission season for recent and future climate conditions. Our standardized R0-based risk maps show potential risk of ZIKV transmission beyond the current observed range in southern USA, southern China and southern European countries. Transmission risk is simulated to increase over southern and Eastern Europe, northern USA and temperate regions of Asia (northern China, southern Japan) in future climate scenarios.


Subject(s)
Mosquito Vectors , Temperature , Zika Virus Infection/transmission , Aedes , Animals , Basic Reproduction Number , Climate , Zika Virus
5.
Vet Rec ; 183(5): 159, 2018 08 04.
Article in English | MEDLINE | ID: mdl-29764954

ABSTRACT

Increased globalisation and climate change have led to concern about the increasing risk of arthropod-borne virus (arbovirus) outbreaks globally. An outbreak of equine arboviral disease in northern Europe could impact significantly on equine welfare, and result in economic losses. Early identification of arboviral disease by horse owners may help limit disease spread. In order to determine what horse owners understand about arboviral diseases of horses and their vectors, the authors undertook an open, cross-sectional online survey of UK horse owners. The questionnaire was distributed using social media and a press release and was active between May and July 2016. There were 466 respondents, of whom 327 completed the survey in full. High proportions of respondents correctly identified photographic images of biting midges (71.2 per cent) and mosquitoes (65.4 per cent), yet few were aware that they transmit equine infectious diseases (31.4 per cent and 35.9 per cent, respectively). Of the total number of respondents, only 7.4 per cent and 16.2 per cent correctly named a disease transmitted by biting midges and mosquitoes, respectively. Only 13.1 per cent and 12.5 per cent of participants identified specific clinical signs of African horse sickness (AHS) and West Nile virus (WNV), respectively. This study demonstrates that in the event of heightened disease risk educational campaigns directed towards horse owners need to be implemented, focussing on disease awareness, clinical signs and effective disease prevention strategies.


Subject(s)
Arbovirus Infections/veterinary , Arboviruses , Disease Vectors , Health Knowledge, Attitudes, Practice , Horse Diseases/virology , Ownership , Adult , Animals , Arbovirus Infections/epidemiology , Arbovirus Infections/prevention & control , Arbovirus Infections/virology , Cross-Sectional Studies , Disease Outbreaks/prevention & control , Disease Outbreaks/veterinary , Female , Horse Diseases/epidemiology , Horse Diseases/prevention & control , Horses , Humans , Insect Bites and Stings/prevention & control , Insect Vectors/virology , Male , Middle Aged , United Kingdom/epidemiology
6.
Parasit Vectors ; 9: 452, 2016 08 15.
Article in English | MEDLINE | ID: mdl-27527700

ABSTRACT

BACKGROUND: To date there has been no evidence of mosquito-borne virus transmission of public health concern in the UK, despite the occurrence of more than 30 species of mosquito, including putative vectors of arboviruses. The saltmarsh mosquito Ochlerotatus detritus [syn. Aedes (Ochlerotatus) detritus] is locally common in parts of the UK where it can be a voracious feeder on people. METHODS: Here, we assess the competence of O. detritus for three major arboviruses: dengue virus (DENV), chikungunya virus (CHIKV) and West Nile virus (WNV) using adult mosquitoes reared from wild, field-obtained immatures. RESULTS: We demonstrate laboratory competence for WNV at 21 °C, with viral RNA detected in the mosquito's saliva 17 days after oral inoculation. By contrast, there was no evidence of laboratory competence of O. detritus for either DENV or CHIKV. CONCLUSIONS: To our knowledge, this is the first study to demonstrate competence of a UK mosquito for WNV and confirms that O. detritus may present a potential risk for arbovirus transmission in the UK and that further investigation of its vector role in the wild is required.


Subject(s)
Aedes/virology , Chikungunya virus/physiology , Dengue Virus/physiology , Insect Vectors/virology , Ochlerotatus/virology , West Nile virus/physiology , Animals , Female , United Kingdom
7.
Int J Environ Res Public Health ; 11(2): 1261-78, 2014 Jan 23.
Article in English | MEDLINE | ID: mdl-24464236

ABSTRACT

BACKGROUND: The majority of modern war wounds are characterized by high-energy blast injuries containing a wide range of retained foreign materials of a metallic or composite nature. Health effects of retained fragments range from local or systemic toxicities to foreign body reactions or malignancies, and dependent on the chemical composition and corrosiveness of the fragments in vivo. Information obtained by chemical analysis of excised fragments can be used to guide clinical decisions regarding the need for fragment removal, to develop therapeutic interventions, and to better anticipate future medical problems from retained fragment related injuries. In response to this need, a new U.S Department of Defense (DoD) directive has been issued requiring characterization of all removed fragments to provide a database of fragment types occurring in combat injuries. OBJECTIVES: The objective of this study is to determine the chemical composition of retained embedded fragments removed from injured military personnel, and to relate results to histological findings in tissue adjacent to fragment material. METHODS: We describe an approach for the chemical analysis and characterization of retained fragments and adjacent tissues, and include case examples describing fragments containing depleted uranium (DU), tungsten (W), lead (Pb), and non-metal foreign bodies composed of natural and composite materials. Fragments obtained from four patients with penetrating blast wounds to the limbs were studied employing a wide range of chemical and microscopy techniques. Available adjacent tissues from three of the cases were histologically, microscopically, and chemically examined. The physical and compositional properties of the removed foreign material surfaces were examined with energy dispersive x-ray fluorescence spectrometry (EDXRF), scanning electron microscopy (SEM), laser ablation inductively-coupled plasma mass-spectrometry (LA-ICP-MS), and confocal laser Raman microspectroscopy (CLRM). Quantitative chemical analysis of both fragments and available tissues was conducted employing ICP-MS. RESULTS: Over 800 fragments have been characterized and included as part of the Joint Pathology Center Embedded Fragment Registry. Most fragments were obtained from penetrating wounds sustained to the extremities, particularly soft tissue injuries. The majority of the fragments were primarily composed of a single metal such as iron, copper, or aluminum with traces of antimony, titanium, uranium, and lead. One case demonstrated tungsten in both the fragment and the connected tissue, together with lead. Capsular tissue and fragments from a case from the 1991 Kuwait conflict showed evidence of uranium that was further characterized by uranium isotopic ratios analysis to contain depleted uranium. CONCLUSIONS: The present study provides a systematic approach for obtaining a full chemical characterization of retained embedded fragments. Given the vast number of combat casualties with retained fragments, it is expected that fragment analysis will have significant implications for the optimal short and long-term care of wounded service members.


Subject(s)
Foreign Bodies/pathology , Military Personnel , Registries , Uranium/analysis , Wounds, Penetrating/pathology , Adult , Humans , Lead/analysis , Male , Tungsten/analysis , Young Adult
8.
J Immunotoxicol ; 11(2): 148-59, 2014.
Article in English | MEDLINE | ID: mdl-23895378

ABSTRACT

Tungstate (WO²â»4) has been identified as a ground water contaminant at military firing ranges and can be absorbed by ingestion. In this study, C57BL6 mice were exposed to sodium tungstate (Na2WO4·2H2O) (0, 2, 62.5, 125, and 200 mg/kg/day) in their drinking water for an initial 28-day screen and in a one-generation (one-gen) model. Twenty-four hours prior to euthanasia, mice were intraperitoneally injected with Staphylococcal enterotoxin B (SEB) (20 µg/mouse) or saline as controls. After euthanasia, splenocytes and blood were collected and stained with lymphocyte and/or myeloid immunophenotyping panels and analyzed by flow cytometry. In the 28-day and one-gen exposure, statistically significant reductions were observed in the quantities of activated cytotoxic T-cells (TCTL; CD3(+)CD8(+)CD71(+)) and helper T-cells (TH; CD3(+)CD4(+)CD71(+)) from spleens of SEB-treated mice. In the 28-day exposures, CD71(+) TCTL cells were 12.87 ± 2.05% (SE) in the 0 tungstate (control) group compared to 4.44 ± 1.42% in the 200 mg/kg/day (p < 0.001) group. TH cells were 4.85 ± 1.23% in controls and 2.76 ± 0.51% in the 200 mg/kg/day (p < 0.003) group. In the one-gen exposures, TCTL cells were 7.98 ± 0.49% and 6.33 ± 0.49% for P and F1 mice after 0 mg/kg/day tungstate vs 1.58 ± 0.23% and 2.52 ± 0.25% after 200 mg/kg/day of tungstate (p < 0.001). Similarly, TH cells were reduced to 6.21 ± 0.39% and 7.20 ± 0.76%, respectively, for the 0 mg/kg/day P and F1 mice, and 2.28 ± 0.41% and 2.85 ± 0.53%, respectively, for the 200 mg/kg/day tungstate P and F1 groups (p < 0.001). In delayed-type hypersensitivity Type IV experiments, tungstate exposure prior to primary and secondary antigen challenge significantly reduced footpad swelling at 20 and 200 mg/kg/day. These data indicate that exposure to tungstate can result in immune suppression that may, in turn, reduce host defense against pathogens.


Subject(s)
Adaptive Immunity/drug effects , Tungsten Compounds/pharmacology , Administration, Oral , Animals , Enterotoxins , Female , Hypersensitivity, Delayed/immunology , Immunophenotyping , Interferon-gamma/biosynthesis , Male , Mice , Mice, Inbred C57BL , T-Lymphocytes, Cytotoxic/immunology
9.
J Trauma Acute Care Surg ; 75(2 Suppl 2): S115-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23883895

ABSTRACT

BACKGROUND: The implementation of a human research protection program in Afghanistan and the mobilization of the combat casualty research team have made it possible to design and efficiently conduct multifaceted, multisite, and prospective research studies in a combat environment. Still, to conduct research in such an environment, several unique challenges must be overcome. METHODS: This article describes the development and conduct of three ongoing trauma-related biomedical research studies in Afghanistan, highlighting the challenges and lessons learned within the context of these studies. RESULTS: Key challenges include the process of developing and getting approval for in-theater research protocols, the informed consent process, and logistics of conducting a biomedical research study in an austere environment. Despite these challenges, important lessons learned that can contribute to the success of a protocol include the need for clear operating procedures, judicious selection for which data points must be collected in-theater, and the importance anticipating the "fog and friction" of war. CONCLUSION: As we continue the journey toward more sophisticated research capabilities in combat, this article will help inform the design and conduct of future research performed in a theater of war. Conducting biomedical research in a combat zone is an important but difficult element of military medicine.


Subject(s)
Afghan Campaign 2001- , Biomedical Research/methods , Military Medicine/methods , Biomedical Research/organization & administration , Humans , Informed Consent , Military Medicine/organization & administration , United States , Wounds and Injuries/surgery , Wounds and Injuries/therapy
10.
Inhal Toxicol ; 24(2): 109-24, 2012.
Article in English | MEDLINE | ID: mdl-22283445

ABSTRACT

Respiratory symptoms are frequently reported in personnel deployed to the Middle East. This project characterized the respiratory toxicity of inhaled Iraqi sand (IS). Adult rats underwent a 6-wk inhalation to air or mainstream cigarette smoke (MSCS) (3 h/d, 5 d/wk) that included exposure to IS or crystalline silica (1 mg/m(3), 19 h/d, 7 d/wk) or air during the last 2 weeks. Assessments included motor activity, whole-body plethysmography, cytological and biochemical analysis of bronchoalveolar lavage fluid, lung metal burden, nasal and lung pathology, and changes in lung protein and gene expression. A number of metals including nickel, manganese, vanadium, and chromium were detected in IS. Elevated lung parenchyma aluminum, silica, barium, manganese, and vanadium concentrations were seen in IS-exposed rats, suggesting that several metals present in IS are bioavailable. Rats exposed to IS only developed mild inflammation in the anterior nose and lung. Silica inhalation was associated with some pulmonary responses that were not seen in IS-exposed rats, such as mild laryngeal and tracheal inflammation, mild tracheal epithelial hyperplasia, and elevated lung silica concentrations. MSCS inhalation with or without co-exposure to either IS or silica resulted in changes consistent with pulmonary inflammation and stress response. Rats exposed to MSCS and silica had more widespread airway lesions when compared with rats exposed to MSCS only. Silica-exposed rats had more robust pulmonary gene expression and proteomic responses than that seen in IS-exposed rat. Our studies show that the respiratory toxicity of IS is qualitatively similar to or less than that seen following short-term silica exposure.


Subject(s)
Air Pollutants/toxicity , Dust , Metals/toxicity , Silicon Dioxide/toxicity , Tobacco Smoke Pollution/adverse effects , Administration, Inhalation , Animals , Behavior, Animal/drug effects , Bronchial Provocation Tests , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Dust/analysis , Gene Expression/drug effects , Hand Strength , Iraq , Larynx/drug effects , Larynx/pathology , Lung/drug effects , Lung/pathology , Lung/physiology , Male , Metals/analysis , Motor Activity/drug effects , Oligonucleotide Array Sequence Analysis , Rats , Rats, Sprague-Dawley , Respiratory Function Tests , Respiratory Mucosa/drug effects , Respiratory Mucosa/pathology , Silicon Dioxide/analysis , Trachea/drug effects , Trachea/pathology
12.
Chem Res Toxicol ; 24(4): 488-93, 2011 Apr 18.
Article in English | MEDLINE | ID: mdl-21375269

ABSTRACT

Heavy metal tungsten alloys have replaced lead and depleted uranium in many munitions applications, due to public perception of these elements as environmentally unsafe. Tungsten materials left in the environment may become bioaccessible as tungstate, which might lead to population exposure through water and soil contamination. Although tungsten had been considered a relatively inert and toxicologically safe material, recent research findings have raised concerns about possible deleterious health effects after acute and chronic exposure to this metal. This investigation describes tissue distribution of tungsten in mice following oral exposure to sodium tungstate. Twenty-four 6-9 weeks-old C57BL/6 laboratory mice were exposed to different oral doses of sodium tungstate (0, 62.5, 125, and 200 mg/kg/d) for 28 days, and after one day, six organs were harvested for trace element analysis with inductively coupled plasma mass spectrometry (ICP-MS). Kidney, liver, colon, bone, brain, and spleen were analyzed by sector-field high-resolution ICP-MS. The results showed increasing tungsten levels in all organs with increased dose of exposure, with the highest concentration found in the bones and the lowest concentration found in brain tissue. Gender differences were noticed only in the spleen (higher concentration of tungsten in female animals), and increasing tungsten levels in this organ were correlated with increased iron levels, something that was not observed for any other organ or either of the two other metals analyzed (nickel and cobalt). These findings confirmed most of what has been published on tungsten tissue distribution; they also showed that the brain is relatively protected from oral exposure. Further studies are necessary to clarify the findings in splenic tissue, focusing on possible immunological effects of tungsten exposure.


Subject(s)
Tungsten Compounds/pharmacokinetics , Administration, Oral , Animals , Cobalt/analysis , Cobalt/metabolism , Cobalt/toxicity , Female , Iron/analysis , Iron/metabolism , Iron/toxicity , Male , Mass Spectrometry , Mice , Mice, Inbred C57BL , Nickel/analysis , Nickel/metabolism , Nickel/toxicity , Tissue Distribution , Tungsten Compounds/administration & dosage , Tungsten Compounds/toxicity
13.
Toxicol Mech Methods ; 21(6): 435-43, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21417633

ABSTRACT

Exposure to manganese (Mn) occurs in both civilian and military operations. Mn exposure results in a movement disorder termed manganism, which resembles Parkinson's disease (PD). However, the pathogenic mechanisms underlying this disorder are not fully understood. α-Synuclein, a presynaptic protein is implicated in some neurodegenerative disorders, including PD and Mn-induced apoptosis, and its overexpression contributes to the loss of dopaminergic neurons. Although the role of α-synuclein in this process is widely documented, its exact function is not clear. The objective of this study was to evaluate the mechanism(s) of dopaminergic degeneration associated with α-synuclein expression in response to Mn exposure and to assess the role of nuclear factor-κB (NF-κB) activation as an intermediary of Mn-induced neurotoxicity. Rat mesencephalic cells (MES 23.5) overexpressing human α-synuclein show enhanced susceptibility to Mn exposure as evidenced by increased apoptosis and NF-κB nuclear translocation. Pretreatment with antioxidants and the p38 mitogen-activated protein kinase (MAPK) inhibitor SB239063 significantly diminished NF-κB activation, supporting a role for oxidative stress and p38 MAPK in Mn-induced NF-κB activation. In addition, increased nitric oxide generation was evident during NF-κB activation, which was blocked by NF-κB (SN50) and MAPK inhibitors. Mn-induced cell death was attenuated by SN-50 and specific nitric oxide synthase (NOS) inhibitor (1400W); corroborating NOS activation is mediated through NF-κB in the mechanism of cell death. These data indicate that the transcription factor NF-κB, p38 MAPK, and apoptotic signaling cascades are activated by Mn in human α-synuclein-overexpressing cells. Thus, α-synuclein may facilitate Mn-induced neurotoxicity, and along with NF-κB, it may play a role in dopaminergic cell death.


Subject(s)
Heavy Metal Poisoning, Nervous System/metabolism , Manganese/toxicity , NF-kappa B/metabolism , Nerve Tissue Proteins/biosynthesis , Neurons/drug effects , Signal Transduction/drug effects , alpha-Synuclein/biosynthesis , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Cell Line , Cell Nucleus/drug effects , Environmental Pollutants/toxicity , Heavy Metal Poisoning, Nervous System/pathology , Heavy Metal Poisoning, Nervous System/prevention & control , Humans , Hybrid Cells , Mesencephalon/drug effects , Mesencephalon/metabolism , Mesencephalon/pathology , Mice , NF-kappa B/antagonists & inhibitors , Nerve Tissue Proteins/genetics , Neurons/metabolism , Neurons/pathology , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/metabolism , Oxidative Stress/drug effects , Protein Kinase Inhibitors/pharmacology , Protein Transport/drug effects , Rats , alpha-Synuclein/genetics , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors
14.
Inhal Toxicol ; 22(1): 69-76, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20017594

ABSTRACT

Aerosol cloud formation may occur when certain tungsten munitions strike hard targets, placing military personnel at increased risk of exposure. Although the pharmacokinetics of various forms of tungsten have been studied in animals following intravenous and oral administration, tungsten disposition following inhalation remains incompletely characterized. The objective of this study was to evaluate the pharmacokinetics of inhaled tungstate (WO(4)) in rats. Male, 16-wk-old, CD rats (n = 7 rats/time point) underwent a single, 90-min, nose-only exposure to an aerosol (mass median aerodynamic diameter [MMAD] 1.50 mum ) containing 256 mg W/m(3) as radiolabeled sodium tungstate (Na(2)(188)WO(4)). (188)W tissue concentrations were determined at 0, 1, 3, 7, and 21 days postexposure by gamma spectrometry. The thyroid and urine had the highest (188)W levels postexposure, and urinary excretion was the primary route of (188)W elimination. The pharmacokinetics of tungsten in most tissues was best described with a two-compartment pharmacokinetic model with initial phase half-lives of approximately 4 to 6 h and a longer terminal phase with half-lives of approximately 6 to 67 days. The kidney, adrenal, spleen, femur, lymph nodes, and brain continued to accumulate small amounts of tungsten as reflected by tissue:blood activity ratios that increased throughout the 21-day period. At day 21 all tissues except the thyroid, urine, lung, femur, and spleen had only trace levels of (188)W. Data from this study can be used for development and refinement of pharmacokinetic models for tungsten inhalation exposure in environmental and occupational settings.


Subject(s)
Tungsten Compounds/pharmacokinetics , Administration, Inhalation , Aerosols , Animals , Inhalation Exposure , Male , Metabolic Clearance Rate , Models, Biological , Radioisotopes , Rats , Rats, Sprague-Dawley , Tissue Distribution
15.
Toxicol Mech Methods ; 19(2): 123-8, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19778256

ABSTRACT

A whole body inhalation study of mixed jet fuel vapor and its aerosol necessitated the development of a method for preparing vapor only standards from the neat fuel. Jet fuel is a complex mixture of components which partitions between aerosol and vapor when aspirated based on relative volatility of the individual compounds. A method was desired which could separate the vapor portion from the aerosol component to prepare standards for the calibration of infrared spectrophotometers and a head space gas chromatography system. A re-circulating loop system was developed which provided vapor only standards whose composition matched those seen in an exposure system. Comparisons of nominal concentrations in the exposure system to those determined by infrared spectrophotometry were in 92-95% agreement. Comparison of jet fuel vapor concentrations determined by infrared spectrophotometry compared to head space gas chromatography yielded a 93% overall agreement in trial runs. These levels of agreement show the loop system to be a viable method for creating jet fuel vapor standards for calibrating instruments.


Subject(s)
Aircraft , Chromatography, Gas , Gases/chemistry , Hydrocarbons/analysis , Spectrophotometry, Infrared , Administration, Inhalation , Aerosols , Calibration , Chromatography, Gas/instrumentation , Chromatography, Gas/methods , Chromatography, Gas/standards , Humans , Spectrophotometry, Infrared/instrumentation , Spectrophotometry, Infrared/methods , Spectrophotometry, Infrared/standards , Volatilization
16.
Neurotoxicology ; 30(3): 414-22, 2009 May.
Article in English | MEDLINE | ID: mdl-19442826

ABSTRACT

The central nervous system (CNS) appears to be the critical target of manganese (Mn), and neurotoxicity has been the focus of most of the health effects of manganese. In brain, the mechanism underlying the Mn-induced cell death is not clear. We have previously demonstrated that NFkappabeta induction and the activation of nitric oxide synthase through reactive oxygen species (ROS) represent a proximate mechanism for Mn-induced neurotoxicity. In this study, an immortalized dopaminergic cells were used to characterize the cell death signaling cascade activated by manganese. Exposure to Mn resulted in a time and concentration-related loss of cell viability as observed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and live/dead cell assay. Mn increased BNIP3 expression within 3h and continued to increase up to 24h exposure followed by a concentration-related apoptotic death as determined by TUNEL. Further, Mn treatment resulted in accumulation of reactive oxygen species and mitochondrial dysfunction with loss of mitochondrial membrane potential and release of cytochrome c. Antioxidants significantly reduced Mn-induced BNIP3 expression and attenuated cell death, demonstrating the role of oxidative stress in BNIP3 induction. Blocking BNIP3 up-regulation with a transcription or a translational inhibitor reduced the response to manganese. Cell death by manganese was reduced in the presence of CsA (PT pore inhibitor). In addition, knockdown of BNIP3 by small interfering RNA (siRNA) improved mitochondrial recovery and reduced neuronal cell loss suggesting that constitutive expression of BNIP3 plays a role in Mn-induced neurotoxicity by regulating mitochondrial functions. These findings indicate a potential detrimental role of BNIP3 in manganese-induced neuronal cell death.


Subject(s)
Manganese/toxicity , Membrane Potential, Mitochondrial/drug effects , Membrane Proteins/metabolism , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/metabolism , Mitochondrial Proteins/metabolism , Neurons/drug effects , Trace Elements/toxicity , Animals , Apoptosis , Cell Line, Tumor , Cyclosporine/pharmacology , Cytochromes c/metabolism , Enzyme Inhibitors/pharmacology , Manganese/antagonists & inhibitors , Mice , Neurons/ultrastructure , Oxidative Stress/drug effects , Rats , Trace Elements/antagonists & inhibitors , Up-Regulation
17.
Neurotoxicology ; 30(3): 445-50, 2009 May.
Article in English | MEDLINE | ID: mdl-19442830

ABSTRACT

Olfactory transport of represents an important mechanism for direct delivery of certain metals to the central nervous system (CNS). The objective of this study was to determine whether inhaled tungsten (W) undergoes olfactory uptake and transport to the rat brain. Male, 16-week-old, Sprague-Dawley rats underwent a single, 90-min, nose-only exposure to a Na(2)(188)WO(4) aerosol (256 mg W/m(3)). Rats had the right nostril plugged to prevent nasal deposition of (188)W on the occluded side. The left and right sides of the nose and brain, including the olfactory pathway and striatum, were sampled at 0, 1, 3, 7, and 21 days post-exposure. Gamma spectrometry (n=7 rats/time point) was used to compare the levels of (188)W found on the left and right sides of the nose and brain and blood to determine the contribution of olfactory uptake to brain (188)W levels. Respiratory and olfactory epithelial samples from the side with the occluded nostril had significantly lower end-of-exposure (188)W levels confirming the occlusion procedure. Olfactory bulb, olfactory tract/tubercle, striatum, cerebellum, rest of brain (188)W levels paralleled blood (188)W concentrations at approximately 2-3% of measured blood levels. Brain (188)W concentrations were highest immediately following exposure, and returned to near background concentrations within 3 days. A statistically significant difference in olfactory bulb (188)W concentration was seen at 3 days post-exposure. At this time, (188)W concentrations in the olfactory bulb from the side ipsilateral to the unoccluded nostril were approximately 4-fold higher than those seen in the contralateral olfactory bulb. Our data suggest that the concentration of (188)W in the olfactory bulb remained low throughout the experiment, i.e., approximately 1-3% of the amount of tungsten seen in the olfactory epithelium suggesting that olfactory transport plays a minimal role in delivering tungsten to the rat brain.


Subject(s)
Corpus Striatum/metabolism , Olfactory Pathways/metabolism , Tungsten Compounds/administration & dosage , Tungsten Compounds/pharmacokinetics , Administration, Inhalation , Aerosols , Animals , Male , Pituitary Gland/metabolism , Rats , Rats, Sprague-Dawley , Tissue Distribution , Tungsten Compounds/blood
18.
Neurotoxicol Teratol ; 30(6): 455-61, 2008.
Article in English | MEDLINE | ID: mdl-18675901

ABSTRACT

The use of tungsten as a replacement for lead and depleted uranium in munitions began in the mid 1990's. Recent reports demonstrate tungsten solubilizes in soil and can migrate into drinking water supplies and therefore is a potential health risk to humans. This study evaluated the reproductive and neurobehavioral effects of sodium tungstate in Sprague-Dawley rats following 70 days of daily pre- and postnatal exposure. Adult male and female rats were orally dosed with diH(2)O vehicle, 5 or 125 mg/kg/day of sodium tungstate through mating, gestation, and weaning (PND 0-20). Daily administration of sodium tungstate produced no overt evidence of toxicity and had no apparent effect on mating success or offspring physical development. Distress vocalizations were elevated in the highest dose group. There was no treatment related effect on righting reflex latencies, however, the males had significantly shorter latencies than the females. Locomotor activity was affected in both the low and high dose groups of F0 females. Those in the low dose group showed increased distance traveled, more time in ambulatory movements, and less time in stereotypic behavior than controls or high dose animals. The high dose group had more time in stereotypical movements than controls, and less time resting than controls and the lowest exposure group. Maternal retrieval was not affected by sodium tungstate exposure and there were no apparent effects of treatment on F1 acoustic startle response or water maze navigation. Overall, the results of this study suggest pre- and postnatal oral exposure to sodium tungstate may produce subtle neurobehavioral effects in offspring related to motor activity and emotionality. These findings warrant further investigation to characterize the neurotoxicity of sodium tungstate on dams and their developing pups.


Subject(s)
Behavior, Animal/drug effects , Maternal Behavior/drug effects , Motor Activity/drug effects , Prenatal Exposure Delayed Effects , Tungsten Compounds/toxicity , Acoustic Stimulation/adverse effects , Analysis of Variance , Animals , Animals, Newborn , Emotions/drug effects , Female , Male , Maze Learning/drug effects , Pregnancy , Rats , Rats, Sprague-Dawley , Reflex/drug effects , Reflex, Startle/drug effects , Reproduction/drug effects
19.
Obstet Gynecol ; 110(4): 788-92, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17906010

ABSTRACT

OBJECTIVE: To assess whether the G allele of the serotonin receptor 1A C(-1019)G polymorphism is associated with premenstrual dysphoric disorder. METHODS: The study sample comprised 53 women with clinically diagnosed premenstrual dysphoric disorder (age range 27-46 years, mean 37.7 years) and 51 healthy control subjects (age range 22-48 years, mean 36.2 years). The serotonin receptor 1A C(-1019)G polymorphism was genotyped and compared between the two groups. RESULTS: In contrast to the postulated "high-risk" G/G genotype, there was a marked overrepresentation of the C/C genotype in the premenstrual dysphoric disorder group (P=.034; odds ratio 3.63, 95% confidence interval 1.22-10.78). The presence of at least one C allele was associated with a 2.5-fold increased risk of premenstrual dysphoric disorder (P=.053; odds ratio 2.46, 95% confidence interval 1.03-5.88). CONCLUSION: Our hypothesis that the high-risk G allele is associated with the occurrence of premenstrual dysphoria was not proved in this study. However, due to the increased prevalence of the C variant, we suggest that the C(-1019) allele may contribute to the risk of premenstrual dysphoria. LEVEL OF EVIDENCE: II.


Subject(s)
Mood Disorders/genetics , Premenstrual Syndrome/genetics , Receptor, Serotonin, 5-HT1A/genetics , Adolescent , Adult , Alleles , Case-Control Studies , Female , Humans , Middle Aged , Polymorphism, Single Nucleotide , Premenstrual Syndrome/psychology , Risk Factors
20.
Am J Trop Med Hyg ; 75(5): 1017-20, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17124005

ABSTRACT

Since the first HIV case was diagnosed in the Czech Republic in 1985, there is a lack of information regarding the epidemiology of HIV infection in most high-risk groups. To determine the prevalence of, and risk factors for, HIV among female and male commercial sex workers (FCSW and MCSW, respectively) and injecting drug users (IDUs), cross-sectional studies were conducted in the cities of Cheb, Usti nad Labem, Ostrava, and Prague of the Czech Republic. A total of 1,277 subjects were enrolled, which included 585 FCSWs, 230 MCSWs, and 462 IDUs. The HIV prevalences were 0.7% (95% CI: 0.2-1.7%), 0.9% (95% CI: 0.1-3.1%), and 0.2% (95% CI: 0.005-1.2%) among FCSWs, MCSWs, and IDUs, respectively. Although low HIV prevalences were found, ongoing sentinel surveillance studies, which address modifiable behavioral and biologic risk factors among high-risk groups, are necessary to guide strategies to stem the tide of the epidemic in this country.


Subject(s)
HIV Infections/epidemiology , HIV Seropositivity/epidemiology , Sex Work , Substance Abuse, Intravenous , Adolescent , Adult , Cross-Sectional Studies , Czech Republic/epidemiology , Female , HIV Infections/diagnosis , Humans , Male , Risk-Taking , Sexual Behavior , Sexual Partners , Substance Abuse, Intravenous/virology
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